Photosensitive resin composition and color filter

Abstract

The present invention provides a photosensitive resin composition containing a copolymer (A), a reactive diluent (B), a photopolymerization initiator (C), and a solvent (D). The copolymer (A) includes a constituent unit (a-1) represented by formula (1) below, and a constituent unit (a-2) derived from a polymerizable unsaturated compound and having an acid group. The content of the constituent unit (a-1) exceeds 50 mol% of the total constituent units of the copolymer (A). The solvent (D) includes at least one substance selected from primary alcohols having three to ten carbon atoms and secondary alcohols having three to ten carbon atoms.　(In formula (1), R1 represents a hydrogen atom or a methyl group, at least one of R2 to R4 is an alkoxy group having one to six carbon atoms, and at least one of R2 to R4 is a hydrogen atom or an alkyl group having one to six carbon atoms. )

Description

[Technical Field]

[0001] The present invention relates to a photosensitive resin composition, a cured resin film, a color filter, and an image display element. [Background technology]

[0002] In recent years, photosensitive resin compositions for use in components of image display devices such as touch panels, liquid crystal display devices, and organic EL devices, such as color filters, black matrices, overcoats provided on color filters, interlayer insulating films, and protective films, have been actively studied.

[0003] For example, Patent Document 1 discloses a composition for forming a cured film, which contains a polymerizable compound that polymerizes by reaction with a thiol and a radiation-sensitive thiol generator having two or more sulfur-containing groups in one molecule. Patent Document 1 also describes that a cured film can be formed through steps such as applying the composition for forming a cured film to a substrate, exposing it to light, developing it, and post-baking it.

[0004] Furthermore, Patent Document 2 discloses a colored photosensitive resin composition containing (Component A) a copolymer containing at least a structural unit (a1) having a residue in which a carboxyl group and / or a phenolic hydroxyl group is protected with a thermally decomposable group, a structural unit (a2) having an epoxy group and / or an oxetanyl group, and a structural unit (a3) ​​having a carboxyl group and / or a phenolic hydroxyl group. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-184117 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-22048 Summary of the Invention [Problem to be solved by the invention]

[0006] Patent Document 1 describes that the composition for forming a cured film can form a cured film that has high hardness and excellent solvent resistance while improving storage stability and radiation sensitivity. However, the storage stability and hardness are insufficient, and further improvement is desired.

[0007] Furthermore, an alignment film such as a polyimide film is provided on the color filter substrate to align the liquid crystal. In this case, the color filter layer is exposed to highly polar solvents such as N-methylpyrrolidone (NMP) contained in the polyimide resin, so the color filter layer is required to have solvent resistance (NMP resistance). However, the colored photosensitive resin composition of Patent Document 2 has insufficient solvent resistance, and further improvement is desired. Furthermore, when a copolymer containing an epoxy group or an oxetanyl group as described in Patent Document 2 is used, storage stability deteriorates, making it difficult to put into practical use in terms of productivity.

[0008] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a photosensitive resin composition containing a copolymer that has good developability, can form a cured resin film that is excellent in hardness and solvent resistance, and has excellent storage stability. Another object of the present invention is to provide a cured resin film that is excellent in hardness and solvent resistance, a color filter, and an image display element including the same. [Means for solving the problem]

[0009] The present invention includes the following aspects. [1] A photosensitive resin composition comprising (A) a copolymer, (B) a reactive diluent, (C) a photopolymerization initiator, and (D) a solvent, The copolymer (A) contains a structural unit (a-1) represented by the following formula (1) and a structural unit (a-2) derived from a polymerizable unsaturated compound and having an acid group, the content of the structural unit (a-1) in all structural units of the copolymer (A) is greater than 50 mol%, A photosensitive resin composition, wherein the (D) solvent contains at least one selected from primary alcohols having 3 to 10 carbon atoms and secondary alcohols having 3 to 10 carbon atoms.

[0010] [ka]

[0011] (In formula (1), R 1 represents a hydrogen atom or a methyl group, and R 2 ~R 4 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, and n is an integer of 1 to 10. 2 ~R 4 At least one of R is an alkoxy group having 1 to 6 carbon atoms; 2 ~R 4 At least one of them is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.)

[0012] [2] In the structural unit (a-1) represented by the formula (1), R 2 ~R 4 two of which are alkoxy groups having 1 to 2 carbon atoms, and R 2 ~R 4 The photosensitive resin composition according to [1], wherein one of the groups is an alkyl group having 1 to 2 carbon atoms.

[0013] [3] The photosensitive resin composition according to [1] or [2], wherein the acid group of the structural unit (a-2) in the copolymer (A) is a carboxy group, and the acid value of the copolymer (A) is 15 to 300 KOH mg / g.

[0014] [4] The photosensitive resin composition according to any one of [1] to [3], wherein the structural unit (a-2) in the copolymer (A) is a structural unit derived from (meth)acrylic acid.

[0015] [5] The photosensitive resin composition according to any one of [1] to [4], wherein the total content of the primary alcohol having 3 to 10 carbon atoms and the secondary alcohol having 3 to 10 carbon atoms in the solvent (D) is 20 to 100 mass%.

[0016] [6] The photosensitive resin composition according to any one of [1] to [5], wherein the weight average molecular weight of the copolymer (A) is 1,000 to 50,000, and the molecular weight distribution (Mw / Mn) of the copolymer (A) is 1.3 to 3.0.

[0017] [7] The photosensitive resin composition according to any one of [1] to [6], further comprising (E) a colorant.

[0018] [8] The photosensitive resin composition according to any one of [1] to [7], wherein, when the total amount of components excluding the (D) solvent is 100 parts by mass, the content of the (A) copolymer is 5 to 85 parts by mass, the content of the (B) reactive diluent is 5 to 85 parts by mass, and the content of the (C) photopolymerization initiator is 0.1 to 30 parts by mass.

[0019] [9] A cured resin film comprising a cured product of the photosensitive resin composition according to any one of [1] to [8].

[0020]

[10] A color filter having a colored pattern made of a cured product of the photosensitive resin composition according to [7].

[0021]

[11] An image display device comprising the color filter according to

[10] . [Effects of the Invention]

[0022] According to the present invention, there is provided a photosensitive resin composition containing a copolymer that has good developability, can form a cured resin film that is excellent in hardness and solvent resistance, and has excellent storage stability. Furthermore, according to the present invention, there are provided a cured resin film that is excellent in hardness and solvent resistance, a color filter, and an image display element including the same. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a schematic cross-sectional view showing a color filter according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to the embodiments described below. In this specification, "(meth)acrylic acid" means at least one selected from methacrylic acid and acrylic acid, "(meth)acrylate" means at least one selected from methacrylate and acrylate, and "(meth)acryloyl" means at least one selected from methacryloyl and acryloyl.

[0025] <Photosensitive resin composition> The photosensitive resin composition of this embodiment contains (A) a copolymer, (B) a reactive diluent, (C) a photopolymerization initiator, and (D) a solvent. The photosensitive resin composition of this embodiment may further contain (E) a colorant, as needed. The photosensitive resin composition of this embodiment is polymerized and cured by light irradiation to form a cured resin film.

[0026] [(A) Copolymer] The copolymer (A) of this embodiment has a structural unit (a-1) represented by the following formula (1) (hereinafter simply referred to as "structural unit (a-1)") and a structural unit (a-2) (hereinafter simply referred to as "structural unit (a-2)") derived from a polymerizable unsaturated compound and having an acid group. The copolymer (A) may, if necessary, also have a structural unit (a-3) (hereinafter simply referred to as "structural unit (a-3)") derived from another polymerizable unsaturated compound.

