JP6536645B2 - Surface-treated organic pigment for color filter, method for producing the same, and color filter - Google Patents

Description

  The present invention relates to a surface-treated organic pigment for color filter, a method for producing the same, and a color filter.

  When dispersing the organic pigment in a medium that requires coloring, it is possible to more easily disperse the organic pigment or to increase the stability in the medium after dispersion, it is preferable to use an organic pigment comprising a surfactant or an organic pigment derivative. Surface treatment is often performed. This surface treatment can improve the dispersibility and dispersion stability of the organic pigment which has not been subjected to any surface treatment.

  When the medium requiring dispersion is a synthetic resin, the synthetic resin is also often used in this surface treatment. Specifically, a method of solvent salt milling an organic pigment in the presence of an acrylic resin nonvolatile matter is known.

  The surface treatment of organic pigments with synthetic resin has been studied according to the categories of polymers, such as (meth) acrylic resin, epoxy resin, polyester resin, polyurethane resin, etc., but specifically what category it is Systematic investigations as to whether the polymer of the present invention is highly effective in improving the dispersibility and dispersion stability, and what structure of the polymer within the polymer of the same category is selectively the most effective. It is not the case that there are many unknown points.

  By the way, organic pigments used for high-performance applications such as inkjet inks and color resists for color filters are required to have high-resolution printing compared to general-purpose organic pigments used for coloring paints and thermoplastic plastic molded articles Therefore, finer organic pigments are required.

  However, since fine organic pigments are more likely to aggregate than general purpose organic pigments, it is not always necessary to use any synthetic resin for surface treatment by the method of surface treatment of organic pigments used in general purpose applications. However, the improvement effect as expected is not necessarily obtained, but it is the fact that the synthetic resin of the optimal structure is selected in the optimal category by trial and error.

  Specifically, for example, as a method for surface treatment of an organic pigment used for preparation of a color resist for color filter, a method of solvent salt milling an organic pigment in the presence of (meth) acrylic resin nonvolatile matter (Patent Document 1) There is known a method of pressure heating an organic pigment in a liquid medium in the presence of a polyurethane resin (Patent Document 2).

JP-A-8-179111 WO 10/061830

  However, the color saturation of the colored material obtained from the organic pigment surface-treated by the above-described conventional manufacturing method is still insufficient, and the color hue of the colored material changes significantly when it is subjected to a heat history over a long period of time. The fact is that the heat resistance is also inferior.

  Then, when the present inventors earnestly examined the surface treatment effect of organic pigment using various synthetic resins in order to solve the above-mentioned subject, the number of carbon atoms of a side chain differs, and two or more kinds of (meta) acrylic acid esters differ. The surface treatment with the copolymer of the present invention provides a colored product in which the above-mentioned drawbacks are eliminated, and in particular, a color filter used for a liquid crystal display which is exposed to high temperatures for a long time in manufacturing processes or conditions of use. In the present invention, it has been found that the color filter can be a liquid crystal display excellent in heat resistance of luminance, and the present invention is completed.

That is, according to the present invention, 0.1 to 15 parts of (B) a copolymer having two or more (meth) acrylic acid esters each having a different number of carbon atoms in the side chain, per 100 parts of organic pigment (A) in mass conversion. Provided is a surface-treated organic pigment for color filter characterized by containing.
In the liquid medium, the organic pigment (A) is heated under pressure in the presence of a copolymer of two or more (meth) acrylates having different numbers of carbon atoms in side chains in the liquid medium (B) nonvolatile matter Or a copolymer of two or more (meth) acrylates having different numbers of carbon atoms in side chains (B) Surface-treated organic pigment for color filter which solvent salt-mills organic pigment (A) in the presence of nonvolatile matter Provide a manufacturing method.
Furthermore, according to the present invention, a color filter comprising any one of the surface-treated organic pigments described above in a pixel portion.

Since the surface-treated organic pigment of the present invention contains the organic pigment (A) and the specific copolymer (B) at a predetermined ratio, the color change of the colored product is caused even if the heat history is received for a long time It has an extremely remarkable technical effect that a small colored product having excellent heat resistance can be obtained.
Further, the method for producing a surface-treated organic pigment of the present invention has an extremely remarkable technical effect that the above-mentioned surface-treated organic pigment can be easily obtained.
Furthermore, since the color filter of the present invention contains the above-described surface-treated organic pigment or the surface-treated organic pigment obtained by the above-described production method in the pixel portion, liquid crystal display excellent in heat resistance of luminance is possible. It produces exceptional technical effects.

  The surface-treated organic pigment of the present invention is a copolymer of two or more (meth) acrylates having different numbers of carbon atoms in side chains per 100 parts of the organic pigment (A) in terms of mass (B) nonvolatile matter 0.1 .About.15 parts.

  Examples of the organic pigment (A) include all known and commonly used pigments such as phthalocyanine pigments, quinacridone pigments, azo pigments, dioxazine pigments, anthraquinone pigments, diketopyrrolopyrrole pigments, organic metal complex pigments and the like.

  The organic pigment (A) in the present invention may be of any particle size, but the coloring agent is a clear powder when the average particle size of primary particles is 100 nm or less in the dry powder. Because it is easy to obtain On the other hand, since the heat resistance is generally lower as the particle size of the organic pigment (A) is smaller in many cases, it is necessary to improve the heat resistance by some means without impairing the sharpness.

  In the present invention, the average particle size of primary particles is measured as follows. First, the particles in the field of view are photographed with a transmission electron microscope or a scanning electron microscope. Then, the longest length (maximum length) of the inner diameter of each particle is determined for 50 primary particles constituting an aggregate on a two-dimensional image. The average value of the maximum length of individual particles is taken as the average particle size of primary particles.

