[0001] The present invention relates to an inorganic particle-containing composition, a
transfer film comprising the same and a plasma display panel production process.
[0002] In recent years, much attention has been paid to a plasma display as a plate-like
fluorescent display. Fig. 1 is a schematic view showing the sectional shape of an
alternating current type plasma display panel (hereinafter sometimes referred to as
"PDP" for brevity). In this drawing, 1 and 2 denote glass substrates which are opposed
to each other, and 3 denotes a barrier rib. Cells are partitioned and formed by the
glass substrate 1, the glass substrate 2 and the barrier rib 3. 4 denotes a transparent
electrode fixed on the glass substrate 1; 5 denotes a bus electrode formed on the
transparent electrode 4 for the purpose of reducing the resistance of the transparent
electrode 4; 6 denotes an address electrode fixed on the glass substrate 2; 7 denotes
a fluorescent material held in the cell; 8 denotes a dielectric layer formed on the
surface of the glass substrate 1 so as to cover the transparent electrode 4 and the
bus electrode 5; 9 denotes a dielectric layer formed on the surface of the glass substrate
2 so as to cover the address electrode 6; and 10 denotes a protective film made of,
for example, magnesium oxide. Also, in color PDP, for the sake of obtaining a high-contrast
image, a color filter (red, green or blue) or a black matrix may be provided between
the glass substrate and the dielectric layer.
[0003] As a process of producing such PDP dielectric, barrier rib, electrode, fluorescent
material, color filter or black stripe (black matrix), there is suitably employed
a photolithography method of forming a photosensitive inorganic particle-containing
resin layer on a substrate, irradiating this film with ultraviolet light through a
photomask, developing the resulting film to retain a pattern on the substrate, and
baking the pattern.
[0004] The above photolithography method is theoretically excellent in pattern accuracy,
and especially in a method of using a transfer film, it is possible to form a pattern
having excellent uniformity of the thickness and uniformity of the surface. However,
a film forming material layer formed by coating an inorganic particle-containing composition
containing an acrylic resin on a base film did not have sufficient flexibility and
was insufficient in transferability.
[0005] For the purpose of solving these problems, it has been investigated to contain a
plasticizer, a dispersant, etc., in the film forming material layer. However, such
organic materials likely remain in the pattern after baking to cause coloration and
others. In particular, in the case where a sintered glass material such as a dielectric
layer is formed, there was a problem such that the light transmittance of the resulting
sintered glass material is liable to lower.
[0006] Under above circumstances, the present invention has been made.
[0007] A first object of the present invention is to provide an inorganic particle-containing
composition capable of suitably forming a constituent element of DPD (for example,
a barrier rib, an electrode, a resistor, a dielectric layer, a phosphor, a color filter,
and a black matrix) having excellent surface flatness.
[0008] A second object of the present invention is to provide an inorganic particle-containing
composition capable of forming a sintered glass material (for example, a dielectric
layer constituting PDP) having high light transmittance.
[0009] A third object of the present invention is to provide an inorganic particle-containing
composition capable of producing a transfer film having excellent flexibility in terms
of its film forming material layer.
[0010] A fourth object of the present invention is to provide an inorganic particle-containing
composition capable of producing a transfer film having excellent transferability
(heat adhesion to a substrate) in terms of its film forming material layer.
[0011] A fifth object of the present invention is to provide a transfer film capable of
efficiently forming a constituent element of PDP having excellent surface flatness.
[0012] A sixth object of the present invention is to provide a transfer film having excellent
flexibility in terms of its film forming material layer.
[0013] A seventh object of the present invention is to provide a transfer film having excellent
transferability (heat adhesion to a substrate) in terms of its film forming material
layer.
[0014] An eighth object of the present invention is to provide a PDP production process
capable of efficiently forming a constituent element of PDP having excellent surface
flatness.
[0015] A ninth object of the present invention is to provide a PDP production process capable
of efficiently forming PDP having high position accuracy in terms of its constituent
element.
[0016] A tenth object of the present invention is to provide a PDP production process capable
of efficiently forming a dielectric layer having a large thickness.
[0017] An eleventh object of the present invention is to provide a PDP production process
capable of efficiently forming a dielectric layer required for a large-sized panel.
[0018] A twelfth object of the present invention is to provide a process of producing PDP
having a dielectric layer having excellent uniformity in thickness.
[0019] A thirteenth object of the present invention is to provide a process of producing
PDP having a dielectric layer having excellent surface flatness.
[0020] The organic particle-containing composition of the present invention comprises
(A) inorganic particles; (B) a binder resin; and (C) a compound represented by the
following formula (I) (this compound is hereinafter referred to as "specific compound"):

wherein R1 represents a group represented by -CO-A, wherein A represents an alkyl group having
5-20 carbon atoms or an alkenyl group having 5-20 carbon atoms, and n is an integer of 2-20.
[0021] The organic particle-containing composition of the present invention may be a composition
further comprising (D) a radiation-sensitive component (this composition is hereinafter
referred to as "radiation-sensitive inorganic particle-containing composition").
[0022] The transfer film of the present invention comprises a film forming material layer
obtained from the above inorganic particle-containing composition.
[0023] A first production process of the present invention (hereinafter referred to as "PDP
production process (1)") comprises the steps of transferring a film forming material
layer obtained from the inorganic particle-containing composition according to the
present invention to a surface of a substrate and baking the transferred film forming
material layer to form a dielectric layer on the substrate.
[0024] A second production process of the present invention (hereinafter referred to as
"PDP production process (2)") comprises the steps of transferring a film forming material
layer obtained from the inorganic particle-containing composition according to the
present invention to a surface of a substrate; forming a resist film on the transferred
film forming material layer; exposing the resist film to form a latent image of a
resist pattern; developing the resist film to form the resist pattern; etching the
film forming material layer to form a pattern layer corresponding to the resist pattern;
and baking the pattern layer to form a constituent element selected from a barrier
rib, an electrode, a resistor, a dielectric layer, a phosphor, a color filter, and
a black matrix.
[0025] A third production process of the present invention (hereinafter referred to as "PDP
production process (3)") comprises the steps of forming a laminate film of a resist
film and a film forming material layer obtained from the inorganic particle-containing
composition according to the present invention on a base film; transferring the laminate
film formed on the base film to a surface of a substrate; exposing a resist film constituting
the laminate film to form a latent image of a resist pattern; developing the resist
film to form the resist pattern; etching the film forming material layer to form a
pattern layer corresponding to the resist pattern; and baking the pattern layer to
form a constituent element selected from a barrier rib, an electrode, a resistor,
a dielectric layer, a phosphor, a color filter, and a black matrix.
