JP2006321979A - Pigment dispersant and its use - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a pigment dispersant that prevents occurrence of foreign matter even in the case of high pigment concentration, an increase in viscosity and a reduction in storage stability and produces a color filter having excellent transparency and color qualities. <P>SOLUTION: The pigment dispersant comprises a compound represented by formula (I). The colored composition for a color filter comprises pigment, the pigment dispersant, a resin-based dispersant and a resin varnish. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a coloring composition for a color filter used for producing a pigment dispersant, a liquid crystal color display, an imaging device, and the like, and a color filter using the same. More specifically, the present invention relates to a coloring composition for a color filter excellent in pigment dispersibility, transparency, fluidity and storage stability, and a color filter using the same.

  Color filters used in liquid crystal displays, etc. are currently applied to a substrate by spin coating, coating, or transfer using a colored composition in which a pigment is dispersed in a photoresist, and then exposed and developed through a photomask. This is mainly produced by a method of forming pixels. At that time, anthraquinone pigments, diketopyrrolopyrrole pigments and condensed azo pigments are usually used as pigments for forming red pixels, but these pigments are dispersed with a normal disperser together with a resin and a solvent. Since the pigment does not disperse sufficiently by simply making it, the dispersion (which may mean “color composition for color filter”) is used to form colored pixels (hereinafter simply referred to as “pixels”) of the color filter. As a result, the resulting red pixel lacked transparency, the pixel had insufficient transmittance as a color filter, and the red pigment was unsatisfactory as a pigment for a color filter coloring composition.

  Further, as a resin generally used for a photoresist, an acrylic polymer having a high acid value is mainly employed because an alkaline aqueous solution can be used as a patterning developer. However, in the pigment dispersion composed of the above-mentioned pigment and a high acid value acrylic resin, aggregation of the pigment particles easily occurs, the viscosity of the pigment dispersion tends to increase, and the viscosity of the pigment dispersion increases with time. Often the storage stability of the dispersion is poor.

  When producing a color filter with a pigment dispersion having the above difficulties, the pigment dispersion to be used is applied and formed on a substrate by a spin coating method, and then the colored film is pixelated. If the pigment has a high viscosity or the pigment is aggregated and the color filter coloring composition shows thixotropic viscosity, the center of the coating layer before pixelation is raised, so a large screen color filter is produced. In some cases, the pixel formed in the central part of the substrate and the pixel formed in the peripheral part cause unevenness in the hue or density difference.

  Therefore, although the coloring composition for color filters (pigment dispersion) is usually in a high concentration range where the pigment concentration is 5 to 20% by mass, the dispersion state is such that the pigment particles are not aggregated with each other. It must be low in viscosity (for example, about 5 to 20 mPa · s) and excellent in storage stability as compared with typical ordinary dry paints and baking paints.

In order to satisfy the above requirements, conventionally, for example, when the red pigment is a diketopyrrolopyrrole pigment (for example, CI Pigment Red 254), the diketopyrrolo having a sulfonation degree of 1 or more per molecule. A method of adding pyrrole sulfonic acid to the pigment or treating the pigment with the sulfonated product has been proposed (Patent Document 1).
JP 2000-160084 A

  On the other hand, liquid crystal display devices have been expanded from monitors for personal computers to color displays for color televisions, and demands for further improvements in color filters have increased, improving pixel transparency and reducing the transmitted light of pixels. There has been a need to increase the contrast ratio and increase the pigment density in the pixel.

  However, in the method using the sulfonated product, it is possible to improve the transparency of the pixel by improving the dispersibility of the pigment, and to prevent an increase in the viscosity of the pigment dispersion and a decrease in storage stability due to an increase in the pigment concentration. It is difficult to control the reaction such as the number of sulfonic acid groups introduced when the pigment is sulfonated, and when a sulfonated product having a large number of sulfonic acid groups introduced is used as a dispersant, the resulting pigment dispersion Aggregates may occur in the inside, and these improvements are desired.

  The present inventors have intensively studied to solve the above-mentioned problems in the color filter coloring composition, and to improve the color quality of the color filter coloring composition, to lower the viscosity, and to prevent the generation of aggregates. As a result, by using a condensed azo compound having a sulfonic acid group as a pigment dispersant, it is possible to reduce the viscosity of the coloring composition for the color filter and to prevent the coloring composition from thickening during storage. It was possible to prevent the generation of aggregates and to improve the transparency of the most important pixel as a color filter, thereby completing the present invention.

The above object is achieved by the present invention described below. That is, this invention provides the pigment dispersant characterized by including the compound represented by the following general formula (I).

The dispersant of the present invention may contain a compound represented by the following general formula (II) and / or the following general formula (III) based on the compound represented by the general formula (I).

