BACKGROUND
[0001] The present invention relates to a liquid crystal composition comprising a mesogen
containing compound and a compound selected from a photochromic compound, a dichroic
compound and a photochromic-dichroic compound, formulations thereof, optical elements,
liquid crystal polymers comprising same and methods of making same.
[0002] The molecules of a liquid crystal ("LC") tend to align with one another in a preferred
direction, yielding a fluid material with anisotropic optical, electromagnetic, and
mechanical properties. The mesogen is the fundamental unit of a LC which induces the
structural order in the liquid crystals.
[0003] Liquid crystal polymers ("LCPs") are polymers capable of forming regions of highly
ordered structure while in a liquid phase. LCPs have a wide range of uses, ranging
from strong engineering plastics to delicate gels for LC displays. The structure of
LCPs may consist of densely packed fibrous polymer chains that provide self-reinforcement
almost to the melting point of the polymer.
[0004] Dichroism may occur in LCs due to either the optical anisotropy of the molecular
structure or the presence of impurities or the presence of dichroic dyes. As used
herein, the term "dichroism", means the ability to absorb one of two orthogonal plane
polarized components of at least transmitted radiation more strongly than the other.
[0005] Conventional, linearly polarizing elements, such as linearly polarizing lenses for
sunglasses and linearly polarizing filters, are typically formed from stretched polymer
sheets containing a dichroic material, such as a dichroic dye. Consequently, conventional
linearly polarizing elements are static elements having a single, linearly polarizing
state. Accordingly, when a conventional linearly polarizing element is exposed to
either randomly polarized radiation or reflected radiation of the appropriate wavelength,
some percentage of the radiation transmitted through the element will be linearly
polarized. As used herein the term "linearly polarize" means to confine the vibrations
of the electric vector of light waves to one direction or plane.
[0006] Further, conventional linearly polarizing elements are typically tinted. That is,
conventional linearly polarizing elements contain a coloring agent (i.e., the dichroic
material) and have an absorption spectrum that does not vary in response to actinic
radiation. As used herein "actinic radiation" means electromagnetic radiation, such
to ultraviolet and visible radiation that is capable of causing a response. The color
of the conventional linearly polarizing element will depend upon the coloring agent
used to form the element, and most commonly, is a neutral color (for example, brown
or gray). Thus, while conventional linearly polarizing elements are useful in reducing
reflected light glare, because of their tint, they are not well suited for use under
certain low-light conditions. Further, because conventional linearly polarizing elements
have only a single, tinted linearly polarizing state, they are limited in their ability
to store or display information.
[0007] As discussed above, conventional linearly polarizing elements are typically formed
using sheets of stretched polymer films containing a dichroic material. As used herein
the term "dichroic" means capable of absorbing one of two orthogonal plane polarized
components of at least transmitted radiation more strongly than the other. Thus, while
dichroic materials are capable of preferentially absorbing one of two orthogonal plane
polarized components of transmitted radiation, if the molecules of the dichroic material
are not suitably positioned or arranged, no net linear polarization of transmitted
radiation will be achieved. That is, due to the random positioning of the molecules
of the dichroic material, selective absorption by the individual molecules will cancel
each other such that no net or overall linear polarizing effect is achieved. Thus,
it is generally necessary to suitably position or arrange the molecules of the dichroic
material by alignment with another material in order to achieve a net linear polarization.
[0008] In contrast to the dichroic elements discussed above, conventional photochromic elements,
such as photochromic lenses that are formed using conventional thermally reversible
photochromic materials, are generally capable of converting from a first state, for
example, a "clear state," to a second state, for example, a "colored state," in response
to actinic radiation, and then reverting back to the first state in response to thermal
energy. As used herein, the term "photochromic" means having an absorption spectrum
for at least visible radiation that varies in response to at least actinic radiation.
Thus, conventional photochromic elements are generally well suited for use in both
low-light conditions and bright conditions. However, conventional photochromic elements
that do not include linearly polarizing filters are generally not adapted to linearly
polarize radiation. That is, the absorption ratio of conventional photochromic elements,
in either state, is generally less than two. As used herein, the term "absorption
ratio" refers to the ratio of absorbance of radiation linearly polarized in a first
plane to the absorbance of the same wavelength radiation linearly polarized in a plane
orthogonal to the first plane, wherein the first plane is taken as the plane with
the highest absorbance. Therefore, conventional photochromic elements cannot reduce
reflected light glare to the same extent as conventional linearly polarizing elements.
Thus, photochromic-dichroic materials have been developed. Photochromic-dichroic materials
are materials that display photochromic properties (i.e., having an absorption spectrum
for at least visible radiation that varies in response to at least actinic radiation)
and dichroic properties (i.e., capable of absorbing one of two orthogonal plane polarized
components of at least transmitted radiation more strongly than the other).
[0009] Photochromic materials and photochromic-dichroic materials may be incorporated into
a substrate or an organic material, for example a polymer substrate, including LCP
substrates. When photochromic materials and photochromic-dichroic materials undergo
a change from one state to another, the molecule(s) of the photochromic compound or
photochromic-dichroic compound may undergo a conformational change from one conformational
state to a second conformational state. This conformational change may result in a
change in the amount of space that the compound occupies. However, for certain photochromic
materials and certain photochromic-dichroic materials to effectively transition from
one state to another, for example to transition from a clear state to a colored state,
to transition from a colored state to a clear state, to transition from a non-polarized
state to a polarized state, and/or to transition from a polarized state to a non-polarized
state, the photochromic compound or photochromic-dichroic compound must be in an chemical
environment that is sufficiently flexible to allow the compound to transition from
one conformational state to the second conformational state at a rate that is sufficient
to provide the desired response on over an acceptable time frame. Therefore, new polymeric
materials, such as new LCPs, and materials to form these new materials are necessary
to further develop photochromic and photochromic-dichroic materials and substrates.
[0010] US 2008/0081133 discloses a liquid crystal composition in combination with a dichroic compound.
[0011] US 6,733,689 relates to a liquid-crystalline composition for printing inks and coatings that might
comprise a photochromic compound.
BRIEF SUMMARY OF THE DISCLOSURE
[0012] The present disclosure provides for a liquid crystal composition comprising:
- a mesogen containing compound represented by one of the following structures:

wherein each X is independently

b) each P is a reactive group independently selected from a group Q, amino, alkylamino,
nitro, acrylate, methacrylate, 2-chloroacrylate, 2-phenylacrylate, acryloylphenylene,
acrylamide, methacrylamide, 2-chloroacrylamide, 2-phenylacrylamide, oxetane, glycidyl,
cyano, vinyl ether, vinyl ester, a styrene derivative, siloxane, ethyleneimine derivatives,
or substituted or unsubstituted chiral or non-chiral monovalent or divalent groups
chosen from steroid radicals, terpenoid radicals, alkaloid radicals and mixtures thereof,
wherein the substituents are independently chosen from alkyl, alkoxy, amino, cycloalkyl,
alkylalkoxy, fluoroalkyl, cyano, cyanoalkyl, cyanoalkoxy or mixtures thereof, or P
is a structure having from 2 to 4 reactive groups or P is an unsubstituted or substituted
ring opening metathesis polymerization precursor;
c) the group Q is hydroxy, amine, alkenyl, alkynyl, azido, silyl, silylhydride, oxy(tetrahydro-2H-pyran-2-yl),
thiol, isocyanato, thioisocyanato, acryloxy, methacryloxy, 2-(acryloxy)ethylcarbamyl,
2-(methacryloxy)ethylcarbamyl, aziridinyl, allyloxycarbonyloxy, epoxy, carboxylic
acid, carboxylic acid derivatives particularly selected from carboxylic ester, amide
and carboxylic anhydride, or acyl halide, preferably the carboxylic acid derivatives
are selected from itaconic acid ester, maleic acid derivatives, fumaric acid derivatives,
unsubstituted cinnamic acid derivatives, cinnamic acid derivatives that are substituted
with at least one of methyl, methoxy, cyano and halogen;
d) each L is independently chosen for each occurrence, the same or different, from
a single bond, a polysubstituted, monosubstituted, unsubstituted or branched spacer
independently chosen from arylene, (C1-C30)alkylene, (C1-C30)alkylenecarbonyloxy, (C1-C30)alkyleneamino, (C1-C30)alkyleneoxy, (C1-C30)perfluoroalkylene, (C1-C30)perfluoroalkyleneoxy, (C1-C30)alkylenesilyl, (C1-C30)dialkylenesiloxyl, (C1-C30)alkylenecarbonyl, (C1-C30)alkyleneoxycarbonyl, (C1-C30)alkylenecarbonylamino, (C1-C30)alkyleneaminocarbonyl, (C1-C30)alkyleneaminocarbonyloxy, (C1-C30)alkyleneaminocarbonylamino, (C1-C30)alkyleneurea, (C1-C30)alkylenethiocarbonylamino, (C1-C30)alkyleneaminocarbonylthio, (C2-C30)alkenylene, (C1-C30)thioalkylene, (C1-C30)alkylenesulfone, or (C1-C30)alkylenesulfoxide, wherein each substituent is independently chosen from (C1-C5)alkyl, (C1-C5)alkoxy, fluoro, chloro, bromo, cyano, (C1-C5)alkanoate ester, isocyanato, thioisocyanato, or phenyl;
e) the group R is selected from hydrogen, C1-C18 alkyl, C1-C18 alkoxy, C1-C18 alkoxycarbonyl, C3-C10 cycloalkyl, C3-C10 cycloalkoxy, poly(C1-C18 alkoxy), or a straight-chain or branched C1-C18 alkyl group that is unsubstituted or substituted with cyano, fluoro, chloro, bromo,
or C1-C18 alkoxy, or poly-substituted with fluoro, chloro, or bromo; and
f) the groups Mesogen-1 and Mesogen-2 are each independently a rigid straight rod-like
liquid crystal group, a rigid bent rod-like liquid crystal group, or a rigid disc-like
liquid crystal group;
g) the group T is selected from P and hydrogen, aryl, alkyl, alkoxy, alkylalkoxy,
alkoxyalkoxy, polyalkylether, (C1-C6)alkyl(C1-C6)-alkoxy(C1-C6)alkyl, polyethyleneoxy
and polypropyleneoxy.
wherein
w is 1, y is an integer from 2 to 25, and z is 1;
and
in -(L)y- and -(L)w- no two arylene groups are linked by a single bond;
or residue thereof;
- a compound selected from a photochromic compound, a dichroic compound and a photochromic-dichroic
compound; and
- optionally a liquid crystal polymer.
[0013] According to another embodiment, the present disclosure provides for an optical element
comprising a substrate and an at least partial layer on at least a portion of the
substrate, the layer comprising a liquid crystal composition as described herein.
[0014] Still another embodiment of the present disclosure provides for an ophthalmic element
comprising a substrate and an at least partial layer comprising a liquid crystal composition
as described herein on at least a portion of a surface of the substrate. Preferably,
the dichroic compound and the photochromic-dichroic compound are at least partially
aligned. The composition may further comprise one or more additives; a liquid crystal
polymer, preferably having a Fischer microhardness ranging from 0 Newtons/mm
2 to 150 Newtons/mm
2. According to these embodiments, the one or more additives are selected from the
group consisting of a liquid crystal, a liquid crystal property control additive,
a non-linear optical material, a dye, an alignment promoter, a kinetic enhancer, a
photoinitiator, a thermal initiator, a surfactant, a polymerization inhibitor, a solvent,
a light stabilizer, a thermal stabilizer, a mold release agent, a rheology control
agent, a gelator, a leveling agent, a free radical scavenger, a coupling agent, a
tilt control additive, a block or non-block polymeric material, and an adhesion promoter.
[0015] Further embodiments of the present disclosure provide for a liquid crystal cell comprising
a first substrate having a first surface, a second substrate having a second surface,
wherein the second surface of the second substrate is opposite and spaced apart from
the first surface of the first substrate so as to define a region, and a liquid crystal
composition as described herein positioned within the region defined by the first
surface and the second surface.
[0016] Still further embodiments of the present disclosure provide for an article of manufacture
comprising a composition comprising a liquid crystal composition as described herein.
[0017] Other embodiments of the present disclosure provide for a method of forming an ophthalmic
element. The method comprises formulating a liquid crystal composition as described
herein; coating at least a portion of a substrate with the liquid crystal composition;
at least partially aligning at least a portion of the liquid crystal composition in
the coating; and curing the liquid crystal coating layer.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0018] Aspects of the present disclosure will be better understood when read in conjunction
with the figures, in which:
[0019] Figures 1-3 illustrate exemplary methods for synthesizing certain embodiments of
the mesogen containing compounds described herein. In particular:
Figures 1 and 2 illustrate two processes for synthesizing bi-mesogen containing compounds
having structures according to Formula IV;
Figure 3 illustrates the use of a Mitsunobo coupling reaction for synthesizing a bi-mesogen
containing compound having a structure according to Formula IV.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0020] As used in this specification and the appended claims, the articles "a", "an", and
"the" include plural references unless expressly and unequivocally limited to one
referent.
[0021] Liquid crystal compositions and formulations containing the mesogen containing compounds
according to various embodiments of the present disclosure will now be described.
According to certain embodiments, the formulations and compositions may be used, for
example liquid crystal polymers ("LCPs"), in optical elements such as, for example,
ophthalmic elements, display elements, windows, and mirrors. According to certain
embodiments, the mesogen containing compounds of the present disclosure may act as
monomers for the formation of LCPs.
[0022] The mesogen is the fundamental unit of a liquid crystal ("LC"), which induces the
structural order in the liquid crystal. The mesogenic portion of the LC typically
comprises a rigid moiety which aligns with other mesogenic components in the LC composition,
thereby aligning the LC molecules in one direction. The rigid portion of the mesogen
may consist of a rigid molecular structure, such as a mono or polycyclic ring structure,
including, for example a mono or polycyclic aromatic ring structures. Examples of
potential mesogens are set forth in greater detail herein and include those mesogenic
compounds set forth in
Demus et al., "Flüssige Kristalle in Tabellen," VEB Deutscher Verlag für Grundstoffindustrie,
Leipzig, 1974 and "
Flüssige Kristalle in Tabellen II," VEB Deutscher Verlag für Grundstoffindustrie,
Leipzig, 1984. LCs may also include one or more flexible portions in the LC molecule. The one or
more flexible portions may impart fluidity to the LC. LCs may exist in a non-ordered
state or an ordered (or aligned) state. The LC molecules in the non-ordered state
will adopt an essentially random orientation, that is there will be no general orientation
to the LC molecules. The LC molecules in the ordered or aligned state will generally
adopt an orientation where the mesogenic portions of the LC molecules are at least
partially aligned throughout the LC material. As used herein, the terms "align" or
"aligned" means to bring into suitable arrangement or position by interaction with
another material, compound or structure. In certain embodiments, the mesogenic portions
of the LC molecules may be at least partially aligned in a parallel orientation. In
other embodiments, the mesogenic portions of the LC molecules may be at least partially
aligned in a helical orientation, such as in a reflective polarizer.
[0023] The mesogen containing compounds of the present disclosure may be used for a variety
of functions, such as, , as LC compositions and as monomers for the synthesis of LCPs.
The mesogen containing compounds of the present disclosure may behave as monomers
to form polymers or may act as non-monomeric components, such as non-monomeric LC
components. In certain embodiments, the mesogen containing compounds may form crosslinked
networks or LCPs. As used herein the term "compound" means a substance formed by the
union of two or more elements, components, ingredients, or parts and includes, molecules
and macromolecules (for example polymers and oligomers) formed by the union of two
or more elements, components, ingredients, or parts. The compositions formed from
the mesogen containing compounds may have a variety of uses, including, as layers,
such as, cured coatings and films on at least a portion of a substrate, which may
impart certain desired characteristics to the substrate, and as articles of manufacture,
such as, molded articles, assembled articles and cast articles. For example, the compositions
formed from the mesogen containing compounds may be used, for example as at least
partial layers, coatings or films on at least a portion of a substrate which may impart
certain desired characteristics to the substrate, such as, for use in optical data
storage applications, as photomasks, as decorative pigments; in cosmetics and for
security applications (see, for example
U.S. Patent No. 6,217,948); as curable resins for medical, dental, adhesive and stereolithographic applications
(see, for example,
U.S. Patent No. 7,238,831); as articles of manufacture, such as, molded assembled, or cast articles for use
in the aforementioned applications and various related devices.
[0024] In certain embodiments, the mesogen containing compositions may be formulated into
LCs and/or LCPs which may be used or incorporated into optical elements such as, for
example, ophthalmic elements, display elements, windows, mirrors, active and passive
liquid crystal cells, elements and devices, and other LC or LCP containing articles
of interest, such as, polarizers, optical compensators (see, for example,
U.S. Patent No. 7,169,448), optical retarders (see, for example,
U.S. Reissue Patent No. RE39,605 E), color filters, and waveplates for lightwave circuits (see, for example,
U.S. Patent No. 7,058,249). For example, the LCPs may be used to form optical films such as retarders, wave
guides, reflectors, circular polarizers, wide view angle films, etc. As will be described
in more detail herein, the mesogen containing materials of various embodiments of
the present disclosure may be particularly suited to give the desired kinetic properties
for photochromic or photochromic-dichroic materials, such as in ophthalmic elements
and optical elements. In other embodiments, the LCPs may also be used as a host material
for organic photochromic materials such as thermally and non-thermally reversible
materials as well as photochromic/dichroic material, inorganic photochromic materials,
fluorescent or phosphorescent materials and non-linear optical materials ("NLOs").
Non-photosensitive materials may include fixed tint dyes, dichroic materials, thermochroic
materials, and pigments.
[0025] The mesogen containing compounds of the various embodiments of the present disclosure
generally comprise at least one mesogen unit, at least one reactive group, and at
least one flexible linking group as defined above which may be from 1 to 500 atomic
bonds in linear length and may therefore act as LCs, which may be incorporated into
materials or compositions which display LC properties or may be used as LC monomers,
for example, for the formation of LCPs.
[0026] According to various embodiments, the mesogen containing compounds of the present
disclosure may be represented by a compound having Formula I:

In Formula I, each X may be independently represented by a group represented by the
structure:

