KR20200137989A - Pigment dispersion composition for color filter and pigment dispersion resist composition for color filter - Google Patents

Abstract

In the present invention, when a pigment dispersion resist composition for color filters is prepared based on the pigment dispersion composition for color filters, the low viscosity of the pigment dispersion resist composition for color filters, viscosity stability, PGMEA resolubility, alkali developer solubility (potassium hydroxide The improvement in aqueous solution solubility, TMAH aqueous solution solubility) and heat resistance, and furthermore, no developing residue is a problem.
In order to solve the above problems, the pigment dispersion composition for a color filter of the present invention is a pigment dispersion composition for a color filter containing a coloring pigment, a pigment dispersant, an alkali-soluble resin and an organic solvent, wherein the pigment dispersant comprises an amino group and/or a pyridine ring. The acrylic block polymer to be contained is contained, and the alkali-soluble resin contains the block polymer.

Description

Pigment dispersion composition for color filter and pigment dispersion resist composition for color filter {Pigment dispersion composition for color filter and pigment dispersion resist composition for color filter}

The present invention relates to a pigment dispersion composition for a color filter and a pigment dispersion resist composition for a color filter.

BACKGROUND ART In recent years, the development of color filters for high color reproduction has been advanced, and with this, the required performance of the pigment dispersion composition for color filters and the pigment dispersion resist composition for color filters is also becoming strict. Not only the quality of the final product, the color filter, but also the pigment dispersion composition in the resist is included in a large amount, and the demand for the process surface is also becoming more demanding.

In particular, it is difficult to achieve both the contradicting performance of improving the resolubility in propylene glycol monomethyl ether acetate (PGMEA) and improving the solubility in an alkaline developer.

Japanese Patent Publication No. 2017-142475

The problem to be solved by the present invention is that when a pigment dispersion resist composition for color filters is prepared based on the pigment dispersion composition for color filters, the low viscosity of the pigment dispersion resist composition for color filters, viscosity stability, PGMEA resolubility, alkali developer solubility (Solubility in aqueous solution of potassium hydroxide, solubility in aqueous solution of tetramethylammonium hydroxide (TMAH)) and heat resistance are improved, and furthermore, there is no development residue.

In order to solve the above problems, in the present invention, a pigment dispersant and an alkali-soluble resin contained in the pigment dispersion composition for color filters were examined.

Accordingly, the present invention consists of the following composition.

1. A pigment dispersion composition for color filters containing a coloring pigment, a pigment dispersant, an alkali-soluble resin, and an organic solvent, wherein the pigment dispersant contains an acrylic block polymer containing an amino group and/or a pyridine ring, and the alkali-soluble resin A pigment dispersion composition for color filters containing a block polymer.

2. The pigment dispersion composition for color filters described in 1 containing a photopolymerizable compound.

3. The pigment dispersion composition for color filters according to 1 or 2, containing 1 to 200 mass% of an alkali-soluble resin of a block polymer with respect to the coloring pigment.

4. The pigment dispersion composition for color filters according to any one of 1 to 3, wherein a pigment dispersant of an acrylic block polymer and/or an alkali-soluble resin of a block polymer is synthesized by living polymerization.

5. The pigment dispersion composition for color filters according to any one of 1 to 4, wherein the amine contained in the pigment dispersant of the acrylic block polymer is a tertiary amine or a quaternary amine.

6. The pigment dispersion composition for color filters according to any one of 1 to 5, wherein the alkali-soluble resin of the block polymer is localized in the molecule of the block polymer.

7. The pigment dispersion composition for color filters according to any one of 1 to 6, wherein the amine moiety is localized in the molecule of the block polymer in the pigment dispersant of the acrylic block polymer.

8. The pigment dispersion composition for color filters according to any one of 1 to 7, wherein the acid value of the alkali-soluble resin of the block polymer is 5 to 250 mgKOH/g.

9. The pigment dispersion composition for color filters according to any one of 1 to 8, wherein the amine value of the pigment dispersant of the acrylic block polymer is 40 to 200 mgKOH/g.

10. The pigment dispersion resist composition for color filters containing the pigment dispersion composition for color filters in any one of 1-9.

According to the present invention, when the pigment dispersion resist composition for color filters is prepared based on the pigment dispersion composition for color filters, the viscosity of the pigment dispersion resist composition for color filters is reduced, viscosity stability, PGMEA resolubility, alkali developer solubility ( Potassium hydroxide aqueous solution solubility, TMAH aqueous solution solubility) and heat resistance improvement, and furthermore, it became possible to have no developing residue.

The pigment dispersion composition for color filters and the pigment dispersion resist composition for color filters of the present invention will be described in detail below.

The present invention mainly relates to a pigment dispersion composition for a color filter for a display device and a pigment dispersion resist composition for a color filter. The pigment dispersion composition for a color filter may be a composition other than a resist.

Either way, the pigment dispersion composition for color filters and the pigment dispersion resist composition for color filters of the present invention are mainly used when preparing the pigment dispersion resist composition for color filters of a display device. It is possible to improve painting, viscosity stability, PGMEA re-solubility, alkali developer solubility (potassium hydroxide aqueous solution solubility, TMAH aqueous solution solubility) and heat resistance, and furthermore, no development residue.

In the case where the viscosity cannot be reduced as a composition such as a resist, there is a possibility that the application process becomes complicated or difficult application conditions.

If PGMEA re-solubility is not excellent, there is a possibility that a dry film may occur after applying the resist solution with a coater, and if it is not easily re-dissolved with TMAH or PGMEA, the dried film may become a foreign substance during subsequent treatment. In the case where the alkali developer solubility is not excellent, that is, the solubility of the coating film in the alkali developer is low, or the coating film is peeled off without dissolving, there is a possibility that patterning excellent in linearity during alkaline development may become difficult. In addition, when it has a developing residue, an additional process is required to dissolve the residue.

The present invention is a pigment dispersion resist composition for color filters obtained by blending a pigment dispersion composition for color filters and an alkali-soluble resin or a photopolymerizable compound to the pigment dispersion composition for color filters.

In addition, the pigment dispersion composition for a color filter includes a photo-curable type and one that is not.

[A. Composition of pigment dispersion composition for color filter]

The pigment dispersion composition for a color filter of the present invention is mainly composed of a coloring pigment, a pigment dispersant, an alkali-soluble resin and an organic solvent, and contains a block polymer as a pigment dispersant and an alkali-soluble resin.

(Colored pigment)

As the coloring pigments that can be used, various pigments such as blue pigments, green pigments, red pigments, yellow pigments, purple pigments, orange pigments, and brown pigments. In addition, in addition to organic pigments such as azo-based, phthalocyanine-based, quinacridone-based, benzimidazolone-based, isoindolinone-based, dioxazine-based, indanthrene-based, and perylene-based organic pigments, barium sulfate, lead sulfate, titanium oxide, and yellow Inorganic pigments such as lead, bengala, and chromium oxide can also be used.

