JP4501665B2 - Photosensitive resin composition - Google Patents

Description

  The present invention relates to a photosensitive resin composition.

  The present invention relates to a photosensitive resin composition. More specifically, a material for forming a transparent film constituting a part of the color filter, for example, an overcoat, a photo spacer, an insulating film, a liquid crystal alignment control protrusion, a coat layer for adjusting the thickness of the colored pattern, etc. The present invention relates to a photosensitive resin composition suitable for forming a transparent film, a color filter including the transparent film, and a liquid crystal display device including the color filter.

A spacer is provided between the color filter constituting the display device, such as a liquid crystal display device or a touch panel, and the array substrate in order to keep the distance between the two substrates. Conventionally, spherical particles such as glass beads and plastic beads are used for this spacer.
However, when such spherical particles are used, the spherical particles are randomly distributed on the glass substrate, resulting in damage to TFT elements and electrodes, or when the spherical particles are present in the transmissive pixel portion, the incident light In some cases, the contrast of the liquid crystal display element may be reduced due to the scattering of light. Therefore, it has been proposed to form spacers with a photosensitive resin instead of using spherical particles. According to this method, since the spacer can be formed at an arbitrary place, the above-mentioned problems can be solved.
As such a photosensitive resin, a spacer forming composition containing a binder resin made of an acrylic copolymer having an epoxy group represented by a carboxyl group and a glycidyl ether group is known (Patent Document 1). During post-baking after development in the spacer forming step, the epoxy group and the carboxyl group are cross-linked, and a spacer pattern having excellent solvent resistance and heat resistance can be obtained.

JP-A-11-133600, page 2, left column, line 2-page 2, left column, line 9

However, depending on the photosensitive resin composition, the resulting spacer has good coating film properties, but if the composition is stored for a long period of time, thickening or gelation of the composition may occur. For example, according to the study of the present inventor, even a resin having an aliphatic monocyclic epoxy group as a constituent component, which is said to have better stability than a resin having an epoxy group such as a glycidyl group as a constituent component, It has been found that the storage stability is still insufficient even with the photosensitive resin composition containing the same.
Accordingly, an object of the present invention is to provide a photosensitive resin composition that can form a pattern or a coating film that has a small change in viscosity during storage, can be resolved to a fine pattern, and has excellent solvent resistance and heat resistance. For the purpose.

As a result of intensive studies on new means that can solve the above-mentioned problems, the present inventor has found that the photosensitive resin composition of the present invention can solve the above-mentioned problems, leading to the present invention.
That is, the present invention relates to a photosensitive resin composition containing a binder resin (A), a photopolymerizable compound (B), a photopolymerization initiator (C) and a solvent (D), wherein the binder resin (A) is unsaturated. Carboxylic acid and / or unsaturated carboxylic acid anhydride (A1), compound (A2) having a polycyclic aliphatic group having an epoxy group on the ring and a group having an unsaturated bond, and the above are polymerized ( Provided is a photosensitive resin composition that is a copolymer with monomers (A1) and (A2) (A3) that are copolymerizable with (A1) and (A2).
Moreover, this invention provides the liquid crystal display device containing the pattern formed using the said photosensitive resin composition, and the said pattern.

  The photosensitive resin composition of the present invention has a small viscosity change during storage, can be resolved to a fine pattern, and can form a coating film excellent in solvent resistance and heat resistance.

  Hereinafter, the present invention will be described in detail.

  The photosensitive resin composition of the present invention is mainly used as a pattern forming material, and includes a binder resin (A), a photopolymerizable compound (B) and a photopolymerization initiator (C), and optionally other. The additive (F) is dissolved or dispersed in the solvent (D).

  The binder resin (A) used in the photosensitive resin composition of the present invention has alkali solubility, and has an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride (A1) and an epoxy group on the ring. Compound (A2) having a polycyclic aliphatic group having an unsaturated bond group and a monomer copolymerizable with (A1) and (A2) (excluding (A1) and (A2)) .) A copolymer with (A3).

Specific examples of the unsaturated carboxylic acid and / or unsaturated carboxylic acid anhydride (A1) include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid;
Unsaturated dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid;
And anhydrides of the aforementioned unsaturated dicarboxylic acids;
Unsaturated mono [(meth) acryloyloxy of polyvalent carboxylic acids such as succinic acid mono [2- (meth) acryloyloxyethyl] and phthalic acid mono [2- (meth) acryloyloxyethyl] Alkyl] esters;
Examples thereof include unsaturated acrylates containing a hydroxy group and a carboxyl group in the same molecule, such as α- (hydroxymethyl) acrylic acid.
Of these, acrylic acid, methacrylic acid, maleic anhydride and the like are preferably used from the viewpoint of copolymerization reactivity and solubility in an alkaline aqueous solution. These may be used alone or in combination.

In the compound (A2) having a polycyclic aliphatic group having an epoxy group on the ring and a group having an unsaturated bond, the polycyclic aliphatic group may be a dicyclopentanyl group or a tricyclodecyl group. Etc. Moreover, a vinyl group is mentioned as said unsaturated bond.
The compound (A2) having a polycyclic aliphatic group having an epoxy group on the ring and a group having an unsaturated bond is preferably a compound represented by the formula (I) and a formula (II). Examples include at least one compound selected from the group consisting of compounds.

