JP5239462B2 - Thiazine indigo pigment dispersant, pigment composition, coloring composition and color filter using the same - Google Patents

Description

  The present invention relates to a pigment dispersant, a pigment composition, and a coloring composition that are suitably used for printing inks, paints, resin colorants, inkjet inks, color filter inks, and the like. The present invention also relates to a color filter used for a color liquid crystal display device, a color image pickup tube element and the like.

  In printing inks, paints, etc., pigments are dispersed in a fine state to exert a high coloring power, and have appropriate properties such as clear color tone and gloss of printed or coated products. Moreover, the labor and energy at the time of manufacturing printing ink and a coating material can be reduced significantly by dispersing a pigment in a stable state. Furthermore, a dispersion in a stable state is generally excellent in storage stability.

  However, pigments used in printing inks and paints are often fine particles in order to achieve a clearer color tone, and as a result, the cohesion between the pigment particles becomes stronger and the above-mentioned suitability is imparted. Is often difficult.

  In order to solve such problems, it is known to use a pigment dispersant, improve the affinity between the pigment and the vehicle, and stabilize the dispersion. Agents are disclosed.

  For example, a pigment derivative in which a functional group such as an acidic group, a basic group, or a phthalimidomethyl group is introduced into an organic pigment has been developed and has been effective. However, since the pigment derivative has an intrinsic strong color because it uses an organic pigment as a base skeleton, it may be significantly restricted when used for a pigment having a different hue.

  For example, in a system that disperses highly fine pigment particles such as printing inks, paints, especially ink jet inks, color filter inks, etc., it is used to relieve the strong cohesive force of the pigment particles and obtain stability over time. There is a tendency to increase the amount of the pigment dispersant, which has a dilemma that adversely affects the sharpness.

In addition, when different types of pigments are mixed and dispersed, or when inks made of different types of pigments are mixed, there is a phenomenon such as thickening, color separation and sedimentation that could not occur with a single pigment. It may cause uneven color and a marked decrease in coloring power.
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An object of the present invention is to provide a pigment dispersant that exhibits a dispersion performance for a wide range of pigments while exhibiting high sharpness.
Another object of the present invention is to provide a pigment composition that realizes high definition and exhibits excellent dispersion performance with respect to the pigment carrier.
Furthermore, the present invention is excellent in fluidity, storage stability, and gloss when formed into a dry film while having high sharpness, and is suitably used as printing ink, paint, inkjet ink, color filter ink, and the like. An object is to provide a coloring composition.

The trans-thiazineindigo pigment dispersant of the present invention is a compound represented by the following formula (1).
Moreover, the cis-type thiazine indigo pigment dispersant of the present invention is a compound represented by the following formula (2).

In the formula, R ₁ and R ₂ each independently represent a group necessary for forming an optionally substituted aromatic or aliphatic carbocyclic ring or heterocyclic ring. Y is a direct bond, —O—, —S (O) m— (where m represents an integer of 0 to 3), —CO—, —NR ₃ —, —CONR ₃ —, —NR ₃ CO _{-, - NR 3 SO 2 -} , - SO 2 NR 3 - ( wherein _{R 3} represents a hydrogen atom, an alkyl group or hydroxyalkyl group,), or an alkylene group and a straight-chain or branched having 1 to 12 carbon atoms , An alkyl group, an amino group, a nitro group, a hydroxyl group, an alkoxy group, a benzene residue or a triazine residue which may be substituted with a halogen atom, or a linking group obtained by combining two or more of these linking groups. M ^{n +} represents a hydrogen ion, a metal ion, or an ammonium ion at least one of which is substituted with an alkyl group, n represents the valence of M, and represents an integer of 1 to 3. p and q are numbers from 0 to 4, and the sum of p and q is from 1 to 4.

The pigment composition of the present invention is characterized by containing the pigment and the trans-type or cis-type thiazine indigo pigment dispersant of the present invention.
The coloring composition of the present invention is characterized by containing the pigment composition of the present invention and a pigment carrier.
Moreover, the color filter of this invention comprises the filter segment formed from the coloring composition of this invention, It is characterized by the above-mentioned.