Examples of these pigments are as follows.

As a red pigment, CI pigment red 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 14, 15, 16, 17, 21, 22, 23, 31, 32, 37, 38, 41, 47, 48, 48: 1, 48: 2, 48: 3, 48: 4, 49, 49: 1, 49: 2, 50: 1, 52: 1, 52: 2, 53, 53: 1, 53: 2, 53: 3, 57, 57: 1, 57: 2, 58: 4, 60, 63, 63: 1, 63: 2, 64, 64: 1, 68, 69, 81, 81: 1, 81: 2, 81: 3, 81: 4, 83, 88, 90: 1, 97, 101, 101: 1, 104, 108, 108: 1, 109, 112, 113, 114, 122, 123, 144, 146, 147, 149, 151, 166, 168, 169, 170, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 184, 185, 187, 188, 190, 192, 193, 194, 200, 202, 206, 207, 208, 209, 210, 214, 215, 216, 217, 220, 221, 223, 224, 226, 227, 228, 230, 231, 232, 233, 235, 236, 237, 238, 239, 240, 242, 243, 245, 247, 249, 250, 251, 253, 254, 255, 256, 257, 258, 259, 260, 262, 263, 264, 265, 266, 267, It is one or more of 268, 269, 270, 271, 272, 273, 274, 275, 276.

As a blue pigment, CI Pigment Blue 1, 1:2, 9, 14, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 17, 19, 22, 25, 27, 28, 29, 33, 35, 36, 56, 56:1, 60, 61, 61:1, 62, 63, 64, 66, 67, 68, 71, 72, 73, 74, 75, 76, 78 and 79 are mentioned. Among them, preferably one or more of C. I. Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, and 15:6.

As a green pigment, one of CI Pigment Green 1, 2, 4, 7, 8, 10, 13, 14, 15, 17, 18, 19, 26, 36, 45, 48, 50, 51, 54, 55 That's it.

As a yellow pigment, CI pigment yellow 1:1, 2, 3, 4, 5, 6, 9, 10, 12, 13, 14, 16, 17, 20, 24, 31, 32, 34, 35, 35:1, 36, 36:1, 37, 37:1, 40, 41, 42, 43, 48, 53, 55, 61, 62, 62:1, 63, 65, 73, 74, 75, 81, 83, 86, 87, 93, 94, 95, 97, 100, 101, 104, 105, 108, 109, 110, 111, 116, 117, 119, 120, 125, 126, 127, 127: 1, 128, 129, 133, 134, 136, 137, 138, 139, 142, 147, 148, 150, 151, 153, 154, 155, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 172, 173, 174, 175, 176, 180, 181, 182, 183, 184, 185, 188, 189, 190, 191, 191: 1, 192, 193, 194, 195, 196, 197, 198, 199, 200, 202, 203, 204, 205, 206, 207, 208.

As an orange pigment, CI pigment orange 1, 2, 5, 13, 16, 17, 19, 20, 21, 22, 23, 24, 34, 36, 38, 39, 43, 46, 48, 49, 51, 55, 59, 61, 62, 64, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 77, 78, 79.

As a purple pigment, CI pigment violet 1, 1:1, 2, 2:2, 3, 3:1, 3:3, 5, 5:1, 14, 15, 16, 19, 23, 25, 27, 29, 30, 31, 32, 37, 39, 40, 42, 44, 47, 49, 50.

In order to impart high brightness and contrast to the pigment dispersion composition for color filters of the present invention, it is preferable to use a pigment subjected to micronization treatment as the respective coloring pigments. By performing micronization treatment, the primary particle diameter of the colored pigment can be made finer and more uniform.

Examples of the micronization treatment include untreated colored pigments, water-soluble inorganic salts (sodium chloride, barium chloride, potassium chloride, etc., preferably sodium chloride, and the average particle diameter of the water-soluble inorganic salt used is preferably 50 µm or less), and the above Mixtures containing water-soluble dispersion media (alkoxy alcohols, glycols, ethers, etc.) that do not substantially dissolve water-soluble inorganic salts are kneaded, roll mills, ball mills, art writers, sand mills, Japanese Patent Laid-Open No. 2006-192385 After kneading with a kneading device such as Trimix (trade name) manufactured by Inoue Co., Ltd., a planetary mixer described in the publication, and Miracle KCK (trade name) manufactured by Asada Iron Works Co., Ltd., a continuous uniaxial kneader, the water-soluble It is preferable to perform a micronization treatment by performing salt milling to remove the inorganic salt and the water-soluble dispersion medium.

In addition, since the crystal growth of the colored pigment can be suppressed and refined uniformly, it is preferable to perform micronization treatment in the presence of a pigment dispersion aid to be described later. The amount of the pigment dispersion aid used at this time is 0.5 to 30 parts by mass, preferably 3 to 10 parts by mass, based on 100 parts by mass of the colored pigment.

(Pigment dispersion aid)

As a pigment dispersion aid that may be used in the pigment dispersion composition for a color filter of the present invention, an acid group that enhances affinity with an organic solvent is introduced into a basic skeleton having the same or similar molecular structure as the molecular structure of the pigment to be used. What is used as a pigment dispersion aid having a is suitable. Such pigment dispersion aids are finer during pigment dispersion or disperse over time after dispersion by increasing the affinity of the acid group with the organic solvent or pigment dispersant by adsorbing the part of the basic skeleton to the pigment surface in the process of micronizing or dispersing the pigment. It has an effect of improving stability and the like. Further, it is more preferable that the pigment dispersion aid itself is dissolved in an organic solvent or dispersed as fine particles because it can be adsorbed over a wider range of the pigment surface.

Among them, when a pigment dispersion aid or the like having a sulfonic acid group is used as the acid group, good results can be obtained.

In the pigment dispersion composition for color filters of the present invention, the amount of the pigment dispersion aid having an acidic group is 0.5 to 30 parts by mass per 100 parts by mass of the coloring pigment. When the content of the pigment dispersion aid having an acidic group is less than 0.5 parts by mass, the pigment dispersing effect is lowered, while when it exceeds 30 parts by mass, the pigment dispersing effect is not further improved.

The method of using the pigment dispersion aid having an acidic group is as follows, for example.

(1) In the case of using a colored pigment subjected to micronization treatment in the absence of a pigment dispersion aid having an acid group, 0.5 parts by mass of a pigment dispersion aid having an acid group are added to 100 parts by mass of the colored pigment when dispersing the micronized colored pigment. -30 parts by mass, preferably 3 to 15 parts by mass are used.

