JPH11249293A - Manufacture of photosensitive paste and plasma display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide photosensitive paste making pattern work of a high aspect ratio and high accuracy possible. SOLUTION: Photosensitive paste contains (a) an ultraviolet ray absorber with absorption maximum in a wavelength area of 300-400 nm, (b) an antioxidant, (c) inorganic fine grain, and (d) a photosensitive organic component. The ultraviolet ray absorber is selected from a benzophenone compound, a cyanoacrylate compound, a benzotriazole compound and an indole compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The photosensitive paste of the present invention is
It is used for patterning and forming partition walls of plasma displays, plasma addressed liquid crystal displays, and the like.

[0002]

2. Description of the Related Art In recent years, miniaturization and high definition of circuit materials and displays have been advanced, and accordingly, a technique of pattern processing has been desired. In particular, a material capable of patterning an inorganic material such as glass with high precision and a high aspect ratio is desired for forming a partition of a plasma display.

Conventionally, when patterning an inorganic material, screen printing using a paste composed of an inorganic powder and an organic binder is often used. However, screen printing has a drawback that a pattern with high accuracy cannot be formed.

As a method for solving this problem, Japanese Patent Laid-Open No.
Japanese Patent Application Laid-Open Nos. 296534/1990, 165538/1993, and 354292/1993 propose a method of forming a pattern by a photolithography technique using a photosensitive paste.

However, in most of the photosensitive paste, only the surface layer is exposed (cross-linked), and the lower layer is insufficiently cured.
There has been a problem that the developed pattern meanders and the line width of the pattern head becomes large.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a photosensitive paste which solves the drawbacks of the prior art, does not require remodeling of an exposure machine, and can surely improve the pattern shape and resolution. It is in. Another object of the present invention is to provide a plasma display in which partition walls having high accuracy and a high aspect ratio are formed.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is as follows.
(A) an ultraviolet absorber having an absorption maximum in a wavelength region of 300 to 400 nm, (b) an antioxidant, (c) inorganic fine particles,
(D) This is achieved by a photosensitive paste containing a photosensitive compound.

Another object of the present invention is to provide a plasma display wherein the photosensitive paste is applied onto a substrate, and a partition pattern is formed by photolithography, and the partition pattern is baked to form a partition. This is achieved by a manufacturing method.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The photosensitive paste of the present invention comprises
It consists of a photosensitive paste containing (a) an ultraviolet absorber, (b) an antioxidant, (c) inorganic fine particles, and (d) a photosensitive compound, and is baked after pattern formation using photolithography. To form an inorganic pattern.

In the present invention, the ultraviolet absorber is 300
Absorbs a wavelength of about 400 nm and emits the absorbed light energy as inactive radiation (heat energy). Usually, exposure used for the photolithography technique is performed by g-line (436 nm) and h-line (405
nm) and i-line (365 nm), but the h-line and i-line have too large absorption by the photosensitive compound (photopolymerization initiator or sensitizer), and only the surface layer is exposed. And the lower layer is insufficiently cured. By adding an ultraviolet absorber to the paste, the light having a wavelength near the h-line and the i-line is absorbed, thereby increasing the transmittance of the g-line and sufficiently curing the photosensitive paste to the lower layer. it can.

The ultraviolet absorber is particularly effective if it has excellent absorbance at wavelengths near the h-line and the i-line. Specific examples include benzophenone-based compounds, cyanoacrylate-based compounds, salicylic acid-based compounds, and benzotriazole-based compounds. Compounds, indole compounds, inorganic fine metal oxide particles, and the like. Of these, benzophenone-based compounds, cyanoacrylate-based compounds, benzotriazole-based compounds, and indole-based compounds are particularly effective. Specific examples of these include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone,
2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5-sulfobenzophenone, 2-hydroxy- 4-methoxy-2'-carboxybenzophenone, 2
-Hydroxy-4-methoxy-5-sulfobenzophenone trihydrate, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, 2,2 ', 4,4'-tetrahydroxy Benzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 2-hydroxy-4- (2-hydroxy-3-methacryloxy) propoxybenzophenone, 2- (2'-hydroxy-5'-methylphenyl)
Benzotriazole, 2- (2′-hydroxy-3 ′,
5′-di-t-butylphenyl) benzotriazole,
2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2-
(2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2′-
(Hydroxy-4′-n-octoxyphenyl) benzotriazole, 2-ethylhexyl-2-cyano-3,3
-Diphenyl acrylate, 2-ethyl-2-cyano-
3,3-diphenyl acrylate, BONASORB UA-3901 (manufactured by Orient Chemical Co., Ltd.) which is an indole-based absorbent, BONASORB UA-3902 (manufactured by Orient Chemical Co., Ltd.), and SOM-2-0008 (manufactured by Orient Chemical Co., Ltd.). Are not limited to these.
Further, a methacryl group or the like may be introduced into the skeleton of these ultraviolet absorbers and used as a reaction type. In the present invention, one or more of these can be used.

