JPH10171117A - Photosensitive paste and production of plasma display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease reflection and scattering on the interface of an inorg. component and to obtain a pattern of high aspect ratio and high accuracy by incorporating photoreactive monomers having a specified range of refractive index into a photoreactive compd. SOLUTION: The photosensitive paste contains inorg. fine particles and an org. component containing a photoreactive compd. as the essential components, and the photoreactive compd. contains photoreactive monomers having 1.55 to 1.8 refractive index. It is preferable that 60wt.% or more of the inorg. fine particles are glass fine particles. As for the glass fine particles, glass fine particles containing at least one of bismuth oxide, lead oxide and lithium oxide by 5 to 80wt.% are preferably used. The glass compsn. containing bismuth oxide consists of 5 to 50 pts.wt. Bi2 O3 , 3 to 60 pts.wt. SiO2 and 5 to 40 pts.wt. B2 O3 . To control the refractive index of the org. component in the photosensitive paste, it is preferable to control the refractive index of the photosensitive monomers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a novel photosensitive paste. The photosensitive paste of the present invention is used for pattern processing of displays such as plasma displays and pattern processing of circuit materials and the like.

[0002]

2. Description of the Related Art In recent years, miniaturization and high definition of circuit materials and displays have been progressing, and accordingly, there has been a demand for an improvement in pattern processing technology. In particular, for forming a green sheet used for a CPU or the like of a computer or a partition wall of a plasma display panel, a material which has high accuracy and is capable of pattern processing with a high aspect ratio is desired.

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 highly accurate pattern 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 5342929/1993 propose a method of forming a photosensitive paste using a photolithography technique. However, since the sensitivity and resolution of the photosensitive paste are low, high aspect ratio and high definition partition walls cannot be obtained. For example, when patterning a material having a thickness exceeding 80 μm, a plurality of processing steps (screen Printing / exposure / development).

In Japanese Patent Application Laid-Open No. 2-165538, after a photosensitive paste is coated on transfer paper,
Japanese Patent Application Laid-Open No. 3-57138 proposes a method of transferring a transfer film onto a glass substrate to form partitions, in which grooves of a photoresist layer are filled with a dielectric paste to form partitions. . Also, JP-A-4-109
No. 536 proposes a method of forming a partition using a photosensitive organic film. However, these methods have a problem that the number of steps is increased because a transfer film, a photoresist, or an organic film is required. Further, a partition having a high definition and a high aspect ratio has not been obtained.

[0006]

The inventors of the present invention have made intensive studies on a photosensitive paste free from the above-mentioned disadvantages, and as a result, have arrived at the following invention. In particular, it is an object of the present invention to provide a photosensitive paste that enables high-aspect-ratio and high-accuracy pattern processing.

[0007]

SUMMARY OF THE INVENTION The present invention reduces the reflection and scattering at the interface with the inorganic component by controlling the refractive index of the organic component in the photosensitive paste, and achieves a high aspect ratio and high precision. The present invention relates to a photosensitive paste characterized by performing pattern processing.

An object of the present invention is to provide a photosensitive paste containing as an essential component an organic component containing inorganic fine particles and a photoreactive compound, wherein the photoreactive compound has a refractive index of 1.55 to 1.8. This is achieved by a photosensitive paste characterized by containing a reactive monomer.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION As the inorganic fine particles, it is preferable to use glass or ceramics.
In this case, glass fine particles are used as the inorganic fine particles.

The glass fine particles are not particularly limited, but have a glass transition temperature of 350 to 500 ° C. and a heat softening temperature of 4 ° C.
By containing 30% by weight or more of the glass fine particles at a temperature of 00 to 600 ° C. in the paste, pattern processing can be performed on a glass substrate used for a normal display.

As such glass particles, glass particles containing at least one of bismuth oxide, lead oxide and lithium oxide in an amount of 5 to 80% by weight can be used. It is preferable to use glass particles containing 5 to 50% by weight of bismuth oxide.

The glass composition containing bismuth oxide includes:
Preferable to use a glass fine particles containing Bi ₂ O ₃ 5 to 50 parts by weight component of SiO ₂ 3 to 60 parts by weight B ₂ O ₃ 5 to 40 parts by weight on an oxide basis representation, and further, the glass particles, Bi ₂ O ₃ 5 to 50 parts by weight SiO ₂ 3 to 60 parts by weight B ₂ O ₃ 5 to 40 parts by weight BaO 0 to 25 parts by weight Al ₂ O ₃ 0~ 5 parts ZnO 2 to 40 weight in terms of oxide title It has been found that an excellent pattern can be formed on a glass substrate by using glass fine particles containing a part of the components.