[In formula (I) and formula (II), R represents a C1-C4 alkyl group which may be substituted by the hydrogen atom or the hydroxyl group each independently.
X represents each independently a C1-C6 alkylene group which may contain a single bond or a hetero atom. ]

Specific examples of R include alkyl groups such as hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, and tert-butyl group;
Hydroxymethyl group, 1-hydroxyethyl group, 2-hydroxyethyl group, 1-hydroxy-n-propyl group, 2-hydroxy-n-propyl group, 3-hydroxy-n-propyl group, 1-hydroxy-isopropyl group, And hydroxyl group-containing alkyl groups such as 2-hydroxy-isopropyl group, 1-hydroxy-n-butyl group, 2-hydroxy-n-butyl group, 3-hydroxy-n-butyl group and 4-hydroxy-n-butyl group. It is done. Among these, Preferably a hydrogen atom, a methyl group, a hydroxymethyl group, 1-hydroxyethyl group, 2-hydroxyethyl group is mentioned, More preferably, a hydrogen atom and a methyl group are mentioned.

X represents a single bond or an alkylene group such as a methylene group, an ethylene group or a propylene group;
Examples thereof include heteroatom-containing alkylene groups such as oxymethylene group, oxyethylene group, oxypropylene group, thiomethylene group, thioethylene group, thiopropylene group, aminomethylene group, aminoethylene group, and aminopropylene group. Of these, a single bond, a methylene group, an ethylene group, an oxymethylene group, and an oxyethylene group are preferable, and a single bond and an oxyethylene group are more preferable.

  Examples of the compound represented by the formula (I) include compounds represented by the formula (I-1) to the formula (I-15), preferably the formula (I-1) and the formula (I-3). , Formula (I-5), formula (I-7), formula (I-9), formula (I-11) to formula (I-15), and more preferably formula (I-1), formula (I-7), Formula (I-9), and Formula (I-15) are mentioned.

  Examples of the compound represented by the formula (II) include compounds represented by the formula (II-1) to the formula (II-15), preferably the formula (II-1) and the formula (II-3). , Formula (II-5), formula (II-7), formula (II-9), formula (II-11) to formula (II-15), more preferably formula (II-1), (II-7), Formula (II-9), and Formula (II-15) are mentioned.

  At least one compound selected from the group consisting of the compound represented by formula (I) and the compound represented by formula (II) can be used alone. They can also be mixed in any ratio. In the case of mixing, the mixing ratio is a molar ratio, preferably 5:95 to 95: 5, more preferably 10:90 to 90:10, particularly preferably 20:80 in the formula (I): formula (II). ~ 80: 20.

As the monomer (A3) copolymerizable with (A1) and (A2) (excluding (A1) and (A2)), methyl (meth) acrylate, ethyl (meth) acrylate, (meth) acrylic acid alkyl esters such as n-butyl (meth) acrylate, sec-butyl (meth) acrylate and t-butyl (meth) acrylate;
Alkyl acrylates such as methyl acrylate and isopropyl acrylate;
Cyclohexyl (meth) acrylate, 2-methylcyclohexyl (meth) acrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl (meth) acrylate (in this technical field, dicyclopenta Nyl (meth) acrylate), (meth) acrylic acid cyclic alkyl esters such as dicyclopentanyloxyethyl (meth) acrylate, isoboronyl (meth) acrylate;
Cyclohexyl acrylate, 2-methylcyclohexyl acrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl acrylate (commonly referred to in the art as dicyclopentanyl acrylate), dicyclo Acrylic acid cyclic alkyl esters such as pentaoxyethyl acrylate and isobornyl acrylate;
(Meth) acrylic acid aryl esters such as phenyl (meth) acrylate and benzyl (meth) acrylate;
Acrylic acid aryl esters such as phenyl acrylate and benzyl acrylate;
Dicarboxylic acid diesters such as diethyl maleate, diethyl fumarate, diethyl itaconate;
Hydroxyalkyl esters such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate;
Bicyclo [2.2.1] hept-2-ene, 5-methylbicyclo [2.2.1] hept-2-ene, 5-ethylbicyclo [2.2.1] hept-2-ene, 5- Hydroxybicyclo [2.2.1] hept-2-ene, 5-carboxybicyclo [2.2.1] hept-2-ene, 5-hydroxymethylbicyclo [2.2.1] hept-2-ene, 5- (2′-hydroxyethyl) bicyclo [2.2.1] hept-2-ene, 5-methoxybicyclo [2.2.1] hept-2-ene, 5-ethoxybicyclo [2.2.1 ] Hept-2-ene, 5,6-dihydroxybicyclo [2.2.1] hept-2-ene, 5,6-dicarboxybicyclo [2.2.1] hept-2-ene, 5,6- Di (hydroxymethyl) bicyclo [2.2.1] hept-2-e 5,6-di (2′-hydroxyethyl) bicyclo [2.2.1] hept-2-ene, 5,6-dimethoxybicyclo [2.2.1] hept-2-ene, 5,6 -Diethoxybicyclo [2.2.1] hept-2-ene, 5-hydroxy-5-methylbicyclo [2.2.1] hept-2-ene, 5-hydroxy-5-ethylbicyclo [2.2 .1] Hept-2-ene, 5-carboxy-5-methylbicyclo [2.2.1] hept-2-ene, 5-carboxy-5-ethylbicyclo [2.2.1] hept-2-ene 5-hydroxymethyl-5-methylbicyclo [2.2.1] hept-2-ene, 5-carboxy-6-methylbicyclo [2.2.1] hept-2-ene, 5-carboxy-6- Ethylbicyclo [2.2.1] hept-2-ene, 5, 6-dicarboxybicyclo [2.2.1] hept-2-ene anhydride (hymic acid anhydride), 5-t-butoxycarbonylbicyclo [2.2.1] hept-2-ene, 5-cyclohexyloxy Carbonylbicyclo [2.2.1] hept-2-ene, 5-phenoxycarbonylbicyclo [2.2.1] hept-2-ene, 5,6-di (t-butoxycarbonyl) bicyclo [2.2. 1] Bicyclo unsaturated compounds such as hept-2-ene and 5,6-di (cyclohexyloxycarbonyl) bicyclo [2.2.1] hept-2-ene;
N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, N-succinimidyl-3-maleimidobenzoate, N-succinimidyl-4-maleimidobutyrate, N-succinimidyl-6-maleimidocaproate, N-succinimidyl-3 -Dicarbonylimide derivatives such as maleimide propionate, N- (9-acridinyl) maleimide;
Styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, vinyl toluene, p-methoxystyrene, acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, acrylamide, methacrylamide, vinyl acetate, 1,3-butadiene , Isoprene, 2,3-dimethyl-1,3-butadiene, glycidyl acrylate, glycidyl methacrylate, glycidyl α-ethyl acrylate, glycidyl α-n-propyl acrylate, glycidyl α-n-butyl acrylate, acrylic acid -3,4-epoxybutyl, methacrylic acid-3,4-epoxybutyl, acrylic acid-6,7-epoxyheptyl, methacrylic acid-6,7-epoxyheptyl, α-ethylacrylic acid-6,7-epoxyheptyl , O-Vinylbenzylglycidyl A Le, m- vinylbenzyl glycidyl ether, p- vinylbenzyl glycidyl ether.
Of these, styrene, N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, bicyclo [2.2.1] hept-2-ene and the like are preferable from the viewpoint of copolymerization reactivity and solubility in an aqueous alkali solution. .
These may be used alone or in combination.

