JPH05281414A - Pigment composition for color filter - Google Patents

Abstract

PURPOSE:To enable the prepn. of the pigment compsn. having various spectral characteristics by arbitrarily combining >=2 kinds of pigments. CONSTITUTION:The compsn. consisting of org. high polymers and org. pigments are the solid solns. of >=2 kinds of the pigments. Further, the org. high polymers are the photosensitive resins consisting of a photopolymerizable compd. having at least >=1 ethylenic unsatd. double bonds and a photopolymn. initiator and other resins in some cases. The more specific examples of the pigments to be used include a perylene pigment, quinacridone pigment, anthraquinone pigment, monoazo pigment, disazo pigment, etc. The org. high polymers to be used include an epoxy resin, melamine resin, acrylic resin, polyimide resin and a polyamic acid resin, polyester resin, etc., which are the precursors thereof. The pigment compsn. obtd. in such a manner has excellent dispersion stability and therefore, the chance in transmittance and depolarizating rate by resting are small and the dispersion stability and spectral characteristics are improved.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a pigment composition for a color filter and a color filter using the same. More specifically, the present invention relates to a color filter having excellent optical properties used in a liquid crystal display device and the like and a pigment composition for the same.

[0002]

2. Description of the Related Art Color filters used in color liquid crystal display devices and the like, which are being converted from the CRT system, are
It is composed of fine pixels colored in at least two kinds of hues and a black matrix provided for the purpose of blocking light between the pixels. As a method for producing this color filter, a dyeing method using a dye, a dye internal addition method, a pigment internal addition method using a pigment, an electrodeposition method, an electric field micelle method,
Printing method and the like. Among these methods, the method using a pigment is characterized in that it is excellent in heat resistance and light resistance, and that the process for producing a color filter is simpler than in the dyeing method.

However, in the method using a pigment, the visible light is transmitted through the pixel, and the pigment particles have a half of the transmission wavelength.
The particle size must be up to the particle size of.
Therefore, the pigment for a color filter must have the properties of being sufficiently practical in terms of heat resistance and light resistance and being easy to be made into fine particles. Generally, when two or more kinds of pigments are used in combination when the pigment is dispersed into fine particles, heteroaggregation is likely to occur, a dispersion having good transmittance is difficult to obtain, and stable rheology is also difficult to obtain. Therefore, there are few pigments that satisfy the various conditions required for color filter pigments, and it is often difficult to mix and use two or more kinds of pigments. Therefore, the selection is more difficult than the method using dyes. At present, the choice of pigments that can be used is limited in terms of spectral characteristics.

Further, in the case of liquid crystal display, as disclosed in the literature reported by IBM Japan, Ltd. at the 1990 Color Engineering Conference, in the method using a pigment, the pigment is in the pixel of the color filter. Since the polarized light obtained through the polarizing plate is partly scattered by the pigment particles and the polarization property is impaired (this is called depolarization effect), the display quality of liquid crystal, especially its contrast uses a dye. It is lower than the method, and when using a yellow pigment, there is a problem that its properties are remarkable.

[0005]

In the production of a color filter using an organic pigment, a pigment composition for a color filter, which can obtain various spectral characteristics and enables a high display quality in a liquid crystal display, is desired.

[0006]

DISCLOSURE OF THE INVENTION The inventors of the present invention have made diligent efforts to find a method for producing a color filter which has various spectral characteristics as described above and has a good liquid crystal display quality. As a result, a specific pigment composition is obtained. However, the present invention has been completed by finding that the above characteristics are satisfied.

That is, the present invention provides (1) a composition comprising an organic polymer and an organic pigment,
The organic pigment is a solid solution of two or more kinds of pigments, and a pigment composition for a color filter (2) The organic polymer has a photopolymerizable compound having at least one ethylenically unsaturated double bond and light. Pigment composition for color filter according to (1), which is a photosensitive resin comprising a polymerization initiator and other resin as the case may be. (3) The other resin may be a film-forming polymer binder and / or Or a pigment composition for a color filter according to (2), which is a thermopolymerizable resin. (4) The solid solution of the pigment is CI pigment Red.
177 and a yellow pigment (1) to (3), which is a pigment composition for a color filter (5) The yellow pigment is a dichlorobenzidine-based disazo pigment (4) Pigment composition for color filter described (6) Pigment composition for color filter described in (4), characterized in that the yellow pigment is an isoindolinone pigment (7) The solid solution of the pigment is CI pigment Blu.
(15) The pigment composition for a color filter according to any one of (1) to (3), characterized in that it is a violet pigment. (8) The violet pigment is a carbazole dioxazine pigment (7) Pigment composition for color filter described in (8) Pigment for color filter described in (1) to (3), wherein the solid solution of the pigment is a compound represented by the following formula (1) and a yellow pigment. Composition