By using the thiazine indigo pigment dispersant of the present invention, it is possible to finely disperse the pigment in a wide range of resins, non-aggregation, non-crystallinity, fluidity, coating gloss, sharpness, storage Good inks and paints excellent in stability can be easily obtained.
In particular, the thiazine indigo pigment dispersant of the present invention is excellent in dispersion while exhibiting high sharpness in red pigment groups such as diketopyrrolopyrrole red pigments, quinacridone red pigments and anthraquinone red pigments. Demonstrate.

  The coloring composition containing the thiazine indigo pigment dispersant of the present invention includes gravure inks, various general paints for automobiles, woods, metals, etc., back coat paints for magnetic tapes, radiation cure inks, inks for inkjet printers It can be used for applications such as color filter inks.

  First, the trans-thiazine indigo pigment dispersant and cis-thiazine indigo pigment dispersant of the present invention will be described.

  The trans type thiazine indigo pigment dispersant of the present invention is a compound represented by the above formula (1), and the cis type thiazine indigo pigment dispersant is a compound represented by the above formula (2).

  Among the trans-thiazine indigo pigment dispersant of the present invention and the cis-thiazine indigo pigment dispersant of the present invention, preferred pigment dispersants are the following conditions in the above formula (1) and the above formula (2). It is a compound with a structure satisfying.

R ₁ and R ₂ are independently of each other halogen, nitro, cyano, trifluoromethyl, carbonamido, alkyl, alkoxy, amino, alkylamino, thioalkyl, phenoxy, phenylamino, phenylthio, acyl, acyloxy, acylamine An aromatic carbocycle substituted with an aryl group or the like is shown. Y is a direct bond, —O—, —S (O) m— (where m represents an integer of 0 to 3), —CO—, —NR ₃ —, —CONR ₃ —, —NR ₃ CO —, —NR ₃ SO ₂ —, —SO ₂ NR ₃ — (wherein R ₃ represents a hydrogen atom, an alkyl group, or a hydroxyalkyl group), a linear or branched alkylene group having 1 to 6 carbon atoms, or , An alkyl group, an amino group, a nitro group, a hydroxyl group, an alkoxy group, a benzene residue or a triazine residue which may be substituted with a halogen atom, or a linking group obtained by combining two or more of these linking groups. M ^{n +} represents a hydrogen ion, a metal ion, or an ammonium ion at least one of which is substituted with an alkyl group, n represents the valence of M, and represents an integer of 1 to 3. p and q are numbers from 0 to 2, and the sum of p and q is 0 to 2.

  In one embodiment, the thiazine indigo moiety in the trans-thiazine indigo pigment dispersant of the present invention is represented by formula (A).

  In one embodiment, the thiazine indigo moiety in the cis-type thiazine indigo pigment dispersant of the present invention is represented by the formula (B).

  The thiazine indigo pigment dispersant of the present invention takes cis-type and trans-type isomers derived from the pigment skeleton, and both the trans-type and the cis-type have excellent sharpness, but the trans-type has further excellent viscosity characteristics. Therefore, it is preferable. When dispersing the pigment, the composition of the trans type is 50 to 100% by weight and the cis type is 50 to 0% by weight, based on the total weight (100% by weight) of the cis type pigment dispersant and the trans type pigment dispersant. It is preferable to use at a composition ratio of 80 to 100% by weight for the trans type and 20 to 0% by weight for the cis type, and it is particularly preferable to use only the trans type.

Next, the pigment composition of the present invention will be described.
The pigment composition of the present invention contains a pigment and a trans-type or cis-type thiazine indigo pigment dispersant of the present invention.

  As the pigment contained in the pigment composition of the present invention, various commercially available organic pigments or inorganic pigments can be used.

  Examples of organic pigments include azo, anthanthrone, anthrapyrimidine, anthraquinone, isoindolinone, isoindoline, indanthrone, quinacridone, quinophthalone, dioxazine, diketopyrrolopyrrole, Organic pigments such as thiazine indigo, thioindigo, pyranthrone, phthalocyanine, flavanthrone, perinone, perylene, benzimidazolone and the like can be mentioned. Examples of the inorganic pigment include carbon black, titanium oxide, yellow lead, cadmium yellow, cadmium red, dial, iron black, zinc white, bitumen, and ultramarine blue. These pigments may be used in combination.

