Block copolymer, dispersant, and coloring composition

Abstract

[Problem] To provide a block copolymer that, when being used as a dispersant for a coloring composition, exhibits a high dispersion performance of a colorant, and that can improve alkali developability of the obtained coloring composition. [Solution] This block copolymer has an A-block and a B-block, and is characterized in that: the A-block substantially does not include a structural unit (b-1) having a cyano group or a structural unit (b-2) having a basic group; the B-block includes the structural unit (b-1) having a cyano group and the structural unit (b-2) having a basic group; the content of the structural unit (b-1) with respect to 100 mol% of structural units forming the B-block is 1-50 mоl%; and the mole ratio ((b-1) / (b-2)) of the structural unit (b-1) and the structural unit (b-2) in the B-block is 0.01-1.0.

Description

Block copolymer, dispersant, and colored composition

[0001] The present invention relates to block copolymers, and more particularly to block copolymers that can be used as dispersants for colorants in colored compositions.

[0002] Conventionally, in the manufacture of color filters used in liquid crystal displays and the like, methods for applying colorants to substrates include dyeing, printing, inkjet, electrodeposition, and pigment dispersion. Among these, pigment dispersion has become the mainstream method from the viewpoint of spectral characteristics, durability, pattern shape, and accuracy. In this pigment dispersion method, a coating film consisting of a colored composition mixed with pigment, dispersant, dispersion medium, binder resin, etc., is formed on a substrate, cured by irradiation with ultraviolet light through a photomask with a desired pattern shape, and then alkaline development is performed.

[0003] In recent years, increasing the concentration of pigments in coloring compositions has been investigated to obtain good color reproduction and high contrast in color filters. When the pigment concentration is increased, the proportion of dispersant decreases relatively, so the dispersant needs to have high dispersibility (see, for example, Patent Document 1 (paragraph 0004)). In addition, in alkaline development, alkali-soluble binder resins play a major role.

[0004] However, in the case of colored compositions with high pigment concentrations, the proportion of binder resin, which is a developing component, decreases, and the alkali developability deteriorates. Therefore, there is a need for a dispersant that can improve the alkali developability of colored compositions. As such a dispersant, a block copolymer consisting of a solvent affinity block having a hydroxyl group and / or alkoxy group and a colorant affinity block having a nitrogen-containing functional group is used (see Patent Document 2 (paragraphs 0243, 0244) and Patent Document 3 (claim 1)).

[0005] Furthermore, with the increasing concentration of colorants in recent years, there is a demand for further improvement in dispersion performance. It has been proposed that by introducing a predetermined chain-like hydrocarbon group into the colorant affinity block, steric hindrance to basic groups can be controlled, making it easier for basic groups to adsorb to the colorant and thus improving the dispersion performance of the colorant (see Patent Document 4 (paragraphs 0007, 0008)).

[0006] Japanese Patent Publication No. 2009-265515, Japanese Patent Publication No. 2009-52010, Japanese Patent Publication No. 2013-119568, International Publication No. 2024 / 116875

[0007] The block copolymer described in Patent Document 4 has excellent dispersion performance for colorants, but when used as a dispersant for a colored composition with a high concentration of colorant, the resulting colored composition did not have sufficient alkali developability. The present invention has been made in view of the above circumstances, and aims to provide a block copolymer that, when used as a dispersant for a colored composition, has high dispersion performance for colorants and can improve the alkali developability of the resulting colored composition.

[0008] The block copolymer of the present invention, which has been able to solve the above problems, is a block copolymer having an A block and a B block, wherein the A block substantially does not contain structural units having a cyano group (b-1) and structural units having a basic group (b-2), the B block contains structural units having a cyano group (b-1) and structural units having a basic group (b-2), the content of structural units having a cyano group (b-1) in 100 mol% of the structural units constituting the B block is 1 mol% to 50 mol%, and the molar ratio ((b-1) / (b-2)) of the structural units (b-1) to the structural units (b-2) in the B block is 0.01 to 1.0.

[0009] The reason why the block copolymer of the present invention exhibits high dispersion performance of the colorant and improved alkali developability of the resulting colored composition is thought to be as follows. The block copolymer of the present invention is designed such that block A has high affinity with the dispersion medium and block B has high affinity with the colorant, and the basic groups introduced into block B are adsorbed onto the colorant. Here, by keeping the molar ratio of highly polar structural units (b-1) and structural units (b-2) in block B within a predetermined range, the affinity with the alkaline developer is increased, and alkali developability is improved. Furthermore, by keeping the molar ratio of structural units (b-1) and structural units (b-2) in block B within a predetermined range, the spacing of the introduced basic groups can be adjusted. As a result, the basic groups introduced into block B are more easily adsorbed onto the colorant, further improving the dispersion performance of the colorant.

[0010] The block copolymer of the present invention, when used as a dispersant for a colored composition, exhibits high dispersion performance of the coloring agent and can improve the alkali developability of the resulting colored composition.

[0011] The following describes an example of a preferred embodiment of the present invention. However, the following embodiments are merely illustrative. The present invention is not limited in any way to the following embodiments.

[0012] <Definitions> In this specification, "(meth)acrylic" means "at least one of acrylic and methacrylic." "(meth)acrylate" means "at least one of acrylate and methacrylate," and is also an ester compound in which the hydrogen atom of the carboxyl group of (meth)acrylic acid is replaced with an organic group. "(meth)acryloyl" means "at least one of acryloyl and methacryloyl." "(meth)acrylic monomer" means "a monomer having a (meth)acryloyl group in its molecule," and also includes "(meth)acrylate." "Vinyl monomer" means "a monomer having a radically polymerizable carbon-carbon double bond in its molecule," and also includes "(meth)acrylate" and "(meth)acrylic monomer."

[0013] In this specification, "structural unit derived from (meth)acrylate" means "a structural unit in which the radically polymerizable carbon-carbon double bond of (meth)acrylate polymerizes to form a carbon-carbon single bond." "Structural unit derived from (meth)acrylic monomer" means "a structural unit in which the radically polymerizable carbon-carbon double bond of (meth)acrylic monomer polymerizes to form a carbon-carbon single bond." "Structural unit derived from vinyl monomer" means "a structural unit in which the radically polymerizable carbon-carbon double bond of vinyl monomer polymerizes to form a carbon-carbon single bond."

[0014] In this specification, "X to Y" (where X and Y are any numbers) means "greater than or equal to X and less than or equal to Y". Furthermore, "greater than or equal to X" (where X is any number) also includes "X or greater than X", and "less than or equal to Y" (where Y is any number) also includes "Y or less than Y". In addition, "X and / or Y (where X and Y are any combination)" means "at least one of X and Y", and has three possible combinations: "X only", "Y only", and "X and Y".

[0015] <Block Copolymer> The block copolymer of the present invention is a block copolymer containing Block A and Block B. In this specification, "Block A" can be replaced with "Segment A," and "Block B" can be replaced with "Segment B."

[0016] (Block B) Block B is a block containing a structural unit (b-1) having a cyano group (-CN) and a structural unit (b-2) having a basic group.

[0017] (Cyano group-containing structural unit (b-1)) The B block contains a cyano group-containing structural unit (b-1), which allows for maintaining high polarity of the entire adsorption site due to the high polarity of the structural unit (b-1), and also allows for appropriate control of the distance and orientation between the structural units (b-2). The structural unit (b-1) may consist of only one type or may consist of two or more types. Examples of the structural unit (b-1) include structures derived from vinyl monomers containing cyano groups.

[0018] The structural unit (b-1) is preferably the structural unit represented by formula (1). The structural unit represented by formula (1) does not have the basic group described later.

[0019] [In equation (1), R 11 represents a hydrogen atom or a methyl group. A 11 This represents a single bond or a divalent linking group.

[0020] A 11 The divalent linking groups represented by include linear alkylene groups having 1 to 10 carbon atoms, branched alkylene groups having 3 to 10 carbon atoms, cyclic alkylene groups having 6 to 12 carbon atoms, arenediyl groups having 6 to 12 carbon atoms, and ester groups (-CO-O-R). 111 Examples include -). The bonding direction of the ester group is not particularly limited, but the bonding configuration of the ester group is C-CO-O-R. 111 -CN is preferred.

[0021] R 111 Examples of alkylene groups include linear alkylene groups, branched alkylene groups, cyclic alkylene groups, and arenediyl groups, with arenediyl groups being preferred from the viewpoint of heat resistance. The linear alkylene group preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and examples include methylene groups, ethylene groups, trimethylene groups, tetramethylene groups, and pentamethylene groups. The branched alkylene group preferably has 3 to 10 carbon atoms, and examples include propylene groups, propyridene groups, 1,2-butanediyl groups, and 1,3-butanediyl groups. The cyclic alkylene group may have a chain portion, preferably 6 to 12 carbon atoms, and examples include cyclopropylene groups, cyclobutylene groups, cyclopentylene groups, and cyclohexylene groups. The arenediyl group may have a chain portion, preferably 6 to 12 carbon atoms, and examples include phenylene groups. A 11 From a polarity standpoint, a single bond is preferable.

[0022] Specific examples of the vinyl monomer that forms the structural unit represented by the formula (1) include (meth)acrylonitrile, cyanomethyl (meth)acrylate, cyanoethyl (meth)acrylate, 4-cyanostyrene, 4-cyano-α-methylstyrene, and the like.

[0023] The content of the structural unit (b-1) is preferably 1 mol% or more, more preferably 3 mol% or more, still more preferably 10 mol% or more, and preferably 50 mol% or less, more preferably 40 mol% or less, still more preferably 30 mol% or less in 100 mol% of the structural units constituting the B block. When the content of the structural unit (b-1) is within the above range, when used as a dispersant for the coloring composition, the dispersing performance of the colorant is high, and the alkali developability of the resulting coloring composition can be improved. Further, from the viewpoint of the heat resistance of the block copolymer, the content of the structural unit (b-1) is preferably 25 mol% or less in 100 mol% of the structural units constituting the B block.

[0024] (Structural unit (b-2) having a basic group) The B block has a high affinity for the colorant by containing a structural unit (b-2) having a basic group. The structural unit (b-2) may be only one kind or may have two or more kinds.

[0025] The basic group is a group showing basicity, and is preferably an amino group in view of the availability of raw materials and ease of synthesis. In the present specification, the amino group includes, in addition to a general amino group (—NH2), —NHR in which H is substituted by a hydrocarbon group, a , —NR a R b (R a , R b each independently represents a chain or cyclic hydrocarbon group. Further, R a and R b may be bonded to each other to form a cyclic structure.) Substituted amino groups represented by, and nitrogen-containing heterocyclic groups (piperidyl group, pyridyl group, imidazole group, etc.) and the like are included. Examples of the structural unit (b-2) include a structure derived from a vinyl monomer having a basic group.

[0026] The structural unit (b-2) is preferably the structural unit represented by formula (2). Note that the structural unit represented by formula (2) does not have a cyano group.

[0027] [In equation (2), R 21 represents a hydrogen atom or a methyl group. A 21 R represents a single bond or a divalent linking group. 22 and R 23 Each of these independently represents a hydrocarbon group that may contain heteroatoms. 22 and R 23 These may be joined together to form a ring structure.