Further, in Formula I, each group P represents a reactive group as defined above.
For example, in certain embodiments, the reactive group may react with a group, react
with a comonomer or a reactive group on a developing polymer such that the structure
corresponding to Formula I or a residue thereof is incorporated into the polymer.
[0027] Further, in certain embodiments of P as defined above may be a reactive group comprising
a polymerizable group, wherein the polymerizable group may be any functional group
adapted to participate in a polymerization reaction. Examples of polymerization reactions
include those described in the definition of "polymerization" in
Hawley's Condensed Chemical Dictionary Thirteenth Edition, 1997, John Wiley & Sons,
pages 901-902. For example polymerization reactions include: "addition polymerization," in which
free radicals are the initiating agents that react with the double bond of a monomer
by adding to it on one side at the same time producing a new free electron on the
other side; "condensation polymerization," in which two reacting molecules combine
to form a larger molecule with elimination of a small molecule, such as a water molecule;
and "oxidative coupling polymerization." In an additional embodiment, P may be an
unsubstituted or substituted ring opening metathesis polymerization precursor. Further,
examples of polymerizable groups include hydroxy, acryloxy, methacryloxy, 2-(acryloxy)ethylcarbamyl,
2-(methacryloxy)ethylcarbamyl, isocyanato, aziridine, allylcarbonate, and epoxy, e.g.,
oxiranylmethyl. In other embodiments, P may have a structure having a plurality of
reactive groups, such as the reactive groups disclosed herein. For example, in certain
embodiments, P may have a structure having from 2 to 4 reactive groups, as described
herein. In certain embodiment, having multiple reactive groups on P may allow for
more effective incorporation into a polymer or allow for cross-linking between individual
polymer strands. Suitable examples of P groups with multiple reactive groups include
diacryloyloxy(C
1-C
6)alkyl; diacryloyloxyaryl; triacryloyloxy(C
1-C
6)alkyl; triacryloyloxyaryl; tetraacryloyloxy(C
1-C
6)alkyl; tetraacryloyloxyaryl; dihydroxy(C
1-C
6)alkyl; trihydroxy(C
1-C
6)alkyl; tetrahydroxy(C
1-C
6)alkyl; diepoxy(C
1-C
6)alkyl; diepoxyaryl; triepoxy(C
1-C
6)alkyl; triepoxyaryl; tetraepoxy(C
1-C
6)alkyl; tetraepoxyaryl; diglycidyloxy(C
1-C
6)alkyl; diglycidyloxyaryl; triglycidyloxy(C
1-C
6)alkyl; triglycidyloxyaryl; tetraglycidyloxy(C
1-C
6)alkyl; and tetraglycidyloxyaryl.
[0028] Further, with reference to Formula I, each group Q may represent hydroxy, amine,
alkenyl, alkynyl, azido, silyl, silylhydride, oxy(tetrahydro-2H-pyran-2-yl), isocyanato,
thiol, thioisocyanato, carboxylic acid, carboxylic ester, amide, carboxylic anhydride,
or acyl halide. In certain embodiments, the group Q may act as a reactive group such
that a mesogen containing compound comprising at least one group Q may be incorporated
into the backbone of a polymer or copolymer. For example, Q may be a polymerizable
group, such as those described herein, including a group selected from hydroxy, acryloxy,
methacryloxy, 2-(acryloxy)ethylcarbamyl, 2-(methacryloxy)ethylcarbamyl, isocyanato,
thiol, thioisocyanato, aziridine, allylcarbonate, carboxylic acid or carboxylic acid
derivative, and epoxy, e.g., oxiranylmethyl. As used herein, the terms "(meth)acryloxy"
and "(meth)acryloyloxy" are used interchangeably and refer to a substituted or unsubstituted
prop-2-en-1-oyloxy structure.
[0029] As described herein and with reference to Formula I, the groups L, (L)
y or (L)
w represents a linking group as defined above having preferably a linear length of
from 1 to 500 atomic bonds. That is, for the general structure F-L-E, the longest
linear length of the linking group between groups F and E (where groups F and E may
each generally represent any of groups P, R, Q, X T or a mesogen) may range from 1
to 500 bonds (inclusive of the intervening atoms). It should be understood that when
discussing the linear length of the linking group, one of ordinary skill in the art
will understand that the length of the linking group may be calculated by determining
the length of each of the bonds in the linear sequence and the distance occupied by
the various intervening atoms in the linear sequence of the linking group and totaling
the values. In certain embodiments, the longest linear sequence of bonds may be at
least 25 bonds between the linked groups. In other embodiments, the longest linear
sequence of bonds may be at least 30 bonds. In still other embodiments, the longest
linear sequence of bonds may be at least 50 bonds. It has been determined that, in
certain embodiments, a linking group L with at least 25 bonds improves a variety of
benefits for the resulting mesogen containing compound. For example, a linking group
of at least 25 bonds may improve the solubilities of the additives, such as the photochromic
compounds in compositions comprising the mesogen containing compounds; may provide
for faster or improved alignment properties of the compositions comprising the mesogen
containing compounds; and/or may lower the viscosity of a composition comprising the
mesogen containing compound.
[0030] Each group L may be independently chosen for each occurrence, the same or different,
from a single bond and the groups defined above. According to the various, "w" may
be represented by an integer from 1 to 26, "y" may be represented by an integer from
2 to 25, and "z" is either 1 or 2. It should be noted that when more than one L group
occurs in sequence, for example in the structure (L)
y or (L)
w where "y" and/or "w" is an integer greater than 1, then the adjacent L groups may
or may not have the same structure. That is, for example, in a linking group having
the structure -(L)
3- or -L-L-L- (i.e., where "y" or "w" is 3), each group -L- may be independently chosen
from any of the groups L recited above and the adjacent -L- groups may or may not
have the same structure. For example, in one exemplary embodiment, -L-L-L- may represent
-(C
1-C
30)alkyenel-(C
1-C
30)alkylene-(C
1-C
30)alkylene- (i.e., where each occurrence of -L- is represented by (C
1-C
30)alkylene, where each adjacent (C
1-C
30)alkylene group may have the same or different number of carbons in the alkylene group).
In another exemplary embodiment, -L-L-L- may represent -arylene-(C
1-C
30)alkylenesilyl-(C
1-C
30)alkyleneoxy- (i.e., where each occurrence of -L- differs from the adjacent groups
-L-). Thus, the structure of (L)
y or (L)
w should be understood as covering all possible combinations of the various sequences
of the linking groups -L-, including those where some or all of the adjacent -L- groups
are the same and where all the adjacent -L- groups are different, provided that no
two arylene groups are linked by a single bond.
[0031] Still with reference to Formula I, the group R represents an end group as defined
above.
[0032] With further reference to Formula I, in certain embodiments the groups Mesogen-1
and Mesogen-2 are each independently a rigid straight rod-like liquid crystal group,
a rigid bent rod-like liquid crystal, or a rigid disc-like liquid crystal group. The
structures for Mesogen-1 and Mesogen-2 may be any suitable mesogenic group known in
the art, for example, any of those recited in
Demus et al., "Flüssige Kristalle in Tabellen," VEB Deutscher Verlag für Grundstoffindustrie,
Leipzig, 1974 or "
Flüssige Kristalle in Tabellen II," VEB Deutscher Verlag für Grundstoffindustrie,
Leipzig, 1984. Further, according to certain embodiments, the groups Mesogen-1 and Mesogen-2 may
independently have a structure represented by:
-[S
1]
c-[G
1-[S
2]
d]
d'-[G
2-[S
3]
e]
e'-[G
3-[S
4]
f]
f'-S
5-
In certain embodiments, the mesogen structure, above, is further defined such that
each group each G
1, G
2, and G
3 may independently be chosen for each occurrence from: a divalent group chosen from:
an unsubstituted or a substituted aromatic group, an unsubstituted or a substituted
alicyclic group, an unsubstituted or a substituted heterocyclic group, and mixtures
thereof, wherein substituents are chosen from: thiol, amide, hydroxy(C
1-C
18)alkyl, isocyanato(C
1-C
18)alkyl, acryloyloxy, acryloyloxy(C
1-C
18)alkyl, halogen, C
1-C
18 alkoxy, poly(C
1-C
18 alkoxy), amino, amino(C
1-C
18)alkylene, C
1-C
18 alkylamino, di-(C
1-C
18)alkylamino, C
1-C
18 alkyl, C
2-C
18 alkene, C
2-C
18 alkyne, C
1-C
18 alkyl(C
1-C
18)alkoxy, C
1-C
18 alkoxycarbonyl, C
1-C
18 alkylcarbonyl, C
1-C
18 alkyl carbonate, aryl carbonate, perfluoro(C
1-C
18)alkylamino, di-(perfluoro(C
1-C
18)alkyl)amino, C
1-C
18 acetyl, C
3-C
10 cycloalkyl, C
3-C
10 cycloalkoxy, isocyanato, amido, cyano, nitro, a straight-chain or branched C
1-C
18 alkyl group that is mono-substituted with cyano, halo, or C
1-C
18 alkoxy, or poly-substituted with halo, and a group comprising one of the following
formulae: -M(T)
(t-1) and -M(OT)
(t-1), wherein M is chosen from aluminum, antimony, tantalum, titanium, zirconium and silicon,
T is chosen from organofunctional radicals, organofunctional hydrocarbon radicals,
aliphatic hydrocarbon radicals and aromatic hydrocarbon radicals, and t is the valence
of M. Further, in the mesogenic structure, "c", "d", "e", and "f" may be each independently
chosen from an integer ranging from 0 to 20, inclusive and "d"', "e"' and "f'" are
each independently an integer from 0 to 4 provided that a sum of d' + e' + f' is at
least 1. Still with reference to the mesogenic structure above, the groups S represent
spacer groups such that each of groups S
1, S
2, S
3, S
4, and S
5 may be independently chosen for each occurrence from a spacer unit chosen from:
- (A) -(CH2)g-, -(CF2)h-, -Si(CH2)g-, or -(Si(CH3)2O)n-, wherein "g" is independently chosen for each occurrence from 1 to 20 and "h" is
a whole number from 1 to 16 inclusive;
- (B) -N(Z)-, -C(Z)=C(Z)-, -C(Z)=N-, -C(Z')2-C(Z')2-, or a single bond, wherein Z is independently chosen for each occurrence from hydrogen,
C1-C6 alkyl, cycloalkyl and aryl, and Z' is independently chosen for each occurrence from
C1-C6 alkyl, cycloalkyl and aryl; or
- (C) -O-, -C(O)-, -C≡C-, -N=N-, -S-, -S(O)-, -S(O)(O)-, -(O)S(O)O-, -O(O)S(O)O- or
straight-chain or branched C1-C24 alkylene residue, said C1-C24 alkylene residue being unsubstituted, mono-substituted by cyano or halo, or poly-substituted
by halo;
provided that when two spacer units comprising heteroatoms are linked together the
spacer units are linked so that heteroatoms are not directly linked to each other
and when S
1 and S
5 are linked to another group, they are linked so that two heteroatoms are not directly
linked to each other.
[0033] According to various embodiments disclosed herein, in the structure of the mesogen,
above, "c", "d", "e", and "f" each can be independently chosen from an integer ranging
from 1 to 20, inclusive; and "d"', "e"' and "f'" each can be independently chosen
from 0, 1, 2, 3, and 4, provided that the sum of d' + e' + f' is at least 1. According
to other embodiments disclosed herein, "c", "d", "e", and "f" each can be independently
chosen from an integer ranging from 0 to 20, inclusive; and "d"', "e'" and "f'" each
can be independently chosen from 0, 1, 2, 3, and 4, provided that the sum of d' +
e' + f' is at least 2. According to still other embodiments disclosed herein, "c",
"d", "e", and "f" each can be independently chosen from an integer ranging from 0
to 20, inclusive; and "d"', "e"' and "f'" each can be independently chosen from 0,
1, 2, 3, and 4, provided that the sum of d' + e' + f' is at least 3. According to
still other embodiments disclosed herein, "c", "d", "e", and "f" each can be independently
chosen from an integer ranging from 0 to 20, inclusive; and "d'", "e"' and "f'" each
can be independently chosen from 0, 1, 2, 3, and 4, provided that the sum of d' +
e' + f' is at least 1.
[0034] Finally, with reference to Formula I, the structure of the mesogen containing compound
in the various embodiments of the present disclosure require that the group X is represented
by the structure

and "w" is 1, "y" is an integer from 2 to 25, and "z" is 1.
According to the present invention, the functional bi-mesogen containing compound
may have a structure represented by Formula I, wherein the group X is represented
by

"w" is 1, "y" is an integer from 2 to 25, and "z" is 1.
[0035] According to various embodiments, the mesogen containing compound of the present
disclosure, as represented by Formula I, may be a liquid crystal monomer. As used
herein, the term "liquid crystal monomer" means a monomeric compound that may display
liquid crystal properties in the monomeric state and/or in the polymeric state. That
is, the liquid crystal monomer may display liquid crystal properties by itself and/or
after it has been incorporated into a polymer or copolymer to form a LCP. One skilled
in the art will recognize that when the mesogen compound is in the polymeric state,
it has been reacted with other monomers and/or co-monomers to form the polymer and
is therefore a residue of the liquid crystal monomer.
[0036] Thus, embodiments of the present disclosure also contemplate a polymer or copolymer
which comprises the mesogen containing compounds or residues thereof according to
the various embodiments described herein. For example, according to one embodiment,
the polymer or copolymer may comprise the mesogen containing compound, such as a monomeric
compound which is suspended or mixed in the polymer or copolymer composition. In another
embodiment, the polymer or copolymer may comprise a residue of the mesogen containing
compound. According to one example, the residue of the mesogen containing compound
may be incorporated into the polymeric structure, for example, as part of the polymeric
backbone, or as a monomer incorporated into the backbone and forming a side chain
off the backbone. In another example, the residue of the mesogen containing compound
may have been reacted with another reactant (thereby forming the residue) and the
product of that reaction may be suspended or mixed into the polymer or copolymer.
[0037] According to certain embodiments, the polymer compositions comprising the mesogen
containing compounds or residues thereof, as described herein, may be liquid crystal
polymers. For example, the LCPs may be an anisotropic LCP, an isotropic LCP, a thermotropic
LCP or a lyotropic LCP. In various embodiments, the LCPs may display at least one
of a nematic phase, a smectic phase, a chiral nematic phase (i.e., a cholesteric phase),
a discotic phase (including chiral discotic), a discontinuous cubic phase, a hexagonal
phase, a bicontinuous cubic phase, a lamellar phase, a reverse hexagonal columnar
phase, or an inverse cubic phase. In addition, in certain LCPs of the present disclosure,
the LC monomers or residues thereof may transition from one phase to another, for
example, in response to thermal energy or actinic radiation.
[0038] The present disclosure provides for a bi-mesogen liquid crystal monomer represented
by the structure according to Formula IV.

