JP7779265B2 - Method for producing carboxyl group-containing resin and method for controlling molecular weight of carboxyl group-containing resin - Google Patents

Description

The present invention relates to a method for producing a carboxyl group-containing resin, a method for producing an ink, a method for producing a photosensitive resin composition, a method for producing a cured product, a method for producing a black matrix, a method for producing an image display device, and a method for controlling the molecular weight of a carboxyl group-containing resin.
This application claims priority based on Japanese Patent Application No. 2020-182984, filed on October 30, 2020, the contents of which are incorporated herein by reference.

A color filter typically consists of a black matrix formed on the surface of a transparent substrate such as glass or plastic, followed by pixels of three or more different colors, such as red, green, and blue, formed sequentially in a grid, stripe, or mosaic pattern. The pattern size varies depending on the application of the color filter and the individual colors, but is usually around 5 to 700 μm.

Currently, photolithography using a photosensitive resin composition is a well-known method for manufacturing color filters. When manufacturing color filters using photolithography, a photosensitive resin composition containing an alkaline-developable carboxyl-containing resin is first applied to a transparent substrate and dried. The composition is then imagewise exposed and developed using an alkaline developer, and then cured at a high temperature of 200°C or higher to form a pattern. However, such photosensitive resin compositions vary in line width and film thickness depending on the molecular weight of the carboxyl-containing resin. Therefore, large differences in molecular weight between production lots of the carboxyl-containing resin can lead to problems such as reduced color filter yields.

Given this background, there is a demand for a method for controlling the molecular weight of carboxyl group-containing resins and producing them stably. For example, Patent Documents 1 and 2 describe methods for producing carboxyl group-containing resins using specific conditions.

Japanese Patent Application Publication No. 2000-336116 Japanese Patent Application Publication No. 2005-41958

When the inventors produced carboxyl group-containing resins using the manufacturing methods described in Patent Documents 1 and 2, they found that the molecular weight stability between production lots was insufficient.

The present invention therefore aims to provide a method for producing a carboxyl group-containing resin that allows molecular weight control and has excellent performance stability between production lots, and a method for controlling the molecular weight of a carboxyl group-containing resin.

As a result of extensive research into resolving the above-mentioned problems, the inventors have discovered that the above-mentioned problems can be resolved by producing a carboxyl group-containing resin using a specific method. The gist of the present invention is as follows:

[1] A step A of reacting an epoxy compound (a) with an unsaturated monobasic acid (b) in an organic solvent to obtain a first reaction product A-containing liquid;
A step B of controlling the water content of the first reaction product A-containing liquid to obtain a second reaction product A-containing liquid;
and step C of adding a polybasic acid dianhydride (c) and a polybasic acid monoanhydride (d) to the second reaction product A-containing liquid and reacting them to obtain a carboxy group-containing resin.
[2] The method for producing a carboxyl group-containing resin according to [1], wherein water is added to the first reaction product A-containing liquid to control the water content of the first reaction product A-containing liquid, thereby obtaining the second reaction product A-containing liquid.
[3] The method for producing a carboxyl group-containing resin according to [2], wherein water is added to the first reaction product A-containing liquid so that the moisture content of the second reaction product A-containing liquid is 0.1 mass % or more and 0.5 mass % or less.
[4] The method for producing a carboxyl group-containing resin according to any one of [1] to [3], wherein in step C, a polyhydric alcohol (e) is further added and reacted.
[5] The method for producing a carboxyl group-containing resin according to [4], wherein the polyhydric alcohol (e) includes trimethylolpropane.
[6] The method for producing a carboxyl group-containing resin according to any one of [1] to [5], wherein the polybasic acid dianhydride (c) includes biphenyltetracarboxylic dianhydride.
[7] The method for producing a carboxyl group-containing resin according to any one of [1] to [6], wherein the polybasic acid monoanhydride (d) includes tetrahydrophthalic anhydride.
[8] A method for producing an ink containing (A) an alkali-soluble resin, an organic solvent, and (D) a colorant, comprising:
A method for producing an ink, comprising blending a carboxy group-containing resin produced by the production method according to any one of [1] to [7] as the alkali-soluble resin (A).
[9] A method for producing a photosensitive resin composition comprising (A) an alkali-soluble resin, (B) a photopolymerizable monomer, and (C) a photopolymerization initiator, comprising:
A method for producing a photosensitive resin composition, comprising blending, as the alkali-soluble resin (A), a carboxy group-containing resin produced by the production method according to any one of [1] to [7].
[10] The method for producing a photosensitive resin composition according to [9], wherein the photosensitive resin composition further contains (D) a colorant.
[11] A method for producing a cured product, comprising curing a photosensitive resin composition obtained by the method according to [9] or [10].
[12] A method for producing a black matrix, comprising forming a black matrix using a cured product obtained by the method for producing a black matrix according to [11].
[13] A method for producing an image display device, characterized by using a cured product obtained by the production method according to [11] or a black matrix obtained by the production method according to [12].
[14] A method for controlling the molecular weight of a carboxy group-containing resin, comprising: controlling the water content of a first reaction product A-containing liquid obtained by reacting an epoxy compound (a) with an unsaturated monobasic acid (b) in an organic solvent to obtain a second reaction product A-containing liquid; and adding a polybasic acid dianhydride (c) and a polybasic acid monoanhydride (d) to the second reaction product A-containing liquid and reacting them to obtain a carboxy group-containing resin.
[15] The method for controlling the molecular weight of a carboxy group-containing resin according to [14], wherein water is added to the first reaction product A-containing liquid to control the moisture content of the first reaction product A-containing liquid so that the moisture content of the solution containing the second reaction product A-containing liquid is 0.1 mass % or more and 0.5 mass % or less, thereby obtaining the second reaction product A-containing liquid.
[16] The method for controlling the molecular weight of a carboxyl group-containing resin according to [14] or [15], wherein the carboxyl group-containing resin is obtained by adding a polybasic acid dianhydride (c), a polybasic acid monoanhydride (d), and a polyhydric alcohol (e) to the second reaction product A-containing liquid and allowing them to react.
[17] The method for controlling the molecular weight of a carboxyl group-containing resin according to [16], wherein the polyhydric alcohol (e) includes trimethylolpropane.
[18] The method for controlling the molecular weight of a carboxy group-containing resin according to any one of [14] to [17], wherein the polybasic acid dianhydride (c) includes biphenyltetracarboxylic dianhydride.
[19] The method for controlling the molecular weight of a carboxy group-containing resin according to any one of [14] to [18], wherein the polybasic acid monoanhydride (d) includes tetrahydrophthalic anhydride.

The present invention provides a method for producing a carboxyl group-containing resin that allows molecular weight control and has excellent performance stability between production lots, as well as a method for controlling the molecular weight of a carboxyl group-containing resin.

1 is a schematic cross-sectional view showing an example of an organic EL element provided with a color filter according to the present invention.

The following describes in detail the embodiments of the present invention, but the present invention is not limited to the following embodiments and can be implemented with various modifications within the scope of the gist thereof.
In the present invention, "(meth)acrylic" means "acrylic and/or methacrylic", and the same applies to "(meth)acrylate" and "(meth)acryloyl".

In the present invention, the term "total solid content" refers to all components other than organic solvents and water contained in the photosensitive resin composition or the ink described below.
In the present invention, the "photosensitive resin composition" may be referred to as a "resist."
In the present invention, the weight average molecular weight refers to the weight average molecular weight (Mw) calculated in terms of polystyrene by gel permeation chromatography (GPC).
In the present invention, unless otherwise specified, the "amine value" refers to the amine value calculated as the effective solid content, and is a value expressed as the mass of KOH equivalent to the amount of base per 1 g of the solid content of the dispersant. The measurement method will be described later.

[Method of producing carboxyl group-containing resin]
The method for producing a carboxyl group-containing resin of the present invention includes step A of reacting an epoxy compound (a) with an unsaturated monobasic acid (b) in an organic solvent to obtain a first reaction product A-containing liquid, step B of controlling the water content of the first reaction product A-containing liquid obtained in step A to obtain a second reaction product A-containing liquid, and step C of adding a polybasic acid dianhydride (c) and a polybasic acid monoanhydride (d) to the second reaction product A-containing liquid obtained in step B and reacting them to obtain a carboxyl group-containing resin.
The reaction product A contained in the first reaction product A-containing liquid obtained in step A can be considered an intermediate of the carboxyl group-containing resin, and may be referred to as an "intermediate" hereinafter. The reaction product A contained in the second reaction product A-containing liquid obtained in step B may also be referred to as an "intermediate" in the same manner.
The reaction product A-containing liquid containing the first reaction product A-containing liquid and the second reaction product A-containing liquid may be a suspension, dispersion, or solution as long as it is a liquid mixture containing reaction product A, and is preferably a reaction product A-containing solution.

<Process A>
Step A is a step of synthesizing a reaction product A (intermediate) by reacting an epoxy compound (a) with an unsaturated monobasic acid (b) in an organic solvent, and obtaining a first reaction product A-containing liquid containing the reaction product A.

The epoxy compound (a) is not particularly limited as long as it is a compound having an epoxy group. Examples thereof include bisphenol A type epoxy resins (e.g., "jER (registered trademark, the same applies hereinafter) 828,""jER1001,""jER1002," and "jER1004," manufactured by Mitsubishi Chemical Corporation), epoxy resins obtained by reacting an alcoholic hydroxyl group of a bisphenol A type epoxy resin with epichlorohydrin (e.g., "NER-1302" manufactured by Nippon Kayaku Co., Ltd. (epoxy equivalent: 323, softening point: 76°C)), and bisphenol F type resins (e.g., "jER807,""EP-4001," and "EP- 4002, "EP-4004, etc."), epoxy resins obtained by reacting an alcoholic hydroxyl group of a bisphenol F type epoxy resin with epichlorohydrin (for example, "NER-7406" manufactured by Nippon Kayaku Co., Ltd. (epoxy equivalent: 350, softening point: 66°C)), bisphenol S type epoxy resin, biphenyl glycidyl ether (for example, "YX-4000" manufactured by Mitsubishi Chemical Corporation), phenol novolac type epoxy resin (for example, "EPPN-201" manufactured by Nippon Kayaku Co., Ltd., "EP-152" manufactured by Mitsubishi Chemical Corporation, EP-154, "DEN-438" manufactured by The Dow Chemical Company), (o, m, p-)cresol novolac type epoxy resins (for example, "EOCN (registered trademark, the same applies hereinafter)-102S,""EOCN-1020," and "EOCN-104S" manufactured by Nippon Kayaku Co., Ltd.), triglycidyl isocyanurate (for example, "TEPIC (registered trademark)" manufactured by Nissan Chemical Industries, Ltd.), trisphenolmethane type epoxy resins (for example, "EPPN (registered trademark, the same applies hereinafter)-501,""EPPN-502," and "EPPN Suitable examples of epoxy resins that can be used include alicyclic epoxy resins (Daicel Corporation's "CELLOXIDE (registered trademark; the same applies hereinafter) 2021P" and "CELLOXIDE EHPE"), epoxy resins obtained by glycidylating phenolic resins obtained by reacting dicyclopentadiene with phenol (for example, DIC Corporation's "EXA-7200" and Nippon Kayaku Co., Ltd.'s "NC-7300"), copolymers of epoxy group-containing (meth)acrylates and other radically polymerizable monomers, and epoxy compounds represented by the following general formulas (a1) to (a6).
Specific examples of the epoxy compound represented by the following general formula (a1) include "XD-1000" manufactured by Nippon Kayaku Co., Ltd.; the epoxy compound represented by the following general formula (a2) includes "NC-3000" manufactured by Nippon Kayaku Co., Ltd.; and the epoxy compound represented by the following general formula (a4) includes "ESF-300" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.

In the above general formula (a1), b11 represents an average value and is a number from 0 to 10. ^R11 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, or a biphenyl group. Note that multiple ^R11s present in one molecule may be the same or different.

In the above general formula (a2), b12 represents an average value and is a number from 0 to 10. ^R21 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, or a biphenyl group. Note that multiple ^R21 present in one molecule may be the same or different.

In the above general formula (a3), X represents a linking group represented by the following general formula (a3-1) or (a3-2), provided that the molecular structure contains one or more adamantane structures. b13 represents an integer of 2 or 3.

Of these, from the viewpoint of the patterning characteristics of the resist, X is preferably (a3-1) and b13 is preferably 2.

In the above general formulae (a3-1) and (a3-2), R ³¹ to R ³⁴ and R ³⁵ to R ³⁷ each independently represent an adamantyl group which may have a substituent, a hydrogen atom, an alkyl group having 1 to 12 carbon atoms which may have a substituent, or a phenyl group which may have a substituent. In addition, * in the formulas represents a bonding site in formula (a3).

From the viewpoint of resist patterning properties, formula (a3-1) preferably has two adamantyl groups and two hydrogen atoms. From the viewpoint of resist patterning properties, formula (3a-2) preferably has two adamantyl groups and one hydrogen atom.

In the general formula (a4), p and q each independently represent an integer of 0 to 4, ^R41 and ^R42 each independently represent an alkyl group having 1 to 20 carbon atoms or a halogen atom, ^R43 and ^R44 each independently represent an alkylene group having 1 to 5 carbon atoms, and x and y each independently represent an integer of 0 or greater.

Of these, from the viewpoint of the patterning characteristics of the resist, it is preferable that p, q, x, and y are 0.

In the above general formula (a5), R ⁵¹ to R ⁵⁴ each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, R ⁵⁵ each independently represent an alkylene group having 1 to 5 carbon atoms, aryl group having 6 to 20 carbon atoms, or aralkyl group having 7 to 20 carbon atoms, and R ⁵⁶ each independently represent an alkylene group having 1 to 5 carbon atoms. k is an integer of 1 to 5, l is an integer of 0 to 13, and m is each independently an integer of 0 to 5.

Among these, from the viewpoint of the patterning properties of the resist, R ⁵¹ to R ⁵⁴ are preferably hydrogen atoms, k is preferably 2, and l and m are preferably 0.

In the above general formula (a6), n and o each independently represent an integer of 1 to 9.
^R23 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, or a biphenyl group. Note that multiple ^R23s present in one molecule may be the same or different.

Of these, from the viewpoint of resist patterning properties, it is preferable to use an epoxy compound represented by any of general formulas (a1) to (a6), more preferably an epoxy compound represented by (a3), (a4), or (a5), and even more preferably an epoxy compound represented by (a5).

The unsaturated monobasic acid (b) may be any compound having only one acid group and one or more radically polymerizable unsaturated bonds in one molecule, and the acid group is preferably a carboxy group.
By reacting the epoxy compound (a) with the unsaturated monobasic acid (b) in an organic solvent, the acid group reacts with the epoxy group of the epoxy compound, thereby obtaining a first reaction product A-containing liquid containing an intermediate in which a radically polymerizable double bond has been introduced into the epoxy compound.

Examples of unsaturated monobasic acids (b) include monocarboxylic acids such as (meth)acrylic acid, crotonic acid, o-, m-, and p-vinylbenzoic acid, α-substituted (meth)acrylic acid with haloalkyl, alkoxyl, halogen, nitro, and cyano groups, 2-(meth)acryloyloxyethyl succinic acid, 2-(meth)acryloyloxyethyl adipate, 2-(meth)acryloyloxyethyl phthalic acid, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, 2-(meth)acryloyloxyethyl maleic acid, 2-(meth)acryloyloxypropyl succinic acid, 2-(meth)acryloyloxypropyl adipate, 2-(meth)acryloyloxypropyl tetrahydrophthalic acid, 2-(meth)acryloyloxypropyl phthalic acid, 2-(meth)acryloyloxypropyl maleic acid, and 2-(meth)acryloyloxybutyl succinic acid. , 2-(meth)acryloyloxybutyl adipic acid, 2-(meth)acryloyloxybutyl hydrophthalic acid, 2-(meth)acryloyloxybutyl phthalic acid, 2-(meth)acryloyloxybutyl maleic acid, a monomer having one terminal carboxy group obtained by adding a lactone such as ε-caprolactone, β-propiolactone, γ-butyrolactone or δ-valerolactone to (meth)acrylic acid, a monomer having one terminal hydroxyl group such as hydroxyalkyl (meth)acrylate, a (meth)acrylic acid ester having one or more ethylenically unsaturated groups and one terminal carboxy group obtained by adding an acid (anhydride) such as (succinic anhydride), (phthalic anhydride) or (maleic anhydride) to a compound having one terminal hydroxyl group such as pentaerythritol tri(meth)acrylate, and a (meth)acrylic acid dimer.

From the viewpoint of resist sensitivity and stability over time, the unsaturated monobasic acid (b) is preferably an alkenyl carboxylic acid, and more preferably (meth)acrylic acid.

Examples of organic solvents that can be used include propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, methyl 3-methoxypropionate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-butyl ether acetate, diethylene glycol monoethyl ether acetate, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, toluene, and xylene. Among these, from the standpoint of reaction yield, propylene glycol monomethyl ether acetate and 3-methoxybutyl acetate are preferred, with propylene glycol monomethyl ether acetate being more preferred.

Known methods can be used to react the epoxy compound (a) with the unsaturated monobasic acid (b) in an organic solvent to obtain an intermediate. For example, the epoxy compound (a) can be reacted with the unsaturated monobasic acid (b) in an organic solvent in the presence of a catalyst and a polymerization inhibitor at a temperature of 50 to 150°C.

Examples of catalysts that can be used include tertiary phosphines such as triethylphosphine, tributylphosphine, tricyclohexylphosphine, and triphenylphosphine; tertiary amines such as triethylamine, trimethylamine, benzyldimethylamine, and benzyldiethylamine; and quaternary ammonium salts such as tetramethylammonium chloride, tetraethylammonium chloride, and dodecyltrimethylammonium chloride. Among these, tertiary phosphines are preferred from the standpoint of reaction yield, and triphenylphosphine is more preferred.

