JP2007314681A - Manufacturing method of pigment composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To give a pigment composition that can give a red filter having good brightness. <P>SOLUTION: The manufacturing method of a pigment composition comprises the step of wet grinding dianthraquinonyl pigments or dianthraquinonyl pigments in the presence of the compound expressed by formula 1, wherein Q is NH(CH<SB>2</SB>)nNR<SP>1</SP>R<SP>2</SP>or a hydroxy group, R is NH(CH<SB>2</SB>)nNR<SP>1</SP>R<SP>2</SP>, R<SP>1</SP>and R<SP>2</SP>are each 1-4C alkyl group or a 5 or 6 member ring structure that may contain a new nitrogen atom or oxygen atom generated by combining R<SP>1</SP>and R<SP>2</SP>, and n is an integer of 1-4. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing a pigment composition, and more specifically, a composition of a diketopyrrolopyrrole pigment or a dianthraquinone pigment useful as a pigment for a color filter used in a color liquid crystal display device, a solid-state imaging device or the like. About.

  Conventionally, red pigments for color filters used in color liquid crystal display devices, solid-state imaging devices, etc. use dianthraquinone pigments, diketopyrrolopyrrole pigments, etc., which have high lightness and excellent light resistance and heat resistance. It was. However, there is a strong demand for pigments with higher brightness, and for this purpose, it was necessary to further refine the primary particle diameter of the pigments to improve transparency.

As a method for reducing the primary particle diameter of a pigment, Patent Document 1 discloses a method in which a pigment is wet-pulverized in the presence of a synthetic resin that is solid and water-insoluble at room temperature. Patent Document 2 discloses a method of wet pulverizing a dianthraquinone pigment in the presence of an anthraquinone derivative. Patent Document 3 discloses a method of wet pulverizing a diketopyrrolopyrrole pigment in the presence of a pigment derivative.
However, dianthraquinone pigments or diketopyrrolopyrrole pigments obtained by these methods are insufficient in performance such as brightness.
Japanese Patent Laid-Open No. 7-13016 Japanese Patent Laid-Open No. 10-245501 JP 2001-220520 A

  An object of this invention is to provide the pigment composition which gives the red filter with favorable brightness.

That is, the present invention relates to a method for producing a pigment composition, which comprises wet pulverizing a dianthraquinone pigment or diketopyrrolopyrrole pigment in the presence of a compound represented by the following formula 1.
Formula 1

（但し、式中、ＱはＮＨ（ＣＨ_２）ｎＮＲ^１Ｒ^２又は水酸基を表し、ＲはＮＨ（ＣＨ_２）ｎＮＲ^１Ｒ^２を表し、Ｒ^１、Ｒ^２は炭素数１〜４のアルキル基又はＲ^１とＲ^２が一体となって新たな窒素原子又は酸素原子を含んでもよい５員環構造又は６員環構造を表し、ｎは１〜４の整数を表す。）

(In the formula, Q represents NH (CH ₂ ) nNR ¹ R ² or a hydroxyl group, R represents NH (CH ₂ ) nNR ¹ R ² , and R ¹ and R ² are alkyl groups having 1 to 4 carbon atoms. Alternatively, R ¹ and R ² are combined to represent a 5-membered or 6-membered ring structure that may contain a new nitrogen atom or oxygen atom, and n represents an integer of 1 to 4.)

  Furthermore, this invention relates to the manufacturing method of Claim 1 whose pigment composition is a color filter use.

  Furthermore, this invention relates to the pigment composition obtained by the said manufacturing method.

  The present invention further relates to a pigment dispersion comprising the above pigment composition and a pigment carrier.

  By blending the compound represented by Formula 1 during wet pulverization, the crystal growth of the dianthraquinone pigment or diketopyrrolopyrrole pigment is suppressed and the above-mentioned fineness can be obtained. In addition, by using the dianthraquinone pigment or diketopyrrolopyrrole pigment of the present invention, a color filter having a red pixel having high brightness characteristics can be obtained.