[0028] A 21 The divalent linking groups represented by include linear alkylene groups having 1 to 10 carbon atoms, branched alkylene groups having 3 to 10 carbon atoms, cyclic alkylene groups having 6 to 12 carbon atoms, arenediyl groups having 6 to 12 carbon atoms, and ester groups (-CO-O-R). 211 -), amide group (-CO-NH-R 212 Examples include -). The bonding direction of the ester group and amide group is not particularly limited, but the bonding configuration of the ester group is C-CO-O-R. 211 -N is preferred, and the bonding configuration of the amide group is C-CO-NH-R 212 -N is preferred.

[0029] R 211 and R 212Examples include linear alkylene groups, branched alkylene groups, cyclic alkylene groups, and arenediyl groups, with linear alkylene groups being preferred. The linear alkylene group preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and examples include methylene groups, ethylene groups, trimethylene groups, tetramethylene groups, and pentamethylene groups. The branched alkylene group preferably has 3 to 10 carbon atoms, and examples include propylene groups, propyridene groups, 1,2-butanediyl groups, and 1,3-butanediyl groups. The cyclic alkylene group may have a chain portion, preferably 6 to 12 carbon atoms, and examples include cyclopropylene groups, cyclobutylene groups, cyclopentylene groups, and cyclohexylene groups. The arenediyl group may have a chain portion, preferably 6 to 12 carbon atoms, and examples include phenylene groups. 21 The linking group is preferably a divalent group, and ester groups and amide groups are more preferred from the viewpoint of affinity with the dispersion medium and binder resin.

[0030] R 22 and R 23Hydrocarbon groups that may contain heteroatoms represented by include linear hydrocarbon groups and cyclic hydrocarbon groups, with linear hydrocarbon groups being preferred. A hydrocarbon group containing a heteroatom has a structure in which carbon atoms in the hydrocarbon group are replaced by heteroatoms. Examples of heteroatoms that the hydrocarbon group may contain include oxygen atoms. Examples of linear hydrocarbon groups include linear alkyl groups and branched alkyl groups, with linear alkyl groups being preferred. The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 1 to 5 carbon atoms, such as methyl groups, ethyl groups, n-propyl groups, and n-butyl groups. The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 10 carbon atoms, and even more preferably 3 to 5 carbon atoms, such as isopropyl groups, isobutyl groups, sec-butyl groups, and tert-butyl groups. Examples of cyclic hydrocarbon groups include cyclic alkyl groups and aromatic groups. The cyclic alkyl group may have a chain-like portion, preferably having 4 to 18 carbon atoms, more preferably 6 to 12 carbon atoms, and even more preferably 6 to 10 carbon atoms. Examples include cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, and cyclooctyl group. The aromatic group may have a chain-like portion, preferably having 6 to 18 carbon atoms, more preferably 6 to 12 carbon atoms, and even more preferably 6 to 8 carbon atoms. Examples include phenyl group, tolyl group, xylyl group, and mesityl group.

[0031] R 22 and R 23 The fact that they are bonded to each other to form a ring structure means that R 22 and R 23 This refers to the formation of a cyclic structure via a nitrogen atom. Examples of such cyclic structures include nitrogen-containing heterocycles with 5 to 7 members or fused rings formed by the fusion of two such heterocycles. Specifically, examples include structures represented by the following formulas (2-1), (2-2), and (2-3).

[0032] [In equations (2-1), (2-2), and (2-3), R 24* represents an alkyl group with 1 to 6 carbon atoms. l represents an integer from 0 to 5. m represents an integer from 0 to 4. n represents an integer from 0 to 4. * represents a bond. When l is 2 to 5, m is 2 to 4, and n is 2 to 4, there are multiple R groups. 24 These may be the same or different.

[0033] Specific examples of vinyl monomers that form the structural unit represented by formula (2) include dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, dimethylaminobutyl (meth)acrylate, diethylaminoethyl (meth)acrylate, diethylaminopropyl (meth)acrylate, diethylaminobutyl (meth)acrylate, ethylaminoethyl (meth)acrylate, ethylaminopropyl (meth)acrylate, ethylaminobutyl (meth)acrylate, propylaminoethyl (meth)acrylate, propylaminopropyl (meth)acrylate, propylaminobutyl (meth)acrylate, dimethylaminopropyl (meth)acrylamide, and the like.

[0034] The content of the structural unit (b-2) is preferably 10 mol% or more, more preferably 30 mol% or more, even more preferably 50 mol% or more, preferably 99 mol% or less, more preferably 97 mol% or less, and even more preferably 90 mol% or less, out of 100 mol% of the structural units constituting block B. If the content of the structural unit (b-2) is within the above range, when used as a dispersant for a colored composition, the dispersion performance of the coloring agent is high, and the alkali developability of the resulting colored composition can be improved.

[0035] The molar ratio ((b-1) / (b-2)) of the structural unit (b-1) to the structural unit (b-2) in block B is preferably 0.01 or more, more preferably 0.03 or more, even more preferably 0.10 or more, preferably 1.0 or less, more preferably 0.7 or less, and even more preferably 0.4 or less. If the molar ratio ((b-1) / (b-2)) is within the above range, when used as a dispersant for a colored composition, the dispersion performance of the coloring agent is high, and the alkali developability of the resulting colored composition can be improved.

[0036] In 100 mol% of the structural units constituting block B, the total content of structural unit (b-1) and structural unit (b-2) ((b-1) + (b-2)) is preferably 11 mol% or more, more preferably 50 mol% or more, even more preferably 85 mol% or more, and particularly preferably 95 mol% or more. If the total content ((b-1) + (b-2)) is 11 mol% or more, when used as a dispersant for a colored composition, the dispersion performance of the coloring agent is high, and the alkali developability of the resulting colored composition can be improved. The upper limit of the total content ((b-1) + (b-2)) is 100 mol%.

[0037] In addition to the structural units (b-1) and (b-2), the B block may also contain a structural unit (b-3) having a salt of a basic group. The presence of the structural unit (b-3) allows for the maintenance of strong adsorption to the coloring material surface over a long period, further improving storage stability. The structural unit (b-3) may consist of only one type or may consist of two or more types.

[0038] If the B block contains a structural unit (b-3) having a salt of a basic group in addition to the structural units (b-1) and (b-2), the total content of structural units (b-1) + (b-2) + (b-3) in 100 mol% of the structural units constituting the B block is preferably 11 mol% or more, more preferably 50 mol% or more, even more preferably 85 mol% or more, and particularly preferably 95 mol% or more. The upper limit of the total content (b-1) + (b-2) + (b-3) is 100 mol%. Furthermore, the molar ratio of structural unit (b-3) to structural unit (b-2) in the B block (b-3 / b-2) is preferably 0.1 or more, and preferably 1.0 or less.

[0039] Examples of basic group salts include halogenated salts of basic groups (F, Cl, Br, I, etc.), inorganic salts such as sulfates, and sulfonates, sulfates, phosphates, or carboxylates of organic compounds. As for basic group salts, amino group salts are preferred due to the ease of obtaining raw materials and synthesis. In this specification, quaternary ammonium group (-NR) is used as an example of an amino group salt. c R d R e (R c , R d and R e Each of these independently represents a chain-like or cyclic hydrocarbon group. Also, R c , R d and R e Two or more of these may be bonded to each other to form a cyclic structure. This also includes salts of (e.g., halides). Furthermore, structural unit (b-3) having a salt of a basic group may be formed when a portion of the basic group of structural unit (b-2) has formed a salt.

[0040] The B block may contain other structural units other than the structural unit (b-1), the structural unit (b-2), and the structural unit (b-3) to the extent that it does not impair the effects of the present invention. Specific examples of monomers that can form other structural units of the B block are the same as those exemplified later as monomers that can form structural units of the A block and monomers that can form other structural units.

[0041] The various structural units contained in the B block may be contained in the B block in any manner, such as random copolymerization or block copolymerization, and it is preferable that they be contained in a manner of random copolymerization from the viewpoint of uniformity. For example, the B block may be formed by a copolymer of structural units consisting of block b1 and structural units consisting of block b2.

[0042] (Block A) Block A is a block that substantially does not contain structural units (b-1) having a cyano group (-CN) and structural units (b-2) having a basic group. In other words, it is preferable that the vinyl monomer constituting Block A substantially does not contain vinyl monomers having a cyano group and vinyl monomers having a basic group. If cyano groups and basic groups are present in Block A, when used as a dispersant, the coloring agent will be adsorbed onto both Block A and Block B, reducing the dispersion performance of the coloring agent. It is said that Block A substantially does not contain structural units (b-1) having a cyano group and structural units (b-2) having a basic group, which means that the total content of structural units (b-1) having a cyano group and structural units (b-2) having a basic group in 100 mol% of the structural units constituting Block A is 3 mol% or less, preferably 1 mol% or less, and more preferably 0 mol%.

[0043] Examples of structural units constituting block A include structural units derived from (meth)acrylic monomers and structural units derived from vinyl monomers other than (meth)acrylic monomers. Block A may consist of only one type of structural unit, or it may consist of two or more types.

[0044] Examples of (meth)acrylic monomers that form structural units derived from the (meth)acrylic monomer include (meth)acrylic monomers having a chain alkyl group, (meth)acrylic monomers having a cyclic alkyl group, (meth)acrylic monomers having an aryl group, (meth)acrylic monomers having a hydroxyl group, (meth)acrylic monomers having an alkoxy group, (meth)acrylic monomers having an oxygen-containing heterocyclic group, (meth)acrylic monomers having an amide group, and (meth)acrylic monomers having an acidic group.

[0045] Examples of the (meth)acrylic monomer having a linear alkyl group include (meth)acrylate having a linear alkyl group and (meth)acrylate having a branched alkyl group. The linear alkyl group of the (meth)acrylate having a linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms. Specific examples of the (meth)acrylate having a linear alkyl group include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, n-lauryl (meth)acrylate, and n-stearyl (meth)acrylate. The branched alkyl group of the (meth)acrylate having a branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 10 carbon atoms. Specific examples of (meth)acrylates having the branched alkyl group include isopropyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isononyl (meth)acrylate, and isodecyl (meth)acrylate.

[0046] Examples of the (meth)acrylic monomer having a cyclic alkyl group include (meth)acrylates having a monocyclic cyclic alkyl group and (meth)acrylates having a cyclic alkyl group having a crosslinked ring structure. The monocyclic cyclic alkyl group of the (meth)acrylate having a monocyclic cyclic alkyl group preferably has 6 to 12 carbon atoms. Specific examples of the (meth)acrylate having a monocyclic cyclic alkyl group include cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, and cyclododecyl (meth)acrylate. The cyclic alkyl group having a crosslinked ring structure of the (meth)acrylate having a cyclic alkyl group having a crosslinked ring structure preferably has 6 to 12 carbon atoms. Specific examples of (meth)acrylates having a cyclic alkyl group with a cross-linking ring structure include isobornyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentanyloxyethyl (meth)acrylate, 2-methyl-2-adamantyl (meth)acrylate, and 2-ethyl-2-adamantyl (meth)acrylate.

[0047] The aryl group of the (meth)acrylic monomer having the aryl group preferably has 6 to 12 carbon atoms and may have a chain-like portion such as an alkylaryl group, aralkyl group, or aryloxyalkyl group. Specific examples of the (meth)acrylate having the aryl group include benzyl (meth)acrylate, phenyl (meth)acrylate, and phenoxyethyl (meth)acrylate.

