JP5843604B2 - Photosensitive resin composition for black column spacer, black column spacer, display device, and method for forming black column spacer - Google Patents

Description

  The present invention relates to a photosensitive resin composition for black column spacers, a black column spacer formed using the composition, a display device including the black column spacer, and a method for forming a black column spacer using the composition. .

  In a display device such as a liquid crystal display device or an organic EL display device, a spacer is used in order to keep a distance (cell gap) between two substrates constant.

  Conventionally, in order to form a spacer, a method of dispersing bead particles serving as a spacer over the entire surface of a substrate has been adopted. However, this method has a problem in that it is difficult to form a spacer with high positional accuracy, and beads adhere to the pixel display portion, resulting in a decrease in image contrast and display image quality.

  In order to solve these problems, various methods for forming the spacer with the photosensitive resin composition have been proposed. In this method, a photosensitive resin composition is applied onto a substrate, exposed through a predetermined mask, and then developed to form a column-like spacer. A predetermined portion other than a pixel display portion Only the spacer can be formed. In recent years, a so-called black column spacer in which the spacer is provided with a light shielding property by a light shielding agent such as carbon black has also been proposed (Patent Document 1, etc.).

JP 2011-170075 A JP 2006-225503 A

  By the way, it is desired for the black column spacer to have a lower relative dielectric constant. Moreover, in order to prevent light leakage, it is requested | required that light-shielding property is high.

Conventionally, as a light-shielding agent capable of realizing a black matrix having a high light-shielding property and a low relative dielectric constant, fine particles mainly composed of a silver-tin alloy have been proposed (Patent Document 2, etc.). It is conceivable to use fine particles as a component as a light-shielding agent.
However, as a result of studies by the present inventors, when this light-shielding agent is contained, a black column spacer formed on the substrate can be obtained by using a resin having a cardo structure as used in Patent Document 1 as an alkali-soluble resin. It has been found that the diameter of the uppermost part of the black column is significantly smaller than the diameter of the lowermost part, and the shape of the black column spacer is deteriorated.

  Therefore, the present invention uses a photosensitive resin composition for a black column spacer capable of forming a black column spacer having a good shape while using fine particles mainly composed of a silver-tin alloy as a light shielding agent, and the composition. It is an object of the present invention to provide a black column spacer formed in this manner, a display device including the black column spacer, and a method for forming the black column spacer using the composition.

  The inventors of the present invention have made extensive studies to achieve the above object. As a result, it has been found that the above problem can be solved by using a specific alkali-soluble resin together with fine particles mainly composed of a silver-tin alloy, and the present invention has been completed. Specifically, the present invention provides the following.

  A first aspect of the present invention includes an alkali-soluble resin, a photopolymerizable monomer, a photopolymerization initiator, and fine particles mainly composed of a silver-tin alloy, and the alkali-soluble resin includes a resin having a cardo structure and an epoxy. The photosensitive resin composition for black column spacers containing resin.

  The second aspect of the present invention is a black column spacer formed from the photosensitive resin composition for a black column spacer according to the first aspect, and the third aspect of the present invention is a black column according to the second aspect. A display device including a column spacer.

  According to a fourth aspect of the present invention, there is provided a coating step in which the photosensitive resin composition for black column spacer according to the first aspect is applied on a substrate to form a photosensitive resin layer; A black column spacer forming method includes an exposure step of exposing in accordance with a spacer pattern, and a developing step of developing the exposed photosensitive resin layer to form a spacer pattern.

  According to the present invention, a photosensitive resin composition for a black column spacer capable of forming a black column spacer having a good shape while using fine particles mainly composed of a silver-tin alloy as a light-shielding agent, and using the composition The black column spacer formed in this way, a display device including the black column spacer, and a method for forming the black column spacer using the composition can be provided.

≪Photosensitive resin composition for black column spacer≫
The photosensitive resin composition for black column spacers according to the present invention (hereinafter simply referred to as “photosensitive resin composition”) is mainly composed of an alkali-soluble resin, a photopolymerizable monomer, a photopolymerization initiator, and a silver-tin alloy. Containing fine particles. Hereinafter, each component contained in the photosensitive resin composition according to the present invention will be described.

<(A) Alkali-soluble resin>
The alkali-soluble resin is a resin film having a resin concentration of 20% by mass (solvent: propylene glycol monomethyl ether acetate), and a 1 μm-thick resin film is formed on the substrate and placed in a 0.05% by mass KOH aqueous solution for 1 minute. When immersed, it means a film that dissolves 0.01 μm or more in thickness.

  The photosensitive resin composition according to the present invention contains (A) an alkali-soluble resin and (A1) a resin having a cardo structure and (A2) an epoxy resin. By including both (A1) a resin having a cardo structure and (A2) an epoxy resin, a black column spacer having a good shape can be formed. More specifically, when the photosensitive resin composition according to the present invention is exposed and developed, and further post-baked at 230 ° C. for 20 minutes to obtain a black column spacer having a diameter of 25 to 35 μm, the black column The diameter B at the lowermost part of the spacer and the diameter T in the vicinity of the uppermost part (thickness part of 95% from the lowermost part) satisfy the relational expression of (T / B) × 100> 50.

  (A1) The resin having a cardo structure is not particularly limited, and conventionally known resins can be used. Among these, the resin represented by the following formula (a-1) is preferable.

In the formula ^{(a-1), X} a represents a group represented by the following formula (a-2).

In the above formula (a-2), each R ^a1 independently represents a hydrogen atom, a hydrocarbon group having 1 to 6 carbon atoms, or a halogen atom, each R ^a2 independently represents a hydrogen atom or a methyl group, W ^a represents a single bond or a group represented by the following formula (a-3).

In the formula (a-1), Y ^a represents a residue obtained by removing an acid anhydride group (—CO—O—CO—) from a dicarboxylic acid anhydride. Examples of dicarboxylic acid anhydrides include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, chlorendic anhydride, methyltetrahydro Examples thereof include phthalic anhydride and glutaric anhydride.

Further, in the above formula ^(a-1), Z a represents a residue obtained by removing two acid anhydride groups from a tetracarboxylic acid dianhydride. Examples of tetracarboxylic dianhydrides include pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, biphenyl tetracarboxylic dianhydride, biphenyl ether tetracarboxylic dianhydride, and the like.
Moreover, in said formula (a-1), m shows the integer of 0-20.

  (A1) The mass average molecular weight of the resin having a cardo structure is preferably 1000 to 40000, and more preferably 2000 to 30000. By setting it as the above range, sufficient heat resistance and film strength can be obtained while obtaining good developability.

  In addition, the (A2) epoxy resin is not particularly limited, and a conventionally known epoxy resin can be used, and an ethylenically unsaturated group can be used even if it does not have an ethylenically unsaturated group. You may have.

  As an epoxy resin not having an ethylenically unsaturated group, for example, a resin (A2-1) obtained by at least copolymerizing an unsaturated carboxylic acid and an epoxy group-containing unsaturated compound can be used.

Examples of unsaturated carboxylic acids include monocarboxylic acids such as (meth) acrylic acid and crotonic acid; dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, mesaconic acid, and itaconic acid; and anhydrides of these dicarboxylic acids; It is done. Among these, (meth) acrylic acid and maleic anhydride are preferable in terms of copolymerization reactivity, alkali solubility of the resulting resin, availability, and the like. These unsaturated carboxylic acids can be used alone or in combination of two or more.
In the present specification, “(meth) acrylic acid” means both acrylic acid and methacrylic acid.

