JP2009035671A - Pigment dispersion, colorant composition, and color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: a pigment dispersion excellent in both of dispersion stability of a pulverized pigment and flowability; a colorant composition; and a color filter satisfying both of high color purity and high contrast ratio. <P>SOLUTION: The pigment dispersion comprises: an azo-metal complex-based pigment and/or an azomethine-metal complex-based pigment; a pigment derivative obtained by introducing sulfonic acid group into the azo-metal complex-based pigment and/or the azomethine-metal complex-based pigment; and a solvent. The pigment dispersion is characterized in that 5-100 wt.% of the pigment derivative is an azo-metal complex-based pigment derivative and/or an azomethine-metal complex-based pigment derivative, having two sulfonic acid groups in one molecule. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a pigment dispersion, a colorant composition, and a color filter used for a liquid crystal display.

  In order to colorize a liquid crystal display, a color filter in which pixels of three colors of R (red), G (green), and B (blue) are arranged in a line shape or a mosaic shape on a transparent substrate is used. . For example, a TFT (thin film transistor) color liquid crystal display that is widely used at present is called a backlight in which a liquid crystal is sealed between a transparent glass substrate on which a color filter is formed and a transparent glass substrate on which a TFT is formed. The light source is made up of. When light emitted from the backlight passes through the liquid crystal panel, an image is displayed by controlling the transmittance by the voltage applied to the liquid crystal. In order to obtain an image with high display quality, that is, bright and high color purity, the pigment used in each pixel is selected to match the light transmission characteristics of the backlight, and two or more pigments are toned at a certain ratio. Often used. For example, the G (green) pixel of the color filter is used by selecting two or more types of green, orange, and yellow pigments. Of these, quinophthalone-based pigments such as PY (Pigment Yellow) 138 are preferably used as toning pigments for G pixels of the color filter because of their high transmittance, and isoforms such as PY185 are preferable because of their strong coloring power. Indoline pigments are preferably used.

  In order to obtain the inherent chromaticity characteristics, transmittance, and contrast ratio of the pigment, it is necessary to disperse the pigment in fine and stable particles. When the dispersion of the pigment is unstable, the pigment aggregates, so that the contrast ratio of the pixel coating film is lowered, and consequently the display quality of the liquid crystal display is lowered. The contrast ratio is also related to the pigment concentration in the pixel. The higher the pigment concentration, the greater the degree of depolarization. Recently, liquid crystal displays are required to have a high color purity, and as a result, the pigment concentration in the pixel becomes high, so that a reduction in contrast ratio is a significant problem.

  In order to stably disperse the pigment in the solvent, a method using an organic pigment sulfonated derivative has been proposed (see Patent Documents 1 to 8). In Patent Document 3, the dispersion of a pigment mixture containing a quinophthalone yellow pigment is stabilized by dispersing a pigment in a solvent by using a quinophthalone derivative having a polar group such as a sulfonic acid group as a dispersant. The value is as high as about 1600. However, since the quinophthalone pigment has a weak coloring power, there is a problem that if the concentration of the quinophthalone pigment in the pixel is increased in order to improve the color purity, the contrast ratio is remarkably lowered. On the other hand, in Patent Document 8, an isoindoline pigment is dispersed and stabilized in a solvent by using an isoindoline pigment derivative having a polar group such as a sulfonic acid group as a dispersant for dispersing the isoindoline pigment. However, since isoindoline pigments are particularly difficult to disperse and stabilize in a miniaturized state, the contrast ratio is as low as about 600.

On the other hand, as a toning pigment for G pixels of a color filter, a method using an azomethine metal complex pigment such as PY129 has been proposed because of its high transmittance and strong coloring power (see Patent Documents 9 to 10). . In Patent Document 9, a pigment mixture containing PY129 is dispersed and stabilized in a solvent by using a polyamic acid. However, since it is difficult to stabilize the dispersion in a fine PY129 state, the contrast ratio of the G pixel coating film is about 1000 even though only 5% by weight of PY129 content in all pigments is added. The value is low. If the density of PY129 in the pixel is increased to improve the color purity of the color filter, there is a problem in that the contrast ratio is remarkably lowered. In Patent Document 10, a pigment mixture containing PY129 is dispersed and stabilized in a solvent by using an acrylic polymer. In this method, a high transmittance of the green pixel is achieved by setting the content of PY129 in the total pigment to 10 to 60% by weight. However, PY129 is difficult to obtain a high contrast ratio because it is difficult to stabilize the dispersion in a miniaturized state.
JP 2002-121418 A JP 2002-121456 A JP 2002-121457 A JP 2002-121458 A JP 2002-121459 A JP 2002-179799 A JP 2003-176424 A JP 2006-146078 A Japanese Patent Laid-Open No. 2003-227921 Japanese Patent Laid-Open No. 10-237326

  The object of the present invention is to provide a pigment dispersion and a colorant composition excellent in dispersion stability and flow characteristics of a refined pigment, and further provide a color filter that achieves both high color purity and a high contrast ratio. The purpose is to do.

That is, the present invention relates to a pigment dispersion containing an azo metal complex pigment and / or an azomethine metal complex pigment, a pigment derivative having a sulfonic acid group introduced into an azo metal complex pigment and / or an azomethine metal complex pigment, and a solvent. A pigment dispersion characterized in that 5 to 100% by weight of the pigment derivative is an azo metal complex pigment and / or an azomethine metal complex pigment derivative having two sulfonic acid groups in one molecule. It is a liquid.
Moreover, this invention is a colorant composition containing this pigment dispersion liquid, and also a color filter formed with this colorant composition.

  The pigment dispersion and the colorant composition of the present invention are produced using an azo metal complex pigment and / or an azomethine metal complex pigment that are finely dispersed and excellent in pigment dispersion stability. The color filter has high color purity and a high contrast ratio, and the liquid crystal display has a wide color reproduction range and excellent visibility.