  The compound represented by Formula 1 in the present invention functions to suppress crystal growth of a dianthraquinone pigment or diketopyrrolopyrrole pigment during wet grinding. The compound represented by Formula 1 is preferably used in an amount of 0.5 to 20% by weight, particularly 2 to 15% by weight, based on the dianthraquinone pigment or diketopyrrolopyrrole pigment. If the amount of the compound represented by Formula 1 is more than the above value, the resistance of the pigment is impaired, which is not preferable. The timing of adding the compound represented by Formula 1 to the pigment may be before wet pulverization or during wet pulverization.

The dianthraquinone pigment in the present invention is a compound represented by the following formula 2.
Formula 2

(However, in the formula, each A independently represents a hydrogen atom or an alkyl group which may have a substituent or an aryl group which may have a substituent.)

The alkyl group as the substituent A in Formula 2 is preferably an alkyl group having 1 to 4 carbon atoms, and examples of the substituent of the alkyl group include a halogen atom such as chlorine and a phenyl group.
The aryl group as the substituent A in Formula 2 is preferably a phenyl group, and examples of the substituent of the aryl group include a halogen atom such as chlorine, an alkyl group having 1 to 4 carbon atoms, and a phenyl group.

  Commercially available dianthraquinone pigments include C.I. I. Pigment Red 89, 177, etc., but as a color filter application, C.I. I. Pigment Red 177 is preferable.

The diketopyrrolopyrrole pigment in the present invention and a compound represented by the following formula 3.
Formula 3

(In the formula, each B independently represents a hydrogen atom, an optionally substituted alkyl group, an optionally substituted aryl group, a cyano group or a halogen atom.)

The alkyl group as the substituent B in Formula 3 is preferably an alkyl group having 1 to 4 carbon atoms, and examples of the substituent of the alkyl group include a halogen atom such as chlorine and a phenyl group.
The aryl group as the substituent B in the formula 3 is preferably a phenyl group, and the substituent of the aryl group is a halogen atom such as chlorine, an alkyl having 1 to 4 carbon atoms such as a methyl group, an ethyl group or a t-butyl group. Groups, phenyl groups and the like.
The halogen atom as substituent B in formula 3 is preferably chlorine.

  Commercially available diketopyrrolopyrrole pigments include C.I. I. Pigment red 254, 255, 264, C.I. I. Pigment Orange 71 and the like, but as a color filter, C.I. I. Pigment Red 254 is preferred.

  Even if the dianthraquinone pigment or diketopyrrolopyrrole pigment used in the present invention for wet grinding is a crude pigment containing coarse particles having a particle size of 1 μm or more, the average particle size is 0.02 to 0.00. It may have a particle size of about 2 μm generally used as a pigment. The dianthraquinone pigment and the diketopyrrolopyrrole pigment may be mixed and used for wet grinding.

  In the present invention, wet pulverization means a mixture containing a water-soluble inorganic salt and a water-soluble organic solvent that does not substantially dissolve the water-soluble inorganic salt together with a dianthraquinone pigment or diketopyrrolopyrrole pigment and the compound represented by Formula 1. After mechanically kneading with a kneader or the like, the mixture is poured into water and stirred with a high speed mixer or the like to form a slurry, and then the slurry is filtered and washed with water to remove the water-soluble inorganic salt and the water-soluble organic solvent. The operation to remove.

  The water-soluble inorganic salt serves as a crushing aid, and the pigment is crushed using the high hardness of the inorganic salt during salt milling, and the primary particles of the pigment are refined. The water-soluble inorganic salt is not particularly limited as long as it is soluble in water, and sodium chloride, barium chloride, potassium chloride, sodium sulfate, etc. can be used, but sodium chloride (salt) is used from the viewpoint of price. Is preferred. The amount of the inorganic salt used in the wet pulverization is preferably 1 to 20 times by weight, particularly 3 to 10 times by weight of the pigment, from the viewpoint of both processing efficiency and production efficiency. This is because as the amount ratio of the inorganic salt to the pigment is larger, the finer efficiency is higher, but the amount of processing of one pigment is reduced.