  The proportion of the structural unit derived from the unsaturated carboxylic acid (the structural unit having a carboxyl group) in the resin (A2-1) is preferably 5 to 29% by mass, more preferably 10 to 25% by mass. preferable. By setting it as the said range, the developability of the photosensitive resin composition can be made moderate.

  The epoxy group-containing unsaturated compound may have no alicyclic epoxy group or may have an alicyclic epoxy group, but more preferably has an alicyclic epoxy group.

  Examples of the epoxy group-containing unsaturated compound having no alicyclic epoxy group include glycidyl (meth) acrylate, 2-methylglycidyl (meth) acrylate, 3,4-epoxybutyl (meth) acrylate, and 6,7-epoxyheptyl. (Meth) acrylate, 3,4-epoxycyclohexyl (meth) acrylate and other (meth) acrylic acid epoxy alkyl esters; α-ethyl acrylate glycidyl, α-n-propyl acrylate glycidyl, α-n-butyl acrylic acid Α-alkylacrylic acid epoxy alkyl esters such as glycidyl and α-ethylacrylic acid 6,7-epoxyheptyl; glycidyl ethers such as o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether and p-vinylbenzyl glycidyl ether ;etc Is mentioned. Among these, glycidyl (meth) acrylate, 2-methylglycidyl (meth) acrylate, 6,7-epoxyheptyl (meth) acrylate, o-vinylbenzyl from the viewpoints of copolymerization reactivity, strength of cured resin, and the like. Glycidyl ether, m-vinylbenzyl glycidyl ether, and p-vinylbenzyl glycidyl ether are preferred.

  The alicyclic group of the epoxy group-containing unsaturated compound having an alicyclic epoxy group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic group include a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic alicyclic group include a norbornyl group, an isobornyl group, a tricyclononyl group, a tricyclodecyl group, and a tetracyclododecyl group.

  Specifically, examples of the epoxy group-containing unsaturated compound having an alicyclic epoxy group include compounds represented by the following formulas (a4-1) to (a4-16). Among these, in order to make the developability of the photosensitive resin composition appropriate, compounds represented by the following formulas (a4-1) to (a4-6) are preferable, and the following formula (a4-1) The compound represented by (a4-4) is more preferable.

In the above formula, R ^a3 represents a hydrogen atom or a methyl group, R ^a4 represents a divalent aliphatic saturated hydrocarbon group having 1 to 6 carbon atoms, and R ^a5 represents a divalent hydrocarbon having 1 to 10 carbon atoms. Represents a group, and n represents an integer of 0 to 10. R ^a4 is preferably a linear or branched alkylene group such as a methylene group, an ethylene group, a propylene group, a tetramethylene group, an ethylethylene group, a pentamethylene group, or a hexamethylene group. As R ^a4 , for example, methylene group, ethylene group, propylene group, tetramethylene group, ethylethylene group, pentamethylene group, hexamethylene group, phenylene group, cyclohexylene group, —CH ₂ —Ph—CH ₂ — (Ph is A phenylene group) is preferred.

  These epoxy group-containing unsaturated compounds can be used alone or in combination of two or more.

  The proportion of the structural unit derived from the epoxy group-containing unsaturated compound (structural unit having an epoxy group) in the resin (A2-1) is preferably 5 to 90% by mass, and 15 to 75% by mass. Is more preferable. By setting it as the above range, it becomes easy to form a black column spacer having a good shape.

  The resin (A2-1) is preferably one obtained by further copolymerizing an alicyclic group-containing unsaturated compound.

  The alicyclic group of the alicyclic group-containing unsaturated compound may be monocyclic or polycyclic. Examples of the monocyclic alicyclic group include a cyclopentyl group and a cyclohexyl group. Examples of the polycyclic alicyclic group include an adamantyl group, a norbornyl group, an isobornyl group, a tricyclononyl group, a tricyclodecyl group, and a tetracyclododecyl group.

  Specifically, examples of the alicyclic group-containing unsaturated compound include compounds represented by the following formulas (a5-1) to (a5-8). Among these, in order to make the developability of the photosensitive resin composition appropriate, compounds represented by the following formulas (a5-3) to (a5-8) are preferable, and the following formula (a5-3) , (A5-4) is more preferred.

In the above formula, R ^a6 represents a hydrogen atom or a methyl group, R ^a7 represents a single bond or a divalent aliphatic saturated hydrocarbon group having 1 to 6 carbon atoms, and R ^a8 represents a hydrogen atom or 1 to 5 carbon atoms. Represents an alkyl group. R ^a7 is preferably a single bond or a linear or branched alkylene group such as a methylene group, an ethylene group, a propylene group, a tetramethylene group, an ethylethylene group, a pentamethylene group, or a hexamethylene group. As R ^a8 , for example, a methyl group and an ethyl group are preferable.

  The proportion of the structural unit derived from the alicyclic group-containing unsaturated compound in the resin (A2-1) is preferably 1 to 40% by mass, and more preferably 5 to 30% by mass.

  Further, the resin (A2-1) may be obtained by further copolymerizing other compounds than the above. Examples of such other compounds include (meth) acrylic acid esters, (meth) acrylamides, allyl compounds, vinyl ethers, vinyl esters, styrenes, and the like. These compounds can be used alone or in combination of two or more.

  As (meth) acrylic acid esters, linear or branched chain such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, amyl (meth) acrylate, t-octyl (meth) acrylate, etc. Alkyl (meth) acrylates; chloroethyl (meth) acrylate, 2,2-dimethylhydroxypropyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, trimethylolpropane mono (meth) acrylate, benzyl (meth) acrylate, furfuryl (Meth) acrylate; etc. are mentioned.

  (Meth) acrylamides include (meth) acrylamide, N-alkyl (meth) acrylamide, N-aryl (meth) acrylamide, N, N-dialkyl (meth) acrylamide, N, N-aryl (meth) acrylamide, N -Methyl-N-phenyl (meth) acrylamide, N-hydroxyethyl-N-methyl (meth) acrylamide and the like.

  Examples of the allyl compound include allyl acetate, allyl caproate, allyl caprylate, allyl laurate, allyl palmitate, allyl stearate, allyl benzoate, allyl acetoacetate, allyl lactate, etc .; allyloxyethanol; Can be mentioned.

  As vinyl ethers, hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethyl hexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, chloroethyl vinyl ether, 1-methyl-2,2-dimethylpropyl vinyl ether, 2-ethylbutyl vinyl ether, hydroxyethyl vinyl ether , Alkyl vinyl ethers such as diethylene glycol vinyl ether, dimethylaminoethyl vinyl ether, diethylaminoethyl vinyl ether, butylaminoethyl vinyl ether, benzyl vinyl ether, tetrahydrofurfuryl vinyl ether; vinyl phenyl ether, vinyl tolyl ether, vinyl chlorophenyl ether, vinyl-2,4-dichloropheny And the like; ethers, vinyl naphthyl ether, vinyl aryl ethers such as vinyl anthranyl ether.

  Vinyl esters include vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl valate, vinyl caproate, vinyl chloroacetate, vinyl dichloroacetate, vinyl methoxyacetate, vinyl butoxyacetate, vinyl vinyl. Examples include enyl acetate, vinyl acetoacetate, vinyl lactate, vinyl-β-phenylbutyrate, vinyl benzoate, vinyl salicylate, vinyl chlorobenzoate, vinyl tetrachlorobenzoate, vinyl naphthoate and the like.