  In addition, copolymers of two or more (meth) acrylic esters having different numbers of carbon atoms in side chains (B

Any of known and commonly used ones can be used as the (Meth) acrylic acid ester is a compound containing an ester bond such as that formed from (meth) acrylic acid and various other alcohols, and a carbon atom chain at the end of the ester bond COO derived from the above alcohol Say what contains. Typically, those in which the carbon chain is an alkyl group are referred to as (meth) acrylic acid alkyl esters. In the case of (meth) acrylic acid alkyl ester, the side chain means an alkyl group. In the industry, not only (meth) acrylic acid alkyl esters but also compounds in which the above carbon chain is other than an alkyl group are well known, so in the present invention, not only (meth) acrylic acid alkyl esters but also carbon chains , And compounds other than alkyl groups are referred to as (meth) acrylic acid esters.

  As such (meth) acrylic acid ester, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) which is (meth) acrylic acid alkyl ester Acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, dodecyl (meth) acrylate [lauryl (meth) acrylate (Meth) acrylic acid alkyl ester having an alkyl group such as acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate), etc .; cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, adamantyl Meth) acrylate, containing an alicyclic group such as dicyclopentanyl (meth) acrylate (meth) acrylic acid ester;

Methoxy triethylene glycol (meth) acrylate, methoxy polyethylene glycol # 400 (meth) acrylate, methoxy dipropylene glycol (meth) acrylate, methoxy tripropylene glycol (meth) acrylate, methoxy polypropylene glycol (meth) acrylate, ethyl carbitol (meth ) Acrylate, 2-ethylhexyl carbitol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, p-nonyl phenoxyethyl (meth) acrylate, p-nonyl phenoxy polyethylene (Meth) acrylic acid esters containing an ether group such as glycol (meth) acrylate; (Meth) containing an aromatic ring acrylate (meth) acrylic acid ester;
And so on.

  In the present invention, a copolymer (B) of two or more kinds of (meth) acrylic acid esters having different numbers of carbon atoms in side chains is a carbon atom of a side chain among various (meth) acrylic acid esters as described above. It means a polymer obtained by selecting and copolymerizing two or more kinds selected from different numbers.

  As the copolymer (B), although the one having the highest possible glass transition temperature (Tg) is excellent in the heat resistance of itself, when used in combination with the organic pigment (A), the heat resistance excellent due to the interaction is obtained. Copolymers having a Tg of 0 to 150 ° C. are more preferred in terms of their ability to be exhibited.

  As the copolymer (B), one having any molecular weight can be used, but specifically, the copolymer having a weight average molecular weight of 5,000 to 100,000 has an affinity for the organic pigment (A) The heat resistance is preferably high because the heat resistance improvement effect is also large.

  The copolymer (B) can be synthesized by various conventionally known reaction methods such as bulk polymerization, solution polymerization, suspension polymerization and emulsion polymerization. At this time, known and commonly used polymerization initiators, surfactants and antifoaming agents can be used in combination.

  The copolymer (B) contains, as essential monomers, two or more kinds of (meth) acrylates having different numbers of carbon atoms in side chains as described above, in combination with other comonomers copolymerizable therewith. It may be copolymerized.

  Such comonomers include, for example, vinyl esters such as vinyl acetate, vinyl propionate, and vinyl tertiary carboxylate; heterocyclic vinyl compounds such as vinyl pyrrolidone; vinyl chloride, vinylidene chloride, vinylidene fluoride, etc. Cyano-containing monomers such as halogenated olefins, acrylonitrile and methacrylonitrile; vinyl ethers such as ethyl vinyl ether and isobutyl vinyl ether; vinyl ketones such as methyl vinyl ketone; α-olefins such as ethylene and propylene; butadiene, Dienes such as isoprene; styrene-based monomers such as styrene, vinyl toluene, α-methylstyrene, dimethylstyrene, tert-butylstyrene, chlorostyrene and the like.

  According to the present inventors, the copolymer (B) is a copolymer containing not only side chains having different numbers of carbon atoms but also epoxy groups derived from two or more (meth) acrylic acid esters. It has been found that the color change is less likely to change even under heat history and the heat resistance is better than a copolymer containing only side chains having different numbers of carbon atoms.

  The method for introducing the above-mentioned epoxy group into the copolymer is not particularly limited, and even if the radically polymerizable monomer containing an epoxy group is polymerized as an essential component, the copolymer synthesized earlier is used later. Although epoxy group modification may be carried out, since introduction is easy, a monomer containing two or more kinds of (meth) acrylic acid esters having different number of carbon atoms in side chains and an epoxy group is polymerized as an essential component Is preferred.

  Examples of the monomer having an epoxy group include epoxy group-containing monomers such as glycidyl (meth) acrylate, allyl glycidyl ether, and 4-hydroxybutyl (meth) acrylate glycidyl ether.

  As the copolymer (B), preferred is a copolymer obtained by polymerizing a monomer containing two or more kinds of (meth) acrylic acid esters different in the number of carbon atoms in the side chain described above and an epoxy group as an essential component The copolymer having 3 to 35% by mass of the monomer having an epoxy group is 100% based on the mass conversion of all the monomers constituting the copolymer (B). Higher heat resistance can be obtained compared to a copolymer consisting of only two or more (meth) acrylates having different numbers of carbon atoms in side chains, and dispersibility in a medium to be colored which requires coloring is also possible. It is preferable because it becomes good.

In a copolymer in which the monomer having an epoxy group is 3 to 35% by mass of all the monomers, the greater the amount occupied by the monomer having an epoxy group, the color saturation upon receiving heat history and the like The change in chromaticity tends to be small.
The epoxy group in the copolymer (B) may be partially or entirely reacted with a nucleophile to form a ring-opened functional group. For example, even when a copolymer (B) in which all of the epoxy groups in the copolymer have reacted with hydrochloric acid to form α-chlorohydrin groups is used as the copolymer containing the original epoxy group. It has the same heat resistance improvement effect as it did.

