JP7299895B2 - Dispersant composition, coloring composition, and color filter - Google Patents

Description

The present invention relates to dispersant compositions containing polymers.

2. Description of the Related Art Conventionally, dyeing, printing, inkjet, electrodeposition, pigment dispersion, and the like are known as methods of applying colorants to substrates in the production of color filters used in liquid crystal displays and the like. Among these, the pigment dispersion method is the mainstream from the viewpoint of spectral characteristics, durability, pattern shape and accuracy. In this pigment dispersion method, a coating film made of a coloring composition mixed with a pigment, a dispersant, a dispersion medium (solvent), a binder resin, etc. is formed on a substrate, and radiation is applied through a photomask having a desired pattern shape. It is cured by irradiation and alkali development is carried out.

In recent years, in order to obtain good color reproducibility and high contrast of color filters, increasing the concentration of pigments in coloring compositions has been studied. When the concentration of the pigment is increased, the proportion of the dispersant is relatively decreased, so the dispersant is required to have high dispersibility (see, for example, Patent Document 1 (paragraph 0004)). Further, in alkali development, binder resins having alkali solubility play a major role. However, in the case of a pigment dispersion composition with a high concentration of pigment, the proportion of the binder resin, which is a developing component, is reduced, resulting in poor alkali developability. Therefore, the dispersant is also required to have alkali developability, which is originally required for the binder resin. As such a dispersant, in Patent Document 2, an AB block copolymer consisting of an A block having a polylactone chain in the side chain and a B block having a tertiary amino group in the side chain is used as a pigment dispersion. (See Patent Document 2 (paragraphs 0023 to 0045)).

JP 2009-265515 A JP 2013-119568 A

It has been proposed to introduce a tertiary amino group into the side chain of a resin-type dispersant in order to improve the dispersibility of the colorant (see Patent Document 2). However, resin-type dispersants having tertiary amino groups are thought to generate formaldehyde over time due to the tertiary amino groups. Therefore, when such a resin-type dispersant is used in a coloring composition, formaldehyde is contained in the coloring composition. Since environmental standards have become stricter in recent years, the use of conventional resin-type dispersants causes the amount of formaldehyde in the coloring composition to fail to meet environmental standards.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a dispersant composition that generates a small amount of formaldehyde over time.

The dispersant composition of the present invention, which has solved the above problems, is characterized by containing a polymer having a structural unit represented by general formula (1).

［一般式（１）において、Ｒ¹¹は水素原子または置換基を有していてもよい鎖状もしくは環状の炭化水素基を表す。Ｒ¹²は置換基を有していてもよい鎖状もしくは環状の炭化水素基を表す。Ｒ¹¹およびＲ¹²が互いに結合して環状構造を形成していてもよい。Ｒ¹³は水素原子またはメチル基を表す。］

[In general formula (1), R ¹¹ represents a hydrogen atom or a chain or cyclic hydrocarbon group which may have a substituent. R ¹² represents a chain or cyclic hydrocarbon group which may have a substituent. R ¹¹ and R ¹² may combine with each other to form a cyclic structure. ^R13 represents a hydrogen atom or a methyl group. ]

When a polymer having an amino group is used as a dispersant, it is believed that formaldehyde is generated over time due to the amino group. Surprisingly, in the present invention, the structural unit having an amino group is a structural unit represented by general formula (1) that does not have an amino group. formaldehyde generation can be suppressed, and formaldehyde in the dispersant composition can be reduced.

The present invention also includes a coloring composition characterized by containing the dispersant composition, a coloring material, a binder resin and a dispersion medium. The present invention also includes a color filter comprising a colored layer formed using the coloring composition.

According to the present invention, a dispersant composition that generates a small amount of formaldehyde over time can be obtained.

An example of a preferred embodiment of the present invention will be described below. However, the following embodiments are merely examples. It is not limited to the following embodiments.

In the present invention, "(meth)acrylic" means "at least one of acrylic and methacrylic". "(Meth)acrylic monomer" refers to a monomer having a "(meth)acryloyl group" in the molecule. "(Meth)acryloyl" means "at least one of acryloyl and methacryloyl". A "vinyl monomer" refers to a monomer having a radically polymerizable carbon-carbon double bond in the molecule. A “structural unit derived from a (meth)acrylic monomer” refers to a structural unit in which a radically polymerizable carbon-carbon double bond of a (meth)acrylic monomer is polymerized to form a carbon-carbon single bond. A “structural unit derived from a vinyl monomer” refers to a structural unit in which a radically polymerizable carbon-carbon double bond of a vinyl monomer is polymerized to form a carbon-carbon single bond.

<Dispersant composition>
The dispersant composition of the present invention is characterized by containing a polymer having a structural unit represented by general formula (1) as a dispersant component.

When a polymer having an amino group is used as a dispersant, it is believed that formaldehyde is generated over time due to the amino group. Surprisingly, in the present invention, the structural unit having an amino group is a structural unit represented by general formula (1) that does not have an amino group. formaldehyde generation can be suppressed, and formaldehyde in the dispersant composition can be reduced.

A (meth)acrylic polymer can be mentioned as a polymer having a structural unit represented by the general formula (1).

From the viewpoint of reducing the amount of formaldehyde generated over time, the polymer having the structural unit represented by general formula (1) preferably does not have an amino group. In other words, it is preferable that the vinyl monomer constituting the polymer does not contain a vinyl monomer having an amino group. The content of structural units derived from a vinyl monomer having an amino group in the polymer (including those in which the amino group is quaternized) is preferably 2% by mass or less, more preferably 1% by mass or less. More preferably 0.1% by mass or less, most preferably 0% by mass. Also, the amine value of the polymer is preferably less than 10 mgKOH/g, more preferably less than 5 mgKOH/g, still more preferably less than 3 mgKOH/g, and most preferably 0 mgKOH/g.

The molecular weight of the polymer having the structural unit represented by general formula (1) is measured by gel permeation chromatography. The weight average molecular weight (Mw) of the polymer is preferably 3,000 or more, more preferably 4,000 or more, still more preferably 5,000 or more, and particularly preferably 6,000 or more and 40,000 or less. is preferably 30,000 or less, still more preferably 25,000 or less, and particularly preferably 20,000 or less. If the weight-average molecular weight is within the above range, the dispersion performance when used as a dispersant will be better.

(Block copolymer)
From the viewpoint of dispersibility, the polymer preferably has an A block having a structural unit derived from a (meth)acrylic monomer and a block copolymer having a B block having a structural unit represented by general formula (1). coalescence is preferred. Various constituent components of the block copolymer will be described below.

(A block)
The A block is a polymer block containing structural units derived from (meth)acrylic monomers. Structural units derived from (meth)acrylic monomers in the A block may be of only one type, or may be of two or more types. By having a structural unit derived from a (meth)acrylic monomer, it is possible to maintain high affinity with a dispersion medium (solvent) and a binder resin blended in a coloring composition.

The content of structural units derived from the (meth)acrylic monomer is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, particularly preferably 95% by mass or more, based on 100% by mass of the A block. is 100% by mass.

The (meth)acrylic monomers include (meth)acrylates having a chain alkyl group (straight-chain alkyl group or branched-chain alkyl group), (meth)acrylates having a cyclic alkyl group, and (meth)acrylates having a polycyclic structure. , (meth)acrylates having an aromatic group, (meth)acrylates having a polyalkylene glycol structural unit, (meth)acrylates having a hydroxy group, (meth)acrylates having a lactone-modified hydroxy group, (meth)acrylates having an alkoxy group Examples include acrylates, (meth)acrylates having an oxygen-containing heterocyclic group, (meth)acrylates having an acidic group, (meth)acrylic acid, and the like, and one or more of these may be used in combination. can be done.

As the (meth)acrylate having a straight-chain alkyl group, a (meth)acrylate having a straight-chain alkyl group having 1 to 20 carbon atoms in the straight-chain alkyl group is preferable, and the straight-chain alkyl group has 1 to 20 carbon atoms. A (meth)acrylate having a linear alkyl group of 10 is more preferred. Examples of (meth)acrylates having a linear alkyl group include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, decyl (meth)acrylate, n-lauryl (meth)acrylate, n-stearyl (meth)acrylate and the like.

The (meth)acrylate having a branched chain alkyl group is preferably a (meth)acrylate having a branched chain alkyl group having 3 to 20 carbon atoms in the branched chain alkyl group, and the branched chain alkyl group having 3 to 20 carbon atoms. (Meth)acrylates with branched alkyl groups of 10 are preferred. Examples of (meth)acrylates having a 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, isodecyl (meth)acrylate and the like.

The (meth)acrylate having a cyclic alkyl group is preferably a (meth)acrylate having a cyclic alkyl group having 6 to 12 carbon atoms. Cyclic alkyl groups include cyclic alkyl groups having a monocyclic structure (eg, cycloalkyl groups). Specific examples of (meth)acrylates having a cyclic alkyl group with a monocyclic structure include cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, cyclododecyl (meth)acrylate and the like.

The (meth)acrylate having a polycyclic structure is preferably a (meth)acrylate having a polycyclic structure with 6 to 12 carbon atoms. Polycyclic structures include cyclic alkyl groups having a bridged ring structure (eg, adamantyl, norbornyl, isobornyl groups). Specific examples of (meth)acrylates having a polycyclic structure include isobornyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, 2-methyl-2-adamantyl (Meth)acrylate, 2-ethyl-2-adamantyl (meth)acrylate and the like.

The (meth)acrylate having an aromatic group is preferably a (meth)acrylate having an aromatic group having 6 to 12 carbon atoms. Examples of the aromatic group include an aryl group and the like, and may have a chain portion such as an alkylaryl group, an aralkyl group, an aryloxyalkyl group, and the like. Specific examples of (meth)acrylates having an aromatic group include benzyl (meth)acrylate, phenyl (meth)acrylate, phenoxyethyl (meth)acrylate and the like.

Examples of the (meth)acrylate having a polyalkylene glycol structural unit include polyethylene glycol (degree of polymerization = 2 to 10) methyl ether (meth) acrylate, polyethylene glycol (degree of polymerization = 2 to 10) ethyl ether (meth) acrylate, and polyethylene. Glycol (degree of polymerization = 2 to 10) propyl ether (meth) acrylate, polyethylene glycol (degree of polymerization = 2 to 10) phenyl ether (meth) acrylate having a polyethylene glycol structural unit (meth) acrylate; polypropylene glycol (degree of polymerization = 2 to 10) methyl ether (meth) acrylate, polypropylene glycol (degree of polymerization = 2 to 10) ethyl ether (meth) acrylate, polypropylene glycol (degree of polymerization = 2 to 10) propyl ether (meth) acrylate, polypropylene glycol (polymerization degree=2 to 10) (meth)acrylates having polypropylene glycol structural units such as phenyl ether (meth)acrylates.

