Copolymer, photosensitive resin composition, resin cured film, and image display element

Abstract

A copolymer containing a structural unit (a) having an acid group, and a structural unit (b) having a group represented by formula (1-1) (in formula (1-1), R1 is a hydrogen atom or a hydrocarbon group having 1-20 carbon atoms, R2 and R3 are each independently a hydrogen atom or a hydrocarbon group having 1-20 carbon atoms, and * represents a site linked to a residue obtained by removing the group represented by formula (1-1) from the structural unit (b)). # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a copolymer, a photosensitive resin composition, a photosensitive coloring composition, a resin cured film and an image display element. Background Art

[0002] In recent years, from the perspective of resource and energy conservation, photosensitive resin compositions that can be cured by active energy lines such as ultraviolet rays and electron beams have been widely used in the fields of various coatings, printings, coatings, adhesives, etc. Even in the field of electronic materials such as printed circuit boards, photosensitive resin compositions that can be cured by active energy lines are also used in solder resists and color filter resists. The properties required for curable photosensitive resin compositions are becoming more and more diverse and complex, requiring short-time curing properties considering productivity, and requiring low-temperature curing properties that can suppress thermal damage to the applied components.

[0003] Color filters are generally composed of the following: a transparent substrate such as a glass substrate; red (R), green (G) and blue (B) pixels formed on the transparent substrate; a black matrix formed at the boundary of the pixels; and a protective film formed on the pixels and the black matrix. A color filter having such a structure is usually manufactured by sequentially forming a black matrix, pixels and a protective film on a transparent substrate. Various methods have been proposed as a method for forming pixels and a black matrix (hereinafter referred to as "coloring patterns"). Among them, a pigment / dye dispersion method in which a photosensitive resin composition is used as a resist and a coloring pattern is prepared by a photolithography method of repeated coating, exposure, development and baking is the current mainstream method because it can obtain a coloring pattern with excellent durability and fewer defects such as pinholes.

[0004] The photosensitive resin composition used in the general photolithography method contains: an alkali-soluble resin, a reactive diluent, a photopolymerization initiator, a colorant and a solvent. Although the pigment / dye dispersion method has the above advantages, the baking is repeated to form the black matrix, R, G and B patterns, so the photosensitive resin composition is required to have high heat resistance, and there is often a problem that the types of colorants that can be used are limited to those that can withstand high baking temperatures.

[0005] In recent years, a photosensitive resin composition having low-temperature curing properties has been proposed, which can also be used for components with low heat resistance such as organic EL. For example, Patent Document 1 discloses a coloring composition having a specific partial structure and a hydroxyl group as a photosensitive resin composition, which can obtain a cured product with excellent solvent resistance even under low-temperature curing conditions and is suitable for use in applications such as color filters.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2021-102759 Summary of the invention

[0009] Problems to be solved by the invention

[0010] However, in recent years, there has been a demand for further low-temperature curing properties, but this has resulted in insufficient film curing, and there is a concern that solvent resistance may be reduced due to a trade-off relationship. Therefore, it is required that the cured product has high solvent resistance even when cured at low temperatures. In addition, the photosensitive resin composition is also required to have excellent developability.

[0011] The present invention is made to solve the above-mentioned problems, and its object is to provide a copolymer that can provide a resin cured film having excellent solvent resistance and contributes to the improvement of developability, and a photosensitive resin composition and a photosensitive coloring composition using the copolymer. A further object of the present invention is to provide a resin cured film having excellent solvent resistance, and an image display element having the resin cured film.

[0012] [Methods to solve the problem]

[0013] The present invention includes the following aspects.

[0014] [1]. A copolymer having:

[0015] The structural unit (a) having an acid group, and

[0016] A structural unit (b) having a group represented by the following formula (1-1) or the following formula (1-2),

[0017]

[0018] In formula (1-1), R 1 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, * represents a site connected to the residue after removing the group of formula (1-1) from the structural unit (b),

[0019]

[0020] In formula (1-2), R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 4is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and * represents a site connected to the residue obtained by removing the group of the formula (1-2) from the structural unit (b).

[0021] [2] The copolymer described in [1] further has:

[0022] A structural unit (c) having a hydroxyl group, and

[0023] A structural unit (d) having a blocked isocyanate group.

[0024] [3] The copolymer according to [2], wherein the blocking agent of the structural unit (d) having a blocked isocyanate group is at least one selected from 3,5-dimethylpyrazole, butanone oxime, methyl 4-hydroxybenzoate, methyl 2-hydroxybenzoate and 3,5-dimethylphenol.

[0025] [4] The copolymer according to [2], wherein the blocking agent of the structural unit (d) having a blocked isocyanate group has a carboxylic acid alkyl ester structure.

[0026] [5] The copolymer according to [2], wherein the structural unit (d) having a blocked isocyanate group has a group represented by the following formula (2) or a group represented by the following formula (3),

[0027]

[0028] In formula (2), R 5 and R 6 Each independently represents an alkyl group having 1 to 10 carbon atoms, n1 and n2 each independently represent an integer of 0 to 2, * represents a site connected to the residue after removing the blocked isocyanate group from the structural unit (d),

[0029]

[0030] In formula (3), R 7 and R 8 Each independently represents an alkyl group having 1 to 10 carbon atoms, n3 and n4 each independently represent an integer of 0 to 2, and * represents a site to which the residue after removing the blocked isocyanate group from the structural unit (d) is bonded.

[0031] [6] The copolymer described in [1] to [5] further comprises another structural unit (e) other than the structural units (a) to (d),

[0032] The structural unit (e) is a structural unit derived from an alkyl (meth)acrylate having an alkyl group with 1 to 12 carbon atoms.

[0033] [7] The copolymer described in [1] to [6], having an acid value of 10 to 300 KOHmg / g.

[0034] [8] The copolymer described in [1] to [7] contains 3 to 40 mol % of the structural unit (b).

[0035] [9] The copolymer described in [1] to [8], having a weight average molecular weight of 1,000 to 50,000,

[0036] The ethylenically unsaturated group equivalent is 300 to 8000 g / mol.

[0037]

[10] . A photosensitive resin composition comprising:

[0038] The copolymer (A) as the copolymer described in any one of [1] to [9],

[0039] Reactive diluent (B),

[0040] Photopolymerization initiator (C), and

[0041] Solvent (D).

[0042]

[11] The photosensitive resin composition according to

[10] , wherein, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B),

[0043] Containing 10 to 90 parts by weight of the copolymer (A),

[0044] Containing 10 to 90 parts by weight of the reactive diluent (B),

[0045] The photopolymerization initiator (C) is contained in an amount of 0.1 to 30 parts by weight.

[0046] The solvent (D) is contained in an amount of 30 to 1000 parts by mass.

[0047]

[12] A photosensitive coloring composition comprising the photosensitive resin composition described in

[10] or

[11] and a colorant (E).

[0048]

[13] The photosensitive coloring composition according to

[12] , wherein, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B),

[0049] Containing 10 to 90 parts by weight of the copolymer (A),

[0050] Containing 10 to 90 parts by weight of the reactive diluent (B),

[0051] The photopolymerization initiator (C) is contained in an amount of 0.1 to 30 parts by weight.

[0052] Containing 30 to 1000 parts by mass of the solvent (D),

[0053] The colorant (E) is contained in an amount of 3 to 80 parts by mass.

[0054]

[14] A cured resin film, comprising a cured product of the photosensitive resin composition described in

[10] or

[11] .

[0055]

[15] A cured resin film, comprising a cured product of the photosensitive coloring composition according to

[12] or

[13] .

[0056]

[16] . A color filter having a color pattern consisting of a cured product of the photosensitive coloring composition described in

[12] or

[13] .

[0057]

[17] . An image display element comprising the color filter described in

[16] .

[0058] [Effects of the invention]

[0059] According to the present invention, a copolymer that contributes to the improvement of developability and can obtain a resin cured film having excellent solvent resistance, and a photosensitive resin composition and a photosensitive coloring composition using the copolymer can be provided. In addition, a resin cured film having excellent solvent resistance, a color filter, and an image display element having the same, which are obtained by curing the photosensitive resin composition and the photosensitive coloring composition, can be provided. DETAILED DESCRIPTION

[0060] The embodiments of the present invention are described in detail below, but the present invention is not limited to the embodiments described below.

[0061] In the present specification, when "to" is used for a numerical range, it means that the numerical values ​​at both ends are the upper limit and the lower limit, respectively, and are included in the numerical range.

[0062] In the present specification, “(meth)acrylic acid” means methacrylic acid or acrylic acid, “(meth)acrylate” means acrylate or methacrylate, and “(meth)acryloyloxy” means acryloyloxy or methacryloyloxy.

[0063] In the present specification, the term "ethylenically unsaturated bond" means a double bond formed between carbon atoms other than carbon atoms forming an aromatic ring, and the term "ethylenically unsaturated group" means a group having an ethylenically unsaturated bond.

[0064] In the present specification, the term "structural unit" means a unit derived from a polymerizable compound used as a monomer or a unit obtained by further modifying a unit derived from a polymerizable compound used as a monomer.

[0065] (Copolymer (A))

[0066] The copolymer (A) of one embodiment contains: a structural unit (a) having an acid group and a structural unit (b) having a group represented by the following formula (1-1) or the following formula (1-2). Since the copolymer (A) contains the structural unit (b) having an ethylenically unsaturated group, when the copolymer (A) is used in a photosensitive resin composition, good photocurability can be formed and low-temperature curability can be improved. In addition, when the copolymer (A) is used together with the reactive diluent (B) described later, the ethylenically unsaturated group of the structural unit (b) reacts with the reactive diluent (B), and the cured film can form good adhesion to the substrate.

[0067]

[0068] (In formula (1-1), R 1 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and * represents a site connected to the residue after removing the group of formula (1-1) from the structural unit (b)

[0069]

[0070] (In formula (1-2), R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 4 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and * represents a site connected to the residue after removing the group of formula (1-2) from the structural unit (b).

[0071] If necessary, the copolymer (A) may further contain a structural unit (c) having a hydroxyl group and a structural unit (d) having a blocked isocyanate group. If necessary, the copolymer (A) may further contain another structural unit (e) other than the structural units (a) to (d).

[0072] [Structural unit having an acid group (a)]

[0073] The structural unit (a) having an acid group (also referred to as "structural unit (a)") is not particularly limited as long as it is a structural unit having an acid group without an ethylenically unsaturated group. Since the copolymer (A) contains the structural unit (a) having an acid group, when the copolymer (A) is used in a photosensitive resin composition, good alkali developability can be formed. Examples of the acid group include a carboxyl group, a sulfonic acid group, and a phosphonic acid group. Among these acid groups, a carboxyl group is preferably used as the acid group possessed by the structural unit (a) in terms of easy availability.

[0074] The structural unit (a) having an acid group is preferably a structural unit derived from a monomer (ma) having an acid group and an ethylenically unsaturated bond (hereinafter also referred to as a monomer (ma)). Specific examples of the monomer (ma) include unsaturated carboxylic acids or anhydrides thereof such as (meth)acrylic acid, α-bromo(meth)acrylic acid, (meth)acrylic acid β-furanyl ester, crotonic acid, propiolic acid, cinnamic acid, α-cyanocinnamic acid, maleic acid, maleic anhydride, monomethyl maleate, monoethyl maleate, monoisopropyl maleate, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, and citraconic anhydride; unsaturated sulfonic acids such as 2-acrylamide-2-methylpropanesulfonic acid, tert-butylacrylamidesulfonic acid, and p-styrenesulfonic acid; unsaturated phosphonic acids such as vinylphosphonic acid, etc. The monomer (ma) is preferably an unsaturated carboxylic acid or anhydride thereof, more preferably (meth)acrylic acid or a (meth)acrylate having a carboxylic acid group, and more preferably (meth)acrylic acid.

[0075] The monomer (ma) having an acid group and an ethylenically unsaturated bond may be used alone or in combination of two or more.

[0076] The content of the structural unit (a) is preferably 5 to 50 mol%, more preferably 8 to 40 mol%, and more preferably 10 to 30 mol% relative to the total structural units of the copolymer (A). When the content of the structural unit (a) is 5 mol% or more, the photosensitive resin composition using the copolymer (A) can form good developability. When the content of the structural unit (a) is 50 mol% or less, since the content of the structural unit (b) can be sufficiently ensured, the effect caused by the structural unit (b) can be fully ensured.

[0077] [Structural unit (b) having a group represented by formula (1-1) or formula (1-2)]

[0078] The structural unit (b) having a group represented by the formula (1-1) or (1-2) (also simply referred to as "structural unit (b)") is a structural unit having a group represented by the following formula (1-1) or (1-2).

[0079]

[0080] (In formula (1-1), R 1 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and * represents a site connected to the residue after removing the group of formula (1-1) from the structural unit (b)

[0081]

[0082] (In formula (1-2), R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 4 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and * represents a site connected to the residue after removing the group of formula (1-2) from the structural unit (b)

[0083] The group represented by formula (1-1) may be more than one type. 1 can be different, and the R of each structural unit 2 The R of each structural unit may be different. 3 The same applies to the group represented by formula (1-2).

[0084] In formula (1-1) and formula (1-2), R 1 and R 4 Each independently represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, preferably a hydrocarbon group having 1 to 5 carbon atoms. In particular, a hydrocarbon group having 1 to 3 carbon atoms is more preferred because it is easy to cause a reaction from the structural unit (pb) described later to the structural unit (b) having a group represented by the formula (1-1) or (1-2). 1 and R 4 It is preferably an alkyl group having 1 to 5 carbon atoms, preferably a methyl group or an ethyl group, and particularly preferably an ethyl group. 1 and R 4 They may be the same or different. R is preferably 1 and R 4 same.

[0085] In formula (1-1) and formula (1-2), R 2 and R 3 Each independently represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, preferably a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms. In particular, since it is easy to cause a reaction from the structural unit (pb) described later to the structural unit (b) having a group represented by the formula (1-1) or (1-2), a hydrogen atom or a methyl group is more preferred, and a hydrogen atom is particularly preferred. 2 and R 3 Since the monomer (m-pb) described later can be easily produced, R 2 and R 3 Preferably the same.

[0086] The structural unit (b) can be obtained by subjecting the structural unit (pb) having a group represented by the following formula (1) (also simply referred to as "structural unit (pb)") to dealcoholization and decarboxylation reactions in a solvent (PD) using a basic catalyst.