（但し、上記一般式（Ｉ）〜（IV）において、Ｘはスルホン酸基を１個以上有しかつ置換基を有していてもよい芳香族環基または複素環基であり、Ｙはスルホン酸基以外の置換基を有していてもよい芳香族環基または複素環基であり、Ｚはスルホン酸基以外の置換基を有していてもよい芳香族環基または複素環基である。） In addition, the present invention provides a disulfonium salt of 1 mol of aromatic amine or heterocyclic amine having at least one sulfonic acid group per 1 mol of the compound represented by the following general formula (IV), Provided is a method for producing a pigment dispersant containing a compound represented by the above general formula (I), wherein 1 mol of an aromatic amine or heterocyclic amine diazonium salt having no acid group is coupled. .

(However, in the above general formulas (I) to (IV), X is an aromatic ring group or a heterocyclic group which has one or more sulfonic acid groups and may have a substituent, and Y is a sulfone group. An aromatic ring group or a heterocyclic group which may have a substituent other than an acid group, and Z is an aromatic ring group or a heterocyclic group which may have a substituent other than a sulfonic acid group .)

  In the present invention, particularly, Y is a 4-sulfophenyl group, X is a 2-chloro-5-trifluoromethylphenyl group or a 2,5-dichlorophenyl group, and Z is other than a sulfonic acid group. It is preferably a phenyl group or a biphenyl group which may have a substituent.

  Moreover, this invention provides the coloring composition for color filters characterized by including the pigment, the pigment dispersant of the said invention, the resin-type dispersing agent, and the resin varnish. Examples of the pigment include soluble and insoluble azo pigments, condensed azo pigments, benzimidazolone pigments, anthraquinone pigments, quinacridone pigments, diketopyrrolopyrrole pigments, perinone pigments, perylene pigments, and dioxazine pigments. Examples thereof include at least one selected from pigments, Ansanthrone pigments, indigo / thioindigo pigments, and phthalocyanine pigments. Particularly preferred pigments are C.I. I. Pigment Red (PR) 254, PR242, PR177, PR122, PR146, PR166, PR224, C.I. I. Pigment violet (PV) 19, PV23, C.I. I. Pigment Blue (PB) 15: 6, PB15: 3 and PB60. The resin dispersant is preferably a cationic resin dispersant.

  Further, the present invention is a method for producing a color filter comprising a step of forming a colored pixel on a color filter substrate, wherein the colored pixel is formed using the colored composition for a color filter of the present invention. And a color filter formed by the method, an image display device equipped with the color filter, and an information transmission device equipped with the image display device.

  According to the present invention, by using a specific pigment dispersant as a dispersant for a color filter, in particular, a color composition for forming red, purple and blue pixels, it is possible to stably produce a color composition for a color filter. It is possible to prevent the formation of agglomerates, and when used as a color filter coloring composition, it has excellent spectral curve characteristics, is crisp and clear, and has a high transparency and light resistance. Color filters having pixels excellent in various fastnesses such as water resistance, heat resistance, solvent resistance, chemical resistance and water resistance can be obtained.

Next, the present invention will be described in more detail with reference to the best mode for carrying out the present invention.
The dispersant of the present invention is characterized by having a condensed azo structure having a sulfonic acid group, and the dispersant of the present invention has excellent affinity for various pigments and can be used for a wide range of pigments. is there. Moreover, since the dispersing agent of this invention has the outstanding pigment dispersion effect, it can be used for manufacture of the coloring composition used for manufacture of a color filter.

  The dispersant containing the compound represented by the general formula (I) of the present invention is preferably produced by the following method. That is, first, an acid chloride of 3-hydroxy-2-naphthoic acid, a diamino aromatic compound or a diamino heterocyclic compound which may have a substituent other than a sulfonic acid group, and an inert solvent such as nitrobenzene The reaction is carried out at 110 to 180 ° C. to produce the compound represented by the general formula (IV). The compound is preferably dissolved and dispersed in alkaline methanol to form a coupling component, and about 1 mol of an aromatic amine or heterocyclic amine (primary amine) having about 1 mol of a sulfonic acid group per 1 mol of the coupling component. Diazotization is carried out by a conventional method, the diazonium compound is coupled, and then about 1 mol of an aromatic amine or heterocyclic amine (secondary amine) which may have a substituent other than a sulfonic acid group is obtained by a conventional method. And can be obtained by coupling the diazonium compound.

  When the secondary amine is first diazotized and coupled in the above method, the yield of the compound represented by the general formula (I) is low. In addition, when the primary amine and the secondary amine are simultaneously diazotized and coupled, the yield of the compound represented by the general formula (I) is low. In the present invention, it is preferable to sequentially diazotize and couple the primary amine and the secondary amine because the production rate of the compound represented by the general formula (I) can be improved.