Examples of polymerization inhibitors that can be used include hydroquinone, methylhydroquinone, trimethylhydroquinone, paramethoxyphenol, and 2,6-di-tert-butyl-4-cresol. Among these, paramethoxyphenol and 2,6-di-tert-butyl-4-cresol are preferred, with paramethoxyphenol being more preferred, from the standpoints of reaction yield and resist sensitivity.

The epoxy compound (a), unsaturated monobasic acid (b), organic solvent, catalyst, and polymerization inhibitor may each be used alone or in combination of two or more.

The amount of unsaturated monobasic acid (b) used is preferably in the range of 0.5 to 1.5 equivalents per equivalent of epoxy group in epoxy compound (a), and more preferably in the range of 0.8 to 1.2 equivalents. By using an amount of unsaturated monobasic acid (b) that is equal to or greater than the lower limit mentioned above, the amount of residual epoxy is reduced, which tends to suppress gelation during the reaction with the polybasic acid anhydride in step B. Furthermore, by using an amount that is equal to or less than the upper limit mentioned above, it tends to suppress the unsaturated monobasic acid (b) from remaining as an unreacted product.

<Process B>
Step B is a step of controlling the water content of the first reaction product A-containing liquid obtained in step A to obtain a second reaction product A-containing liquid.
By including step B in the method for producing a carboxyl group-containing resin of the present invention, it becomes possible to control the molecular weight of the carboxyl group-containing resin.

The method for controlling the moisture content of the first reaction product A-containing liquid obtained in step A is not particularly limited, but examples include a method of adding water to the first reaction product A-containing liquid and a method of dehydrating the first reaction product A-containing liquid.

When water is added to the first reaction product A-containing liquid, water may be added alone or as a mixture of water and an organic solvent. The temperature of the first reaction product A-containing liquid at the time of addition is preferably 20°C to 80°C, more preferably 30°C to 70°C, even more preferably 40°C to 60°C, and particularly preferably 45°C to 55°C. By setting the temperature within this range, water can be uniformly dispersed and dissolved in the first reaction product A-containing liquid.
The addition of water to the first reaction product A-containing liquid is preferably carried out while stirring the first reaction product A-containing liquid, which allows the water to be uniformly dispersed and dissolved in the first reaction product A-containing liquid.

The amount of water added to the first reaction product A-containing liquid is preferably added so that the water content of the second reaction product A-containing liquid obtained in step B is 0.01% by mass or more, more preferably 0.03% by mass or more, even more preferably 0.06% by mass or more, particularly preferably 0.1% by mass or more, and particularly preferably 0.18% by mass or more. Also, 1% by mass or less is preferred, more preferably 0.8% by mass or less, even more preferably 0.6% by mass or less, particularly preferably 0.5% by mass or less, and particularly preferably 0.4% by mass or less. By setting the amount to be above the lower limit, the amount of resist residue tends to be reduced. Furthermore, by setting the amount to be below the upper limit, the stability of the resist over time tends to be improved.
The upper and lower limits can be combined in any manner. For example, the content is preferably 0.01 to 1 mass%, more preferably 0.03 to 0.8 mass%, even more preferably 0.06 to 0.6 mass%, particularly preferably 0.1 to 0.5 mass%, and particularly preferably 0.18 to 0.4 mass%.

Examples of a method for dehydrating the first reaction product A-containing liquid include a method of drying using a porous material such as a molecular sieve or silica gel, or a dehydrating agent such as calcium chloride, and a method of distilling off the water under reduced pressure using a vacuum device. Among these, the method of distilling off the water under reduced pressure is preferred from the viewpoint of the purity and yield of the carboxy group-containing resin.
When the distillation is carried out under reduced pressure, the pressure in the reaction vessel containing the first reaction product A-containing liquid is preferably 70 kPa or less, more preferably 60 kPa or less, even more preferably 50 kPa or less, and particularly preferably 40 kPa or less.

In step B, from the standpoint of reaction time, it is preferable to include a step of adding water to the first reaction product A-containing liquid obtained in step A to control the water content of the first reaction product A-containing liquid and obtain a second reaction product A-containing liquid.

The moisture content of the reaction product A-containing liquid can be calculated using the Karl Fischer measurement method described in JIS K0113 (2005). Various moisture meters can be used, including the MKA-610 manufactured by Kyoto Electronics Manufacturing Co., Ltd.

<Process C>
Step C is a step of adding polybasic acid dianhydride (c) and polybasic acid monoanhydride (d) to the second reaction product A-containing liquid obtained in step B and reacting them to obtain a carboxy group-containing resin.

The polybasic acid dianhydride (c) may be any compound having only two acid anhydride groups per molecule. From the perspective of resist patterning properties, it preferably contains a compound represented by general formula (c1):

In the above formula (c1), A is a tetravalent organic group derived from a polybasic acid dianhydride.

Examples of the polybasic acid dianhydride (c) represented by general formula (c1) include biphenyltetracarboxylic dianhydride (BPDA), bicyclohexyltetracarboxylic dianhydride, pyromellitic anhydride, and benzophenonetetracarboxylic dianhydride. Among these, biphenyltetracarboxylic dianhydride (BPDA) and pyromellitic anhydride are preferred, with biphenyltetracarboxylic dianhydride (BPDA) being more preferred, from the perspective of resist patterning characteristics.

The polybasic acid monoanhydride (d) may be any compound having only one acid anhydride group per molecule. Examples include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, nadic anhydride, and trimellitic anhydride. Among these, succinic anhydride, phthalic anhydride, and tetrahydrophthalic anhydride are preferred, with tetrahydrophthalic anhydride being more preferred, from the standpoint of resist patterning properties.

The polybasic acid dianhydride (c) and the polybasic acid monoanhydride (d) may be used alone or in combination of two or more.

A known method can also be used for the reaction of synthesizing a carboxyl group-containing resin by adding polybasic acid dianhydride (c) and polybasic acid monoanhydride (d) to the second reaction product A-containing liquid and reacting them. For example, polybasic acid dianhydride (c) and polybasic acid monoanhydride (d) can be added to the second reaction product A-containing liquid and reacted at a temperature of 50 to 150°C.

When the polybasic acid dianhydride (c) and the polybasic acid monoanhydride (d) are added to the second reaction product A-containing solution and reacted, a polyhydric alcohol (e) may also be added and reacted.
By further adding the polyhydric alcohol (e) and reacting it, a multi-branched structure can be introduced into the resulting carboxyl group-containing resin, improving the patterning properties of the resist.

Examples of polyhydric alcohols that can be used as the polyhydric alcohol (e) include trimethylolpropane, pentaerythritol, and dipentaerythritol. Among these, trimethylolpropane is preferred from the viewpoint of resist patterning properties.

The amount of polyhydric alcohol (e) used is preferably 0.01 equivalents or more, more preferably 0.03 equivalents or more, and even more preferably 0.05 equivalents or more, relative to 1 equivalent of unsaturated monobasic acid (b). Also, it is preferably 1 equivalent or less, more preferably 0.9 equivalents or less, and even more preferably 0.8 equivalents or less. By setting it to the lower limit or more, the stability of the resist over time tends to improve, and by setting it to the upper limit or less, the resist sensitivity tends to improve.
The upper and lower limits can be arbitrarily combined. For example, 0.01 to 1 equivalent is preferable, 0.03 to 0.9 equivalent is more preferable, and 0.05 to 0.8 equivalent is even more preferable.

The amount of polybasic acid dianhydride (c) used is preferably 0.1 equivalents or more, more preferably 0.3 equivalents or more, and even more preferably 0.5 equivalents or more, relative to 1 equivalent of polybasic acid monoanhydride (d). Also, it is preferably 50 equivalents or less, more preferably 30 equivalents or less, and even more preferably 10 equivalents or less. By setting it to the lower limit or more, the adhesion of the resist tends to be improved, and by setting it to the upper limit or less, the amount of resist residue tends to be reduced.
The upper and lower limits can be arbitrarily combined. For example, 0.1 to 50 equivalents is preferable, 0.3 to 30 equivalents is more preferable, and 0.5 to 10 equivalents is even more preferable.

The acid value of the carboxyl group-containing resin produced by the method of the present invention is preferably 10 mgKOH/g or more, more preferably 30 mgKOH/g or more, even more preferably 50 mgKOH/g or more, and particularly preferably 80 mgKOH/g or more. Also, it is preferably 250 mgKOH/g or less, more preferably 200 mgKOH/g or less, even more preferably 150 mgKOH/g or less, and particularly preferably 130 mgKOH/g or less. By setting it to the lower limit or more, the amount of resist residue tends to be reduced. Also, by setting it to the upper limit or less, the adhesion of the resist tends to be improved.
The upper and lower limits can be combined in any manner. For example, 10 to 250 mgKOH/g is preferred, 30 to 200 mgKOH/g is more preferred, 50 to 150 mgKOH/g is even more preferred, and 80 to 130 mgKOH/g is particularly preferred.

The weight average molecular weight of the carboxyl group-containing resin produced by the production method of the present invention is preferably 3,000 or more, more preferably 5,000 or more, even more preferably 8,000 or more, and particularly preferably 12,000 or more. Also, it is preferably 22,000 or less, more preferably 21,000 or less. By setting it to the lower limit or more, the adhesion of the resist tends to be improved. Also, by setting it to the upper limit or less, the amount of resist residue tends to be reduced.
The upper and lower limits can be combined in any manner. For example, 3,000 to 22,000 is preferable, 5,000 to 22,000 is more preferable, 8,000 to 21,000 is even more preferable, and 12,000 to 21,000 is particularly preferable.

[Carboxy group-containing resin-containing liquid]
The carboxyl group-containing resin-containing liquid obtained in step C contains a carboxyl group-containing resin, an organic solvent, and water. The moisture content of the resulting carboxyl group-containing resin-containing liquid is preferably 0.01% by mass or more and 1% by mass or less.
By ensuring that the moisture content is within the above range, the residue of the resist using the carboxyl group-containing resin-containing liquid tends to be reduced, and the stability of the resist over time tends to be improved.
The water content of the carboxyl group-containing resin-containing liquid is preferably 0.01% by mass or more and 1% by mass or less, more preferably 0.03% by mass or more, even more preferably 0.06% by mass or more, particularly preferably 0.1% by mass or more, and particularly preferably 0.18% by mass or more. Also, 0.8% by mass or less is more preferred, 0.6% by mass or less is even more preferred, 0.5% by mass or less is particularly preferred, and 0.4% by mass or less is particularly preferred. The above upper and lower limits can be arbitrarily combined. For example, 0.03% by mass or more and 0.8% by mass or less is preferred, 0.06% by mass or more and 0.6% by mass or less is more preferred, 0.1% by mass or more and 0.5% by mass or less is even more preferred, and 0.18% by mass or more and 0.4% by mass or less is particularly preferred. Setting the water content at or above the lower limit tends to reduce the residue of the resist using the resin solution. Setting the water content at or below the upper limit tends to improve the stability of the resist over time.

The carboxyl group-containing resin of the present invention contained in the carboxyl group-containing resin-containing liquid is preferably a carboxyl group-containing resin produced by the production method of the present invention.
The carboxyl group-containing resin of the present invention preferably has a structure derived from the epoxy compound (a).
The carboxyl group-containing resin of the present invention preferably has a structure derived from the unsaturated monobasic acid (b).
The carboxyl group-containing resin of the present invention preferably has a structure derived from the polybasic acid dianhydride (c).
The carboxyl group-containing resin of the present invention preferably has a structure derived from the polybasic acid monoanhydride (d).
The carboxyl group-containing resin of the present invention preferably has a structure derived from the polyhydric alcohol (e).
The preferred types and preferred blending amounts of the epoxy compound (a), the unsaturated monobasic acid (b), the polybasic acid dianhydride (c), the polybasic acid monoanhydride (d), and the polyhydric alcohol (e) are the same as the types and blending amounts described above.

The organic solvent contained in the carboxyl group-containing resin-containing liquid can preferably be the organic solvent used in the method for producing the carboxyl group-containing resin of the present invention.

[Photosensitive resin composition]
The method for producing a photosensitive resin composition of the present invention is a method for producing a photosensitive resin composition containing (A) an alkali-soluble resin, (B) a photopolymerizable monomer, and (C) a photopolymerization initiator, and includes blending the carboxyl group-containing resin produced by the production method of the present invention as the alkali-soluble resin (A). The photosensitive resin composition produced by the production method of the present invention may also contain (D) a colorant.

<(A) Alkali-soluble resin>
The photosensitive resin composition of the present invention contains, as the alkali-soluble resin (A), the carboxyl group-containing resin obtained by the production method of the present invention, and thus the performance stability between production lots is improved.
The alkali-soluble resin (A) may contain other alkali-soluble resins.

Other alkali-soluble resins are not particularly limited as long as the solubility of the exposed and unexposed areas in alkali development changes after exposure of the coating film obtained by applying and drying the photosensitive resin composition. However, alkali-soluble resins having a carboxy group are preferred. Furthermore, those having an ethylenically unsaturated group are preferred, and alkali-soluble resins having an ethylenically unsaturated group and a carboxy group are even more preferred. Specific examples include epoxy (meth)acrylate resins and acrylic copolymer resins having a carboxy group, such as the alkali-soluble resins described below as (A1-1), (A2-1), (A2-2), (A2-3), and (A2-4). These may be used alone or in combination of two or more. Of the above, epoxy (meth)acrylate resins having a carboxy group (A1-1) are particularly preferred.

When creating color filters, polymer resins containing acidic functional groups such as hydroxyl, carboxyl, phosphate, and sulfonic acid groups are used because the unexposed areas dissolve in alkaline developers. Among these, polymer resins containing carboxyl groups are preferred from the perspective of solubility in alkaline developers. Furthermore, while phosphate and sulfonic acid groups are more acidic than carboxyl groups, they are more likely to react with initiators, monomers, dispersants, and other additives containing basic groups in photosensitive resin compositions, potentially resulting in poor storage stability.

Examples of epoxy (meth)acrylate resins having carboxy groups include the following epoxy (meth)acrylate resin (A1-1).

<Epoxy (meth)acrylate resin (A1-1)>
An alkali-soluble resin obtained by adding an unsaturated monobasic acid to an epoxy compound and then reacting it with a polybasic acid monoanhydride.

<Epoxy (meth)acrylate resin (A1-1) having a carboxy group and an ethylenically unsaturated group bond>
Examples of epoxy compounds that can be used as raw materials include bisphenol A epoxy resins (e.g., Mitsubishi Chemical Corporation's "jER (registered trademark; the same applies hereinafter) 828,""jER1001,""jER1002," and "jER1004"); epoxy resins obtained by reacting an alcoholic hydroxyl group of a bisphenol A epoxy resin with epichlorohydrin (e.g., Nippon Kayaku Co., Ltd.'s "NER-1302" (epoxy equivalent: 323, softening point: 76°C)); and bisphenol F resins (e.g., Mitsubishi Chemical Corporation's " Epoxy resins obtained by reacting an alcoholic hydroxyl group of a bisphenol F type epoxy resin with epichlorohydrin (for example, "NER-7406" manufactured by Nippon Kayaku Co., Ltd. (epoxy equivalent: 350, softening point: 66°C)), bisphenol S type epoxy resin, biphenyl glycidyl ether (for example, "YX-4000" manufactured by Mitsubishi Chemical Corporation), phenol novolac type epoxy resin (for example, "EP-4001" manufactured by Nippon Kayaku Co., Ltd. (EP-4002)), PN-201" manufactured by Mitsubishi Chemical Corporation, "EP-152" and "EP-154" manufactured by The Dow Chemical Company, "DEN-438" manufactured by The Dow Chemical Company), (o, m, p-)cresol novolac type epoxy resins (for example, "EOCN (registered trademark; the same applies hereinafter)-102S", "EOCN-1020", and "EOCN-104S" manufactured by Nippon Kayaku Co., Ltd.), triglycidyl isocyanurate (for example, "TEPIC (registered trademark)" manufactured by Nissan Chemical Industries, Ltd.), trisphenolmethane type epoxy resins (for example, "EPPN ( Suitable epoxy resins that can be used include epoxy resins represented by the following general formulas (a1) to (a6): cycloaliphatic epoxy resins (CELLOXIDE (registered trademark; the same applies hereinafter)-501, EPPN-502, and EPPN-503 manufactured by Daicel Corporation; CELLOXIDE 2021P and CELLOXIDE EHPE manufactured by Daicel Corporation; epoxy resins obtained by glycidylating phenolic resins obtained by reacting dicyclopentadiene with phenol (e.g., EXA-7200 manufactured by DIC Corporation and NC-7300 manufactured by Nippon Kayaku Co., Ltd.); and epoxy resins represented by the following general formulas (a1) to (a6).
Specific examples of epoxy resins represented by the following general formula (a1) include "XD-1000" manufactured by Nippon Kayaku Co., Ltd.; epoxy resins represented by the following general formula (a2) include "NC-3000" manufactured by Nippon Kayaku Co., Ltd.; and epoxy resins represented by the following general formula (a4) include "ESF-300" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.

In the above general formula (a1), b11 represents an average value and is a number from 0 to 10. ^R11 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, or a biphenyl group. Note that multiple ^R11s present in one molecule may be the same or different.

In the above general formula (a2), b12 represents an average value and is a number from 0 to 10. ^R21 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, or a biphenyl group. Note that multiple ^R21 present in one molecule may be the same or different.

In the above general formula (a3), X represents a linking group represented by the following general formula (a3-1) or (a3-2), provided that the molecular structure contains one or more adamantane structures. b13 represents an integer of 2 or 3.