  In the surface-treated organic pigment of the present invention, the copolymer (B) having a nonvolatile content of two or more (meth) acrylates having different numbers of carbon atoms in side chains per 100 parts of the organic pigment (A) in mass conversion is 0. The content of the copolymer (B) is preferably in the range of 0.5 to 12 parts, particularly 1 to 10 parts per 100 parts of the organic pigment (A), although it may be contained to be 1 to 15 parts. In particular, it is preferable because it can be a surface-treated organic pigment having the best balance of technical effects in the present invention, other technical effects such as dispersibility in a medium to be colored and dispersion stability, and economy.

  Such surface-treated organic pigment of the present invention can be prepared by mixing the organic pigment (A) and the copolymer (B) by any means. As a simple preparation method, for example, a method of mixing the organic pigment (B) and the copolymer (B) non volatile matter, mixing the organic pigment (A) in a liquid medium solution of the copolymer (B) and stirring And filter drying.

  However, the present inventors can expect a stronger interaction between the organic pigment (A) and the copolymer (B) than the simple preparation method described above, specifically, in the liquid medium, The organic pigment (A) is heated under pressure in the presence of a copolymer of two or more (meth) acrylates having different numbers of carbon atoms in the chain (B), or the number of carbon atoms in the side chain is different (Meth) Acrylate Ester Copolymer of Two or More Kinds (B) The Surface-Treated Organic Pigment Prepared by Solvent Salt Milling of the Organic Pigment (A) in the Presence of Nonvolatile Content is the Simple Method Described Above It has been found for the first time that a greater effect of improving the heat resistance is exerted as compared to the surface-treated organic pigment prepared in the above. Hereinafter, the former preparation method is referred to as a pressure heating method, and the latter preparation method is referred to as a solvent salt milling method.

  The above-mentioned two methods for producing a surface-treated organic pigment of the present invention are, for example, C.I. I. Pigment blue 15: 6 (ε-type copper phthalocyanine pigment), C.I. I. Pigment green 36 (halogenated copper phthalocyanine pigment) and C.I. I. This is a particularly excellent method of producing surface-treated organic pigments containing phthalocyanine pigments such as CI Pigment Green 58 (halogenated zinc phthalocyanine pigments).

  First, the pressure heating method will be described. According to the pressure heating method, for example, heating is performed by mixing and stirring an organic pigment (A) and a solution or dispersion in which a copolymer (B) is dissolved or dispersed in a liquid medium. The copolymer (B) can coat the surface of the organic pigment (A) more uniformly and reliably as compared with the case where no. In addition, by applying pressure heating, not only the coating of the copolymer (B) on the surface of the organic pigment (A) particles in the case of simple heating but also voids such as the pores of the organic pigment (A) particles The penetration of the copolymer (B) into the part can be promoted, and the effect of the coating is enhanced.

  At this time, when using a liquid medium containing only water or a water-soluble organic solvent (referred to as an aqueous medium) as the liquid medium, the mixing heating is carried out using only the organic solvent as the liquid medium. Compared with this, it is preferable because the change in the crystal shape of the organic pigment (A) itself is small and the change in hue is small.

  Examples of the above-mentioned water-soluble organic solvent include propylene glycol monomethyl ether acetate, ethyl alcohol, isopropyl alcohol, isobutyl alcohol and the like.

  It is preferable that the aqueous medium used for pressure heating be a large excess with respect to the organic pigment (A), and that 15 to 100 parts per mass of the organic pigment (A) is obtained by pressure heating. The amount of the copolymer (B) charged in the coating of the organic pigment (A) to reduce the outflow of the copolymer (B) in the filtration step described later. It is more preferable to shorten the same process time itself.

  When a surface-treated organic pigment is prepared from the organic pigment (A) and the copolymer (B) by a pressure heating method, the surface-treated organic pigment finally obtained is the organic pigment (A) 100 in mass conversion. Both parts are charged so that the amount of the copolymer (B) is 0.5 to 12 parts per part, but the interaction including the adsorption between the organic pigment (A) and the copolymer (B) is strong. The copolymer (B) non volatile matter which is charged does not flow out, and at least 70% of the non volatile matter in terms of mass remains in the organic pigment (A).

  Heating of the organic pigment (A) and the copolymer (B) may be carried out in a range of 30 minutes to 5 hours in a closed system under stirring at a temperature of 100 to 150 ° C. after mixing the two. it can. Thus, by heating in a closed system, a pressurized state is formed, and as described above, the copolymer (B) penetrates into the voids of the pigment particles, and only the particle surface is covered. Compared to, a better effect is expressed.

  Next, the solvent salt milling method will be described. According to the solvent salt milling method, for example, an organic pigment (A) and a copolymer (B) are kneaded by applying a mechanical stress with a water-soluble inorganic salt and a hydrophilic organic solvent, and the organic pigment (A) The copolymer (B) can be uniformly and reliably coated on the surface of the organic pigment (A) while making the particle diameter of the particle smaller and making the particle shape into a substantially cubic shape.

  Specifically, in this solvent salt milling, an organic pigment, a water-soluble inorganic salt, and a hydrophilic organic solvent which does not dissolve it are placed in a kneader, and kneading and grinding are performed therein. In the above kneading, if conversion of the crystal form of the raw material is not intended, a commercially available ε-type copper phthalocyanine pigment can be used as the raw material for kneading as the organic pigment (A). On the other hand, when conversion of crystal form and the like are intended, a crude organic pigment of a crystal form different from that after kneading can be used as a raw material for kneading as the organic pigment (A). Specifically, the ε-type copper phthalocyanine pigment can also be obtained by the above-mentioned kneading using a crude α-type copper phthalocyanine pigment as a raw material.