[0026] A fourth production process of the present invention (hereinafter referred to as
"PDP production process (4)") comprises the steps of transferring a film forming material
layer obtained from the inorganic particle-containing composition according to the
present invention to a surface of a substrate; exposing the film forming material
layer to form a latent image of a pattern; developing the film forming material layer
to form a pattern layer; and baking the pattern layer to form a constituent element
selected from a barrier rib, an electrode, a resistor, a dielectric layer, a phosphor,
a color filter, and a black matrix.
[0027] Fig. 1 is a schematic view showing the sectional shape of an alternating current
type plasma display panel.
[0028] Fig. 2A is a schematic sectional view showing a transfer film of the present invention;
and Fig. 2B is a sectional view showing the layer constitution of the transfer film.
[0029] Fig. 3 is a schematic sectional view showing an example of the steps of forming a
barrier rib in the production process of the present invention (transfer step, resist
film forming step and exposure step).
[0030] Fig. 4 is a schematic sectional view showing an example of the steps of forming a
barrier rib in the production process of the present invention (developing step, etching
step and baking step).
[0031] In the drawings:
- 1:
- Glass substrate
- 2:
- Glass substrate
- 3:
- Barrier rib
- 4:
- Transparent electrode
- 5:
- Bus electrode
- 6:
- Address electrode
- 7:
- Fluorescent material
- 8:
- Dielectric layer
- 9:
- Dielectric layer
- 10:
- Protective layer
- F1:
- Base film
- F2:
- Film forming material layer
- F3:
- Cover film
- 11:
- Glass substrate
- 12:
- Electrode
- 13:
- Dielectric layer
- 20:
- Transfer film
- 21:
- Film forming material layer
- 22:
- Base film
- 25:
- Barrier rib pattern layer
- 25A:
- Material layer remaining portion
- 25B:
- Material layer removed portion
- 31:
- Resist film
- 35:
- Resist pattern
- 35A:
- Resist remaining portion
- 35B:
- Resist removed portion
- 40:
- Barrier rib
- 50:
- Panel material
- M:
- Exposure mask
- MA:
- Light transmitting portion
- MB:
- Light shielding portion
[0032] The inorganic particle-containing composition of the present invention (which may
hereinafter be referred to as "composition" for simplicity) is described in detail
below.
[0033] The composition of the present invention comprises inorganic particles, a binder
resin and a specific compound, as essential components.
Inorganic Particles
[0034] An inorganic material constituting the inorganic particles constituting the composition
of the present invention is not particularly limited but can be properly selected
according to the application of a sintered material formed of the composition (type
of a constituent element of PDP).
[0035] The inorganic particles contained in the composition for forming a "dielectric layer"
or "barrier rib" constituting PDP are, for example, glass powders having a softening
point falling within a range of 350-700°C, preferably 400-620°C. When the softening
point of the glass powders is lower than 350°C, the glass powders are molten at the
stage that organic substances such as a binder resin have not been completely decomposed
and removed in the baking step of the film forming material layer made of the composition,
whereby part of the organic substances remain in the dielectric layer to be formed.
As a result, the dielectric layer is apt to be colored, and its light transmittance
tends to lower. On the other hand, when the softening point of the glass powders exceeds
700°C, a glass substrate is readily distorted because the glass powders must be baked
at a temperature higher than 700°C.
[0036] Specific examples of glass powders which are suitably used include (1) a mixture
of lead oxide, boron oxide and silicon oxide (PbO-B
2O
3-SiO
2), (2) a mixture of zinc oxide, boron oxide and silicon oxide (ZnO-B
2O
3-SiO
2), (3) a mixture of lead oxide, boron oxide, silicon oxide and aluminum oxide (PbO-B
2O
3-SiO
2-Al
2O
3), and (4) a mixture of lead oxide, zinc oxide, boron oxide and silicon oxide (PbO-ZnO-B
2O
3-SiO
2)
[0037] These glass powders may be contained in the composition for forming a constituent
element (such as an electrode, a resistor, a phosphor, a color filter, and a black
matrix) other than the dielectric layer and the barrier rib. The content of a glass
frit in the inorganic particle-containing composition for obtaining these panel materials
is usually 90% by weight or lower, and preferably 50-90% by weight, based on the whole
weight of the inorganic particles.
[0038] The inorganic particles contained in the composition for forming an "electrode" constituting
PDP are, for example, metal particles comprising Ag, Au, Al, Ni, Ag-Pd alloy, Cu,
Cr, or the like.
[0039] These metal particles may be contained in combination with the glass powders in the
composition for forming a dielectric layer. The content of the metal particles in
the dielectric layer forming composition is usually 10% by weight or lower, and preferably
0.1-5% by weight, based on the whole weight of the inorganic particles.
[0040] The inorganic particles contained in the composition for forming a "resistor" constituting
PDP are, for example, particles comprising RuO
2 or the like.
[0041] The inorganic particles contained in the composition for forming a "phosphor" constituting
PDP are, for example, particles comprising a red fluorescent material (such as Y
2O
3:Eu
3+, Y
2SiO
5:Eu
3+, Y
3Al
5O
12:Eu
3+, YVO
4:Eu
3+, (Y, Gd)BO
3:Eu
3+, and Zn
3(PO
4)
2:Mn), a green fluorescent material (such as Zn
2SiO
4:Mn, BaAl
12O
19:Mn, BaMgAl
14O
23:Mn, LaPO
4:(Ce, Tb), and Y
3(Al, Ga)
5O
12:Tb), a blue fluorescent material (such as Y
2SiO
5:Ce, BaMgAl
10O
17:Eu
2+, BaMgAl
14O
23:Eu
2+, (Ca, Sr, Ba)
10(PO
4)
6Cl
2:Eu
2+, and (Zn, Cd)S:Ag), or the like.
[0042] The inorganic particles contained in the composition for forming a "color filter"
constituting PDP are, for example, particles comprising a red material (such as Fe
2O
3 and Pb
3O
4), a green material (such as Cr
2O
3), a blue material (such as 2(Al
2Na
2Si
3O
10)·Na
2S
4), or the like.
[0043] The inorganic particles contained in the composition for forming a "black matrix"
constituting PDP are, for example, particles comprising Mn, Fe, Cr, or the like.
Binder Resin
[0044] The binder resin constituting the composition of the present invention is preferably
an acrylic resin.
[0045] When an acrylic resin is contained as the binder resin, the formed film forming material
layer exhibits excellent (heat) adhesion to a substrate. Accordingly, when the composition
of the present invention is applied to a base film to produce a transfer film, the
resulting transfer film has excellent transferability (heat adhesion to the substrate)
in terms of the film forming material layer.