[0027] [ka]

[0028] (In formula (1), R 1represents a hydrogen atom or a methyl group, and R 2 ~R 4 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, and n is an integer of 1 to 10. 2 ~R 4 At least one of R is an alkoxy group having 1 to 6 carbon atoms; 2 ~R 4 At least one of them is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.)

[0029] In formula (1), R 1 represents a hydrogen atom or a methyl group, and is preferably a methyl group. In formula (1), R 2 ~R 4 The alkyl group having 1 to 6 carbon atoms represented by the formula (I) is preferably an alkyl group having 1 to 4 carbon atoms, and more preferably an alkyl group having 1 to 2 carbon atoms. 2 ~R 4 The alkoxy group having 1 to 6 carbon atoms represented by the formula (I) is preferably an alkoxy group having 1 to 4 carbon atoms, and more preferably an alkoxy group having 1 or 2 carbon atoms. 2 ~R 4 are each independently preferably an alkyl group having 1 to 6 carbon atoms or an alkoxy group having 1 to 6 carbon atoms, and R 2 ~R 4 two of which are alkoxy groups having 1 to 6 carbon atoms, and R 2 ~R 4 It is more preferable that one of R is an alkyl group having 1 to 6 carbon atoms. 2 ~R 4 two of the groups are alkoxy groups having 1 to 2 carbon atoms, i.e., methoxy groups or ethoxy groups, and R 2 ~R 4 It is most preferable that one of R is an alkyl group having 1 to 2 carbon atoms, i.e., a methyl group or an ethyl group. 2 ~R 4When all of are alkoxy groups having 1 to 6 carbon atoms, the number of crosslinking points increases, which is advantageous in terms of hardness when a cured resin film is formed, but the storage stability of the copolymer (A) is insufficient. If the storage stability of the copolymer (A) is insufficient, the storage stability of the photosensitive resin composition decreases. In formula (1), n ​​is an integer of 1 to 10, preferably 1 to 4, and more preferably 3.

[0030] Specific examples of the structural unit (a-1) represented by formula (1) include: A structural unit derived from 3-(meth)acryloyloxypropylmethyldimethoxysilane (in formula (1), R 1 is a hydrogen atom or a methyl group, and R 2 is a methyl group, and R 3 and R 4 is a methoxy group and n is 3), A structural unit derived from 3-(meth)acryloyloxypropylethyldimethoxysilane (in formula (1), R 1 is a hydrogen atom or a methyl group, and R 2 is an ethyl group, and R 3 and R 4 is a methoxy group and n is 3), A structural unit derived from 3-(meth)acryloyloxypropylmethyldiethoxysilane (in formula (1), R 1 is a hydrogen atom or a methyl group, and R 2 is a methyl group, and R 3 and R 4 is an ethoxy group and n is 3), A structural unit derived from 3-(meth)acryloyloxypropylethyldiethoxysilane (in formula (1), R 1 is a hydrogen atom or a methyl group, and R 2 is an ethyl group, and R 3 and R 4 is an ethoxy group and n is 3) Among these, from the viewpoints of ease of material availability and reactivity during synthesis of the copolymer (A), structural units derived from 3-(meth)acryloyloxypropylmethyldimethoxysilane and structural units derived from 3-(meth)acryloyloxypropylmethyldiethoxysilane are preferred as the structural unit (a-1).

[0031] The content of the structural unit (a-1) in all structural units of the copolymer (A) is more than 50 mol%, preferably from more than 50 mol% to 90 mol%, and more preferably from more than 50 mol% to 80 mol%. If the content of the structural unit (a-1) is 50 mol% or less, the developability as a photosensitive resin composition will be insufficient, and the hardness and solvent resistance of the cured resin film will be insufficient.

[0032] The structural unit (a-2) derived from a polymerizable unsaturated compound and having an acid group contained in the copolymer (A) of this embodiment can be introduced by copolymerizing a polymerizable unsaturated compound having an acid group. The polymerizable unsaturated compound having an acid group is not particularly limited as long as it has an acid group and an ethylenically unsaturated group and does not contain silicon. The acid group contained in the structural unit (a-2) is not particularly limited, but typically, a carboxy group, a phosphate group (-OP(=O)(OH)), a sulfonic acid group (-S(=O)OH), etc. are preferred. Among these, a carboxy group is more preferred from the viewpoint of developability as a photosensitive resin composition.

[0033] Specific examples of the structural unit (a-2) include structural units derived from (meth)acrylic acid, crotonic acid, cinnamic acid, vinyl sulfonic acid, 2-(meth)acryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, 2-(meth)acryloyloxyethyl acid phosphate, etc. Among these, from the viewpoints of ease of availability and reactivity during synthesis of the copolymer (A), a structural unit derived from (meth)acrylic acid is preferred as the structural unit (a-2).

[0034] The content of the structural unit (a-2) in all structural units of the copolymer (A) is preferably 5 mol% or more but less than 50 mol%, more preferably 10 mol% to 45 mol%, and most preferably 20 mol% to 40 mol%. When the content of the structural unit (a-2) is 5 mol% or more, good developability is obtained when the photosensitive resin composition is applied to a substrate, exposed to light, and developed. When the content of the structural unit (a-2) is less than 50 mol%, the content of the structural unit (a-1) becomes sufficiently high, and good hardness is obtained as a cured resin film.

[0035] In addition to the structural units (a-1) and (a-2), the copolymer (A) of this embodiment may also contain a structural unit (a-3) derived from another polymerizable unsaturated compound. The other polymerizable unsaturated compound is a polymerizable unsaturated compound that does not have an acid group or a silyl group. Examples of the other polymerizable unsaturated compound include dienes such as butadiene, (meth)acrylic acid esters, (meth)acrylic acid amides, styrenes, unsaturated dicarboxylic acid diesters, unsaturated polybasic acid anhydrides, and other vinyl compounds.

[0036] Specific examples of (meth)acrylic acid esters include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, sec-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, neopentyl (meth)acrylate, benzyl (meth)acrylate, isoamyl (meth)acrylate, and hexyl (Meth)acrylate, 2-ethylhexyl (meth)acrylate, benzyl (meth)acrylate, lauryl (meth)acrylate, dodecyl (meth)acrylate, cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, ethylcyclohexyl (meth)acrylate, 1,4-cyclohexanedimethanol mono(meth)acrylate, rosin (meth)acrylate, norbornyl (meth)acrylate, 5-methylnorbornyl N,N-dimethylaminopropyl (meth)acrylate, 3-(N,N-dimethylamino)propyl (meth)acrylate, 1,1,1-trifluoroethyl (meth)acrylate, perfluoroethyl (meth)acrylate, perfluoro-n-propyl (meth)acrylate, perfluoro-isopropyl (meth)acrylate, triphenylmethyl (meth)acrylate, cumyl (meth)acrylate, 3-(N,N-dimethylamino)propyl (meth)acrylate Acrylates, glyceryl mono(meth)acrylate, butanetriol mono(meth)acrylate, pentanetriol mono(meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentanyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, naphthalene (meth)acrylate, anthracene (meth)acrylate, 2-(2-vinyloxyethoxy)ethyl (meth)acrylate, glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, 2-isocyanatoethyl (meth)acrylate, 2-isocyanatopropyl (meth)acrylate, 3-isocyanatopropyl (meth)acrylate, 2-isocyanato-1-methylethyl (meth)acrylate, 2-isocyanato-1,1-dimethylethyl (meth)acrylate, 4-isocyanatocyclohexyl (meth)acrylate, and compounds having a blocked isocyanato group obtained by blocking the isocyanato group of the above-mentioned ethylenically unsaturated compounds having an isocyanato group with a blocking agent; ... Hydroxy group-containing (meth)acrylates such as hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 2-hydroxy-3-phenoxypropyl (meth)acrylate; N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N-tert-butylaminoethyl (meth)acrylate, tetramethylpiperidyl (meth)acrylate, and hexamethylpiperidyl (meth)acrylate.

