Technical Field
[0001] This invention relates to gel compositions containing a silicone elastomer from the
reaction of an organohydrogensiloxane having at least two SiH containing cyclosiloxane
rings in its molecule, a compound, or mixture of compounds having at least two aliphatic
unsaturated hydrocarbon groups in its molecule, and a hydrosilylation catalyst. The
silicone elastomer reaction product may itself be a gelled composition, or optionally
may be contained in a carrier fluid to form a gel. The gel compositions may further
contain a personal or healthcare active. The actives may be incorporated into the
gel via either a pre or post load method.
Background
[0002] Silicone elastomers have been used extensively in personal care applications for
their unique silky and powdery sensory profile. Most of these elastomers can gel volatile
silicone fluids as well as low polarity organic solvents such as isododecane. Representative
examples of such silicone elastomers are taught in
US Patent 5,880,210, and
US 5,760,116. To improve compatibilities of silicone elastomers with various personal care ingredients,
alkyls, polyether, amines or other organofunctional groups have been grafted onto
the silicone elastomer backbone. Representative of such organofunctional silicone
elastomers are taught in
US 5,811,487 ,
US 5,880,210,
US 6,200,581,
US 5,236,986,
US 6,331,604,
US 6,262,170,
US 6,531,540, and
US 6,365,670. Many of these silicone elastomers have limited compatibilities with various personal
care ingredients, personal care actives and healthcare actives. These elastomers loose
thickening and gelling efficiency, and even sensory benefits in the presence of personal
care ingredients, personal care actives and healthcare actives. There is a need to
further improve compatibilities of silicone elastomers with various personal care
ingredients and actives.
[0003] However, there is still a need to further improve the efficiency of gelling volatile
cosmetic fluids such as volatile silicones by silicone elastomers, and in particular
to improve the rheological thickening effects by the addition of silicone elastomers
to volatile cosmetic fluids. Furthermore, additional benefits are also sought for
gelled compositions, such as improving the clarity of gelled silicone compositions
and/or improved aesthetics upon application on skin.
[0004] The present inventors have discovered that silicone elastomers derived from cyclic
organohydrogensiloxanes provide gelled compositions efficiently. The resulting gelled
compositions also possess additional benefits, such as improved aesthetics and improved
compatibilities with personal care ingredients and actives.
Summary
[0005] This disclosure relates to a gel composition comprising a silicone elastomer from
the reaction of;
- A) an organohydrogensiloxane having at least two SiH containing cyclosiloxane rings
in its molecule
- B) a compound or mixture of compounds having at least two aliphatic unsaturated hydrocarbon
groups in its molecule,
- C) a hydrosilylation catalyst,
and;
- D) an optional carrier fluid.
[0006] This disclosure further relates to a process for preparing a silicone elastomer gel
containing an active comprising:
- I) reacting;
a) an organohydrogencyclosiloxane having at least two SiH units on a siloxane ring,
B) a compound or mixture of compounds having at least two aliphatic unsaturated hydrocarbon
groups in its molecule,
C) a hydrosilylation catalyst,
to form
- A) an organohydrogensiloxane having at least two SiH containing cyclosiloxane rings
in its molecule,
wherein the molar ratio of the SiH units of component a) to the aliphatic unsaturated
groups of component B) ranges from 2/1 to 8/1,
- II) further reacting;
- A) the organohydrogensiloxane having at least two SiH containing cyclosiloxane rings
in its molecule, with additional quantities of
- B) the compound or mixture of compounds containing at least two aliphatic unsaturated
groups in its molecules,
- C) the hydrosilylation catalyst,
in the presence of
D) an optional carrier fluid, and
E) a personal care or healthcare active,
to form the silicone elastomer gel.
[0007] A personal care or healthcare active may be incorporated into the silicone organic
elastomer gel by having it be present during the formation of the silicone organic
elastomer gel (pre-load method) or admixing it with a formed silicone organic elastomer
gel (post-load method).
Detailed Description
(A) The organohydrogensiloxane having at least two SiH containing cyclosiloxane rings
[0008] Component (A) in the present invention is an organohydrogensiloxane having at least
two SiH containing cyclosiloxane rings in its molecule. Organohydrogensiloxanes suitable
as component A) in the present invention are any organopolysiloxanes having in its
molecule at least two cyclosiloxane rings with at least one silicon bonded hydrogen
(SiH) unit on each siloxane ring. Organopolysiloxanes are well known in the art and
are often designated as comprising any number of (R
3SiO
0.5), (R
2SiO), (RSiO
1.5), or (SiO
2) siloxy units where R is independently any organic group. When R is methyl in the
siloxy unit formulas of an organopolysiloxane, the respective siloxy units are often
designated as M, D, T or Q siloxy units. Cyclosiloxane rings contain at least three
siloxy units (that is the minimum needed in order to form a siloxane ring), and may
be any combination of (R
3SiO
0.5), (R
2SiO), (RSiO
1.5), or (SiO
2) siloxy units that forms a cyclic structure, providing at least one of the cyclic
siloxy units on each siloxane ring contains one SiH unit, that is there is at least
one (R
2HSiO
0.5), (RHSiO), or a (HSiO
1.5) siloxy unit present in the ring. These siloxy units can be represented as M
H, D
H, and T
H siloxy units respectively when R is methyl.
[0009] The cyclosiloxane rings of A) the organohydrogensiloxane are linked together by a
divalent organic or siloxane group, or combination thereof. The divalent linking group
may be designated as Y and the cyclosiloxane as G. Thus, the organohydrogensiloxane
of the present invention may be represented by the general formula G-[Y-G]
a, where G is a cyclosiloxane as described above and Y is a divalent organic, a siloxane,
a polyoxyalkylene group, or combination thereof, and the subscript a is greater than
zero.
[0010] When Y is a divalent organic, it may be a divalent hydrocarbon containing 1 to 30
carbons, either as aliphatic or aromatic structures, and may be branched or un-branched.
Alternatively, Y can be an alkylene group containing 2 to 20 carbons, or alternatively
containing 4 to 12 carbons.
[0011] When Y is a divalent organic, it may also be selected from an organic polymer, such
as a polyoxyalkylene group.
[0012] When Y is a siloxane group it may be selected from any organopolysiloxane containing
at least two divalent hydrocarbon groups, designated as R
1. Thus, the siloxane linking group can be any organopolysiloxane comprising at least
two siloxane units represented by the average formula R
1 R
mSiO
(4-m)
/2
wherein
R is an organic group,
R1 is a divalent hydrocarbon, and
m is zero to 3
The R
1 group may be present on any mono, di, or tri-siloxy unit in an organopolysiloxane
molecule, for example; (R
1R
2SiO
0.5), (R
1RSiO), or (R
1SiO
1.5), as well as in combination with other siloxy units not containing an R
1 substituent, such as (R
3SiO
0.5), (R
2SiO), (RSiO
1.5), or (SiO
2) siloxy units where R is independently any organic group providing there are at least
two R
1 substituents in the organopolysiloxane. Representative R
1 groups include; ethylene, propylene, butylene, isobutylene, hexylene, and similar
homologs. Alternatively, R
1 is ethylene.
[0013] Representative, non-limiting, examples of such siloxane based structures suitable
as siloxanes linking groups include;
(R
2R
1SiO
0.5)(R
2SiO)
x(R
2R
1SiO
0.5)
(R
3SiO
0.5)(R
2SiO)
x(R
1RSiO)
y(R
3SiO
0.5)
(R
3SiO
0.5)(R
2SiO)
x(R
1RSiO)
y(RSiO
1.5)
z(R
3SiO
0.5)
where x ≥ 0, y ≥ 2, and z is ≥ 0
[0014] Organohydrogensiloxane having at least two SiH containing cyclosiloxane rings (component
A) may be prepared via a hydrosilylation reaction of
a) an organohydrogencyclosiloxane having at least two SiH units on the siloxane ring
and,
B) a compound or mixture of compounds having at least two aliphatic unsaturated groups
in its molecule.
The organohydrogencyclosiloxane (a) having at least two SiH units on the siloxane
ring may contain any number of siloxy units (as defined above) provided there are
at least two SiH units on the cyclosiloxane ring. For example, the cyclic siloxane
can comprise any number of M, M
H, D, D
H, or T
H siloxy units. Representative, non-limiting examples of such organohydrogencyclosiloxanes
useful to prepare component (A) have the average formula D
HaD
b where a is ≥ 1 and b is ≥ 0, and a + b ≥ 3. Alternatively, the organohydrogencyclosiloxane
may be selected from those having the formula [(CH
3)HSiO]
g where g is 3 - 8, such as D
H4, D
H5, D
H6, or mixtures thereof.
[0015] Suitable compounds containing at least two aliphatic unsaturated hydrocarbon groups
in its molecule are described below as component B).
[0016] Hydrosilylation reactions involving organohydrogensiloxanes and unsaturated compounds
are well known. Any suitable Hydrosilylation catalysts know in the art may be used,
or alternatively may be selected from those described below as component C). Any of
the known hydrosilylation techniques and reactions may be employed to prepare component
A) from i) organohydrogencyclosiloxane having at least two SiH units on the siloxane
ring and, B) a compound or mixture of compounds having at least two aliphatic unsaturated
groups in its molecule. However, the reaction is conducted in such a manner to provide
an organohydrogensiloxane having at least two SiH containing cyclosiloxane rings in
its molecule.
[0017] Thus, component A of the present invention contains at least two silicon-bonded hydrogen
atom per molecule, alternatively at least 4 silicon-bonded hydrogen atoms per molecule,
or alternatively at least 6 silicon-bonded hydrogen atoms per molecule. This can be
accomplished by using in the hydrosilylation reaction a molar excess of the a) the
organohydrogencyclosiloxane having at least two SiH units on the siloxane ring vs.
the compound containing at least two aliphatic unsaturated groups in its molecule.
The molar excess may be expressed as the molar ratio of SiH units to unsaturated group,
such ratio may range from 2/1 to 8/1, alternatively from 2/1 to 6/1, or alternatively
from 3/1 to 4/1.
[0018] Alternatively, the organohydrogensiloxane useful as component A) may be selected
from any of the organohydrogensiloxanes taught in
WO03/093349.
[0019] The organohydrogensiloxane useful as component A) in the present invention typically
have a viscosity from 5 to 50,000 mPa·s, alternatively from 10 to 10,000 mPa·s, or
alternatively from 25 to 2,000 mPa·s.
[0020] Representative, non-limiting examples of component A) include;

[0021] Additives known as inhibitors or stabilizers may be added to component A). Inhibitors
such as those described in
WO 03/093369 may be added for the purpose of stabilizing component A) during storage, or prior
to the addition of component B) to prepare the silicone elastomer gel. The inhibitor
may be selected from any compound known to have inhibiting effects of platinum based
hydrosilylation reactions. Examples of known inhibitors include triphenyl phosphate,
tocopherol (vitamin E), and butylated hydroxy toluene. A particularly preferred inhibitor
is vitamin A palpitate, or VAP. When VAP is used, it is typically added at 0.05 to
2.0 parts per 100 parts of component A).
(B) The Compound or mixture of compounds having at least two aliphatic unsaturated
hydrocarbon groups in its molecule
[0022] Component (B) is a compound, or any mixture of compounds, containing at least two
aliphatic unsaturated groups in its molecule. The compound may be any diene, diyne
or ene-yne compound. Diene, diyne or ene-yne compounds are those compounds (including
polymeric compounds) wherein there are at least two aliphatic unsaturated groups with
some separation between the groups within the molecule. Typically, the unsaturation
groups are at the termini of the compound, or pendant if part of a polymeric compound.
Compounds containing terminal or pendant unsaturated groups can be represented by
the formula R
2-Y-R
2 where R
2 is a monovalent unsaturated aliphatic hydrocarbon group containing 2 to 12 carbon
atoms, and Y is a divalent organic or siloxane group or a combination of these. Typically
R
2 is CH
2=CH-, CH
2=CHCH
2-, CH
2=CH(CH
2)
4-, CH
2=C(CH
3)CH
2- or CH≡C-, and similar substituted unsaturated groups such as H
2C=C(CH
3) -, and HC≡C(CH
3)-.
[0023] The compound having the formula R
2-Y-R
2 as component B) may be considered as being a "organic", "hydrocarbon", "organic polymer",
"polyether" or "siloxane", or combinations thereof, depending on the selection of
Y. Y may be a divalent hydrocarbon, a siloxane, a polyoxyalkylene, a polyalkylene,
a polyisoalkylene, a hydrocarbon-silicone copolymer, or mixtures thereof.
[0024] In one embodiment, the component (B) is selected from an organic compound, herein
denoted as (B
1), having the formula R
2-Y
1- R
2 where R
2 is a monovalent unsaturated aliphatic group containing 2 to 12 carbon atoms and Y
1 is a divalent hydrocarbon,. The divalent hydrocarbon Y
1 may contain 1 to 30 carbons, either as aliphatic or aromatic structures, and may
be branched or un-branched. Alternatively, the linking group Y
1 in B
1 may be an alkylene group containing 1 to 12 carbons. Component (B
1) may be selected from α, ω - unsaturated alkenes or alkynes containing 1 to 30 carbons,
and mixtures thereof. Component (B
1) may be exemplified by, but not limited to 1,4-pentadiene, 1,5-hexadiene; 1,6-heptadiene;
1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, 1,11-dodecadiene, 1,13-tetradecadiene,
and 1,19-eicosadiene, 1,3-butadiyne, 1, 5-hexadiyne (dipropargyl), and 1-hexene-5-yne.
