JP2005292305A - Color composition using complementary color pigment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stable color composition free from production of pigment coarse particles due to dissolution or recrystallization of a dye lake pigment, even if a color composition for a color filter of a color imaging device is manufactured by using a dye lake pigment C.I.Pigment Red 81:2, which is superior in spectral characteristics and light resistance to a magenta dye but is inferior in solvent resistance. <P>SOLUTION: The color composition comprises a pigment carrier comprising a transparent resin, its precursor or their mixture, a dye lake pigment C.I.Pigment Red 81:2 and an organic solvent, having ≤9.0 solubility parameter, preferably of 6.0 to 9.0. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a coloring composition used for manufacturing a color filter of a color image sensor represented by C-MOS, CCD and the like.

2. Description of the Related Art In recent years, color image sensors such as CCDs have reduced the amount of light that can be received due to a reduction in area per pixel due to downsizing and high pixel count of the image sensor, leading to a decrease in sensitivity. In order to compensate for this, a condensing microlens is generally formed on the light receiving element. However, with the progress of higher definition and higher pixels, it has become impossible to obtain sufficient sensitivity only with the light condensing effect of the microlens.
A color image pickup device such as a CCD performs color separation by disposing color filters each having a primary color filter segment of additive mixture of B (blue), G (green), and R (red) on the light receiving element. Is common. By using this additive mixed primary color filter, easy color separation and good color reproduction can be obtained, but the B (blue), G (green), and R (red) filter segments are each near the dominant wavelength. There is only a light transmission region in a narrow range, and this is one of the causes of sensitivity reduction.

On the other hand, a complementary color filter having filter segments of Y (yellow), M (magenta), and C (cyan) corresponding to complementary colors of B (blue), G (green), and R (red) High sensitivity can be obtained compared to color filters. For this reason, high-definition image sensors with 3 million pixels and 6 million pixels, low-cost image sensors that aim to reduce costs by attaching multiple faces to a semiconductor wafer (use as many small chip elements as possible), and auxiliary light sources such as flash In video cameras that are difficult to perform, complementary color filters are being adopted.
In the case of a complementary color filter, in order to create primary color information (spectral characteristics) from complementary color information (spectral characteristics), in addition to the three colors Y (yellow), M (magenta), and C (cyan), G (Green) is added to obtain four colors, and G (green) may be created by overlapping two colors of C (cyan) and Y (yellow).

  However, the complementary color pigment used in the complementary color filter has a very narrow range of selection, so it is difficult to obtain a complementary color pigment having excellent spectral characteristics, and this has excellent color reproducibility with an imaging device employing a complementary color filter. It was one of the reasons why it was difficult to get. In particular, the spectral characteristics of magenta are insufficient. For example, C.I. which is a quinacridone-based magenta pigment. I. Pigment Red 122 has a low transmittance on the short wavelength side (400 to 500 nm) and tends to break the color balance. As a magenta dye used in complementary color filters, rhodamine, which is a basic dye, has excellent spectral characteristics compared to the magenta pigments, but has extremely low light resistance and high reliability as well as dyes used in primary color filters. Is insufficient for applications such as PDAs, digital cameras, and video cameras.

As a method for improving the drawbacks of the magenta pigment and the magenta dye, rake formation of the dye is known. In this method, the dye is precipitated and fixed on the extender pigment with an appropriate precipitating agent to form an insoluble form in water, and is generally used as a dyed lake pigment or dyed lake pigment.
However, a coloring composition in which a dyed lake pigment is dispersed in a resin solution has a problem of poor dispersion stability. The coarse particles of the dyed rake pigment generated as a result of poor dispersion stability have become smaller in size of one pixel due to downsizing and higher definition of the image sensor, which is a cause of image sensor defects such as missing pixels. It has become.
JP 2001-81348 A

  An object of the present invention is to provide a coloring composition having excellent spectral characteristics and good dispersion stability, which is used in the production of a complementary color filter constituting a color imaging device. Another object of the present invention is to provide a complementary color filter having good color reproducibility without defects due to pigment elementary particles in the magenta color filter segment.