[0048] Examples of the (meth)acrylic monomer having a hydroxyl group include (meth)acrylate having a hydroxyalkyl group, (meth)acrylate having a lactone-modified hydroxyl group, and (meth)acrylate having a hydroxypolyalkylene glycol group. The hydroxyalkyl group of the (meth)acrylate having a hydroxyalkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms. The hydroxyalkyl group is preferably linear or branched. Specific examples of the (meth)acrylate having a hydroxyalkyl group include 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, and 12-hydroxylauryl (meth)acrylate. Examples of the (meth)acrylate having a lactone-modified hydroxyl group include (meth)acrylate having a hydroxyalkyl group to which a lactone has been added, with caprolactone being preferred. The amount of caprolactone added is preferably 1 mol to 20 mol, more preferably 1 mol to 10 mol. Specific examples of the lactone-modified hydroxyl group-containing (meth)acrylate include a 1 mol adduct of caprolactone to 2-hydroxyethyl (meth)acrylate, a 2 mol adduct of caprolactone to 2-hydroxyethyl (meth)acrylate, a 3 mol adduct of caprolactone to 2-hydroxyethyl (meth)acrylate, a 4 mol adduct of caprolactone to 2-hydroxyethyl (meth)acrylate, a 5 mol adduct of caprolactone to 2-hydroxyethyl (meth)acrylate, and a 10 mol adduct of caprolactone to 2-hydroxyethyl (meth)acrylate. Examples of the hydroxypolyalkylene glycol-containing (meth)acrylate include terminal hydroxyl group polyethylene glycol (degree of polymerization = 2 to 30) mono(meth)acrylate and terminal hydroxyl group polypropylene glycol (degree of polymerization = 2 to 30) mono(meth)acrylate.

[0049] Examples of (meth)acrylic monomers having an alkoxy group include (meth)acrylates having an alkoxyalkyl group and (meth)acrylates having an alkoxypolyalkylene glycol group. Examples of (meth)acrylates having an alkoxyalkyl group include methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate. Examples of (meth)acrylates having an alkoxypolyalkylene glycol group include (meth)acrylates having an alkoxypolyethylene glycol group such as polyethylene glycol (degree of polymerization = 2 to 30) methyl ether (meth)acrylate, polyethylene glycol (degree of polymerization = 2 to 30) ethyl ether (meth)acrylate, and polyethylene glycol (degree of polymerization = 2 to 30) propyl ether (meth)acrylate; and (meth)acrylates having an alkoxypolypropylene glycol group such as polypropylene glycol (degree of polymerization = 2 to 30) methyl ether (meth)acrylate, polypropylene glycol (degree of polymerization = 2 to 30) ethyl ether (meth)acrylate, and polypropylene glycol (degree of polymerization = 2 to 30) propyl ether (meth)acrylate.

[0050] The oxygen-containing heterocyclic group of the (meth)acrylic monomer having the oxygen-containing heterocyclic group is preferably a 4-membered to 6-membered ring. Specific examples of the (meth)acrylic monomer having the oxygen-containing heterocyclic group include glycidyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl (meth)acrylate, cyclic trimethylolpropaneformal (meth)acrylate, and 2-[(2-tetrahydropyranyl)oxy]ethyl (meth)acrylate.

[0051] Examples of (meth)acrylic monomers having the amide group include N,N-dimethyl(meth)acrylamide and 4-(meth)acryloylmorpholin.

[0052] Examples of acidic groups found in the (meth)acrylic monomer having the aforementioned acidic group include carboxyl group (-COOH), sulfonic acid group (-SO3H), phosphate group (-OPO3H2), phosphonic acid group (-PO3H2), and phosphinic acid group (-PO2H2). Specific examples of the (meth)acrylic monomer having the acidic group include (meth)acrylic acid; (meth)acrylates having a carboxyl group such as 2-(meth)acryloyloxy)ethyl hydrogen succinate, 2-(meth)acryloyloxy)ethyl hydrogen hexahydrophthalate, 2-(meth)acryloyloxy)ethyl hydrogen phthalate, 2-carboxyethyl (meth)acrylic acid, and caprolactone adducts of (meth)acrylic acid; (meth)acrylates having a phosphate group such as 2-(phosphonooxy)ethyl (meth)acrylic acid; and (meth)acrylates having a sulfonic acid group such as 2-sulfoethyl (meth)acrylic acid and 2-(meth)acrylamido-2-methylpropanesulfone. Preferably, (meth)acrylic acid and (meth)acrylates having a carboxyl group are used.

[0053] The structural units derived from vinyl monomers other than the (meth)acrylic monomers mentioned above are not particularly limited as long as they are formed from vinyl monomers that can copolymerize with both the (meth)acrylic monomer and the vinyl monomers that form the aforementioned B block. Examples of vinyl monomers that form structural units derived from vinyl monomers other than the (meth)acrylic monomers include α-olefins, styrene monomers, vinyl monomers having hydroxyl groups, vinyl monomers having heterocyclic structures, vinyl amides, vinyl carboxylates, dienes, etc. Examples of the α-olefins include 1-hexene, 1-octene, 1-decene, etc. Examples of the styrene monomers include substituted or unsubstituted styrene. Examples of substituents that may be substituted on styrene include alkyl groups, aryl groups, alkoxy groups, aryloxy groups, etc. Furthermore, styrene monomers also include fused ring compounds in which two or more benzene rings are fused. Specific examples of the styrene monomers include styrene, α-methylstyrene, 4-methylstyrene, 2-methylstyrene, 3-methylstyrene, 2,4-dimethylstyrene, 4-methoxystyrene, 4-phenylstyrene, 2-hydroxymethylstyrene, 1-vinylnaphthalene, etc. Examples of vinyl monomers having a hydroxyl group include 4-vinylphenol and 4-hydroxybutyl vinyl ether. Examples of vinyl monomers having a heterocycle include 2-vinylthiophene, N-methyl-2-vinylpyrrole, and 1-vinyl-2-pyrrolidone. Examples of vinyl amides include N-vinylformamide, N-vinylacetamide, and N-vinyl-ε-caprolactam. Examples of vinyl carboxylates include vinyl acetate, vinyl pivalate, and vinyl benzoate. Examples of dienes include butadiene, isoprene, 4-methyl-1,4-hexadiene, and 7-methyl-1,6-octadiene.

[0054] The A block preferably contains structural units derived from (meth)acrylic monomers, and more preferably contains at least one structural unit selected from the group consisting of (meth)acrylic monomers having a chain alkyl group, (meth)acrylic monomers having a cyclic alkyl group, (meth)acrylic monomers having an aryl group, (meth)acrylic monomers having a hydroxyl group, (meth)acrylic monomers having an alkoxy group, (meth)acrylic monomers having an oxygen-containing heterocyclic group, (meth)acrylic monomers having an amide group, and (meth)acrylic monomers having an acidic group. Including these structural units further improves the affinity with the binder resin blended into the dispersion medium and colored composition.

[0055] The content of structural units derived from (meth)acrylic monomer is preferably 80 mol% or more, more preferably 90 mol% or more, and even more preferably 95 mol% or more, out of 100 mol% of structural units constituting Block A. Block A may consist only of structural units derived from (meth)acrylic monomer.

[0056] The A block preferably contains at least one structural unit selected from the group consisting of a structural unit (a-1) derived from a (meth)acrylate having a hydroxyl group and a structural unit (a-2) derived from a (meth)acrylate having an alkoxy group. The presence of a hydroxyl group or an alkoxy group in the A block can further enhance the alkali developability of the colored composition using the block copolymer.

[0057] If the A block contains structural units (a-1) derived from a (meth)acrylate having a hydroxyl group and / or structural units (a-2) derived from a (meth)acrylate having an alkoxy group, the total content of these units ((a-1) + (a-2)) is preferably 1 mol% or more, more preferably 2 mol% or more, even more preferably 3 mol% or more, preferably 70 mol% or less, more preferably 60 mol% or less, and even more preferably 50 mol% or less, out of 100 mol% of the structural units constituting the A block. By setting the total content ((a-1) + (a-2)) within the above range, the alkali developability of the colored composition using the block copolymer can be further improved.

[0058] The A block more preferably contains a structural unit (a-1) derived from a (meth)acrylate having a hydroxyl group, and even more preferably contains a structural unit derived from a (meth)acrylate having a lactone-modified hydroxyl group or a structural unit derived from a (meth)acrylate having a hydroxyalkyl group. The structural unit derived from a (meth)acrylate having a lactone-modified hydroxyl group has an ester bond portion and a terminal hydroxyl group in its side chain, and therefore has a high affinity for the dispersion medium and binder resin, further improving the alkali developability of the colored composition using the block copolymer in the dispersion medium. The structural unit derived from a (meth)acrylate having a hydroxyalkyl group has a terminal hydroxyl group in its side chain, and therefore has a high affinity for the dispersion medium and binder resin, further improving the alkali developability of the colored composition using the block copolymer in the dispersion medium.

[0059] As the structural unit derived from the (meth)acrylate having the lactone-modified hydroxyl group, the structural unit represented by formula (3) is preferred.

[0060] [In equation (3), n1 represents an integer from 1 to 10. R 31 R represents a hydrogen atom or a methyl group. 32 R represents an alkylene group with 1 to 10 carbon atoms. 33R represents an alkylene group with 1 to 10 carbon atoms. Note that if n1 is 2 or more, there may be multiple R groups. 33 These may be the same or different.

[0061] In equation (3), n1 is preferably an integer from 1 to 7, more preferably an integer from 1 to 5. 32 The alkylene group represented by may be linear or branched, but linear is preferred. 32 Specific examples of alkylene groups represented by include methylene group, ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group, nonamethylene group, decamethylene group, and 1-methylethylene group. 32 The alkylene group represented by preferably has 1 to 5 carbon atoms.

[0062] R 33 The alkylene group represented by may be linear or branched, but linear is preferred. 33 Specific examples of alkylene groups represented by R include methylene group, ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group, nonamethylene group, decamethylene group, etc. 33 The alkylene group represented by preferably has 1 to 8 carbon atoms, more preferably 3 to 8 carbon atoms.

[0063] If the A block contains structural units (a-1) derived from (meth)acrylate having a hydroxyl group, the content of these units is preferably 1 mol% or more, more preferably 3 mol% or more, even more preferably 5 mol% or more, preferably 70 mol% or less, more preferably 60 mol% or less, and even more preferably 50 mol% or less, out of 100 mol% of the structural units constituting the A block. By setting the content of structural units (a-1) derived from (meth)acrylate having a hydroxyl group within the above range, the alkali developability of the colored composition containing the block copolymer is further improved.

[0064] The A block preferably contains structural units (a-2) derived from (meth)acrylate having an alkoxy group, and more preferably contains structural units derived from (meth)acrylate having an alkoxypolyalkylene glycol group. The structural units derived from (meth)acrylate having an alkoxyalkylene glycol group have an ether bond and a terminal alkoxy group in their side chains, and therefore have high affinity with the dispersion medium and binder resin, further improving the alkali developability of the colored composition using the block copolymer in the dispersion medium.

[0065] As the structural unit derived from the (meth)acrylate having an alkoxypolyalkylene glycol group, the structural unit represented by formula (4) is preferred.

[0066] [In equation (4), n² represents an integer between 2 and 30. R 41 R represents a hydrogen atom or a methyl group. 42 R represents an alkylene group with 1 to 3 carbon atoms. 43 R represents an alkylene group with 1 to 3 carbon atoms. Note that there are multiple R groups. 43 These may be the same or different. 44 This represents an alkyl group with 1 to 3 carbon atoms.