  The water-soluble organic solvent functions to wet the pigment, the compound represented by Formula 1 and the water-soluble inorganic salt, dissolves (mixes) in water, and does not substantially dissolve the water-soluble inorganic salt used. If it is a thing, it will not specifically limit. However, a high boiling point solvent having a boiling point of 120 ° C. or higher is preferable from the viewpoint of safety because the temperature rises during wet pulverization and the solvent easily evaporates. Examples of the water-soluble organic solvent include 2-methoxyethanol, 2-butoxyethanol, 2- (isopentyloxy) ethanol, 2- (hexyloxy) ethanol, diethylene glycol, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol. , Triethylene glycol monomethyl ether, liquid polyethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, liquid polypropylene glycol, etc. Is used.

  At the time of wet pulverization, a resin can be used in combination in order to prevent strong aggregation at the time of drying the finely divided pigment so that it can be easily dispersed in the transparent resin. A soft powder pigment can be obtained by using a resin together during wet pulverization. The resin that can be used in combination with wet pulverization is preferably a solid that is solid at room temperature, water-insoluble, and at least partially soluble in the organic solvent, and is modified with a natural resin, a modified natural resin, a synthetic resin, or a natural resin. A synthetic resin or the like is used. As the natural resin, rosin is typical, and as the modified natural resin, rosin derivatives, fiber derivatives, rubber derivatives, protein derivatives and oligomers thereof are used. Examples of the synthetic resin include epoxy resin, acrylic resin, maleic acid resin, butyral resin, polyester resin, melamine resin, phenol resin, polyurethane resin, and polyamide resin. Examples of synthetic resins modified with natural resins include rosin-modified maleic acid resins and rosin-modified phenolic resins. The amount of the resin used is preferably in the range of 5 to 100% by weight with respect to the pigment.

  At the time of wet pulverization, in addition to the above resins, additives such as pigment dispersion aids and plasticizers, or inorganic pigments such as calcium carbonate, barium sulfate and silica generally used as extender pigments may be used in combination. Moreover, in order to adjust a hue, you may mix and process with another pigment.

  The pigment composition of the present invention becomes a pigment dispersion by being dispersed in a pigment carrier comprising various vehicles. Various dispersing means such as a three-roll mill, a two-roll mill, a sand mill, and a kneader can be used for dispersing the pigment on the pigment carrier. Moreover, in order to make these dispersion | distribution favorable, dispersion | distribution adjuvants, such as various surfactant and a pigment derivative, can be added suitably.

In the present invention, examples of the pigment carrier constituting the pigment dispersion include a vehicle for ink, a paint, or a colored plastic.
Examples of vehicles for offset ink include rosin-modified phenolic resin, petroleum resin, alkyd resin, or 20 to 50% by weight of these drying oil-modified resins, and 0 to 30% by weight of drying oil such as linseed oil, tung oil, soybean oil, etc. %, N-paraffin, isoparaffin, aromatech, naphthene, α-olefin, and the like.

  Examples of gravure ink vehicles include gum rosin, wood rosin, tall oil rosin, lime rosin, rosin ester, maleic acid resin, polyamide resin, vinyl resin, nitrocellulose, cellulose acetate, ethyl cellulose, chlorinated rubber, cyclized rubber, ethylene-acetic acid Vinyl copolymer resin, polyurethane resin, polyester resin, alkyd resin, acrylic resin, gilsonite, dammar, shellac, etc., or a mixture thereof, or a water-soluble resin obtained by water-solubilizing the above resin or a mixture thereof, or an emulsion resin of 10 to 50 weights And 30 to 80% by weight of a solvent such as hydrocarbon, alcohol, ketone, ether alcohol, ether, ester or water.

  Examples of paint vehicles include acrylic resins, alkyd resins, epoxy resins, chlorinated rubber, vinyl chloride, synthetic resin emulsions, silicone resins, fluororesins, polyurethane resins, polyester resins, melamine resins, urea resins, etc., or mixtures thereof. Alternatively, a water-soluble resin obtained by water-solubilizing the above resin or a mixture thereof, or emulsion resin 20 to 80% by weight and a solvent such as hydrocarbon, alcohol, ketone, ether alcohol, ether, ester, water or the like 10 to 60% by weight Is mentioned.