  The present invention relates to a pigment dispersion containing an azo metal complex pigment and / or an azomethine metal complex pigment, an azo metal complex pigment and / or a pigment derivative having a sulfonic acid group introduced into an azomethine metal complex pigment, and a solvent. 5 to 100% by weight of the pigment derivative must be an azo metal complex pigment and / or an azomethine metal complex pigment metal complex pigment derivative having two sulfonic acid groups in one molecule. is there.

  Usually, a pigment derivative having a sulfonic acid group introduced is strongly bonded to the pigment by intermolecular force and negatively charges the pigment fine particle surface. As a result of intensive studies by the present inventors, a derivative in which two sulfonic acid groups are introduced into an azo metal complex pigment and / or an azomethine metal complex pigment is more azo than a derivative having one sulfonic acid group introduced. It was found that the dispersion stabilizing effect of the metal complex pigment and / or the azomethine metal complex pigment was great. That is, the derivative having two sulfonic acid groups introduced has a higher electrostatic repulsive force between the pigment particles because the pigment particle surface is negatively charged more strongly than the derivative having one introduced, and the pigment dispersion It was found that it greatly contributes to stabilization.

The content of the derivative having two sulfonic acid groups introduced is required to be 5% by weight or more in the total pigment derivative, preferably 10% by weight or more, more preferably 40% by weight or more, and still more preferably It is desired to be 100% by weight. When the content of the derivative having two sulfonic acid groups introduced is less than 5% by weight, the dispersion state of the pigment dispersion becomes unstable, and the color filter obtained from the colorant composition containing the pigment dispersion contains The contrast ratio decreases. In addition, since the number of introduced sulfonic acid groups of 1 is particularly less likely to adversely affect the dispersion state of the pigment, the total amount thereof should be 95% or less, preferably 90% or less. In the pigment dispersion and the colorant composition, the proportion of the derivative having two sulfonic acid groups introduced in the total derivative is determined by negative ion measurement of the copper phthalocyanine sulfonic acid-containing derivative by fast atom bombardment ionization mass spectrometry. It can be calculated from the intensity ratio of the peak of the ion mass to charge ratio corresponding to the number of introduced sulfonic acid groups obtained by negative ion measurement.

  The azo metal complex pigments and / or azomethine metal complex pigments used in the present invention exhibit hues of yellow, green, orange, and red and exhibit various excellent fastness properties including weather resistance. It can be preferably used as a complementary color pigment for R and G pixels in a color filter. Examples of azo metal complex pigments used in the present invention include yellow pigment PY150, green pigments PG8 and PG10, and examples of azomethine metal complex pigments include yellow pigments PY65, PY129, PY153, orange pigment PO68, and red pigment. And pigment PR257. When an azomethine metal complex pigment is used for a G pixel, it is particularly preferable to use PY129 because the pigment has a high coloring power and is excellent in color tone and transmittance.

  The azo metal complex pigment used in the present invention and / or the pigment derivative having a sulfonic acid group introduced into the azomethine metal complex pigment is the same pigment as the azo metal complex pigment and / or azomethine metal complex pigment used. Two types of pigment derivatives, in which a sulfonic acid group is introduced into a pigment having a chemical structure identical to part of the chemical structure of the pigment derivative in which the group is introduced, the azo metal complex pigment and / or the azomethine metal complex pigment to be used These may be used alone or in combination. For example, when an azomethine metal complex yellow pigment PY129 is used as an organic pigment, a sulfonic acid group is introduced into a pigment derivative in which a sulfonic acid group is introduced into PY129, or a yellow pigment PY150 having a part of the same chemical structure as PY129. Each of these pigment derivatives is used alone or in combination. In order to further increase the bonding strength between the pigment and the pigment derivative, it is more preferable to combine the pigment and a pigment derivative having a sulfonic acid group introduced into the pigment itself. In the following description, the two types are collectively referred to as “pigment derivatives having a sulfonic acid group introduced”.

  A pigment derivative having a sulfonic acid group introduced therein is synthesized, for example, by the following method. The organic pigment is added to concentrated sulfuric acid, fuming sulfuric acid, chlorosulfonic acid, or a mixture thereof to perform a sulfonation reaction. The resulting reaction solution is diluted with water and optionally neutralized with a metal alkali aqueous solution or an amine or an aqueous solution thereof. The suspension thus obtained is filtered, washed with an aqueous washing solution, and dried.

  When neutralization is performed in the above synthesis process, a metal alkali aqueous solution or an amine or an aqueous solution thereof is used, but an amine or an aqueous solution thereof is preferably used. If a pigment dispersion for color filters, and thus a colorant composition using the same, contains a metal alkali, it may remain in the color filter pixels and elute into the liquid crystal, resulting in display defects due to liquid crystal drive inhibition. Because there is.

  As the aqueous amine solution used for neutralization, an aqueous solution of ammonia, monoethanolamine, triethanolamine, tetramethylammonium hydroxide, or the like can be used. In the present invention, various amine aqueous solutions can be used without being particularly limited to these, but the use of ammonia is preferred because of its ease of volatilization.

In the pigment derivative introduced with the sulfonic acid group used in the present invention, a large amount of sulfate ions usually remain from the reaction solution after the sulfonation reaction. In order to remove sulfate ions from the pigment derivative, a technique of dialysis or ion exchange can be mentioned. In particular, dialysis is effective without increasing the viscosity of the slurry by removing water and sulfate ions through a dialysis membrane from the slurry of pigment derivative, water and sulfate ions, and adding the same amount of ion-exchanged water as the amount removed. It is possible to remove sulfate ions. In order to efficiently remove sulfate ions, it is preferable to use a hollow fiber membrane having a large dialysis effective area. As a material of the hollow fiber membrane, polysulfone, polymethyl methacrylate, polyacrylonitrile, or the like can be used.
The sulfate ion concentration in the pigment dispersion of the present invention is 100 ppm or less, preferably 50 ppm or less, more preferably 20 ppm or less. If the sulfate ion concentration is higher than 50 ppm, the dispersion state of the pigment dispersion may become unstable. The lower limit of the sulfate ion concentration is preferably 0.1 ppm. For example, if the sulfate ion concentration is to be made smaller than 0.1 ppm by dialysis, the number of times dialysis is repeated greatly increases and the possibility of clogging of the dialysis membrane increases.