  Styrenes include: styrene; methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, isopropyl styrene, butyl styrene, hexyl styrene, cyclohexyl styrene, decyl styrene, benzyl styrene, chloromethyl styrene, trifluoromethyl styrene, ethoxy Alkyl styrene such as methyl styrene and acetoxymethyl styrene; alkoxy styrene such as methoxy styrene, 4-methoxy-3-methyl styrene and dimethoxy styrene; chlorostyrene, dichlorostyrene, trichlorostyrene, tetrachlorostyrene, pentachlorostyrene, bromostyrene, Dibromostyrene, iodostyrene, fluorostyrene, trifluorostyrene, 2-bromo-4-trifluoromethyl Styrene, halostyrenes such as 4-fluoro-3-trifluoromethyl styrene; and the like.

  The mass average molecular weight of the resin (A2-1) is preferably 2000 to 50000, and more preferably 5000 to 30000. By setting it as the above range, there is a tendency that the film forming ability and developability of the photosensitive resin composition are easily balanced.

  On the other hand, as an epoxy resin having an ethylenically unsaturated group, for example, a carboxyl group of a resin obtained by polymerizing at least an unsaturated carboxylic acid and an epoxy group-containing unsaturated compound, and an epoxy group of an epoxy group-containing unsaturated compound A resin (A2-2) obtained by reacting an unsaturated carboxylic acid and an epoxy group of a resin obtained by polymerizing at least an unsaturated carboxylic acid and an epoxy group-containing unsaturated compound, and a carboxyl group of an unsaturated carboxylic acid. Resin (A2-3) obtained by reacting can be used.

  As unsaturated carboxylic acid and an epoxy group containing unsaturated compound, the compound illustrated by the said resin (A2-1) is mentioned. Therefore, the resin (A2-1) is exemplified as a resin obtained by polymerizing at least an unsaturated carboxylic acid and an epoxy group-containing unsaturated compound.

  The proportion of the structural unit derived from the unsaturated carboxylic acid (the structural unit having a carboxyl group) in the resins (A2-2) and (A2-3) is preferably 5 to 60% by mass, and 10 to 40% by mass. % Is more preferable. By setting it as the said range, the developability of the photosensitive resin composition can be made moderate.

  Moreover, it is preferable that the ratio of the structural unit (structural unit which has an epoxy group) derived from the epoxy group containing unsaturated compound in the said resin (A2-2) and (A2-3) is 5-90 mass%, More preferably, it is 15-75 mass%. By setting it as the above range, it becomes easy to form a black column spacer having a good shape.

  The mass average molecular weight of the resins (A2-2) and (A2-3) is preferably 2000 to 50000, and more preferably 5000 to 30000. By setting it as the above range, there is a tendency that the film forming ability and developability of the photosensitive resin composition are easily balanced.

  In addition to the above, (A2) epoxy resin includes bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol or cresol novolac type epoxy resin, resol type epoxy resin, triphenolmethane type epoxy resin, An epoxy (meth) acrylate resin obtained by reacting an epoxy group of an epoxy resin such as a polycarboxylic acid polyglycidyl ester, a polyol polyglycidyl ester, an amine epoxy resin, or a dihydroxybenzene type epoxy resin with (meth) acrylic acid, etc. It can also be used.

  The (A) alkali-soluble resin may contain other conventionally known alkali-soluble resins in addition to the (A1) resin having a cardo structure and the (A2) epoxy resin. However, the total ratio of the resin having the (A1) cardo structure and the (A2) epoxy resin in (A) the alkali-soluble resin is preferably 80% by mass or more, and 90% by mass or more. Is more preferable, and it is most preferable that it is 100 mass%.

  The proportion of the resin having the (A1) cardo structure in 100 parts by mass of the (A) alkali-soluble resin is preferably 10 to 90 parts by mass, and more preferably 20 to 70 parts by mass. On the other hand, in 100 parts by mass of the (A) alkali-soluble resin, the proportion of the (A2) epoxy resin is preferably 10 to 90 parts by mass, and more preferably 20 to 70 parts by mass.

The ratio of the resin having the (A1) cardo structure and the (A2) epoxy resin is preferably 99: 1 to 1:99, and 95: 5 to 40:60 on a mass basis. More preferably, it is more preferably 90:10 to 45:55, particularly preferably 85:15 to 50:50, and most preferably 80:20 to 60:40.
By setting it as the above range, it becomes easy to form a black column spacer having a good shape.

  (A) The content of the alkali-soluble resin is preferably 40 to 85% by mass and more preferably 45 to 75% by mass with respect to the solid content of the photosensitive resin composition. By setting it as the above range, there is a tendency that developability is easily balanced.

<(B) Photopolymerizable monomer>
Photopolymerizable monomers include monofunctional monomers and polyfunctional monomers.
Monofunctional monomers include (meth) acrylamide, methylol (meth) acrylamide, methoxymethyl (meth) acrylamide, ethoxymethyl (meth) acrylamide, propoxymethyl (meth) acrylamide, butoxymethoxymethyl (meth) acrylamide, N-methylol ( (Meth) acrylamide, N-hydroxymethyl (meth) acrylamide, (meth) acrylic acid, fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, crotonic acid, 2-acrylamide- 2-methylpropane sulfonic acid, tert-butylacrylamide sulfonic acid, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate Cyclohexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2- (Meth) acryloyloxy-2-hydroxypropyl phthalate, glycerin mono (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dimethylamino (meth) acrylate, glycidyl (meth) acrylate, 2,2,2-trifluoroethyl ( And (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, and half (meth) acrylate of a phthalic acid derivative. These monofunctional monomers can be used alone or in combination of two or more.

  On the other hand, as the polyfunctional monomer, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol Di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexane glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol triacrylate, pentaerythritol Tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, pentaerythritol di (meta Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 2,2-bis (4- (meth) acryloxydi Ethoxyphenyl) propane, 2,2-bis (4- (meth) acryloxypolyethoxyphenyl) propane, 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate, ethylene glycol diglycidyl ether di (meth) Acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, diglycidyl phthalate ester di (meth) acrylate, glycerin triacrylate, glycerin polyglycidyl ether poly (Meth) acrylate, urethane (meth) acrylate (ie, tolylene diisocyanate), reaction product of trimethylhexamethylene diisocyanate, hexamethylene diisocyanate and 2-hydroxyethyl (meth) acrylate, methylenebis (meth) acrylamide, (meth) acrylamide methylene Examples thereof include polyfunctional monomers such as ethers, polyhydric alcohols and N-methylol (meth) acrylamide condensates, and triacryl formal. These polyfunctional monomers can be used alone or in combination of two or more.

  (B) It is preferable that content of a photopolymerizable monomer is 1-30 mass% with respect to solid content of the photosensitive resin composition, and it is more preferable that it is 5-20 mass%. By setting it as the above range, it tends to be easy to balance sensitivity, developability, and resolution.

<(C) Photopolymerization initiator>
It does not specifically limit as a photoinitiator, A conventionally well-known photoinitiator can be used.