  The dispersant of the present invention can be obtained by the above method, but the product may contain a small amount of the compound represented by the general formula (II) and / or the general formula (III) (hereinafter referred to as a by-product). However, the product can be used as a pigment dispersant without separating these by-products. The dispersant of the present invention may have a sulfonic acid group that is free or a salt of the sulfonic acid group with a base.

  Examples of the primary amine include o-aminobenzenesulfonic acid, m-aminobenzenesulfonic acid, sulfanilic acid, 2-chloroaniline-3-sulfonic acid, 4-chloroaniline-2-sulfonic acid, and 4-chloroaniline. -3-sulfonic acid, 2,5-dichloroaniline-4-sulfonic acid, 2-nitroaniline-4-sulfonic acid, 2-aminophenol-4-sulfonic acid, o-anisidine-5-sulfonic acid, p-anisidine -5-sulfonic acid, o-toluidine-4-sulfonic acid, m-toluidine-4-sulfonic acid, p-toluidine-2-sulfonic acid, 2-chloro-p-toluidine-3-sulfonic acid, 2-chloro- p-Toluidine-5-sulfonic acid, 4-chloro-m-toluidine-2-sulfonic acid, 3-amino-6-chlorotoluene-4-sulfo Acid, 3-amino-6-chloro-4-sulfobenzoic acid, 1-amino-8-naphthalenesulfonic acid, 2-amino-1-naphthalenesulfonic acid, 4-amino-1-naphthalenesulfonic acid, 5-amino- 1-naphthalenesulfonic acid, 6-amino-1-naphthalenesulfonic acid, 5-amino-3-naphthalenesulfonic acid, 4-amino-5-hydroxy-2,7-naphthalenedisulfonic acid, 1-amino-2-hydroxy- 4-naphthalenesulfonic acid, 6-amino-4-hydroxy-2-naphthalenesulfonic acid, 7-amino-4-hydroxy-2-naphthalenesulfonic acid, 1-amino-2-anthraquinonesulfonic acid, 1-amino-5 Anthraquinone sulfonic acid, 1-amino-8-anthraquinone sulfonic acid, 3-aminocarbazole sulfonic acid, 9-a Roh acridine acid, such as 6-aminoindazole acid. A particularly preferred primary amine is sulfanilic acid.

  Examples of the secondary amine include aniline, toluidine (o-, m- or p-), 2,4-xylidine, 3,4-xylidine, p-cresidine, anisidine (o-, m- or p). -), Aminophenol (o-, m- or p-), anthranilic acid, p-aminobenzoic acid, nitroaniline (o-, m- or p-), chloroaniline (o-, m- or p-) 2,5-dichloroaniline, 3,4-dichloroaniline, 3,5-dichloroaniline, 2,4,5-trichloroaniline, 2-chloro-4-nitroaniline, 5-chloro-2-nitroaniline, 2, , 6-dichloro-4-nitroaniline, o-fluoroaniline, 2,4-difluoroaniline, m-trifluoromethylaniline, 2-chloro-5-trifluoromethylani , 2-aminothiophenol, 2-amino-5-nitrobenzonitrile, 2-amino-3-bromo-5-nitrobenzonitrile, diphenylamine, 1-naphthylamine, 2-naphthylamine, 3-amino-9-ethylcarbazole 2-aminothiazole, 2-amino-5-nitrothiazole, 2-aminobenzothiazole, 2-amino-6-methoxybenzothiazole, 1-aminoanthraquinone, 2-aminoanthraquinone, o- (phenylsulfonyl) aniline, 2 -Ethylsulfonyl-5-trifluoromethylaniline, 4-benzylsulfonyl-o-anisidine, o-anisidine-4-sulfonediethyl amide, o-anisidine-4-sulfonethyl, 6-benzamide-m-4-xylidine, 4 , 4-Dichloro-2-a Bruno diphenyl ether, 4-benzamido-2,5-dimethoxyaniline, 9-amino acridine, such as 6-aminoindazole, and the like. Particularly preferred secondary amines are 2,5-dichloroaniline and 2-chloro-5-trifluoromethylaniline.