  In the present invention, when PY129 is used as the azomethine metal complex pigment, the mixing ratio of PY129 and the pigment derivative having a sulfonic acid group introduced into PY129 is a weight ratio, preferably 85:15 to 99: 1, more preferably It is desirable to be in the range of 90:10 to 98: 2. If the amount of the pigment derivative is too small, the effect of stabilizing the pigment dispersion is not exhibited. Conversely, if the amount of the pigmented derivative is too large, the luminance may decrease.

  The solvent used in the pigment dispersion of the present invention contains an organic solvent as a solvent component in an amount of 60% by weight or more in all the solvents. 80% by weight or more is preferably an organic solvent, more preferably 95% by weight or more. The organic solvent that can be used is not particularly limited as long as it is a general organic solvent. For example, methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, (Poly) alkylene glycol ether solvents such as propylene glycol monoethyl ether and diethylene glycol monomethyl ether, or propylene glycol monoethyl ether acetate, ethyl acetoacetate, methyl-3-methoxypropionate, 3-methyl-3-methoxybutyl Aliphatic esters such as acetate, or aliphatic alcohols such as ethanol, 3-methyl-3-methoxybutanol, cyclopentanone, Ketones such as cyclohexanone can be employed. In this invention, you may use said solvent individually or in mixture of 2 or more types. Mixing with a solvent other than the above is also preferably used.

  The pigment dispersion of the present invention contains an azo metal complex pigment and / or an azomethine metal complex pigment, a pigment derivative having a sulfonic acid group introduced therein, and an organic solvent as essential components. , Pigments other than azo metal complex pigments and / or azomethine metal complex pigments for toning, pigment derivatives other than azo metal complex pigments and / or azomethine metal complex pigments for improving dispersion stability, polymers A dispersant, a resin, or the like may be included. As the resin, it is particularly preferable to use an acrylic resin or a polyimide resin. Therefore, it is preferable to use a solvent that dissolves these resins as the solvent. Specifically, in particular when the resin is a polyimide resin, in addition to the above, a solvent for dissolving the precursor polyamic acid, that is, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N Amide polar solvents such as, N-dimethylformamide, lactones such as β-propiolactone, γ-butyrolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, and ε-caprolactone can be preferably used.

  The pigment other than the azo metal complex pigment and / or the azomethine metal complex pigment that can be used in the present invention is not particularly limited, but the azo metal complex pigment and / or the azomethine metal complex pigment is R of the color filter. In view of the fact that they are often used as complementary color pigments for G pixels, they are red and orange pigments that are main pigments for R pixels, green pigments that are main pigments for G pixels, or complementary colors for R and G pixels. It is preferable to use other yellow pigments.

  Examples of red pigments include Pigment Red 9, 48, 97, 122, 123, 144, 149, 166, 168, 177, 179, 180, 192, 209, 215, 216, 217, 220, 223, 224, and 226. 227, 228, 240, 254, etc. can be used.

  Examples of orange pigments include pigment oranges 13, 36, 38, 43, 51, 55, 59, 61, 64, 65, 71, and the like.

Examples of green pigments include pigment green 7, 10, 36, and the like.
Examples of yellow pigments include Pigment Yellow-12, 13, 17, 20, 24, 83, 86, 93, 95, 109, 110, 117, 125, 137, 138, 139, 147, 148, 150, 154, 166, 168, 185, etc. can be used. In addition, the said pigment may use what was surface-treated, such as a rosin process, an acidic group process, a basic process, and a pigment derivative process, as needed.

  In the present invention, azo metal complex pigments and / or azomethine metal complex pigments and other pigments can be used alone or in combination of two or more. In particular, when used for G pixels, a color filter having high color purity, high contrast ratio, and high luminance can be obtained. Therefore, there is a formulation using PY129 as an azomethine metal complex pigment and PG7 and / or PG36 as a green pigment. preferable. When PG7, PG36, and PY129 are used, the mixing ratio of the pigment is a weight ratio, preferably PG7: PG36: PY129 = 20: 20: 60 to 45:45:10, more preferably 25:25:50 to 40 : 40:20. The mixing ratio is appropriately adjusted depending on the required color tone.

  Further, in the present invention, in order to stabilize the dispersion of the pigment, in addition to the pigment derivative having a sulfonic acid group introduced, a low molecular dispersant such as an intermediate of the used pigment, a derivative, an intermediate of the dye, or a derivative is used. This is also preferably done.

  In the pigment dispersion of the present invention, a polymer dispersant can be added as another component. By adding a polymer dispersant, further improvement in dispersion stability can be expected. The addition of the polymer dispersant is particularly effective when the pigment dispersion and the colorant composition of the present invention are acrylic resins. The polymer dispersant is used at the time of pigment dispersion or after the pigment dispersion step. As the polymer dispersant that can be used, those having a basic group in the structure thereof are preferable. Examples of commercially available products include “Solsperse” (Avicia), “EFKA” (Efka), “Ajisper”. (Ajinomoto Fine Techno Co., Ltd.), “BYK” (Bic Chemie Co., Ltd.) and the like can be preferably used. "Solsparse" 24000, "EFKA" 4300, 4330, 4340, "Ajisper" PB821, PB822, "BYK" 161-163, 2000, 2001 are preferred because the dispersion stabilization effect is high, especially block structure “BYK” 2000 and 2001, which are acrylic dispersants having a high molecular weight, are preferable because of their excellent adsorption ability to pigments.

  The addition amount of the polymer dispersant used in the present invention is not particularly limited, but is preferably 2 to 100 parts by weight, more preferably 10 to 50 parts by weight with respect to 100 parts by weight of the pigment. is there. If the addition amount of the polymer dispersant is less than 2 parts by weight, good pigment dispersion stability cannot be obtained, and if it is more than 100 parts by weight, the developability may be poor.