  Specific examples of the photopolymerization initiator include 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, and 1- [4- (2-hydroxyethoxy) phenyl] -2- Hydroxy-2-methyl-1-propan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4-dodecylphenyl) -2-hydroxy-2 -Methylpropan-1-one, bis (4-dimethylaminophenyl) ketone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 4-benzoyl-4'-methyldimethylsulfide, 4-dimethylaminobenzoic acid, 4- Methyl dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, 4-dimethylaminobenzoate 4-dimethylamino-2-ethylhexylbenzoic acid, 4-dimethylamino-2-isoamylbenzoic acid, benzyl-β-methoxyethyl acetal, benzyldimethyl ketal, 1-phenyl-1,2-propanedione-2- ( o-ethoxycarbonyl) oxime, methyl o-benzoylbenzoate, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 1-chloro-4-propoxythioxanthone, thioxanthene, 2-chlorothioxanthene 2,4-diethylthioxanthene, 2-methylthioxanthene, 2-isopropylthioxanthene, 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-diphenylanthraquinone, azobisisobu Tyronitrile, benzoyl peroxide, cumene peroxide, 2-mercaptobenzoimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- ( o-chlorophenyl) -4,5-di (methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5 -Diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4,5-triarylimidazole dimer, benzophenone, 2-chlorobenzophenone, 4,4 ' -Bisdimethylaminobenzophenone (ie Michler's ketone), 4 4′-bisdiethylaminobenzophenone (ie, ethyl Michler's ketone), 4,4′-dichlorobenzophenone, 3,3-dimethyl-4-methoxybenzophenone, benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, Benzoin-n-butyl ether, benzoin isobutyl ether, benzoin butyl ether, acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone, p-tert-butylacetophenone, p -Dimethylaminoacetophenone, p-tert-butyltrichloroacetophenone, p-tert-butyldichloroaceto Enone, α, α-dichloro-4-phenoxyacetophenone, thioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, dibenzosuberone, pentyl-4-dimethylaminobenzoate, 9-phenylacridine, 1,7-bis- (9 -Acridinyl) heptane, 1,5-bis- (9-acridinyl) pentane, 1,3-bis- (9-acridinyl) propane, p-methoxytriazine, 2,4,6-tris (trichloromethyl) -s- Triazine, 2-methyl-4,6-bis (trichloromethyl) -s-triazine, 2- [2- (5-methylfuran-2-yl) ethenyl] -4,6-bis (trichloromethyl) -s- Triazine, 2- [2- (furan-2-yl) ethenyl] -4,6-bis (trichloromethyl)- -Triazine, 2- [2- (4-diethylamino-2-methylphenyl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine, 2- [2- (3,4-dimethoxyphenyl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine, 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-ethoxystyryl) -4,6 -Bis (trichloromethyl) -s-triazine, 2- (4-n-butoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2,4-bis-trichloromethyl-6- (3- Bromo-4-methoxy) phenyl-s-triazine, 2,4-bis-trichloromethyl-6- (2-bromo-4-methoxy) phenyl-s-triazine, 2,4-bis -Trichloromethyl-6- (3-bromo-4-methoxy) styrylphenyl-s-triazine, 2,4-bis-trichloromethyl-6- (2-bromo-4-methoxy) styrylphenyl-s-triazine, IRGACURE OXE02 ”,“ IRGACURE OXE01 ”,“ IRGACURE 369 ”,“ IRGACURE 651 ”,“ IRGACURE 907 ”(trade name: manufactured by BASF),“ NCI-831 ”(trade name: manufactured by ADEKA), and the like. These photopolymerization initiators can be used alone or in combination of two or more.

  Among these, use of an oxime photopolymerization initiator is particularly preferable in terms of sensitivity, and an oxime photopolymerization initiator having a carbazole skeleton is particularly preferable.

  Preferable examples of the oxime photopolymerization initiator include a photopolymerization initiator represented by the following formula (c-1).

In the above formula (c-1), R ^c1 represents a heterocyclic group, a condensed cyclic aromatic group, or an aromatic group, which may have a substituent. R ^{c2 to} R ^c4 each independently represent a monovalent organic group.

^Examples of the heterocyclic group for R ^c1 include 5-membered or more, preferably 5- or 6-membered heterocyclic groups containing at least one of a nitrogen atom, a sulfur atom, and an oxygen atom. Examples of heterocyclic groups include nitrogen-containing 5-membered ring groups such as pyrrolyl, imidazolyl and pyrazolyl groups; nitrogen-containing 6-membered ring groups such as pyridyl, pyrazinyl, pyrimidyl and pyridazinyl groups; thiazolyl and isothiazolyl groups Nitrogen-containing sulfur groups such as oxazolyl groups and isoxazolyl groups; sulfur-containing groups such as thienyl groups and thiopyranyl groups; oxygen-containing groups such as furyl groups and pyranyl groups; Among these, those containing one nitrogen atom or one sulfur atom are preferable. This heterocyclic ring may contain a condensed ring. Examples of the heterocyclic group containing a condensed ring include a benzothienyl group.

^Examples of the condensed cyclic aromatic group for R ^c1 include a naphthyl group, an anthryl group, and a phenanthryl group. Moreover, a phenyl group is mentioned as an aromatic group in ^Rc1 .

The heterocyclic group, the condensed cyclic aromatic group, or the aromatic group may have a substituent. In particular, when R ^c1 is an aromatic group, it preferably has a substituent. Examples of such substituent include —NO ₂ , —CN, —SO ₂ R ^c5 , —COR ^c5 , —NR ^c6 R ^c7 , —R ^c8 , —OR ^c8 , —O—R ^c9 —O—R ^{c10, and the} like. Is mentioned.

R ^c5 independently represents an alkyl group, which may be substituted with a halogen atom, and may be interrupted by an ether bond, a thioether bond, or an ester bond. The alkyl group in R ^c5 preferably has 1 to 5 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and an isobutyl group.

R ^c6 and R ^c7 each independently represent a hydrogen atom, an alkyl group, or an alkoxy group, which may be substituted with a halogen atom, and among these, the alkylene group of the alkyl group and the alkoxy group is an ether bond, It may be interrupted by a thioether bond or an ester bond. R ^c6 and R ^c7 may be bonded to form a ring structure. The alkyl group or alkoxy group in R ^c6 and R ^c7 preferably has 1 to 5 carbon atoms. For example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a methoxy group, an ethoxy group, A propoxy group etc. are mentioned.

A ring structure that can be formed by combining R ^c6 and R ^c7 includes a heterocyclic ring. Examples of the heterocyclic ring include 5-membered or more, preferably 5 to 7-membered heterocyclic rings containing at least a nitrogen atom. This heterocyclic ring may contain a condensed ring. Examples of the heterocyclic ring include piperidine ring, morpholine ring, thiomorpholine ring and the like. Among these, a morpholine ring is preferable.

R ^c8 represents an alkyl group in which part or all of the hydrogen atoms may be substituted with a halogen atom. The alkyl group for R ^c8 preferably has 1 to 6 carbon atoms, and examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and an isobutyl group.

R ^c9 and R ^c10 each independently represents an alkyl group, which may be substituted with a halogen atom, and may be interrupted by an ether bond, a thioether bond, or an ester bond. The preferred number of carbon atoms and specific examples thereof are the same as those described above for R ^c1 .

Among these, preferable examples of R ^c1 include a pyrrolyl group, a pyridyl group, a thienyl group, a thiopyralyl group, a benzothienyl group, a naphthyl group, and a phenyl group having a substituent.

In the above formula (c-1), R ^c2 represents a monovalent organic group. The organic group is preferably a group represented by -R ^c11 , -OR ^c11 , -COR ^c11 , -SR ^c11 , -NR ^c11 R ^c12 . R ^c11 and R ^c12 each independently represent an alkyl group, an alkenyl group, an aryl group, an aralkyl group, or a heterocyclic group, which may be substituted with a halogen atom, an alkyl group, or a heterocyclic group, Among them, the alkylene part of the alkyl group and the aralkyl group may be interrupted by an unsaturated bond, an ether bond, a thioether bond, or an ester bond. R ^c11 and R ^c12 may be bonded to form a ring structure with the nitrogen atom.

As an alkyl group in R ^c11 and R ^c12 , one having 1 to 20 carbon atoms is preferable, and one having 1 to 5 carbon atoms is more preferable. Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl. Group, tert-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, isooctyl group, sec-octyl group, tert-octyl group, n-nonyl group, isononyl group, n-decyl group, isodecyl group And a straight chain or branched chain group such as Moreover, this alkyl group may have a substituent. Examples of those having a substituent include a methoxyethoxyethyl group, an ethoxyethoxyethyl group, a propyloxyethoxyethyl group, and a methoxypropyl group.