[0046] The acrylic resin constituting the composition of the present invention is selected
among (co)polymers that have proper adhesion, can bind the inorganic particles and
are completely oxidized and removed by baking of the film forming material (at 400-620°C).
[0047] The acrylic acid includes homopolymers of a (meth)acrylate compound represented by
the following general formula (II), copolymers of two or more (meth)acrylate compounds
represented by the following general formula (II), and copolymers of a (meth)acrylate
compound represented by the following general formula (II) and a copolymerizable monomer.

wherein R
2 represents hydrogen atom or methyl group; and R
3 represents a monovalent organic group.
[0048] Specific examples of (meth)acrylate compounds represented by the general formula
(II) include:
alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl
(meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate,
t-butyl (meth)acrylate, pentyl (meth)acrylate, amyl (meth)acrylate, isoamyl (meth)acrylate,
hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate,
2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, isodecyl
(meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, lauryl (meth)acrylate,
stearyl (meth)acrylate, and isostearyl (meth)acrylate;
hydroxylalkyl (meth)acrylates such as hydroxyethyl (meth)acrylate, 2-hydroxypropyl
(meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl
(meth)acrylate, and 4-hydroxybutyl (meth)acrylate;
phenoxyalkyl (meth)acrylates such as phenoxyethyl (meth)acrylate and 2-hydroxy-3-phenoxypropyl
(meth)acrylate;
alkoxyalkyl (meth)acrylate such as 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate,
2-propoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, and 2-methoxybutyl (meth)acrylate;
polyalkylene glycol (meth)acrylates such as polyethylene glycol mono(meth)acrylate,
ethoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate,
phenoxypolyethylene glycol (meth)acrylate, nonylphenoxypolyethylene glycol (meth)acrylate,
polypropylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, ethoxypolypropylene
glycol (meth)acrylate, and nonylphenoxypolypropylene glycol (meth)acrylate;
cycloalkyl (meth)acrylates such as cyclohexyl (meth)acrylate, 4-butylcyclohexyl (meth)acrylate,
dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentadienyl
(meth)acrylate, bornyl (meth)acrylate, isobornyl (meth)acrylate, and tricyclodecanyl
(meth)acrylate; and
benzyl (meth)acrylate and tetrahydrofurfuryl (meth)acrylate.
[0049] Of these, (meth)acrylate compounds represented by the general formula (II) wherein
R
3 represents a group containing an alkyl group or an oxyalkylene group are preferred.
Particularly preferred (meth)acrylate compounds are butyl (meth)acrylate, ethylhexyl
(meth)acrylate, lauryl (meth)acrylate, isodecyl (meth)acrylate, and 2-ethoxyethyl
(meth)acrylate.
[0050] The other copolymerizable monomer is not particularly limited if it is a compound
copolymerizable with the (meth)acrylate compound. Examples of the other copolymerizable
monomer include unsaturated carboxylic acids such as (meth)acrylic acid, vinylbenzoic
acid, maleic acid, and vinylphthalic acid; and vinyl group-containing radical polymerizable
compounds such as vinylbenzyl methyl ether, vinyl glycidyl ether, styrene, α-methylstyrene,
butadiene, and isoprene.
[0051] The proportion of the comonomer derived from the (meth)acrylate compound represented
by the general formula (II) in the acrylic resin constituting the composition of the
present invention is usually 70% by weight or more, and preferably 90% by weight or
more.
[0052] Specific examples of preferred acrylic resins include polymethyl methacrylate, polybutyl
methacrylate, and a methyl methacrylate-butyl methacrylate copolymer.
[0053] In the formation of constituent elements of PDP utilizing a photoresist method as
described later, when the film forming material layer needs to be alkali-soluble for
etching, it is preferable that a carboxyl group-containing monomer is contained as
the above other copolymerizable monomer (comonomer). Specific examples of the carboxyl
group-containing monomer include acrylic acid, methacrylic acid, maleic acid, fumaric
acid, crotonic acid, itaconic acid, citraconic acid, mesaconic acid, cinnamic acid,
mono(2-(meth)acryloyloxyethyl) succinate, and ω-carboxy-polycaprolactone mono(meth)acrylate.
Of these, methacrylic acid is especially preferable.
[0054] Specific examples of preferred alkali-soluble resins include:
alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, propyl methacrylate,
isopropyl methacrylate, butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate,
pentyl methacrylate, amyl methacrylate, isoamyl methacrylate, hexyl methacrylate,
heptyl methacrylate, octyl methacrylate, isooctyl methacrylate, ethylhexyl methacrylate,
nonyl methacrylate, decyl methacrylate, isodecyl methacrylate, undecyl methacrylate,
dodecyl methacrylate, lauryl methacrylate, stearyl methacrylate, and isostearyl methacrylate;
hydroxylalkyl methacrylates such as hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate,
3-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl methacrylate,
and 4-hydroxybutyl methacrylate;
phenoxyalkyl methacrylates such as phenoxyethyl methacrylate and 2-hydroxy-3-phenoxypropyl
methacrylate;
alkoxyalkyl methacrylate such as 2-methoxyethyl methacrylate, 2-ethoxyethyl methacrylate,
2-propoxyethyl methacrylate, 2-butoxyethyl methacrylate, and 2-methoxybutyl methacrylate;
polyalkylene glycol methacrylates such as polyethylene glycol monomethacrylate, ethoxydiethylene
glycol methacrylate, methoxypolyethylene glycol methacrylate, phenoxypolyethylene
glycol methacrylate, nonylphenoxypolyethylene glycol methacrylate, polypropylene glycol
methacrylate, methoxypolypropylene glycol methacrylate, ethoxypolypropylene glycol
methacrylate, and nonylphenoxypolypropylene glycol methacrylate;
cycloalkyl methacrylates such as cyclohexyl methacrylate, 4-butylcyclohexyl methacrylate,
dicyclopentanyl methacrylate, dicyclopentenyl methacrylate, dicyclopentadienyl methacrylate,
bornyl methacrylate, isobornyl methacrylate, and tricyclodecanyl methacrylate; and
benzyl methacrylate and tetrahydrofurfuryl methacrylate.
[0055] Molecular weight of the acrylic resin constituting the composition of the present
invention is preferably 4,000-300,000, and more preferably 10,000-200,000; in terms
of weight average molecular weight as reduced into polystyrene by gel permeation chromatography
(hereinafter referred to as "GPC") (the molecular weight is hereinafter referred to
as "weight average molecular weight" for simplicity).
[0056] The proportion of the binder resin in the composition of the present invention is
preferably 5-80 parts by weight, and more preferably 10- 50 parts by weight, per 100
parts by weight of the inorganic particles. When the proportion of the binder resin
is too small, the binder resin cannot surely bind and hold the inorganic particles.