In the above general formulae (a3-1) and (a3-2), R ³¹ to R ³⁴ and R ³⁵ to R ³⁷ each independently represent an adamantyl group which may have a substituent, a hydrogen atom, an alkyl group having 1 to 12 carbon atoms which may have a substituent, or a phenyl group which may have a substituent. In addition, * in the formulas represents a bonding site in formula (a3).
From the viewpoint of resist patterning properties, formula (a3-1) preferably has two adamantyl groups and two hydrogen atoms, and formula (a3-2) preferably has two adamantyl groups and one hydrogen atom.

In the general formula (a4), p and q each independently represent an integer of 0 to 4, ^R41 and ^R42 each independently represent an alkyl group having 1 to 20 carbon atoms or a halogen atom, ^R43 and ^R44 each independently represent an alkylene group having 1 to 5 carbon atoms, and x and y each independently represent an integer of 0 or greater.

In the above general formula (a5), R ⁵¹ to R ⁵⁴ each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, R ⁵⁵ each independently represent an alkylene group having 1 to 5 carbon atoms, aryl group having 6 to 20 carbon atoms, or aralkyl group having 7 to 20 carbon atoms, and R ⁵⁶ each independently represent an alkylene group having 1 to 5 carbon atoms. k is an integer of 1 to 5, l is an integer of 0 to 13, and m is each independently an integer of 0 to 5.

In the above general formula (a6), n and o each independently represent an integer of 1 to 9.
^R23 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a phenyl group, a naphthyl group, or a biphenyl group. Note that multiple ^R23s present in one molecule may be the same or different.

Among these, it is preferable to use epoxy compounds represented by any of general formulas (a1), (a2) or (a6).

Examples of unsaturated monobasic acids include (meth)acrylic acid, crotonic acid, o-, m-, and p-vinylbenzoic acid, monocarboxylic acids such as (meth)acrylic acid substituted with haloalkyl, alkoxyl, halogen, nitro, and cyano at the α-position, 2-(meth)acryloyloxyethyl succinic acid, 2-(meth)acryloyloxyethyl adipic acid, 2-(meth)acryloyloxyethyl phthalic acid, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, 2-(meth)acryloyloxyethyl maleic acid, and 2-(meth)acryloyloxyethyl methyl acrylate. 2-(meth)acryloyloxypropyl succinic acid, 2-(meth)acryloyloxypropyl adipate, 2-(meth)acryloyloxypropyl tetrahydrophthalic acid, 2-(meth)acryloyloxypropyl phthalic acid, 2-(meth)acryloyloxypropyl maleic acid, 2-(meth)acryloyloxybutyl succinic acid, 2-(meth)acryloyloxybutyl adipate, 2-(meth)acryloyloxybutyl hydrophthalic acid, 2-(meth)acryloyloxybutyl phthalic acid, 2-(meth)acryloyloxybutyl maleic acid,
Examples of (meth)acrylic acid esters include monomers having one hydroxyl group at the terminal, which are obtained by adding lactones such as ε-caprolactone, β-propiolactone, γ-butyrolactone, and δ-valerolactone to (meth)acrylic acid, and
Alternatively, examples include (meth)acrylic acid esters and (meth)acrylic acid dimers having one or more ethylenically unsaturated groups and one terminal carboxy group, which are obtained by adding an acid (anhydride) such as succinic acid (anhydride), phthalic acid (anhydride), or maleic acid (anhydride) to a monomer having one terminal hydroxyl group such as hydroxyalkyl (meth)acrylate or a compound having one terminal hydroxyl group such as pentaerythritol tri(meth)acrylate.

Of these, (meth)acrylic acid is particularly preferred from the viewpoint of sensitivity.
A known method can be used to add the unsaturated monobasic acid. For example, the unsaturated monobasic acid can be reacted with an epoxy compound in the presence of an esterification catalyst at a temperature of 50 to 150°C. Examples of the catalyst that can be used here include tertiary phosphines such as triethylphosphine, tributylphosphine, tricyclohexylphosphine, and triphenylphosphine; tertiary amines such as triethylamine, trimethylamine, benzyldimethylamine, and benzyldiethylamine; and quaternary ammonium salts such as tetramethylammonium chloride, tetraethylammonium chloride, and dodecyltrimethylammonium chloride.

The epoxy compound, unsaturated monobasic acid, and catalyst may each be used alone or in combination of two or more thereof.
The amount of the unsaturated monobasic acid used is preferably in the range of 0.5 to 1.2 equivalents, more preferably 0.7 to 1.1 equivalents, per equivalent of the epoxy group of the epoxy compound.
By using the unsaturated monobasic acid in an amount equal to or greater than the lower limit, the amount of unsaturated groups introduced is sufficient, the subsequent reaction with the polybasic acid monoanhydride is also sufficient, and a large amount of epoxy groups tends to be suppressed from remaining.On the other hand, by using the unsaturated monobasic acid in an amount equal to or less than the upper limit, the amount of unsaturated monobasic acid remaining as an unreacted product tends to be suppressed.

Examples of polybasic acid monoanhydrides include one or more selected from the group consisting of monoanhydrides of maleic acid, succinic acid, itaconic acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, pyromellitic acid, methylhexahydrophthalic acid, endomethylenetetrahydrophthalic acid, chlorendic acid, and methyltetrahydrophthalic acid.

Preferred are the anhydrides of maleic acid, succinic acid, itaconic acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, pyromellitic acid, and trimellitic acid. Particularly preferred is the monoanhydride of tetrahydrophthalic acid.

Known techniques can also be used for the addition reaction of polybasic acid monoanhydrides, and the desired product can be obtained by continuing the reaction under conditions similar to those for the addition reaction of unsaturated monobasic acids to epoxy compounds. The amount of polybasic acid monoanhydride added is preferably such that the acid value of the resulting carboxyl group-containing epoxy (meth)acrylate resin is in the range of 10 to 150 mg KOH/g, and more preferably in the range of 20 to 140 mg KOH/g. Setting the amount at or above the lower limit tends to improve alkaline developability. Setting the amount at or below the upper limit tends to improve curability.

The acid value of the epoxy (meth)acrylate resin (A1-1) obtained in this manner is usually 10 mgKOH/g or more, preferably 50 mgKOH/g or more, more preferably 80 mgKOH/g or more, and is preferably 200 mgKOH/g or less, and more preferably 150 mgKOH/g or less. By adjusting the acid value to be equal to or greater than the lower limit, developability tends to be improved. Meanwhile, by adjusting the acid value to be equal to or less than the upper limit, alkali resistance tends to be improved.
The upper and lower limits can be combined arbitrarily. For example, the range is preferably 10 to 200 mgKOH/g, more preferably 50 to 200 mgKOH/g, and even more preferably 80 to 150 mgKOH/g.

The weight average molecular weight (Mw) of the epoxy (meth)acrylate resin (A1-1) measured by gel permeation chromatography (GPC) in terms of polystyrene is preferably 1,000 or more, more preferably 1,500 or more, even more preferably 2,000 or more, and particularly preferably 2,500 or more. It is also preferably 20,000 or less, more preferably 15,000 or less, even more preferably 10,000 or less, even more preferably 8,000 or less, and particularly preferably 7,000 or less. By setting it to the lower limit or more, sensitivity, coating strength, and alkali resistance tend to be improved. By setting it to the upper limit or less, developability and resolubility tend to be improved.
The upper and lower limits can be combined in any way. For example, 1,000 to 20,000 is preferable, 1,000 to 15,000 is more preferable, 1,500 to 10,000 is even more preferable, 2,000 to 8,000 is even more preferable, and 2,500 to 7,000 is particularly preferable.

<Acrylic copolymer resin (A2-1), (A2-2), (A2-3), (A2-4)>
Examples of the acrylic copolymer resin include various polymer compounds described in JP-A-7-207211, JP-A-8-259876, JP-A-10-300922, JP-A-11-140144, JP-A-11-174224, JP-A-2000-56118, JP-A-2003-233179, and JP-A-2007-270147. Preferred examples include resins (A2-1) to (A2-4) below, and among these, resin (A2-1) is particularly preferred.

(A2-1): A resin obtained by adding an unsaturated monobasic acid to at least some of the epoxy groups in a copolymer of an epoxy group-containing (meth)acrylate and another radically polymerizable monomer, or a resin obtained by adding a polybasic acid monoanhydride to at least some of the hydroxyl groups generated by the addition reaction.
(A2-2): A linear alkali-soluble resin containing a carboxy group in the main chain.
(A2-3): A resin obtained by adding an epoxy group-containing unsaturated compound to the carboxy group portion of the resin (A2-2).
(A2-4): (meth)acrylic resin.

From the viewpoint of sensitivity, it is more preferable that the photosensitive resin composition of the present invention contains at least one of (A1-1), (A2-1), and (A2-3) as the alkali-soluble resin containing an ethylenically unsaturated group. From the viewpoint of surface curability, it is particularly preferable that the photosensitive resin composition of the present invention contains the epoxy (meth)acrylate resin (A1-1) as the alkali-soluble resin containing an ethylenically unsaturated group.

The content of the alkali-soluble resin (A) is not particularly limited, but is usually 5% by mass or more, preferably 10% by mass or more, more preferably 15% by mass or more, and usually 90% by mass or less, preferably 70% by mass or less, more preferably 50% by mass or less, even more preferably 30% by mass or less, and particularly preferably 25% by mass or less, based on the total solids content of the photosensitive resin composition. By making the content equal to or greater than the lower limit, the solubility of the unexposed portion in the developer tends to be improved. On the other hand, by making the content equal to or less than the upper limit, excessive penetration of the developer into the exposed portion can be suppressed, and the sharpness and adhesion of the image tend to be improved.
The upper and lower limits can be combined in any manner. For example, 5 to 90 mass% is preferable, 5 to 70 mass% is more preferable, 10 to 50 mass% is even more preferable, 10 to 30 mass% is even more preferable, and 15 to 25 mass% is particularly preferable.
Furthermore, as described above, when the photosensitive resin composition of the present invention contains another alkali-soluble resin as the alkali-soluble resin (A), it is preferable that the other alkali-soluble resin contains at least one of the above-mentioned (A1-1), (A2-1), (A2-2), (A2-3) and (A2-4).
When the photosensitive resin composition of the present invention contains other alkali-soluble resins, the content thereof is preferably 30 mass % or less, more preferably 20 mass % or less, and even more preferably 10 mass % or less, based on the total amount of the alkali-soluble resins (A), from the viewpoint of resist patterning. Alternatively, the photosensitive resin composition may not contain other alkali-soluble resins.

<(B) Photopolymerizable Monomer>
The photosensitive resin composition of the present invention contains a photopolymerizable monomer (B) from the viewpoint of sensitivity and the like.
Examples of the photopolymerizable monomer (B) include compounds having at least one ethylenically unsaturated group in the molecule (hereinafter, sometimes referred to as "ethylenic monomers"). Specific examples include (meth)acrylic acid, (meth)acrylic acid alkyl esters, acrylonitrile, styrene, and esters of carboxylic acids having one ethylenically unsaturated bond with polyhydric or monohydric alcohols.

As the (B) photopolymerizable monomer, it is particularly preferable to use a polyfunctional ethylenic monomer having two or more ethylenically unsaturated groups in one molecule. The number of ethylenically unsaturated groups in the polyfunctional ethylenic monomer is usually two or more, preferably three or more, more preferably four or more, even more preferably five or more, particularly preferably six or more, and is usually ten or less, preferably eight or less. By setting the number to be equal to or greater than the lower limit, the photosensitive resin composition tends to have high sensitivity, and by setting the number to be equal to or less than the upper limit, curing shrinkage during polymerization tends to be small.
The upper and lower limits can be combined in any way. For example, 2 to 10 is preferable, 3 to 10 is more preferable, 4 to 10 is even more preferable, 5 to 8 is even more preferable, and 6 to 8 is particularly preferable.
Examples of polyfunctional ethylenic monomers include esters of aliphatic polyhydroxy compounds and unsaturated carboxylic acids; esters of aromatic polyhydroxy compounds and unsaturated carboxylic acids; and esters obtained by esterification reactions of polyhydric hydroxy compounds such as aliphatic polyhydroxy compounds and aromatic polyhydroxy compounds with unsaturated carboxylic acids and polybasic carboxylic acids.

Examples of esters of aliphatic polyhydroxy compounds and unsaturated carboxylic acids include acrylates of aliphatic polyhydroxy compounds such as ethylene glycol diacrylate, triethylene glycol diacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, and glycerol acrylate; methacrylic acid esters in which the acrylate of these exemplary compounds is replaced with methacrylate; and similarly, itaconic acid esters in which itaconate is replaced with itaconate, crotonate esters in which cronate is replaced with cronate, or maleic acid esters in which maleate is replaced with crotonate.

Examples of esters of aromatic polyhydroxy compounds and unsaturated carboxylic acids include acrylic acid esters and methacrylic acid esters of aromatic polyhydroxy compounds such as hydroquinone diacrylate, hydroquinone dimethacrylate, resorcinol diacrylate, resorcinol dimethacrylate, and pyrogallol triacrylate.
The ester obtained by the esterification reaction of a polybasic carboxylic acid and an unsaturated carboxylic acid with a polyvalent hydroxy compound is not necessarily a single substance, but typical examples include a condensate of acrylic acid, phthalic acid, and ethylene glycol, a condensate of acrylic acid, maleic acid, and diethylene glycol, a condensate of methacrylic acid, terephthalic acid, and pentaerythritol, and a condensate of acrylic acid, adipic acid, butanediol, and glycerin.

Other useful examples of the polyfunctional ethylenic monomer that can be used in the present invention include urethane (meth)acrylates obtained by reacting a polyisocyanate compound with a hydroxyl group-containing (meth)acrylic acid ester or a polyisocyanate compound with a polyol and a hydroxyl group-containing (meth)acrylic acid ester; epoxy acrylates such as addition reaction products of a polyfunctional epoxy compound with a hydroxyl (meth)acrylate or (meth)acrylic acid; acrylamides such as ethylenebisacrylamide; allyl esters such as diallyl phthalate; and vinyl group-containing compounds such as divinyl phthalate.
These may be used alone or in combination of two or more.

The content of the (B) photopolymerizable monomer is not particularly limited, but is usually 90% by mass or less, preferably 70% by mass or less, more preferably 50% by mass or less, even more preferably 30% by mass or less, even more preferably 20% by mass or less, and particularly preferably 10% by mass or less, based on the total solids content of the photosensitive resin composition. When the content of the photopolymerizable monomer is equal to or less than the upper limit, the permeability of the developer into the exposed area tends to be adequate, and a good image tends to be obtained. The content of the photopolymerizable monomer (b) is usually 1% by mass or more, preferably 5% by mass or more. When the content is equal to or greater than the lower limit, the photocuring by ultraviolet irradiation tends to be improved and the alkali developability also tends to be good.
The upper and lower limits can be combined in any manner. For example, 1 to 90 mass% is preferable, 1 to 70 mass% is more preferable, 1 to 50 mass% is even more preferable, 5 to 30 mass% is even more preferable, 5 to 20 mass% is particularly preferable, and 5 to 10 mass% is particularly preferable.

<(C) Photopolymerization initiator>
The photosensitive resin composition of the present invention contains (C) a photopolymerization initiator. The photopolymerization initiator is a component that directly absorbs light, causes a decomposition reaction or a hydrogen abstraction reaction, and generates polymerization-active radicals. If necessary, an additive such as a sensitizing dye may be added to the photopolymerization initiator.

Examples of photopolymerization initiators include metallocene compounds, including titanocene compounds, described in JP 59-152396 A and JP 61-151197 A; hexaarylbiimidazole derivatives, described in JP 2000-56118 A; halomethylated oxadiazole derivatives, halomethyl-s-triazine derivatives, N-aryl-α-amino acids such as N-phenylglycine, N-aryl-α-amino acid salts, N-aryl-α-amino acid esters, and other radical activators, α-aminoalkylphenone derivatives, described in JP 10-39503 A; and oxime ester derivatives, described in JP 2000-80068 A and JP 2006-36750 A.

Examples of titanocene derivatives include dicyclopentadienyltitanium dichloride, dicyclopentadienyltitanium bisphenyl, dicyclopentadienyltitanium bis(2,3,4,5,6-pentafluorophenyl-1-yl), dicyclopentadienyltitanium bis(2,3,5,6-tetrafluorophenyl-1-yl), dicyclopentadienyltitanium bis(2,4,6-trifluorophenyl-1-yl), dicyclopentadienyltitanium titanium di(2,6-difluorophenyl-1-yl), dicyclopentadienyltitanium di(2,4-difluorophenyl-1-yl), di(methylcyclopentadienyl)titanium bis(2,3,4,5,6-pentafluorophenyl-1-yl), di(methylcyclopentadienyl)titanium bis(2,6-difluorophenyl-1-yl), and dicyclopentadienyltitanium [2,6-difluoro-3-(pyrro-1-yl)-phenyl-1-yl].

Examples of biimidazole derivatives include 2-(2'-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(2'-chlorophenyl)-4,5-bis(3'-methoxyphenyl)imidazole dimer, 2-(2'-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(2'-methoxyphenyl)-4,5-diphenylimidazole dimer, and (4'-methoxyphenyl)-4,5-diphenylimidazole dimer.

Examples of halomethylated oxadiazole derivatives include 2-trichloromethyl-5-(2'-benzofuryl)-1,3,4-oxadiazole, 2-trichloromethyl-5-[β-(2'-benzofuryl)vinyl]-1,3,4-oxadiazole, 2-trichloromethyl-5-[β-(2'-(6"-benzofuryl)vinyl)]-1,3,4-oxadiazole, and 2-trichloromethyl-5-furyl-1,3,4-oxadiazole.

Examples of halomethyl-s-triazine derivatives include 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-ethoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, and 2-(4-ethoxycarbonylnaphthyl)-4,6-bis(trichloromethyl)-s-triazine.