[0025] In another embodiment, the component (B) is selected from a R
2-Y
2- R
2 compound where Y
2 is a siloxane, herein denoted as (B
2). The Y
2 siloxane group may be selected from any organopolysiloxane bonded to at least two
organic groups having aliphatic unsaturation, designated as R
2, to form R
2-Y
2- R
2 structures. Thus, component (B
2) can be any organopolysiloxane, and mixtures thereof, comprising at least two siloxane
units represented by the average formula R
2 R
mSiO
(4-m)/2
wherein
R is an organic group,
R2 is a monovalent unsaturated aliphatic group as defined above, and
m is zero to 3
[0026] The R
2 group may be present on any mono, di, or tri siloxy unit in an organopolysiloxane
molecule, for example; (R
2R
2SiO
0.5), (R
2RSiO), or (R
2SiO
1.5)
; as well as in combination with other siloxy units not containing an R
2 substituent, such as (R
3SiO
0.5), (R
2SiO), (RSiO
1.5), or (SiO
2) siloxy units where R is independently any organic group, alternatively a hydrocarbon
containing 1 to 30 carbons, alternatively an alkyl group containing 1 to 30 carbons,
or alternatively methyl; providing there are at least two R
2 substituents in the organopolysiloxane.
[0027] Representative, non-limiting, examples of such siloxane based R
2-Y
2- R
2 structures suitable as component (B
2) include;
(R
2R
2SiO
0.5)(SiO
2)
w(R
2R
2SiO
0.5)
(R
2R
2SiO
0.5) (SiO
2)
w(R
2SiO)
x(R
2R
2SiO
0.5)
(R
2R
2SiO
0.5)(R
2SiO)
x(R
2R
2SiO
0.5)
(R
3SiO
0.5)(R
2SiO)
x(R
2RSiO)
y(R
3SiO
0.5)
(R
3SiO
0.5)(R
2SiO)
x(R
2RSiO)
y(RSiO
1.5)
z(R
3SiO
0.5)
(R
3SiO
0.5)(R
2SiO)
x(R
2RSiO)
y(SiO
2)
w(R
3SiO
0.5)
where w ≥ 0, x ≥ 0, y ≥ 2, and z is ≥ 0, R is an organic group, and
R2 is a monovalent unsaturated aliphatic hydrocarbon group.
[0028] B
2 may be selected from vinyl functional polydimethylsiloxanes (vinyl siloxanes) or
hexenyl functional polydimethylsiloxanes (hexenyl siloxanes), such as those having
the average formula;
CH
2=CH(Me)
2SiO[Me
2SiO]
xSi(Me)
2CH=CH
2
CH
2=CH-(CH
2)
4-(Me)
2SiO[Me
2SiO]
xSi(Me)
2-(CH
2)
4-CH=CH
2
Me
3SiO[(Me)
2SiO]
x[CH
2H(Me)SiO]
ySiMe
3
wherein Me is methyl,
x ≥ 0, alternatively x is 0 to 200, alternatively x is 10 to 150,
y ≥ 2, alternatively y is 2 to 50, alternatively y is 2 to 10.
Vinyl functional polydimethylsiloxanes are known, and there are many commercially
available.
[0029] In another embodiment, component (B) is selected from a polyether compound, herein
denoted as (B
3), having the formula R
2-Y
3- R
2 compound where R
2 is as defined above and Y
3 is a polyoxyalkylene group having the formula (C
nH
2nO)
b wherein n is from 2 to 4 inclusive, b is greater than 2, alternatively b can range
from 2 to 200, or alternatively b can range from 2 to 100.
The polyoxyalkylene group typically can comprise oxyethylene units (C
2H
4O), oxypropylene units (C
3H
6O), oxybutylene or oxytetramethylene units (C
4H
8O) or mixtures thereof. Thus, the R
2-Y
3- R
2 compound may be selected from a polyoxyalkylene group having the formula R
2-[(C
2H
4O)
c(C
3H
6O)
d(C
4H
8O)
e]-R
2 where c, d, and e may each independently range from 0 to 200, providing the sum of
c + d + e is greater than 2, alternatively the sum of c + d + e ranges from 2 to 200,
or alternatively the sum of c + d + e ranges from 2 to 100.
[0030] Alternatively, the polyoxyalkylene group comprises only oxypropylene units (C
3H
6O)
d. Representative, non-limiting examples of polyoxypropylene containing R
2-Y
3- R
2 compounds include;
H
2C=CHCH
2[C
3H
6O]
dCH
2CH=CH
2
H
2C=CH[C
3H
6O]
dCH=CH
2
H
2C=C(CH
3)CH
2[C
3H
6O]
dCH
2C(CH
3)=CH
2
HC≡CCH
2[C
3H
6O]
dCH
2C≡CH
HC≡CC(CH
3)
2[C
3H
6O]
dC(CH
3)
2C≡CH
where d is as defined above.
Representative, non-limiting examples of polyoxybutylene or poly(oxytetramethylene)
containing R
2-Y
3- R
2 compounds include;
H
2C=CHCH
2[C
4H
8O]
eCH
2CH=CH
2
H
2C=CH[C
4H
8O]
eCH=CH
2
H
2C=C(CH
3)CH
2[C
4H
8O]
eCH
2C(CH
3)=CH
2
HC=CCH
2[C
4H
8O]
eCH
2C≡CH
HC≡CC(CH
3)
2[C
4H
8O]
eC(CH
3)
2C≡CH
Component B) may also be a mixture of various polyethers, i.e. a mixture of B
3 components.
[0031] In another embodiment, component (B) is selected from a R
2-Y
4- R
2 compound, herein denoted as (B
4), where R
2 is as defined above and Y
4 is a polyalkylene group, selected from C2 to C6 alkylene units or their isomers.
One example is polyisobutylene group which is a polymer containing isobutylene unit.
The molecular weight of the polyisobutylene group may vary, but typically ranges from
100 to 10,000 g/mole. Representative, non-limiting examples of R
2-Y-R
2 compounds containing a polyisobutylene group includes those obtained from BASF under
the tradename of OPPONOL BV, such as OPPONOL BV 5K, a diallyl terminated polyisobutylene
having an average molecular weight of 5000 g/mole.
[0032] In yet another embodiment, component (B) is selected from a R
2-Y
5- R
2 compound, herein denoted as (B
5), where R
2 is as defined above and Y
5 is a hydrocarbon-silicone copolymer group. The hydrocarbon-silicone copolymer group
may have the formula
-[R
1u(R
2SiO)
v]
q-
where R1 and R are as defined above;
u and v are independently 1, alternatively u ranges from 1 to 20, alternatively v
ranges from 2 to 500, or from 2 to 200,
q is >1, alternatively q ranges from 2 to 500, alternatively q ranges from 2 to 100.
R
2-Y
5-R
2 compounds having a hydrocarbon-silicone copolymer group may be prepared via a hydrosilylation
reaction between an α-ω unsaturated hydrocarbon, such as those described above as
B
1, and an organohydrogensiloxane. A representative, non-limiting example of such a
reaction is shown below.

[0033] Component (B) may also be a mixture of any diene, diyne or ene-yne compound, such
as any combinations of B
1, B
2 , B
3, B
4, and B
5.
[0034] The amounts of component (A) and component (B) used to prepare the present composition
will depend on the individual components and the desired SiH to aliphatic unsaturation
ratio. The ratio of SiH in component (A) to aliphatic unsaturation from component
(B) useful to prepare the compositions of the present invention can be from 10:1 to
1:10, alternatively 5:1 to 1:5, or alternatively 4:1 to 1:4.
[0035] If components (A) and (B) are not the only materials containing aliphatic unsaturated
groups and SiH-containing groups in the present composition, then the above ratios
relate to the total amount of such groups present in the composition rather than only
those components.
(C) The Hydrosilylation Catalyst
[0036] Component (C) comprises any catalyst typically employed for hydrosilylation reactions.
It is preferred to use platinum group metal-containing catalysts. By platinum group
it is meant ruthenium, rhodium, palladium, osmium, iridium and platinum and complexes
thereof. Platinum group metal-containing catalysts useful in preparing the compositions
of the present invention are the platinum complexes prepared as described by
Willing, U. S. Pat. No. 3,419,593, and
Brown et al, U. S. Pat. No. 5,175,325. Other examples of useful platinum group metal-containing catalysts can be found
in
Lee et al., U. S. Pat. No. 3,989,668;
Chang et al., U. S. Pat. No. 5,036,117;
Ashby, U. S. Pat. No. 3,159,601;
Lamoreaux, U. S. Pat. No. 3,220,972;
Chalk et al., U. S. Pat. No. 3,296,291;
Modic, U.S. Pat. No. 3,516,946;
Karstedt, U. S. Pat. No. 3,814,730; and
Chandra et al., U. S. Pat. No. 3,928,629, all of which show useful platinum group metal-containing catalysts and methods for
their preparation. The platinum-containing catalyst can be platinum metal, platinum
metal deposited on a carrier such as silica gel or powdered charcoal, or a compound
or complex of a platinum group metal. Preferred platinum-containing catalysts include
chloroplatinic acid, either in hexahydrate form or anhydrous form, and or a platinum-containing
catalyst which is obtained by a method comprising reacting chloroplatinic acid with
an aliphatically unsaturated organosilicon compound such as divinyltetramethyldisiloxane,
or alkene-platinum-silyl complexes as described in
U.S. Patent Application No. 2003/0109 732, such as (COD)Pt(SiMeCl
2)
2, where COD is 1,5-cyclooctadiene and Me is methyl. These alkene-platinum-silyl complexes
may be prepared, for example by mixing 0.015 mole (COD)PtCl
2 with 0.045 mole COD and 0.0612 moles HMeSiCl
2.
[0037] The appropriate amount of the catalyst will depend upon the particular catalyst used.
The platinum catalyst should be present in an amount sufficient to provide at least
2 parts per million (ppm), preferably 4 to 200 ppm of platinum based on total weight
percent solids (all non-solvent ingredients) in the composition. It is highly preferred
that the platinum is present in an amount sufficient to provide 4 to 150 weight ppm
of platinum on the same basis. The catalyst may be added as a single species or as
a mixture of two or more different species.
(D) The Carrier Fluid
[0038] The silicone elastomers may be contained in an optional carrier fluid (D). Although
it is not required, typically the carrier fluid may be the same as the solvent used
for conducting the hydrosilylation reaction as described above. Suitable carrier fluids
include silicones, both linear and cyclic, organic oils, organic solvents and mixtures
of these. Specific examples of solvents may be found in
U.S. Patent No. 6,200,581.
[0039] Typically, the carrier fluid is a low viscosity silicone or a volatile methyl siloxane
or a volatile ethyl siloxane or a volatile methyl ethyl siloxane having a viscosity
at 25°C in the range of 1 to 1,000 mm
2/s such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane,
dodecamethylcyclohexasiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane,
tetradecamethylhexasiloxane, hexadeamethylheptasiloxane, heptamethyl-3-{(trimethylsilyl)oxy)}trsiloxane,
hexamethyl-3,3,bis{(trimethylsilyl)oxy}trisiloxane pentamethyl{(trimethylsilyl)oxy}cyclotrisiloxane
as well as polydimethylsiloxanes, polyethylsiloxanes, polymethylethylsiloxanes, polymethylphenylsiloxanes,
polydiphenylsiloxanes.
[0040] Organic solvents may be exemplified by, but not limited to, aromatic hydrocarbons,
aliphatic hydrocarbons, alcohols, aldehydes, ketones, amines, esters, ethers, glycols,
glycol ethers, alkylhalides and aromatic halides. Hydrocarbons including isododecane,
isohexadecane, Isopar L (C11-C13 ), Isopar H(C11-C12), hydrogentated polydecen. Ethers
and esters including isodecyl neopentanoate, neopentylglycol heptanoate, glycol distearate,
dicaprylyl carbonate, diethylhexyl carbonate, propylene glycol n butyl ether, ethyl-3
ethoxypropionate, propylene glycol methyl ether acetate, tridecyl neopentanoate, propylene
glycol methylether acetate (PGMEA), propylene glycol methylether (PGME). octyldodecyl
neopentanoate, diisobutyl adipate, diisopropyl adipate, propylene glycol dicaprylate
dicaprate, and octyl palmitate. Additional organic carrier fluids suitable as a stand
alone compound or as an ingredient to the carrier fluid include fats, oils, fatty
acids, and fatty alcohols.
[0041] The amount of carrier fluid is such that there is 0 to 98 weight percent, alternatively
0.5 to 90 weight percent, alternatively 5 to 80 weight percent, of carrier fluid in
composition containing (A) and (B) and (D), where the sum of (A), (B), and (D) is
100 weight percent.
E) Personal or Healthcare Active
[0042] Component E) is active selected from any personal or health care active. As used
herein, a "personal care active" means any compound or mixtures of compounds that
are known in the art as additives in the personal care formulations that are typically
added for the purpose of treating hair or skin to provide a cosmetic and/or aesthetic
benefit. A "healthcare active" means any compound or mixtures of compounds that are
known in the art to provided a pharmaceutical or medical benefit. Thus, "healthcare
active" include materials considered as an
active ingredient or
active drug ingredient as generally used and defined by the United States Department of Health & Human Services
Food and Drug Administration, contained in Title 21, Chapter I, of the Code of Federal
Regulations, Parts 200-299 and Parts 300-499.
