JP2010163501A - METHOD FOR PRODUCING epsi-TYPE COPPER PHTHALOCYANINE PIGMENT, epsi-TYPE COPPER PHTHALOCYANINE PIGMENT PRODUCED BY THE METHOD, AND COLORED COMPOSITION USING THE SAME - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ε-type copper phthalocyanine pigment having low viscosity characteristics suitable for coating, and providing a film having high brightness, visibility, and high transmissivity when used for a color filter usable for a color liquid crystal display device and a solid image sensor. <P>SOLUTION: The ε-type copper phthalocyanine pigment is produced by carrying out a process for producing the ε-type copper phthalocyanine pigment in the presence of a sorbitan-based surfactant. The ε-type copper phthalocyanine pigment is produced well by adding the sorbitan-based surfactant in a step of carrying out wet milling in the presence of inorganic salts and an organic solvent. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a method for producing an ε-type copper phthalocyanine pigment. More specifically, the present invention has excellent dispersibility and stability over time, and excellent display quality when used for a color filter used in a color liquid crystal display device and a solid-state imaging device. It is related with the said pigment which can provide a color filter.

  A color filter is one in which two or more kinds of fine bands (stripes) of different hues are arranged in parallel or intersecting on the surface of a transparent substrate such as glass, or in which fine pixels are arranged in a constant vertical and horizontal arrangement. It has become. Since the pixel size is as fine as several tens to several hundreds of micrometers and is arranged in a predetermined arrangement for each hue, various methods have been proposed for manufacturing color filters. Since color filters require high transparency, they have been manufactured by a method of coloring using a dye, generally called a dyeing method. For example, a dyeable photosensitive material is applied to a substrate such as glass, followed by pattern exposure of one filter color, and then removing an unexposed portion in a development process, and removing the remaining pattern portion of the filter color. A color filter can be produced by sequentially repeating the operation of dyeing with a dye for all filter colors.

  A transparent electrode for driving the liquid crystal is generally formed on the color filter used in the color liquid crystal display device by vapor deposition or sputtering, and an alignment film for aligning the liquid crystal in a certain direction is further formed thereon. . In order to sufficiently obtain the performance of these transparent electrodes and alignment films, the formation thereof must generally be performed at a high temperature of 200 ° C. or higher, preferably 250 ° C. or higher.

As a color filter used in a color liquid crystal display device, an additive color mixture type of red (R), green (G), and blue (B) is generally used. The ε-type phthalocyanine pigment is used as a blue color forming pigment for these color filters.
As the liquid crystal display expands from a monitor application to a large color television application, a high contrast ratio and high brightness of a color filter for the liquid crystal display are required. As a result, in order to realize a high contrast ratio of the color filter, the pigment is further refined and sized so as to be higher than the level normally used in printing ink, gravure ink and colorant. However, it is impossible to achieve high brightness of the color filter only by making the pigment finer and sized.

  The ε-type copper phthalocyanine pigment has an excellent property that it has a reddish hue as compared with the α-type copper phthalocyanine pigment, and is highly vivid and has high coloring power. However, the ε-type copper phthalocyanine pigment obtained by a known and commonly used production method has a large primary particle diameter of the pigment when used in a blue pixel portion of a color filter. In either case, a low color filter blue pixel portion was obtained.

  Therefore, by making the primary particle size finer than before, when used for the color filter blue pixel part, although the effect of improving the sharpness, brightness, and contrast of the coating film is seen to some extent, the dispersibility and dispersion of the pigment are still When the pigment dispersion is prepared using the pigment because of its low stability, reaggregation of the pigment particles occurs, and it becomes unstable with high viscosity, resulting in insufficient fluidity and storage stability. And the color filter blue pixel part using this pigment dispersion has the fault that all of the sharpness of a coating film, brightness, contrast, and heat resistance are low.

Japanese Patent Laid-Open No. 2005-234209 JP 2001-288385 A JP 2002-80745 A JP 2002-121420 A

An ε-type copper phthalocyanine pigment having excellent dispersibility and stability over time, and a method for producing the same, can be obtained when used in a color filter used in a color liquid crystal display device and a solid-state image sensor. The purpose is to provide.
As a method for improving the dispersibility of the ε-type copper phthalocyanine pigment, for example, as disclosed in JP-A-2005-234209, a technique of surface treatment with a pigment derivative such as a sulfonic acid derivative of copper phthalocyanine is known. However, when the pigment derivative is added and the content of the ε-type copper phthalocyanine pigment is lowered, there is a problem that the sharpness and brightness are lowered.