The binder resin (A) used in the present invention is a copolymer obtained by copolymerizing (A1), (A2) and (A3), and the ratio of the constituent components derived from each is the above-mentioned copolymer. It is preferably in the following range in terms of mole fraction with respect to the total number of moles of the constituent components constituting the polymer.
Structural units derived from (A1); 2 to 40 mol%
Structural units derived from (A2); 2 to 95 mol%
Structural units derived from (A3); 1 to 65 mol%

Moreover, it is more preferable in the ratio of the said structural component being the following ranges.
Structural units derived from (A1); 5-35 mol%
Structural units derived from (A2); 5 to 80 mol%
Structural units derived from (A3); 1-60 mol%
When the composition ratio is in the above range, storage stability, developability, solvent resistance, heat resistance and mechanical strength tend to be good.

The binder resin (A) is, for example, a method described in the document “Experimental Method for Polymer Synthesis” (Takayuki Otsu, published by Kagaku Dojin Co., Ltd., First Edition, First Edition, issued March 1, 1972). And it can manufacture with reference to the cited reference described in the said literature.
Specifically, a predetermined amount of a compound that leads to the units (A1), (A2), and (A3) constituting the copolymer, a polymerization initiator, and a solvent are charged into a reaction vessel, and oxygen is substituted with nitrogen. Thus, a polymer can be obtained by stirring, heating and heat-retaining in the absence of oxygen. In addition, the obtained copolymer may use the solution after the reaction as it is, may use a concentrated or diluted solution, and was taken out as a solid (powder) by a method such as reprecipitation. You may use things.

The weight average molecular weight in terms of polystyrene of the binder resin (A) is preferably 3,000 to 100,000, more preferably 5,000 to 50,000. When the weight average molecular weight of the binder resin (A) is in the above range, the coating property tends to be good, the film is not easily reduced during development, and the non-pixel portion is easily removed during development. It tends to be preferable.
The molecular weight distribution [weight average molecular weight (Mw) / number average molecular weight (Mn)] of the binder resin (A) is preferably 1.1 to 6.0, and more preferably 1.2 to 4.0. The molecular weight distribution in the above range is preferable because it tends to be excellent in developability.
Content of binder resin (A) used for the photosensitive resin composition of this invention is a mass fraction with respect to solid content in the photosensitive resin composition, Preferably it is 5-90 mass%, More preferably, it is 10 -70 mass%. When the content of the binder resin (A) is in the above range, the solubility in the developer is sufficient, and a development residue is hardly generated on the non-pixel portion of the substrate. This is preferable because the film loss is less likely to occur, and the non-pixel portion is liable to be removed.

The photopolymerizable compound (B) contained in the photosensitive resin composition of the present invention can be a monofunctional monomer, a bifunctional monomer, or another polyfunctional monomer having three or more functions.
Specific examples of the monofunctional monomer include nonylphenyl carbitol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-ethylhexyl carbitol acrylate, 2-hydroxyethyl acrylate, N-vinyl pyrrolidone and the like.
Specific examples of the bifunctional monomer include 1,6-hexanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and bisphenol A. Bis (acryloyloxyethyl) ether, 3-methylpentanediol di (meth) acrylate, and the like.
Specific examples of other trifunctional or higher polyfunctional monomers include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, di Examples include pentaerythritol hexa (meth) acrylate, a reaction product of pentaerythritol tri (meth) acrylate and an acid anhydride, a reaction product of dipentaerythritol penta (meth) acrylate and an acid anhydride, and the like. Of these, polyfunctional monomers having two or more functions are preferably used. These photopolymerizable compounds (B) can be used alone or in combination of two or more.
Content of a photopolymerizable compound (B) is a mass fraction with respect to the total amount of binder resin (A) and a photopolymerizable compound (B), Preferably it is 1-70 mass%, More preferably, it is 5-60. % By mass. When the content of the photopolymerizable compound (B) is in the above range, the strength, smoothness, and reliability of the pixel portion tend to be favorable, which is preferable.