(2) In the case of using a colored pigment subjected to micronization treatment in the presence of a pigment dispersion aid having an acidic group, 0.5 to 30 parts by mass of a pigment dispersion aid, preferably 0.5 to 30 parts by mass, per 100 parts by mass of the colored pigment when the colored pigment is micronized. Preferably, 3 to 15 parts by mass are used, and 0 to 29.5 parts by mass, preferably 0 to 12 parts by mass of a pigment dispersion aid having an acidic group are used for 100 parts by mass of the colored pigment when dispersing the pigmented pigment. .

In addition, the sum of the amount of the pigment dispersion aid having an acid group used in the micronization treatment and the amount of the pigment dispersion aid having an acid group used in the pigment dispersion of the colored pigment subjected to micronization treatment is based on 100 parts by mass of the colored pigment. 0.5 to 30 parts by mass, preferably 3 to 15 parts by mass of the pigment dispersion aid having an acidic group is used.

More specifically, the case where a pigment dispersion aid having a sulfonic acid group is used as the pigment dispersion aid having an acid group will be described.

When dispersing CI Pigment Blue 15:6 as a blue pigment, a pigment having an anthraquinone skeleton having the same skeleton as CI Pigment Blue 15:6, which is an epsilon copper phthalocyanine pigment, and/or a sulfonate of the dye is used as a pigment dispersion aid. .

(Pigment dispersant)

A pigment dispersant is added to the pigment dispersion composition for color filters of the present invention. This pigment dispersant contains a block polymer and is an acrylic block polymer containing an amino group and/or a pyridine ring, which further contains an amine compound and/or a pyridine ring-containing compound as a monomer. A block containing this amine compound and/or a pyridine ring-containing compound as a monomer is localized as an amine moiety and/or a pyridine ring moiety in the molecule of the block polymer.

The amine value of the acrylic block polymer is preferably 40 to 200 mgKOH/g. In addition, in the present invention, the amine value represents the mass (mg) of potassium hydroxide, which is equivalent to the amount of hydrochloric acid required to neutralize 1 g of the solid content of the resin, and is a value measured by a method according to JIS K 7237 to be.

In the pigment dispersion composition for color filters of the present invention, when using the pigment dispersant as a block polymer, the amount used is preferably 1 to 100 parts by mass, more preferably 1 to 60 parts by mass per 100 parts by mass of the coloring pigment. If the content of the pigment dispersant is less than 1 part by mass, the pigment dispersing effect is lowered, the initial viscosity after preparation of the composition is increased, and the viscosity may increase significantly after storage, while when it exceeds 100 parts by mass, alkali There is a fear of a decrease in developability or the like.

The types of blocks constituting the acrylic block polymer containing the monomer as the amine compound may be two or three or more, and the following ones are mentioned.

At least one of them is a block containing a monomer having a radically polymerizable unsaturated bond, which is an amine compound.

The monomer constituting this block is an amino group-containing monomer such as an acyclic amine compound, a heterocyclic amine compound, or a quaternary ammonium cation compound, such as dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth). Acyclic amine compounds such as acrylate, heterocyclic amine compounds such as pentamethylpiperidinyl (meth)acrylate, and compounds obtained by cationization by quaternizing dimethylaminopropyl (meth)acrylate with benzyl chloride, etc. As a monomer containing a quaternary ammonium cation compound and a pyridine ring, a compound such as vinylpyridine is preferable. A block made of one type of monomer among these monomers may be used, a block made by random polymerization of two or more monomers, or a block made by block polymerization of two or more monomers may be used.

As another polymerizable block copolymerized with a block derived from a monomer which is an amine compound, a block composed of one type of monomer may be used, or a block formed by random polymerization of two or more types of monomers may be used. It is preferable not to have a unit derived from a monomer containing an amino group or a pyridine ring. Moreover, it is more preferable not to have a carboxylic acid group, a hydroxyl group, a thiol group, or a group containing sulfur or phosphorus. Further, the number of blocks made of other polymerizable ethylenically unsaturated monomers may be one or two blocks.

Examples of these other polymerizable ethylenically unsaturated monomers include alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, and butyl (meth)acrylate, styrene, and 2-hydroxyethyl (meth)acrylic. Glycerol (meth)acrylates such as acrylate, allyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, and glycerol monoacrylate, N-phenylmaleimide, polystyrene macromonomer, polymethylmeth And one or more ethylenically unsaturated monomers selected from the group of monomers and oligomers such as acrylate macromonomer and carboepoxy diacrylate. However, it is preferable not to use N-vinylpyrrolidone or a sulfur element-containing monomer.

As the block copolymer, a block resin synthesized by living radical polymerization or anionic polymerization can be used.

In addition to the pigment dispersant which is a block polymer in the present invention, a conventional polymer pigment dispersant having a basic group conventionally used in the field of color filters can be used in combination. However, the content of the conventional polymer pigment dispersant is within a range that does not impair the effect of the present invention.

As a polymer pigment dispersant having such a basic group, the following are mentioned, for example.

(1) A polyester having an amino group and/or an imino group and a free carboxyl group of a polyamine compound (for example, poly(lower) alkyleneamine such as polyallylamine, polyvinylamine, polyethylene polyimine, etc.), At least one reaction product selected from the group consisting of polyamides and polyesteramides.

(2) A carbodiimide compound having one or more side chains selected from the group consisting of polyester side chains, polyether side chains, and polyacrylic side chains in the molecule, and at least one basic nitrogen-containing group.

(3) A reaction product of a low molecular weight amino compound such as poly(lower)alkyleneimine and methyliminobispropylamine, and a polyester having a free carboxyl group.

(4) In the isocyanate group of the polyisocyanate compound, an alcohol such as methoxypolyethylene glycol or a polyester having one hydroxyl group such as caprolactone polyester, a compound having 2 to 3 isocyanate group reactive functional groups, an isocyanate group reactive functional group A reaction product obtained by sequentially reacting an aliphatic or heterocyclic hydrocarbon compound having a tertiary amino group.

(5) A reaction product obtained by reacting a polyisocyanate compound and a hydrocarbon compound having an amino group with a polymerization product of an acrylate having an alcoholic hydroxyl group.

(6) A reaction product obtained by adding a polyether chain to a low molecular weight amino compound.

(7) A reaction product obtained by reacting a compound having an isocyanate group with a compound having an amino group.

(8) A reaction product obtained by reacting a polyepoxy compound with a linear polymer having a free carboxyl group and an organic amine compound having one secondary amino group.

(9) A reaction product of a polycarbonate compound and a polyamine compound having a functional group capable of reacting with an amino group at one end.

(10) Methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, stearyl methacrylate, benzyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, At least one selected from methacrylic acid esters or acrylic acid esters such as stearyl acrylate and benzyl acrylate, and acrylamide, methacrylamide, N-methylolamide, vinylimidazole, vinylpyridine, amino groups and polycapro A copolymer of at least one basic group-containing polymerizable monomer such as a monomer having a lactone skeleton, and at least one styrene, a styrene derivative, or another polymerizable monomer.