It is necessary to pay attention to the ultraviolet absorber, since the transmission limit wavelength and the wavelength gradient width of the photosensitive paste film change depending on the amount of the ultraviolet absorber added. The transmission limit wavelength and wavelength slope width are
It is determined as follows according to JIS B7113. Film thickness 5
A wavelength at which the transmittance of the photosensitive paste film at 0 μm is 72% or more is a high transmission region, a wavelength corresponding to the limit is a transmission limit wavelength, and a wavelength at which the transmittance of the photosensitive paste film at a film thickness of 50 μm is 5% or less. A region is defined as an absorption region, and a wavelength corresponding to the limit is defined as an absorption limit wavelength. The interval between the transmission limit wavelength and the absorption limit wavelength is defined as the wavelength gradient width, and the wavelength corresponding to the middle point of the wavelength gradient width is defined as the transmission limit wavelength. The transmission limit wavelength and the wavelength gradient width can be measured using a general spectrophotometer.

The transmission limit wavelength is preferably 400 nm or more. More preferably, 400 nm or more and 436 n
m or less. When the transmission limit wavelength is in this range, the effect of selecting and absorbing wavelengths near the h-line and the i-line of the present invention is increased. Further, when the transmission limit wavelength is in this range and the wavelength gradient width is 50 nm or less, the transmittance at only the wavelength near the g-line can be increased, which is more preferable.

The amount of the ultraviolet absorber added is 0.001 to 10% by weight in the paste, more preferably 0.005 to 10% by weight.
５5%. Beyond these ranges, the transmission limit wavelength and the wavelength gradient range change, the absorption capacity of h-line and i-line becomes insufficient, the transmittance of g-line decreases, and the sensitivity of the photosensitive paste decreases. It costs.

The antioxidant in the present invention has one of a radical chain inhibiting action, a triplet eliminating action, and a hydroperoxide decomposing action.

Since the photosensitive paste contains many inorganic fine particle components in a dispersed state, light scattering inside the paste due to exposure light is unavoidable. ) Is easy to occur. The walls of the pattern are desirably vertically cut and rectangular. Ideally, it is dissolved in the developer below a certain exposure amount, and insoluble in the developer above it. In other words, even when cured at a low exposure amount due to light scattering, it is dissolved in a developing solution, the thickening of the pattern shape and filling between the patterns are eliminated, and the range of resolution can be increased even when the exposure amount is increased.

The present inventors have also studied a technique for using an organic dye as an ultraviolet absorber to absorb the scattered light to eliminate the thickening of the pattern shape and the burying between the patterns. However, since the organic dye has an absorption peak in a wavelength region longer than 400 nm, the effect of selecting and absorbing the above-described wavelength is small, and the sensitivity of the photosensitive paste is easily reduced.

In the present invention, as described above, light is absorbed by selecting a wavelength, and an antioxidant is further added to the photosensitive paste, so that the antioxidant captures radicals or is excited. By returning the energy state of the photopolymerization initiator and the sensitizer to the ground state, an extra light reaction due to scattered light is suppressed, and a sudden light reaction occurs at an exposure amount that cannot be suppressed by the antioxidant, The contrast between dissolution and insolubility in the developer can be increased.

Specifically, p-benzoquinone, naphthoquinone, para-xyloquinone, para-toluquinone, 2,6
-Dichloroquinone, 2,5-diacetoxy-p-benzoquinone, 2,5-dicaproxy-p-benzoquinone, hydroquinone, pt-butylcatechol, 2,5-dibutylhydroquinone, mono-t-butylhydroquinone,
2,5-di-t-amylhydroquinone, di-t-butyl paracresol, hydroquinone monomethyl ether,
α-naphthol, hydrazine hydrochloride, trimethylbenzylammonium chloride, trimethylbenzylammonium oxalate, phenyl-β-naphthylamine, parabenzylaminophenol, di-β-naphthylparaphenylenediamine, dinitrobenzene, trinitrobenzene, picric acid, quinone Dioxime, cyclohexanone oxime, pyrogallol, tannic acid, triethylamine hydrochloride, dimethylaniline hydrochloride, cuperone,
(2,2′-thiobis (4-t-octylphenolate) -2-ethylhexylaminonickel- (II),
4,4'-thiobis- (3-methyl-6-t-butylphenol), 2,2'-methylenebis- (4-methyl-
6-t-butylphenol), 2,2'-thiobis-
(4-methyl-6-t-butylphenol), triethylene glycol-bis [3- (t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6
-Hexanediol-bis [(3,5-di-t-butyl-4-hydroxyphenyl) propionate] and the like, but are not limited thereto. In the present invention, one or two of these can be used.

The amount of the antioxidant to be added is 0.1% in the paste.
01 to 30% by weight, more preferably 0.05 to 20%
Range. When the amount is less than these ranges, it is difficult to form a contrast of dissolution or insolubility in the developer, and when the amount is more than these ranges, the sensitivity of the photosensitive paste is reduced, and a large amount of exposure is required, or the degree of polymerization is reduced. As a result, the pattern shape cannot be maintained.

The inorganic fine particles in the present invention are fine particles of glass or ceramics, and are particularly useful when glass powder is used.