  In the case of preparing a surface-treated organic pigment from the organic pigment (A) and the copolymer (B) by the solvent salt milling method, the surface-treated organic pigment finally obtained is a co-compound per 100 parts of the organic pigment (A) Both are charged so as to be 0.5 to 12 parts of the polymer (B), but the pressure is high because the interaction including the adsorption between the organic pigment (A) and the copolymer (B) is strong. Similar to the heating method, the copolymer (B) non-volatile component charged hardly leaves at least 70% of the non-volatile component in terms of mass remains in the organic pigment (A).

  As the water-soluble inorganic salt, for example, inorganic salts such as sodium chloride, potassium chloride, sodium sulfate and the like are preferably used. Further, it is more preferable to use an inorganic salt having an average particle diameter of 0.5 to 50 μm. Such inorganic salts are easily obtained by pulverizing common inorganic salts.

  Moreover, it is preferable to set it as 8-20 parts with respect to 1 part of organic pigments (A) in conversion of mass, and, as for the usage-amount of the said inorganic salt, it is more preferable to set it as 10-15 parts.

  As the water-soluble organic solvent, those capable of suppressing the crystal growth can be suitably used. For example, diethylene glycol, glycerin, ethylene glycol, propylene glycol, liquid polyethylene glycol, liquid polypropylene glycol, 2- (methoxymethoxy) ethanol, 2-butoxy Ethanol, 2- (isopentyloxy) ethanol, 2- (hexyloxy) ethanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monomethyl ether, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether, 1,2-pro Or the like can be used Njioru but ethylene glycol or diethylene glycol are preferred.

  Although the usage-amount of the said water-soluble organic solvent is not specifically limited, 0.01-5 parts are preferable with respect to 1 part of organic pigments (A) in mass conversion.

  The kneading temperature is preferably between 60 and 150 ° C. When the organic pigment (A) is a copper phthalocyanine pigment, the ε conversion rate of ε type copper phthalocyanine (ε type crystallization rate contained in copper phthalocyanine) can be increased when the temperature is between 80 and 120 ° C. The surface-treated organic pigment thus obtained is preferable for use in color filters, since it is possible to reduce the decrease in heat resistance, contrast, etc., which will be described later.

  As an apparatus used for this kneading, a kneader or mix miller, Trimix (trade name) manufactured by Inoue Seisakusho Co., Ltd., which is a planetary mixer described in JP-A 2007-100008, or JP-A-4-122778 It is possible to use the continuous twin-screw extruder described above, Miracle KCK manufactured by Asada Iron Works Co., Ltd., which is a continuous single-screw kneader described in JP-A-2006-306996, and the like.

  When a phthalocyanine pigment is used as the organic pigment (A), a pressure heating method or a solvent salt milling method may be employed as a method of preparing the surface-treated organic pigment, but metal phthalocyanine as the organic pigment (A) When obtaining a surface-treated organic pigment containing a pigment, it is preferable to adopt the solvent salt milling method, and when obtaining a surface-treated organic pigment containing a halogenated metal phthalocyanine pigment as the organic pigment (A), It is preferable to employ a pressure heating method.

  The mixture subjected to heating in the liquid medium or heating and kneading under the pressure heating method or solvent salt milling method is cooled, for example, the liquid medium is removed therefrom, and if necessary, the solid is washed and filtered. By drying, pulverizing and the like, it is possible to obtain the powder of the surface-treated organic pigment of the present invention containing the organic pigment (A) and the copolymer (B) nonvolatile matter.

  As the washing, either water washing or hot water washing can be employed. The number of times of washing can be repeated within the range of 1 to 5 times. By washing, the copolymer (B) not adsorbed to the organic pigment (A) can be easily removed. If necessary, acid washing, alkali washing and solvent washing may be performed so as not to change the crystalline state. The amount of the copolymer (B) non-volatile component (so-called yield), which is an effective component, contained in the surface-treated organic pigment is determined, for example, from the amount of copolymer extraction by solvent extraction of the surface-treated organic pigment or It can be determined from the amount of outflow in the filtrate to the polymer (B).

  As the drying after the above-mentioned filtration and washing, for example, a batch-type or continuous-type drying of dehydrating and / or desolvating the pigment by heating at 80 to 120 ° C. by a heat source installed in a drier, etc. Examples of the dryer include a box dryer, a band dryer, and a spray dryer. In particular, spray drying is preferable because it is easily dispersed at the time of paste formation. In addition, pulverization after drying is not an operation for increasing the specific surface area or reducing the average particle size of primary particles, but, for example, the pigment is a lamp as in the case of drying using a box dryer or a band dryer. It is carried out in order to dissolve and pigment the pigment when it is in the form of lumps, for example, grinding with a mortar, a hammer mill, a disc mill, a pin mill, a jet mill or the like. Thus, a dry powder containing as a main component a surface-treated organic pigment containing the organic pigment (A) and the copolymer (B) is obtained.

  The surface-treated organic pigment of the present invention may contain an impurity such as a free metal or free metal ion source, but in the case where it is used to color a pixel portion of a color filter, the above-mentioned impurity is as small as possible. The smaller one is preferable. For example, when the organic pigment (A) is a phthalocyanine pigment, when the content of the metal ion source such as copper, zinc, copper ion and zinc ion is as small as possible, the liquid crystal display characteristics are adversely affected. It is preferable because it becomes difficult. The contained free metal may be the remaining free metal when synthesizing metal phthalocyanine, or may be generated by decomposition of metal phthalocyanine after synthesis.

  Such free metal and free metal ion sources can be washed with acids as described in JP-A-2008-308605. Examples of acids used include hydrochloric acid and sulfuric acid, and the concentration of hydrochloric acid or sulfuric acid is preferably 0.5% to 4%. Further, the temperature at the time of washing is preferably 50 to 90 ° C. It may also be washed with water.

  In the case of the surface-treated organic pigment of the present invention containing a metal phthalocyanine pigment as the organic pigment (A) in that the heat resistance of the color filter is small, the free metal content is 900 ppm in the surface-treated organic pigment by mass conversion. It is preferable that it is the following.