[0067] In formula (4), n2 is 2 or more, preferably 5 or more, and 30 or less, preferably 20 or less, and even more preferably 15 or less. 42 , R 43 The alkylene group having 1 to 3 carbon atoms, as indicated by R, may be linear or branched, but linear is preferred. 42 The alkylene group having 1 to 3 carbon atoms as indicated by is preferably an ethylene group or a trimethylene group. 43 The alkylene group having 1 to 3 carbon atoms as indicated by is preferably an ethylene group or a trimethylene group. 44 The alkyl group having 1 to 3 carbon atoms, as shown, may be linear or branched, but linear is preferred. 44Specific examples of alkyl groups having 1 to 3 carbon atoms, as shown, include the methyl group, ethyl group, n-propyl group, and isopropyl group.

[0068] If the A block contains structural units (a-2) derived from (meth)acrylate having an alkoxy group, the content of these units is preferably 1 mol% or more, more preferably 2 mol% or more, even more preferably 3 mol% or more, preferably 70 mol% or less, more preferably 60 mol% or less, and even more preferably 50 mol% or less, out of 100 mol% of the structural units constituting the A block. By setting the content of structural units (a-2) derived from (meth)acrylate having an alkoxy group within the above range, the alkali developability of the colored composition containing the block copolymer is further improved.

[0069] The A block may have structural units (a-3) derived from a vinyl monomer having an acidic group (preferably a (meth)acrylic monomer having an acidic group, more preferably (meth)acrylic acid). Having structural units (a-3) derived from a vinyl monomer having an acidic group further increases solubility in alkaline developers and further improves the alkaline developability of the colored composition. However, if the proportion of these units is too high, the affinity with the dispersion medium and binder resin may decrease. Therefore, it is preferable that the proportion of structural units (a-3) derived from a vinyl monomer having an acidic group be such that the overall acid value of the block copolymer is lower than the amine value.

[0070] When structural units (a-3) derived from vinyl monomers having acidic groups are present, their content is preferably 5 mol% or more, more preferably 10 mol% or more, preferably 30 mol% or less, and more preferably 20 mol% or less, out of 100 mol% of structural units constituting block A. If the content of structural units (a-3) derived from vinyl monomers having acidic groups is 5 mol% or more, the dissolution rate when neutralized with alkali during alkaline development will be faster, and if it is 30 mol% or less, the hydrophilicity will not be too high, and the disorder of the formed pixels can be suppressed.

[0071] The A block may also preferably have structural units derived from at least one (meth)acrylic monomer selected from the group consisting of (meth)acrylic monomers having a linear alkyl group, (meth)acrylic monomers having a cyclic alkyl group, and (meth)acrylic monomers having an aryl group. In this case, the total content of structural units derived from at least one (meth)acrylic monomer selected from the group consisting of (meth)acrylic monomers having a linear alkyl group, (meth)acrylic monomers having a cyclic alkyl group, and (meth)acrylic monomers having an aryl group is preferably 25 mol% or more, more preferably 35 mol% or more, even more preferably 45 mol% or more, preferably 94 mol% or less, more preferably 90 mol% or less, and even more preferably 80 mol or less, out of 100 mol% of the structural units constituting the A block.

[0072] If the A block contains two or more structural units, the various structural units contained in the A block may be contained in the A block in any manner, such as random copolymerization or block copolymerization, and it is preferable that they be contained in a manner of random copolymerization from the viewpoint of uniformity. For example, the A block may be formed by a copolymer of structural units consisting of block a1 and structural units consisting of block a2.

[0073] (Block Copolymer) The structure of the block copolymer is preferably a linear block copolymer. The linear block copolymer may have any structure (arrangement), but from the viewpoint of the physical properties of the linear block copolymer or the physical properties of the composition, when block A is represented as A and block B as B, (A - B) m Type, (A-B) m - Type A, (B-A) mIt is preferable that the copolymer has at least one structure selected from the group consisting of -B type (where m is an integer of 1 or more, for example, an integer from 1 to 3). Among these, an A-B type diblock copolymer is preferred from the viewpoint of handling ease during processing and physical properties of the composition. It is believed that by forming an A-B type diblock copolymer, the structural units (b-1) and (b-2) of the B block are localized, and can efficiently and suitably interact with the colorant, dispersion medium, and binder resin. The block copolymer may have other blocks besides the A block and the B block.

[0074] In all structural units constituting the block copolymer, the content of the total number of moles of structural units constituting block A is preferably 30 mol% or more, more preferably 40 mol% or more, even more preferably 45 mol% or more, preferably 85 mol% or less, more preferably 70 mol% or less, even more preferably 60 mol% or less, and particularly preferably 55 mol% or less.

[0075] In all structural units constituting the block copolymer, the content of the total number of moles of structural units constituting block B is preferably 15 mol% or more, more preferably 30 mol% or more, even more preferably 40 mol% or more, particularly preferably 45 mol% or more, preferably 70 mol% or less, more preferably 60 mol% or less, and even more preferably 55 mol% or less.

[0076] In the block copolymer, the molar ratio (A block / B block) of the total molar amount of structural units constituting block A to the total molar amount of structural units constituting block B is preferably 0.4 or more, more preferably 0.6 or more, even more preferably 0.8 or more, preferably 6.0 or less, more preferably 4.0 or less, even more preferably 3.0 or less, and particularly preferably 1.5 or less. If the molar ratio (A block / B block) is 0.4 or more, viscosity stability is improved, and if it is 6.0 or less, dispersibility is improved.

[0077] The weight-average molecular weight (Mw) of the block copolymer is preferably 5,000 or more, more preferably 6,000 or more, even more preferably 7,000 or more, preferably 40,000 or less, more preferably 30,000 or less, and even more preferably 20,000 or less. If Mw is within the above range, the viscosity stability when used as a dispersant will be better. The molecular weight of the block copolymer is measured by gel permeation chromatography (hereinafter referred to as "GPC").

[0078] The molecular weight distribution (Mw / Mn) of the block copolymer is preferably 3.0 or less, more preferably 2.0 or less, and even more preferably 1.6 or less. A molecular weight distribution of 3.0 or less results in better dispersion performance when used as a dispersant. The molecular weight distribution is determined by (weight-average molecular weight of the block copolymer (Mw)) / (number-average molecular weight of the block copolymer (Mn)). A smaller molecular weight distribution value indicates a narrower molecular weight distribution and a copolymer with more uniform molecular weights, with the narrowest molecular weight distribution occurring when the value is 1.0. In other words, the lower limit of the molecular weight distribution is 1.0.

[0079] From the viewpoint of dispersibility, the amine value of the block copolymer is preferably 10 mg KOH / g or more, more preferably 30 mg KOH / g or more, even more preferably 50 mg KOH / g or more, preferably 170 mg KOH / g or less, more preferably 150 mg KOH / g or less, and even more preferably 130 mg KOH / g or less.

[0080] When the block copolymer contains structural units having acidic groups, the acid value of the block copolymer is preferably 10 mg KOH / g or more, preferably 50 mg KOH / g or less, more preferably 40 mg KOH / g or less, and even more preferably 35 mg KOH / g or less. By setting the acid value within this range, the block copolymer can act suitably with alkali-soluble resins without impairing its affinity for colorants.

[0081] (Method for producing block copolymers) Methods for producing the block copolymer include: first producing block A by polymerization reaction of vinyl monomer and polymerizing the monomer of block B onto block A; first producing block B and polymerizing the monomer of block A onto block B; and separately producing block A and block B, and then coupling block A and block B.

[0082] The polymerization method is not particularly limited, but living polymerization is preferred. That is, the block copolymer is preferably one polymerized by living polymerization. In living polymerization, among the four elementary reactions in chain polymerization (initiation, growth, termination, and chain transfer), side reactions such as termination and chain transfer reactions are substantially absent, and the vinyl monomer reacts and the polymer chain grows without deactivation of the reaction sites (polymerization growth ends). Therefore, it is easy to produce copolymers with a narrow molecular weight distribution and a uniform composition. Living polymerization includes living radical polymerization, living anionic polymerization, and living cationic polymerization. Among these, living radical polymerization is preferred from the viewpoint of ease of polymerization. Furthermore, living radical polymerization is preferred because it maintains the ease and versatility of conventional radical polymerization while allowing for precise control of the molecular weight distribution and easy production of copolymers with a uniform composition.

[0083] Living radical polymerization includes methods that utilize compounds capable of generating nitroxide radicals, depending on the method used to stabilize the polymerization growth ends (nitroxide method; NMP method); methods that use metal complexes such as copper and ruthenium, with halogenated compounds as polymerization initiators, and polymerize them in a living manner (ATRP method); methods that use dithiocarboxylic acid esters or xantate compounds (RAFT method); methods that use organotellurium compounds (TERP method); methods that use organiodine compounds (ITP method); and methods that use iodine compounds as polymerization initiators and organic compounds such as phosphorus compounds, nitrogen compounds, oxygen compounds, or hydrocarbons as catalysts (reversible transfer catalytic polymerization; RTCP method, reversible catalyst-mediated polymerization; RCMP method). Among these methods, the TERP method is preferred from the viewpoint of the diversity of monomers that can be used, molecular weight control in the polymer range, and uniform composition or coloration.

[0084] The TERP method is a method for polymerizing radical polymerizable compounds (vinyl monomers) using an organic tellurium compound as a chain transfer agent, and is described, for example, in International Publication Nos. 2004 / 14848, 2004 / 14962, 2004 / 072126, 2004 / 096870, and 2020 / 116144.

[0085] Specific polymerization methods of the TERP method include the following (a) to (d): (a) A method of polymerizing vinyl monomer using an organic tellurium compound represented by formula (T1). (b) A method of polymerizing vinyl monomer using a mixture of an organic tellurium compound represented by formula (T1) and an azo polymerization initiator. (c) A method of polymerizing vinyl monomer using a mixture of an organic tellurium compound represented by formula (T1) and an organic diterlide compound represented by formula (T2). (d) A method of polymerizing vinyl monomer using a mixture of an organic tellurium compound represented by formula (T1), an azo polymerization initiator, and an organic diterlide compound represented by formula (T2).

[0086] R t1 -Te-CR t2 R t3 R t4 (T1) Rt1 -Te-Te-R t1 (T2) [In equations (T1) and (T2), R t1 R represents an alkyl group, aryl group, or aromatic heterocyclic group having 1 to 8 carbon atoms. t2 and R t3 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. t4 This represents an alkyl group, aryl group, substituted aryl group, aromatic heterocyclic group, alkoxy group, acyl group, amide group, oxycarbonyl group, cyano group, allyl group, or propargyl group having 1 to 8 carbon atoms.

[0087] The organic tellurium compounds represented by formula (T1) include, specifically, ethyl = 2-methyl-2-n-butylteranyl propionate, ethyl = 2-n-butylteranyl propionate, (2-hydroxyethyl) = 2-methyl-methylteranyl propionate, and other organic tellurium compounds described in International Publication Nos. 2004 / 14848, 2004 / 14962, 2004 / 072126, 2004 / 096870, and 2020 / 116144.

[0088] Specific examples of the organic diterlide compound represented by formula (T2) include dimethyl diterlide and dibutyl diterlide. The azo polymerization initiator can be any azo polymerization initiator used in normal radical polymerization without particular restrictions, such as 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 1,1'-azobis(1-cyclohexanecarbonitride), dimethyl-2,2'-azobisisobutyrate, 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), and 2,2'-azobis(N-butyl-2-methylpropionamide).