As the glass powder, the glass transition point 430
By containing 50% by weight or more of glass powder having a glass softening point of 470 to 580 ° C. in a paste at 50 to 500 ° C., pattern processing can be performed on a substrate used for a normal display.

It has such a glass transition point and a glass softening point, and the refractive index of the glass fine particles is 1.5 to 1.6.
By mixing the metal oxide component so as to be 5, the refractive index of the organic component can be matched, and high-precision pattern processing by suppressing light scattering becomes possible. For example, silicon oxide: 22, aluminum oxide: 23, boron oxide: 3
Glass powder composed of 3, lithium oxide: 9, magnesium oxide: 7, barium oxide: 4, and zinc oxide 2 (% by weight) has a glass transition point of 490 ° C and a glass softening point of 52.
Refractive index at 8 ° C. and g-line wavelength (436 nm):
1.59, which satisfies the conditions for use as the inorganic fine particles of the present invention.

The glass powder preferable as the photosensitive paste of the present invention has the following composition.

Lithium oxide: 3 to 10% by weight Silicon oxide: 10 to 30% by weight Boron oxide: 20 to 40% by weight Barium oxide: 2 to 15% by weight Aluminum oxide: 10 to 25% by weight Lithium oxide: 3 to 10% by weight By using a glass powder containing 0.1% by weight, not only the control of the thermal softening temperature and the thermal expansion coefficient becomes easy, but also the average refractive index of the glass can be lowered, so that the refractive index difference with the organic component can be easily reduced. Become. The addition amount of the alkali metal oxide is preferably 10% by weight or less, more preferably 8% by weight or less, in order to improve the stability of the paste.

In the above composition, sodium oxide or potassium oxide may be used in place of lithium oxide, but lithium oxide is preferred from the viewpoint of paste stability.
In the case of using potassium oxide, there is an advantage that the refractive index can be controlled with a relatively small amount of addition. Therefore, among the alkali metal oxides, addition of lithium oxide and potassium oxide is effective. In that case, alkali metal oxides should be 3
It is preferable to use glass powder containing from 10 to 10% by weight.

It is preferable that silicon oxide is blended in the range of 10 to 30% by weight, and if it is less than 10% by weight, the denseness, strength and stability of the glass layer are reduced, and the thermal expansion coefficient is out of a desired value. , A mismatch with a glass substrate is likely to occur. Further, by setting the content to 30% by weight or less, there is an advantage that the thermal softening point is lowered and baking on a glass substrate becomes possible.

It is preferable that boron oxide is blended in the range of 20 to 40% by weight. If it exceeds 40% by weight, the stability of the glass will be reduced. Boron oxide is glass powder of 800 to 12
Since it is melted at a temperature around 00 ° C and the baking temperature of the glass paste is high even when silicon oxide is large, it does not impair the electrical, mechanical and thermal properties such as electrical insulation, strength, coefficient of thermal expansion and denseness of the insulating layer. To control the baking temperature in the range of 540 to 610 ° C. If it is less than 20% by weight, the strength of the insulating layer is reduced, and the stability of the glass is reduced.

The barium oxide is preferably blended in the range of 2 to 15% by weight. If it is less than 2% by weight, it is difficult to control the glass baking temperature and the electrical insulation.
On the other hand, if the content exceeds 15% by weight, the stability and the denseness of the glass layer decrease.

It is preferable that aluminum oxide is blended in the range of 10 to 25% by weight. Aluminum oxide is added to increase the strain point of the glass. If it is less than 10% by weight, the strength of the glass layer is reduced. If it exceeds 25% by weight, the heat resistance temperature of the glass becomes too high, and it is difficult to bake the glass on the glass substrate. Further, it becomes difficult to obtain a dense insulating layer at a temperature of 600 ° C. or lower.

It is preferable that zinc oxide is blended in the range of 1.5 to 10% by weight. If it is less than 1.5% by weight, there is no effect on improving the denseness of the insulating layer. If it exceeds 10% by weight, the temperature for baking on the glass substrate becomes too low to control, and the insulation resistance is undesirably low.

It is preferable that calcium oxide is added in the range of 2 to 10% by weight. Added to help melt the glass and control the coefficient of thermal expansion. If it is less than 2% by weight, the strain point becomes too low.

It is preferable that magnesium oxide is blended in the range of 1 to 10% by weight. Magnesium oxide is added to facilitate melting of the glass and to control the coefficient of thermal expansion. If it exceeds 10% by weight, the glass tends to be devitrified, which is not good.

It is preferable that the glass powder does not contain sodium oxide, potassium oxide, yttrium oxide, etc., which deteriorate the discharge characteristics of the plasma. Even when it is contained, it is at most 5% by weight.

The glass powder may contain titanium oxide, zirconium oxide and the like, but the amount is preferably less than 2% by weight. Zirconium oxide is effective in controlling the softening point, transition point and electrical insulation of glass.

As a method for producing glass powder, for example, raw materials such as lithium oxide, silicon oxide, aluminum oxide,
Boron oxide, barium oxide, zinc oxide, and the like are mixed so as to have a predetermined composition, melted at 900 to 1200 ° C., quenched, glass frit, and pulverized.
Make a fine powder of μm. As a raw material, a high-purity carbonate, oxide, hydroxide, or the like can be used. In addition, depending on the type and composition of the glass powder, ultra-high purity alkoxide or organometallic raw material of 99.99% or more is used. It is preferable because a high-strength insulating layer having few pores can be obtained.