  Among the pigments, non-aggregation, non-crystallinity, fluidity, and the like are significant for pigments having the same or similar chemical structure as the thiazine indigo pigment dispersant of the present invention. In terms of hue, it is preferably used for yellow to red pigments, and more preferably for orange to red pigments.

  In particular, since the pigment dispersant of the present invention exhibits an excellent dispersion effect while maintaining the color of the pigment itself and maintaining high sharpness, diketopyrrolopyrrole red pigment, quinacridone red pigment, thiazine It is preferably used for red pigments represented by indigo red pigments and anthraquinone red pigments.

  0.1-30 weight part is preferable with respect to 100 weight part of pigments, and, as for the quantity of the thiazine indigo pigment dispersant of this invention contained in a pigment composition, 1-20 weight part is more preferable. When the content of the thiazine indigo pigment dispersant of the present invention is less than 0.1 parts by weight, it is difficult to obtain the effect of the added thiazine indigo pigment dispersant. In addition, the difference between the physical properties of the obtained pigment composition and the physical properties of the pigment alone may become large, and problems in practical quality may occur when used in inks and paints.

  The pigment composition of the present invention can provide a sufficient dispersion effect by simply mixing and adjusting the pigment powder and the thiazineindigo pigment dispersant powder of the present invention, but it is even better if adjusted by the following method. Results can be obtained. As a method for adjusting the pigment composition other than the powder mixing, a pigment powder and a powder of the pigment dispersant of the present invention using a dissolver, a high speed mixer, a homomixer, a kneader, a roll mill, an attritor, a sand mill, various pulverizers, etc. A method of mechanically mixing, adding a solution containing the pigment dispersant of the present invention to a suspension system of pigment water or an organic solvent, and depositing the pigment dispersant on the pigment surface, having a strong dissolving power such as sulfuric acid Examples thereof include a method in which an organic pigment and a pigment dispersant are co-dissolved in a solvent and coprecipitated with a poor solvent such as water.

Next, the coloring composition of this invention is demonstrated.
The coloring composition of the present invention contains the pigment composition of the present invention and a pigment carrier. The pigment carrier is constituted by a resin, its precursor or a mixture thereof. When producing a color filter using the colored composition of the present invention, a transparent resin having a transmittance of 80% or more, particularly 95% or more in the entire wavelength region of 400 to 700 nm in the visible light region is used as the resin. Is preferred.

  Examples of the resin include thermoplastic resins, thermosetting resins, and photosensitive resins. Examples of the resin precursor include monomers or oligomers that are cured by irradiation with radiation to form a resin, and these can be used alone or in combination of two or more.

  The pigment carrier can be used in an amount of 30 to 700 parts by weight, preferably 60 to 450 parts by weight, with respect to 100 parts by weight of the pigment composition in the coloring composition. When a mixture of a resin and its precursor is used as a pigment carrier, the resin is 20 to 400 parts by weight, preferably 50 to 250 parts by weight with respect to 100 parts by weight of the pigment composition in the colored composition. Can be used. The resin precursor can be used in an amount of 10 to 300 parts by weight, preferably 10 to 200 parts by weight, with respect to 100 parts by weight of the pigment composition in the colored composition.

  Examples of the thermoplastic resin include butyral resin, styrene-maleic acid copolymer, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, polyurethane resin, and polyester resin. , Acrylic resins, alkyd resins, polystyrene, polyamide resins, rubber resins, cyclized rubber resins, celluloses, polyethylene, polybutadiene, polyimide resins, and the like.

  Examples of the thermosetting resin include epoxy resins, benzoguanamine resins, rosin-modified maleic acid resins, rosin-modified fumaric acid resins, melamine resins, urea resins, and phenol resins.

  Photosensitive resins include (meth) acrylic compounds and silicate polymers having reactive substituents such as isocyanate groups, aldehyde groups, and epoxy groups on polymers having reactive substituents such as hydroxyl groups, carboxyl groups, and amino groups. A resin obtained by reacting an acid and introducing a photocrosslinkable group such as a (meth) acryloyl group or a styryl group into the polymer 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 products are also used.