Examples of (meth)acrylates having a hydroxy 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, 12-hydroxylauryl (meth)acrylate and the like. Among these, (meth)acrylates having a hydroxyalkyl group having 1 to 5 carbon atoms are more preferred.

Examples of the (meth)acrylate having a lactone-modified hydroxy group include those obtained by adding a lactone to the (meth)acrylate having a hydroxy group, and those obtained by adding caprolactone are preferable. The amount of caprolactone to be added is preferably 1 mol to 10 mol, more preferably 1 mol to 5 mol. Examples of the (meth)acrylate having a lactone-modified hydroxy group include 2-hydroxyethyl (meth)acrylate caprolactone 1 mol adduct, 2-hydroxyethyl (meth)acrylate caprolactone 2 mol adduct, and 2-hydroxyethyl (meth)acrylate. caprolactone 3 mol adduct, 2-hydroxyethyl (meth) acrylate caprolactone 4 mol adduct, 2-hydroxyethyl (meth) acrylate caprolactone 5 mol adduct, 2-hydroxyethyl (meth) acrylate caprolactone 10 mol adduct, etc. are preferable. .

Examples of (meth)acrylates having an alkoxy group include methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate.

The (meth)acrylate having an oxygen-containing heterocyclic group is preferably a (meth)acrylate having a 4- to 6-membered oxygen-containing heterocyclic group. Specific examples of (meth)acrylates having an 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 trimethylolpropane formal (meth)acrylate, 2-[(2-tetrahydropyranyl)oxy]ethyl (meth)acrylate, 1,3-dioxane-(meth)acrylate and the like.

Examples of the acidic group include a carboxy group (--COOH), a sulfonic acid group (--SO ₃ H), a phosphoric acid group (--OPO ₃ H ₂ ), a phosphonic acid group (--PO ₃ H ₂ ), a phosphinic acid group (-- PO ₂ H ₂ ). Examples of (meth)acrylates having an acidic group include (meth)acrylates having a carboxy group, (meth)acrylates having a phosphoric acid group, and (meth)acrylates having a sulfonic acid group.

Examples of (meth)acrylates having a carboxy group include carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, 2-(meth)acryloyloxyethyl succinate, 2-(meth)acryloyloxyethyl maleate, 2- Monomers obtained by reacting (meth)acrylates having a hydroxy group such as (meth)acryloyloxyethyl phthalate with acid anhydrides such as maleic anhydride, succinic anhydride, and phthalic anhydride can be used. Examples of the (meth)acrylate having a sulfonic acid group include ethyl sulfonate (meth)acrylate. Examples of the (meth)acrylate having a phosphoric acid group include 2-(phosphonooxy)ethyl (meth)acrylate.

The A block may have structural units other than structural units derived from (meth)acrylic monomers. Other structural units that can be contained in the A block are not particularly limited as long as they are formed from a vinyl monomer that can be copolymerized with both a (meth)acrylic monomer and a vinyl monomer that forms the B block described below. Vinyl monomers capable of forming other structural units of the A block may be used alone, or two or more of them may be used in combination.

Specific examples of vinyl monomers that can form other structural units of the A block include α-olefins, aromatic vinyl monomers, vinyl monomers containing heterocycles, vinyl carboxylates, and dienes. These vinyl monomers may have a hydroxy group and an epoxy group.

α-olefins include 1-hexene, 1-octene, 1-decene and the like.
Examples of aromatic vinyl monomers include styrene, α-methylstyrene, 4-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methoxystyrene, 2-hydroxymethylstyrene, 1-vinylnaphthalene and the like.
Vinyl monomers containing a heterocycle include 2-vinylthiophene, N-methyl-2-vinylpyrrole, 1-vinyl-2-pyrrolidone, 2-vinylpyridine, 4-vinylpyridine, N-phenylmaleimide, N-benzyl maleimide, N-cyclohexylmaleimide and the like.
Vinyl carboxylate includes vinyl acetate, vinyl pivalate, vinyl benzoate and the like.
Examples of dienes include butadiene, isoprene, 4-methyl-1,4-hexadiene, 7-methyl-1,6-octadiene and the like.

The A block preferably contains a structural unit represented by general formula (10), that is, a structural unit derived from the (meth)acrylate having the lactone-modified hydroxy group. Since the structural unit represented by the general formula (10) has an ester bond portion and a terminal hydroxy group in the side chain, it has a high affinity with the dispersion medium and the binder resin, and the alkali developability of the block copolymer. increase

［一般式（１０）において、ｎ１は１～１０の整数を表す。Ｒ¹は水素原子またはメチル基を表す。Ｒ²は炭素数が１～１０のアルキレン基を表す。Ｒ³は炭素数が１～１０のアルキレン基を表す。］

[In the general formula (10), n1 represents an integer of 1 to 10. R ¹ represents a hydrogen atom or a methyl group. R ² represents an alkylene group having 1 to 10 carbon atoms. R ³ represents an alkylene group having 1 to 10 carbon atoms. ]

n1 in the formula (10) is preferably an integer of 1-7, more preferably an integer of 1-5.

The alkylene group having 1 to 10 carbon atoms represented by R ² may be linear or branched, but is preferably linear. Specific examples of the alkylene group having 1 to 10 carbon atoms represented by R ² include methylene group, ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group, nonamethylene group, decamethylene group, 1-methylethylene group and the like. R ² is preferably an alkylene group having 1 to 5 carbon atoms.

The alkylene group having 1 to 10 carbon atoms represented by R ³ may be linear or branched, but is preferably linear. Specific examples of the alkylene group having 1 to 10 carbon atoms represented by R ³ include methylene group, ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group, A nonamethylene group, a decamethylene group, and the like can be mentioned. R ³ is preferably an alkylene group having 1 to 8 carbon atoms, more preferably an alkylene group having 3 to 8 carbon atoms.

When the A block contains a structural unit represented by the general formula (10), the content is preferably 10% by mass or more, more preferably 20% by mass or more, and still more preferably 100% by mass of the A block. is 30% by mass or more, particularly preferably 60% by mass or more, preferably 95% by mass or less, more preferably 90% by mass or less, and still more preferably 85% by mass or less. By setting the content of the structural unit derived from the (meth)acrylate having a lactone-modified hydroxy group within the above range, the alkali developability of the block copolymer can be enhanced.

The A block preferably has a structural unit derived from a vinyl monomer having an acidic group (preferably (meth)acrylate or (meth)acrylic acid having an acidic group. By having a structural unit derived from a vinyl monomer having an acidic group, the solubility in an alkaline developer is increased, and the alkaline developability can be improved.

When a structural unit derived from a vinyl monomer having an acidic group is contained, the content thereof is preferably 2% by mass or more and preferably 20% by mass or less in 100% by mass of the A block. If the content of the structural unit derived from a vinyl monomer having an acidic group is 2% by mass or more, the dissolution rate becomes faster when neutralized with alkali in alkaline development, and if it is 20% by mass or less, hydrophilicity is high. Therefore, it is possible to prevent the formed pixels from becoming disorderly.

The content of the structural unit represented by the general formula (1) described later in the A block is less than 5% by mass, preferably 3% by mass or less, more preferably 1% by mass or less, and still more preferably 0.1%. It is most preferable not to contain the structural unit represented by the general formula (1) in mass % or less. The lower the total content of the structural units represented by formula (1) in the A block, the better the dispersibility of the coloring material.

When two or more types of structural units are contained in the A block, the various structural units contained in the A block may be contained in any form of random copolymerization, block copolymerization, or the like in the A block. , it is preferably contained in the form of random copolymerization from the viewpoint of uniformity. For example, the A block may be formed of a copolymer of a structural unit consisting of the a1 block and a structural unit consisting of the a2 block.

(B block)
The B block is a polymer block containing a structural unit represented by general formula (1) below.

(Structural unit represented by general formula (1))
The structural unit represented by general formula (1) may be of one kind or may be of two or more kinds. By having the structural unit represented by the general formula (1), the adsorbability with the coloring material is high, and generation of formaldehyde over time can be suppressed.

［一般式（１）において、Ｒ¹¹は水素原子または置換基を有していてもよい鎖状もしくは環状の炭化水素基を表す。Ｒ¹²は置換基を有していてもよい鎖状もしくは環状の炭化水素基を表す。Ｒ¹¹およびＲ¹²が互いに結合して環状構造を形成していてもよい。Ｒ¹³は水素原子またはメチル基を表す。］

[In general formula (1), R ¹¹ represents a hydrogen atom or a chain or cyclic hydrocarbon group which may have a substituent. R ¹² represents a chain or cyclic hydrocarbon group which may have a substituent. R ¹¹ and R ¹² may combine with each other to form a cyclic structure. ^R13 represents a hydrogen atom or a methyl group. ]

Examples of the chain hydrocarbon group represented by R ¹¹ include straight-chain alkyl groups and branched-chain alkyl groups. 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. Examples of the linear alkyl group include methyl group, ethyl group, n-propyl group, n-butyl group, n-hexyl group, n-octyl group, n-nonyl group, n-decyl group and n-lauryl group. is mentioned. The branched-chain 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. Examples of the branched alkyl group include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, 2-ethylhexyl group, neopentyl group and isooctyl group.

Examples of substituents possessed by the chain hydrocarbon group represented by R ¹¹ include a halogen group, an alkoxy group, a benzoyl group (--COC ₆ H ₅ ), and a hydroxy group. The chain hydrocarbon group represented by R ¹¹ preferably does not have an amino group (including a substituted amino group in which a hydrogen atom of an amino group is substituted with an alkyl group) as a substituent.

The cyclic hydrocarbon group represented by R ¹¹ includes a cyclic alkyl group, an aromatic group, and the like, and the cyclic alkyl group and the aromatic group may have a chain portion. The number of carbon atoms in the cyclic alkyl group is preferably 4 to 18 carbon atoms, more preferably 6 to 12 carbon atoms, and even more preferably 6 to 10 carbon atoms. Examples of the cyclic alkyl group include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. The aromatic group preferably has 6 to 18 carbon atoms, more preferably 6 to 12 carbon atoms, and even more preferably 6 to 8 carbon atoms. Examples of the aromatic group include phenyl group, tolyl group, xylyl group and mesityl group. Examples of the chain portion of the cyclic alkyl group having a chain portion and the chain portion of the aromatic group having a chain portion include an alkylene group having 1 to 12 carbon atoms, preferably an alkylene group having 1 to 6 carbon atoms, more preferably a carbon Examples include alkylene groups of numbers 1 to 3.