On the other hand, when the proportion is too large, the baking step may take a long
period of time, or the formed sintered material (for example, a dielectric layer)
may not have a sufficient strength or thickness.
Specific Compound
[0057] The specific compound is used as an additive having both effects of a plasticizer
and a dispersant. The composition of the present invention containing the specific
compound can reveal excellent surface flatness. Even when the obtained transfer film
is bent, the surface of the film forming material layer is finely cracked, and the
transfer film has excellent suppleness and can be rolled easily. Moreover, since the
specific compound is easily decomposed and removed by heat, a panel material obtained
by baking the film forming material layer is free from coloration, and in particular,
the light transmittance of a dielectric layer is not reduced.
[0058] In the formula (I) representing the specific compound, R
1 represents a group represented by -CO-A, wherein A represents an alkyl group having
5-20 carbon atoms or an alkenyl group having 5-20 carbon atoms, and
n is an integer of 2-20.
[0059] The alkyl group or alkenyl group represented by A has 5-20 carbon atoms, and preferably
9-18 carbon atoms. When the number of carbon atoms is less than 5, the function as
the additive may become insufficient. When it exceeds 20, the solubility in a solvent
of the additive constituting the inorganic particle-containing composition may lower,
and good flexibility may not be obtained.
[0060] Specific examples of the alkyl group include n-pentyl group, n-hexyl group, n-heptyl
group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group,
n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecyl
group, and n-eicosyl group.
[0061] Specific examples of the alkenyl group include 2-pentenyl group, 2-hexenyl group,
2-heptenyl group, 2-octenyl group, 2-decenyl group, 10-undecenyl group, 9-octadecenyl
group, and 9-octadecenyl group.
[0062] Of these, n-octyl group, n-dodecyl group, n-octadecyl group, and 9-octadecenyl group
are preferable, and 9-octadecenyl group is especially preferable.
[0063] In the formula (I), R
1 represents a group represented by -CO-A; and
n is an integer of 2-20.
[0064] Specific examples of the specific compound include diglycerin monolaurate, diglycerin
monostearate, diglycerin monooleate, and diglycerin monocaprylate. Of these, diglycerin
monooleate is especially preferable.
[0065] The proportion of the specific compound in the composition of the present invention
is preferably 0.1-20 parts by weight, and more preferably 0.5-10 parts by weight,
per 100 parts by weight of the inorganic particles. When the proportion of the specific
compound is too small, the surface flatness and flexibility of the film forming material
layer to be formed using the resulting composition cannot be sufficiently improved.
On the other hand, when it is too large, adhesion (tackiness) of the film forming
material layer to be formed using the resulting composition becomes too high so that
a transfer film comprising the film forming material layer may become inferior in
handling properties.
Radiation-Sensitive Component
[0066] The inorganic particle-containing composition of the present invention may be a radiation-sensitive
inorganic particle-containing composition containing a radiation-sensitive component.
Preferred examples of the radiation-sensitive component include (a) a combination
of a polyfunctional monomer and a radiation polymerization initiator and (b) a combination
of a melamine resin and a photo acid generator of forming an acid upon irradiation
with radiations. With respect to the combination (a), a combination of a polyfunctional
(meth)acrylate and a radiation polymerization initiator is especially preferable.
[0067] Specific examples of the polyfunctional (meth)acrylate constituting the radiation-sensitive
component include di(meth)acrylates of an alkylene glycol such as ethylene glycol
and propylene glycol; di(meth)acrylates of a polyalkylene glycol such as polyethylene
glycol and polypropylene glycol; di(meth)acrylates of a both terminal-hydroxylated
polymer such as both terminal-hydroxylpolybutadiene, both terminal-hydroxypolyisoprene,
and both terminal-hydroxypolycaprolactone; poly(meth)acrylates of a polyhydric alcohol
having a valency of 3 or more such as glycerin, 1,2,4-butanetriol, trimethylolalkanes,
tetramethylolalkanes, pentaerythritol, and dipentaerythritol; poly(meth)acrylates
of a cyclic polyol such as 1,4-cyclohexanediol and 1,4-benzenediol; and oligo (meth)acrylates
such as polyester (meth)acrylates, epoxy (meth)acrylate, urethane (meth)acrylate,
alkyd resin (meth)acrylate, silicone resin (meth)acrylate, and spiran resin (meth)arylate.
These polyfunctional (meth)acrylates can be used alone or in combination of two or
more thereof.
[0068] Specific examples of the radiation polymerization initiator constituting the radiation-sensitive
component include carbonyl compounds such as benzil, benzoin, benzophenone, camphorquinone,
2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone,
2-methyl-[4'-(methylthio)phenyl]-2-morpholino-1-propanone, and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one;
azo compounds or azide compounds such as azoisobutyronitrile and 4-azidobenzaldehyde;
organic sulfur compounds such as mercaptan disulfide; organic peroxides such as benzoyl
peroxide, di-tert-butyl peroxide, tert-butyl hydroperoxide, cumene hydroperoxide,
and p-methane hydroperoxide; trihalomethanes such as 1,3-bis(trichloromethyl)-5-(2'-chlorophenyl)-1,3,5-triazine
and 2-[2-(2-furanyl)ethylenyl]-4,6-bis(trichloromethyl)-1,3,5-triazine; and imidazole
dimers such as 2,2'-bis(2-chlorophenyl)-4,5,4',5'-tetraphenyl-1,2'-biimidazole. These
radiation polymerization initiators can be used alone or in combination of two or
more thereof.
Solvent
[0069] The composition of the present invention generally contains a solvent. Preferable
solvents are those that have good affinity with the inorganic particles and good solubility
of the binder resin, can impart appropriate viscosity to the resulting composition
and can be easily vaporized and removed upon drying.
[0070] Specific examples of the solvent include ketones such as diethyl ketone, methyl butyl
ketone, dipropyl ketone, and cyclohexanone; alcohols such as n-pentanol, 4-methyl-2-pentanol,
cyclohexanol, and diacetone alcohol; ether based alcohols such as ethylene glycol
monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether,
propylene glycol monomethyl ether, and propylene glycol monoethyl ether; unsaturated
aliphatic monocarboxylic acid alkyl esters such as n-butyl acetate and amyl acetate;
lactic acid esters such as ethyl lactate and n-butyl lactate; and ether based esters
such as methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl
ether acetate, and ethyl 3-ethoxypropionate. These solvents can be used alone or in
combination of two or more thereof.
[0071] The proportion of the solvent in the composition of the present invention is preferably
40 parts by weight or less, and more preferably 5-30 parts by weight, per 100 parts
by weight of the inorganic particles from the standpoint of maintaining the viscosity
of the composition within a preferred range.