Although the glass powder may contain Li ₂ O, its amount is preferably not more than 60% by weight. In addition, CaO, TiO ₂ , Zr
O _{2 and the} like can be contained, but the amount is preferably 20% by weight or less. Na ₂ O, K
_The content of metal oxides such as ₂ O and Y ₂ O ₃ is preferably 5% by weight or less.

As for the composition in the glass powder, SiO ₂ is preferably blended in the range of 3 to 60% by weight, and if it is less than 3% by weight, the denseness, strength and stability of the glass layer are reduced. A mismatch between the glass substrate and the thermal expansion coefficient occurs, deviating from a desired value. Further, when the content is set to 60% by weight or less, there is an advantage that the heat softening point is lowered and baking on a glass substrate becomes possible.

By mixing B ₂ O ₃ in the range of 5 to 40% by weight, it is possible to improve electric, mechanical and thermal properties such as electric insulation, strength, coefficient of thermal expansion and denseness of the insulating layer. it can. On the other hand, if it exceeds 40% by weight, the stability of the glass is reduced.

Bi ₂ O ₃ is 5 to 80% by weight, more preferably 5 to 60% by weight, and still more preferably 5 to 50% by weight.
It is preferable to mix in the range of. When the content is less than 5% by weight, the effect of controlling the baking temperature when baking the glass paste on the glass substrate is small. If it exceeds 80% by weight, the heat-resistant temperature of the glass becomes too low and it is difficult to bake the glass on a glass substrate.

It is preferable that ZnO is blended in the range of 2 to 40% by weight. If it exceeds 40% by weight, the temperature for baking on the glass substrate becomes too low to control.
In addition, the insulation resistance is undesirably low.

The particle diameter of the glass powder used in the above is selected in consideration of the shape of the pattern to be produced, but the particle diameter of 50% by weight is preferably 0.1 to 10 μm.

Further, the present inventors have proposed that, as glass fine particles,
By using glass particles that are spherical in shape,
It has been found that patterning with a high aspect ratio is possible. By using 50% by weight or more of glass particles having a sphericity of 80% by number or more as glass particles,
Light scattering in the paste can be suppressed by reducing the glass surface area.

Further, as glass fine particles, 436 nm
It is preferable to use glass fine particles characterized by using glass fine particles having a total light transmittance of 50% or more at the above wavelength. By suppressing the scattering and absorption inside the glass fine particles, the pattern characteristics are improved.

The glass fine particles used in this case include:
Glass fine particles having a 50% by weight particle size of 1 to 7 μm, a 10% by weight particle size of 0.4 to ² μm, a 90% by weight particle size of 4 to 10 μm, and a specific surface area of 0.2 to ³ m ² / g are suitable.

The glass containing bismuth oxide, lead oxide and lithium oxide has an average refractive index of 1.56-1.80,
In most cases it will be between 1.60 and 1.80. In this case, when the average refractive index of the organic component is 1.56 or less, the difference in the refractive index between the organic component and the inorganic fine particles increases, and light scattering occurs.
Pattern formation becomes difficult.

Therefore, the inventors have found that the glass transition point is 35%.
Even when glass fine particles of 0 to 550 ° C. are used, the refractive index is set to 1.
It has been found that a photosensitive paste containing an organic component of 56 or more, more preferably 1.6 or more is effective for high-accuracy patterning with a high aspect ratio. However, when the average refractive index of the organic component is 1.8 or more, the refractive index is too high, and conversely, the light scattering becomes too large, which is not preferable.

In particular, when glass particles containing 10% by weight or more of bismuth oxide are used, the refractive index of the organic component is 1.5.
It is preferred to be 6 or more.

By setting the difference in the average refractive index between the organic component and the inorganic fine particles to be 0.05 or less, the pattern workability at the time of thick film is further improved. The difference in average refractive index is an absolute value of a value obtained by subtracting the average refractive index of an organic substance from the average refractive index of inorganic fine particles.

In the measurement of the refractive index in the present invention, it is accurate to confirm the effect by measuring the wavelength of ultraviolet light to be applied after applying the paste. In particular, 350-48
It is preferable to measure with light of an arbitrary wavelength within the range of 0 nm. Furthermore, i-line (365 nm) and h-line (40 nm)
5 nm) and g-line (436 nm).