[0037] Specific examples of (meth)acrylic acid amides include (meth)acrylic acid amide, (meth)acrylic acid N,N-dimethylamide, (meth)acrylic acid N,N-diethylamide, (meth)acrylic acid N,N-dipropylamide, (meth)acrylic acid N,N-di-isopropylamide, (meth)acrylic acid anthracenylamide, N-isopropyl(meth)acrylamide, (meth)acrylic morpholine, and diacetone(meth)acrylamide.

[0038] Specific examples of styrenes include styrene, α-, o-, m-, p-alkyl, nitro, cyano and amide derivatives of styrene.

[0039] Specific examples of the unsaturated dicarboxylic acid diester include diethyl citraconate, diethyl maleate, diethyl fumarate, and diethyl itaconate.

[0040] Specific examples of the unsaturated polybasic acid anhydride include maleic anhydride, itaconic anhydride, and citraconic anhydride.

[0041] Specific examples of other vinyl compounds include norbornene (bicyclo[2.2.1]hept-2-ene), 5-methylbicyclo[2.2.1]hept-2-ene, 5-ethylbicyclo[2.2.1]hept-2-ene, tetracyclo[4.4.0.12,5.17,10]dodec-3-ene, 8-methyltetracyclo[4.4.0.12,5.17,10]dodec-3-ene, 8-ethyltetracyclo[4.4.0.12,5.17,10]dodec-3-ene, chloro[4.4.0.12,5.17,10]dodec-3-ene, dicyclopentadiene, tricyclo[5.2.1.02,6]dec-8-ene, tricyclo[5.2.1.02,6]dec-3-ene, tricyclo[4.4.0.12,5]undec-3-ene, tricyclo[6.2.1.01,8]undec-9-ene, tricyclo[6.2.1.01,8]undec-4-ene, tetracyclo[4 .4.0.12,5.17,10.01,6]dodec-3-ene, 8-methyltetracyclo[4.4.0.12,5.17,10.01,6]dodec-3-ene, 8-ethylidenetetracyclo[4.4.0.12,5.17,12]dodec-3-ene, 8-ethylidenetetracyclo[4.4.0.12,5.17,10.01,6]dodec-3-ene, pentacyclo[6.5.1.13,6.02 ,7.09,13]pentadec-4-ene, pentacyclo[7.4.0.12,5.19,12.08,13]pentadec-3-ene, 5-norbornene-2,3-dicarboxylic anhydride, (meth)acrylic acid anilide, (meth)acryloylnitrile, acrolein, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylpyridine, vinyl acetate, vinyltoluene, etc.

[0042] These polymerizable unsaturated compounds may be used alone or in combination of two or more.

[0043] Among these, from the viewpoints of availability and reactivity, the other polymerizable unsaturated compounds are preferably methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, benzyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, dicyclopentanyl (meth)acrylate, glycidyl (meth)acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, (meth)acrylic acid N,N-dimethylamide, (meth)acrylic morpholine, styrene, vinyltoluene, and norbornene, and more preferably methyl (meth)acrylate, benzyl (meth)acrylate, dicyclopentanyl (meth)acrylate, glycidyl (meth)acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, a (meth)acrylic acid ester having a blocked isocyanato group, styrene, and vinyltoluene.

[0044] Examples of the blocking agent include lactams such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, and β-propiolactam; alcohols such as methanol, ethanol, propanol, butanol, ethylene glycol, methyl cellosolve, butyl cellosolve, methyl carbitol, benzyl alcohol, phenyl cellosolve, furfuryl alcohol, and cyclohexanol; phenols such as phenol, cresol, xylenol, ethylphenol, o-isopropylphenol, and butylphenols such as p-tert-butylphenol, p-tert-octylphenol, nonylphenol, dinonylphenol, styrenated phenol, oxybenzoic acid esters, thymol, p-naphthol, p-nitrophenol, and p-chlorophenol; and dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, and acetyl Examples of such amines include active methylene-based amines such as acetone; mercaptan-based amines such as diphenylamine, phenylnaphthylamine, aniline, and carbazole; acid amide-based amines such as acetanilide, acetanisidide, acetic acid amide, and benzamide; acid imide-based amines such as succinimide and maleimide; imidazole-based amines such as imidazole, 2-methylimidazole, and 2-ethylimidazole; urea-based amines such as urea, thiourea, and ethyleneurea; carbamate-based amines such as N-phenylphenylcarbamate and 2-oxazolidone; imine-based amines such as ethyleneimine and polyethyleneimine; oxime-based amines such as formaldoxime, acetaldoxime, acetoxime, methyl ethyl ketoxime, methyl isobutyl ketoxime, and cyclohexanone oxime; and bisulfite-based amines such as sodium bisulfite and potassium bisulfite.

[0045] When the copolymer (A) of this embodiment contains the structural unit (a-3), the content of the structural unit (a-3) in all structural units of the copolymer (A) is preferably 0.1 mol % to 40 mol %, more preferably 1 mol % to 30 mol %, and most preferably 5 mol % to 20 mol %. When the content of the structural unit (a-3) is 0.1 mol % or more, the photosensitive resin composition can be sufficiently imparted with the functionality attributable to the structural unit (a-3). When the content of the structural unit (a-3) is 40 mol % or less, the contents of the structural unit (a-1) and the structural unit (a-2) are sufficiently high, so that the photosensitive resin composition has good developability and a cured resin film with excellent hardness and adhesion can be obtained.

[0046] The weight-average molecular weight (Mw) of the (A) copolymer of this embodiment, in terms of polystyrene, is preferably 1,000 to 50,000, more preferably 2,000 to 30,000, and most preferably 3,000 to 10,000. When the weight-average molecular weight (Mw) of the (A) copolymer is 1,000 or more, defects such as chipping in the cured resin film after development are less likely to occur. When the weight-average molecular weight of the (A) copolymer is 50,000 or less, the development time as a photosensitive resin composition is sufficiently short, and the composition is highly practical.

[0047] The weight average molecular weight (Mw) of the copolymer (A) of this embodiment is measured using gel permeation chromatography (GPC) under the following conditions and calculated in terms of polystyrene. Column: Showdex (registered trademark) LF-804 + LF-804 (manufactured by Showa Denko K.K.) Column temperature: 40℃ Sample: (A) Tetrahydrofuran solution containing 0.2% by mass of copolymer Developing solvent: tetrahydrofuran Detector: Differential refractometer (product name: Showdex (registered trademark) RI-71S, manufactured by Showa Denko K.K.) Flow rate: 1mL / min

[0048] The molecular weight distribution (Mw / Mn) of the copolymer (A) of this embodiment is preferably 1.3 to 3.0, more preferably 1.5 to 2.8, and most preferably 1.5 to 2.6. When the molecular weight distribution (Mw / Mn) of the copolymer (A) is 1.3 or more, it is possible to optimize the target numerical ranges of the weight average molecular weight, acid value, etc., and to set reaction conditions, etc., within a certain range when producing the copolymer (A), which is efficient. When the molecular weight distribution (Mw / Mn) of the copolymer (A) is 3.0 or less, there is no variation in the performance of the photosensitive resin composition, such as developability. The molecular weight distribution is measured from the chromatogram of the GPC measurement described above. Note that Mn represents the number average molecular weight.