[0072] The composition of the present invention may contain a variety of additives such
as a tackifier, a surface tension control agent, a stabilizer, and an antifoaming
agent as optional components, in addition to the above essential components.
[0073] Preferred examples of the composition for forming a dielectric layer as an example
of the inorganic particle-containing composition include a composition comprising
100 parts by weight of a mixture comprising 50-80% by weight of lead oxide, 5-30%
by weight of boron oxide, 0-20% by weight of zinc oxide, 0-10% by weight of aluminum
oxide and 0-10% by weight of silicon oxide, as inorganic particles (glass powders);
10-30 parts by weight of a butyl methacrylate/2-ethylhexyl methacrylate/hydroxypropyl
methacrylate copolymer as a binder resin;
0.1-10 parts by weight of diglycerin oleate as a specific compound; and
5-30 parts by weight of propylene glycol monomethyl ether and/or ethyl 3-ethoxypropionate
as a solvent.
[0074] The composition of the present invention can be prepared by kneading the above-described
inorganic particles, binder resin, specific compound, solvent and optional components
using a kneader such as a roll kneader, a mixer or a homomixer.
[0075] The thus prepared composition of the present invention is a pasty composition having
fluidity suitable for coating and usually has a viscosity of 1,000-30,000 cp, and
preferably 3,000-10,000 cp.
[0076] The composition of the present invention can be particularly advantageously used
for producing a transfer film (transfer film of the present invention) as described
in detail below.
[0077] The composition of the present invention can also be advantageously used in the conventional
method of forming a film forming material layer, that is, a method of forming a film
forming material layer by directly coating the composition on the surface of a substrate
by a screen printing method or the like and drying the coating film. Transfer Film
[0078] The transfer film of the present invention is a composite film that is advantageously
used in the step of forming a constituent element of PDP, especially the step of forming
a dielectric layer and is provided with a film forming material layer formed by coating
the composition of the present invention on a base film and drying the coating film.
[0079] That is, the transfer film of the present invention is constituted of a base film
having formed thereon a film forming material layer containing inorganic particles,
a binder resin and a specific compound.
[0080] The transfer film of the present invention may be a film (stack) obtained by forming
a resist film as described later on a base film, coating the composition of the present
invention on the resist film and drying the coating film.
[0081] Further, the transfer film of the present invention may be a radiation-sensitive
transfer film constituted using a radiation-sensitive inorganic particle-containing
composition.
(1) Constitution of transfer film:
[0082] Fig. 2A is a schematic sectional view showing the rolled transfer film of the present
invention, and Fig. 2B is a sectional view showing the layer constitution of the transfer
film (detail view of a portion (X)).
[0083] The transfer film shown in Fig. 2 is a composite film used for forming a dielectric
layer constituting PDP as an example of the transfer film of the present invention.
Usually, the transfer film is constituted of a base film F1, a film forming material
layer F2 that is formed on the surface of the base film F1 and can be peeled off,
and a cover film F3 that is provided on the surface of the film forming material layer
F2 and can be easily peeled off. The cover film F3 may not be used according to the
properties of the film forming material layer F2.
[0084] The base film F1 constituting the transfer film is preferably a resin film having
heat resistance and solvent resistance and having flexibility. When the base film
F1 has flexibility, the pasty composition (composition of the present invention) can
be coated using a roll coater, a blade coater, or the like, thereby making it possible
to form a film forming material layer having a uniform thickness and to store and
supply the formed film forming material layer in the form of a roll.
[0085] Examples of resins constituting the base film F1 include polyethylene terephthalate,
polyesters, polyethylene, polypropylene, polystyrene, polyimides, polyvinyl alcohol,
polyvinyl chloride, fluorine-containing resins such as polyfluoroethylene, nylon,
and cellulose. The base film F1 has a thickness of, for example, 20-100 µm.
[0086] The film forming material layer F2 constituting the transfer film is a layer that
becomes a sintered glass material (dielectric layer) upon baking and contains glass
powders (inorganic particles), a binder resin and a specific compound as essential
components.
[0087] The thickness of the resin forming material layer F2 varies depending upon the content
of the glass powders and the type and size of a panel but is, for example, 5-200 µm,
and preferably 10-100 µm. When the thickness is less than 5 µm, the thickness of the
finally formed dielectric layer becomes too small so that the prescribed dielectric
characteristics may not be ensured. Usually, when the thickness is 10-100 µm, the
thickness of the dielectric layer required for a large-sized panel can be sufficiently
ensured.
[0088] The cover film F3 constituting the transfer film is a film for protecting the surface
of the film forming material layer F2 (contact surface with the glass substrate).
This cover film F3 is preferably a resin film having flexibility. A resin forming
the cover film F3 is, for example, the resins for forming the base film F1 as described
above. The thickness of the cover film F3 is, for example, 20-100 µm.
(2) Production process of transfer film:
[0089] The transfer film of the present invention can be produced by forming the film forming
material layer (F2) on the base film (F1) and providing (press bonding) the cover
film (F3) on the film forming material layer (F2).
[0090] A method of forming the film forming material layer is, for example, a method of
coating the composition of the present invention containing inorganic particles, a
binder resin, a specific compound and a solvent on a base film and drying the coating
film to remove a part or the whole of the solvent.
[0091] Preferred examples of the method of coating the composition of the present invention
on the base film include a coating method using a roll coater, a coating method using
a blade coater such as a doctor blade, a coating method using a curtain coater, and
a coating method using a wire coater from the viewpoints that the thickness is large
(for example, 20 µm or more) and that a coating film having excellent uniformity in
thickness can be efficiently formed.
[0092] It is preferable that the surface of the base film on which the composition of the
present invention is coated is subjected to release treatment. Thus, the base film
can be easily peeled off from the film forming material layer after transferring the
film forming material layer.
[0093] The coating film of the composition of the present invention formed on the base film
is dried to remove a part or the whole of the solvent and turns into a film forming
material layer constituting the transfer film. Conditions for drying the coating film
made of the composition of the present invention include a temperature of 40-150°C
and a time of about 1-30 minutes. The proportion ofthe residual solvent after drying
(content of the solvent in the film forming material layer) is usually 10% by weight
or less, and preferably 0.1-5% by weight, from the viewpoint of revealing the tackiness
to the substrate and appropriate shape retention properties on the film forming material
layer.
[0094] It is preferable that the surface of the cover film provided (usually press bonded
under heating) on the thus formed film forming material layer is subjected to release
treatment as well. Thus, the cover film can be easily peeled off from the film forming
material layer prior to transferring the film forming material layer.