Examples of α-aminoalkylphenone derivatives include 2-methyl-1[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one, 4-dimethylaminoethyl benzoate, 4-dimethylaminoisoamyl benzoate, 4-diethylaminoacetophenone, 4-dimethylaminopropiophenone, 2-ethylhexyl-1,4-dimethylaminobenzoate, 2,5-bis(4-diethylaminobenzal)cyclohexanone, 7-diethylamino-3-(4-diethylaminobenzoyl)coumarin, and 4-(diethylamino)chalcone.

As photopolymerization initiators, oxime derivatives (oxime ester compounds and ketoxime ester compounds) are particularly useful in terms of sensitivity. Among oxime derivatives, oxime ester compounds are preferred from the standpoint of adhesion to the substrate. When using alkali-soluble resins containing phenolic hydroxyl groups, sensitivity may be disadvantageous.

Oxime ester-based photopolymerization initiators possess a structure that combines UV absorption, light energy transmission, and radical generation. This allows for high sensitivity even in small amounts and stability against thermal reactions, making it possible to design highly sensitive photosensitive resin compositions with small amounts. In particular, from the perspective of light absorption for the i-line (365 nm) of the exposure light source, oxime ester-based compounds containing an optionally substituted carbazolyl group (a group containing an optionally substituted carbazole ring) are more preferred, as this structural characteristic is well expressed. Currently, the market demands thin black matrices with high light blocking properties, and pigment concentrations are increasing. Under these circumstances, these compounds are particularly effective.

Examples of oxime ester compounds include compounds containing a structural moiety represented by the following general formula (22), and preferably oxime ester compounds represented by the following general formula (23):

In the above formula (22), R ²² represents an alkanoyl group having 2 to 12 carbon atoms, a heteroarylalkanoyl group having 1 to 20 carbon atoms, an alkenoyl group having 3 to 25 carbon atoms, a cycloalkanoyl group having 3 to 8 carbon atoms, an alkoxycarbonylalkanoyl group having 3 to 20 carbon atoms, a phenoxycarbonylalkanoyl group having 8 to 20 carbon atoms, a heteroaryloxycarbonylalkanoyl group having 3 to 20 carbon atoms, an aminoalkylcarbonyl group having 2 to 10 carbon atoms, an aryloyl group having 7 to 20 carbon atoms, a heteroaryloyl group having 1 to 20 carbon atoms, an alkoxycarbonyl group having 2 to 10 carbon atoms, or an aryloxycarbonyl group having 7 to 20 carbon atoms, each of which may be substituted.

In formula (23), R ^21a represents hydrogen, or an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 25 carbon atoms, a heteroarylalkyl group having 1 to 20 carbon atoms, an alkoxycarbonylalkyl group having 3 to 20 carbon atoms, a phenoxycarbonylalkyl group having 8 to 20 carbon atoms, a heteroaryloxycarbonylalkyl group or a heteroarylthioalkyl group having 1 to 20 carbon atoms, an aminoalkyl group having 1 to 20 carbon atoms, an alkanoyl group having 2 to 12 carbon atoms, an alkenoyl group having 3 to 25 carbon atoms, a cycloalkanoyl group having 3 to 8 carbon atoms, an aryloyl group having 7 to 20 carbon atoms, a heteroaryloyl group having 1 to 20 carbon atoms, an alkoxycarbonyl group having 2 to 10 carbon atoms, an aryloxycarbonyl group having 7 to 20 carbon atoms, or a cycloalkylalkyl group having 1 to 10 carbon atoms, each of which may be substituted.
R ^21b represents any substituent containing an aromatic ring or a heteroaromatic ring.

R ^21a may form a ring together with R ^21b , and the linking group may be an alkylene group having 1 to 10 carbon atoms, a polyethylene group (-(CH=CH) _r -), a polyethynylene group (-(C≡C) _r -), or a group formed by combining these, each of which may have a substituent (where r is an integer of 0 to 3).
R ^22a represents the same group as R ²² in the above formula (22).
R ²² in the general formula (22) and R ^22a in the general formula (23) are preferably alkanoyl groups having 2 to 12 carbon atoms, heteroarylalkanoyl groups having 1 to 20 carbon atoms, and cycloalkanoyl groups having 3 to 8 carbon atoms.

R ^21a in the above general formula (23) is preferably an unsubstituted straight-chain alkyl group or cycloalkylalkyl group such as a methyl group, an ethyl group, or a propyl group, or a propyl group substituted with an N-acetyl-N-acetoxyamino group.
Furthermore, R ^21b in the above general formula (23) is preferably a carbazolyl group which may be substituted, a thioxanthonyl group which may be substituted, or a phenyl sulfide group which may be substituted.

As the oxime ester compound photopolymerization initiator, those in which R ^21b in the above general formula (23) is an optionally substituted carbazolyl group are more preferred for the reasons mentioned above. Furthermore, carbazole groups having at least one group selected from the group consisting of an optionally substituted aryl group having 6 to 25 carbon atoms, an optionally substituted arylcarbonyl group having 7 to 25 carbon atoms, an optionally substituted heteroaryl group having 5 to 25 carbon atoms, an optionally substituted heteroarylcarbonyl group having 6 to 25 carbon atoms, and a nitro group are preferred. Carbazolyl groups having at least one group selected from the group consisting of a benzoyl group, a toluoyl group, a naphthoyl group, a thienylcarbonyl group, and a nitro group are particularly preferred. Furthermore, it is desirable for these groups to be bonded to the 3-position of the carbazolyl group.

Commercially available photopolymerization initiators based on such oxime ester compounds include OXE-02 manufactured by BASF, and TR-PBG-304 and TR-PBG-314 manufactured by Changzhou Strong Electronics Co., Ltd.

Specific examples of photopolymerization initiators for oxime ester compounds suitable for use in the present invention include the compounds exemplified below, but are not limited to these compounds.

Examples of ketoxime ester compounds include compounds containing a structural moiety represented by the following general formula (24), and preferably ketoxime ester compounds represented by the following general formula (25):

In the above general formula (24), R ²⁴ has the same meaning as R 22 in the above general formula (22).

In the general formula (25), R ^23a represents a phenyl group, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 25 carbon atoms, a heteroarylalkyl group having 1 to 20 carbon atoms, an alkoxycarbonylalkyl group having 3 to 20 carbon atoms, a phenoxycarbonylalkyl group having 8 to 20 carbon atoms, an alkylthioalkyl group having 2 to 20 carbon atoms, a heteroaryloxycarbonylalkyl group or a heteroarylthioalkyl group having 1 to 20 carbon atoms, an aminoalkyl group having 1 to 20 carbon atoms, an alkanoyl group having 2 to 12 carbon atoms, an alkenoyl group having 3 to 25 carbon atoms, a cycloalkanoyl group having 3 to 8 carbon atoms, an aryloyl group having 7 to 20 carbon atoms, a heteroaryloyl group having 1 to 20 carbon atoms, an alkoxycarbonyl group having 2 to 10 carbon atoms, an aryloxycarbonyl group having 7 to 20 carbon atoms, or a cycloalkylalkyl group having 1 to 10 carbon atoms, each of which may be substituted.

R ^23b represents any substituent containing an aromatic ring or a heteroaromatic ring.
R ^23a may form a ring together with R ^23b , and the linking group may be an alkylene group having 1 to 10 carbon atoms, a polyethylene group (-(CH=CH) _r -), a polyethynylene group (-(C≡C) _r -), or a group formed by combining these, each of which may have a substituent (where r is an integer of 0 to 3).

R ^24a represents an alkanoyl group having 2 to 12 carbon atoms, an alkenoyl group having 3 to 25 carbon atoms, a cycloalkanoyl group having 4 to 8 carbon atoms, a benzoyl group having 7 to 20 carbon atoms, a heteroaryloyl group having 3 to 20 carbon atoms, an alkoxycarbonyl group having 2 to 10 carbon atoms, an aryloxycarbonyl group having 7 to 20 carbon atoms, a heteroaryl group having 2 to 20 carbon atoms, or an alkylaminocarbonyl group having 2 to 20 carbon atoms, each of which may be substituted.
R ²⁴ in the general formula (24) and R ^24a in the general formula (25) are preferably an alkanoyl group having 2 to 12 carbon atoms, a heteroarylalkanoyl group having 1 to 20 carbon atoms, a cycloalkanoyl group having 3 to 8 carbon atoms, or an aryloyl group having 7 to 20 carbon atoms.

R ^23a in the above general formula (25) is preferably an unsubstituted ethyl group, propyl group, or butyl group, or an ethyl group or propyl group substituted with a methoxycarbonyl group.
Furthermore, R ^23b in the above general formula (25) is preferably a carbazoyl group which may be substituted, or a phenyl sulfide group which may be substituted.
Specific examples of ketoxime ester compounds suitable for the present invention include the compounds exemplified below, but the present invention is not limited to these compounds.

Commercially available photopolymerization initiators based on such ketoxime ester compounds include OXE-01 manufactured by BASF and TR-PBG-305 manufactured by Changzhou Strong Electronics Co., Ltd.

These oxime and ketoxime ester compounds are known per se and are one type of the series of compounds described in, for example, Japanese Patent Application Laid-Open Nos. 2000-80068 and 2006-36750.
The photopolymerization initiators may be used alone or in combination of two or more.

Other examples include benzoin alkyl ethers such as benzoin methyl ether, benzoin phenyl ether, benzoin isobutyl ether, and benzoin isopropyl ether; anthraquinone derivatives such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, and 1-chloroanthraquinone; benzophenone derivatives such as benzophenone, Michler's ketone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 2-chlorobenzophenone, 4-bromobenzophenone, and 2-carboxybenzophenone; 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, α-hydroxy-2-methylphenylpropanone, 1-hydroxy-1-methylethyl-(p-isopropyl phenyl)propanone, and the like. acetophenone derivatives such as 1-(4-phenyl) ketone, 1-hydroxy-1-(p-dodecylphenyl) ketone, 2-methyl-(4'-methylthiophenyl)-2-morpholino-1-propanone, and 1,1,1-trichloromethyl-(p-butylphenyl) ketone; thioxanthone derivatives such as thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, and 2,4-diisopropylthioxanthone; benzoate derivatives such as ethyl p-dimethylaminobenzoate and ethyl p-diethylaminobenzoate; acridine derivatives such as 9-phenylacridine and 9-(p-methoxyphenyl)acridine; phenazine derivatives such as 9,10-dimethylbenzphenazine; and anthrone derivatives such as benzanthrone.
Among these photopolymerization initiators, oxime ester derivatives are particularly preferred for the reasons mentioned above.

<Sensitizing dye>
The photopolymerization initiator may be used in combination with a sensitizing dye according to the wavelength of the image exposure light source, if necessary, for the purpose of increasing sensitivity. Examples of these sensitizing dyes include xanthene dyes described in JP-A-4-221958 and JP-A-4-219756, coumarin dyes having a heterocycle described in JP-A-3-239703 and JP-A-5-289335, 3-ketocoumarin compounds described in JP-A-3-239703 and JP-A-5-289335, pyrromethene dyes described in JP-A-6-19240, and others, such as those described in JP-A-47-2528 and JP-A-54-155292. [0044] Examples of dyes having a dialkylaminobenzene skeleton include those described in JP-B No. 45-37377, JP-A No. 48-84183, JP-A No. 52-112681, JP-A No. 58-15503, JP-A No. 60-88005, JP-A No. 59-56403, JP-A No. 2-69, JP-A No. 57-168088, JP-A No. 5-107761, JP-A No. 5-210240, and JP-A No. 4-288818.

Among these sensitizing dyes, preferred are amino group-containing sensitizing dyes, and more preferred are compounds having an amino group and a phenyl group in the same molecule. Examples include benzophenone compounds such as 4,4'-dimethylaminobenzophenone, 4,4'-diethylaminobenzophenone, 2-aminobenzophenone, 4-aminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, and 3,4-diaminobenzophenone; 2-(p-dimethylaminophenyl)benzoxazole, 2-(p-diethylaminophenyl)benzoxazole, 2-(p-dimethylaminophenyl)benzo[4,5]benzoxazole, 2-(p-dimethylaminophenyl)benzo[6,7]benzoxazole, 2,5-bis(p-diethylaminophenyl)1,3,4-oxazole, and 2-(p-dimethylaminophenyl)benzo[4,5]benzoxazole. More preferred are p-dialkylaminophenyl group-containing compounds such as 4,4'-dialkylaminophenyl)benzothiazole, 2-(p-diethylaminophenyl)benzothiazole, 2-(p-dimethylaminophenyl)benzimidazole, 2-(p-diethylaminophenyl)benzimidazole, 2,5-bis(p-diethylaminophenyl)1,3,4-thiadiazole, (p-dimethylaminophenyl)pyridine, (p-diethylaminophenyl)pyridine, (p-dimethylaminophenyl)quinoline, (p-diethylaminophenyl)quinoline, (p-dimethylaminophenyl)pyrimidine, and (p-diethylaminophenyl)pyrimidine, and 4,4'-dialkylaminobenzophenone is particularly preferred.
The sensitizing dyes may be used alone or in combination of two or more.

The content of the (C) photopolymerization initiator is not particularly limited, but is usually 1% by mass or more, preferably 2% by mass or more, more preferably 3% by mass or more, and even more preferably 4% by mass or more, relative to the total solid content of the photosensitive resin composition, and is usually 30% by mass or less, preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, and particularly preferably 8% by mass or less. By making it equal to or greater than the lower limit, sensitivity tends to be improved. On the other hand, by making it equal to or less than the upper limit, the solubility of the unexposed portion in the developer tends to be improved.
The upper and lower limits can be combined in any manner. For example, the content is preferably 1 to 30% by mass, more preferably 1 to 20% by mass, even more preferably 2 to 15% by mass, even more preferably 3 to 10% by mass, and particularly preferably 4 to 8% by mass.

When a sensitizing dye is used, the proportion of the sensitizing dye in the photosensitive resin composition is typically 0 to 20% by mass, preferably 0 to 15% by mass, and more preferably 0 to 10% by mass, of the total solids content in the photosensitive resin composition.

<(D) Coloring material>
When the photosensitive resin composition of the present invention is used for forming pixels, black matrices, colored spacers, etc. of a color filter, it preferably contains (D) a colorant. The colorant refers to a material that colors the photosensitive resin composition of the present invention. As the colorant, dyes and pigments can be used, but pigments are preferred from the viewpoints of heat resistance, light resistance, etc.

Pigments of various colors can be used, including blue, green, red, yellow, purple, orange, brown, and black. In addition to organic pigments with different structures, such as azo, phthalocyanine, quinacridone, benzimidazolone, isoindolinone, dioxazine, indanthrene, and perylene, various inorganic pigments can also be used.

Specific examples of pigments that can be used in the present invention are shown below by pigment number. Note that terms such as "C.I. Pigment Red 2" listed below refer to the Color Index (C.I.).
Examples of red pigments include C.I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 14, 15, 16, 17, 21, 22, 23, 31, 32, 37, 38, 41, 47, 48, 48:1, 48:2, 48:3, 48:4, 49, 49:1, 49:2, 50:1, 52:1, 52:2, 53, 53:1, 53:2, 53:3, 57, 57:1, 57:2, 58:4, 60, 63, 63:1, 63:2, 64, 64:1, 68, 69, 81, 81:1, 81:2, 81:3, 81:4, 83, 88, 90:1, 101, 101:1, 104, 108, 108:1, 109, 112, 113, 114, 122, 123, 144, 146, 147, 149, 151, 166 , 168, 169, 170, 172, 173, 174, 175, 176, 177, 178, 179, 181, 184, 185, 187, 188, 190, 193, 194, 200, 202, 206, 207, 208, 209, 210, 214, 216, 220, 221, 224, 230, 231, 232, 233, 235, 236, 237, 238, 239, 242, 243, 245, 247, 249, 250, 251, 253, 254, 255, 256, 257, 258, 259, 260, 262, 263, 264, 265, 266, 267, 268, 269, 270, 271, 272, 273, 274, 275, 276. Among these, preferred are C.I. Pigment Red 48:1, 122, 168, 177, 202, 206, 207, 209, 224, 242, 254, and more preferred are C.I. Pigment Red 177, 209, 224, 254.

Examples of blue pigments include C.I. Pigment Blue 1, 1:2, 9, 14, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 17, 19, 25, 27, 28, 29, 33, 35, 36, 56, 56:1, 60, 61, 61:1, 62, 63, 66, 67, 68, 71, 72, 73, 74, 75, 76, 78, and 79. Of these, C.I. Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, 15:6, and 60 are preferred, and C.I. Pigment Blue 15:6 and 60 are more preferred.

Examples of green pigments include C.I. Pigment Green 1, 2, 4, 7, 8, 10, 13, 14, 15, 17, 18, 19, 26, 36, 45, 48, 50, 51, 54, 55, and 58. Of these, C.I. Pigment Green 7, 36, and 58 are preferred.

Examples of yellow pigments include C.I. Pigment Yellow 1, 1:1, 2, 3, 4, 5, 6, 9, 10, 12, 13, 14, 16, 17, 24, 31, 32, 34, 35, 35:1, 36, 36:1, 37, 37:1, 40, 41, 42, 43, 48, 53, 55, 61, 62, 62:1, 63, 65, 73, 74, 75, 81, 83, 87, 93, 94, 95, 97, 100, 101, 104, 105, 108, 109, 110, 111, 116, 117, 119, 120, 126, 127, 127:1, 128, 129, 133, 134, 136, 13 8, 139, 142, 147, 148, 150, 151, 153, 154, 155, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 172, 173, 174, 175, 176, 180, 181, 182, 183, 184, 185, 188, 189, 190, 191, 191:1, 192, 193, 194, 195, 196, 197, 198, 199, 200, 202, 203, 204, 205, 206, 207, 208 can be mentioned. Among these, C.I. Pigment Yellow 83, 117, 129, 138, 139, 150, 154, 155, 180, and 185, and more preferably C.I. Pigment Yellow 83, 138, 139, 150, and 180.