In addition, as a blue pigment composition, Japanese Patent Laid-Open No. 2001-288385 and Japanese Patent Laid-Open No. 2002-80745 disclose that a copper phthalocyanine pigment and a carbazole dioxazine violet pigment are mixed and wet pulverized to obtain an ε-type copper phthalocyanine fine pigment. is there. However, carbazole dioxazine violet has poor dispersibility, and the fluidity and storage stability of the pigment dispersion using this ε-type copper phthalocyanine fine pigment are insufficient, and the vividness and lightness as a blue pigment are reduced. There was a drawback.
Further, JP-A-2002-121420 discloses that the brightness of the color filter is increased by obtaining a fine ε-type copper phthalocyanine pigment having a large specific surface area, but the dispersibility and storage stability are worse as the particle becomes finer. Become.

  It is an object of the present invention to provide an ε-type copper phthalocyanine pigment that has excellent dispersion stability and has high brightness, sharpness, and high transmittance when used as a blue pixel portion for a color filter.

That is, the present invention relates to a pigment composition characterized in that it is carried out in the presence of a sorbitan surfactant in the process of producing an ε-type copper phthalocyanine pigment.
The present invention also relates to a pigment composition characterized by adding a sorbitan surfactant in a wet pulverization of an ε-type copper phthalocyanine pigment in the presence of an inorganic salt and an organic solvent.
The present invention also relates to the above pigment composition in which 0.1 to 10 parts of a sorbitan surfactant is added per 100 parts by mass of ε-type copper phthalocyanine.

  Furthermore, the present invention relates to the ε-type copper phthalocyanine used as a blue pixel portion for a color filter.

The ε-type copper phthalocyanine pigment obtained in the present invention has a low viscosity characteristic suitable for coating when used in a color filter used in a color liquid crystal display device or a solid-state image sensor, and the obtained film has a high brightness. , Sharpness and high transmittance. By performing the epsilon-type copper phthalocyanine pigment in the presence of a sorbitan-based surfactant, a pigment composition that can be easily dispersed in a dispersion medium with a small amount of aggregation is obtained.
The color filter using the ε-type copper phthalocyanine pigment obtained in the present invention is different from the case where the surfactant is added to the pigment at the time of dispersion. And the surfactant is strongly adsorbed on the surface of the pigment, resulting in excellent dispersion stability.

Next, the present invention will be described in more detail with reference to embodiments of the invention.
The ε-type copper phthalocyanine pigment in the present invention is characterized by adding a sorbitan surfactant in the production process.
Although the addition amount of the sorbitan surfactant can be arbitrarily selected, it is preferably 0.1 to 10 parts, more preferably 0.5 to 5 parts, per 100 parts by mass of the ε-type copper phthalocyanine pigment. When the addition amount is small, the effect of improving the dispersion stability is small, and when the addition amount exceeds 10 parts, problems such as a decrease in coloring power and a deterioration in dispersibility occur.

  In the present invention, a sorbitan surfactant may be added in any step of the production process of ε-type copper phthalocyanine. For example, it can be added during crude pigment preparation and / or wet pulverization and / or after wet pulverization. The most preferable treatment method is a method in which sorbitan surfactant is added in the step of wet crushing ε-type copper phthalocyanine in the presence of an inorganic salt and an organic solvent. When added during wet pulverization, the surfactant is more strongly adsorbed on the primary particle surface of the pigment than when added after wet pulverization, and does not elute in the subsequent filtration and water washing steps. As a result, a dispersion liquid having weak pigment aggregation and excellent dispersion stability is obtained, and an ε-type copper phthalocyanine pigment having high brightness, sharpness and high transmittance can be obtained when used as a blue pixel portion for a color filter. .