  The surface-treated organic pigment in the present invention has high dispersibility in the liquid medium, high dispersion stability, the viscosity of the pigment dispersion described later is low, and since it is dispersed in fine particles, Newtonian fluidity is also high. For example, when a color filter pixel portion is manufactured from this, it is possible to form a uniform coating film and obtain a color filter having high brightness, contrast and light transmittance.

  In the surface-treated organic pigment of the present invention thus obtained, the colored material upon coloring the medium to be colored is clear and excellent in chroma, and the hue of the colored material does not change significantly even if it receives a heat history over a long period of time Excellent in heat resistance. Therefore, it is suitable for coloring of paints, plastics, printing inks, rubbers, leathers, textiles, toners for electrophotography, inkjet inks, thermal transfer inks and the like as well as coloring of pixel parts of color filters.

  When the surface-treated organic pigment of the present invention is used to form a pixel portion of a color filter, the surface-treated organic pigment of the present invention containing a metal phthalocyanine pigment as the organic pigment (A) may be dioxazine, if necessary. A pigment can be further contained. The surface-treated organic pigment of the present invention containing a diketopyrrolopyrrole pigment as the organic pigment (A) can optionally contain an anthraquin pigment. The surface-treated organic pigment of the present invention containing a halogenated metal phthalocyanine pigment as the organic pigment (A) can contain a quinophthalone pigment or an organic metal complex pigment, if necessary.

  Furthermore, the surface-treated organic pigment of the present invention includes a sulfonic acid derivative of organic pigment (A), an N- (dialkylamino) methyl derivative, an N- (dialkylaminoalkyl) sulfonic acid amide derivative, and a phthalimidoalkyl derivative. And organic pigment derivatives and the like, DISKAVIC 130, DISKAVIC 161, DISPERKIC 162, DISPERKIC 163, DISPERKIC 170, DISPERKIC 171, DISPERKIC 174, DISPERBIC 180, DISPERBIC 182, DISPERBIC 183, and the like. , Disperbic 184, Disperbic 185, Disperbic 2000, Disperbic 2001, Disperbic 2020, Disperbic 2050, Disperbic 2070, Disper Tracks 2096, Disperbic 2150, Disperbic LPN 21116, Disperbic LPN 6919, Efka Efka 46, Efka 45, Efka LP 4008, Efka 4009, Efka LP 4010, Efka LP 4050, Efka LP 4055, Efka 400, Efka 401, Efka 402, Efka 403, Efka 450, Efka 453, Efka 4540, Efka LP 4560, Efka 120, Efka 150, Efka 1502, Efka 1503, Evuka 1503, Sul Sparse 3000, Sul Sparse 9000, Sul Sparse 13240 , Solsparse 13650, Solsparse 13940, Solsparse 17000, Solsparse 18000, Sols Source 20000, Sols sparse 21000, Sols sparse 20000, Sols sparse 24000, Sols sparse 26000, Sols sparse 28000, Sols sparse 28000, Sols sparse 32000, Sols sparse 36000, Sols sparse 37000, Sols sparse 38000, Sols sparse 41000, Sols sparse 42000, Sols sparse 43000, Sols sparse 46000, Sols spars 5s 71000, Ajinomoto Co., Ltd.'s Ajispar PB711, Ajisasper PB821, Azispar PB822, Azispar PB814, Azispar PN411, Azispar PA111, etc., dispersants such as acrylic resin, urethane resin, alkyd resin, wood rosin, gum rosin, tall oil rosin etc. Natural rosin, Polymerized rosin, disproportionated rosin, hydrogenated rosin, oxidized rosin, modified rosin such as rosin rosin, rosin amine, lime rosin, rosin alkylene oxide adduct, rosin alkyd adduct, rosin derivative such as rosin modified phenol etc at room temperature A liquid and water insoluble synthetic resin can be contained. The addition of the dispersant and the resin also contributes to the reduction of the flocculation, the improvement of the dispersion stability of the pigment, and the improvement of the viscosity characteristics of the dispersion.

  Although the surface-treated organic pigment of the present invention can be used in any of the known and commonly used applications, when it is contained in the pixel portion of a color filter, it preferably has an average primary particle diameter of 0.01 to 0.10 μm. If present, pigment aggregation is also relatively weak, and the dispersibility in the synthetic resin to be colored becomes better.

  The surface-treated organic pigment of the present invention described above or the surface-treated organic pigment obtained by the production method of the present invention is incorporated in the pixel portion of each color of R, G, B of the color filter to obtain a color filter It can. Specifically, for example, C.I. I. From the surface-treated organic pigment of the present invention containing a diketopyrrolopyrrole pigment such as C.I. I. From the surface-treated organic pigment of the present invention containing a halogenated metal phthalocyanine pigment such as C.I. I. B pixels can be obtained from the surface-treated organic pigment of the present invention containing a metal phthalocyanine pigment such as pigment blue 15: 6.

  As described above, the surface-treated organic pigment of the present invention can be used to form a pattern of R, G, B color pixel portions of a color filter by a known method. Typically, it is possible to obtain a photosensitive composition for a color filter pixel portion, which contains the surface-treated organic pigment for color filter of the present invention and a photosensitive resin as essential components.

  As a method for producing a color filter, for example, after the surface-treated organic pigment of the present invention is dispersed in a dispersion medium made of a photosensitive resin, glass, etc. can be produced by a slit coating method, spin coating method, roll coating method This method is called photolithography, which is applied on a transparent substrate and then subjected to pattern exposure with ultraviolet light through a photomask to the coated film, and then the unexposed area is washed with a solvent or the like to obtain each color pattern. It can be mentioned.

  In addition, a color filter may be manufactured by forming a pattern of each color pixel portion by an electrodeposition method, a transfer method, a micelle electrolysis method, or a PVED (photovoltaic electrodeposition) method. The surface-treated organic pigment of the present invention is very useful, for example, in a method of producing a color filter including baking in the process, because the hue change is small even when subjected to heat history.