As an alkenyl group in ^Rc11 and ^Rc12 , a C1-C20 thing is preferable and a C1-C5 thing is more preferable. Examples of alkenyl groups include linear or branched groups such as vinyl, allyl, butenyl, ethenyl, and propynyl groups. Moreover, this alkenyl group may have a substituent. Examples of those having a substituent include 2- (benzoxazol-2-yl) ethenyl group and the like.

As an aryl group in ^Rc11 and ^Rc12 , a C6-C20 thing is preferable and a C6-C10 thing is more preferable. Examples of the aryl group include phenyl group, tolyl group, xylyl group, ethylphenyl group, naphthyl group, anthryl group, phenanthryl group and the like.

As an aralkyl group in R ^c11 and R ^c12 , those having 7 to 20 carbon atoms are preferable, and those having 7 to 12 carbon atoms are more preferable. Examples of the aralkyl group include benzyl group, α-methylbenzyl group, α, α-dimethylbenzyl group, phenylethyl group, phenylethenyl group and the like.

^Examples of the heterocyclic group for R ^c11 and R ^c12 include 5-membered or more, preferably 5- to 7-membered heterocyclic groups containing at least one of a nitrogen atom, a sulfur atom, and an oxygen atom. This heterocyclic group may contain a condensed ring. Examples of the heterocyclic group include pyrrolyl, pyridyl, pyrimidyl, furyl, and thienyl groups.

Among these R ^c11 and R ^c12 , the alkylene part of the alkyl group and the aralkyl group may be interrupted by an unsaturated bond, an ether bond, a thioether bond, or an ester bond.

A ring structure that can be formed by combining R ^c11 and R ^c12 includes a heterocyclic ring. Examples of the heterocyclic ring include 5-membered or more, preferably 5 to 7-membered heterocyclic rings containing at least a nitrogen atom. This heterocyclic ring may contain a condensed ring. Examples of the heterocyclic ring include piperidine ring, morpholine ring, thiomorpholine ring and the like.

Among these, R ^c2 is most preferably a methyl group, an ethyl group, a propyl group, or a phenyl group.

In the above formula (c-1), R ^c3 represents a monovalent organic group. Examples of the organic group include an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms which may have a substituent, a group represented by the following formula (c-2), or a substituent. The heterocyclic group which may have is preferable. Examples of the substituent include the same groups as in R ^c1 above. Examples of the aryl group having 6 to 12 carbon atoms include a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl group.

In the above formula (c-2), R ^c13 represents an alkylene group having 1 to 5 carbon atoms which may be interrupted by an oxygen atom. Examples of such an alkylene group include methylene group, ethylene group, n-propylene group, isopropylene group, n-butylene group, isobutylene group, sec-butylene group, n-pentylene group, isopentylene group, sec-pentylene group and the like. A linear or branched group is mentioned. Among these, R ^c13 is most preferably an ^isopropylene group.

In the formula (c-2), R ^c14 represents a monovalent organic group represented by —NR ^c15 R ^c16 (R ^c15 and R ^c16 each independently represents a monovalent organic group). Among such organic groups, if the structure of R ^c14 is represented by the following formula (c-3), it is preferable in that the solubility of the photopolymerization initiator can be improved.

In the above formula (c-3), R ^c17 and R ^c18 each independently represent an alkyl group having 1 to 5 carbon atoms. Examples of such an alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, sec- Examples thereof include a pentyl group and a tert-pentyl group. Among these, R ^c17 and R ^c18 are most preferably a methyl group.

^Examples of the heterocyclic group for R ^c3 include 5-membered or more, preferably 5-membered or 6-membered heterocyclic groups containing at least one of a nitrogen atom, a sulfur atom, and an oxygen atom. Examples of heterocyclic groups include nitrogen-containing 5-membered ring groups such as pyrrolyl, imidazolyl and pyrazolyl groups; nitrogen-containing 6-membered ring groups such as pyridyl, pyrazinyl, pyrimidyl and pyridazinyl groups; thiazolyl and isothiazolyl groups Nitrogen-containing sulfur groups such as oxazolyl groups and isoxazolyl groups; sulfur-containing groups such as thienyl groups and thiopyranyl groups; oxygen-containing groups such as furyl groups and pyranyl groups; Among these, those containing one nitrogen atom or one sulfur atom are preferable. This heterocyclic ring may contain a condensed ring. Examples of the heterocyclic group containing a condensed ring include a benzothienyl group.

Moreover, the heterocyclic group may have a substituent. Examples of the substituent include the same groups as in R ^c1 above.

In the above formula (c-1), R ^c4 represents a monovalent organic group. Among these, it is preferable that it is a C1-C5 alkyl group. Examples of such an alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, sec- Examples thereof include a pentyl group and a tert-pentyl group. Among these, R ^c4 is most preferably a methyl group.

  Further, another preferred example of the oxime photopolymerization initiator includes a photopolymerization initiator represented by the following formula (c-4) proposed in JP 2010-15025 A.

In the formula (c-4), R ^c21 and R ^c22 each independently represent R ^c31 , OR ^c31 , COR ^c31 , SR ^c31 , CONR ^c32 R ^c33 , or CN.

R ^c31 , R ^c32 , and R ^c33 each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, or 2 to 2 carbon atoms. 20 heterocyclic groups are shown. Alkyl group, aryl group, arylalkyl group, and a hydrogen atom of the heterocyclic group, further ^{OR c41, COR c41, SR c41} , NR c42 R c43, CONR c42 R c43, -NR c42 -OR c43, -NCOR c42 - ^{OCOR c43, -C (= N-} OR c41) -R c42, -C (= N-OCOR c41) -R c42, CN, halogen ^{atom, -CR c41 = CR c42 R c43} , -CO-CR c41 = CR ^It may be substituted with ^c42 R ^c43 , a carboxyl group, or an epoxy group. R ^{c41, R c 42,} and ^{R c43} are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, or 2 carbon atoms 20 heterocyclic groups are shown.

Methylene groups in the alkylene moiety of the substituents on the ^{R c31, R c32, R c33} , R c41, R c42, and ^{R c43} are unsaturated bond, an ether bond, a thioether bond, an ester bond, a thioester bond, an amide bond, or The substituent may be interrupted 1 to 5 times, the alkyl part of the substituent may be branched or cyclic alkyl, and the alkyl terminal of the substituent is an unsaturated bond. At best, ^{also, R c32} and ^{R c33,} and ^{R c 42} and ^{R c43} may form a ring structure, respectively.

In the above formula (c-4), R ^c23 and R ^c24 each independently represent R ^c31 , OR ^c31 , COR ^c31 , SR ^c31 , CONR ^c32 R ^c33 , NR ^c31 COR ^c32 , OCOR ^c31 , COOR ^c31 , SCOR ^c31 , OCSR ^c31 , COSR ^c31 , CSOR ^c31 , CN, a halogen atom, or a hydroxyl group. a and b each independently represent an integer of 0 to 4.
R ^c23 may be bonded to one of the carbon atoms of the adjacent benzene ring via —X ^c2 — to form a ring structure, and R ^c23 and R ^c24 are bonded to form a ring structure. May be.

In the above formula (c-4), X ^c1 represents a single bond or CO.