[0008]

[Chemical 3]

(R ₁ , R ₂ , R ₃ and R ₄ each independently represent hydrogen, chlorine or bromine.) (10) The yellow pigment is a dichlorobenzidine-based disazo pigment ( (9) The pigment composition for a color filter according to (9), wherein the yellow pigment is an isoindolinone pigment, the pigment composition for a color filter according to (9), (12) a solid solution of the pigment is The pigment composition for color filters according to (1) to (3), which is a compound represented by formula (2) and a yellow pigment.

[0010]

[Chemical 4]

(R ₁ and R ₂ are each independently hydrogen,
Chlorine, bromine, an alkoxy group, an alkyl group, a nitro group, a carboanilide group or an alkoxycarbonyl group, R
Represents hydrogen, chlorine, bromine, an alkoxy group, an alkyl group, a nitro group, a carboanilide group, a phenyl group or a benzimidazolone group mono- or di-substituted with an alkoxycarbonyl group. (13) The pigment composition for a color filter according to (12), wherein the yellow pigment is a dichlorobenzidine-based disazo pigment. (14) The yellow pigment is an isoindolinone-based pigment. (12) Pigment composition for color filter (15) A color filter produced using the pigment composition for a color filter of (1) to (14).

The pigment composition for a color filter of the present invention and the color filter produced using the same will be described in detail. In the present invention, two or more kinds of pigments selected from various organic pigments are made into a solid solution by a known method described below. Specific examples of usable pigments include perylene pigments, quinacridone pigments, and anthraquinone pigments. , Monoazo pigments, disazo pigments, pyrrolopyrrole pigments, isoindolinone pigments, phthalocyanine pigments,
Examples thereof include halogenated phthalocyanine-based pigments and dioxazine-based pigments, and specific examples thereof are shown by color index (CI) numbers.

C. I. Yellow pigment 20, 24, 83, 86, 9
3, 109, 110, 117, 125, 137, 13
8, 147, 148, 153, 154, 166, 168 C.I. I. Red pigment 9, 97, 122, 123, 1
49, 168, 177, 180, 192, 208, 21
5, 216, 217, 220, 223, 224, 22
6, 227, 228, 240 C.I. I. Purple pigment 19, 23, 29, 30, 37,
40, 50 C.I. I. Blue pigment 15, 15: 1-6, 22, 6
0, 64 C.I. I. Green pigment 7,36

The organic pigments used are not limited to the above-mentioned pigments, and examples of preferable combinations include the following combinations.・ The solid solution of the pigment is CI pigment Red 1
77 and a yellow pigment, and the yellow pigment is particularly a dichlorobenzidine-based disazo pigment or an isoindolinone-based pigment.・ Pigment solid solution is CI pigment Blue
15 and a violet pigment, and the violet pigment is a carbazole dioxazine pigment. The pigment solid solution comprises a compound represented by the formula (1) and a yellow pigment, and the yellow pigment is particularly a dichlorobenzidine-based disazo pigment or an isoindolinone-based pigment. The solid solution of the pigment is a compound represented by the formula (2) and a yellow pigment, and the yellow pigment is particularly a dichlorobenzidine-based disazo pigment or an isoindolinone-based pigment.

Two or more kinds of pigments selected from these pigments are treated with other additives and the like in a ball mill or the like, or are dissolved in a solvent in which the pigment such as sulfuric acid is dissolved and mixed, and then a solvent which does not dissolve the pigment. It is made into a solid solution by precipitating in it.

The organic polymer used in the present invention includes:
As a matter of course, a color filter must be a polymer that is colorless and transparent and has excellent heat resistance and light resistance. Specific examples thereof include the following.