It is also preferable to add a resin other than the polymer dispersant to the pigment dispersion of the present invention in that the dispersion stability can be further improved. Although there is no limitation in particular as a kind of resin, it is preferable that it is the same kind as resin used for the coloring agent composition mentioned later from a compatible point, and the acrylic resin and polyamic acid resin mentioned later can be used preferably.
The concentration of the pigment in the pigment dispersion of the present invention is preferably in the range of 4 to 90 parts by weight, more preferably 5 to 18 parts by weight when the entire pigment dispersion is 100 parts by weight.

  The pigment dispersion method in the pigment dispersion of the present invention is not particularly limited, and various methods such as a sand mill, a ball mill, a bead mill, a three roll mill, and a high speed impact mill are employed. In dispersion using media, zirconia beads, alumina beads, glass beads, and the like can be used.

The dispersion stability of the pigment dispersion of the present invention can be evaluated by measuring the Casson yield value of the pigment dispersion. The smaller the Casson yield value, the less agglomeration of particles in the particle dispersion. In the present invention, the Casson yield value of the pigment dispersion is preferably 1 × 10 ⁻³ Pa or less, more preferably 1 × 10 ⁻⁴ Pa or less.

  Further, the viscosity of the pigment dispersion is preferably 300 mPa · s or less, more preferably 100 mPa · s or less. When the viscosity of the pigment dispersion is greater than 300 mPa · s, the viscosity of the colorant composition containing the pigment dispersion also increases, and it may be difficult to uniformly apply the colorant composition. The yield value and viscosity of the pigment dispersion can be controlled by optimizing the number of sulfonic acid groups introduced into the pigment derivative.

Next, the colorant composition of the present invention will be described.
The resin of the colorant composition of the present invention is not particularly limited, and resins usually used for color filters, that is, resins such as acrylic, epoxy, or polyamic acid can be preferably used. Depending on the resin used, it can be non-photosensitive or photosensitive, and can be appropriately selected according to the color filter manufacturing process.

  Hereinafter, the case where polyamic acid is used as a typical example of a resin used for a non-photosensitive colorant composition and an acrylic resin is used as a typical example of a resin used for a photosensitive colorant composition will be described in detail. .

  A polyamic acid can be obtained by reacting a tetracarboxylic dianhydride and a diamine. In the synthesis of the polyamic acid in the present invention, for example, an aliphatic or alicyclic one can be used as the tetracarboxylic dianhydride, and specific examples thereof include 1,2,3,4. -Cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,3,5-cyclopentanetetracarboxylic dianhydride, 1,2,4,5 -Bicyclohexene tetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo -3-furanyl) -naphtho [1,2-C] furan-1,3-dione and the like. Further, when an aromatic material is used, a polyamic acid that can be converted into a film having good heat resistance can be obtained. As a specific example, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid Dianhydride, pyromellitic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride, 4,4 ′ -Oxydiphthalic anhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 3,3 ", 4,4"- Examples include paraterphenyl tetracarboxylic dianhydride and 3,3 ″, 4,4 ″ -metaterphenyl tetracarboxylic dianhydride. Further, when a fluorine-based tetracarboxylic dianhydride is used, a polyamic acid that can be converted into a film having good transparency in the short wavelength region can be obtained. As a specific example, 4,4′- (Hexafluoroisopropylidene) diphthalic anhydride and the like. In the present invention, tetracarboxylic dianhydrides can be used alone or in combination of two or more without being limited thereto.

  In the synthesis of the polyamic acid in the present invention, for example, an aliphatic or alicyclic diamine can be used as the diamine, and specific examples thereof include ethylenediamine, 1,3-diaminocyclohexane, 1 4,4-diaminocyclohexane, 4,4′-diamino-3,3′-dimethyldicyclohexylmethane, 4,4′-diamino-3,3′-dimethyldicyclohexyl, and the like. In addition, when an aromatic diamine is used, a polyamic acid that can be converted into a film having good heat resistance can be obtained. Specific examples thereof include 4,4′-diaminodiphenyl ether and 3,4′-diamino. Diphenyl ether, 4,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfide, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2,6-diaminotoluene, benzidine, 3,3′-dimethylbenzidine, 3,3′-dimethoxybenzidine, o-tolidine, 4, 4 "-diaminoterphenyl, 1,5-diaminonaphthalene, 3,3 ' Dimethyl-4,4′-diaminodiphenylmethane, 4,4′-bis (4-aminophenoxy) biphenyl, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, bis [4- (4-amino Phenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, etc. When a fluorinated diamine is used, A polyamic acid that can be converted into a film having good transparency in the short wavelength region can be obtained. Specific examples thereof include 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane and the like. Is mentioned.

  Moreover, when siloxane diamine is used as a part of diamine, the adhesiveness with an inorganic substrate can be made favorable. Siloxane diamine is usually used in an amount of 1 to 20 mol% in the total diamine. If the amount of siloxane diamine is too small, the effect of improving adhesiveness is not exhibited, and if it is too large, the heat resistance tends to decrease. Specific examples of the siloxane diamine include bis-3- (aminopropyl) tetramethylsiloxane. The present invention is not limited to this, and one or more diamines are used.

  In general, the polyamic acid is synthesized by mixing and reacting a tetracarboxylic dianhydride and a diamine in a polar organic solvent. At this time, the polymerization degree of the polyamic acid obtained can be adjusted by the mixing ratio of diamine and tetracarboxylic dianhydride.

  The content of the polyamic acid in the colorant composition of the present invention is preferably 40 to 90% by mass, more preferably 45 to 80% by mass, and still more preferably 48 to 75% by mass with respect to the entire solid content. When the content of polyamic acid is less than 40% by mass, the solubility in a developer is lowered, and a problem may occur in patterning performance. If the polyamic acid content exceeds 90%, the pigment content will be relatively low, so the film thickness for obtaining a predetermined chromaticity will be too large, making it difficult to apply, or a color filter. A step on the surface becomes large, and display defects may occur.