(11) An acrylic block copolymer composed of a block having a basic group such as a tertiary amino group or a quaternary ammonium base and a block not having a basic functional group.

(12) Pigment dispersant obtained by subjecting a polycarbonate compound to Michael addition reaction with polyallylamine.

(13) Carbodiimide compounds each having at least one polybutadiene chain and a basic nitrogen-containing group.

(14) Carbodiimide-based compounds each having at least one side chain having an amide group and one or more basic nitrogen-containing groups in the molecule.

(15) A polyurethane-based compound having a structural unit having an ethylene oxide chain and a propylene oxide chain, and having an amino group quaternized by a quaternizing agent.

(16) A compound obtained by reacting an isocyanate group of an isocyanate compound having an isocyanurate ring in the molecule, an active hydrogen group in the molecule, and an active hydrogen group of a compound having a carbazole ring and/or an azobenzene skeleton. Compounds in which the number of carbazole rings and azobenzene skeletons is 15% to 85% of the sum of urethane bonds and urea bonds generated by the reaction of isocyanate groups, isocyanate groups and active hydrogen groups derived from an isocyanate compound having an isocyanurate ring in the molecule Etc.

(Alkaline Soluble Resin)

An alkali-soluble resin is blended in the pigment dispersion composition for color filters of the present invention. As such a resin, it acts as a binder with respect to the pigment, and has solubility in a developer used in the developing process, particularly preferably an alkali developer, when producing a color filter.

As such an alkali-soluble resin, it is necessary to be a block copolymer. By employing a block copolymer, the pigment dispersibility is improved compared to other copolymers, and solubility in PGMEA or an alkaline developer can be imparted. When a random copolymer is used, the developer solubility of the pigment-dispersed resist composition deteriorates.

It is preferable to have a carboxyl group in the block copolymer.

Particularly, a block copolymer having a block composed of an ethylenically unsaturated monomer having one or more carboxyl groups, such as a block composed of (meth)acrylic acid or maleic acid, and a block composed of another copolymerizable ethylenically unsaturated monomer, is preferable. The types of blocks may be two or three. This block is an alkali-soluble site and is localized in the molecule of the copolymer as a block.

A block made of an ethylenically unsaturated monomer having one or more carboxyl groups may be a block made of one type of monomer, a block made by random polymerization of two or more monomers, or a block made by block polymerization of two or more monomers. It is preferably a block made of only methacrylic acid.

The block made of another polymerizable ethylenically unsaturated monomer may be a block made of one type of monomer, or a block made by random polymerization of two or more types of monomers. It is preferable not to have a unit derived from a monomer having a carboxyl group. Further, the number of blocks made of other polymerizable ethylenically unsaturated monomers may be one or two blocks.

Examples of these other polymerizable ethylenically unsaturated monomers include alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, and butyl (meth)acrylate, styrene, and 2-hydroxyethyl (meth)acrylic. Glycerol (meth)acrylates such as acrylate, allyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, and glycerol monoacrylate, N-phenylmaleimide, polystyrene macromonomer, polymethylmeth And one or more ethylenically unsaturated monomers selected from the group of monomers and oligomers such as acrylate macromonomer and carboepoxy diacrylate. However, it is preferable not to use N-vinylpyrrolidone or a sulfur element-containing monomer.

As the block copolymer, a block resin synthesized by living radical polymerization or anionic polymerization can be employed.

In addition, this alkali-soluble resin may have a photopolymerizable functional group.

The acid value of the alkali-soluble resin in the present invention is preferably 5 to 250 mgKOH/g, more preferably 10 to 200 mgKOH/g, and more preferably 60 to 150 mgKOH/g from the viewpoint of developing characteristics. g. In addition, in the present invention, the acid value is a theoretical acid value and is a value calculated arithmetically based on the ethylenically unsaturated monomer having a carboxyl group and its content.

In addition, the weight average molecular weight of the alkali-soluble resin in the present invention is usually preferably 1,000 to 100,000, more preferably 3,000 to 50,000, and still more preferably 7,000 to 20,000 in terms of developing properties and solubility in an organic solvent. . In the present invention, the weight average molecular weight of the alkali-soluble resin is a weight average molecular weight in terms of polystyrene obtained based on GPC. In the present invention, Water 2690 (manufactured by Waters Corporation) is used as an apparatus, and PLgel 5 µm MIXED-D (manufactured by Agilent Technologies Corporation) is used as a column.

The amount of the alkali-soluble resin used in the present invention is preferably 1 to 200 parts by mass, more preferably 10 to 150 parts by mass per 100 parts by mass of the colored pigment to be used. In this case, when the amount of the alkali-soluble resin used is less than 1 part by mass, there is a possibility that the developing characteristics may be deteriorated. On the other hand, if it exceeds 200 parts by mass, since the colorant concentration is relatively lowered, there is a fear that it becomes difficult to achieve the target color density as a thin film.

In addition, it is preferable that the alkali-soluble resin does not contain any amino group of primary, secondary and tertiary, and does not contain quaternary ammonium group. Moreover, it is more preferable not to have a basic group.

Further, an alkali-soluble resin having a structure other than the block copolymer may be blended within a range that does not impair the effects of the present invention.

(Other resin)

As the resin used in the pigment dispersion composition for a color filter of the present invention, a resin having a transmittance of 80% or more, preferably 95% or more in the entire wavelength range of 400 to 700 nm in the visible light region can be used. As these resins, thermosetting resins, thermoplastic resins, alkali-soluble resins, and the following photopolymerizable compounds can be used.

Such a resin is a mass fraction with respect to the total solid content of the pigment dispersion composition for color filters, preferably in the range of 5 to 94 mass%, more preferably 20 to 50 mass% in terms of the total amount of the resin to be used.

Examples of thermosetting resins and thermoplastic resins include butyral resins, styrene-maleic acid copolymers, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymers, polyvinyl acetate, polyurethane resins, and phenolic resins. , Polyester resin, acrylic resin, alkyd resin, styrene resin, polyamide resin, rubber resin, cyclized rubber, epoxy resin, cellulose, polybutadiene, polyimide resin, benzoguanamine resin, melamine resin, urea resin, etc. I can.

Further, in some cases, it is also possible to blend a photopolymerizable resin described later in the section of the pigment dispersion resist composition for color filters.