The coloring composition of the present invention includes C.I. I. Pigment Red 81: 2 pigment, an organic solvent having a solubility parameter of 9.0 or less, preferably 6.0 to 9.0, and a pigment carrier made of a transparent resin, a precursor thereof, or a mixture thereof. Features.
The color filter of the present invention is a color filter comprising a magenta color filter segment, a cyan color filter segment, and a yellow color filter segment, and the magenta color filter segment is formed using the colored composition of the present invention. It is characterized by.

  The coloring composition of the present invention has good spectral characteristics but low solvent resistance. I. Since Pigment Red 81: 2 pigment is dispersed in an organic solvent that does not dissolve the pigment, it has high transparency and dispersion stability. Therefore, by using the colored composition of the present invention, it is possible to obtain an excellent color filter free from filter segment defects caused by coarse particles in the colored composition.

First, the coloring composition of the present invention will be described in detail.
The coloring composition of the present invention includes C.I. I. Pigment Red 81: 2 pigment, an organic solvent having a solubility parameter of 9.0 or less, and a pigment carrier.
C. I. Pigment Red 81: 2 pigment is a W.W. Herbst, K.M. A dye lake pigment described on pages 558 to 560 of "Industrial Organic Pigments (Second Edition)" by Hunger and sold as "FANAL ROSE D4830" by BASF.
C. I. Pigment Red 81: 2 pigment is preferably contained in the coloring composition in a proportion of 1.5 to 7% by weight. In addition, C.I. I. Pigment Red 81: 2 pigment is preferably contained in the final filter segment in a proportion of 10 to 40% by weight, more preferably 20 to 40% by weight, the balance of which is substantially from the resinous binder provided by the pigment carrier. Become.

  The organic solvent constituting the coloring composition is C.I. I. Pigment Red 81: 2 The solubility and compatibility of the pigment carrier in which the pigment is dispersed, and C.I. I. Pigment Red 81: 2 The solubility parameter must be 9.0 or less in consideration of the stability and coating property of the coloring composition that can maintain a stable dispersion state without dissolving or aggregating the pigment. C. I. Pigment Red 81: 2 pigment has solvent selectivity, and when the coloring composition is prepared with an organic solvent having a solubility parameter exceeding 9.0, C.I. I. Pigment Red 81: 2 causes problems such as dissolving or agglomerating the pigment.

  The solubility parameter is a value obtained from the solubility parameter of Hildebrand, which is often used when evaluating the ease of dissolution of the non-electrolyte in an organic solvent. For this solubility parameter, see J.H. H. Hildebrand, J.M. M, Prausnitz. R. L. It is described in detail in “Regular and Relanted Solutions” by Scott, Van Nostrand-Reinhold, Princeton (1970), “Polymer Data Handbook Fundamentals”, Polymer Society, etc.

One organic solvent can be used alone, or two or more organic solvents can be used in combination. When two or more organic solvents are mixed, the solubility parameter of the mixed solvent may be 9.0 or less.
The solubility parameter δ of the mixed solvent is obtained by the following equation.
δ = (X1 V1 δ1 + X2 V2 δ2 + ... XnVnδn) / (X1 V1 + X2 V2 + ... XnVn)
Here, Xn is the molar fraction of the constituent solvent, Vn is the molar volume of the constituent solvent, and δn is the solubility parameter of the constituent solvent.

Examples of the organic solvent include hydrocarbons such as benzene (solubility parameter: 9.2), toluene (8.9), xylene (8.8), and octane (7.6), methyl alcohol (14.5). , Ethyl alcohol (12.7), n-butyl alcohol (11.4), ethyl cellosolve (10.5), butyl cellosolve (9.5), carbitol (10.2), butyl carbitol (9.5) Alcohols such as acetone (9.9), methyl ethyl ketone (9.3), methyl isobutyl ketone (8.4), diisobutyl ketone (7.8), cyclohexanone (9.9) and the like, ethyl acetate ( 9.1), n-butyl acetate (8.5), isobutyl acetate (8.3), isoamyl acetate (7.8), methoxypropyl acetate (9.2) and other vinegar And esters, and the like.
Especially, C.I. I. Pigment Red 81: 2 pigment is preferable because it can be stably dispersed without dissolving or aggregating the pigment, and an acetate solvent is preferable, and isoamyl acetate is particularly preferable. Further, a mixed solvent composed of isoamyl acetate and methoxypropyl acetate is more preferable because it is excellent in viscosity and transparency.

