Copolymer

Abstract

A copolymer obtained by adding an ethylenically unsaturated compound (e) having an acid group-reactive functional group to part of an acid group of an acid group-containing structural unit (a-3) in a copolymer precursor including a block isocyanate group-containing structural unit (a-1), a hydroxy group-containing structural unit (a-2), and the acid group-containing structural unit (a-3).

Description

copolymer

[0001] The present disclosure relates to copolymers having ethylenically unsaturated groups.

[0002] 2. Description of the Related Art In recent years, with the widespread use of liquid crystal displays, there has been much research being conducted on color filters used as components of liquid crystal displays, as well as on overcoat layers and interlayer insulating films provided on these color filters.

[0003] Japanese Patent Application Laid-Open No. 2019-53266

[0004] The present disclosure provides a copolymer with excellent storage stability that provides a cured resin film having excellent solvent resistance, and that provides a photosensitive resin composition and a photosensitive colored composition with good developability.

[0005] The present disclosure includes the following aspects. [1] A copolymer in which an ethylenically unsaturated compound (e) having a functional group reactive with an acid group is added to a portion of the acid group of the acid group-containing structural unit (a-3) of a copolymer precursor containing a structural unit (a-1) having a blocked isocyanato group, a structural unit (a-2) having a hydroxy group, and a structural unit (a-3) having an acid group. [2] The copolymer according to [1], which has an ethylenically unsaturated group equivalent of 200 to 4,000 g / mol. [3] The copolymer according to [1] or [2], which has an acid value of 10 to 300 KOH mg / g. [4] The copolymer according to any one of [1] to [3], which has a blocked isocyanato group equivalent of 200 to 6,000 g / mol and a hydroxyl group equivalent of 100 to 4,000 g / mol. [5] The copolymer according to any one of [1] to [4], having a weight average molecular weight (Mw) of 1,000 to 50,000 and a molecular weight distribution (Mw / Mn) of 1.3 to 5.0. [6] The copolymer according to any one of [1] to [5], wherein the blocked isocyanato group of the structural unit (a-1) having the blocked isocyanato group is a group represented by the following formula (1) or the following formula (2): (In formula (1), R １ and R ２each independently represents an alkyl group having 1 to 10 carbon atoms, and * represents the linking site with the residue remaining after removing the blocked isocyanato group from the structural unit (a-1) having the blocked isocyanato group. (In formula (2), R ３ represents an alkyl group having 1 to 10 carbon atoms, and * represents a linking site with the residue remaining after removing the blocked isocyanato group from the structural unit (a-1) having a blocked isocyanato group.) [7] The copolymer according to any one of [1] to [5], wherein the blocking agent that constitutes the blocked isocyanato group of the structural unit (a-1) having a blocked isocyanato group is at least one compound selected from the group consisting of pyrazole compounds, oxime compounds, and phenol compounds. [8] The structural unit (a-2) having a hydroxy group is a -CH ２ The copolymer according to any one of [1] to [7], wherein the structural unit (a-2) having a hydroxy group is a structural unit having a group represented by —OH. [9] The structural unit (a-2) having a hydroxy group is —(CH ２ ) ｎ A structural unit having a group represented by —OH (n is an integer of 2 to 6) and —(O—C ｘ H ２ｘ ) ｍThe copolymer according to any one of [1] to [8], wherein the ethylenically unsaturated compound (e) is at least one selected from the group consisting of structural units having a group represented by -OH (x is an integer of 2 to 4, and m is an integer of 2 to 6).

[10] The copolymer according to any one of [1] to [9], wherein the ethylenically unsaturated compound (e) is an epoxy group-containing (meth)acrylate.

[11] The copolymer according to any one of [1] to

[10] , wherein, of all the structural units of the copolymer precursor, the content of structural units (a-1) having the blocked isocyanato group is 5 to 40 mol %, the content of structural units (a-2) having the hydroxy group is 1 to 35 mol %, and the content of structural units (a-3) having the acid group is 5 to 70 mol %, the amount of the ethylenically unsaturated compound (e) added is 1 to 55 mol per 100 mol of the structural units of the copolymer precursor, and the amount of the ethylenically unsaturated compound (e) added is 1 to 85 mol per 100 mol of the structural units (a-3) having the acid group of the copolymer precursor.

[12] The copolymer according to any one of [1] to

[11] , wherein the dissociation rate of the blocked isocyanate group in the structural unit (a-1) having the blocked isocyanate group when heat-treated at 100°C for 30 minutes is 5 to 99%.

[0006] According to the present disclosure, it is possible to provide a copolymer having excellent storage stability that gives a cured resin film having excellent solvent resistance and gives a photosensitive resin composition and a photosensitive coloring composition that have good developability.

[0007] Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to the embodiments described below.

[0008] In this specification, when "to" is used to describe a numerical range, the numerical values ​​at both ends are the upper and lower limits, respectively, and are included in the numerical range. When multiple upper or lower limits are listed, numerical ranges can be created using all combinations of the upper and lower limits. Similarly, when multiple numerical ranges are listed, separate numerical ranges can be created by individually selecting and combining the upper and lower limits from those numerical ranges.

[0009] In this specification, "(meth)acrylic acid" means methacrylic acid or acrylic acid, "(meth)acrylate" means acrylate or methacrylate, and "(meth)acryloyloxy" means acryloyloxy or methacryloyloxy. In this specification, "(poly)alkylene glycol" means alkylene glycol or polyalkylene glycol.

[0010] In this specification, the term "ethylenically unsaturated bond" refers to a double bond formed between carbon atoms excluding carbon atoms forming an aromatic ring, the term "ethylenically unsaturated group" refers to a group having an ethylenically unsaturated bond, and the term "ethylenically unsaturated compound" refers to a compound having an ethylenically unsaturated bond.

[0011] In this specification, the term "structural unit" refers to a unit derived from the polymerizable compound itself used as a monomer, or a unit obtained by further modifying a unit derived from the polymerizable compound itself used as a monomer after polymerization.

[0012] <Copolymer> The copolymer of one embodiment is a copolymer in which an ethylenically unsaturated compound (e) (also referred to simply as "compound (e)") having a functional group reactive with an acid group is added to a portion of the acid group of the acid group-containing structural unit (a-3) of a copolymer precursor containing a structural unit (a-1) (also referred to simply as "structural unit (a-1)") having a blocked isocyanato group, a structural unit (a-2) (also referred to simply as "structural unit (a-2)") having a hydroxy group, and a structural unit (a-3) (also referred to simply as "structural unit (a-3)"). The copolymer precursor may, if necessary, contain a structural unit (a-4) other than the structural units (a-1) to (a-3).

[0013] The ethylenically unsaturated group equivalent of the copolymer is preferably 200 g / mol or more, more preferably 400 g / mol or more, and even more preferably 500 g / mol or more. The ethylenically unsaturated group equivalent of the copolymer is preferably 4,000 g / mol or less, more preferably 3,000 g / mol or less, even more preferably 2,000 g / mol or less, and particularly preferably 1,000 g / mol or less. When the ethylenically unsaturated group equivalent of the copolymer is 200 g / mol or more, the storage stability of the photosensitive resin composition or photosensitive coloring composition using this copolymer is better. When the ethylenically unsaturated group equivalent of the copolymer is 4,000 g / mol or less, the solvent resistance of the cured product of the photosensitive resin composition or photosensitive coloring composition using this copolymer is better.

[0014] The ethylenically unsaturated group equivalent is the mass of the copolymer per mole of ethylenically unsaturated groups in the copolymer. The ethylenically unsaturated group equivalent can be determined by dividing the mass of the copolymer by the number of ethylenically unsaturated groups in the copolymer (g / mol). In this specification, the ethylenically unsaturated group equivalent of the copolymer is a value calculated from the amount of raw materials used in producing the copolymer and the addition reaction rate of compound (e). The addition reaction rate of compound (e) is calculated by the method described in the examples.

[0015] The acid value of the copolymer is preferably 10 KOHmg / g or more, more preferably 20 KOHmg / g or more, and even more preferably 30 KOHmg / g or more. The acid value of the copolymer is preferably 300 KOHmg / g or less, more preferably 200 KOHmg / g or less, and even more preferably 100 KOHmg / g or less. When the acid value of the copolymer is 10 KOHmg / g or more, the developability of a photosensitive resin composition or a photosensitive coloring composition using this copolymer is better. When the acid value of the copolymer is 300 KOHmg / g or less, the storage stability of a photosensitive resin composition or a photosensitive coloring composition using this copolymer is better.

[0016] The acid value of the copolymer is 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 milligrams of potassium hydroxide required to neutralize the acidic components contained in 1 g of the copolymer.

[0017] The block isocyanato group equivalent of the copolymer is preferably 200 g / mol or more, more preferably 300 g / mol or more, and even more preferably 400 g / mol or more. The block isocyanato group equivalent of the copolymer is preferably 6,000 g / mol or less, more preferably 4,000 g / mol or less, even more preferably 2,000 g / mol or less, and particularly preferably 1,000 g / mol or less. When the block isocyanato group equivalent of the copolymer is 200 g / mol or more, the storage stability of a photosensitive resin composition or a photosensitive coloring composition using this copolymer is better. When the block isocyanato group equivalent of the copolymer is 6,000 g / mol or less, the low-temperature curability of a photosensitive resin composition or a photosensitive coloring composition using this copolymer is good, and the solvent resistance of the cured product is better.

[0018] The block isocyanato group equivalent is the mass of the copolymer per mole of the block isocyanato groups in the copolymer. The block isocyanato group equivalent can be determined by dividing the mass of the copolymer by the number of block isocyanato groups in the copolymer (g / mol). In this specification, the block isocyanato group equivalent of the copolymer is a theoretical value calculated from the amounts of raw materials used in producing the copolymer.

[0019] The hydroxyl group equivalent of the copolymer is preferably 100 g / mol or more, more preferably 150 g / mol or more, even more preferably 300 g / mol or more, and particularly preferably 400 g / mol or more. The hydroxyl group equivalent of the copolymer is preferably 4,000 g / mol or less, more preferably 3,000 g / mol or less, even more preferably 2,000 g / mol or less, and particularly preferably 1,000 g / mol or less. When the hydroxyl group equivalent of the copolymer is 100 g / mol or more, the storage stability of the photosensitive resin composition or photosensitive coloring composition using this copolymer is better. When the hydroxyl group equivalent of the copolymer is 4,000 g / mol or less, the low-temperature curing property of the photosensitive resin composition or photosensitive coloring composition using this copolymer is good, and the solvent resistance of the cured product is better.

[0020] The hydroxyl equivalent is the mass of the copolymer per mole of hydroxy groups in the copolymer. The hydroxyl equivalent is a value calculated based on the hydroxyl value measured using a mixed indicator of bromothymol blue and phenol red according to JIS K0070:1992. The hydroxyl value of the copolymer refers to the number of milligrams of potassium hydroxide required to neutralize the acetic acid bonded to the hydroxyl groups when 1 g of the copolymer is acetylated. The hydroxyl equivalent of the copolymer can be calculated by converting the number of milligrams of potassium hydroxide required for neutralization into moles and determining the mass of the copolymer per mole.

[0021] The weight average molecular weight (Mw) of the copolymer is preferably 1,000 or more, more preferably 2,000 or more, and even more preferably 4,000 or more. The weight average molecular weight of the copolymer is preferably 50,000 or less, more preferably 30,000 or less, and even more preferably 10,000 or less. When the weight average molecular weight of the copolymer is 1,000 or more, the low-temperature curing properties of the photosensitive resin composition or photosensitive coloring composition using this copolymer are good. When the weight average molecular weight of the copolymer is 50,000 or less, the storage stability of the photosensitive resin composition or photosensitive coloring composition using this copolymer is better.

[0022] The molecular weight distribution (Mw / Mn) of the copolymer is preferably 1.3 or more, more preferably 1.5 or more, even more preferably 1.7 or more, and particularly preferably 1.9 or more. The molecular weight distribution (Mw / Mn) of the copolymer is preferably 5.0 or less, more preferably 4.5 or less, even more preferably 4.0 or less, and particularly preferably 3.5 or less. When the molecular weight distribution (Mw / Mn) of the copolymer is 1.3 or more, it is easy to control the production conditions during copolymer synthesis. When the molecular weight distribution (Mw / Mn) of the copolymer is 5.0 or less, the storage stability is better.

[0023] In this specification, the weight average molecular weight (Mw) and number average molecular weight (Mn) are values ​​measured using gel permeation chromatography (GPC) under the following conditions and determined using a standard polystyrene calibration curve. Column: Two Showdex (trademark) LF-804 (Resonac Corporation) connected in series. Column temperature: 40°C. Sample: 0.2% by mass solution of the object to be measured in tetrahydrofuran. Developing solvent: tetrahydrofuran. Detector: differential refractometer (Shodex (trademark) RI-71S) (Resonac Corporation). Flow rate: 1 mL / min.