In the formula (c-4), X ^c2 represents an oxygen atom, a sulfur atom, a selenium atom, CR ^c51 R ^c52 , CO, NR ^c53 , or PR ^c54 . R ^c51 , R ^c52 , R ^c53 , and R ^c54 each independently represent R ^c31 , OR ^c31 , COR ^c31 , SR ^c31 , CONR ^c32 R ^c33 , or CN. R ^c51 , R ^c53 , and R ^c54 may each independently form a ring structure together with any adjacent benzene ring.

In the formula ^(c-4), as the alkyl group in ^{R c31, R c32, R c33} , R c41, R c42, and ^{R c43,} methyl group, ethyl group, n- propyl group, an isopropyl group, n- butyl Group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, sec-pentyl group, tert-pentyl group and the like.

In the formula ^(c-4), the aryl group in ^{R c31, R c32, R c33} , R c41, R c42, and ^{R c43,} a phenyl group, a tolyl group, xylyl group, ethylphenyl group, a chlorophenyl group, a naphthyl Group, anthryl group, phenanthrenyl group and the like.

In the formula ^(c-4), the aryl group in ^{R c31, R c32, R c33} , R c41, R c42, and ^{R c43,} benzyl group, chlorobenzyl group, alpha-methylbenzyl, alpha, alpha -A dimethylbenzyl group, a phenylethyl group, a phenylethenyl group, etc. are mentioned.

In the formula ^(c-4), as the heterocyclic group in ^{R c31, R c32, R c33} , R c41, R c42, and ^{R c43,} pyridyl group, pyrimidyl group, furyl group, a thienyl group, a tetrahydrofuryl group, Dioxolanyl group, benzoxazol-2-yl group, tetrahydropyranyl group, pyrrolidyl group, imidazolidyl group, pyrazolidyl group, thiazolidyl group, isothiazolidyl group, oxazolidyl group, isoxazolidyl group, piperidyl group, piperazyl group, morpholinyl group, etc. A 5- to 7-membered ring is preferable.

In the formula ^(c-4), the ring and ^{R c32} and ^{R c33} may be ^formed by combining the ring and the ^{R c 42} and ^{R c43} may be formed by bonding, and together with the benzene ring ^{to which R c23} is adjacent Examples of the ring that can be formed include 5- to 7-membered rings such as cyclopentane ring, cyclohexane ring, cyclopentene ring, benzene ring, piperidine ring, morpholine ring, lactone ring, and lactam ring.
When X ^c2 is NR ^c53 and R ^c23 is bonded to one of the adjacent carbon atoms of the benzene ring to form a 5-membered ring structure together with X ^c2 , the photopolymerization initiator has a carbazole skeleton. Become.

In the formula ^(c-4), as the halogen atom in ^{R c31, R c32, R c33} , R c41, R c42, and ^{R c43} which may be substituted halogen atoms, and ^{R c24, R c25,} fluorine atom , Chlorine atom, bromine atom and iodine atom.

  The methylene group of the alkylene part of the substituent may be interrupted 1 to 5 times by an unsaturated bond, an ether bond, a thioether bond, an ester bond, a thioester bond, an amide bond, or a urethane bond. In this case, the linking group to be interrupted may be one type or two or more groups, and in the case of a group that can be interrupted continuously, two or more groups may be interrupted continuously. In addition, the alkyl part of the substituent may have a branched chain or may be a cyclic alkyl, and the alkyl terminal of the substituent may be an unsaturated bond.

  (C) It is preferable that content of a photoinitiator is 0.5-20 mass parts with respect to 100 mass parts of solid content of the photosensitive resin composition. By setting it as said range, sufficient heat resistance and chemical-resistance can be acquired, a coating-film formation ability can be improved, and hardening failure can be suppressed.

<(D) Fine particles mainly composed of silver tin alloy>
Fine particles containing silver-tin alloy as a main component (hereinafter referred to as “silver-tin alloy fine particles”) only need to be a silver-tin alloy, and examples of other metal components include Ni, Pd, and Au. It may be.
The average particle diameter of the silver tin alloy fine particles is preferably 1 to 300 nm.

When this silver-tin alloy is represented by the chemical formula Ag _x Sn, the range of x in which a chemically stable silver-tin alloy is obtained is 1 ≦ x ≦ 10, and chemical stability and blackness can be obtained simultaneously. The range of x is 3 ≦ x ≦ 4.
Here, when the mass ratio of silver in the silver-tin alloy is determined in the range of x,
When x = 1, Ag / AgSn = 0.4762
When x = 3, 3 · Ag / Ag ₃ Sn = 0.7317
When x = 4, 4 · Ag / Ag ₄ Sn = 0.7843
When x = 10, 10 · Ag / Ag ₁₀ Sn = 0.008
It becomes. Therefore, this silver tin alloy becomes chemically stable when 47.6 to 90% by mass of silver is contained, and has an effect on the amount of silver when 73.17 to 78.43% by weight of silver is contained. Therefore, chemical stability and blackness can be obtained.

  The silver tin alloy fine particles can be produced using a normal fine particle synthesis method. Examples of the fine particle synthesis method include a gas phase reaction method, a spray pyrolysis method, an atomization method, a liquid phase reaction method, a freeze drying method, and a hydrothermal synthesis method.

The silver-tin alloy fine particles have high insulating properties, but the surface may be covered with an insulating film in order to further improve the insulating properties. As a material for such an insulating film, a metal oxide or an organic polymer compound is suitable.
As the metal oxide, an insulating metal oxide such as silicon oxide (silica), aluminum oxide (alumina), zirconium oxide (zirconia), yttrium oxide (yttria), titanium oxide (titania), etc. is preferably used. It is done.
In addition, as the organic polymer compound, an insulating resin such as polyimide, polyether, polyacrylate, polyamine compound, or the like is preferably used.

The thickness of the insulating film is preferably 1 to 100 nm, and more preferably 5 to 50 nm, in order to sufficiently enhance the surface insulation of the silver-tin alloy fine particles.
This insulating film can be easily formed by a surface modification technique or a surface coating technique. In particular, use of an alkoxide such as tetraethoxysilane or aluminum triethoxide is preferable because an insulating film having a uniform thickness can be formed at a relatively low temperature.

  (C) The content of the silver-tin alloy fine particles is preferably 5 to 50% by mass and more preferably 5 to 30% by mass with respect to the solid content of the photosensitive resin composition. By setting it as said range, a black column spacer with high light-shielding property and a low dielectric constant can be obtained while suppressing photocuring failure.

<(E) Light absorber>
The photosensitive resin composition according to the present invention preferably contains a light absorber.
The light absorber is not particularly limited, and a light absorber that can absorb exposure light can be used. In particular, a light absorber that absorbs light in a wavelength region of 200 to 450 nm is preferable. Examples thereof include naphthalene compounds, dinaphthalene compounds, anthracene compounds, phenanthroline compounds, and dyes.

  Specifically, cinnamic acid derivatives such as 2-ethylhexyl cinnamate, 2-ethylhexyl paramethoxycinnamate, isopropyl methoxycinnamate, isoamyl methoxycinnamate; α-naphthol, β-naphthol, α-naphthol methyl ether, α -Naphthol ethyl ether, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8 -Naphthalene derivatives such as dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene and 2,7-dihydroxynaphthalene; anthracene such as anthracene and 9,10-dihydroxyanthracene and derivatives thereof; azo series Fee, benzophenone dyes, aminoketone dyes, quinoline dyes, anthraquinone dyes, diphenyl cyanoacrylate dyes, triazine dyes, dyes such as p- aminobenzoic acid dyes; and the like. Among these, cinnamic acid derivatives and naphthalene derivatives are preferably used, and cinnamic acid derivatives are particularly preferably used. These light absorbers can be used alone or in combination of two or more.