  The photopolymerization initiator (C) contained in the photosensitive resin composition of the present invention is preferably an acetophenone-based, biimidazole-based, oxime-based, triazine-based, or acylphosphine oxide-based initiator. When the photopolymerization initiator auxiliary agent (C-1) is used in combination with these photopolymerization initiators (C), the resulting photosensitive resin composition has a higher sensitivity. This is preferable because the productivity of the pattern is improved.

  Examples of the acetophenone compounds include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, and 2-hydroxy-1- [4- (2-hydroxyethoxy) phenyl]. 2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butan-1-one, 2- (2-methylbenzyl) -2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2- (3-methylbenzyl) -2-dimethylamino -1- (4-morpholinophenyl) -butanone, 2- (4-methylbenzyl) -2-dimethyl Amino-1- (4-morpholinophenyl) -butanone, 2- (2-ethylbenzyl) -2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2- (2-propylbenzyl) -2-dimethyl Amino-1- (4-morpholinophenyl) -butanone, 2- (2-butylbenzyl) -2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2- (2,3-dimethylbenzyl) -2 -Dimethylamino-1- (4-morpholinophenyl) -butanone, 2- (2,4-dimethylbenzyl) -2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2- (2-chlorobenzyl) 2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2- (2-bromobenzyl) -2-dimethylamino-1- (4-moly Holinophenyl) -butanone, 2- (3-chlorobenzyl) -2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2- (4-chlorobenzyl) -2-dimethylamino-1- (4-morpholino Phenyl) -butanone, 2- (3-bromobenzyl) -2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2- (4-bromobenzyl) -2-dimethylamino-1- (4-morpholino) Phenyl) -butanone, 2- (2-methoxybenzyl) -2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2- (3-methoxybenzyl) -2-dimethylamino-1- (4-morpholino) Phenyl) -butanone, 2- (4-methoxybenzyl) -2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2 -(2-Methyl-4-methoxybenzyl) -2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2- (2-methyl-4-bromobenzyl) -2-dimethylamino-1- (4 -Morpholinophenyl) -butanone, 2- (2-bromo-4-methoxybenzyl) -2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2-hydroxy-2-methyl-1- [4- ( 1-methylvinyl) phenyl] propan-1-one oligomer and the like.

  Examples of the biimidazole compound include 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole and 2,2′-bis (2,3-dichlorophenyl) -4. , 4 ′, 5,5′-tetraphenylbiimidazole (see, for example, JP-A-6-75372 and JP-A-6-75373), 2,2′-bis (2-chlorophenyl) -4, 4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetra (alkoxyphenyl) biimidazole, 2,2′-bis ( 2-chlorophenyl) -4,4 ′, 5,5′-tetra (dialkoxyphenyl) biimidazole, 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetra (trialkoxy) Phenyl) biimidazole (for example, see JP-B-48-38403, JP-A-62-174204, etc.), and the phenyl group at the 4,4′5,5′-position is substituted with a carboalkoxy group. Imidazole compounds (see, for example, JP-A-7-10913) and the like, preferably 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (2,3-dichlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole may be mentioned. In addition

  Examples of the oxime compound include O-ethoxycarbonyl-α-oximino-1-phenylpropan-1-one, a compound represented by formula (3), a compound represented by formula (4), and the like.

  Examples of the triazine compound include 2,4-bis (trichloromethyl) -6- (4-methoxyphenyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (4- Methoxynaphthyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6-piperonyl-1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (4-methoxy Styryl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (5-methylfuran-2-yl) ethenyl] -1,3,5-triazine, 2,4 -Bis (trichloromethyl) -6- [2- (furan-2-yl) ethenyl] -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (4-diethylamino- 2-methylphenyl) Thenyl] -1,3,5-triazine, such as 2,4-bis (trichloromethyl) -6- [2- (3,4-dimethoxyphenyl) ethenyl] -1,3,5-triazine.

  Examples of the acylphosphine oxide initiator include 2,4,6-trimethylbenzoyldiphenylphosphine oxide.

Moreover, as long as the effects of the present invention are not impaired, a photopolymerization initiator or the like usually used in this field can be further used together. Examples of the photopolymerization initiator include benzoin compounds and benzophenones. Compounds, thioxanthone compounds, anthracene compounds, and the like.
More specifically, the following compounds can be mentioned, and these can be used alone or in combination of two or more.

  Examples of the benzoin-based compound include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether.

  Examples of the benzophenone compounds include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4′-methyldiphenyl sulfide, 3,3 ′, 4,4′-tetra (tert-butyl). Peroxycarbonyl) benzophenone, 2,4,6-trimethylbenzophenone, and the like.

  Examples of the thioxanthone compound include 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, and the like.

  Examples of the anthracene compound include 9,10-dimethoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, and 2-ethyl-9,10-diethoxyanthracene. It is done.

  Other examples of the photopolymerization initiator include 10-butyl-2-chloroacridone, 2-ethylanthraquinone, benzyl, 9,10-phenanthrenequinone, camphorquinone, methyl phenylglyoxylate, and titanocene compounds. .

Further, as a photopolymerization initiator having a group capable of causing chain transfer, a photopolymerization initiator described in JP-T-2002-544205 can be used.
As a photoinitiator which has the group which can raise | generate the said chain transfer, the photoinitiator of following formula (5)-(10) is mentioned, for example.