[0024] (Structural Unit (a-1) Having a Blocked Isocyanato Group) The structural unit (a-1) having a blocked isocyanato group is not particularly limited, as long as it has a structure in which the isocyanato group is blocked by the addition of a blocking agent. The structural unit (a-1) may be of only one type, or may be of two or more types. The structural unit (a-1) is a structural unit derived from a blocked isocyanato group-containing monomer (ma-1) (hereinafter also simply referred to as "monomer (ma-1)"). When the copolymer contains the structural unit (a-1), crosslinking with the structural unit (a-2) having a hydroxy group progresses when a photosensitive resin composition or photosensitive coloring composition using this copolymer is heated. As a result, the obtained cured product has good solvent resistance even under low-temperature curing conditions. The crosslinking is formed, for example, by a reaction between an isocyanato group generated by dissociation of the blocking agent and a hydroxy group. When the blocking agent is a compound having an alkyloxycarbonyl group, crosslinking can be formed by transesterification between the alkyl group of the alkyloxycarbonyl group and the structural unit (a-2) having a hydroxy group, even if dissociation of the blocking agent does not occur.

[0025] In one embodiment, the monomer (ma-1) has an ethylenically unsaturated bond and a blocked isocyanato group. The monomer (ma-1) may be used alone or in combination of two or more types. Examples of the monomer (ma-1) include a compound in which the isocyanato group of an isocyanate compound having an ethylenically unsaturated bond and an isocyanato group is blocked with a blocking agent. Examples of the ethylenically unsaturated group contained in the monomer (ma-1) include a vinyl group and a (meth)acryloyloxy group.

[0026] The blocking reaction between an isocyanate compound and a blocking agent during the production of monomer (ma-1) can be carried out regardless of the presence or absence of a solvent. When the blocking reaction is carried out using a solvent, the solvent used may be any solvent inactive to the isocyanato group, and known solvents can be used. In the blocking reaction, an organic metal salt containing a metal such as tin, zinc, or lead, or a tertiary amine may be used as a catalyst. The blocking reaction can generally be carried out at a temperature of −20 to 150° C., and preferably at a temperature of 0 to 100° C.

[0027] The isocyanate compound used as a raw material for the monomer (ma-1) includes, for example, a compound represented by the following formula (3):

[0028] (In formula (3), R ４ represents a hydrogen atom or a methyl group; R ５ is -CO-, -COOR ６ - (where R ６ is an alkylene group having 1 to 6 carbon atoms, or —COO—R ７ O-CONH-R ８ - (where R ７ is an alkylene group having 2 to 6 carbon atoms, and R ８ represents an alkylene group having 2 to 12 carbon atoms or an arylene group having 6 to 12 carbon atoms, which may have a substituent.

[0029] In the isocyanate compound represented by formula (3), R ５ is preferably selected from -COOR because of the high reactivity of the isocyanato group after deblocking and the ease of preparing the isocyanate compound. ６ - is preferred, and R ６ More preferably, is an alkylene group having 1 to 4 carbon atoms.

[0030] Specific examples of the isocyanate compound represented by the above formula (3) include 2-isocyanatoethyl (meth)acrylate, 2-isocyanatopropyl (meth)acrylate, 3-isocyanatopropyl (meth)acrylate, 2-isocyanato-1-methylethyl (meth)acrylate, 2-isocyanato-1,1-dimethylethyl (meth)acrylate, 4-isocyanatocyclohexyl (meth)acrylate, and methacryloyl isocyanate.

[0031] As the isocyanate compound used as a raw material for the monomer (ma-1), a reaction product obtained by reacting an equimolar amount of a hydroxyalkyl (meth)acrylate with a diisocyanate compound (hydroxyalkyl (meth)acrylate:diisocyanate compound=1 mol:1 mol) may be used.

[0032] The alkyl group of the hydroxyalkyl (meth)acrylate is preferably an ethyl group or an n-propyl group, more preferably an ethyl group, in view of the good reactivity of the isocyanato group after deblocking and the ease of reaction.

[0033] Examples of the diisocyanate compound include hexamethylene diisocyanate, 2,4- (or 2,6-) tolylene 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.

[0034] Examples of the other isocyanate compounds used as raw materials for the monomer (ma-1) 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.

[0035] From the viewpoint of low-temperature curing properties of a photosensitive resin composition or a photosensitive coloring composition containing the copolymer, the structural unit (a-1) having a blocked isocyanato group is preferably a structural unit derived from a blocked isocyanato group-containing (meth)acrylate. When the monomer (ma-1) is a blocked isocyanato group-containing (meth)acrylate, the isocyanate compound used as a raw material thereof is an isocyanato group-containing (meth)acrylate.

[0036] Examples of isocyanato group-containing (meth)acrylates include 2-isocyanatoethyl (meth)acrylate, 2-isocyanatopropyl (meth)acrylate, 3-isocyanatopropyl (meth)acrylate, 2-isocyanato-1-methylethyl (meth)acrylate, 2-isocyanato-1,1-dimethylethyl (meth)acrylate, 4-isocyanatocyclohexyl (meth)acrylate, and 1,1-bis(methacryloyloxymethyl)ethyl isocyanate. Of these, 2-isocyanatoethyl (meth)acrylate, 2-isocyanatopropyl (meth)acrylate, and 1,1-bis(methacryloyloxymethyl)ethyl isocyanate are preferred.

[0037] Examples of blocking agents for blocking isocyanato groups include lactam compounds such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, and β-propiolactam; alcohol compounds such as methanol, ethanol, propanol, 1-methoxy-2-propanol, butanol, ethylene glycol, methyl cellosolve, butyl cellosolve, methyl carbitol, benzyl alcohol, phenyl cellosolve, furfuryl alcohol, and cyclohexanol; phenol compounds such as phenol, 2,6-dimethylphenol, cresol, 3,5-xylenol, ethylphenol, o-isopropylphenol, and butylphenols 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, and ethyl acetoacetate. active methylene compounds such as acetylacetone; mercaptan compounds such as butyl mercaptan, thiophenol, tert-dodecyl mercaptan; amine compounds such as diisopropylamine, diphenylamine, phenylnaphthylamine, aniline, carbazole; acid amide compounds such as acetanilide, acetanisidide, acetic acid amide, benzamide; imide compounds such as succinimide, maleic acid imide; imidazole compounds such as imidazole, 2-methylimidazole, 2-ethylimidazole; pyridine compounds such as pyridine, 2-methylimidazole, 2-ethylimidazole; Examples of blocking agents include pyrazole compounds such as pyrazole and 3,5-dimethylpyrazole; urea compounds such as urea, thiourea, and ethyleneurea; carbamic acid compounds such as N-phenylphenylcarbamate and 2-oxazolidone; imine compounds such as ethyleneimine and polyethyleneimine; oxime compounds such as formaldoxime, acetaldoxime, acetoxime, methyl ethyl ketoxime, methyl isobutyl ketoxime, and cyclohexanone oxime; and bisulfites such as sodium bisulfite and potassium bisulfite. The blocking agents may be used alone or in combination of two or more.

[0038] In one embodiment, as the blocking agent, from the viewpoint of low-temperature curing properties of the photosensitive resin composition or photosensitive coloring composition containing the copolymer, at least one selected from the group consisting of a pyrazole compound, an oxime compound, and a phenol compound is preferable, at least one selected from 3,5-dimethylpyrazole, methyl 4-hydroxybenzoate, and methyl ethyl ketoxime is more preferable, and at least one selected from 3,5-dimethylpyrazole and methyl ethyl ketoxime is even more preferable.

[0039] In the structural unit (a-1) having a blocked isocyanato group, the highly reactive isocyanato group is protected by a blocking agent. By heating a photosensitive resin composition or photosensitive coloring composition containing a copolymer including the structural unit (a-1), the blocked isocyanato group of the structural unit (a-1) can be dissociated, thereby regenerating the isocyanato group. The regenerated isocyanato group reacts with a reactive functional group contained in the copolymer to form a cured product with a high crosslinking density. Examples of reactive functional groups contained in the copolymer include a hydroxy group contained in the structural unit (a-2), an acid group contained in the structural unit (a-3), and an amino group contained in other structural units (a-4) that are contained as needed.

[0040] In the structural unit (a-1) having a blocked isocyanato group, the dissociation rate of the blocked isocyanato group when heated at 100°C for 30 minutes is preferably 5 to 99%, more preferably 10 to 90%, and most preferably 15 to 80%. The dissociation rate may be, for example, 8 to 70%, 15 to 60%, or 30 to 50%, as necessary. When the dissociation rate of the blocked isocyanato group of the structural unit (a-1) is 99% or less, the regeneration of the isocyanato group of the structural unit (a-1) and the occurrence of an unintended crosslinking reaction during the synthesis of the copolymer and during storage of a photosensitive resin composition or photosensitive coloring composition containing the copolymer can be suppressed, thereby ensuring the stability of the copolymer. When the dissociation rate of the blocked isocyanato group of the structural unit (a-1) is 5% or more, good curability can be obtained even when the heating temperature for curing the photosensitive resin composition or photosensitive coloring composition containing the copolymer is sufficiently low, and a cured product with better solvent resistance can be obtained.

[0041] Examples of blocking agents that have an appropriate dissociation rate of the blocked isocyanato group when heated at 100°C for 30 minutes from the viewpoints of the stability of the copolymer and the low-temperature curing properties of the photosensitive resin composition or photosensitive coloring composition include γ-butyrolactam, 1-methoxy-2-propanol, 2,6-dimethylphenol, diisopropylamine, methyl ethyl ketoxime, and 3,5-dimethylpyrazole. Among these blocking agents, 3,5-dimethylpyrazole and methyl ethyl ketoxime are more preferred from the viewpoint of the low-temperature curing properties of the photosensitive resin composition or photosensitive coloring composition containing the copolymer.

[0042] The dissociation rate of the blocked isocyanato group of the structural unit (a-1) having a blocked isocyanato group when heated at 100°C for 30 minutes can be considered to be the same as the dissociation rate of the blocked isocyanato group of the blocked isocyanato group-containing monomer (ma-1) when heated at 100°C for 30 minutes, and is calculated by the method shown below.

[0043] That is, an n-octanol solution having a monomer (ma-1) concentration of 20% by mass is prepared. To the obtained n-octanol solution, 1% by mass of dibutyltin laurate as a catalyst and 3% by mass of phenothiazine as a polymerization inhibitor are added, and the mixture is heated at 100°C for 30 minutes. The n-octanol solution after heating is analyzed by high-performance liquid chromatography (HPLC), and the mass of monomer (ma-1) in the n-octanol solution is determined. Using the results, the mass loss rate of the monomer (ma-1) due to heating at 100°C for 30 minutes is calculated, and this is determined as the dissociation rate when heated at 100°C for 30 minutes.

[0044] The dissociation temperature at which the dissociation rate of the blocked isocyanato groups of the structural unit (a-1) having a blocked isocyanato group reaches 80% or more in 30 minutes is preferably 80°C or higher, more preferably 90°C or higher, and even more preferably 100°C or higher. When the dissociation temperature of the blocked isocyanato groups of the structural unit (a-1) is 80°C or higher, it is possible to prevent the isocyanato groups of the structural unit (a-1) from regenerating and causing an unintended crosslinking reaction during the synthesis of the copolymer and during storage of a photosensitive resin composition or photosensitive coloring composition containing the copolymer, thereby ensuring the stability of the copolymer. The dissociation temperature at which the dissociation rate of the blocked isocyanato groups of the structural unit (a-1) reaches 80% or more in 30 minutes may be 160°C or lower. When the dissociation temperature of the blocked isocyanato group of the structural unit (a-1) is 160°C or less, good curability can be obtained even if the heating temperature for curing the photosensitive resin composition or photosensitive coloring composition containing the copolymer is sufficiently low, and a cured product with even better solvent resistance can be obtained.

[0045] The dissociation temperature at which the dissociation rate of the blocked isocyanato groups of the structural unit (a-1) having a blocked isocyanato group reaches 80% or more in 30 minutes is calculated by the following method. Specifically, an n-octanol solution containing a 20% by mass concentration of monomer (ma-1) is prepared. To the resulting n-octanol solution, 1% by mass of dibutyltin laurate as a catalyst and 3% by mass of phenothiazine as a polymerization inhibitor are added, and the mixture is heated for 30 minutes under multiple temperature conditions. Each of the n-octanol solutions heated under different temperature conditions is analyzed by high-performance liquid chromatography (HPLC), and the mass of monomer (ma-1) in the n-octanol solution is determined. Using the results, the temperature at which the mass loss rate of the monomer (ma-1) after heating for 30 minutes reaches 80% or more is extracted. The lowest temperature among these temperatures is determined as the dissociation temperature at which the dissociation rate of the blocked isocyanato groups reaches 80% or more in 30 minutes.