[0043] Thus,
active ingredient can include any component that is intended to furnish pharmacological activity or
other direct effect in the diagnosis, cure, mitigation, treatment, or prevention of
disease, or to affect the structure or any function of the body of a human or other
animals. The phrase can include those components that may undergo chemical change
in the manufacture of drug products and be present in drug products in a modified
form intended to furnish the specified activity or effect.
[0044] Some representative examples
of active ingredients include; drugs, vitamins, minerals; hormones; topical antimicrobial agents such as
antibiotic
active ingredients, antifungal
active ingredients for the treatment of athlete's foot, jock itch, or ringworm, and acne
active ingredients; astringent
active ingredients; deodorant
active ingredients; wart remover
active ingredients; corn and callus remover
active ingredients; pediculicide
active ingredients for the treatment of head, pubic (crab), and body lice;
active ingredients for the control of dandruff, seborrheic dermatitis, or psoriasis; and sunburn prevention
and treatment agents.
[0045] Useful
active ingredients for use in processes according to the invention include vitamins and its derivatives,
including "pro-vitamins". Vitamins useful herein include, but are not limited to,
Vitamin A
1, retinol, C
2-C
18 esters of retinol, vitamin E, tocopherol, esters of vitamin E, and mixtures thereof.
Retinol includes trans-retinol, 1, 3-cis-retiriol, 11-cis-retinol, 9-cis-retinol,
and 3,4-didehydro-retinol, Vitamin C and its derivatives, Vitamin B
1, Vitamin B
2, Pro Vitamin B5, panthenol, Vitamin B
6, Vitamin B
12, niacin, folic acid, biotin, and pantothenic acid. Other suitable vitamins and the
INCI names for the vitamins considered included herein are ascorbyl dipalmitate, ascorbyl
methylsilanol pectinate, ascorbyl palmitate, ascorbyl stearate, ascorbyl glucocide,
sodium ascorbyl phosphate, sodium ascorbate, disodium ascorbyl sulfate, potassium
(ascorbyl / tocopheryl) phosphate.
[0046] RETINOL, it should be noted, is an International Nomenclature Cosmetic Ingredient
Name (INCI) designated by The Cosmetic, Toiletry, and Fragrance Association (CTFA),
Washington DC, for vitamin A. Other suitable vitamins and the INCI names for the vitamins
considered included herein are RETINYL ACETATE, RETINYL PALMITATE, RETINYL PROPIONATE,
α-TOCOPHEROL, TOCOPHERSOLAN, TOCOPHERYL ACETATE, TOCOPHERYL LINOLEATE, TOCOPHERYL
NICOTINATE, and TOCOPHERYL SUCCINATE.
[0047] Some examples of commercially available products suitable for use herein are Vitamin
A Acetate and Vitamin C, both products of Fluka Chemie AG, Buchs, Switzerland; COVI-OX
T-50, a vitamin E product of Henkel Corporation, La Grange, Illinois; COVI-OX T-70,
another vitamin E product of Henkel Corporation, La Grange, Illinois; and vitamin
E Acetate, a product of Roche Vitamins & Fine Chemicals, Nutley, New Jersey.
[0048] The
active ingredient used in processes according to the invention can be an
active drug ingredient. Representative examples of some suitable
active drug ingredients which can be used are hydrocortisone, ketoprofen, timolol, pilocarpine, adriamycin,
mitomycin C, morphine, hydromorphone, diltiazem, theophylline, doxorubicin, daunorubicin,
heparin, penicillin G, carbenicillin, cephalothin, cefoxitin, cefotaxime, 5-fluorouracil,
cytarabine, 6-azauridine, 6-thioguanine, vinblastine, vincristine, bleomycin sulfate,
aurothioglucose, suramin, mebendazole, clonidine, scopolamine, propranolol, phenylpropanolamine
hydrochloride, ouabain, atropine, haloperidol, isosorbide, nitroglycerin, ibuprofen,
ubiquinones, indomethacin, prostaglandins, naproxen, salbutamol, guanabenz, labetalol,
pheniramine, metrifonate, and steroids.
[0049] Considered to be included herein as
active drug ingredients for purposes of the present invention are antiacne agents such as benzoyl peroxide
and tretinoin; antibacterial agents such as chlorohexadiene gluconate; antifungal
agents such as miconazole nitrate; anti-inflammatory agents; corticosteroidal drugs;
non-steroidal anti-inflammatory agents such as diclofenac; antipsoriasis agents such
as clobetasol propionate; anesthetic agents such as lidocaine; antipruritic agents;
antidermatitis agents; and agents generally considered barrier films.
[0050] The active component E) of the present invention can be a protein, such as an enzyme.
The internal inclusion of enzymes in the silicone elastomer gel have advantages to
prevent enzymes from deactivating and maintain bioactive effects of enzymes for longer
time. Enzymes include, but are not limited to, commercially available types, improved
types, recombinant types, wild types, variants not found in nature, and mixtures thereof.
For example, suitable enzymes include hydrolases, cutinases, oxidases, transferases,
reductases, hemicellulases, esterases, isomerases, pectinases, lactases, peroxidases,
laccases, catalases, and mixtures thereof. Hydrolases include, but are not limited
to, proteases (bacterial, fungal, acid, neutral or alkaline), amylases (alpha or beta),
lipases, mannanases, cellulases, collagenases, lisozymes, superoxide dismutase, catalase,
and mixtures thereof.
Said protease include, but are not limited to, trypsin, chymotrypsin, pepsin, pancreatin
and other mammalian enzymes; papain, bromelain and other botanical enzymes; subtilisin,
epidermin, nisin, naringinase (L-rhammnosidase), urokinase and other bacterial enzymes.
Said lipases include, but are not limited to, triacyl-glycerol lipases, monoacyl-glycerol
lipases, lipoprotein lipases, e.g. steapsin, erepsin, pepsin, other mammalian, botanical,
bacterial lipases and purified ones. Natural papain is preferred as said enzyme. Further,
stimulating hormones, e.g. insulin, can be used together with these enzymes to boost
the effectiveness of them.
[0051] Component E) may also be a sunscreen agent. The sunscreen agent can be selected from
any sunscreen agent known in the art to protect skin from the harmful effects of exposure
to sunlight. The sunscreen compound is typically chosen from an organic compound,
an inorganic compound, or mixtures thereof that absorbs ultraviolet (UV) light. Thus,
representative non limiting examples that can be used as the sunscreen agent include;
Aminobenzoic Acid, Cinoxate, Diethanolamine Methoxycinnamate, Digalloyl Trioleate,
Dioxybenzone, Ethyl 4-[bis(Hydroxypropyl)] Aminobenzoate, Glyceryl Aminobenzoate,
Homosalate, Lawsone with Dihydroxyacetone, Menthyl Anthranilate, Octocrylene, Octyl
Methoxycinnamate, Octyl Salicylate, Oxybenzone, Padimate O, Phenylbenzimidazole Sulfonic
Acid, Red Petrolatum, Sulisobenzone, Titanium Dioxide, and Trolamine Salicylate, cetaminosalol,
Allatoin PABA, Benzalphthalide, Benzophenone, Benzophenone 1-12, 3-Benzylidene Camphor,
Benzylidenecamphor Hydrolyzed Collagen Sulfonamide, Benzylidene Camphor Sulfonic Acid,
Benzyl Salicylate, Bornelone, Bumetriozole, Butyl Methoxydibenzoylmethane, Butyl PABA,
Ceria/Silica, Ceria/Silica Talc, Cinoxate, DEA-Methoxycinnamate, Dibenzoxazol Naphthalene,
Di-t-Butyl Hydroxybenzylidene Camphor, Digalloyl Trioleate, Diisopropyl Methyl Cinnamate,
Dimethyl PABA Ethyl Cetearyldimonium Tosylate, Dioctyl Butamido Triazone, Diphenyl
Carbomethoxy Acetoxy Naphthopyran, Disodium Bisethylphenyl Tiamminotriazine Stilbenedisulfonate,
Disodium Distyrylbiphenyl Triaminotriazine Stilbenedisulfonate, Disodium Distyrylbiphenyl
Disulfonate, Drometrizole, Drometrizole Trisiloxane, Ethyl Dihydroxypropyl PABA, Ethyl
Diisopropylcinnamate, Ethyl Methoxycinnamate, Ethyl PABA, Ethyl Urocanate, Etrocrylene
Ferulic Acid, Glyceryl Octanoate Dimethoxycinnamate, Glyceryl PABA, Glycol Salicylate,
Homosalate, Isoamyl p-Methoxycinnamate, Isopropylbenzyl Salicylate, Isopropyl Dibenzolylmethane,
Isopropyl Methoxycinnamate, Menthyl Anthranilate, Menthyl Salicylate, 4-Methylbenzylidene,
Camphor, Octocrylene, Octrizole, Octyl Dimethyl PABA, Octyl Methoxycinnamate, Octyl
Salicylate, Octyl Triazone, PABA, PEG-25 PABA, Pentyl Dimethyl PABA, Phenylbenzimidazole
Sulfonic Acid, Polyacrylamidomethyl Benzylidene Camphor, Potassium Methoxycinnamate,
Potassium Phenylbenzimidazole Sulfonate, Red Petrolatum, Sodium Phenylbenzimidazole
Sulfonate, Sodium Urocanate, TEA-Phenylbenzimidazole Sulfonate, TEA-Salicylate, Terephthalylidene
Dicamphor Sulfonic Acid, Titanium Dioxide, Zinc Dioxide, Serium Dioxide, TriPABA Panthenol,
Urocanic Acid, and VA/Crotonates/Methacryloxybenzophenone-1 Copolymer.
[0052] The sunscreen agent can be a single one or combination of more than one. Alternatively,
the sunscreen agent is a cinnamate based organic compound, or alternatively, the sunscreen
agent is octyl methoxycinnamate, such as Uvinul® MC 80 an ester of para-methoxycinnamic
acid and 2-ethylhexanol.
[0053] Component E) may also be a fragrance or perfume. The perfume can be any perfume or
fragrance active ingredient commonly used in the perfume industry. These compositions
typically belong to a variety of chemical classes, as varied as alcohols, aldehydes,
ketones, esters, ethers, acetates, nitrites, terpenic hydrocarbons, heterocyclic nitrogen
or sulfur containing compounds, as well as essential oils of natural or synthetic
origin. Many of these perfume ingredients are described in detail in standard textbook
references such as
Perfume and Flavour Chemicals, 1969, S. Arctander, Montclair, New Jersey.
[0054] Fragrances may be exemplified by, but not limited to, perfume ketones and perfume
aldehydes. Illustrative of the perfume ketones are buccoxime; iso jasmone; methyl
beta naphthyl ketone; musk indanone; tonalid/musk plus; Alpha-Damascone, Beta-Damascone,
Delta-Damascone, Iso-Damascone, Damascenone, Damarose, Methyl-Dihydrojasmonate, Menthone,
Carvone, Camphor, Fenchone, Alpha-lonone, Beta-lonone, Gamma-Methyl so-called lonone,
Fleuramone, Dihydrojasmone, Cis-Jasmone, Iso-E-Super, Methyl-Cedrenyl-ketone or Methyl-
Cedrylone, Acetophenone, Methyl-Acetophenone, Para-MethoxyAcetophenone, Methyl-Beta-Naphtyl-Ketone,
Benzyl-Acetone, Benzophenone, Para-Hydroxy-Phenyl-Butanone, Celery Ketone or Livescone,
6-Isopropyldecahydro-2-naphtone, Dimethyl-Octenone, Freskomenthe, 4-(1-Ethoxyvinyl)-3,3,5,5,-tetramethyl-Cyclohexanone,
Methyl-Heptenone, 2-(2-(4-Methyl-3-cyclohexen-1-yl)propyl)-cyclopentanone, 1-(p-Menthen-6(2)-yl)-1-propanone,
4-(4-Hydroxy-3-methoxyphenyl)-2-butanone, 2-Acetyl-3,3-Dimethyl-Norbomane, 6,7-Dihydro-1,1,2,3,3-Pentamethyl-4(5H)-Indanone,
4-Damascol, Dulcinyl or Cassione, Gelsone, Hexalon, Isocyclemone E, Methyl Cyclocitrone,
Methyl-Lavender-Ketone, Orivon, Para-tertiary-Butyl-Cyclohexanone, Verdone, Delphone,
Muscone, Neobutenone, Plicatone, Veloutone, 2,4,4,7-Tetramethyl-oct-6-en-3-one, and
Tetrameran.
[0055] More preferably, the perfume ketones are selected for its odor character from Alpha
Damascone, Delta Damascone, Iso Damascone, Carvone, Gamma-Methyl-lonone, Iso-E-Super,
2,4,4,7-Tetramethyl-oct-6-en-3-one, Benzyl Acetone, Beta Damascone, Damascenone, methyl
dihydrojasmonate, methyl cedrylone, and mixtures thereof.