[0049] The acid value of the copolymer (A) of this embodiment is not particularly limited, but is preferably 15 KOHmg / g to 300 KOHmg / g, more preferably 20 KOHmg / g to 200 KOHmg / g, and most preferably 25 KOHmg / g to 150 KOHmg / g. When the acid value of the copolymer (A) is 15 KOHmg / g or more, better developability can be obtained. When the acid value of the copolymer (A) is 300 KOHmg / g or less, the exposed portion (photocured portion) does not dissolve in an alkaline developer, and good developability can be obtained. The acid value of the (A) copolymer is a value measured using a mixed indicator of bromothymol blue and phenol red in accordance with JIS K6901 5.3, and means the number of milligrams of potassium hydroxide required to neutralize the acidic components contained in 1 g of the (A) copolymer.

[0050] The silyl group equivalent of the copolymer (A) of this embodiment is not particularly limited, but is preferably 250 g / mol to 4000 g / mol, more preferably 300 g / mol to 2000 g / mol, and most preferably 300 g / mol to 1000 g / mol. When the silyl group equivalent of the copolymer (A) is 250 g / mol or more, it is effective in further improving hardness and developability. When the silyl group equivalent of the copolymer (A) is 4000 g / mol or less, sufficient hardness can be ensured as a cured resin film. The silyl group equivalent of the (A) copolymer is the molecular weight of the (A) copolymer divided by the average number of silyl groups per molecule, and is a calculated value calculated based on the amount of the polymerizable unsaturated compound used as the raw material for the structural unit (a-1) when synthesizing the (A) copolymer. Even if different types of silyl groups are contained, the silyl group is simply counted as a silyl group.

[0051] The content of the copolymer (A) in the photosensitive resin composition of this embodiment is preferably 5 to 85 parts by mass, more preferably 15 to 75 parts by mass, and most preferably 20 to 65 parts by mass, when the total of all components excluding the solvent (D) is 100 parts by mass. When the content of the copolymer (A) is within the above range, the photocurability of the photosensitive resin composition becomes more appropriate.

[0052] The copolymer (A) of this embodiment can be prepared by copolymerizing a monomer mixture consisting of (A-1) a compound represented by the following formula (2) (hereinafter also simply referred to as "compound (A-1)"), (A-2) a polymerizable unsaturated compound having an acid group (hereinafter also simply referred to as "compound (A-2)"), and (A-3) other polymerizable unsaturated compounds used as needed (hereinafter also simply referred to as "compound (A-3)") in the presence of a solvent (D-1) according to a radical polymerization method known in the technical field.

[0053] [ka]

[0054] (R in Equation (2) 1 ~R 4 and n is R in formula (1). 1 ~R 4 and n.)

[0055] Specifically, the (A-1) compound, the (A-2) compound, and the optional (A-3) compound are dissolved in the (D-1) solvent to prepare a solution, and then a polymerization initiator is added to the solution and the reaction is carried out at 50°C to 130°C for 1 to 20 hours. The number of repeating units derived from each compound in the (A) copolymer and the order in which the structural units derived from each compound are bonded are not particularly limited. Alternatively, a copolymer containing the structural units (a-1), (a-2), and (a-3) may be prepared by first introducing the missing structural units into the copolymer through a modification reaction.

[0056] As the compounds (A-1) to (A-3), the compounds listed above as raw materials for the structural units (a-1) to (a-3) can be used.

[0057] For the same reasons as for specifying the content ratios of the structural units (a-1) to (a-3) constituting the copolymer (A), the amounts of the (A-1) compound, the (A-2) compound, and the (A-3) compound can be specified. That is, when the total of the (A-1) and (A-2) compounds is taken as 100 mol%, the amount of the (A-1) compound is more than 50 mol%, preferably more than 50 mol% to 90 mol%, and most preferably more than 50 mol% to 80 mol%. The amount of the (A-2) compound is preferably 5 mol% or more but less than 50 mol%, more preferably 10 mol% to 45 mol%, and most preferably 20 mol% to 40 mol%, when the total of the (A-1) and (A-2) compounds is taken as 100 mol%. When the (A-3) compound is used, the blending amount is preferably 0.1 mol % to 40 mol %, more preferably 1 mol % to 30 mol %, and most preferably 5 mol % to 20 mol %, when the total of the (A-1) to (A-3) compounds is 100 mol %.

[0058] The solvent (D-1) used in preparing the copolymer (A) is not particularly limited as long as it is inert to the polymerization reaction. It is preferable to use the same solvent as the solvent (D) used in the photosensitive resin composition (described later), since this eliminates the need to separate and remove the polymerization solvent. Furthermore, from the viewpoint of controlling the weight-average molecular weight (Mw) and molecular weight distribution (Mw / Mn) of the copolymer (A) within a predetermined range and obtaining a photosensitive resin composition with desired storage stability, it is preferable to use the solvent (D-1) containing at least one selected from primary alcohols having 3 to 10 carbon atoms and secondary alcohols having 3 to 10 carbon atoms.

[0059] When the (D-1) solvent contains at least one selected from a primary alcohol having 3 to 10 carbon atoms and a secondary alcohol having 3 to 10 carbon atoms, the total content of the primary alcohol having 3 to 10 carbon atoms and the secondary alcohol having 3 to 10 carbon atoms is preferably 20% to 100% by mass, and more preferably 50% to 100% by mass, relative to the (D-1) solvent. When the total content of the primary alcohol having 3 to 10 carbon atoms and the secondary alcohol having 3 to 10 carbon atoms is within the above range, it is easy to control the weight-average molecular weight (Mw) and molecular weight distribution (Mw / Mn) of the (A) copolymer within predetermined ranges, and when the (D-1) solvent is used as the (D) solvent for the photosensitive resin composition as is, the storage stability of the photosensitive resin composition can be further improved.

[0060] The amount of the (D-1) solvent used in preparing the (A) copolymer is not particularly limited, but is preferably 30 to 1,000 parts by mass, and more preferably 50 to 800 parts by mass, based on 100 parts by mass of the total amount of the (A-1) compound, the (A-2) compound, and the (A-3) compound used as needed. When the amount used is 30 parts by mass or more, the polymerization reaction can be carried out stably, and coloration and gelation of the (A) copolymer can be prevented. When the amount used is 1,000 parts by mass or less, a decrease in the molecular weight of the (A) copolymer due to chain transfer can be suppressed, and the viscosity of the reaction solution can be controlled within an appropriate range.

[0061] The polymerization initiator that can be used in this copolymerization reaction is not particularly limited, but examples thereof include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(isobutyrate) dimethyl, benzoyl peroxide, t-butylperoxy-2-ethylhexanoate, etc. These polymerization initiators may be used alone or in combination of two or more. The amount of the polymerization initiator used is not particularly limited, but is preferably 0.1 to 20 parts by mass, and more preferably 0.5 to 16 parts by mass, when the total amount of the (A-1) compound, the (A-2) compound, and the (A-3) compound used as needed is taken as 100 parts by mass.

[0062] [(B) Reactive diluent] The reactive diluent (B) of this embodiment is not particularly limited as long as it is a low-molecular-weight compound having an ethylenically unsaturated group such as a vinyl group, an allyl group, a (meth)acryloyloxy group, etc. Specific examples of the reactive diluent (B) include aromatic vinyl monomers, polycarboxylic acid monomers such as vinyl acetate and vinyl adipate, (meth)acrylates, polyfunctional (meth)acrylates, triallyl cyanurate, etc.

[0063] Specific examples of aromatic vinyl monomers include styrene, α-methylstyrene, α-chloromethylstyrene, vinyltoluene, divinylbenzene, diallyl phthalate, and diallyl benzene phosphonate.

[0064] Specific examples of (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, β-hydroxyethyl (meth)acrylate, and hydroxypropyl (meth)acrylate.

[0065] Specific examples of polyfunctional (meth)acrylates include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and tris(hydroxyethyl)isocyanurate tri(meth)acrylate.