[0046] Specifically, the structural unit (a-1) having a blocked isocyanato group is preferably at least one selected from a structural unit derived from a compound in which acryloyloxyethyl isocyanate is blocked with 3,5-dimethylpyrazole, as represented by the following formula (4) (dissociation temperature at which the dissociation rate of the blocked isocyanato group becomes 80% or more in 30 minutes: 120°C, dissociation rate when heated at 100°C for 30 minutes: 35%), and a structural unit derived from a compound in which methacryloyloxyethyl isocyanate is blocked with methyl ethyl ketoxime, as represented by the following formula (5) (dissociation temperature at which the dissociation rate of the blocked isocyanato group becomes 80% or more in 30 minutes: 130°C, dissociation rate when heated at 100°C for 30 minutes: 18%).

[0047]

[0048] In one embodiment, the blocking agent is preferably an active methylene compound from the viewpoint of low-temperature curing properties of the photosensitive resin composition or the photosensitive coloring composition.

[0049] In one embodiment, from the viewpoint of low-temperature curing properties of the photosensitive resin composition or photosensitive coloring composition, a compound having an alkyloxycarbonyl group is also preferred as the blocking agent. In this case, the structural unit (a-1) having a blocked isocyanato group has an alkyloxycarbonyl group. By heating the photosensitive resin composition or photosensitive coloring composition containing the copolymer, the alkyloxycarbonyl group undergoes transesterification with the structural unit (a-2) having a hydroxy group to form a crosslinked structure. Therefore, a photosensitive resin composition or photosensitive coloring composition using a copolymer in which the structural unit (a-1) has an alkyloxycarbonyl group can provide a cured film with excellent solvent resistance even when cured at a low temperature of 50°C to 150°C. As the compound having an alkyloxycarbonyl group, an active methylene compound having an alkyloxycarbonyl group is preferred.

[0050] Examples of the structural unit (a-1) in which an active methylene compound having an alkyloxycarbonyl group is used as a blocking agent include structural units having a group represented by the following formula (1) or (2):

[0051] (In formula (1), R １ and R ２ each independently represents an alkyl group having 1 to 10 carbon atoms, and * represents the linking site with the residue remaining after removing the blocked isocyanato group from the structural unit (a-1) having the blocked isocyanato group.

[0052] (In formula (2), R ３ represents an alkyl group having 1 to 10 carbon atoms, and * represents the linking site with the residue remaining after removing the blocked isocyanato group from the structural unit (a-1) having the blocked isocyanato group.

[0053] When the structural unit (a-1) is a structural unit having a group represented by formula (1) or formula (2), when a photosensitive resin composition or photosensitive coloring composition containing the copolymer is cured at a low temperature of 50°C to 150°C, transesterification with the structural unit (a-2) having a hydroxy group occurs, resulting in the formation of a crosslinked structure. Therefore, a photosensitive resin composition or photosensitive coloring composition containing the copolymer can provide a cured film with excellent solvent resistance even when cured at a low temperature of 50°C to 150°C.

[0054] R in the above formula (1) １ and R ２ are each independently an alkyl group having 1 to 10 carbon atoms. １ and R ２ are each independently preferably an alkyl group having 2 to 6 carbon atoms, more preferably an alkyl group having 2 to 3 carbon atoms, and R １ and R ２ Most preferably, both R are ethyl groups. １ and R ２ When R is an ethyl group, when a photosensitive resin composition or a photosensitive coloring composition containing the copolymer is thermally cured, R １ and R ２ is transesterified with the structural unit (a-2) having a hydroxy group to produce ethanol. The ethanol produced during thermal curing of the resin composition is preferred because it is easily evaporated and removed by heating for thermally curing the photosensitive resin composition or photosensitive coloring composition.

[0055] R in the above formula (2) ３ is an alkyl group having 1 to 10 carbon atoms. ３ is preferably an alkyl group having 2 to 6 carbon atoms, more preferably an alkyl group having 2 to 3 carbon atoms, and even more preferably an ethyl group. ３ When R is an ethyl group, when a photosensitive resin composition or a photosensitive coloring composition containing the copolymer is thermally cured, R ３is transesterified with the structural unit (a-2) having a hydroxy group to produce ethanol. The ethanol produced during thermal curing of the resin composition is preferred because it is easily evaporated and removed by heating for thermally curing the photosensitive resin composition or photosensitive coloring composition.

[0056] In this embodiment, the modification rate of the blocked isocyanato group in the structural unit (a-1) having a blocked isocyanato group when heated at 100°C for 30 minutes is assumed to be the same as the modification rate of the blocked isocyanato group in the blocked isocyanato group-containing monomer (ma-1) when heated at 100°C for 30 minutes, and is calculated in the same manner as the dissociation rate calculation method described above. That is, a catalyst and a polymerization inhibitor are added to an n-octanol solution having a monomer (ma-1) concentration of 20% by mass, and the resulting solution is heated at 100°C for 30 minutes to calculate the mass loss of the monomer (ma-1), and this is determined as the modification rate when heated at 100°C for 30 minutes. In the structural unit (a-1) having a blocked isocyanato group, the modification rate of the blocked isocyanato group when heated at 100°C for 30 minutes is preferably 5 to 99%, more preferably 10 to 90%, and most preferably 15 to 80%.

[0057] The content of the structural unit (a-1) in the copolymer precursor can be appropriately determined depending on the application. The content of the structural unit (a-1) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, of all structural units in the copolymer precursor. The content of the structural unit (a-1) is preferably 40 mol% or less, more preferably 30 mol% or less, and even more preferably 25 mol% or less. When the content of the structural unit (a-1) is 5 mol% or more, the low-temperature curing properties of the photosensitive resin composition or photosensitive coloring composition containing the copolymer are good, and the solvent resistance of the cured product is better. When the content of the structural unit (a-1) is 40 mol% or less, the contents of the structural unit (a-2) and the structural unit (a-3) can be sufficiently ensured, and the developability of the photosensitive resin composition or photosensitive coloring composition containing the copolymer is better.

[0058] (Structural Unit (a-2) Having a Hydroxy Group) The structural unit (a-2) having a hydroxy group is a structural unit that does not have a blocked isocyanato group. The structural unit (a-2) may be of only one type, or may be of two or more types. The structural unit (a-2) is a structural unit derived from a hydroxy group-containing monomer (ma-2) (hereinafter, also simply referred to as "monomer (ma-2)"). By having the structural unit (a-2) in the copolymer, crosslinking with the structural unit (a-1) having a blocked isocyanato group progresses when the photosensitive resin composition or photosensitive coloring composition is heated. As a result, the obtained cured product has good solvent resistance even under low-temperature curing conditions.

[0059] From the viewpoint of low-temperature curing properties, the structural unit (a-2) is preferably a —CH ２ A structural unit having a group represented by —OH is preferred, and —(CH ２ ) ｎ A structural unit having a group represented by —OH (n is an integer of 2 to 6) and —(O—C ｘ H ２ｘ ) ｍ It is more preferable that the structural unit is at least one selected from the group consisting of structural units having a group represented by —OH (where x is an integer of 2 to 4, and m is an integer of 2 to 6).

[0060] Examples of the monomer (ma-2) include a compound having an ethylenically unsaturated bond and a hydroxy group without a blocked isocyanato group. Examples of the ethylenically unsaturated group contained in the monomer (ma-2) include a vinyl group and a (meth)acryloyloxy group.

[0061] Examples of the monomer (ma-2) include compounds having a hydroxy group and a (meth)acryloyloxy group, and specific examples thereof include hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-(2-hydroxyethoxy)ethyl (meth)acrylate, 2-[2-[2-(2-hydroxyethoxy)ethoxy]ethoxy]ethyl (meth)acrylate, hexaethylene glycol mono(meth)acrylate, and octaethylene glycol mono(meth)acrylate. The monomer (ma-2) may be used alone or in combination of two or more.

[0062] Among the above monomers, hydroxyalkyl(meth)acrylates are preferred as the monomer (ma-2) from the viewpoints of reactivity during synthesis of the copolymer precursor, low-temperature curing properties of the photosensitive resin composition or photosensitive coloring composition containing the copolymer, and ease of availability. Preferred hydroxyalkyl(meth)acrylates are 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 2,3-dihydroxypropyl(meth)acrylate, and 4-hydroxybutyl(meth)acrylate, and from the viewpoint of reducing the glass transition temperature of the copolymer, 2-hydroxyethyl(meth)acrylate and 4-hydroxybutyl(meth)acrylate are more preferred.

[0063] The content of the structural unit (a-2) is preferably 1 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on all structural units of the copolymer precursor. The content of the structural unit (a-2) is preferably 35 mol% or less, more preferably 25 mol% or less, and even more preferably 20 mol% or less, based on all structural units of the copolymer precursor. When the content of the structural unit (a-2) is 1 mol% or more, a sufficient amount of crosslinking with the blocked isocyanato group of the structural unit (a-1) can be ensured, and the low-temperature curing properties of the photosensitive resin composition or photosensitive coloring composition containing the copolymer are good. When the content of the structural unit (a-2) is 35 mol% or less, the content of the structural unit (a-1) can be sufficiently ensured, and the low-temperature curing properties of the photosensitive resin composition or photosensitive coloring composition containing the copolymer are good, and the solvent resistance of the cured product is even better. Furthermore, the content of the structural unit (a-3) can be sufficiently ensured, and the developability of the photosensitive resin composition or photosensitive coloring composition containing the copolymer is even better.

[0064] (Structural Unit (a-3) Having an Acid Group) The structural unit (a-3) having an acid group is not particularly limited, as long as it is a structural unit that does not have a blocked isocyanato group or a hydroxy group and has an acid group. The structural unit (a-3) may be of only one type, or of two or more types. The structural unit (a-3) is a structural unit derived from an acid group-containing monomer (ma-3) (hereinafter, also simply referred to as "monomer (ma-3)"). By having the structural unit (a-3) in the copolymer, a photosensitive resin composition or photosensitive coloring composition containing the copolymer will have good developability.

[0065] Examples of the acid group contained in the structural unit (a-3) include a carboxy group, a sulfo group, a phospho group, etc. Of these acid groups, a carboxy group is preferred as the acid group contained in the structural unit (a-3) from the standpoint of ease of availability.

[0066] Examples of the monomer (ma-3) include a monomer that does not have a blocked isocyanato group or a hydroxy group, but has an ethylenically unsaturated bond and an acid group, such as an unsaturated carboxylic acid or an anhydride thereof, an unsaturated sulfonic acid, or an unsaturated phosphonic acid.

[0067] Specific examples of the monomer (ma-3) include unsaturated carboxylic acids or anhydrides thereof such as (meth)acrylic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl succinic acid, α-bromo(meth)acrylic acid, β-furyl(meth)acrylic acid, 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-acrylamido-2-methylpropanesulfonic acid, tert-butylacrylamidosulfonic acid, and p-styrenesulfonic acid; and unsaturated phosphonic acids such as vinylphosphonic acid. Monomer (ma-3) may be used alone or in combination of two or more.

[0068] Among these monomers, it is preferable to use an unsaturated carboxylic acid as the monomer (ma-3), and it is more preferable to use (meth)acrylic acid, because it is easily available and the photosensitive resin composition or photosensitive coloring composition containing the copolymer will have better alkaline developability.

[0069] The content of the structural unit (a-3) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, of all structural units of the copolymer precursor. The content of the structural unit (a-3) is preferably 70 mol% or less, more preferably 65 mol% or less, and even more preferably 60 mol% or less, of all structural units of the copolymer precursor. When the content of the structural unit (a-3) is 5 mol% or more, the developability of a photosensitive resin composition or photosensitive coloring composition containing the copolymer is better. When the content of the structural unit (a-3) is 70 mol% or less, the contents of the structural unit (a-1) and the structural unit (a-2) can be sufficiently ensured, and the low-temperature curing properties of the photosensitive resin composition or photosensitive coloring composition containing the copolymer are good, and the solvent resistance of the cured product is better.

[0070] (Other Structural Unit (a-4)) The copolymer precursor may, if necessary, have a structural unit (a-4) other than the structural units (a-1) to (a-3). The other structural unit (a-4) is a structural unit derived from another monomer (ma-4) (hereinafter also simply referred to as "monomer (ma-4)") that does not have a blocked isocyanato group, a hydroxy group, or an acid group, and is copolymerizable with the monomers (ma-1) to (ma-3). The structural unit (a-4) makes it possible to adjust the physical properties required for the copolymer or to impart functions to the copolymer.

[0071] Specific examples of the monomer (ma-4) include aromatic vinyl compounds, cyclic olefins having a norbornene structure, dienes, (meth)acrylic acid esters, (meth)acrylic acid amides, vinyl compounds, unsaturated dicarboxylic acid diesters, monomaleimides, glycidyl (meth)acrylate, (meth)acrylic acid anilide, (meth)acrylonitrile, and acrolein.

[0072] Examples of aromatic vinyl compounds include styrene, α-methylstyrene, o-vinyltoluene, p-vinyltoluene, o-chlorostyrene, m-chlorostyrene, methoxystyrene, p-nitrostyrene, p-cyanostyrene, p-acetylaminostyrene, and vinylpyridine.