[0056] Preferably, the perfume aldehyde is selected for its odor character from adoxal;
anisic aldehyde; cymal; ethyl vanillin; florhydral; helional; heliotropin; hydroxycitronellal;
koavone; lauric aldehyde; lyral; methyl nonyl acetaldehyde; P. T. bucinal; phenyl
acetaldehyde; undecylenic aldehyde; vanillin; 2,6,10-trimethyl-9-undecenal, 3-dodecen-1-al,
alpha-n-amyl cinnamic aldehyde, 4-methoxybenzaldehyde, benzaldehyde, 3-(4-tert butylphenyl)-propanal,
2-methyl-3-(para-methoxyphenyl propanal, 2-methyl-4-(2,6,6-trimethyl-2(1)-cyclohexen-1-yl)
butanal, 3-phenyl-2-propenal, cis-/trans-3,7-dimethyl-2,6-octadien-1-al, 3,7-dimethyl-6-octen-1-al,
[(3,7-dimethyl-6-octenyl)oxy] acetaldehyde, 4-isopropylbenzyaldehyde, 1,2,3,4,5,6,7,8-octahydro-8,8-dimethyl-2-naphthaldehyde,
2,4-dimethyl-3-cyclohexen-1-carboxaldehyde, 2-methyl-3-(isopropylphenyl)propanal,
1-decanal; decyl aldehyde, 2,6-dimethyl-5-heptenal, 4-(tricyclo[52.1.0(2,6)]-decylidene-8)-butanal,
octahydro-4,7-methano-1H- indenecarboxaldehyde, 3-ethoxy-4-hydroxy benzaldehyde, para-ethyl-alpha,
alpha-dimethyl hydrocinnamaldehyde, alpha-methyl-3,4-(methylenedioxy)-hydrocinnamaldehyde,
3,4-methylenedioxybenzaldehyde, alpha-n-hexyl cinnamic aldehyde, m-cymene-7-carboxaldehyde,
alpha-methyl phenyl acetaldehyde, 7-hydroxy-3,7-dimethyl octanal, Undecenal, 2,4,6-trimethyl-3-cyclohexene-1-carboxaldehyde,
4-(3)(4-methyl-3-pentenyl)-3-cyclohexen-carboxaldehyde, 1-dodecanal, 2,4-dimethyl
cyclohexene-3-carboxaldehyde, 4-(4-hydroxy-4-methyl pentyl)-3-cylohexene-1-carboxaldehyde,
7-methoxy-3,7-dimethyloctan-1-al, 2-methyl undecanal, 2-methyl decanal, 1-nonanal,
1-octanal, 2,6,10-trimethyl-5,9-undecadienal, 2-methyl-3-(4-tertbutyl)propanal, dihydrocinnamic
aldehyde, 1-methyl-4-(4-methyl-3-pentenyl)-3-cyclohexene-1-carbox aldehyde, 5 or 6
methoxyl 0 hexahydro-4,7-methanoindan-1 or 2-carboxaldehyde, 3,7-dimethyloctan-1-al,
1 -undecanal, 10-undecen-1-al, 4-hydroxy-3-methoxy benzaldehyde, 1-methyl-3-(4-methylpentyl)-3-cyclhexenecarboxaldehyde,
7-hydroxy-3,7-dimethyl-octanal, trans-4-decenal, 2,6-nonadienal, paratolylacetaldehyde;
4-methylphenylacetaldehyde, 2-methyl-4-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2-butena
1, ortho-methoxycinnamic aldehyde, 3,5,6-trimethyl-3-cyclohexene carboxaldehyde, 3,7-dimethyl-2-methylene-6-octenal,
phenoxyacetaldehyde, 5,9-dimethyl-4,8-decadienal, peony aldehyde (6,10-dimethyl-3-oxa-5,9-undecadien-1-al),
hexahydro-4,7-methanoindan-1-carboxaldehyde, 2-methyl
octanal, alpha-methyl-4-(1-methyl ethyl) benzene acetaldehyde, 6,6-dimethyl-2-norpinene-2-propionaldehyde,
para methyl phenoxy acetaldehyde, 2-methyl-3-phenyl-2-propen-1-al, 3,5,5-trimethyl
hexanal, Hexahydro-8,8-dimethyl-2-naphthaldehyde, 3-propyl-bicyclo[2.2.1]-hept-5-ene-2-carbaldehyde,
9-decenal, 3-methyl-5-phenyl-1-pentanal, methylnonyl acetaldehyde, hexanal, trans-2-hexenal,
1-p-menthene-q-carboxaldehyde and mixtures thereof.
[0057] More preferred aldehydes are selected for their odor character from 1-decanal, benzaldehyde,
florhydral, 2,4-dimethyl-3-cyclohexen-1-carboxaldehyde; cis/trans-3,7-dimethyl-2,6-octadien-1-al;
heliotropin; 2,4,6-trimethyl-3-cyclohexene-1-carboxaldehyde; 2,6-nonadienal; alpha-n-amyl
cinnamic aldehyde, alpha-n-hexyl cinnamic aldehyde, P.T. Bucinal, lyral, cymal, methyl
nonyl acetaldehyde, hexanal, trans-2-hexenal, and mixture thereof.
[0058] In the above list of perfume ingredients, some are commercial names conventionally
known to one skilled in the art, and also includes isomers. Such isomers are also
suitable for use in the present invention.
[0059] Component E) may also be one or more plant extract. Examples of these components
are as follows: Ashitaba extract, avocado extract, hydrangea extract, Althea extract,
Arnica extract, aloe extract, apricot extract, apricot kernel extract, Ginkgo Biloba
extract, fennel extract, turmeric [Curcuma] extract, oolong tea extract, rose fruit
extract, Echinacea extract, Scutellaria root extract, Phellodendro bark extract, Japanese
Coptis extract, Barley extract, Hyperium extract, White Nettle extract, Watercress
extract, Orange extract, Dehydrated saltwater, seaweed extract, hydrolyzed elastin,
hydrolyzed wheat powder, hydrolyzed silk, Chamomile extract, Carrot extract, Artemisia
extract, Glycyrrhiza extract, hibiscustea extract, Pyracantha Fortuneana Fruit extract,
Kiwi extract, Cinchona extract, cucumber extract, guanocine, Gardenia extract, Sasa
Albo-marginata extract, Sophora root extract, Walnut extract, Grapefruit extract,
Clematis extract, Chlorella extract, mulberry extract, Gentiana extract, black tea
extract, yeast extract, burdock extract, rice bran ferment extract, rice germ oil,
comfrey extract, collagen, cowberry extract, Gardenia extract, Asiasarum Root extract,
Family of Bupleurum extract, umbilical cord extract, Salvia extract, Saponaria extract,
Bamboo extract, Crataegus fruit extract, Zanthoxylum fruit extract, shiitake extract,
Rehmannia root extract, gromwell extract, Perilla extract, linden extract, Filipendula
extract, peony extract, Calamus Root extract, white birch extract, Horsetail extract,
Hedera Helix (Ivy) extract, hawthorn extract, Sambucus nigra extract, Achillea millefolium
extract, Mentha piperita extract, sage extract, mallow extract, Cnidium officinale
Root extract, Japanese green gentian extract, soybean extract, jujube extract, thyme
extract, tea extract, clove extract, Gramineae imperata cyrillo extract, Citrus unshiu
peel extract Japanese Angellica Root extract, Calendula extract, Peach Kernel extract,
Bitter orange peel extract, Houttuyna cordata extract, tomato extract, natto extract,
Ginseng extract, Green tea extract (camelliea sinesis), garlic extract, wild rose
extract, hibiscus extract, Ophiopogon tuber extarct, Nelumbo nucifera extract, parsley
extract, honey, hamamelis extract, Parietaria extract, Isodonis herba extract, bisabolol
extract, Loquat extract, coltsfoot extract, butterbur extract, Porid cocos wolf extract,
extract of butcher's broom, grape extract, propolis extract, luffa extract, safflower
extract, peppermintextract, linden tree extract, Paeonia extract, hop extract, pine
tree extract, horse chestnut extract, Mizu-bashou [Lysichiton camtschatcese] extract,
Mukurossi peel extract, Melissa extract, peach extract, cornflower extract, eucalyptus
extract, saxifrage extract, citron extract, coix extract, mugwort extract, lavender
extract, apple extract, lettuce extract, lemon extract, Chinese milk vetch extract,
rose extract, rosemary extract, Roman Chamomile extract, and royal jelly extract.
[0060] The amount of component E) present in the silicone gel composition may vary, but
typically range as follows;
0.05 to 50 wt%, alternatively 1 to 25 wt %, or alternatively 1 to 10 wt%,
based on the amount by weight of silicone elastomer gel present in the composition,
that is total weight of components A), B), C) and D) in the silicone gel composition.
[0061] The active, component E), may be added to the silicone gel composition either during
the making of the silicone elastomer (pre-load method), or added after the formation
of the silicone elastomer gel (post load method).
[0062] The pre-load method involves;
- I) reacting;
a) an organohydrogencyclosiloxane having at least two SiH units on a siloxane ring,
B) a compound or mixture of compounds having at least two aliphatic unsaturated hydrocarbon
groups in its molecules,
C) a hydrosilylation catalyst,
to form
- A) an organohydrogensiloxane having at least two SiH containing cyclosiloxane rings
in its molecule,
wherein the molar ratio of the SiH units of component a) to the aliphatic unsaturated
hydrocarbon groups of component B) ranges from 2/1 to 8/1,
- II) reacting;
- A) the organohydrogensiloxane having at least two SiH containing cyclosiloxane rings
in its molecule, with additional quantities of
- B) the compound containing at least two aliphatic unsaturated hydrocarbon groups in
its molecules,
- C) the hydrosilylation catalyst,
in the presence of
D) an optional carrier fluid, and
E) a personal care or healthcare active,
to form the silicone elastomer gel.
[0063] The post-load method involves;
- I) reacting;
a) an organohydrogencyclosiloxane having at least two SiH units on a siloxane ring,
B) a compound or mixture of compounds having at least two aliphatic unsaturated groups
in its molecules,
C) a hydrosilylation catalyst
to form
- A) an organohydrogensiloxane having at least two SiH containing cyclosiloxane rings
in its molecule,
wherein the molar ratio of the SiH units of component a) to the aliphatic unsaturated
groups of component B) ranges from 2/1 to 8/1,
- II) further reacting;
- A) the organohydrogensiloxane having at least two SiH containing cyclosiloxane rings
in its molecule, with additional quantities of
- B) the compound containing at least two aliphatic unsaturated groups in its molecules,
- C) the hydrosilylation catalyst,
in the presence of
D) an optional carrier fluid
to form a silicone elastomer gel,
- III) admixing
E) a personal care or healthcare active with the silicone elastomer gel
to form the silicone elastomer gel containing active.
The Silicone Elastomer
[0064] The silicone elastomers of the present invention are obtainable as hydrosilylation
reaction products of components A), B), and C). The term "hydrosilylation" means the
addition of an organosilicon compound containing silicon-bonded hydrogen, (such as
component A) to a compound containing aliphatic unsaturation (such as component B),
in the presence of a catalyst (such as component C). Hydrosilylation reactions are
known in the art, and any such known methods or techniques may be used to effect the
hydrosilylation reaction of components A), B), and C) to prepare the silicone elastomers
of the present invention.
[0065] The hydrosilylation reaction may be conducted in the presence of a solvent, and the
solvent subsequently removed by known techniques. Alternatively, the hydrosilylation
may be conducted in a solvent, where the solvent is the same as the carrier fluid
described as optional component D).
[0066] Alternatively, the silicone elastomers may be prepared by a process comprising:
- I) reacting;
a) an organohydrogencyclosiloxane having at least two SiH units on a siloxane ring,
B) a compound or mixture of compounds having at least two aliphatic unsaturated hydrocarbon
groups in its molecules,
C) a hydrosilylation catalyst
to form
- A) an organohydrogensiloxane having at least two SiH containing cyclosiloxane rings
in its molecule,
wherein the molar ratio of the SiH units of component a) to the aliphatic unsaturated
groups of component B) ranges from 2/1 to 8/1, alternatively from 2/1 to 6/1, or alternatively
from 3/1 to 4/1,
- II) further reacting;
- A) the organohydrogensiloxane having at least two SiH containing cyclosiloxane rings
in its molecule, with additional quantities of
- B) the compound containing at least two aliphatic unsaturated groups in its molecules,
- C) the hydrosilylation catalyst.
to form a silicone elastomer.
[0067] Components a, A), B), C) are the same as those described above. Also, the reaction
may be conducted under similar conditions as described above. In aforementioned step
II) the molar ratio of the SiH units of component A) to the aliphatic unsaturated
groups of component B) ranges from 10/1 to 1/10, altematively from 5/1 to 1/5, or
alternatively from 4/1 to 1/4.
Gelled compositions containing the Silicone Elastomer
[0068] The silicone elastomers can be added to a carrier fluid (as described above as component
D) to form gelled compositions, or alternatively be prepared first in a separate reaction
and then added to the carrier fluid to obtain a gel. The gelled compositions of the
present invention may be characterized by their hardness or firmness. Useful tests
to characterize the gels are those recommended by the
Gelatin Manufacturers Institute of America such as the use of a "Texture Analyzer" (model TA.XT2, Stable Micro Systems, Inc.,
Godalming, England). The gel sample is subject to a compression test with the Texture
Analyzer having a probe with a 5.0 kg load cell. The probe approaches the surface
of the gel at a speed of 0.5 mm/s and continues compression into the gel to a distance
of 5.0 mm, then holds for 1 second before retreating. The Texture Analyzer detects
the resistance force the probe experiences during the compression test. The force
exhibited by the load cell is plotted as a function of time.
[0069] The hardness of the silicone elastomers, gels and elastomer blends (SEBs) for purposes
of this invention is defined as the resistance force detected by the probe of the
"Texture Analyzer" during the compression test. Two data may used to characterize
hardness: Force 1, the force at the maximum compression point (i.e. the 5.0 mm compression
point into the gel surface), and Area F-T: the area-force integration during the 1
second hold at the maximum compression point. The average of a total of 5 tests are
typically performed for each gel.