  In order to prepare a photosensitive composition for a color filter pixel portion, for example, the surface-treated organic pigment of the present invention, a photosensitive resin, a photopolymerization initiator, and an organic solvent which dissolves the resin are mixed as essential components Do. As a method for producing the same, it is common to prepare a dispersion using the surface-treated organic pigment of the present invention, an organic solvent and, if necessary, a dispersing agent, and then adding a photosensitive resin or the like thereto to prepare it. is there.

  Examples of the dispersant used as required include Disperbyk (registered trademark) 130, Disperbyk 161, Disperbyc 162, Disperbyc 163, Disperbyk 170, Efka Efka 46, Efka 47, etc. Be In addition, leveling agents, coupling agents, cationic surfactants and the like can also be used.

  Examples of the organic solvent include aromatic solvents such as toluene, xylene and methoxybenzene, acetic acid ester solvents such as ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate, and ethoxy ethyl propionate Propionate solvents, alcohol solvents such as methanol and ethanol, ether solvents such as butyl cellosolve, propylene glycol monomethyl ether, diethylene glycol ethyl ether and diethylene glycol dimethyl ether, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, and fats such as hexane Hydrocarbon solvents, N, N-dimethylformamide, γ-butyrolactam, N-methyl-2-pyrrolidone, ani Emissions, nitrogen compound-based solvent such as pyridine, a lactone-based solvents such as γ- butyrolactone, carbamic acid esters such as a mixture of 48:52 of methyl carbamate and ethyl carbamate, there is water. As the organic solvent, a polar solvent such as propionate type, alcohol type, ether type, ketone type, nitrogen compound type, lactone type, water or the like and water soluble one is particularly suitable.

  300 to 1000 parts by mass of the organic solvent and, if necessary, 0 to 100 parts by mass of the dispersant and / or 0 to 20 parts by mass of the phthalocyanine derivative per 100 parts by mass of the surface-treated organic pigment of the present invention As a result, the dispersion can be obtained by stirring and dispersing. Subsequently, 3 to 20 parts by mass of the photosensitive resin, 0.05 to 3 parts by mass of the photopolymerization initiator per 1 part by mass of the photosensitive resin, and the necessary amount of the dispersion per 1 part by mass of the surface-treated organic pigment of the present invention An organic solvent is further added according to the conditions, and the mixture is stirred and dispersed so as to be uniform, whereby a photosensitive composition for color filter pixel can be obtained.

  Examples of photosensitive resins that can be used at this time include thermoplastic resins such as urethane resins, acrylic resins, polyamic acid resins, polyimide resins, styrene maleic acid resins, styrene maleic anhydride resins, and the like. Bifunctional monomers such as 1,6-hexanediol diacrylate, ethylene glycol diacrylate, neopentyl glycol diacrylate, triethylene glycol diacrylate, bis (acryloxyethoxy) bisphenol A, 3-methylpentanediol diacrylate, etc. Trimethyl roll propaton triacrylate, pentaerythritol triacrylate, tris (2-hydroxyethyl) isocyanate, dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate It includes photopolymerizable monomers such as polyfunctional monomers such as.

  As the photopolymerization initiator, for example, acetophenone, benzophenone, benzyl dimethyl ketal, benzoyl peroxide, 2-chlorothioxanthone, 1,3-bis (4'-azidobenzal) -2-propane, 1,3-bis (4'-) Azidobenzal) -2-propane-2'-sulfonic acid, 4,4'-diazide stilbene-2,2'-disulfonic acid and the like.

  The thus prepared photosensitive composition for a color filter pixel portion may be formed into a color filter by performing pattern exposure with ultraviolet light through a photomask and then washing an unexposed portion with an organic solvent, alkaline water or the like. it can.

  Hereinafter, the present invention will be specifically described using Synthesis Examples, Comparative Synthesis Examples, Examples, and Comparative Examples. In these examples, "%" shall mean mass percent.

Synthesis Example 1
In a four-necked flask equipped with a stirrer, thermometer, condenser and nitrogen inlet tube, 1540 parts of propylene glycol monomethyl ether acetate is charged, and the temperature is raised to 110 ° C. under a nitrogen stream, then 623 parts of methyl methacrylate, n-butyl A mixed solution consisting of 307 parts of methacrylate, 70 parts of glycidyl methacrylate and 18 parts of t-butylperoxy-2-ethylhexanoate (hereinafter abbreviated as TBPEH) was dropped over 4 hours. After completion of the dropwise addition, reaction was carried out at 110 ° C. for 7 hours to obtain a solution of a copolymer (B-1) having a nonvolatile content of 40.5% and a weight average molecular weight of 16,000.

(Composition example 2)
1540 parts of propylene glycol monomethyl ether acetate is charged into the same four-necked flask as in Synthesis Example 1, and the temperature is raised to 110 ° C. under nitrogen stream, then 597 parts of methyl methacrylate, 261 parts of n-butyl methacrylate, 142 parts of glycidyl methacrylate And a mixture of 18 parts of TBPEH was added dropwise over 4 hours. After completion of the dropwise addition, reaction was carried out at 110 ° C. for 7 hours to obtain a solution of a copolymer (B-2) having a nonvolatile content of 39.8% and a weight average molecular weight of 15,000.

(Composition example 3)
1540 parts of propylene glycol monomethyl ether acetate is charged into the same four-necked flask as in Synthesis Example 1, and the temperature is raised to 110 ° C. under nitrogen stream, then 547 parts of methyl methacrylate, 173 parts of n-butyl methacrylate, 280 parts of glycidyl methacrylate And a mixture of 18 parts of TBPEH was added dropwise over 4 hours. After completion of the dropwise addition, the mixture was reacted at 110 ° C. for 7 hours to obtain a solution of a copolymer (B-3) having a nonvolatile content of 40.0% and a weight average molecular weight of 16,000.