As the sorbitan surfactant to be added in the present invention, sorbitan fatty acid ester and polyoxyethylene sorbitan fatty acid ester can be used.
Sorbitan fatty acid ester is a nonionic surfactant which is a mixture of partial esters of sorbitol and / or its anhydride and fatty acid.
The starting fatty acid of sorbitan fatty acid ester is a saturated or unsaturated linear fatty acid having 6 to 22 carbon atoms, particularly 8 to 18 carbon atoms, a mixed fatty acid containing these as a main component, or a branched chain chain having 8 to 36 carbon atoms. Fatty acids are preferred. Specifically, for example, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, coconut fatty acid, beef tallow fatty acid, 2-ethylhexanoic acid, isostearic acid and the like are particularly preferable. Lauric acid, palmitic acid, stearic acid, oleic acid.

The sorbitan fatty acid ester may be a mixture of monoester, diester, triester and tetraester in any proportion.
Polyoxyethylene sorbitan fatty acid ester is obtained by adding ethylene oxide to sorbitan fatty acid ester (monoester, triester).
Two or more sorbitan surfactants to be added in the present invention may be mixed and used as necessary. By mixing two or more kinds of sorbitan surfactants, the Griffin formula [this Griffin formula is expressed by HLB = (molecular weight of hydrophilic group portion / molecular weight of surfactant) × (100/5) It is. HLB (hereinafter abbreviated as HLB) can be adjusted.

Examples of the water-soluble inorganic salt that is a grinding agent used in the present invention include sodium chloride, potassium chloride, calcium chloride, barium chloride, sodium sulfate and the like.
The higher the amount of water-soluble inorganic salt used, the higher the pigment grinding effect, but it is preferably 1 to 50 times the weight of ε-type copper phthalocyani, and 1 to 20 times the weight in terms of productivity. More preferably. Furthermore, the water content in the water-soluble inorganic salt is preferably 1% or less.
The amount of the water-soluble organic solvent used is preferably 0.5 to 3 times the weight of the ε-type copper phthalocyanine, and more preferably 1 to 2 times the weight.

  The wetting agent used in the present invention is not particularly limited as long as it is brought into contact with ε-type copper phthalocyanine so that the ε-type copper phthalocyanine is moistened to increase the grinding effect and promote miniaturization. Organic solvents are preferred.

  Water-soluble organic solvents include methanol, ethanol, isopropanol, n-propanol, isobutanol, n-butanol, ethylene glycol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol, propylene Examples include goricol monomethyl ether acetate, acetone, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone and the like. These may be used as a mixture of two or more if necessary.

Moreover, it is preferable that the usage-amount of a water-soluble organic solvent is 0.1-10 times weight with respect to epsilon-type copper phthalocyanine, and it is more preferable that it is 1-4 times weight.
For wet grinding, if it is used in a small amount and adsorbs to ε-type copper phthalocyanine and does not run away in wastewater, benzene, toluene, xylene, ethylbenzene, chlorobenzene, nitrobenzene, aniline, pyridine, quinoline, tetrahydrofuran, dioxane, ethyl acetate, Isopropyl acetate, butyl acetate, hexane, heptane, octane, nonane, decane, undecane, dodecane, cyclohexane, methylcyclohesasan, halogenated hydrocarbon, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc. in combination with the above water-soluble organic solvent Also good. These may be used as a mixture of two or more if necessary.

Although there is no restriction | limiting in particular about the wet crushing apparatus used in this invention, It is using apparatus, such as a trimix (made by Inoue Seisakusho), a supermix (made by Shinei Machine), and a kneader (made by Inoue Seisakusho) with a high grinding effect. it can.
Although there is no restriction | limiting in particular about the operating conditions of the wet grinding apparatus in this invention, In order to advance grinding | pulverization by a grinding | pulverization media effectively, the following operating conditions are preferable when an apparatus is a kneader. That is, the rotation speed of the blade in the apparatus is preferably 10 to 200 rpm, and a relatively large biaxial rotation ratio is preferable because the grinding effect is large. The operation time is preferably 1 to 24 hours, and the internal temperature of the apparatus is preferably 50 to 150 ° C. The water-soluble inorganic salt that is a pulverizing medium preferably has a pulverized particle size of 5 to 50 μm, a sharp particle size distribution, and a spherical shape.