According to these embodiments, each group P in Formula IV may independently be a
reactive group such as those set forth in the listing for P described herein and including
those P groups comprising polymerizable groups, a plurality of reactive groups, or
ring opening metathesis polymerization precursors. The group Q may independently be
any of those groups listed for group Q herein. Further, in either Formula IV or V,
the group (L) may be independently chosen for each occurrence, which may be the same
or different, from the listing of possible (L) groups set forth herein. In either
Formula IV or V, each group R may be independently selected from the listing of possible
R groups set forth herein. The mesogen components in either Formula IV or V may have
rigid straight rod-like liquid crystal groups, rigid bent rod-like liquid crystal
groups, rigid disc-like liquid crystal groups or a combination thereof. Thus, Mesogen-1
and Mesogen-2 of either Formula IV or V may be independently selected from the mesogen
structures set forth herein including those having the structure:
-[S
1]
c-[G
1-[S
2]
d]
d'-[G
2-[S
3]
e]
e'-[G
3-[S
4]
f]
f'-S
5-
as further defined herein. In addition, in Formulae IV and V, "w" may be an integer
ranging from 2 to 25.
[0039] According to the various embodiments of the mesogen containing compounds disclosed
herein, the structure of the mesogen containing compound, as represented by Formulae
IV as described in detail herein, may be designed to include a long flexible linking
group between one or more portions of the compound. For example, in the various structures
of the mesogen containing compounds disclosed herein, the linking groups -(L)y- and/or
-(L)
w- and in certain cases the group -(L)- (for example, when -(L)- comprises at least
25 linear bonds) may be a long flexible linking group comprising a long linear sequence
of chemical bonds, ranging from 25 to 500 chemical bonds in length, between the two
groups linked by the linking group. In certain embodiments the linking groups may
comprise a long linear sequence of chemical bonds ranging from 30 to 500 chemical
bonds in length between the two groups. In other embodiments the linking groups may
comprise a long linear sequence of chemical bonds ranging from 50 to 500 chemical
bonds in length between the two groups. As used with reference to the linking group,
the chemical bonds in the linear sequence between the groups linked by the linking
group may be covalent or polar covalent chemical bonds, such as covalent or polar
covalent σ-bonds and may also include one or more π-bonds (although the π-bonds are
not included when calculating the length of chemical bonds in the linear sequence).
Further, it will be understood by those skilled in the art that the linking group
also comprises those intervening atoms through which the linear sequence of bonds
are associated.
[0040] As will be described in greater detail herein, it is believed that the one or more
flexible linking group in the mesogen containing compounds disclosed herein impart
certain desirable characteristics to the compound and compositions, such as cured
compositions, formed therefrom. For example, while not wishing to be limited by any
interpretation, it is believed that the one or more flexible linking group in the
mesogen containing compound or residue thereof may result in cured compositions made
therefrom having a "softer" structure. As used herein, with reference to the character
of cured compositions, such as LCPs, layers, coatings, and coated articles made from
the compounds, the term "softer" refers to compositions exhibiting a Fischer microhardness
typically less than 150 Newtons/mm
2, e.g, from 0 to 149.9 Newtons/mm
2. Cured compositions having a softer structure may display desired or improved characteristics,
for example, improved LC character, improved photochromic performance, and improved
dichroic performance. For example, for cured compositions such as a polymer, a copolymer
or blends of (co)polymers, it may be desirable to have hard and soft segments or components
in the polymer. The concept that cured polymers may be composed of hard and soft segments
or components is known in the art (see, for example, "
Structure-Property-Relationship in Polyurethanes", Polyurethane Handbook, G. Oertel,
editor, 2nd ed. Hanser Publishers, 1994, pp 37-53). Typically the hard segment or component includes a crystalline or semi-crystalline
region within the cured polymer structure, whereas the soft segment or component includes
a more amorphous, non-crystalline or rubbery region. In certain embodiments, the contribution
of the structure of a component or monomer residue in a polymer to either the hardness
or softness of the resulting polymer may be determined, for example, by measuring
the Fischer microhardness of the resulting cured polymer. The physical properties
of the polymers are derived from their molecular structure and are determined by the
choice of building blocks, e.g., the choice of monomer and other reactants, additives,
the ratio of hard and soft segments, and the supramolecular structures caused by atomic
interactions between polymer chains. Materials and methods for the preparation of
polymers such as polyurethanes are described in
Ullmann's Encyclopedia of Industrial Chemistry, 5th ed., 1992, Vol. A21, pages 665-716.
[0041] For example, in the photochromic and/or dichroic materials and cured layers and coatings
described herein, it is believed that the soft segments or components of the polymeric
material or cured layers and coatings may provide an improved solubilizing environment
for the photochromic, photochromic-dichroic, and/or dichroic compound(s) to reversibly
transform from a first state to a second state, while the hard segments or components
of the polymeric material or coating provides structural integrity for the material
or coating and/or prevent migration of the transformable compounds. In one application
for photochromic and/or dichroic materials, a balance of soft and hard components
in the polymer may achieve desired benefits of a suitable cured material or cured
layer or coating, i.e., a material, layer, or coating having a Fischer microhardness
ranging from 0 to 150 Newtons/mm
2 that also exhibits good photochromic and/or dichroic response characteristics. In
another application, the photochromic and/or dichroic material may be located in a
cured polymeric material having a Fischer microhardness less than 60 Newtons/mm
2, e.g. from 0 to 59.9 Newtons/mm
2, or alternatively from 5 to 25 N/mm
2, and coated with or contained within a harder polymeric material that provides structural
strength. In a further application, the photochromic and/or dichroic material may
already be within a soft polymeric material such as a soft polymeric shell that could
be incorporated in a hard polymeric coating or material, e.g., a material having a
Fischer microhardness greater than 150 Newtons/mm
2, e.g. 200 Newtons/mm
2 or even higher.
[0042] In other embodiments, the LC compositions may further comprise a liquid crystal polymer,
including, for example a cured LCP. The liquid crystal polymer may comprise a residue
of a first liquid crystal monomer, wherein the residue of the first LC monomer is
the residue of the mesogen containing compound represented by the structure of Formula
I as defined herein. In specific embodiments, the LCP may be a copolymer wherein the
copolymer comprising the residue of the mesogen containing compound wherein the residue
of the mesogen containing compound is incorporated into the copolymer, for example,
as a co-monomer residue. That is, in certain embodiments, the residue of the mesogen
containing compound may be incorporated into the main chain of the copolymer (i.e.,
the main chain of the residue is incorporated completely into the main chain of the
copolymer) or in other embodiments, the residue of the mesogen containing compound
may be incorporated into the copolymer as a side-chain off the main chain (for example,
the residue may be bonded to the main chain by the reactive group P, with the remainder
of the residue being a side-chain of the copolymer main chain). In various embodiments,
where the residue of the mesogen containing compound, as represented by Formula I,
is incorporated into the main chain of the copolymer, the group X may be represented
by -(L)-Q, P is represented by the group Q, "w" is 1, and "z" is 1.
[0043] General synthetic methods have been developed to synthesize the scaffolds of the
mesogen containing compounds represented by Formula IV.
[0044] Referring to Figures 1 and 2, bi-mesogen containing compounds having structures corresponding
to Formula IV may be synthesized from starting hydroxy carboxylic acids that are either
commercially available or readily prepared in the lab. According to these Figures,
the bi-mesogen portion of the compound is incorporated in the latter portion of the
synthetic route. Figure 3 illustrates one approach to bond formation between free
hydroxyl groups on the linker portion to a hydroxy substituted mesogen scaffold to
form a structure according to Formula IV. This approach utilizes a Mitsunobu-type
coupling process to form ether linkages in the mesogen containing structure.
[0045] In specific embodiments, the polymer may be a block or non-block copolymer comprising
the residue of the mesogen containing compound incorporated into the copolymer. For
example, in certain embodiments, the polymer may be a block copolymer comprising the
residue of the mesogen containing compound incorporated into the copolymer, for example
as a residue incorporated into the main chain of the copolymer or as a side-chain
off the main chain of the copolymer. In certain embodiments, the block copolymer may
comprise hard blocks and soft blocks. According to these embodiments, the mesogen
containing compound may be incorporated into the hard block, the soft block, or both
the hard block and soft block. In other embodiments, the mesogen containing compound
may be dissolved (but not incorporated) into one of the blocks of the block copolymer,
such as, for example, the hard block or the soft block. In other embodiments, the
polymer may be a non-block copolymer (i.e., a copolymer that does not have large blocks
of specific monomer residues), such as a random copolymer, an alternating copolymer,
periodic copolymers, and statistical copolymers. For example, one or both of the co-monomer
residues of the copolymer may be the mesogen containing compound, as described herein.
The present disclosure is also intended to cover copolymers of more than two different
types of co-monomer residues.
[0046] According to particular embodiments, the cured LCP may be a "soft" or a "hard" polymer,
as defined herein. For example, in certain embodiments of the LCP may have a Fischer
microhardness of less than from 0 to 200 Newtons/mm
2. In other embodiments, the LCP may have an average number of at least 20 bonds between
adjacent intra- or inter-strand cross-links on a polymer backbone. That is, in a linear
sequence of bonds on a polymer backbone, there is at least a linear sequence of 20
bonds between one cross-link and the next adjacent cross-link. While not wishing to
be limited by any interpretation, it is believed that when the intra- or inter-strand
cross-links on the backbone of a polymer, such as a cured LCP described herein, are
far apart, for example, at least 20 bonds, the resulting polymer strands are more
flexible and the resulting polymer has "softer" characteristics. As described herein,
a polymer with "soft" characteristics may be desirable in certain applications, such
as to ophthalmic applications, for example, photochromic applications.
[0047] In certain embodiments of the LC compositions of the present disclosure, the LC compositions
may further comprise in addition to the at least one of photochromic compound, the
dichroic compound or the photochromic-dichroic compound; a photosensitive material,
a non-photosensitive material, and one or more additives. According to these embodiments,
the one or more additives may be a liquid crystal, a liquid crystal property control
additive, a non-linear optical material, a dye, an alignment promoter, a kinetic enhancer,
a photoinitiator, a thermal initiator, a surfactant, a polymerization inhibitor, a
solvent, a light stabilizer, a thermal stabilizer, a mold release agent, a rheology
control agent, a gelator, a leveling agent, a free radical scavenger, a coupling agent,
a tilt control additive, a block or non-block polymeric material, or an adhesion promoter.
As used herein, the term "photochromic compounds" includes thermally reversible photochromic
materials and non-thermally reversible photochromic materials, which are generally
capable of converting from a first state, for example a "clear state," to a second
state, for example a "colored state," in response to actinic radiation, and reverting
back to the first state in response to thermal energy and actinic radiation, respectively.
As used herein the term "photochromic" means having an absorption spectrum for at
least visible radiation that varies in response to at least actinic radiation. As
used herein "actinic radiation" means electromagnetic radiation, such as ultraviolet
and visible radiation that is capable of causing a response. As used herein the term
"dichroic" means capable of absorbing one of two orthogonal plane polarized components
of at least transmitted radiation more strongly than the other. As used herein, the
term "photosensitive material" includes materials that physically or chemically respond
to electromagnetic radiation, such as, for example, phosphorescent materials or fluorescent
materials. As used herein, the term "non-photosensitive materials" includes materials
that do not respond to electromagnetic radiation, such as fixed tint dyes or thermochromic
materials.
[0048] According to some embodiments the photochromic compound may comprise a photochromic
group chosen from a thermally or non-thermally reversible pyran, a thermally or non-thermally
reversible oxazine, or a thermally or non-thermally reversible fulgide. Also included
are inorganic photochromic materials. As used herein, the term "non-thermally reversible"
means adapted to switch from a first state to a second state in response to actinic
radiation, and to revert back to the first state in response to actinic radiation.
[0049] Examples of thermally reversible photochromic pyrans from which photochromic compound
may be chosen and that may be used in conjunction with various embodiments disclosed
herein include benzopyrans, naphthopyrans, e.g., naphtho[1,2-b]pyrans, naphtho[2,1-b]pyrans,
indeno-fused naphthopyrans, such as those disclosed in
U.S. Patent 5,645,767 at col. 2, line 16 to col. 12, line 57; , and heterocyclic-fused naphthopyrans, such
as those disclosed in
U.S. Patent Nos. 5,723,072 at col. 2, line 27 to col. 15, line 55;,
5,698,141 at col. 2, line 11 to col. 19, line 45;, 6,153,126 at col. 2, line 26 to col. 8,
line 60;, and
6,022,497 at col. 2, line 21 to col. 11, line 46; spiro-9-fluoreno[1,2-b]pyrans; phenanthropyrans;
quinopyrans; fluoroanthenopyrans; spiropyrans, e.g., spiro(benzindoline)naphthopyrans,
spiro(indoline)benzopyrans, spiro(indoline)naphthopyrans, spiro(indoline)quinopyrans
and spiro(indoline)pyrans. More specific examples of naphthopyrans and the complementary
organic photochromic substances are described in
U.S. Patent 5,658,501 at col. 1, line 64 to col. 13, line 17. Spiro(indoline)pyrans are also described
in the text,
Techniques in Chemistry, Volume III, "Photochromism", Chapter 3, Glenn H. Brown, Editor,
John Wiley and Sons, Inc., New York, 1971.
[0050] Examples of thermally reversible photochromic oxazines from which the photochromic
compounds may be chosen and that may be used in conjunction with various embodiments
disclosed herein include benzoxazines, naphthoxazines, and spiro-oxazines, e.g., spiro(indoline)naphthoxazines,
spiro(indoline)pyridobenzoxazines, spiro(benzindoline) pyridobenzoxazines, spiro(benzindoline)naphthoxazines,
spiro(indoline)benzoxazines, spiro(indoline)fluoranthenoxazine, and spiro(indoline)quinoxazine.
[0051] Examples of thermally reversible photochromic fulgides from which the photochromic
compounds may be chosen and that may be used in conjunction with various embodiments
disclosed herein include: fulgimides, and the 3-furyl and 3-thienyl fulgides and fulgimides,
which are disclosed in
U.S. Patent 4,931,220 at column 2, line 51 to column 10, line 7, and mixtures of any of the aforementioned
photochromic materials/compounds. Examples of non-thermally reversible photochromic
compounds from which the photochromic compounds may be chosen and that may be used
in conjunction with various embodiments disclosed herein include the photochromic
compounds disclosed in
US Patent Application Publication 2005/0004361 at paragraphs [0314] to [0317].
[0052] In certain embodiments, the photochromic compound may be an inorganic photochromic
compound. Examples of suitable include crystallites of silver halide, cadmium halide
and/or copper halide. Other Examples of inorganic photochromic materials may be prepared
by the addition of europium(II) and/or cerium(II) to a mineral glass, such as a soda-silica
glass. According to one embodiment, the inorganic photochromic materials may be added
to molten glass and formed into particles that are incorporated into the compositions
of the present disclosure to form microparticles comprising such particulates. The
glass particulates may be formed by any of a number of various methods known in the
art. Suitable inorganic photochromic materials are further described in
Kirk Othmer, Encyclopedia of Chemical Technology, 4th ed., volume 6, pages 322-325.
[0053] Other embodiments of the compositions may comprise a photosensitive material, including
luminescent dyes, such as a phosphorescent dye or a fluorescent dye. As known to those
skilled in the art, after activation the phosphorescent dyes and fluorescent dyes
emit visible radiation when an atom or molecule passes from a higher to a lower electronic
state. One difference between the two dye types is that the emission of luminescence
after exposure to radiation from the fluorescent dye occurs sooner than that from
a phosphorescent dye.
[0054] Fluorescent dyes known to those skilled in the art may be used as photosensitive
materials in various embodiments of the present disclosure. For a listing of various
fluorescent dyes, see,
Haugland, R. P., Molecular Probes Handbook for Fluorescent Probes and Research Chemicals,
6th ed., 1996. Examples of fluorescent dyes include anthracenes tetracenes, pentacenes, rhodamines,
benzophenones, coumarins, fluoresceins, perylenes, and mixtures thereof.
[0055] Phosphorescent dyes known to those skilled in the art may be used as photosensitive
materials in various embodiments of the present disclosure. Suitable examples of phosphorescent
dyes include, metal-ligand complexes such as tris(2-phenylpyridine)iridium [Ir(ppy)
3] and 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platimum(II) [PtOEP]; and organic
dyes such as eosin (2',4',5',7'-tetrabromofluorescein), 2,2'-bipyridine and erthrosin
(2',4',5',7'-tetraiodofluorescein).
[0056] Examples of non-photosensitive materials suitable for use in the compositions of
the present disclosure include fixed-tint dyes. Examples of suitable fixed-tint dyes
may include nitrobenzene dyes, azo dyes, anthraquinone dyes, naphthoquinone dyes,
benzoquinone dyes, phenothiazine dyes, indigoid dyes, xanthene dyes, pheanthridine
dyes, phthalocyanin dyes and dyes derived from triarylmethane. These fixed-tint dyes
may be used alone or as mixtures with other fixed-tint dyes or other chromophoric
compounds (such as photochromic compounds).
[0057] Suitable examples of dyes used with suitable other chemicals to make thermochromic
materials include substituted phenylmethanes and fluorans, such as 3,3'-dimethoxyfluoran
(yellow); 3-chloro-6-phenylaminofluoran (orange); 3-diethylamino-6-methyl-7-chlorofluoran
(vermilion); 3-diethyl-7,8-benzofluoran (pink); Crystal Violet lactone (blue); 3,3',3"-tris(p-dimethylaminophenyl)phthalide
(purplish blue); Malachite Green lactone (green); 3,3;-bis(pdimethylaminophenyl)phthalide
(green); 3-diethylmaino-6-methyl-7-phenylaminofluoran (black), indolyl phthalides,
spiropyrans, coumarins, fulgides, etc. Further, thermochromic materials may also include
cholesteric liquid crystals and mixtures of cholesteric liquid crystals and nematic
liquid crystals.
[0058] According to one specific, embodiment, the photochromic compound may comprise at
least two photochromic groups, wherein the photochromic groups are linked to one another
via linking group substituents on the individual photochromic groups. For example,
the photochromic groups can be polymerizable photochromic groups or photochromic groups
that are adapted to be compatible with a host material ("compatibilized photochromic
group"). Examples of polymerizable photochromic groups which can be chosen and that
are useful in conjunction with various embodiments disclosed herein are disclosed
in
U.S. Patent 6,113,814 at column 2, line 24 to column 22, line 7. Examples of compatiblized photochromic
groups which can be chosen and that are useful in conjunction with various embodiments
disclosed herein are disclosed in
U.S. Patent 6,555,028 at column 2, line 40 to column 24, line 56.
[0059] Other suitable photochromic groups and complementary photochromic groups are described
in
U.S. Patents 6,080,338 at column 2, line 21 to column 14, line 43;
6,136,968 at column 2, line 43 to column 20, line 67; 6,296,785 at column 2, line 47 to column
31, line 5; 6,348,604 at column 3, line 26 to column 17, line 15; 6,353,102 at column
1, line 62 to column 11, line 64; and 6,630,597 at column 2, line 16 to column 16,
line 23.
[0060] As set forth above, in certain embodiments the photochromic compound may be a photochromic
pyran. According to these embodiments, the photochromic compound may be represented
by Formula IX:

[0061] With reference to Formula IX, A is a substituted or unsubstituted aromatic ring or
a substituted or unsubstituted fused aromatic ring chosen from: naphtho, benzo, phenanthro,
fluorantheno, antheno, quinolino, thieno, furo, indolo, indolino, indeno, benzofuro,
benzothieno, thiopheno, indeno-fused naphtho, heterocyclic-fused naphtho, and heterocyclic-fused
benzo. According to these embodiments, the possible substituents on the aromatic or
fused aromatic ring are disclosed in
U.S. Patent Nos. 5,458,814;
5,466,398;
5,514,817;
5,573,712;
5,578,252;
5,637,262;
5,650,098;
5,651,923;
5,698,141;
5,723,072;
5,891,368;
6,022,495;
6,022,497;
6,106,744;
6,149,841;
6,248,264;
6,348,604;
6,736998;
7,094,368,
7,262,295 and
7,320,826. According to Formula IX, "i" may be the number of substituent(s) R' attached to
ring A, and may range from 0 to 10. Further, with reference to Formula IX, B and B'
may each independently represent a group chosen from:
- a metallocenyl group (such as those described in U.S. Patent Application Publication 2007/0278460 at paragraph [0008] to [0036]);
- an aryl group that is mono-substituted with a reactive substituent or a compatiblizing
substituent (such as those discussed in U.S. Patent Application Publication 2007/0278460 at paragraph [0037] to [0059]);
- 9-julolidinyl, an unsubstituted, mono-, di- or tri-substituted aryl group chosen from
phenyl and naphthyl, an unsubstituted, mono- or di-substituted heteroaromatic group
chosen from pyridyl, furanyl, benzofuran-2-yl, benzofuran-3-yl, thienyl, benzothien-2-yl,
benzothien-3-yl, dibenzofuranyl, dibenzothienyl, carbazoyl, benzopyridyl, indolinyl
and fluorenyl, wherein the aryl and heteroaromatic substituents are each independently:
hydroxy, aryl, mono- or di-(C1-C12)alkoxyaryl, mono- or di-(C1-C12)alkylaryl, haloaryl, C3-C7 cycloalkylaryl, C3-C7 cycloalkyl, C3-C7 cycloalkyloxy, C3-C7 cycloalkyloxy(C1-C12)alkyl, C3-C7 cycloalkyloxy(C1-C12)alkoxy, aryl(C1-C12)alkyl, aryl(C1-C12)alkoxy, aryloxy, aryloxy(C1-C12)alkyl, aryloxy(C1-C12)alkoxy, mono- or di-(C1-C12)alkylaryl(C1-C12)alkyl, mono- or di-(C1-C12)alkoxyaryl(C1-C12)alkyl, mono- or di-(C1-C12)alkylaryl(C1-C12)alkoxy, mono- or di-(C1-C12)alkoxyaryl(C1-C12)alkoxy, amino, mono- or di-(C1-C12)alkylamino, diarylamino, piperazino, N-(C1-C12)alkylpiperazino, N-arylpiperazino, aziridino, indolino, piperidino, morpholino, thiomorpholino,
tetrahydroquinolino, tetrahydroisoquinolino, pyrrolidino, C1-C12 alkyl, C1-C12 haloalkyl, C1-C12 alkoxy, mono(C1-C12 )alkoxy(C1-C12 )alkyl, acryloxy, methacryloxy, halogen or -C(=O)R1, wherein R1 represents a group, such as, -OR2, -N(R3)R4, piperidino or morpholino, wherein R2 represents a group, such as, allyl, C1-C6 alkyl, phenyl, mono(C1-C6)alkyl substituted phenyl, mono(C1-C6)alkoxy substituted phenyl, phenyl(C1-C3)alkyl, mono(C1-C6)alkyl substituted phenyl(C1-C3)alkyl, mono(C1-C6)alkoxy substituted phenyl(C1-C3)alkyl, C1-C6 alkoxy(C2-C4)alkyl or C1-C6 haloalkyl, and R3 and R4 each independently represents a group, such as, C1-C6 alkyl, C5-C7 cycloalkyl or a substituted or an unsubstituted phenyl, wherein said phenyl substituents
are each independently C1-C6 alkyl or C1-C6 alkoxy;
an unsubstituted or mono-substituted group chosen from pyrazolyl, imidazolyl, pyrazolinyl,
imidazolinyl, pyrrolidino, phenothiazinyl, phenoxazinyl, phenazinyl and acridinyl,
wherein said substituents are each independently C1-C12 alkyl, C1-C12 alkoxy, phenyl or halogen;
a 4-substituted phenyl, the substituent being a dicarboxylic acid residue or derivative
thereof, a diamine residue or derivative thereof, an amino alcohol residue or derivative
thereof, a polyol residue or derivative thereof, -(CH2)-, -(CH2)k- or -[O-(CH2)k]q-, wherein "k" represents an integer ranging from 2 to 6 and "q" represents an integer
ranging from 1 to 50, and wherein the substituent is connected to an aryl group of
another photochromic material;
a group represented by:

wherein W represents a group, such as, -CH
2- or oxygen; Y represents a group, such as, oxygen or substituted nitrogen, provided
that when Y represents substituted nitrogen, W represents -CH
2-, the substituted nitrogen substituents being hydrogen, C
1-C
12 alkyl or C
1-C
12 acyl; each R
5 independently represents a group, such as, C
1-C
12 alkyl, C
1-C
12 alkoxy, hydroxy or halogen; R
6 and R
7 each independently represent a group, such as, hydrogen or C
1-C
12 alkyl; and "j" represents an integer ranging from 0 to 2; or
a group represented by:

wherein R
8 represents a group, such as, hydrogen or C
1-C
12 alkyl, and R
9 represents a group, such as, an unsubstituted, mono- or di-substituted naphthyl,
phenyl, furanyl or thienyl, wherein said naphthyl, phenyl, furanyl and thienyl substituents
are each independently C
1-C
12 alkyl, C
1-C
12 alkoxy or halogen. Alternatively, B and B' may represent groups that together form
a fluoren-9-ylidene or mono- or di-substituted fluoren-9-ylidene, each of said fluoren-9-ylidene
substituents independently being C
1-C
12 alkyl, C
1-C
12 alkoxy or halogen.
[0062] Further, with reference to Formula IX, R' may be a substituent on a ring in Formula
IX, wherein if R' is a substituent on an sp
3 hybridized carbon, each R' may be independently selected from: a metallocenyl group;
a reactive substituent or a compatiblizing substituent; perhalo(C
1-C
10)alkyl, a perhalo(C
2-C
10)alkenyl, a perhalo(C
3-C
10)alkynyl, a perhalo(C
1-C
10)alkoxy or a perhalo(C
3-C
10)cycloalkyl; a group represented by -O(CH
2)
a(CJ
2)
bCK
3, wherein K is a halogen, J is hydrogen or halogen, "a" is an integer ranging from
1 to 10, and "b" is an integer ranging from 1 to 10; a silicon-containing group represented
by one of