Although content of the organic solvent in a coloring composition is determined by coating conditions etc., 30 to 97 weight% is preferable on the basis of the weight of a coloring composition, and 40 to 80 weight% is more preferable.
Moreover, when mixing and using isoamyl acetate and methoxypropyl acetate, it is preferable that isoamyl acetate is 16 to 98% by weight, methoxypropyl acetate is preferably 2 to 84% by weight, and isoamyl acetate is 20 to 80% by weight. %, And methoxypropyl acetate is more preferably 20 to 80% by weight.

The pigment carrier is made of a transparent resin, a precursor thereof, or a mixture thereof.
The transparent resin includes a thermoplastic resin, a thermosetting resin, and an active energy ray curable resin, and a precursor thereof is a photopolymerizable monomer or oligomer that is cured by irradiation with an active energy ray to produce a transparent resin. These can be used alone or in admixture of two or more. When the composition is cured by ultraviolet irradiation, a photopolymerization initiator or the like is added to the colored composition.

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

  As the active energy ray-curable resin, a (meth) acryl having a reactive substituent such as an isocyanate group, an aldehyde group or an epoxy group on a linear polymer having a reactive substituent such as a hydroxyl group, a carboxyl group or an amino group. A resin in which a photocrosslinkable group such as a (meth) acryloyl group or a styryl group is introduced into the linear polymer by reacting a compound or cinnamic acid is used. Further, a linear polymer containing an acid anhydride such as a styrene-maleic anhydride copolymer or an α-olefin-maleic anhydride copolymer is converted into a (meth) acrylic compound having a hydroxyl group such as hydroxyalkyl (meth) acrylate. Half-esterified products are also used.

  Photopolymerizable monomers and oligomers include methyl (meth) acrylate, ethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, cyclohexyl (meth) acrylate, β-carboxyethyl ( (Meth) acrylate, polyethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate , Pentaerythritol tri (meth) acrylate, 1,6-hexanediol diglycidyl ether di (meth) acrylate, bisphenol A diglycidyl ether di (meth) acrylate , Neopentyl glycol diglycidyl ether di (meth) acrylate, dipentaerythritol hexa (meth) acrylate, tricyclodecanyl (meth) acrylate, ester acrylate, methylolated melamine (meth) acrylate, epoxy (meth) Acrylic esters and methacrylic esters such as acrylate and urethane acrylate, (meth) acrylic acid, styrene, vinyl acetate, hydroxyethyl vinyl ether, ethylene glycol divinyl ether, pentaerythritol trivinyl ether, (meth) acrylamide, N-hydroxymethyl ( Examples include meth) acrylamide, N-vinylformamide, acrylonitrile, and the like, and these can be used alone or in combination of two or more.

  The pigment carrier has an acrylic resin and a photopolymerizable monomer or oligomer in order to impart high transparency, dispersion stability of the pigment, and suitable properties such as adhesion, solvent resistance, heat resistance, and developability with a resist. And a mixture thereof.

  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.

  The above photopolymerization initiators are used alone or in combination of two or more. As sensitizers, α-acyloxy ester, acylphosphine oxide, methylphenylglyoxylate, benzyl, 9,10-phenanthrenequinone. , Camphorquinone, ethylanthraquinone, 4,4′-diethylisophthalophenone, 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone, 4,4′-diethylaminobenzophenone, etc. It can also be used together.

The colored composition of the present invention can be prepared in the form of a solvent development type or alkali development type colored resist. The colored resist is obtained by dispersing a pigment in a pigment carrier containing a thermoplastic resin, a thermosetting resin or a photosensitive resin and a monomer. In the pigment carrier, a three-roll mill, a two-roll mill, a sand mill, a kneader, Using various dispersing means such as an attritor, the pigment can be finely dispersed with a photopolymerization initiator as necessary. The colored composition of the present invention can also be produced by mixing several types of pigments separately dispersed on a pigment carrier in order to adjust the spectral characteristics.
When dispersing the pigment in the pigment carrier, a dispersion aid such as a resin-type pigment dispersant and a surfactant can be appropriately used. The dispersion aid is excellent in dispersing the pigment and has a great effect of preventing re-aggregation of the pigment after dispersion. Therefore, when a coloring composition obtained by dispersing the pigment in the pigment carrier using the dispersion aid is used. Provides a color filter excellent in transparency.