  As monomers and oligomers that are precursors of resins, methyl (meth) acrylate, ethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, cyclohexyl (meth) acrylate, β- Carboxyethyl (meth) acrylate, polyethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, trimethylolpropane tri ( (Meth) acrylate, pentaerythritol tri (meth) acrylate, 1,6-hexanediol diglycidyl ether di (meth) acrylate, bisphenol A diglycidyl ether di (meth) Acrylate, neopentyl glycol diglycidyl ether di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tricyclodecanyl (meth) acrylate, ester acrylate, (meth) acrylic acid ester of methylolated melamine, epoxy (meth) Various acrylates and methacrylates such as acrylate and urethane acrylate, (meth) acrylic acid, styrene, vinyl acetate, hydroxyethyl vinyl ether, ethylene glycol divinyl ether, pentaerythritol trivinyl ether, (meth) acrylamide, N-hydroxymethyl ( Examples include meth) acrylamide, N-vinylformamide, acrylonitrile and the like.

  In order to improve the dispersibility of the pigment in the pigment carrier, the coloring composition according to the present invention may appropriately contain a dispersion aid such as a surfactant or a resin-type pigment dispersant. The dispersion aid can be used in an amount of 0.1 to 40 parts by weight, preferably 0.1 to 30 parts by weight, with respect to 100 parts by weight of the pigment composition in the coloring composition.

  Surfactants include polyoxyethylene alkyl ether sulfate, sodium dodecylbenzenesulfonate, alkali salt of styrene-acrylic acid copolymer, sodium alkylnaphthalenesulfonate, sodium alkyldiphenyletherdisulfonate, lauryl sulfate monoethanolamine, lauryl Anionic surfactants such as triethanolamine sulfate, ammonium lauryl sulfate, monoethanolamine stearate, sodium stearate, sodium lauryl sulfate, monoethanolamine of styrene-acrylic acid copolymer, polyoxyethylene alkyl ether phosphate; Polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene Nonionic surfactants such as alkyl ether phosphates, polyoxyethylene sorbitan monostearate, and polyethylene glycol monolaurate; chaotic surfactants such as alkyl quaternary ammonium salts and their ethylene oxide adducts; alkyldimethylamino Examples include amphoteric surfactants such as alkylbetaines such as betaine acetate and alkylimidazolines, and fluorine-based and silicon-based surfactants.

  Resin-type pigment dispersant is a resin that has a pigment-affinity part that has the property of adsorbing to the pigment and a part that is compatible with the pigment carrier, and adsorbs to the pigment to stabilize the dispersion of the pigment on the pigment carrier It works to do. Examples of the resin-type pigment dispersant include those made of a polyester-based, acrylic-based, or urethane-based linear or comb-like resin. The main chain or terminal of the linear resin, the main chain or side of the comb-shaped resin, and the like. Those having a basic group, acidic group, aromatic group or the like in the chain in a block or randomly are preferable.

  Examples of commercially available resin-type pigment dispersants include, for example, Polyflow No. 75, NO. 90, NO. 95 (manufactured by Kyoeisha Yushi Chemical Co., Ltd.), MegaFuck F171, F172, F173 (manufactured by Dainippon Ink and Chemicals), and Florard FC430. , FC431 (manufactured by Sumitomo 3M), various Solsperse dispersants (manufactured by Avicia) such as Solsperse 13240, 20000, 24000, 26000, 28000, Dispersic 111, 160, 161, 162, 163, 164, 170, 182, 2000, 2001 Dispersic dispersants (made by BYK Chemie), etc., Ajisper PB711, PB411, PB111, PB814, PB821, PB822, and other various adipar dispersants (manufactured by Ajinomoto Fine-Techno), Fuka dispersants such as Fuka 46 and 47 Chemicals Co., Ltd.), and the like.

  When the colored composition of the present invention is cured by irradiation with light such as ultraviolet rays, a photopolymerization initiator is added.