  (E) It is preferable that content of a light absorber is 0.5-20 mass parts with respect to 100 mass parts of solid content of the photosensitive resin composition. By setting it as said range, the ratio of the film thickness change when changing an exposure amount can be enlarged, keeping the fracture strength after hardening favorable.

<(S) Organic solvent>
The photosensitive resin composition according to the present invention preferably contains an organic solvent for dilution. Examples of the organic solvent include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol-n-propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-propyl ether. , Diethylene glycol mono-n-butyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether, di Propylene glycol monomethyl ether, zip (Poly) alkylene glycol monoalkyl ethers such as pyrene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether; ethylene (Poly) alkylene glycol monoalkyl ether acetates such as glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate; diethylene glycol dimethyl Other ethers such as ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether and tetrahydrofuran; ketones such as methyl ethyl ketone, cyclohexanone, 2-heptanone and 3-heptanone; methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, etc. Lactic acid alkyl esters; ethyl 2-hydroxy-2-methylpropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl ethoxyacetate, hydroxyacetic acid Ethyl, 2-hydroxy-3-methyl methyl carbonate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutylpropionate, ethyl acetate, n-acetate Propyl, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-pentyl formate, isopentyl acetate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, isopropyl butyrate, n-butyl butyrate, methyl pyruvate, ethyl pyruvate , Other esters such as n-propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, ethyl 2-oxobutanoate; aromatic hydrocarbons such as toluene, xylene; N-methylpyrrolidone, N, N-dimethylformamide, Examples thereof include amides such as N, N-dimethylacetamide.

  Among these, alkylene glycol monoalkyl ethers, alkylene glycol monoalkyl ether acetates, other ethers described above, alkyl lactate esters, and other esters described above are preferable, alkylene glycol monoalkyl ether acetates described above. Other ethers and other esters described above are more preferred. These solvents can be used alone or in combination of two or more.

  (S) The content of the organic solvent is preferably such that the solid content concentration of the photosensitive resin composition is 1 to 50% by mass, and more preferably 5 to 30% by mass.

<Other ingredients>
The photosensitive resin composition according to the present invention may contain various additives as necessary. Examples of the additive include a sensitizer, a curing accelerator, a filler, an adhesion promoter, an antioxidant, an aggregation inhibitor, a thermal polymerization inhibitor, an antifoaming agent, and a surfactant.

<Method for preparing photosensitive resin composition>
The photosensitive resin composition according to the present invention is prepared by mixing the above components with a stirrer. In addition, you may filter using a membrane filter etc. so that the prepared photosensitive resin composition may become uniform.

≪Spacer, display device, black column spacer formation method≫
The black column spacer according to the present invention is the same as the conventional black column spacer except that it is formed from the photosensitive resin composition according to the present invention. The display device according to the present invention is the same as the conventional display device except that the display device includes a spacer formed from the photosensitive resin composition according to the present invention. Hereinafter, only the method for forming the black column spacer will be described.

  The method for forming a black column spacer according to the present invention comprises a coating step of coating a photosensitive resin composition according to the present invention on a substrate to form a photosensitive resin layer, and a photosensitive resin layer formed on a predetermined black column spacer. It includes an exposure step of exposing in accordance with the pattern and a development step of developing the exposed photosensitive resin layer to form a black column spacer pattern.

  First, in the coating process, a contact transfer type coating device such as a roll coater, reverse coater or bar coater, a non-contact type such as a spinner (rotary coating device), a curtain flow coater, or the like is formed on a substrate on which a black column spacer is to be formed. The photosensitive resin composition which concerns on this invention is apply | coated using an application | coating apparatus, a solvent is removed by drying as needed, and the photosensitive resin layer is formed.

Next, in the exposure process, the photosensitive resin layer is irradiated with active energy rays such as ultraviolet rays and excimer laser light through a negative mask, and the photosensitive resin layer is partially exposed according to the pattern of the black column spacer. To do. For the exposure, a light source that emits ultraviolet rays such as a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a xenon lamp, or a carbon arc lamp can be used. The amount of exposure varies depending on the composition of the photosensitive resin composition, but is preferably about 10 to 600 mJ / cm ² , for example.

  When the substrate is an element formed on a substrate such as a TFT substrate, a black column spacer is formed on the element or at a location facing the element on the substrate that is paired with the substrate on which the element is formed. There may be a need. In such a case, it is necessary to change the height of the black column spacer between the part where the element is formed and the other part in consideration of the height of the element. Therefore, in such a case, it is preferable to perform exposure through a halftone mask. By using the photosensitive resin composition according to the present invention, black column spacers having different heights can be easily formed by performing exposure through a halftone mask.

  Next, in the development step, the black column spacer is formed by developing the exposed photosensitive resin layer with a developer. The development method is not particularly limited, and an immersion method, a spray method, or the like can be used. Specific examples of the developer include organic ones such as monoethanolamine, diethanolamine, and triethanolamine, and aqueous solutions such as sodium hydroxide, potassium hydroxide, sodium carbonate, ammonia, and quaternary ammonium salts.

  Thereafter, the black column spacer after development is post-baked and cured by heating. Post baking is preferably performed at 150 to 250 ° C. for 15 to 60 minutes.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the scope of the present invention is not limited to these examples.

<Examples 1-3, Comparative Examples 1 and 2>
Each component shown in the following Table 1 was mixed and dissolved in a solvent so that the solid content was 20% by mass to prepare a photosensitive resin composition. The solvent was adjusted so that methoxybutyl acetate was 65% by mass, propylene glycol monomethyl ether acetate (PM) was 5% by mass, cyclohexanone was 25% by mass, and diethylene glycol methyl ether was 5% by mass. .

  In Table 1, each abbreviation indicates the following, and the numerical value in parentheses is the number of parts (parts by mass) of the solid content in the photosensitive resin composition.

(Alkali-soluble resin)
A-1: Resin obtained by the following production method (solid content 55%, solvent: 3-methoxybutyl acetate)
A-2: methacrylic acid / 3,4-epoxycyclohexan-1-ylmethyl methacrylate / tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate = 12/71/17 (mass ratio) ) Resin (mass average molecular weight 12000)
A-3: Methacrylic acid / 3,4-epoxycyclohexan-1-ylmethyl methacrylate / tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate = 14/70/16 (mass ratio) ) Resin (mass average molecular weight 8000)

(Photopolymerizable monomer)
DPHA: Dipentaerythritol hexaacrylate

(Photopolymerization initiator)
OXE02: Ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl], 1- (O-acetyloxime) ("IRGACURE OXE02" manufactured by BASF)

(Light-shielding agent)
AgSn dispersion: silver tin alloy fine particle dispersion (25% by mass of silver tin alloy fine particles having an average particle size of 200 to 300 nm, dispersant: 3.7% by mass of DPK-164 (manufactured by BYK Chemie), solvent: propylene glycol monomethyl ester Tail acetate)

In addition, the synthesis method of the said resin (A-1) is as follows.
First, in a 500 ml four-necked flask, 235 g of bisphenolfluorene type epoxy resin (epoxy equivalent 235), 110 mg of tetramethylammonium chloride, 100 mg of 2,6-di-tert-butyl-4-methylphenol, and 72.0 g of acrylic acid Was heated and dissolved at 90 to 100 ° C. while blowing air at a rate of 25 ml / min. Next, the temperature was gradually raised while the solution was clouded, and the solution was heated to 120 ° C. to be completely dissolved. At this time, the solution gradually became transparent and viscous, but stirring was continued as it was. During this time, the acid value was measured, and heating and stirring were continued until the acid value was less than 1.0 mgKOH / g. It took 12 hours for the acid value to reach the target value. And it cooled to room temperature and obtained the bisphenol fluorene type epoxy acrylate represented by the following transparent formula (a-4) colorless and transparent.