[0089] The polymerization step involves mixing a vinyl monomer, an organic tellurium compound of formula (T1), and, depending on the type of vinyl monomer, an azo polymerization initiator and / or an organic diterlide compound of formula (T2) in a container purged with an inert gas. Examples of inert gases used include nitrogen, argon, and helium. Argon and nitrogen are preferred. The amount of vinyl monomer used in (a), (b), (c), and (d) above may be adjusted as appropriate depending on the desired properties of the copolymer.

[0090] The polymerization reaction can be carried out without a solvent, but it may also be carried out using an aprotic or protic solvent commonly used in radical polymerization, while stirring the mixture. Examples of usable aprotic solvents include acetonitrile, methyl ethyl ketone, anisole, benzene, toluene, propylene glycol monomethyl ether acetate, ethyl acetate, tetrahydrofuran, N,N-dimethylformamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, acetone, dioxane, chloroform, and carbon tetrachloride. Examples of protic solvents include water, methanol, ethanol, isopropanol, n-butanol, ethyl cellosolve, butyl cellosolve, 1-methoxy-2-propanol, hexafluoroisopropanol, and diacetone alcohol. The solvent may be used alone or in combination of two or more. The amount of solvent used can be adjusted as appropriate; for example, 0.01 ml to 50 ml per 1 g of vinyl monomer is preferred. In addition to the solvent, a surfactant and / or dispersant may also be used in the polymerization reaction. The reaction temperature and reaction time can be adjusted as appropriate depending on the molecular weight or molecular weight distribution of the copolymer obtained, but typically, stirring is carried out at 0°C to 150°C for 1 minute to 100 hours. At this time, the pressure is usually atmospheric pressure, but it may be increased or decreased. The polymerization reaction may also be carried out under light irradiation. After the polymerization reaction is complete, the target copolymer can be separated from the obtained reaction mixture by removing the solvent used, residual vinyl monomer, etc., using conventional separation and purification methods.

[0091] The growth ends of the copolymer obtained by the polymerization reaction are derived from the tellurium compound -TeR t1 (In the formula, R t1 The form is the same as described above, and although it is deactivated by handling in air after the polymerization reaction is complete, tellurium atoms may remain. Copolymers with tellurium atoms remaining at the ends may be discolored or have poor thermal stability, so it is preferable to remove the tellurium atoms. Methods for removing tellurium atoms include radical reduction methods; adsorption methods using activated carbon, etc.; and adsorption methods using ion exchange resins, etc. These methods can also be used in combination. The other end of the copolymer obtained by the polymerization reaction (the end opposite to the growth end) is -CR derived from the tellurium compound. t2 R t3 R t4 (In the formula, R t2 , R t3 and R t4 The form is the same as described above. Therefore, the copolymer obtained by the TERP method does not have substituents containing sulfur atoms at the terminals.

[0092] <Dispersant> The dispersant of the present invention contains the block copolymer as a main component (50% by mass or more). The content of the block copolymer in the dispersant is preferably 70% by mass or more, more preferably 90% by mass or more. The dispersant may consist only of the block copolymer.

[0093] The dispersant of the present invention facilitates the dispersion of colorants when prepared as a dispersant solution before the preparation of the colored composition. The solvent used in the dispersant solution is preferably one that can dissolve the dispersant, does not react with these components, and is moderately volatile. Examples of such solvents include the dispersion media used in the colored composition described later. The solvent content in the dispersant solution is not particularly limited and can be adjusted as appropriate. The upper limit of the solvent content in the dispersant solution is usually 99% by mass. The lower limit of the dispersion media content in the dispersant solution is usually 10% by mass, preferably 30% by mass, considering the viscosity suitable for the production of the colored composition described later.

[0094] The aforementioned block copolymer exhibits an effect of enhancing the dispersibility of colorants because block A has appropriate compatibility with the dispersion medium and block B has high adsorption to colorants. In other words, the dispersant of the present invention is a component that disperses colorants well through this effect, and therefore is not particularly limited to the type of colorant to be dispersed. The dispersant of the present invention is suitable for use as a dispersant for colorants in color filters because it is excellent not only in the dispersion performance of colorants but also in the alkali developability of the resulting colored composition. Furthermore, because the dispersant of the present invention has high dispersion performance of colorants, it can also be used in inkjet inks, printing inks, writing instrument inks, paints, etc. By appropriately changing the composition of the block copolymer, it can be used not only in colored compositions using organic solvents but also in colored compositions using aqueous solvents.

[0095] <Coloring Composition> The coloring composition of the present invention contains the dispersant, coloring agent and dispersion medium. The coloring composition of the present invention is suitable for use as a coloring composition for color filters because it has excellent dispersion performance of the coloring agent as well as alkaline developability.

[0096] (Coloring agent) The type of coloring agent can be appropriately selected according to its application and is not particularly limited. The colored composition preferably contains a pigment as a coloring agent. The pigment may be either an organic pigment or an inorganic pigment, but an organic pigment mainly composed of an organic compound is particularly preferred. Examples of pigments include red pigments, yellow pigments, orange pigments, blue pigments, green pigments, purple pigments, and other pigments of various colors. Examples of pigment structures include azo pigments such as monoazo pigments, diazo pigments, and condensed diazo pigments, diketopyrrolopyrrole pigments, phthalocyanine pigments, isoindolinone pigments, isoindoline pigments, quinacridone pigments, indigo pigments, thioindigo pigments, quinophthalone pigments, dioxazine pigments, anthraquinone pigments, perylene pigments, and perinone pigments, and other polycyclic pigments. Among these, phthalocyanine pigments have excellent heat resistance. The colored composition may contain only one type of pigment or multiple types.

[0097] Specific examples of pigments include red pigments such as C. I. Pigment Red 7, 9, 14, 41, 48:1, 48:2, 48:3, 48:4, 81:1, 81:2, 81:3, 122, 123, 146, 149, 168, 177, 178, 179, 187, 200, 202, 208, 210, 215, 224, 254, 255, 264, 291, etc.; C. I. Pigment Yellow: Yellow pigments such as 1, 3, 5, 6, 14, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 93, 97, 98, 104, 108, 110, 138, 139, 147, 150, 151, 154, 155, 166, 167, 168, 170, 180, 185, 188, 193, 194, 213, etc.; C.I. Pigment Orange: Orange pigments such as 36, 38, 43, etc.; C.I. Pigment Blue: Blue pigments such as 15, 15:2, 15:3, 15:4, 15:6, 16, 22, 60, etc.; C.I. Examples of green pigments include C.I. Pigment Green 7, 36, 58, 59, 62, 63, aluminum phthalocyanine, polyhalogenated aluminum phthalocyanine, aluminum phthalocyanine hydroxide, diphenoxyphosphinyloxyaluminum phthalocyanine, diphenylphosphinyloxyaluminum phthalocyanine, polyhalogenated diphenoxyphosphinyloxyaluminum phthalocyanine, and polyhalogenated diphenylphosphinyloxyaluminum phthalocyanine; purple pigments such as C.I. Pigment Violet 23, 32, 50, and preferably C.I. Pigment Red 177, 254, 255, 264, 291; C.I. Pigment Blue 15, 15:2, 15:3, 15:4, 15:6, 16; C.I. Pigment Green values ​​are 7, 36, 58, 59, 62, and 63.

[0098] When forming a light-shielding material such as a black matrix for a color filter using the colored composition of the present invention, a black pigment can be used as the coloring agent. The black pigment may be used alone, or it may be used in combination with the aforementioned red, green, blue, and other pigments. Examples of black pigments that can be used alone include carbon black, acetylene black, lamp black, bone black, graphite, iron black, and titanium black. Among these, carbon black and titanium black are preferred from the viewpoint of light-shielding rate and image characteristics.

[0099] Furthermore, the coloring agent may contain a pigment derivative as a dispersion aid. Preferably, the pigment derivative contains an acidic pigment derivative having an acidic group, in order to adsorb it by ionic bonding with the basic group in the block copolymer contained in the dispersant. This pigment derivative has an acidic group introduced into its pigment skeleton. The pigment skeleton is preferably the same or similar to the skeleton of the coloring agent constituting the coloring composition, or the same or similar to the compound that serves as the raw material for the coloring agent. Specific examples of pigment skeletons include azo pigment skeletons, phthalocyanine pigment skeletons, anthraquinone pigment skeletons, triazine pigment skeletons, acridine pigment skeletons, and perylene pigment skeletons. The acidic group introduced into the pigment skeleton is preferably a carboxyl group, a phosphate group, or a sulfonic acid group. A sulfonic acid group is preferred due to ease of synthesis and the strength of its acidity. The acidic group may be directly bonded to the pigment skeleton, or it may be bonded to the pigment skeleton via hydrocarbon groups such as alkyl groups or aryl groups; or via ester, ether, sulfonamide, or urethane bonds. There are no particular limitations on the amount of dye derivative used, but it is preferably 4 to 17 parts by mass per 100 parts by mass of coloring agent.

[0100] The particle size of the coloring agent can be appropriately selected according to its application and is not particularly limited. Preferably, from the viewpoint of high transparency and high contrast of the colored composition, the particle size of the coloring agent is 10 nm to 150 nm.

[0101] From the viewpoint of brightness, the content of the coloring agent in the colored composition is preferably 10% to 80% by mass, more preferably 20% to 70% by mass, and more preferably 30% to 60% by mass, relative to the total solid content of the colored composition. Here, the solid content refers to components other than the dispersion medium described later.

[0102] The amount of dispersant in the colored composition relative to the coloring agent is preferably 5 to 200 parts by mass, more preferably 10 to 100 parts by mass, and even more preferably 10 to 80 parts by mass, per 100 parts by mass of the coloring agent. The viscosity of the colored composition is good when the amount of dispersant is within the above range.

[0103] (Dispersion medium) The dispersion medium used in the present invention can be appropriately selected and used as long as it disperses or dissolves the other components constituting the colored composition, does not react with these components, and has moderate volatility. For example, conventionally known organic solvents can be used, such as glycol monoalkyl ethers, glycol dialkyl ethers, glycol alkyl ether acetates, alkyl acetates, ethers, ketones, monohydric or polyhydric alcohols, aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, linear or cyclic esters, halogenated hydrocarbons, ether ketones, nitriles, etc., and these can be used individually or in combination of two or more. From the viewpoint of dispersibility of colorants, solubility of dispersants, and coatability of the colored composition, one or more organic solvents selected from the group consisting of glycol alkyl ether acetates, glycol monoalkyl ethers, monohydric or polyhydric alcohols, and linear or cyclic esters can be used in combination.

[0104] Examples of the glycol alkyl ether acetates include 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. Examples of the glycol monoalkyl ethers include 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. Examples of the monohydric or polyhydric alcohols include ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol, propylene glycol, butanediol, diethylene glycol, dipropylene glycol, triethylene glycol, methoxypropanol, methoxymethyl pentanol, glycerin, and benzyl alcohol.Examples of the aforementioned chain-like or cyclic esters include 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.

[0105] Among organic solvents, glycol alkyl ether acetates are preferred because they offer a good balance of applicability and surface tension, and the solubility of the components in the colored composition is relatively high. Glycol alkyl ether acetates may be used alone or in combination with other organic solvents. It is also preferable to use organic solvents with a boiling point of 150°C or higher. By using organic solvents with a high boiling point, it is possible to suppress the destruction of the interrelationships of the colored composition due to rapid drying of the colored composition.