  Examples of photopolymerization initiators include 4-phenoxydichloroacetophenone, 4-T-butyl-dichloroacetophenone, diethoxyacetophenone, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- Acetophenone photopolymerization initiators such as hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl Benzoin photopolymerization initiators such as ether and benzyldimethyl ketal, benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4-benzene Benzophenone-based photopolymerization initiators such as zoyl-4′-methyldiphenyl sulfide, thioxanthone-based light such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone Polymerization initiator, 2,4,6-trichloro-S-triazine, 2-phenyl-4,6-bis (trichloromethyl) -S-triazine, 2- (P-methoxyphenyl) -4,6-bis (trichloro) Methyl) -S-triazine, 2- (P-tolyl) -4,6-bis (trichloromethyl) -S-triazine, 2-piperonyl-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, 2,4-trichloromethyl- (piperonyl) -6-triazine , 2,4-trichloromethyl (4′-methoxystyryl) -6-triazine and other triazine photopolymerization initiators, borate photopolymerization initiators, carbazole photopolymerization initiators, imidazole photopolymerization initiators and the like are used. It is done. A photoinitiator can be used in the amount of 5-200 weight part with respect to 100 weight part of pigment compositions in a coloring composition, Preferably it is 10-150 weight part.

  The above photopolymerization initiators can be used alone or in combination of two or more. As the sensitizer, α-acyloxime ester, acylphosphine oxide, methylphenylglyoxylate, benzyl, 9,10- Phenanthrenequinone, camphorquinone, ethylanthraquinone, 4,4'-diethylisophthalophenone, 3,3 ', 4,4'-tetra (T-butylperoxycarbonyl) benzophenone, 4,4'-diethylaminobenzophenone These compounds can also be used in combination. The sensitizer can be used in an amount of 0.1 to 60 parts by weight with respect to 100 parts by weight of the photopolymerization initiator in the colored composition.

  The coloring composition of the present invention can contain a solvent in order to facilitate the dispersion of the pigment in the pigment carrier and the formation of a uniform coating film. Examples of the solvent include cyclohexanone, propylene glycol diacetate, propylene glycol monomethyl ether, diethylene glycol diethyl ether, methyl isobutyl ketone, N-butyl alcohol, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, propylene glycol monopropyl ether, dipropylene. Glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monomethyl butyl ether, propylene glycol phenyl ether, dipropylene glycol monomethyl ether acetate, 1,3-butylene glycol diacetate, ethylene glycol monobutyl ether, ethylene Glycol monobutyl ether acetate, diethylene glycol monobutyl ether, diethylene glycol monobutyl ether acetate, 3-methoxybutanol, 1,3-butylene glycol, triacetin, 3,3,5-trimethyl-2-cyclohexen-1-one, ethylene glycol monoethyl ether , Γ-butyrolactone, isoamyl acetate, ethyl 3-ethoxypropionate, propylene glycol monomethyl ether acetate, toluene, O-xylene, M-xylene, P-xylene, methyl 3-methoxypropionate, butyl acetate, isobutyl acetate, propyl acetate Etc. These solvents can be used alone or in combination.

  The solvent can be used in a total amount of 800 to 4000 parts by weight, preferably 1000 to 2500 parts by weight, based on 100 parts by weight of the pigment composition in the coloring composition.

  The colored composition of the present invention can contain a storage stabilizer in order to stabilize the viscosity of the composition over time. Moreover, in order to improve adhesiveness with a base material, adhesion improving agents, such as a silane coupling agent, can also be contained.

  In addition, the coloring composition of the present invention, if necessary, within a range not impairing the effects of the present invention, a thermal polymerization inhibitor, a plasticizer, a surface protective agent, a smoothing agent, a coating aid, an adhesion improver, a coating Additives such as property improvers or development improvers can be added.

  The coloring composition of the present invention comprises a three-roll mill, a two-roll mill, a horizontal sand mill in the pigment carrier and an organic solvent, together with the dispersion aid and the photopolymerization initiator as necessary. It can be produced by finely dispersing using various dispersing means such as a vertical sand mill, an annular bead mill, a kneader, and an attritor. In addition, a coloring composition containing two or more kinds of pigments is produced by mixing each pigment separately finely dispersed in a pigment carrier and an organic solvent using the thiazine indigo pigment dispersant of the present invention. You can also.

  The colored composition of the present invention may be dispersed after mixing all the components constituting the colored composition. First, the pigment and the thiazine indigo pigment dispersant of the present invention are mixed with a resin and / or an organic solvent. It is preferable to disperse in a part, and then add and disperse the remaining components.