The organic component includes a photosensitive component selected from at least one of a photosensitive monomer, a photosensitive oligomer, and a photosensitive polymer, and a binder, a photopolymerization initiator, an ultraviolet absorber, a sensitizer, and a sensitizer. Additives such as auxiliaries, polymerization inhibitors, plasticizers, thickeners, organic solvents, antioxidants, dispersants, and organic or inorganic suspending agents are also added.

As the photosensitive component, there are a photo-insolubilizing type and a photo-solubilizing type, and the photo-insolubilizing type includes: (1) a functional monomer having at least one unsaturated group or the like in a molecule. (2) those containing photosensitive compounds such as aromatic diazo compounds, aromatic azide compounds and organic halogen compounds (3) so-called diazo resins such as condensates of diazo-based amines and formaldehyde And others. Also,
Examples of the photo-soluble type include (4) a complex of a diazo compound with an inorganic salt or an organic acid, and a compound containing a quinone diazo compound. (5) a quinone diazo compound combined with an appropriate polymer binder, for example, a phenol or novolak resin. Naphthoquinone 1,2-diazido-5-sulfonic acid ester.

As the photosensitive component used in the present invention, all of the above can be used. As a method for increasing the refractive index of the photoreactive component, a photosensitive monomer having a high refractive index, a photosensitive oligomer, There is a method using at least one of the photosensitive polymers.

The simplest method of controlling the refractive index of the organic component contained in the photosensitive paste is to control the refractive index of the photosensitive monomer.

In particular, by using a photoreactive monomer having a refractive index of 1.55 to 1.8 in the organic component at 10 to 80% by weight, preferably 20 to 70% by weight, the refractive index of the organic component is increased. Can be.

As the photosensitive monomer to be used, it is effective to increase the refractive index by using a methacrylate monomer or an acrylate monomer containing an aromatic ring such as a benzene ring or a naphthalene ring or a sulfur atom.

In particular, in order to increase the crosslink density at the time of photocuring and to improve the pattern formability, it is effective to use a polyfunctional methacrylate monomer or acrylate monomer to increase the refractive index.

Specifically, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, benzyl (meth) acrylate, 1-naphthyl (meth) acrylate, 2-naphthyl (meth) acrylate, bisphenol A di (meth) acrylate Di (meth) acrylate of bisphenol A-ethylene oxide adduct, di (meth) acrylate of bisphenol A-propylene oxide adduct, 1-naphthyl (meth) acrylate, 2-naphthyl (meth) acrylate, thiophenol (meth) Acrylates, benzyl mercaptan (meth) acrylates, and compounds in which 1 to 5 hydrogen atoms in these aromatic rings have been substituted with chlorine or bromine atoms can be used.

As the monomer having 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.

Specific examples of the monomer containing phenyl sulfide include those represented by the following general formula (a). R in the structural formula represents a hydrogen atom or a methyl group.
n is 0 or 1.

[0037]

Embedded image Various kinds of photosensitive monomers can be mixed with these monomers for improving the refractive index.

The photosensitive monomer is a compound containing a carbon-carbon unsaturated bond, and specific examples thereof include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, and sec-butyl. Acrylate, sec-
Butyl acrylate, iso-butyl acrylate, te
rt-butyl acrylate, n-pentyl acrylate, allyl acrylate, benzyl acrylate, butoxyethyl acrylate, butoxytriethylene glycol acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, 2-ethylhexyl acrylate, glycerol acrylate, glycidyl acrylate Heptadecafluorodecyl acrylate, 2-hydroxyethyl acrylate, isobonyl acrylate, 2-hydroxypropyl acrylate, isodexyl acrylate, isooctyl acrylate, lauryl acrylate, 2-
Methoxyethyl acrylate, methoxyethylene glycol acrylate, methoxydiethylene glycol acrylate, octafluoropentyl acrylate, phenoxyethyl acrylate, stearyl acrylate, trifluoroethyl acrylate, allylated cyclohexyl diacrylate, 1,4-butanediol diacrylate, 1,3-butylene Glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, ditrimethylolpropane tetraacrylate, glycerol diacrylate, methoxide Shi of cyclohexyl diacrylate, neopentyl glycol diacrylate, propylene glycol diacrylate, polypropylene glycol diacrylate, triglycerol diacrylate,
Trimethylolpropane triacrylate, acrylamide, aminoethyl acrylate and those obtained by changing some or all of the acrylate in the molecule of the above compound to methacrylate, γ-methacryloxypropyltrimethoxysilane, 1-vinyl-2-pyrrolidone, etc. Can be

In the present invention, one or more of these can be used. In addition to these, the developability after exposure can be improved by adding an unsaturated acid such as an unsaturated carboxylic acid. Specific examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid,
Examples thereof include crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof.