  The photopolymerization initiator having a group capable of causing chain transfer can also be used as the constituent component (A3) of the copolymer. And the obtained copolymer can be used for binder resin used as binder resin of the photosensitive resin composition of this invention, and can also be used together.

Moreover, a photoinitiator (C-1) can also be used in combination with a photoinitiator. As the photopolymerization initiation assistant, an amine compound and the following carboxylic acid compound are preferable, and the amine compound is more preferably an aromatic amine compound.
Specific examples of the photopolymerization initiation aid include aliphatic amine compounds such as triethanolamine, methyldiethanolamine, triisopropanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, 4-dimethylaminobenzoic acid. Isoamyl, 2-dimethylhexyl 4-dimethylaminobenzoate, 2-dimethylaminoethyl benzoate, N, N-dimethylparatoluidine, 4,4′-bis (dimethylamino) benzophenone (common name: Michler's ketone), 4,4′- Examples include aromatic amine compounds such as bis (diethylamino) benzophenone.
Examples of the carboxylic acid compound include phenylthioacetic acid, methylphenylthioacetic acid, ethylphenylthioacetic acid, methylethylphenylthioacetic acid, dimethylphenylthioacetic acid, methoxyphenylthioacetic acid, dimethoxyphenylthioacetic acid, chlorophenylthioacetic acid, dichlorophenylthioacetic acid, Examples include aromatic heteroacetic acids such as N-phenylglycine, phenoxyacetic acid, naphthylthioacetic acid, N-naphthylglycine, and naphthoxyacetic acid.

Content of a photoinitiator (C) is a mass fraction with respect to the total amount of binder resin (A) and a photopolymerizable compound (B), Preferably it is 0.1-40 mass%, More preferably, it is 1 -30 mass%.
The content of the photopolymerization initiation assistant (C-1) is preferably 0.01 to 50% by mass, more preferably 0.1 to 40% by mass, based on the same standard as described above.
When the total amount of the photopolymerization initiator (C) is in the above range, the photosensitive resin composition becomes highly sensitive, and the strength of the pixel portion formed using the photosensitive resin composition, The smoothness on the surface tends to be good, which is preferable. In addition to the above, when the amount of the photopolymerization initiation assistant (C-1) is in the above range, the sensitivity of the obtained photosensitive resin composition is further increased, and the photosensitive resin composition is formed using the photosensitive resin composition. This is preferable because the productivity of the patterned substrate tends to be improved.

The photosensitive resin composition of the present invention contains a solvent (D). The solvent (D) can be various organic solvents used in the field of photosensitive resin compositions. Specific examples thereof include ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether and ethylene glycol monobutyl ether;
Diethylene glycol dialkyl ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether and diethylene glycol dibutyl ether;
Ethylene glycol alkyl ether acetates such as methyl cellosolve acetate and ethyl cellosolve acetate;
Alkylene glycol alkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methoxybutyl acetate and methoxypentyl acetate;
Aromatic hydrocarbons such as benzene, toluene, xylene and mesitylene;
Ketones such as methyl ethyl ketone, acetone, methyl amyl ketone, methyl isobutyl ketone and cyclohexanone;
Alcohols such as ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol and glycerin;
Esters such as ethyl 3-ethoxypropionate and methyl 3-methoxypropionate;
and cyclic esters such as γ-butyrolactone.
Among the above-mentioned solvents, from the viewpoints of coating properties and drying properties, an organic solvent having a boiling point of 100 ° C. to 200 ° C. is preferable among the solvents, and more preferably alkylene glycol alkyl ether acetates, ketones, And esters such as ethyl 3-ethoxypropionate and methyl 3-methoxypropionate, particularly preferably propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, cyclohexanone, ethyl 3-ethoxypropionate and 3-methoxy And methyl propionate.
These solvents (D) can be used alone or in admixture of two or more.
Content of the solvent (D) in the photosensitive resin composition of this invention is a mass fraction with respect to the photosensitive resin composition, Preferably it is 60-90 mass%, More preferably, it is 70-85 mass%. When the content of the solvent (D) is within the above range, when applied by a spin coater, slit & spin coater, slit coater (sometimes called a die coater or curtain flow coater), an ink jet or the like. The coating property is expected to be good, and is preferable.

In the photosensitive resin composition of the present invention, a filler, other polymer compound, a pigment dispersant, an adhesion promoter, an antioxidant, an ultraviolet absorber, an anti-aggregating material, an aggregating agent, and chain transfer are optionally included. An additive (F) such as an agent can also be used in combination.
Specific examples of the filler include glass, silica, and alumina.
Specific examples of other polymer compounds include curable resins such as epoxy resins and maleimide resins, and thermoplastic resins such as polyvinyl alcohol, polyacrylic acid, polyethylene glycol monoalkyl ether, polyfluoroalkyl acrylate, polyester, and polyurethane. Can be used.
Commercially available surfactants can be used as the pigment dispersant, and examples include silicone-based, fluorine-based, ester-based, cationic-based, anionic-based, nonionic-based, and amphoteric surfactants. Or a combination of two or more. Examples of the surfactant include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyethylene glycol diesters, sorbitan fatty acid esters, fatty acid-modified polyesters, tertiary amine-modified polyurethanes, and polyethyleneimines. In addition, KP (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow (manufactured by Kyoei Chemical Co., Ltd.), F-Top (manufactured by Tochem Products), MegaFuck (manufactured by Dainippon Ink & Chemicals, Inc.) ), FLORARD (manufactured by Sumitomo 3M Co., Ltd.), Asahi Guard, Surflon (manufactured by Asahi Glass Co., Ltd.), Solsperse (manufactured by Geneca Corporation), EFKA (manufactured by EFKA CHEMICALS), PB821 (manufactured by Ajinomoto Co., Inc.) ) And the like.
Specific examples of the adhesion promoter include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2- Aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) Examples include ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, and 3-mercaptopropyltrimethoxysilane.
Specific examples of the antioxidant include 2,2′-thiobis (4-methyl-6-tert-butylphenol) and 2,6-di-tert-butyl-4-methylphenol.
Specific examples of the ultraviolet absorber include 2- (3-tert-butyl-2-hydroxy-5-methylphenyl) -5-chlorobenzotriazole and alkoxybenzophenone.
Specific examples of the flocculant include sodium polyacrylate.
Examples of the chain transfer agent include dodecyl mercaptan and 2,4-diphenyl-4-methyl-1-pentene.