wherein R
10, R
11, and R
12 are each independently C
1-C
10 alkyl, C
1-C
10 alkoxy or phenyl; hydrogen, hydroxy, C
1-C
6 alkyl, chloro, fluoro, C
3-C
7 cycloalkyl, allyl or C
1-C
8 haloalkyl; morpholino, piperidino, pyrrolidino, an unsubstituted, mono- or di-substituted
amino, wherein said amino substituents are each independently C
1-C
6 alkyl, phenyl, benzyl or naphthyl; an unsubstituted, mono-, di- or tri-substituted
aryl group chosen from phenyl, naphthyl, benzyl, phenanthryl, pyrenyl, quinolyl, isoquinolyl,
benzofuranyl, thienyl, benzothienyl, dibenzofuranyl, dibenzothienyl, carbazolyl or
indolyl, wherein the aryl group substituents are each independently halogen, C
1-C
6 alkyl or C
1-C
6 alkoxy; -C(=O)R
13, wherein R
13 is hydrogen, hydroxy, C
1-C
6 alkyl, C
1-C
6 alkoxy, amino, mono- or di-(C
1-C
6)alkylamino, morpholino, piperidino, pyrrolidino, an unsubstituted, mono- or di-substituted
phenyl or naphthyl, an unsubstituted, mono- or di-substituted phenoxy, an unsubstituted,
mono- or di-substituted phenylamino, wherein said phenyl, naphthyl, phenoxy, and phenylamino
substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy; -OR
14, wherein R
14 is C
1-C
6 alkyl, phenyl(C
1-C
3)alkyl, mono(C
1-C
6)alkyl substituted phenyl(C
1-C
3)alkyl, mono(C
1-C
6)alkoxy substituted phenyl(C
1-C
3)alkyl, C
1-C
6 alkoxy(C
2-C
4)alkyl, C
3-C
7 cycloalkyl, mono(C
1-C
4)alkyl substituted C
3-C
7 cycloalkyl, C
1-C
8 chloroalkyl, C
1-C
8 fluoroalkyl, allyl or C
1-C
6 acyl, -CH(R
15)R
16, wherein R
15 is hydrogen or C
1-C
3 alkyl, and R
16 is -CN, -CF
3 or -COOR
17, wherein R
17 is hydrogen or C
1-C
3 alkyl, or -C(=O)R
18, wherein R
18 is hydrogen, C
1-C
6 alkyl, C
1-C
6 alkoxy, amino, mono- or di-(C
1-C
6)alkylamino, an unsubstituted, mono- or di-substituted phenyl or naphthyl, an unsubstituted,
mono- or di-substituted phenoxy or an unsubstituted, mono- or di-substituted phenylamino,
wherein said phenyl, naphthyl, phenoxy and phenylamino substituents are each independently
C
1-C
6 alkyl or C
1-C
6 alkoxy; a 4-substituted phenyl, the substituent being a dicarboxylic acid residue
or derivative thereof, a diamine residue or derivative thereof, an amino alcohol residue
or derivative thereof, a polyol residue or derivative thereof, -(CH
2)-, -(CH
2)
k- or -[O-(CH
2)
k]
q-, wherein "k" is an integer ranging from 2 to 6 and "q" is an integer ranging from
1 to 50, and wherein the substituent is connected to an aryl group on another photochromic
material; -CH(R
19)
2, wherein R
19 is -CN or -COOR
20, wherein R
20 is hydrogen, C
1-C
6 alkyl, C
3-C
7 cycloalkyl, phenyl(C
1-C
3)alkyl, mono(C
1-C
6)alkyl substituted phenyl(C
1-C
3)alkyl, mono(C
1-C
6)alkoxy substituted phenyl(C
1-C
3)alkyl or an unsubstituted, mono- or di-substituted phenyl or naphthyl, wherein said
phenyl and naphthyl substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy; -CH(R
21)R
22, wherein R
21 is hydrogen, C
1-C
6 alkyl or an unsubstituted, mono- or di-substituted phenyl or naphthyl, wherein said
phenyl and naphthyl substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy, and R
22 is -C(=O)OR
23, -C(=O)R
24 or -CH
2OR
25, wherein R
23 is hydrogen, C
1-C
6 alkyl, C
3-C
7 cycloalkyl, phenyl(C
1-C
3)alkyl, mono(C
1-C
6)alkyl substituted phenyl(C
1-C
3)alkyl, mono(C
1-C
6)alkoxy substituted phenyl(C
1-C
3)alkyl or an unsubstituted, mono- or di-substituted phenyl or naphthyl, wherein said
phenyl and naphthyl substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy, R
24 is hydrogen, C
1-C
6 alkyl, amino, mono(C
1-C
6)alkylamino, di(C
1-C
6) alkylamino, phenylamino, diphenylamino, (mono- or di-(C
1-C
6)alkyl substituted phenyl)amino, (mono- or di-(C
1-C
6)alkoxy substituted phenyl)amino, di(mono- or di-(C
1-C
6)alkyl substituted phenyl)amino, di(mono- or di-(C
1-C
6)alkoxy substituted phenyl)amino, morpholino, piperidino or an unsubstituted, mono-
or di-substituted phenyl or naphthyl, wherein said phenyl or naphthyl substituents
are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy, and R
25 is hydrogen, -C(=O)R
23, C
1-C
6 alkyl, C
1-C
3 alkoxy (C
1-C
6)alkyl, phenyl(C
1-C
6)alkyl, mono-alkoxy substituted phenyl(C
1-C
6)alkyl or an unsubstituted, mono- or di-substituted phenyl or naphthyl, wherein said
phenyl or naphthyl substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy; or two R' groups on the same atom together form an oxo group, a spiro-carbocyclic
group containing 3 to 6 carbon atoms or a spiro-heterocyclic group containing 1 to
2 oxygen atoms and 3 to 6 carbon atoms including the spirocarbon atom, said spiro-carbocyclic
and spiro-heterocyclic groups being annellated with 0, 1 or 2 benzene rings; or
when R' is a substituent on an sp
2 hybridized carbon, each R' may be independently: hydrogen; C
1-C
6 alkyl; chloro; fluoro; bromo; C
3-C
7 cycloalkyl; an unsubstituted, mono- or di-substituted phenyl, wherein said phenyl
substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy; -OR
26 or -OC(=O)R
26 wherein R
26 is hydrogen, amine, alkylene glycol, polyalkylene glycol, C
1-C
6 alkyl, phenyl(C
1-C
3)alkyl, mono(C
1-C
6)alkyl substituted phenyl(C
1-C
6)alkyl, mono(C
1-C
6)alkoxy substituted phenyl(C
1-C
3)alkyl, (C
1-C
6)alkoxy(C
2-C
4)alkyl, C
3-C
7 cycloalkyl, mono(C
1-C
4)alkyl substituted C
3-C
7 cycloalkyl or an unsubstituted, mono- or di-substituted phenyl, wherein said phenyl
substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy; a reactive substituent or a compatiblizing substituent; a 4-substituted phenyl,
said phenyl substituent being a dicarboxylic acid residue or derivative thereof, a
diamine residue or derivative thereof, an amino alcohol residue or derivative thereof,
a polyol residue or derivative thereof, -(CH
2)-, -(CH
2)
k- or -[O-(CH
2)
k]
q-, wherein "k" is an integer ranging from 2 to 6, and "q" is an integer ranging from
1 to 50, and wherein the substituent is connected to an aryl group on another photochromic
material; -N(R
27)R
28, wherein R
27 and R
28 are each independently hydrogen, C
1-C
8 alkyl, phenyl, naphthyl, furanyl, benzofuran-2-yl, benzofuran-3-yl, thienyl, benzothien-2-yl,
benzothien-3-yl, dibenzofuranyl, dibenzothienyl, benzopyridyl, fluorenyl, C
1-C
8 alkylaryl, C
3-C
8 cycloalkyl, C
4-C
16 bicycloalkyl, C
5-C
20 tricycloalkyl or C
1-C
20 alkoxy(C
1-C
6)alkyl, or R
27 and R
28 come together with the nitrogen atom to form a C
3-C
20 hetero-bicycloalkyl ring or a C
4-C
20 hetero-tricycloalkyl ring; a nitrogen containing ring represented by:

wherein each -V- is independently chosen for each occurrence from -CH
2-, -CH(R
29)-, -C(R
29)
2-, -CH(aryl)-, -C(aryl)
2- and -C(R
29)(aryl)-, wherein each R
29 is independently C
1-C
6 alkyl and each aryl is independently phenyl or naphthyl; -U- is -V-, -O-, -S-, -S(O)-,
-SO
2- -NH-, -N(R
29)- or - N(aryl)-; "s" is an integer ranging from 1 to 3; and "r" is an integer ranging
from 0 to 3, provided that if" "r is 0 then -U- is the same as -V-; a group represented
by:

wherein each R
30 is independently C
1-C
6 alkyl, C
1-C
6 alkoxy, fluoro or chloro; R
31, R
32 and R
33 are each independently hydrogen, C
1-C
6 alkyl, phenyl or naphthyl, or R
31 and R
32 together form a ring of 5 to 8 carbon atoms; and "p" is an integer ranging from 0
to 3; or a substituted or an unsubstituted C
4-C
18 spirobicyclic amine or a substituted or an unsubstituted C
4-C
18 spirotricyclic amine, wherein said substituents are each independently aryl, C
1-C
6 alkyl, C
1-C
6 alkoxy or phenyl(C
1-C
6)alkyl;
or R' may be a metallocenyl group; perfluoroalkyl or perfluoroalkoxy; -C(=O)R
34 or -SO
2R
34, wherein each R
34 is independently hydrogen, C
1-C
6 alkyl, -OR
35 or -NR
36R
37, wherein R
35, R
36 and R
37 are each independently hydrogen, C
1-C
6 alkyl, C
5-C
7 cycloalkyl, alkylene glycol, polyalkylene glycol or an unsubstituted, mono- or di-substituted
phenyl, wherein said phenyl substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy; -C(=C(R
38)
2)R
39, wherein each R
38 is independently -C(=O)R
34, -OR
35, -OC(=O)R
35, -NR
36R
37, hydrogen, halogen, cyano, C
1-C
6 alkyl, C
5-C
7 cycloalkyl, alkylene glycol, polyalkylene glycol or an unsubstituted, mono- or di-substituted
phenyl, wherein said phenyl substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy, and R
39 is hydrogen, C
1-C
6 alkyl, C
5-C
7 cycloalkyl, alkylene glycol, polyalkylene glycol or an unsubstituted, mono- or di-substituted
phenyl, wherein said phenyl substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy; or -C≡CR
40 or-C≡N wherein R
40 is -C(=O)R
34, hydrogen, C
1-C
6 alkyl, C
5-C
7 cycloalkyl or an unsubstituted, mono- or di-substituted phenyl, wherein said phenyl
substituents are each independently C
1-C
6 alkyl or C
1-C
6 alkoxy; or a least one pair of adjacent R' groups together form a group represented
by:

wherein D and D' are each independently oxygen or the group -NR
27-; or two R' groups on adjacent atoms come together form an aromatic or heteroaromatic
fused group, said fused group being benzo, indeno, dihydronaphthalene, indole, benzofuran,
benzopyran or thianaphthene.
[0063] In other embodiments, the LC compositions of the present disclosure may comprise
a dichroic compound. Suitable dichroic compounds are described in detail in Patent
7,097,303 at column 7, lines 6 to 60. Other examples of suitable conventional dichroic compounds
include azomethines, indigoids, thioindigoids, merocyanines, indans, quinophthalonic
dyes, perylenes, phthaloperines, triphenodioxazines, indoloquinoxalines, imidazo-triazines,
tetrazines, azo and (poly)azo dyes, benzoquinones, naphthoquinones, anthroquinone
and (poly)anthroquinones, anthropyrimidinones, iodine and iodates. In another embodiment,
the dichroic material can be a polymerizable dichroic compound. That is, according
to this embodiment, the dichroic material can comprise at least one group that is
capable of being polymerized (i.e., a "polymerizable group" or "reactive group").
For example in one embodiment the at least one dichroic compound can have at least
one alkoxy, polyalkoxy, alkyl, or polyalkyl substituent terminated with at least one
polymerizable group. As used herein the term "dichroic" means capable absorbing one
of two orthogonal plane polarized components of at least transmitted radiation more
strongly than the other. As used herein, the terms "linearly polarize" or "linearly
polarization" mean to confine the vibrations of the electric vector of light waves
to one direction. Accordingly, dichroic dyes are capable of absorbing one of two orthogonal
plane polarized components of transmitted radiation more strongly than the other,
thereby resulting in linear polarization of the transmitted radiation. However, while
dichroic dyes are capable of preferentially absorbing one of two orthogonal plane
polarized components of transmitted radiation, if the molecules of the dichroic dye
are not aligned, no net linear polarization of transmitted radiation will be achieved.
That is, due to the random positioning of the molecules of the dichroic dye, selective
absorption by the individual molecules can cancel each other such that no net or overall
linear polarizing effect is achieved. Thus, it is generally necessary to align the
molecules of the dichroic dye in order to achieve a net linear polarization. An alignment
facility such as described in
U.S. Patent Application Publication 2005/0003107 at paragraphs [0008] to [0126], may be used to facilitate the positioning of an optically
anisotropic dye, such as a dichroic dye, thereby achieving a desired optical property
or effect.
[0064] Still other embodiments of the LC compositions herein may comprise a photochromic-dichroic
compound. As used herein the term "photochromic-dichroic" means displaying both photochromic
and dichroic (i.e., linearly polarizing) properties under certain conditions, which
properties are at least detectible by instrumentation. Accordingly, "photochromic-dichroic
compounds" are compounds displaying both photochromic and dichroic (i.e., linearly
polarizing) properties under certain conditions, which properties are at least detectible
by instrumentation. Thus, photochromic-dichroic compounds have an absorption spectrum
for at least visible radiation that varies in response to at least actinic radiation
and are capable of absorbing one of two orthogonal plane polarized components of at
least transmitted radiation more strongly than the other. Additionally, as with conventional
photochromic compounds discussed above, the photochromic-dichroic compounds disclosed
herein can be thermally reversible. That is, the photochromic-dichroic compounds can
switch from a first state to a second state in response to actinic radiation and revert
back to the first state in response to thermal energy.
[0065] Further, according to various embodiments disclosed herein, the mesogen containing
material can be adapted to allow the at least one photochromic compound, dichroic
compound, or photochromic-dichroic compound to switch from a first state to the second
state at a desired rate. Generally speaking conventional photochromic/dichroic compounds
can undergo a transformation from one isomeric form to another in response to actinic
radiation, with each isomeric form having a characteristic absorption spectrum and/or
polarization characteristic. The photochromic compound, dichroic compound, or photochromic-dichroic
compounds according to various embodiments disclosed herein undergo a similar isomeric
transformation. The rate or speed at which this isomeric transformation (and the reverse
transformation) occurs depends, in part, upon the properties of the cured layer comprising
the mesogen containing compound surrounding the photochromic compound, dichroic compound,
or photochromic-dichroic compound (that is, the "host"). It is believed by the inventors
the rate of transformation of the photochromic/dichroic compound(s) will depend, in
part, upon the flexibility of the chain segments of the host, that is, the mobility
or viscosity of the chain segments of the host. In particular it is believed that
the rate of transformation of the photochromic compound, dichroic compound, or photochromic-dichroic
compound will generally be faster in hosts having flexible chain segments than in
hosts having stiff or rigid chain segments. Therefore, according to certain embodiments
disclosed herein, wherein the at least partial layer comprising a composition comprising
the mesogen containing compound is a host, the composition can be adapted to allow
the photochromic compound, dichroic compound, or photochromic-dichroic compound to
transform between various isomeric states at desired rates. For example, the composition
can be adapted by adjusting one or more of the molecular weight and the cross-link
density of the mesogen containing compound or residue thereof.
[0066] For example, according to various embodiments disclosed herein, the at least one
photochromic-dichroic compound can have a first state having a first absorption spectrum,
a second state having a second absorption spectrum that is different from the first
absorption spectrum, and can be adapted to switch from the first state to the second
state in response to at least actinic radiation and to revert back to the first state
in response to thermal energy. Further, the photochromic-dichroic compound can be
dichroic (i.e., linearly polarizing) in one or both of the first state and the second
state. For example, although not required, the photochromic-dichroic compound can
be linearly polarizing in an activated state and non-polarizing in the bleached or
faded (i.e., not activated) state. As used herein, the term "activated state" refers
to the photochromic-dichroic compound when exposed to sufficient actinic radiation
to cause the at least a portion of the photochromic-dichroic compound to switch from
a first state to a second state. Further, although not require, the photochromic-dichroic
compound can be dichroic in both the first and second states. For example, the photochromic-dichroic
compound can linearly polarize visible radiation in both the activated state and the
bleached state. Further, the photochromic-dichroic compound can linearly polarize
visible radiation in an activated state, and can linearly polarize UV radiation in
the bleached state. Examples of suitable photochromic-dichroic compounds that may
be included in the LC compositions described herein include those disclosed in
U.S. Patent Application Publication 2005/0012998 at paragraphs [0089] to [0339]. In addition, a general structure for certain photochromic
dichroic compounds is presented in
U.S. Patent No. 7,342,112 at column 5, line 35 to column 31, line 3 and Table V spanning columns 97-102.
[0067] For example, it is contemplated that the photochromic compounds and/or photochromic-dichroic
compounds disclosed herein can be used alone or in conjunction with another conventional
organic photochromic compound (as discussed above), in amounts or ratios such that
the LC compositions into which the photochromic or photochromic-dichroic compounds
are incorporated, or onto which the LC compositions are applied (for example, the
substrate), can exhibit a desired color or colors, either in an activated or a "bleached"
state. Thus the amount of the photochromic or photochromic-dichroic compounds used
is not critical provided that a sufficient amount is present to produce a desired
photochromic effect. As used herein, the term "photochromic amount" refers to the
amount of the photochromic or photochromic-dichroic compound necessary to produce
the desired photochromic effect.
[0068] The LC compositions and other articles according to various embodiments disclosed
herein can comprise any amount of the photochromic compound, dichroic compound and/or
photochromic-dichroic necessary to achieve the desired optical properties photochromic
properties and dichroic properties.
[0069] According to specific embodiments of the LC compositions, the compositions may further
comprise an additive selected from a liquid crystal, a liquid crystal property control
agent, a non-linear optical material, a dye, an alignment promoter, a kinetic enhancer,
a photoinitiator, a thermal initiator, a surfactant, a polymerization inhibitor, a
solvent, a light stabilizer (such as ultraviolet light absorbers and light stabilizers
such as hindered amine light stabilizers (HALS)), a thermal stabilizer, a mold release
agent, a rheology control agent, a gelator, a leveling agent (such as a surfactant),
a free radical scavenger, or an adhesion promoter (such as hexane diol diacrylate
and coupling agents).
[0070] Liquid crystal materials used herein may be chosen from liquid crystal polymers,
liquid crystal pre-polymers, and liquid crystal monomers. As used herein the term
"pre-polymer" means partially polymerized materials.
[0071] Liquid crystal monomers that are suitable for use in conjunction with various embodiments
disclosed herein include mono-functional as well as multi-functional liquid crystal
monomers. Further, according to various embodiments disclosed herein, the liquid crystal
monomer can be a cross-linkable liquid crystal monomer, and can further be a photocross-linkable
liquid crystal monomer. As used herein the term "photocross-linkable" means a material,
such as a monomer, a pre-polymer or a polymer, that can be cross-linked on exposure
to actinic radiation.
[0072] Examples of cross-linkable liquid crystal monomers suitable for use according to
various embodiments disclosed herein include liquid crystal monomers having functional
groups chosen from acrylates, methacrylates, allyl, allyl ethers, alkynes, amino,
anhydrides, epoxides, hydroxides, isocyanates, blocked isocyanates, siloxanes, thiocyanates,
thiols, urea, vinyl, vinyl ethers and blends thereof. Examples of photocross-linkable
liquid crystal monomers suitable for use according to various embodiments disclosed
herein include liquid crystal monomers having functional groups chosen from acrylates,
methacrylates, alkynes, epoxides, thiols, and blends thereof. Other suitable cross-linking
functional groups will be known to those with ordinary skill in the art.
[0073] Liquid crystal polymers and pre-polymers that are suitable for use in conjunction
with various embodiments disclosed herein include thermotropic liquid crystal polymers
and pre-polymers, and lyotropic liquid crystal polymers and pre-polymers. Further,
the liquid crystal polymers and pre-polymers can be main-chain polymers and pre-polymers
or side-chain polymers and pre-polymers. Additionally, according to various embodiments
disclosed herein, the liquid crystal polymer or pre-polymer can be cross-linkable,
and further can be photocross-linkable.
[0074] Examples of suitable liquid crystal polymers and pre-polymers that are suitable for
use according to various embodiments disclosed herein include main-chain and side-chain
polymers and pre-polymers having functional groups chosen from acrylates, methacrylates,
allyl, allyl ethers, alkynes, amino, anhydrides, epoxides, hydroxides, isocyanates,
blocked isocyanates, siloxanes, thiocyanates, thiols, urea, vinyl, vinyl ethers, and
blends thereof. Examples of photocross-linkable liquid crystal polymers and pre-polymers
that are suitable for use according to various embodiments disclosed herein include
those polymers and pre-polymers having functional groups chosen from acrylates, methacrylates,
alkynes, epoxides, thiols, and blends thereof.
[0075] In certain embodiments, one or more surfactants may be used. Surfactants include
materials otherwise known as wetting agents, anti-foaming agents, emulsifiers, dispersing
agents, leveling agents etc. Surfactants can be anionic, cationic and nonionic, and
many surfactants of each type are available commercially. Examples of nonionic surfactants
that may be used include ethoxylated alkyl phenols, such as the IGEPAL
® DM surfactants or octyl-phenoxypolyethoxyethanol sold as TRITON
® X-1 00, an acetylenic diol such as 2,4,7,9-tetramethyl-5-decyne-4,7-diol sold as
SURFYNOL
® 104, ethoxylated acetylenic diols, such as the SURFYNOL
®400 surfactant series, fluoro-surfactants, such as the FLUORAD
® fluorochemical surfactant series, and capped nonionics such as the benzyl capped
octyl phenol ethoxylates sold as TRITON
® CF87, the propylene oxide capped alkyl ethoxylates, which are available as the PLURAFAC
® RA series of surfactants, octylphenoxyhexadecylethoxy benzyl ether, polyether modified
dimethylpolysiloxane copolymer in solvent sold as BYK
®-306 additive by Byk Chemie and mixtures of such recited surfactants.
[0076] Embodiments of non-linear optical (NLO) materials may include substantially any organic
material that exhibits non-linear optical properties and forms crystals, which are
currently available or may be synthesized in the future. Examples include the following
organic compounds: N-(4-nitrophenyl)-(L)-prolinol (NPP); 4-N,N-dimethylamino-4'-N'-methyl-stilbazolium
tosylate (DAST); 2-methyl-4-nitroaniline (MNA); 2-amino-5-nitropyridine (2A5NP); p-chlorophenylurea
(PCPU); and 4-(N,N-dimethylamino)-3-acetamidonitrobenzene (DAN). Further examples
of suitable NLO materials are disclosed in
U.S. Patent No. 6,941,051 at column 4, lines 4-37.
[0077] Examples of thermal stabilizers may include a basic nitrogen-containing compound
for example, biurea, allantoin or a metal salt thereof, a carboxylic acid hydrazide,
e.g., an aliphatic or aromatic carboxylic acid hydrazide, a metal salt of an organic
carboxylic acid, an alkali or alkaline earth metal compound, a hydrotalcite, a zeolite
and an acidic compound (e.g., a boric acid compound, a nitrogen-containing cyclic
compound having a hydroxyl group, a carboxyl group-containing compound, a (poly)phenol,
butylated hydroxytoluene, and an aminocarboxylic acid) or mixtures thereof.
[0078] Examples of mold release agents include esters of long-chain aliphatic acids and
alcohols such as pentaerythritol, guerbet alcohols, long-chain ketones, siloxanes,
alpha.-olefin polymers, long-chain alkanes and hydrocarbons having 15 to 600 carbon
atoms.
[0079] Rheology control agents are thickeners that are typically powders that may be inorganic,
such as silica, organic such as microcrystalline cellulose or particulate polymeric
materials. Gelators or gelling agents are often organic materials that can also affect
the thixotropy of the material in which they are added. Examples of suitable gelators
or gelling agents include natural gums, starches, pectins, agar-agar, and gelatins.
Gelators or gelling agents may often be based on polysaccharides or proteins.
[0080] Free radical scavengers include synthetic pseudopeptides resistant to hydrolysis
such as Carcinine hydrochloride; lipoamino acids such as L-lysine lauroylmethionine;
plant extracts containing multi-enzymes; natural tocopherol and related compounds
as well as compounds containing an active hydrogen such as -OH, -SH, or -NRH group.
Further examples of free radical scavengers are chosen from the group of sterically
hindered amines (HALS=hindered amine light stabilizer) which, unlike customary light
protection agents, are not based on the absorption of the irradiated light or on the
quenching of the absorbed light, but essentially on the ability to scavenge or to
replace free radicals and hydroperoxides formed during the photodegradation of polymeric
materials and antioxidants.
[0081] Adhesion promoters include adhesion promoting organo-silane materials, such as aminoorganosilane
materials, silane coupling agents, organic titanate coupling agents and organic zirconate
coupling agents described in
U.S. Patent Application Publication 2004/0207809 at paragraphs [0033] to [0042]. Further examples of adhesion promoters include zirco-aluminate
adhesion promoting compounds that are commercially available from Rhone-Poulenc. Preparation
of aluminum-zirconium complexes is described in the
U.S. Patent Nos. 4,539,048 and
4,539,049. These patents describe zirco-aluminate complex reaction products corresponding to
the empirical formula: (Al
2(OR
1O)
aA
bB
c)
X(OC(R
2)O)
Y(ZrA
dB
e)
Z wherein X, Y, and Z are at least 1, R
2 is an alkyl, alkenyl, aminoalkyl, carboxyalkyl, mercaptoalkyl, or epoxyalkyl group,
having from 2 to 17 carbon atoms, and the ratio of X:Z is from about 2:1 to about
5:1. Additional zirco-aluminate complexes are described in
U.S. Patent No. 4,650,526.
[0082] Examples of dyes that can be present in the at least partial coating according to
various embodiments disclosed herein include organic dyes that are capable of imparting
a desired color or other optical property to the at least partial coating.
[0083] As used herein, the term "alignment promoter" means an additive that can facilitate
at least one of the rate and uniformity of the alignment of a material to which it
is added. Examples of alignment promoters that can be present in the at least partial
coatings according to various embodiments disclosed herein include those described
in
U.S. Patent 6,338,808 and
U.S. Patent Publication No. 2002/0039627.
[0084] Examples of kinetic enhancing additives that can be present in the at least partial
coating according to various embodiments disclosed herein include epoxy-containing
compounds, organic polyols, and/or plasticizers. More specific examples of such kinetic
enhancing additives are disclosed in
U.S. Patent 6,433,043 and
U.S. Patent Publication No. 2003/0045612.
[0085] Examples of photoinitiators that can be present in the at least partial coating according
to various embodiments disclosed herein include cleavage-type photoinitiators and
abstraction-type photoinitiators. Examples of cleavage-type photoinitiators include
acetophenones, α-aminoalkylphenones, benzoin ethers, benzoyl oximes, acylphosphine
oxides and bisacylphosphine oxides or mixtures of such initiators. A commercial example
of such a photoinitiator is DAROCURE® 4265, which is available from Ciba Chemicals,
Inc. Examples of abstraction-type photoinitiators include benzophenone, Michler's
ketone, thioxanthone, anthraquinone, camphorquinone, fluorone, ketocoumarin or mixtures
of such initiators.
[0086] Another example of a photoinitiator that can be present in the LC compositions according
to various embodiments disclosed herein is a visible light photoinitiator. Examples
of suitable visible light photoinitiators are set forth at column 12, line 11 to column
13, line 21 of
U.S. Patent 6,602,603.
[0087] Examples of thermal initiators include organic peroxy compounds and azobis(organonitrile)
compounds. Specific examples of organic peroxy compounds that are useful as thermal
initiators include peroxymonocarbonate esters, such as tertiarybutylperoxy isopropyl
carbonate; peroxydicarbonate esters, such as di(2-ethylhexyl) peroxydicarbonate, di(secondary
butyl) peroxydicarbonate and diisopropylperoxydicarbonate; diacyperoxides, such as
2,4-dichlorobenzoyl peroxide, isobutyryl peroxide, decanoyl peroxide, lauroyl peroxide,
propionyl peroxide, acetyl peroxide, benzoyl peroxide and p-chlorobenzoyl peroxide;
peroxyesters such as t-butylperoxy pivalate, t-butylperoxy octylate and t-butylperoxyisobutyrate;
methylethylketone peroxide, and acetylcyclohexane sulfonyl peroxide. In one embodiment
the thermal initiators used are those that do not discolor the resulting polymerizate.
Examples of azobis(organonitrile) compounds that can be used as thermal initiators
include azobis(isobutyronitrile), azobis(2,4-dimethylvaleronitrile) or a mixture thereof.
[0088] Examples of polymerization inhibitors include: nitrobenzene, 1,3,5,-trinitrobenzene,
p-benzoquinone, chloranil, DPPH, FeCl
3, CuCl
2, oxygen, sulfur, aniline, phenol, p-dihydroxybenzene, 1,2,3-trihydroxybenzene, and
2,4,6-trimethylphenol.
[0089] Examples of solvents that can be present in the LC compositions according to various
embodiments disclosed herein include those that will dissolve solid components of
the LC compositions, that are compatible with the LC compositions and the elements
and substrates, and/or can ensure uniform coverage of a surface(s) to which the LC
composition is applied. Potential solvents include the following: propylene glycol
monomethyl ether acetate and their derivates (sold as DOWANOL
® industrial solvents), acetone, amyl propionate, anisole, benzene, butyl acetate,
cyclohexane, dialkyl ethers of ethylene glycol, e.g., diethylene glycol dimethyl ether
and their derivates (sold as CELLOSOLVE
® industrial solvents), diethylene glycol dibenzoate, dimethyl sulfoxide, dimethyl
formamide, dimethoxybenzene, ethyl acetate, isopropyl alcohol, methyl cyclohexanone,
cyclopentanone, methyl ethyl ketone, methyl isobutyl ketone, methyl propionate, propylene
carbonate, tetrahydrofuran, toluene, xylene, 2-methoxyethyl ether, 3-propylene glycol
methyl ether, and mixtures thereof.
[0090] In certain embodiments, the LC compositions of the present disclosure may further
comprise at least one additional polymeric material. Suitable examples of additional
polymeric materials that may be used in conjunction with various embodiments disclosed
herein include, for example, homopolymers and copolymers, prepared from the monomers
and mixtures of monomers disclosed in
U.S. Patent No. 5,962,617 and in
U.S. Patent No. 5,658,501 from column 15, line 28 to column 16, line 17. For example, such polymeric materials
can be thermoplastic or thermoset polymeric materials, can be transparent or optically
clear, and can have any refractive index required. Examples of such disclosed monomers
and polymers include: polyol(allyl carbonate) monomers, e.g., allyl diglycol carbonates
such as diethylene glycol bis(allyl carbonate), which monomer is sold under the trademark
CR-39 by PPG Industries, Inc.; polyurea-polyurethane (polyurea-urethane) polymers,
which are prepared, for example, by the reaction of a polyurethane prepolymer and
a diamine curing agent, a composition for one such polymer being sold under the trademark
TRIVEX by PPG Industries, Inc.; polyol(meth)acryloyl terminated carbonate monomer;
diethylene glycol dimethacrylate monomers; ethoxylated phenol methacrylate monomers;
diisopropenyl benzene monomers; ethoxylated trimethylol propane triacrylate monomers;
ethylene glycol bismethacrylate monomers; poly(ethylene glycol) bismethacrylate monomers;
urethane acrylate monomers; poly(ethoxylated bisphenol A dimethacrylate); poly(vinyl
acetate); poly(vinyl alcohol); poly(vinyl chloride); poly(vinylidene chloride); polyethylene;
polypropylene; polyurethanes; polythiourethanes; thermoplastic polycarbonates, such
as the carbonate-linked resin derived from bisphenol A and phosgene, one such material
being sold under the trademark LEXAN; polyesters, such as the material sold under
the trademark MYLAR; poly(ethylene terephthalate); polyvinyl butyral; poly(methyl
methacrylate), such as the material sold under the trademark PLEXIGLAS, and polymers
prepared by reacting polyfunctional isocyanates with polythiols or polyepisulfide
monomers, either homopolymerized or co-and/or terpolymerized with polythiols, polyisocyanates,
polyisothiocyanates and optionally ethylenically unsaturated monomers or halogenated
aromatic-containing vinyl monomers. Also contemplated are copolymers of such monomers
and blends of the described polymers and copolymers with other polymers, for example,
to form block copolymers or interpenetrating network products.
[0091] According to one specific embodiment, the additional polymeric material is chosen
from polyacrylates, polymethacrylates, poly(C
1 -C
12) alkyl methacrylates, polyoxy(alkylene methacrylates), poly (alkoxylated phenol methacrylates),
cellulose acetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate
butyrate, poly(vinyl acetate), poly(vinyl alcohol), poly(vinyl chloride), poly(vinylidene
chloride), poly(vinylpyrrolidone), poly((meth)acrylamide), poly(dimethyl acrylamide),
poly(hydroxyethyl methacrylate), poly((meth)acrylic acid), thermoplastic polycarbonates,
polyesters, polyurethanes, polythiourethanes, poly(ethylene terephthalate), polystyrene,
poly(alpha methylstyrene), copoly(styrene-methylmethacrylate), copoly(styrene-acrylonitrile),
polyvinylbutyral and polymers of members of the group consisting of polyol(allyl carbonate)monomers,
mono-functional acrylate monomers, mono-functional methacrylate monomers, polyfunctional
acrylate monomers, polyfunctional methacrylate monomers, diethylene glycol dimethacrylate
monomers, diisopropenyl benzene monomers, alkoxylated polyhydric alcohol monomers
and diallylidene pentaerythritol monomers.
[0092] According to another specific embodiment, the at least one additional polymeric material
may be a homopolymer or copolymer of monomer(s) chosen from acrylates, methacrylates,
methyl methacrylate, ethylene glycol bis methacrylate, ethoxylated bisphenol A dimethacrylate,
vinyl acetate, vinylbutyral, urethane, thiourethane, diethylene glycol bis(allyl carbonate),
diethylene glycol dimethacrylate, diisopropenyl benzene, and ethoxylated trimethylol
propane triacrylate.
[0093] Still other embodiments of the present disclosure provide for optical elements. The
optical elements comprise a substrate and an at least partial layer of the LC compositions
according to the various embodiments described herein on at least a portion of the
substrate. As used herein the term "optical" means pertaining to or associated with
light and/or vision. For example according to various embodiments, the optical element
or device can be chosen from ophthalmic elements and devices, display elements and
devices, windows, mirrors, and active and passive liquid crystal cell elements and
devices.
[0094] As used herein, the term "liquid crystal cell" refers to a structure containing a
liquid crystal material that is capable of being ordered. Active liquid crystal cells
are cells wherein the liquid crystal material is capable of being switched between
ordered and disordered states or between two ordered states by the application of
an external force, such as electric or magnetic fields. Passive liquid crystal cells
are cells wherein the liquid crystal material maintains an ordered state. One example
of an active liquid crystal cell element or device is a liquid crystal display.
[0095] As used herein the term "ophthalmic" means pertaining to or associated with the eye
and vision. Examples of ophthalmic elements include corrective and non-corrective
lenses, including single vision or multi-vision lenses, which may be either segmented
or non-segmented multi-vision lenses (such as bifocal lenses, trifocal lenses and
progressive lenses), as well as other elements used to correct, protect, or enhance
(cosmetically or otherwise) vision, including contact lenses, intra-ocular lenses,
magnifying lenses, and protective lenses or visors; and may also include partially
formed lenses and lens blanks. As used herein the term "display" means the visible
or machine-readable representation of information in words, numbers, symbols, designs