[0087]

[0088] (In formula (1), R 1 and R 4 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and * represents a site connected to the residue after removing the group of formula (1) from the structural unit (pb)

[0089] The structural unit (pb) is a structural unit derived from a monomer (m-pb) having a group represented by the above formula (1) (also simply referred to as "monomer (m-pb)"). The structural unit (pb) may be used alone or in combination of two or more.

[0090] The monomer (m-pb) is a monomer having an ethylenically unsaturated bond and a group represented by the above formula (1).

[0091] In formula (1), R 1 , R 2 , R 3 and R 4 Same as above.

[0092] Examples of the monomer (m-pb) include compounds obtained by urethanization reaction of an isocyanate group in an isocyanate compound having an ethylenically unsaturated group such as a vinyl group or a (meth)acryloyloxy group in the molecule with a hydroxyl group in a hydroxyl group-containing compound represented by the following formula (4).

[0093]

[0094] (In formula (4), R 1 , R 2 , R 3 and R 4 With R in formula (1) 1 , R 2 , R 3 and R 4 same)

[0095] As a method for subjecting the above-mentioned isocyanate compound having an ethylenically unsaturated group and the hydroxyl-containing compound represented by formula (4) to urethanization reaction, a conventionally known method can be used.

[0096] The above-mentioned urethanization reaction can be carried out in the presence or absence of a solvent. When the above-mentioned urethanization reaction is carried out using a solvent, the solvent used may be any solvent inert to isocyanate groups, and a known solvent may be used.

[0097] The above-mentioned urethanization reaction is generally preferably carried out at a temperature of -10°C to 90°C, more preferably at a temperature of 5°C to 70°C, and even more preferably at a temperature of 10°C to 40°C.

[0098] When the above-mentioned urethanization reaction is carried out, a urethanization catalyst such as dibutyltin dilaurate and a polymerization inhibitor such as phenothiazine, hydroquinone monomethyl ether, and 2,6-di-tert-butyl-4-methylphenol (BHT) may be used as necessary.

[0099] Examples of the isocyanate compound having an ethylenically unsaturated group used as a raw material of the monomer (m-pb) include isocyanate compounds represented by the following formula (5).

[0100]

[0101] (In formula (5), R 9 represents a hydrogen atom or a methyl group, R 10 Indicates -CO-, -COOR 11 -(where R 11 is an alkylene group having 1 to 6 carbon atoms) or -COO-R 12 O-CONH-R 13 -(where R 12 is an alkylene group having 2 to 6 carbon atoms, R 13 is an alkylene group having 2 to 12 carbon atoms or an arylene group having 6 to 12 carbon atoms which may have a substituent)

[0102] In the isocyanate compound represented by formula (5), R 10 Preferably -COOR 11 -, R 11 More preferably, it is an alkylene group having 1 to 4 carbon atoms.

[0103] Specific examples of the isocyanate compound represented by the formula (5) include 2-isocyanateethyl (meth)acrylate, 2-isocyanatepropyl (meth)acrylate, 3-isocyanatepropyl (meth)acrylate, 2-isocyanate-1-methylethyl (meth)acrylate, 2-isocyanate-1,1-dimethylethyl (meth)acrylate, 4-isocyanatecyclohexyl (meth)acrylate, and methacryloyl isocyanate.

[0104] As the isocyanate compound used as the raw material of the monomer (M-PB), a reaction product obtained by reacting a hydroxyalkyl (meth)acrylate with a diisocyanate compound in equimolar amounts (hydroxyalkyl (meth)acrylate: diisocyanate compound = 1 mol: 1 mol) can be used.

[0105] The alkyl group of the hydroxyalkyl (meth)acrylate is preferably an ethyl group or an n-propyl group, and more preferably an ethyl group, from the viewpoint of easy preparation of the isocyanate compound and simplicity of the reaction.

[0106] Examples of the diisocyanate compound include hexamethylene diisocyanate, 2,4- (or 2,6-) toluene diisocyanate (TDI), 4,4′-diphenylmethane diisocyanate (MDI), 3,5,5-trimethyl-3-isocyanatomethylcyclohexyl isocyanate (IPDI), m- (or p-) xylene diisocyanate, 1,3- (or 1,4-) bis (isocyanatomethyl) cyclohexane, and lysine diisocyanate.

[0107] Examples of the other isocyanate compounds used as the monomer (M-PB) raw material include 1,1-bis(methacryloyloxymethyl)methyl isocyanate, 1,1-bis(methacryloyloxymethyl)ethyl isocyanate, 1,1-bis(acryloyloxymethyl)methyl isocyanate, and 1,1-bis(acryloyloxymethyl)ethyl isocyanate.

[0108] As the isocyanate compound used as the raw material of the monomer (M-PB), from the viewpoint of low-temperature curing property, an isocyanate group-containing (meth)acrylate is preferred, and 2-isocyanateethyl (meth)acrylate, 2-isocyanatepropyl (meth)acrylate, 3-isocyanatepropyl (meth)acrylate, 2-isocyanate-1-methylethyl (meth)acrylate, 1,1-bis(methacryloyloxymethyl)ethyl isocyanate, 2-isocyanate-1,1-dimethylethyl (meth)acrylate, 4-isocyanatecyclohexyl (meth)acrylate and methacryloyl isocyanate are further preferred, and 2-isocyanateethyl (meth)acrylate, 2-isocyanatepropyl (meth)acrylate and 1,1-bis(methacryloyloxymethyl)ethyl isocyanate are further preferred.

[0109] Examples of the hydroxyl-containing compound represented by formula (4) used as a raw material for the monomer (M-PB) include malic acid esters, 2-methyl malic acid esters, 3-methyl malic acid esters, 2,3-dimethyl malic acid esters, etc. Among them, malic acid esters are preferred from the viewpoint of ease of conversion reaction to the structural unit (b) having a group represented by formula (1-1) or formula (1-2) and easy availability.

[0110] The number of carbon atoms in the two ester sites contained in the hydroxyl group-containing compound represented by formula (4) (-COOR 1 and COOR 4 R 1 and R 4The number of carbon atoms) of each of the above-mentioned groups is 1 to 20, preferably 1 to 5, and more preferably 1 to 3.

[0111] The hydroxyl group-containing compound represented by formula (4) is particularly preferably diethyl malate from the viewpoint of easy availability.

[0112] Specifically, the monomer (M-PB) is preferably one or more selected from 2-[(diethylmalate)carbonylamino]ethyl acrylate, [(diethylmalate)carbonylamino]methyl acrylate, 2-[(diethylmalate)carbonylamino]propyl acrylate and 2-[(diethylmalate)carbonylamino]butyl acrylate. In terms of ease of production, 2-[(diethylmalate)carbonylamino]ethyl acrylate is particularly preferred.

[0113] The content of the structural unit (b) is preferably 3 mol% or more, more preferably 5 mol% or more, and more preferably 10 mol% or more, relative to the total structural units of the copolymer (A). The content of the structural unit (b) is preferably 40 mol% or less, more preferably 35 mol% or less, and more preferably 30 mol% or less, relative to the total structural units of the copolymer (A). The combination of these lower limits and upper limits can be any combination. The content of the structural unit (b) is preferably 3 to 40 mol%, more preferably 5 to 35 mol%, and more preferably 10 to 30 mol%, relative to the total structural units of the copolymer (A). When the content of the structural unit (b) is 3 mol% or more, the photosensitive resin composition using the copolymer (A) can form good low temperature curing and developability. When the content of the structural unit (b) is 40 mol% or less, the content of the structural unit (a) can be fully ensured, and sufficient developability can be formed. The content of the structural unit (b) is a value calculated based on the feed ratio of the monomer (m-pb) used when producing the resin precursor (PA) described later to all the monomers used when producing the resin precursor (PA). That is, the content of the structural unit (b) also includes the content of the structural unit (pb).

[0114] [Structural unit having a hydroxyl group (c)]

[0115] The structural unit (c) having a hydroxyl group (also referred to as "structural unit (c)") is not limited as long as it does not have an acid group, an ethylenically unsaturated group, and a blocked isocyanate group, but has a hydroxyl group. The copolymer (A) has "structural unit (c) having a hydroxyl group" and can be cross-linked with the structural unit (d) having a blocked isocyanate group described later when heated. Therefore, when the copolymer (A) is used in a photosensitive resin composition, even if it is thermally cured under low temperature conditions, the cured product can still have good solvent resistance.

[0116] The structural unit (c) having a hydroxyl group is preferably a structural unit derived from a monomer (mc) having a hydroxyl group and an ethylenically unsaturated group (hereinafter also referred to as a monomer (mc)). Specific examples of the monomer (mc) include (meth)acrylate derivatives having a hydroxyl group, specifically, (meth)acrylate-2-hydroxyethyl, (meth)acrylate-2-hydroxypropyl, (meth)acrylate-2-hydroxybutyl, (meth)acrylate-2,3-dihydroxypropyl, (meth)acrylate-4-hydroxybutyl, and (meth)acrylate-hydroxyalkyl esters; (meth)acrylate-2-hydroxy-3-phenoxypropyl, and the like. Among them, from the viewpoint of reactivity during synthesis of the copolymer (A), low-temperature curing properties of the photosensitive resin composition containing the copolymer (A), and easy availability, hydroxyalkyl (meth)acrylate is preferred. As the hydroxyalkyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate are preferred, and 4-hydroxybutyl (meth)acrylate is more preferred from the viewpoint of lowering the glass transition temperature of the copolymer (A).

[0117] The monomer (mc) having a hydroxyl group and an ethylenically unsaturated group may be used alone or in combination of two or more.

[0118] The content of the structural unit (c) is preferably 3 to 40 mol%, more preferably 5 to 30 mol%, and more preferably 8 to 25 mol% relative to all the structural units of the copolymer (A). When the content of the structural unit (c) is 3 mol% or more, the crosslinking amount of the hydroxyl group possessed by the structural unit (c) and the blocked isocyanate group possessed by the structural unit (d) can be fully ensured. As a result, the low-temperature curing property of the photosensitive resin composition using the copolymer (A) is improved. When the content of the structural unit (c) is 40 mol% or less, since the contents of the structural units (a) and the structural units (b) can be fully ensured, sufficient developability of the cured product can be formed. In addition, since the content of the structural unit (d) can be fully ensured, the crosslinking amount with the structural unit (c) can be fully ensured.

[0119] [Structural unit having a blocked isocyanate group (d)]

[0120] The structural unit (d) having a blocked isocyanate group (also referred to as "structural unit (d)") is not particularly limited as long as it does not have an acid group and an ethylenically unsaturated group and does not belong to the structural unit (pb), and is a structural unit having a blocked isocyanate group. The copolymer (A) is cross-linked with the structural unit (c) having a hydroxyl group when heated due to the "structural unit (d) having a blocked isocyanate group". The cross-linking is formed, for example, by the reaction of the isocyanate group generated by the dissociation of the blocking agent and the hydroxyl group. When the blocking agent is a compound having a carboxylic acid alkyl ester structure, the cross-linking can be formed by the ester exchange between the carboxylic acid alkyl ester structure and the hydroxyl group described later, even if the dissociation of the blocking agent does not occur. Therefore, when the copolymer (A) is used in a photosensitive resin composition, even if it is thermally cured under low temperature conditions, the cured product can still form good solvent resistance.

[0121] The structural unit (d) having a blocked isocyanate group has a structure in which the isocyanate group is blocked by a blocking agent. The reaction between the isocyanate group and the blocking agent can be carried out regardless of the presence of a solvent. When a solvent is used, it is necessary to use a solvent that is inert to the isocyanate group. During the blocking reaction, organic metal salts of tin, zinc, lead, etc., tertiary amines, etc. can be used as catalysts. The blocking reaction can generally be carried out at -20 to 150°C, but is preferably carried out at 0 to 100°C.

[0122] Examples of the blocking agent for blocking the isocyanate group include lactam compounds such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, and β-propiolactam; alcohol compounds such as methanol, ethanol, propanol, butanol, ethylene glycol, methyl cellosolve, butyl cellosolve, methyl carbitol, benzyl alcohol, phenyl cellosolve, furfuryl alcohol, and cyclohexanol; phenol compounds such as phenol, cresol, 2,6-dimethylphenol, 3,5-dimethylphenol, ethylphenol, o-isopropylphenol, butylphenol such as p-tert-butylphenol, p-tert-octylphenol, nonylphenol, dinonylphenol, styrenated phenol, methyl 2-hydroxybenzoate, methyl 4-hydroxybenzoate, thymol, 1-naphthol, p-nitrophenol, and p-chlorophenol; dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, and the like; esters, acetylacetone and the like; thiol compounds such as butanethiol, thiophenol, tert-dodecyl mercaptan, etc.; amine compounds such as diphenylamine, phenylnaphthylamine, aniline, carbazole, etc.; amide compounds such as acetamidobenzene, acetanilide, acetamide, benzamide, etc.; imide compounds such as succinimide and maleimide; imidazole compounds such as imidazole, 2-methylimidazole, 2-ethylimidazole, etc.; pyrazole compounds such as pyrazole, 3,5-dimethylpyrazole, etc.; urea compounds such as urea, thiourea, ethyleneurea, etc.; aminocarbamic acid compounds such as N-phenylcarbamic acid phenyl ester and 2-oxazolinone; imine compounds such as ethyleneimine and polyethyleneimine; oxime compounds such as formaldehyde oxime, acetaldehyde oxime, acetone oxime, butanone oxime, methyl isobutyl ketone oxime, cyclohexanone oxime, etc.; pyrosulfites such as sodium pyrosulfite and potassium pyrosulfite, etc.

[0123] The blocking agent may be used alone or in combination of two or more.

[0124] In one embodiment, the blocking agent is preferably a blocking agent having a dissociation rate of the blocked isocyanate group of 5 to 99% by mass when subjected to a heat treatment at 100° C. for 30 minutes from the viewpoint of improving the low-temperature curability and solvent resistance of the photosensitive resin composition. It is further preferably one or more selected from 3,5-dimethylpyrazole, butanone oxime, methyl 4-hydroxybenzoate, methyl 2-hydroxybenzoate and 3,5-dimethylphenol, and more preferably 3,5-dimethylpyrazole.