[0066] As the (B) reactive diluent, polyfunctional (meth)acrylates are particularly preferred.

[0067] These (B) reactive diluents may be used alone or in combination of two or more.

[0068] The content of the (B) reactive diluent in the photosensitive resin composition of this embodiment is preferably 5 to 85 parts by mass, more preferably 15 to 75 parts by mass, and most preferably 20 to 65 parts by mass, when the total of all components excluding the (D) solvent is 100 parts by mass. When the content of the (B) reactive diluent is within the above range, the viscosity and photocurability of the photosensitive resin composition become more appropriate.

[0069] [(C) Photopolymerization initiator] The photopolymerization initiator (C) of this embodiment is not particularly limited as long as it is a compound that generates radicals upon irradiation with light. Examples of the photopolymerization initiator (C) include benzoin and its alkyl ethers such as benzoin, benzoin methyl ether, and benzoin ethyl ether; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, and 4-(1-t-butyldioxy-1-methylethyl)acetophenone; alkylphenones such as 1-hydroxycyclohexyl phenyl ketone and 2-hydroxy-2-methyl-1-phenylpropan-1-one; anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone, and 1-chloroanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorothioxanthone; acetophenone dimethyl ketal, acetophenone dimethyl ketal, and acetophenone dimethyl ketal. ketals such as benzyl dimethyl ketal; benzophenone, 4-(1-t-butyldioxy-1-methylethyl)benzophenone, 3,3',4,4'-tetrakis(t-butyldioxycarbonyl)benzophenone; 1,2-octanedione, 1-[4-(phenylthio)-2-(o-benzoyloxime)], ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl], 1 ... oxime esters such as 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one; 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone-1; acylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide; xanthones, etc. These (C) photopolymerization initiators may be used alone or in combination of two or more.

[0070] The content of the (C) photopolymerization initiator in the photosensitive resin composition of this embodiment is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 20 parts by mass, and most preferably 1 to 15 parts by mass, when the total of all components excluding the (D) solvent is 100 parts by mass. When the content of the (C) photopolymerization initiator is 0.1 part by mass or more, the photosensitive resin composition has sufficient photocurability. When the content of the (C) photopolymerization initiator is 30 parts by mass or less, there is no adverse effect on the storage stability of the photosensitive resin composition or the performance of the cured resin film.

[0071] [(D) Solvent] The (D) solvent of this embodiment is not particularly limited as long as it contains at least one selected from a primary alcohol having 3 to 10 carbon atoms and a secondary alcohol having 3 to 10 carbon atoms, and is inert to and capable of dissolving each component of the photosensitive resin composition. The (D-1) solvent used in preparing the (A) copolymer may be the same as the (D) solvent, and this solvent may be used as the (D) solvent for the photosensitive resin composition without being separated or removed. Alternatively, a new solvent may be added when mixing the components of the photosensitive resin composition. The (D) solvent may also be a solvent that coexists with the components of the photosensitive resin composition when they are mixed. From the viewpoint of storage stability of the photosensitive resin composition, the (D) solvent preferably contains a primary alcohol having 3 to 10 carbon atoms. Examples of the primary alcohol solvent having 3 to 10 carbon atoms and the secondary alcohol solvent having 3 to 10 carbon atoms include monoalcohols and (poly)alkylene glycol monoalkyl ethers.

[0072] Specific examples of monoalcohols include primary alcohols such as propyl alcohol, butyl alcohol, pentyl alcohol, hexyl alcohol, octyl alcohol, nonyl alcohol, decyl alcohol, and dodecyl alcohol; and secondary alcohols such as benzyl alcohol.

[0073] Specific examples of the (poly)alkylene glycol monoalkyl ethers include ethylene glycol monomethyl ether, ethylene glycol monoethyl 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, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, and primary alcohols such as 3-methoxy-1-butanol.

[0074] Among these, (poly)alkylene glycol monoalkyl ethers are preferred as the (D) solvent from the viewpoints of availability and storage stability as a photosensitive resin composition.

[0075] These (D) solvents may be used alone or in combination of two or more.

[0076] The solvent (D) of this embodiment may contain other solvents in addition to the above-mentioned solvents. Specific examples of other solvents include tertiary alcohols such as tert-butyl alcohol and diacetone alcohol; (poly)alkylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, and propylene glycol monoethyl ether acetate; other ethers such as diethylene glycol dimethyl 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, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, and 3-methoxypropionate. esters such as methyl phosphate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutyrate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutylpropionate, ethyl acetate, n-butyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, n-amyl acetate, i-amyl acetate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, i-propyl butyrate, n-butyl butyrate, methyl pyruvate, ethyl pyruvate, n-propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, and ethyl 2-oxobutyrate; aromatic hydrocarbons such as toluene and xylene; and carboxylic acid amides such as N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. Among these, from the viewpoints of compatibility with the primary alcohol having 3 to 10 carbon atoms or the secondary alcohol having 3 to 10 carbon atoms and the solubility of each component of the photosensitive resin composition, (poly)alkylene glycol monoalkyl ether acetate solvents such as propylene glycol monomethyl ether acetate are preferred as other solvents.

[0077] In the (D) solvent, the total content of the primary alcohol having 3 to 10 carbon atoms and the secondary alcohol having 3 to 10 carbon atoms is preferably 20% by mass to 100% by mass, and more preferably 50% by mass to 100% by mass. When the total content of the primary alcohol having 3 to 10 carbon atoms and the secondary alcohol having 3 to 10 carbon atoms is within the above range, the storage stability of the photosensitive resin composition can be further improved. The content of other solvents is preferably 0% by mass to 80% by mass, and more preferably 0% by mass to 50% by mass.

[0078] The content of the (D) solvent in the photosensitive resin composition of this embodiment is preferably 30 to 1,000 parts by mass, more preferably 50 to 800 parts by mass, and most preferably 100 to 700 parts by mass, when the total of all components excluding the (D) solvent is taken as 100 parts by mass. When the (D) solvent content is within the above range, the viscosity of the photosensitive resin composition can be adjusted to an appropriate range.

[0079] [(E) Colorant] The photosensitive resin composition of this embodiment may further contain a (E) colorant, if necessary. A known dye or pigment can be used as the (E) colorant. When a dye is used as the (E) colorant, a colored pattern with higher brightness can be obtained compared to when a pigment is used, and the composition also exhibits good alkali developability.

[0080] As the dye, it is preferable to use an acid dye having an acidic group such as a carboxyl group, a salt of an acid dye with a nitrogen compound, a sulfonamide of an acid dye, etc., from the viewpoints of solubility in (D) solvents and alkaline developers, interaction with other components in the photosensitive resin composition, heat resistance, etc. Examples of such dyes include acid alizarin violet N; acid black 1, 2, 24, 48; acid blue 1, 7, 9, 25, 29, 40, 45, 62, 70, 74, 80, 83, 90, 92, 112, 113, 120, 129, 147; acid chrome violet K; acid Fuchsin; acid green 1, 3, 5, 25, 27, 50; acid orange 6, 7, 8, 10, 12, 50, 51, 52, 56, 63, 74, 95; acid red1, 4, 8, 14, 17, 18, 26, 27, 29, 31, 34, 35, 37, 42, 44, 50, 51, 52, 57, 69, 73, 80, 87, 88, 91, 92, 94, 97, 103, 111, 11 4,129,133,134,138,143,145,150,151,158,176,183,198,211,215,216,217,249,252,257,260,266,274;acid violet 6B, 7, 9, 17, 19;acid Examples of suitable dyes include Food Yellow 1, 3, 9, 11, 17, 23, 25, 29, 34, 36, 42, 54, 72, 73, 76, 79, 98, 99, 111, 112, 114, and 116; Food Yellow 3, and derivatives thereof. Among these, azo-based, xanthene-based, anthraquinone-based, and phthalocyanine-based acid dyes are preferred. These dyes may be used alone or in combination of two or more, depending on the desired pixel color.