or drawings. Examples of display elements and devices include screens, monitors, and
security elements security marks and authentication marks. As used herein the term
"window" means an aperture adapted to permit the transmission of radiation therethrough.
Examples of windows include automotive and aircraft transparencies, filters, shutters,
and optical switches. As used herein the term "mirror" means a surface that specularly
reflects a large fraction of incident light.
[0096] While dichroic compounds are capable of preferentially absorbing one of two orthogonal
components of plane polarized light, it is generally necessary to suitably position
or arrange the molecules of a dichroic compound in order to achieve a net linear polarization
effect. Similarly, it is generally necessary to suitably position or arrange the molecules
of a dichroic or photochromic-dichroic compound to achieve a net linear polarization
effect. That is, it is generally necessary to align the molecules of the dichroic
or photochromic-dichroic compound such that the long axes of the molecules of the
dichroic or photochromic-dichroic compound in an activated state are generally parallel
to each other. Therefore, according to various embodiments disclosed herein, the at
least one dichroic or photochromic-dichroic compound is at least partially aligned.
Further, if the activated state of the dichroic or photochromic-dichroic compound
corresponds to a dichroic state of the material, the at least one dichroic or photochromic-dichroic
compound can be at least partially aligned such that the long axis of the molecules
of the dichroic or photochromic-dichroic compound in the activated state are aligned.
As used herein the term "align" means to bring into suitable arrangement or position
by interaction with another material, compound or structure.
[0097] In certain embodiments, the dichroic compound and/or the photochromic-dichroic compound
or other anisotropic material (such as certain embodiments of the mesogen containing
compounds described herein) may be at least partially aligned. At least partial alignment
of compositions, such as those comprising a dichroic compound, a photochromic-dichroic
compound or other anisotropic material, may be effected by at least one of exposing
the at least a portion of the composition to a magnetic field, exposing the at least
a portion of the composition to a shear force, exposing the at least a portion of
the composition to an electric field, exposing the at least a portion of the composition
to plane-polarized ultraviolet radiation, exposing the at least a portion of the composition
to infrared radiation, drying the at least a portion of the composition, etching the
at least a portion of the composition, rubbing the at least a portion of the composition,
and aligning the at least a portion of the composition with another structure or material,
such as an at least partially ordered alignment medium. It is also possible to align
the dichroic compound and/or the photochromic-dichroic compound or other anisotropic
material (such as certain embodiments of the mesogen containing compounds described
herein) with an oriented surface. That is, liquid crystal molecules can be applied
to a surface that has been oriented, for example by rubbing, grooving, or photo-alignment
methods, and subsequently aligned such that the long axis of each of the liquid crystal
molecules takes on an orientation that is generally parallel to the general direction
of orientation of the surface. Examples of liquid crystal materials suitable for use
as alignment media according to various embodiments disclosed herein include the mesogen
containing compounds or residues thereof, liquid crystal polymers, liquid crystal
pre-polymers, liquid crystal monomers, and liquid crystal mesogens. As used herein
the term "pre-polymer" means partially polymerized materials.
[0098] For example, according to embodiments where the optical element comprises a cured
layer which comprises a photochromic compound, or a photochromic-dichroic compound,
the coating may be adapted to switch from a first state to a second state in response
to at least actinic radiation and further be able to revert back to the first state
in response to thermal energy. In other embodiments, the coating may be adapted to
linearly polarize at least transmitted radiation in at least one of the first state
and the second state. In certain embodiments, the coating may linearly polarize at
least transmitted radiation in both the first state and the second state.
[0099] As discussed above, one embodiment provides, in part, an optical element comprising
an at least partial layer or coating having a first state and a second state connected
to at least a portion of at least one surface of a substrate. As used herein the term
"coating" means a supported film derived from a flowable composition, which may or
may not have a uniform thickness, and specifically excludes polymeric sheets. The
layer or coating may be cured after application to the surface of the optical element
to form a cured layer or coating. As used herein the term "sheet" means a pre-formed
film having a generally uniform thickness and capable of self-support. Further, as
used herein the term "connected to" means in direct contact with an object or indirect
contact with an object through one or more other structures or materials, at least
one of which is in direct contact with the object. Thus, according to various embodiments
disclosed herein, the at least partial coating can be in direct contact with at least
a portion of the substrate or it can be in indirect contact with at least a portion
of the substrate through one or more other structures or materials. For example the
at least partial coating can be in contact with one or more other at least partial
coatings, polymer sheets or combinations thereof, at least one of which is in direct
contact with at least a portion of the substrate.
[0100] According to certain embodiments, the at least partial layer may be at least partially
aligned. Suitable methods for at least partially aligning the at least partial layer
include at least one of exposing the at least a portion of the composition to a magnetic
field, exposing the at least a portion of the composition to a shear force, exposing
the at least a portion of the composition to an electric field, exposing the at least
a portion of the composition to plane-polarized ultraviolet radiation, exposing the
at least a portion of the composition to infrared radiation, drying the at least a
portion of the composition, etching the at least a portion of the composition, rubbing
the at least a portion of the composition, and aligning the at least a portion of
the composition with another structure or material, such as an at least partially
ordered alignment medium. Suitable alignment methods for layers are described in greater
detail in
U.S. Patent No. 7,097,303, at column 27, line 17 to column 28, line 45.
[0101] According to certain embodiments of the optical elements described herein, the at
least partial layer may be adapted to switch from a first state to a second state
in response to at least actinic radiation and to revert back to the first state in
response to thermal energy. For example, the at least partial layer comprising a photochromic
compound or a photochromic-dichroic compound, may be adapted to switch from a first
non-colored or clear state to a second colored state in response to at least actinic
radiation and to revert back to the first clear state in response to thermal energy.
In other embodiments where the at least partial layer may be adapted to linearly polarize
at least transmitted radiation in at least one of the first state and the second state.
For example, the at least partial layer may transmit linearly polarized radiation
in certain embodiments which comprise a dichroic compound or photochromic-dichroic
compound.
[0102] According to specific embodiments of the optical elements of the present disclosure,
the at least partial layer may comprise a polymer or copolymer comprising the residue
of one or more mesogen containing compounds described herein. The at least partial
layer comprising a polymer or copolymer comprising the residue of a mesogen containing
compound may be a cured at least partial layer. In other embodiments, the at least
partial layer may comprise a liquid crystal phase. The liquid crystal phase may be
a nematic phase, a smectic phase, a chiral nematic phase, or a discotic phase.
[0103] As used herein to modify the term "state," the terms "first" and "second" are not
intended to refer to any particular order or chronology, but instead refer to two
different conditions or properties. For example the first state and the second state
of the coating may differ with respect to at least one optical property, such as the
absorption or linearly polarization of visible and/or UV radiation. According to certain
embodiments of the ophthalmic elements described herein, the at least partial layer
may be adapted to switch from a first state to a second state in response to at least
actinic radiation and to revert back to the first state in response to thermal energy.
For example, in those embodiments where the at least partial layer comprises a-photochromic
compound or a photochromic-dichroic compound, the at least partial layer may be adapted
to switch from a first non-colored or clear state to a second colored state in response
to at least actinic radiation and to revert back to the first clear state in response
to thermal energy. Alternatively, the at least partial coating can be adapted to have
a first color in the first state and a second color in the second state. In other
embodiments where the at least partial layer may be adapted to linearly polarize at
least transmitted radiation in at least one of the first state and the second state.
For example, the at least partial layer may transmit linearly polarized radiation
in certain embodiments which comprise a dichroic compound or photochromic-dichroic
compound. In other embodiments, the at least partial layer may comprise a liquid crystal
phase. The liquid crystal phase may be a nematic phase, a smectic phase, a chiral
nematic phase, or a discotic phase. According to still other embodiments, the at least
partial coating having a first state and a second state can be adapted to have a first
absorption spectrum in the first state, a second absorption spectrum in the second
state, and to be linearly polarizing in both the first and second states.
[0104] Still other embodiments of the present disclosure provide for a liquid crystal cell.
According to these embodiments, the liquid crystal cell may comprising a first substrate
having a first surface; a second substrate having a second surface; and a liquid crystal
composition as described herein. Referring still to the liquid crystal cell, the second
surface of the second substrate may be opposite and spaced apart from the first surface
of the first substrate so as to define a region. The liquid crystal composition may
be placed in the region between the first substrate and second substrate. Alternatively,
the liquid crystal composition may be incorporated into an at least partial layer
on at least one of the first surface of the first substrate, the second surface of
the second substrate, or both the first and second surfaces. The liquid crystal cell
may be utilized as, for example display elements, including screens, monitors, or
security elements.
[0105] in other embodiments, the liquid crystal cells may further comprise an at least partial
layer connected to at least a portion of a surface of at least one of the first substrate
and the second substrate, such as the first surface and/or second surface. The at
least partial layer may be a linearly polarizing layer, a circularly polarizing layer,
an elliptically polarizing layer, a photochromic layer, a reflective layer, a tinted
layer, a retarder layer, and a wide-angle view layer.
[0106] According to certain embodiments, the liquid crystal cell may be a pixelated cell.
As used herein, the term "pixelated" means that an article, such as a display element
or liquid crystal cell may be broken down into a plurality of individual pixels (i.e.,
single point occupying a specific location within a display, image or cell. In certain
embodiments, the liquid crystal cell may be a pixilated cell comprising a plurality
of regions or compartments (i.e., pixels). The characteristics of the individual pixels,
such as color, polarization and the like, may be controlled relative to the other
pixels in the display element, liquid crystal, or article.
[0107] According to still other embodiments, the present disclosure provides for articles
of manufacture comprising a liquid crystal composition as described herein. Specific
articles of manufacture include molded articles, assembled articles and cast articles.
[0108] Additionally, the present disclosure also provides methods for forming liquid crystal
compositions, optical elements, ophthalmic elements, liquid crystal cells and articles
of manufacture, such as those described herein.
[0109] For example, according to one embodiment, the present disclosure provides methods
for forming an optical element, including an ophthalmic element. The methods comprise
the step of formulating a liquid crystal composition; coating at least a portion of
a substrate with the liquid crystal composition; at least partially aligning at least
a portion of the liquid crystal composition in the coating layer; and curing the liquid
crystal coating layer.
[0110] Methods of at least partially aligning the at least a portion of the liquid crystal
composition in the coating are described herein and in
U.S. Patent No. 7,097,303, at column 27, line 17 to column 28, line 45.
[0111] Curing the liquid crystal coating layer may include at least partially polymerizing
the liquid crystal composition. Methods for at least partially polymerizing a liquid
crystal composition include exposing at least a portion of the liquid crystal composition
to at least one of thermal energy (for example to activate a thermal initiator); infrared
radiation, ultraviolet radiation, visible radiation, gamma radiation, microwave radiation,
electron radiation or combinations thereof so as to initiate the polymerization reaction
of the polymerizable components or cross-linking with or without a catalyst or initiator.
If desired or required, this can be followed by a heating step. According to certain
embodiments, the liquid crystal coating layer may be cured to a specific hardness.
For example, in certain embodiments, the liquid crystal coating layer may be cured
to have a Fischer microhardness ranging from 0 to 150 Newtons/mm
2 that also exhibits good photochromic and/or dichroic response characteristics. In
another embodiment, the liquid crystal composition may be cured to a Fischer microhardness
less than 60 Newtons/mm
2, e.g. from 0 to 59.9 Newtons/mm
2, or alternatively from 5 to 25 N/mm
2. In still other embodiments, the liquid crystal coating layer may be cured to have
a Fischer microhardness ranging from 150 N/mm
2 to 250 N/mm
2 or alternatively from 150 N/mm
2 to 200 N/mm
2.
[0112] According to specific embodiments, the at least one additive may be adapted to affect
a property of the liquid crystal composition, such as adjusting the liquid crystal
clear temperature of the liquid crystal composition, lowering a viscosity of the liquid
crystal composition, widening a phase temperature for a nematic phase of the liquid
crystal composition, stabilizing a phase of the liquid crystal composition or controlling
the tilt of the liquid crystal composition.
[0113] Specific methods for forming optical elements, such as ophthalmic elements which
comprise at least a partial layer comprising a liquid crystal composition as described
herein, on at least a portion of a surface of a substrate, are described in detail
in
U.S. Patent No. 7,342,112 at column 83, line 16 of column 84, line 10. These disclosed methods include imbibing,
coating, overmolding, spin coating, spray coating, spray and spin coating, curtain
coating, flow coating, dip coating, injection molding, casting, roll coating, and
wire coating.
[0114] Generally speaking, substrates that are suitable for use in conjunction with various
embodiments disclosed herein include substrates formed from organic materials, inorganic
materials, or combinations thereof (for example, composite materials). Specific examples
of organic materials that may be used to form the substrates disclosed herein include
polymeric materials, such as those discussed in detail above.
[0115] Other examples of organic materials suitable for use in forming the substrates according
to various embodiments disclosed herein include both synthetic and natural organic
materials, including: opaque or translucent polymeric materials, natural and synthetic
textiles, and cellulosic materials such as, paper and wood.
[0116] Examples of inorganic materials suitable for use in forming the substrates according
to various embodiments disclosed herein include glasses, minerals, ceramics, and metals.
For example, in one embodiment the substrate can comprise glass. In other embodiments,
the substrate can have a reflective surface, for example, a polished ceramic substrate,
metal substrate, or mineral substrate. In other embodiments, a reflective coating
or layer can be deposited or otherwise applied to a surface of an inorganic or an
organic substrate to make it reflective or to enhance its reflectivity.
[0117] Further, according to certain embodiments disclosed herein, the substrates may have
a protective coating, such as an abrasion-resistant coating, such as a "hard coat,"
on their exterior surfaces. For example, commercially available thermoplastic polycarbonate
ophthalmic lens substrates are often sold with an abrasion-resistant coating already
applied to its exterior surfaces because these surfaces tend to be readily scratched,
abraded or scuffed. An example of such a lens substrate is the GENTEX™ polycarbonate
lens (available from Gentex Optics). Therefore, as used herein the term "substrate"
includes a substrate having a protective coating, such as an abrasion-resistant coating,
on its surface(s).
[0118] Still further, the substrates according to various embodiments disclosed herein can
be untinted, tinted, linearly polarizing, circularly polarizing, elliptically polarizing,
photochromic, or tinted-photochromic substrates. As used herein with reference to
substrates the term "untinted" means substrates that are essentially free of coloring
agent additions (such asconventional dyes) and have an absorption spectrum for visible
radiation that does not vary significantly in response to actinic radiation. Further,
with reference to substrates the term "tinted" means substrates that have a coloring
agent addition (such as dyes) and an absorption spectrum for visible radiation that
does not vary significantly in response to actinic radiation.
[0119] As used herein, the term "linearly polarizing" with reference to substrates refers
to substrates that are adapted to linearly polarize radiation (i.e., confine the vibrations
of the electric vector of light waves to one direction). As used herein, the term
"circularly polarizing" with reference to substrates refers to substrates that are
adapted to circularly polarize radiation. As used herein, the term "elliptically polarizing"
with reference to substrates refers to substrates that are adapted to elliptically
polarize radiation. Further, as used herein, with reference to substrates, the term
"tinted-photochromic" means substrates containing a coloring agent addition as well
as a photochromic material, and having an absorption spectrum for visible radiation
that varies in response to at least actinic radiation. Thus, for example the tinted-photochromic
substrate can have a first color characteristic of the coloring agent and a second
color characteristic of the combination of the coloring agent the photochromic material
when exposed to actinic radiation.
[0120] As described herein, in certain embodiments the optical element may be a security
element. Examples of security elements include security marks and authentication marks
that are connected to at least a portion of a substrate, such as: access cards and
passes, e.g., tickets, badges, identification or membership cards, debit cards etc.;
negotiable instruments and non-negotiable instruments e.g., drafts, checks, bonds,
notes, certificates of deposit, stock certificates, etc.; government documents, e.g.,
currency, licenses, identification cards, benefit cards, visas, passports, official
certificates, deeds etc.; consumer goods, e.g., software, compact discs ("CDs"), digital-video
discs ("DVDs"), appliances, consumer electronics, sporting goods, cars, etc.; credit
cards; and merchandise tags, labels and packaging.
[0121] The security element can be connected to at least a portion of a substrate chosen
from a transparent substrate and a reflective substrate. Alternatively, according
to certain embodiments wherein a reflective substrate is required, if the substrate
is not reflective or sufficiently reflective for the intended application, a reflective
material can be first applied to at least a portion of the substrate before the security
mark is applied thereto. For example, a reflective aluminum coating can be applied
to the at least a portion of the substrate prior to forming the security element thereon.
Still further, security element can be connected to at least a portion of a substrate
chosen from untinted substrates, tinted substrates, photochromic substrates, tinted-photochromic
substrates, linearly polarizing, circularly polarizing substrates, and elliptically
polarizing substrates.
[0122] Furthermore, security element according to the aforementioned embodiment can further
comprise one or more other coatings or sheets to form a multi-layer reflective security
element with viewing angle dependent characteristics as described in
U.S. Patent 6,641,874.
[0123] The optical elements according to various embodiments disclosed herein can further
comprise at least one additional at least partial coating that can facilitate bonding,
adhering, or wetting of any of the various coatings connected to the substrate of
the optical element. For example the optical element can comprise an at least partial
primer coating between the at least partial coating having the first state and the
second state and a portion of the substrate. Further, the primer coating can serve
as a barrier coating to prevent interaction of the coating ingredients with the element
or substrate surface and vice versa.
[0124] Examples of primer coatings that can be used in conjunction with various embodiments
disclosed herein include coatings comprising coupling agents, at least partial hydrolysates
of coupling agents, and mixtures thereof. As used herein "coupling agent" means a
material having at least one group capable of reacting, binding and/or associating
with a group on at least one surface. In one embodiment, a coupling agent can serve
as a molecular bridge at the interface of at least two surfaces that can be similar
or dissimilar surfaces. Coupling agents, in another embodiment, can be monomers, oligomers,
pre-polymers and/or polymers. Such materials include organo-metallics such as silanes,
titanates, zirconates, aluminates, zirconium aluminates, hydrolysates thereof and
mixtures thereof. As used herein the phrase "at least partial hydrolysates of coupling
agents" means that at least some to all of the hydrolyzable groups on the coupling
agent are hydrolyzed. In addition to coupling agents and/or hydrolysates of coupling
agents, the primer coatings can comprise other adhesion enhancing ingredients. For
example the primer coating can further comprise an adhesion-enhancing amount of an
epoxy-containing material. Adhesion-enhancing amounts of an epoxy-containing material
when added to the coupling agent containing coating composition can improve the adhesion
of a subsequently applied coating as compared to a coupling agent containing coating
composition that is essentially free of the epoxy-containing material. Other examples
of primer coatings that are suitable for use in conjunction with the various embodiments
disclosed herein include those described
U.S. Patent 6,602,603 and
U.S. Patent 6,150,430.
[0125] The optical elements according to various embodiments disclosed herein can further
comprise at least one additional at least partial coating chosen from conventional
photochromic coatings, anti-reflective coatings, linearly polarizing coatings, circularly
polarizing coatings, elliptically polarizing coatings, transitional coatings, primer
coatings (such as those discussed above), and protective coatings connected to at
least a portion of the substrate. For example the at least one additional at least
partial coating can be over at least a portion of the at least partial coating having
the first state and the second state, i.e., as an overcoating; or under at least a
portion of the at least partial coating, i.e., as an undercoating. Additionally or
alternatively, the at least partial coating having the first state and the second
state can be connected at least a portion of a first surface of the substrate and
the at least one additional at least partial coating can be connected to at least
a portion of a second surface of the substrate, wherein the first surface is opposite
the second surface.
[0126] Examples of conventional photochromic coatings include coatings comprising any of
the conventional photochromic compounds that are discussed in detail below. For example
the photochromic coatings can be photochromic polyurethane coatings, such as those
described in
U.S. Patent 6,187,444; photochromic aminoplast resin coatings, such as those described in
U.S. Patents 4,756,973,
6,432,544 and
6,506,488; photochromic polysilane coatings, such as those described in
U.S. Patent 4,556,605; photochromic poly(meth)acrylate coatings, such as those described in
U.S. Patents 6,602,603,
6,150,430 and
6,025,026, and WIPO Publication
WO 01/02449; polyanhydride photochromic coatings, such as those described in
U.S. Patent 6,436,525; photochromic polyacrylamide coatings such as those described in
U.S. Patent 6,060,001; photochromic epoxy resin coatings, such as those described in
U.S. Patents 4,756,973 and
6,268,055; and photochromic poly(urea-urethane) coatings, such as those described in
U.S. Patent 6,531,076.
[0127] Examples of linearly polarizing coatings include coatings comprising conventional
dichroic compounds such as those discussed above.
[0128] As used herein the term "transitional coating" means a coating that aids in creating
a gradient in properties between two coatings. For example a transitional coating
can aid in creating a gradient in hardness between a relatively hard coating and a
relatively soft coating. Examples of transitional coatings include radiation-cured
acrylate-based thin films.
[0129] Examples of protective coatings include abrasion-resistant coatings comprising organo
silanes, abrasion-resistant coatings comprising radiation-cured acrylate-based thin
films, abrasion-resistant coatings based on inorganic materials such as silica, titania
and/or zirconia, organic abrasion-resistant coatings of the type that are ultraviolet
light curable, oxygen barrier-coatings, UV-shielding coatings, and combinations thereof.
For example the protective coating can comprise a first coating of a radiation-cured
acrylate-based thin film and a second coating comprising an organo-silane. Examples
of commercial protective coatings products include SILVUE
®124 and HI-GARD® coatings, available from SDC Coatings, Inc. and PPG Industries, Inc.,
respectively.
[0130] According to specific embodiments, the present disclosure provides for mesogen containing
compounds having the following structures as disclosed in Table 1.
Table 1: Structure of Specific Mesogen Containing Compounds
| Structure and name |