That is, an epoxy resin, a melamine resin, an acrylic resin, a polyimide resin and its precursors, a polyamic acid resin, a polyester resin, an unsaturated polyester resin, a polycarbonate resin, a photosensitive monomer having a (meth) acryloyl group, and Oligomers, other resins, etc., and particularly preferred organic polymers are photopolymerizable compounds having at least one ethylenically unsaturated double bond, and examples thereof include the following photopolymerizable compounds. Examples thereof include monomers, oligomers and polymers. Ethyl acrylate, butyl acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, ethylene glycol dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexa as a photosensitive monomer having a (meth) acryloyl group and an oligomer. Acrylic or methacrylic acid esters of monohydric or polyhydric alcohols such as acrylate, dipentaerythritol hexamethacrylate; polyester prepolymers obtained by condensing polyhydric alcohols with monobasic acids or polybasic acids (meta ) Polyester (meth) acrylate obtained by reacting acrylic acid; (meth) acrylate after reacting a compound having a polyol group and two isocyanate groups Polyurethane (meth) acrylate obtained by reacting phosphoric acid; bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, polycarboxylic acid glycidyl ester, polyol polyglycidyl ester, aliphatic or alicyclic epoxy resin (Meth) acrylate obtained by reacting (meth) acrylic acid with an epoxy resin such as amine, amine epoxy resin, triphenol methane type epoxy resin, dihydroxybenzene type epoxy resin

As photosensitive monomers and oligomers having both a (meth) acryloyl group and a carboxylic acid, bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, polycarboxylic acid glycidyl ester, polyol polyglycidyl Acid anhydrides are added to hydroxy groups obtained by reacting (meth) acrylic acid with epoxy groups such as esters, aliphatic or alicyclic epoxy resins, amine epoxy resins, triphenolmethane type epoxy resins, and dihydroxybenzene type epoxy resins. Reacted epoxy (meth) acrylate carboxylic acid adduct; with a monomer copolymerizable with maleic anhydride, such as ethylene, propene, isobutylene, styrene, vinylphenol, acrylic acid, acrylic ester, acrylamide Compounds obtained by reacting the maleic anhydride portion of the copolymer with an acrylate having an alcoholic hydroxy group such as hydroxyethyl acrylate or an acrylate having an epoxy group such as glycidyl methacrylate to form a half ester; acrylic acid, an acrylic ester and hydroxyethyl A compound obtained by further reacting acrylic acid with -OH group of an acrylate copolymer having an alcoholic hydroxy group such as acrylate:

In addition to the above resins, other resins can be added to the pigment composition of the present invention. Examples of the other resins include film-forming polymer binders. Specific examples of the film-forming polymer binder include, for example, polymethacrylic acid ester or its partial hydrolyzate, polyvinyl acetate or its hydrolyzate, polyvinylphenol, phenol novolak, polystyrene, polyvinyl butyral and polychloroprene. , Polyvinyl chloride, chlorinated polyethylene, chlorinated polypropylene, polyvinylpyrrolidone, copolymer of styrene and maleic anhydride or its half ester, acrylic acid, acrylic acid ester, methacrylic acid, methacrylic acid ester, acrylamide, acrylonitrile, etc. Examples thereof include a copolymer selected from the group of polymerizable monomers and having a glass transition point of 35 ° C. or higher.

A thermopolymerizable resin may be further added to the pigment composition of the present invention. Examples of such thermosetting resin-polymerizable resin include epoxy resin and melamine resin. Among them, as the epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin,
Novolak type epoxy resin, polycarboxylic acid glycidyl ester, polyol polyglycidyl ether, aliphatic or alicyclic epoxy resin, amine epoxy resin, triphenol methane type epoxy resin, dihydroxybenzene type epoxy resin and the like, and also as melamine resin, Examples thereof include polymethylol melamine resin and polymethylol benzoguanamine resin.