  Examples of the diamino aromatic compound used in the production of the compound represented by the general formula (I) include phenylenediamine (o-, m- or p-), 2-chloro-1,4-phenylenediamine, 2-methyl. -1,4-phenylenediamine, 2,5-dichloro-1,4-phenylenediamine, 2,6-dichloro-1,4-phenylenediamine, 2-nitro-1,4-phenylenediamine, 2-cyano-1 , 4-phenylenediamine, 2,5-dimethyl-1,4-phenylenediamine, 2-chloro-5-methyl-1,4-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2, 6-diaminotoluene, 3,4-diaminotoluene, 6-chloro-1,3-phenylenediamine, 5-chloro-1,2-phenylenediamine, 3,4-dia Nobenzoic acid, 3,5-diaminobenzoic acid, 1,5-diaminonaphthalene, 1,8-diaminonaphthalene, 2,3-diaminonaphthalene, 3,3′-dichlorobenzidine, 3,3′-dimethoxybenzidine, 3 , 3′-dihydroxybenzidine, 3,3′-dichloro-4,4′-diaminodiphenylmethane, 4,4′-diamino-3,3′-diethyldiphenylmethane, 4,4′-diaminobenzanilide, 3,5- Diaminochlorobenzene, 4,4′-diaminodiphenyl ether, 3,3′-dimethyl-4,4′-diaminodiphenylmethane, o-tolidine, m-toluylenediamine, bis (4-aminophenyl) sulfide, bis (3-amino Phenyl) sulfone, bis (4-aminophenyl) sulfone, 2,6-diaminopyridine, , 4-di aminopyridine. Particularly preferred diaminoaromatic compounds are phenylenediamine (o-, m- or p-), 2,5-dichloro-1,4-phenylenediamine and 3,3'-dichlorobenzidine.

  Examples of the base when the sulfonic acid group of the compound represented by the general formula (I) is a salt with a base include, for example, alkali metals such as Li, Na, and K; Ca, Ba, Al, Mn, Polyvalent metals such as Sr, Mg and Ni; ammonia; (mono, di or tri) alkylamines, substituted or unsubstituted alkylenediamines, alkanolamines and alkylammonium chlorides.

  The coloring composition for a color filter of the present invention comprises a pigment, the pigment dispersant, a resin dispersant, and a resin varnish. Examples of the red pigment used in the present invention include diketopyrrolopyrrole pigments, anthraquinone pigments, condensed azo pigments, quinacridone pigments, and perylene pigments. Examples of diketopyrrolopyrrole pigments include PR254, anthraquinone pigments such as PR177, condensed azo pigments such as PR242 and PR166, and quinacridone pigments such as PR122, PV19, and perylene pigments. May include PR224. Particularly preferred red pigment is at least one selected from PR254, PR242, PR177, PR122 and PR224.

  These pigments may be used alone or in combination of two or more. At that time, a yellow pigment or the like may be blended for color correction. As such a yellow pigment, an isoindoline pigment (CI pigment yellow (PY) 139), a quinophthalone yellow pigment (PY138), a metal complex pigment (PY150), a disazo yellow pigment (PY83), or the like can be used. . Although the usage-amount of the said red pigment is not specifically limited, Usually, it is used in the ratio of 5-500 mass parts with respect to 100 mass parts of resin binders of the below-mentioned resin varnish.

  The blending ratio of the pigment dispersant to the pigment is preferably 0.05 to 40 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the pigment. If the blending ratio of the dispersant is too small, it is difficult to sufficiently obtain the effect of the intended dispersant. In addition, if the blending ratio of the dispersant is too large, the effect of using only a large amount cannot be obtained, and conversely, the physical properties of the color filter coloring composition obtained as a result are lowered, and furthermore, the dispersant itself has. The hue of the pigment to be dispersed changes greatly depending on the color.

  As the resin dispersant used in the present invention, a known dispersant can be used, and a cationic resin dispersant is particularly preferable. Examples of the cationic resin dispersant include trade names of BYK (Big) Chemie (Germany): DISPER BYK-160, 161, 162, 163, 164, 166, 171 and 182. 184, 2000, 2001, 2070, 2150; EFKA (Netherlands) product names: EFKA-44, 46, 47, 48, 4010, 4050, 4055, 4020, 4015, 4060, 4300, 4330, 4400, 4406, 4510, 4800; trade names of Avecia (UK): SOLSPERS-24000, 32550, NBZ-4204 / 10; Kawaken Fine Chemicals Product name: Hinoact T-6000, 7000, 8000; Ajinomoto Co. product name: Addis Over PB-821, the 822, the 823; Kyoeisha Chemical Co., Ltd. under the trade name: Flowlen DOPA-17HF, same 15BHF, the same 33, such as the 44, and the like.

  The amount of the resin dispersant used in the present invention is not particularly limited, but is preferably 2 to 100 parts by mass, more preferably 10 to 50 parts by mass with respect to 100 parts by mass of the pigment. . When the addition amount of the resin dispersant is less than 2 parts by mass, good pigment dispersion stability cannot be obtained, and when it is more than 100 parts by mass, the developability of the film formed from the colored composition for color filter of the present invention is improved. It may become defective.