[0081] Examples of pigments include yellow pigments such as CI Pigment Yellow 1, 3, 12, 13, 14, 15, 16, 17, 20, 24, 31, 53, 83, 86, 93, 94, 109, 110, 117, 125, 128, 137, 138, 139, 147, 148, 150, 153, 154, 166, 173, 194, and 214; orange pigments such as CI Pigment Orange 13, 31, 36, 38, 40, 42, 43, 51, 55, 59, 61, 64, 65, 71, and 73; and CI Pigment Red 9, 97, 105, 122, 123, 144, 149, 16 Examples of suitable pigments include red pigments such as CI Pigment Blue 15, 15:3, 15:4, 15:6, and 60; blue pigments such as CI Pigment Violet 1, 19, 23, 29, 32, 36, and 38; green pigments such as CI Pigment Green 7, 36, and 58; brown pigments such as CI Pigment Brown 23 and 25; and black pigments such as CI Pigment Black 1, 7, carbon black, titanium black, and iron oxide. Depending on the color of the desired pixel, one of these pigments may be used alone, or two or more may be used in combination, or a dye and a pigment may be used in combination.

[0082] The content of the (E) colorant in the photosensitive resin composition of the present embodiment is preferably 5 to 75 parts by mass, more preferably 5 to 65 parts by mass, and most preferably 10 to 55 parts by mass, relative to 100 parts by mass of the total of all components excluding the (D) solvent.

[0083] When a pigment is used as the (E) colorant, a known dispersant may be blended into the photosensitive resin composition to improve the dispersibility of the pigment. It is preferable to use a polymer dispersant that has excellent dispersion stability over time. Examples of polymer dispersants include urethane-based dispersants, polyethyleneimine-based dispersants, polyoxyethylene alkyl ether-based dispersants, polyoxyethylene glycol diester-based dispersants, sorbitan aliphatic ester-based dispersants, and aliphatic modified ester-based dispersants. Commercially available polymer dispersants such as EFKA (manufactured by EFKA Chemicals BV), Disperbyk (manufactured by BYK-Chemie), Disparlon (manufactured by Kusumoto Chemicals Co., Ltd.), and SOLSPERSE (manufactured by Zeneca) may also be used. The amount of the dispersant blended in the photosensitive resin composition of the present invention is adjusted appropriately depending on the type of pigment, etc.

[0084] In addition to the above components, the photosensitive resin composition of the present embodiment may contain known additives such as known leveling agents and thermal polymerization inhibitors in order to impart predetermined properties. The amounts of these additives contained in the photosensitive resin composition are not particularly limited as long as they do not impair the effects of the present invention.

[0085] The viscosity of the photosensitive resin composition of this embodiment can be adjusted appropriately depending on the desired thickness of the cured resin film. For example, when the thickness of the cured resin film is adjusted to 1 to 4 μm, the viscosity of the photosensitive resin composition is preferably 1 mP·s to 25 mP·s, more preferably 2 mP·s to 20 mP·s, and most preferably 3 mP·s to 15 mP·s.

[0086] <Method for producing photosensitive resin composition> The photosensitive resin composition of this embodiment may be prepared by mixing the above components using a known mixing device. Alternatively, it may be prepared by first preparing a composition containing the (A) copolymer and the (D) solvent, i.e., copolymerizing a monomer mixture consisting of the (A-1) compound, the (A-2) compound, and the optional (A-3) compound in the presence of the (D) solvent, followed by adding and mixing the (B) reactive diluent, the (C) photopolymerization initiator, and the optional (E) colorant. In the latter preparation method, if necessary, additional solvent (D-2) may be added after copolymerization. The additional solvent (D-2) may be the same as or different from the (D) solvent.

[0087] The photosensitive resin composition of this embodiment has alkali developability, and therefore can be developed using an alkaline aqueous solution. In particular, the photosensitive resin composition of this embodiment can provide a pattern with excellent developability. Therefore, the photosensitive resin composition of this embodiment is suitable for use as a resist used in producing color filters, black matrices, overcoats, protective films, and insulating films incorporated in organic electroluminescence (EL) display devices, liquid crystal display devices, and solid-state imaging devices.

[0088] <Cured resin film> The cured resin film of this embodiment is formed by applying the above-mentioned photosensitive resin composition to a substrate, pre-baking, exposing, and post-baking. When forming a pattern by photolithography, the above-mentioned photosensitive resin composition is applied to a substrate, pre-baked, and then the formed coating film is exposed through a photomask with a predetermined pattern to photo-cure the exposed portions. Then, if necessary, a post-exposure heat treatment is performed, and the unexposed portions are dissolved and developed in an alkaline aqueous solution, followed by post-baking, thereby forming a predetermined pattern.

[0089] [Coating process] The method for applying the photosensitive resin composition is not particularly limited, but may be screen printing, roll coating, curtain coating, spray coating, spin coating, slit coating, or the like.

[0090] [Pre-bake process] After forming a coating film in the coating step, the coating film is preferably prebaked (preheated) to dry it and reduce the amount of solvent remaining in the coating film. The prebaking step can be carried out at a temperature of generally 70 to 120°C, preferably 90 to 110°C, for 10 to 600 seconds, preferably 120 to 180 seconds, when using a hot plate.

[0091] [Exposure process] The surface of the formed coating film is exposed by light irradiation. When a pattern is to be formed, the surface of the coating film is exposed through a photomask having a predetermined pattern. The light source used for light irradiation is not particularly limited, but examples thereof include a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, a xenon lamp, and a metal halide lamp. The exposure dose is also not particularly limited, and is set appropriately depending on the composition of the photosensitive resin composition.

[0092] [Post-exposure baking process] When forming a pattern, post-exposure baking can be performed as needed after the exposure step. This step can more clearly demonstrate the dissolution contrast between the exposed and unexposed areas of the coating film. Unlike the post-bake step described below, this step is not performed to completely harden the coating film, but rather to leave only the pattern of the exposed areas on the substrate after the development step and ensure that the unexposed areas of the coating film can be removed by development. Therefore, this step is not an essential step for forming the cured resin film of this embodiment. When performing post-exposure baking, a hot plate, oven, furnace, or the like can be used. The heating temperature range is preferably 40°C to 70°C, more preferably 50°C to 60°C. A heating temperature of 40°C or higher improves the dissolution contrast between the exposed and unexposed areas of the coating film, allowing the effects of the post-exposure baking to be fully demonstrated. A heating temperature of 70°C or lower prevents the acid generated in the exposed areas from diffusing to the unexposed areas, resulting in good dissolution contrast. The heating time range is preferably 20 seconds to 600 seconds. A heating time of 20 seconds or longer can ensure a uniform temperature history throughout the coating film. If the time is 600 seconds or less, the acid generated in the exposed area does not diffuse to the unexposed area, and a good dissolution contrast can be obtained.

[0093] [Development process] After exposure, if necessary, a post-exposure heat treatment is performed, and then the coating film is developed. The developer used during development can be any developer conventionally used for developing photosensitive resin compositions. The alkaline aqueous solution used for development is not particularly limited, but examples include aqueous solutions of sodium carbonate, potassium carbonate, calcium carbonate, sodium hydroxide, potassium hydroxide, etc.; aqueous solutions of amine compounds such as ethylamine, diethylamine, and dimethylethanolamine; aqueous solutions of quaternary ammonium salts such as tetramethylammonium hydroxide; and aqueous solutions of p-phenylenediamine compounds such as 3-methyl-4-amino-N,N-diethylaniline, 3-methyl-4-amino-N-ethyl-N-β-hydroxyethylaniline, 3-methyl-4-amino-N-ethyl-N-β-methanesulfonamidoethylaniline, and 3-methyl-4-amino-N-ethyl-N-β-methoxyethylaniline, as well as sulfates, hydrochlorides, or p-toluenesulfonates thereof. Among these, aqueous solutions of p-phenylenediamine compounds are preferred. If necessary, an antifoaming agent or a surfactant may be added to these alkaline aqueous solutions. After development with the alkaline aqueous solution, it is preferable to wash with water and then dry.