[0070] The value obtained for Force 1 is converted into Newton (N), by dividing the gram
force value by 101.97 (i.e. 1 Newton equals 101.97 g force based on the size of the
probe used in this instrument). The second property reported by Texture Analyzer measurement
is Area F-T 1:2, in g force·s. This is the area integration of the force vs. test
time cure. This property is indicative of a gel network since it indicates ability
to sustain resistance to the compression force, which is relevant to elastomers and
gels. The value is reported in g force·s, and is converted to Newton·s in SI unit
by dividing the value in g force·s by 101.97.
[0071] The silicone gels of the present invention has a compression hardness of at least
200 Newton m
2, alternatively 400 Newton m
2, or alternatively 600 Newton / m
2.
Gel Paste compositions containing the Silicone Elastomer
[0072] The gelled compositions of the present invention can be used to prepare gel paste
or gel blend compositions containing actives by;
- I) shearing the silicone elastomer gel, as described above,
- II) combining the sheared silicone elastomer gel with additional quantities of
D) the carrier fluid, as described above, and optionally
E) a personal or health care active
to form a gel paste or blend composition.
[0073] The silicone elastomer gel compositions of the present invention blends may be considered
as discrete crosslinked silicone elastomer gel particles dispersed in carrier fluids.
Thus, the silicone elastomer compositions are effective rheological thickeners for
lower molecular weight silicone fluids. As such they can be used to prepare useful
gel blend compositions, such as "paste" compositions.
[0074] To make such silicone elastomer blends, the aforementioned silicone elastomer gels
of known initial elastomer content (IEC) are sheared to obtain small particle size
and further diluted to a final elastomer content (FEC). "Shearing", as used herein
refers to any shear mixing process, such as obtained from homogenizing, sonalating,
or any other mixing processes known in the art as shear mixing. The shear mixing of
the silicone elastomer gel composition results in a composition having reduced particle
size. The subsequent composition having reduced particle size is then further combined
with D) the carrier fluid. The carrier fluid may be any carrier fluid as described
above, but typically is a volatile methyl siloxane, such as D5. The technique for
combining the D) the carrier fluid with the silicone elastomer composition having
reduced particle size is not critical, and typically involves simple stirring or mixing.
The resulting compositions may be considered as a paste, having a viscosity greater
than 100,000 cP (mPa·s).
Examples
[0075] These examples are intended to illustrate the invention to one of ordinary skill
in the art and are should not be interpreted as limiting the scope of the invention
set forth in the claims.
Materials description
[0076] The following materials were used in these examples.
Organohydrogensiloxanes
[0077] MeH CYCLICS = methylhydrogen cyclosiloxanes (MeH cyclics) having the formula
[(CH
3)HSiO]
x
where the average value of x is 4.4.
[0078] MeH LINEAR = an organohydrogenpolysiloxane have the average formula
MD
94D'
6M
Siloxane polymers containing unsaturated groups
[0079] VINYL SILOXANE #1 = a dimethylvinylsiloxy-terminated dimethylpolysiloxane of the
general formula (CH
2=CH)(CH
3)
2SiO[(CH
3)
2SiO]
dpSi(CH
3)
2(CH=CH
2), where the average degree of polymerization (dp) was 8 and having a viscosity of
4 mm
2/s at 25°C.
[0080] VINYL SILOXANE #2 = a dimethylvinylsiloxy-terminated
dimethylpolysiloxane of the general formula
(CH
2=CH)(CH
3)
2SiO[(CH
3)
2SiO]
dpSi(CH
3)
2(CH=CH
2),
where the average degree of polymerization (dp) was 130 and having a viscosity of
325 mm
2/s at 25°C.
VINYL SILOXANE #3 = [(CH2=CH)(CH3)2SiO[(CH3)2SiO]30]4Si
VINYL SILOXANE #4 = tetramethyltetravinylcyclotetrasiloxane [(CH2=CH)(CH3)SiO]4
VINYL SILOXANE #5 = a dimethylvinylsiloxy-terminated dimethylpolysiloxane of the general
formula (CH2=CH)(CH3)2SiO[(CH3)2SiO]dpSi(CH3)2(CH=CH2), where the average degree of polymerization (dp) was 27 and having a viscosity of
25 mm2/s at 25°C.
VINYL SILOXANE #6 = a dimethylhexenylsiloxy-terminated dimethylpolysiloxane of the
general formula (CH2=CH(CH2)4)(CH3)2SiO[(CH3)2SiO]dpSi(CH3)2((CH2)4(CH2=CH)), where the average degree of polymerization (dp) was 37 and a viscosity of 40
mm2/s at 25°C.
VINYL SILOXANE #7 = a dimethylhexenylsiloxy-terminated dimethylpolysiloxane of the
general formula (CH2=CH(CH2)4)(CH3)2SiO[(CH3)2SiO]dpSi(CH3)2((CH2)4(CH2=CH)), where the average degree of polymerization (dp) was 100 and a viscosity of
170 mm2 /s at 25°C.
VINYL SILOXANE #8 = a dimetlaylhexenylsiloxy-terminated dimethylpolysiloxane of the
general formula (CH2=CH(CH2)4)(CH3)2SiO[(CH3)2SiO]dpSi(CH3)2((CH2)4(CH2=CH)), where the average degree of polymerization (dp) was 200 and a viscosity of
730 mm2/s at 25°C.
VINYL SILOXANE #9 = a dimethylvinylsiloxy-terminated dimethylpolysiloxane of the general
formula (CH2=CH)(CH3)2SiO[(CH3)2SiO]dpSi(CH3)2(CH=CH2), where the average degree of polymerization (dp) was 27.
VINYL SILOXANE #10 = a dimethylvinylsiloxy-terminated dimethylpolysiloxane of the
general formula (CH2=CH)(CH3)2SiO[(CH3)2SiO]dpSi(CH3)2(CH=CH2), where the average degree of polymerization (dp) was 430.
Hydrosilylation catalyst
[0081] PT CATALYST = SLY-OFF 4000 (Dow Corning Corporation, Midland MI) Pt catalyst used
as provided containing 0.52 weight % Pt.
Carrier Fluids
[0082] D5 = decamethylcyclopentasiloxane or D5 cyclics, DC245 (Dow Corning Corporation,
Midland MI) used as provided.
IDNP = isodecyl neopentanoate obtained from ISP (International Specialty Products
Co) under the trade name of CERAPHYL SLK.
IDD = isododecane
Stabilizer = Vitamin A palmitate (VAP) and butylated hydroxytoluene (BHT)
Methods of Measuring- Viscosity of Silicone Elastomer Blends (SEBs)
[0083] The Brookfield Helipath™ Stand, when used with a suitable Brookfield Viscometer fitted
with a special T-bar type spindle, will permit viscosity/consistency measurements
in centipoise values for materials having characteristics similar to paste, putty,
cream, gelatin, or wax.
[0084] The viscosity of silicone elastomer blends was determined using a Brookfield Model
RVD-II+ Viscometer with Helipath stand (Brookfield Model D) and T-Bar spindles (Brookfield
Helipath Spindle Set). All were purchased from Brookfield Engineering Laboratories,
Inc. (11 Commerce Boulevard Middleboro, Massachusetts, USA).
[0085] A sample size of 100g in a 4 oz. (118.3 ml) round jar was required. The following
preparation procedure was used before measurement: the sample was de-aired first via
centrifuge, then vacuum de-aired for two hours. After de-airing, the sample was conditioned
for a minimum of 4 hours @ 25° C. The sample was positioned with T-bar spindle at
center. The reading was taken according to the typical procedure for Helipath spindle.
[0086] In general, spindle 93 (T-bar spindle C) is used for the less viscous sample, spindle
95 (T-bar spindle E) for the more viscous samples. The standard setting for rpm was
2.5. The spindle speed is maintained at constant 2.5 rpm and spindle was varied to
handle samples with significant viscosities.
Measurement of Silicone Elastomer Gel Hardness
[0088] For silicone gels and elastomer blends, a ½ inch (1.27 cm) diameter cylindrical probe
made of DELRIN acetal resin (Dupont) was used for the measurement. The gel sample
is subject to the compression test using the probe with the following test cycle:
the probe approaches the surface of the gel at a speed of 0.5 mm/s and continues compression
into the gel to a distance of 5.0 mm, then holds for 1 second before retreating. The
Texture Analyzer has a 5.0 Kg load cell to detect the resistance force the probe experiences
during the compression test. The force exhibited by the load cell is plotted as a
function of time.
The hardness of the silicone elastomers, gels and elastomer blends (SEBs) is defined
as the resistance force detected by the probe during the compression test. Two data
are used for the hardness value: Force 1: the force at the maximum compression point
(i.e. the 5.0 mm compression point into the gel surface), and Area F-T: the area-force
integration during the 1 second hold at the maximum compression point. A total of
5 tests were performed for each gel and the average of the five tests is reported.
[0089] Texture Analyzer used for gel hardness measurement is force in gram, as detected
by the transducer. Two values are reported for gel hardness: Force 1, the force in
gram registered when the probe reached its pre-programmed full indentation (or compression)
in gel sample. The unit for Force 1 reading is gram force.
[0090] The value obtained for Force 1 is converted into Newton (N), by dividing the gram
force value by 101.97. (i.e. 1 Newton equals 101.97 g force based on the size of the
probe used in this instrument). For instance, a value of 6327 g force converts to
62.0 N.
[0091] The second property reported by Texture Analyzer measurement is Area F-T 1:2, in
g force·sec. This is the area integration of the force vs. test time cure. This is
an indicative property of a gel network as it indicates it ability to sustain resistance
to the compression force, which is relevant to elastomers and gels.
[0092] The value is reported in g force·s, and is converted to Newton·s in SI unit by dividing
the value in g force·s by 101.97. For instance, a value of 33,947 g force·s is 332.9
N·s in SI units.
Example 1 (reference)
Preparation of an organohydrogensiloxane having at least two SiH containing cyclosiloxane
rings with a Short Spacer between the rings
[0093] Cyclic SiH-containing siloxanes, that is a representative Component A)'s, were made
by reacting MeH cyclics with VINYL SILOXANE #1, a dimethyvinyl-ended silicone having
on average 8 dimethylsiloxane units (DP = 8), in the presence of Pt catalyst. The
specific [SiH] / [Vi] ratio was kept at 3.0, 3.42, and 4.0 for the three examples
and the reaction was conducted at 40°C. The finished polymers were clear liquids having
the general structures shown in
Table 1. The SiH contents of these siloxanes were found to be 0.374%, 0.432%, and
0.505% respectively.

Example 2 (reference)
Preparation of an organohydrogensiloxane having at least two SiH containing cyclosiloxane
rings with a Long Spacer
[0094] Cyclic SiH-containing siloxanes (representative component A)) having a linear structure
with longer spacer were made by reacting MeH-cyclics with VINYL SILOXANE #2 (DP* =
130) in the presence of a Pt catalyst. The [SiH] / [Vi] ratios were 3.0, 3.42, and
4.0 for the three examples and the reaction was conducted at 40°C. The finished SiH
siloxanes were clear liquids having the target structures shown in the Table 2. The
SiH content were found to be 0.020%, 0.0240%, and 0.0296% respectively. These siloxanes
were made in a silicone carrier fluid to reduce the final viscosity.

Example 3 (reference)
Preparation of an organohydrogensiloxane having at least two SiH containing cyclosiloxane
rings
[0095] Cyclic SiH-containing siloxanes having branched structures were made by reacting
MeH cyclics with dimethyvinyl-ended branched silicones or methyvinyl cyclics. Illustrated
in the Table 3 are the examples derived from VINYL SILOXANE #3 having about 30 dimethylsiloxane
repeat on each of the four branches, yielding a total of about 120 dimethylsiloxane
units (DP = 120) in the presence of the Pt catalyst. The [SiH] / [Vi] ratios were
kept at 3.42 and 4.0 for the three examples and the reaction was conducted at 40°C.
Separately, a component A) was made using VINYL SILOXANE #4. The SiH siloxanes were
clear liquids having the structures summarized in Table 3. The SiH contents were 0.241%,
0.290%, and 0.376% respectively.

Example 4 (reference)
Preparation of an organohydrogensiloxane having at least two SiH containing cyclosiloxane
rings
[0096] Organohydrogensiloxanes illustrative as component A) were prepared by mixing MeH
CYCLICS, VINYL SILOXANES (as listed in Table 4) or 1, 5 hexadiene, and (if used) D5
as a carrier fluid in a reaction flask. Then, the mixture was catalyzed by the addition
of 3-5 ppm of Pt (Pt catalyst solution containing 0.52 wt% Pt). The mixture was heated
to 50°C, causing an exothermic hydrosilylation reaction to occur, the temperature
was then maintained between 50 and 70°C for 3 hours. The amounts of MeH CYCLICS and
the alkenyl compound were calculated to yield a specific [SiH] / [Vi] ratio of 3.42.
The resulting organohydrogensiloxanes were clear liquids having the average structures
and properties summarized in Table 4.