  In the present invention, as the resin varnish as a dispersion medium for dispersing the pigment, any known resin varnish conventionally used in coloring compositions for color filters can be used and is not particularly limited. As the dispersion medium, an appropriate solvent or aqueous medium is used as the resin varnish. In addition, conventionally known additives such as a dispersion aid, a smoothing agent, and an adhesive agent are appropriately added and used as necessary.

  As the resin varnish, a photosensitive resin varnish and a non-photosensitive resin varnish are used. Examples of the photosensitive resin varnish include photosensitive resin varnishes used for ultraviolet curable inks and electron beam curable inks. Non-photosensitive resin varnishes include, for example, letterpress ink, planographic ink, intaglio gravure ink, and the like. For resin varnishes used for printing inks such as stencil screen ink, resin varnishes used for inkjet printing, resin varnishes used for electrodeposition coating, resin varnishes used for developers of electronic printing and electrostatic printing, thermal transfer films or ribbons Examples of the resin varnish to be used.

  Specific examples of the photosensitive resin varnish include, for example, photosensitive cyclized rubber resins, photosensitive phenol resins, photosensitive polyacrylate resins, photosensitive polyamide resins, photosensitive polyimide resins, and unsaturated polyesters. Varnishes such as polyester resins, polyester acrylate resins, polyepoxy acrylate resins, polyurethane acrylate resins, polyether acrylate resins, polyol acrylate resins, or varnishes to which monomers are further added as reactive diluents. It is done. As a suitable resin among the photosensitive resin varnish, an alkali-developable acrylate resin having a free carboxylic acid group in the molecule is desirable.

  Specific examples of the non-photosensitive resin varnish include, for example, cellulose acetate resin, nitrocellulose resin, styrene (co) polymer, polyvinyl butyral resin, amino alkyd resin, polyester resin, amino resin modified polyester Resin, polyurethane resin, acrylic polyol urethane resin, soluble polyamide resin, soluble polyimide resin, soluble polyamideimide resin, soluble polyesterimide resin, hydroxyethyl cellulose, styrene-maleic ester copolymer water-soluble salt , (Meth) acrylic acid ester (co) polymer water-soluble salts, water-soluble amino alkyd resins, water-soluble amino polyester resins, water-soluble polyamide resins, and the like. Use in combination It is.

Although the manufacturing method in particular of the coloring composition comprised from said each component of this invention is not restrict | limited, For example, the following method etc. are mentioned.
(A) A method in which a pigment and a pigment dispersant are dissolved in sulfuric acid and the like, and then precipitated in water, both are made into a solid solution, added to a resin varnish together with a cationic resin dispersant, and kneaded.
(B) A cationic resin obtained by uniformly suspending a pigment in water or an organic solvent, adding a solution containing a pigment dispersant to the suspension, and depositing the pigment dispersant on the surface of the pigment particles. A method of kneading in addition to a resin varnish with a dispersant.
(C) A method in which a pigment, a pigment dispersant, and a cationic resin dispersant are finely dispersed by a wet medium dispersing machine such as an attritor or a ball mill, and added to a resin varnish for kneading.
(D) A method in which a pigment, a pigment dispersant, and a cationic resin dispersant are added to a resin varnish at the time of premixing, and the dispersion treatment is performed by a wet medium dispersing machine.

  When producing a color filter using the colored composition for a color filter of the present invention, when a photosensitive resin varnish is used as the resin varnish, a conventionally known photopolymerization such as benzoin ether or benzophenone is used in the composition. A photosensitive coloring composition prepared by adding an initiator and kneaded by a conventionally known method is used. Also, a thermal polymerization initiator is used in place of the above photopolymerization initiator as a thermally polymerizable coloring composition. It can also be used.

  When forming a pixel of a color filter on a substrate using the above photosensitive coloring composition, the photosensitive coloring composition is formed on a transparent substrate, for example, a spin coater, a low-speed rotation coater, a roll coater or a knife coater. The entire surface is coated using various printing methods, or the entire surface printing by various printing methods or partial printing slightly larger than the pixel is performed, and after pre-drying, the photomask is adhered, and exposure is performed using an ultra-high pressure mercury lamp to form the pixel. Bake. Next, development and washing are performed, and post-baking is performed as necessary, so that the color filter pixels can be formed. The color filter pixel forming method itself is known, and in the present invention, the color filter pixel forming method is not particularly limited.