As the photopolymerization initiator used in the present invention, various photopolymerization initiators can be used alone or in combination, but generally, a colored photopolymerization property in which a pigment is dispersed in a photopolymerizable resin is used. In the resin, the ultraviolet rays required for the photopolymerization initiator to generate radicals are absorbed by the pigment, and the radicals cannot be sufficiently generated, so that the polymerization tends to be insufficient. Therefore, it is preferable to use a highly sensitive compound or composition as the photopolymerization initiator. Specific examples of such a photopolymerization initiator include benzyl; benzoin ether; benzoin isobutyl ether; benzoin isopropyl ether; benzophenone; benzoylbenzoic acid; methyl benzoylbenzoate.
4-benzoyl-4'-methyldiphenyl sulfide; benzyl methyl ketal; 2-n-butoxyethyl-4-dimethylaminobenzoate; 2-chlorothioxanthone; 2,4-diethylthioxanthone; 2,4-
Diisopropylthioxanthone; Dimethylaminomethylbenzoate; Isoamyl p-dimethylaminobenzoate; 3,3'-Dimethyl-4-methoxybenzophenone;2,4-Dimethylthioxanthone; 1- (4-dodecylphenyl) -2-hydroxy-2- Methylpropan-1-one; 1-hydroxycyclohexyl phenyl ketone; 2-hydroxy-2-methyl-1-phenylpropan-1-one; 1- (4-isopropylphenyl)-
2-Hydroxy-2-methylpropan-1-one; isopropylthioxanthone; methylbenzoylformate; 2-methyl-1- [4- (methylthio) phenyl]
-2-morpholinopropan-1-one, 2,2'-bis (o-chlorophenyl) -4,4 ', 5,5'-tetraphenylbisimidazolyl;2,2'-bis (o-chlorophenyl) ) -4,4 ', 5,5'-Tetra- (p-
Methoxyphenyl) bisimidazolyl. These may be used alone or as a mixture and may be used in an amount of 0.1 to 10% by weight, preferably 0.1
Used in the range of up to 5% by weight.

The solid solution of the pigment in the present invention has a particle size of 1/2 or less of the wavelength of transmitted light, and more preferably 200 nm or less, in view of the necessity of transmitting visible light. is there. The solid solution of the pigment obtained by the above-mentioned method is dispersed with a dispersant or a solvent in a disperser such as a sand mill or a triple roll, or with a resin,
If necessary, the pigment composition for a color filter of the present invention is obtained by kneading with a triple roll or the like in the presence of a dispersant. As the dispersant, those usually used for dispersing pigments can be used. A resin according to the color filter preparation method is further added to the pigment composition for color filter to prepare a resin composition for color filter preparation. Usually, the pigment solid solution is added at a ratio of 10 to 50% by weight with respect to the resin component.

Next, a method for preparing a color filter using the pigment composition for a color filter of the present invention will be described.
The pigment composition of the present invention can be used in any of the usual methods for producing a color filter using a pigment, such as a pigment internal photolithography method, an electrodeposition method, an electric field isel method, and a printing method. For example, in the photolithography method with internal pigment, a pigment composition of the present invention, a photosensitive resin, a photopolymerization initiator, a solvent, a resin composition comprising other components is prepared, and if necessary, treated with an ultrasonic treatment machine or a disperser. After filtering or filtering, it is coated on a substrate such as a glass plate from a spinner coating machine, dried, and then exposed through a photomask using a light source such as an ultra-high pressure mercury lamp, and a pixel is processed through a developing process. To get This operation is usually repeated three times using resin compositions containing pigment solid solutions having different hues to obtain a color filter having pixels of three colors of R, G and B. In the printing method,
An ink composed of the pigment composition of the present invention, a thermosetting resin such as a polyamide resin or an epoxy resin, and a solvent is printed on a substrate such as a glass plate by a printing machine and heat-treated to obtain one pixel. A color filter having pixels of three colors of R, G, and B is obtained by performing such an operation three times by changing the pigment solid solution using the above operation. A color filter using the pigment composition of the present invention can be prepared according to a usual method other than the photolithography method in which the pigment is added and the printing method.

The pigment composition of the present invention is characterized in that the dispersion is stable, and the color filter using this pigment composition has excellent spectral characteristics and a small depolarizing action.

[0025]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Pigment Solid Solution Preparation Example 1 C. I. 40g of Pigment Red 177,
C. I. Pigment Yellow 83 13.
3 g is dissolved in 200 ml concentrated sulfuric acid and stirred at room temperature for 2 hours. This sulfuric acid solution is poured into a large amount of stirred ice water over 1 hour. Then, the mixture was stirred at room temperature for 1 hour, the pigment slurry was filtered, the residue was washed with water until the filtrate became neutral, and then dried at 80 ° C.

Pigment Solid Solution Preparation Examples 2 to 6 Pigment solid solutions comprising the combinations shown in Table 1 below were prepared in the same manner as above.