On the other hand, examples of the photosensitive oligomer or photosensitive polymer include methacrylate monmers or acrylate monomers having an aromatic ring such as a benzene ring and a naphthalene ring, specifically, phenyl (meth) acrylate and phenoxyethyl (meth) acrylate. , Benzyl (meth) acrylate, 1-naphthyl (meth) acrylate, 2-naphthyl (meth) acrylate, bisphenol A di (meth) acrylate, di (meth) acrylate of bisphenol A-ethylene oxide adduct, bisphenol A-propylene oxide Di (meth) acrylate, thiophenol (meth) acrylate, benzyl mercaptan (meth) acrylate of the adduct, and 1 to 5 hydrogen atoms of these aromatic rings were substituted with chlorine or bromine atoms Nomar, compounds shown by the general formula, or, styrene, p- methyl styrene,
o-methylstyrene, m-methylstyrene, chlorinated styrene, brominated styrene, α-methylstyrene, chlorinated α
Oligomers or polymers obtained by polymerizing at least one of -methylstyrene, brominated α-methylstyrene, chloromethylstyrene, and hydroxymethylstyrene can be used.

At the time of polymerization, these monomers can be copolymerized with other photosensitive monomers such that the content of these monomers is at least 10% by weight, more preferably at least 35% by weight. As the monomer to be copolymerized, the aforementioned compound containing a carbon-carbon unsaturated bond can be used.

The developability after exposure can be improved by copolymerizing an unsaturated acid such as an unsaturated carboxylic acid. Specific examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, crotonic acid,
Maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof are exemplified.

The polymer or oligomer having an acidic group such as a carboxyl group in the side chain thus obtained has an acid value (AV) of preferably from 50 to 180, more preferably from 70 to 140. When the acid value is less than 50, the allowable development width becomes narrow. On the other hand, if the acid value exceeds 180, the solubility of the unexposed portion in the developing solution decreases, so that if the developing solution concentration is increased, peeling occurs up to the exposed portion, making it difficult to obtain a high-definition pattern.

Photosensitivity can be imparted to the above-mentioned polymer or oligomer by adding a photoreactive group to a side chain or a molecular terminal. Preferred photoreactive groups are those having an ethylenically unsaturated group. Examples of the ethylenically unsaturated group 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 an ethylenically unsaturated compound having a glycidyl group or an isocyanate group or an acrylic acid, with respect 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 crotonate, and glycidyl ether isocrotonic acid. .

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 one molar equivalent.

In the photosensitive paste used in the present invention, a binder, a photopolymerization initiator, an ultraviolet light absorber, a sensitizer, a sensitization aid, a polymerization inhibitor, a plasticizer, a thickener, an organic solvent, an antioxidant Additive components such as agents, dispersants, and organic or inorganic suspending agents may also be added.

As the binder, polyvinyl alcohol, polyvinyl butyral, methacrylate polymer, acrylate polymer, acrylate ester
Examples include methacrylate copolymers, α-methylstyrene polymers, and butyl methacrylate resins. It is also effective to increase the refractive index of the binder component to increase the refractive index of the photosensitive organic component. As a method for increasing the refractive index of the binder component, any of the above-described photosensitive polymers and photosensitive oligomers in which an ethylenically unsaturated group that is a photoreactive group is not added to a side chain or a molecular terminal can be used. In other words, those in which the step of providing the reactive group of the photosensitive polymer or the photosensitive oligomer is omitted can be used as the binder.