  Also, before dispersing with horizontal sand mill, vertical sand mill, annular bead mill, attritor, etc., pre-dispersion using knitted meat mixer such as kneader, three roll mill, solid dispersion with two roll mill, etc., or pigment The thiazine indigo pigment dispersant may be treated. In addition, after being dispersed by a bead mill or the like, a post-treatment called aging which is stored at a temperature of 30 to 80 ° C. for several hours to one week, or a post-treatment using an ultrasonic disperser or a collision type beadless disperser is performed. When done, it is effective for the stability of the colored composition. In addition, any disperser or mixer such as a microfluidizer, high speed mixer, homomixer, ball mill, roll mill, stone mill, or ultrasonic disperser can be used to produce the colored composition of the present invention.

  When the colored composition of the present invention is used for the production of a color filter, the coarse particles of 5 μM or more, preferably 1 μM or more, more preferably, by means of centrifugation, sintered filter, membrane filter or the like. It is preferable to remove coarse particles of 0.5 μM or more and mixed dust.

  The coloring composition of the present invention can be prepared as gravure offset printing ink, waterless offset printing ink, silk screen printing ink, solvent development type or alkali development type colored resist material.

  The solvent development type or alkali development type colored resist material contains a thermoplastic resin, thermosetting resin or photosensitive resin as a pigment carrier, a monomer, a photopolymerization initiator, and a solvent. The pigment composition of the invention is dispersed.

  Furthermore, the colored composition of the present invention is excellent in dispersion effect and stability over time even in the coloring of a wide range of printing inks, paints, inkjet inks, and plastics, and a colored product having coloring power can be obtained.

  In that case, without using a monomer or photopolymerization initiator, in addition to the resins and solvents described above, resins such as petroleum resin, casein, shellac, drying oil, synthetic drying oil, and ethyl cellosolve acetate, butyl cellosolve acetate, ethylbenzene, acetic acid Using a solvent such as ethyl, methanol, ethanol, isopropyl alcohol, butanol, ethylene glycol, glycerin, dimethylformamide, Solvesso 100 (Exxon Chemical Co., Ltd.), Swazol 1000, petroleum-based solvent, etc., if necessary, a surfactant and / or A colored composition can be produced by the above-described method using a resin-type pigment dispersant.

Next, the color filter will be described.
The color filter of the present invention is a filter in which three color filter segments of R (red), G (green), and B (blue) are formed on a transparent or reflective substrate, Y (yellow), and M (magenta). , C (cyan) three-color filter segments, and the like. Each color filter segment can be formed by using the coloring composition of the present invention by a printing method or a photolithography method.

  As the transparent substrate, a glass plate such as quartz glass, borosilicate glass, alumina silicate glass, soda lime glass whose surface is coated with silica, or a resin plate such as polycarbonate, polymethyl methacrylate, or polyethylene terephthalate is used.

  As the reflective substrate, silicon or a substrate obtained by forming an aluminum, silver, silver / copper / palladium alloy thin film on the transparent substrate is used.

  The formation of each color filter segment by the printing method can be patterned simply by repeating the printing and drying of the colored composition prepared as the above various printing inks. Therefore, the color filter manufacturing method is low-cost and excellent in mass productivity. ing. Furthermore, it is possible to print a fine pattern having high dimensional accuracy and smoothness by the development of printing technology. In order to perform printing, it is preferable that the ink does not dry and solidify on the printing plate or on the blanket. Control of ink fluidity on a printing press is also important, and ink viscosity can be adjusted with a dispersant or extender pigment.

  When forming each color filter segment by a photolithography method, the colored composition prepared as the solvent developing type or alkali developing type colored resist material is applied on a transparent substrate, such as spray coating, spin coating, slit coating, roll coating, etc. Depending on the coating method, the dry film thickness is 0. Apply to 2-5 μm. If necessary, the dried film is exposed to ultraviolet light through a mask having a predetermined pattern provided in contact with or non-contact with the film. Then, after immersing in a solvent or an alkaline developer, or spraying the developer with a spray or the like to remove the uncured portion to form a desired pattern, the same operation is repeated for other colors to produce a color filter. be able to. Furthermore, in order to accelerate the polymerization of the colored resist material, heating can be performed as necessary. According to the photolithography method, a color filter with higher accuracy than the above printing method can be manufactured.