[0073] Examples of cyclic olefins having a norbornene structure include norbornene (bicyclo[2.2.1]hept-2-ene), 5-methylbicyclo[2.2.1]hept-2-ene, and tetracyclo[4.4.0.1]hept-2-ene. 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-ethylidenetetracyclo[4.4.0.1 ２，５ .1 ７，１２ ] dodec-3-ene, pentacyclo[6.5.1.1 ３，６ .0 ２，７ .0 ９，１３ ]pentadec-4-ene, and the like.

[0074] Examples of dienes include butadiene, isoprene, and chloroprene.

[0075] Examples of (meth)acrylic acid esters include methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, benzyl (meth)acrylate, isoamyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate, cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, rosin (meth)acrylate, norbornyl (meth)acrylate, 5-ethylnorbornyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyloxyethyl acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, and tricyclodecanyl (meth)acrylate. n-propyl (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, cumyl (meth)acrylate, 4-phenoxyphenyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, nonylphenoxypolyethylene glycol mono(meth)acrylate, biphenyloxyethyl (meth)acrylate, naphthalene (meth)acrylate, anthracene (meth)acrylate, and ethoxylated phenyl (meth)acrylate.

[0076] Examples of the (meth)acrylic acid amide include (meth)acrylic acid amide, (meth)acrylic acid N,N-dimethylamide, (meth)acrylic acid N,N-diisopropylamide, and (meth)acrylic acid anthracenylamide.

[0077] Examples of the vinyl compound include vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, N-vinylpyrrolidone, and vinyl acetate.

[0078] Examples of the unsaturated dicarboxylic acid diester include diethyl citraconate, diethyl maleate, diethyl fumarate, and diethyl itaconate.

[0079] Examples of monomaleimides include N-phenylmaleimide, N-cyclohexylmaleimide, and N-laurylmaleimide.

[0080] The monomer (ma-4) may be used alone or in combination of two or more kinds.

[0081] When the copolymer precursor contains the structural unit (a-4), the content of the structural unit (a-4) is preferably 1 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, based on all structural units of the copolymer precursor. The content of the structural unit (a-4) is preferably 70 mol% or less, more preferably 60 mol% or less, and even more preferably 50 mol% or less, based on all structural units of the copolymer precursor. When the content of the structural unit (a-4) is 1 mol% or more, the necessary functions can be imparted to the copolymer. When the content of the structural unit (a-4) is 70 mol% or less, the contents of the structural units (a-1) to (a-3) can be sufficiently ensured, so that the developability and low-temperature curability of the photosensitive resin composition or photosensitive coloring composition containing the copolymer are better, and the solvent resistance of the cured product is better.

[0082] (Ethylenically unsaturated compound (e) having a functional group reactive with an acid group) The compound (e) has a functional group reactive with an acid group and an ethylenically unsaturated group. The compound (e) may be of only one type, or of two or more types. By adding the compound (e) to a copolymer precursor, an ethylenically unsaturated group is introduced. As a result, a photosensitive resin composition or a photosensitive coloring composition containing the copolymer has good photocurability, and the solvent resistance of the cured product is improved.

[0083] Examples of functional groups reactive with acid groups include epoxy groups, oxetanyl groups, hydroxy groups, isocyanato groups, etc. Among these, epoxy groups are preferred from the viewpoint of ease of synthesis of the copolymer.

[0084] Examples of the ethylenically unsaturated compound having an epoxy group include (meth)acrylic acid ester derivatives containing an epoxy group, such as oxiranyl(meth)acrylate, glycidyl(meth)acrylate, 2-methylglycidyl(meth)acrylate, 2-ethylglycidyl(meth)acrylate, 2-oxiranylethyl(meth)acrylate, 2-glycidyloxyethyl(meth)acrylate, 3-glycidyloxypropyl(meth)acrylate, 4-glycidyloxybutyl(meth)acrylate, and glycidyloxyphenyl(meth)acrylate; and 3,4-epoxycyclohexyl(meth)acrylate. ) acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, 2-(3,4-epoxycyclohexyl)ethyl (meth)acrylate, 2-(3,4-epoxycyclohexylmethyloxy)ethyl (meth)acrylate, 3-(3,4-epoxycyclohexylmethyloxy)propyl (meth)acrylate, and other (meth)acrylate derivatives containing an epoxy group-containing alicyclic carbon ring such as a 3,4-epoxycyclohexane ring; vinyl ether compounds containing an epoxy group; and allyl ether compounds containing an epoxy group. Among these, from the viewpoints of polymerizability and ease of availability, epoxy group-containing (meth)acrylates such as oxiranyl (meth)acrylate, glycidyl (meth)acrylate, 2-methylglycidyl (meth)acrylate, 2-ethylglycidyl (meth)acrylate, 2-oxiranylethyl (meth)acrylate, 2-glycidyloxyethyl (meth)acrylate, 4-glycidyloxybutyl (meth)acrylate, glycidyloxyphenyl (meth)acrylate, and 3,4-epoxycyclohexylmethyl (meth)acrylate are preferred, with glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, and 4-glycidyloxybutyl (meth)acrylate being more preferred.

[0085] The compound (e) may be used alone or in combination of two or more kinds.

[0086] The amount of compound (e) added is preferably 1 mole or more, more preferably 3 moles or more, and even more preferably 5 moles or more, relative to 100 moles of the structural units of the copolymer precursor. The amount of compound (e) added is preferably 55 moles or less, more preferably 45 moles or less, and even more preferably 35 moles or less, relative to 100 moles of the structural units of the copolymer precursor. When the amount of compound (e) added relative to 100 moles of the structural units of the copolymer precursor is 1 mole or more, the photocurability of the photosensitive resin composition or photosensitive coloring composition containing the copolymer is good. When the amount of compound (e) added relative to 100 moles of the structural units of the copolymer precursor is 55 moles or less, the acid group content of the structural unit (a-3) can be sufficiently ensured, and the developability of the photosensitive resin composition or photosensitive coloring composition containing the copolymer is better.

[0087] The amount of compound (e) added is preferably 1 mole or more, more preferably 5 moles or more, and even more preferably 10 moles or more, per 100 moles of the structural unit (a-3) of the copolymer precursor. The amount of compound (e) added is preferably 85 moles or less, more preferably 75 moles or less, and even more preferably 65 moles or less, per 100 moles of the structural unit (a-3) of the copolymer precursor. When the amount of compound (e) added per 100 moles of structural unit (a-3) is 1 mole or more, the photocurability of the photosensitive resin composition or photosensitive coloring composition containing the copolymer is good. When the amount of compound (e) added per 100 moles of structural unit (a-3) is 85 moles or less, the acid group content of the structural unit (a-3) can be sufficiently ensured, and the developability of the photosensitive resin composition or photosensitive coloring composition containing the copolymer is better.

[0088] <Method for Producing Copolymer> The copolymer can be produced by a method including the steps of copolymerizing a blocked isocyanato group-containing monomer (ma-1), a hydroxy group-containing monomer (ma-2), an acid group-containing monomer (ma-3), and, if necessary, other monomers (ma-4) to obtain a copolymer precursor, and adding compound (e) to a portion of the acid groups of structural unit (a-3) of the copolymer precursor to obtain a copolymer. The proportions of structural unit (a-1), structural unit (a-2), structural unit (a-3), and structural unit (a-4) contained in the copolymer precursor are the same as the proportions of each of monomer (ma-1), monomer (ma-2), monomer (ma-3), and monomer (ma-4) in the total of all monomers used as raw materials for the copolymer precursor.

[0089] The proportions of the monomers used in the copolymerization reaction to form the copolymer precursor are not particularly limited. Preferably, the proportions are 5 to 40 mol% of the monomer (ma-1), 1 to 35 mol% of the monomer (ma-2), and 5 to 70 mol% of the monomer (ma-3), more preferably 10 to 30 mol% of the monomer (ma-1), 5 to 25 mol% of the monomer (ma-2), and 10 to 65 mol% of the monomer (ma-3), and even more preferably 15 to 25 mol% of the monomer (ma-1), 10 to 20 mol% of the monomer (ma-2), and 15 to 60 mol% of the monomer (ma-3). When other monomer (ma-4) is further used, preferably, monomer (ma-1) is 5 to 40 mol%, monomer (ma-2) is 1 to 35 mol%, monomer (ma-3) is 5 to 70 mol%, and monomer (ma-4) is 1 to 70 mol%, more preferably, monomer (ma-1) is 10 to 30 mol%, monomer (ma-2) is 5 to 25 mol%, monomer (ma-3) is 10 to 65 mol%, and monomer (ma-4) is 5 to 60 mol%, and even more preferably, monomer (ma-1) is 15 to 25 mol%, monomer (ma-2) is 10 to 20 mol%, monomer (ma-3) is 15 to 60 mol%, and monomer (ma-4) is 10 to 50 mol%.

[0090] The copolymerization reaction can be carried out in the presence or absence of a solvent according to a radical polymerization method known in the art. For example, the above-mentioned monomers may be dissolved in an organic solvent, a polymerization initiator may be added to the solution, and the polymerization reaction may be carried out at 50 to 100°C for 1 to 20 hours. In this case, if the polymerization reaction is carried out at a temperature at which the blocked isocyanato group of the blocked isocyanato group-containing monomer (ma-1) dissociates, the isocyanato group generated by dissociation of the blocked isocyanato group may react with the acid group of the monomer (ma-3) to form a gel. Therefore, it is preferable to carry out the polymerization at a temperature below the dissociation temperature of the blocked isocyanato group, preferably at a temperature about 20 to 50°C below the dissociation temperature of the blocked isocyanato group.

[0091] The solvent used in the copolymerization reaction can be the same as the solvent (D) described below. Other examples include hydroxyl group-containing organic solvents such as propylene glycol monoaryl ether, 1,3-propanediol monoalkyl ether, 1,3-butanediol monoalkyl ether, 1,4-butanediol monoalkyl ether, glycerin monoalkyl ether, glycerin dialkyl ether, methanol, ethanol, propanol, C5-6 cycloalkanediol, C5-6 cycloalkane dimethanol, ethyl lactate, and diacetone alcohol. Note that "C5-6 cycloalkane" refers to a cycloalkyl group having 5 to 6 carbon atoms. From the viewpoint of preventing abnormal polymerization and ensuring stable polymerization, the copolymerization reaction is preferably carried out in the presence of a hydroxyl group-containing organic solvent. By carrying out the copolymerization reaction in the presence of a hydroxyl group-containing organic solvent, even if a blocked isocyanato group dissociates to generate an isocyanato group, the isocyanato group reacts with the hydroxyl group of the hydroxyl group-containing organic solvent, preventing abnormal polymerization. In the copolymer precursor obtained in this manner, it is believed that a portion of the blocking agent that blocked the isocyanato groups has been substituted with the hydroxy group-containing organic solvent. The solvent may be used alone or in combination of two or more.

[0092] The polymerization initiator that can be used in the copolymerization reaction is not particularly limited, but examples thereof include azobisisobutyronitrile, azobisisovaleronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, and t-butylperoxy-2-ethylhexanoate. The polymerization initiators may be used alone or in combination of two or more. The amount of the polymerization initiator used is generally 0.5 to 20 parts by mass, and preferably 1.0 to 18 parts by mass, per 100 parts by mass of the total amount of monomers charged.

[0093] A known addition reaction can be used as a method for adding compound (e) to a portion of the acid groups of the structural unit (a-3) of the copolymer precursor. For example, a polymerization inhibitor and a catalyst are added to a reaction solution in which a copolymerization reaction has been carried out, and then compound (e) is added, and the addition reaction is carried out under conditions of room temperature (23°C) to 150°C, preferably 50 to 120°C. The polymerization inhibitor is added to prevent side reactions of the introduced unsaturated groups.

[0094] Specific examples of the polymerization inhibitor include hydroquinone, methylhydroquinone, hydroquinone monomethyl ether, and dibutylhydroxytoluene.

[0095] Specific examples of the catalyst include quaternary ammonium salts such as triethylbenzylammonium chloride; phosphorus compounds such as triphenylphosphine, tris(2,6-dimethoxyphenyl)phosphine, tripartylphosphine, tricyclohexylphosphine, and tetraphenylphosphonium salts; and organometallic compounds containing metals such as chromium and tin. The amount of the catalyst used is preferably 0.5 to 12 parts by mass, and more preferably 1.0 to 6.0 parts by mass, per 100 parts by mass of the total of the monomers and compound (e) used in the copolymerization reaction of the copolymer precursor.

[0096] Specific examples of the catalyst include the following basic catalyst (X) from the viewpoint of reactivity: The basic catalyst (X) may be used alone or in combination of two or more kinds.