  When forming a color filter pixel using the color filter coloring composition of the present invention (non-photosensitive color composition) using a non-photosensitive resin varnish, the non-photosensitive color composition is formed on a transparent substrate. For example, a method of printing pixels directly on a substrate by the various printing methods described above as a printing ink for a color filter, a method of forming pixels on a substrate by electrodeposition coating as an aqueous electrodeposition coating composition for a color filter, inkjet Use a method of forming pixels on a substrate by ink jet printing as an ink for printing, an electronic printing method or an electrostatic printing method, or form pixels on a transferable substrate by the above method and then transfer them to a color filter substrate The method of doing is mentioned. Then, according to a conventional method, baking is performed as necessary, polishing for smoothing the surface, or top coating for protecting the surface is performed. In addition, a black matrix can be formed according to a conventional method to obtain a color filter having RGB pixels. The manufacturing methods of these color filters are known per se, and the manufacturing method of the color filters is not particularly limited in the present invention.

Next, the present invention will be described more specifically with reference to synthesis examples, examples and comparative examples. In the text, “part” or “%” is based on mass.
[Synthesis Example 1]
According to a conventional method, 60 parts of 3-hydroxy-2-naphthoic acid is acid chlorided in 40 parts of nitrobenzene using 40 parts of thionyl chloride, and 25 parts of 2,5-dichloro-1,4-phenylenediamine is added and added in an amount of 130 to Heat at 135 ° C. for 5 hours. After cooling, 200 parts of methanol was added, filtered, washed with methanol and then with water, and dried to obtain 60 parts of a reaction product.

  100 parts of methanol, 3 parts of sodium hydroxide and 11 parts of sodium acetate trihydrate are added to 10 parts (0.02 mol) of the above reaction product to obtain a submerged solution. 3.5 parts (0.02 mol) of sulfanilic acid was diazotized by a conventional method and coupled to the above-mentioned submerged solution. After 1 hour, 4.3 parts (0.022) of 2-chloro-5-trifluoromethylaniline was obtained. Mole) is diazotized and coupled by a conventional method, and a pigment dispersant mainly composed of a compound represented by the following formula in which one sulfonic acid group is introduced on average per molecule from the result of elemental analysis of sulfur (A) 15 parts were obtained.

The reaction product may contain a small amount of by-products represented by the following formulas, but separation of the by-products represented by these formulas was not necessary.

[Synthesis Example 2]
From the results of elemental analysis of sulfur in the same manner as in Synthesis Example 1 except that 35 parts of 3,3′-dichlorobenzidine is used instead of 25 parts of 2,5-dichloro-1,4-phenylenediamine in Synthesis Example 1. 15 parts of a pigment dispersant (B) having an average of one sulfonic acid group introduced per molecule was obtained.

上記反応生成物中には、下記式で表される副生物が少量含まれている可能性があるが、これらの式で表される副生物の分離は不要であった。

The reaction product may contain a small amount of by-products represented by the following formulas, but separation of the by-products represented by these formulas was not necessary.

[Synthesis Example 3]
According to a conventional method, 60 parts of 3-hydroxy-2-naphthoic acid is acid chlorided using 40 parts of thionyl chloride in 400 parts of nitrobenzene, 17 parts of 1,4-phenylenediamine is added, and the mixture is heated at 130 to 135 ° C. for 5 hours. . After cooling, 200 parts of methanol was added, filtered, washed with methanol and then with water and dried to obtain 57 parts of a reaction product. 100 parts of methanol, 3 parts of sodium hydroxide, and 11 parts of sodium acetate trihydrate are added to 10 parts (0.022 mol) of these to make a submerged solution. 3.9 parts (0.022 mol) of sulfanilic acid was diazotized by a conventional method and coupled to the above-described submerged solution. After 1 hour, 4 parts (0.025 mol) of 2,5-dichloroaniline was prepared by a conventional method. From the result of elemental analysis of sulfur after diazotization and coupling, 16 parts of a pigment dispersant (C) represented by the following formula in which an average of one sulfonic acid group was introduced per molecule was obtained.

上記反応生成物中には、下記式で表される副生物が少量含まれている可能性があるが、これらの式で表される副生物の分離は不要であった。

The reaction product may contain a small amount of by-products represented by the following formulas, but separation of the by-products represented by these formulas was not necessary.

[Example 1]
Acrylic resin varnish (methacrylic acid / butyl acrylate / styrene / hydroxyethyl acrylate copolymerized at a molar ratio of 25/50/15/10, molecular weight 12,000, solid content 30%) 50 parts PR254 20 parts 1 part of the pigment dispersant (A) obtained in Synthesis Example 1, 4 parts of the cationic resin dispersant and 20 parts of a solvent (propylene glycol monomethyl ether acetate) (hereinafter abbreviated as PGMAc) are mixed and premixed. Thereafter, the mixture was dispersed in a horizontal bead mill to obtain a red color filter coloring composition.