Examples of substituents possessed by the cyclic hydrocarbon group represented by R ¹¹ include a halogen group, an alkoxy group, a chain alkyl group, and a hydroxy group. The cyclic hydrocarbon group represented by R ¹¹ preferably does not have an amino group (including a substituted amino group in which a hydrogen atom of an amino group is substituted with an alkyl group) as a substituent.

Examples of the chain hydrocarbon group represented by R ¹² include straight-chain alkyl groups and branched-chain alkyl groups. 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. Examples of the linear alkyl group include methyl group, ethyl group, n-propyl group, n-butyl group, n-hexyl group, n-octyl group, n-nonyl group, n-decyl group and n-lauryl group. are mentioned. The branched-chain 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. Examples of the branched alkyl group include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, 2-ethylhexyl group, neopentyl group and isooctyl group.

Examples of substituents possessed by the chain hydrocarbon group represented by R ¹² include a halogen group, an alkoxy group, a benzoyl group (--COC ₆ H ₅ ), and a hydroxy group. The chain hydrocarbon group represented by R ¹² preferably does not have an amino group (including a substituted amino group in which a hydrogen atom of an amino group is substituted with an alkyl group) as a substituent.

The cyclic hydrocarbon group represented by R ¹² includes a cyclic alkyl group, an aromatic group, and the like, and the cyclic alkyl group and the aromatic group may have a chain portion. The number of carbon atoms in the cyclic alkyl group is preferably 4 to 18 carbon atoms, more preferably 6 to 12 carbon atoms, and even more preferably 6 to 10 carbon atoms. Examples of the cyclic alkyl group include a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. The aromatic group preferably has 6 to 18 carbon atoms, more preferably 6 to 12 carbon atoms, and even more preferably 6 to 8 carbon atoms. Examples of the aromatic group include phenyl group, tolyl group, xylyl group and mesityl group. Examples of the chain portion of the cyclic alkyl group having a chain portion and the chain portion of the aromatic group having a chain portion include an alkylene group having 1 to 12 carbon atoms, preferably an alkylene group having 1 to 6 carbon atoms, more preferably a carbon Examples include alkylene groups of numbers 1 to 3.

Examples of substituents of the cyclic hydrocarbon group represented by R ¹² include a halogen group, an alkoxy group, a chain alkyl group, and a hydroxy group. The cyclic hydrocarbon group represented by R ¹² preferably does not have an amino group (including a substituted amino group in which a hydrogen atom of an amino group is substituted with an alkyl group) as a substituent.

Examples of the cyclic structure formed by combining R ¹¹ and R ¹² include a 5- to 7-membered nitrogen-containing hetero ring or a condensed ring formed by condensing two of these. The nitrogen-containing heterocyclic ring preferably has no aromaticity, more preferably a saturated ring. Specific examples include structures represented by the following formulas (1-1), (1-2), and (1-3).

［一般式（１－１）、（１－２）、（１－３）において、Ｒ¹⁴は、炭素数１～６のアルキル基を示す。ｌは０～５の整数を表す。ｍは０～４の整数を表す。ｎは０～４の整数を表す。＊は結合手を表す。ｌが２～５、ｍが２～４、ｎが２～４の場合、複数存在するＲ¹⁴は、それぞれ同一でも異なっていてもよい。］

[In general formulas (1-1), (1-2) and (1-3), R ¹⁴ represents an alkyl group having 1 to 6 carbon atoms. l represents an integer of 0 to 5; m represents an integer of 0 to 4; n represents an integer of 0 to 4; * represents a bond. When l is 2 to 5, m is 2 to 4, and n is 2 to 4, a plurality of R ¹⁴ may be the same or different. ]

Specific examples of the vinyl monomer forming the structural unit represented by general formula (1) include N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-diisopropyl(meth) dialkyl(meth)acrylamides such as acrylamide; cyclic amides such as N-(meth)acryloylmorpholine; alkoxyalkylacrylamides such as N-methoxymethylacrylamide and N-ethoxymethylacrylamide; Among these, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide and N-(meth)acryloylmorpholine are preferred.

The B block may consist only of structural units represented by general formula (1), or may contain other structural units. From the viewpoint of maintaining affinity with the coloring material, the content of the structural unit represented by general formula (1) in the B block is preferably 80% by mass or more, more preferably 90% by mass, based on 100% by mass of the B block. It is at least 95% by mass, more preferably at least 95% by mass. Moreover, it is preferable that the B block does not substantially contain a structural unit derived from a vinyl monomer having an acidic group. That is, the content of the structural unit derived from the vinyl monomer having an acidic group is preferably 5% by mass or less, more preferably 2% by mass or less, in 100% by mass of the B block.

Specific examples of the vinyl monomer that can form other structural units of the B block are the same as those given as specific examples of the vinyl monomer that can form other structural units of the A block.

When two or more types of structural units are contained in the B block, the various structural units contained in the B block may be contained in any manner such as random copolymerization or block copolymerization in the B block. , it is preferably contained in the form of random copolymerization from the viewpoint of uniformity. For example, the B block may be formed of a copolymer of a structural unit consisting of the b1 block and a structural unit consisting of the b2 block.

(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, the A block is A and the B block is B When expressed as, the group consisting of (AB) _m type, _{(AB) m - A type, (B-A) m -} B type (m is an integer of 1 or more, for example, an integer of 1 to 3) A copolymer having at least one structure selected from is preferred. Among these, AB type diblock copolymers are preferred from the viewpoint of handling during processing and physical properties of the composition. By forming an AB type diblock copolymer, the structural unit derived from the (meth)acrylic monomer in the A block and the structural unit represented by the general formula (1) in the B block are localized. It is considered that the coloring agent, the dispersing medium (solvent), and the binder resin (alkali-soluble resin) can act efficiently and favorably. The block copolymer may have blocks other than the A block and the B block.

The content of the A block is preferably 35% by mass or more, more preferably 40% by mass or more, still more preferably 45% by mass or more, and preferably 85% by mass or less, based on 100% by mass of the entire block copolymer. More preferably 80% by mass or less, still more preferably 75% by mass or less. The content of the B block is preferably 15% by mass or more, more preferably 20% by mass or more, still more preferably 25% by mass or more, and preferably 65% by mass or less, based on 100% by mass of the entire block copolymer. More preferably 60% by mass or less, still more preferably 55% by mass or less. By adjusting the content of the A block and the B block within the above range, the dispersing performance is further improved when used as a dispersant.

The mass ratio of the A block and the B block (A block/B block) in the block copolymer is preferably 50/50 or more, more preferably 55/45 or more, still more preferably 60/40 or more, and 95 /5 or less, more preferably 90/10 or less, and still more preferably 80/20 or less. If the mass ratio of the A block and the B block is within the above range, the dispersing performance when used as a dispersant is further improved.

When the block copolymer contains a structural unit having an acidic group, the content of the structural unit derived from a vinyl monomer having an acidic group in the block copolymer is preferably 1% by mass or more and 10% by mass or less. is preferred.

The content of the structural unit represented by the general formula (1) in the block copolymer is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 20% by mass or more, and 50% by mass. % or less, more preferably 45 mass % or less, and even more preferably 40 mass % or less.

The molecular weight of the block copolymer is measured by a gel permeation chromatography (hereinafter referred to as "GPC") method. The weight average molecular weight (Mw) of the block copolymer is preferably 3,000 or more, more preferably 4,000 or more, still more preferably 5,000 or more, and particularly preferably 6,000 or more. 000 or less, more preferably 30,000 or less, still more preferably 25,000 or less, and particularly preferably 20,000 or less. If the weight-average molecular weight is within the above range, the dispersion performance when used as a dispersant will be better.

The molecular weight distribution (PDI) of the block copolymer is preferably 2.5 or less, more preferably 2.0 or less, and even more preferably 1.6 or less. In the present invention, the molecular weight distribution (PDI) is determined by (weight average molecular weight (Mw) of block copolymer)/(number average molecular weight (Mn) of block copolymer). The smaller the PDI, the narrower the width of the molecular weight distribution, the more uniform the molecular weight of the copolymer. When the value is 1.0, the narrowest molecular weight distribution. That is, the lower limit of PDI is 1.0. When the molecular weight distribution (PDI) of the block copolymer exceeds 2.5, it includes those with small molecular weights and those with large molecular weights.

From the viewpoint of reducing the amount of formaldehyde generated over time, the block copolymer preferably does not have an amino group. In other words, it is preferable that the vinyl monomer constituting the block copolymer does not contain a vinyl monomer having an amino group. The content of structural units derived from a vinyl monomer having an amino group in the block copolymer (including those in which the amino group is quaternized) is preferably 2% by mass or less, more preferably 1% by mass. Below, more preferably 0.1% by mass or less, most preferably 0% by mass. The amine value of the block copolymer is preferably less than 10 mgKOH/g, more preferably less than 5 mgKOH/g, still more preferably less than 3 mgKOH/g, and most preferably 0 mgKOH/g.

When the block copolymer contains a structural unit having an acidic group, the block copolymer preferably has an acid value of 5 mgKOH/g or more and preferably 50 mgKOH/g or less. By setting the acid value within this range, it can act favorably with the binder resin (alkali-soluble resin) without impairing the affinity of the block copolymer for the colorant.

(Method for producing block copolymer)
As a method for producing the block copolymer, the A block is first produced by the polymerization reaction of the vinyl monomer, and the B block is polymerized on the A block; A method of polymerizing block monomers; a method of separately producing blocks A and B and then coupling the blocks A and B;

Although the polymerization method is not particularly limited, living radical polymerization is preferred. That is, the block copolymer is preferably polymerized by living radical polymerization. In the conventional radical polymerization method, not only initiation reaction and propagation reaction but also termination reaction and chain transfer reaction cause deactivation of propagating terminal, and tend to result in a mixture of polymers with various molecular weights and non-uniform compositions. On the other hand, the living radical polymerization method maintains the simplicity and versatility of the conventional radical polymerization method. It is preferable in that it is easy to precisely control and manufacture a polymer with a uniform composition.