As specific examples of the photopolymerization initiator,
Benzophenone, methyl o-benzoylbenzoate, 4,
4-bis (dimethylamine) benzophenone, 4,4-
Bis (diethylamino) benzophenone, 4,4-dichlorobenzophenone, 4-benzoyl-4-methyldiphenylketone, dibenzylketone, fluorenone, 2,
2-diethoxyacetophenone, 2,2-dimethoxy-
2-phenyl-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyldichloroacetophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl, Benzyl dimethyl ketanol, benzyl methoxyethyl acetal, benzoin, benzoin methyl ether, benzoin butyl ether, anthraquinone,
2-t-butylanthraquinone, 2-amylanthraquinone, β-chloroanthraquinone, anthrone, benzanthrone, dibenzosuberone, methyleneanthrone,
4-azidobenzalacetophenone, 2,6-bis (p
-Azidobenzylidene) cyclohexanone, 2,6-bis (p-azidobenzylidene) -4-methylcyclohexanone, 2-phenyl-1,2-butadione-2- (o
-Methoxycarbonyl) oxime, 1-phenyl-propanedione-2- (o-ethoxycarbonyl) oxime, 1,3-diphenyl-propanetrione-2- (o
-Ethoxycarbonyl) oxime, 1-phenyl-3-
Ethoxy-propanetrione-2- (o-benzoyl)
Oxime, Michler's ketone, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, naphthalenesulfonyl chloride, quinoline sulfonyl chloride, N-phenylthioacridone, 4,4
-Azobisisobutyronitrile, diphenyl disulfide, benzothiazole disulfide, triphenylphorphine, camphorquinone, carbon tetrabromide, tribromophenylsulfone, benzoin peroxide and eosin,
Examples include a combination of a photoreducing dye such as methylene blue and a reducing agent such as ascorbic acid and 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 5% 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 too small.

It is also effective to add an ultraviolet absorber. A high aspect ratio, high definition, and high resolution can be obtained by adding a light absorbing agent having a high ultraviolet absorbing effect. UV absorbers composed of organic dyes, especially 35
Organic dyes having a high UV absorption coefficient in the wavelength range of 0 to 450 nm are preferably used. Specifically, azo dyes, aminoketone dyes, xanthene dyes, quinoline dyes, aminoketone dyes, anthraquinones, benzophenones, diphenylcyanoacrylates, triazines, p-aminobenzoic acid dyes and the like can be used. . Even when the organic dye is added as a light absorbing agent, it is preferable because deterioration of the insulating film characteristics due to the light absorbing agent can be reduced without remaining in the insulating film after firing. Among these, azo dyes and benzophenone dyes are preferred. The addition amount of the organic dye is preferably 0.05 to 5 parts by weight. When the content is less than 0.05% by weight, the effect of adding the ultraviolet absorber is reduced, and
Exceeding the range is not preferred because the properties of the insulating film after firing deteriorate. More preferably, it is 0.15 to 1% by weight. To give an example of the method of adding an ultraviolet light absorber composed of an organic pigment, to prepare a solution in which the organic pigment was previously dissolved in an organic solvent,
Next, the glass powder can be mixed with the organic solvent and dried. By this method, a so-called capsule-like powder in which an organic film is coated on the surface of each glass powder can be produced.

In the present invention, P contained in inorganic fine particles
In some cases, metals such as b, Fe, Cd, Mn, Co, and Mg and oxides thereof react with photosensitive components contained in the paste, causing the paste to gel in a short time, making application impossible. In order to prevent such a reaction, it is preferable to add a stabilizer to prevent gelation. As the stabilizer used, a triazole compound is preferably used.
Among the triazole compounds, benzotriazole works particularly effectively. As an example of the surface treatment of glass powder with benzotriazole used in the present invention, a predetermined amount of benzotriazole with respect to inorganic fine particles was dissolved in an organic solvent such as methyl acetate, ethyl acetate, ethyl alcohol, and methyl alcohol. Thereafter, the particles are immersed in the solution for 1 to 24 hours so that the particles can be sufficiently immersed. After immersion, preferably, the powder is naturally dried at 20 to 30 ° C., and the solvent is evaporated to prepare a powder which has been subjected to a triazole treatment. The ratio of the stabilizer used (stabilizer / inorganic fine particles) is preferably 0.05 to 5% by weight.

A sensitizer is added to improve the sensitivity. Specific examples of the sensitizer include 2,4-diethylthioxanthone, isopropylthioxanthone, 2,3-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)- Isonaphthothiazole, 1,3-bis (4-
Dimethylaminobenzal) acetone, 1,3-carbonyl-bis (4-diethylaminobenzal) acetone,
3,3-carbonyl-bis (7-diethylaminocoumarin), N-phenyl-N-ethylethanolamine, N
-Phenylethanolamine, N-tolyldiethanolamine, N-phenylethanolamine, isoamyl dimethylaminobenzoate, isoamyl diethylaminobenzoate, 3-phenyl-5-benzoylthiotetrazole, 1-phenyl-5-ethoxycarbonylthiotetrazole and the like. Can be 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 addition amount is usually 0.05 to 40% by weight, more preferably 5 to 40% by weight, based on the amount of organic substances. If the amount of the sensitizer is too small, the effect of improving the light sensitivity is not exhibited. Further, the sensitizer has absorption near the exposure wavelength, and generally has a remarkable effect of improving the refractive index at the exposure wavelength.