The particle diameter of the glass powder used in the above is selected in consideration of the shape of the pattern to be produced, and the powder has a particle diameter of 50% by weight (average particle diameter) of 2 to 2.
It is necessary that the thickness be 3.5 μm and the top size be 15 μm or less. Further, when the 10% by weight particle size is 0.6 to 1.5.
μm, 90% by weight particle size 4-8 μm, specific surface area 1.5
It preferably has a density of up to ^2.5 m ² / g. More preferably, the average particle size is 2.5 to 3.5 μm, and the specific surface area is 1.
7 to 2.4 m ² / g. Within this range, light is sufficiently transmitted at the time of ultraviolet exposure, and a partition pattern with a small line width difference between the upper and lower portions can be obtained. If the average particle size is 2.0 μm or less and the specific surface area exceeds 2.5 m ² / g, the powder becomes too fine and light is scattered at the time of exposure to cure the unexposed portion, which is not preferable.

The organic components used in the present invention include:
It refers to an organic component (a portion obtained by removing the inorganic component from the paste) in the photosensitive paste, and preferably contains 5 to 50% by weight of the paste.

The organic component is a photosensitive component selected from at least one of a photosensitive monomer, a photosensitive oligomer, and a photosensitive polymer, and a binder, the ultraviolet absorber and the antioxidant, an organic dye, a photopolymerization initiator, It is constituted by adding an additive component such as a sensitizer, a sensitization aid, a plasticizer, a thickener, an organic solvent, a dispersant, and an organic or inorganic suspending agent as required.

As the photosensitive monomer, a compound having an active carbon-carbon double bond is often used. As the functional group, monofunctional and polyfunctional compounds having a vinyl group, an allyl group, an acrylate group, a methacrylate group, and an acrylamide group can be applied. The present invention is characterized in that a polyfunctional acrylate compound and / or a methacrylate compound are contained in an organic component in an amount of 10 to 80% by weight. Since various kinds of compounds have been developed for the polyfunctional compound having an acrylate or methacrylate functional group, it is possible to select the compound in consideration of reactivity, refractive index, and the like.

As a method of controlling the refractive index of the organic component contained in the photosensitive paste, a method of controlling the refractive index of the photosensitive monomer is simple. In particular, the refractive index is 1.55-1.
By using the photosensitive monomer of No. 8, the refractive index of the organic component can be increased.

As the photosensitive monomer to be used, it is effective to use an acrylate monomer or a methacrylate monomer containing an aromatic ring such as a benzene ring or a naphthalene ring or a sulfur atom to increase the refractive index. In particular, in order to increase the crosslink density at the time of curing by photoreaction and to improve the pattern formability, it is effective to use a polyfunctional acrylate monomer or methacrylate monomer to increase the refractive index.

Specifically, pentaerythritol triacrylate or tetraacrylate, bisphenol A di (meth) acrylate, bisphenol A-ethylene oxide adduct di (meth) acrylate, bisphenol A-propylene oxide adduct di (meth) acrylate ) Acrylates, thiophenol (meth) acrylates, benzylmercaptan (meth) acrylates or compounds in which 1 to 5 hydrogen atoms in their aromatic rings have been replaced by chlorine or bromine atoms can be used.

As the monomer containing a sulfur atom in the molecule, a monomer having a thiol (meth) acrylate group or a monomer having a phenyl sulfide structure can be used. Various monomers can be used in combination with these monomers for improving the refractive index.

As an organic component constituting the photosensitive paste, an oligomer or a polymer is used as a component that plays a role in improving the physical properties of a cured product formed by photoreaction and adjusting the viscosity of the paste. The oligomer or polymer is obtained by polymerization or copolymerization of a component selected from compounds having a carbon-carbon double bond.

As a monomer to be copolymerized, developability with an aqueous alkali solution after exposure can be improved by copolymerizing an unsaturated acid such as an unsaturated carboxylic acid.
Specific examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof.

The acid value (A) of the polymer or oligomer having an acidic group such as a carboxyl group in the side chain thus obtained is obtained.
V) is preferably in the range of 50 to 180, more preferably 70 to 140. When the acid value exceeds 180, the allowable development width becomes narrow. Further, when the acid value is 50 or less, the solubility of the unexposed portion in the developing solution is reduced, so that the developing solution concentration is increased, peeling occurs up to the exposed portion, and it is difficult to obtain a high-definition pattern. Become.

By adding a photoreactive group to a side chain or a molecular terminal to the above-described polymer or oligomer, it can be used as a photosensitive polymer or a photosensitive oligomer having photosensitivity.

Preferred photoreactive groups are those having an ethylenically unsaturated group. As the ethylenically unsaturated group,
Examples include a vinyl group, an allyl group, an acryl group, and a methacryl group.