Examples of orange pigments include C.I. Pigment Orange 1, 2, 5, 13, 16, 17, 19, 20, 21, 22, 23, 24, 34, 36, 38, 39, 43, 46, 48, 49, 61, 62, 64, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 77, 78, and 79. Of these, C.I. Pigment Orange 38, 64, and 71 are preferred.

Examples of purple pigments include C.I. Pigment Violet 1, 1:1, 2, 2:2, 3, 3:1, 3:3, 5, 5:1, 14, 15, 16, 19, 23, 25, 27, 29, 31, 32, 37, 39, 42, 44, 47, 49, and 50. Of these, C.I. Pigment Violet 19, 23, and 29 are preferred, and C.I. Pigment Violet 23 and 29 are even more preferred.

When the photosensitive resin composition of the present invention is a photosensitive resin composition for a resin black matrix of a color filter, a black colorant can be used as the colorant (D). The black colorant may be a single black colorant or a mixture of red, green, blue, and other colorants. Furthermore, these colorants can be appropriately selected from inorganic or organic pigments and dyes.
Examples of colorants that can be mixed to prepare black colorants include Victoria Pure Blue (42595), Auramine O (41000), Catilon Brilliant Flavin (Basic 13), Rhodamine 6GCP (45160), Rhodamine B (45170), Safranin OK70:100 (50240), Erioglaucine X (42080), No. 120/Lionol Yellow (21090), Lionol Yellow GRO (21090), Shimler Fast Yellow 8GF (21105), Benzidine Yellow 4T-564D (21095), Shimler First Red 4015 (12355), Lionol Red 7B4401 (15850), Firstgen Blue TGR-L (74160), Lionol Blue SM (26150), Lionol Blue ES (Pigment Blue 15:6), Lionogen Red GD (Pigment Red 168), Lionol Green 2YS (Pigment Green 36) (Note that the numbers in parentheses above refer to the Color Index (C.I.)).

Other pigments that can be mixed and used are listed by C.I. number, for example: C.I. Yellow Pigments 20, 24, 86, 93, 109, 110, 117, 125, 137, 138, 147, 148, 153, 154, 166; C.I. Orange Pigments 36, 43, 51, 55, 59, 61, 64; C.I. Red Pigments 9, 97, 122, 123, 149, 168, 177, 180, 192, 215, 216, 217, 220, 223, 224, 226, 227, 228, 240, 254; C.I. Violet Pigments 19, 23, 29, 30, 37, 40, 50; C.I. Examples of the pigments include C.I. blue pigments 15, 15:1, 15:4, 22, 60, and 64, C.I. green pigment 7, and C.I. brown pigments 23, 25, and 26.

Examples of black coloring materials that can be used alone include carbon black, acetylene black, lamp black, bone black, graphite, iron black, aniline black, cyanine black, titanium black, perylene black, and lactam black.
When a black coloring material is used among these coloring materials (D), carbon black is preferred from the viewpoint of light-shielding rate and image characteristics. Examples of carbon black include the following carbon blacks.

Mitsubishi Chemical Corporation: MA7, MA77, MA8, MA11, MA100, MA100R, MA220, MA230, MA600, #5, #10, #20, #25, #30, #32, #33, #40, #44, #45, #47, #50, #52, #55, #650, #750, #850, #950, # 960, #970, #980, #990, #1000, #2200, #2300, #2350, #2400, #2600, #3050, #3150, #3250, #3600, #3750, #3950, #4000, #4010, OIL7B, OIL9B, OIL11B, OIL30B, OIL31B
Degussa: Printex (registered trademark; the same applies hereinafter) 3, Printex3OP, Printex30, Printex30OP, Printex40, Printex45, Printex55, Printex60, Printex75, Printex80, Printex85, Printex90, Printex A, Printex L, Printex G, Printex P, Printex U, Printex V, PrintexG, SpecialBlack550, SpecialBlack350, SpecialBlack250, Sp specialBlack100, SpecialBlack6, SpecialBlack5, SpecialBlack4, Color Black FW1, Color Black FW2, Color Black FW2V, Color Black FW18, Color Black FW18, Color Black FW200, Color Black S160, Color Black S170
Cabot Corporation: Monarch (registered trademark; the same applies hereinafter) 120, Monarch 280, Monarch 460, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1300, Monarch 1400, Monarch 4630, REGAL (registered trademark; the same applies hereinafter) 99, REGAL 99R, REGAL 415, REGAL 415R, REGAL 250, REGAL 250R, REGAL 330, REGAL 400R, REGAL 55R0, REGAL 660R, BLACK PEARLS 480, PEARLS 130, VULCAN (registered trademark) XC72R, ELFTEX®-8
Manufactured by Biller: RAVEN11, RAVEN14, RAVEN15, RAVEN16, RAVEN22, RAVEN30, RAVEN35, RAVEN40, RAVEN410, RAVEN420, RAVEN450, RAVEN500, RAVEN780, RAVEN850, RAVEN890H, RAVEN1000, RAVE N1020, RAVEN1040, RAVEN1060U, RAVEN1080U, RAVEN1170, RAVEN1190U, RAVEN1250, RAVEN 1500, RAVEN2000, RAVEN2500U, RAVEN3500, RAVEN5000, RAVEN5250, RAVEN5750, RAVEN7000

Other examples of black pigments include titanium black, aniline black, iron oxide-based black pigments, and a mixture of three organic pigments (red, green, and blue) that can be used as a black pigment.

Pigments that can be used include, for example, barium sulfate, lead sulfate, titanium oxide, yellow lead, red iron oxide, and chromium oxide. Multiple types of these pigments can also be used in combination. For example, to adjust the chromaticity, a green pigment can be used in combination with a yellow pigment, or a blue pigment can be used in combination with a purple pigment.

The average particle size of the pigment is not particularly limited as long as it can produce the desired color when used in a colored layer of a color filter, and although it varies depending on the type of pigment used, it is preferably in the range of 10 to 100 nm, and more preferably in the range of 10 to 70 nm. When the average particle size of the pigment is in the above range, the color characteristics of a liquid crystal display device manufactured using the photosensitive resin composition of the present invention tend to be of high quality.
The average particle size of carbon black is preferably 60 nm or less, more preferably 50 nm or less, and preferably 20 nm or more, for example, 20 to 50 nm is preferred, and 20 to 60 nm is more preferred. By setting the average particle size to the upper limit or less, scattering tends to be reduced, and deterioration of color properties such as light-blocking properties and contrast tends to be suppressed. Furthermore, by setting the average particle size to the lower limit or more, the amount of dispersant does not need to be excessively large, and dispersibility tends to be improved.
The average particle size of the above pigments, including carbon black, can be determined by directly measuring the size of primary particles from an electron microscope photograph. Specifically, the minor axis and major axis of each primary particle are measured, and the average is taken as the particle size of that particle. Next, the volume (mass) of each of 100 or more particles is determined by approximating it to a rectangular parallelepiped of the determined particle size, and the volume-average particle size is determined, which is taken as the average particle size. The same results can be obtained using either a transmission electron microscope (TEM) or a scanning electron microscope (SEM).

When the photosensitive resin composition of the present invention contains a colorant (D), it is preferable that the colorant contains at least a pigment, but other dyes may also be used in combination as long as they do not affect the effects of the present invention. Examples of dyes that can be used in combination include azo dyes, anthraquinone dyes, phthalocyanine dyes, quinoneimine dyes, quinoline dyes, nitro dyes, carbonyl dyes, and methine dyes.

Examples of azo dyes include C.I. Acid Yellow 11, C.I. Acid Orange 7, C.I. Acid Red 37, C.I. Acid Red 180, C.I. Acid Blue 29, C.I. Direct Red 28, C.I. Direct Red 83, C.I. Direct Yellow 12, C.I. Direct Orange 26, C.I. Direct Green 28, C.I. Direct Green 59, C.I. Reactive Yellow 2, C.I. Reactive Red 17, C.I. Reactive Red 120, C.I. Reactive Black 5, C.I. Disperse Orange 5, C.I. Disperse Red 58, C.I. Disperse Blue 165, C.I. Basic Blue 41, C.I. Basic Red 18, C.I. Examples of suitable pigments include C.I. Mordant Red 7, C.I. Mordant Yellow 5, and C.I. Mordant Black 7.

Examples of anthraquinone dyes include C.I. Vat Blue 4, C.I. Acid Blue 40, C.I. Acid Green 25, C.I. Reactive Blue 19, C.I. Reactive Blue 49, C.I. Disperse Red 60, C.I. Disperse Blue 56, and C.I. Disperse Blue 60.
In addition, examples of phthalocyanine dyes include C.I. Pad Blue 5, quinoneimine dyes include C.I. Basic Blue 3 and C.I. Basic Blue 9, quinoline dyes include C.I. Solvent Yellow 33, C.I. Acid Yellow 3, and C.I. Disperse Yellow 64, and nitro dyes include C.I. Acid Yellow 1, C.I. Acid Orange 3, and C.I. Disperse Yellow 42.

When the photosensitive resin composition of the present invention contains a colorant (D), the content of the colorant (D) can be selected from the range of usually 1 to 70% by mass based on the total solid content of the photosensitive resin composition. Within this range, the content is preferably 20% by mass or more, more preferably 30% by mass or more, particularly preferably 40% by mass or more, and more preferably 60% by mass or less.
The upper and lower limits can be combined in any manner. For example, the content is preferably 1 to 70% by mass, more preferably 20 to 70% by mass, even more preferably 30 to 60% by mass, and particularly preferably 40 to 60% by mass.

The photosensitive resin composition of the present invention can be used for a variety of purposes, as described below. When used to form a black matrix, the (D) colorant can be a black colorant such as the aforementioned carbon black or titanium black, or a mixture of multiple non-black colorants can be used to create a black color. Among these, carbon black is particularly preferred from the standpoints of dispersion stability and light-blocking properties.

When the photosensitive resin composition of the present invention is used to form a black matrix, it is necessary to increase the concentration of the black colorant to increase the light-shielding effect. From this viewpoint, the content of the black colorant is 40% by mass or more, preferably 45% by mass or more, and more preferably 50% by mass or more, based on the total solid content of the photosensitive resin composition. Furthermore, from the viewpoint of image forming performance, it is preferably 70% by mass or less, more preferably 65% by mass or less.
The upper and lower limits can be combined in any desired manner. For example, the content is preferably 40 to 70% by mass, more preferably 45 to 70% by mass, and even more preferably 50 to 65% by mass.

When the photosensitive resin composition of the present invention contains a (D) colorant, the content of the (D) colorant is usually 20 parts by mass or more, preferably 30 parts by mass or more, more preferably 40 parts by mass or more, even more preferably 60 parts by mass or more, still more preferably 80 parts by mass or more, particularly preferably 120 parts by mass or more, and most preferably 160 parts by mass or more, per 100 parts by mass of the (A) alkali-soluble resin, and is usually 500 parts by mass or less, preferably 300 parts by mass or less, more preferably 280 parts by mass or less. By setting the content of the (D) colorant at or above the lower limit, it is easy to suppress a decrease in the solubility of the unexposed area in the developer. On the other hand, by setting it at or below the upper limit, it is easy to obtain a desired image film thickness.
The upper and lower limits can be combined in any desired manner. For example, 20 to 500 parts by mass is preferable, 30 to 500 parts by mass is more preferable, 40 to 500 parts by mass is even more preferable, 60 to 300 parts by mass is even more preferable, 80 to 300 parts by mass is particularly preferable, 120 to 280 parts by mass is particularly preferable, and 160 to 280 parts by mass is most preferable.

<Dispersant>
When the photosensitive resin composition of the present invention contains a colorant (D), it is important to finely disperse the colorant and stabilize the dispersed state in order to ensure stable quality, and therefore it is preferable that the composition further contains a dispersant.
As the dispersant, a polymer dispersant having a functional group is preferred, and furthermore, from the viewpoint of dispersion stability, a polymer dispersant having a functional group such as a carboxyl group; a phosphate group; a sulfonic acid group; or a base thereof; a primary, secondary or tertiary amino group; a quaternary ammonium base; or a group derived from a nitrogen-containing heterocycle such as pyridine, pyrimidine or pyrazine is preferred. Among these, a polymer dispersant having a basic functional group such as a primary, secondary or tertiary amino group; a quaternary ammonium base; or a group derived from a nitrogen-containing heterocycle such as pyridine, pyrimidine or pyrazine is particularly preferred. By using a polymer dispersant having such a basic functional group, dispersibility tends to be improved.

Examples of polymeric dispersants include urethane-based dispersants, acrylic-based dispersants, polyethyleneimine-based dispersants, polyallylamine-based dispersants, dispersants consisting of monomers and macromonomers with amino groups, polyoxyethylene alkyl ether-based dispersants, polyoxyethylene diester-based dispersants, polyether phosphate-based dispersants, polyester phosphate-based dispersants, sorbitan aliphatic ester-based dispersants, and aliphatic-modified polyester-based dispersants.

Specific examples of such dispersants include, by trade name, EFKA (registered trademark, manufactured by EFKA Chemicals BV), Disperbyk (registered trademark, manufactured by BYK-Chemie), Disparlon (registered trademark, manufactured by Kusumoto Chemicals Co., Ltd.), SOLSPERSE (registered trademark, manufactured by Lubrizol Corporation), KP (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow or Florene (registered trademark, manufactured by Kyoeisha Chemical Co., Ltd.), and AJISPER (registered trademark, manufactured by Ajinomoto Fine-Techno Co., Inc.).
These polymer dispersants may be used alone or in combination of two or more.

Of these, from the standpoints of adhesion and linearity, it is preferable that the dispersant contains a urethane-based polymer dispersant and/or an acrylic-based polymer dispersant having a basic functional group, and it is more preferable that the dispersant contains a urethane-based polymer dispersant in terms of adhesion. Furthermore, from the standpoints of dispersibility and storage stability, it is preferable to use a polymer dispersant that has a basic functional group and polyester and/or polyether bonds.

The weight average molecular weight (Mw) of the polymer dispersant is usually 700 or more, preferably 1,000 or more, and usually 100,000 or less, preferably 50,000 or less, and more preferably 30,000 or less. By setting the weight average molecular weight (Mw) to the aforementioned upper limit or less, alkaline developability tends to be good even when the pigment concentration is high.
The upper and lower limits can be combined in any manner. For example, 700 to 100,000 is preferable, 700 to 50,000 is more preferable, and 1,000 to 30,000 is even more preferable.
Examples of urethane-based and acrylic-based polymer dispersants include the Disperbyk 160 to 167 and 182 series (all urethane-based), and Disperbyk 2000 and 2001 (all acrylic-based) (all manufactured by BYK-Chemie). Particularly preferred examples of the urethane-based polymer dispersants having a basic functional group and a polyester and/or polyether bond and a weight-average molecular weight of 30,000 or less include Disperbyk 167 and 182.

<Urethane-based polymer dispersant>
Specific examples of chemical structures preferred for urethane-based polymer dispersants include dispersion resins with a weight average molecular weight of 1,000 to 200,000, which are obtained by reacting a polyisocyanate compound, a compound having one or two hydroxyl groups in the molecule and a number average molecular weight of 300 to 10,000, and a compound having an active hydrogen and a tertiary amino group in the same molecule.

Examples of the above polyisocyanate compounds include aromatic diisocyanates such as paraphenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, naphthalene-1,5-diisocyanate, and tolidine diisocyanate; aliphatic diisocyanates such as hexamethylene diisocyanate, lysine methyl ester diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and dimer acid diisocyanate; isophorone diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), and ω,ω'-dimethyl diisocyanate. Examples of suitable polyisocyanates include alicyclic diisocyanates such as cyclohexane, aliphatic diisocyanates having an aromatic ring such as xylylene diisocyanate and α,α,α',α'-tetramethylxylylene diisocyanate, lysine ester triisocyanate, 1,6,11-undecane triisocyanate, 1,8-diisocyanate-4-isocyanatomethyloctane, 1,3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate, tris(isocyanatophenylmethane), tris(isocyanatophenyl)thiophosphate, and their trimers, water adducts, and polyol adducts. Preferred polyisocyanates are trimers of organic diisocyanates, and most preferred are the trimer of tolylene diisocyanate and the trimer of isophorone diisocyanate. These may be used alone or in combination of two or more.

One method for producing isocyanate trimers is to partially trimerize the isocyanate groups of the polyisocyanates using an appropriate trimerization catalyst, such as tertiary amines, phosphines, alkoxides, metal oxides, or carboxylates. The trimerization is then stopped by adding a catalyst poison, and the unreacted polyisocyanate is then removed by solvent extraction and thin-film distillation to obtain the desired isocyanurate group-containing polyisocyanate.

Examples of compounds with a number average molecular weight of 300 to 10,000 that have one or two hydroxyl groups in the same molecule include polyether glycols, polyester glycols, polycarbonate glycols, polyolefin glycols, etc., as well as compounds in which one terminal hydroxyl group of these compounds is alkoxylated with an alkyl group having 1 to 25 carbon atoms, and mixtures of two or more of these.

Examples of polyether glycols include polyether diols, polyether ester diols, and mixtures of two or more of these. Examples of polyether diols include those obtained by homopolymerizing or copolymerizing alkylene oxides, such as polyethylene glycol, polypropylene glycol, polyethylene-propylene glycol, polyoxytetramethylene glycol, polyoxyhexamethylene glycol, polyoxyoctamethylene glycol, and mixtures of two or more of these.

Polyetherester diols include those obtained by reacting an ether group-containing diol or a mixture with another glycol with a dicarboxylic acid or its anhydride, or by reacting a polyester glycol with an alkylene oxide, such as poly(polyoxytetramethylene) adipate. The most preferred polyether glycols are polyethylene glycol, polypropylene glycol, polyoxytetramethylene glycol, or compounds in which one terminal hydroxyl group of these compounds is alkoxylated with an alkyl group having 1 to 25 carbon atoms.