Living radical polymerization methods include a method using a transition metal catalyst (ATRP method); a method using a sulfur-based reversible chain transfer agent (RAFT method); There is a method such as a method (TERP method). Since the ATRP method uses an amine-based complex, it may not be possible to use it without protecting the acidic group of the vinyl monomer having an acidic group. In the RAFT method, when a variety of monomers are used, it is difficult to obtain a low molecular weight distribution, and problems such as sulfur odor and coloration may occur. Among these methods, it is preferable to use the TERP method from the viewpoint of the diversity of usable monomers, molecular weight control in the high molecular region, uniform composition, or coloring.

The TERP method is a method of polymerizing a radically polymerizable compound (vinyl monomer) using an organic tellurium compound as a chain transfer agent. 2004/072126 and methods described in WO 2004/096870.

Specific polymerization methods for the TERP method include the following (a) to (d).
(a) A vinyl monomer is polymerized using an organic tellurium compound represented by general formula (3).
(b) A vinyl monomer is polymerized using a mixture of an organic tellurium compound represented by general formula (3) and an azo polymerization initiator.
(c) A vinyl monomer is polymerized using a mixture of an organic tellurium compound represented by general formula (3) and an organic ditelluride compound represented by general formula (4).
(d) A vinyl monomer is polymerized using a mixture of an organic tellurium compound represented by general formula (3), an azo polymerization initiator, and an organic ditelluride compound represented by general formula (4).

［一般式（３）において、Ｒ³¹は、炭素数１～８のアルキル基、アリール基または芳香族ヘテロ環基を示す。Ｒ³²およびＲ³³は、それぞれ独立に、水素原子または炭素数１～８のアルキル基を示す。Ｒ³⁴は、炭素数１～８のアルキル基、アリール基、置換アリール基、芳香族ヘテロ環基、アルコキシ基、アシル基、アミド基、オキシカルボニル基、シアノ基、アリル基またはプロパルギル基を示す。
一般式（４）において、Ｒ³¹は、炭素数１～８のアルキル基、アリール基または芳香族ヘテロ環基を示す。］

[In general formula (3), R ³¹ represents an alkyl group having 1 to 8 carbon atoms, an aryl group or an aromatic heterocyclic group. R ³² and R ³³ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. R ³⁴ represents an alkyl group having 1 to 8 carbon atoms, an aryl group, a substituted aryl group, an aromatic heterocyclic group, an alkoxy group, an acyl group, an amide group, an oxycarbonyl group, a cyano group, an allyl group or a propargyl group.
In general formula (4), R ³¹ represents an alkyl group having 1 to 8 carbon atoms, an aryl group or an aromatic heterocyclic group. ]

The group represented by R ³¹ is an alkyl group having 1 to 8 carbon atoms, an aryl group or an aromatic heterocyclic group, and specific examples are as follows.
Examples of alkyl groups having 1 to 8 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group and heptyl. linear or branched alkyl groups such as radicals, octyl groups, and cyclic alkyl groups such as cyclohexyl groups. A linear or branched alkyl group having 1 to 4 carbon atoms is preferable, and a methyl group or an ethyl group is more preferable.
A phenyl group, a naphthyl group, etc. can be mentioned as an aryl group.
A pyridyl group, a furyl group, a thienyl group, etc. can be mentioned as an aromatic heterocyclic group.

The groups represented by R ³² and R ³³ are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and specific examples of each group are as follows.
Examples of alkyl groups having 1 to 8 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group and heptyl. linear or branched alkyl groups such as radicals, octyl groups, and cyclic alkyl groups such as cyclohexyl groups. A linear or branched alkyl group having 1 to 4 carbon atoms is preferable, and a methyl group or an ethyl group is more preferable.

The group represented by R ³⁴ is an alkyl group having 1 to 8 carbon atoms, an aryl group, a substituted aryl group, an aromatic heterocyclic group, an alkoxy group, an acyl group, an amide group, an oxycarbonyl group, a cyano group, an allyl group or It is a propargyl group, specifically as follows.
Examples of alkyl groups having 1 to 8 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group and heptyl. linear or branched alkyl groups such as octyl groups, cyclic alkyl groups such as cyclohexyl groups, and the like. A linear or branched alkyl group having 1 to 4 carbon atoms is preferable, and a methyl group or an ethyl group is more preferable.
A phenyl group, a naphthyl group, etc. can be mentioned as an aryl group. A phenyl group is preferred.
Examples of the substituted aryl group include a phenyl group having a substituent, a naphthyl group having a substituent, and the like. Examples of the substituents of the aryl group having the above-mentioned substituents include halogen atoms, hydroxy groups, alkoxy groups, amino groups, nitro groups, cyano groups, and carbonyl-containing groups represented by —COR ³⁴¹ (R ³⁴¹ is a carbon 1 to 8 alkyl groups, aryl groups, C 1 to 8 alkoxy groups or aryloxy groups), sulfonyl groups, trifluoromethyl groups and the like. Moreover, it is preferable that one or two of these substituents are substituted.
A pyridyl group, a furyl group, a thienyl group, etc. can be mentioned as an aromatic heterocyclic group.
The alkoxy group is preferably a group in which an alkyl group having 1 to 8 carbon atoms is bonded to an oxygen atom. butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group and the like.
Acyl groups include acetyl, propionyl, and benzoyl groups.
Examples of amide groups include -CONR ³⁴²¹ R ³⁴²² (R ³⁴²¹ and R ³⁴²² are each independently a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or an aryl group).
The oxycarbonyl group is preferably a group represented by —COOR ³⁴³¹ (R ³⁴³¹ is a hydrogen atom, an alkyl group having 1 to 8 carbon atoms or an aryl group), such as a carboxy group, a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group. group, n-butoxycarbonyl group, sec-butoxycarbonyl group, tert-butoxycarbonyl group, n-pentyloxycarbonyl group, phenoxycarbonyl group and the like. Preferred oxycarbonyl groups include methoxycarbonyl and ethoxycarbonyl groups.
The allyl group includes -CR ³⁴⁴¹ R ³⁴⁴² -CR ³⁴⁴³ =CR ³⁴⁴⁴ R ³⁴⁴⁵ (R ³⁴⁴¹ and R ³⁴⁴² are each independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, R ³⁴⁴³ , R ³⁴⁴⁴ and R ³⁴⁴⁵ are , each independently a hydrogen atom, an alkyl group or an aryl group having 1 to 8 carbon atoms, and each substituent may be connected in a cyclic structure).
The propargyl group includes —CR ³⁴⁵¹ R ³⁴⁵² —C≡CR ³⁴⁵³ (R ³⁴⁵¹ and R ³⁴⁵² are a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, R ³⁴⁵³ is a hydrogen atom or an alkyl group having 1 to 8 carbon atoms , an aryl group or a silyl group) and the like.

Specifically, the organic tellurium compound represented by the general formula (3) is (methyltheranylmethyl)benzene, (methyltheranylmethyl)naphthalene, ethyl-2-methyl-2-methyltheranyl-propionate, ethyl-2- methyl-2-n-butyltheranyl-propionate, (2-trimethylsiloxyethyl)-2-methyl-2-methyltheranyl-propionate, (2-hydroxyethyl)-2-methyl-2-methyltheranyl-propionate or (3-trimethylsilylpropargyl )-2-methyl-2-methylteranyl-propionate, etc., organic All tellurium compounds can be exemplified.

Specific examples of the organic ditelluride compound represented by the general formula (4) include dimethyl ditelluride, diethyl ditelluride, di-n-propyl ditelluride, diisopropyl ditelluride, dicyclopropyl ditelluride, di -n-butyl ditelluride, di-s-butyl ditelluride, di-t-butyl ditelluride, dicyclobutyl ditelluride, diphenyl ditelluride, bis-(p-methoxyphenyl) ditelluride, bis-(p-aminophenyl) ditelluride, bis -(p-Nitrophenyl)ditelluride, bis-(p-cyanophenyl)ditelluride, bis-(p-sulfonylphenyl)ditelluride, dinaphthylditelluride, dipyridylditelluride and the like can be exemplified.

As the azo polymerization initiator, any azo polymerization initiator that is commonly used in radical polymerization can be used without any particular limitation. For example, 2,2′-azobis(isobutyronitrile) (AIBN), 2,2′-azobis(2-methylbutyronitrile) (AMBN), 2,2′-azobis(2,4-dimethylvaleronitrile) ) (ADVN), 1,1′-azobis(1-cyclohexanecarbonitrile) (ACHN), dimethyl-2,2′-azobisisobutyrate (MAIB), 4,4′-azobis(4-cyanovaleric acid ) (ACVA), 1,1′-azobis(1-acetoxy-1-phenylethane), 2,2′-azobis(2-methylbutyramide), 2,2′-azobis(4-methoxy-2,4 -dimethylvaleronitrile) (V-70), 2,2′-azobis(2-methylamidinopropane) dihydrochloride, 2,2′-azobis[2-(2-imidazolin-2-yl)propane], 2 , 2′-azobis[2-methyl-N-(2-hydroxyethyl)propionamide], 2,2′-azobis(2,4,4-trimethylpentane), 2-cyano-2-propylazoformamide, 2 , 2′-azobis(N-butyl-2-methylpropionamide) or 2,2′-azobis(N-cyclohexyl-2-methylpropionamide).

The polymerization step is carried out in a vessel purged with an inert gas, with a vinyl monomer and an organic tellurium compound of general formula (3) for the purpose of promoting the reaction, controlling the molecular weight and molecular weight distribution, etc., depending on the type of the vinyl monomer, and further adding an azo A system polymerization initiator and/or an organic ditelluride compound of general formula (4) is mixed. At this time, examples of the inert gas include nitrogen, argon, and helium. Argon and nitrogen are preferred.

The amount of the vinyl monomer used in (a), (b), (c) and (d) may be appropriately adjusted according to the physical properties of the desired copolymer. It is preferable to use 5 mol to 10000 mol of the vinyl monomer per 1 mol of the organic tellurium compound of general formula (3).

When the organic tellurium compound of general formula (3) and the azo polymerization initiator (b) are used in combination, 0.01 mol to 10 mol of the azo polymerization initiator is used per 1 mol of the organic tellurium compound of general formula (3). It is preferable to

When the organic tellurium compound of general formula (3) in (c) and the organic ditelluride compound of general formula (4) are used in combination, the organic tellurium compound of general formula (4) is used per 1 mol of the organic tellurium compound of general formula (3). The amount of the ditelluride compound is preferably 0.01 mol to 100 mol.

When the organic tellurium compound of general formula (3) in (d) above, the organic ditelluride compound of general formula (4), and an azo polymerization initiator are used in combination, generally per 1 mol of the organic tellurium compound of general formula (3) The organic ditelluride compound of formula (4) is preferably 0.01 mol to 100 mol, and the azo polymerization initiator is preferably 0.01 mol to 10 mol per 1 mol of the organic tellurium compound of general formula (3).