  Next, the number of repeating structural units of the polyamic acid used in the present invention will be described. Since the mechanical properties of the polyimide film are better as the molecular weight is larger, it is desirable that the molecular weight of the polyamic acid that is the polyimide precursor is also larger. On the other hand, when pattern processing is performed on the polyimide precursor film by wet etching, if the molecular weight of the polyamic acid is too large, there is a problem that the time required for development becomes too long. Therefore, the preferable range of the number of repeating structural units is 15 to 1000, more preferably 18 to 400, and still more preferably 20 to 100. In addition, since the molecular weight of polyamic acid generally varies, the preferable range of the number of repeating structural units here is 50 mol% or more, preferably 70 mol% of the structural units of all polyamic acids in this range. As mentioned above, it means that 90 mol% or more is contained.

  An acrylic resin will be described as an example of the resin used in the photosensitive colorant composition. The acrylic resin generally has a structure containing at least an acrylic polymer, a polyfunctional monomer or oligomer, and a photopolymerization initiator in order to provide photosensitivity.

  The acrylic polymer that can be used is not particularly limited, but a copolymer of an unsaturated carboxylic acid and an ethylenically unsaturated compound can be preferably used. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides.

  These may be used alone or in combination with other copolymerizable ethylenically unsaturated compounds. Specific examples of the copolymerizable ethylenically unsaturated compound include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, isopropyl acrylate, n-propyl methacrylate, and methacrylic acid. Isopropyl, n-butyl acrylate, n-butyl methacrylate, sec-butyl acrylate, sec-butyl methacrylate, iso-butyl acrylate, iso-butyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, N-pentyl acrylate, n-pentyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, benzyl acrylate, benzyl methacrylate, and other unsaturated carboxylic acid alkyl esters, styrene, p-methyls Rene, aromatic vinyl compounds such as o-methylstyrene, m-methylstyrene and α-methylstyrene, unsaturated carboxylic acid aminoalkyl esters such as aminoethyl acrylate, unsaturated carboxylic acid glycidyl esters such as glycidyl acrylate and glycidyl methacrylate, Carboxylic acid vinyl esters such as vinyl acetate and vinyl propionate, vinyl cyanide compounds such as acrylonitrile, methacrylonitrile, and α-chloroacrylonitrile, aliphatic conjugated dienes such as 1,3-butadiene and isoprene, acryloyl groups at the terminals, Alternatively, macromonomers such as polystyrene, polymethyl acrylate, polymethyl methacrylate, polybutyl acrylate, polybutyl methacrylate, and polysilicone having a methacryloyl group And the like, but is not limited to these.

  In addition, it is preferable to use an acrylic polymer having an ethylenically unsaturated group added to the side chain, since the sensitivity during processing is improved. Examples of the ethylenically unsaturated group include a vinyl group, an allyl group, an acrylic group, and a methacryl group. As a method of adding such a side chain to an acrylic copolymer, when the acrylic copolymer has a carboxyl group or a hydroxyl group, an ethylenically unsaturated compound having a glycidyl group, acrylic acid or methacrylic acid is used. A method of addition reaction of chloride is common. In addition, a compound having an ethylenically unsaturated group can be added using isocyanate. Examples of the ethylenically unsaturated compound having glycidyl group and acrylic acid or methacrylic acid chloride include glycidyl acrylate, glycidyl methacrylate, glycidyl α-ethyl acrylate, crotonyl glycidyl ether, glycidyl crotonic acid, and glycidyl isocrotonate. Examples include ether, acrylic acid chloride, and methacrylic acid chloride.

  The content of the acrylic polymer in the colorant composition of the present invention is preferably 10 to 50% by mass, more preferably 12 to 40% by mass, and further preferably 15 to 30% by mass with respect to the entire solid content. . When the content of the acrylic polymer is less than 10% by mass, the solubility in the developer is lowered, and there may be a problem in patterning performance. If the content of acrylic resin is more than 50% by mass, the content of other components such as polyfunctional monomers and photoinitiators will be relatively small, so sufficient sensitivity will not be obtained and the required exposure will be large. In some cases, it may cause a tact-over, or may be too soluble in the developer, and may be peeled off during development.

  Examples of the polyfunctional monomer include bisphenol A diglycidyl ether (meth) acrylate, poly (meth) acrylate carbamate, modified bisphenol A epoxy (meth) acrylate, adipic acid 1,6-hexanediol (meth) acrylate, anhydrous Phthalic acid propylene oxide (meth) acrylic acid ester, trimellitic acid diethylene glycol (meth) acrylic acid ester, rosin modified epoxy di (meth) acrylate, alkyd modified (meth) acrylate, tripropylene glycol di (meth) acrylate, 1,6- Hexanediol di (meth) acrylate, bisphenol A diglycidyl ether di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol (Meth) acrylate, triacrylformal, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate. These can be used alone or in combination. Also, ethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, hydroxyethyl (meth) acrylate, n-butyl methacrylate, glycidyl methacrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, isobornyl (meth) acrylate, etc. A monofunctional monomer can also be used in combination, and a mixture of two or more of these or a mixture with other compounds is used. By selecting and combining these polyfunctional and monofunctional monomers and oligomers composed of these monomers, it is possible to control the sensitivity and processability characteristics of the paste. In particular, in order to increase the hardness, it is preferable to use a methacrylate compound rather than an acrylate compound, and in order to increase sensitivity, it is preferable to use a compound having three or more functional groups. Melamines and guanamines can also be preferably used in place of the acrylic monomers.

  The content of the polyfunctional monomer in the colorant composition of the present invention is preferably 10 to 50% by mass, more preferably 12 to 40% by mass, and still more preferably 15 to 30% by mass with respect to the entire solid content. . When the content of the acrylic resin is less than 10% by mass, the film may not be sufficiently cured with respect to light, and shape abnormality such as pattern swelling during development may occur. If the content of the polyfunctional monomer exceeds 50% by mass, the content of other components such as an acrylic resin and a photoinitiator is relatively reduced, so that sufficient sensitivity cannot be obtained and the necessary exposure amount is low. In some cases, it becomes too large, resulting in a tact-over, or the solubility in the developer is too great, and peeling during development may occur.