[0028]

[Table 1] Examples Amount of pigment used 2 CI Pigment Red 177 40.3 g CI Pigment Yellow 185 13.3 g 3 CI Pigment Green 36 45.0 g CI Pigment Yellow 83 83 5.0 g 4 CI Pigment Green 36 45.0 g CI Pigment Yellow 185 10.0 g 5 CI Pigment Blue 15 47.5 g CI Pigment Violet 23 2.5 g 6 CI Pigment Red 208 40.0 g CI Pigment Yellow 83 13.3 g 7 CI Pigment Red 208 40.0 g CI Pigment Yellow 185 13. 3 g

Dispersion Example 1 Pigment solid solution 20 prepared in Pigment Solid Solution Preparation Example 1 above
4 g of sorbitan fatty acid ester compound as a dispersant was added to 7 g of ethyl cellosolve acetate.
6 gr was added and dispersed by a sand mill.

Dispersion Examples 2 to 7 The pigment solid solutions prepared in the above Pigment Solid Solution Preparation Examples 2 to 7 were subjected to a dispersion treatment in the same manner as in Dispersion Example 1.

The average number distribution of particles of the pigment solid solution dispersions obtained in Dispersion Examples 1 to 7 was 200 nm or less.

Example 1 The pigment solid solution dispersion paste obtained in Dispersion Example 1 was
5 g, SMA2625 (styrene-maleic acid half ester) manufactured by Arco Chemical Co., Ltd., 6.5 g of dipentaerythritol hexaacrylate, and Irgacure 369 (photopolymerization initiator) manufactured by Ciba-Geigy Co., Ltd. 0.4
g, Nippon Kayaku Kayakyu DETX (photopolymerization initiator)
And 0.1 g of ethyl cellosolve acetate were mixed and stirred, and further subjected to dispersion treatment by ultrasonic waves for 10 minutes to obtain a pigment composition for a color filter of the present invention.

Examples 2 to 7 In the same manner as in Example 1, the pigment solid solution pigment dispersions of the present invention were obtained using the dispersions of the pigment solid solutions obtained in Dispersion Examples 2 to 7.

Preparation of Pigment Compositions for Comparative Examples 1-7 C.I. I. Pigment Red 177 15g,
C. I. Pigment Yellow 83 5g
4g of sorbitan fatty acid ester compound was added as a dispersant, and ethylcellosolve acetate was added to 76g.
g and dispersed by a sand mill. 15 g of this pigment paste, 6.5 g of SMA2625 (styrene-maleic acid half ester) manufactured by Arco Chemical, 3.5 g of dipentaerythritol hexaacrylate, 0.4 g of Irgacure 369 manufactured by Ciba-Geigy, Nippon Kayaku Kayacure DETX (0.1 g) and ethyl cellosolve acetate (20 g) were mixed, stirred, and subjected to a redispersion treatment with ultrasonic waves for 10 minutes to obtain a pigment composition for a color filter for Comparative Example 1. Pigment compositions 2 to 7 for comparison color filters were dispersed in the same manner as in Comparative Example 1 according to the combination and the amount of use of the pigments shown in Table 1 above.
Got

Examples 8 to 14 The pigment compositions for color filters obtained in Example 1 were
Corning 7059 glass substrate has a dry film thickness of 2
It was applied by a spinner so as to have a thickness of μm and dried. Then, after exposing 100 mj with an ultra-high pressure mercury lamp, 200 ° C
After post-baking for 20 minutes, a color filter having a film thickness of 2 μm was obtained. (Example 8) With respect to the pigment compositions for color filters obtained in Examples 2 to 6, color filters were prepared from each in the same manner as in Example 8. (Examples 9 to 14)

Comparative Examples 1 to 7 Using the pigment compositions obtained in the preparation of the pigment compositions for Comparative Examples 1 to 7 above, color filters for comparison were prepared in the same manner as in Examples 8 to 14. did.

Performance test (1) Measurement of transmittance The transmittance of each of the color filters obtained in Examples 8 to 14 and Comparative Examples 1 to 7 was measured. The results are shown in Table 2.
The transmittance (1) is shown in the column. On the other hand, the compositions obtained in Examples 1 to 6 and the composition for comparison were allowed to stand for 3 months after their preparation, and then the color filters were prepared in the same manner as above using the compositions. The transmittance of the obtained color filter was measured and is shown in the column of transmittance (2) in Table 2. (2) Measurement of Depolarization Deflection The depolarization of the color filters obtained in Examples 8 to 14 and Comparatives 1 to 7 was measured and is shown in Table 2. The depolarization degree was determined by the following method. A color filter is placed between two polarizing plates, and the luminance ratio between when the polarization axes are parallel and when the polarization axes are vertical is defined as the contrast. Then add 2 color filters
When placed between two polarizing plates and when placed outside, the same contrast can be obtained if the color filter has no polarization anomaly (this is called depolarization effect). The degree of depolarization, which represents the degree of depolarization effect, was used. In Table 2, the degree of depolarization is expressed in%.