The polymerization reaction can be carried out without a solvent, but may be carried out by using an aprotic or protic solvent generally used in radical polymerization and stirring the mixture. Aprotic solvents that can be used are, for example, anisole, benzene, toluene, N,N-dimethylformamide (DMF), dimethylsulfoxide (DMSO), acetone, 2-butanone (methyl ethyl ketone), dioxane, propylene glycol monomethyl ether acetate, chloroform. , carbon tetrachloride, tetrahydrofuran (THF), ethyl acetate, trifluoromethylbenzene, and the like. Examples of protic solvents include water, methanol, ethanol, isopropanol, n-butanol, ethyl cellosolve, butyl cellosolve, 1-methoxy-2-propanol, hexafluoroisopropanol and diacetone alcohol.

The amount of the solvent to be used may be adjusted as appropriate. For example, it is preferably 0.01 ml or more, more preferably 0.05 ml or more, still more preferably 0.1 ml or more, and 50 ml or less per 1 g of the vinyl monomer. It is preferably 10 ml or less, more preferably 1 ml or less.

The reaction temperature and reaction time may be appropriately adjusted depending on the molecular weight or molecular weight distribution of the resulting copolymer, but the mixture is usually stirred at 0°C to 150°C for 1 minute to 100 hours. The TERP method can obtain high yields and precise molecular weight distributions even at low polymerization temperatures and short polymerization times. At this time, the pressure is usually normal pressure, but may be pressurized or reduced.

After completion of the polymerization reaction, the desired copolymer can be separated from the resulting reaction mixture by removing the used solvent, residual vinyl monomers, and the like by ordinary separation and purification means.

The growing terminal of the copolymer obtained by the polymerization reaction is in the form of —TeR ³¹ (wherein R ³¹ is the same as above) derived from the tellurium compound, and is deactivated by an operation in air after the completion of the polymerization reaction. However, tellurium atoms may remain. Since a copolymer having a tellurium atom remaining at the end thereof is colored or has poor thermal stability, it is preferable to remove the tellurium atom.

Methods for removing tellurium atoms include radical reduction methods using tributylstannane or thiol compounds; adsorption methods using activated carbon, silica gel, activated alumina, activated clay, molecular sieves, polymer adsorbents, etc.; ion exchange resins, etc. Method of adsorbing metals: Hydrogen peroxide solution or peroxides such as benzoyl peroxide are added, air or oxygen is blown into the system to oxidize and decompose the tellurium atoms at the ends of the copolymer, washing with water or appropriate A liquid-liquid extraction method or a solid-liquid extraction method that removes residual tellurium compounds by combining solvents; a purification method in a solution state such as ultrafiltration that extracts and removes only those with a specific molecular weight or less can be used. , or a combination of these methods can be used.

The other end of the copolymer obtained by the polymerization reaction (the end opposite to the growing end) is -CR ³² R ³³ R ³⁴ derived from a tellurium compound (wherein R ³² , R ³³ and R ³⁴ are represented by the formula The same as R ³² , R ³³ and R ³⁴ in (3)).

(polymerization product)
The dispersant composition may use a polymerization product containing the block copolymer as a dispersant component. The polymerization product refers to a product obtained when a polymerization operation is performed to obtain the block copolymer. The polymerization product contains the desired block copolymer and polymer impurities by-produced during the synthesis of this block copolymer.

The polymer impurities are other polymers that are inevitably by-produced when synthesizing the desired block copolymer. For example, polymer impurities by-produced when synthesizing an AB diblock copolymer include random polymers having the same composition as the A block and random polymers having the same composition as the B block. Polymer impurities are polymers that are by-produced when synthesizing the desired block copolymer, and do not include polymers that are added separately.

The content of the block copolymer in the polymerization product is preferably 50% by mass or more in 100% by mass of the polymerization product. If the content of the block copolymer in the polymerized product is 50% by mass or more, the dispersing performance is improved when the polymerized product is used as a dispersant.

(dispersion medium)
The dispersant composition may contain a dispersing medium. The dispersing medium can be appropriately selected and used as long as it disperses or dissolves the block copolymer, does not react with these components, and has moderate volatility. For example, conventionally known organic solvents can be used, such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene Glycol mono-n-butyl ether, propylene glycol-t-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, methoxymethylpentanol, methoxypropanol, propylene glycol monoethyl ether, dipropylene glycol monoethyl ether , dipropylene glycol monomethyl ether, 3-methyl-3-methoxybutanol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, glycol monoalkyl ethers such as tripropylene glycol methyl ether; ethylene glycol dimethyl ether, ethylene glycol diethyl ether , diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, glycol dialkyl ethers such as dipropylene glycol dimethyl ether; 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 , glycol alkyl ether acetates such as diethylene glycol mono-n-butyl ether acetate, dipropylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether acetate, triethylene glycol monoethyl ether acetate, 3-methyl-3-methoxybutyl acetate; ethylene glycol Glycol diacetates such as diacetate, 1,3-butylene glycol diacetate, 1,6-hexanediol diacetate; Alkyl acetates such as cyclohexanol acetate; Amyl ether, propyl ether, diethyl ether, dipropyl ether, diisopropyl ether Ethers such as ether, butyl ether, diamyl ether, ethyl isobutyl ether, dihexyl ether; acetone, methyl ethyl ketone, methyl amyl ketone, methyl isopropyl ketone, methyl isoamyl ketone, diisopropyl ketone, diisobutyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl amyl ketone , methyl butyl ketone, methyl hexyl ketone, methyl nonyl ketone, methoxymethylpentanone, and other ketones; ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol, propylene glycol, butanediol, diethylene glycol, dipropylene glycol, triethylene monohydric or polyhydric alcohols such as glycol, glycerin and benzyl alcohol; aliphatic hydrocarbons such as n-pentane, n-octane, diisobutylene, n-hexane, hexene, isoprene, dipentene and dodecane; cyclohexane and methylcyclohexane , methylcyclohexene, bicyclohexyl and other alicyclic hydrocarbons; benzene, toluene, xylene, cumene and other aromatic hydrocarbons; 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, 3-ethoxy Chain or cyclic esters such as ethyl propionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, γ-butyrolactone; 3-methoxypropionic acid, alkoxycarboxylic acids such as 3-ethoxypropionic acid; halogenated hydrocarbons such as butyl chloride and amyl chloride; ether ketones such as methoxymethylpentanone; nitriles such as acetonitrile and benzonitrile.

The content of the dispersion medium in the dispersant composition is not particularly limited and can be adjusted as appropriate. The upper limit of the content of the dispersing medium in the dispersant composition is usually 99% by mass. The lower limit of the content of the dispersing medium in the dispersant composition is usually 10% by mass, preferably 30% by mass, in consideration of the viscosity suitable for producing the colored composition described later.

<Coloring composition>
The coloring composition of the present invention contains the dispersant composition, a coloring material, a binder resin and a dispersion medium.

(colorant)
The type of the coloring material may be appropriately selected according to its use, and examples thereof include pigments and dyes. From the viewpoint of light resistance and heat resistance, the coloring composition preferably contains a pigment as a coloring agent. As the pigment, either an organic pigment or an inorganic pigment may be used, but an organic pigment containing an organic compound as a main component is particularly preferable. Examples of pigments include pigments of various colors such as red pigments, yellow pigments, orange pigments, blue pigments, green pigments, and purple pigments. The structure of the pigment includes azo pigments such as monoazo pigments, diazo pigments, condensed diazo pigments, diketopyrrolopyrrole pigments, phthalocyanine pigments, isoindolinone pigments, isoindoline pigments, quinacridone pigments, and indigo pigments. polycyclic pigments such as polycyclic pigments, thioindigo pigments, quinophthalone pigments, dioxazine pigments, anthraquinone pigments, perylene pigments, and perinone pigments. The pigment contained in the coloring composition may be of only one type, or may be of multiple types.

Specific examples of pigments include C.I. 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, 166, 168, red pigments such as C.I. I. Pigment Yellow 1, 3, 5, 6, 14, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 93, 97, 98, 104, 108, 110, 138, 139, 147, yellow pigments such as C.I. I. Orange pigments such as C.I. Pigment Orange 36, 38, 43; I. Blue pigments such as C.I. Pigment Blue 15, 15:2, 15:3, 15:4, 15:6, 16, 22, 60; I. Pigment Green 7, 36, 58, 59, 62, 63, aluminum phthalocyanine, polyhalogenated aluminum phthalocyanine, aluminum phthalocyanine hydroxide, diphenoxyphosphinyloxyaluminum phthalocyanine, diphenylphosphinyloxyaluminum phthalocyanine, polyhalogenated diphenoxy Green pigments such as phosphinyloxyaluminum phthalocyanine, polyhalogenated diphenylphosphinyloxyaluminum phthalocyanine; C.I. I. Purple pigments such as Pigment Violet 23, 32, 50 and the like are included. Among these pigments, C.I. I. Pigment Red 254, C.I. I. Pigment Red 255, C.I. I. Pigment Red 264, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15:2, C.I. I. Pigment Blue 15:3, C.I. I. Pigment Blue 15:4, C.I. I. Pigment Blue 15:6, C.I. I. Pigment Blue 16, C.I. I. Pigment Green 7, C.I. I. Pigment Green 36, C.I. I. Pigment Green 58, C.I. I. Pigment Green 59 and the like are preferred.

When the coloring composition of the present invention is used to form a light shielding material such as a black matrix of a color filter, a black pigment can be used. A black pigment may be used alone, or a mixture of the red pigment, the green pigment, the blue pigment, and the like may be used. Examples of black pigments include carbon black, acetylene black, lamp black, bone black, graphite, iron black, and titanium black. Among these, carbon black and titanium black are preferable from the viewpoint of light shielding rate and image characteristics.

The average particle size of the coloring material may be appropriately selected according to its use, and is not particularly limited. From the viewpoint of high transparency and high contrast, the coloring composition preferably contains a coloring material having an average particle size of 10 nm to 150 nm.