[Examples 2 and 3]
Instead of the pigment dispersant (A) of Example 1, the pigment dispersants (B) and (C) obtained in Synthesis Examples 2 and 3 were used, respectively. Two kinds of coloring compositions for red color filters in combination of the described pigment and dispersant were obtained.

[Examples 4 to 6]
Instead of PR254 in Example 1, PR177 was used, and pigment dispersants (A) to (C) obtained in Synthesis Examples 1 to 3 were used, respectively. Three kinds of coloring compositions for red color filters, which are combinations of the pigment and the dispersing agent described in 1 above, were obtained.

[Examples 7 to 9]
In place of PR254 in Example 1, PR242 was used, and pigment dispersants (A) to (C) obtained in Synthesis Examples 1 to 3 were used, respectively. Three kinds of coloring compositions for red color filters, which are combinations of the pigment and the dispersing agent described in 1 above, were obtained.

[Examples 10 to 12]
In place of PR254 in Example 1, PR122 was used, and pigment dispersants (A) to (C) obtained in Synthesis Examples 1 to 3 were used, respectively. Three kinds of coloring compositions for red color filters, which are combinations of the pigment and the dispersing agent described in 1 above, were obtained.

[Examples 13 to 15]
In place of PR254 in Example 1, PR224 was used, and pigment dispersants (A) to (C) obtained in Synthesis Examples 1 to 3 were used, respectively. Three kinds of coloring compositions for red color filters, which are combinations of the pigment and the dispersing agent described in 1 above, were obtained.

[Comparative Examples 1-5]
Except not using a pigment dispersing agent (A), it carried out similarly to Example 1, 4, 7, 10, 13 and obtained the coloring composition for five types of red color filters using the pigment of Table 1. It was.

  The fluidity of the coloring compositions for color filters of the above Examples 1 to 15 and the presence or absence of occurrence of gloss and agglomerates on the color development surface were compared with those in Comparative Examples 1 to 5. The flowability of the coloring composition for the color filter and the observation of the presence or absence of gloss on the color development surface and the occurrence of aggregates were measured according to the following method, and the relative evaluation was made immediately after production and after storage for 1 month at room temperature. Went.

  Flowability (viscosity change): Viscosity (mPa · s) of coloring compositions of Examples and Comparative Examples immediately after production and after storage for 1 month at 25 ° C., using an E-type viscometer, room temperature (25 ° C.), rotor The number of rotations was 6 rpm.

Gross: The colored compositions of Examples and Comparative Examples immediately after production and after storage for 1 month at 25 ° C. were developed on a polypropylene film using a bar coater (coil thickness 0.45 mm), and developed. The surface gloss was compared visually and with a gloss meter. In addition, the thing with high gloss was made favorable, and it displayed with the following parameter | index.
○: Good △: Slightly good ×: Poor

Aggregate observation: The colored compositions of Examples and Comparative Examples immediately after production and after storage for 1 month at 25 ° C. were applied to a glass substrate with a spinner, dried at 90 ° C. for 2 minutes, and then 200 times using a microscope. The presence or absence of aggregates was observed and displayed with the following indices.
○: No aggregate Δ: Slightly aggregate ×: Aggregate The above results are shown in Table 1.

  As apparent from Table 1, the coloring compositions for color filters of Examples 1 to 15 using the pigment dispersants (A) to (C) are the compositions of Comparative Examples 1 to 5 that do not use the pigment dispersant. Compared to the above, the viscosity immediately after production and after storage (after 1 month) is low, the gloss is good, no aggregates are produced immediately after production and after 1 month, and it has excellent properties as a coloring composition for color filters. Was.

[Reference Example 1]
50 parts of acrylic resin varnish used in Example 1, 17 parts of odor chlorinated phthalocyanine green (CI Pigment Green 36), 13 parts of quinophthalone yellow pigment (CI Pigment Yellow 138), monosulfone as a pigment dispersant 2 parts of quinophthalone yellow, 4 parts of a cationic resin dispersant and 20 parts of PGMAc were blended, and after premixing, dispersed with a horizontal bead mill to obtain a green color filter coloring composition.

[Reference Example 2]
As 50 parts of acrylic resin varnish used in Example 1, 16 parts of ε-type copper phthalocyanine blue (CI Pigment Blue 15: 6), 4 parts of dioxazine violet (CI Pigment Violet 23), as a pigment dispersant 2 parts of monosulfonated phthalocyanine blue, 1 part of monosulfonated indanthrone, 4 parts of cationic resin dispersant and 20 parts of PGMAc are mixed, dispersed in a horizontal bead mill after premixing, and colored composition for blue color filter Got.

[Example 16]
In order to produce RGB color filters, colored compositions for R, G and B color filters were obtained according to the formulation shown in Table 2 below.