[0097] As the basic catalyst (X), one having a pKa (acidity constant; also referred to as acid dissociation constant) at 25°C of 4 to 15 is preferably used. Basic catalysts having a pKa of 4 or more at 25°C include those having a pKa of 4 or more in aqueous solution, and those that are too acidic to be measured in aqueous solution and have a pKa of 4 or more in aqueous solution converted from the results of measurement in an organic solvent. The pKa of the basic catalyst (X) at 25°C may be 15 or less, 13 or less, or 11 or less. The pKa of the basic catalyst (X) at 25°C may be 4 or more, 5 or more, 6 or more, or 7 or more. When the pKa of the basic catalyst (X) at 25°C is 15 or less, it is possible to suppress a decrease in activity due to the formation of a salt with the acid group possessed by the structural unit (a-3).

[0098] Examples of the basic catalyst (X) include compounds represented by the following formula (6): ９ N=CR １０ -NR １１ R １２ ...(6) (In formula (6), R ９ , R １１ and R １２ are each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and R １０ represents a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or —N(R １３ ) ２ A group represented by the formula (R １３ is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and two R １３ may be the same or different from each other, and R ９ , R １０ , R １１ , R １２ and two R １３ Any two or more of the groups may be bonded to form a cyclic structure.

[0099] The basic catalyst (X) also includes, for example, a compound represented by formula (7): １４ N=CR １５ -NR １６ R １７...(7) (In formula (7), R １４ , R １５ , R １６ and R １７ is a hydrocarbon group, and R １４ and R １７ and form a ring structure, and R １４ and R １７ The sum of the carbon atoms of R is 3 to 20, １５ and R １６ and form a ring structure, and R １５ and R １６ The sum of the carbon atoms is 3 to 20.)

[0100] In the compound represented by formula (7), R forming a cyclic structure １４ and R １７ The sum of the carbon atoms of the groups is 3 to 20, and from the viewpoint of availability, it is preferably 3 to 10.

[0101] In the compound represented by formula (7), R forming a cyclic structure １５ and R １６ The sum of the carbon atoms of the groups is 3 to 20, and from the viewpoint of availability, it is preferably 3 to 10.

[0102] Specific examples of the compound represented by formula (6) or formula (7) include 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 viewpoints of catalytic activity strength, compatibility with solvents, ease of availability, etc., it is preferable to use 1,8-diazabicyclo[5.4.0]-7-undecene.

[0103] Examples of the basic catalyst (X) include alkylamines and cyclic diamines.

[0104] Examples of alkylamines include diisopropylamine (pKa 11.05), trimethylamine, and triethylamine (pKa 10.7).

[0105] Examples of cyclic diamines include 1,4-diazabicyclo[2.2.2]octane (DABCO) (pKa 8.8).

[0106] From the viewpoint of efficiently proceeding with the addition reaction of compound (e), the basic catalyst (X) is preferably at least one selected from the group consisting of pyridine, pyridine derivatives, and imidazole compounds. A pyridine derivative is a compound in which a hydrogen atom of pyridine is substituted with one or more substituents. Without being bound by any theory, pyridine, pyridine derivatives, and imidazole compounds have a relatively low pKa and therefore maintain activity without forming a salt with the acid group of the structural unit (a-3), and also have high nucleophilicity due to resonance stabilization. Therefore, by using at least one selected from the group consisting of pyridine, pyridine derivatives, and imidazole compounds, the addition reaction of compound (e) can be efficiently proceeded and an ethylenically unsaturated group can be introduced.

[0107] Specific examples of pyridine and pyridine derivatives include pyridine (pKa 5.2); C1-4 alkylpyridines such as methylpyridine (picoline) (pKa 6.75) and ethylpyridine; di-C1-4 alkylpyridines such as dimethylpyridine (lutidine) (pKa 6.47 to 6.6); tri-C1-4 alkylpyridines such as trimethylpyridine (collidine) (pKa 7.48); and 4-aminopyridine derivatives having an amino group at the 4-position such as 4-aminopyridine (pKa 9.17), 4-dimethylaminopyridine (pKa 9.7), 4-diethylaminopyridine, 4-pyrrolidinopyridine, 4-piperidinopyridine, and 2-methyl-4-dimethylaminopyridine. Among these, from the viewpoint of reactivity, 4-aminopyridine derivatives are preferred, 4-aminopyridine derivatives having a tertiary amino group at the 4-position are more preferred, 4-dialkylaminopyridines are even more preferred, and 4-dimethylaminopyridine is particularly preferred. Incidentally, "C1-4 alkyl" means that the alkyl group has 1 to 4 carbon atoms.

[0108] Examples of the imidazole compound include 2-methylimidazole (pKa 7.75) and 1,2-dimethylimidazole (pKa 7.8).

[0109] The content of the basic catalyst (X) is preferably 0.5 parts by mass or more, more preferably 0.7 parts by mass or more, and even more preferably 1.0 parts by mass or more, relative to 100 parts by mass of the total of the monomers and compound (e) used in the copolymerization reaction of the copolymer precursor. The content of the basic catalyst (X) is preferably 12 parts by mass or less, more preferably 9.0 parts by mass or less, and even more preferably 6.0 parts by mass or less, relative to 100 parts by mass of the total of the monomers and compound (e) used in the copolymerization reaction of the copolymer precursor. When the content of the basic catalyst (X) is 0.5 parts by mass or more, the reaction rate when adding compound (e) is high, which is preferable. When the content of the basic catalyst (X) is 12 parts by mass or less, even when the photosensitive resin composition or photosensitive coloring composition is produced using the reaction solution used in producing the copolymer as is, the effect of the basic catalyst (X) can be suppressed when curing the photosensitive resin composition or photosensitive coloring composition.

[0110] <Photosensitive Resin Composition> 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 resin composition can be polymerized and cured by light irradiation to form a cured resin film.

[0111] The copolymer of the present disclosure can be used as the copolymer (A).

[0112] The content of copolymer (A) in the photosensitive resin composition or photosensitive coloring composition is preferably 10% by mass or more, more preferably 25% by mass or more, and even more preferably 40% by mass or more, based on the total of copolymer (A) and reactive diluent (B). The content of copolymer (A) is preferably 90% by mass or less, more preferably 75% by mass or less, and even more preferably 60% by mass or less, based on the total of copolymer (A) and reactive diluent (B). When the content of copolymer (A) is within the above range, the viscosity of the photosensitive resin composition or photosensitive coloring composition becomes a range suitable for handling, and in addition, the photocurability is also improved.

[0113] [Reactive Diluent (B)] The reactive diluent (B) is not particularly limited as long as it is a low-molecular-weight compound having at least one ethylenically unsaturated group. In this specification, a low-molecular-weight compound refers to a compound having a molecular weight of less than 1,000. Examples of the ethylenically unsaturated group include a vinyl group, an allyl group, and a (meth)acryloyloxy group. From the viewpoint of improving curing properties, a polyfunctional reactive diluent having multiple ethylenically unsaturated groups is preferred. Specific examples of the reactive diluent (B) include aromatic vinyl compounds; aromatic allyl compounds such as diallyl phthalate and diallyl benzene phosphonate; vinyl carboxylates such as vinyl acetate and vinyl adipate; monofunctional (meth)acrylates; polyfunctional (meth)acrylates; triallyl cyanurate, etc.

[0114] Specific examples of aromatic vinyl compounds include styrene, α-methylstyrene, α-chloromethylstyrene, vinyltoluene, and divinylbenzene.

[0115] Specific examples of monofunctional (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, β-hydroxyethyl (meth)acrylate, and hydroxypropyl (meth)acrylate.

[0116] Specific examples of polyfunctional (meth)acrylates include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and tris(hydroxyethyl)isocyanurate tri(meth)acrylate.

[0117] Among these, polyfunctional (meth)acrylates are preferred as the reactive diluent (B) in order to improve reactivity, and at least one selected from dipentaerythritol penta(meth)acrylate and dipentaerythritol hexa(meth)acrylate is particularly preferred.

[0118] The reactive diluent (B) may be used alone or in combination of two or more kinds.

[0119] The content of the reactive diluent (B) in the photosensitive resin composition or the photosensitive coloring composition is preferably 10% by mass or more, more preferably 25% by mass or more, and even more preferably 40% by mass or more, based on the total of the copolymer (A) and the reactive diluent (B). The content of the reactive diluent (B) is preferably 90% by mass or less, more preferably 75% by mass or less, and even more preferably 60% by mass or less, based on the total of the copolymer (A) and the reactive diluent (B). When the content of the reactive diluent (B) is within the above range, the viscosity of the photosensitive resin composition or the photosensitive coloring composition becomes a range suitable for handling, and in addition, the photocurability is also improved.

[0120] [Photopolymerization initiator (C)] The photopolymerization initiator (C) is not particularly limited, and examples thereof include 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl-]-,-1-(O-acetyloxime); 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-t-butyldioxy-1-methylethyl)acetophenone; 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one; 2-benzyl-2-dimethylamino-1-(4-morpholino) Examples of the photopolymerization initiator (C) include anthraquinone compounds such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone, and 1-chloroanthraquinone; xanthone; thioxanthone compounds such as thioxanthone, 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorothioxanthone; ketal compounds such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenone compounds such as 4-(1-t-butyldioxy-1-methylethyl)benzophenone and 3,3',4,4'-tetrakis(t-butyldioxycarbonyl)benzophenone; and acylphosphine oxide photopolymerization initiators. The photopolymerization initiator (C) may be used alone or in combination of two or more.

[0121] The content of the photopolymerization initiator (C) in the photosensitive resin composition or photosensitive coloring composition is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 1.0 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 photopolymerization initiator (C) in the photosensitive resin composition or photosensitive coloring composition is preferably 30 parts by mass or less, more preferably 15 parts by mass or less, and even 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). When the content of the photopolymerization initiator (C) is 0.1 parts by mass or more, a photosensitive resin composition or photosensitive coloring composition with good photocurability can be obtained. 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 photosensitive coloring composition from being adversely affected by too much photopolymerization initiator (C).

[0122] [Solvent (D)] Examples of the solvent (D) include ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, diethylene glycol monoalkyl ethers such as diethylene glycol monomethyl ether and diethylene glycol mono-n-butyl ether, propylene glycol monoalkyl ethers such as triethylene glycol monomethyl ether, propylene glycol monomethyl ether and propylene glycol monoethyl ether, dipropylene glycol monoalkyl ethers such as dipropylene glycol monomethyl ether, tripropylene glycol monoalkyl ethers such as tripropylene glycol monoethyl ether, (poly)alkylene glycol monoalkyl ethers such as 3-methoxy-1-butanol, hydroxy group-containing carboxylic acid esters such as methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl hydroxyacetate, and methyl 2-hydroxy-3-methylbutyrate, and diethylene glycol hydroxy group-containing organic solvents such as ethanol; 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 diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, and tetrahydrofuran; methyl ethyl ketone, cyclohexanone, Ketones such as 2-heptanone and 3-heptanone; esters such as methyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl ethoxyacetate, 3-methyl-3-methoxybutyl acetate, 3-methyl-3-methoxybutylpropionate, ethyl acetate, n-butyl acetate, i-propyl acetate, i-butyl acetate, n-amyl acetate, i-amyl acetate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, i-propyl butyrate, ethyl pyruvate, n-propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, and ethyl 2-oxobutyrate;Examples of the solvent (D) include aromatic hydrocarbons such as toluene and xylene, and hydroxy-free organic solvents such as carboxylic acid amides such as N-methylpyrrolidone, N,N-dimethylformamide and N,N-dimethylacetamide. The solvent (D) may be used alone or in combination of two or more.

[0123] Among these solvents (D), from the viewpoints of availability, cost, and stability during resist preparation, it is preferable to use a compound having an ether structure, and specifically, it is more preferable to use at least one 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.

[0124] The content of the solvent (D) in the photosensitive resin composition or the photosensitive coloring composition is preferably 30 parts by mass or more, more preferably 50 parts by mass or more, relative to 100 parts by mass of the total of the components excluding the solvent (D). 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, more preferably 800 parts by mass or less, relative to 100 parts by mass of the total of the components excluding the solvent (D). 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, when removing the solvent (D) in the coating film formed by applying the photosensitive resin composition or the photosensitive coloring composition to a substrate, the solvent (D) can be easily removed.

[0125] <Photosensitive Coloring Composition> The photosensitive coloring composition contains a colorant (E) in addition to the above-mentioned photosensitive resin composition.

[0126] [Colorant (E)] The photosensitive coloring composition containing the colorant (E) can be used as a material for a color filter.

[0127] The colorant (E) is not particularly limited as long as it is soluble or dispersible in the solvent (D), and examples thereof include dyes and pigments.

[0128] As the dye, from the viewpoint of solubility in the solvent (D) and the alkaline developer, interaction with other components in the photosensitive coloring composition, heat resistance, etc., it is preferable to use an acid dye having an acid group such as a carboxy group or a sulfo group, a salt of an acid dye with a nitrogen compound, a sulfonamide adduct of an acid dye, etc.

[0129] 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; and acid 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 6B, 7, 9, 17, 19; 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 derivatives thereof. Among these, azo-based, xanthene-based, anthraquinone-based, or phthalocyanine-based acid dyes are preferred. The dyes may be used alone or in combination of two or more.