(3) Transfer of film forming material layer (method of use of transfer film):
[0095] The film forming material layer on the base film is transferred to the surface of
the substrate en bloc. According to the transfer film of the present invention, the
film forming material layer can be surely formed on the glass substrate through such
a simple operation. Accordingly, not only it is possible to make an improvement (enhance
efficiency) in the step of forming a constituent element of PDP such as a dielectric
layer, but also it is possible to improve the quality of the formed constituent element
(for example, to reveal stable dielectric characteristics in the dielectric layer).
PDP Production Process (1) (Formation of Dielectric Layer)
[0096] The PDP production process (1) of the present invention comprises the steps of transferring
a film forming material layer constituting the transfer film of the present invention
to the surface of a substrate and baking the transferred film forming material layer
to form a dielectric layer on the surface of the substrate.
[0097] An example of the step of transferring the film forming material layer of the transfer
film constituted as shown in Fig. 2 is as follows.
(1) The transfer film in the form of a roll is cut to a size corresponding to the
area of the substrate.
(2) After peeling off the cover film (F3) from the surface of the film forming material
layer (F2) of the cut transfer film, the transfer film is overlaid on the surface
of the substrate in such a manner that the surface of the film forming material layer
(F2) comes into contact with the substrate.
(3) A heating roll is moved over the transfer film overlaid on the substrate to press
bond the transfer film under heating.
(4) The base film (F1) is peeled off and removed from the film forming material layer
(F2) fixed to the substrate by press bonding under heating.
[0098] The film forming material layer (F2) on the base film (F1) is transferred to the
substrate by the above operation. Transfer conditions include a heating roll surface
temperature of 60-120°C, a heating roll pressure of 1-5 kg/cm
2, and a heating roll moving speed of 0.2-10.0 m/min. This operation (transfer step)
can be carried out using a laminator. The substrate may be preheated, and the preheating
temperature can be set up at, for example, 40-100°C.
[0099] The film forming material layer (F2) transferred to the surface of the substrate
turns into a sintered inorganic material (dielectric layer) by baking. The baking
method is, for example, a method of placing the substrate to which the film forming
material layer (F2) has been transferred in a high-temperature atmosphere. Thus, the
organic materials (for example, the binder resin, residual solvent, specific compound
and various additives) contained in the film forming material layer (F2) are decomposed
and removed, and the inorganic particles are molten and sintered. The sintering temperature
varies depending upon the melting temperature of the substrate, the constituent components
in the film forming material layer, and the like, but is, for example, 300-800°C,
and preferably 400-620°C.
PDP Production Process (2) (Formation of Constituent Element Utilizing Photoresist
Method)
[0100] The PDP production process (2) of the present invention includes the steps of transferring
a film forming material layer constituting the transfer film of the present invention
to a substrate; forming a resist film on the transferred film forming material layer;
exposing the resist film to form a latent image of a resist pattern; developing the
resist film to form the resist pattern; etching the film forming material layer to
form a pattern layer corresponding to the resist pattern; and baking the pattern layer
to form a constituent element selected from a barrier rib, an electrode, a resistor,
a dielectric layer, a phosphor, a color filter, and a black matrix.
[0101] Alternatively, the production process (2) of the present invention includes the steps
of forming a laminate film of a resist film and a film forming material layer obtained
from the inorganic particle-containing composition of the present invention on a base
film; transferring the laminate film formed to a surface of the base film on a substrate;
exposing a resist film constituting the laminate film to form a latent image of a
resist pattern; developing the resist film to form the resist pattern; etching the
film forming material layer to form a pattern layer corresponding to the resist pattern;
and baking the pattern layer to form a constituent element selected from a barrier
rib, an electrode, a resistor, a dielectric layer, a phosphor, a color filter, and
a black matrix.
[0102] A method of forming a "barrier rib" as the constituent element of PDP on the rear
surface of a substrate will be described below. This method comprises (1) the step
of transferring a film forming material layer, (2) the step of forming a resist film,
(3) the step of exposing the resist film, (4) the step of developing the resist film,
(5) the step of etching the film forming material layer, and (6) the step of baking
a barrier rib pattern, thereby forming a barrier rib on the surface of the substrate.
[0103] Fig. 3 and Fig. 4 are each a schematic sectional view showing a series of steps of
forming the barrier rib. In Fig. 3 and Fig. 4, 11 denotes a glass substrate on which
electrodes 12 for generating plasma are aligned at equal intervals, and a dielectric
layer 13 is formed on the surface of the glass substrate 11 so as to cover the electrodes
12.
[0104] In the present invention, the embodiment of "transferring a film forming material
layer to a substrate" includes not only an embodiment of transferring the film forming
material layer to the surface of the glass substrate 11 but also an embodiment of
transferring the film forming material layer to the surface of the dielectric layer
13.
(1) Step of transferring film forming material layer:
[0105] An example of the step of transferring a film forming material layer will be shown
as follows.
[0106] After peeling off a cover film (not shown) of the transfer film, as shown in Fig.
3B, a transfer film 20 is overlaid on the surface of the dielectric layer 13 in such
a manner that the surface of a film forming layer 21 comes into contact with the surface
of the dielectric layer 13, the transfer film 20 is press bonded under heating by
a heating roll, etc., and a base film 22 is then peeled off and removed from the film
forming material layer 21. Thus, as shown in Fig. 3C, the film forming material layer
21 is transferred and close bonded to the surface of the dielectric layer 13. Transfer
conditions include a heating roll surface temperature of 80-140°C, a heating roll
pressure of 1-5 kg/cm
2, and a heating roll moving speed of 0.1-10.0 m/min. The glass substrate 11 may be
preheated, and the preheating temperature can be set up at, for example, 40-100°C.
(2) Step of forming resist film:
[0107] In this step, as shown in Fig. 3D, a resist film 31 is formed on the surface of the
transferred film forming material layer 21. A resist constituting the resist film
31 may be any of a positive working resist and a negative working resist.
[0108] The resist film 31 can be formed by coating a resist by a variety of methods including
a screen printing method, a roll coating method, a rotation coating method, and a
cast coating method and drying the coating film. The drying temperature of the coating
film is generally about 60-130°C.
[0109] A resist film formed on the base film may be formed by transferring onto the surface
of the film forming material layer 21. According to this formation method, not only
the number of steps of forming the resist film can be reduced, but also the resulting
resist has excellent uniformity in the thickness. Accordingly, the development of
the resist film and the etching of the film forming material layer are uniformly carried
out, whereby the formed barrier rib becomes uniform in height and shape.
[0110] The resist film 31 usually has a thickness of 0.1-40 µm, and preferably 0.5-20 µm.
(3) Step of exposing resist film:
[0111] In this step, as shown in Fig. 3E, the surface of the resist film 31 formed on the
film forming material layer 21 is selectively irradiated (exposed) with radiations
such as ultraviolet light through an exposure mask M to form a latent image of a resist
pattern. In this drawing, MA and MB denote a light transmitting portion and a light
shielding portion formed by the exposure mask M, respectively.