  Examples of plastic vehicles include polyethylene, polypropylene, polybutadiene, ethylene ionomer, polyvinyl chloride, polyvinylidene chloride, ABS resin, acrylic resin, methacrylic resin, polyvinyl alcohol, cellulose plastic, epoxy resin, polyester resin, phenol resin. , Urea resin, melamine resin, polyurethane resin, silicone resin, polyamide resin, polystyrene, polyacetal, polycarbonate, polyphenylene ether, polyphenylene sulfite, polysulfone, polyether imide, polyether ketone, and composites thereof.

  Examples of water-based color vehicles include at least one selected from nonionic, anionic, and cationic surfactants, or sulfonic acid amide, hydroxystearic acid, and ε-caprolactam polymer dispersants; Examples thereof include polyhydric alcohols such as glycerin, ethylene glycol, triethylene glycol, propylene glycol, and pentaerythritol, water, and if necessary, auxiliary agents such as amines, preservatives, and antifoaming agents.

  The color filter ink uses a transparent resin or a precursor thereof as a vehicle. The transparent resin is a resin having a transmittance of 80% or more, preferably 95% or more in the entire wavelength region of 400 to 700 nm in the visible light region. The transparent resin includes a thermosetting resin, a thermoplastic resin, and a photosensitive resin, and the precursor of the transparent resin includes a monomer, an oligomer, and the like that are cured by radiation irradiation to form a coating film similar to the resin. These can be used alone or in admixture of two or more. A photoinitiator or the like is used for curing the pigment dispersion obtained as a resist ink by ultraviolet irradiation. However, since a high-temperature heating process is performed in a later process in the production of the color filter, it is necessary to use a resin having good resistance even in the heating process. In addition, since processing with various solvents and chemicals is also performed in a later process, the solvent resistance and chemical resistance of the formed image are also required. A pigment composition and transparent resin are mix | blended in the ratio of 1: 4-10: 1 in solid content weight ratio.

  Examples of thermosetting resins and thermoplastic resins used in color filter resists include butyral resin, styrene-maleic acid copolymer, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, and vinyl chloride-vinyl acetate copolymer. , Polyvinyl acetate, polyurethane resin, phenol resin, polyester resin, acrylic resin, alkyd resin, styrene resin, polyamide resin, rubber resin, cyclized rubber, epoxy resin, celluloses, polybutadiene, polyimide resin, benzoguanamine resin, A melamine resin, a urea resin, etc. are mentioned.

  The photosensitive resin blended in the color filter resist ink includes a linear polymer having a reactive substituent such as a hydroxyl group, a carboxyl group, and an amino group via an isocyanate group, an aldehyde group, an epoxy group, and the like ( A resin into which a photocrosslinkable group such as a (meth) acrylic compound or cinnamic acid is introduced is used. Further, a linear polymer containing an acid anhydride such as a styrene-maleic anhydride copolymer or an α-olefin-maleic anhydride copolymer is converted into a (meth) acrylic compound having a hydroxyl group such as hydroxyalkyl (meth) acrylate. Half-esterified polymers can also be used.

  Monomers and oligomers that are cured by irradiation with radiation used as color filter resist inks to form a coating film similar to a resin include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, cyclohexyl ( Caprolactone adduct of (meth) acrylate, polyethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tricyclodecanyl (meth) acrylate, dipentaerythritol hexa (meth) acrylate Acrylic esters and methacrylic esters such as hexa (meth) acrylate, acrylic acid, methacrylic acid, (meth) acrylamide, N-hydroxymethyl (meth) acrylic Bromide, styrene, vinyl acetate, acrylonitrile, melamine (meth) acrylate, epoxy (meth) acrylate prepolymer, and the like.