  In the present invention, a pigment derivative may be added for the purpose of promoting the refinement of the ε-type copper phthalocyanine pigment or for improving the dispersibility of the crystal stabilizer and the color filter. The pigment derivative to be added is not particularly limited, and examples thereof include copper phthalocyanine having a sulfonic acid group, copper phthalocyanine having a sulfonic acid amide group, and copper phthalocyanine having a phthalimidomethyl group. The pigment derivative may be added at any step during preparation of the crude pigment, pigmentation, or wet grinding.

  In the present invention, a resin and a higher fatty acid may be added as necessary during wet grinding.

  The resin that can be used is not particularly limited, but rosin, rosin derivative, rosin-modified maleic acid resin, rosin-modified phenolic resin, rubber derivative, protein derivative, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, polyvinyl acetate, Epoxy resin, acrylic resin, maleic resin, styrene resin, styrene-maleic acid copolymer resin, butyral resin, polyester resin, melamine resin, phenol resin, polyurethane resin, polyamide resin, polyimide resin, alkyd resin, rubber resin, cellulose And benzoguanamine resins and urea resins.

  Higher fatty acids are fatty acids that react with glycerin and react with glycerin, and are widely soluble in animal fats and vegetable oils. They are sparingly soluble in highly lipophilic water, such as palmitic acid and linoleic acid. , Stearic acid, linolenic acid, oleic acid and the like. As the higher fatty acid, a fatty acid having 10 or more carbon atoms is preferable, and an unsaturated higher fatty acid which is liquid at 20 ° C. to 30 ° C. is more preferable. In contrast, fatty acids with a small number of carbons include acetic acid, valeric acid, and lactic acid, which are free acid and hydrophilic. Higher fatty acids with strong lipophilicity are suitable as the fatty acid that wets the pigment to increase the grinding effect and promotes refinement. In addition, water-soluble inorganic salts and water-soluble organic solvents used in wet grinding are separated from the pigment by washing with water, but hydrophilic fatty acids with a small number of carbons are dissolved in water, resulting in BOD and COD. This is not preferable because it causes an increase. Two or more types of higher fatty acids may be used as needed.

  The production method of the ε-type phthalocyanine pigment used in the present invention is not particularly limited. For example, as shown in JP-A-57-141453, it is directly synthesized from phthalimide. In addition, as disclosed in JP-A-48-76925, first, α-type phthalocyanine pigment is produced from crude phthalocyanine by an acid pasting method, and then the α-type phthalocyanine pigment and crystal stabilizer are milled. To obtain a crystal transition. Whether it is an ε-type phthalocyanine pigment can be qualitatively and quantitatively determined by X-ray diffraction. The ε-type copper phthalocyanine pigment has a Bragg angle 2 θ (allowable range ± 0.2 degrees) according to an X-ray diffraction diagram (Cu K α ray) = 9. It has the strongest diffraction peak at 2 degrees. The phthalocyanines used in the present invention need not all be ε-type phthalocyanine pigments, and may contain α-type or β-type phthalocyanine.

  The ε-type copper phthalocyanine pigment of the present invention can be used in a pigment carrier to provide offset printing ink, gravure printing ink, waterless offset printing ink, silk screen printing ink, solvent development type or alkali development type color resist. It can be set as a coloring composition.

  The colored composition obtained by uniformly dispersing the ε-type copper phthalocyanine pigment of the present invention in a pigment carrier exhibits stable viscosity characteristics, and by using the colored composition, high brightness, sharpness, and high transmittance can be obtained. The color filter which has can be manufactured.

The pigment carrier is composed of a resin, its precursor, or a mixture thereof. Resins include thermosetting resins, thermoplastic resins, and active energy ray curable resins, and precursors of resins include monomers and oligomers that form a coating film similar to the resin by being cured by irradiation with active energy rays. These can be used alone or in combination of two or more. The pigment carrier can be used in an amount of preferably 50 to 700 parts by weight, more preferably 100 to 400 parts by weight with respect to 100 parts by weight of the ε-type copper phthalocyanine pigment.
In the case of producing a color filter using a colored composition, the resin is preferably a transparent resin having a transmittance of 80% or more, preferably 95% or more in the entire wavelength region of 400 to 700 nm in the visible light region. . In addition, since a high-temperature heating process is performed in a later process in manufacturing the color filter, it is necessary to use a resin having good heat resistance.