[0112] An ultraviolet irradiation device is not particularly limited but may be an ultraviolet
irradiation device used for photolithography and an exposure device used for the production
of semiconductors and liquid crystal display devices.
[0113] When the resist film is formed by transfer, it is preferable to carry out the exposure
step in the state that the base film covered on the resist film is not peeled off.
(4) Step of developing resist film:
[0114] In this step, the exposed resist film is developed to form a resist pattern (latent
image).
[0115] Regarding developing conditions, the type, formulation and concentration of a developing
solution, the developing time, the developing temperature, the developing method (such
as immersion, rocking, shower, spray and puddling methods), the developing device,
and others can appropriately be selected according to the type of the resist film
31 and others.
[0116] A resist pattern 35 (pattern corresponding to the exposure mask M) constituted of
resist remaining portion 35A and resist removed portion 35B is formed by this developing
step as shown in Fig. 4F.
[0117] This resist pattern 35 serves as an etching mask in the subsequent step (etching
step), and the constituent material (photo-cured resist) of the resist remaining portions
35 must have a lower dissolution speed in an etching solution than the constituent
material of the film forming material layer 21.
(5) Step of etching film forming material layer:
[0118] In this step, the film forming material layer is etched to form a barrier rib pattern
layer corresponding to the resist pattern.
[0119] That is, as shown in Fig. 4G, portions corresponding to the resist removed portions
35B of the resist material 35 of the film forming material layer 21 are dissolved
in the etching solution and selectively removed. Fig. 4G shows the state during etching.
[0120] When etching is further continued, as shown in Fig. 4H, predetermined portions of
the film forming material layer 21 are completely removed, whereby the dielectric
layer 13 is exposed. Thus, a barrier rib pattern layer 25 constituted of material
layer remaining portions 25A and material layer removed portions 25B is formed.
[0121] Regarding the etching conditions, the type, formulation and concentration of the
etching solution, the treatment time, the treatment temperature, the treatment method
(such as immersion, rocking, shower, spray and puddling methods), the treatment device,
and others can appropriately be selected according to the type of the film forming
material layer 21 and others.
[0122] The type of the resist film 31 and the type of the film forming material layer 21
are selected such that the same solution as the developing solution used in the developing
step can be used as the etching solution, whereby it is possible to carry out the
developing step and the etching step continuously and to improve production efficiency
due to simplification of the steps.
[0123] It is preferable that the resist remaining portions 35A constituting the resist pattern
35 are gradually dissolved by etching and completely removed when the barrier rib
pattern layer 25 is formed (at the time of completion of etching).
[0124] Even when a part or the whole of the resist remaining portions 35A remain after etching,
the resist remaining portions 35A are removed in the subsequent baking step.
(6) Step of baking barrier rib pattern layer:
[0125] In this step, barrier ribs are formed by baking the barrier rib pattern layer 25.
Thus, the organic substances in the material layer remaining portions 25A are burnt
out to form barrier ribs. As shown in Fig. 4I, in a panel material 50 having barrier
ribs 40 formed on the surface of the dielectric layer 13, spaces partitioned by the
barrier ribs 40 (barrier ribs derived from the material layer removed portions 25B)
serve as plasma working spaces.
[0126] The baking temperature must be a temperature at which the organic substances in the
material layer remaining portions 25A are burnt out and is generally 400-600°C. The
baking time is generally 10-90 minutes.
PDP Production Process (3) (Preferred Embodiment Utilizing Photoresist Method)
[0127] The PDP production process (3) in the present invention is not limited to the process
shown in Fig. 3 and Fig. 4.
[0128] Other preferred process for forming the constituent element of PDP (PDP production
process (3)) is, for example, a forming method comprising the following steps (1)
to (3).
(1) After forming a resist film on a base film, the inorganic particle-containing
composition of the present invention is coated on the resist film and dried to laminate
and form a film forming material layer. In forming the resist film and the film forming
material layer, a roll coater or the like can be used, thereby making it possible
to form a laminate film having excellent uniformity in thickness on the base film.
(2) The laminate film consisting of the resist film and the film forming material
layer on the base film is transferred to a substrate. Transfer conditions may be the
same as those in the above-described "step of transferring film forming material layer".
(3) The same operations as described in the above-described "step of exposing resist
film", "step of developing resist film", "step of etching film forming material layer"
and "step of baking barrier rib pattern layer" are carried out. During these operations,
as described previously, it is preferable that the developing solution of the resist
film is made the same as the etching solution of the film forming material layer and
that the "step of developing resist film" and the "step of etching film forming material
layer" are carried out continuously.
[0129] According to the above method, since the film forming material layer and the resist
film are transferred to the substrate en bloc, production efficiency can be further
improved by simplification of the steps.
PDP Production Process (4) (Formation of Constituent Element Using Radiation-Sensitive
Transfer Film)
[0130] The PDP production process (4) of the present invention includes the steps of transferring
a film forming material layer constituting the radiation-sensitive transfer film of
the present invention to a substrate; exposing the film forming material layer to
form a latent image of a resist pattern; developing the film forming material layer
to form a pattern layer; and baking the pattern layer to form a constituent element
selected from a barrier rib, an electrode, a resistor, a dielectric layer, a phosphor,
a color filter, and a black matrix.
[0131] In this method, for example, when an example of the method of forming a barrier rib
is taken, after the above-described "step of transferring film forming material layer",
a pattern layer is formed under conditions according to the "step of exposing resist
film" and "step of developing resist film". Thereafter, a barrier rib is formed on
the surface of the substrate by the "step of baking barrier rib pattern".
[0132] The method of forming "barrier rib" as a constituent element of PDP has been described
in the explanation of the respective steps of the PDP production processes (1) to
(4). An electrode, a resistor, a dielectric layer, a phosphor, a color filter, and
a black matrix each constituting PDP can be formed according to this method.
[0133] The present invention will be described in more detail with reference to the following
Example, but it should be understood that the invention is not construed as being
limited thereto. In the Example and Comparative Examples, all "parts" are "parts by
weight".
EXAMPLE
(1) Preparation of glass paste composition (inorganic particle-containing composition):
[0134] A composition of the present invention having a viscosity of 3,400 cp (measured by
a B-type viscometer at 30 rpm) was prepared by kneading 100 parts of a PbO-B
2O
3-SiO
2 based mixture (softening point: 500°C) having a formulation consisting of 70% by
weight of lead oxide, 10% by weight of boron oxide and 20% by weight of silicon oxide,
15 parts of a butyl methacrylate/2-ethylhexyl methacrylate/hydroxypropyl methacrylate
copolymer (weight ratio: 30/60/10, weight average molecular weight: 150,000) as a
binder resin, 5 parts of diglycerin oleate as a specific compound, 8.7 parts of propylene
glycol monomethyl ether as a solvent, and 13.1 parts of ethyl 3-ethoxypropionate using
a dispersion mixer.