A method for adding such a side chain to an oligomer or a polymer is based on a method in which an ethylenically unsaturated compound having a glycidyl group or an isocyanate group or an acrylic acid is added to a mercapto group, an amino group, a hydroxyl group or a carboxyl group in the polymer. There is a method in which chloride, methacrylic chloride or allyl chloride is added to make an addition reaction.

Examples of the ethylenically unsaturated compound having a glycidyl group include glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, glycidyl ethyl acrylate, crotonyl glycidyl ether, glycidyl ether crotonic acid, glycidyl ether isocrotonic acid, and the like. .

Examples of the ethylenically unsaturated compound having an isocyanate group include (meth) acryloyl isocyanate and (meth) acryloylethyl isocyanate.

The ethylenically unsaturated compound having a glycidyl group or an isocyanate group, acrylic acid chloride, methacrylic acid chloride or allyl chloride is used in an amount of 0.05 to 0.05 to the mercapto group, amino group, hydroxyl group and carboxyl group in the polymer. It is preferable to add 1 molar equivalent.

The present invention is characterized in that an organic component contains 10 to 90% by weight of an oligomer or a polymer having a carboxyl group and an unsaturated double bond in the molecule and having a weight average molecular weight of 500 to 100,000. .

When a binder component is required, polyvinyl alcohol, polyvinyl butyral, methacrylate polymer, acrylate polymer, acrylate-methacrylate copolymer, butyl methacrylate resin, etc. may be used as the polymer. Can be. It is also effective to increase the refractive index of the binder component to increase the refractive index of the photosensitive organic component.

The organic component of the photosensitive paste of the present invention contains a photosensitive monomer, a photosensitive oligomer, a photosensitive polymer, or a binder, but none of these components has an energy absorbing ability for actinic rays. It is necessary to add a photopolymerization initiator and a sensitizer in order to start the reaction.

The pattern formation by the photosensitive paste is to polymerize and crosslink the photosensitive components (monomers, oligomers, and polymers) in the exposed portions to make them insoluble in a solvent. Is a radical polymerizable, and its photopolymerization initiator is selected from those generating radical species. In particular, those which generate radical species by light of 400 nm or more are preferable.
In combination with a sensitizer, a photopolymerization initiator that generates a radical species with the following light absorbs light of 400 nm or more,
Care must be taken because radical species may be generated.

Specific examples of the photopolymerization initiator include benzophenone, methyl o-benzoylbenzoate, 4,4-bis (dimethylamino) benzophenone, 4,4-bis (diethylamino) benzophenone, and 4,4-dichlorobenzophenone. , 4-benzoyl-4-methylphenyl ketone, dibenzyl ketone, fluorenone, 2,3-diethoxyacetophenone, 2,2-dimethoxy-2-phenyl-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone , Pt-butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl, benzyldimethylketal, benzylmethoxyethylacetal, benzo Emissions, benzoin methyl ether, benzoin butyl ether, anthraquinone, 2-
t-butylanthraquinone, 2-aminoanthraquinone, β-chloroanthraquinone, anthrone, benzanthrone, dibensuberone, methyleneanthrone, 4
-Azidobenzalacetophenone, 2,6-bis (p-
(Azidobenzylidene) cyclohexane, 2,6-bis (p-azidobenzylidene) -4-methylcyclohexanone, 2-phenyl-1,2-butadione-2- (o-
Methoxycarbonyl) oxime, 1-phenylpropanedione-2- (o-ethoxycarbonyl) oxime,
1,3-diphenylpropanetrione-2- (o-ethoxycarbonyl) oxime, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, naphthalenesulfonyl chloride, quinoline sulfonyl chloride, N-phenyl Thioacridone, 4,
Photoreducing dyes such as 4-azobisisobutyronitrile, diphenyl disulfide, benzothiazole disulfide, triphenylphosphine, camphorquinone, carbon tetrabromide, tribromophenyl sulfone, benzoyl peroxide and eosin, methylene blue, and ascorbic acid And a combination of reducing agents such as triethanolamine.

In the present invention, one or more of these can be used. The photopolymerization initiator is added in a range of 0.05 to 10% by weight, more preferably 0.1 to 10% by weight, based on the photosensitive component. If the amount of the polymerization initiator is too small, the photosensitivity becomes poor, and if the amount of the photopolymerization initiator is too large, the residual ratio of the exposed portion may be reduced.

By using a sensitizer together with the photopolymerization initiator, the sensitivity can be improved and the wavelength range effective for the reaction can be extended.

Specific examples of the sensitizer include 2,4-diethylthioxanthone, isopropylthioxanthone,
3-bis (4-diethylaminobenzal) cyclopentanone, 2,6-bis (4-dimethylaminobenzal) cyclohexanone, 2,6-bis (4-dimethylaminobenzal) -4-methylcyclohexanone, Michler's ketone, 4,4-bis (diethylamino) benzophenone,
4,4-bis (dimethylamino) chalcone, 4,4-bis (diethylamino) chalcone, p-dimethylaminocinnamylidene indanone, p-dimethylaminobenzylidene indanone, 2- (p-dimethylaminophenylvinylene) iso Naphthothiazole, 1,3-bis (4-dimethylaminophenylvinylene) isonaphthothiazole, 1,3-bis (4-dimethylaminobenzal) acetone, 1,3-carbonylbis (4-diethylaminobenzal) acetone, 3,3-carbonylbis (7-diethylaminocoumarin), N-phenyl-N-ethylethanolamine, N-phenylethanolamine, N-tolyldiethanolamine, isoamyl dimethylaminobenzoate, isoamyl diethylaminobenzoate, 3-phenyl-5 -Benzoi Thiotetrazole, such as 1-phenyl-5-ethoxycarbonyl-thiotetrazole the like.