  In development, an aqueous solution such as sodium carbonate or sodium hydroxide is used as an alkali developer, and an organic alkali such as dimethylbenzylamine or triethanolamine can also be used. Moreover, an antifoamer and surfactant can also be added to a developing solution.

  In order to increase the UV exposure sensitivity, after coating and drying the colored resist material, a water-soluble or alkali-soluble resin such as polyvinyl alcohol or a water-soluble acrylic resin is applied and dried to form a film that prevents polymerization inhibition by oxygen. Thereafter, ultraviolet exposure can also be performed.

  The color filter of the present invention can be produced by an electrodeposition method, a transfer method, or the like in addition to the above method, but the colored composition of the present invention can be used in any method. The electrodeposition method is a method for producing a color filter by using a transparent conductive film formed on a transparent substrate and forming each color filter segment on the transparent conductive film by electrophoresis of colloidal particles. is there.

  The transfer method is a method in which a color filter layer is formed in advance on the surface of a peelable transfer base sheet, and this color filter layer is transferred to a desired transparent substrate.

  If a black matrix is formed in advance before forming the filter segment on the transparent substrate or the reflective substrate, the contrast ratio of the liquid crystal display panel can be further increased. As the black matrix, a multilayer film of chromium, chromium / chromium oxide, an inorganic film such as titanium nitride, or a resin film in which a light shielding agent is dispersed is used, but is not limited thereto. In addition, a thin film transistor (TFT) may be formed in advance on the transparent substrate or the reflective substrate, and then a filter segment may be formed. By forming the filter segment on the TFT substrate, the aperture ratio of the liquid crystal display panel can be increased and the luminance can be improved.

  On the color filter of the present invention, an overcoat film, a columnar spacer, a transparent conductive film, a liquid crystal alignment film, and the like are formed as necessary.

  The color filter is bonded to the counter substrate using a sealant, and after injecting liquid crystal from the injection port provided in the seal part, the injection port is sealed, and if necessary, a polarizing film or a retardation film is placed outside the substrate. A liquid crystal display panel is manufactured by bonding.

  Such a liquid crystal display panel includes a twisted nematic (TN), a super twisted nematic (STN), an in-plane switching (IPS), a vertical alignment (VA), an optical conven- It can be used in a liquid crystal display mode in which colorization is performed using a color filter such as Send Bend (OCB).

  Hereinafter, the present invention will be described by way of examples. In the examples, parts represent parts by weight.

<Example 1 (Synthesis of Pigment Dispersant A)>
In 100 parts of sulfuric acid, 10 parts of cis-thiazineindigo pigment was charged at room temperature. After stirring for 3.5 hours, it was added dropwise to 1500 parts of cold acetone. The precipitated compound was filtered and washed with 3000 parts of ice water. After drying at 80 ° C., 4 parts of pigment dispersant A represented by the following formula was obtained.

<Example 2 (Synthesis of Pigment Dispersant B)>
In a 200 mL four-necked flask, 100 parts of N, N-dimethylformamide and 20 parts of pigment dispersant A synthesized in Example 1 were charged, stirred at 150 ° C. for 3 hours, and then added dropwise to 400 parts of water. The product was filtered, washed with water and dried at 80 ° C. As a result, 18 parts of pigment dispersant B represented by the following formula was obtained.

(Adjustment of red processed pigment)
Diketopyrrolopyrrole (hereinafter referred to as DPP) -based red pigment (CI. PIGMENT RED 254, “IRGAPHOR RED B-CF” manufactured by Ciba Specialty Chemicals Co., Ltd.), 1500 parts of sodium chloride, and diethylene glycol 150 Part of the mixture was kneaded at 120 ° C. for 2 hours using a stainless steel 1 gallon kneader (Inoue Seisakusho). Next, this kneaded material was put into 5 liters of warm water and stirred for 1 hour while heating to 70 ° C. to form a slurry. Filtration and washing were repeated to remove sodium chloride and diethylene glycol, followed by drying at 80 ° C. for a whole day and night to obtain 290 parts of a red-treated pigment.

  The red-treated pigment, the pigment dispersant acrylic resin solution, and the solvent (cyclohexanone) were weighed in a 140 ml screw cap bottle with the blending amounts shown in Table 1, respectively. 150 g of zirconia beads having a diameter of 1.25 mm were added and dispersed for 10 hours with a paint conditioner to obtain a colored composition.