[0125] In this specification, the dissociation rate of the blocked isocyanate group is a value obtained by measuring the mass reduction ratio of the compound containing the blocked isocyanate group by HPLC analysis after adding 1 mass % of dibutyltin laurate and 3 mass % of phenothiazine (polymerization inhibitor) to a n-octanol solution containing a compound containing a blocked isocyanate group, heating the solution at 100° C. for 30 minutes. As the compound containing the blocked isocyanate group, a compound obtained by blocking the isocyanate group of the measurement object 2-ethyl acrylate with a blocking agent is used. When a compound containing a blocked isocyanate group having a dissociation rate in the above range is used, the stability of the copolymer (A) during synthesis can be fully ensured, and the baking temperature during the preparation of the cured film can be set to a sufficiently low temperature, and the solvent resistance of the cured film can also be fully ensured.

[0126] In one embodiment, as a capping agent, from the viewpoint of improving the low-temperature curing property and solvent resistance of the photosensitive resin composition, a capping agent having an alkyl carboxylate structure is also preferred. In this case, the structural unit (d) having a blocked isocyanate group has an alkyl carboxylate structure. The alkyl carboxylate structure means a structure having an alkoxycarbonyl group, preferably a structure having an alkoxycarbonyl group having 1 to 10 carbon atoms in the alkyl group. The alkoxycarbonyl group is formed by heating the photosensitive resin composition containing the copolymer (A) to form a cross-linked structure by ester exchange with the hydroxyl group possessed by the structural unit (c). Therefore, a photosensitive resin composition using a copolymer (A) containing a structural unit having an alkyl carboxylate structure can obtain a cured film having excellent solvent resistance even when cured at a low temperature of 50°C to 150°C.

[0127] The structural unit having a carboxylic acid alkyl ester structure is more preferably a structural unit having a group represented by the following formula (2) or a group represented by the following formula (3).

[0128]

[0129] (In formula (2), R 5 and R 6 Each independently represents an alkyl group having 1 to 10 carbon atoms, n1 and n2 each independently represent an integer of 0 to 2, and * represents a site connected to the residue after removing the blocked isocyanate group from the structural unit (d)

[0130]

[0131] (In formula (3), R 7 and R 8Each independently represents an alkyl group having 1 to 10 carbon atoms, n3 and n4 each independently represent an integer of 0 to 2, and * represents a site connected to the residue after removing the blocked isocyanate group from the structural unit (d)

[0132] The group represented by formula (2) may be more than one type. 5 can be different, and the R of each structural unit 6 The n1 of each structural unit may be different from each other, and the n2 of each structural unit may be different from each other. The same applies to the group represented by formula (3).

[0133] In the above formula (2), R 5 and R 6 Each R is independently an alkyl group having 1 to 10 carbon atoms. 5 and R 6 Each of the following is independently preferably an alkyl group having 2 to 6 carbon atoms, and more preferably an alkyl group having 2 to 3 carbon atoms. 5 and R 6 Most preferably both are ethyl.

[0134] In R 5 and R 6 When R is ethyl, when the photosensitive resin composition containing the copolymer (A) is thermally cured, 5 and R 6 Ethanol is generated by transesterification with the hydroxyl group of the structural unit (c). Ethanol generated when the photosensitive resin composition is thermally cured is preferably generated because it can be easily evaporated by thermally curing the photosensitive resin composition by heating.

[0135] In the above formula (2), n1 and n2 each independently represent an integer of 0 to 2. n1 and n2 each independently represent preferably 0 or 1, and more preferably both represent 0.

[0136] In the above formula (3), R 7 and R 8 Each R is independently an alkyl group having 1 to 10 carbon atoms. 7 An alkyl group having 2 to 6 carbon atoms is preferred, an alkyl group having 2 to 3 carbon atoms is more preferred, and an ethyl group is further preferred.

[0137] In R 7 When R is ethyl, when the photosensitive resin composition containing the copolymer (A) is thermally cured, 7 Ethanol is generated by transesterification with the hydroxyl group of the structural unit (c). Ethanol generated when the photosensitive resin composition is thermally cured is preferably generated because it can be easily evaporated by thermally curing the photosensitive resin composition by heating.

[0138] R 8An alkyl group having 1 to 6 carbon atoms is preferred, an alkyl group having 1 to 3 carbon atoms is more preferred, and a methyl group is even more preferred.

[0139] In the above formula (3), n3 and n4 each independently represent an integer of 0 to 2. n3 and n4 each independently represent preferably 0 or 1, and more preferably both represent 0.

[0140] From the viewpoint of easiness of transesterification with the hydroxyl group of the structural unit (c) and low-temperature curability of the photosensitive resin composition, the structural unit (d) preferably has a group represented by the formula (2).

[0141] The structural unit (d) having a blocked isocyanate group is preferably a structural unit derived from a monomer (md) having a blocked isocyanate group and an ethylenically unsaturated bond (also referred to as a monomer (md)). The monomer (md) can be used alone or in combination of two or more. Specifically, vinyl, (meth)acryloyloxy, etc. can be cited as the group having an ethylenically unsaturated bond.

[0142] Examples of the monomer (md) include a reaction product of an isocyanate compound having an ethylenically unsaturated group and a blocking agent. As the isocyanate compound having an ethylenically unsaturated group, the same isocyanate compound as the above-mentioned isocyanate compound used as a raw material for the monomer (m-pb) can be used.

[0143] The structural unit having a group represented by formula (2) or (3) is preferably a structural unit derived from a monomer having a group represented by formula (2) or (3) and an ethylenically unsaturated bond. Specific examples of the group having an ethylenically unsaturated bond include vinyl and (meth)acryloyloxy groups.

[0144] Examples of the monomer having a group represented by the formula (2) or (3) and an ethylenically unsaturated bond include a reaction product of an isocyanate compound having an ethylenically unsaturated group and a malonic acid diester or an acetoacetic acid ester.

[0145] As the isocyanate compound having an ethylenically unsaturated group, the same isocyanate compound as the above-mentioned isocyanate compound used as the raw material of the monomer (m-pb) can be used.

[0146] Examples of the malonic acid diester include dimethyl malonate, diethyl malonate, di(n-propyl) malonate, and di(isopropyl) malonate. From the viewpoint of availability, cost, and quality, diethyl malonate and dimethyl malonate are preferred.

[0147] Examples of the acetoacetate include methyl acetoacetate and ethyl acetoacetate.

[0148] Specific examples of the monomer having a group represented by formula (2) and an ethylenically unsaturated bond include Karenz (trademark) MOI-DEM (manufactured by Showa Denko K.K.) and Karenz (trademark) AOI-DEM (manufactured by Showa Denko K.K.).

[0149] The reaction of the isocyanate compound having an ethylenically unsaturated group with a malonic acid diester or an acetoacetic acid ester can be carried out in the presence or absence of a solvent. When a solvent is used for the above reaction, a solvent inert to the isocyanate group is used. In the above reaction, an organic metal salt of tin, zinc, lead, etc., a tertiary amine, etc. can be used as a catalyst.

[0150] The above reaction can be generally carried out at a temperature of -20 to 150°C, preferably at a temperature of 25 to 130°C. When the reaction temperature is -20°C or higher, a sufficient reaction rate can be achieved. On the other hand, when the reaction temperature is 150°C or lower, gelation of the raw material having a C=C (double bond) due to polymerization can be prevented.

[0151] The content of the structural unit (d) is preferably 5 to 45 mol%, more preferably 10 to 40 mol%, and more preferably 15 to 35 mol% relative to all the structural units of the copolymer (A). When the content of the structural unit (d) is 5 mol% or more, the amount of crosslinking between the blocked isocyanate group of the structural unit (d) and the hydroxyl group of the aforementioned structural unit (c) can be fully ensured. As a result, the low-temperature curing property of the photosensitive resin composition using the copolymer (A) is improved. When the content of the structural unit (d) is 45 mol% or less, since the contents of the structural units (a) and the structural units (b) can be fully ensured, the cured product can form sufficient developability. In addition, the content of the structural unit (c) can be fully ensured, so the amount of crosslinking with the structural unit (d) can be fully ensured.

[0152] [Other structural units (e) other than structural units (a) to (d)]

[0153] If necessary, the copolymer (A) may contain other structural units (e) (also referred to as "structural units (e)") other than the structural units (a) to (d), that is, structural units derived from monomers other than the monomers (ma), (m-pb), (mc) and (md). The structural unit (e) does not have an acid group, an ethylenically unsaturated group, a hydroxyl group and a blocked isocyanate group, and is a structural unit other than the structural units (a) to (d) and the structural unit (pb). By having the structural unit (e), the copolymer (A) can be given additional desired functions.

[0154] Other structural units (e) are structural units derived from monomers (me) (also referred to as monomers (me)) having other ethylenically unsaturated groups copolymerizable with monomers (ma), (m-pb), (mc) and (md). Specific examples include aromatic vinyl compounds, cyclic olefins having a norbornene structure, dienes, (meth)acrylates, (meth)acrylamide, vinyl compounds, unsaturated dicarboxylic acid diesters, monomaleimide, glycidyl (meth)acrylate, (meth)acrylamide, (meth)acrylonitrile, acrolein, and the like.

[0155] Examples of the aromatic vinyl compound include styrene, α-methylstyrene, o-vinyltoluene, p-vinyltoluene, o-chlorostyrene, m-chlorostyrene, methoxystyrene, p-nitrostyrene, p-cyanostyrene, and p-acetamidostyrene.

[0156] Examples of the cyclic olefin having a norbornene structure include norbornene (bicyclo[2.2.1]hept-2-ene), 5-methylbicyclo[2.2.1]hept-2-ene, tetracyclo[4.4.0.1 2,5 .1 7,10 ] dodec-3-ene, 8-ethyltetracyclo[4.4.0.1 2,5 .1 7,10 ] dodec-3-ene, dicyclopentadiene, tricyclo[5.2.1.0 2,6 ]dec-8-ene, tricyclo[4.4.0.1 2,5 ] undec-3-ene, tricyclo[6.2.1.0 1,8 ]Undec-9-ene, tetracyclo[4.4.0.1 2,5 .1 7,10 .0 1,6 ] dodec-3-ene, 8-ethylenetetracyclo[4.4.0.1 2,5 .1 7,12 ] dodec-3-ene, pentacyclic [6.5.1.1 3,6 .0 2,7 .0 9,13 ]pentadeca-4-ene, etc.

[0157] Examples of the diene include butadiene, isoprene, and chloroprene.

[0158] Examples of the (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, tert-butyl (meth)acrylate, amyl (meth)acrylate, benzyl (meth)acrylate, isoamyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, dodecyl (meth)acrylate, cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, rosin (meth)acrylate, norbornyl (meth)acrylate, 5-ethylnorbornyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl acrylate, isobornyl (meth)acrylate, Adamantyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 1,1,1-trifluoroethyl (meth)acrylate, perfluoroethyl (meth)acrylate, perfluoro-n-propyl (meth)acrylate, 3-(N,N-dimethylamino)propyl (meth)acrylate, triphenylmethyl (meth)acrylate, phenyl (meth)acrylate, isopropyl (meth)acrylate, 4-phenoxyphenyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, nonylphenoxypolyethylene glycol mono(meth)acrylate, biphenyloxyethyl (meth)acrylate, naphthyl (meth)acrylate, anthracene (meth)acrylate, ethoxylated phenyl (meth)acrylate, and the like.

[0159] Examples of the (meth)acrylamide include (meth)acrylamide, (meth)acrylic acid N,N-dimethyl(meth)acrylic acid amide, (meth)acrylic acid N,N-diisopropyl(meth)acrylic acid amide, and (meth)acrylic acid anthracenamide.

[0160] Examples of the vinyl compound include vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, N-vinyl pyrrolidone, vinyl pyridine, vinyl acetate, and vinyltoluene.

[0161] Examples of the unsaturated dicarboxylic acid diester include diethyl citraconic acid, diethyl maleate, diethyl fumarate, and diethyl itaconate.

[0162] Examples of the monomaleimide include N-phenylmaleimide, N-cyclohexylmaleimide, and N-laurylmaleimide.

[0163] Among them, from the viewpoint of availability and reactivity when synthesizing the copolymer (A), aromatic vinyl compounds, (meth)acrylates containing an aromatic group, and (meth)acrylate alkyl esters having an alkyl group with 1 to 12 carbon atoms are preferred; styrene, benzyl (meth)acrylate, dicyclopentyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and methyl (meth)acrylate are more preferred; and 2-ethylhexyl (meth)acrylate and methyl (meth)acrylate are more preferred.

[0164] The monomer (me) may be used alone or in combination of two or more.

[0165] If the copolymer (A) contains the structural unit (e), the content thereof is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, and even more preferably 5 to 40 mol% relative to all the structural units of the copolymer (A). By setting the content of the structural unit (e) to the above range, while fully ensuring the functions of the structural units (a) to (d), additional functions can be imparted by the structural unit (e), or the functions obtained by the structural units (a) to (d) can be adjusted within an appropriate range.

[0166] [Ethylenically Unsaturated Group Equivalent Weight of Copolymer (A)]

[0167] The ethylenically unsaturated group equivalent of copolymer (A) is preferably 300 g / mol or more, more preferably 500 g / mol or more, and more preferably 1000 g / mol or more. The ethylenically unsaturated group equivalent of copolymer (A) is preferably 8000 g / mol or less, more preferably 7000 g / mol or less, and more preferably 5000 g / mol or less. The combination of these lower limits and upper limits can be any combination. The ethylenically unsaturated group equivalent of copolymer (A) is preferably 300 to 8000 g / mol, more preferably 500 to 7000 g / mol, and more preferably 1000 to 5000 g / mol. When it is 300 g / mol or more, the storage stability as a photosensitive resin composition will be good. When it is 8000 g / mol or less, the solvent resistance of the cured product is good even when cured at low temperature.

[0168] The “ethylenically unsaturated group equivalent” indicates the mass of a polymer per 1 mol of ethylenically unsaturated groups in the polymer. The ethylenically unsaturated group equivalent (g / mol) of the copolymer (A) is obtained by dividing the mass of the copolymer (A) by the number of moles of the ethylenically unsaturated groups contained in the copolymer (A).

[0169] In this specification, R of formula (1-1) and formula (1-2) in the copolymer 2 and R 3When all of them are hydrogen atoms, the ethylenically unsaturated group equivalent is a value calculated from the conversion rate of the structural unit (pb) to the structural unit (b) calculated from the area ratio of the NMR spectrum obtained under the following conditions using an NMR apparatus (e.g., Bruker ULTRA SHIELD PLUS 400 (400 MHz), Bruker Corporation), and the feed amounts of the monomers (ma), (m-pb) and (mc) to (me) used when producing the resin precursor (PA) described later.