(2) Production and evaluation (flexibility and handling properties) of transfer film:
[0135] The composition of the present invention prepared in (1) above was coated on a base
film made of polyethylene terephthalate (PET) having been previously subjected to
release treatment (width: 400 mm, length: 30 m, thickness: 38 µm) using a blade coater,
and the formed coating film was dried at 80°C for 5 minutes to remove the solvent.
There was thus formed a film forming material layer having a thickness of 50 µm on
the base film. A cover film made of PET having been previously subjected to release
treatment (width: 400 mm, length: 30 m, thickness: 38 µm) was adhered to the film
forming material layer to produce a transfer film of the present invention having
the constitution shown in Fig. 2.
[0136] The resulting transfer film had suppleness and could be easily rolled. Further, even
when the transfer film was bent, it did not cause cracking (flex cracking) on the
surface of the film forming material layer, and the film forming material layer had
excellent flexibility.
[0137] The cover film was peeled off from the transfer film, the transfer film (laminate
consisting of the base film and the film forming material layer) was overlaid on a
glass substrate without applying pressure in such a manner that the surface of the
film forming material layer came into contact with the surface of the glass substrate,
and the transfer film was then peeled off from the surface of the glass substrate.
As a result, the film forming material layer showed appropriate tackiness to the glass
substrate, and the transfer film could be peeled off without causing cohesive failure
in the film forming material layer. Therefore, the transfer film had good handling
properties.
(3) Transfer of film forming material layer:
[0138] After peeling off the cover film from the transfer film obtained in (2) above, the
transfer film (laminate consisting of the base film and the film forming material
layer) was overlaid on a glass substrate for a 21-inch panel in such a manner that
the surface of the film forming material layer came into contact with the surface
(bus electrode fixed surface) of the glass substrate and press bonded under heating
using a heating roll. Press bonding conditions included a heating roll surface temperature
of 90°C, a roll pressure of 2 kg/cm
2, and a heating roll moving speed of 0.6 m/min.
[0139] After completion of the press bonding under heating, the base film was peeled off
and removed from the film forming material layer fixed (bonded under heating) to the
surface of the glass substrate, thereby completing transfer of the film forming material
layer.
[0140] In this transfer step, when the base film was peeled off, the film forming material
layer did not cause cohesive failure and had sufficiently large film strength. Further,
the transferred film forming material layer had good adhesion to the surface of the
glass substrate.
(4) Baking of film forming material layer (formation of dielectric layer):
[0141] The glass substrate on which the film forming material layer had been transferred
and formed in (3) above was placed in a kiln and baked by elevating the temperature
inside the kiln to 620°C to form an achromatic transparent dielectric layer made of
a sintered glass material on the surface of the glass substrate.
[0142] The thickness (average thickness and tolerance) of this dielectric layer was measured
and found to be in the range of 30 µm ± 0.4 µm. Thus, the dielectric layer had excellent
uniformity in thickness.
[0143] The surface of the resulting dielectric layer was subjected to three-dimensional
measurement using a non-contact thickness meter (NH-3, manufactured by Ryokosha Co.,
Ltd.) to determine the surface roughness (Ra, Ry, Rz) according to the JIS standards
(B0601). As a result, the dielectric layer had Ra = 0.08 µm, Ry = 0.56 µm and Rz =
0.28 µm so that it had excellent surface flatness.
[0144] Further, the light transmittance of the thus obtained dielectric layer was measured
(measurement wavelength: 550 nm) and found to be 93%. Thus, it was confirmed that
the dielectric layer had good transparency.
COMPARATIVE EXAMPLE
[0145] A composition having a viscosity of 3,000 cp (measured using a B-type viscometer
at 30 rpm) was prepared in the same manner as in the Example, except for changing
the proportion of the binder resin to 17 parts and using 4 parts of di-2-ethylhexyl
azelate in place of the specific compound. Using the resulting composition, a transfer
film was produced and evaluated in the same manners as in the Example. As a result,
the transfer film had good flexibility and handling properties. However, a dielectric
layer was formed in the same manner as in the Example and measured for surface roughness
(Ra, Ry, Rz). As a result, the dielectric layer had Ra = 0.65 µm, Ry = 2.51 µm and
Rz = 1.73 µm so that it was inferior in surface flatness.
[0146] The composition of the present invention gives rise to the following effects.
(1) It can suitably form a constituent element (for example, a barrier rib, an electrode,
a resistor, a dielectric layer, a phosphor, a color filter, and a black matrix) of
PDP having excellent surface flatness.
(2) It can suitably form a sintered glass material (for example, a dielectric layer
or barrier rib constituting PDP) having high light transmittance.
(3) It can produce a transfer film having excellent flexibility in terms of its film
forming material layer.
(4) It can produce a transfer film having excellent transferability (heat adhesion
to a substrate) in terms of its film forming material layer.
[0147] The transfer film of the present invention gives rise to the following effects.
(1) It can efficiently form a constituent element (especially a dielectric layer)
having excellent surface flatness of PDP.
(2) It is excellent in flexibility in terms of its film forming material layer, and
the surface of the film forming material layer is free from flex cracking (cracking).
(3) It has excellent suppleness and can be easily rolled.
(4) It is appropriate in adhesion and good in handling properties in terms of its
film forming material layer.
(5) It is excellent in transferability (heat adhesion to a substrate) in terms of
its film forming material layer.
[0148] The production process of the present invention gives rise to the following effects.
(1) It can efficiently form a constituent element (for example, a barrier rib, an
electrode, a resistor, a dielectric layer, a phosphor, a color filter, and a black
matrix) of PDP having excellent surface flatness.
(2) It can efficiently form PDP having high position accuracy of a constituent element.
(3) It can efficiently form a dielectric layer having a large thickness.
(4) It can efficiently form a dielectric layer required for a large-sized panel.
(5) It can efficiently form PDP provided with a dielectric layer having excellent
uniformity in thickness and surface flatness.
[0149] An inorganic particle-containing composition comprising:
(A) inorganic particles;
(B) a binder resin; and
(C) a compound represented by the following formula (I):

wherein R1 represents a group represented by -CO-A, wherein A represents an alkyl group having
5-20 carbon atoms or an alkenyl group having 5-20 carbon atoms, and n is an integer of 2-20.
A transfer film and a plasma display panel production process using the composition
are also described.