Table 4
| Example # |
4A |
4B |
4C |
4D |
| Amount used for reaction |
|
|
|
| MeH CYCLICS, g |
73.65 |
33.07 |
11.84 |
166.76 |
| Alkenyl compound type |
VINYL SILOXANE #1 |
VINYL SILOXANE #5 |
VINYL SILOXANE #7 |
1,5-Hexadiene |
| Alkenyl compound mass, g |
126.35 |
166.93 |
228.11 |
33.24 |
| D5 Carrier fluid, g |
0 |
0 |
360.7 |
0 |
| Pt catalyst, g |
0.16 |
0.16 |
0.48 |
0.18 |
| Stabilizer, g |
0 |
0 |
3.0 |
0.25 |
| Total batch, g |
200.16 |
200.16 |
604.13 |
200.43 |
| Product appearance |
Clear, low viscosity |
Clear, low viscosity |
Clear, moderate viscosity |
Clear, moderate viscosity |
| Wt. % [H] |
0:4319 |
0.1939 |
0.0231 |
0.978 |
| Mn, g/mole |
3,814 |
9,131 |
22,167 |
1,128 |
| Mw, g/mole |
18,688 |
78,303 |
39,103 |
1,591 |
Example 5 (reference)
Preparation of A) organohydrogensiloxanes having at least two SiH containing cyclosiloxane
rings
[0097] Additional examples of the cyclic SiH-bearing siloxanes were made as shown below
using component B as listed and MeH CYCLICS as component a).
Table 5. Cyclic SiH siloxanes
| Example # |
Component B |
Comments |
Wt. % [H] |
Mn, g/mol |
Mw, g/mol |
| 5A |
1,5-Hexadiene |
SiH/diene @ 4.50; as made |
1.06 |
418 |
770 |
| 5B |
1,5-Hexadiene |
SiH/diene @ 4.50; VAP stab. |
1.06 |
415 |
760 |
| 5C |
Vinyl-siloxane #5 |
SiH/vinyl @ 3.42; VAP stab.; made @ 100% solids |
0.4320 |
|
|
| 5D |
Vinyl-siloxane #5 |
SiH/vinyl @ 3.42; VAP stab.; made @ 100% solids |
0.1939 |
9114 |
59590 |
| 5E |
Vinyl-siloxane #6 |
SiH/vinyl @ 3.42; VAP stab.; made @ 80% solids in D5 fluid |
0.1214 |
9721 |
36052 |
| 5F |
Vinyl-siloxane #7 |
SiH/vinyl @ 3.42; made 40% solids in D5 fluid, VAP stab. |
0.0231 |
14051 |
70697 |
| 5G |
Vinyl-siloxane #7 |
SiH/vinyl @ 4.0, 40% solids in D5 fluid; VAP stab. |
0.0285 |
26284 |
66219 |
| 5H |
Vinyl-siloxane #7 |
SiH/vinyl @ 3.42; VAP stab.; made @ 50% solids in D5 fluid |
0.0289 |
29721 |
100166 |
| 5I |
Vinyl-siloxane #8 |
SiH/vinyl @ 4.0, VAP stab., made 40% solids in D5 fluid |
0.0237 |
44482 |
203232 |
| 5J |
Vinyl-siloxane #1 |
SiH/vinyl @ 3.42; VAP stab.; made @ 100% solids |
0.4319 |
3658 |
8781 |
| 5K |
Vinyl-siloxane #5 |
SiH/vinyl @ 3.42; VAP stab.; made @ 100% solids |
0.1939 |
7924 |
21167 |
Example 6
Preparation of Silicone Elastomer Gels from Cyclic SiH Siloxane at Low [SiH] / [Alkeny/] Ratio
[0098] Silicone elastomer gels were prepared by reacting the organohydrogensiloxane having
at least two SiH containing cyclosiloxane rings as component (A) and aliphatic unsaturated
compound as component (B) at a low [SiH] / [Alkeny] ratio of 0.36. Cyclic SiH siloxane
of Example 5F a 40% solids in D5 fluid where the cyclic SiH-containing siloxane made
from MeH-CYCLICS and VINYL SILOXANE #7 at a SiH/alkenyl ratio of 3.42, was reacted
with VINYL SILOXANE #2 in D5 fluid and in isodecyl neopentanoate (IDNP) hydrocarbon
ester solvent. Table 6 summarizes the reactions and subsequent gels produced.

Example 7
Preparation of Silicone Elastomer Gels
[0099] Silicone elastomer gels were made with a low elastomer contents (EC), as illustrated
in this example. Silicone elastomer gels (Example 7A and 7C) were made at 3.0 % elastomer
composition (the total of components (A) and (B)), and 97 % D5 fluid (component (D)).
The siloxane spacer had an average DP (degree of polymerization) of 100 in these examples.

Example 8
Silicone Elastomer Gels Made at Low Elastomer Content
[0100] Silicone elastomer gels were prepared with low amounts of elastomer content using
cyclic SiH-containing siloxanes of relatively short spacer (i.e. low dp). Illustrated
below are the silicone elastomer gels made from the SiH siloxane of Example 4C (8
dp spacer) and Example 4D (27dp spacer). All gels in this example had 5 wt% elastomer
content (i.e. total of components (A) and (B)), and 95% D5 fluid (component (C)).

Example 9
Preparation of Silicone Elastomer Blends from Cyclic SiH Siloxanes:
[0101] Silicone elastomer blends (SEBs) are discrete crosslinked silicone elastomer gel
particles dispersed in carrier fluids. SEBs can function effectively as a rheological
thickener for silicone fluids such as D5 fluid as demonstrated in this example.
To make silicone elastomer blends, the elastomer gels of known initial elastomer content
(IEC) from several of the above examples were mechanically sheared to obtain small
particle size and further diluted to desirable final elastomer content (FEC). For
example, sample 9A SEB was made by mechanically shearing an elastomer gel to reduce
particle size and then diluted further with D5 fluid to yield a final elastomer content
(% FEC) of 10% by weight. The final SEB was a clear thick gel paste with a viscosity
of about 676,000 cps. Additional SEBs are shown in Table 9. As illustrated by these
examples, extremely high viscosities were observed for these compositions of SEBs
in cyclic siloxanes.
Table 9: Silicone elastomer blends derived from elastomer gels of cyclic SiH-bearing
siloxane
| Example # |
9A |
9B |
9C |
9E |
9F |
| Gel composition |
|
|
|
|
|
| SiH (component (A)) |
Example 5E 37dp |
Example 5H 100dp |
Example 5H 100dp |
Example 5H 100dp |
Example 5H 100dp |
| Vinyl extender (component (B) |
Vinyl siloxane #2 |
Vinyl siloxane #2 |
Vinyl siloxane #2 |
Vinylsiloxane #6 |
Vinyl siloxane #7 |
| Carrier fluid (component D) |
D5 fluid |
D5 fluid |
D5 fluid |
D5 fluid |
D5 fluid |
| % IEC in the elastomer gel |
20 |
20 |
10 |
20 |
20 |
| Dilution fluid |
D5 fluid |
D5 fluid |
D5 fluid |
D5 fluid |
D5 fluid |
| % FEC in final SEB |
10.0 |
10.0 |
10.0 |
10.0 |
10.0 |
| Viscosity of SEB, cps |
676,000 |
534,950 |
976,150 |
309,750 |
692,400 |
Example 10
Example of Silicone Elastomer Gels prepared neat
[0102] Silicone elastomer gels can be prepared without a carrier fluid present, as illustrated
in this example. The total of components (A) and (B) represents the elastomer amount
and is equal to 100% in these examples.
[0103] Silicone elastomer gels were made from the hydrosilylation of the representative
cyclic SiH-containing siloxane as component (A) with an alkenyl functional compound
in component (B) in the presence of Pt catalyst. The two cyclic SiH siloxanes used
for the preparation of 100% silicone elastomer gels were those described above as
Example 4J, and example 4K. The molar ratio of silicon-bonded hydrogen [SiH] to [alkenyl]
was 0.90. The hardness of these silicone elastomer gels, as measured by Texture Analyzer,
is shown in the Tables 10A and 10B.
Table 10A. Comnosition and property and silicone gels of 100% elastomer content
| Example # |
10A |
10B |
10C |
| Component (A) |
Example 5K 8dp PDMS spacer; SiH/Alkenyl @ 3.42 |
Example 5K 8dp PDMS spacer; SiH/Alkenyl @ 3.42 |
Example 5K 8dp PDMS spacer; SiH/Alkenyl @ 3.42 |
| Component (B) |
Vinyl siloxane #2 |
Vinyl siloxane #8 |
Vinyl-siloxane #10 |
| Component (D): Carrier fluid type |
None |
None |
None |
| [SiH] / [Alkenyl) ratio in gel |
0.90 |
0.90 |
0.90 |
| % Elastomer content |
100.0 |
100.0 |
100.0 |
| Cure temperature |
70 °C |
70 °C |
70 °C |
| Actual amount |
|
|
|
| Component (A), g |
7.98 |
5.41 |
3.19 |
| Component (B), g |
82.07 |
84.73 |
86.89 |
| Pt catalyst, g |
0.07 |
0.07 |
0.07 |
| Total Batch, g |
90.12 |
90.21 |
90.15 |
| Gel appearance |
Clear, rigid |
Clear, rigid |
Clear, rigid |
| Texture Analyzer, Force 1, g of gel |
2617 |
2778 |
1902 |
| Texture Analyzer, Area F-T 1:2, g.sec |
10,959 |
13,434 |
9,904 |
| Gel hardness (compression strength), N/m2 |
2.02 x 105 |
2.15 x 105 |
0.147 x 104 |
| Gel Viscosity as derived from F-T 1:2, N.s/m2 |
84.82 x 105 |
10.40 x 105 |
7.66 x 105 |
Table 10B. Composition and property and silicone gels of 100% elastomer content
| Example # |
10D |
10E |
10F |
| Component (A) |
Example 5J 27dp PDMS spacer; SiH/Alkenyl @ 3.42 |
Example 5J 27dp PDMS spacer; SiH/Alkenyl @ 3.42 |
Example 5J 27dp PDMS spacer; SiH/Alkenyl @ 3.42 |
| Component (B) |
Vinyl siloxane #6 |
Vinyl siloxane #7 |
Vinyl siloxane #2 |
| Component (D): Carrier fluid type |
None |
None |
None |
| [SiH] / [Alkenyl] ratio in gel |
0.90 |
0.90 |
0.90 |
| % IEC |
100.0 |
100.0 |
100.0 |
| Cure temp / condition |
70 °C |
70 °C |
70 °C |
| Actual amount |
|
|
|
| Component (A), g |
11.831 |
4.560 |
3.750 |
| Component (B), g |
78.19 |
85.49 |
86.264 |
| Pt catalyst, g |
0.08 |
0.08 |
0.08 |
| Total Batch, g |
78.27 |
85.567 |
86.344 |
| Gel appearance |
Clear, rigid |
Clear, rigid |
Clear, rigid |
| Texture Analyzer, Force 1, g of gel |
6327 |
4131 |
3590 |
| Texture Analyzer, Area F-T 1:2, g.sec |
33,947 |
21,808 |
19,391 |
| Gel hardness (compression strength), N/m2 |
4.90 x 105 |
3.20 x 105 |
2.78 x 105 |
| Gel Viscosity as derived from F-T 1:2, N.s/m2 |
26.28 x 105 |
16.88 x 105 |
15.01 x 105 |
The silicone elastomer blends were made from the silicone elastomer gels of 100% elastomer
content, by grinding/ shearing the gels, followed by diluting with the selected carrier
fluid, either silicone fluids or organic solvents.
Example 11
Hardness Property of Selected Silicone Elastomers/ Gels:
[0104] A number of silicone elastomer gels were prepared following the procedures described
above. These silicone elastomer gels were made from the selected cyclic SiH-containing
siloxane as component (A), the alkenyl functional compound in component (B), and the
balance quantity of D5 fluid. A trace amount of Pt catalyst at a quantity about 4-10
ppm Pt was used to catalyzed the reaction. The molar ratio of silicon-bonded hydrogen
[SiH] to [alkenyl] was varied, as shown in the following table. The hydrosilylation
reaction was carried out at 50°C for 4 hours. Gels formed from 15 minutes to 2 hours
after placing in 50 °C water bath, depending on the composition.
[0105] The hardness of the silicone elastomer gels derived was characterized using the Texture
Analyzer. The "Force 1" is the force reading at the maximum point of the force vs.
probe penetration time cure, illustrated in the above figure. This force reading represents
the firmness or hardness of the gels in resisting probe penetration. The second property
included is the "Force-Time 1:2 Area" reading. This is the area integration between
the maximum force reading and the time it elapsed (1 second in this case). This value
represents the elastic nature of the silicone elastomer gels. The higher the value,
in both properties, the harder the gels is. As illustrated, silicone elastomer gels
with a wide range of hardness are produced.