  For example, the photosensitive resin composition can be applied onto a substrate as described below, and can be photocured and developed to form a pattern. First, this composition is applied onto a substrate (usually glass) or a layer made of a solid content of a previously formed photosensitive resin composition, and prebaked from the applied photosensitive resin composition layer to obtain a solvent or the like. The volatile components are removed to obtain a smooth coating film. At this time, the thickness of the coating film is about 1 to 6 μm. The coating film thus obtained is irradiated with ultraviolet rays through a mask for forming a target pattern. At this time, it is preferable to use an apparatus such as a mask aligner or a stepper so that the entire exposed portion is uniformly irradiated with parallel light rays and the mask and the substrate are accurately aligned. Thereafter, the cured coating film is brought into contact with an alkaline aqueous solution to dissolve the non-exposed portion and developed, whereby the intended pattern shape is obtained. The developing method may be any of a liquid piling method, a dipping method, a spray method, and the like. Further, the substrate may be tilted at an arbitrary angle during development.

The developer used for development after patterning exposure is usually an aqueous solution containing an alkaline compound and a surfactant.
The alkaline compound may be either an inorganic or organic alkaline compound. Specific examples of the inorganic alkaline compound include sodium hydroxide, potassium hydroxide, disodium hydrogen phosphate, sodium dihydrogen phosphate, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, potassium dihydrogen phosphate, sodium silicate, potassium silicate, Examples thereof include sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, sodium borate, potassium borate, and ammonia.
Specific examples of the organic alkaline compound include tetramethylammonium hydroxide, 2-hydroxyethyltrimethylammonium hydroxide, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, and ethanolamine. Etc. These inorganic and organic alkaline compounds can be used alone or in combination of two or more. The concentration of the alkaline compound in the alkaline developer is preferably 0.01 to 10% by mass, more preferably 0.03 to 5% by mass.

The surfactant in the alkaline developer may be any of a nonionic surfactant, an anionic surfactant, or a cationic surfactant.
Specific examples of nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene aryl ether, polyoxyethylene alkyl aryl ether, other polyoxyethylene derivatives, oxyethylene / oxypropylene block copolymers, sorbitan fatty acid esters, polyoxyethylene Examples thereof include oxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, glycerin fatty acid ester, polyoxyethylene fatty acid ester, and polyoxyethylene alkylamine.
Specific examples of anionic surfactants include higher alcohol sulfate salts such as sodium lauryl alcohol sulfate and sodium oleyl alcohol sulfate, alkyl sulfates such as sodium lauryl sulfate and ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, And alkyl aryl sulfonates such as sodium dodecyl naphthalene sulfonate.
Specific examples of the cationic surfactant include amine salts or quaternary ammonium salts such as stearylamine hydrochloride and lauryltrimethylammonium chloride.
These surfactants can be used alone or in combination of two or more.
The concentration of the surfactant in the alkali developer is preferably in the range of 0.01 to 10% by mass, more preferably 0.05 to 8% by mass, and more preferably 0.1 to 5% by mass.

  After the development, it is washed with water, and further post-baked at 150 to 230 ° C. for 10 to 60 minutes, if necessary.

  By using the photosensitive resin composition of the present invention, a pattern can be formed on the substrate or the color filter substrate through the above steps. This pattern is useful as a photospacer used in a liquid crystal display device. Moreover, if a photomask for hole formation is used in patterning exposure to a dry coating film, a hole can be formed and it is useful as an interlayer insulation film. Furthermore, when exposing to a dry coating film, a transparent film can be formed only by full exposure and heat curing, or heat curing without using a photomask, and this transparent film is useful as an overcoat, It can also be used for a touch panel.

Therefore, by incorporating the pattern thus obtained into a display device such as a liquid crystal display device, an excellent quality display device can be manufactured with a high yield.

  Although the embodiments of the present invention have been described above, the embodiments of the present invention disclosed above are merely examples, and the scope of the present invention is not limited to these embodiments. The scope of the present invention is defined by the terms of the claims, and includes the meaning equivalent to the description of the claims and all modifications within the scope.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited by these Examples. In the examples, “%” and “part” representing the content or amount used are based on mass unless otherwise specified.