[0170] (NMR conditions)

[0171] Measurement method: 1 H-NMR

[0172] Lock solvent: CDCl3

[0173] Internal standard: TSP-d4 (sodium trimethylsilyl propionate) = 0 ppm

[0174] Temperature: Room temperature

[0175] Sample preparation: powder sample (20 mg) / CDCl3 (1 mL) + TSP-d4 (5 mg)

[0176] (Sample Preparation Method)

[0177] 20 mg of the dried copolymer was accurately weighed, and CDCl3 (1 mL) was added to a 20 mL sample bottle to dissolve it. After vibrating it with an ultrasonic cleaner for 5 minutes, it was sealed in a 5 mmφ NMR sample tube, and NMR measurement was performed immediately after sampling.

[0178] The conversion rate from the structural unit (pb) to the structural unit (b) is based on the -CR detected at 2.5 to 3.0 ppm. 2 -CHR 3 The spectrum of "-CH2-" of -C(=O)- (i.e., -CH-CH2-C(=O)-) is similar to the spectrum of -C(=O)-CR detected at 6.5-7.0 ppm. 3 =CR 2 -C(=O)- and -C(=O)-CR 2 =CR 3 The area ratio of the spectrum of -C(=O)- (ie, -C(=O)-CH=CH-C(=O)-) was calculated according to the following formula.

[0179] Conversion rate from structural unit (pb) to structural unit (b) = (-C(=O)-CH=CH-C(=O)-) / {(-CH-CH2-C(=O)-)+(-C(=O)-CH=CH-C(=O)-)}×100(%)

[0180] In the present specification, the copolymer comprises: a structural unit (b) having a group represented by formula (1-1) or formula (1-2), wherein R 2 and R 3 When at least one or both of is a hydrocarbon group having 1 to 20 carbon atoms, the ethylenically unsaturated group equivalent is a value calculated based on the amount of halogen bonded to the copolymer. The amount of halogen bonded to the copolymer is evaluated as follows in accordance with JIS K 0070:1992.

[0181] That is, the dried copolymer is dissolved in chloroform, and an appropriate amount of Wijs solution is added and stirred. Then, it is placed in a dark place at 23°C in a sealed state for 1 hour. Potassium iodide solution and water are added to the solution and stirred, and the resulting solution is titrated with sodium thiosulfate solution. When the solution turns slightly yellow, a few drops of starch solution are added and titrated until the blue color disappears. The ethylenically unsaturated bonds in the copolymer react with the halogen molecules in a 1:1 ratio. Therefore, the ethylenically unsaturated group equivalent of the copolymer is obtained by dividing the mass (g) of the copolymer used for the measurement by the mass (mol) of the halogen molecules bonded to the copolymer obtained by the measurement.

[0182] [Acid value of copolymer (A)]

[0183] The acid value of the copolymer (A) is preferably 10KOHmg / g or more, more preferably 15KOHmg / g or more, and more preferably 20KOHmg / g or more. The acid value of the copolymer (A) is preferably 300KOHmg / g or less, more preferably 200KOHmg / g or less, and more preferably 150KOHmg / g or less. The combination of these lower limits and upper limits may be any combination. The acid value of the copolymer (A) is preferably 10 to 300KOHmg / g, more preferably 15 to 200KOHmg / g, and more preferably 20 to 150KOHmg / g. When it is 10KOHmg / g or more, the developability is good. When it is 300KOHmg / g or less, the storage stability is good.

[0184] The "acid value" refers to the acid value of the curable polymer measured in accordance with JIS K6901: 2008 5.3. That is, the acid value means the number of mg of potassium hydroxide required to neutralize the acidic components contained in 1 g of the copolymer.

[0185] [Weight Average Molecular Weight of Copolymer (A)]

[0186] The weight average molecular weight of the copolymer (A) is preferably 1000 or more, more preferably 3000 or more, and more preferably 5000 or more. The weight average molecular weight of the copolymer (A) is preferably 50000 or less, more preferably 40000 or less, and more preferably 30000 or less. The combination of these lower limits and upper limits may be any combination. The weight average molecular weight of the copolymer (A) is preferably 1000 to 50000, more preferably 3000 to 40000, and more preferably 5000 to 30000. When it is 1000 or more, when the copolymer (A) is used as a raw material for a photosensitive resin composition, the cured resin film after development is not prone to defects such as defects. When it is 50000 or less, the photosensitive resin composition containing the copolymer (A) will become a resin composition having a sufficiently short development time and excellent practicality.

[0187] In this specification, the weight average molecular weight means the standard polystyrene conversion weight average molecular weight measured according to the following conditions using gel permeation chromatography (GPC).

[0188] Column: Two Shodex (trademark) LF-804 (manufactured by Showa Denko K.K.) were connected in series.

[0189] Column temperature: 40℃

[0190] Sample: 0.2 mass % tetrahydrofuran solution of the object to be measured

[0191] Developing solvent: tetrahydrofuran

[0192] Detector: Differential refractometer (Shodex (trademark) RI-71S) (manufactured by Showa Denko K.K.)

[0193] Flow rate: 1mL / min

[0194] [Blocked isocyanate group equivalent weight of copolymer (A)]

[0195] The blocked isocyanate group equivalent of the copolymer (A) is preferably 100 to 2000 g / mol, more preferably 200 to 1500 g / mol, and more preferably 300 to 1300 g / mol. When it is 100 g / mol or more, the photosensitive resin composition containing the copolymer (A) has better developability. When it is 2000 g / mol or less, the photosensitive resin composition containing the copolymer (A) can form a resin cured film with better hardness.

[0196] "Blocked isocyanate group equivalent" means the mass of the polymer per 1 mol of blocked isocyanate groups in the polymer. The blocked isocyanate group equivalent (g / mol) of the copolymer is obtained by dividing the mass of the copolymer by the number of moles of blocked isocyanate groups contained in the copolymer. In this specification, "blocked isocyanate group equivalent" is a theoretical value calculated based on the feed amount of the monomer used when manufacturing the copolymer.

[0197] [Hydroxyl equivalent of copolymer (A)]

[0198] The hydroxyl equivalent of the copolymer (A) is preferably 200 to 5000 g / mol, more preferably 400 to 4000 g / mol, and more preferably 800 to 3000 g / mol. When it is 200 g / mol or more, the photosensitive resin composition containing the copolymer (A) has better developability. When it is 5000 g / mol or less, the photosensitive resin composition containing the copolymer (A) can form a resin cured film with better hardness.

[0199] "Hydroxy equivalent" means the mass of a polymer per 1 mol of hydroxyl groups in a polymer. The hydroxyl equivalent (g / mol) of a copolymer is obtained by dividing the mass of the copolymer by the number of moles of hydroxyl groups contained in the copolymer. In this specification, "hydroxyl equivalent" is a theoretical value calculated based on the feed amount of the monomer used when manufacturing the copolymer.

[0200] [Method for producing copolymer (A)]

[0201] (Method for producing resin precursor (PA))

[0202] The resin precursor (PA) can be produced by copolymerizing monomers (ma) and (m-pb) corresponding to the structural units (a) and (pb) respectively contained in the resin precursor (PA). The ratio of the structural units (a) and (pb) contained in the resin precursor (PA) is the same as the ratio of each monomer (ma) and (m-pb) in the total of all monomers used as raw materials of the resin precursor (PA) (hereinafter sometimes referred to as "raw material monomers").

[0203] Therefore, the ratio of each monomer (ma) and (m-pb) in the raw material monomer used as the raw material of the resin precursor (PA) is preferably (ma) 5 to 50 mol% and (m-pb) 3 to 40 mol%, more preferably (ma) 8 to 40 mol% and (m-pb) 5 to 35 mol%, and more preferably (ma) 10 to 30 mol% and (m-pb) 10 to 30 mol%.

[0204] When a substance containing the structural unit (c) is produced as a resin precursor (PA), as a raw material monomer of the resin precursor (PA), in addition to the monomers (ma) and (m-pb), a monomer (mc) may be further used. In this case, the proportion of the monomer (mc) in the raw material monomer used as a raw material of the resin precursor (PA) is preferably 3 to 40 mol%, more preferably 5 to 30 mol%, and even more preferably 8 to 25 mol%.

[0205] When manufacturing a resin precursor (PA) containing the structural unit (d), as a raw material monomer of the resin precursor (PA), in addition to the monomers (ma) and (m-pb), a monomer (md) can be used. In this case, the ratio of the monomer (md) in the raw material monomer used as a raw material of the resin precursor (PA) is preferably 5 to 45 mol%, more preferably 10 to 40 mol%, and more preferably 15 to 35 mol%.

[0206] When producing a resin precursor (PA) containing the structural unit (e), as a raw material monomer of the resin precursor (PA), in addition to the monomers (ma) and (m-pb), a monomer (me) may be further used. In this case, the ratio of the monomer (me) in the raw material monomer used as a raw material of the resin precursor (PA) is preferably 1 to 50 mol%, more preferably 3 to 45 mol%, and even more preferably 5 to 40 mol%.

[0207] The copolymerization reaction of the raw material monomers (monomers (ma) and (m-pb), and monomers (mc), (md) and (me) used as needed) for producing the resin precursor (PA) can be carried out in the presence or absence of a polymerization solvent according to a free radical polymerization method known in the art. Specifically, for example, a method can be used in which the raw material monomers, a polymerization initiator and a polymerization solvent are mixed as a raw material monomer solution and the polymerization reaction is carried out at a temperature of 50 to 100° C. for 1 to 20 hours under a nitrogen atmosphere.

[0208] As the polymerization solvent used in producing the resin precursor (PA), any solvent that can be used in the solvent (PD) described later can be used alone or in combination of two or more.

[0209] When the raw material monomers include monomers (mc) and (md), the temperature at which the raw material monomers are subjected to copolymerization reaction is preferably lower than the following temperature: "the temperature at which the dissociation rate of the blocked isocyanate group in the monomer (md) having a blocked isocyanate group and an ethylenically unsaturated bond within 30 minutes is 80% or more". This is to inhibit the blocked isocyanate group in the monomer (md) from dissociating in the raw material monomer solution to produce an isocyanate group during the copolymerization reaction, and reacting with the hydroxyl group in the hydroxyl-containing monomer (mc) to form a gel. The temperature at which the raw material monomers are subjected to copolymerization reaction is further preferably 20 to 50°C lower than the following temperature: "the temperature at which the dissociation rate of the blocked isocyanate group in the monomer (md) within 30 minutes is 80% or more".

[0210] Specifically, the temperature for copolymerizing the raw material monomers can be set to 50 to 100°C, preferably 60 to 90°C, and more preferably 65 to 85°C.

[0211] As the polymerization initiator used to make the raw material monomer copolymerize, for example, 2,2'-azobis(2,4-dimethylvaleronitrile), azobisisobutyronitrile, azobisisovaleronitrile, benzoyl peroxide, tert-butylperoxy-2-ethylhexanoate, etc. can be listed. The polymerization initiator can be used alone or in combination of two or more. The amount of the polymerization initiator used can be set to 0.5 to 20 parts by mass, preferably 1.0 to 16 parts by mass, relative to 100 parts by mass of the raw material monomer (the total feed amount of the monomer).

[0212] When producing the resin precursor (PA), additives such as a polymerization inhibitor, a chain transfer agent, a photosensitizer, a filler, and a plasticizer may be used as necessary within a range not impairing the effects of the present invention.

[0213] (Reaction from Resin Precursor (PA) to Copolymer (A))

[0214] The copolymer (A) can be produced by converting the structural unit (pb) contained in the resin precursor (PA) into the structural unit (b) in the presence of a basic catalyst and a solvent (PD). For example, a resin precursor composition containing a resin precursor (PA), a basic catalyst and a solvent (PD) is maintained at a temperature of 0 to 150° C. for 0.1 to 10 hours. In this way, the structural unit (pb) contained in the resin precursor (PA) is converted into the structural unit (b) by a dealcoholization reaction and a decarboxylation reaction of the resin precursor (PA), thereby generating a reaction solution containing a copolymer (A) and a solvent (PD).

[0215] [Basic catalyst]

[0216] The basic catalyst can be any one of the groups represented by the formula (1) in the structural unit (pb) contained in the resin precursor (PA) and in R 2 The carbon atom bonded to R 3 There is no particular limitation as long as the carbon atoms to be bonded can form a double bond. The basic catalyst may be used alone or in combination of two or more.

[0217] As the basic catalyst, it is preferred to use a basic catalyst having a pKa (acidity constant) of 12.5 or more at 25°C. The basic catalyst having a pKa of 12.5 or more at 25°C includes a basic catalyst having a pKa of 12.5 or more in an aqueous solution and a basic catalyst having a pKa of 12.5 or more in an aqueous solution that is too acidic to be measured in an aqueous solution but is converted from the measurement results in an organic solvent.

[0218] The basic catalyst is preferably a compound represented by the following formula (6).

[0219] R 11 N=CR 12 —NR 13 R 14 …(6)

[0220] (In formula (6), R 11 , R 13 and R 14 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 12 is a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or -N(R 15 )2 represents a group (in the formula R 15 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and two R 15 may be the same or different from each other), R 11 , R 12 , R 13 , R 14 and 2 R 15 Any two or more groups in can be bonded to form a ring structure)

[0221] The basic catalyst may be a compound represented by formula (7).

[0222] R 16 N=CR 17 -NR 18 R 19 …(7)

[0223] (In formula (7), R 16 , R 17 , R 18 and R 19 is a hydrocarbon group, R 16 With R19 The bonds form a ring structure, and R 16 With R 19 The total number of carbon atoms is 3 to 20, R 17 With R 18 The bonds form a ring structure, and R 17 With R 18 The total number of carbon atoms is 3 to 20)

[0224] In the compound represented by formula (7), R forming a ring structure 16 With R 19 The total number of carbon atoms is 3 to 20, preferably 3 to 10 from the viewpoint of easy availability.

[0225] In the compound represented by formula (7), R forming a ring structure 17 With R 18 The total number of carbon atoms is 3 to 20, preferably 3 to 10 from the viewpoint of easy availability.