  There are no particular limitations on the photopolymerization initiator, and known ones can be used, such as benzophenone, N, N′-tetraethyl-4,4′-diaminobenzophenone, 4-methoxy-4′-dimethylaminobenzophenone, 2 , 2-diethoxyacetophenone, benzoin, benzoin methyl ether, benzoin isobutyl ether, benzyldimethyl ketal, α-hydroxyisobutylphenone, thioxanthone, 2-chlorothioxanthone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (Methylthio) phenyl] -2-morpholino-1-propane, t-butylanthraquinone, 1-chloroanthraquinone, 2,3-dichloroanthraquinone, 3-chloro-2-methylanthraquinone, 2-ethylanthraquinone, 1, 4-naphthoquinone, 9,10-phenanthraquinone, 1,2-benzoanthraquinone, 1,4-dimethylanthraquinone, 2-phenylanthraquinone, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, etc. Can be given. Further, inorganic photopolymerization initiators such as other acetophenone compounds, imidazole compounds, benzophenone compounds, thioxanthone compounds, phosphorus compounds, triazine compounds, and titanates can also be preferably used. Further, it is preferable to add a sensitizing aid such as p-dimethylaminobenzoic acid ester because the sensitivity can be further improved. Moreover, these photoinitiators can also be used in combination of 2 or more types.

  Although there is no limitation in particular as the addition amount of a photoinitiator, Preferably it is 1-30 mass% with respect to a coloring agent composition total solid, More preferably, it is 5-25 mass%, More preferably, it is 10-20. % By mass.

  In the colorant composition of the present invention, the solid content concentration of the resin component and the pigment is 2 to 30% by mass, preferably 3 to 25% by mass, and more preferably 5 from the viewpoints of coating properties and drying properties. Used in the range of ˜20% by mass.

  As the solvent in the colorant composition of the present invention, a solvent that dissolves the resin to be used can be preferably used. Examples of the solvent for dissolving polyamic acid include amide polar solvents such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, β-propiolactone, γ-butyrolactone, γ- Examples include lactones such as valerolactone, δ-valerolactone, γ-caprolactone, and ε-caprolactone. In the case of acrylic resins, in addition to these, for example, ethylene glycol or propylene glycol derivatives such as methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol, propylene glycol monoethyl ether, or propylene glycol monoethyl ether Aliphatic esters such as acetate, ethyl acetoacetate, methyl-3-methoxypropionate, 3-methyl-3-methoxybutylacetate, or aliphatic alcohols such as ethanol, 3-methyl-3-methoxybutanol, It is also possible to use ketones such as cyclopentanone and cyclohexanone.

  Moreover, as a solvent used for the coloring agent composition of this invention, it may be individual or may use the mixed solvent which combined 2 or more types of solvents suitably. In the case of a mixed solvent, it is possible to use a poor solvent for the resin to be used as a secondary solvent. As a preferable solvent system, for example, when polyamic acid is used as a resin, a combination of γ-butyrolactone and 3-methyl-3-methoxybutanol is preferable. Although there is no restriction | limiting in particular in the coloring agent composition of this invention, It is preferable to use the above organic solvents as a main component like the case of the said pigment dispersion liquid. Here, the main component means that 50% by weight or more, more preferably 80% by weight or more, and still more preferably 95% by weight or more of the total solvent is an organic solvent instead of water.

  A surfactant may be added to the colorant composition of the present invention for the purpose of improving the coating property and the drying property of the colored film. The addition amount of the surfactant is usually 0.001 to 10% by mass, preferably 0.01 to 1% by mass of the pigment. If the addition amount is too small, the effect of improving the coatability and the drying property of the colored coating film is small, and if it is too large, the physical properties of the coating film may be poor. Specific examples of the surfactant include anionic surfactants such as ammonium lauryl sulfate and polyoxyethylene alkyl ether sulfate triethanolamine, cationic surfactants such as stearylamine acetate and lauryltrimethylammonium chloride, lauryldimethylamine oxide, Amphoteric surfactants such as lauryl carboxymethyl hydroxyethyl imidazolium betaine, nonionic surfactants such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, sorbitan monostearate, and silicones based on polydimethylsiloxane Surfactant etc. are mentioned. In the present invention, the surfactant is not limited to these, and one or more surfactants can be used. In addition to the surfactant, an adhesion improver, a curing accelerator, and the like can be added.

Hereinafter, a method for producing a color filter using the colorant composition of the present invention will be described.
The color filter usually has a structure in which RGB three-color patterns are formed on a transparent substrate on which a black matrix (BM) is formed.

  As the BM, a known material, that is, Cr, Cr oxynitride, or a resin BM in which a light shielding material such as carbon black or titanium black is dispersed in a resin can be preferably used.

  The red, green, and blue colorant compositions for forming RGB pixels are not particularly limited. For example, as in the colorant composition of the present invention described above, a main pigment and a secondary colorant are added in a resin and a solvent. It is produced by toning with a pigment system composed of a pigment. Here, the colorant composition containing the azo metal complex pigment and / or azomethine metal complex pigment of the present invention and a pigment derivative having a sulfonic acid group introduced is mainly a red and / or green colorant composition, More preferably, it is applied as a green colorant composition.

  As a method of applying the colorant composition on the substrate, a method of applying to the substrate by a spin coater, bar coater, blade coater, roll coater, die coater, screen printing method, etc., a method of immersing the substrate in a solution, a solution Various methods, such as spraying on the substrate, can be used. As the substrate, a transparent substrate such as soda glass, non-alkali glass, borosilicate glass, or quartz glass, or a semiconductor substrate such as silicon or gallium arsenide is usually used, but is not particularly limited thereto. In addition, when applying a colorant composition on a substrate, if the substrate surface is treated with an adhesion aid such as a silane coupling agent, an aluminum chelating agent, or a titanium chelating agent, the adhesion between the colored coating and the substrate is improved. Can be done as needed.