Table 11 Gel hardness of various SEBs
| Silicon Elastomer Gel Example # |
Component (A): SiH Type & Structure |
Component (B) compound |
[SiH] / [Alkenyl] ratio in gel |
Force 1, g |
Force-Time 1:2 Area, g.sec |
Gel hardness, N/m2 |
Gel viscosity, N.s/m2 |
| 11A |
8dp spacer; SiH/Alkenyl @ 3.42 |
130 dp |
0.80 |
230 |
1249 |
1.78 x 104 |
9.67 x 104 |
| 11B |
8dp spacer; SiH/Alkenyl @ 3.42 |
130 dp |
1.10 |
612 |
2844 |
4.74 x 104 |
22.01 x 104 |
| 11C |
8dp spacer; SiH/Alkenyl @ 3.42 |
130 dp |
1.30 |
600 |
3299 |
4.64x 104 |
25.53 x 104 |
| 11D |
8dp spacer; SiH/Alkenyl @ 3.42 |
200 dp |
1.00 |
242 |
1307 |
1.87 x 104 |
10.12 x 104 |
| 11E |
Q-branched, 120dp total; @ 3.42 |
200 dp |
0.95 |
149 |
806 |
1.15 x 104 |
6.24 x 104 |
| 11F |
C6 organic spacer; SiH/Alkenyl @ 3.42 |
130 dp |
0.85 |
142 |
746 |
10.10x 104 |
5.77 x 104 |
| 11G |
C6 organic spacer; SiH/Alkenyl @ 3.42 |
130 dp |
1.00 |
391 |
1919 |
3.03 x 104 |
14.85 x 104 |
| 11H |
C6 organic spacer; SiH/Alkenyl @ 3.0 |
200 dp |
0.90 |
112 |
612 |
0.867 x 104 |
4.74 x 104 |
| 11l |
C6 organic spacer; SiH/Alkenyl @ 4.0 |
200 dp |
1.00 |
145 |
785 |
1.12 x 104 |
6.08 x 104 |
| 11J |
C6 organic spacer; SiH/Alkenyl @ 3.0 |
220 dp; Q-branched |
1.00 |
562 |
2671 |
4.35 x 104 |
20.67 x 104 |
| 11H |
with mixed (C6 organic / 8 dp @ 50/50) @ 3.42 |
200 dp |
0.95 |
59 |
318 |
0.457 x 104 |
2.46 x 104 |
Example 12
Silicone Gels Hardness Measured by the Texture Analyzer
[0106] Elastomer gels with very low hardness (soft gels) and with very high hardness readings
(not shown yet) can be conveniently prepared by controlling the % elastomer content.
The total of components (A) and (B) represents the elastomer content and can be as
high as 100%. In the case of neat elastomers, the hardness of such gels is very high
and can be processed into powdery type products to give a powdery feel.
[0107] Illustrated in the Table 12, gels were prepared from various component (A) and alkenyl-functional
compound in component (B) to 10 and 20% elastomer content. Dow Corning 245 fluid was
used as component (D). Very soft gels with a force of 4 g were produced. On the other
hand, gels with very high force readings may be produced from these components by
raising the wt. % elastomer content.
Table 12 Silicone gels with different hardness
| Silicone Elastomer Gel Example # |
Component (A): SiH Type & Structure |
Component (B): dp of Alkenyl Compound |
Wt.% Elastomer; (A) + (B) |
Force 1, g |
Force-Time 1:2 Area, g.sec |
Gel hardness, N/m2 |
Gel viscosity, N.s/m2 |
| 12A |
27 dp ; made 80% solids in D5 fluid |
130 dp |
20.0 |
161 |
864 |
1.24 x 104 |
6.69 x 104 |
| 12B |
27 dp ; made 80% solids in D5 fluid |
200 dp |
20.0 |
106 |
582 |
0.82 x 104 |
4.50 x 104 |
| 12C |
37 dp ; made 80% solids in D5 fluid |
37 dp |
20.0 |
46 |
263 |
0.356 x 104 |
2.04 x 104 |
| 12D |
37 dp ; made 80% solids in D5 fluid |
37 dp |
10.0 |
4 |
30 |
0.031 x 104 |
0.232 x 104 |
| 12E |
37 dp ; made 80% solids in D5 fluid |
130 dp |
20.0 |
192 |
1037 |
1.49 x 104 |
8.03 x 104 |
| 12F |
100 dp ; made 50% solids in D5 fluid |
130 dp |
20.0 |
139 |
780 |
1.08 x 104 |
6.04 x 104 |
| 12G |
100 dp; made 50% solids in D5 fluid |
130 dp |
10.0 |
29 |
171 |
0.224 x 104 |
1.32 x 104 |
| 12H |
100 dp; made 50% solids in D5 fluid |
100 dp |
20.0 |
194 |
1054 |
1.50 x 104 |
8.16 x 104 |
| 12l |
100 dp; made 50% solids in D5 fluid |
100 dp |
10.0 |
38 |
221 |
0.294 x 104 |
1.71 x 104 |
| 12J |
100 dp ; made 50% solids in D5 fluid |
37 dp |
20.0 |
254 |
1403 |
1.97 x 104 |
10.86 x 104 |
| 12K |
130 dp ; made 50% solids in D5 fluid |
200 dp |
20.0 |
101 |
565 |
0.782 x 104 |
4-37 x 104 |
The actual force vs. probe penetration time cures obtained from Texture Analyzer for
a selected group of gels from Table 12 are shown in Figure 1.
Example 13
Additional examples of SEBs made at low SiH / vinyl ratios
[0108] Elastomers and gels may be formed over a wide range of SiH / vinyl ratios and at
relatively low SiH/vinyl ratios. To illustrate this, the following examples were prepared.
Component (A) in this example was an organohydrogensiloxane similar to Example 5F
with a 27dp siloxane spacer, made from MeH cyclics and VINYL SILOXANE #5 using a SiH/vinyl
ratio of 3.4.
| Example # |
13A |
13B |
13C |
13D |
13E |
13F |
| SiH:Vi ratio |
0.90 |
0.70 |
0.50 |
0.30 |
0.20 |
0.15 |
| Component (B): |
VINYL SILOXANE #7 |
VINYL SILOXANE #7 |
VINYL SILOXANE #7 |
VINYL SILOXANE #7 |
VINYL SILOXANE #7 |
VINYL SILOXANE #7 |
| Component (D): Carrier fluid type |
None |
None |
None |
None |
None |
None |
| Actual amount |
|
|
|
|
|
|
| Component (A): grams |
8.41 |
6.70 |
4.90 |
3.01 |
2:03 |
1.54 |
| Component (B): grams |
71.594 |
73.303 |
75.10 |
76.99 |
77.97 |
78.46 |
| Syl-Off 4000, g (0.052% Pt) |
0.05 |
0.05 |
0.05 |
0.05 |
0.05 |
0.05 |
| Total Batch, g |
80.052 |
80.057 |
80.051 |
80.053 |
80.056 |
80.052 |
| Gel / mixture appearance |
Clear solid gel |
Clear solid gel |
Clear solid gel |
Clear solid gel |
Clear solid gel |
Clear pourable liquid; no gel formed |
| Texture Analyzer, Force 1, g of gel |
3349 |
1749 |
491 |
44.3 |
3.0 |
|
| Texture Analyzer, Area F-T 1:2, g.sec |
18,036 |
9,136 |
2,548 |
243 |
23.4 |
|
| Gel hardness (compression strength), N/m2 |
25.9 x 104 |
13.5 x 104 |
3.80 x 104 |
0.343 x 104 |
0.023 x 104 |
|
| Gel Viscosity as derived from F-T 1:2, N.s/m2 |
13.96 x 105 |
7.07 x 105 |
1.97 x 105 |
0.188 x 105 |
0.018 x 105 |
|
Preparation: prescribed amounts of components (A) and (B) are charged to a reaction
container and mixed to homogeneous, then about 3.5ppm of Pt catalyst (i.e. 0.05 g
of Dow Corning Syl-Off Pt solution @ 0.52 % Pt by weight) was introduced while under
stirring. The hydrosilylation reaction was carried out at 70°C for 3 hrs. All mixtures
except Example 13F gelled within 30 minutes of heating. The gel hardness was characterized
using a Texture Analyzer.
Example 14 (Comparative Example)
Comparison Examples: Silicone elastomer gels from linear MeH siloxane / hexadiene chemistry
[0109] The thickening or gelling capabilities of representative SEBs of the present invention
were evaluated vs thickening capabilities of known silicone elastomers known in the
art for thickening such as those described in
US 5,811,487 and
US 5,880,210. Two silicone elastomer blend compositions were prepared using MD
94D'
6M SiH polymer (MeH Linear) and 1,5-hexadiene as chain extender, and amount of D5 fluid
as the carrier fluid to provide elastomer content of 10.0 and 5.0 % by weight. A water-white,
weak and soft gel was obtained for Example 8A, but was not as firm as Example 6A as
described above. No gel or elastomer was formed in the Example 8B composition, at
5.0 % elastomer content. This example demonstrates the improved thickening and gel-forming
capacity of the cyclic SiH-containing siloxane based composition of the present invention
vs conventional linear siloxane based silicone elastomers of the art.
Table 8: Comparison silicone elastomer gels
| Example # |
8A |
8B |
| [SiH] / [Vi] ratio |
0.90 |
0.90 |
| Organohydrogensiloxane |
MeH Linear |
MeH Linear |
| %SiH in SiH Polymer |
0.068 |
0.068 |
| Vinyl compound |
1,5-Hexadiene |
1,5-Hexadiene |
| Carrier fluid type |
D5 |
D5 |
| % IEC |
10.0 |
5.0 |
| Cure temp / condition |
50 °C |
50 °C |
| Actual amount |
|
|
| MeH Linear, g |
29.14 |
14.581 |
| 1,5-Hexadiene, g |
0.88 |
0.433 |
| D5 fluid, g |
285.0 |
285.0 |
| Platinum catalyst, g (20 drops give 0.24g; 4.2 ppm) |
0.24 |
0.24 |
| Total Batch, g |
315.26 |
300.25 |
| Gel appearance |
Water-white, very soft gel |
Water-white clear liquid, low viscosity |
Example 15
Preparation of Silicone Elastomer Gels containing actives
[0110] Silicone Elastomer gels were prepared from cyclic SiH-containing siloxane having
various chain architectures (component A), as well as aliphatic unsaturated compounds
of various structure and type in component (B). The amounts and components (A) and
(B) were calculated to yield a predetermined [SiH] / [Alkeny] molar ratio and a pre-determined
% elastomer content in the cured gel. Examples 15B and 15D were charged with 7.15
wt% VAP during the formation of the silicone elastomer gel, and is representative
of the "pre-load method".
Table 15
| Example # |
15A |
15B |
15C |
15D |
| Component (A): reference |
4A |
4A |
4B |
4B |
| Component (B): Alkenyl Compound |
VINYL SILOXANE #2 |
VINYL SILOXANE #2 |
VINYL SILOXANE #2 |
VINYL SILOXANE #2 |
| [SiH] / [Alkenyl] mol. ratio |
0.90 |
1.00 |
0.90 |
1.00 |
| Component (C ): Carrier fluid |
D5 |
D5 |
D5 |
D5 |
| Component (E): Wt. % VAP in gel |
0.0 |
7.15 |
0.0 |
7.15 |
| Gel appearance |
Clear |
Clear, bright yellow |
Clear |
Clear, bright yellow |
| Wt. % IEC in gel |
20 |
20 |
20 |
20 |
| Vitamin Loading Method |
|
Pre-load |
|
Pre-load |
| Texture analyzer, Force 1, g |
143 |
120 |
171 |
135 |
| Texture analyzer, force-time 1-2, g.sec |
780 |
659 |
935 |
734 |
| Gel hardness, N/m2 |
11,068 |
9,288 |
13,236 |
10,449 |
| Viscosity of gel, N·s/m2 |
60,373 |
51,088 |
72,371 |
56,813 |
The silicone elastomer gels in these examples were prepared according to the following
procedures: 1) charge all components except catalyst to a glass container (or a reactor)
and stir to homogeneous; 2) catalyze the reaction mixture (with 3 - 5 ppm Pt) and
quickly place the mixture in a 70°C water bath and continue the stirring until the
mixture gelled, record the time it takes to reach the gel state; 3) leave the reaction
mixture container in the 70°C water bath for a total of 4 hrs.
Example 16
Preparation of Silicone Elastomer Gels containing actives
[0111] Silicone elastomer gels with and without a vitamin active were also derived from
organohydrogencyclositoxanes of varying molecular structure as shown in the examples
summarized in Table 16. The hardness of the VAP active containing silicone elastomer
gels was characterized by the Texture Analyzer, as described above. The gels were
prepared according to the procedure described in Example 15.
Table 16
| Example # |
16A |
16B |
16C |
16D |
| Component (A): Reference |
4C |
4C |
4D |
4D |
| Component (B): Alkenyl Compound |
VINYL SILOXANE #2 |
VINYL SILOXANE #2 |
VINYL SILOXANE #2 |
VINYL SILOXANE #2 |
| [SiH] / [Alkenyl] mol. ratio |
0.85 |
1.00 |
0.85 |
1.00 |
| Component (C ): Carrier fluid |
D5 |
D5 |
D5 |
D5 |
| Component (E): Wt. % VAP in gel |
0.0 |
7.15 |
0.0 |
7.15 |
| |
|
|
|
|
| Gel appearance |
Clear, firm gel |
Clear, bright yellow firm gel |
Clear, firm gel |
Clear, bright yellow, firm gel |
| Wt. % IEC in gel |
20 |
20 |
20 |
20 |
| Vitamin Loading Method |
Pre-load |
|
Pre-load |
| Texture analyzer, Force 1, g |
108 |
106 |
127 |
111 |
| Texture analyzer, force-time 1-2, g.sec |
590 |
582 |
633 |
609 |
| Gel hardness, N/m2 |
8,359 |
8,205 |
9,830 |
8,592 |
| Viscosity of gel, N·s/m2 |
45,667 |
45,048 |
48,995 |
47,138 |
Example 17
Preparation of Silicone Elastomer Gels
[0112] Silicone elastomer gels with and without a vitamin active were also derived from
organohydrogencyclosiloxanes having an organic spacer as shown in the examples summarized
in Table 17. The gels were prepared according to the procedure described in Example
15.