The coloring material may contain a pigment derivative as a dispersing aid. As the dye derivative, it is preferable to contain an acidic dye derivative having an acidic group in order to form an ionic bond with an amide group in the polymer contained in the dispersant composition for adsorption. This dye derivative has an acidic functional group introduced into the dye skeleton. As the pigment skeleton, a skeleton identical or similar to that of the coloring material constituting the coloring composition, and a skeleton identical or similar to that of the compound that is the raw material of the pigment are preferable. Specific examples of the dye skeleton include an azo dye skeleton, a phthalocyanine dye skeleton, an anthraquinone dye skeleton, a triazine dye skeleton, an acridine dye skeleton, and a perylene dye skeleton. A carboxy group, a phosphoric acid group, and a sulfonic acid group are preferable as the acidic group to be introduced into the dye skeleton. A sulfonic acid group is preferred for the convenience of synthesis and for its strong acidity. The acidic group may be directly bonded to the dye skeleton, or may be bonded to the dye skeleton via a hydrocarbon group such as an alkyl group or an aryl group; an ester, ether, sulfonamide or urethane bond. The amount of the pigment derivative to be used is not particularly limited, but it is preferably 4 parts by mass to 17 parts by mass with respect to 100 parts by mass of the colorant.

The upper limit of the content of the coloring material in the coloring composition, from the viewpoint of brightness, in the total solid content of the coloring composition is usually 80% by mass, preferably 70% by mass, and 60% by mass. is more preferable. Further, the lower limit of the content of the coloring agent in the coloring composition is usually 10% by mass, preferably 20% by mass, more preferably 30% by mass in the total solid content of the coloring composition. preferable. Here, the solid content is a component other than the dispersion medium, which will be described later.

The content of the dispersant component (block copolymer and polymerization product) for the colorant in the coloring composition is preferably 5 parts by mass to 200 parts by mass with respect to 100 parts by mass of the colorant, and 10 parts by mass to It is preferably 100 parts by mass, more preferably 10 to 80 parts by mass.

(binder resin)
The coloring composition contains a binder resin (excluding a polymer having a structural unit represented by the general formula (1)). Thereby, the alkali developability of the coloring composition and the binding property to the substrate can be improved. Although such a binder resin is not particularly limited, it is preferably a resin having an acidic group such as a carboxy group or a phenolic hydroxy group.

As the binder resin, a random copolymer containing a structural unit derived from a carboxy group-containing vinyl monomer and a structural unit derived from (meth)acrylate is preferable. As the carboxy group-containing vinyl monomer, (meth)acrylic acid is preferable. Examples of the (meth)acrylate include methyl (meth)acrylate, butyl (meth)acrylate, and benzyl (meth)acrylate.

In the binder resin, the total content of the structural unit derived from the carboxy group-containing vinyl monomer and the structural unit derived from (meth)acrylate is preferably 50% by mass or more, more preferably 60% by mass or more, and still more preferably It is 70% by mass or more. In the binder resin, the content of the structure derived from the carboxy group-containing vinyl monomer is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 20% by mass or more, and 90% by mass or less. is preferred, and more preferably 70% by mass or less.

Among these, random copolymers of carboxy group-containing vinyl monomers and (meth)acrylates are preferred. Specific examples of such copolymers include random copolymers of (meth)acrylic acid and butyl (meth)acrylate, random copolymers of (meth)acrylic acid and benzyl (meth)acrylate, (meth) ) Random copolymers of acrylic acid, butyl (meth)acrylate and benzyl (meth)acrylate. From the viewpoint of affinity between the binder resin and the coloring material, the binder resin is particularly preferably a random copolymer of (meth)acrylic acid and benzyl (meth)acrylate.

In the copolymer of the carboxy group-containing vinyl monomer and (meth)acrylate, the content of (meth)acrylic acid is usually 5% to 90% by mass, and 10% to 70% by mass, based on the total monomer components. and more preferably 20% by mass to 70% by mass.

The binder resin may have a radically polymerizable carbon-carbon double bond in its side chain. By having a double bond in the side chain, the photocurability of the colored composition according to the present invention is enhanced, so that resolution and adhesion can be further improved. Examples of methods for introducing radically polymerizable carbon-carbon double bonds to side chains include glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, o- (or m-, or p- ) A method of reacting a compound such as vinylbenzyl glycidyl ether with the acidic group of the binder resin.

The Mw of the binder resin is preferably 3,000 to 100,000, more preferably 5,000 to 50,000, even more preferably 5,000 to 20,000. When the Mw of the binder resin is 3,000 or more, the colored layer formed from the coloring composition has good heat resistance, film strength, etc., and when the Mw is 100,000 or less, the alkali developability of the coating film is even better.

The acid value of the binder resin is preferably 20 mgKOH/g to 170 mgKOH/g, more preferably 50 mgKOH/g to 150 mgKOH/g, even more preferably 90 mgKOH/g to 150 mgKOH/g. When the acid value of the binder resin is 20 mgKOH/g or more, the alkali developability when the coloring composition is used as a colored layer is further improved, and when it is 170 mgKOH/g or less, the heat resistance is improved.

The binder resin contained in the coloring composition may be of only one type, or may be of a plurality of types. In the coloring composition, the content of the binder resin is preferably 3 parts by mass to 200 parts by mass with respect to 100 parts by mass of the coloring material, more preferably 10 parts by mass to 100 parts by mass, 20 parts by mass parts to 80 parts by mass is more preferable.

(crosslinking agent)
The coloring composition may contain a cross-linking agent, if necessary. A cross-linking agent refers to a compound having two or more polymerizable groups. Examples of polymerizable groups include ethylenically unsaturated groups, oxiranyl groups, oxetanyl groups, N-alkoxymethylamino groups and the like. The cross-linking agent is preferably a compound having two or more (meth)acryloyl groups or a compound having two or more N-alkoxymethylamino groups.

Specific examples of the compound having two or more (meth)acryloyl groups include a polyfunctional (meth)acrylate obtained by reacting an aliphatic polyhydroxy compound with (meth)acrylic acid, a caprolactone-modified polyfunctional ( meth)acrylates, alkylene oxide-modified polyfunctional (meth)acrylates, polyfunctional urethane (meth)acrylates obtained by reacting hydroxy group-containing (meth)acrylates with polyfunctional isocyanates, hydroxy group-containing (meth)acrylates and a polyfunctional (meth)acrylate having a carboxy group obtained by reacting an acid anhydride.

Examples of the aliphatic polyhydroxy compounds include divalent aliphatic polyhydroxy compounds such as ethylene glycol, propylene glycol, polyethylene glycol, and polypropylene glycol; of aliphatic polyhydroxy compounds. Examples of (meth)acrylates having a hydroxy group include, for example, 2-hydroxyethyl (meth)acrylate, trimethylolpropane di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, di pentaerythritol hexa(meth)acrylate, glycerol di(meth)acrylate and the like. Examples of the polyfunctional isocyanate include tolylene diisocyanate, hexamethylene diisocyanate, diphenylmethylene diisocyanate, and isophorone diisocyanate. Examples of the acid anhydride include anhydrides of dibasic acids such as succinic anhydride, maleic anhydride, glutaric anhydride, itaconic anhydride, phthalic anhydride, and hexahydrophthalic anhydride; pyromellitic anhydride and biphenyltetracarboxylic acid. Tetrabasic acid dianhydrides such as acid dianhydrides and benzophenonetetracarboxylic acid dianhydrides can be mentioned.

In the coloring composition, the content of the cross-linking agent is preferably 10 parts by mass to 1,000 parts by mass, particularly preferably 20 parts by mass to 500 parts by mass, based on 100 parts by mass of the coloring material. If the content of the cross-linking agent is too small, there is a possibility that sufficient curability cannot be obtained. On the other hand, if the amount of the cross-linking agent is too large, the colored composition of the present invention will have reduced alkali developability, and scumming, film residue, etc. tend to occur easily on the substrate or on the light-shielding layer in the unexposed area. .

(Photoinitiator)
The said coloring composition may contain a photoinitiator as needed. Thereby, radiation sensitivity can be imparted to the coloring composition. The photopolymerization initiator is a compound that generates active species capable of initiating polymerization of the cross-linking agent upon exposure to radiation such as visible light, ultraviolet rays, far infrared rays, electron beams, and X-rays.

Examples of the photopolymerization initiator include thioxanthone-based compounds, acetophenone-based compounds, biimidazole-based compounds, triazine-based compounds, O-acyloxime-based compounds, onium salt-based compounds, benzoin-based compounds, benzophenone-based compounds, and α-diketones. type compounds, polynuclear quinone-based compounds, diazo-based compounds, imidosulfonate-based compounds, aminoketone-based compounds, and the like. A photoinitiator can be used individually or in mixture of 2 or more types.

In the coloring composition of the present invention, the content of the photopolymerization initiator is preferably 0.01 to 120 parts by mass, particularly preferably 1 to 100 parts by mass, relative to 100 parts by mass of the cross-linking agent. In this case, if the content of the photopolymerization initiator is too low, curing by exposure may be insufficient.

(dispersion medium)
The coloring composition contains a dispersing medium. The dispersion medium can be appropriately selected and used as long as it disperses or dissolves other components constituting the coloring composition, does not react with these components, and has moderate volatility. For example, conventionally known organic solvents can be used, and examples thereof include organic solvents (dispersion media) that can be used in the dispersant composition. The organic solvent is preferably glycol alkyl ether acetates, monohydric or polyhydric alcohols, from the viewpoint of dispersibility of pigments, solubility of dispersants, applicability of pigment dispersion compositions, and the like. The solvent contained in the pigment dispersion composition may be of one kind or may be of a plurality of kinds.

When the pixels of the color filter are formed by photolithography, the boiling point of the dispersion medium (under a pressure of 1013.25 hPa; hereinafter, all boiling points are the same) is preferably 100°C to 200°C. Among the above dispersion media, glycol alkyl ether acetates are preferred because they have a good balance of applicability, surface tension, etc., and relatively high solubility of the constituent components in the coloring composition. It is also preferable to use a dispersion medium having a boiling point of 150° C. or higher. By using a dispersion medium with a high boiling point, it is possible to suppress the destruction of the interrelationships of the coloring composition due to rapid drying of the coloring composition. The dispersion medium having a boiling point of 150° C. or higher may be glycol alkyl ether acetates. The content of the dispersion medium having a boiling point of 150° C. or higher is preferably 3 to 50% by mass in 100% by mass of the entire dispersion medium.

The content of the dispersion medium in the coloring composition is not particularly limited and can be adjusted as appropriate. The upper limit of the content of the dispersing medium in the coloring composition is usually 99% by mass. In addition, the lower limit of the content of the dispersion medium in the coloring composition is usually 70% by mass, preferably 80% by mass, in consideration of the viscosity suitable for application of the coloring composition. The dispersion medium can be used as a solvent for dissolving and removing precipitates formed from the coloring composition.