(Evaluation of coloring composition)
The viscosity and thixo index value (TI value) of the coloring composition were measured with a B-type viscometer at 25 ° C.
Furthermore, after storing the colored composition at 40 ° C. for 1 week, the viscosity was measured with a B-type viscometer at 25 ° C.

Viscosity stability over time ◎, (There is almost no thickening), ○ (Slight thickening is seen but usable range), △ (Thickening is seen and cannot be used), × (Unusable due to significant thickening) It was expressed in four stages.
In addition, three glass substrates are prepared, and the dispersion paste is dropped, and spin coating is applied for 6 seconds at 550 rpm, 650 rpm, and 750 rpm, respectively, followed by drying at 80 ° C. for 10 minutes. And three coating films having different rotational speeds were formed.

These substrates were subjected to color measurement using a Hitachi spectrophotometer U3310 (manufactured by Hitachi High-Technology Corporation), and the sharpness (Y value) and chromaticity (x, y value) in the CIE color system were evaluated.
These results are summarized in Table 1.

  As shown in Table 1, those using the pigment dispersant of the present invention showed improved sharpness, further excellent fluidity, and good viscosity stability over time.

Claims (8)

A trans-thiazine indigo pigment dispersant represented by the following formula (1).

In the formula, R ₁ and R ₂ each independently represent a group necessary for forming an optionally substituted aromatic or aliphatic carbocyclic ring or heterocyclic ring. Y is a direct bond, —O—, —S (O) m— (where m represents an integer of 0 to 3), —CO—, —NR ₃ —, —CONR ₃ —, —NR ₃ CO _{-, - NR 3 SO 2 -} , - SO 2 NR 3 - ( wherein _{R 3} represents a hydrogen atom, an alkyl group or hydroxyalkyl group,), or an alkylene group and a straight-chain or branched having 1 to 12 carbon atoms , An alkyl group, an amino group, a nitro group, a hydroxyl group, an alkoxy group, a benzene residue or a triazine residue which may be substituted with a halogen atom, or a linking group obtained by combining two or more of these linking groups. M ^{n +} represents a hydrogen ion, a metal ion, or an ammonium ion at least one of which is substituted with an alkyl group, n represents the valence of M, and represents an integer of 1 to 3. p and q are numbers from 0 to 4, and the sum of p and q is from 1 to 4.
A cis-type thiazine indigo pigment dispersant represented by the following formula (2).


In the formula, R ₁ and R ₂ each independently represent a group necessary for forming an optionally substituted aromatic or aliphatic carbocyclic ring or heterocyclic ring. Y is a direct bond, —O—, —S (O) m— (where m represents an integer of 0 to 3), —CO—, —NR ₃ —, —CONR ₃ —, —NR ₃ CO _{-, - NR 3 SO 2 -} , - SO 2 NR 3 - ( wherein _{R 3} represents a hydrogen atom, an alkyl group or hydroxyalkyl group,), or an alkylene group and a straight-chain or branched having 1 to 12 carbon atoms , An alkyl group, an amino group, a nitro group, a hydroxyl group, an alkoxy group, a benzene residue or a triazine residue which may be substituted with a halogen atom, or a linking group obtained by combining two or more of these linking groups. M ^{n +} represents a hydrogen ion, a metal ion, or an ammonium ion at least one of which is substituted with an alkyl group, n represents the valence of M, and represents an integer of 1 to 3. p and q are numbers from 0 to 4, and the sum of p and q is from 1 to 4.
  A pigment composition comprising the pigment and the trans-thiazine indigo pigment dispersant according to claim 1.   A pigment composition comprising a pigment and the cis-thiazineindigo pigment dispersant according to claim 2.   The pigment composition according to claim 3 or 4, wherein the pigment contains a diketopyrrolopyrrole red pigment, a quinacridone red pigment, a thiazine indigo red pigment, or an anthraquinone red pigment.   The pigment composition according to claim 5, wherein the pigment further contains a yellow pigment.   A coloring composition comprising the pigment composition according to any one of claims 3 to 6 and a pigment carrier.   A color filter comprising a filter segment formed from the colored composition according to claim 7.