Examples of polyester glycols include dicarboxylic acids (succinic acid, glutaric acid, adipic acid, sebacic acid, fumaric acid, maleic acid, phthalic acid, etc.) or their anhydrides and glycols (ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 2-methyl-1,3-propanediol, 2-methyl-2-propyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,5-pentanediol, 1,6-hexanediol, 2-methyl-2,4-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-1,3-hexanediol, 2-ethyl-2,4-pentane ... Examples of polyester glycols include those obtained by polycondensation of a diol with an N-alkyldiol (e.g., aliphatic glycols such as hexanediol, 2,5-dimethyl-2,5-hexanediol, 1,8-octamethylene glycol, 2-methyl-1,8-octamethylene glycol, 1,9-nonanediol, alicyclic glycols such as bishydroxymethylcyclohexane, aromatic glycols such as xylylene glycol and bishydroxyethoxybenzene, and N-alkyldialkanolamines such as N-methyldiethanolamine), such as polyethylene adipate, polybutylene adipate, polyhexamethylene adipate, and polyethylene/propylene adipate; and polylactone diols or polylactone monools obtained using the above diols or monohydric alcohols having 1 to 25 carbon atoms as initiators, such as polycaprolactone glycol and polymethylvalerolactone, and mixtures of two or more thereof. The most preferred polyester glycols are polycaprolactone glycol or polycaprolactone initiated with an alcohol having 1 to 25 carbon atoms.

Examples of polycarbonate glycols include poly(1,6-hexylene) carbonate and poly(3-methyl-1,5-pentylene) carbonate, and examples of polyolefin glycols include polybutadiene glycol, hydrogenated polybutadiene glycol, and hydrogenated polyisoprene glycol.
These may be used alone or in combination of two or more.

The number average molecular weight of the compound having one or two hydroxyl groups in the same molecule is usually 300 to 10,000, preferably 500 to 6,000, and more preferably 1,000 to 4,000.
Next, a compound having an active hydrogen and a tertiary amino group in the same molecule will be described. The active hydrogen, i.e., the hydrogen atom directly bonded to an oxygen atom, nitrogen atom, or sulfur atom, includes a hydrogen atom in a functional group such as a hydroxyl group, an amino group, or a thiol group, and among these, a hydrogen atom in an amino group, particularly a primary amino group, is preferred.

The tertiary amino group is not particularly limited, but examples thereof include an amino group having an alkyl group having 1 to 4 carbon atoms, or a heterocyclic structure, more specifically an imidazole ring or a triazole ring.
Examples of such compounds having an active hydrogen and a tertiary amino group in the same molecule include N,N-dimethyl-1,3-propanediamine, N,N-diethyl-1,3-propanediamine, N,N-dipropyl-1,3-propanediamine, N,N-dibutyl-1,3-propanediamine, N,N-dimethylethylenediamine, N,N-diethylethylenediamine, N,N-dipropylethylenediamine, N,N-dibutylethylenediamine, N,N-dimethyl-1,4-butanediamine, N,N-diethyl-1,4-butanediamine, N,N-dipropyl-1,4-butanediamine, and N,N-dibutyl-1,4-butanediamine.

When the tertiary amino group has a nitrogen-containing heterocyclic structure, examples of the nitrogen-containing heterocyclic ring include five-membered N-containing heterocyclic rings such as a pyrazole ring, imidazole ring, triazole ring, tetrazole ring, indole ring, carbazole ring, indazole ring, benzimidazole ring, benzotriazole ring, benzoxazole ring, benzothiazole ring, and benzothiadiazole ring, and six-membered nitrogen-containing heterocyclic rings such as a pyridine ring, pyridazine ring, pyrimidine ring, triazine ring, quinoline ring, acridine ring, and isoquinoline ring. Of these nitrogen-containing heterocyclic rings, an imidazole ring or a triazole ring is preferred.

Specific examples of compounds having an imidazole ring and an amino group include 1-(3-aminopropyl)imidazole, histidine, 2-aminoimidazole, and 1-(2-aminoethyl)imidazole. Specific examples of compounds having a triazole ring and an amino group include 3-amino-1,2,4-triazole, 5-(2-amino-5-chlorophenyl)-3-phenyl-1H-1,2,4-triazole, 4-amino-4H-1,2,4-triazole-3,5-diol, 3-amino-5-phenyl-1H-1,3,4-triazole, 5-amino-1,4-diphenyl-1,2,3-triazole, and 3-amino-1-benzyl-1H-2,4-triazole. Of these, N,N-dimethyl-1,3-propanediamine, N,N-diethyl-1,3-propanediamine, 1-(3-aminopropyl)imidazole, and 3-amino-1,2,4-triazole are preferred.

These may be used alone or in combination of two or more.
The preferred blending ratio of raw materials when producing a urethane-based polymer dispersant is 10 to 200 parts by mass, preferably 20 to 190 parts by mass, and more preferably 30 to 180 parts by mass of a compound having one or two hydroxyl groups in the same molecule and a number average molecular weight of 300 to 10,000, and 0.2 to 25 parts by mass, preferably 0.3 to 24 parts by mass of a compound having an active hydrogen and a tertiary amino group in the same molecule, relative to 100 parts by mass of a polyisocyanate compound.

Urethane-based polymer dispersants are manufactured using known methods for manufacturing polyurethane resins. Examples of solvents used in manufacturing include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, and isophorone; esters such as ethyl acetate, butyl acetate, and cellosolve acetate; hydrocarbons such as benzene, toluene, xylene, and hexane; alcohols such as diacetone alcohol, isopropanol, sec-butanol, and tert-butanol; chlorides such as methylene chloride and chloroform; ethers such as tetrahydrofuran and diethyl ether; and aprotic polar solvents such as dimethylformamide, N-methylpyrrolidone, and dimethyl sulfoxide. These solvents may be used alone or in combination.

In the above production, a urethane reaction catalyst is typically used. Examples of this catalyst include one or more of the following: tin-based catalysts such as dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin dioctoate, and stannous octoate; iron-based catalysts such as iron acetylacetonate and ferric chloride; and tertiary amine-based catalysts such as triethylamine and triethylenediamine.

<Method for measuring amine value>
The tertiary amine value of a dispersant is expressed as the mass of KOH equivalent to the amount of base per gram of solids excluding the solvent in a dispersant sample, and can be measured by the following method.
Accurately weigh out 0.5 to 1.5 g of dispersant sample into a 100 mL beaker and dissolve in 50 mL of acetic acid. Using an automatic titrator equipped with a pH electrode, neutralize this solution with a 0.1 mol/L HClO ₄ (perchloric acid) acetic acid solution. The inflection point on the titration pH curve is used as the titration endpoint, and the amine value is calculated using the following formula.

Amine value [mg KOH/g] = (561 × V) / (W × S)
(W represents the weight of the dispersant sample [g], V represents the titration amount at the end of the titration [mL], and S represents the solids concentration of the dispersant sample [% by mass].)
The amount of the compound having an active hydrogen and a tertiary amino group introduced in the same molecule is preferably controlled to a range of 1 to 100 mg KOH/g in terms of amine value after reaction. A range of 5 to 95 mg KOH/g is more preferred. The amine value is a value obtained by neutralizing a basic amino group with an acid and expressing it in mg of KOH corresponding to the acid value. By setting the amine value at or above the lower limit, dispersibility tends to be improved. By setting the amine value at or below the upper limit, developability tends to be improved.

If isocyanate groups remain in the polymer dispersant after the above reaction, it is preferable to further consume the isocyanate groups with an alcohol or an amino compound, as this increases the stability of the product over time.
The weight-average molecular weight (Mw) of the urethane polymer dispersant is typically in the range of 1,000 to 200,000, preferably 2,000 to 100,000, and more preferably 3,000 to 50,000. It is particularly preferably 30,000 or less. By setting the Mw at or above the lower limit, dispersibility and dispersion stability tend to be improved. Furthermore, by setting the Mw at or below the upper limit, solubility tends to be improved. The above upper and lower limits can be arbitrarily combined. For example, the Mw may be 1,000 to 30,000, 2,000 to 30,000, or 3,000 to 30,000. A molecular weight of 30,000 or less tends to improve alkaline developability, especially when the pigment concentration is high. Examples of such particularly preferred commercially available urethane dispersants include Disperbyk 167 and 182 (BYK-Chemie).

When the photosensitive resin composition of the present invention contains a dispersant, the content of the dispersant is usually 50% by mass or less, preferably 30% by mass or less, more preferably 20% by mass or less, and usually 1% by mass or more, preferably 3% by mass or more, more preferably 5% by mass or more, even more preferably 7% by mass or more, and particularly preferably 10% by mass or more, based on the total solid content of the photosensitive resin composition. The above upper and lower limits can be arbitrarily combined. For example, the content is preferably 1 to 50% by mass, more preferably 3 to 50% by mass, even more preferably 5 to 30% by mass, even more preferably 7 to 30% by mass, and particularly preferably 10 to 20% by mass.
The content of the dispersant is usually 5 parts by mass or more, preferably 10 parts by mass or more, and more preferably 15 parts by mass or more, relative to 100 parts by mass of the (D) colorant, and usually 200 parts by mass or less, preferably 80 parts by mass or less, and more preferably 50 parts by mass or less. The above upper and lower limits can be arbitrarily combined. For example, 5 to 200 parts by mass is preferred, 10 to 80 parts by mass is more preferred, and 15 to 50 parts by mass is even more preferred.
By adjusting the content to be equal to or greater than the lower limit, sufficient dispersibility tends to be ensured, while by adjusting the content to be equal to or less than the upper limit, sufficient color density, sensitivity, film-forming properties, etc. tend to be achieved without reducing the proportions of other components.

<Thiols>
The photosensitive resin composition of the present invention preferably contains a thiol in order to improve sensitivity and adhesion to a substrate. Examples of thiols include hexanedithiol, decanedithiol, 1,4-dimethylmercaptobenzene, butanediol bisthiopropionate, butanediol bisthioglycolate, ethylene glycol bisthioglycolate, trimethylolpropane tristhioglycolate, butanediol bisthiopropionate, trimethylolpropane tristhiopropionate, trimethylolpropane tristhioglycolate, pentaerythritol tetrakisthiopropionate, pentaerythritol tetrakisthioglycolate, trishydroxyethyl tristhiopropionate, ethylene glycol bis(3-mercaptobutyrate), propylene glycol bis(3-mercaptobutyrate) (PGMB), butanediol bis(3-mercaptobutyrate), 1,4-bis(3-mercaptobutyryloxy)butane; (trade name: Karenz MT) BD1, manufactured by Showa Denko K.K.), butanediol trimethylolpropane tris(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptobutyrate); (trade name: Karenz MT PE1, manufactured by Showa Denko K.K.), pentaerythritol tris(3-mercaptobutyrate), ethylene glycol bis(3-mercaptoisobutyrate), butanediol bis(3-mercaptoisobutyrate), trimethylolpropane tris(3-mercaptoisobutyrate), trimethylolpropane tris(3-mercaptobutyrate) (TPMB), trimethylolpropane tris(2-mercaptoisobutyrate) (TPMIB), 1,3,5-tris(3-mercaptobutyloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (trade name: Karenz MT NR1, manufactured by Showa Denko K.K. Various types of these can be used alone or in combination of two or more.
Polyfunctional thiols such as PGMB, TPMB, TPMIB, Karenz MT BD1, Karenz MT PE1, and Karenz MT NR1 are preferred, and among these, Karenz MT BD1, Karenz MT PE1, and Karenz MT NR1 are more preferred, and Karenz MT PE1 is particularly preferred.

When a thiol compound is used, the content of the thiol compound is preferably 0.1 mass% or more, more preferably 0.3 mass% or more, and even more preferably 0.5 mass% or more, relative to the total solid content of the photosensitive resin composition of the present invention, and is usually 10 mass% or less, preferably 5 mass% or less. By making the content equal to or greater than the lower limit, sensitivity deterioration tends to be suppressed. Furthermore, by making the content equal to or less than the upper limit, storage stability tends to be improved.
The upper and lower limits can be combined in any manner. For example, the content is preferably 0.1 to 10% by mass, more preferably 0.3 to 10% by mass, and even more preferably 0.5 to 5% by mass.

<Solvent>
The photosensitive resin composition of the present invention is generally used in a state in which various materials including (A) an alkali-soluble resin, (B) a photopolymerizable monomer, (C) a photopolymerization initiator, and (D) a colorant, which is used as needed, are dissolved or dispersed in an organic solvent.
As the solvent, the organic solvent used in the production method of the present invention or the organic solvent contained in the carboxy group-containing resin-containing liquid of the present invention may be used as it is.
The organic solvent to be selected preferably has a boiling point (under a pressure of 1013.25 [hPa]; the same applies hereinafter to all boiling points) in the range of 100 to 300°C. A solvent having a boiling point of 120 to 280°C is more preferred.
Examples of such organic solvents include the following:

Glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-butyl ether, propylene glycol t-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, methoxymethyl pentanol, dipropylene glycol monoethyl ether, dipropylene glycol monomethyl ether, 3-methyl-3-methoxybutanol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, and tripropylene glycol methyl ether;

glycol dialkyl ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, and dipropylene glycol dimethyl ether;
glycol alkyl ether acetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-butyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, methoxybutyl acetate, 3-methoxybutyl acetate, methoxypentyl acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-butyl ether acetate, dipropylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether acetate, triethylene glycol monoethyl ether acetate, and 3-methyl-3-methoxybutyl acetate;

glycol diacetates such as ethylene glycol diacetate, 1,3-butylene glycol diacetate, and 1,6-hexanol diacetate;
alkyl acetates such as cyclohexanol acetate;
ethers such as amyl ether, diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, diamyl ether, ethyl isobutyl ether, and dihexyl ether;
ketones such as acetone, methyl ethyl ketone, methyl amyl ketone, methyl isopropyl ketone, methyl isoamyl ketone, diisopropyl ketone, diisobutyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl amyl ketone, methyl butyl ketone, methyl hexyl ketone, methyl nonyl ketone, and methoxymethyl pentanone;
monohydric or polyhydric alcohols such as ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol, propylene glycol, butanediol, diethylene glycol, dipropylene glycol, triethylene glycol, methoxymethylpentanol, glycerin, and benzyl alcohol;
aliphatic hydrocarbons such as n-pentane, n-octane, diisobutylene, n-hexane, hexene, isoprene, dipentene, and dodecane;
Alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, methylcyclohexene, and bicyclohexyl;

Aromatic hydrocarbons such as benzene, toluene, xylene, and cumene;
Chain or cyclic esters such as amyl formate, ethyl formate, ethyl acetate, butyl acetate, propyl acetate, amyl acetate, methyl isobutyrate, ethylene glycol acetate, ethyl propionate, propyl propionate, butyl butyrate, isobutyl butyrate, methyl isobutyrate, ethyl caprylate, butyl stearate, ethyl benzoate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, and γ-butyrolactone;
Alkoxycarboxylic acids such as 3-methoxypropionic acid and 3-ethoxypropionic acid;

Halogenated hydrocarbons such as butyl chloride and amyl chloride;
ether ketones such as methoxymethylpentanone;
nitriles such as acetonitrile and benzonitrile;
Examples of commercially available solvents that fall under the above category include mineral spirits, Balsol #2, Apco #18 Solvent, Apco Thinner, Socal Solvent No. 1 and No. 2, Solvesso #150, Shell TS28 Solvent, Carbitol, ethyl carbitol, butyl carbitol, methyl cellosolve ("Cellosolve" is a registered trademark, the same applies hereinafter), ethyl cellosolve, ethyl cellosolve acetate, methyl cellosolve acetate, and diglyme (all of which are trade names).

These organic solvents may be used alone or in combination of two or more kinds.
When forming pixels or black matrices of a color filter by photolithography, it is preferable to select an organic solvent having a boiling point in the range of 100 to 250°C, more preferably 120 to 230°C.
Of the above organic solvents, glycol alkyl ether acetates are preferred because they have a good balance of application properties, surface tension, etc., and the solubility of the components in the composition is relatively high.

Glycol alkyl ether acetates may be used alone or in combination with other organic solvents. Glycol monoalkyl ethers are particularly preferred as other organic solvents that may be used in combination. Among these, propylene glycol monomethyl ether is particularly preferred due to its ability to dissolve the components in the composition. Glycol monoalkyl ethers are highly polar, and adding too much tends to cause the colorant to aggregate, increasing the viscosity of the resulting photosensitive resin composition and reducing storage stability. Therefore, the proportion of glycol monoalkyl ethers in the solvent is preferably 5% to 30% by weight, and more preferably 5% to 20% by weight.

It is also preferable to use an organic solvent with a boiling point of 200°C or higher (hereinafter sometimes referred to as a "high-boiling solvent"). The use of such a high-boiling solvent makes the photosensitive resin composition less likely to dry, but also prevents the uniform dispersion of the colorant in the composition from being destroyed by rapid drying. This effectively prevents the occurrence of foreign matter defects caused by precipitation and solidification of the colorant, for example, at the tip of the slit nozzle. Among the various solvents mentioned above, dipropylene glycol methyl ether acetate, diethylene glycol mono-n-butyl ether acetate, diethylene glycol monoethyl ether acetate, 1,4-butanediol diacetate, 1,3-butylene glycol diacetate, triacetin, and 1,6-hexanediol diacetate are particularly preferred due to their effectiveness.

The content of the high-boiling point solvent in the organic solvent is preferably 0% to 50% by mass, more preferably 0.5% to 40% by mass, and particularly preferably 1% to 30% by mass. By ensuring that the content is above the lower limit, it tends to be possible to prevent, for example, the coloring material from precipitating and solidifying at the tip of the slit nozzle, which could cause foreign matter defects. Furthermore, by ensuring that the content is below the upper limit, it tends to be possible to slow down the drying temperature of the composition, which tends to be possible to prevent problems in the color filter manufacturing process, such as poor tact time in the reduced-pressure drying process and pin marks during pre-baking.