(Other compounding agents)
In addition to the above-described compounding agents, other compounding agents can be blended into the coloring composition as long as they do not impair the preferred physical properties of the present invention. Other compounding agents include sensitizing dyes, thermal polymerization inhibitors, nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, plasticizers, organic carboxylic acid compounds, organic carboxylic acid compounds, Acid anhydrides, pH adjusters, antioxidants, UV absorbers, light stabilizers, preservatives, antifungal agents, surfactants, anti-aggregating agents, adhesion improvers, development improvers, storage stabilizers, etc. be able to.

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, 2,5-bis(p-diethylaminophenyl)1,3,4-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. is mentioned.

Thermal polymerization inhibitors include hydroquinone, p-methoxyphenol, pyrogallol, catechol, 2,6-t-butyl-p-cresol, β-naphthol and the like.

Nonionic surfactants include fluorine-based surfactants, silicone-based surfactants, polyoxyethylene-based surfactants, and the like.
Examples of anionic surfactants include alkylsulfonates, alkylbenzenesulfonates, alkylnaphthalenesulfonates, polyoxyethylene alkylethersulfonates, alkylsulfates, alkylsulfates, higher alcohol sulfates, aliphatic Alcohol sulfates, polyoxyethylene alkyl ether sulfates, polyoxyethylene alkylphenyl ether sulfates, alkyl phosphates, polyoxyethylene alkyl ether phosphates, polyoxyethylene alkylphenyl ether phosphates, special polymer surfactants agents and the like.
Cationic surfactants include quaternary ammonium salts, imidazoline derivatives, alkylamine salts and the like.
Amphoteric surfactants include betaine type compounds, imidazolium salts, imidazolines, amino acids and the like.

Examples of plasticizers include dioctyl phthalate, didodecyl phthalate, triethylene glycol dicaprylate, dimethyl glycol phthalate, tricresyl phosphate, dioctyl adipate, dibutyl sebacate, triacetyl glycerin and the like.

Examples of organic carboxylic acid compounds include monocarboxylic acids, carboxylic acids in which a carboxy group is directly bonded to a phenyl group, and carboxylic acids in which a carboxy group is bonded to a phenyl group via a carbon bond.

Organic carboxylic anhydrides include acetic anhydride, trichloroacetic anhydride, trifluoroacetic anhydride, tetrahydrophthalic anhydride, succinic anhydride, maleic anhydride, citraconic anhydride, itaconic anhydride, glutaric anhydride, 1,2- cyclohexenedicarboxylic acid, n-octadecylsuccinic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, naphthalic anhydride and the like.

<Method for producing colored composition>
The coloring composition can be prepared by mixing a coloring agent, a dispersant composition, a binder resin, a dispersion medium, and, if necessary, a cross-linking agent, a photopolymerization initiator, and other compounding agents. For mixing, for example, a mixing and dispersing machine such as a paint shaker, bead mill, ball mill, dissolver or kneader can be used. The coloring composition is preferably filtered after mixing. Since the coloring composition has alkali developability, it can be suitably used for a color filter.

Also, the coloring material may be surface-treated in advance with the dispersant composition of the present invention. Surface treatment methods include a dry method in which a dispersant is added and mixed while stirring the coloring material using a Henschel mixer, ball mill, atomizer colloid mill, Banbury mixer, etc., and a wet method in which the solvent is removed after treatment in a solvent. can be used. By performing the surface treatment with the dispersant composition of the present invention in this manner, the dispersibility of the colorant can be improved and aggregation can be prevented.

<Color filter>
The color filter of the present invention comprises a colored layer formed using the coloring composition.

Examples of methods for manufacturing color filters include the following methods. First, thermoplastic resin sheets such as polyester resins, polyolefin resins, polycarbonate resins, and polymethyl methacrylate resins; thermosetting resin sheets such as epoxy resins, unsaturated polyester resins, and poly(meth)acrylic resins; various types of glass, etc. on a transparent substrate, color pixels that transmit light of the three primary colors of red (R), green (G) and blue (B), preferably comprising a black matrix formed from the coloring composition is. As a method for producing a color filter, a black colored composition is applied and then pre-baked to evaporate the solvent (dispersion medium) to form a coating film. Next, after exposing this coating film through a photomask, it is developed using an alkaline developer (such as an aqueous solution containing an organic solvent or a surfactant and an alkaline compound) to dissolve and remove the unexposed areas of the coating film. to form a black pattern (black matrix). Then, after post-baking if necessary, the same operation is sequentially repeated for red (R), green (G) and blue (B), so that a pixel array of three primary colors of red, green and blue is arranged on the substrate. A colored filter is obtained. However, in the present invention, the order of forming pixels of each color is not limited to the above.

When the coloring composition is applied to the substrate, an appropriate coating method such as a spray method, a roll coating method, a spin coating method (spin coating method), a slit die coating method, a bar coating method, or the like can be employed. In particular, it is preferable to employ a spin coating method or a slit die coating method.

After forming a protective film on the thus obtained pixel pattern as necessary, a transparent conductive film (indium tin oxide (ITO) or the like) is formed by sputtering. After forming the transparent conductive film, a spacer may be further formed to form a color filter.

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

In addition, since the coloring composition has a low viscosity and an excellent dispersibility of the coloring material, it is suitable as a coloring column spacer to be supported on a thin film transistor (TFT) substrate and a color filter substrate positioned with a liquid crystal layer interposed therebetween. can be used for For example, there is a high optical density (OD) composition described in JP-A-2015-191234.

Hereinafter, the present invention will be described in more detail based on specific examples. The present invention is by no means limited to the following examples, and can be modified as appropriate without changing the gist of the invention. The polymerization rate, weight average molecular weight (Mw), molecular weight distribution (PDI) and amine value of the block copolymer and binder resin, the amount of formaldehyde in the dispersant composition, and the dispersibility (viscosity) of the coloring composition are as follows. was evaluated according to the method of

Abbreviations have the following meanings.
BA: butyl acrylate BMA: butyl methacrylate PCL5: 5 mol caprolactone adduct of 2-hydroxyethyl methacrylate (manufactured by Daicel Chemical Industries, Ltd., Plaxel (registered trademark) FM5)
PCL FA5: 5 mol caprolactone adduct of 2-hydroxyethyl acrylate (manufactured by Daicel Chemical Industries, Ltd., Plaxel (registered trademark) FA5)
DMAEMA: dimethylaminoethyl methacrylate DMAAm: dimethylacrylamide BTEE: ethyl-2-methyl-2-n-butyltheranyl-propionate DBDT: dibutyl ditelluride AIBN: 2,2'-azobis(isobutyronitrile)
PMA: propylene glycol monomethyl ether acetate

(Polymerization rate)
¹ H-NMR was measured (solvent: CDCl ₃ , internal standard: TMS) using a nuclear magnetic resonance (NMR) spectrometer (manufactured by Bruker Biospin, model: AVANCE500 (frequency: 500 MHz)). With respect to the obtained NMR spectrum, the integration ratio of the peaks of the monomer-derived vinyl group and the polymer-derived ester side chain peak was determined to calculate the polymerization rate of the monomer.

(Weight average molecular weight (Mw) and molecular weight distribution (PDI))
It was determined by gel permeation chromatography (GPC) using a high-performance liquid chromatograph (manufactured by Tosoh, model HLC-8320). One column SHODEX KF-603 (φ6 mm × 150 mm) (manufactured by SHODEX), 10 mmol / L lithium bromide / 10 mmol / L acetic acid / N-methyl-2-pyrrolidone solution in the mobile phase, differential refractometer in the detector It was used. The measurement conditions were a column temperature of 40° C., a sample concentration of 20 mg/mL, a sample injection amount of 10 μm, and a flow rate of 0.2 mL/min. Polystyrene (molecular weight 427,000, 190,000, 96,400, 37,400, 10,200, 2,630, 906) is used as a standard substance to create a calibration curve (calibration curve), and the weight average molecular weight ( Mw) and number average molecular weight (Mn) were measured. A molecular weight distribution (PDI=Mw/Mn) was calculated from this measured value.

(amine value)
The amine number represents the mass of potassium hydroxide (KOH) equivalent to the basic component per gram of solid content. A measurement sample was dissolved in tetrahydrofuran, and the resulting solution was neutralized and titrated with a 0.1 mol/L hydrochloric acid/2-propanol solution using a potentiometric titrator (trade name: GT-06, manufactured by Mitsubishi Chemical Corporation). Using the inflection point of the titration pH curve as the titration end point, the amine value (B) was calculated by the following formula.
B = 56.11 x Vs x 0.1 x f/w
B: amine value (mgKOH/g)
Vs: Amount (mL) of 0.1 mol/L hydrochloric acid/2-propanol solution required for titration
f: 0.1 mol/L hydrochloric acid (2-propanolic) titer w: Mass (g) of measurement sample (in terms of solid content)

(viscosity)
Using an E-type viscometer (trade name: TVE-22L, manufactured by Toki Sangyo Co., Ltd.) and using a cone rotor (1°34′×R24), the viscosity was measured at 25° C. and a rotor speed of 60 rpm. The measurement was performed on the colored composition stored at 25°C for 2 hours after preparation.

(Formaldehyde amount)
0.5 g of the dispersant composition was added to a cartridge filled with silica gel impregnated with DNPH (2,4-dinitrophenylhydrazine) (Sep Pak (registered trademark) DNPH Silica Plus Cartridge (product number: WAT037500) manufactured by Waters). Injected and allowed to stand at room temperature for 2 hours.
It was washed out with 4 mL of acetonitrile and diluted to 5 mL. Liquid chromatograph (manufactured by Shimadzu Corporation, trade name: LC-10AD, column: Pro C18 RS (4.6 × 250 mm, 5 μm (manufactured by YMC), mobile phase: acetonitrile / ultrapure water = 65:35 solution, column temperature : 40 ° C., flow rate: 1.0 mL / min, detection wavelength: 360 nm), using two types of aldehyde-DNPH mixed standard solution (0.1 μg aldehyde / μL acetonitrile, manufactured by Wako Pure Chemical Industries) as a standard substance, measurement The amount of formaldehyde was calculated from the measurement results.

<Production of block copolymer>
(Block copolymer No. 1)
PCL FA5 (135.0 g), BA (20.5 g), AIBN (0.82 g), and PMA (103.6 g) were charged into a flask equipped with an argon gas inlet tube and a stirrer, and after argon substitution, BTEE (7 .49 g) was added and reacted at 60° C. for 21 hours. The polymerization rate was 97.6%.