  After coating the colorant composition on the transparent substrate by the method as described above, a coating film of the colorant composition is formed by air drying, heat drying, vacuum drying or the like. In the case of heat-drying, it is preferable to use an oven, a hot plate, etc., and carry out at 50-180 degreeC for 1 minute-3 hours. Next, when the colorant composition is non-photosensitive, a photoresist is applied on the coating film to form a photoresist film. In the case of photosensitivity, a photoresist is not necessary, but an oxygen blocking film may be formed if necessary. Subsequently, a mask is placed on the coating and irradiated with ultraviolet rays using an exposure apparatus. Next, the color paste coating film is etched with an alkali developer. When there is a photoresist film or an oxygen barrier film, the development or etching of these is performed at the same time, and then these are removed with a stripping solution.

  The alkaline substance used in the alkaline developer is not particularly limited. For example, inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, ethylamine, n -Primary amines such as propylamine, secondary amines such as diethylamine and di-n-propylamine, tertiary amines such as triethylamine and methyldiethylamine, tetraalkylammonium hydroxy such as tetramethylammonium hydroxide (TMAH) Quaternary ammonium salts such as choline, triethanolamine, diethanolamine, monoethanolamine, dimethylaminoethanol, diethylaminoethanol, pyrrole, piperidine, 1,8-dia Bicyclo [5,4,0] -7-undecene, 1,5-diazabicyclo [4,3,0] -5-nonane, organic alkalis such as cyclic amines such as morpholine. Depending on development conditions and coating film conditions, the inorganic alkali is preferably potassium hydroxide or sodium carbonate, and the organic alkali is a hydroxyl-containing organic amine such as a tetraalkylammonium hydroxide or an alcoholamine. More specifically, diethylaminoethanol, dimethylaminoethanol, and TMAH are particularly preferable because of excellent permeability to the etching film. Further, a water-soluble organic solvent such as ethanol, γ-butyrolactone, dimethylformamide, N-methyl-2-pyrrolidone may be appropriately added to the above alkaline developer.

  The resulting coating pattern of the colorant composition becomes a color filter patterned by heat treatment thereafter. The heat treatment is usually performed in air, in a nitrogen atmosphere, or in a vacuum at a temperature of 150 to 350 ° C., preferably 180 to 300 ° C., for 0.5 to 5 hours continuously or stepwise. Done. By this heating step, the polyimide precursor is converted into polyimide, and the photosensitive acrylic resin is cured.

  When the patterning process as described above is sequentially performed for each color such as R, G, and B, a color filter for a liquid crystal display device can be produced. Here, the patterning order of each color is not limited. In the present invention, in a color filter in which pixels of one color or a plurality of colors are provided in a pattern, the pixels have a colored layer, and at least one color of the colored layers is the above azo metal complex pigment and / or Alternatively, a color filter having a high color purity and a high contrast ratio can be obtained by forming with a colorant composition containing an azomethine metal complex pigment and a pigment derivative having a sulfonic acid group introduced.

  The contrast ratio of the color filter obtained from the colorant composition of the present invention is desired to be 1000 or more, more preferably 1500 or more, and still more preferably 2000 or more. The larger the contrast ratio of the color filter, the better the visibility of the liquid crystal display panel. The contrast ratio can be improved by optimizing the number of sulfonic acid groups introduced into the pigment derivative into which the sulfonic acid group has been introduced, the mixing ratio between the pigment and the pigment derivative into which the sulfonic acid group has been introduced, and the like.

  When the pixel obtained from the colorant composition of the present invention is a G pixel, chromaticity coordinates (x, y) are x = 0.2 to 0.35, y = 0.5 to 0.72, preferably It is preferable that x = 0.21 to 0.34 and y = 0.55 to 0.71. By setting the chromaticity coordinates of the G pixel to the above range, the color reproduction range of the liquid crystal display panel can be sufficiently expanded. The chromaticity coordinates (x, y) can be set to the above range, for example, by setting the composition ratio of the pigment to a range of PG7: PG36: PY129 = 20: 20: 60 to 45:45:10.

  Although there is no restriction | limiting in particular in the film thickness of the color filter obtained from the coloring agent composition of this invention, Preferably it is 0.1-10 micrometers, More preferably, it is good that it is 0.5-5 micrometers. If the film thickness is too small, the light absorption becomes too small and the optical characteristics as a color filter are not satisfied. On the other hand, when the film thickness is too large, problems such as excessive light absorption may occur, and the optical characteristics as a color filter may not be satisfied. As optical characteristics, there is usually a desired chromaticity depending on the application, so that a colored film is prepared by adjusting the pigment composition and film thickness to match this.

  Hereinafter, although this invention is demonstrated in more detail using a preferable embodiment, the efficacy of this invention is not restrict | limited at all by the embodiment used.

  The pigment derivatives, pigment dispersions, colorant compositions, and color filters in the examples were evaluated by the following methods.

<Measurement method>
The number of sulfonic acid groups introduced into the pigment derivative m-nitrobenzyl alcohol was used as a matrix, and negative ion measurement of the pigment derivative was performed using a fast atom bombardment ionization mass spectrometer (JEOL Ltd. JMS-SX102A). . The measurement is performed in the range of 10 to 2000 in terms of the ratio (m / z) of the mass (m) and charge (z) of ions generated by ionization, and the number of introduced sulfonic acid groups of the pigment derivative from the obtained m / z strength. Asked.

Viscosity of Pigment Dispersion The viscosity of the pigment dispersion at 25 ° C. was measured using a conical plate viscometer (RE100L manufactured by Toki Sangyo Co., Ltd.).

Yield Value of Pigment Dispersion Using a cone-plate viscometer (RE100L manufactured by Toki Sangyo Co., Ltd.), the viscosity at three different shear rates was measured, and the yield value was determined by using the Casson equation. The dispersion stability of the pigment dispersion was evaluated from the obtained yield value.