[0130] Examples of pigments include yellow pigments such as C.I. Pigment Yellow 1, 3, 12, 13, 14, 15, 16, 17, 20, 24, 31, 53, 83, 86, 93, 94, 109, 110, 117, 125, 128, 137, 138, 139, 147, 148, 150, 153, 154, 166, 173, 194, and 214; orange pigments such as C.I. Pigment Orange 13, 31, 36, 38, 40, 42, 43, 51, 55, 59, 61, 64, 65, 71, and 73; Examples of suitable pigments include red pigments such as C.I. Pigment Red 9, 97, 105, 122, 123, 144, 149, 166, 168, 176, 177, 180, 192, 209, 215, 216, 224, 242, 254, 255, 264, and 265; blue pigments such as C.I. Pigment Blue 15, 15:3, 15:4, 15:6, and 60; violet pigments such as C.I. Pigment Violet 1, 19, 23, 29, 32, 36, and 38; green pigments such as C.I. Pigment Green 7, 36, 58, and 59; brown pigments such as C.I. Pigment Brown 23 and 25; and black pigments such as C.I. Pigment Black 1 and 7, carbon black, titanium black, and iron oxide. The pigments may be used alone or in combination of two or more kinds.

[0131] The colorant (E) can be appropriately determined depending on, for example, the desired color pattern, i.e., the color of the black matrix and pixels. The colorant (E) may be used alone or in combination of two or more. When two or more types of colorants (E) are used, a dye and a pigment may be used in combination.

[0132] When a pigment is used as the colorant (E), a known dispersant may be blended into the photosensitive coloring composition to improve the dispersibility of the pigment. It is preferable to use a polymer dispersant that has excellent dispersion stability over time. Examples of polymer dispersants include urethane-based dispersants, polyethyleneimine-based dispersants, polyoxyethylene alkyl ether-based dispersants, polyoxyethylene glycol diester-based dispersants, sorbitan aliphatic ester-based dispersants, and aliphatic modified ester-based dispersants. Commercially available polymer dispersants under trade names such as EFKA (EFKA CHEMICALS B.V.), Disperbyk (BYK), Disparlon (Kusumoto Chemicals Co., Ltd.), and SOLSPERSE (Lubrizol Corporation) may also be used. The content of the dispersant may be appropriately determined depending on the type and amount of the pigment used as the colorant (E).

[0133] The content of the colorant (E) in the photosensitive coloring composition is preferably 0.1 parts by mass or more, more preferably 5 parts by mass or more, and even more preferably 10 parts by mass or more, relative to the total 100 parts by mass 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 even more preferably 60 parts by mass or less, relative to the total 100 parts by mass of the copolymer (A) and the reactive diluent (B). When the content of the colorant (E) is 0.1 parts by mass or more, the effect of containing the colorant (E) becomes significant, and a photosensitive coloring composition suitable as a material for the color pattern of a color filter can be obtained. When the content of the colorant (E) is 80 parts by mass or less, the colorant (E) does not interfere with the curing property of the photosensitive coloring composition, and a photosensitive coloring composition with good low-temperature curing property can be obtained.

[0134] [Other Components] In one embodiment, the photosensitive resin composition or photosensitive coloring composition may contain, in addition to the copolymer (A), the reactive diluent (B), the photopolymerization initiator (C), the solvent (D), and the coloring agent (E) contained as needed, known additives such as coupling agents, leveling agents, polymerization inhibitors, etc. The amount of the additives to be added may be within a range that does not inhibit the effects of the present invention, and is not particularly limited.

[0135] <Method for producing photosensitive resin composition and photosensitive coloring composition> The photosensitive resin composition of one embodiment can be produced by a method of 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 a method of mixing the copolymer (A), the reactive diluent (B), the photopolymerization initiator (C), the solvent (D), and the colorant (E) using a known mixing device.

[0136] When producing a photosensitive resin composition or a photosensitive coloring composition, the reaction solution used in producing the copolymer (A) can be used as it is as a raw material. In this case, the solvent contained in the reaction solution can be used as part or all of the solvent (D) contained in the photosensitive resin composition or the photosensitive coloring composition.

[0137] When producing a photosensitive resin composition or a photosensitive coloring composition, the copolymer (A) isolated by a known method from a reaction solution containing the copolymer (A) may be used as a raw material.

[0138] The photosensitive resin composition or the photosensitive coloring composition contains the copolymer (A) having an ethylenically unsaturated group introduced by the addition of the compound (e), the reactive diluent (B), and the photopolymerization initiator (C), and therefore, upon irradiation with light, the reactive diluent (B) polymerizes together with the ethylenically unsaturated group contained in the copolymer (A), thereby exhibiting good photocurability.

[0139] Furthermore, the photosensitive resin composition or photosensitive coloring composition has good low-temperature curing properties because it contains a copolymer (A) containing a structural unit (a-1) having a blocked isocyanato group and a structural unit (a-2) having a hydroxy group.

[0140] For these reasons, when a cured product is formed using a photosensitive resin composition or a photosensitive coloring composition, it can be cured at a lower temperature than when a conventional resin composition is used. Therefore, when a baking treatment is performed after exposing a coating film formed on a substrate, for example, the photosensitive resin composition or the photosensitive coloring composition can form a cured product having excellent solvent resistance because the crosslinking reaction proceeds sufficiently even if the baking temperature is low.

[0141] Therefore, when a cured product is formed using a photosensitive resin composition or a photosensitive coloring composition, less energy is required for heating to cure. 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 causing any damage to the substrate. Furthermore, with regard to the photosensitive coloring composition, even when a colorant (E) with low heat resistance is used, a cured product can be formed that exhibits the inherent properties of the colorant (E).

[0142] The photosensitive coloring composition can obtain a cured product having excellent solvent resistance even when the baking temperature is low, so the colorant (E) is less likely to be eluted. Therefore, it is also possible to increase the content of the colorant (E) in the photosensitive coloring composition. A photosensitive coloring composition having a high content of the colorant (E) can be used, for example, as a material for the color pattern of a color filter to form a color filter with excellent color reproducibility.

[0143] The copolymer (A) contained in the photosensitive resin composition or photosensitive coloring composition has a structural unit (a-3) having an acid group, and therefore the photosensitive resin composition or photosensitive coloring composition has good alkaline developability. Such a photosensitive resin composition or photosensitive coloring composition has excellent alkaline developability, so that, for example, by applying it to a substrate to form a coating film, exposing it through a photomask corresponding to a predetermined pattern shape, developing the unexposed parts 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.

[0144] The photosensitive resin composition and the photosensitive coloring composition can be suitably used as materials for color filters.

[0145] For these reasons, the photosensitive resin composition and the photosensitive coloring composition are extremely useful as materials for forming components of image display elements such as pixels of color filters, black matrices, protective films for color filters, photospacers, protrusions for liquid crystal alignment, microlenses, and insulating films for touch panels.

[0146] <Cured Resin Film> The cured resin film of one embodiment is a cured product of a photosensitive resin composition or a photosensitive coloring composition.

[0147] The cured resin film can be produced, for example, by a method in which a photosensitive resin composition or a photosensitive coloring composition is applied to a substrate, the solvent (D) is removed by volatilization to form a coating film, the coating film is exposed to light to photocure it, and then a baking treatment is performed.

[0148] When forming a cured resin film having a predetermined 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 removed by volatilization to form a coating film. Next, the coating film is exposed to light through a photomask having a predetermined pattern shape to photocure the exposed portions. Next, the unexposed portions of the coating film are developed with an alkaline aqueous solution. Thereafter, the developed coating film is subjected to a baking treatment to form a cured resin film having a predetermined pattern shape.

[0149] When producing a cured resin film, known methods can be used for applying the photosensitive resin composition or the photosensitive coloring composition, exposing the applied film, and developing the same.

[0150] The conditions for the baking treatment performed when producing a cured resin film can be appropriately determined depending on the composition of the photosensitive resin composition or photosensitive coloring composition, the film thickness of the coating film, the material of the substrate, and the like. The baking treatment can be performed, for example, at a temperature of 70°C to 250°C. When the baking treatment temperature is 70°C or higher, the blocked isocyanato group possessed by the structural unit (a-1) having a blocked isocyanato group contained in the copolymer (A) in the photosensitive resin composition or photosensitive coloring composition is sufficiently dissociated. This generates an isocyanato group, which undergoes a crosslinking reaction with the hydroxy group possessed by the structural unit (a-2) having a hydroxy group. When the structural unit (a-1) has an alkyloxycarbonyl group, crosslinking occurs by ester exchange between the alkyl group of the alkyloxycarbonyl group and the structural unit (a-2) having a hydroxy group. As a result, a good degree of curing is achieved, and a cured product with excellent solvent resistance is obtained. When the structural unit (a-1) has an alkyloxycarbonyl group, both a deblocking reaction and a transesterification reaction can occur, but by adjusting the baking temperature, one of the reactions can proceed preferentially. The baking temperature is preferably 75°C or higher, more preferably 80°C or higher. A baking temperature of 250°C or lower is preferable because it is a condition that can be tolerated by materials with low heat resistance and discoloration of the photosensitive resin composition or photosensitive coloring composition can be suppressed. The photosensitive resin composition and the photosensitive coloring composition have good low-temperature curing properties. For this reason, the baking temperature can be set to 160°C or lower depending on the heat resistance of the substrate on which the cured resin film is formed. For example, when a resin substrate is used as the substrate, it may be set to 150°C or lower, 120°C or lower, or 100°C or lower.

[0151] The baking treatment carried out when producing a cured resin film can be carried out for, for example, 10 minutes to 4 hours, preferably 20 minutes to 2 hours, and can be appropriately determined depending on 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.

[0152] The cured resin film is a cured product of a photosensitive resin composition or a photosensitive coloring composition, and therefore can be produced by a baking treatment at a low temperature and has excellent solvent resistance.

[0153] The cured resin film can be preferably used as a constituent member of a transparent film, a protective film, an insulating film, an overcoat, a photospacer, a black matrix, a black column spacer, or a color filter.

[0154] <Color Filter> The color filter of one embodiment has a color pattern that is a cured product of a photosensitive coloring composition. The color filter preferably has a color pattern that is a cured product of a photosensitive coloring composition in which the content of the copolymer (A) is 10 to 90 mass% and the content of the reactive diluent (B) is 10 to 90 mass% relative to the total of the copolymer (A) and the reactive diluent (B), the content of the photopolymerization initiator (C) is 0.1 to 30 mass parts and the content of the colorant (E) is 0.1 to 80 mass parts relative to 100 mass parts of the total of the copolymer (A) and the reactive diluent (B), and the content of the solvent (D) is 30 to 1,000 mass parts relative to 100 mass parts of the total of the components excluding the solvent (D).

[0155] The color filter may include, for example, a substrate, RGB pixels formed thereon, a black matrix formed at the boundaries of each pixel, and a protective film formed on the pixels and the black matrix.

[0156] In the color filter, the pixels and the black matrix are color patterns formed from the cured product of the photosensitive coloring composition. In the color filter, known materials can be used for the components other than the materials of the pixels and the black matrix.

[0157] The substrate used for the color filter is not particularly limited, and a glass substrate, a silicon substrate, a polycarbonate substrate, a polyester substrate, a polyamide substrate, a polyamideimide substrate, a polyimide substrate, an aluminum substrate, a printed wiring board, an array substrate, or the like can be used as appropriate depending on the application.

[0158] <Method for Manufacturing Color Filter> Next, an exemplary method for manufacturing a color filter will be described. First, a colored pattern is formed on a substrate. Specifically, a colored pattern that will become a black matrix formed at the boundaries of each pixel, and a colored pattern that will become each of the RGB pixels are sequentially formed on the substrate by the method described below.

[0159] The colored pattern can be formed by photolithography. Specifically, a photosensitive colored composition is applied to a substrate to form a coating film. The coating film is then exposed to light through a photomask having a predetermined pattern shape, causing the exposed portions to photocure. The unexposed portions of the coating film are then developed with an alkaline aqueous solution. The developed coating film is then subjected to a baking treatment, thereby forming a colored pattern having a predetermined pattern shape.

[0160] The method for applying the photosensitive coloring composition is not particularly limited, but known methods such as screen printing, roll coating, curtain coating, spray coating, and spin coating can be used.

[0161] After the photosensitive coloring composition is applied to the substrate, the solvent (D) contained in the coating film may be volatilized and removed by heating the substrate using a heating means such as a circulation oven, an infrared heater, or a hot plate, as necessary. The conditions for heating the substrate to remove the solvent (D) are not particularly limited and may be appropriately set depending on the material of the substrate, the composition of the photosensitive coloring composition, the thickness of the coating film, etc. The substrate can be heated, for example, at a temperature of 50°C to 120°C for 30 seconds to 30 minutes.

[0162] Next, the coating film thus formed is partially exposed to active energy rays such as ultraviolet rays or excimer laser light through a negative photomask, and the exposed portions are photocured. The amount of active energy rays irradiated onto the coating film may be appropriately selected depending on the composition of the photosensitive coloring composition, and may be, for example, 30 to 2000 mJ / cm. ２The light source used for exposure is not particularly limited, but may be 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.