[0094] [Post-bake process] After the development step, post-baking is performed to obtain a cured resin film. The post-baking conditions are not particularly limited, and the heat treatment may be performed depending on the composition of the photosensitive resin composition. For example, heating at a temperature of 80°C to 250°C for 10 to 60 minutes may be performed. When various resin films are used as the substrate, the temperature range for the post-baking step is preferably 80°C to 130°C, more preferably 80°C to 100°C, from the viewpoint of reducing thermal damage to the substrate and circuits.

[0095] The cured resin film of this embodiment has high light transmittance and excellent transparency. Furthermore, because the cured resin film has good hardness, it can be suitably used as an overcoat on the top of a color filter, various protective films, etc. It can also be suitably used as various insulating materials, such as an insulating film between electrodes, such as ITO, in a touch panel, or an interlayer insulating film in a TFT.

[0096] <Color filter> The color filter of this embodiment is produced using a photosensitive resin composition containing the components (A) to (E) by the above-described method for producing a cured resin film. The color filter of this embodiment will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing the color filter of this embodiment. As shown in FIG. 1, the color filter of this embodiment includes a substrate 1, RGB pixels 2 formed on one surface of the substrate 1, a black matrix 3 formed at the boundaries between the pixels 2, and a protective film 4 formed on the pixels 2 and the black matrix 3.

[0097] The color filter of this embodiment can employ known structures for the other components, except that the pixels 2 and the black matrix 3 (colored pattern) are formed using the above-mentioned photosensitive resin composition. The color filter configuration shown in FIG. 1 is an example, and the color filter of this embodiment is not limited to this configuration.

[0098] Next, a method for manufacturing the color filter of this embodiment will be described. First, a colored pattern is formed on one surface of the substrate 1. Specifically, pixels 2 and a black matrix 3 are formed in this order on one surface of the substrate 1. The colored pattern can be formed by the above-mentioned method for producing a cured resin film (photolithography method). The substrate 1 is not particularly limited, but examples thereof include a glass substrate, a silicon substrate, a polycarbonate substrate, a polyester substrate, a polyamide substrate, a polyamideimide substrate, a polyimide substrate, an aluminum substrate, a printed wiring board, and an array substrate.

[0099] Next, a protective film 4 is formed on the colored pattern (pixels 2 and black matrix 3). The protective film 4 is not particularly limited, and may be formed using a known material and method.

[0100] The color filter thus produced is produced using a photosensitive resin composition that has good storage stability and excellent developability, and has a colored pattern (pixels 2 and black matrix 3) that has excellent solvent resistance.

[0101] <Image display element> The image display element of this embodiment is equipped with the above-described color filter. Examples of the image display element include a liquid crystal display element and an organic EL display element. In particular, the image display element of this embodiment is capable of high brightness display by being equipped with the above-described color filter. [Example]

[0102] The present invention will be explained in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[0103] An example of the synthesis of copolymer (A) is shown below.

[0104] [Synthesis Example 1] 700 g of 3-methoxy-1-butanol was placed in a flask equipped with a stirrer, a dropping funnel, a condenser, a thermometer, and a gas inlet tube, and the mixture was stirred while replacing the atmosphere with nitrogen and heated to 105°C. Next, a monomer mixture consisting of 9.4 g (0.1 mol) of methacrylic acid and 256.1 g (0.9 mol) of 3-methacryloyloxypropylmethyldiethoxysilane, to which 34.5 g of dimethyl 2,2'-azobis(isobutyrate) (polymerization initiator) was added, was added dropwise from the dropping funnel to the flask. After the dropwise addition was completed, the mixture was stirred at 105°C for 2 hours to carry out a copolymerization reaction, thereby obtaining a copolymer of Sample 1 (weight average molecular weight (Mw): 3500, number average molecular weight (Mn): 2300, molecular weight distribution (Mw / Mn): 1.5, acid value: 20.5 KOHmg / g, silyl group equivalent: 300 g / mol).

[0105] [Synthesis Examples 2 to 12, Comparative Synthesis Examples 1 to 15] Copolymerization reactions were carried out in the same manner as in Synthesis Example 1, except that the raw materials listed in Tables 1 and 2 were used, to obtain copolymers of Samples 2 to 27. The weight-average molecular weight (Mw), number-average molecular weight (Mn), molecular weight distribution (Mw / Mn), acid value, and silyl group equivalent of the obtained samples are shown in Tables 1 and 2.

[0106] [Table 1]

[0107] [Table 2]

[0108] <(A) Evaluation of the copolymer> (1) Storage stability Using the obtained samples 1 to 27, the storage stability was evaluated according to the following method. The sample was weighed out in 10 g portions into 20 ml glass containers to prepare samples, and the viscosity was measured. In this specification, viscosity refers to a value measured at 25°C and 20 rpm using an E-type viscometer (RE-80 manufactured by Toki Sangyo, rotor 1°34' x R24). Subsequently, these samples were each left to stand in an incubator maintained at 12°C for three months, and then the viscosity was measured again. The viscosity before and after the storage stability test was used to calculate the viscosity increase rate (the rate of increase in viscosity) according to the following formula: Viscosity increase rate = (([Viscosity after test] - [Viscosity before test]) / [Viscosity before test]) x 100% The criteria for this evaluation are as follows: ○: Viscosity increase rate less than 10% ×: Viscosity increase rate 10% or more The evaluation results of the storage stability are shown in Tables 4 and 5. When a copolymer having excellent storage stability is blended into a photosensitive resin composition, the storage stability of the photosensitive resin composition itself can be improved.

[0109] Using the obtained Samples 1 to 12 as copolymers (A) and Samples 13 to 27 as copolymers (A'), photosensitive resin compositions were prepared according to the following method.

[0110] <Preparation of Photosensitive Resin Composition> According to the ingredients and mixing ratios shown in Table 3, photosensitive resin compositions (Samples 28 to 54) were prepared using a dye (VALIFAST BLUE 2620) as the colorant (E). The amount of (A) copolymer (or (A') copolymer, the same applies below) in Table 3 does not include the solvent used in synthesizing (A) copolymer, and the amount of (B) solvent in Table 3 is the sum of the solvent used in synthesizing (A) copolymer and the additional propylene glycol monomethyl ether.

[0111] [Table 3]

[0112] <Evaluation of Photosensitive Resin Composition> (1) Developability The prepared photosensitive resin compositions (Examples 1 to 12 and Comparative Examples 1 to 15) were applied onto 5 cm square glass substrates (alkali-free glass substrates) by spin coating so that the thickness after exposure would be 2.5 μm, and the substrates were heated at 100°C for 3 minutes to volatilize the solvent, forming coating films on the glass substrates. Next, a photomask having a line and space pattern with a width of 3 to 100 μm was placed 100 μm away from the coating film, and light from an ultra-high pressure mercury lamp was irradiated through the photomask at 200 mJ / cm. 2 The unexposed areas were then removed using Semiclean DL-A10 developer (diluted 5 times) at a temperature of 23°C, a pressure of 0.1 MPa, and a development time of 60 seconds. The coating film with the pattern prepared as described above was observed under a microscope to evaluate the minimum line width (minimum developed dimension) of the developed area and the presence or absence of residue in the unexposed area. For the minimum developed dimension, cases where the pattern could not be developed well and could not be distinguished were marked with an "x." The presence or absence of residue is indicated according to the following criteria. Residue: No residue in unexposed area Residue ×: Residue found in unexposed area The evaluation results of the above-mentioned developability are shown in Tables 4 and 5.