  The resin-type pigment dispersant has a pigment affinity part that has the property of adsorbing to the pigment and a part that is compatible with the pigment carrier, and acts to stabilize the dispersion of the pigment on the pigment carrier by adsorbing to the pigment. It is something to do. Specific examples of resin-type pigment dispersants include polycarboxylic acid esters such as polyurethane and polyacrylate, unsaturated polyamides, polycarboxylic acids, polycarboxylic acid (partial) amine salts, polycarboxylic acid ammonium salts, and polycarboxylic acid alkylamines. Salts, polysiloxanes, long-chain polyaminoamide phosphates, hydroxyl group-containing polycarboxylic acid esters, their modified products, amides formed by the reaction of poly (lower alkyleneimines) with polyesters having free carboxyl groups, and the like Water-based dispersants such as oily dispersants such as salts, (meth) acrylic acid-styrene copolymers, (meth) acrylic acid- (meth) acrylic acid ester copolymers, styrene-maleic acid copolymers, polyvinyl alcohol, polyvinylpyrrolidone Resin, water-soluble polymer, polyester Modified polyacrylate, ethylene oxide / propylene oxide addition compound, phosphate ester-based and the like are used, they can be used alone or in admixture of two or more.

  Surfactants include sodium lauryl sulfate, polyoxyethylene alkyl ether sulfate, sodium dodecylbenzene sulfonate, alkali salt of styrene-acrylic acid copolymer, sodium stearate, sodium alkyl naphthalene sulfonate, sodium alkyl diphenyl ether disulfonate. , Lauryl sulfate monoethanolamine, lauryl sulfate triethanolamine, ammonium lauryl sulfate, monoethanolamine stearate, sodium stearate, sodium lauryl sulfate, monoethanolamine of styrene-acrylic acid copolymer, polyoxyethylene alkyl ether phosphate Anionic surfactants such as: polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene Nonionic surfactants such as nylphenyl ether, polyoxyethylene alkyl ether phosphate ester, polyoxyethylene sorbitan monostearate, polyethylene glycol monolaurate; chaotic properties such as alkyl quaternary ammonium salts and their ethylene oxide adducts Surfactants: Examples include amphoteric surfactants such as alkylbetaines such as alkyldimethylaminoacetic acid betaine and alkylimidazolines, and these can be used alone or in admixture of two or more.

In addition, the colored composition of the present invention can contain a storage stabilizer in order to stabilize the viscosity with time of the composition. Examples of storage stabilizers include quaternary ammonium chlorides such as benzyltrimethyl chloride and diethylhydroxyamine, organic acids such as lactic acid and oxalic acid, and organic acids such as methyl ether, t-butylpyrocatechol, tetraethylphosphine, and tetraphenylphosphine. Examples thereof include phosphine and phosphite.
The colored composition of the present invention is prepared by means of centrifugation, sintered filter, membrane filter or the like, coarse particles of 1 μm or more, preferably coarse particles of 0.6 μm or more, more preferably coarse particles of 0.2 μm or more and It is preferable to remove the mixed dust.

Next, the color filter of the present invention will be described.
The color filter of the present invention is a color filter comprising a magenta color filter segment, a cyan color filter segment, and a yellow color filter segment, and the magenta color filter segment is formed using the colored composition of the present invention. In addition to the above three colors, G (green) or other colors may be added.
The cyan filter segment can be formed using a normal cyan coloring composition. Examples of the cyan coloring composition include C.I. I. Pigment Blue 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 22, 60, 64 and the like can be used, and among these, C.I. of the copper phthalocyanine pigment can be used. I. Pigment Blue 15, 15: 1, 15: 2, 15: 3, 15: 4, and 15: 6 are preferable.

  The yellow filter segment can be formed using a normal yellow coloring composition. Examples of the yellow coloring composition include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 24, 31, 32, 34, 35, 35: 1, 36, 36: 1, 37, 37: 1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 123, 126, 127, 128, 129, 138, 139, 147, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180 , 181, 182, 185, 187, 188, 193, 194, 198, 199, 213, 214, and the like can be used.