|
| 1,12-bis{2-(4-(4-(4-(3-(methacryloyloxy)propyloxy)benzoyloxy)phenyl)benzoyloxy)ethyloxy)
dodecyl-1,12-dione |

|
| 1,12-bis(6-(4-(4-(4-(6-(methacryloyloxy)hexyloxy)benzoyloxy)phenyl)benzoyloxy)hexyloxy)
dodecyl-1,12-dione |

|
| 1,10-bis(6-(4-(4-(4-(6-(methacryloyloxy)hexyloxy)benzoyloxy)phenyl)benzoyloxy)hexyloxy)
2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-hexadecafluorodecyl-1,10-dione |

|
| 1,12-bis{6-(4-(4-(6-methacryloyloxyhexyloxy)benzoyloxy)benzoyloxy)hexyloxy)dodecyl-1,12-dione |

|
| 1-{3-(4-(3-(4-(6-(4(4-(4-(6-methacryloyloxyhexyloxy)benzoyloxy)phenyl)benzoyloxy)hexyloxy)-4-oxobutoyloxy)propyloxy)benzoyloxy)propyloxy}-4-{(6-(4(4-(4-(6-methacryloyloxyhexyloxy)
benzoyloxy)phenyl)benzoyloxy)hexyloxy)}butane-1,4-dione |

|
| 1,4-bis{(6-(6-(6-(6-(6-(6-(trans-4-(4-(6-acryloyloxyhexyloxy)benzoyloxy)phenyl)cyclohexyloxy)
hexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy}
butan-1,4-dione |

|
| 1,4-bis{(6-(6-(6-(6-(6-(4-(4-(4-(4-(6-acryloyloxyhexyloxy)benzoyloxy)phenyl) phenyloxycarbonyl)phenyloxy)hexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy}butan-1,4-dione |
Examples
[0131] Liquid Crystal Monomers (LCM) 1-2 describe the preparation of the liquid crystal
monomers used in the Examples. Photochromic Compounds (PC) 1-4 describe the preparation
of the photochromic compounds used in the Examples. Dichroic Dyes (DD) 1 and 2 describe
the dichroic dyes used in the Examples. Examples 1-5 describe the formulations containing
the LCM prepared according to the method described with Table 2. Comparative Examples
1-7 was prepared using commercially available liquid crystal monomers according to
the method described with Table 4. Example 6 describes the preparation and testing
of the samples coated with Examples 1-5 and Comparative Examples 1-7.
The following abbreviations were used for the chemicals listed:
Al(OiPr)3 - aluminum triisopropylate
DHP - 3,4-dihydro-2H-pyran
DCC - dicyclohexylcarbodiimide
DIAD - diisopropyl azodicarboxylate
DMAP - 4-dimethylaminopyridine
PPh3 - triphenyl phosphine
PPTS - pyridine p-toluenesulfonate
pTSA - p-toluenesulfonic acid
NMP - N-methyl pyrrolidone
BHT - butylated hydroxytoluene
TBD - 1,5,7-triazabicyclo[4.4.0]dec-5-ene
THF - tetrahyrdofuran
DMF - dimethyl formamide
DMA - dimethyl aniline
Example 1 -LCM-1 (not an example of the present invention)
Step 1
[0132] To a reaction flask was added 4-hydroxybenzoic acid (90 grams (g), 0.65 mole (mol)),
ethyl ether (1000 milliliters (mL)) and
p-toluenesulfonic acid (pTSA) (2 g). The resulting suspension was stirred at room temperature.
3,4-Dihydro-2H-pyran (DHP) (66 g, 0.8 mol) was added to the mixture. The suspension
turned clear soon after the addition of DHP and a white crystalline precipitate formed.
The mixture was then stirred at room temperature overnight. The resulting precipitates
were collected by vacuum filtration and washed with ethyl ether. White crystals were
recovered as the product (90 g, 62% yield). Nuclear Magnetic Resonance (NMR) showed
that the product had a structure consistent with 4-(tetrahydro-2H-pyran-2-yloxy)benzoic
acid.
Step 2
[0133] To a reaction flask was added 4-(tetrahydro-2H-pyran-2-yloxy)benzoic acid (65.5 g,
0.295 mol) from Step 1, 4-(trans-4-pentylcyclohexyl)phenol (70.3 g, 0.268 mol), dicyclohexylcarbodiimide
(DCC) (66.8 g, 0.324 mol), 4-dimethylaminopyridine (DMAP) (3.3 g) and methylene chloride
(1 L). The resulting mixture was mechanically stirred at 0°C for 30 minutes, then
at room temperature for 2 hours. The resulting solids were filtered off. The solution
was concentrated until white crystals started to precipitate. One liter of methanol
was added into the mixture with stirring. The precipitated solid crystalline product
was collected by vacuum filtration and washed with methanol. White crystals (126 g)
were recovered as the product. NMR showed that the product had a structure consistent
with 4-(trans-4-pentylcyclohexyl)phenyl 4-(tetrahydro-2H-pyran-2-yloxy)benzoate.
Step 3
[0134] The product from Step 2,4-(trans-4-pentylcyclohexyl)phenyl 4-(tetrahydro-2H-pyran-2-yloxy)benzoate
(120 g, 0.26 mol), was dissolved in 1,2-dichloroethane (600 mL) in an appropriate
reaction flask. Methanol (300 mL) and pyridine p-toluenesulfonate (PPTS) (9 g, 36
millimole (mmol)) was added. The mixture was heated to reflux and maintained at reflux
for 6 hours. Upon standing at room temperature overnight, white crystals precipitated
out which were collected by vacuum filtration. The mother liquid was concentrated
and more white crystals precipitated out with the addition of methanol. The combined
product (90 g) was washed with methanol (about 300 mL) three times and air dried.
NMR showed that the product had a structure consistent with 4-(trans-4-pentylcyclohexyl)phenyl
4-hydroxybenzoate.
Step 4
[0135] To a reaction flask was added the product of Step 3,4-(trans-4-pentylcyclohexyl)phenyl
4-hydroxybenzoate (70 g, 190 mmol), 6-chloro-1-hexanol (30 g, 220 mmol), N-methyl
pyrrolidone (NMP) (300 mL), Nal (6 g), and potassium carbonate (57 g, 410 mmol). The
resulting mixture was vigorously stirred at 85-90°C for 4 hours. The resulting mixture
was extracted using 1/1 volume ratio of ethyl acetate/hexanes (1L) and water (500
mL). The separated organic layer was washed several times with water to remove NMP
and then dried over anhydrous magnesium sulfate. After concentration, acetonitrile
was added to precipitate the product. White crystal (76 g) were collected by vacuum
filtration. NMR showed that the product had a structure consistent with 4-(trans-4-pentylcyclohexyl)phenyl
4-(6-hydroxyhexyloxy)benzoate.
Step 5
[0136] To a reaction flask was added the product of Step 4, 4-(trans-4-pentylcyclohexyl)
phenyl 4-(6-hydroxyhexyloxy)benzoate (2 g, 4.3 mmol), epsilon-caprolactone (2.94 g,
26 mmol), aluminum triisopropoxide (Al(OiPr)
3) (0.26 g, 1.3 mmol) and methylene chloride (40 mL). The resulting mixture was stirred
at room temperature for 8 hours. Butylated hydroxytoluene (BHT) (9 milligram (mg),
0.04 mmol), DMAP (0.05 g, 0.43 mmol) and N,N-diethylaniline (1.8 g, 15 mmol) was added
to the mixture and the mixture was stirred for half an hour. Freshly distilled methacryloyl
chloride (1.34 g, 13 mmol) was then added to the mixture. After stirring at room temperature
for 8 hours, the mixture was washed with 5 weight percent NaOH aqueous solution three
times, with an aqueous 1 Normal (N) HCl solution three times and then with the 5 weight
percent NaOH aqueous solution one more time. Note that whenever weight percent is
reported herein, it is based on the total weight of the solution. The organic layer
was separated and dried over anhydrous MgSO
4. After concentration, a methanol washing was done by adding 100 mL of methanol to
the recovered oil with stirring. After 10 minutes, the resulting cloudy mixture was
left at room temperature. After the cloudiness of the mixture cleared, methanol on
top of the mixture was decanted. This methanol wash was done three times. The recovered
oil was re-dissolved in ethyl acetate, dried over anhydrous magnesium sulfate and
concentrated. A viscous liquid (3.9 g) was recovered as the product. NMR showed that
the product had a structure consistent with 1-(6-(6-(6-(6-(6-(6-(6-(4-(4-(4-pentylcyclohexyl)
phenoxycarbonyl)phenoxy)hexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-2-methylprop-2-en-1-one
with n having an average distribution of 6.5 as represented by the following graphic
formula.

Example 2 - LCM-2
Step 1
[0137] The procedure of Step 2 of Example 1 was followed except that 4-(8-acryloxyoctoxy)benzoic
acid and 4-(4-trans-(6-hydroxyhexyloxy)cyclohexyl)phenol were used in place of 4-(tetrahydro-2H-pyran-2-yloxy)benzoic
acid and 4-(trans-4-pentylcyclohexyl) phenol. The product was further purified by
column separation. NMR showed that the product had a structure consistent with 4-(4-trans-(6-hydroxyhexyloxy)cyclohexyl)phenyl
4-(6-(acryloyloxy)hexyloxy)benzoate.
Step 2
[0138] The procedure of Step 5 of Example 1 was followed except that the product from Step
1 above, 4-(4-trans-(6-hydroxyhexyloxy)cyclohexyl)phenyl 4-(6-(acryloyloxy)hexyloxy)
benzoate, four equivalents of epsilon-caprolactone and 0.5 equivalents of succinyl
dichloride were used in place of 4-(trans-4-pentylcyclohexyl)phenyl 4-(6-hydroxyhexyloxy)benzoate,
six equivalents of epsilon-caprolactone and methacryloyl chloride. NMR showed that
the product had a structure consistent with 1,4-bis-{(6-(6-(6-(6-(6-(6-(4-(4-(6-acryloyloxyhexyloxy)
benzoyloxy)phenyl)cyclohexyloxy)hexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy)-6-oxohexyloxy}butan-1,4-dione
with m+n having an average distribution of 9.7 as represented by the following graphic
formula.