[0226] Specifically, as the basic catalyst, it is preferred to use one or more selected from 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) (pKa 12.5), 1,5-diazabicyclo[4.3.0]-5-nonene (pKa 12.7) and 1,1,3,3-tetramethylguanidine (pKa 13.6). In particular, from the viewpoint of the intensity of the catalytic activity, the compatibility with the solvent, the availability, etc., it is preferred to use 1,8-diazabicyclo[5.4.0]-7-undecene.

[0227] The content of the basic catalyst is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and more preferably 0.1 to 3 parts by mass relative to 100 parts by mass of the resin precursor (PA). When the content of the basic catalyst is 0.01 parts by mass or more, it is preferred because the reaction rate of converting the structural unit (pb) contained in the resin precursor (PA) into the structural unit (b) is sufficiently fast. When the content of the basic catalyst is 10 parts by mass or less, the influence of the basic catalyst during curing of the photosensitive resin composition containing the copolymer (A) manufactured using the resin precursor composition can be suppressed.

[0228] [Solvent (PD)]

[0229] Examples of the solvent (PD) include (poly) alkylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, and 3-methoxy-1-butanol; hydroxyl-containing carboxylates such as methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxypropionate, ethyl hydroxyacetate, and methyl 2-hydroxy-3-methylbutyrate; and hydroxyl-containing solvents such as diethylene glycol; and (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; Ethers such as alcohol 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; esters such as methyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl ethoxyacetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutyl propionate, ethyl acetate, n-butyl acetate, isopropyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, isopropyl butyrate, ethyl pyruvate, n-propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, and ethyl 2-oxobutyrate; aromatic hydrocarbons such as toluene and xylene; and solvents not containing hydroxyl groups such as carboxylic acid amides such as N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide. The solvent (PD) may be used alone or in combination of two or more.

[0230] Among these solvents (PD), ethers are preferably used from the viewpoint of availability, cost, and stability during resist preparation. Specifically, one or more selected from propylene glycol monomethyl ether acetate, diethylene glycol methyl ethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, and 3-methoxy-1-butanol are more preferably used.

[0231] The content of the solvent (PD) is preferably 30 to 1,000 parts by mass, and more preferably 50 to 800 parts by mass, relative to 100 parts by mass of the total of the components other than the solvent (PD) contained in the resin precursor composition. When the content of the solvent (PD) is 30 parts by mass or more, a stable polymerization reaction can be performed, so it is preferred. When the content of the solvent (PD) is 1,000 parts by mass or less, the viscosity of the resin precursor composition can be appropriately adjusted, so it is preferred.

[0232] When the resin precursor (PA) contains structural units (c) and (d), the conversion reaction of converting the structural unit (pb) into the structural unit (b) is preferably carried out at a temperature condition lower than the following temperature: "the temperature at which the dissociation rate of the blocked isocyanate group in the structural unit (d) having a blocked isocyanate group within 30 minutes is 80% or more". This is to inhibit the blocked isocyanate group in the structural unit (d) from dissociating to produce an isocyanate group in the resin precursor composition during the conversion reaction, and reacting with the hydroxyl group in the structural unit (c) having a hydroxyl group to form a gel. The temperature condition for carrying out the above-mentioned conversion reaction is further preferably 20 to 50°C lower than the following temperature: "the temperature at which the dissociation rate of the blocked isocyanate group in the structural unit (d) within 30 minutes is 80% or more".

[0233] Specifically, the temperature of the conversion reaction of converting the structural unit (pb) into the structural unit (b) can be set to 0 to 150°C, preferably 50 to 120°C, and more preferably 60 to 100°C.

[0234] In order to carry out the above conversion reaction, the holding time of the resin precursor composition under the above temperature conditions can be set to 0.1 to 10 hours, preferably 0.3 to 5 hours, and more preferably 0.5 to 3 hours. The holding time can be appropriately determined according to the content of the structural unit (pb) contained in the resin precursor (PA) in the resin precursor composition, the content of the basic catalyst, the temperature conditions, etc.

[0235] The environment in the reaction container in which the above conversion reaction is performed can be an environment containing, for example, air, dry air, nitrogen, helium, etc., and is preferably a dry air or nitrogen environment.

[0236] The pressure in the reaction vessel in which the above conversion reaction is performed is not particularly limited, but is preferably normal pressure.

[0237] (Reaction Path)

[0238] In the conversion reaction from the resin precursor (PA) to the copolymer (A), it is estimated that the structural unit (pb) contained in the resin precursor (PA) is converted into the structural unit (b) through the reaction pathway shown below.

[0239]

[0240] That is, in the structural unit (pb) having a group represented by the formula (1) contained in the resin precursor (PA), the H of -NH- in the carbamate group and the ester part (-COOR 1 or -COOR 4 ) between the two.

[0241] In this way, a group having a heterocyclic ring represented by formula (1-3) and / or formula (1-4) is formed. 4 The dealcoholization reaction of the ester part (-R 4 OH) to form a group having a heterocyclic ring represented by formula (1-3). 1 The dealcoholization reaction of the ester part (-R 1 OH) to form a group having a heterocyclic ring represented by formula (1-4).

[0242]

[0243] (In formula (1-3), R 1 , R 2 and R 3 With R in formula (1) 1 , R 2 and R 3 The same as above, * indicates the site connected to the residue after removing the group of formula (1-3) from the structural unit (pb)

[0244]

[0245] (In formula (1-4), R 2 , R 3 and R 4 With R in formula (1) 2 , R 3 and R 4 The same as above, * indicates the site connected to the residue after removing the group of formula (1-4) from the structural unit (pb)

[0246] Next, in the group having a heterocyclic ring represented by the above formula (1-3), decarboxylation (-CO2) occurs in the heterocyclic ring portion. In this way, the group having a heterocyclic ring represented by the formula (1-3) is converted into a group represented by the following formula (1-1).

[0247]

[0248] (In formula (1-1), R 1 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and * represents a site connected to the residue after removing the group of formula (1-1) from the structural unit (b)

[0249] On the other hand, in the group having a heterocyclic ring represented by the above formula (1-4), decarboxylation (-CO2) occurs in the heterocyclic ring portion. Thus, the group having a heterocyclic ring represented by the formula (1-4) is converted into a group represented by the following formula (1-2).

[0250]

[0251] (In formula (1-2), R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 4 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and * represents a site connected to the residue after removing the group of formula (1-2) from the structural unit (b)

[0252] In the density functional method, wB97XD was used as a functional function and 6-31+g(d) was used as a basis function to calculate the transition state of each product in the generation path. As a result, in the conversion reaction of converting the above-mentioned structural unit (pb) into the structural unit (b), the activation barrier of the reaction paths of formula (1), formula (1-4) and formula (1-2) was lower than that of the reaction paths of formula (1), formula (1-3) and formula (1-1), so it was speculated that they were the main conversion paths. Therefore, it was speculated that the structural unit having the group represented by formula (1-2) and the structural unit having the group represented by formula (1-1) were mixed in the copolymer (A), and the amount of the structural unit having the group represented by formula (1-2) was greater than that of the structural unit having the group represented by formula (1-1).

[0253] <Photosensitive resin composition and photosensitive coloring composition>

[0254] The photosensitive resin composition of one embodiment contains a copolymer (A), a reactive diluent (B), a photopolymerization initiator (C), and a solvent (D). The photosensitive coloring composition of one embodiment further contains a coloring agent (E).

[0255] The content of the copolymer (A) in the photosensitive resin composition or the photosensitive coloring composition is preferably 10 parts by mass or more, more preferably 30 parts by mass or more, and more preferably 60 parts by mass or more, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). The content of the copolymer (A) in the photosensitive resin composition or the photosensitive coloring composition is preferably 90 parts by mass or less, more preferably 85 parts by mass or less, and more preferably 80 parts by mass or less, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). Any combination of these lower limits and upper limits may be used. The content of the copolymer (A) in the photosensitive resin composition or the photosensitive coloring composition is preferably 10 to 90 parts by mass, more preferably 30 to 85 parts by mass, and more preferably 60 to 80 parts by mass, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). When the content of the copolymer (A) is 10 parts by mass or more, a photosensitive resin composition or a photosensitive coloring composition having more excellent low temperature curability and capable of forming a cured product having good solvent resistance can be obtained. When the content of the copolymer (A) is 90 parts by mass or less, the content of the reactive diluent (B) can be sufficiently ensured, so that the strength of the cured product and the adhesion to the substrate are good.

[0256] [Reactive diluent (B)]

[0257] The reactive diluent (B) is a monomer having at least one ethylenically unsaturated bond as a polymerizable functional group in the molecule. The reactive diluent (B) may be a monofunctional monomer or a polyfunctional monomer having a plurality of polymerizable functional groups. By containing the reactive diluent (B), the viscosity of the photosensitive resin composition or the photosensitive coloring composition can be set to an appropriate range according to the application. In addition, since the photosensitive resin composition or the photosensitive coloring composition contains the reactive diluent (B), it has good photocurability and can form a cured product with good strength and adhesion to the substrate. The reactive diluent (B) can be used alone or in combination of two or more.

[0258] Examples of the monofunctional monomer used as the reactive diluent (B) include (meth)acrylamide, hydroxymethyl (meth)acrylamide, methoxymethyl (meth)acrylamide, ethoxymethyl (meth)acrylamide, propoxymethyl (meth)acrylamide, butoxymethoxymethyl (meth)acrylamide, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 2-hydroxyethyl (meth)acrylate. (Meth)acrylates such as 2-phenoxy-2-hydroxypropyl ester, 2-(meth)acryloyloxy-2-hydroxypropyl phthalate, glycerol mono(meth)acrylate, tetrahydrofurfuryl(meth)acrylate, glycidyl(meth)acrylate, 2,2,2-trifluoroethyl(meth)acrylate, 2,2,3,3-tetrafluoropropyl(meth)acrylate, and (meth)acrylate half esters of phthalic acid derivatives; aromatic vinyl compounds such as styrene, α-methylstyrene, α-chloromethylstyrene, and vinyltoluene; carboxylic acid esters such as vinyl acetate and vinyl propionate, etc. The monofunctional monomers may be used alone or in combination of two or more.

[0259] Examples of the polyfunctional monomer used as the reactive diluent (B) include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, glycerol di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypolyethoxyphenyl)propane, 2-hydroxy-3-(meth)acryloyloxy (Meth)acrylates such as propyl (meth)acrylate, ethylene glycol diglycidyl ether di(meth)acrylate, diethylene glycol diglycidyl ether di(meth)acrylate, diglycidyl phthalate di(meth)acrylate, glycerol triacrylate, glycerol polyglycidyl ether poly(meth)acrylate, urethane (meth)acrylate (for example, a reaction product of toluene diisocyanate, trimethylhexamethylene diisocyanate, hexamethylene diisocyanate, etc. and 2-hydroxyethyl (meth)acrylate), tri(meth)acrylate of tri(hydroxyethyl)isocyanate, etc.; aromatic vinyl compounds such as divinylbenzene, diallyl phthalate, diallyl phenylphosphonate, etc.; dicarboxylic acid esters such as divinyl adipate, triallyl cyanurate, methylenebis(meth)acrylamide, and a condensate of a polyol and N-methylol (meth)acrylamide, etc. The multifunctional monomer may be used alone or in combination of two or more.

[0260] Among these monomers, it is preferred to use a polyfunctional (meth)acrylate as the reactive diluent (B) because a photosensitive resin composition or a photosensitive coloring composition having good photocurability can be formed. It is further preferred to use a trifunctional or higher polyfunctional (meth)acrylate, and it is more preferred to use trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, or dipentaerythritol hexa(meth)acrylate.

[0261] The content of the reactive diluent (B) in the photosensitive resin composition or the photosensitive coloring composition is preferably 10 parts by mass or more, more preferably 15 parts by mass or more, and more preferably 30 parts by mass or more, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). The content of the reactive diluent (B) in the photosensitive resin composition or the photosensitive coloring composition is preferably 90 parts by mass or less, more preferably 70 parts by mass or less, and more preferably 60 parts by mass or less, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). Any combination of these lower limits and upper limits may be used. The content of the reactive diluent (B) in the photosensitive resin composition or the photosensitive coloring composition is preferably 10 to 90 parts by mass, more preferably 15 to 70 parts by mass, and more preferably 30 to 60 parts by mass, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). When the content of the reactive diluent (B) is 10 parts by mass or more, the effect of containing the reactive diluent (B) becomes significant. When the content of the reactive diluent (B) is 90 parts by mass or less, since the content of the copolymer (A) can be sufficiently ensured, a photosensitive resin composition or a photosensitive coloring composition with better low-temperature curing properties can be formed.

[0262] [Photopolymerization initiator (C)]

[0263] The photopolymerization initiator (C) is not particularly limited, and examples thereof include 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-,-1-(O-acetoxime); benzoin and its alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin butyl ether; acetophenone compounds such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, and 4'-(1-tert-butyldioxy-1-methylethyl)acetophenone; 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propane-1-one; 2-benzyl-2 -dimethylamino-1-(4-morpholinophenyl)butanone-1; anthraquinone compounds such as 2-methylanthraquinone, 2-amylanthraquinone, 2-tert-butylanthraquinone, and 1-chloroanthraquinone; xanthone; thioxanthone compounds such as 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorothioxanthone; ketal compounds such as acetophenone dimethyl ketal and benzyl dimethyl ketal; diphenyl ketone compounds such as diphenyl ketone, 4-(1-tert-butyldioxy-1-methylethyl)diphenyl ketone, and 3,3',4,4'-tetrakis(tert-butyldioxycarbonyl)diphenyl ketone; acylphosphine oxide-based photopolymerization initiators, etc. The photopolymerization initiator (C) may be used alone or in combination of two or more.

[0264] The content of the photopolymerization initiator (C) in the photosensitive resin composition or the photosensitive coloring composition is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). The content of the photopolymerization initiator (C) in the photosensitive resin composition or the photosensitive coloring composition is preferably 30 parts by mass or less, more preferably 15 parts by mass or less, and more preferably 10 parts by mass or less, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). Any combination of these lower limits and upper limits may be used. The content of the photopolymerization initiator (C) in the photosensitive resin composition or the photosensitive coloring composition is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 15 parts by mass, and more preferably 1 to 10 parts by mass, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). When the content of the photopolymerization initiator (C) is 0.1 parts by mass or more, a photosensitive resin composition or a photosensitive coloring composition having good photocurability can be formed. When the content of the photopolymerization initiator (C) is 30 parts by mass or less, it is possible to prevent the physical properties of the cured product of the photosensitive resin composition or the photosensitive coloring composition from being adversely affected by excessive amounts of the photopolymerization initiator (C).