[0113] (2) Pencil hardness The prepared photosensitive resin compositions (Examples 1 to 12 and Comparative Examples 1 to 15) were applied onto 5 cm square glass substrates (alkali-free glass substrates) using a spin coater method, and the solvent was evaporated by heating at 100°C for 3 minutes to form a coating film on the glass substrate. Next, the coating film was exposed to light with a wavelength of 365 nm to photocure the coated surface. Next, the film was left to stand in a dryer at 230°C for 30 minutes for heat treatment (post-baking), yielding a cured resin film with a thickness of 2.5 μm. The pencil hardness of the cured resin film prepared as described above was measured using a pencil hardness tester (No. 553-M, manufactured by Yasuda Seiki Seisakusho) in accordance with JIS K5600-5-4. The criteria are as follows: ○:Pencil hardness 3H or higher ×: Pencil hardness less than 3H The results of the pencil hardness evaluation are shown in Tables 4 and 5.

[0114] (3) Solvent resistance The prepared photosensitive resin compositions (Examples 1 to 12 and Comparative Examples 1 to 15) were applied onto 5 cm square glass substrates (alkali-free glass substrates) using a spin coater method, and the solvent was evaporated by heating at 100°C for 3 minutes to form a coating film on the glass substrate. Next, the coating film was exposed to light with a wavelength of 365 nm to photocure the coated surface. Next, the film was left to stand in a dryer at 230°C for 30 minutes for heat treatment (post-baking), yielding a cured resin film with a thickness of 2.5 μm. 200 mL of N-methyl-2-pyrrolidone was placed in a 500 mL glass bottle with a lid and left to stand at 60° C. The test piece with the cured resin film was immersed in the bottle and then left to stand for 30 minutes while maintaining the temperature at 60° C. The color change (ΔE*ab) of the test piece before and after immersion in N-methyl-2-pyrrolidone was measured using a spectrophotometer (UV-1650PC, manufactured by Shimadzu Corporation). The criteria for this evaluation are as follows: ○: ΔE*ab is less than 3.0 ×: ΔE*ab is 3.0 or more The evaluation results of the solvent resistance are shown in Tables 4 and 5.

[0115] [Table 4]

[0116] [Table 5]

[0117] The results in Tables 4 and 5 show that the (A) copolymers obtained in Synthesis Examples 1 to 12 exhibited excellent storage stability, and the photosensitive resin compositions (Examples 1 to 12) using the (A) copolymers obtained in Synthesis Examples 1 to 12 provided cured resin films with excellent hardness and patterns with excellent alkaline developability and solvent resistance. In contrast, the (A') copolymers of Comparative Synthesis Examples 1 to 9, which used (A'-1) 3-methacryloyloxypropyltriethoxysilane instead of the (A-1) compound, did not have sufficient storage stability. It is believed that the deterioration in storage stability was due to the fact that triethoxy-type alkoxysilyl groups undergo crosslinking more rapidly than diethoxy-type alkoxysilyl groups. Furthermore, Comparative Example 10, which used the (A') copolymer of Comparative Synthesis Example 10, which had an acid value of 0, did not provide sufficient developability. Comparative Examples 11 to 13, which used the copolymers (A') of Comparative Synthesis Examples 11 to 13, which contained a low content of the structural unit (a-1) derived from a polymerizable unsaturated compound having an alkoxysilyl group, resulted in poor developability due to an insufficient amount of developing groups, as well as poor hardness and solvent resistance. This is presumably due to the high content of structural unit (a-2), which resulted in dissolution of both exposed and unexposed areas of the coating film in the pattern, and the low content of structural unit (a-1), which resulted in a low degree of crosslinking and inability to obtain a sufficiently cured product. The copolymers (A') of Comparative Synthesis Examples 14 and 15, which did not contain at least one selected from primary alcohols having 3 to 10 carbon atoms and secondary alcohols having 3 to 10 carbon atoms, also did not have sufficient storage stability. This is presumably due to the fact that tertiary alcohol solvents and non-alcohol solvents have poor solvation with water, which facilitates the hydrolysis reaction of the alkoxysilyl groups.

[0118] According to the present invention, a photosensitive resin composition containing a copolymer is provided that has good developability, can form a cured resin film that is excellent in hardness and solvent resistance, and has excellent storage stability. Also provided is a cured resin film that is excellent in hardness and solvent resistance, and an image display device comprising the same. The photosensitive resin composition can be preferably used as a transparent film, a protective film, an insulating film, an overcoat, a photospacer, a black matrix, a black column spacer, or a resist for a color filter.

Claims

1. (A) a copolymer; (B) a reactive diluent; and (C) a photopolymerization initiator; (D) a solvent; A photosensitive resin composition comprising: The copolymer (A) contains a structural unit (a-1) represented by the following formula (1) and a structural unit (a-2) derived from a polymerizable unsaturated compound and having an acid group, the content of the structural unit (a-1) in all structural units of the copolymer (A) is more than 50 mol%, The photosensitive resin composition, wherein the solvent (D) contains at least one selected from the group consisting of a primary alcohol having 3 to 10 carbon atoms and a secondary alcohol having 3 to 10 carbon atoms. 【Chemical 1】 (In formula (1), R 1 represents a hydrogen atom or a methyl group, R 2 ~R 4 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms, and n is an integer from 1 to 10. 2 ~R 4 At least one of R is an alkoxy group having 1 to 6 carbon atoms, 2 ~R 4 At least one of the groups is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

2. In the structural unit (a-1) represented by the formula (1), R 2 ~R 4 two of which are alkoxy groups having 1 to 2 carbon atoms, and R 2 ~R 4 2. The photosensitive resin composition according to claim 1, wherein one of the groups is an alkyl group having 1 to 2 carbon atoms.

3. the acid group possessed by the structural unit (a-2) in the copolymer (A) is a carboxy group, 3. The photosensitive resin composition according to claim 1, wherein the copolymer (A) has an acid value of 15 to 300 KOH mg / g.

4. 4. The photosensitive resin composition according to claim 1, wherein the structural unit (a-2) in the copolymer (A) is a structural unit derived from (meth)acrylic acid.

5. 5. The photosensitive resin composition according to claim 1, wherein the total content of the primary alcohol having 3 to 10 carbon atoms and the secondary alcohol having 3 to 10 carbon atoms in the solvent (D) is 20 to 100 mass%.

6. the weight average molecular weight of the copolymer (A) is 1,000 to 50,000; 6. The photosensitive resin composition according to claim 1, wherein the molecular weight distribution (Mw / Mn) of the copolymer (A) is 1.3 to 3.

0.

7. The photosensitive resin composition according to any one of claims 1 to 6, further comprising (E) a colorant.

8. When the total amount of the components excluding the (D) solvent is 100 parts by mass, the content of the copolymer (A) is 5 to 85 parts by mass, The content of the (B) reactive diluent is 5 to 85 parts by mass, The photosensitive resin composition according to any one of claims 1 to 7, wherein the content of the photopolymerization initiator (C) is 0.1 to 30 parts by mass.

9. A cured resin film comprising a cured product of the photosensitive resin composition according to any one of claims 1 to 8.

10. A color filter having a colored pattern made of a cured product of the photosensitive resin composition according to claim 7.

11. An image display device comprising the color filter according to claim 10.

Images