[0163] The alkaline aqueous solution used for developing the coating film is not particularly limited, but examples thereof include aqueous solutions of inorganic alkaline compounds such as sodium carbonate, potassium carbonate, calcium carbonate, sodium hydroxide, and potassium hydroxide; aqueous solutions of amine compounds such as ethylamine, diethylamine, and dimethylethanolamine; aqueous solutions of quaternary ammonium salts such as tetramethylammonium sulfate, hydrochloride, or p-toluenesulfonate; aqueous solutions of aniline compounds and salts thereof such as 3-methyl-4-amino-N,N-diethylaniline, 3-methyl-4-amino-N-ethyl-N-β-hydroxyethylaniline, 3-methyl-4-amino-N-ethyl-N-β-methanesulfonamidoethylaniline, and 3-methyl-4-amino-N-ethyl-N-β-methoxyethylaniline, and their sulfates, hydrochlorides, or p-toluenesulfonates; and aqueous solutions of p-phenylenediamine compounds and salts thereof. Additives such as antifoaming agents and surfactants may be added to the alkaline aqueous solution as needed.

[0164] After the coating film is developed using the above-mentioned aqueous alkaline solution, it is preferable to wash the coating film with water and dry it.

[0165] The conditions for the baking treatment carried out when producing a color filter can be appropriately determined depending on the composition of the photosensitive coloring composition, the film thickness of the coating film, the material of the substrate, etc. The baking temperature can be, for example, 70°C to 210°C. When the baking temperature is 70°C or higher, good curability is obtained, and a cured product having excellent solvent resistance is obtained. The baking temperature is preferably 75°C or higher, and more preferably 80°C or higher. When the baking temperature is 210°C or lower, it is preferable because a material with low heat resistance, such as a substrate with low heat resistance, can be used as the material for the color filter.

[0166] When a colored pattern of a color filter is formed using a conventional photosensitive coloring composition, if the baking temperature is 200 ° C. or less, the solvent resistance of the colored pattern is insufficient. In contrast, the photosensitive coloring composition of one embodiment has good low-temperature curing properties, so the baking temperature can be lowered compared to when using a conventional photosensitive coloring composition while ensuring the solvent resistance of the colored pattern. Specifically, the baking temperature can be 160 ° C. or less depending on the heat resistance of the substrate on which the resin cured film is formed. For example, when a colored pattern is formed using a resin substrate as the substrate, it may be 150 ° C. or less, 120 ° C. or less, or 100 ° C. or less.

[0167] The baking treatment carried out when producing a color filter can be carried out for, for example, 10 minutes to 4 hours, preferably 20 minutes to 2 hours, and can be appropriately determined depending on the composition of the photosensitive coloring composition, the temperature of the baking treatment, the film thickness of the coating film, etc.

[0168] The photosensitive coloring composition has good photocurability and low-temperature curability. Therefore, when a colored pattern is formed using the photosensitive coloring composition of one embodiment, if the baking temperature is the same as when a colored pattern is formed using a conventional photosensitive coloring composition, the baking time can be shortened, and a color filter can be efficiently formed.

[0169] Using the above-described method for manufacturing a colored pattern, a colored pattern that will become each of the RGB pixels and a colored pattern that will become a black matrix formed at the boundaries of each pixel are formed, and then a protective film is formed on the colored pattern (each of the RGB pixels and the black matrix).

[0170] 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 known materials and known methods.

[0171] Through the above steps, a color filter is obtained.

[0172] The color filter has a color pattern that is 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 performing a baking treatment at a low temperature. Therefore, the energy required for the baking treatment can be reduced.

[0173] In addition, a colorant (E) having low heat resistance can be used as the colorant (E) contained in the photosensitive coloring composition used as a material for the color filter. This allows for a wider range of options for the colorant (E). Therefore, for example, it is possible to form a color filter containing a colorant (E) having low heat resistance and having a color pattern that exhibits the inherent properties of the colorant (E) having low heat resistance.

[0174] Furthermore, the colored pattern in the color filter can be formed on a substrate with low heat resistance, such as a resin substrate, without damaging the substrate. This increases the options for usable substrates. Specifically, for example, since a color filter can be formed on a substrate with low heat resistance, such as a resin substrate, the display can be made more flexible. In addition, the colored pattern in the color filter has excellent solvent resistance, so there is little color change.

[0175] Here, the case where a photosensitive coloring composition containing a photopolymerization initiator (C) is used and a colored pattern is produced using a method of photocuring the photosensitive coloring composition has been described as an example, but for example, instead of the photopolymerization initiator (C) contained in the photosensitive coloring composition, a photosensitive coloring composition containing a curing accelerator and a known epoxy resin is used, and after applying it on a substrate by an inkjet method, a colored pattern that is a cured product of the photosensitive coloring composition containing the copolymer (A) may also be formed using a method of heating.

[0176] <Image Display Element> An image display element according to an embodiment includes a color filter. In the image display element, known components other than the color filter may be used. Specific examples of the image display element include a liquid crystal display element, an organic EL display element, and a solid-state imaging element such as a CCD element or a CMOS element.

[0177] Components other than the color filter in the image display element can be manufactured by known methods. For example, when manufacturing a liquid crystal display element as the image display element, it can be manufactured using the method shown below. First, a color filter is formed on a substrate using the method described above. Then, electrodes, spacers, etc. are formed sequentially on the substrate having the color filter. Next, electrodes, etc. are formed on another substrate, and the substrate having the color filter is placed opposite and bonded to it. Then, a predetermined amount of liquid crystal is injected between the opposing substrates and sealed.

[0178] The image display device has a color filter with excellent solvent resistance, and therefore, there is little color change.

[0179] The present invention will be explained in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[0180] A synthesis example of the copolymer (A) is shown below.

[0181] Example 1 Into a flask equipped with a stirrer, a dropping funnel, a condenser, a thermometer, and a gas inlet tube, 113 g of propylene glycol monomethyl ether (Tokyo Chemical Industry Co., Ltd.) was placed as a solvent (D), and the mixture was stirred while purging with nitrogen gas and heated to 78°C.

[0182] Next, 54 g (18 mol%) of a reaction product of 2-isocyanatoethyl acrylate and diethyl malonate as monomer (ma-1), 18 g (14 mol%) of 2-hydroxyethyl methacrylate as monomer (ma-2), 43 g (50 mol%) of methacrylic acid as monomer (ma-3), 33 g (18 mol%) of 2-ethylhexyl acrylate as monomer (ma-4), and 54 g (a total of 100% of the monomer components) of solvent (D) were added. A raw material monomer solution was prepared by mixing 69 g (46 parts by mass, based on 100 parts by mass of the total of the monomer components) of propylene glycol monomethyl ether as a solvent (D), 69 g (46 parts by mass, based on 100 parts by mass of the total of the monomer components) of propylene glycol monomethyl ether acetate as a solvent (D), and 18 g (12.1 parts by mass, based on 100 parts by mass of the total of the monomer components) of 2,2′-azobis(2,4-dimethylvaleronitrile) (FUJIFILM Wako Pure Chemical Industries, Ltd.) as a polymerization initiator.

[0183] The entire amount of the raw material monomer solution thus prepared was added dropwise to the solvent (D) in a flask under a nitrogen gas atmosphere at normal pressure using a dropping funnel over 1 hour. After the dropwise addition was completed, the solution in the flask was stirred and subjected to a polymerization reaction at 78°C for 3 hours to obtain a liquid containing the copolymer precursor and the solvent (D).

[0184] To a liquid containing the copolymer precursor and solvent (D) in a flask under normal pressure and under a nitrogen gas atmosphere, 0.6 g (0.3 parts by mass per 100 parts by mass of the total of the monomer components of the copolymer precursor and compound (e)) of hydroquinone monomethyl ether (MEHQ) as a polymerization inhibitor, 5.8 g (3.0 parts by mass per 100 parts by mass of the total of the monomer components of the copolymer precursor and compound (e)) of 4-dimethylaminopyridine (DMAP) (Kanto Chemical Co., Inc.) as a catalyst, and 43 g (30 moles per 100 moles of the total of the monomer components of the copolymer precursor) of glycidyl methacrylate as compound (e) were added, and the mixture was maintained at 78°C for 300 minutes with stirring to obtain a reaction liquid containing copolymer (A) and solvent (D). The weight average molecular weight, molecular weight distribution, hydroxyl group equivalent, and acid value of copolymer (A) were measured using the methods described above and are listed in Table 1. The blocked isocyanate group equivalent and ethylenically unsaturated group equivalent of copolymer (A) were calculated and are listed in Table 1. Regarding the addition reaction rate of compound (e), the amount of carboxyl group reduction (number of moles) was calculated by taking the difference between the acid value of the reaction solution when compound (e) was added and the acid value of the reaction solution after completion of the reaction, and the ratio of this to the number of moles of compound (e) added was determined as the addition reaction rate, which is shown in Table 1. The ethylenically unsaturated group equivalent of copolymer (A) was calculated from the amounts of raw materials charged and the addition reaction rate of compound (e).

[0185] To the reaction liquid containing the copolymer (A) and the solvent (D) thus obtained, propylene glycol monomethyl ether acetate (Tokyo Chemical Industry Co., Ltd.) was added as the solvent (D) so that the components other than the solvent were 35% by mass, thereby obtaining a liquid containing the copolymer (A) of Example 1.

[0186] Examples 2 to 27, Comparative Examples 2 and 3 Liquids containing copolymers (A) of Examples 2 to 27 and liquids containing copolymers (cA) of Comparative Examples 2 and 3 were obtained in the same manner as in Example 1, except that the monomers, compound (e), solvent (D), polymerization initiator, polymerization inhibitor, and catalyst, and the amounts thereof, shown in Table 1 were used. The weight average molecular weights, molecular weight distributions, hydroxyl group equivalents, and acid values ​​of the copolymers (A) of Examples 2 to 27 and the copolymers (cA) of Comparative Examples 2 and 3 were measured by the methods described above and are shown in Table 1. The blocked isocyanate group equivalents, ethylenically unsaturated group equivalents, and addition reaction rates of the copolymers (A) of Examples 2 to 27 and the copolymers (cA) of Comparative Examples 2 and 3 were calculated and are shown in Table 1.

[0187] [Comparative Examples 1 and 4] Liquids containing copolymers (cA) of Comparative Examples 1 and 4 were obtained in the same manner as in Example 1 to obtain a liquid containing a copolymer precursor and solvent (D), except that the monomers, solvent (D), and polymerization initiators in the amounts listed in Table 1 were used. The concentration was adjusted by adding propylene glycol monomethyl ether acetate (Tokyo Chemical Industry Co., Ltd.) as solvent (D) so that the components other than the solvent were 35% by mass. The weight average molecular weight, molecular weight distribution, hydroxyl group equivalent, and acid value of the copolymers (cA) of Comparative Examples 1 and 4 were measured using the methods described above and are listed in Table 1. The blocked isocyanate group equivalent of the copolymers (cA) of Comparative Examples 1 and 4 was calculated and is listed in Table 1.