[0265] [Solvent (D)]

[0266] As the solvent (D), the same solvent (PD) as that used in the production of the copolymer (A) can be used. The solvent (D) in the photosensitive resin composition or the photosensitive coloring composition may be the same as or different from the solvent (PD) used in the production of the copolymer (A).

[0267] The content of the solvent (D) in the photosensitive resin composition or the photosensitive coloring composition is preferably 30 parts by mass or more, and more preferably 50 parts by mass or more, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). The content of the solvent (D) in the photosensitive resin composition or the photosensitive coloring composition is preferably 1,000 parts by mass or less, and more preferably 800 parts by mass or less, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). Any combination of these lower limits and upper limits may be used. The content of the solvent (D) in the photosensitive resin composition or the photosensitive coloring composition is preferably 30 to 1,000 parts by mass, and more preferably 50 to 800 parts by mass, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). When the content of the solvent (D) is 30 parts by mass or more, the viscosity of the photosensitive resin composition or the photosensitive coloring composition can be set to an appropriate range. When the content of the solvent (D) is 1,000 parts by mass or less, the solvent (D) can be easily removed when removing the solvent (D) in a coating film formed by applying the photosensitive resin composition or the photosensitive coloring composition on a substrate.

[0268] [Colorant (E)]

[0269] The photosensitive coloring composition may further contain a colorant (E). The photosensitive coloring composition containing a colorant (E) can be used as a material for a color filter.

[0270] The colorant (E) is not particularly limited as long as it can be dissolved or dispersed in the solvent (D), and examples thereof include dyes and pigments.

[0271] From the viewpoints of solubility in the solvent (D) and the alkali developer, interaction with other components in the photosensitive coloring composition, heat resistance, etc., it is preferred to use an acid dye having an acid group such as a carboxyl group or a sulfone group, a salt of an acid dye with a nitrogen compound, a sulfonamide adduct of an acid dye, and the like as the dye.

[0272] 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; solvent blue 38, 44, 70; 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 red red)1,4,8,14,17,18,26,27,29,31,34,35,37,42,44,50,51,52,57,69,73,80,87,88,91,92,94,97,103,111,114,129,133,134,138,143,145,150,151,158,176,183,198,211,215,216,217,249,252,257,260,266,274; acid violet (acid violet)6B,7,9,17,19; acid yellow (acid Yellow) 1, 3, 9, 11, 17, 23, 25, 29, 34, 36, 42, 54, 72, 73, 76, 79, 98, 99, 111, 112, 114, 116; food yellow 3 and their derivatives, etc. Among these, azo, xanthene, anthraquinone, or phthalocyanine acid dyes are preferred. The dyes can be used alone or in combination of two or more.

[0273] 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, 214, etc.; orange pigments such as CI Pigment Orange 13, 31, 36, 38, 40, 42, 43, 51, 55, 59, 61, 64, 65, 71, 73, etc.; CI Pigment Red 9, 97, 105, 118, 126, 127, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 147, 148, 150, 22, 123, 144, 149, 166, 168, 176, 177, 180, 192, 209, 215, 216, 224, 242, 254, 255, 264, 265 and the like red pigments; CI pigment blue 15, 15:3, 15:4, 15:6, 60 and the like blue pigments; CI pigment violet 1, 19, 23, 29, 32, 36, 38 and the like purple pigments; CI pigment green 7, 36, 58, 59 and the like green pigments; CI pigment brown 23, 25 and the like brown pigments; CI pigment black 1, 7, carbon black, titanium black, iron oxide and the like black pigments, etc. The pigments may be used alone or in combination of two or more.

[0274] The colorant (E) can be appropriately determined according to the color of the target coloring pattern (black matrix and pixel), for example. The colorant (E) can be used alone or in combination of two or more. When two or more colorants are used as the colorant (E), a dye and a pigment can also be used in combination.

[0275] When a pigment is used as a colorant (E), a known dispersant may be formulated in the photosensitive coloring composition from the viewpoint of improving the dispersibility of the pigment. As a dispersant, a polymer dispersant having excellent dispersion stability over time is preferably used. As a polymer dispersant, for example, urethane dispersants, polyethyleneimine dispersants, polyoxyethylene alkyl ether dispersants, polyoxyethylene glycol diester dispersants, sorbitan aliphatic ester dispersants, aliphatic modified ester dispersants, etc. may be cited. As a polymer dispersant, commercial products under the trade names of EFKA (manufactured by EFKA CHEMICALS BV), Disperbyk (manufactured by BYK), DISPARLON (manufactured by Kusumoto Chemicals Co., Ltd.), SOLSPERSE (manufactured by Lubrizol) and the like may be used. The content of the dispersant may be appropriately set according to the type and amount of the pigment used as the colorant (E).

[0276] The content of the colorant (E) in the photosensitive coloring composition is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, and more preferably 10 parts by mass or more, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). The content of the colorant (E) in the photosensitive coloring composition is preferably 80 parts by mass or less, more preferably 70 parts by mass or less, and more preferably 60 parts by mass or less, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). Any combination of these lower limits and upper limits may be used. The content of the colorant (E) in the photosensitive coloring composition is preferably 3 to 80 parts by mass, more preferably 5 to 70 parts by mass, and more preferably 10 to 60 parts by mass, relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B). When the content of the colorant (E) is 3 parts by mass or more, the effect of containing the colorant (E) becomes significant, so a photosensitive coloring composition suitable as a material for a coloring pattern of a color filter can be formed. When the content of the colorant (E) is 80 parts by mass or less, the colorant (E) does not affect the curability of the photosensitive coloring composition, and a photosensitive coloring composition having excellent low-temperature curability can be obtained.

[0277] [Other ingredients]

[0278] In the resin composition of one embodiment, in addition to the copolymer (A), the solvent (D), the reactive diluent (B), the photopolymerization initiator (C) and the colorant (E) contained as required, known additives such as a cross-linking agent, a leveling agent, and a thermal polymerization inhibitor may be added as required. The amount of the additives is not particularly limited as long as it is within the range that does not hinder the effect of the present invention.

[0279] <Method for producing photosensitive resin composition and photosensitive coloring composition>

[0280] The photosensitive resin composition of one embodiment can be produced by mixing the copolymer (A), the reactive diluent (B), the photopolymerization initiator (C) and the solvent (D) using a known mixing device. The photosensitive coloring composition of one embodiment can be produced by mixing the copolymer (A), the reactive diluent (B), the photopolymerization initiator (C), the solvent (D) and the colorant (E) using a known mixing device.

[0281] When producing a photosensitive resin composition or a photosensitive coloring composition, a reaction liquid containing a copolymer (A) obtained by converting the structural unit (pb) into the structural unit (b) in the resin precursor composition and a solvent (PD) can be used directly as a raw material. In this case, the solvent (PD) contained in the reaction liquid can be used as part or all of the solvent (D) contained in the photosensitive resin composition or the photosensitive coloring composition.

[0282] When producing the photosensitive resin composition or the photosensitive coloring composition, the copolymer (A) isolated from the reaction liquid containing the above-mentioned copolymer (A) and the solvent (PD) by a known method can be used as a raw material.

[0283] Since the photosensitive resin composition or the photosensitive coloring composition contains: a copolymer (A) having a structural unit (b) (which has a group represented by formula (1-1) or formula (1-2)), a reactive diluent (B) and a photopolymerization initiator (C), when irradiated with light, the reactive diluent (B) is polymerized together with the ethylenically unsaturated group contained in the structural unit (b) of the copolymer (A), thereby exhibiting good photocurability.

[0284] Furthermore, when the copolymer (A) contained in the photosensitive resin composition or the photosensitive coloring composition has a structural unit (c) having a hydroxyl group and a structural unit (d) having a blocked isocyanate group, it has more favorable low-temperature curability.

[0285] Therefore, when a photosensitive resin composition or a photosensitive coloring composition is used to form a cured product, it can be cured at a lower temperature than when a conventional resin composition is used. Therefore, when a photosensitive resin composition or a photosensitive coloring composition is subjected to a baking treatment after, for example, a coating film formed on a substrate is exposed, the crosslinking reaction can be sufficiently carried out even at a lower baking temperature, so that a cured product having excellent solvent resistance can be formed.

[0286] Therefore, when a photosensitive resin composition or a photosensitive coloring composition is used to form a cured product, the energy required for heating for curing is small. In addition, by using a photosensitive resin composition or a photosensitive coloring composition, a cured product can be formed on a substrate with low heat resistance such as a resin substrate without affecting the substrate. Furthermore, for a photosensitive coloring composition, even when a colorant with low heat resistance is used as a colorant (E), a cured product that can exert the original characteristics of the colorant (E) can be formed.

[0287] Even if the temperature of the baking treatment is lowered, the photosensitive coloring composition can form a cured product having excellent solvent resistance, so the colorant (E) is not easily eluted. Therefore, the content of the colorant (E) in the photosensitive coloring composition can be increased. The photosensitive coloring composition having a large content of the colorant (E) can be used as a material for a color pattern of a color filter, for example, to form a color filter having excellent color reproducibility.

[0288] Since the copolymer (A) contained in the photosensitive resin composition or the photosensitive coloring composition has "acid group-containing structural unit (a)", the photosensitive resin composition or the photosensitive coloring composition has good alkali developability. Since such a photosensitive resin composition or a photosensitive coloring composition has excellent alkali developability, for example, by coating it on a substrate to form a coating film, exposing it through a photomask corresponding to a predetermined pattern shape, and developing the unexposed portion with an alkaline aqueous solution, and then baking it at a sufficiently low temperature, a cured product having a predetermined pattern shape and excellent solvent resistance can be formed.

[0289] The photosensitive resin composition and the photosensitive coloring composition can be suitably used as a material for a color filter.

[0290] Under these circumstances, photosensitive resin compositions and photosensitive coloring compositions are very useful as materials for forming components of image display elements such as color filter pixels, black matrices, color filter protective films, photosensitive spacers, liquid crystal alignment projections, microlenses, and touch panel insulating films.

[0291] <Resin Cured Film>

[0292] The cured resin film according to one embodiment is composed of a cured product of a photosensitive resin composition or a photosensitive coloring composition.

[0293] The cured resin film can be produced by, for example, applying a photosensitive resin composition or a photosensitive coloring composition on a substrate, volatilizing the solvent (D) to form a coating film, exposing the coating film to light cure, and then baking the coating film.

[0294] When forming a resin cured film having a specified pattern shape, for example, the following method can be used. That is, a photosensitive resin composition or a photosensitive coloring composition is applied to a substrate, and the solvent (D) is volatilized and removed to form a coating film. Next, the coating film is exposed through a photomask having a specified pattern shape to photocure the exposed portion. Next, the unexposed portion of the coating film is developed with an alkaline aqueous solution. Then, the developed coating film is baked to form a resin cured film having a specified pattern shape.

[0295] As a method for coating the photosensitive resin composition or the photosensitive coloring composition, and a method for exposing and developing the coated film when producing a cured resin film, known methods can be used.

[0296] The conditions of the baking treatment performed when manufacturing the cured resin film can be appropriately determined according to the composition of the photosensitive resin composition or the photosensitive coloring composition, the film thickness of the coating film, the material of the substrate, etc. The baking treatment can be performed at a temperature of 70°C to 250°C, for example. When the temperature of the baking treatment is 70°C or above, the blocked isocyanate group possessed by the structural unit (d) having a blocked isocyanate group contained in the copolymer (A) in the photosensitive resin composition or the photosensitive coloring composition is fully dissociated. In this way, an isocyanate group is generated and undergoes a cross-linking reaction with the hydroxyl group possessed by the structural unit (c) having a hydroxyl group. When the structural unit (d) has a carboxylic acid alkyl ester structure, cross-linking formation is caused by the ester exchange of the carboxylic acid alkyl ester structure with the hydroxyl group. As a result, a good degree of curing can be obtained, and a cured product with excellent solvent resistance can be obtained. When the structural unit (d) has a carboxylic acid alkyl ester structure, both a deblocking reaction and an ester exchange reaction can be caused, but by adjusting the baking temperature, either reaction can be preferentially performed. The temperature of the baking treatment is preferably 75°C or more, and more preferably 80°C or more. When the temperature of the baking treatment is 250°C or less, it is preferred because it is a condition that a material with low heat resistance can withstand and the discoloration of the photosensitive resin composition or the photosensitive coloring composition can be suppressed. The photosensitive resin composition and the photosensitive coloring composition have good low-temperature curing properties. Therefore, according to the heat resistance of the substrate on which the resin cured film is formed, the temperature of the baking treatment can be set to 160°C or less. For example, when a resin substrate is used as the substrate, it can be set to 150°C or less, 120°C or less, or 100°C or less.

[0297] The baking treatment performed when producing the cured resin film can be performed, for example, for 10 minutes to 4 hours, preferably for 20 minutes to 2 hours, and can be appropriately determined according to the composition of the photosensitive resin composition or the photosensitive coloring composition, the temperature of the baking treatment, the film thickness of the coating film, etc.

[0298] The cured resin film is composed of a cured product of a photosensitive resin composition or a photosensitive coloring composition. Therefore, the cured resin film can be produced by a method of baking at a relatively low temperature, and has excellent solvent resistance.

[0299] <Color filter>

[0300] A color filter according to one embodiment has a coloring pattern composed of a cured product of a photosensitive coloring composition. The color filter preferably has a coloring pattern composed of a cured product of a photosensitive coloring composition, wherein the photosensitive coloring composition contains the following (A) to (E): 10 to 90 parts by mass of the copolymer (A), 10 to 90 parts by mass of the reactive diluent (B), 0.1 to 30 parts by mass of a photopolymerization initiator (C), 30 to 1,000 parts by mass of a solvent (D), and 3 to 80 parts by mass of a colorant (E), relative to 100 parts by mass of the total of the copolymer (A) and the reactive diluent (B).

[0301] The color filter may include, for example, a substrate, RGB pixels formed on the substrate, a black matrix formed at a boundary of each pixel, and a protective film formed on the pixels and the black matrix.