A mixed solution of DMAAm (51.1 g) and PMA (34.1 g) previously substituted with argon and AIBN (0.41 g) were added to the obtained solution, and the mixture was reacted at 60° C. for 13 hours. The polymerization rate was 100%.

After completion of the reaction, the reaction solution was poured into stirring n-heptane. Block copolymer No. 1 was obtained by filtering the precipitated polymer with suction and drying it. got 1. Obtained block copolymer no. 1 had a Mw of 14,614, a PDI of 1.42 and an amine number of 0 mg KOH/g. In addition, Table 2 shows the block copolymer No. 1 was shown. The content of each structural unit in the copolymer was calculated from the charging ratio and polymerization rate of the monomers used in the polymerization reaction.

(Block copolymer No. 2)
PCL5 (275.8 g), BMA (45.3 g), AIBN (1.64 g), and PMA (90.3 g) were charged into a flask equipped with an argon gas inlet tube and a stirrer, and after purging with argon, BTEE (14. 99 g) and DBDT (18.47 g) were added and reacted at 60° C. for 10 hours. The polymerization rate was 99.6%.

A mixed solution of DMAEMA (162.6 g) and PMA (40.6 g) previously substituted with argon was added to the obtained solution and reacted at 60° C. for 11 hours. The polymerization rate was 98.1%.

After completion of the reaction, the reaction solution was poured into n-heptane with stirring. Block copolymer No. 1 was obtained by filtering the precipitated polymer with suction and drying it. got 2. Obtained block copolymer no. 2 had a Mw of 14,797, a PDI of 1.44 and an amine value of 118 mg KOH/g. Also, Table 2 shows the block copolymer No. 2 was shown. The content of each structural unit in the copolymer was calculated from the charging ratio and polymerization rate of the monomers used in the polymerization reaction.

<Dispersant composition>
0.325 g of each block copolymer was dissolved in 0.675 g of PMA to prepare a dispersant composition. The amount of formaldehyde for this dispersant composition was measured and shown in Table 2.

Dispersant Composition No. In No. 2, the B block of the block copolymer which is the dispersant does not have the structural unit of general formula (1), but has a structural unit derived from dimethylaminoethyl methacrylate. This dispersant composition no. 2 had a high formaldehyde content of 1.7 ppm. On the other hand, dispersant composition No. In No. 1, the B block of the block copolymer which is the dispersant has the structural unit of general formula (1). This dispersant composition no. 1 had a formaldehyde content of 0.1 ppm, which was significantly reduced.

<Synthesis of alkali-soluble resin (binder resin)>
An argon gas inlet tube and a flask equipped with a stirrer were charged with methacrylic acid (MAA) (40.0 g), benzyl methacrylate (BzMA) (160.0 g) and propylene glycol monomethyl ether acetate (PMA) (580.0 g), After purging with argon, 2,2'-azobis(isobutyronitrile) (AIBN) (4.0 g), n-dodecanethiol (6.0 g) and PMA (20.0 g) were added and the temperature was raised to 90°C. While maintaining the solution at 90 ° C., add MAA (80.0 g), BzMA (320.0 g), AIBN (8.0 g), n-dodecanethiol (12.0 g), PMA (50.0 g) to the solution. It was added dropwise over 1.5 hours. 60 minutes after the completion of dropping, the temperature was raised to 110° C., AIBN (0.8 g) and PMA (10.0 g) were added and allowed to react for 1 hour, and further AIBN (0.8 g) and PMA ( 10.0 g) was added and allowed to react for 1 hour, then AIBN (0.8 g) and PMA (10.0 g) were added and allowed to react for 1 hour.

The resulting reaction solution was cooled to room temperature, PMA (240.0 g) was added, and an alkali-soluble resin solution having a non-volatile content of 39.5% was obtained. The weight average molecular weight (Mw) of the alkali-soluble resin was 9,150, the molecular weight distribution (PDI) was 1.92, and the acid value was 128 mgKOH/g.

<Preparation of coloring composition>
Coloring composition no. 1-1, 1-2
8 parts by mass of pigment, block copolymer No. 1 6 parts by mass, 6 parts by mass of alkali-soluble resin, and 80 parts by mass of PMA. ) for 3 hours to fully disperse. After completion of dispersion, the beads were separated by filtration to obtain a colored composition. C.I. I. Pigment Red 254 (trade name: BKCF, manufactured by Ciba Specialty Chemicals) or C.I. I. Pigment Green 58 (trade name: FASTOGEN (registered trademark) GREEN A310, manufactured by DIC) was used, and colored composition No. 1-1 (red composition) and colored composition No. 1-2 (green composition) was prepared. When the dispersibility of the obtained red composition and green composition was evaluated, the viscosity of each composition was 30 mPa·s or less.

Coloring composition no. 2-1, 2-2
Colored composition No. 1 except that the block copolymer was changed. Coloring composition No. 1 was prepared in the same manner as in the preparation methods of 1-1 and 1-2. 2-1 (red composition) and colored composition No. 2-2 (green composition) was prepared. When the dispersibility of the obtained red composition and green composition was evaluated, the viscosity of each composition was 30 mPa·s or less.

Coloring composition no. 1-1 and 1-2 both have viscosities of 30 mPa·s or less. Similar to 2-1 and 2-2, the dispersibility of the pigment is good. Therefore, it can be understood that a block copolymer in which the B block has the structural unit of general formula (1) can be used as a dispersant, although it does not have an amino group or a quaternary ammonium base. Therefore, by using a block copolymer in which the B block has the structural unit of general formula (1), it is possible to reduce the amount of formaldehyde and obtain a coloring composition having excellent pigment dispersibility. It is understood that

The present invention includes the following embodiments.
(Embodiment 1)
A dispersant composition comprising a polymer having a structural unit represented by formula (1).

［一般式（１）において、Ｒ¹¹は水素原子または置換基を有していてもよい鎖状もしくは環状の炭化水素基を表す。Ｒ¹²は置換基を有していてもよい鎖状もしくは環状の炭化水素基を表す。Ｒ¹¹およびＲ¹²が互いに結合して環状構造を形成していてもよい。Ｒ¹³は水素原子またはメチル基を表す。］

[In general formula (1), R ¹¹ represents a hydrogen atom or a chain or cyclic hydrocarbon group which may have a substituent. R ¹² represents a chain or cyclic hydrocarbon group which may have a substituent. R ¹¹ and R ¹² may combine with each other to form a cyclic structure. ^R13 represents a hydrogen atom or a methyl group. ]

(Embodiment 2)
A dispersant composition according to aspect 1, wherein the polymer has an amine value of less than 10 mg KOH/g.

(Embodiment 3)
Aspect 1 or 2 wherein the polymer is a block copolymer having an A block having a structural unit derived from a (meth)acrylic monomer and a B block having a structural unit represented by the general formula (1). The dispersant composition according to .

(Embodiment 4)
The dispersant composition according to aspect 3, wherein the A block has a structural unit represented by general formula (10).

［一般式（１０）において、ｎ１は１～１０の整数を表す。Ｒ¹は水素原子またはメチル基を表す。Ｒ²は炭素数が１～１０のアルキレン基を表す。Ｒ³は炭素数が１～１０のアルキレン基を表す。］

[In the general formula (10), n1 represents an integer of 1 to 10. R ¹ represents a hydrogen atom or a methyl group. R ² represents an alkylene group having 1 to 10 carbon atoms. R ³ represents an alkylene group having 1 to 10 carbon atoms. ]

(Embodiment 5)
5. The dispersant composition according to aspect 3 or 4, wherein the mass ratio of A block to B block (A block/B block) in the block copolymer is 50/50 or more.

(Embodiment 6)
The dispersant composition according to any one of aspects 3 to 5, wherein the block copolymer has a molecular weight distribution (PDI) of 2.5 or less.

(Embodiment 7)
The dispersant composition according to any one of aspects 3 to 6, wherein the block copolymer is polymerized by living radical polymerization.

(Embodiment 8)
A coloring composition comprising the dispersant composition according to any one of aspects 1 to 7, a coloring material, a binder resin and a dispersion medium.

(Embodiment 9)
The coloring composition according to aspect 8, which is for a color filter.

(Embodiment 10)
A color filter comprising a colored layer formed using the colored composition according to aspect 9.

Claims (8)

Having an A block containing a structural unit represented by general formula (10) and a B block containing a structural unit represented by general formula (1),
The content of the structural unit represented by the general formula (10) in 100% by mass of the A block is 10% by mass or more, and the content of the structural unit represented by the general formula (1) is less than 5% by mass,
The content of the structural unit represented by the general formula (1) in 100% by mass of the B block is 80% by mass or more,
The mass ratio of A block to B block (A block/B block) is 50/50 to 95/5,
A dispersant composition comprising a block copolymer having an amine value of less than 10 mgKOH/g .

[In general formula (1), R ¹¹ represents a hydrogen atom , a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, or a cyclic alkyl group having 6 to 12 carbon atoms. show.
R ¹² represents a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, or a cyclic alkyl group having 6 to 12 carbon atoms.
R ¹¹ and R ¹² may combine with each other to form a cyclic structure represented by general formula (1-1), (1-2) or (1-3) .
^R13 represents a hydrogen atom or a methyl group. ]

[In general formulas (1-1), (1-2) and (1-3), R ¹⁴ represents an alkyl group having 1 to 6 carbon atoms. l represents an integer of 0 to 5; m represents an integer of 0 to 4; n represents an integer of 0 to 4; * represents a bond. When l is 2 to 5, m is 2 to 4, and n is 2 to 4, a plurality of R ¹⁴ may be the same or different. ]

[In the general formula (10), n1 represents an integer of 1 to 10. R ¹ represents a hydrogen atom or a methyl group. R ² represents an alkylene group having 1 to 10 carbon atoms. R ³ represents an alkylene group having 1 to 10 carbon atoms. ] 2. The dispersion according to claim 1, wherein the content of structural units derived from a vinyl monomer having an amino group (including those in which the amino group is quaternized) in the block copolymer is 2% by mass or less. agent composition. 3. The dispersant composition according to claim 1, wherein the block copolymer has a weight average molecular weight of 3,000 to 40,000 . The dispersant composition according to any one of claims 1 to 3 , wherein the block copolymer has a molecular weight distribution (PDI) of 2.5 or less. The dispersant composition according to any one of claims 1 to 4, wherein the block copolymer is polymerized by living radical polymerization. A coloring composition comprising the dispersant composition according to any one of claims 1 to 5 , a coloring material, a binder resin and a dispersion medium. The coloring composition according to claim 6, which is for color filters. A color filter comprising a colored layer formed using the colored composition according to claim 7 .