  Moreover, a green filter segment can be formed using a normal green coloring composition. Examples of the green coloring composition include C.I. I. This is a composition obtained using a green pigment such as Pigment Green 7, 10, 36, 37. The green pigment can be used in combination with the yellow pigment. The green filter segment can be formed from a green colored composition obtained by mixing the cyan colored composition and the yellow colored composition. Furthermore, the green filter segment can be formed by overlapping a coating film formed from the cyan coloring composition and a coating film formed from the yellow coloring composition.

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

  When each color filter segment is formed by photolithography, the colored composition prepared as the solvent development type or alkali development type color resist is spray-coated or spin-coated on a silicon wafer provided with transfer electrodes and photodiodes. It applies so that a dry film thickness may be set to 0.2-5 micrometers by application | coating methods, such as a slit coat and a roll coat. If necessary, the dried film is exposed to ultraviolet light through a mask having a predetermined pattern provided in contact with or non-contact with the film. Then, after immersing in a solvent or alkali developer or spraying the developer by spraying or the like to remove the uncured portion to form a desired pattern, the same operation is repeated for other colors to produce a color filter. be able to. Furthermore, in order to accelerate the polymerization of the colored resist, heating can be performed as necessary. According to the photolithography method, a color filter with higher accuracy than the above printing method can be manufactured.

In development, an aqueous solution such as sodium carbonate or sodium hydroxide is used as an alkali developer, and an organic alkali such as dimethylbenzylamine or triethanolamine can also be used. Moreover, an antifoamer and surfactant can also be added to a developing solution.
In order to increase the UV exposure sensitivity, after coating and drying the colored resist, a water-soluble or alkaline water-soluble resin such as polyvinyl alcohol or a water-soluble acrylic resin is applied and dried to form a film that prevents polymerization inhibition by oxygen. Thereafter, ultraviolet exposure can also be performed.
The color filter of the present invention can be produced by a transfer method or the like in addition to the above method, but the colored composition of the present invention can be used in any method. The transfer method is a method in which a color filter layer is formed in advance on the surface of a peelable transfer base sheet, and this color filter layer is transferred onto a silicon wafer provided with desired transfer electrodes and photodiodes.

  EXAMPLES The present invention will be described in more detail with reference to the following examples. However, the following examples do not limit the scope of rights of the present invention. In the examples, “part” represents “part by weight”. First, various evaluation methods performed in Examples will be described. Various evaluations were carried out after the pigment dispersion and the resist were packed in a sealed container and allowed to stand in a 40 ° C. oven for 7 days, and the results are shown in the table as accelerated aging. As for the pass / fail judgment for the accelerated time, the rate of change within 10% of the initial value was judged to be good.

(1) Appearance of pigment dispersion and resist According to JIS K 5600-1-1-4.1a), when there is no viscous anomaly and there is no pigment aggregation, ○, when pigment aggregation is observed due to poor viscosity, The case was determined to be Δ.
(2) Viscosity of Pigment Dispersion Using a B-type viscometer (BL type manufactured by Toki Sangyo Co., Ltd.), the viscosity at No. 2 rotor, 6 rpm, 25 ° C. was measured.
(3) Viscosity of Resist Using an E-type viscometer (TV 20 type, manufactured by Toki Sangyo Co., Ltd.), the viscosity at 1 ° 34 ′ × R24 cone, rotation speed 50 rpm, and 25 ° C. was measured.

(4) 630 nm transmittance of the pigment dispersion coating film and the resist coating film The pigment dispersion and the resist are dried on a washed and dried 100 × 100 × 0.7 mm glass substrate so that the dry film thickness becomes 1.5 μm by a spin coater. It was applied and dried at 80 ° C. for 30 minutes. Using a microspectrophotometer ("OSP-SP100" manufactured by Olympus Optical Co., Ltd.), the transmittance of the obtained coating film was measured at 630 nm.
(5) Number of particles of 2 μm or more of pigment dispersion coating film and resist coating film About the coating film prepared in the same manner as (4), using a microscope (“Digital HF Microscope VH8000” manufactured by Keyence Corporation), 450 An image of 4 times (1 field: 200 × 200 μm) was binarized and the number of particles of 2 μm or more was measured. It was determined that the average number of particles in 4 fields was 0 at the initial stage and 2 or less in the accelerated aging.