The polymerization inhibitor is added to improve the thermal stability during storage. Specific examples of the polymerization inhibitor include hydroquinone, monoesterified hydroquinone,
N-nitrosodiphenylamine, phenothiazine, p-
t-butylcatechol, N-phenylnaphthylamine,
2,6-di-t-butyl-p-methylphenol, chloranil, pyrogallol and the like. When adding a polymerization inhibitor, the amount added, in the photosensitive paste,
Usually, it is 0.001 to 1% by weight.

Specific examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, polyethylene glycol, glycerin and the like.

The antioxidant is added to prevent oxidation of the acrylic copolymer during storage. Specific examples of antioxidants include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, and 2,6-di-t.
-4-ethylphenol, 2,2-methylene-bis-
(4-methyl-6-t-butylphenol), 2,2-
Methylene-bis- (4-ethyl-6-t-butylphenol), 4,4-bis- (3-methyl-6-t-butylphenol), 1,1,3-tris- (2-methyl-6
-T-butylphenol), 1,1,3-tris- (2
-Methyl-4-hydroxy-t-butylphenyl) butane, bis [3,3-bis- (4-hydroxy-3-t-
[Butylphenyl) butyric acid] glycol ester, dilaurylthiodipropionate, triphenylphosphite and the like. When adding an antioxidant, the amount added is usually 0.001 to 1% by weight in the paste.

When it is desired to adjust the viscosity of the solution, an organic solvent may be added to the photosensitive paste of the present invention. The organic solvent used at this time includes methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyrolactone, bromobenzene, Chlorobenzene, dibromobenzene, dichlorobenzene, bromobenzoic acid, chlorobenzoic acid, and the like, and an organic solvent mixture containing at least one of these are used.

The photosensitive paste is usually prepared by mixing various components such as inorganic fine particles, an ultraviolet absorber, a photosensitive polymer, a photosensitive monomer, a photopolymerization initiator, a glass frit and a solvent so as to have a predetermined composition. The mixture is uniformly mixed and dispersed with three rollers or a kneading machine.

The viscosity of the paste is appropriately adjusted depending on the addition ratio of inorganic fine particles, a thickener, an organic solvent, a plasticizer, a suspending agent, etc., but the range is from 2000 to 200,000 cp.
s (centipoise). For example, when applying to a glass substrate by a spin coating method other than the screen printing method, 2000 to 5000 cps is preferable. In order to obtain a film thickness of 10 to 20 μm by applying once by the screen printing method,
50,000 to 200,000 cps is preferable.

Next, an example of performing pattern processing using a photosensitive paste will be described, but the present invention is not limited to this. A photosensitive paste is applied entirely or partially on a glass substrate or a ceramic substrate. As a coating method, a known method such as screen printing, a bar coater, and a roll 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 the paste is applied on a glass substrate, a surface treatment of the substrate can be performed in order 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, and γ- (methacryloxy). Propyl) 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. Next, the surface treatment liquid is uniformly applied on a substrate by a spinner or the like, and then applied at a temperature of 80 to 140 ° C. for 10 to 60 minutes so that surface treatment can be performed. Then, mask exposure is performed using a photomask. As the mask to be used, either a negative type or a positive type is selected depending on the type of the photosensitive organic component. The active light source used at this time includes, for example, near-ultraviolet light, ultraviolet light, an electron beam, and X-ray. Among them, ultraviolet light is preferable, and examples of the light source include a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, Halogen lamps, germicidal lamps and the like can be used. Among these, an ultra-high pressure mercury lamp is preferred. Exposure conditions vary depending on the coating thickness, but exposure is performed for 0.1 to 30 minutes using an ultra-high pressure mercury lamp having an output of 5 to 100 mW / cm ² .