Synthesis example 1
In a 1 L flask equipped with a reflux condenser, a dropping funnel and a stirrer, nitrogen was allowed to flow at 0.02 L / min to form a nitrogen atmosphere, and 200 parts by mass of 3-methoxy-1-butanol and 105 parts by mass of 3-methoxybutyl acetate were added. And heated to 70 ° C. with stirring. Subsequently, 55 parts by mass of methacrylic acid, 3,4-epoxytricyclo [5.2.1.0 ^2.6 ] decyl acrylate (a compound represented by the formula (I-1) and a formula (II-1) The compound to be mixed is mixed at a molar ratio of 50:50.) A solution is prepared by dissolving 175 parts by mass and 70 parts by mass of N-cyclohexylmaleimide in 140 parts by mass of 3-methoxybutyl acetate. Then, it was dropped into a flask kept at 70 ° C. for 4 hours using a dropping pump. On the other hand, a solution obtained by dissolving 30 parts by mass of a polymerization initiator 2,2′-azobis (2,4-dimethylvaleronitrile) in 225 parts by mass of 3-methoxybutyl acetate was added to a flask over another 5 hours using another dropping pump. It was dripped in. After completion of the dropwise addition of the polymerization initiator solution, the temperature was maintained at 70 ° C. for 4 hours, and then cooled to room temperature. Viscosity (23 ° C.) 114 mPa · s, solid content 32.6% by mass, acid value 34.3 mg A solution of -KOH / g copolymer (resin Aa) was obtained. The obtained resin Aa had a weight average molecular weight Mw of 13,600 and a dispersity of 2.54.
The viscosity of the copolymer solution was measured with a B-type viscometer.

Synthesis example 2
The same operation as in Synthesis Example 1 of JP-A-11-133600 was performed to obtain a resin Ab.

Synthesis example 3
3,4-Epoxytricyclo [5.2.1.0 ^2.6 ] decyl acrylate (Compound represented by Formula (I-1) and Compound represented by Formula (II-1) of Synthesis Example 1 Are mixed in a molar ratio of 50:50) to 3,4-epoxycyclohexylmethyl methacrylate, and the same operation is carried out to obtain a viscosity (23 ° C.) of 120 mPa · s and a solid content of 32.8 mass. %, An acid value of 36.2 mg-KOH / g copolymer (resin Ac) was obtained. The obtained resin Ac had a weight average molecular weight Mw of 13,900 and a dispersity of 2.55.

The weight average molecular weight (Mw) and number average molecular weight (Mn) of the binder polymer were measured using the GPC method under the following conditions.
Apparatus; K2479 (manufactured by Shimadzu Corporation)
Column; SHIMADZU Shim-pack GPC-80M
Column temperature: 40 ° C
Solvent; THF (tetrahydrofuran)
Flow rate: 1.0 ml / min
Detector; RI
The ratio of the weight average molecular weight and the number average molecular weight obtained in the above-mentioned manner as polystyrene was defined as the dispersity (Mw / Mn).

Example 1
Resin solution part containing resin Aa obtained in Synthesis Example 1 (solid content 60 parts), dipentaerythritol hexaacrylate 40 parts, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one 6 parts, 53 parts of propylene glycol monomethyl ether acetate, 20 parts of 3-ethoxyethyl propionate, 37 parts of 3-methoxy 1-butanol and 87 parts of 3-methoxybutyl acetate were mixed to obtain photosensitive resin composition 1. .

A 2-inch square glass substrate (# 1737; manufactured by Corning) was sequentially washed with a neutral detergent, water and alcohol and then dried. On this glass substrate, the photosensitive resin composition 1 is exposed at an exposure amount (365 nm) of 100 mJ / cm ² , spin-coated so that the film thickness after development, water washing, and post-baking becomes 3.0 μm, Next, it was pre-baked at 100 ° C. for 3 minutes in a clean oven. After cooling, the distance between the substrate coated with the photosensitive resin composition and the quartz glass photomask was set to 50 μm, and an exposure machine (TME-150RSK; manufactured by Topcon Co., Ltd.) was used. Light was irradiated with an exposure amount of ² (based on 365 nm).
In addition, the photomask in which the following pattern was formed on the same plane was used as the photomask.

-It has a square translucent part (pattern) whose one side is 10 μm, and the interval between the squares is 100 μm.
-It has a square translucent part (pattern) whose one side is 15 μm, and the interval between the squares is 100 μm.

  After irradiation with light, the coating film was immersed in an aqueous developer containing 0.12% nonionic surfactant and 0.05% potassium hydroxide at 23 ° C. for 80 seconds to develop, washed with water, and 220 in an oven. Post-baking was carried out at 20 ° C. for 20 minutes. The film thickness was measured after standing_to_cool.

  The photosensitive resin composition 1 is evaluated for storage stability. The results are shown in Table 2. Moreover, the cured film was produced like the above using the photosensitive resin composition 1 except not using a photomask, and the item shown in Table 2 was evaluated.

Example 2
In the same manner as the photosensitive resin composition 1, a photosensitive resin composition 2 was obtained and evaluated so as to have the composition shown in Table 1. The results are shown in Table 2.

Example 3
In the same manner as in Example 1, a photosensitive resin composition 3 was obtained and evaluated so as to have the composition shown in Table 1. The results are shown in Table 2.

Comparative Example 1
A photosensitive resin composition 4 was obtained in the same manner as in Example 1 so as to obtain the composition shown in Table 1. When the storage stability was measured in the same manner as in Example 1, the viscosity was increased and the evaluation was stopped.

Comparative Example 2
A photosensitive resin composition 5 was obtained in the same manner as in Example 1 so as to obtain the composition shown in Table 1. When the storage stability was measured in the same manner as in Example 1, the viscosity was increased and the evaluation was stopped.

Description in Table 2 Storage stability: The photosensitive resin composition was stored at 23 ° C. for 2 weeks, and the value obtained by dividing the viscosity of the photosensitive resin composition after storage by the viscosity of the composition 1 before storage in% displayed. The smaller the change in viscosity, the better, for example, in the range of 100 to 103%.
In Comparative Example 1, evaluation was stopped because large thickening was observed.