[0106] The boiling point of the organic solvent at atmospheric pressure (1013.25 hPa) is preferably 100°C to 220°C. If the coloring composition contains a large amount of organic solvent with a boiling point above 220°C, when the coating film applied to the coloring composition is pre-baked during the production of the color filter described later, the organic solvent may not evaporate sufficiently and may remain in the dried coating film, potentially reducing the heat resistance of the dried coating film. Furthermore, if the composition contains a large amount of organic solvent with a boiling point below 100°C, it becomes difficult to apply the coating uniformly without unevenness, potentially resulting in a coating film with excellent surface smoothness.

[0107] The content of the dispersion medium in the colored composition is not particularly limited and can be adjusted as appropriate. The upper limit of the dispersion medium content in the colored composition is usually 99% by mass. The lower limit of the dispersion medium content in the colored composition is usually 70% by mass, taking into consideration the viscosity suitable for coating the colored composition. The dispersion medium can be used as a solvent for dissolving and removing precipitates formed from the colored composition.

[0108] (Binder Resin) The colored composition of the present invention may contain a binder resin (except for the block copolymer of the present invention). Examples of binder resins include alkali-soluble resins, polymerizable compounds, thermosetting resins, thermoplastic resins, etc. These can be used individually or in combination of two or more. Among these, alkali-soluble resins and / or polymerizable compounds are preferred.

[0109] The binder resin content in the colored composition is preferably 1% to 70% by mass, and more preferably 5% to 50% by mass, based on the total amount of binder resin used and the total solid content of the colored composition.

[0110] (Alkali-soluble resin) The alkali-soluble resin is not particularly limited as long as it acts as a binder for the coloring agent and is soluble in the developing solution, preferably an alkaline developing solution, used in the developing process when manufacturing the color filter, but it is preferable that it is a polymer having acidic groups such as carboxyl groups and phenolic hydroxyl groups.

[0111] Examples of alkali-soluble resins include polymers having carboxyl groups; polymers obtained by adding an unsaturated monobasic acid to at least a portion of the epoxy groups of a copolymer of a vinyl monomer having epoxy groups and another vinyl monomer, or polymers obtained by adding a polybasic acid anhydride to at least a portion of the hydroxyl groups produced by the addition reaction. These can be used individually or in combination of two or more.

[0112] Polymers having carboxyl groups as alkali-soluble resins are not particularly limited as long as they have carboxyl groups, and are usually obtained by polymerizing vinyl monomers having carboxyl groups. Examples of vinyl monomers having carboxyl groups include (meth)acrylic acid, maleic acid, crotonic acid, itaconic acid, fumaric acid, 2-((meth)acryloyloxy)ethyl hydrogen succinate, 2-((meth)acryloyloxy)ethyl hydrogen hexahydrophthalate, 2-((meth)acryloyloxy)ethyl hydrogen phthalate, 2-carboxyethyl (meth)acrylic acid, and caprolactone adducts of (meth)acrylic acid, with (meth)acrylic acid being preferred.

[0113] Polymers having carboxyl groups as alkali-soluble resins include vinyl monomers having carboxyl groups, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, tricyclodecanyl (meth)acrylate, hydroxypropyl (meth)acrylate, glycerol mono(meth)acrylate, 2-hydroxyethyl (meth)acrylate, and 3-hydroxy (meth)acrylate. Roxypropyl, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, glycerol mono(meth)acrylate, glycidyl (meth)acrylate, (3,4-epoxycyclohexyl)methyl (meth)acrylate, styrene, α-methylstyrene, N-cyclohexylmaleimide, N-phenylmaleimide, N-benzylmaleimide, and other vinyl monomers without carboxyl groups may be copolymerized, and a copolymer of a vinyl monomer having a carboxyl group and another vinyl monomer without a carboxyl group is preferred. The polymerization method of these copolymers is not particularly limited, but living polymerization is preferred from the viewpoint of alkali solubility. Furthermore, these copolymers may be formed in any form, such as random copolymerization or block copolymerization, but random copolymerization is preferred.

[0114] Specific examples of polymers having carboxyl groups as alkali-soluble resins include copolymers of (meth)acrylic acid and butyl (meth)acrylate, copolymers of (meth)acrylic acid and benzyl (meth)acrylate, copolymers of (meth)acrylic acid, butyl (meth)acrylate and benzyl (meth)acrylate, copolymers of (meth)acrylic acid, styrene and α-methylstyrene, and copolymers of (meth)acrylic acid and cyclohexylmaleimide.

[0115] The polymer having a carboxyl group as an alkali-soluble resin preferably has a structural content derived from vinyl monomers having a carboxyl group of 5% to 90% by mass, more preferably 20% to 70% by mass. Furthermore, the structural unit content derived from (meth)acrylate in the polymer is preferably 70% by mass or more.

[0116] The alkali-soluble resin may have a radically polymerizable carbon-carbon double bond in its side chain. Having a double bond in the side chain enhances the photocurability of the colored composition according to the present invention, thereby further improving resolution and adhesion. As a method for introducing a radically polymerizable carbon-carbon double bond in the side chain, for example, a compound such as glycidyl (meth)acrylate, (3,4-epoxycyclohexyl)methyl (meth)acrylate, or o-(or m-, or p-) vinylbenzylglycidyl ether is reacted with the acidic group of the alkali-soluble resin.

[0117] If the Mw of the alkali-soluble resin is 3,000 or higher, the heat resistance and film strength of the colored layer formed from the colored composition will be good, and if it is 100,000 or lower, the alkali developability when the colored composition is used as the colored layer will be even better.

[0118] The acid value of the alkali-soluble resin is preferably 20 mg KOH / g to 170 mg KOH / g, more preferably 90 mg KOH / g to 150 mg KOH / g. When the acid value is 20 mg KOH / g or higher, the alkali developability when the colored composition is used as a colored layer is further improved, and when it is 170 mg KOH / g or lower, the heat resistance is improved.

[0119] In the colored composition, the content of alkali-soluble resin is preferably 5 to 200 parts by mass, more preferably 20 to 80 parts by mass, per 100 parts by mass of coloring material.

[0120] (Polymerizable Compounds) Examples of polymerizable compounds include polymerizable resins such as those obtained by introducing crosslinking groups such as (meth)acrylic compounds and cinnamic acid via isocyanate groups, aldehyde groups, epoxy groups, etc., to linear polymers having reactive substituents such as hydroxyl groups, carboxyl groups, and amino groups; compounds having one polymerizable unsaturated bond in the molecule, such as monofunctional (meth)acrylic monomers (alkyl (meth)acrylate, aralkyl (meth)acrylate, etc.); and compounds having two or more polymerizable unsaturated bonds in the molecule, such as polyfunctional (meth)acrylic monomers (di(meth)acrylate of dihydric alcohols, poly(meth)acrylate of trihydric or higher polyhydric alcohols, etc.). Examples of polymerizable unsaturated bonds include carbon-carbon double bonds and carbon-carbon triple bonds. These can be used individually or in combination of two or more. Among these, compounds having two or more polymerizable unsaturated bonds in the molecule are preferred.

[0121] Examples of monomers having two or more polymerizable unsaturated bonds in their molecule as polymerizable compounds include bisphenol di(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, glycerol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, trimethylolpropane tris(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and dipentaerythritol penta(meth)acrylate.

[0122] The polymerizable compound content in the coloring composition is preferably 10 to 1,000 parts by mass, more preferably 20 to 500 parts by mass, per 100 parts by mass of the coloring agent. If the polymerizable compound content is within the above range, sufficient curability and good alkali developability are obtained. An alkali-soluble resin and a polymerizable compound may be used in combination as the binder resin.

[0123] (Thermosetting resins, thermoplastic resins) Examples of thermosetting resins and thermoplastic resins include butyral resin, styrene-maleic acid copolymer, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyurethane resins, phenolic resins, polyester resins, (meth)acrylic resins, alkyd resins, styrene resins, polyamide resins, rubber resins, cyclocompound rubber, epoxy resins, celluloses, polybutadiene, polyimide resins, benzoguanamine resins, melamine resins, urea resins, etc.

[0124] (Photopolymerization initiator) The colored composition of the present invention may optionally contain a photopolymerization initiator. This can impart radiation sensitivity to the colored composition. A photopolymerization initiator is a compound that generates an active species capable of initiating polymerization of polymerizable compounds upon exposure to radiation such as visible light, ultraviolet light, far-infrared rays, electron beams, and X-rays.

[0125] Examples of photopolymerization initiators include thioxanthone compounds, acetophenone compounds, biimidazole compounds, triazine compounds, O-acyloxime compounds, onium salt compounds, benzoin compounds, benzophenone compounds, α-diketone compounds, polynuclear quinone compounds, diazo compounds, and imidosulfonate compounds. Photopolymerization initiators can be used individually or in combination of two or more.

[0126] The amount of photopolymerization initiator in the colored composition is preferably 0.01 to 120 parts by mass, more preferably 1 to 100 parts by mass, per 100 parts by mass of polymerizable compound. In this case, if the amount of photopolymerization initiator is too low, curing may be insufficient upon exposure, while if it is too high, the formed colored layer tends to detach easily from the substrate during development.

[0127] (Other Compounding Agents) In addition to the compounding agents mentioned above, other compounding agents may be added to the colored composition of the present invention, provided that they do not impair the desirable physical properties of the present invention. Examples of other compounding agents include dispersants other than the block copolymer of the present invention (urethane-based dispersants, polyethyleneimine-based dispersants, polyoxyethylene alkyl ether-based dispersants, polyoxyethylene glycol diester-based dispersants, sorbitan aliphatic ester-based dispersants, aliphatic-modified polyester-based dispersants, etc.), sensitizing dyes, thermal polymerization inhibitors, nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, plasticizers, organic carboxylic acid compounds, organic carboxylic acid anhydrides, antioxidants, ultraviolet absorbers, light stabilizers, pH adjusters, preservatives, fungicides, anti-aggregation agents, adhesion improvers, developer improvers, and storage stabilizers.

[0128] Examples of sensitizing dyes include 4,4'-dimethylaminobenzophenone, 4,4'-diethylaminobenzophenone, 2-aminobenzophenone, 4-aminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 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, and 2,5-bis(p-diethylaminophenyl)1,3,4- Examples include oxazole, 2-(p-dimethylaminophenyl)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, (p-diethylaminophenyl)pyrimidine, etc.

[0129] Examples of thermal polymerization inhibitors include hydroquinone, p-methoxyphenol, pyrogallol, catechol, 2,6-t-butyl-p-cresol, and β-naphthol.

[0130] Nonionic surfactants include 1,1,2,2-tetrafluorooctyl(1,1,2,2-tetrafluoropropyl) ether, 1,1,2,2-tetrafluorooctylhexyl ether, octaethylene glycol di(1,1,2,2-tetrafluorobutyl) ether, hexaethylene glycol di(1,1,2,2,3,3-hexafluoropentyl) ether, octapropylene glycol di(1,1,2,2-tetrafluorobutyl) ether, hexapropylene glycol di(1,1,2,2,3,3-hexafluoropentyl) ether, sodium perfluorododecylsulfonate, 1,1,2,2,8,8,9,9,10,10-decafluorododecane, and 1,1,2,2,3,3-hexafluoro Examples of polyoxyethylene surfactants include fluorinated surfactants such as can; silicone surfactants; polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl esters, polyoxyethylene fatty acid esters, glycerin fatty acid esters, polyoxyethylene glycerin fatty acid esters, pentaerythritol fatty acid esters, polyoxyethylene pentaerythritol fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, sorbitol fatty acid esters, and polyoxyethylene sorbitol fatty acid esters. Examples of anionic surfactants include alkyl sulfonates, alkylbenzene sulfonates, alkylnaphthalene sulfonates, polyoxyethylene alkyl ether sulfonates, alkyl sulfates, alkyl sulfate esters, higher alcohol sulfate esters, aliphatic alcohol sulfate esters, polyoxyethylene alkyl ether sulfates, polyoxyethylene alkylphenyl ether sulfates, alkyl phosphate esters, polyoxyethylene alkyl ether phosphates, polyoxyethylene alkylphenyl ether phosphates, and special polymer surfactants. Cationic surfactants include quaternary ammonium salts, imidazoline derivatives, and alkylamine salts.Examples of amphoteric surfactants include betaine-type compounds, imidazolium salts, imidazolines, and amino acids.