[0188]

[0189] The following compounds were used as compounds listed in Table 1. AOI-DEM: Karenz™ AOI (2-isocyanatoethyl acrylate, Resonaq Co., Ltd.) and diethyl malonate reaction product (malonic acid-2-[[[[2-[1-oxo-2-propenyl]oxy]ethyl]amino]carbonyl]-1,3 diethyl ester) MOI-DEM: Karenz™ MOI (2-isocyanatoethyl methacrylate, Resonaq Co., Ltd.) and diethyl malonate reaction product (malonic acid-2-[[[2-methyl-1-oxo-2-propenyl]oxy]ethyl]amino]carbonyl]-1,3 diethyl ester) AOI-DMM: reaction product of Karenz™ AOI (2-isocyanatoethyl acrylate, Resonaq Co., Ltd.) with dimethyl malonate (malonic acid-2-[[[[2-[1-oxo-2-propenyl]oxy]ethyl]amino]carbonyl]-1,3-dimethyl ester); AOI-BP: reaction product of Karenz™ AOI (2-isocyanatoethyl acrylate, Resonaq Co., Ltd.) with 3,5-dimethylpyrazole (2-[(3,5-dimethylpyrazolyl)carbonylamino]ethyl acrylate); AOI-AM: reaction product of Karenz™ AOI (2-isocyanatoethyl acrylate, Resonaq Co., Ltd.) with methyl 4-hydroxybenzoate (4-[[[[2-[(1-oxo-2-propen-1-yl)oxy]ethyl]amino]carbonyl]oxy]-methyl benzoate). HEMA: 2-hydroxyethyl methacrylate (Nippon Shokubai Co., Ltd.) 4HBA: 4-hydroxybutyl acrylate (Tokyo Chemical Industry Co., Ltd.) 2-HPMA: 2-hydroxypropyl methacrylate (Tokyo Chemical Industry Co., Ltd.) GLM: 2,3-Dihydroxypropyl methacrylate (NOF Corporation) MAA: Methacrylic acid (Kuraray Co., Ltd.) AA: Acrylic acid (Tokyo Chemical Industry Co., Ltd.) HOMS(N): 2-Methacryloyloxyethyl succinic acid (Kyoeisha Chemical Co., Ltd.) HOAMS(N): 2-Acryloyloxyethyl succinic acid (Kyoeisha Chemical Co., Ltd.) 2EHA: 2-Ethylhexyl acrylate (Toagosei Co., Ltd.) BZMA: Benzyl methacrylate (Tokyo Chemical Industry Co., Ltd.) MMA: Methyl methacrylate (Tokyo Chemical Industry Co., Ltd.) SM: Styrene (Tokyo Chemical Industry Co., Ltd.) TCDMA: Tricyclodecanyl methacrylate (Resonac Corporation) GMA: Glycidyl methacrylate (Tokyo Chemical Industry Co., Ltd.) 4HBAGE: 4-Hydroxybutyl acrylate glycidyl ether (Mitsubishi Chemical Corporation) TTA15: 3,4-epoxycyclohexylmethyl methacrylate (Sun Chemical Co., Ltd.) TTA16: 3,4-epoxycyclohexylmethyl acrylate (Sun Chemical Co., Ltd.) PGMEA: Propylene glycol methyl ether acetate (Kuraray Co., Ltd.) PGME: Propylene glycol monomethyl ether (Kuraray Co., Ltd.) MB: 3-methoxy-1-butanol (Tokyo Chemical Industry Co., Ltd.) V-65B: 2,2'-azobis(2,4-dimethylvaleronitrile) (Fujifilm Wako Pure Chemical Industries, Ltd.) MEHQ: Hydroquinone monomethyl ether (Seiko Chemical Co., Ltd.) DMAP: 4-dimethylaminopyridine (Kanto Chemical Co., Ltd.) DMPP: Tris(2,6-dimethoxyphenyl)phosphine (Hokuko Sangyo Co., Ltd.) TPTP: Tri-para-tolylphosphine (Hokuko Sangyo Co., Ltd.) TCHP: Tricyclohexylphosphine (Hokuko Sangyo Co., Ltd.) TPP-PB: tetraphenylphosphonium bromide (Hokuko Sangyo Co., Ltd.),

[0190] [Storage Stability] The storage stability of the copolymers (A) of Examples 1 to 27 and the copolymers (cA) of Comparative Examples 1 to 4 was evaluated according to the following method. 10 g of each of the liquids containing the copolymers (A) of Examples 1 to 27, in which the components other than the solvent were 35% by mass, and the liquids containing the copolymers (cA) of Comparative Examples 1 to 4, in which the components other than the solvent were 35% by mass, was weighed into a 20 mL glass container, and the viscosity was measured. The viscosity measurements were performed within 24 hours of synthesis, and the viscosity before storage was determined. The viscosity was measured using an E-type viscometer (RE-80, rotor 1°34' x R24, Toki Sangyo Co., Ltd.) at 25°C and 20 rpm. Subsequently, each sample was stored stationary in an incubator maintained at 12°C for 3 months. Thereafter, the viscosity was measured again in the same manner as above, and the viscosity after storage was determined. Using the viscosity before and after storage, the viscosity increase rate was calculated using the following formula, and the results were evaluated according to the criteria shown below. The results are shown in Table 1. Viscosity increase rate (%) = (([Viscosity after storage] - [Viscosity before storage]) / [Viscosity before storage]) x 100 (Evaluation criteria for viscosity increase rate) Excellent: Viscosity increase rate less than 10% Good: Viscosity increase rate 10-20% Poor: Viscosity increase rate more than 20%

[0191] [Reference Examples 1 to 27, Comparative Reference Examples 1 to 4] Copolymers (A) of Examples 1 to 27 shown in Table 2, or copolymers (cA) of Comparative Examples 1 to 4, reactive diluent (B) dipentaerythritol pentaacrylate (Toagosei Co., Ltd.), photopolymerization initiator (C) 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl -] -, -1- (O-acetyloxime) (Ciba Japan Co., Ltd.), solvent (D) propylene glycol monomethyl ether acetate and propylene glycol monomethyl ether mixture (338 parts by mass, and 257 parts by mass, respectively), and colorant (E) Valifast Blue 2620 (phthalocyanine dye, Orient Chemical Industry Co., Ltd.) were mixed in the proportions shown in Table 2, respectively, to prepare photosensitive coloring compositions of Reference Examples 1 to 27, and Comparative Reference Examples 1 to 4. The amount of the solvent is not included in the blending amount of the copolymer (A) or (cA) shown in Table 2. The blending amount of the solvent (D) shown in Table 2 is the sum of the amount of the solvent contained in the liquid containing the copolymer (A) or copolymer (cA) obtained in the examples or comparative examples and the amount of the solvent added when preparing the photosensitive coloring composition.

[0192]

[0193] [Evaluation of Solvent Resistance] Solvent resistance was evaluated based on the film remaining rate.

[0194] (Film Remaining Rate) The photosensitive coloring compositions of Reference Examples 1 to 27 and Comparative Reference Examples 1 to 4 were each applied by spin coating onto a square non-alkali glass substrate measuring 5 cm in length and 5 cm in width in plan view, so that the thickness after exposure was 2.5 μm, to form a coating film. Then, the solvent (D) in the coating film was volatilized and removed by heating at 100° C. for 3 minutes.

[0195] Next, the coating film was irradiated with ultraviolet light having a wavelength of 365 nm at an energy dose of 100 mJ / cm ２ The coating film was then cured by baking at 85°C for 30 minutes to form a cured film. The thickness of the cured film was measured with a step gauge. The thickness at this time was designated X.

[0196] The resulting cured film was then immersed in 20 g of propylene glycol monomethyl ether acetate (PGMEA) at 23° C. for 15 minutes. After immersion, the coated film was vacuum dried at 40° C. for 30 minutes, and the thickness of the coated film was measured with a step gauge. The thickness at this time was designated Y.

[0197] The ratio of the thickness Y of the cured film after immersion in PGMEA to the thickness X of the cured film before immersion in PGMEA was calculated as the film remaining rate using the following formula, and the solvent resistance of the cured film was evaluated. In other words, the closer the film remaining rate is to 100%, the better the solvent resistance of the cured film. A film remaining rate of 70% or more was set as the pass mark for evaluation. The film remaining rates of the cured film are shown in Table 2. Film remaining rate = (Y / X) x 100 (%)

[0198] As shown in Table 2, the cured films of the photosensitive coloring compositions of Reference Examples 1 to 27 had a residual film rate (%) of 70% or more after immersion in PGMEA, and the baking temperature was as low as 85 ° C. Even though the solvent resistance was good.

[0199] [Evaluation of Developability] The developability was evaluated based on the solubility and adhesion of the cured film.

[0200] (Solubility) By spin coating method, the photosensitive coloring compositions prepared in Reference Examples 1 to 27 and Comparative Reference Examples 1 to 4 were each coated on a 5 cm square alkali-free glass substrate so that the thickness after exposure was 1.5 μm (coating process). The glass substrate coated with the photosensitive coloring composition was heated at 100 ° C. for 3 minutes to volatilize the solvent, and the coating film was dried (pre-baking process).

[0201] Next, an ultra-high pressure mercury lamp was used to irradiate 100 mJ / cm ２The surface of the dried coating film was irradiated with light through a photomask (exposure step). The exposure step was performed by placing the photomask 100 μm away from the coating film. The photomask used had a line-and-space pattern with a width of 3 to 100 μm. Next, Semiclean DL-A10 developer (Yokohama Yushi Kogyo Co., Ltd.) (300-fold diluted) was sprayed onto the surface of the coating film for 60 seconds at a temperature of 23°C and a pressure of 0.1 MPa to remove the unexposed areas (development step). The dissolution state of the coating film when sprayed with the developer was observed, and the solubility was evaluated according to the following criteria. The results are shown in Table 2. 1: No residue was found in the unexposed areas, no powder was observed in the developer, and the pattern shape was good. 2: No residue was found in the unexposed areas, but powder was observed in the developer, and the pattern shape was relatively good. 3: Residue remained in the unexposed areas, and there were areas where the pattern shape was missing. 4: The film peeled off in the exposed areas, and no pattern remained.

[0202] (Adhesion) The glass substrate having the coating film after the development step was left standing in a dryer at 100°C for 30 minutes to thermally cure the coating film (post-bake step), thereby obtaining a colored pattern. The colored pattern thus obtained was observed using a microscope, and adhesion was evaluated based on the minimum line width that could be developed, i.e., the minimum development dimension (µm). The results are shown in Table 2.

[0203] [Storage Stability of Photosensitive Coloring Composition] The storage stability of the photosensitive coloring compositions of Reference Examples 1 to 27 and Comparative Reference Examples 1 to 4 was evaluated according to the following method. 10 g of each of the photosensitive coloring compositions of Reference Examples 1 to 27 and Comparative Reference Examples 1 to 4 was weighed into a 20 mL glass container, and the viscosity was measured and determined as the viscosity before storage. The viscosity was measured using an E-type viscometer (RE-80, rotor 1°34' x R24, Toki Sangyo Co., Ltd.) at 25°C and 20 rpm. Subsequently, each sample was stored in an incubator maintained at 12°C for 3 months. Thereafter, the viscosity was measured again in the same manner as above and determined as the viscosity after storage. Using the viscosity before and after storage, the viscosity increase rate was calculated using the following formula and evaluated according to the criteria shown below. The results are shown in Table 2. Viscosity increase rate (%) = (([Viscosity after storage] - [Viscosity before storage]) / [Viscosity before storage]) x 100 (Evaluation criteria for viscosity increase rate) Excellent: Viscosity increase rate less than 10% Good: Viscosity increase rate 10-20% Poor: Viscosity increase rate more than 20%

Claims

1. A copolymer in which an ethylenically unsaturated compound (e) having a functional group reactive with an acid group is added to a portion of the acid group of the structural unit (a-3) having an acid group of a copolymer precursor containing a structural unit (a-1) having a blocked isocyanato group, a structural unit (a-2) having a hydroxyl group, and a structural unit (a-3) having an acid group.

2. The copolymer according to claim 1, having an ethylenically unsaturated group equivalent of 200 to 4,000 g / mol.

3. The copolymer according to claim 1 or 2, having an acid value of 10 to 300 KOHmg / g.

4. The copolymer according to claim 1 or 2, having a blocked isocyanato group equivalent of 200 to 6,000 g / mol and a hydroxyl group equivalent of 100 to 4,000 g / mol.

5. The copolymer according to claim 1 or 2, having a weight average molecular weight (Mw) of 1,000 to 50,000 and a molecular weight distribution (Mw / Mn) of 1.3 to 5.

0.

6. The copolymer according to claim 1 or 2, wherein the blocked isocyanato group of the structural unit (a-1) having the blocked isocyanato group is a group represented by the following formula (1) or the following formula (2): (In formula (1), R １ and R ２ each independently represents an alkyl group having 1 to 10 carbon atoms, and * represents a linking site with a residue remaining after removing the blocked isocyanato group from the structural unit (a-1) having a blocked isocyanato group. (In formula (2), R ３ represents an alkyl group having 1 to 10 carbon atoms, and * represents a linking site with a residue remaining after removing the blocked isocyanato group from the structural unit (a-1) having a blocked isocyanato group.

7. The copolymer according to claim 1 or 2, wherein the blocking agent constituting the blocked isocyanato group of the structural unit (a-1) having the blocked isocyanato group is at least one selected from the group consisting of pyrazole compounds, oxime compounds, and phenol compounds.

8. The structural unit (a-2) having a hydroxy group is —CH ２ 3. The copolymer according to claim 1, wherein the structural unit has a group represented by -OH.

9. The structural unit (a-2) having a hydroxy group is -(CH ２ ) ｎ A structural unit having a group represented by —OH (n is an integer of 2 to 6) and —(O—C ｘ H ２ｘ ) ｍ The copolymer according to claim 1 or 2, which is at least one selected from the group consisting of structural units having a group represented by -OH (wherein x is an integer of 2 to 4, and m is an integer of 2 to 6).

10. The copolymer according to claim 1 or 2, wherein the ethylenically unsaturated compound (e) is an epoxy group-containing (meth)acrylate.

11. The copolymer according to claim 1 or 2, wherein, based on all structural units of the copolymer precursor, the content of structural units (a-1) having a blocked isocyanato group is 5 to 40 mol %, the content of structural units (a-2) having a hydroxy group is 1 to 35 mol %, the content of structural units (a-3) having an acid group is 5 to 70 mol %, the amount of the ethylenically unsaturated compound (e) added is 1 to 55 mol per 100 mol of the structural units of the copolymer precursor, and the amount of the ethylenically unsaturated compound (e) added is 1 to 85 mol per 100 mol of the structural units (a-3) having an acid group of the copolymer precursor.

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