(Composition example 4)
1540 parts of propylene glycol monomethyl ether acetate is charged into the same four-necked flask as in Synthesis Example 1, and the temperature is raised to 110 ° C. under a nitrogen stream, and then a mixed liquid consisting of 856 parts of benzyl methacrylate, 142 parts of glycidyl methacrylate and 18 parts of TBPEH. Was dripped over 4 hours. After completion of the dropwise addition, the reaction was carried out at 110 ° C. for 7 hours to obtain a solution of a polymer (B-4) having a nonvolatile content of 38.1% and a weight average molecular weight of 14,000.

(Composition example 5)
The solution of the polymer (B-2) of Synthesis Example 2 is dried under reduced pressure (60 ° C., 10 hours), and the solid of the polymer (B-2) obtained is reacted with hydrochloric acid to obtain a polymer (B). The polymer (B-5) in which the epoxy group in -2) was ring-opened to give an α-chlorohydrin form was obtained.

Synthesis Example 6
1540 parts of propylene glycol monomethyl ether acetate is charged into the same four-necked flask as in Synthesis Example 1, and the temperature is raised to 110 ° C. under a nitrogen stream, and then it comprises 597 parts of methyl methacrylate, 261 parts of n-butyl methacrylate and 18 parts of TBPEH. The mixture was dropped over 4 hours. After completion of the dropwise addition, reaction was carried out at 110 ° C. for 7 hours to obtain a solution of a copolymer (B-6) having a nonvolatile content of 39.8% and a weight average molecular weight of 15,000.

  10 g of FASTOGEN GREEN A110 (polybrominated zinc phthalocyanine pigment manufactured by DIC Corporation) and 1.25 g of the copolymer (B-1) solution (the solid content 40.5%) of the above-mentioned Synthesis Example 1 together with 589 g of water The mixture was charged in a 1-liter autoclave, heated to 130 ° C. in 1 hour while stirring, and maintained at that temperature for 1 hour to carry out resin treatment on the pigment surface. After cooling to room temperature, suction filtration and washing with 2 liters of warm water were carried out. The obtained wet cake was dried at 90 ° C. for 12 hours, and ground by a lab mill to obtain a surface-treated organic pigment (X-1) having an average particle diameter of 100 nm or less of primary particles.

  The copolymer (B-2) solution (Synthesis example 2) solution (B-2) solution (Synthesis 4) solution (solid content 40.5%) solution (Comb. A surface-treated organic pigment (X-2) having an average particle diameter of 100 nm or less of primary particles was obtained in the same manner as in Example 1 except that solid content 39.8% was used.

  The copolymer (B-3) solution (Synthesis example 3) solution (B-3) solution (Synthesis 4) solution (solid content 40.5%) 1.25 g is made the same amount as non-volatile matter. A surface-treated organic pigment (X-3) having an average particle diameter of 100 nm or less of primary particles was obtained in the same manner as in Example 1 except that solid content of 39.8% was used.

(Comparative example 1)
Hydrane AP-40F (Polyurethane resin aqueous dispersion manufactured by DIC Corporation) so that 1.25 g of the copolymer (B-1) solution (solid content 40.5%) of Synthesis Example 1 is equivalent in non-volatile content A surface-treated organic pigment (X-4) was obtained in the same manner as in Example 1 except that the solution was used.

2.48 parts of the surface-treated organic pigment (X-1) obtained in Example 1 above, 1.24 parts of BYK-LPN6919 (Bicchemy dispersant) manufactured by Bick Chemie, Unidic ZL 295 (acrylic resin manufactured by DIC Corporation) 1.) Using 0.3 to 0.4 mm zircon beads together with 1.86 parts and 10.92 parts of propylene glycol monomethyl ether acetate, the particles were dispersed for 2 hours with a paint conditioner manufactured by Toyo Seiki Co., Ltd.
To form a green pixel part for a color filter by adding 4.0 parts of this coloring composition (I), 2.10 parts of Unidic ZL 295 and 2.00 parts of propylene glycol monomethyl ether acetate and mixing them with a paint conditioner The composition for evaluation of was obtained.
The composition for evaluation was spin-coated on soda glass while changing the film thickness, and dried at 90 ° C. for 3 minutes to obtain a glass substrate for evaluation. Using this glass substrate, the chromaticity (x, y) of the C light source was measured by MCPD-3000 manufactured by Otsuka Electronics Co., Ltd. Further, the chromaticity after heating the evaluation glass substrate at 230 ° C. for 1 hour was also measured.

  Example 4 except that the same amount of the surface-treated organic pigment (X-2) obtained in Example 2 is used instead of 2.48 parts of the surface-treated organic pigment (X-1) obtained in Example 1 above A series of operations were performed in the same manner as in to obtain a glass substrate for evaluation, and the measurement was performed in the same manner.

  Example 4 except that the same amount of the surface-treated organic pigment (X-3) obtained in Example 3 is used instead of 2.48 parts of the surface-treated organic pigment (X-1) obtained in Example 1 above A series of operations were performed in the same manner as in to obtain a glass substrate for evaluation, and the measurement was performed in the same manner.

(Comparative example 2)
Example 4 except that the same amount of the surface-treated organic pigment (X-4) obtained in Comparative Example 1 is used instead of 2.48 parts of the surface-treated organic pigment (X-1) obtained in Example 1 above A series of operations were performed in the same manner as in to obtain a glass substrate for evaluation, and the measurement was performed in the same manner.

  The evaluation results of Examples 4 to 6 and Comparative Example 2 are shown in Table 1. After PB in the table means after heating at 230 ° C. for 1 hour.