Table 17
| Example # |
17A |
17B |
| Component (A): reference e |
4D |
4D |
| Component (B): Alkenyl Compound |
Vinyl siloxane #2 |
Vinyl siloxane #2 |
| Component (C): Carrier fluid |
D5 fluid |
D5 fluid |
| [SiH] / [Alkenyl] mol. Ratio in gel |
0.85 |
1.00 |
| Component (D): vitamin active % |
0.00 |
7.15 |
| |
|
|
| Silicone gel appearance |
Clear, yellowish gel |
Clear, yellowish gel |
| % Elastomer in Gel |
20.0 |
20.0 |
| Vitamin Loading Method |
Pre-load |
| Texture analyzer, Force 1, g |
142.0 |
103.5 |
| Texture analyzer, force-time 1-2, g.sec |
746 |
566 |
| Gel hardness, N/m2 |
10,991 |
8,011 |
| Viscosity of gel, N·s/m2 |
57,742 |
43,809 |
Example 18
Preparation of Silicone Elastomer Gels containing actives
[0113] Additional examples of silicone elastomer gels prepared from various organohydrogencyclosiloxanes
using the Example 3 procedures are summarized Table 18.
Table 18
| Example # |
18A |
18B |
18C |
18D |
| Component (A): reference |
4A |
4A |
4B |
4B |
| Component (B): Alkenyl Compound |
VINYL SILOXANE #2 |
VINYL SILOXANE #2 |
VINYL SILOXANE #2 |
VINYL SILOXANE #2 |
| Component (C ): Carrier fluid |
D5 |
D5 |
D5 |
D5 |
| [SiH] / [Alkenyl] mol. Ratio in gel |
0.90 |
1.00 |
0.90 |
1.00 |
| Component (E): vitamin active % |
0.00 |
7.15 |
0.00 |
7.15 |
| |
|
|
|
|
| Silicone gel apparance |
Clear, yellowish gel |
Clear, yellowish gel |
Clear, yellowish gel |
Clear, yellowish gel |
| % Elastomer in Gel |
20.0 |
20.0 |
20.0 |
20.0 |
| Vitamin Loading Method |
Pre-load |
|
Pre-load |
| Texture analyzer, Force 1, g |
|
|
130.6 |
148.0 |
| Texture analyzer, force-time 1-2, g.sec |
|
|
711 |
803 |
| Gel hardness, N/m2 |
|
|
10,109 |
11,455 |
| Viscosity of gel, N·s/m2 |
|
|
55,033 |
62,154 |
Example 19
Preparation of Silicone Elastomer Blends containing actives
[0114] Silicone elastomer blends were prepared from several of the silicone elastomer gels
by mechanically shearing a silicone elastomer gel composition characterized as having
an initial elastomer content (IEC) to reduce particle size, and subsequently diluting
the mixture with additional carrier fluid to a desired final elastomer content (FEC).
Various silicone elastomer blends, as summarized in Table 19, were made by mechanically
shearing silicone gel compositions using a Hauschild mixer to reduced particle size
and then diluted further with Dow Coming 245 fluid to yield silicone elastomer blends
having a final elastomer content (FEC) of 10% by weight. The silicone blend compositions
of these examples contained VAP, which can be included using the pre-load method (Example
19B and 19D), or from post-loading the VAP by its addition to a silicone gel composition
(Example 19A and 19C).
Table 19
| Example # |
19A |
19B |
19C |
19D |
| Gel Example # reference |
15A |
15B |
15C |
15D |
| Component (C ): Carrier fluid |
D5 fluid |
D5 fluid |
D5 fluid |
D5 fluid |
| |
|
|
|
|
| Component (E): Wt. % VAP in SEB |
3.53 |
3.58 |
3.53 |
3.58 |
| Vitamin Loading Method |
Post-load |
Pre-load |
Post-load |
Pre-load |
| Wt % Elastomer Content in SEB |
10.0 |
10.0 |
10.0 |
10.0 |
| SEB appearance |
Clear bright yellowish, smooth gel |
Clear bright yellowish, smooth gel |
Clear bright yellowish, smooth gel |
Clear bright yellowish, smooth gel |
| Viscosity of SEB (@ 10% FEC), cps |
255,000 |
342,000 |
227,000 |
677,000 |
Example 20
Preparation of silicone Elastomer Blends containing actives.
[0115] Additional examples of silicone elastomer blends, prepared from various silicone
elastomer gels using the Example 7 procedures, are summarized Table 20.
Table 20
| Example # |
20A |
20B |
20C |
20D |
| Gel Example # reference |
16A |
16B |
16C |
16D |
| Component (C ): Carrier fluid |
D5 fluid |
D5 fluid |
D5 fluid |
D5 fluid |
| |
|
|
|
|
| Component (E): Wt. % VAP in SEB |
3.53 |
3.58 |
3.53 |
3.58 |
| Vitamin Loading Method |
Post-load |
Pre-load |
Post-load |
Pre-load |
| Wt. % Elastomer Content in SEB |
10.0 |
10.0 |
10.0 |
10.0 |
| SEB appearance |
Clear, bright yellowish, smooth gel |
Clear bright yellowish, smooth gel |
Clear bright yellowish, smooth gel |
Clear bright yellowish, smooth gel |
| Viscosity of SEB (@ 10% FEC), cps |
295,000 |
1,220,000 |
43,800 |
364,000 |
Example 21
Preparation of Silicone Elastomer Blends containing actives
[0116] Additional examples of silicone elastomer blends, prepared from various silicone
elastomer gels using the Example 19 procedures, are summarized Table 21.
[0117] High-performance liquid chromatography (HPLC) was used to verify the presence and
integrity of VAP active in SEBs. The details of the HPLC analysis techniques are summarized
below.
HPLC Assays for Vitamin A Palpitate in SEB
Standard Preparation
[0118] Standards were prepared by creating a stock solution of 1000 ug/ml VAP in hexane.
This was done by measuring 107.2 mg VAP into a 100 ml volumetric flask. The flask
was then filled to the 100 ml level with hexane. The stock solution was then diluted
into solutions with concentration of 4, 40, 100, 300, and 500 ug/ml. A calibration
curve was constructed using all standards from 4 to 1000 ug/ml.
SEB Sample Extraction
[0119] There were two methods of sample extraction used in this study. PXL SEB samples were
extracted using hexane only. This was done by adding 0.5 g SEB to 20 g hexane in a
vial. The formulation samples (Sepigel and body lotions) were extracted by adding
1 g of formulation sample with 10 g THF: IPA (1:1). The samples were then put on a
wrist action shaker for 2 hours of mixing. After mixing was complete the samples were
filtered into HPLC vials using 0.45 micron PTFE filters.
HPLC Conditions
[0120] The assays of VAP in this invention were performed on one of the two HPLC systems:
a Waters 600E HPLC equipped with a Waters 991 PDA detector or Waters 2695 Separations
unit equipped with a Waters 2996 PDA detector. The column and column guard were Novapak
C18 from Waters. The column was heated to a constant temperature of 35° C. The mobile
phase was 45% methanol, 20% acrylnitrile, and 35% isopropanol set at a flow rate of
1 ml/min. 10 ul of each sample were injected and allowed to run for 12 minutes. The
PDA detector was set to 325 nm wavelength.
Table 21
| Example # |
21A |
21B |
21C |
21D |
| Gel Example # reference |
16A |
16B |
16C |
16D |
| Component (C ): Carrier fluid |
D5 fluid |
D5 fluid |
D5 fluid |
D5 fluid |
| % Elastomer in Gel |
20.0 |
20.0 |
20.0 |
20.0 |
| Composition of silicone elastomer blend |
| Silicone Gel, g |
50.00 |
50.00 |
50.02 |
50.03 |
| VAP active, g |
3.69 |
0 |
3.57 |
0 |
| D5 fluid, g |
46.34 |
50.0 |
46.45 |
50.03 |
| Batch total, g |
100.03 |
100.0 |
100.04 |
100.06 |
| |
|
|
|
|
| Vitamin Loading Method |
Post-load |
Pre-load |
Post-load |
Pre-load |
| Wt. % VAP in SEB, as formulated |
3.69 |
3.57 |
3.57 |
3.58 |
| Wt. % VAP in SEB, per HPLC |
3.29 |
3.57 |
3.36 |
3.39 |
| SEB Appearance as prepared |
Clear, yellowish gel |
Clear, yellowish gel |
Clear, yellowish gel |
Clear, yellowish gel |
| Wt. % Elastomer in SEB |
10.0 |
10.0 |
10.0 |
10.0 |
| Viscosity of SEB, cps |
183,000 |
412,000 |
194,000 |
515,000 |
Example 22
Preparation of Silicone Elastomer Blends containing actives
[0121] Additional examples of silicone elastomer blends, prepared from various silicone
elastomer gels using the Example 19 procedures, are summarized Table 22.
[0122] High-performance liquid chromatography (HPLC) was used to verify the presence and
integrity of VAP active in SEBs using the procedures as summarized in Example 21.
Table 22
| Example # |
22A |
22B |
| Gel Example # reference |
17A |
17B |
| Component (C ): Carrier fluid |
D5 fluid |
D5 fluid |
| % Elastomer in Gel |
20.0 |
20.0 |
| Composition of silicone elastomer blend |
|
| Silicone Gel, g |
50.04 |
50.05 |
| VAP active, g |
3.57 |
0 |
| D5 fluid, g |
46.47 |
50.05 |
| Batch total, g |
100.08 |
100.1 |
| |
|
|
| Vitamin Loading Method |
Post-load |
Pre-load |
| Wt. % VAP in SEB, as formulated |
3.57 |
3.58 |
| Wt. % VAP in SEB, per HPLC |
3.39 |
3.31 |
| SEB Appearance as prepared |
Clear, yellowish gel |
Clear, yellowish gel |
| Wt. % Elastomer in SEB |
10.0 |
10.0 |
| Viscosity of SEB, cps |
352,000 |
612,000 |
Example 23
Preparation of Silicone Elastomer Gels containing active without carrier fluids
[0123] Silicone elastomer gels were prepared without adding any carrier fluid (component
C) from various organohydrogencyclosiloxanes using Example 15 procedures. The formulations
and resulting gel properties are summarized Table 23.
Table 11A
| Example # |
23A |
23B |
23C |
| Component (A): reference |
4A |
4A |
4A |
| Component (B): Alkenyl extender type |
VINYL SILOXANE #2 |
VINYL SILOXANE #8 |
VINYL SILOXANE #10 |
| Component (C ): Carrier fluid type |
None |
None |
None |
| Component (E): Active type and wt.% |
Vitamin A Palmitate; 5% |
Vitamin A Palmitate; 5% |
Vitamin A Palmitate; 5% |
| [SiH] / [Alkenyl] ratio in gel |
0.95 |
0.95 |
0.95 |
| % Elastomer content |
95.0 |
95.0 |
95.0 |
| Cure temp / condition |
70 °C |
70 °C |
70 °C |
| Actual amount |
|
|
|
| Component (A), SiH, g |
7.99 |
5.29 |
3.16 |
| Component (B), alkenyl extender, g |
77.58 |
80.23 |
82.37 |
| Component (D): Pt catalyst (0.52%; Syl-Off 4000), g |
0.068 |
0.068 |
0.068 |
| Component (E): Vitamin A Palmitate / BHT mixture of 98.5/1.5, g |
4.57 |
4.55 |
4.57 |
| Total Batch, g |
90.21 |
90.14 |
90.17 |
| Gel appearance |
Light yellowish, milky |
Light yellowish, milky |
Light yellowish, milky |
| Texture Analyzer, Force 1, g of gel |
2916 |
1660 |
1330 |
| Texture Analyzer, Area F-T 1:2, g.sec |
15,847 |
8,974 |
7,233 |
| Gel hardness, N/m2 |
225,704 |
128,487 |
102,944 |
| Viscosity of gel, N·s/m2 |
1,226,586 |
694,604 |
559,847 |
Table 23B
| Example # |
23D |
23E |
23F |
| Component (A): SiH PXL type and structure |
4B |
4B |
4B |
| Component (B): Alkenyl extender type |
Vinyl Siloxane #6 |
Vinyl Siloxane #7 |
Vinyl Siloxane #2 |
| Component (C ): Carrier fluid type |
None |
None |
None |
| Component (E): Active type and wt.% |
Vitamin A Palmitate; 5% |
Vitamin A Palmitate; 5% |
Vitamin A Palmitate; 5% |
| [SiH] / [Alkenyl] ratio in gel |
0.90 |
0.90 |
0.90 |
| % IEC |
100.0 |
100.0 |
100.0 |
| Cure temp / condition |
70 °C |
70 °C |
70 °C |
| Actual amount |
|
|
|
| Component (A), SiH PXL, g |
11.776 |
4.510 |
3.755 |
| Component (B), alkenyl extender, g |
73.14 |
80.99 |
81.77 |
| Component (D): Pt catalyst (0.52%; Syl-Off 4000), g |
0.068 |
0.068 |
0.068 |
| Component (E): Vitamin A Palmitate / BHT mixture of 98.5/1.5, g |
4.57 |
4.58 |
4.56 |
| Total Batch, g |
89.55 |
90.15 |
90.15 |
| Gel appearance |
Almost clear, yellowish, firm gel |
Hazy to opaque yellowish, firm gel |
Milky opaque, light yellowish gel |
| Texture Analyzer, Force 1, g of gel |
5,667 |
2,744 |
3,658 |
| Texture Analyzer, Area F-T 1:2, g.sec |
30,940 |
14,847 |
19,835 |
| Gel hardness, N/m2 |
438,636 |
212,390 |
283,136 |
| Viscosity of gel, N·s/m2 |
2,394,811 |
1,149,184 |
1,535,264 |