(Organic solvent)

As the organic solvent used in the pigment dispersion composition for color filters of the present invention, an organic solvent conventionally used in the field of liquid crystal color filter resists can be suitably used. Specifically, ester-based organic solvents, ether-based organic solvents, ether ester-based organic solvents, ketone-based organic solvents, aromatic hydrocarbon-based organic solvents, nitrogen-containing solvents having a boiling point of 100 to 220°C under normal pressure (1.013×10 ² kPa) Organic solvents, etc. When a large amount of an organic solvent having a boiling point exceeding 220°C is contained, when prebaking the pigment dispersion composition for color filters or the coating film formed by applying the composition containing the composition, the organic solvent is not sufficiently evaporated and It remains, and there exists a possibility that the heat resistance of a dry coating film may fall. In addition, when a large amount of the organic solvent having a boiling point of less than 100°C is contained, it becomes difficult to apply evenly and uniformly, and there is a fear that a coating film having excellent surface smoothness may not be obtained.

As the organic solvent used in the pigment dispersion composition for color filters of the present invention, specifically, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether , Diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, etc. Solvents; Ether ester organic solvents such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate; methyl isobutyl ketone, cyclo Ketone-based organic solvents such as hexanone, 2-heptanone, and δ-butyrolactone; 2-methyl hydroxypropionate, 2-ethyl hydroxypropionate, 2-hydroxy-2-ethyl ethylpropionate, 3-methyl-3 -Methoxybutyl propionate, 3-methyl methoxypropionate, 3-ethyl methoxypropionate, 3-methyl ethoxypropionate, 3-ethyl ethoxypropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, n-amyl formate Ester-based organic solvents such as; Alcohol-based solvents such as methanol, ethanol, isopropyl alcohol and butanol; Nitrogen-containing organics such as N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide Solvents etc. can be illustrated. These can be used alone or in combination of two or more.

Among these organic solvents, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, in terms of solubility, dispersibility, and coatability, etc. , Cyclohexanone, 2-heptanone, 2-ethyl hydroxypropionate, 3-methyl-3-methoxybutyl propionate, 3-ethyl methoxypropionate, methyl 3-ethoxypropionate, n-amyl formate, etc. Preferred, and more preferably propylene glycol monomethyl ether acetate.

(Barium sulfate)

In the pigment dispersion composition for a color filter of the present invention, barium sulfate having a primary particle diameter of 5 to 20 nm may be used to improve heat resistance (brightness).

The amount of barium sulfate is used in the range of 0 to 25 parts by mass, preferably 5 to 20 parts by mass per 100 parts by mass of the coloring pigment.

The barium sulfate is used during or after dispersion of the colored pigment subjected to micronization.

The pigment dispersion composition for a color filter of the present invention is mainly composed of a coloring pigment, a pigment dispersant, an alkali-soluble resin, and an organic solvent, and these components total 90 to 100% by mass of the pigment dispersion composition for a color filter. As the pigment dispersant, any ones can be employed from those described above.

It is also possible to use the pigment dispersion composition for color filters of the present invention as a composition for resists without photocurability.

(Additives that can be added as needed)

Various additives, such as a photoinitiator, a thermal polymerization inhibitor, an ultraviolet absorber, and an antioxidant, can be suitably used depending on the method for preparing the pigment dispersion composition for color filters. As said photoinitiator, what is mentioned later is mentioned, for example.

(Method of producing the pigment dispersion composition for color filters of the present invention)

A method of producing a pigment dispersion composition for color filters using the above raw materials will be described. Further, in the case of a pigment-dispersed resist composition for color filters that is not photocurable, it is not necessary to blend a photopolymerizable compound.

For this reason, first, a pigment dispersion composition is prepared as follows.

A mixture comprising a pigment, alkali-soluble resin, a pigment dispersant, an organic solvent, barium sulfate, and other additives as necessary, is obtained by micronization treatment in the presence or absence of a pigment dispersion aid. The obtained mixture is kneaded using various dispersing machines such as a roll mill, a kneader, a high-speed stirring device, a bead mill, a ball mill, a sand mill, an ultrasonic disperser, and a high pressure disperser, and subjected to dispersion treatment to obtain a pigment dispersion composition.

When using a plurality of pigments together, the following method can be adopted.

(1) After obtaining a pigment dispersion composition for each pigment in advance, mixing these pigment dispersion compositions in an arbitrary ratio, and adding a resin, barium sulfate, organic solvent, and other additives as necessary, the color of the present invention To prepare a pigment dispersion composition for a filter.

(2) Prior to the process of mixing the pigment dispersion composition prepared as described above so that the complementary pigment is in a predetermined ratio as necessary, resin, barium sulfate, organic solvent, and other additives are added as necessary. Thus, a pigment dispersion composition is prepared, and a pigment dispersion composition is prepared in the same manner for a pigment dispersion composition having another pigment, and then the pigment dispersion composition for a color filter of the present invention is prepared through a step of mixing them.

In addition, a resin, barium sulfate, organic solvent, and other additives may be added to the pigment dispersion composition for color filters obtained by (1) and (2) as necessary to prepare a pigment dispersion composition for color filters.

Next, it is also possible to obtain a pigment dispersion composition for color filters by mixing the prepared pigment dispersion composition for color filters in a predetermined ratio with respect to the pigment to be contained.

In the production methods (1) and (2) above, in the case of using a micronized pigment that has been micronized in the presence of a pigment dispersion aid having an acidic group, a pigment dispersion aid having an acidic group is used when dispersing the micronized pigment. It is possible to manufacture even if it is not contained.

In addition, in the production methods (1) and (2) above, the resin and barium sulfate can be added at the time of production of the pigment dispersion composition and/or after production of the pigment dispersion composition.

In addition, among the production methods (1) and (2) above, it is preferable to use a pigment subjected to micronization in the presence of a pigment dispersion aid having an acidic group from the viewpoint of obtaining high coloring power and high luminance.

Currently, as a method of manufacturing a color filter using a pigment dispersion resist composition for a color filter, a photoresist method using a photocurable composition is mostly used, but later, a photocurable pigment dispersion composition for a color filter used in the photoresist method, and so on. Divided into pigment dispersion compositions for color filters that are not photocurable, and the components contained in each are described below.

[B. When the pigment dispersion resist composition for color filters is photocurable]

Next, the case where the pigment dispersion resist composition for color filters of the present invention is photocurable will be described.

When the pigment-dispersed resist composition for a color filter of the present invention is photocurable, the composition is a resist composition that has active energy ray curability and can develop alkali, and is mainly composed of a pigment, a pigment dispersant, an alkali-soluble resin and an organic solvent. It contains barium, and further a photopolymerizable compound.

As the kind and compounding amount of the pigment, the pigment dispersant, the resin other than the photopolymerizable compound, barium sulfate, and the organic solvent, it is used as described above for the pigment dispersion composition for color filters.

In addition, the organic solvent is preferably 50% by mass or more, and 70% by mass or more in the pigment dispersion resist composition for color filters of the present invention from the viewpoints of solubility of the alkali-soluble resin, dispersibility of colored pigments, and coating properties. It is more preferable to contain.