The glass substrate that had been treated with the silane coupling agent was set on a spin coater, and the colored composition for color filter R in Table 2 was first spin-coated at 300 rpm for 5 seconds and then at 1200 rpm for 5 seconds. Next, prebaking was performed at 80 ° C. for 10 minutes, a photomask having mosaic pixels was brought into close contact, and exposure was performed with an ultrahigh pressure mercury lamp at a light amount of 100 mJ / cm ² . Next, development and washing were performed with a dedicated developer and a dedicated rinse to form red mosaic pixels on the glass substrate. Subsequently, a green mosaic pixel and a blue mosaic pixel are formed by applying and baking according to the above method using the G and B color filter coloring compositions shown in Table 2 and having each RGB pixel. A filter was obtained. The resulting color filter has excellent spectral curve characteristics, excellent fastness such as light resistance and heat resistance of each pixel, and excellent light transmission properties. Excellent properties as a filter.

According to the present invention as described above, by using a specific dispersant as a dispersant for the color filter red color forming composition of the color filter, the color filter color composition can also be stably produced. In addition, when used as a coloring composition for color filters, it has excellent spectral curve characteristics, is clear and crisp, has high transparency, and is light and heat resistant. A color filter having pixels excellent in various fastnesses such as solvent resistance, chemical resistance and water resistance can be obtained.

Claims (11)

A pigment dispersant comprising a compound represented by the following general formula (I):

(However, X in the formula is an aromatic or heterocyclic group which may have one or more sulfonic acid groups and may have a substituent, and Y has a substituent other than a sulfonic acid group. An aromatic ring group or a heterocyclic group which may be substituted, and Z is an aromatic ring group or a heterocyclic group which may have a substituent other than a sulfonic acid group.   Y is a 4-sulfophenyl group, X is a 2-chloro-5-trifluoromethylphenyl group or a 2,5-dichlorophenyl group, and Z has a substituent other than a sulfonic acid group. The pigment dispersant according to claim 1, which may be a phenyl group or a biphenyl group. The pigment dispersant according to claim 1, wherein the compound represented by the general formula (I) is a main component and may contain a compound represented by the following general formula (II) and / or general formula (III).

(However, X in the formula is an aromatic or heterocyclic group which may have one or more sulfonic acid groups and may have a substituent, and Y has a substituent other than a sulfonic acid group. An aromatic ring group or a heterocyclic group which may be substituted, and Z is an aromatic ring group or a heterocyclic group which may have a substituent other than a sulfonic acid group.   Y is a 4-sulfophenyl group, X is a 2-chloro-5-trifluoromethylphenyl group or a 2,5-dichlorophenyl group, and Z has a substituent other than a sulfonic acid group. The pigment dispersant according to claim 3, which is a good phenyl group or biphenyl group. After 1 mol of aromatic amine or heterocyclic amine diazonium salt having at least one sulfonic acid group is coupled per 1 mol of the compound represented by the following general formula (IV), it has no sulfonic acid group. A method for producing a pigment dispersant containing a compound represented by the general formula (I), wherein 1 mol of an aromatic amine or heterocyclic amine diazonium salt is coupled.

(However, Z in the formula is an aromatic ring group or a heterocyclic group which may have a substituent other than the sulfonic acid group.)   A coloring composition for a color filter, comprising a pigment, the pigment dispersant according to claim 1, a resin dispersant, and a resin varnish.   Pigments are soluble / insoluble azo pigments, condensed azo pigments, benzimidazolone pigments, anthraquinone pigments, quinacridone pigments, diketopyrrolopyrrole pigments, perinone pigments, perylene pigments, dioxazine pigments, ansanthrone The coloring composition for a color filter according to claim 6, which is at least one selected from a pigment based on pigment, an indigo / thioindigo pigment and a phthalocyanine pigment. The pigment is C.I. I. Pigment red 254, C.I. I. Pigment red 242, C.I. I. Pigment red 177, C.I. I. Pigment red 122,
C. I. Pigment red 146, C.I. I. Pigment red 166, C.I. I. Pigment red 224, C.I. I. Pigment violet 19, C.I. I. Pigment violet 23, C.I. I. Pigment blue 15: 6, C.I. I. Pigment blue 15: 3 and C.I. I. The coloring composition for a color filter according to claim 6, which is at least one selected from CI Pigment Blue 60.   The coloring composition for a color filter according to claim 6, wherein the resin dispersant is a cationic resin dispersant.   A color filter manufacturing method including a step of forming a colored pixel on a substrate for a color filter, wherein the colored pixel is formed using the colored composition for a color filter according to claim 6. Manufacturing method. A color filter formed by the method according to claim 10.