In the photosensitive resin composition of the present invention, the content of the organic solvent is not particularly limited. However, from the viewpoint of ease of application and viscosity stability, the total solids content in the photosensitive resin composition is preferably 5% by mass or more, more preferably 8% by mass or more, even more preferably 10% by mass or more, and preferably 40% by mass or less, more preferably 30% by mass or less, even more preferably 25% by mass or less, and particularly preferably 20% by mass or less.

<Other ingredients of photosensitive resin composition>
In addition to the above-mentioned components, the photosensitive resin composition of the present invention may contain, as appropriate, adhesion improvers, coating property improvers, pigment derivatives, development improvers, ultraviolet absorbers, antioxidants, and the like.

<Adhesion improver>
To improve adhesion to the substrate, an adhesion promoter may be added, for example, a silane coupling agent or a titanium coupling agent, with the silane coupling agent being particularly preferred.
Examples of such silane coupling agents include KBM-402, KBM-403, KBM-502, KBM-5103, KBE-9007, X-12-1048, and X-12-1050 (manufactured by Shin-Etsu Silicones Co., Ltd.), and Z-6040, Z-6043, and Z-6062 (manufactured by Dow Corning Toray Co., Ltd.). The silane coupling agents may be used alone or in any combination and ratio of two or more.
Furthermore, an adhesion improver other than the silane coupling agent may be contained in the photosensitive resin composition of the present invention, and examples thereof include phosphoric acid-based adhesion improvers and other adhesion improvers.

As phosphoric acid-based adhesion promoters, (meth)acryloyloxy group-containing phosphates are preferred, and among them, those represented by the following general formulas (g1), (g2), and (g3) are preferred.

In the above general formulae (g1), (g2) and (g3), R51 each independently represents a hydrogen atom or a methyl group, l and l' each independently represents an integer of 1 to 10, and m each independently represents 1, 2 or 3.
Other examples of adhesion improvers include TEGO*Add Bond LTH (manufactured by Evonik), etc. These phosphate group-containing compounds and other adhesion improvers may be used alone or in combination of two or more.

When the photosensitive resin composition of the present invention contains an adhesion improver, the content of the adhesion improver in the photosensitive resin composition is not particularly limited, but is preferably 0.01 mass% or more, more preferably 0.1 mass% or more, and even more preferably 0.5 mass% or more, and is preferably 5 mass% or less, more preferably 3 mass% or less, even more preferably 2 mass% or less, and particularly preferably 1.5 mass% or less, based on the total solid content of the photosensitive resin composition. By making the content equal to or greater than the lower limit, adhesion tends to be improved. On the other hand, by making the content equal to or less than the upper limit, developability tends to be improved.
The upper and lower limits can be combined in any manner. For example, the content is preferably 0.01 to 5% by mass, more preferably 0.01 to 3% by mass, even more preferably 0.1 to 2% by mass, and particularly preferably 0.5 to 1.5% by mass.

<Coatability improver>
The photosensitive resin composition of the present invention may contain a surfactant as a coatability improver to improve coatability. Examples of surfactants that can be used include anionic, cationic, nonionic, and amphoteric surfactants. Among these, nonionic surfactants are preferred because they are less likely to adversely affect various properties, and fluorine-based or silicone-based surfactants are particularly effective in terms of coatability.

Examples of such surfactants include TSF4460 (manufactured by Momentive Performance Materials), DFX-18 (manufactured by Neos Corporation), BYK-300, BYK-325, BYK-330 (manufactured by BYK-Chemie), KP340 (manufactured by Shin-Etsu Silicones Co., Ltd.), F-470, F-475, F-478, F-554, F-559 (manufactured by DIC Corporation), SH7PA (manufactured by Dow Corning Toray Co., Ltd.), DS-401 (manufactured by Daikin Corporation), L-77 (manufactured by Nippon Unicar Co., Ltd.), and FC4430 (manufactured by 3M Japan Co., Ltd.). The surfactants may be used alone or in any combination and ratio of two or more.
When the photosensitive resin composition of the present invention contains a surfactant, the content of the surfactant in the photosensitive resin composition is not particularly limited, but is preferably 0.01 mass% or more, more preferably 0.05 mass% or more, and is preferably 1.0 mass% or less, more preferably 0.7 mass% or less, even more preferably 0.5 mass% or less, and particularly preferably 0.3 mass% or less, based on the total solid content of the photosensitive resin composition. By setting the content at or above the lower limit, the resist coating uniformity tends to improve. Furthermore, by setting the content at or below the upper limit, the resist sensitivity tends not to decrease.
The upper and lower limits can be combined in any manner. For example, the content is preferably 0.01 to 1.0 mass%, more preferably 0.01 to 0.7 mass%, even more preferably 0.05 to 0.5 mass%, and particularly preferably 0.05 to 0.3 mass%.

<Pigment derivatives>
The photosensitive resin composition of the present invention may contain a pigment derivative to improve dispersibility and storage stability. Examples of the pigment derivative include azo-based, phthalocyanine-based, quinacridone-based, benzimidazolone-based, quinophthalone-based, isoindolinone-based, dioxazine-based, anthraquinone-based, indanthrene-based, perylene-based, perinone-based, diketopyrrolopyrrole-based, and dioxazine-based derivatives, with phthalocyanine-based and quinophthalone-based derivatives being preferred.

Substituents of pigment derivatives include sulfonic acid groups, sulfonamide groups and their quaternary salts, phthalimidomethyl groups, dialkylaminoalkyl groups, hydroxyl groups, carboxy groups, and amide groups, which are bonded to the pigment skeleton directly or via alkyl groups, aryl groups, heterocyclic groups, etc., with sulfonic acid groups being preferred. Multiple of these substituents may also be substituted on a single pigment skeleton. Specific examples of pigment derivatives include sulfonic acid derivatives of phthalocyanine, sulfonic acid derivatives of quinophthalone, sulfonic acid derivatives of anthraquinone, sulfonic acid derivatives of quinacridone, sulfonic acid derivatives of diketopyrrolopyrrole, and sulfonic acid derivatives of dioxazine. These may be used alone or in combination of two or more.

When the photosensitive resin composition of the present invention contains a pigment derivative, the blending ratio of the pigment derivative is not particularly limited, but is preferably 0.1 mass % or more, more preferably 0.5 mass % or more, and even more preferably 1.0 mass % or more, based on the total solid content of the photosensitive resin composition. By making the blending ratio equal to or greater than the lower limit, dispersion stability tends to be improved. By making the blending ratio equal to or less than the upper limit, developability tends to be improved.
The upper and lower limits can be combined in any manner. For example, the content is preferably 0.1 to 10% by mass, more preferably 0.5 to 10% by mass, and even more preferably 1.0 to 5% by mass.

<Physical Properties of Photosensitive Resin Composition>
The photosensitive resin composition of the present invention can be suitably used for forming a black matrix, and from this viewpoint, it preferably exhibits a black color. Furthermore, the optical density (OD) per μm of film thickness of the coating film is preferably 1.0 or more, more preferably 2.0 or more, even more preferably 2.5 or more, even more preferably 3.0 or more, particularly preferably 4.0 or more, most preferably 4.5 or more, and is usually 6.0 or less; for example, 1.0 to 6.0 is preferred, 2.0 to 6.0 is more preferred, 2.5 to 6.0 is more preferred, 3.0 to 6.0 is even more preferred, 4.0 to 6.0 is particularly preferred, and 4.5 to 6.0 is most preferred. By ensuring that the OD is equal to or greater than the lower limit, sufficient light-blocking properties tend to be ensured.

<Method for producing photosensitive resin composition>
When the photosensitive resin composition of the present invention contains a (D) colorant, the (D) colorant is preferably subjected to a dispersion treatment in advance using a paint conditioner, sand grinder, ball mill, roll mill, stone mill, jet mill, homogenizer, or the like. The dispersion treatment results in the (D) colorant being microparticulated, thereby improving the coating properties of the resist. Furthermore, when a black colorant is used as the (D) colorant, this contributes to improving the light-shielding ability.

The dispersion treatment is preferably carried out in a system that combines (D) a colorant, an organic solvent, and, if necessary, a dispersant, and part or all of (A) an alkali-soluble resin. (Hereinafter, the mixture to be subjected to the dispersion treatment and the composition obtained by the dispersion treatment may be referred to as an "ink" or a "pigment dispersion.") In particular, using a polymer dispersant as the dispersant is preferred because it inhibits the resulting ink and resist from thickening over time (leading to excellent dispersion stability).
When a dispersion treatment is performed on a liquid containing all the components to be blended into the photosensitive resin composition, the heat generated during the dispersion treatment may cause denaturation of highly reactive components. Therefore, it is preferable to perform the dispersion treatment in a system containing a polymer dispersant.

When dispersing (D) colorant using a sand grinder, glass beads or zirconia beads with a diameter of approximately 0.1 to 8 mm are preferably used. Dispersion conditions typically involve a temperature between 0°C and 100°C, preferably between room temperature and 80°C. The optimum dispersion time varies depending on the liquid composition and the size of the dispersion treatment device, so adjust accordingly. The standard for dispersion is to control the gloss of the ink so that the resist's 20-degree specular gloss (JIS Z8741) is in the range of 100 to 200. If the resist has low gloss, the dispersion treatment is often insufficient, leaving coarse pigment (colorant) particles, which can result in insufficient developability, adhesion, resolution, and other properties. Furthermore, if the dispersion treatment is performed until the gloss value exceeds the above range, the pigment will break down, producing numerous ultrafine particles, which can actually impair dispersion stability.

Next, the components contained in the photosensitive resin composition, namely (A) alkali-soluble resin, (B) photopolymerizable monomer, (C) photopolymerization initiator, and (D) colorant, if present, are blended with the ink obtained by the above dispersion process and mixed at a temperature of 20-30°C to form a uniform solution. Since fine dust particles often become mixed into the liquid during the manufacturing process of the photosensitive resin composition, it is desirable to filter the resulting resist using a filter or the like.

[ink]
The ink production method of the present invention is a method for producing an ink containing (A) an alkali-soluble resin, an organic solvent, and (D) a colorant, and includes blending a carboxy group-containing resin produced by the production method of the present invention as the alkali-soluble resin (A).The ink may also contain a dispersant, if necessary.
As the organic solvent, (D) coloring material, and dispersant, those used in the photosensitive resin composition can be preferably used.

<Ink manufacturing method>
The ink of the present invention can be obtained, for example, by the dispersion treatment described in the method for producing the photosensitive resin composition.

[Cured product]
The method for producing a cured product of the present invention includes curing the photosensitive resin composition obtained by the production method of the present invention.
A cured product obtained by curing the photosensitive resin composition can be suitably used as a component for a color filter, such as a pixel, a black matrix, or a colored spacer.

[Black matrix]
The method for producing a black matrix of the present invention includes forming a black matrix using the cured product obtained by the production method of the present invention.
A black matrix using the cured product obtained by the production method of the present invention will be described in accordance with the production method.

(1) Support The material of the support for forming the black matrix is not particularly limited as long as it has adequate strength. Transparent substrates are mainly used, and examples of the material include polyester resins such as polyethylene terephthalate, polyolefin resins such as polypropylene and polyethylene, thermoplastic resin sheets such as polycarbonate, polymethyl methacrylate, and polysulfone, thermosetting resin sheets such as epoxy resins, unsaturated polyester resins, and poly(meth)acrylic resins, and various types of glass. Among these, glass and heat-resistant resins are preferred from the viewpoint of heat resistance. Furthermore, a transparent electrode such as ITO or IZO may be formed on the surface of the substrate. It is also possible to form the black matrix on a substrate other than a transparent substrate, for example, a TFT array.

In order to improve surface properties such as adhesiveness, the support may be subjected to corona discharge treatment, ozone treatment, atmospheric pressure plasma treatment, or thin film formation treatment using a silane coupling agent or various resins such as urethane resins, as necessary.
The thickness of the transparent substrate is usually in the range of 0.05 to 10 mm, preferably 0.1 to 7 mm. When a thin film of various resins is formed, the thickness is usually in the range of 0.01 to 10 μm, preferably 0.05 to 5 μm.

(2) Black Matrix As a method for forming a black matrix using the cured product obtained by the production method of the present invention, there is a method for forming a black matrix using the cured product obtained by curing the photosensitive resin composition obtained by the production method of the present invention. For example, there is a method for forming a black matrix by applying the photosensitive resin composition of the present invention to a transparent substrate and drying it, placing a photomask on the dried sample, and performing image exposure through the photomask, developing, and, if necessary, thermal curing or photocuring.

(3) Formation of Black Matrix (3-1) Coating of Photosensitive Resin Composition Coating of the photosensitive resin composition for a black matrix onto a transparent substrate can be carried out by a spinner method, a wire bar method, a flow coating method, a die coating method, a roll coating method, a spray coating method, etc. Among these, the die coating method is preferred from an overall viewpoint, since it significantly reduces the amount of coating liquid used, is completely free from the influence of mist or the like that adheres when using spin coating, and suppresses the generation of foreign matter.

The thickness of the coating film, after drying, is usually preferably in the range of 0.2 to 10 μm, more preferably 0.5 to 6 μm, and even more preferably 1 to 4 μm. Setting it below the upper limit tends to facilitate pattern development and gap adjustment during the liquid crystal cell fabrication process. Setting it above the lower limit tends to facilitate the desired color expression.

(3-2) Drying of Coating Film After applying the photosensitive resin composition to the substrate, the coating film is preferably dried using a drying method using a hot plate, an IR oven, or a convection oven. Drying conditions can be appropriately selected depending on the type of solvent component, the performance of the dryer used, etc. The drying time is usually selected in the range of 15 seconds to 5 minutes at a temperature of 40 to 200°C, and preferably in the range of 30 seconds to 3 minutes at a temperature of 50 to 130°C, depending on the type of solvent component, the performance of the dryer used, etc.

The higher the drying temperature, the better the adhesion of the coating to the transparent substrate; however, if the temperature is too high, the alkali-soluble resin may decompose, inducing thermal polymerization and resulting in poor development. The coating drying process may also be performed under reduced pressure in a vacuum chamber without increasing the temperature.

(3-3) Exposure Imagewise exposure is carried out by superimposing a negative mask pattern on the coating film of the photosensitive resin composition and irradiating the coating film with light having a wavelength ranging from the ultraviolet region to the visible region through this mask pattern. If necessary, an oxygen-blocking layer such as a polyvinyl alcohol layer may be formed on the photopolymerizable coating film before exposure in order to prevent a decrease in the sensitivity of the photopolymerizable layer due to oxygen. The light source used for the imagewise exposure is not particularly limited. Examples of light sources include lamp light sources such as xenon lamps, halogen lamps, tungsten lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, medium-pressure mercury lamps, low-pressure mercury lamps, and carbon arc lamps. When using light of a specific wavelength, an optical filter can also be used.

(3-4) Development The black matrix of the present invention can be prepared by imagewise exposing a coating film of the photosensitive resin composition to the above-mentioned light source, followed by development using an organic solvent or an aqueous solution containing a surfactant and an alkaline compound to form an image on a substrate. This aqueous solution may further contain an organic solvent, a buffer, a complexing agent, a dye, or a pigment.

Examples of alkaline compounds include inorganic alkaline compounds such as sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, sodium silicate, potassium silicate, sodium metasilicate, sodium phosphate, potassium phosphate, sodium hydrogen phosphate, potassium hydrogen phosphate, sodium dihydrogen phosphate, potassium dihydrogen phosphate, and ammonium hydroxide; and organic alkaline compounds such as mono-, di-, or triethanolamine, mono-, di-, or trimethylamine, mono-, di-, or triethylamine, mono- or diisopropylamine, n-butylamine, mono-, di-, or triisopropanolamine, ethyleneimine, ethylenediimine, tetramethylammonium hydroxide (TMAH), and choline. These alkaline compounds may be used alone or in combination.

Examples of surfactants include nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl aryl ethers, polyoxyethylene alkyl esters, sorbitan alkyl esters, and monoglyceride alkyl esters; anionic surfactants such as alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl sulfates, alkyl sulfonates, and sulfosuccinate ester salts; and amphoteric surfactants such as alkyl betaines and amino acids.

Examples of the organic solvent include isopropyl alcohol, benzyl alcohol, ethyl cellosolve, butyl cellosolve, phenyl cellosolve, propylene glycol, and diacetone alcohol. The organic solvent may be used alone or in combination with an aqueous solution.
The conditions for the development treatment are not particularly limited. Usually, the development temperature is in the range of 10 to 50°C, preferably 15 to 45°C, and particularly preferably 20 to 40°C. The development method can be any of immersion development, spray development, brush development, ultrasonic development, and the like.

(3-5) Thermal Curing Treatment After development, the substrate is subjected to a thermal curing treatment or a photocuring treatment, preferably a thermal curing treatment. The thermal curing conditions are selected such that the temperature is in the range of 100 to 280°C, preferably 150 to 250°C, and the time is in the range of 5 to 60 minutes.
The height of the black matrix formed in this manner is usually 0.5 to 5 μm, preferably 0.8 to 4 μm.
Furthermore, the optical density (OD) per 1 μm of thickness is 2.0 or more, preferably 2.5 or more, more preferably 3.0 or more, and particularly preferably 3.2 or more.

[Formation of other color filters]
A photosensitive resin composition containing a colorant of one of red, green, and blue colors is applied to a transparent substrate provided with a black matrix using the same processes as those described above in (3-1) to (3-5), and after drying, a photomask is placed on the coating film. A pixel image is formed by imagewise exposure through the photomask, development, and, if necessary, heat curing or photocuring to produce a colored layer. This operation is performed for each of the photosensitive resin compositions of three colors (red, green, and blue), thereby forming a color filter. The order of these processes is not limited to the above.