In the present invention, one or more of these can be used. Some sensitizers can also be used as photopolymerization initiators. When a sensitizer is added to the photosensitive paste of the present invention, the amount is usually 0.05 to 10% by weight, more preferably 0.1 to 10% by weight, based on the photosensitive component. If the amount of the sensitizer is too small, the effect of improving the photosensitivity is not exhibited, and if the amount of the sensitizer is too large, the residual ratio of the exposed portion may be reduced.

In the present invention, an organic dye can be added as a mark for exposure and development. By adding a dye and coloring, visibility is improved, and it becomes easy to distinguish a portion where the paste remains and a portion where the paste has been removed during development.
The organic dye is not particularly limited, but preferably does not remain in the insulating film after firing. Specifically, azo dyes, anthraquinone dyes, indigoid dyes,
Phthalocyanine dyes, carbonium dyes, quinone imine dyes, methine dyes, quinoline dyes, nitro dyes, nitroso dyes, benzoquinone dyes, naphthoquinone dyes, phthalimide dyes, and perinone dyes can be used. In particular, it is preferable to select a material that absorbs light having wavelengths near the h-line and the i-line, for example, a carbonium-based dye such as basic blue, because the effects of the present invention can be more easily achieved. The added amount of the organic dye is preferably 0.001 to 1% by weight.

An organic solvent is used to adjust the viscosity when applying the photosensitive paste to the substrate according to the application method. Examples of the organic solvent used at this time include methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyl lactone, and propylene carbonate. For example, propylene glycol monomethyl ether acetate, bromobenzene, chlorobenzene, dibromobenzene, dichlorobenzene, bromobenzoic acid, chlorobenzoic acid, and an organic solvent mixture containing at least one of these are used.

The photosensitive paste is usually made of an ultraviolet absorber,
Antioxidants, inorganic fine particles, photosensitive organic components, organic dyes,
Various components such as a dispersant, a light absorbing agent, and a solvent are blended so as to have a predetermined composition, and then uniformly mixed and dispersed with a three-roller or a kneader to produce.

The viscosity of the paste is appropriately adjusted by the addition ratio of inorganic fine particles, a thickener, an organic solvent, a plasticizer, a suspending agent and the like.
(Centipoise). For example, when the coating on the substrate is performed by the spin coating method, 2000 to 5000 cps
Is preferred. Coated once by screen printing method to obtain a film thickness of 10
In order to obtain ２０20 μm, 50,000 to 200,000 cps is preferable. When using a blade coater method, a die coater method, or the like, 10,000 to 50,000 cps is preferable.

An example in which pattern processing is performed using a photosensitive paste will be described, but the present invention is not limited to this.

On the substrate, the photosensitive paste is applied entirely or partially. As a coating method, a method such as a screen printing method, a bar coater, a roll coater, a die coater, or a blade coater can be used. The coating thickness can be adjusted by selecting the number of coatings, the screen mesh, and the viscosity of the paste.

Here, when applying the paste on the substrate,
Surface treatment of the substrate can be performed to enhance the adhesion between the substrate and the coating film. Examples of the surface treatment liquid include silane coupling agents such as vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, tris (2-methoxyethoxy) vinylsilane, γ-glycidoxypropyltrimethoxysilane, γ- (methacrylic acid). Roxypropyl) trimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and the like, or an organic metal such as , Organic titanium,
Organic aluminum, organic zirconium and the like. A silane coupling agent or an organic metal diluted with an organic solvent such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl alcohol, ethyl alcohol, propyl alcohol, or butyl alcohol to a concentration of 0.1 to 5% is used. Used.
Next, this surface treatment liquid is uniformly applied on a substrate by a spinner or the like, and then dried at 80 to 140 ° C. for 10 to 60 minutes to perform surface treatment.

After application, exposure is performed using an exposure device. As an exposure apparatus, a proximity exposure machine or the like can be used. Also, when performing large area exposure,
After applying the photosensitive paste on the substrate, by performing exposure while transporting, with an exposure machine with a small exposure area,
A large area can be exposed.

After the exposure, development is performed by utilizing the difference in solubility between the exposed portion and the non-exposed portion in the developing solution.
It is performed by a dipping method, a spray method, or a brush method. An organic solvent in which an organic component in the photosensitive paste can be dissolved is used as the developer. In addition, water may be added to the organic solvent as long as its solvent power is not lost. When a compound having an acidic group such as a carboxyl group is present in the photosensitive paste, development can be performed with an aqueous alkali solution. As the alkaline aqueous solution, sodium hydroxide, sodium carbonate, calcium hydroxide aqueous solution and the like can be used, but it is preferable to use an organic alkaline aqueous solution since an alkaline component can be easily removed during firing.