  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 resins, polyamide resins, rubber resins, cyclized rubber resins, celluloses, polyethylene (HDPE, LDPE), 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.

  Active energy ray curable resins include polymers having reactive substituents such as hydroxyl groups, carboxyl groups, amino groups, (meth) acrylic compounds, cinnamic acid via isocyanate groups, aldehyde groups, epoxy groups, etc. A resin having a photocrosslinkable group introduced therein is used. Further, a linear polymer containing an acid anhydride such as a styrene-maleic anhydride copolymer or an α-olefin-maleic anhydride copolymer is converted into a (meth) acrylic compound having a hydroxyl group such as hydroxyalkyl (meth) acrylate. Half-esterified polymers can also be used.

  Resin precursor monomers and oligomers include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, cyclohexyl (meth) acrylate, polyethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, Various acrylic and methacrylic acid esters such as dipentaerythritol hexa (meth) acrylate, tricyclodecanyl (meth) acrylate, hexa (meth) acrylate of caprolactone adduct of dipentaerythritol hexa (meth) acrylate, acrylic acid, Methacrylic acid, (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, styrene, vinyl acetate, acrylonitrile, melamine (meth) acrylate, epoxy (Meth) acrylate prepolymer, and the like.

  When the composition is cured by ultraviolet irradiation, a photopolymerization initiator or the like is added to the colored composition. Examples of the photopolymerization initiator include 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, diethoxyacetophenone, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- Hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane Acetophenone photopolymerization initiators such as -1-one, benzoin photopolymerization initiators such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzyldimethyl ketal, benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4 Benzophenone photopolymerization initiators such as phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2 Thioxanthone photopolymerization initiators such as 2,4-diisopropylthioxanthone, 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis (trichloromethyl) -s-triazine, 2- (p -Methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (p-tolyl) -4,6-bis (trichloromethyl) -s-triazine, 2-piperonyl-4,6-bis (Trichloromethyl) -s-triazine, 2,4-bis (tri (Loromethyl) -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, etc. A polymerization initiator, a borate photopolymerization initiator, a carbazole photopolymerization initiator, an imidazole photopolymerization initiator, or the like is used. A photoinitiator can be used in the quantity of 5-150 weight part with respect to 100 weight part of epsilon-type copper phthalocyanine pigments.

  The above photopolymerization initiators are used alone or in combination of two or more. As sensitizers, α-acyloxy esters, acylphosphine oxides, methylphenylglyoxylate, benzyl, 9,10-phenance are used. Such as lenquinone, camphorquinone, ethylanthraquinone, 4,4′-diethylisophthalophenone, 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone, 4,4′-diethylaminobenzophenone, etc. A compound can also be used in combination. The sensitizer can be used in an amount of 0.1 to 150 parts by weight with respect to 100 parts by weight of the photopolymerization initiator.

  In the coloring composition, a solvent can be used in order to sufficiently disperse the pigment in the pigment carrier and uniformly apply it to the substrate. Examples of the solvent include cyclohexanone, ethyl cellosolve acetate, butyl cellosolve acetate, 1-methoxy-2-propyl acetate, diethylene glycol dimethyl ether, ethylbenzene, ethylene glycol diethyl ether, xylene, ethyl cellosolve, methyl-n amyl ketone, propylene glycol monomethyl ether toluene, methyl ethyl ketone. , Ethyl acetate, methanol, ethanol, isopropyl alcohol, butanol, isobutyl ketone, petroleum solvent and the like, and these are used alone or in combination. The solvent can be used in an amount of 500 to 4000 parts by weight with respect to 100 parts by weight of the ε-type copper phthalocyanine pigment.

  Various dispersing means such as a three-roll mill, a two-roll mill, a sand mill, and a kneader can be used for dispersing the ε-type copper phthalocyanine pigment of the present invention in the pigment carrier. Moreover, in order to make these dispersion | distribution favorable, dispersion | distribution adjuvants, such as various surfactant and a pigment derivative, can be added suitably. The dispersion aid is excellent in dispersing the pigment and has a great effect of preventing reaggregation of the pigment after dispersion. These coloring compositions such as printing ink and coloring resist agent are coarse particles of 5 μm or more, preferably coarse particles of 1 μm or more, more preferably 0.5 μm by means of centrifugation, sintered filter, membrane filter or the like. It is preferable to remove the coarse particles and the mixed dust.