Table 2 Transmittance measurement wavelength Transmittance (1) Transmittance (2) Depolarization Example 8 610 nm 79.2% 79.1% 81% Comparative Example 1 610 nm 76.5% 68.3% 61% Example 9 610nm 80.3% 80.3% 82% Comparative Example 2 610nm 77.5% 70.1% 60% Example 10 540nm 77.3% 77.3% 80% Comparative Example 3 540nm 74.4% 69.2% 48% Example 11 540nm 78.3% 78.2% 79% Comparative Example 4 540nm 74.8% 69.4% 47% Example 12 450nm 84.0% 83.9% 78% Comparative Example 5 450nm 82.1% 79.8% 48% Example 13 610nm 75.3% 75.3% 82% Comparative Example 6 610nm 74.2% 71.2% 63% Example 14 610nm 76 2% 76.1% 81% Comparative Example 7 610nm 74.8% 69.5% 59%

As is apparent from the table, the pigment composition of the present invention is excellent in dispersion stability, and therefore has the characteristics that the change in transmittance upon standing is extremely small and the depolarization ratio is small.

[0040]

The dispersion stability is good and the spectral characteristics are good.
A pigment composition for a color filter having less depolarizing effect was obtained. In addition, the pigment composition of the present invention can be used in any combination of two or more kinds of pigments, so that the pigment composition having various spectral characteristics can be prepared.

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Claims (15)

[Claims] 1. A pigment composition for a color filter, which is a composition comprising an organic polymer and an organic pigment, wherein the organic pigment is a solid solution of two or more kinds of pigments. 2. The organic polymer is a photosensitive resin comprising a photopolymerizable compound having at least one ethylenically unsaturated double bond, a photopolymerization initiator, and optionally other resins. Item 1. The pigment composition for a color filter according to Item 1. 3. The pigment composition for a color filter according to claim 2, wherein the other resin is a film-forming polymer binder and / or a thermopolymerizable resin. 4. The solid solution of the pigment is CI pigment
The pigment composition for a color filter according to claim 1, which is Red 177 and a yellow pigment. 5. The pigment composition for a color filter according to claim 4, wherein the yellow pigment is a dichlorobenzidine-based disazo pigment. 6. The pigment composition for a color filter according to claim 4, wherein the yellow pigment is an isoindolinone pigment. 7. A solid solution of a pigment is a CI pigment.
Blue 15 and a purple pigment, The pigment composition for color filters of Claim 1 thru | or 3 characterized by the above-mentioned. 8. The pigment composition for a color filter according to claim 7, wherein the purple pigment is a carbazole dioxazine pigment. 9. The color filter pigment composition according to claim 1, wherein the solid solution of the pigment is a compound represented by the following formula (1) and a yellow pigment. (R ₁ , R ₂ , R ₃ and R ₄ each independently represent hydrogen, chlorine or bromine.) 10. The pigment composition for a color filter according to claim 9, wherein the yellow pigment is a dichlorobenzidine-based disazo pigment. 11. The pigment composition for a color filter according to claim 9, wherein the yellow pigment is an isoindolinone pigment. 12. The pigment composition for a color filter according to claim 1, wherein the solid solution of the pigment is a compound represented by the following formula (2) and a yellow pigment. (R ₁ and R ₂ are each independently hydrogen, chlorine, bromine,
An alkoxy group, an alkyl group, a nitro group, a carboanilide group or an alkoxycarbonyl group, and R is a hydrogen atom, a chlorine atom, a bromine atom, an alkoxy group, an alkyl group, a nitro group, a carboanilide group, or an alkoxycarbonyl group, which is substituted by 1 or 2 It represents a substituted phenyl group or a benzimidazolone group. ) 13. The pigment composition for a color filter according to claim 12, wherein the yellow pigment is a dichlorobenzidine-based disazo pigment. 14. The pigment composition for a color filter according to claim 12, wherein the yellow pigment is an isoindolinone pigment. 15. A color filter produced by using the pigment composition for a color filter according to claim 1.