(Production of resin solution)
Production examples of resin solutions used for pigment dispersion and resist preparation are shown below.
800 parts of isoamyl acetate are put into a reaction vessel and heated to 100 ° C. while injecting nitrogen gas into the vessel. At the same temperature, 60.0 parts of styrene, 60.0 parts of methacrylic acid, 65.0 parts of methyl methacrylate, methacrylic acid A mixture of 65.0 parts of butyl and 10.0 parts of azobisbutyronitrile was added dropwise over 1 hour to carry out polymerization. After the dropwise addition, the mixture was further reacted at 100 ° C. for 3 hours, then 2.0 parts of azobisisobutyronitrile dissolved in 50 parts of isoamyl acetate was added, and the reaction was further continued for 1 hour to obtain an acrylic resin solution. It was. The weight average molecular weight of the acrylic resin was about 40,000 (measured by GPC). After cooling the obtained acrylic resin solution to room temperature, a part of the resin solution was sampled and heated and dried at 180 ° C. for 20 minutes to measure the non-volatile content, so that the non-volatile content was 20% by weight. An acrylic resin solution A (isoamyl acetate solution) was prepared by adding isoamyl acetate to the obtained resin solution.
The solvent was changed to methoxypropyl acetate and cyclohexanone, and the reaction and adjustment were performed in the same manner as described above, and acrylic resin solution B (methoxypropyl acetate solution) having a nonvolatile content of 20% by weight and acrylic resin solution C (cyclohexanone having a nonvolatile content of 20% by weight). Solution).

[Examples 1-4 and Comparative Examples 1-2]
C. I. A resist was prepared by the following method using Pigment Red 81: 2 pigment (“FANAL ROSE D4830” manufactured by BASF).
After uniformly stirring and mixing the mixture having the composition shown in Table 1, the mixture was dispersed for 5 hours in an Eiger mill (Eiger Japan “Mini Model M-250 MKII”) using zirconia beads having a diameter of 1 mm, and then a 5 μm filter. Filtration was performed to prepare a pigment dispersion.
Next, the mixture having the composition shown in Table 2 was stirred and mixed to be uniform, filtered through a 2 μm filter, and further filtered through a 0.6 μm filter to obtain an alkali developing type magenta color resist.
As a monomer, trimethylolpropane triacrylate (“NK ester ATMPT” manufactured by Shin-Nakamura Chemical Co., Ltd.), “Irgacure 907” (manufactured by Ciba Geigy) as a photopolymerization initiator, and “EAB-F” as a sensitizer (Hodogaya Chemical Co., Ltd.) As the resin-type dispersant, a phosphate ester dispersant (“Disperbyk-111” manufactured by Big Chemie) was used.

  The pigment dispersions and resists obtained in Examples and Comparative Examples were evaluated for appearance, viscosity, transmittance, and number of particles. Note that the transmittance and the number of particles of the resist obtained in Comparative Example 1 were not evaluated because the resist could not be filtered. Further, the resist obtained in Comparative Example 2 was not evaluated because the hue change with the pigment dispersion was large. The results are shown in Table 3.

Claims (6)

  C. I. Pigment Red 81: 2 pigment, a coloring composition containing an organic solvent having a solubility parameter of 9.0 or less, and a pigment carrier made of a transparent resin, a precursor thereof, or a mixture thereof.   The colored composition according to claim 1, wherein the organic solvent is an acetate solvent.   2. The coloring composition according to claim 1, wherein the pigment carrier comprises a mixture of an acrylic resin and a photopolymerizable monomer or oligomer.   The colored composition according to claim 2 or 3, wherein the acetate solvent is isoamyl acetate.   4. The coloring composition according to claim 2, wherein the acetate solvent is a mixed solvent composed of isoamyl acetate and methoxypropyl acetate. A color filter comprising a magenta color filter segment, a cyan color filter segment, and a yellow color filter segment, wherein the magenta color filter segment is formed using the colored composition according to any one of claims 1 to 5. A color filter characterized by