  Since the coloring composition of the present invention adjusts to a desired chromaticity, other blue pigments, violet pigments, red violet pigments, or the like can be used in combination as necessary. These pigments are preferably added within a range that does not impair the color characteristics. In addition, these pigments may be surface-treated pigments in which the surface of the pigment particles is coated with a surface treatment agent such as a known and commonly used pigment derivative, dispersant, surfactant, and resin, if necessary. Specifically, the violet pigment is a dioxazine pigment, the red violet pigment is a quinacridone pigment, the blue pigment is a selenium pigment (also called an anthraquinone pigment), a stron pigment, an indigo pigment, phthalocyanine. A pigment or the like can be used. Among these, it is preferable to use a dioxazine pigment in consideration of the total aspect of hue, light resistance, heat resistance, and price. Examples of the dioxazine pigment include C.I. I. Pig gent Vio olet 2 3, 3 7, and the like.

  When the blue pigment, purple pigment, or red purple pigment that can be used in combination with the present invention is used in a color filter, the wavelength (Tmax) at which the transmittance of the spectral transmission spectrum is maximized picks up the desired emission line of the backlight source. Can be used for

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example and a comparative example, this invention is not limited by this. Hereinafter, “parts” and “%” represent “parts by weight” and “% by weight”.

  ε-type copper phthalocyanine pigment (LIONOL BLUE E manufactured by Toyo Ink Manufacturing Co., Ltd.), 600 parts of sodium chloride, and 100 parts of diethylene glycol in a laboratory 3L kneader manufactured by Inoue Seisakusho, keeping the temperature of the contents at 70-80 degrees for 6 hours Wet crushed. At that time, 1.6 parts of “Leodol SP-O10V” (Sorbitan fatty acid ester activator, HL 4.3, manufactured by Kao Corporation) was added from the beginning. After taking out the contents, sodium chloride and diethylene glycol were dissolved in 3000 parts of water by stirring at 70 ° C. for 60 minutes. The slurry was filtered and washed with water to purify impurities, and then heat treated at 90 ° C. for 24 hours with a dryer to obtain a dry pigment. An ε-type phthalocyanine pigment treated with a sorbitan active agent was obtained by pulverization with a small pulverizer for laboratories.

(Preparation of acrylic resin solution)
The reaction vessel was charged with 800 parts by weight of cyclohexanone, heated to 100 ° C. while injecting nitrogen gas into the vessel, and a mixture of the following monomer and thermal polymerization initiator was added dropwise over 1 hour at the same temperature to carry out the polymerization reaction. .
Styrene 60.0 parts by weight Methacrylic acid 60.0 parts by weight Methyl methacrylate 65.0 parts by weight Butyl methacrylate 65.0 parts by weight Azobisisobutyronitrile 10.0 parts by weight

  After the dropwise addition, the mixture was further reacted at 100 ° C. for 3 hours, then 2.0 parts by weight of azobisisobutyronitrile dissolved in 50 parts by weight of cyclohexanone was added, and the reaction was further continued at 100 ° C. for 1 hour. An acrylic resin solution having an average molecular weight of about 40,000 was obtained. After cooling to room temperature, about 2 g of the resin solution was sampled, heated and dried at 180 ° C. for 20 minutes to measure the nonvolatile content, and cyclohexanone was added to the previously synthesized resin solution so that the nonvolatile content was 20%. An acrylic resin solution was prepared.

(Preparation of pigment dispersion) In a 140 ml mayonnaise bottle, 150 g of steel beads having a diameter of 2 mm, 11.5 g of the ε-type phthalocyanine pigment prepared in Example 1, a dispersion aid (N, N′-diethylaminopropylaminoacetamidomethyl copper phthalocyanine) ) 0.5 g, 40.0 g of the above acrylic resin solution and 30.0 g of cyclohexanone were added and dispersed for 3 hours with a paint conditioner. Next, 73.2 g of the acrylic resin solution and 13.2 g of cyclohexanone were added to 60 g of the dispersion from which the steel beads were separated, and the mixture was stirred and mixed uniformly to prepare a dispersion of ε-type phthalocyanine pigment.