(Photopolymerizable compound)

As the photopolymerizable compound used in the pigment dispersion resist composition for a color filter of the present invention, a monomer, oligomer, photopolymerizable resin, etc. having at least one photopolymerizable unsaturated bond in a molecule, and those described in the pigment dispersion composition for a color filter Use the same A monomer, oligomer, etc. having a photopolymerizable unsaturated bond means that the photopolymerization initiator described later has an unsaturated bond that can be polymerized and resinized by the action of radicals or cations generated when the photopolymerization initiator is decomposed by active energy rays such as ultraviolet rays or electron beams. .

As a photopolymerizable compound, as a monomer having one photopolymerizable unsaturated bond in a molecule, methyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, methyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, etc. Alkyl methacrylate or alkyl acrylate; Aralkyl methacrylate or aralkyl acrylate such as benzyl methacrylate and benzyl acrylate; Alkoxyalkyl methacrylate such as butoxyethyl methacrylate and butoxyethyl acrylate Or alkoxyalkyl acrylate; aminoalkyl methacrylate or aminoalkyl acrylate such as N,N-dimethylaminoethyl methacrylate and N,N-dimethylaminoethyl acrylate; diethylene glycol ethyl ether, triethylene glycol butyl ether , Methacrylic acid ester or acrylic acid ester of polyalkylene glycol alkyl ether such as dipropylene glycol methyl ether; methacrylic acid ester or acrylic acid ester of polyalkylene glycol aryl ether such as hexaethylene glycol phenyl ether; isobornyl methacrylic Rate or isobornyl acrylate; glycerol methacrylate or glycerol acrylate; 2-hydroxyethyl methacrylate or 2-hydroxyethyl acrylate.

As a monomer having two or more photopolymerizable unsaturated bonds in a molecule as a photopolymerizable compound, bisphenol A dimethacrylate, 1,4-butanediol dimethacrylate, 1,3-butylene glycol dimethacrylate, and diethylene glycol Dimethacrylate, glycerol dimethacrylate, neopentyl glycol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, Pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol tetramethacrylate, dipentaerythritol hexamethacrylate, dipentaerythritol pentamethacrylate, bisphenol A diacrylate 1,4-butanediol diacrylic Rate, 1,3-butylene glycol diacrylate, diethylene glycol diacrylate, glycerol diacrylate, neopentyl glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, tetraethylene glycol diacrylate Rate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, and the like.

These monomers can be used alone or in combination of two or more.

Further, oligomers obtained by polymerizing a photopolymerizable compound can be used.

As a photopolymerizable resin as a photopolymerizable compound, a photocrosslinkable group such as a (meth)acrylic compound or cinnamic acid is introduced into a linear polymer having reactive substituents such as hydroxyl group, carboxyl group, amino group, etc. Resin is used. Linear polymers containing acid anhydrides such as styrene-maleic anhydride copolymer or α-olefin-maleic anhydride copolymer are half-esterified with a (meth)acrylic compound having a hydroxyl group such as hydroxyalkyl (meth)acrylate One polymer is also used.

The photopolymerizable compounds capable of forming these resins can be used alone or in combination of two or more. In the present invention, the amount of the photopolymerizable compound used is preferably in the range of 3 to 50 mass% in terms of mass fraction with respect to the total solids in the pigment dispersion resist composition for color filters.

(Photopolymerization initiator)

The photopolymerization initiator used in the pigment dispersion resist composition for a color filter of the present invention is not particularly limited as long as it can generate radicals or cations by irradiation with active energy rays such as ultraviolet rays or electron beams. For example, benzophenone, N ,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, benzyl, 2,2-diethoxyacetophenone, benzoin, benzoin methyl ether, benzo Phosphorus isobutyl ether, benzyl dimethyl ketal, α-hydroxyisobutylphenone, thioxanthone, 2-chlorothioxanthone, 1-hydroxycyclohexylphenyl ketone, t-butylanthraquinone, 1-chloroanthraquinone, 2 ,3-dichloroanthraquinone, 3-chloro-2-methylanthraquinone, 2-ethylanthraquinone, 1,4-naphthoquinone, 1,2-benzoanthraquinone, 1,4-dimethylanthraquinone, 2-phenyl Anthraquinone, 2-methyl-1[4-(methylthio)phenyl]-2-morpholinopropane-1-one, triazine-based photopolymerization initiator, and the like. These photopolymerization initiators are used alone or in combination of two or more.

In the present invention, the content of the photopolymerization initiator is preferably in the range of 1 to 20% by mass based on the total solid content in the pigment dispersion resist composition for color filters.

The pigment dispersion resist composition for a color filter of the present invention is mainly composed of a coloring pigment, a pigment dispersion aid, a pigment dispersant, an alkali-soluble resin, a photopolymerizable compound, a photopolymerization initiator, barium sulfate, and an organic solvent. It occupies 90 to 100 mass% in the pigment dispersion resist composition.

(Additives that can be added as needed)

When the pigment-dispersed resist composition for a color filter of the present invention is photocurable, various additives such as a thermal polymerization inhibitor, an ultraviolet absorber, and an antioxidant may be suitably used as needed.

[C. When the pigment dispersion resist composition for color filter is not photocurable]

When the pigment-dispersed resist composition for color filters is not photocurable, it does not contain the photopolymerizable compound or photopolymerization initiator used when the pigment-dispersion resist composition for color filters is photocurable, and additionally the color filter as necessary. Resins other than the photopolymerizable compound shown in the description of the composition of the pigment dispersion composition for use can be blended.

(Additives that can be added as needed)

When the pigment-dispersed resist composition for a color filter of the present invention is not photocurable, various additives such as an ultraviolet absorber and an antioxidant may be suitably used as needed.

(Method for producing a pigment-dispersed resist composition for a color filter of the present invention)

A method of producing a pigment dispersion resist composition for color filters using the above materials will be described. When the pigment dispersion resist composition for color filters is photopolymerizable, a photopolymerizable compound, a photopolymerization initiator, an alkali-soluble resin, barium sulfate, organic solvent, and other additives are added to the pigment dispersion composition for a color filter obtained above. By adding, the pigment dispersion resist composition for color filters of this invention is obtained.

In addition, when it is not photopolymerizable, any one of an alkali-soluble resin, barium sulfate, an organic solvent, and other additives may be further added to obtain the pigment-dispersed resist composition for a color filter of the present invention. The same is true for the above manufacturing method.

In addition, as a method of manufacturing a color filter using the pigment dispersion composition for color filters of the present invention, it can be manufactured by employing a known means as a configuration other than the above pigment dispersion composition, including a device necessary for it.

Example

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples. In addition, unless otherwise specified, "%" shall mean "mass%", and "part" shall mean "mass part".