[Colored spacer]
The photosensitive resin composition obtained by the production method of the present invention can also be used as a resist for colored spacers in addition to black matrices. When spacers are used in TFT-type LCDs, light incident on the TFTs can cause the TFTs to malfunction as switching elements, and colored spacers are used to prevent this. For example, Japanese Patent Application Laid-Open No. 8-234212 describes making spacers light-blocking. Colored spacers can be formed in the same manner as the black matrix described above, except that a mask for colored spacers is used.

(3-6) Formation of Transparent Electrode A color filter is used as a part of a component of a color display, a liquid crystal display device, etc. by forming a transparent electrode such as ITO on the image in its current state, but in order to improve the surface smoothness and durability, a top coat layer of polyamide, polyimide, etc. can be formed on the image as needed. In some applications such as a planar alignment driving system (IPS mode), a transparent electrode may not be formed.

[Bulkhead]
The photosensitive resin composition obtained by the production method of the present invention or the photosensitive resin composition of the present invention can also be used to form partition walls, particularly partition walls for separating organic layers of organic electroluminescent devices. Examples of organic layers used in organic electroluminescent devices include organic layers used as hole injection layers, hole transport layers, or hole transport layers on hole injection layers, as described in JP 2016-165396 A.

The photosensitive resin composition obtained by the manufacturing method of the present invention or the partition wall using the photosensitive resin composition of the present invention will be described according to the manufacturing method.

(4-1) Support The support and substrate for forming the partition walls may be the same as the support and substrate for forming the black matrix described above.

(4-2) Partition Walls Hereinafter, the case of use as partition walls will be described with reference to specific examples of a method for forming partition walls using the photosensitive resin composition obtained by the production method of the present invention or the photosensitive resin composition of the present invention.

Usually, a photosensitive resin composition is applied in the form of a film or a pattern by coating or other methods onto a substrate on which partition walls are to be formed, and the solvent is dried. Subsequently, a pattern is formed by a method such as photolithography, which involves exposure and development.
Thereafter, if necessary, additional exposure or heat curing treatment is carried out to form the partition walls on the substrate.

(4-3) Formation of Partition Walls In the method for forming partition walls using the photosensitive resin composition obtained by the production method of the present invention or the photosensitive resin composition of the present invention, specific methods for supplying the photosensitive resin composition to a substrate, drying, exposing, developing, additional exposure, and heat curing treatment can be the same as those used in the formation of the black matrix described above.

When used as a partition wall, the size and shape are adjusted appropriately depending on the specifications of the organic electroluminescent device to which it is applied, but the height of partition walls formed from the photosensitive resin composition is usually around 0.5 to 10 μm.

[Organic electroluminescent device]
The organic electroluminescent device of the present invention comprises a cured product, such as a partition wall, obtained by the production method of the present invention.
For example, various organic electroluminescent devices are manufactured using a substrate having a partition wall pattern manufactured by the above-described method. Although the method for forming the organic electroluminescent device is not particularly limited, the organic electroluminescent device is preferably manufactured by forming a partition wall pattern on a substrate by the above-described method, and then forming organic layers such as pixels by a vapor deposition method in which a functional material is sublimated in a vacuum and deposited in the area surrounded by the partition walls on the substrate to form a film, or by a wet process such as a casting method, a spin coating method, or an inkjet printing method.

The types of organic electroluminescent devices include bottom emission types and top emission types.
A bottom-emission type is fabricated, for example, by forming a partition wall on a glass substrate on which a transparent electrode is laminated, and then laminating a hole transport layer, a light-emitting layer, an electron transport layer, and a metal electrode layer in an opening surrounded by the partition wall, whereas a top-emission type is fabricated, for example, by forming a partition wall on a glass substrate on which a metal electrode layer is laminated, and then laminating an electron transport layer, a light-emitting layer, a hole transport layer, and a transparent electrode layer in an opening surrounded by the partition wall.
Examples of the light-emitting layer include organic electroluminescent layers such as those described in Japanese Patent Application Laid-Open No. 2009-146691 and Japanese Patent No. 5734681. Quantum dots such as those described in Japanese Patent No. 5653387 and Japanese Patent No. 5653101 may also be used.

The layer structure is not limited to this; for example, each of the hole transport layer and electron transport layer may have a laminate structure consisting of two or more layers from the perspective of luminous efficiency. The thickness of each layer is not particularly limited, but is typically 1 to 500 nm from the perspective of luminous efficiency and brightness.

Organic electroluminescent devices may be formed with each RGB color separated by an opening, or two or more colors may be stacked in one opening. Organic electroluminescent devices may also have a sealing layer to improve reliability. The sealing layer prevents moisture in the air from adsorbing to the organic electroluminescent device and reducing luminous efficiency. Organic electroluminescent devices may also have a low-reflection film at the interface with air to improve light extraction efficiency. By placing a low-reflection film at the interface between the air and the device, the refractive index gap can be reduced, and reflection at the interface can be suppressed. For example, moth-eye structure and ultra-multilayer film technologies can be applied to such low-reflection films.

When an organic electroluminescent element is used as a pixel of an image display device, it is necessary to prevent light from the light-emitting layer of a pixel from leaking to other pixels. Furthermore, when electrodes or the like are made of metal, it is necessary to prevent deterioration in image quality due to reflection of external light. Therefore, it is preferable to impart light-shielding properties to the partition walls constituting the organic electroluminescent element.
In an organic electroluminescent device, since it is necessary to provide electrodes on the upper and lower surfaces of the partition walls, the partition walls preferably have high resistance and low dielectric constant from the viewpoint of insulating properties. Therefore, when a colorant is used to provide the partition walls with light-shielding properties, it is preferable to use the above-mentioned organic pigment having high resistance and low dielectric constant.

[Image display device]
The method for producing an image display device of the present invention is characterized by using a cured product obtained by the production method of the present invention or a black matrix obtained by the production method of the present invention.
The image display device of the present invention includes a cured product obtained by the production method of the present invention or a black matrix obtained by the production method of the present invention. The image display device of the present invention has a cured product obtained by curing the photosensitive resin composition of the present invention, and examples of the production method include a production method using the photosensitive resin composition obtained by the production method of the present invention or a cured product, black matrix, or partition wall formed from the photosensitive resin composition of the present invention.
The image display device in the present invention is not particularly limited as long as it is a device that displays images or videos, and examples thereof include a liquid crystal display device and an organic EL display, which will be described later.

[Liquid crystal display device]
The liquid crystal display device of the present invention has the black matrix of the present invention, and is not particularly limited in the order or position of forming the color pixels and the black matrix.

Liquid crystal display devices are typically manufactured by forming an alignment film on a color filter, dispersing spacers on this alignment film, and then bonding it to an opposing substrate to form a liquid crystal cell. Liquid crystal is then injected into the formed liquid crystal cell, and the cell is completed by connecting it to the opposing electrode. A resin film such as polyimide is suitable as the alignment film. Gravure printing and/or flexographic printing are typically used to form the alignment film, and the thickness of the alignment film is several tens of nanometers. After hardening the alignment film by thermal baking, the surface is treated with ultraviolet light or a rubbing cloth to create a surface that allows the tilt of the liquid crystal to be adjusted.

The size of the spacer used depends on the gap (gap) between the opposing substrate, with a size of 2 to 8 μm being typically suitable. A transparent resin film photospacer (PS) can be formed on the color filter substrate using photolithography and used in place of the spacer. An array substrate is typically used as the opposing substrate, with a TFT (thin film transistor) substrate being particularly suitable.

The gap between the opposing substrate and the substrate varies depending on the application of the liquid crystal display device, but is usually selected in the range of 2 to 8 μm. After bonding with the opposing substrate, the area other than the liquid crystal injection port is sealed with a sealant such as epoxy resin. The sealant is hardened by UV irradiation and/or heating, sealing the periphery of the liquid crystal cell.
The liquid crystal cell with its periphery sealed is then cut into panel units, and the pressure is reduced in a vacuum chamber. The liquid crystal filling port is immersed in liquid crystal, and the liquid crystal is then injected into the liquid crystal cell by leaking the chamber. The degree of pressure reduction in the liquid crystal cell is typically 1×10 ⁻² to 1×10 ⁻⁷ Pa, and preferably 1×10 ⁻³ to 1×10 ⁻⁶ Pa. It is also preferable to heat the liquid crystal cell during the pressure reduction, typically at a temperature of 30 to 100°C, more preferably 50 to 90°C. The heating during the pressure reduction is typically maintained for 10 to 60 minutes, and the cell is then immersed in liquid crystal. The liquid crystal cell with the liquid crystal filled is then sealed by curing a UV-curable resin to complete a liquid crystal display device (panel).

There are no particular restrictions on the type of liquid crystal, and any of the conventionally known liquid crystals, such as aromatic, aliphatic, and polycyclic compounds, as well as lyotropic and thermotropic liquid crystals, may be used. Known thermotropic liquid crystals include nematic, smectic, and cholesteric liquid crystals, and any of these may be used.

[Organic EL display]
The organic EL display of the present invention is produced using the color filter of the present invention or the organic electroluminescent device of the present invention.

When an organic EL display is produced using the color filter of the present invention, for example, as shown in FIG. 1, a color filter having a pattern formed from a photosensitive resin composition (i.e., pixels 20 and a resin black matrix (not shown) between adjacent pixels 20) is first produced on a transparent support substrate 10. Then, an organic light-emitting element 500 is laminated on the color filter via an organic protective layer 30 and an inorganic oxide film 40, thereby producing an organic EL element 100. Note that at least one of the pixels 20 and the resin black matrix is produced using the photosensitive resin composition of the present invention. Examples of methods for laminating the organic light-emitting element 500 include sequentially forming a transparent anode 50, a hole injection layer 51, a hole transport layer 52, a light-emitting layer 53, an electron injection layer 54, and a cathode 55 on the top surface of the color filter, or laminating the organic light-emitting element 500 formed on a separate substrate onto the inorganic oxide film 40. Using the organic EL element 100 thus produced, an organic EL display can be produced by, for example, the method described in "Organic EL Display" (Ohmsha, August 20, 2004, by Shizuo Tokito, Chinaya Adachi, and Hideyuki Murata).

The color filter of the present invention can be applied to both passive-drive organic EL displays and active-drive organic EL displays.

[Method for controlling the molecular weight of a carboxyl group-containing resin]
The method for controlling the molecular weight of a carboxyl group-containing resin of the present invention includes controlling the water content of a first reaction product A-containing liquid obtained by reacting an epoxy compound (a) with an unsaturated monobasic acid (b) in an organic solvent to obtain a second reaction product A-containing liquid, and adding a polybasic acid dianhydride (c) and a polybasic acid monoanhydride (d) to the second reaction product A-containing liquid and reacting them to obtain a carboxyl group-containing resin.
The details are the same as those in steps B and C in the method for producing a carboxyl group-containing resin of the present invention.

When obtaining the carboxyl group-containing resin, the polybasic acid dianhydride (c), the polybasic acid monoanhydride (d), and the polyhydric alcohol (e) may be added to the second reaction product A-containing liquid and reacted to obtain the resin.
The preferred types and preferred blending amounts of the epoxy compound (a), the unsaturated monobasic acid (b), the polybasic acid dianhydride (c), the polybasic acid monoanhydride (d), and the polyhydric alcohol (e) are the same as the types and blending amounts described above in the method for producing a carboxy group-containing resin.
As the organic solvent used in the reaction for obtaining the first reaction product A-containing liquid, the organic solvents used in the method for producing the carboxy group-containing resin of the present invention can be preferably used.

The present invention will be explained in more detail using examples, but the present invention is not limited to the following examples as long as it does not depart from the gist of the invention.

<Examples 1 to 4: Synthesis of carboxyl group-containing resins (1) to (4)>

265 g of the epoxy compound (epoxy equivalent weight 240) having the above structure, 80 g of acrylic acid, 350 g of propylene glycol monomethyl ether acetate (PGMEA), 4 g of triphenylphosphine, and 0.3 g of paramethoxyphenol were placed in a flask equipped with a thermometer, a stirrer, and a condenser, and reacted with stirring at 100° C. until the acid value reached 5 mg KOH/g or less. The reaction took 9 hours, and a first reaction product A-containing liquid containing an intermediate was obtained.
The obtained first reaction product A-containing liquid was cooled to 50°C, and then the water content was measured with a Karl Fischer moisture meter (MKA-610, manufactured by Kyoto Electronics Manufacturing Co., Ltd.). Water was added to the first reaction product A-containing liquid at 50°C with stirring so as to achieve the water content shown in Table 1, thereby controlling the water content of the reaction product A-containing liquid.
To the second reaction product A-containing liquid having the controlled water content, 10 g of trimethylolpropane (TMP), 112 g of biphenyltetracarboxylic dianhydride (BPDA), 105 g of tetrahydrophthalic anhydride (THPA), and 374 g of PGMEA were added to a flask equipped with a thermometer, a stirrer, and a condenser, and the mixture was reacted at 105°C for 20 hours with stirring to obtain carboxyl group-containing resin-containing liquids containing carboxyl group-containing resins (1) to (4), respectively.
The weight average molecular weights (Mw) of the resulting carboxyl group-containing resins (1) to (4) in terms of polystyrene were measured by GPC (2695, manufactured by Waters Corporation) and are shown in Table 1.

Examples 1 to 4 shown in Table 1 show that the weight average molecular weight of the carboxyl group-containing resin can be controlled by including a step of controlling the moisture content of the reaction product A-containing liquid.
As described above, according to the production method of the present invention, it is possible to control the molecular weight of the carboxyl group-containing resin, and it is possible to maintain the performance stability of the carboxyl group-containing resin between production lots.

Claims (18)

a step A of reacting an epoxy compound (a) with an unsaturated monobasic acid (b) in an organic solvent to obtain a liquid containing a first reaction product A;
A step B of controlling the water content of the first reaction product A-containing liquid to obtain a second reaction product A-containing liquid;
and a step C of adding a polybasic acid dianhydride (c) and a polybasic acid monoanhydride (d) to the second reaction product A-containing liquid and reacting them to obtain a carboxy group-containing resin ,
In the step B, water is added to the first reaction product A-containing liquid to control the moisture content of the first reaction product A-containing liquid, thereby obtaining the second reaction product A-containing liquid;
In the step C, the amount of the polybasic acid dianhydride (c) used is 0.5 equivalents or more and 50 equivalents or less relative to 1 equivalent of the polybasic acid monoanhydride (d) . 2. The method for producing a carboxyl group-containing resin according to claim 1 , wherein water is added to the first reaction product A-containing liquid so that the moisture content of the second reaction product A-containing liquid is 0.1 mass % or more and 0.5 mass % or less. The method for producing a carboxyl group-containing resin according to claim 1 or 2 , wherein in step C, a polyhydric alcohol (e) is further added and reacted. The method for producing a carboxyl group-containing resin according to claim 3 , wherein the polyhydric alcohol (e) includes trimethylolpropane. The method for producing a carboxyl group-containing resin according to any one of claims 1 to 4 , wherein the polybasic acid dianhydride (c) includes biphenyltetracarboxylic dianhydride. The method for producing a carboxyl group-containing resin according to any one of claims 1 to 5 , wherein the polybasic acid monoanhydride (d) includes tetrahydrophthalic anhydride. A method for producing an ink containing (A) an alkali-soluble resin, an organic solvent, and (D) a colorant, the method comprising the steps of:
A method for producing an ink, comprising blending a carboxyl group-containing resin produced by the method according to any one of claims 1 to 6 as the alkali-soluble resin (A). A method for producing a photosensitive resin composition comprising (A) an alkali-soluble resin, (B) a photopolymerizable monomer, and (C) a photopolymerization initiator, the method comprising:
A method for producing a photosensitive resin composition, comprising blending a carboxy group-containing resin produced by the production method according to any one of claims 1 to 6 as the alkali-soluble resin (A). The method for producing a photosensitive resin composition according to claim 8 , wherein the photosensitive resin composition further contains (D) a colorant. A method for producing a cured product, comprising curing a photosensitive resin composition obtained by the method according to claim 8 or 9 . A method for producing a black matrix, comprising forming a black matrix using the cured product obtained by the method for producing a black matrix according to claim 10 . A method for producing an image display device, comprising using a cured product obtained by the method according to claim 10 or a black matrix obtained by the method according to claim 11 . A method for controlling the molecular weight of a carboxyl group-containing resin, comprising: controlling the water content of a first reaction product A-containing liquid obtained by reacting an epoxy compound (a) with an unsaturated monobasic acid (b) in an organic solvent to obtain a second reaction product A-containing liquid; and adding a polybasic acid dianhydride (c) and a polybasic acid monoanhydride (d) to the second reaction product A-containing liquid and reacting them to obtain a carboxyl group-containing resin. 14. The method for controlling the molecular weight of a carboxy group-containing resin according to claim 13, wherein the second reaction product A-containing liquid is obtained by adding water to the first reaction product A-containing liquid to control the moisture content of the first reaction product A-containing liquid so that the moisture content of the solution containing the second reaction product A-containing liquid is 0.1 mass % or more and 0.5 mass % or less. 15. The method for controlling the molecular weight of a carboxyl group-containing resin according to claim 13 or 14, wherein the carboxyl group-containing resin is a carboxyl group-containing resin obtained by adding a polybasic acid dianhydride (c), a polybasic acid monoanhydride (d), and a polyhydric alcohol (e) to the second reaction product A-containing liquid and allowing the mixture to react. The method for controlling the molecular weight of a carboxy group-containing resin according to claim 15 , wherein the polyhydric alcohol (e) includes trimethylolpropane. The method for controlling the molecular weight of a carboxy group-containing resin according to any one of claims 13 to 16 , wherein the polybasic acid dianhydride (c) comprises biphenyltetracarboxylic dianhydride. The method for controlling the molecular weight of a carboxy group-containing resin according to any one of claims 13 to 17 , wherein the polybasic acid monoanhydride (d) includes tetrahydrophthalic anhydride.