An ε-type phthalocyanine pigment was obtained in accordance with Example 1 except that the amount of “Rheodor SP-O10V” (Kao Corporation sorbitan fatty acid ester activator, HLB.1.8) was changed to 4 parts. It was. Using the obtained ε-type phthalocyanine pigment, a pigment dispersion was prepared in the same manner as in Example 1.

Instead of “Leodol SP-O10V” (Kao Corporation sorbitan fatty acid ester activator, HLB.1.8), “Leodol TW-O106V” (Kao Corporation sorbitan fatty acid ester activator, HL. An ε-type phthalocyanine pigment was obtained according to Example 1 except that B.10.0) was added. Using the obtained ε-type phthalocyanine pigment, a pigment dispersion was prepared in the same manner as in Example 1.

Instead of “Leodol SP-O10V” (Kao Corporation sorbitan fatty acid ester activator, HLB.1.8), “Leodol SP-O30V” (Kao Corporation sorbitan fatty acid ester activator, HL. An ε-type phthalocyanine pigment was obtained according to Example 1 except that B.1.8) was added. Using the obtained ε-type phthalocyanine pigment, a pigment dispersion was prepared in the same manner as in Example 1.

Instead of adding “Leodol SP-O10V” (Sorbitan fatty acid ester activator manufactured by Kao Corporation, HLB.1.8) from the initial stage during wet grinding, except that it is added 5 hours after the start of wet grinding. According to Example 1, an ε-type phthalocyanine pigment was obtained. Using the obtained ε-type phthalocyanine pigment, a pigment dispersion was prepared in the same manner as in Example 1.

Instead of “Leodol SP-O10V” (Kao Corporation sorbitan fatty acid ester activator, HLB.1.8), “Leodol SP-O10V” (Kao Corporation sorbitan fatty acid ester activator, HL. B.1.8) 0.8 part and "Rheodor TW-O106V" (Kao Co., Ltd. polyoxyethylene sorbitan fatty acid ester activator, HLB 10.0) mixed with 0.8 part Except for the above, an ε-type phthalocyanine pigment was obtained according to Example 1. Using the obtained ε-type phthalocyanine pigment, a pigment dispersion was prepared in the same manner as in Example 1.

Instead of adding “Leodol SP-O10V” (Kao Corporation sorbitan fatty acid ester activator, HLB.1.8) during wet grinding, except adding to the pigment aqueous dispersion after wet grinding. According to Example 1, an ε-type phthalocyanine pigment was obtained. Using the obtained ε-type phthalocyanine pigment, a pigment dispersion was prepared in the same manner as in Example 1.

[Comparative Example 1]
An ε-type phthalocyanine pigment was obtained in accordance with Example 1 except that “Leodol SP-O10V” (a sorbitan fatty acid ester activator manufactured by Kao Corporation, HLB.1.8) was not added during wet grinding. Using the obtained ε-type phthalocyanine pigment, a pigment dispersion was prepared in the same manner as in Example 1.

[Comparative Example 2]
An ε-type phthalocyanine pigment was obtained in accordance with Example 1 except that “Leodol SP-O10V” (a sorbitan fatty acid ester activator manufactured by Kao Corporation, HLB.1.8) was not added during wet grinding. Other than adding 0.23 part of “Leodol SP-O10V” (Sorbitan fatty acid ester activator manufactured by Kao Corporation, HLB.1.8) at the time of preparing the pigment dispersion using the obtained ε-type phthalocyanine pigment. Obtained a pigment dispersion in the same manner as in Example 1.