   As photoinitiators to be blended in resist inks for color filters, 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, diethoxyacetophenone, 1- (4-isopropylphenyl) -2-hydroxy-2-methyl Acetophenone photoinitiators such as propan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, benzoin, benzoin methyl ether Benzoin ethyl ether, benzoin isopropyl ether, benzyl dimethyl ketal, benzoin, benzophenone photoinitiator, benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxy Benzophenone photoinitiators such as nzophenone, acrylated benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthio Thioxanthone photoinitiators such as xanthone, 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl) -4 , 6-Bis (trichloromethyl) -s-triazine, 2- (p-tolyl) -4,6-bis (trichloromethyl) -s-triazine, 2-piphenyl-4,6-bis (trichloromethyl)- s-triazine, 2,4-bis (trichloromethyl) -6-styryl s-triazine 2- (naphth-1-yl) -4,6-bis (trichloromethyl) -s-triazine, 2- (4-methoxy-naphth-1-yl) -4,6-bis (trichloromethyl) -s- Triazine photoinitiators such as triazine, 2,4-trichloromethyl- (piperonyl) -6-triazine, 2,4-trichloromethyl (4′-methoxystyryl) -6-triazine, and carbazole photoinitiators, imidazole A compound such as a photoinitiator is used.

  The photoinitiator may be used alone or in combination of two or more. As a sensitizer, α-acyloxime ester, acylphosphine oxide, methylphenylglyoxylate, benzyl, 9,10-phenanthrenequinone, Combined use of compounds such as camphorquinone, ethylanthraquinone, 4,4'-diethylisophthalophenone, 3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, 4,4'-diethylaminobenzophenone You can also

  Examples of the solvent used in the resist ink for color filter include cyclohexanone, ethyl cellosolve acetate, butyl cellosolve acetate, 1-methoxy-2-propyl acetate, diethylene glycol dimethyl ether, ethylbenzene, ethylene glycol diethyl ether, xylene, ethyl cellosolve, and methyl-n. Examples include amyl ketone, propylene glycol monomethyl ether toluene, methyl ethyl ketone, ethyl acetate, methanol, ethanol, isopropyl alcohol, butanol, isobutyl ketone, and petroleum solvents. These are used alone or in combination.

  Hereinafter, the present invention will be described based on examples. In addition, in an example, a part shows a weight part and% shows weight%, respectively. The primary particle diameter of the pigment was measured by observation with a transmission electron microscope, and the specific surface area was measured by the BET method. Prior to Examples, Table 1 shows compounds represented by Formula 1 used in Examples. Further, Table 2 shows dye derivatives described in Examples of JP-A No. 2001-220520 used as a comparison.

(Synthesis of acrylic resin) Put 800 parts of cyclohexanone in a reaction vessel, heat to 100 ° C while injecting nitrogen gas into the vessel, and drop the mixture of the following monomers and thermal polymerization initiator at the same temperature over 1 hour. A polymerization reaction was performed.
Styrene 60.0 parts Methacrylic acid 60.0 parts Methyl methacrylate 65.0 parts Butyl methacrylate 65.0 parts Azobisisobutyronitrile 10.0 parts After dropping and further reacting at 100 ° C for 3 hours, azobis A solution prepared by dissolving 2.0 parts of isobutyronitrile in 50 parts of cyclohexanone was added, and the reaction was further continued at 100 ° C. for 1 hour to synthesize a resin solution. After cooling to room temperature, about 2 g of the resin solution was sampled, heated and dried at 180 ° C. for 20 minutes to measure the nonvolatile content, and cyclohexanone was added to the previously synthesized resin solution so that the nonvolatile content was 20%. An acrylic resin solution was prepared.

  144 parts of DPP pigment (“Irgazine DPP REDBO”, CI Pigment RED254, manufactured by Ciba Specialty Chemicals), 16 parts of compound (a), 1600 parts of sodium chloride, and 190 parts of diethylene glycol are made of 1 gallon kneader made of stainless steel (Inoue Manufacturing Co., Ltd.) And kneaded at 60 ° C. for 10 hours. Next, the mixture is poured into 3 liters of warm water, stirred at a high speed mixer for about 1 hour while being heated to about 80 ° C. to form a slurry, filtered and washed repeatedly to remove sodium chloride and solvent, and then 80 After drying for 1 day at 0 ° C., 156.0 parts of a pigment for a color filter (primary particle size 30 to 40 nm, specific surface area 88 m 2 / g) was obtained.

  The same procedure as in Example 1 except that the DPP pigment was changed to “chromophthaled red A2B” (CI Pigment RED177) manufactured by Ciba Specialty Chemicals and the compound (a) was replaced with the compound (b). And 158.1 parts of a pigment for a color filter (primary particle diameter of 30 to 40 nm, specific surface area of 92 m2 / g) was obtained.