[0131] Examples of plasticizers include dioctyl phthalate, didodecyl phthalate, triethylene glycol dicaprylate, dimethyl glycol phthalate, tricresyl phosphate, dioctyl adipate, dibutyl sebacate, and triacetylglycerin.

[0132] Examples of organic carboxylic acid compounds include aliphatic monocarboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid, pivalic acid, caproic acid, glycolic acid, acrylic acid, and methacrylic acid; aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, cyclohexanedicarboxylic acid, cyclohexenedicarboxylic acid, itaconic acid, citraconic acid, maleic acid, and fumaric acid; aliphatic tricarboxylic acids such as tricarbaryl acid and aconitic acid; aromatic carboxylic acids in which a carboxyl group is directly bonded to a phenyl group, such as benzoic acid, phthalic acid, trimesic acid, pyropetic acid, and merophanic acid; and aromatic carboxylic acids in which a carboxyl group is bonded to a phenyl group via a carbon bond, such as phenylacetic acid, hydroatropic acid, hydrocinnamic acid, phenylsuccinic acid, and cinnamilindenic acid. The inclusion of organic carboxylic acid compounds can improve alkali developability and soil staining. Examples of organic carboxylic acid anhydrides include acetic anhydride, trichloroacetic anhydride, trifluoroacetic anhydride, tetrahydrophthalic anhydride, succinic anhydride, maleic anhydride, citraconic anhydride, itaconic anhydride, glutaric anhydride, 1,2-cyclohexenedicarboxylic anhydride, n-octadecylsuccinic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and naphthalic anhydride. The inclusion of organic carboxylic acid anhydrides can improve alkali developability and reduce soil staining.

[0133] <Method for Producing Colored Compositions> Colored compositions can be prepared by mixing a colorant, a dispersant (or dispersant solution), a dispersion medium, and, if necessary, a binder resin, a photopolymerization initiator, and other compounding agents. Mixing can be done using, for example, a paint shaker, bead mill, ball mill, dissolver, or kneader. It is preferable to filter the colored composition after mixing. If the colored composition is alkaline developable, it can be suitably used as a color filter. As the alkaline developer, an aqueous solution containing an organic solvent or surfactant and an alkaline compound such as potassium hydroxide, sodium bicarbonate, sodium carbonate, or tetramethylammonium hydroxide can be used.

[0134] <Color Filter> The color filter of the present invention comprises a colored layer formed using the coloring composition described above.

[0135] One example of a method for manufacturing a color filter is as follows: First, a coloring composition in which red pigment is dispersed is applied to a transparent substrate such as a thermoplastic resin sheet (e.g., polyester resin, polyolefin resin, polycarbonate resin, polymethyl methacrylate resin), a thermosetting resin sheet (e.g., epoxy resin, unsaturated polyester resin, poly(meth)acrylic resin), or various types of glass. Then, pre-baking is performed to evaporate the solvent and form a coating film. Next, this coating film is exposed to light through a photomask, and then developed using an alkaline developer (an aqueous solution containing an organic solvent or surfactant and an alkaline compound such as potassium hydroxide, sodium bicarbonate, sodium carbonate, or tetramethylammonium hydroxide) to dissolve and remove the unexposed parts of the coating film. Subsequently, post-baking is performed to form a pixel array in which red pixel patterns are arranged in a predetermined sequence. Next, using a green coloring composition or a blue coloring composition, the same procedure as above is followed to apply, pre-bak, expose, develop, and post-bake each coloring composition to sequentially form a green pixel array and a blue pixel array on the same substrate. This results in a color filter in which pixel arrays of the three primary colors, red, green, and blue, are arranged on a substrate. However, in this invention, the order in which the pixels of each color are formed is not limited to the above. Furthermore, a black matrix may be provided on the transparent substrate used to form the pixel arrays of the three primary colors, red, green, and blue.

[0136] When applying the colored composition to the substrate, an appropriate coating method such as spray coating, roll coating, spin coating, slit die coating, or bar coating can be used, but spin coating or slit die coating is particularly preferred. After forming a protective film on the pixel pattern obtained in this way, a transparent conductive film (such as ITO) is formed by sputtering. After forming the transparent conductive film, a spacer can be further formed to create a color filter.

[0137] The color filter of the present invention has high brightness and dimensional accuracy, and can be suitably used in color liquid crystal display elements, color image tube elements, color sensors, organic EL display elements, electronic paper, and the like.

[0138] The present invention will be described in more detail below based on specific examples. The present invention is not limited in any way to the following examples, and can be implemented with appropriate modifications without changing its essence. The polymerization rate, weight-average molecular weight, molecular weight distribution, amine value and acid value of the block copolymer, the viscosity and yield value of the colored composition, and the properties of the coating film were evaluated according to the method described below.

[0139] The meanings of the abbreviations are as follows: BTEE: Ethyl 2-methyl-2-n-butylteranyl propionate DBDT: Dibutyl diterlide AIBN: 2,2'-azobis(isobutyronitrile) MMA: Methyl methacrylate BMA: n-butyl methacrylate EHMA: 2-ethylhexyl methacrylate BzMA: Benzyl methacrylate CL4MA: 4-mol caprolactone adduct of 2-hydroxyethyl methacrylate HEMA: 2-hydroxyethyl methacrylate M4EGMA: Polyethylene glycol (degree of polymerization = 4) methyl ether methacrylate MAA: Methacrylic acid MOEBDA: 2-methacryloyloxyethyl hydrogen phthalate DMAEMA: Dimethylaminoethyl methacrylate AN: Acrylonitrile MAN: Methacrylonitrile 4-CS: 4-cyanostyrene PMA: Propylene glycol monomethyl ether acetate

[0140] [Evaluation Method] (Polymerization Rate) Using a nuclear magnetic resonance (NMR) measuring device (Bruker BioSpin, Model: AVANCE500 (Frequency 500 MHz)), 1 ¹H-NMR was measured (solvent: CDCl3, internal standard: tetramethylsilane). The integral ratio of monomer-derived peaks and polymer-derived peaks was determined from the obtained NMR spectrum to calculate the monomer polymerization rate.

[0141] (Weight-average molecular weight and molecular weight distribution) These were determined by gel permeation chromatography (GPC) using a high-performance liquid chromatograph (Tosoh, model HLC-8320). One SHODEX KF-603 column (Φ6.0 mm × 150 mm) (SHODEX) was used, lithium bromide (30 mmol / L)-acetic acid (30 mmol / L)-N-methylpyrrolidone was used as the mobile phase, and a differential refractive index detector was used. The measurement conditions were a column temperature of 40°C, a sample concentration of 20 mg / mL, a sample injection volume of 10 μL, and a flow rate of 0.2 mL / min. Calibration curves were created using polystyrene (molecular weights 70,500, 37,900, 19,920, 10,200, 4,910, 2,630, 1,150) as standard substances, and the weight-average molecular weight (Mw) and number-average molecular weight (Mn) were measured. The molecular weight distribution (Mw / Mn) was calculated from these measurements.

[0142] (Amine Value) The amine value represents the mass of the basic component and the equivalent amount of potassium hydroxide per gram of solid content. The sample was dissolved in tetrahydrofuran, and the resulting solution was titrated with hydrochloric acid (0.1 mol / L)-propanol solution using a potentiometric titrator (product name: GT-06, manufactured by Nitto Seikou Analytech). The amine value (B) was calculated using the following formula, with the inflection point of the titration pH curve as the titration endpoint: B = 56.11 × Vs × 0.1 × f / w B: Amine value (mgKOH / g) Vs: Amount of hydrochloric acid (0.1 mol / L)-propanol solution used for titration (mL) f: Titer of hydrochloric acid (0.1 mol / L) (propanol) w: Mass of the sample (g) (converted to solid content)

[0143] (Acid Value) The acid value represents the mass of potassium hydroxide required to neutralize the acidic component per gram of solid content. The sample was dissolved in tetrahydrofuran, and a few drops of 1.0 w / v% phenolphthalein ethanol (90) solution were added to the resulting solution as an indicator. The solution was then titrated with potassium hydroxide (0.1 mol / L)-ethanol solution. The titration endpoint was defined as the point where a slight reddish tint remained, and the acid value was calculated using the following formula: A = 56.11 × Vs × 0.1 × f / w A: Acid value (mgKOH / g) Vs: Amount of potassium hydroxide (0.1 mol / L)-ethanol solution used for titration (mL) f: Titer of potassium hydroxide (0.1 mol / L)-ethanol solution w: Mass of the sample (g) (converted to solid content)

[0144] (Viscosity) Viscosity (mPa·s) was measured using an E-type viscometer (product name: RE-80L, manufactured by Toki Sangyo Co., Ltd.) with a cone rotor (0.8° × R24) at 25°C and a rotor rotation speed of 60 rpm. Measurements were taken for the initial viscosity immediately after preparation of the colored composition and the viscosity after storage of the prepared colored composition at 40°C for one week. Furthermore, if the viscosity was too high to be measured under the above measurement conditions (rotation speed, temperature, etc.), it was indicated as "high viscosity".

[0145] (Yield Value) Using an E-type viscometer (product name: RE-80L, manufactured by Toki Sangyo Co., Ltd.), the viscosity (mPa·s) was measured at 25°C with a cone rotor (0.8° × R24) and the rotor speed was varied. The yield value was calculated using Casson's formula. Measurements were taken for the initial yield value immediately after preparation of the colored composition and the yield value after storage of the prepared colored composition at 40°C for one week.

[0146] (Alkaline Developability) A coating film of the colored composition was formed on a glass plate (50 mm x 50 mm) with a cleaned surface using a spin coater (product name: MS-A100, manufactured by Mikasa) at 500 rpm for 5 seconds, and dried at 100°C for 5 minutes. Next, the glass plate with the coated film was immersed in 10 mL of alkaline developer and left at 23°C for 30 minutes to observe its solubility. For colored compositions 1-4 and 7-9, 0.1% tetramethylammonium hydroxide (TMAH) was used as the alkaline developer, and for colored compositions 5, 6 and 11, a 0.5% TMAH aqueous solution was used. Solubility was assessed by analyzing the absorbance at a wavelength of 663 nm for the green colored composition and at a wavelength of 555 nm for the red colored composition using an ultraviolet-visible spectrophotometer (product name: Spectrophotometer U-3900, Hitachi) and a quartz cell (10 × 10 × 40 mm) in an alkaline developer solution in which at least a portion of the coated film was dissolved. When the type and content of pigment in the colored composition are the same, and the alkaline developer used is the same, a higher absorbance indicates higher alkali developability of the coated film.