  Viscosity: Measured at 23 ° C. using a viscometer (VISCOMETER TV-30; manufactured by Toki Sangyo Co., Ltd.).

Transmittance: In the exposure process, except for not using a photomask, the same operation as described above was performed, and the film thickness of the cured film produced to a film thickness of 2.9 to 3.1 μm was measured using a film thickness measuring device. (DEKTAK3; manufactured by Nippon Vacuum Technology Co., Ltd.)
Subsequently, the transmittance | permeability when the transmittance | permeability (%) in 400 nm was measured and extrapolated to the film thickness of 3.0 micrometers was measured for the obtained cured film using a microspectrophotometer (OSP-SP200; made by OLYMPUS). The results are shown in Table 2.

Surface smoothness, line width, shape (cross section): The obtained cured film was observed and measured using a scanning electron microscope (S-4000; manufactured by Hitachi, Ltd.).
Note that the line width was evaluated by ◯ indicating that the pattern could be resolved in each pattern of 10 μm and 15 μm on the photomask, and x indicating that the pattern could not be resolved.

Mechanical properties (total displacement and recovery rate): About the obtained cured film, the total displacement (μm) and the elastic displacement were measured using a dynamic ultra-micro hardness meter (DUH-W201; manufactured by Shimadzu Corporation). (Μm) was measured, and the recovery rate (%) was calculated.
-Measurement conditions-
Test mode; load-unload test test force; 5 gf [SI unit converted value; 49.0 mN]
Load speed: 0.45 gf / sec [SI unit converted value; 4.41 mN / sec]
Holding time: 5 sec
Indenter: truncated cone indenter (diameter 50 μm)
Recovery rate (%); (elastic displacement (μm) / total displacement (μm)) × 100

Solvent resistance: In the exposure step, the same operation was performed except that no photomask was used, a coating film was prepared, and the film thickness and transmittance were measured. The prepared coating film was immersed in N-methylpyrrolidone at 30 ° C. for 30 minutes, the film thickness and transmittance after the immersion were measured, and their changes were determined according to the following formula.
Change in film thickness (%); (film thickness after immersion (μm) / film thickness before immersion (μm)) × 100
Change in transmittance (%); (transmittance after immersion (%) / transmittance before immersion (%)) × 100
When the change in the film thickness and the change in the transmittance were 103% or less, the result was shown as “◯”, and when it exceeded 105%, the result was shown as “X”.
Adhesiveness: On the coating film after immersion in the solvent resistance test, 100 squares each having a side of 1 mm were produced using a commercially available cutter knife. A peel test was performed using a commercially available cellophane tape. [(Number of squares left on the substrate without peeling) / 100] is shown in Table 2. The larger the value, the better the adhesion and the better.

Heat resistance: In the exposure process, the same operation was performed except that no photomask was used, and a coating film was prepared. The prepared coating film was allowed to stand in a clean oven at 240 ° C. for 1 hour, and the film thickness and transmittance (measurement wavelength; 400 nm) before and after heating were measured, and their changes were determined according to the following formula.
Change in film thickness (%); (film thickness after heating (μm) / film thickness before heating (μm)) × 100
Change in transmittance (%); (transmittance after heating (%) / transmittance before heating (%)) × 100
Adhesiveness: 100 squares each having a side of 1 mm were produced on the coated film after heating in the heat resistance test using a commercially available cutter knife. A peel test was performed using a commercially available cellophane tape. [(Number of squares left on the substrate without peeling) / 100] is shown in Table 2. The larger the value, the better the adhesion and the better.

  From the results of Examples 1 to 3 shown in Table 2, the photosensitive resin composition of the present invention containing a binder polymer having an epoxy group having a specific structure is excellent in storage stability, and the photosensitive resin composition of the present invention. It can be seen that a pattern and a coating film excellent in pattern shape, surface smoothness, mechanical properties, heat resistance and solvent resistance can be obtained. On the other hand, only the photosensitive resin composition which does not contain the binder resin of the present invention of Comparative Example 1 was inferior in storage stability.

  The photosensitive resin composition of the present invention is excellent in storage stability, and can form a pattern and a coating film excellent in pattern shape, surface smoothness, mechanical properties, heat resistance, and solvent resistance, It can be used to form a transparent film used in a display device, such as an overcoat, a photo spacer, an insulating film, a protrusion for controlling liquid crystal alignment, and a coat layer for adjusting the thickness of a colored pattern.

Claims (4)

  In the photosensitive resin composition containing the binder resin (A), the photopolymerizable compound (B), the photopolymerization initiator (C) and the solvent (D), the binder resin (A) is an unsaturated carboxylic acid and / or Copolymerizable with unsaturated carboxylic acid anhydride (A1), compound (A2) having a polycyclic aliphatic group having an epoxy group on the ring and a group having an unsaturated bond, and (A1) and (A2) Photosensitive resin composition which is a copolymer with a monomer (excluding (A1) and (A2)) (A3). The compound (A2) having a polycyclic aliphatic group having an epoxy group on the ring and a group having an unsaturated bond comprises a compound represented by the formula (I) and a compound represented by the formula (II). The photosensitive resin composition according to claim 1, which is at least one compound selected from the group.

[In formula (I) and formula (II), R represents a C1-C4 alkyl group which may be each independently substituted with a hydrogen atom or a hydroxyl group.
X represents each independently a C1-C6 alkylene group which may contain a single bond or a hetero atom. ]   The pattern formed using the photosensitive resin composition of Claim 1 or 2. A display device comprising the pattern according to claim 3.