[0302] In the color filter, the pixels and the black matrix are colored patterns composed of a cured product of the above-mentioned photosensitive coloring composition. In the color filter, the configurations other than the materials of the pixels and the black matrix can be known.

[0303] The substrate used for the color filter is not particularly limited, and a glass substrate, silicon substrate, polycarbonate substrate, polyester substrate, polyamide substrate, polyamideimide substrate, polyimide substrate, aluminum substrate, printed circuit substrate, array substrate, etc. can be used appropriately according to the purpose.

[0304] <Color filter manufacturing method>

[0305] Next, an exemplary manufacturing method of a color filter is described. First, a coloring pattern is formed on a substrate. Specifically, according to the method shown below, a coloring pattern that becomes a black matrix formed at each pixel boundary and a coloring pattern that becomes each RGB pixel are sequentially formed on the substrate.

[0306] The coloring pattern can be formed by photolithography. Specifically, a photosensitive coloring composition is applied on a substrate to form a coating film. Then, the coating film is exposed through a photomask having a specified pattern shape, so that the exposed portion is photocured. Next, the unexposed portion of the coating film is developed with an alkaline aqueous solution. Then, the developed coating film is baked to form a coloring pattern having a specified pattern shape.

[0307] The method for applying the photosensitive coloring composition is not particularly limited, and a known method such as a screen printing method, a roll coating method, a curtain coating method, a spray coating method, and a spin coating method can be used.

[0308] Furthermore, after the photosensitive coloring composition is applied to the substrate, the substrate may be heated by a heating method such as a circulation oven, an infrared heater, a hot plate, etc., as needed to volatilize and remove the solvent (D) contained in the coating film. The conditions for heating the substrate to remove the solvent (D) are not particularly limited, and can be appropriately set according to the material of the substrate, the composition of the photosensitive coloring composition, the film thickness of the coating film, etc. The heating of the substrate can be performed at a temperature of 50° C. to 120° C. for 30 seconds to 30 minutes, for example.

[0309] Next, the coating film formed in this manner is irradiated with active energy rays such as ultraviolet rays, excimer lasers, etc. through a negative photomask, partially exposed, and the exposed portion is photocured. The amount of active energy rays irradiated to the coating film can be appropriately selected according to the composition of the photosensitive coloring composition, etc., and can be set to, for example, 30 to 2000 mJ / cm 2 The light source used for exposure is not particularly limited, and a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, a xenon lamp, a metal halide lamp, or the like can be used.

[0310] The aqueous alkali solution used in the development of the coating film is not particularly limited, and may be an aqueous solution of an inorganic alkali compound such as sodium carbonate, potassium carbonate, calcium carbonate, sodium hydroxide, potassium hydroxide, etc.; an aqueous solution of an amine compound such as ethylamine, diethylamine, dimethylethanolamine, etc.; an aqueous solution of a quaternary ammonium salt such as a sulfate, hydrochloride or p-toluenesulfonate of tetramethylammonium; an aqueous solution of an aniline compound 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, 3-methyl-4-amino-N-ethyl-N-β-methoxyethylaniline and their sulfates, hydrochlorides or p-toluenesulfonates, and an aqueous solution of the salt thereof; an aqueous solution of a p-phenylenediamine compound and its salt, etc. Furthermore, additives such as a defoamer and a surfactant may be added to the aqueous alkali solution as needed.

[0311] After developing the coating film using the above-mentioned aqueous alkaline solution, the coating film is preferably washed with water and dried.

[0312] The conditions for the baking treatment performed when manufacturing the color filter can be appropriately determined according to the composition of the photosensitive coloring composition, the thickness of the coating film, the material of the substrate, etc. The temperature of the baking treatment can be set to 70°C to 210°C, for example. When the baking temperature is above 70°C, good curing properties can be obtained and a cured product with excellent solvent resistance can be obtained. The baking temperature is preferably above 75°C, and more preferably above 80°C. When the baking temperature is below 210°C, it is preferred because a material with low heat resistance, such as a substrate with low heat resistance, can be used as a material for the color filter.

[0313] When a coloring pattern of a color filter is formed using a conventional photosensitive coloring composition, if the temperature of the baking treatment is set to 200°C or less, the solvent resistance of the coloring pattern is insufficient. In contrast, since the photosensitive coloring composition of one embodiment has good low-temperature curing properties, the temperature of the baking treatment can be lowered compared to the case of using a conventional photosensitive coloring composition while ensuring the solvent resistance of the coloring pattern. Specifically, the baking treatment temperature can be set to 160°C or less according to the heat resistance of the substrate on which the resin cured film is formed. For example, when a resin substrate is used as a substrate to form a coloring pattern, it can be set to 150°C or less, 120°C or less, or 100°C or less.

[0314] The baking treatment performed when manufacturing the color filter can be performed for, for example, 10 minutes to 4 hours, preferably 20 minutes to 2 hours, and can be appropriately determined according to the composition of the photosensitive coloring composition, the baking treatment temperature, the film thickness of the coating film, and the like.

[0315] The photosensitive coloring composition has good photocurability and low temperature curability. Therefore, when a coloring pattern is formed using the photosensitive coloring composition of one embodiment, if the temperature of the baking treatment is set to the same level as when a coloring pattern is formed using a conventional photosensitive coloring composition, the baking treatment time can be shortened and a color filter can be efficiently formed.

[0316] Using the above-mentioned method for manufacturing a coloring pattern, after forming a coloring pattern for each RGB pixel and a coloring pattern for a black matrix formed at the boundary of each pixel, a protective film is formed on the coloring pattern (each RGB pixel and the black matrix).

[0317] The method for producing the protective film is not particularly limited, and the protective film may be formed using the photosensitive resin composition of one embodiment, or may be formed using a known material and a known method.

[0318] A color filter is obtained through the above steps.

[0319] The color filter has a color pattern formed of a cured product of the above-mentioned photosensitive coloring composition. Therefore, the color pattern in the color filter can be formed by a method of baking at a low temperature. Therefore, the energy required for the baking process can be reduced.

[0320] In addition, the colorant (E) contained in the photosensitive coloring composition used as a material for the color filter can be used with low heat resistance. Therefore, the selectivity of the colorant (E) that can be used is increased. Therefore, the color pattern of the color filter that can be formed, for example, contains a colorant (E) with low heat resistance, and can exert the original characteristics of the colorant (E) with low heat resistance.

[0321] Furthermore, the colored pattern in the color filter can be formed on a substrate with low heat resistance such as a resin substrate without affecting the substrate. Therefore, the selectivity of the substrate that can be used is increased. Specifically, since the color filter can be formed on a substrate with low heat resistance such as a resin substrate, the display can be made flexible. In addition, since the colored pattern in the color filter has excellent solvent resistance, the color change is less.

[0322] Here, the case where a coloring pattern is produced by using a photosensitive coloring composition containing a photopolymerization initiator (C) and photocuring the photosensitive coloring composition is described as an example, but, for example, a photosensitive coloring composition containing a curing accelerator and a known epoxy resin is used instead of the photopolymerization initiator (C) contained in the photosensitive coloring composition, and after applying it on the substrate by a spray method, a coloring pattern composed of a cured product of the photosensitive coloring composition containing the copolymer (A) can be formed by a heating method.

[0323] <Image display device>

[0324] The image display element of one embodiment is provided with a color filter. In the image display element, as a structure other than the color filter, a known one can be adopted. As a specific example of the image display element, solid-state imaging elements such as a liquid crystal display element, an organic EL display element, a CCD element, and a CMOS element can be cited.

[0325] The components other than the color filter in the image display element can be manufactured by a known method. For example, when manufacturing a liquid crystal display element as an image display element, the following method can be used for manufacturing. First, a color filter is formed on a substrate using the above method. Then, electrodes, spacers, etc. are formed in sequence on the substrate with the color filter. Next, electrodes, etc. are formed on another substrate, which is arranged opposite to the substrate with the color filter and bonded. Then, a specified amount of liquid crystal is injected between the opposite substrates and sealed.

[0326] Since the image display element is equipped with a color filter having excellent solvent resistance, the color change is small.

[0327] Example

[0328] The present invention will be described in more detail below by way of Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[0329] The synthesis example of the copolymer (A) is shown below.

[0330] [Example 1 (Synthesis Example 1)]

[0331] (Synthesis of Resin Precursor (PA))

[0332] In a flask equipped with a stirrer, a dropping funnel, a condenser, a thermometer and a gas inlet tube, 268.47 g of propylene glycol monomethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) was placed as a solvent (PD), and the temperature was raised to 78° C. while stirring and nitrogen substitution was performed.

[0333] Next, 17.2 g (20 mol%) of methacrylic acid as a monomer (ma), 49.7 g (15 mol%) of 2-[(malic acid diethyl)carbonylamino]ethyl acrylate as a monomer (m-pb), 19.5 g (15 mol%) of 2-hydroxyethyl methacrylate as a monomer (mc), 90.3 g (30 mol%) of a reaction product of 2-isocyanatoethyl acrylate and diethyl malonate as a monomer (md), 36.8 g (20 mol%) of 2-ethylhexyl acrylate as a monomer (me), 64.0 g (30 parts by mass relative to 100 parts by mass of the total of the above monomer components) of propylene glycol monomethyl ether as a solvent (PD), and 34.2 g (16 parts by mass relative to 100 parts by mass of the total of the above monomer components) of 2,2′-azobis(2,4-dimethylvaleronitrile) (FUJIFILM Wako Pure Chemical Co., Ltd.) to prepare a raw material monomer solution.

[0334] Using a dropping funnel, the entire amount of the prepared raw material monomer solution was added dropwise to the solvent (PD) in the flask under a nitrogen atmosphere and normal pressure over a period of 1 hour. After the addition was completed, the solution in the flask was stirred and polymerized at 78° C. for 3 hours to obtain a solution containing a resin precursor (PA) and a solvent (PD).

[0335] (Preparation of resin precursor composition)

[0336] Under normal pressure set to a nitrogen atmosphere, 0.5 g (0.2 parts by mass relative to 100 parts by mass of the total monomer components of the resin precursor (PA)) of hydroquinone monomethyl ether (MEHQ) as a polymerization inhibitor and 0.5 g (0.2 parts by mass relative to 100 parts by mass of the total monomer components of the resin precursor (PA)) of 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) (manufactured by San-Apro Co., Ltd.) as a basic catalyst were added to a solution containing a resin precursor (PA) and a solvent (PD) in a flask to obtain a resin precursor composition.

[0337] (Synthesis of Copolymer (A))

[0338] The resin precursor composition was stirred in a flask at normal pressure set to a nitrogen environment, and maintained at 78°C for 300 minutes to convert the structural unit (pb) having a group represented by formula (1) contained in the resin precursor (PA) into a structural unit (b) having a group represented by formula (1-1) or formula (1-2). In this way, a reaction solution containing a copolymer (A) and a solvent (PD) was obtained. The weight average molecular weight, ethylenically unsaturated group equivalent and acid value of the copolymer (A) were measured according to the above method and recorded in Table 1. The blocked isocyanate group equivalent and hydroxyl group equivalent of the copolymer (A) were calculated and recorded in Table 1.

[0339] To the reaction solution containing the copolymer (A) and the solvent (PD) obtained in this manner, propylene glycol monomethyl ether acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) was added as a solvent (D) so that the components other than the solvent became 35% by mass, thereby obtaining a solution of the copolymer (A) of Example 1.

[0340] [Examples 2 to 9 (Synthesis Examples 2 to 9)]

[0341] Solutions of copolymers (A) of Examples 2 to 9 were obtained in the same manner as in Example 1 except that the monomers and blending amounts described in Table 1 were used. The weight average molecular weight, ethylenically unsaturated group equivalent, and acid value of the copolymers (A) of Examples 2 to 9 were measured according to the aforementioned method and are described in Table 1. The blocked isocyanate group equivalent and hydroxyl group equivalent of the copolymers (A) of Examples 2 to 9 were calculated and described in Table 1.

[0342] [Comparative Example 1 (Comparative Synthesis Example 1)]

[0343] In a flask equipped with a stirring device, a dropping funnel, a condenser, a thermometer and a gas inlet tube, 273.6 g of propylene glycol monomethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) was added as a solvent (PD), and the temperature was raised to 78° C. while stirring and nitrogen substitution was performed.

[0344] Next, 66.2 g (20 mol%) of 2-[(diethylmalate)carbonylamino]ethyl acrylate as a monomer (m-pb), 39.0 g (30 mol%) of 2-hydroxyethyl methacrylate as a monomer (mc), 31.5 g (10 mol%) of 2-[(3,5-dimethylpyrazolyl)carbonylamino)ethyl methacrylate as a monomer (md), 73.6 g (40 mol%) of 2-ethylhexyl acrylate as a monomer (me), 63.1 g (30 parts by mass relative to 100 parts by mass of the total of the above monomer components) of propylene glycol monomethyl ether as a solvent (PD), and 33.7 g (16 parts by mass relative to 100 parts by mass of the total of the above monomer components) of 2,2′-azobis(2,4-dimethylvaleronitrile) (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.) as a polymerization initiator were mixed to prepare a raw monomer solution.

[0345] Using a dropping funnel, the entire amount of the prepared raw material monomer solution was added dropwise to the solvent (PD) in the flask under a nitrogen atmosphere and normal pressure over a period of 1 hour. After the addition was completed, the solution in the flask was stirred and polymerized at 78° C. for 3 hours to obtain a solution containing a resin precursor (PA) and a solvent (PD).

[0346] (Preparation of resin precursor composition)

[0347] Under normal pressure set to a nitrogen atmosphere, 0.2 g (0.1 parts by mass relative to 100 parts by mass of the total monomer components of the resin precursor (PA)) of 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) (manufactured by San-Apro Co., Ltd.) as a basic catalyst was added to a solution containing a resin precursor (PA) and a solvent (PD) in a flask to obtain a resin precursor composition.

[0348] (Synthesis of Copolymer)

[0349] In the resin precursor composition, 10 g (10 moles relative to a total of 100 moles of monomers used in the synthesis of the resin precursor (PA)) of succinic anhydride (SA) (manufactured by Shin Nippon Rika Co., Ltd.) and 0.9 g (0.4 parts by mass relative to a total of 100 parts by mass of monomers and succinic anhydride used in the synthesis of the resin precursor (PA)) of lithium cyclohexane (manufactured by Toei Chemical Co., Ltd.) as a catalyst were added, and the addition reaction was carried out at 78°C for 300 minutes, while the structural unit (pb) having a group represented by formula (1) contained in the resin precursor (PA) was converted into a structural unit (b) having a group represented by formula (1-1) or formula (1-2). In this way, a reaction solution containing a copolymer (cA) and a solvent (PD) was obtained. The weight average molecular weight, ethylenically unsaturated group equivalent and acid value of the copolymer (cA) were measured according to the above method and are recorded in Table 1. The blocked isocyanate group equivalent and the hydroxyl group equivalent of the copolymer (cA) were calculated and shown in Table 1.