<Acrylic dispersant>

An acrylic dispersant shown in Table 1 below was obtained.

In Table 1 and Table 2 below,

In the composition column, the part enclosed by (　) represents the block, and the numerical value separated by "/" represents the mass ratio of each monomer. "//" represents the mass ratio of each block. Each dispersant is in the form of a solution obtained by dissolving a solid content concentration of 40% by mass in a mixed solvent having a composition and mixing ratio of PGMEA:PGME = 2:1.

In the composition column, "-b-" indicates that blocks composed of monomers bound by both (　) are block copolymerized. When not bound by (　), it is a random polymer. For example, the acrylic dispersant 1 in Table 1 is a block in which MMA and BMA are randomly polymerized, and a block in which DM is polymerized is block-polymerized. In addition, the numerical value in the composition indicates that MMA is 34 parts by mass, BMA is 33 parts by mass, and DM is 33 parts by mass, as described in the production section of the solution of acrylic dispersant 1 below in the entire block copolymer.

(Monomer)

MMA: methyl methacrylate

BMA: Butyl methacrylate

DM: Dimethylaminoethyl methacrylate

DM-DMBQ: Benzyl chloride quaternary product of DM

2VP: 2-vinylpyridine

PMPMA: Pentamethylpiperidinyl methacrylate

MAA: Methacrylic acid

<Organic solvent>

PGMEA: Propylene glycol monomethyl ether acetate

PGME: Propylene glycol monomethyl ether

(Preparation of a solution of acrylic dispersant 1)

34 g of MMA, 33 g of BMA, and 1 L of THF were added to the degassed glass apparatus, and 4.5 mmol of a hexane solution of n-butyllithium was added (here, a random copolymer portion of MMA and BMA was synthesized).

Then, it cooled to -78 degreeC and stirred for 2 hours. Then, 33 g of DM was added, and the block portion of DM bonded to the random copolymer portion of MMA and BMA was synthesized, and the reaction was stopped after stirring for 2 hours.

The synthesized solution was added dropwise to a large amount of methanol to precipitate. The dispersant is collected with a filter paper, washed several times with methanol, and dried under reduced pressure at 60°C.

The obtained dispersant was added to PGMEA: PGME = 2:1 to obtain a solution of 40 mass% acrylic dispersant 1.

(Preparation of solution of acrylic dispersant 2)

A solution of the acrylic dispersant 2 was obtained in the same manner except that the DM used for the production of the acrylic dispersant 1 was changed to 2VP.

(Preparation of solution of acrylic dispersant 3)

10 g of benzyl chloride was added to the solution of the acrylic dispersant 1 while stirring, and refluxed at 140° C. for 6 hours to obtain a solution of the acrylic dispersant 3.

(Preparation of solution of acrylic dispersant 4)

A solution of the acrylic dispersant 4 was obtained in the same manner except for changing the DM used for the production of the acrylic dispersant 1 to PMPMA.

<Alkali-soluble resin>

An alkali-soluble resin shown in Table 2 below was obtained.

Alkali-soluble resin 1 is a block polymer, and is a 39.7 mass% solution in PGMEA solution.

Alkali-soluble resin 2 is a random polymer and is a 40.6 mass% solution in a PGMEA solution.

(Preparation of alkali-soluble resin solution 1)

30 g of MMA, 50 g of BMA, and 1 L of THF were added to the degassed glass apparatus, and 4.5 mmol of a hexane solution of n-butyllithium was added (here, a random copolymer portion of MMA and BMA was synthesized).

Subsequently, it cooled to -78 degreeC and stirred for 2 hours. Subsequently, 20 g of MAA was added, the block portion of MAA bound to the random copolymer portion of MMA and BMA was synthesized, and the reaction was stopped after stirring for 2 hours.

The synthesized solution was added dropwise to a large amount of methanol to precipitate. The resin is collected with a filter paper, washed several times with methanol, and dried under reduced pressure at 60°C.

The obtained resin was put into PGMEA to obtain a 39.7 mass% alkali-soluble resin solution 1.

(Preparation of alkali-soluble resin solution 2)

3 g of MMA, 5 g of BMA, and 2 g of MAA were added to the flask, and 1,700 mg of AIBN was added to the flask, followed by freezing and deaeration after stirring.

Then, 10 g of benzene was added, followed by stirring while filling dry nitrogen.

It is immersed in a bath at 60° C., reacted for 24 hours, and then immersed in a dry ice methanol bath to stop the reaction.

It is diluted with the same amount of benzene and poured into 300 ml of methanol to precipitate the resulting resin.

The resin is collected with a filter paper, washed several times with methanol, and dried under reduced pressure at 60°C.

The obtained resin (MMA, random copolymer of BMA and MAA) was added to a solvent of PGMEA to obtain a 40.6 mass% alkali-soluble resin solution 2.

<Preparation of pigment dispersion composition>

P. R. 254: Pigment Red 254

Urethane dispersant: Disperbyk 182 (43% solution)

Ester dispersant: Azisper PB821 (no solvent)

Both alkali-soluble resins 1 and 2 are prepared so that the solid content concentration is 35% by mass.

Using the acrylic dispersant shown in Table 1 and the alkali-soluble resin shown in Table 2, adding a red pigment and a solvent, and using a urethane-based dispersant or an ester-based dispersant as Comparative Examples 2 and 3, so that the composition shown in Table 3 below. After mixing, it was kneaded for 10 hours with a paint conditioner using 0.3 mmΦ zirconia beads to obtain a red pigment dispersion composition.

<Initial viscosity>

The viscosity at 25°C was measured using an E-type viscometer (manufactured by Toki Sangyo Corporation, R100-type viscometer model RE100L).

○: Initial viscosity is less than 7.0 mPa·s

△: Initial viscosity is 7.0 to 10.0 mPa·s

×: Initial viscosity exceeds 10.0 mPa·s

<Viscosity stability>

For the pigment dispersion compositions for color filters used in the resist methods of the above Examples and Comparative Examples, each of them was taken in a glass bottle, covered with a cap, and stored at 40°C for 1 week, and then the viscosity at 25°C was measured with the E-type viscometer. Then, it evaluated by the rate of change from the initial value.

○: Viscosity change rate before and after storage is 10% or less

×: The rate of change in viscosity before and after storage exceeds 10%

<Increase rate>

The thickening rate was calculated|required by the formula of (viscosity/initial viscosity after 40 degreeC 1 week) x 100.

<foreign matter>

Each dispersion was taken in a glass bottle, capped, and stored at 5°C for 1 month, and then the glass bottle was allowed to stand at room temperature, and the presence or absence of foreign matter was visually confirmed.

○: No foreign matter

×: There is foreign matter

The red pigment dispersion compositions of Examples A1 to A4 had low initial viscosity and viscosity after storage at 40°C for 1 week. For this reason, the thickening rate (the rate of increase in viscosity) was low.