As the organic alkali, a general amine compound can be used. Specific examples include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine, diethanolamine and the like.

The concentration of the aqueous alkali solution is usually 0.05 to 5
%, More preferably 0.1 to 1% by weight. If the alkali concentration is too low, the soluble portion is not removed, and if the alkali concentration is too high, the pattern portion may be peeled off and the non-soluble portion may be corroded, which is not good. The development temperature during development is preferably from 20 to 50 ° C. from the viewpoint of process control.

Next, firing is performed in a firing furnace. The firing atmosphere and temperature vary depending on the type of paste or substrate, but firing is performed in an atmosphere such as air, nitrogen, or hydrogen. As the firing furnace, a batch-type firing furnace or a belt-type continuous firing furnace can be used.

The firing is performed at a temperature of 400 to 1000 ° C. When processing a pattern on a glass substrate, 520 to 610
The firing is carried out at a temperature of 10 ° C. for 10 to 60 minutes.

[0076]

The present invention will be described below in more detail with reference to examples. However, the present invention is not limited to this. The concentration (%) in the examples is% by weight.

Example 1 The photosensitive paste was a photosensitive polymer (styrene / acrylic acid copolymer, weight composition ratio 60/40, weight average molecular weight 1).
000): 15 parts by weight, photosensitive monomer (dipentaerythritol hexaacrylate): 15 parts by weight, and a photopolymerization initiator (2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) ) Butanone-1): 6.0 parts by weight, sensitizer (2,4-diethylthioxanthone): 1.2 parts by weight, antioxidant (1,6-hexanediol-bis [(3,5-di- t-butyl-4
-Hydroxyphenyl) propionate]): 3.0 parts by weight, ultraviolet absorber (2-ethylhexyl-2-cyano-3,3-diphenylacrylate, maximum absorption wavelength: 3)
20 nm): 0.5 parts by weight and 0.01 parts by weight of an organic dye (Basic Blue 26, maximum absorption wavelength: 592 nm) are dissolved while heating to 50 ° C., and then 70 parts by weight of the following inorganic fine particles are dissolved. It was prepared by the procedure of adding and kneading with a kneader. The viscosity was adjusted by the amount of γ-butyrolactone, but the amount of the solvent in the paste was adjusted to 10 to 40%. The transmission limit wavelength of the paste at a film thickness of 50 μm was 420 nm, and the wavelength gradient width was 30 nm.

The composition of the inorganic fine particles is Li ₂ O:
_{9%, SiO 2: 22%} , Al 2 O 3: 23%, B 2 O 3:
Glass fine particles of 33%, BaO: 4%, ZnO: 2%, and MgO: 7% were used. The glass particles have an average refractive index of 1.586, a glass transition point and a softening point of 4 respectively.
76 ° C., 519 ° C., the average particle size is 2.6 μm.

A photosensitive paste was uniformly applied on a soda glass substrate by screen printing. Coating and drying were repeated several times or more in order to avoid pinholes or the like on the coating film, and coating was performed so that the dry thickness became 180 μm. Drying was performed at 80 ° C. for 10 minutes. Then, it dried at 80 degreeC for 60 minutes.

A photomask (striped pattern,
Exposure was performed through a pattern pitch of 130 μm and a line width of 20 μm). Exposure was performed with an ultra-high pressure mercury lamp having an output of 50 mW / cm ² to perform an ultraviolet exposure of 1.0 J / cm ² . At this time, in order to prevent the mask from being contaminated, a gap of 100 μm was provided between the mask and the coating film surface. Thereafter, a 0.3% by weight aqueous solution of monoethanolamine kept at 35 ° C. is developed by spraying with a shower for 180 seconds, and then washed with water using a shower spray to remove a space portion that has not been photocured and glass. A stripe-shaped partition pattern was formed on the substrate.

The glass substrate after the processing of the partition pattern was dried at 80 ° C. for 15 minutes, and then baked at 560 ° C. for 15 minutes to form a partition. The firing causes a shrinkage of about 30%.

The shape of the pattern formed by exposure and development before firing was observed with an electron microscope.
m, the line width at the top of the pattern was 28 μm, the line width at the center of the pattern was 37 μm, and the line width at the bottom of the pattern was 48 μm. After baking, the obtained partition walls had a good height of 122 μm, a line width of 18 μm at the top of the pattern, a line width of 24 μm at the middle of the pattern, and a line width of 31 μm at the bottom of the pattern. The same pattern shape was obtained at an exposure amount of 1.0 J / cm ² ± 20%.

Example 2 As an ultraviolet absorber, BO which is an indole-based absorber was used.
NASORB UA-3901 (Orient Chemical Co., Ltd.)
(Absorptive maximum wavelength: 395 nm) was performed in the same manner as in Example 1. The transmission limit wavelength of the paste at a film thickness of 50 μm was 430 nm, and the wavelength gradient width was 25 nm.
The exposure amount was 1.2 J / cm ² . The obtained pattern cross-section has a height of 181 μm and a line width of 30 at the top of the pattern.
μm, the line width at the center of the pattern was 40 μm, and the line width at the bottom of the pattern was 51 μm. After firing, the resulting partitions have a height of 11
8 μm, the line width at the upper part of the pattern was 19 μm, the line width at the middle part of the pattern was 26 μm, and the line width at the lower part of the pattern was 33 μm. The exposure amount is 1.2 J / cm ² ±
The same pattern shape was obtained even when changed by 20%.