  The same operation as in Example 1 was carried out except that the compound (a) was replaced with the compound (c) to obtain 156.5 parts of a color filter pigment (primary particle size of 30 to 40 nm, specific surface area of 89 m <2> / g). .

  156.0 parts of a pigment for a color filter were prepared in the same manner as in Example 1 except that the amount of DPP pigment was changed from 144 parts to 136 parts and 16 parts of compound (a) was changed to 24 parts of compound (d). (Primary particle diameter of 20 to 30 nm, specific surface area of 95 m2 / g) was obtained.

[Comparative Example 1] Except for the removal of the compound (a), the same operation as in Example 1 was carried out to obtain 149.0 parts of treated pigment (primary particle size 40-50 nm, specific surface area 81 m2 / g).

[Comparative Example 2] Except for the removal of the compound (b), the same operation as in Example 2 was carried out to obtain 149.0 parts of treated pigment (primary particle diameter 60-80 nm, specific surface area 65 m2 / g).

[Comparative Example 3] 151.2 parts of treated pigment (primary particle size 30 to 40 nm, specific surface area 85 m2 / g) was carried out in the same manner as in Example 1 except that the compound (a) was replaced with the compound (e). Got.

[Comparative Example 4] 152.0 parts of treated pigment (primary particle size 30 to 40 nm, specific surface area 87 m2 / g) was carried out in the same manner as in Example 1 except that the compound (a) was replaced with the compound (f). Got.

Mixtures having the following compositions containing the pigments obtained in Examples and Comparative Examples were uniformly stirred and mixed, and then filtered through a 1 μm filter to prepare an alkali developing type photosensitive coloring composition.
Pigment 4.5 parts Acrylic resin solution 24.0 parts Trimethylolpropane triacrylate 5.4 parts ("NK ester ATMPT" manufactured by Shin-Nakamura Chemical Co., Ltd.)
Photoinitiator ("Irgacure 907" manufactured by Ciba Geigy) 0.3 parts
Sensitizer (Hoabaya Chemical "EAB-F") 0.2 parts
65.1 parts cyclohexanone

  Using the obtained photosensitive coloring composition, a color material layer was formed on a transparent substrate by the following method, and the chromaticity of the color material layer was evaluated. The results are shown in Table 3. The obtained photosensitive coloring composition was applied on a 100 mm × 100 mm, 1.1 mm thick glass substrate using a spin coater to obtain a coated substrate. Next, after drying at 70 ° C. for 20 minutes, ultraviolet exposure was performed with an integrated light amount of 150 mJ using an ultrahigh pressure mercury lamp. After exposure, the mixture was heated at 230 ° C. for 1 hour and allowed to cool, and then the chromaticity (Y, x, y) with a C light source was measured using a microspectrophotometer (“OSP-SP100” manufactured by Olympus Optical Co., Ltd.). This operation was repeated by changing the number of rotations of the spin coater, and the brightness was compared with the Y value of the substrate whose film thickness was adjusted so that x of chromaticity was 0.6.

  The photosensitive coloring composition application | coating board | substrate using the pigment of Examples 1-4 showed high Y value compared with that of Comparative Examples 1-4, and was excellent in the brightness.

Claims (4)

A method for producing a pigment composition, comprising wet pulverizing a dianthraquinone pigment or diketopyrrolopyrrole pigment in the presence of a compound represented by the following formula 1.
Formula 1

(In the formula, Q represents NH (CH ₂ ) nNR ¹ R ² or a hydroxyl group, R represents NH (CH ₂ ) nNR ¹ R ² , and R ¹ and R ² are alkyl groups having 1 to 4 carbon atoms. Alternatively, R ¹ and R ² are combined to represent a 5-membered or 6-membered ring structure that may contain a new nitrogen atom or oxygen atom, and n represents an integer of 1 to 4.) The production method according to claim 1, wherein the pigment composition is used for a color filter. A pigment composition obtained by the production method according to claim 1 or 2. A pigment dispersion comprising the pigment composition according to claim 3 and a pigment carrier.