Photochromic Compounds (PC)
[0139] PC 1 and 2 were prepared following the procedures of
U.S. Patent Nos. 5,645,767 and
6,296,785 B1. NMR analysis showed the products to have structures consistent with the following
names.
| PC-1 - |
3,3-di(4-methoxyphenyl)-13,13-dimethyl-3H,13H-indeno[2',3':3,4]naphtho[1,2-b]pyran. |
| PC-2 - |
3-(4-methoxyphenyl)-3-(4-morpholinophenyl)-13,13-dimethyl-3H,13H-indeno[2',3':3,4]naphtho[1,2-b]pyran. |
Example PC-3
Step 1
[0140] Trimethyl orthoformate (32.6 mL, 297.5 mmol) and PPTS (3.0 g, 11.9 mmol) were added
to a suspension of 7-ethyl-2,3-dimethoxy-7H-benzo[c]fluorene-5,7-diol (20.0 g, 59.5
mmol) which diol was prepared according to the procedure of Step 1 of Example 3 described
in paragraph [0448] of
U.S. Patent Application Publication No. 2008/0051575, in methanol and heated to reflux for 2-3 hours (h). Upon completion of the reaction,
as indicated by thin layer chromatography (TLC), the mixture was cooled to room temperature
to afford precipitates. The resulting precipitates were collected by vacuum filtration
and washed with a minimum amount of cold methanol. Cream colored amorphous solid was
recovered as the product (20.0 g, 95% yield). NMR showed that the product had a structure
consistent with 7-ethyl-2,3,7-trimethoxy-7H-benzo[c]fluorene-5-ol.
Step 2
[0141] Methyl magnesium bromide (474.2 mL, 664.0 mmol) in toluene (355 mL) and THF (355
mL) were added to a 2 L round bottom flask. The flask was purged with nitrogen and
2,6-dimethyl piperidine (55.0 mL, 398.4 mmol) was added dropwise to the solution.
7-Ethyl-2,3,7-trimethoxy-7H-benzo[c]fluorene-5-ol (46.5 g, 132.8 mmol) from Step 1,
was added in several portions with vigorous stirring and the reaction mixture was
heated to reflux for 5 h. Upon completion of the reaction, as indicated by TLC, the
mixture was carefully poured into an aqueous solution of 10 weight percent, based
on the total weight of the solution, HCl (500 mL) at 0°C and the pH was carefully
adjusted to 4 by the addition of concentrated HCl. The organic-aqueous mixture was
stirred for 10-15 min, ethyl acetate was added three times using 500 mL each time
and the resulting phases were separated. The combined organic extract was dried with
sodium sulfate and concentrated under a vacuum to produce an oily residue. Dichloromethane
was added to the residue and stirred to produce precipitates. The precipitates (43.5
g, 97%) were collected by vacuum filtration and washed with a minimum amount of cold
dichloromethane. NMR showed that the product had a structure consistent with 7-ethyl-3,4-dimethoxy-7H-benzo[c]fluorene-2,5-diol.
Step 3
[0142] To a reaction flask was added 7-ethyl-3,4-dimethoxy-7H-benzo[c]fluorene-2,5-diol
(43.3 g, 128.7 mmol) from Step 2, 1,1-bis(4-methoxyphenyl)-prop-2-yn-1-ol (41.4 g,
154.5 mmol), dichloromethane (300 mL), triisopropylorthoformate (30 mL, 154.5 mmol)
and PPTS (3.2 g, 12.9 mmol). The resulting suspension was heated to reflux for 18
h. Upon completion of the reaction as indicated by TLC, the reaction mixture was passed
through a silica plug (500 g) and the product was eluted with chloroform. Fractions
containing the product were combined and concentrated under vacuum to produce an oily
residue. The oily residue (83.9 g) was used directly in the next step.
Step 4
[0143] To the reaction flask containing the oily residue (83.9 g, 143.2 mmol) from Step
3 was added dichloromethane (200 mL), 4'-(tetrahydro-2H-pyran-2-yloxy)biphenyl-4-carboxylic
acid, (42.7 g, 143.2 mmol), DMAP (5.2 g, 42.9 mmol) and DCC (29.5 g, 143.2 mmol).
The resulting suspension was stirred at room temperature until the starting material
was consumed as indicated by TLC. The mixture was filtered and the residue was washed
with dichloromethane. The filtrate was concentrated to produce an oily residue. The
residue was taken up in a minimum amount of dichloromethane and was added drop wise
to vigorously stirred methanol (500 mL) to produce precipitates. The resulting precipitates
were collected by vacuum filtration and washed with a minimum amount of CH
3OH. The precipitate was used directly in the next step.
Step 5
[0144] To a reaction flask containing the precipitate (47 g crude wt) from Step 4 was added
1,2-dichloroethane (300 mL), ethanol (150 mL) and PPTS (10 g). The mixture was heated
to reflux for 18 h until the starting material was consumed as indicated by TLC. The
solvent was removed under vacuum and the residue passed through a silica plug (500
g) and eluted with dichloromethane. Fractions containing the product were grouped
and concentrated to produce an oily residue. The resulting oily residue (31.7 g) was
used directly in the next step.
Step 6
[0145] To reaction flask containing the oily residue (31.7 g, 40.5 mmol) from the previous
step was added dichloromethane (100 mL), DCC (10.0 g, 48.5 mmol), DMAP (2.5 g, 20.5
mmol) and 4-(4-pentylcyclohexyl)benzoic acid (13.0 g, 47.5 mmol). The reaction mixture
was stirred at room temperature until the starting material was consumed as indicated
by TLC. The reaction mixture was filtered and the residue was washed with dichloromethane.
The filtrate was concentrated to produce an oily residue. The oily residue was purified
by passing through a silica plug (500 g) and eluted with hexane:dichloromethane (1:9
volume ratio). Fractions containing the product were combined and concentrated under
vacuum and produced foam. The foam was dissolved in a minimum amount of dichloromethane
and was added drop wise to vigorously stirred methanol (300 mL) to produce precipitates.
The precipitates (15 g) were collected by vacuum filtration and washed with a minimum
amount of methanol. NMR showed that the product had a structure consistent with 3,3-di(4-methoxyphenyl)-13-ethyl-6,13-dimethoxy-7-(4-(4-(4-trans-pentylcyclohexyl)benzoyloxy)phenyl)benzoyloxy-3H,13H-indeno[2',3':3,4]naphtho[1,2-b]pyran.
Example PC-4
Step 1
[0146] To a reaction flask was added 4'-bromoacetophenone (500 g, 2.5 mol), triethylamine
(500 mL) and methylene chloride (1 L). To this stirred mixture, triisopropylsilyl
trifluoromethanesulfonate (784 g, 2.56 mol) was added dropwise using a dropping funnel.
The reaction was exothermic so the temperature was controlled to below boiling by
using an ice bath. After the addition, the reaction mixture was left stirring at room
temperature for 4 hours. Hexanes (1 L) and sodium bicarbonate saturated water solution
(500 ml) was then added to the mixture. The resulting organic layer was collected
using a separatory funnel, washed three times with sodium bicarbonate saturated water
solution, dried over MgSO
4 and then concentrated. The recovered yellow oil was then distilled using a Kugelrohr
apparatus. A clear liquid (890 g) was obtained as the product. NMR showed that the
product had a structure consistent with (1-(4-bromophenyl)vinyloxy)triisopropylsilane.
Step 2
[0147] To a reaction flask was added the product from Step 1 (580 g, 1.63 mol), dimethyl
acetylenedicarboxylate (220 g, 1.55 mol), 2,3,5,6-tetrachloro-(1,4)-benzoquinone (401
g, 1.63 mol) and toluene (1.1 L). The mixture was refluxed for 6 h and then cooled
to room temperature. Hexanes (1 L) were added to the mixture. The solid precipitate
was filtered off. The solution was then concentrated. Brownish oil (980 g) was obtained
and used directly in the next step.
Step 3
[0148] To a reaction flask was added the crude product from Step 2 (980 g), acetic acid
(178 g, 3 mol), and methanol (450 mL). The mixture was stirred at room temperature.
Potassium fluoride (138 g, 2.4 mol) was added in several portions. Half an hour after
the completion of the addition of potassium fluoride, water (2 L) and hexanes (2 L)
were added to the reaction mixture under vigorous stirring. Viscous oil precipitated
from the mixture. The water and hexanes were decanted. The oil was washed several
times with water, dissolved in ethyl acetate (3 L), dried over magnesium sulfate and
concentrated until white crystals started to form. The mixture was then cooled in
an ice bath. The precipitated off-white crystals were collected by vacuum filtration.
NMR showed that the product (198 g) had a structure consistent with dimethyl 7-bromo-4-hydroxynaphthalene-1,2-dicarboxylate.
Step 4
[0149] To a reaction flask was added the product from Step 3 (30 g, 89 mmol), 1,1-diphenylprop-2-yn-1-ol
(18.4 g, 89 mmol), methylene chloride (300 mL) and pTSA (1.68 g, 8.9 mmol). The mixture
was refluxed for 17 hours and then dried over magnesium sulfate. After removal of
most of the solvent, methanol (200 mL) was added. Yellow crystals precipitated and
were collected by vacuum filtration. NMR showed that the product (48 g) had a structure
consistent with dimethyl 8-bromo-5,6-bis(methoxycarbonyl)-2,2-diphenyl-2H-naphtho[1,2-b]pyran.
Step 5
[0150] To a reaction flask was added 4-aminophenylboronic acid pinacolate (52 g, 0.24 mol),
4-(4-pentylcyclohexyl)benzoic acid (65 g, 0.24 mol), methylene chloride (500 mL),
DCC (64.4 g, 0.31 mol) and DMAP (2 g, 16 mmol). The mixture was stirred at room temperature
for a few hours for the reaction to go to completion and stirring was continued for
about 64 hours. Solids were filtered off. The resulting solution was concentrated
until large amount of white crystals formed. Methanol (1 L) was added to the mixture.
The resulting white solid was collected by vacuum filtration (102 g). NMR showed that
the product (48 g) had a structure consistent with 4-(4-pentylcyclohexyl)-N-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)benzamide.
Step 6
[0151] To a reaction flask was added the product from Step 4 (48 g, 91 mmol), the product
from Step 5 (43.1 g, 91 mmol), dichloro-bis(triphenylphosphine)palladium(II) (1.3
g, 2 mmol), potassium fluoride (22 g, 360 mmol), THF (1 L) and water (500 mL). The
mixture was degassed, protected with nitrogen and refluxed. After 17 hours, five more
grams of product from Step 5 was added. Five hours later, the reaction was stopped.
The organic portion was collected using a separatory funnel, dried over magnesium
sulfate and concentrated. A plug column was used to remove the black impurity from
the product. The product was recrystallized from a mixture of the solvents methylene
chloride/methanol by adding the product to methylene chloride heated to below the
boiling point and subsequently adding incremental amounts of methanol heated to below
the boiling point and cooling until crystals were obtained. Slightly yellow crystals
were obtained (57 g). NMR showed that the product (48 g) had a structure consistent
with dimethyl 8-(4-(4-(4-pentylcyclohexyl)benzamido)benzoyloxy-5,6-bis(methoxycarbonyl)-2,2-diphenyl-2H-naphtho[1,2-b]pyran.
Dichroic Dyes
[0152] The following two dichroic dyes, which are available from Mitsubishi Chemical, were
used to prepare individually dichroic dye-colored (i.e., blue or yellow) liquid crystal
monomer solutions (LCMS):
DD-1 is LSR-335 reported to be a blue dye of Lot: 01 C131; and
DD-2 is LSR-120 reported to be a yellow dye of Lot: 2D231.
Examples 8-30
[0153] Examples 8-30 were prepared according to the formulation listed in Table 2 using
the specific LCM, DD and PC listed in Table 3 as described below.
Table 2
| Materials |
Weight Percent (based on the total weight of the solution unless specified otherwise) |
| LCM solids: RM-257(1) |
30 |
| RM-105(2) |
12 |
| LCM-1 thru 7 |
18 |
| Solvent(3) |
40 |
| Initiator(4) |
1.5 based on LCM solids |
| Stabilizer(5) |
0.1 based on LCM solids |
| Dye when present (DD or PC) |
2.0 based on LCM solids |
(1) RM-257 is a liquid crystal monomer available from EMD Chemicals, Inc. and is reported
to have the molecular formula of C33H32O10.
(2) RM-105 is a liquid crystal monomer available from EMD Chemicals, Inc. and is reported
to have the molecular formula of C23H26O6.
(3) Solvent was 99 weight percent anisole and 1 weight percent surfactant sold as
BYK®-346 additive by BYK Chemie, USA.
(4) Initiator was IRGACURE® 819, a photoinitiator that is available from Ciba-Geigy Corporation.
(5) Stabilizer was 2-methyl hydroquinone. |
Table 3
| Example No. |
LCM No. |
Dye |
| 3 * |
2 |
--- |
| 4 |
2 |
PC-3 |
| 5 |
2 |
PC-2 |
| * not an example of the present invention |
[0154] To a vial (20 mL) containing a magnetic stir bar was added each of the liquid crystal
monomers, stabilizer, and initiator. Solvent was added to the contents in the vial,
and the vial was capped and wrapped with aluminum foil and then positioned on a magnetic
stirrer. The resulting mixture was heated to 80°C and stirred for about 30 min until
the solution became clear. The solution was cooled to room temperature and a small
drop of solution was taken by a capillary for phase transition study. If a dye was
required, it was added to the clear solution and heated to 80°C with stirring for
30 min to dissolve. Afterwards, the resulting solution was cooled to room temperature
and stored in darkness.
Comparative Examples (CE) 1-7
[0155] Comparative Examples (CE) 1-7 were prepared following the procedure used for Examples
8-30 except according to the formulation listed in Table 4 using the specific dyes
listed in Table 5.
Table 4
| Materials |
Weight Percent (based on the total weight of the solution unless specified otherwise) |
| LCM solids: RM-257(1) |
32.5 |
| RM-105(2) |
32.5 |
| Solvent(3) |
35 |
| Initiator(4) |
1.5 based on LCM solids |
| Stabilizer(5) |
0.1 based on LCM solids |
| Dye when present (DD or PC) |
2.0 based on LCM solids |
Table 5
| Comparative Example No. |
Dye |
| 1 |
--- |
| 2 |
PC-4 |
| 3 |
PC-3 |
| 4 |
PC-1 |
| 5 |
PC-2 |
| 6 |
DD-2 |
| 7 |
DD-1 |
Example 6- Preparation of Samples Coated with the Examples and Comparative Examples
[0156] The procedures described hereinafter in Parts A-D were followed to prepare at least
partial coatings of the Examples and Comparative Examples on the substrate surfaces.
The phase transitions of each Example and Comparative Example was determined by the
procedure described in Part E.
Part A - Substrate Cleaning
[0157] Square substrates measuring 5.08 cm by 5.08 cm by 0.318 cm (2 inches (in.) by 2 in
by 0.125 in.) prepared from CR-39
® monomer were obtained from Homalite, Inc. Each substrate was cleaned by wiping with
a tissue soaked with acetone and dried with a stream of nitrogen gas.
Part B - Alignment Layer Application
[0158] A solution of a photo-orientable polymer network, available as STARALIGN® 2200 CP10
solution from Huntsman Advanced Materials, was diluted to 4 weight percent in cyclopentanone.
The resulting solution was applied by spin-coating to a portion of the surface of
the test substrate by dispensing approximately 1.0 mL of the STARALIGN® solution and
spinning the substrates at 1000 revolutions per minute (rpm) for 10 seconds. Afterwards,
the coated substrates were placed in an oven maintained at 135°C. for 30 minutes.
[0159] For the alignment layer produced by rubbing, triacetate cellulose (TAC) was dissolved
in cyclopentanone at 4 weight percent and applied by spin-coating to a portion of
the surface of the test substrate by dispensing approximately 1.0 mL of the TAC solution
and spinning the substrates at 500 rpm for 3 seconds followed by 1000 rpm for 10 seconds.
Afterwards, the coated substrates were placed in an oven maintained at 140°C for 60
minutes.
Part C - Orientation of the Alignment Layer
[0160] After application, the photo-orientable polymer network was at least partially ordered
by exposure to linearly polarized ultraviolet radiation for 5 minute at a peak intensity
of 80-100 Watts/m
2 of UVA (320-390 nm) as measured using International Light Research Radiometer, Model
IL-1700 with a detector system comprising a Model SED033 detector, B Filter and diffuser.
The output display of the radiometer was corrected (factor values set) against a Licor
1800-02 Optical Calibration Calibrator in order to display values representing Watts
per square meter UVA. The source of linearly polarized UV radiation was a mercury
arc lamp (Model 69910) from Newport Oriel equipped with an intensity controller Model
68951. The light source was oriented such that the radiation was linearly polarized
in a plane perpendicular to the surface of the substrate. After ordering at least
a portion of the photo-orientable polymer network, the substrates were cooled to room
temperature and kept covered.
[0161] The substrates having the TAC layer were oriented by rubbing the coated surface with
velvet uni-directionally 20 times.
Part D - Application of the Examples and Comparative Examples
[0162] Prior to application, 10 weight percent of MgSO
4 was added to each of the Examples and Comparative Examples and the resulting mixture
was stirred for an hour at room temperature and subject to centrifuge filtration using
a Millipore Ultrafree-MC (Durapore PVDF 5 um) filtration device in a Sorvall Legend
Micro 21 centrifuge at 10,000 rpm for 5 min. A small drop of filtrate was taken by
a capillary for phase transition study. Material not used for the subsequent coating
step was stored in darkness.
[0163] The Examples and Comparative Examples were applied by spin-coating to the aligned
layer on the substrates by spin-coating to a portion of the surface of the test substrate
by dispensing 400 µL of the solution and spinning the substrates at 400 rpm for 9
seconds followed by 800 rpm for 15 seconds. A spin processor from Laurell Technologies
Corp. (WS-400B-6NPP/LITE) was used for spin coating. Afterwards, the coated substrates
were placed in a convection oven maintained at 5°C to 10 °C lower than the corresponding
clearing temperature (the temperature at which the liquid crystals transform into
the isotropic state, as indicated in Table 6) for 10 to 15 minutes followed by curing
under an ultraviolet lamp in the Irradiation Chamber BS-03 from Dr. Gröbel in a nitrogen
atmosphere for 30 minutes at a peak intensity of 11-16 Watts/m
2 of UVA.
Part E - Measurement of Liquid Crystal Phase Transition Temperatures
[0164] Phase transition temperatures were determined by using a Leica DM 2500 M polarized
optical microscope equipped with a Linkam LTS 120 hot stage and a Linkam PE 94 temperature
controller. A small drop of solution from a capillary pipette was placed on a microscope
glass slide, and a stream of nitrogen was used to evaporate the solvent. The glass
slide was mounted on the sample stage so that the liquid crystal residue spot was
in the optical path of the microscope. Phase transition temperatures were measured
by observing the samples during heating at a rate of 10ºC/min starting at 25ºC. Phase
below 25ºC was not determined. The sample was heated until it reached the isotropic
phase and then cooled at 10 ºC/min to 25ºC to determine the phase transition temperatures
during the cooling process as indicated in Table 6. The phases of the liquid crystals
were determined according to the texture that appeared during the heating and cooling
processes.
Textures of Liquid Crystals by Dietrich Demus and Lothar Richter, published by Verlag
Chemie, Weinheim & New York in 1978 was used in the identification of the different liquid crystal phases listed in Table
6.
[0165] The following abbreviations were used in the table: N represents the Nematic phase;
I represents the Isotropic phase. Note that all numbers represent the temperature
in ºC at which the adjacent phase abbreviation occurred. Each phase measured is separated
by // meaning that the phase extended until the next temperature or temperature range
listed. For example, 25 N // 37 i, indicates that the Nematic phase was present from
25ºC to about 37ºC when the Isotropic phase occurred. Observation of the sample's
phase started at room temperature (25ºC) and reported the next phase transition temperature.
Table 6
| Example No. |
Phase Transition Temperature |
| Example 3 |
25 N // 62 I // 56 N |
| Example 4 |
25 N //58 I // 53 N |
| Example 5 |
25 N // 48 I // 44 N |
| CE 1 |
25 N // 83 I // 74 N |
| CE 2 |
25 N // 80 I // 72 N |
| CE 3 |
25 N // 78 I // 70 N |
| CE 4 |
25 N // 75 I // 65 N |
| CE 5 |
25 N // 76 I // 67 N |
| CE 6 |
25 N // 83 I // 75 N |
| CE 7 |
25 N // 78 I // 72 N |
Part F - Absorption Ratio and Optical Response Measurements
[0166] Absorption ratios for each of the substrates having coating containing dichroic dyes
(DD) were determined as follows. A Cary 6000i UV-Visible spectrophotometer was equipped
with a self-centering sample holder mounted on a rotation stage (Model M-060-PD from
Polytech, PI) and the appropriate software. A polarizer analyzer (Moxtek PROFLUX®
polarizer) was placed in the sample beam before the sample. The instrument was set
with the following parameters: Scan speed = 600 nm/min; Data interval = 1.0 nm; Integration
time = 100 ms; Absorbance range = 0-6.5; Y mode = absorbance; X-mode = nanometers;
and the scanning range was 380 to 800 nm. Options were set for 3.5 SBW (slit band
width), and double for beam mode. Baseline options were set for Zero/baseline correction.
Also, 1.1 and 1.5 (∼2.6 together) Screen Neutral Density filters were in the reference
path for all scans. The coated substrate samples were tested in air, at room temperature
(22.7ºC ± 2.4ºC) maintained by the lab air conditioning system.
[0167] Orientation of the sample polarizer to be parallel and perpendicular to the analyzer
polarizer was accomplished in the following manner. The Cary 6000i was set to 443
nm for samples containing DD-2 and 675 nm for samples containing DD-1, and the absorbance
was monitored as the sample was rotated in small increments (0.1 to 5 degrees, e.g.,
5, 1, 0.5 and 0.1 degrees). The rotation of the sample was continued until the absorbance
was maximized. This position was defined as the perpendicular or 90 degree position.
The parallel position was obtained by rotating the stage 90 degrees clock-wise or
counter-clockwise. Alignment of the samples was achieved to ± 0.1º.
[0168] The absorption spectra were collected at both 90 and 0 degrees for each sample. Data
analysis was handled with the Igor Pro software available from WaveMetrics. The spectra
were loaded into Igor Pro and the absorbances were used to calculate the absorption
ratios at 443 nm and 675 nm. The calculated absorption ratios are listed in Table
7.
[0169] The λ
max-vis in the visible light range is the wavelength in the visible spectrum at which the
maximum absorption of the activated form of the photochromic compound or dichroic
dye occurs. The λ
max-vis was determined by testing the coated substrate in a Cary 6000i UV-Visible spectrophotometer.
[0170] Prior to response testing on an optical bench, the substrates having photochromic
compounds in the coatings were conditioned by exposing them to 365 nm ultraviolet
light for 10 minutes at a distance of about 14 cm from the source in order to preactivate
the photochromic molecules. The UVA irradiance at the sample was measured with a Licor
Model Li-1800 spectroradiometer and found to be 22.2 Watts per square meter. The samples
were then placed under a halogen lamp (500 W, 120 V) for about 10 minutes at a distance
of about 36 cm from the lamp in order to bleach, or inactivate, the photochromic compound
in the samples. The illuminance at the sample was measured with the Licor spectroradiometer
and found to be 21.9 Klux. The samples were then kept in a dark environment for at
least 1 hour prior to testing in order to cool and continue to fade back to a ground
state.
[0171] An optical bench was used to measure the optical properties of the coated substrates
and derive the absorption ratio and photochromic properties. Each test sample was
placed on the optical bench with an activating light source (a Newport/Oriel Model
66485 300-Watt Xenon arc lamp fitted with a UNIBLlTZ® VS-25 high-speed computer controlled
shutter that momentarily closed during data collection so that stray light would not
interfere with the data collection process, a SCHOTT® 3 mm KG-1 band-pass filter,
which removed short wavelength radiation, neutral density filter(s) for intensity
attenuation and a condensing lens for beam collimation) positioned at a 30° to 35°
angle of incidence to the surface of the test sample. The arc lamp was equipped with
a light intensity controller (Newport/Oriel model 68950).
[0172] A broadband light source for monitoring response measurements was positioned in a
perpendicular manner to a surface of the test sample. Increased signal of shorter
visible wavelengths was obtained by collecting and combining separately filtered light
from a 100-Watt tungsten halogen lamp (controlled by a LAMBDA® UP60-14 constant voltage
powder supply) with a split-end, bifurcated fiber optical cable. Light from one side
of the tungsten halogen lamp was filtered with a SCHOTT® KG1 filter to absorb heat
and a HOYA® B-440 filter to allow passage of the shorter wavelengths. The other side
of the light was either filtered with a SCHOTT® KG1 filter or unfiltered. The light
was collected by focusing light from each side of the lamp onto a separate end of
the split-end, bifurcated fiber optic cable, and subsequently combined into one light
source emerging from the single end of the cable. A 4" light pipe was attached to
the single end of the cable to insure proper mixing. The broad band light source was
fitted with a UNIBLITZ® VS-25 high-speed computer controlled shutter that momentarily
opened during data collection.
[0173] Polarization of the light source was achieved by passing the light from the single
end of the cable through a Moxtek, PROFLUX® Polarizer held in a computer driven, motorized
rotation stage (Model M-061-PD from Polytech, PI). The monitoring beam was set so
that the one polarization plane (0°) was perpendicular to the plane of the optical
bench table and the second polarization plane (90°) was parallel to the plane of the
optical bench table. The samples were run in air, at 23ºC ± 0.1ºC maintained by a
temperature controlled air cell.
[0174] To align each sample, a second polarizer was added to the optical path. The second
polarizer was set to 90º of the first polarizer. The sample was placed in an air cell
in a self-centering holder mounted on a rotation stage (Model No M-061. PD from Polytech,
PI). A laser beam (Coherent -ULN 635 diode laser) was directed through the crossed
polarizers and sample. The sample was rotated (in 3º steps as course moves and in
0.1º steps as fine moves) to find the minimum transmission. At this point the sample
was aligned either parallel or perpendicular to the Moxtek polarizer and the second
polarizer as well as the diode laser beam was removed from the optical path. The sample
was aligned ± 0.2º prior to any activation.
[0175] To conduct the measurements, each test sample containing a photochromic dye was exposed
to 6.7 W/m
2 of UVA from the activating light source for 10 to 20 minutes to activate the photochromic
compound. An International Light Research Radiometer (Model IL-1700) with a detector
system (Model SED033 detector, B Filter, and diffuser) was used to verify exposure
at the beginning of each day. Light from the monitoring source that was polarized
to the 0°polarization plane was then passed through the coated sample and focused
into a 1" integrating sphere, which was connected to an OCEAN OPTICS® S2000 spectrophotometer
using a single function fiber optic cable. The spectral information, after passing
through the sample, was collected using OCEAN OPTICS® OOIBase32 and OOIColor software,
and PPG propriety software. While the photochromic material was activated, the position
of the polarizing sheet was rotated back and forth to polarize the light from the
monitoring light source to the 90 ° polarization plane and back. Data was collected
for approximately 600 to 1200 seconds at 5-second intervals during activation. For
each test, rotation of the polarizers was adjusted to collect data in the following
sequence of polarization planes: 0°, 90°, 90°, 0°, etc.
[0176] Absorption spectra were obtained and analyzed for each test sample using the Igor
Pro software (available from WaveMetrics). The change in the absorbance in each polarization
direction for each test sample was calculated by subtracting out the 0 time (i.e.,
unactivated) absorption measurement for the samples at each wavelength tested. Average
absorbance values were obtained in the region of the activation profile where the
photochromic response of the photochromic compound was saturated or nearly saturated
(i.e., the regions where the measured absorbance did not increase or did not increase
significantly over time) for each sample by averaging absorbance at each time interval
in this region. The average absorbance values in a predetermined range of wavelengths
corresponding λ
max-vis +/- 5 nm were extracted for the 0° and 90° polarizations, and the absorption ratio
for each wavelength in this range was calculated by dividing the larger average absorbance
by the small average absorbance. For each wavelength extracted, 5 to 100 data points
were averaged. The average absorption ratio for the photochromic compound was then
calculated by averaging these individual absorption ratios.
[0177] Change in optical density (ΔOD) from the bleached state to the darkened state was
determined by establishing the initial transmittance, opening the shutter from the
xenon lamp to provide ultraviolet radiation to change the test lens from the bleached
state to an activated (i.e., darkened) state. Data was collected at selected intervals
of time, measuring the transmittance in the activated state, and calculating the change
in optical density according to the formula: ΔOD = log(%Tb/%Ta), where %Tb is the
percent transmittance in the bleached state, %Ta is the percent transmittance in the
activated state and the logarithm is to the base 10.
[0178] The fade half life (T1/2) is the time interval in seconds for the ΔOD of the activated
form of the photochromic compound in the test samples to reach one half the ΔOD measured
after fifteen minutes, or after saturation or near-saturation was achieved, at room
temperature after removal of the source of activating light, e.g., by closing the
shutter. The results of these tests are presented in Table 7.
Table 7
| Example No. |
λmax-vis (nm) |
Absorption Ratio |
T ½ (seconds) |
| Example 4 |
579 |
3.78 |
167 |
| Example 5 |
586 |
1.20 |
85 |
| CE 2 |
466 |
6.79 |
3042 |
| CE 3 |
581 |
4.72 |
>3600 |
| CE 4 |
559 |
1.25 |
1065 |
| CE 5 |
585 |
1.33 |
1590 |
| CE 6 |
443 |
7.28 |
--- |
| CE 7 |
678 |
5.18 |
--- |