Example 3 The same procedure as in Example 1 was carried out except that 5.2 parts by weight of camphorquinone was used as a photopolymerization initiator. The transmission limit wavelength of the paste at a film thickness of 50 μm was 420 nm, and the wavelength gradient width was 30 nm. The exposure amount was 3.4 J / cm ² . The obtained pattern cross-section has a height of 180 μm, a line width of 26 μm above the pattern, and a line width of 38 μm in the middle of the pattern.
m, and the line width under the pattern was 46 μm. After baking, the obtained partition had a height of 119 μm and a line width of 18 at the top of the pattern.
μm, the line width at the center of the pattern was 24 μm, and the line width at the bottom of the pattern was 32 μm. The same pattern shape was obtained even when the exposure amount was changed by 3.4 J / cm ² ± 15%.

Comparative Example The same operation as in Example 1 was performed except that the amount of exposure was changed without using an ultraviolet absorber. The transmission limit wavelength of the paste at a film thickness of 50 μm was 380 nm, and the wavelength gradient width was 60 nm. The pattern cross-sectional shape obtained at an exposure dose of 0.4 J / cm ² has a height of 180 μm, a line width of 46 μm above the pattern,
Line width 36 μm in the middle of the pattern, line width 27 in the lower part of the pattern
At μm, the pattern wandered. Further, when the developing time was added for 30 seconds, the pattern was separated from the substrate. The cross-sectional shape of the pattern obtained at an exposure dose of 0.5 J / cm ² was a height of 180 μm, a line width of the upper part of the pattern was 48 μm, a line width of the middle part of the pattern was 42 μm, and the lower part of the pattern was formed by connecting adjacent patterns. Was. Further, although the developing time was added for 180 seconds, the pattern cross-sectional shape did not change.

[0086]

According to the photosensitive paste of the present invention, 3
By adding an ultraviolet absorber having an absorption maximum in a wavelength region of 00 to 400 nm, a high-aspect ratio and high-precision pattern processing can be performed without modifying the exposure apparatus, and the pattern shape becomes favorable. Partitions formed after firing can be made more excellent. As a result, it becomes possible to process a thick film such as a display or a circuit material, and to perform high-precision pattern processing, thereby improving the definition and simplifying the process. In particular, a highly accurate partition wall of a plasma display panel can be formed easily.

Claims (12)

[Claims] (1) an ultraviolet absorber having an absorption maximum in a wavelength region of 300 to 400 nm, (b) an antioxidant, and (c)
A photosensitive paste comprising: inorganic fine particles; and (d) a photosensitive compound. 2. The method according to claim 1, wherein the ultraviolet absorber is a benzophenone compound.
The photosensitive paste according to claim 1, wherein the photosensitive paste is selected from a cyanoacrylate compound, a benzotriazole compound, and an indole compound. 3. The photosensitive paste according to claim 1, wherein a transmission limit wavelength of the photosensitive paste film at a film thickness of 50 μm is 400 nm or more. 4. The photosensitive paste film having a thickness of 50 μm has a transmission limit wavelength of 400 nm or more and a wavelength gradient width of 50 nm or less.
A photosensitive paste according to any one of the above. 5. An antioxidant is added to the paste in an amount of 0.01 to 30.
The photosensitive paste according to any one of claims 1 to 4, wherein the photosensitive paste is contained by weight%. 6. The photosensitive material according to claim 1, wherein glass powder is used as the inorganic fine particles, and the glass powder has an average refractive index in the range of 1.5 to 1.65. paste. 7. The photosensitive paste according to claim 1, wherein a glass powder containing 3 to 10% by weight of at least one of lithium oxide, sodium oxide and potassium oxide is used. 8. The glass powder is expressed in terms of oxide as lithium oxide: 3 to 10% by weight Silicon oxide: 10 to 30% by weight Boron oxide: 20 to 40% by weight Barium oxide: 2 to 15% by weight Aluminum oxide: 10 to 10% The photosensitive paste according to claim 1, comprising 25% by weight. 9. A glass powder having a glass transition point of 430 to 50.
The photosensitive paste according to any one of claims 1 to 8, wherein the glass paste has a glass softening point of 470 to 580 ° C. 10. The photosensitive paste according to claim 1, wherein a polymer having a carboxyl group and a weight average molecular weight of 300 to 100,000 is used as the photosensitive compound. 11. The photosensitive paste according to claim 1, wherein a polymer having a weight average molecular weight of 300 to 100,000 having a carbon-carbon double bond is used as the photosensitive compound. 12. A method of applying the photosensitive paste according to claim 1 on a substrate, forming a partition pattern by photolithography, and baking the partition pattern to form a partition. Manufacturing method of a plasma display.