After applying the photosensitive paste, the pattern shape can be improved by providing an oxygen shielding film on the surface of the photosensitive paste. As an example of the oxygen shielding film, PV
A film. The method for forming the PVA film has a concentration of 0.
After uniformly applying an aqueous solution of 5 to 5% by weight on a substrate by a method such as a spinner, the preferred PVA solution concentration is 1 to 3% by weight at 70 to 90 ° C for 10 to 60 minutes. Within this range, the sensitivity is further improved. The reason why the sensitivity is improved by the PVA application is presumed as follows. That is, when the photosensitive component undergoes a photoreaction, it is considered that the presence of oxygen in the air interferes with the photocuring sensitivity. However, the presence of a PVA film improves the sensitivity during exposure because excess oxygen can be blocked, which is preferable. . In addition to PVA, a water-soluble and transparent polymer such as cellulosic methylcellulose can also be used.

After the exposure, development is performed using a developing solution. In this case, the development is performed by an immersion method or a spray method. As the developing solution, an organic solvent in which an organic component in the photosensitive paste can be dissolved can be used. Water may be added to the organic solvent as long as the solvent does not lose its solubility. 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 alkali aqueous solution, a metal alkali aqueous solution such as a sodium hydroxide or calcium hydroxide aqueous solution can be used, but it is preferable to use an organic alkali aqueous solution since the alkali component can be easily removed at the time of firing. As the organic alkali, a known 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 0.01 to 10% by weight, more preferably 0.1 to 10% by weight.
1 to 5% by weight. If the alkali concentration is too low, the unexposed portions are not removed, and if the alkali concentration is too high, the pattern portions may be peeled off and the exposed portions may be corroded, which is not good.

Next, firing is performed in a firing furnace. The firing atmosphere and temperature vary depending on the type of paste or substrate, but usually firing is performed in air or a nitrogen atmosphere. Firing temperature is 4
Perform at 00-1000 ° C. 520 when pattern processing is performed on a glass substrate or when silver is used as inorganic fine particles.
The sintering is performed at a temperature of 温度 610 ° C. for 10 to 60 minutes.

In the above steps, a heating step at 50 to 300 ° C. may be introduced for the purpose of drying and preliminary reaction.

By coating the photosensitive paste of the present invention on a polyester film or the like, a photosensitive green sheet used for a circuit material or a display can be obtained.

[0068]

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

In the example, a photosensitive paste comprising glass fine particles and an organic component was prepared.

The preparation procedure was as follows. First, 25 g of an organic component was dissolved in 15 g of a solvent while heating at 80 ° C., and then 60 g of glass particles were added and kneaded with a three-roller kneader to prepare a paste.

Next, on a 30 cm square soda glass substrate, 100 μm was applied by a screen printing method a plurality of times.
The coating was performed so as to have a coating thickness of m and 150 μm, and then dried at 80 ° C. for 30 minutes. Next, exposure was performed using a photomask.

The photomask is a chrome mask designed to have a pitch of 220 μm, a line width of 60 μm, and to be able to form a striped partition pattern in a plasma display.

Exposure was performed with an ultra-high pressure mercury lamp having an output of 50 mW / cm ² for ultraviolet exposure. Then, it was immersed in a 1% aqueous solution of monoethanolamine to perform development. Further, after the obtained glass substrate was dried at 120 ° C. for 1 hour, it was baked at 580 ° C. for 1 hour. About 20
% Shrinkage occurs.

In the evaluation, the pattern shape (target having a line width of 50 μm, a height of 80 μm or 120 μm, and a pitch of 220 μm) was observed with an electron microscope. Height 8
When both 0 μm and 120 μm have good shapes, ○: when only 80 μm has a good shape, Δ: when both 80 μm, 120 μm do not have good shape due to lack, etc. The evaluation was made as follows.

The refractive index of the organic component was measured by an ellipsometry method with respect to light having a wavelength of 436 nm at 25 ° C.

The glass fine particles have a composition of Si
O ₂ ; 20%, Al ₂ O ₂ ; 24%, B ₂ O ₃ ; 31%, L
i ₂ O; 9%, MgO; 6%, CaO; 4%, BaO;
4%, ZrO ₂ ; 2% of glass powder A and composition of Si
O ₂ ; 14%, Al ₂ O ₂ ; 4%, B ₂ O ₃ ; 18%, Bi ₂
O ₃ ; 27%, ZnO; 21%, Na ₂ O; 2%, Ba
O: 14% glass powder B was used. Glass powder A has an average particle size of 2.6 μm, a specific surface area of 4.1 m ² / g, a glass transition temperature Tg of 490 ° C., and a thermal softening temperature Ts of 528.
° C, a sphericity of 3%, a refractive index of 1.5 at a wavelength of 436 nm.
9 is a glass powder. Glass powder B has an average particle size of 3.
5 μm, specific surface area; 3.1 m ² / g, glass transition temperature T
g is 485 ° C., the thermal softening temperature Ts is 527 ° C., and the sphericity is 95.
% Is a glass powder having a refractive index of 1.73 at a wavelength of 436 nm.