[0147] (Heat Resistance) A diluted solution of the colored composition, adjusted to a solid content concentration of 14.6% by mass, was applied to a glass substrate using a spin coater (product name: MS-150A, manufactured by Mikasa) at 500 rpm for 10 seconds. After pre-baking at 100°C for 5 minutes, the main bake was performed at 230°C for 30 minutes and dried to form a colored layer. After pre-baking and main baking, the colored layer surface was measured using a spectrophotometer (manufactured by Konica Minolta Japan, model "CM-5") to remove specular reflection and determine the b ＊ The values ​​were measured, and the difference between them was calculated. A smaller difference indicates better heat resistance.

[0148] <Synthesis of Block Copolymer> (Block Copolymer No. 1) In a flask equipped with a nitrogen inlet tube and a stirrer, 14.2 g of MMA, 73.3 g of BMA, 4.7 g of EHMA, 3.9 g of BzMA, 72.0 g of CL4MA, 10.9 g of MAA, 0.4 g of AIBN, and 147 g of PMA were charged. After purging with nitrogen, 7.5 g of BTEE and 9.2 g of DBDT were added, and the mixture was reacted at 60°C for 17 hours to polymerize Block A. The polymerization rate was 100%.

[0149] A mixed solution of 81.9 g of DMAEMA, 13.8 g of AN, and 80.5 g of PMA, which had been pre-purged with nitrogen, was added to the reaction solution, and the reaction was carried out at 60°C for 72 hours to polymerize block B. The polymerization rate was 90%.

[0150] After the reaction was complete, the reaction solution was poured into a stirred n-heptane. The precipitated polymer was filtered by suction and dried to obtain block copolymer No. 1. The obtained block copolymer No. 1 had an Mw of 13,060, an Mw / Mn of 1.60, an amine value of 102 mgKOH / g, and an acid value of 28 mgKOH / g.

[0151] (Block Copolymers No. 2-12) Block copolymers No. 2-12 were prepared in the same manner as block copolymer No. 1. Table 1 shows the monomers, polymerization agents, solvents, reaction conditions, and polymerization rates used. Table 2 shows the composition, Mw, Mw / Mn, amine value, and acid value of each block copolymer. The content of each structural unit in the copolymer was calculated from the charge ratio and polymerization rate of the monomers used in the polymerization reaction.

[0152]

[0153]

[0154] <Synthesis of Alkali-Soluble Resin> 40.0 g of MAA, 160.0 g of BzMA, and 580.0 g of PMA were charged into a flask equipped with an argon gas inlet tube and a stirrer. After purging with argon, 4.0 g of AIBN, 6.0 g of n-dodecanethiol, and 20.0 g of PMA were added and the mixture was heated to 90°C. While maintaining the solution at 90°C, 80.0 g of MAA, 320.0 g of BzMA, 8.0 g of AIBN, 12.0 g of n-dodecanethiol, and 50.0 g of PMA were added dropwise over 1.5 hours. Sixty minutes after the dropwise addition was complete, the temperature was raised to 110°C, and 0.8 g of AIBN and 10.0 g of PMA were added and reacted for 1 hour. Then, another 0.8 g of AIBN and 10.0 g of PMA were added and reacted for 1 hour. Finally, another 0.8 g of AIBN and 10.0 g of PMA were added and reacted for 1 hour.

[0155] The resulting reaction solution was cooled to room temperature, and 240.0 g of PMA was added to obtain an alkali-soluble resin solution with a non-volatile content of 39.5%. The Mw of the alkali-soluble resin was 9,150, the Mw / Mn ratio was 1.92, and the acid value was 128 mg KOH / g.

[0156] (Colored Compositions No. 1-6) Colored compositions were prepared using block copolymers No. 1-6 obtained above. Specifically, 0.8 g of block copolymer, 2.0 g of coloring agent (G58: C.I. Pigment Green 58, trade name: FASTOGEN® GREEN A310, manufactured by DIC), 0.8 g of alkali-soluble resin, and 21.1 g of PMA were added to a bead mill (trade name: DISPERMAT CA, manufactured by VMA-GETZMANN GmbH), and 100 g of zirconia beads (φ0.3 mm) were added, and the mixture was stirred for 3 hours. After stirring, the beads were filtered off to prepare colored compositions No. 1-6. The evaluation results are shown in Table 3.

[0157]

[0158] (Colored Compositions No. 7-12) Colored compositions were prepared using block copolymers No. 7-12 obtained above. Specifically, 0.8 g of block copolymer, 2.0 g of coloring agent (R254: C.I. Pigment Red 254, trade name: Irgafor Red BKCF, manufactured by Ciba Specialty Chemicals), 0.8 g of alkali-soluble resin, and 21.1 g of PMA were added to a bead mill (trade name: DISPERMAT CA, manufactured by VMA-GETZMANN GmbH), and 100 g of zirconia beads (φ0.3 mm) were added, and the mixture was stirred for 3 hours. After stirring, the beads were filtered off to prepare colored compositions No. 7-12. The evaluation results are shown in Table 4.

[0159]

[0160] Block copolymers No. 1-3, 5, 7-9, and 11 are characterized in that Block A does not contain structural units having a cyano group (b-1) or structural units having a basic group (b-2), while Block B contains structural units having a cyano group (b-1) and structural units having a basic group (b-2), with the content of structural unit (b-1) in 100 mol% of the structural units constituting Block B being 1 mol% to 50 mol%, and the molar ratio ((b-1) / (b-2)) of structural unit (b-1) to structural unit (b-2) in Block B being 0.01 to 1.0. Colored compositions No. 1-3, 5, 7-9, and 11, using these block copolymers No. 1-3, 5, 7-9, and 11 as dispersants, all exhibited high dispersion performance and improved alkali developability.

[0161] Block copolymers No. 4, 6, 10, and 12 are cases where Block A does not contain structural units having a cyano group (b-1) or a basic group (b-2), and Block B contains structural units having a basic group (b-2) but does not contain structural units having a cyano group (b-1). Colored compositions No. 4, 6, 10, and 12, which used these block copolymers as dispersants, exhibited poor dispersion performance.

[0162] The present invention includes the following embodiments.

[0163] (Aspect 1) A block copolymer having block A and block B, wherein block A substantially does not contain structural units having a cyano group (b-1) and structural units having a basic group (b-2), block B contains structural units having a cyano group (b-1) and structural units having a basic group (b-2), the content of structural unit (b-1) in 100 mol% of structural units constituting block B is 1 mol% to 50 mol%, and the molar ratio of structural unit (b-1) to structural unit (b-2) in block B ((b-1) / (b-2)) is 0.01 to 1.0.

[0164] (Aspect 2) The block copolymer according to Aspect 1, wherein the amine value of the block copolymer is 10 mgKOH / g to 170 mgKOH / g.

[0165] (Aspect 3) The block copolymer according to Aspect 1 or 2, wherein the structural unit (b-1) is a structural unit represented by formula (1), and the structural unit (b-2) is a structural unit represented by formula (2).

[0166] [In formula (1), R 11 represents a hydrogen atom or a methyl group. A 11 represents a single bond or a divalent linking group. ]

[0167] [In formula (2), R 21 represents a hydrogen atom or a methyl group. A 21 represents a single bond or a divalent linking group. R 22 and R 23 each independently represent a hydrocarbon group which may contain a heteroatom. R 22 and R 23 may be bonded to each other to form a cyclic structure. ]

[0168] (Aspect 4) The block copolymer according to any one of Aspects 1 to 3, wherein the A block contains at least one structural unit selected from the group consisting of a structural unit (a-1) derived from a (meth)acrylate having a hydroxy group and a structural unit (a-2) derived from a (meth)acrylate having an alkoxy group.

[0169] (Aspect 5) The block copolymer according to Aspect 4, wherein the total content ratio of the structural unit (a-1) derived from the (meth)acrylate having a hydroxy group and the structural unit (a-2) derived from the (meth)acrylate having an alkoxy group in 100 mol% of the structural units constituting the A block is 1 mol% to 70 mol%.

[0170] (Aspect 6) The block copolymer according to any one of aspects 1 to 5, wherein the molar ratio (A block / B block) of the total molar amount of structural units constituting block A to the total molar amount of structural units constituting block B is 0.4 to 6.0.

[0171] (Aspect 7) The block copolymer according to any one of aspects 1 to 6, wherein the weight-average molecular weight of the block copolymer is 5,000 to 40,000.

[0172] (Aspect 8) The block copolymer according to any one of aspects 1 to 7, wherein the block copolymer is obtained by living polymerization and has a molecular weight distribution (Mw / Mn) of 3.0 or less.

[0173] (Aspect 9) A dispersant characterized by containing a block copolymer according to any one of aspects 1 to 8.

[0174] (Aspect 10) A colored composition characterized by containing a coloring agent, a dispersion medium, and the dispersant described in Aspect 9.

[0175] (Aspect 11) The coloring composition according to aspect 10, for use in color filters.

[0176] (Aspect 12) A color filter characterized by comprising a colored layer formed using the colored composition described in Aspect 11.

Claims

1. A block copolymer comprising Block A and Block B, wherein Block A substantially does not contain structural units having a cyano group (b-1) and structural units having a basic group (b-2), Block B contains structural units having a cyano group (b-1) and structural units having a basic group (b-2), the content of structural unit (b-1) in 100 mol% of the structural units constituting Block B is 1 mol% to 50 mol%, and the molar ratio ((b-1) / (b-2)) of structural unit (b-1) to structural unit (b-2) in Block B is 0.01 to 1.

0.

2. The block copolymer according to claim 1, wherein the amine value of the block copolymer is 10 mg KOH / g to 170 mg KOH / g.

3. The block copolymer according to claim 1 or 2, wherein the structural unit (b-1) is a structural unit represented by formula (1), and the structural unit (b-2) is a structural unit represented by formula (2). [In equation (1), R 11 represents a hydrogen atom or a methyl group. A 11 This represents a single bond or a divalent linking group. [In equation (2), R 21 represents a hydrogen atom or a methyl group. A 21 R represents a single bond or a divalent linking group. 22 and R 23 Each of these independently represents a hydrocarbon group that may contain heteroatoms. 22 and R 23 These may be joined to each other to form a ring structure.

4. The block copolymer according to claim 1 or 2, wherein block A contains at least one structural unit selected from the group consisting of structural units (a-1) derived from a (meth)acrylate having a hydroxyl group and structural units (a-2) derived from a (meth)acrylate having an alkoxy group.

5. The block copolymer according to claim 4, wherein the total content of structural units (a-1) having a hydroxyl group and structural units (a-2) having an alkoxy group, in 100 mol% of the structural units constituting block A, is 1 mol% to 70 mol%.

6. The block copolymer according to claim 1 or 2, wherein the molar ratio (Block A / Block B) of the total molar amount of structural units constituting Block A to the total molar amount of structural units constituting Block B is 0.4 to 6.

0.

7. The block copolymer according to claim 1 or 2, wherein the weight-average molecular weight of the block copolymer is 5,000 to 40,000.

8. The block copolymer according to claim 1 or 2, wherein the block copolymer is obtained by living polymerization and has a molecular weight distribution (Mw / Mn) of 3.0 or less.

9. A dispersant characterized by containing the block copolymer described in claim 1 or 2.

10. A colored composition characterized by containing a coloring agent, a dispersion medium, and the dispersant described in claim 9.

11. The coloring composition according to claim 10, which is for use as a color filter.

12. A color filter characterized by comprising a colored layer formed using the colored composition described in claim 11.

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