In contrast, in Comparative Example A5, since the alkali-soluble resin is a random polymer, in Comparative Example A6, since the dispersant is urethane-based and not a block polymer, in Comparative Example A7, since the dispersant is an ester-based and not a block polymer, the initial viscosity and 40°C, respectively. The viscosity after storage for 1 week was all high and the thickening rate was also high.

As shown in Table 5 below, with respect to the generation of foreign matter, according to Examples A1 to A4 and Comparative Examples A5 and A6, it was ○, and in Comparative Example A7, it was ×.

Therefore, according to the present invention, a pigment dispersion having a lower viscosity and excellent storage stability could be obtained.

<Preparation of pigment dispersion resist composition>

Each of the red pigment dispersion compositions of Examples and Comparative Examples described in Table 3, an alkali-soluble resin, a photopolymerizable compound DPHA (dipentaerythritol hexaacrylate), a photoinitiator (irgacure 907), and PGMEA, were prepared in Table 4 After uniformly mixing using a high-speed stirrer so that it might become, it filtered through a membrane filter of 3 micrometers in pore diameter, and the pigment dispersion resist composition for color filters was obtained.

<Production of sample>

The red pigment dispersion resist compositions for color filters of Examples and Comparative Examples were coated on a glass substrate using a spin coater, pre-baked at 100°C for 3 minutes, and then exposed with a high-pressure mercury lamp. Further, it was post-baked for 60 minutes in an oven at 230°C to obtain an evaluation substrate.

<Heat resistance>

For the samples of Examples and Comparative Examples, color characteristics (x, y, Y) were colorimetrically measured with a spectrophotometer (manufactured by Shimadzu Corporation, UV-2500PC, C light source 2° field of view), and chromaticity x = y at 0.600, Luminance Y was calculated. Further, using the produced substrate, contrast measurement was performed using the Tsubosaka Electric Corporation contrast tester CT-1 and the Topcon Corporation luminance meter BM-5A.

<Development residue>

The pigment dispersion resist composition was applied to a glass substrate using a spin coater, and prebaked at 100° C. for 3 minutes. In order to obtain an exposed portion and an unexposed portion, UV exposure (irradiation dose 270 mJ/cm 2) was performed using a photomask. Subsequently, an image was formed by dipping in an alkaline developer (KOH 0.05 wt%), and evaluated according to the following evaluation criteria.

○: There is no residue of non-image part

△: There is a white residue in the non-image area

×: There is residue at the end of the image or there is a colored residue at the non-image

<Alkaline developability>

The pigment dispersion resist composition was applied to a glass substrate using a spin coater. Subsequently, after pre-baking at 100°C for 3 minutes, the dissolved state was visually evaluated by immersing in an alkaline aqueous solution containing 0.05 wt% of KOH and 2.5 wt% of TMAH.

○　: Melting

○△: Dissolve after peeling

△　: weak peeling

×　: Peel

＜PGMEA re-solubility＞

The pigment-dispersed resist composition was applied to a glass substrate using a spin coater, pre-baked at 100°C for 3 minutes, and then the prepared substrate was immersed in PGMEA to visually evaluate the dissolution state.

○: Melting

×：Removal

According to Examples B1 to B4, which are examples according to the present invention, a sufficiently high contrast was obtained, and no residue was left after development, so that it was sufficiently dissolved in an aqueous potassium hydroxide solution and an aqueous TMAH solution, and also excellent resolubility in PGMEA.

On the other hand, according to Comparative Example B5 in which the alkali-soluble resin was not a block polymer, it was only peeled off without being dissolved in the aqueous potassium hydroxide solution and the aqueous TMAH solution.

Further, according to Comparative Example B6 in which the alkali-soluble resin contained a resin other than a block polymer, it was only slightly peeled or peeled without being dissolved in the aqueous potassium hydroxide solution and the aqueous TMAH solution.

In addition, as in Comparative Example B7, when the dispersant was urethane-based and not a block polymer, heat resistance was inferior, and at the same time, it was not dissolved in the aqueous potassium hydroxide solution and the aqueous TMAH solution, but only slightly peeled or peeled off.

As in Comparative Example B8, an ester-based dispersant was used as the dispersant. When it was not a block copolymer, it was a result of having a colored residue in a non-image part at the time of development.

According to the results of each example, the pigment dispersions of Examples A1 to A4 have low viscosity and excellent viscosity stability, while the pigment dispersion resist compositions of Examples B1 to B4 were able to dissolve the resist by using an aqueous potassium hydroxide solution and an aqueous TMAH solution. . However, according to the results of Comparative Examples B5 to B8, there were cases in which re-dissolution was not sufficiently possible, heat resistance was inferior, or there was a residue after development. As a result, with the pigment dispersion composition for color filters of the present invention, all of the viscosity stability, PGMEA resolubility, alkali developer solubility and heat resistance of the pigment dispersion resist composition for color filters were improved, and development was possible without residue.

Claims (10)

A pigment dispersion composition for color filters containing a coloring pigment, a pigment dispersant, an alkali-soluble resin and an organic solvent, wherein the pigment dispersant contains an acrylic block polymer containing an amino group and/or a pyridine ring, and the alkali-soluble resin is a block polymer Pigment dispersion composition for color filters containing. The method of claim 1,
Pigment dispersion composition for color filters containing a photopolymerizable compound. The method according to claim 1 or 2,
A pigment dispersion composition for color filters containing 1 to 200% by mass of an alkali-soluble resin of a block polymer with respect to the coloring pigment. The method according to any one of claims 1 to 3,
A pigment dispersion composition for color filters, wherein a pigment dispersant of an acrylic block polymer and/or an alkali-soluble resin of a block polymer is synthesized by living polymerization. The method according to any one of claims 1 to 4,
The pigment dispersion composition for color filters, wherein the amine contained in the pigment dispersant of the acrylic block polymer is a tertiary amine or a quaternary amine. The method according to any one of claims 1 to 5,
A pigment dispersion composition for color filters in which an alkali-soluble resin of the block polymer is localized in the molecule of the block polymer. The method according to any one of claims 1 to 6,
A pigment dispersion composition for color filters in which an amine moiety is localized in the molecule of the block polymer in the pigment dispersant of the acrylic block polymer. The method according to any one of claims 1 to 7,
The pigment dispersion composition for color filters in which the acid value of the alkali-soluble resin of the block polymer is 5 to 250 mgKOH/g. The method according to any one of claims 1 to 8,
A pigment dispersion composition for color filters in which the amine value of the pigment dispersant of the acrylic block polymer is 40 to 200 mgKOH/g. The pigment dispersion resist composition for color filters containing the pigment dispersion composition for color filters in any one of Claims 1-9.