[0350] To the reaction solution containing the copolymer (cA) and the solvent (PD) obtained in this manner, propylene glycol monomethyl ether acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) was added as a solvent (D) so that the components other than the solvent became 35% by mass, thereby obtaining a solution of the copolymer (cA) of Comparative Example 1.

[0351] [Comparative Example 2 (Comparative Synthesis Example 2)]

[0352] In a flask equipped with a stirring device, a dropping funnel, a condenser, a thermometer and a gas inlet tube, 241.2 g of propylene glycol monomethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) was added as a solvent (PD), and the temperature was raised to 78° C. while stirring and nitrogen substitution was performed.

[0353] Next, 15.5 g (18 mol%) of methacrylic acid as a monomer (ma), 18.2 g (14 mol%) of 2-hydroxyethyl methacrylate as a monomer (mc), 60.2 g (20 mol%) of a reaction product of 2-isocyanatoethyl acrylate and diethyl malonate as a monomer (md), 88.3 g (48 mol%) of 2-ethylhexyl acrylate as a monomer (me), 54.7 g (30 parts by mass relative to 100 parts by mass of the total of the above monomer components) of propylene glycol monomethyl ether as a solvent (PD), and 29.2 g (16 parts by mass relative to 100 parts by mass of the total of the above monomer components) of 2,2′-azobis(2,4-dimethylvaleronitrile) (manufactured by FUJIFILM Wako Pure Chemical Co., Ltd.) as a polymerization initiator were mixed to prepare a raw monomer solution.

[0354] Using a dropping funnel, under normal pressure set to a nitrogen environment, the entire amount of the prepared raw monomer solution was added dropwise to the solvent (PD) in the flask over a period of 1 hour. After the addition was completed, the solution in the flask was stirred and polymerized at 78°C for 3 hours to obtain a reaction solution containing a copolymer (cA) and a solvent (PD). The weight average molecular weight, ethylenically unsaturated group equivalent, and acid value of the copolymer (cA) were measured according to the aforementioned method and are recorded in Table 1. The blocked isocyanate group equivalent and hydroxyl group equivalent of the copolymer (cA) were calculated and recorded in Table 1.

[0355] To the reaction solution containing the copolymer (cA) and the solvent (PD) obtained in this manner, propylene glycol monomethyl ether acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) was added as a solvent (D) so that the components other than the solvent became 35% by mass, thereby obtaining a solution of the copolymer (cA) of Comparative Example 2.

[0356]

[0357] The compounds described in Table 1 were respectively as follows.

[0358] MAA: methacrylic acid (manufactured by KURARAY Co., Ltd.)

[0359] AOI-MDE: Karenz (trademark) AOI-MDE, 2-[(malic acid diethyl ester) carbonylamino]ethyl acrylate (manufactured by Showa Denko K.K.)

[0360] AOI-DEM: Karenz (trademark) AOI-DEM, reaction product of 2-isocyanateethyl acrylate and diethyl malonate (manufactured by Showa Denko K.K.)

[0361] MOI-BP: Karenz (trademark) MOI-BP, 2-[(3,5-dimethylpyrazolyl)carbonylamino]ethyl methacrylate (manufactured by Showa Denko K.K.)

[0362] MOI-BM: Karenz (trademark) MOI-BM, 2-[(butanone oxime)carbonylamino]ethyl methacrylate (manufactured by Showa Denko K.K.)

[0363] HEMA: 2-Hydroxyethyl methacrylate (manufactured by Nippon Catalyst Co., Ltd.)

[0364] 4HBA: 4-Hydroxybutyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd.)

[0365] 2EHA: 2-Ethylhexyl acrylate (manufactured by Toagosei Co., Ltd.)

[0366] SA: Succinic anhydride (manufactured by New Nippon Rika Co., Ltd.)

[0367] DBU: 1,8-diazabicyclo[5.4.0]-7-undecene (manufactured by San-Apro Co., Ltd.)

[0368] [Evaluation of storage stability]

[0369] 10 mL of the solution of the copolymer (A) obtained in Example 1 was measured into a 20 mL sample bottle, which was sealed and stored at 5°C for 3 months. The weight average molecular weight of the sample after storage was measured, and the increase rate of the weight average molecular weight was calculated according to the following formula. The increase rate of the weight average molecular weight was also calculated for the solutions of the copolymers (A) or (cA) obtained in Examples 2 to 9 and Comparative Examples 1 to 2. The increase rate of the weight average molecular weight is shown in Table 1. When the increase rate is within 20%, the storage stability is good.

[0370] Increase rate of weight average molecular weight (%) = (weight average molecular weight after storage - weight average molecular weight before storage) / weight average molecular weight before storage × 100

[0371] [Examples 10 to 18, Comparative Examples 3 to 4]

[0372] The copolymers (A) of Synthesis Examples 1 to 9 shown in Table 2 or the copolymers (cA) of Comparative Synthesis Examples 1 to 2, dipentaerythritol pentaacrylate (manufactured by Toagosei Co., Ltd.) as a reactive diluent (B), 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl-]-,-1-(O-acetoxime) (manufactured by Ciba Japan Co., Ltd.) as a photopolymerization initiator (C), a mixture of propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether (338 parts by mass and 257 parts by mass, respectively) as a solvent (D), and Valifast Blue 2620 (phthalocyanine dye, manufactured by ORIENT Chemical Industry Co., Ltd.) as a colorant (E) were mixed in the proportions shown in Table 2 to prepare photosensitive coloring compositions of Examples 10 to 18 and Comparative Examples 3 to 4.

[0373] The amount of the solvent is not included in the amount of the copolymer (A) or (cA) formulated in Table 2. The amount of the solvent (D) formulated in Table 2 is the total amount of the solvent contained in the solution of the copolymer (A) or (cA) obtained in Synthesis Examples 1 to 9 and Comparative Synthesis Examples 1 to 2 and the amount of the solvent added when preparing the photosensitive coloring composition.

[0374]

[0375] [Evaluation of solvent resistance]

[0376] Solvent resistance was evaluated by the residual film rate.

[0377] (residual film rate)

[0378] The photosensitive coloring compositions of Examples 10 to 18 and Comparative Examples 3 to 4 were applied to a 5 cm long, 5 cm wide square glass substrate (alkali-free glass substrate) in plan view by spin coating to form a coating film so that the thickness after exposure was 2.5 μm. Next, the solvent (D) in the coating film was volatilized by heating at 100° C. for 3 minutes.

[0379] Next, the energy dose was 100 mJ / cm 2 The coating film was exposed by irradiating ultraviolet rays with a wavelength of 365 nm, and the exposed portion was photocured. Then, the coating film was cured by baking at 100° C. for 20 minutes to form a cured film. The thickness of the prepared cured film was measured using a height difference meter. The thickness at this time was set to X.

[0380] Then, the prepared cured film was immersed in 20 g of propylene glycol monomethyl ether acetate (PGMEA) at 23° C. for 15 minutes. The immersed coating film was vacuum dried at 40° C. for 30 minutes, and then the thickness of the coating film was measured using a height difference meter. The thickness at this time was defined as Y.

[0381] According to the following formula, the ratio of the thickness Y of the cured film after PGMEA impregnation to the thickness X of the cured film before PGMEA impregnation is calculated as the residual film rate, and the solvent resistance of the cured film is evaluated. That is, the closer the residual film rate is to 100%, the better the solvent resistance of the cured film is. As an evaluation, a residual film rate of 80% or more is set as the qualified line. The residual film rate of the cured film is shown in Table 2.

[0382] Residual film rate = (Y / X) × 100 (%)

[0383] As shown in Table 2, the residual film ratio (%) of the cured films of the resin compositions of Examples 10 to 18 after immersion in PGMEA was 85% or more, and the solvent resistance was good even at a low temperature of 100°C for the baking treatment.

[0384] [Evaluation of Development Properties]

[0385] The developability was evaluated based on the solubility and adhesion of the cured film.

[0386] (Solubility)

[0387] The photosensitive coloring compositions prepared in Examples 10 to 18 and Comparative Examples 3 to 4 were applied to a 5 cm square glass substrate (alkali-free glass substrate) by spin coating so that the thickness after exposure was 1.5 μm (coating step). The glass substrate coated with the photosensitive coloring composition was heated at 100° C. for 3 minutes to volatilize the solvent and dry the coating film (pre-baking step).

[0388] Next, the surface of the dried coating film was irradiated with 100 mJ / cm2 using an ultra-high pressure mercury lamp through a photomask. 2 The exposure step is performed by setting a photomask at a distance of 100 μm from the coating film. A photomask having a line and space pattern with a width of 3 to 100 μm is used as a photomask. Next, the unexposed portion is removed by spraying Semi clean DL-A10 developer (manufactured by Yokohama Oil & Fats Industries) (300 times diluted) on the surface of the coating film at a temperature of 23°C and a pressure of 0.1 MPa for 60 seconds (development step). The dissolution morphology of the coating film when the developer is sprayed is observed, and the solubility is evaluated according to the following criteria. The results are shown in Table 2.

[0389] 1: There is no residue in the unexposed part, and no powder is found in the developer. The pattern shape is good.

[0390] 2: Although there is no residue in the unexposed part, powder is found in the developer, and the pattern shape is relatively good

[0391] 3: There are residues in the unexposed part, and the pattern shape is defective.

[0392] 4: The exposed part of the film peels off, and no pattern remains

[0393] (Adhesion)

[0394] The glass substrate with the coating film after the development step was placed in a dryer at 100° C. for 30 minutes to thermally cure the coating film (post-baking step) to obtain a colored pattern. The colored pattern obtained in this manner was observed using a microscope, and the adhesion was evaluated based on the minimum line width that can be developed (minimum development size (μm)). The results are shown in Table 2.

[0395] Industrial Availability

[0396] According to the present invention, a photosensitive resin composition can be provided, which can obtain a resin cured film having excellent solvent resistance. In addition, according to the present invention, an image display element having a color filter can be provided, and the color filter has a color pattern composed of a resin cured film having excellent solvent resistance. The photosensitive resin composition and the photosensitive coloring composition can be preferably used as a material for a transparent film, a protective film, an insulating film, a protective layer, a photosensitive spacer, a black matrix, a black column spacer, a resist for a color filter, and the like.

Claims

1. A copolymer having: The structural unit a having an acid group, and A structural unit b having a group represented by the following formula (1-1) or the following formula (1-2), In formula (1-1), R 1 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, * represents a site connected to the residue after removing the group of formula (1-1) from the structural unit b, In formula (1-2), R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, R 4 is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and * represents a site connected to the residue obtained by removing the group of formula (1-2) from the structural unit b.

2. The copolymer according to claim 1, further comprising: A structural unit c having a hydroxyl group, and A structural unit d having a blocked isocyanate group. 3 . The copolymer according to claim 2 , wherein the blocking agent of the structural unit d having a blocked isocyanate group is at least one selected from 3,5-dimethylpyrazole, butanone oxime, methyl 4-hydroxybenzoate, methyl 2-hydroxybenzoate and 3,5-dimethylphenol. 4 . The copolymer according to claim 2 , wherein the blocking agent of the structural unit d having a blocked isocyanate group has a carboxylic acid alkyl ester structure.

5. The copolymer according to claim 2, wherein the structural unit d having a blocked isocyanate group has a group represented by the following formula (2) or a group represented by the following formula (3), In formula (2), R 5 and R 6 Each independently represents an alkyl group having 1 to 10 carbon atoms, n1 and n2 each independently represent an integer of 0 to 2, * represents a site connected to the residue after removing the blocked isocyanate group from the structural unit d, In formula (3), R 7 and R 8 Each independently represents an alkyl group having 1 to 10 carbon atoms, n3 and n4 each independently represent an integer of 0 to 2, and * represents a site to which the residue obtained by removing the blocked isocyanate group from the structural unit d is bonded.

6. The copolymer according to claim 2, further comprising another structural unit e in addition to the structural units a to d, The structural unit e is a structural unit derived from an alkyl (meth)acrylate having an alkyl group with 1 to 12 carbon atoms.

7. The copolymer according to claim 1, having an acid value of 10 to 300 KOHmg / g.

8. The copolymer according to claim 1, comprising 3 to 40 mol% of the structural unit b.

9. The copolymer according to claim 1, having a weight average molecular weight of 1,000 to 50,000, The ethylenically unsaturated group equivalent is 300 to 8000 g / mol.

10. A photosensitive resin composition comprising: The copolymer A as the copolymer according to any one of claims 1 to 9, Reactive diluent B, Photopolymerization initiator C, and Solvent D.

11. The photosensitive resin composition according to claim 10, wherein relative to 100 parts by mass of the total of the copolymer A and the reactive diluent B, Containing 10 to 90 parts by weight of the copolymer A, Containing 10 to 90 parts by mass of the reactive diluent B, Containing 0.1 to 30 parts by weight of the photopolymerization initiator C, The solvent D is contained in an amount of 30 to 1000 parts by mass. 12 . A photosensitive coloring composition comprising the photosensitive resin composition according to claim 10 and a colorant (E).

13. The photosensitive coloring composition according to claim 12, wherein the copolymer A and the reactive diluent B are contained in an amount of 100 parts by mass in total. Containing 10 to 90 parts by weight of the copolymer A, Containing 10 to 90 parts by mass of the reactive diluent B, Containing 0.1 to 30 parts by weight of the photopolymerization initiator C, Contains 30 to 1000 parts by mass of the solvent D, The colorant E is contained in an amount of 3 to 80 parts by mass. 14 . A cured resin film, comprising a cured product of the photosensitive resin composition according to claim 10 . 15 . A cured resin film composed of a cured product of the photosensitive coloring composition according to claim 12 . 16 . A color filter having a colored pattern consisting of a cured product of the photosensitive coloring composition according to claim 12 .

17. An image display device comprising the color filter according to claim 16.

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