[Comparative Example 3]
Instead of “Leodol SP-O10V” (Kao Corporation sorbitan fatty acid ester activator, HLB.1.8), “Emulgen 105” (Kao Corporation polyoxyethylene lauryl ether activator, HL. B.9.7, a nonionic surfactant that is not a sorbitan surfactant, and an ethylene oxide added in the same manner as the polyoxyethylene sorbitan fatty acid ester surfactant). A phthalocyanine pigment was obtained. Using the obtained ε-type phthalocyanine pigment, a pigment dispersion was prepared in the same manner as in Example 1.
(Evaluation of color filter characteristics of pigments obtained in Examples and Comparative Examples)
The chromaticity and lightness of the pigments obtained in Examples and Comparative Examples were measured. In these evaluations, a colored resist material was prepared, the colored resist material was applied to a glass substrate using a spin coater, and the chromaticity and brightness of the coated substrate after exposure and heating were measured. The evaluation method will be described in detail below.
(Preparation of Colored Resist Material) A mixture having the following composition was stirred and mixed uniformly, and then filtered through a 1 μm filter to prepare an alkali developing type colored resist material.
ε-type phthalocyanine pigment dispersion 4.5 parts

(Examples 1-7 and Comparative Examples 1-3)
Acrylic resin solution 24.0 parts monomer (“NK ester ATMPT” manufactured by Shin-Nakamura Chemical Co., Ltd.) 5.4 parts photoinitiator (“Irgacure 907” manufactured by Ciba Geigy Co., Ltd.) 0.3 parts sensitizer (manufactured by Hodogaya Chemical Co., Ltd.) "EAB-F") 0.2 part cyclohexanone 65.6 parts

  The colored resist materials prepared using the pigments obtained in Examples 1 to 7 and Comparative Examples 1 to 3 were placed on a glass substrate of 100 mm × 100 mm and 1.1 mm thickness using a spin coater at 500 rpm, 1000 rpm, and 2000 rpm. The three coating substrates having different film thicknesses were obtained. Next, after drying at 70 ° C. for 20 minutes, ultraviolet exposure was performed with an integrated light amount of 150 mJ using an ultrahigh pressure mercury lamp. The coated substrate was heated at 230 ° C. for 1 hour and then allowed to cool to produce a colored film. Then, the spectrum of the obtained colored film was measured with a spectrophotometer (“U-3500” manufactured by Hitachi, Ltd.), and each chromaticity (Y, x, y) with a C light source was calculated, and y = 0. Each Y at 12 was further calculated. The results are shown in Table 1.

Contrast is measured using a contrast measuring device (“CT-1” manufactured by Osaka Co., Ltd.), and the color filter blue pixel part is placed between two polarizing plates, with a light source on one side and a light source on the other side. C C D camera is installed, and chromaticity y = 0. The brightness was measured at a position of 12. It was calculated from the ratio of luminance (transmitted light intensity) between when the polarization axis was parallel and when it was vertical. Table 1 shows the contrast ratio when the contrast of Comparative Example 1 is used as a standard.
The viscosity of the obtained colored resist material was measured with an EL type viscometer (TV-20 unit manufactured by Toki Sangyo Co., Ltd., mPa · s). Table 1 shows the values at 25 ° C. and 100 rpm.

As is clear from Table 1, in the blue pixel portions of the color filters of Examples 1 to 7, a pigment dispersion is weak and a dispersion having excellent dispersion stability is formed. The blue pixel portion obtained therefrom has a contrast and brightness of the coating film. high. On the other hand, in the color filter blue pixel portion of Comparative Examples 1 to 3, since the dispersion of the pigment is strong and the dispersion stability is poor, the blue pixel portion obtained from the dispersion has low contrast and brightness. Yes.

Claims (6)

  A method for producing an ε-type copper phthalocyanine pigment, which is performed in the presence of a sorbitan surfactant.   The method for producing an ε-type copper phthalocyanine pigment according to claim 1, wherein a sorbitan surfactant is added in the wet pulverization step in the presence of an inorganic salt and an organic solvent. The method for producing an ε-type copper phthalocyanine pigment according to claim 1 or 2, wherein 0.1 to 10 parts of a sorbitan surfactant is added per 100 parts by mass of ε-type copper phthalocyanine. A pigment composition comprising ε-type copper phthalocyanine produced by the method according to claim 1. A coloring composition comprising the ε-type copper phthalocyanine pigment composition according to claim 4 and a pigment carrier. A color filter comprising the ε-type copper phthalocyanine pigment composition according to claim 4 in a blue pixel portion.