Next, after adding 600 g of 3-methoxybutyl acetate to 307.0 g of the bisphenolfluorene type epoxy acrylate thus obtained and dissolving, 80.5 g of benzophenonetetracarboxylic dianhydride and 1 g of tetraethylammonium bromide were added. The mixture was gradually heated and reacted at 110 to 115 ° C. for 4 hours. After confirming disappearance of the acid anhydride group, 38.0 g of 1,2,3,6-tetrahydrophthalic anhydride was mixed and reacted at 90 ° C. for 6 hours to obtain Resin (A-1). The disappearance of the acid anhydride group was confirmed by IR spectrum.
In addition, this resin (A-1) is corresponded to resin represented by the said Formula (a-1).

<Evaluation>
[OD value evaluation]
After coating the photosensitive resin compositions of Examples 1 to 3 and Comparative Examples 1 and 2 on a 6-inch glass substrate (Dow Corning, 1737 glass), the photosensitive resin was dried at 90 ° C. for 60 seconds. A layer was formed. Subsequently, this photosensitive resin layer was irradiated with ghi rays at an exposure amount of 60 mJ / cm ² . And it post-baked on the hotplate for 20 minutes at 230 degreeC. The thickness of the formed light shielding film was three levels of 0.8 μm, 1.0 μm, and 1.2 μm. About this light shielding film, OD value in each film thickness was measured using D200-II (made by Macbeth), and OD value per micrometer was computed with the approximated curve. The results are shown in Table 2.

[Evaluation of shape]
After coating the photosensitive resin compositions of Examples 1 to 3 and Comparative Examples 1 and 2 on a 6-inch glass substrate (1737 glass manufactured by Dow Corning), the film was dried at 90 ° C. for 60 seconds to obtain a film thickness. A photosensitive resin layer of 3.0 μm was formed. Next, this photosensitive resin layer was selectively irradiated with ghi rays through a negative mask having a mask size of 30 μm at an exposure amount of 50 mJ / cm ² , and 70% at 23 ° C. using 0.05 mass% KOH aqueous solution. A black column spacer was formed by spray development for 2 seconds. Thereafter, post-baking was performed on a hot plate at 230 ° C. for 20 minutes.
And the diameter B in the lowermost part of the black column spacer after post-baking and the diameter T in the vicinity of the uppermost part (thickness part of 95% from the lowermost part) were measured, and the T / B ratio was calculated by the following formula. The results are shown in Table 2.
T / B ratio = (T / B) × 100

[Evaluation of relative permittivity]
The photosensitive resin compositions of Examples 1 to 3 and Comparative Examples 1 and 2 were applied on a 6-inch silicon wafer, and then dried at 90 ° C. for 60 seconds to form a photosensitive resin layer. Subsequently, this photosensitive resin layer was irradiated with ghi rays at an exposure amount of 60 mJ / cm ² . And it post-baked on the hotplate for 20 minutes at 230 degreeC. The formed light shielding film had a thickness of 1.0 μm. About this light shielding film, the dielectric constant measurement apparatus SSM495 (made by SSM Japan) measured the relative dielectric constant (in 1 kHz) with respect to the vacuum of the light shielding film in the film thickness direction. The results are shown in Table 2.

[Evaluation of halftone (HT) characteristics]
After coating the photosensitive resin compositions of Examples 1 to 3 and Comparative Examples 1 and 2 on a 6-inch glass substrate (1737 glass manufactured by Dow Corning), the film was dried at 90 ° C. for 60 seconds to obtain a film thickness. A photosensitive resin layer of 3.0 μm was formed. Next, this photosensitive resin layer was selectively irradiated with ghi rays through a negative mask having a mask size of 30 μm. The exposure amount was 5 to 50 mJ / cm ² . Subsequently, the black column spacer was formed by spray development using 0.05 mass% KOH aqueous solution at 23 degreeC for 70 second (s). Thereafter, post-baking was performed on a hot plate at 230 ° C. for 20 minutes.
By obtaining the difference between the exposure amount 5 mJ / cm when the ² and 50 mJ / cm black column spacer after post-baking in the case of the ^second height, was used as an index of the halftone characteristics. The results are shown in Table 2.

[Evaluation of adhesion]
After coating the photosensitive resin compositions of Examples 1 to 3 and Comparative Examples 1 and 2 on a 6-inch glass substrate (1737 glass manufactured by Dow Corning), the film was dried at 90 ° C. for 60 seconds to obtain a film thickness. A photosensitive resin layer of 3.0 μm was formed. Next, this photosensitive resin layer is selectively irradiated with ghi rays through a negative mask at an exposure amount of 50 mJ / cm ² and spray-developed at 23 ° C. using a 0.05 mass% KOH aqueous solution. A black column spacer was formed. The development time was about 1.5 times the BP, based on the time until the unexposed area was completely dissolved (BP: break point). Thereafter, post-baking was performed on a hot plate at 230 ° C. for 20 minutes.
Then, the minimum mask dimension capable of forming the black column spacer was examined at an exposure amount of 50 mJ / cm ² and used as an adhesion index. The results are shown in Table 2.

As can be seen from Table 2, when the photosensitive resin compositions of Examples 1 to 3 containing a resin having a cardo structure and an epoxy resin were used, a black column having a good shape with a T / B ratio of 50 or more A spacer could be formed.
On the other hand, when the photosensitive resin composition of Comparative Example 1 containing a resin having a cardo structure and no epoxy resin is used, only a black column spacer having a very small T / B ratio of 29.1 is formed. I could not. In this case, since the area of the uppermost portion of the black column spacer is reduced, the strength of the spacer is insufficient, and a problem occurs in the quality of the display device.
When the photosensitive resin composition of Comparative Example 2 containing an epoxy resin and no cardo structure was used, a 30 μm diameter black column spacer could not be formed.

Claims (8)

Containing alkali-soluble resin, photopolymerizable monomer, photopolymerization initiator, and fine particles mainly composed of silver tin alloy,
A photosensitive resin composition for a black column spacer, wherein the alkali-soluble resin includes a resin having a cardo structure and an epoxy resin.   The photosensitive resin composition for a black column spacer according to claim 1, wherein a ratio of the resin having a cardo structure and the epoxy resin is 99: 1 to 1:99 on a mass basis.   Furthermore, the photosensitive resin composition for black column spacers of Claim 1 or 2 containing a light absorber. A photosensitive resin layer having a film thickness of 3.0 μm made of the photosensitive resin composition for black column spacers is exposed to ghi rays at an exposure amount of 50 mJ / cm ² , and subsequently, a 0.05 mass% KOH aqueous solution is added. After developing at 23 ° C. for 70 seconds and performing post-baking at 230 ° C. for 20 minutes, a black column spacer having a diameter of 25 to 35 μm was obtained. The photosensitive resin composition for black column spacers according to any one of claims 1 to 3, wherein a diameter T at a film thickness portion of 95% from the bottom satisfies a relational expression of (T / B) x 100> 50 .   The black column spacer formed from the photosensitive resin composition for black column spacers of any one of Claim 1 to 4.   A display device comprising the black column spacer according to claim 5. An application step of applying the photosensitive resin composition for a black column spacer according to any one of claims 1 to 4 on a substrate to form a photosensitive resin layer;
An exposure step of exposing the photosensitive resin layer according to a pattern of a predetermined black column spacer;
And developing a photosensitive resin layer after the exposure to form a black column spacer pattern.   The method for forming a black column spacer according to claim 7, wherein in the exposure step, exposure is performed through a halftone mask.