Example 1 A photosensitive paste was prepared using glass powder A and an organic substance having a composition 1 shown in Table 1, and a pattern was formed. As a result, good shapes were obtained for both the heights of 80 μm and 120 μm.

Example 2 A photosensitive paste was prepared using glass powder A and an organic substance having a composition 2 shown in Table 1, and a pattern was formed. As a result, favorable shapes were obtained for both 80 μm and 120 μm.

Example 3 A photosensitive paste was prepared using glass powder B and an organic substance having the composition 3 shown in Table 1, and a pattern was formed. As a result, favorable shapes were obtained for both 80 μm and 120 μm.

Comparative Example 1 A photosensitive paste was prepared using glass powder B and an organic substance having composition 4 shown in Table 1, and a pattern was formed. As a result, a pattern could not be formed at both 80 μm and 120 μm in height (development). Peeling occurred, and defective development occurred between the patterns.)

[0081]

[Table 1] Abbreviations in the table are shown below.

(The numbers in the structure of Polymer 1 indicate the constituent molar ratios of the respective monomers. The refractive index is 436 nm.
BMEXS-MA:

Embedded image (Refractive index: 1.63) MPS-MA:

Embedded image (Refractive index: 1.70) MPS-V:

Embedded image (Refractive index: 1.74) Polymer 1:

Embedded image (Weight average molecular weight 23000) TMPTA: trimethylol propane triacrylate Sudan: azo _{dyes, C 24 H 20 N 4 O} MTPMP: 2- methyl-1- [4- (methylthio) phenyl] -2-morpholino propan -1 EPA : P-dimethylaminobenzoic acid ethyl ester DET: 2,4-diethylthioxanthone

[0083]

According to the photosensitive paste of the present invention, pattern processing with a high aspect ratio and high precision can be performed. As a result, a thick film such as a display or a circuit material, and a high-precision pattern processing can be performed, and the definition can be improved and the process can be simplified. In particular, a highly accurate partition wall of a plasma display panel can be formed easily.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G03F 7/004 501 G03F 7/004 501 H01J 9/227 H01J 9/227 E

Claims (11)

[Claims] 1. A photosensitive paste comprising an organic component containing inorganic fine particles and a photoreactive compound as an essential component, wherein the photoreactive compound contains a photoreactive monomer having a refractive index of 1.55 to 1.8. A photosensitive paste, characterized in that: 2. The photosensitive paste according to claim 1, wherein 60% by weight or more of the inorganic fine particles are glass fine particles. 3. A glass transition temperature of 35 as glass fine particles.
The photosensitive paste according to claim 2, wherein glass fine particles having a temperature of 0 to 500 ° C., a thermal softening temperature of 400 to 600 ° C., and an average particle size of 1 to 8 μm are used. 4. The photosensitive paste according to claim 2, wherein glass fine particles containing at least one of bismuth oxide and lead oxide in an amount of 10 to 80% by weight are used as the glass fine particles. 5. The method according to claim 1, wherein at least one of sodium oxide, potassium oxide and lithium oxide is used as glass fine particles.
3. The photosensitive paste according to claim 2, wherein glass fine particles containing up to 20% by weight are used. 6. The photosensitive paste according to claim 2, wherein glass fine particles having a sphericity of 80% by number or more are used in an amount of 50% by weight or more. 7. A glass fine particle having a refractive index of 1.55 to 1.55.
3. The photosensitive paste according to claim 2, wherein 1.8 glass fine particles are used. 8. The photosensitive paste according to claim 1, wherein a polyfunctional (meth) acrylate compound is used as the photoreactive monomer. 9. The photosensitive paste according to claim 1, wherein a polyfunctional compound having a structure represented by the following general formula is used as the photoreactive monomer. Embedded image (X and Y each represent a substituent containing a radical polymerizable functional group.) 10. The photosensitive paste according to claim 1, wherein the organic component contains 0.05 to 5% by weight of a compound having an ultraviolet absorbing property. 11. A method for manufacturing a plasma display, comprising forming the partition of the plasma display through the steps of applying the photosensitive paste, exposing, developing, and baking according to claim 1.