As can be seen from the comparison between Example 4 and Comparative Example 1 in Table 1 above, the specific copolymer (B) used in the present invention has an initial and after PB compared to the polyurethane resin used conventionally. It is apparent that the difference between the luminance value and the chromaticity value is small, and the variation of the luminance and the chromaticity is small even under heat history, and the heat resistance is excellent.
In each of Examples 4 to 6, both the luminance and the chromaticity are improved as an absolute value after PB in comparison with the initial state, and the side chain epoxy group occupied in the specific copolymer (B) at the time of preparation There was a tendency that the absolute value of the initial luminance increased as the content rate of

85 parts of FASTOGEN BLUE AE-8 (ε-type copper phthalocyanine pigment manufactured by DIC Corporation), 5 parts of copper phthalocyanine phthalimidomethyl derivative having an average substituent number of 1.4, and a solution of the polymer (B-2) of Synthesis Example 2 are decompressed 10 parts of solid of polymer (B-2) obtained by drying (60 ° C., 10 hours), 1000 parts of crushed sodium chloride, and 160 parts of diethylene glycol are charged in a double-arm kneader, 10 at 80-90 ° C. Knead for time.
The resulting content is washed with a large excess of water, filtered, and washed with water until the specific conductivity of the filtrate becomes (specific conductivity of the raw water + 20 μS / cm or less), to obtain an ε-type copper phthalocyanine surface-treated organic pigment The wet cake of The obtained wet cake was transferred to a beaker, and 3000 parts of 2% hydrochloric acid aqueous solution was added thereto, and dispersed by stirring to obtain a slurry. The mixture was stirred at 70 ° C. for 1 hour, filtered and washed with water to obtain a wet cake.
The obtained wet cake was transferred to a beaker, 3000 parts of water at room temperature was added, and the mixture was stirred and dispersed to obtain a slurry. Subsequently, an aqueous sodium hydroxide solution of 5 parts of a copper phthalocyanine sulfonic acid derivative having an average substituent number of 0.8 is added to the pigment slurry, and after stirring for 1 hour, hydrochloric acid is added to return the pH of the slurry to 7 and It was deposited on the surface. After holding as it is for 1 hour, it is filtered, washed with warm water, dried and pulverized to obtain a blue surface-treated organic pigment having an average particle diameter of 100 nm or less of primary particles.

10 parts of the blue surface-treated organic pigment thus obtained is put in a polybin, 55 parts of propylene glycol monomethyl ether acetate, 7.0 parts of BYK (trade name) LPN 21116 (manufactured by Bick Chemie Co., Ltd.), 0.3-0 .4 mm φ seple beads were added, and dispersed with a paint conditioner (manufactured by Toyo Seiki Co., Ltd.) for 4 hours to obtain a pigment dispersion. 75.00 parts of this pigment dispersion and 5.50 parts of polyester acrylate resin (ALONIX.RTM. M7100, manufactured by Toa Synthetic Chemical Industry Co., Ltd.), dierythritol erythritol hexaacrylate (KAYARAD.TM. DPHA, Nippon Kayaku Co., Ltd. A dispersion stirrer is used to stir 5.00 parts of KK Co., Ltd., 1.00 parts of benzophenone (KAYACURE (trade name) BP-100, manufactured by Nippon Kayaku Co., Ltd.), 13.5 parts of Euker Ester EEP with a dispersion stirrer, and the pore diameter is 1.0 μm. The solution was filtered through a filter of to obtain a color resist. This color resist was coated on a 50 mm × 50 mm, 1 mm thick glass using a spin coater so that the dry film thickness would be 2 μm, and then predried at 90 ° C. for 20 minutes to form a coating. Then, after pattern exposure with ultraviolet light was performed through a photomask, the unexposed portion was washed in a 0.5% aqueous solution of sodium carbonate and baked at 230 ° C. for 60 minutes to obtain a color filter.

It was 13.49 when luminance Y in C light source was measured by Otsuka Electronics Co., Ltd. product MCPD-3000 using the color filter obtained in this way. In addition, the luminance after heating the color filter at 230 ° C. for 1 hour was 13.42.

  A blue surface-treated organic pigment is obtained in the same manner as in Example 7 except that the polymer (B-2) in Example 7 is used instead of the polymer (B-2), and a color filter is produced using it. When the luminance Y in the C light source was measured, the luminance before heating at 230 ° C. for one hour was 13.50, and the luminance after heating at 230 ° C. for one hour was 13.43.

(Comparative example 3)
A blue surface-treated organic pigment is obtained in the same manner as in Example 7 except that the polymer (B-2) is used instead of the polymer (B-2) in Example 7, and a color filter is produced using it. When the luminance Y in the C light source was measured, the luminance before heating at 230 ° C. for one hour was 13.45, and the luminance after heating at 230 ° C. for one hour was 13.26.

The evaluation results of Examples 7 to 8 and Comparative Example 3 are shown in Table 2.

  According to the present invention, the specific heat resistance due to the interaction between the organic pigment (A) and the specific copolymer (B) makes it possible to provide a colored product having a small change in hue even when subjected to a heat history. When used for preparation of the pixel portion of the filter, it is possible to provide a liquid crystal display device which has high luminance and can perform liquid crystal display with excellent luminance even if heat history is received for a long time.

Claims (4)

It contains 0.1 to 15 parts of a polymer (B) obtained by polymerizing a monomer mixture containing methyl methacrylate, n-butyl methacrylate, and glycidyl methacrylate per 100 parts of the organic pigment (A) in terms of mass. Surface-treated organic pigment for color filter characterized in that. The organic pigment (A) is, according to claim 1 color surface treatment organic pigments filter according phthalocyanine pigment. In a liquid medium, or polymer of claim 1 (B) a phthalocyanine pigment in the presence of a non-volatile content (A) pressurizing heating, or the presence of the polymer (B) non-volatile matter of claim 1 the process according to claim 1 color surface treatment organic pigments filter according to solvent salt milling an organic pigment (a) below. A color filter comprising the surface-treated organic pigment for color filter according to claim 1 or 2 in a pixel portion.