Contrast ratio of the color filter formed from the colorant composition A coating film formed by coating the colorant composition on a glass substrate is prepared, and the polarizer and the analyzer are placed so that the film surface falls within the entire measurement area. By measuring the ratio (I1 / I2) of the light transmittance (I1) when the polarizer and the analyzer are parallel to each other and the light transmittance (I2) when the polarizer and the analyzer are orthogonal The contrast ratio was calculated. A polarizing film “NPF-G1220DUN” manufactured by Nitto Denko Corporation was used for the polarizer and the analyzer. “FL8A-EX / 70” manufactured by Meidaku System, which is a backlight unit using a hot cathode tube as a light source, was used, and “BM-5A” manufactured by Topcon Corporation was used as a color luminance meter.

Chromaticity of a color filter formed from the colorant composition The chromaticity coordinates (x, y) and luminance (Y) in the C light source XYZ color system of the colorant composition coating film are manufactured by Otsuka Electronics Co., Ltd. It measured using microspectrophotometer "MCPD-2000".

The film thickness of the color filter formed from the colorant composition The film thickness of the colorant composition coating film was measured using a surface step meter “Surfcom 1400D” manufactured by Tokyo Seimitsu Co., Ltd.

Example 1
Synthesis of Pigment Derivative 60 g of PY129 (“Irgazine Yellow” (trade name) 5GLT manufactured by Ciba Specialty Chemicals Co., Ltd.) was added to 780 g of fuming sulfuric acid (28 wt% SO ₃ ) with stirring under ice cooling. The temperature of the solution during the reaction was 0 to 5 ° C. After stirring for 3 hours, the mixture was poured into 1500 g of ice water. After standing for 30 minutes, the resulting suspension was filtered, and the resulting product was washed with 300 ml of pure water. The product was put into 2000 ml of pure water, an aqueous ammonia solution was added until the pH reached 7 or more with an aqueous ammonia solution, neutralized, and then filtered. The obtained wet crystals were washed with pure water and then dried at 80 ° C. The operations obtained by drying, washing with pure water, filtering and drying were repeated 10 times to obtain 62 g of PY129 sulfonic acid group-containing derivative YS-A.
Next, YS-A and ion-exchanged water were mixed to prepare a slurry containing sulfate ions. The prepared slurry was dialyzed using a PMMA dialysis module ("Filtizer" (trade name) B3-20A manufactured by Toray Industries, Inc.) to obtain purified PY129 derivative YS-Ad. When the number of sulfonic acid groups introduced into YS-Ad was measured by the method described above, only a peak at m / z = 483 indicating that two sulfonic acid groups were introduced into PY129 was observed.

Synthesis of polyamic acid 95.1 g of 4,4′-diaminodiphenyl ether and 6.2 g of bis (3-aminopropyl) tetramethyldisiloxane were charged with 525 g of γ-butyrolactone and 220 g of N-methyl-2-pyrrolidone. 144.1 g of 4,4′-biphenyltetracarboxylic dianhydride was added and reacted at 70 ° C. for 3 hours, then 3.0 g of phthalic anhydride was added, and further reacted at 70 ° C. for 2 hours. A weight% polyamic acid solution (PAA-1) was obtained.

Synthesis of Polymer Dispersant 161.3 g of 4,4′-diaminobenzanilide, 176.7 g of 3,3′-diaminodiphenylsulfone, and 18.6 g of bis (3-aminopropyl) tetramethyldisiloxane, 2667 g of γ-butyrolactone, Charged together with 527 g of N-methyl-2-pyrrolidone, 439.1 g of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was added, reacted at 70 ° C. for 3 hours, and then phthalic anhydride. 2 g was added and further reacted at 70 ° C. for 2 hours to obtain a 20 wt% polyamic acid solution (PD-1).

Preparation of Pigment Dispersion PG7 25.3 g (38% by weight of the whole pigment), PG36 25.3 g (38% by weight of the whole pigment), PY129 15.5 g (23.3% by weight of the whole pigment), PY129 derivative YS- 0.5 g of Ad (0.7% by weight of the entire pigment), 49.3 g of polymer dispersant (PD-1) and 884.2 g of γ-butyrolactone were mixed and stirred with a homodisper to prepare a slurry. The beaker containing the slurry was connected with a circulation type bead mill disperser ("Dynomill" KDL-A manufactured by Willy et Bacofen) and a tube, and zirconia beads having a diameter of 0.3 mm were used as a medium at 3200 rpm for 3 hours. Dispersion treatment was performed to obtain a pigment dispersion. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives was 100% by weight, and the weight ratio of PY129 to PY129 sulfonated derivative was 97: 3.

Preparation of Colorant Composition In 587.3 g of the pigment dispersion prepared in D, 131.56 g of the polymer solution (PAA-1) was added 151.43 g of γ-butyrolactone and 129.64 g of 3-methoxy-3-methyl-1-butanol. The diluted solution was added and mixed, and a surfactant “BYK361” manufactured by bic chemie was added to a total solid content of 1000 ppm to obtain a green colorant composition. The pigment / polymer ratio (weight ratio) of this green colorant composition is 50/50.

Production of Color Filter The green colorant composition was applied onto a transparent glass substrate using a spinner, and then heat-treated in a hot air oven at 120 ° C. for 10 minutes to obtain a green colorant composition coating film. In addition, application | coating of the red colorant composition adjusted the spinner rotation speed so that the chromaticity of the pattern might become y = 0.675 with a C light source. Subsequently, a positive photoresist (“OFPR-800” manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied thereon and dried at 90 ° C. for 10 minutes. Using a UV exposure machine “PLA-501F” manufactured by Canon Inc., exposure was performed at 60 mJ / cm 2 (ultraviolet intensity of 365 nm) through a chrome photomask. After the exposure, the film was immersed in a developer composed of a 2.25% aqueous solution of tetramethylammonium hydroxide, and development of the photoresist and etching of the colored coating film of the polyimide precursor were simultaneously performed. The photoresist layer that became unnecessary after etching was stripped with methyl cellosolve acetate. Furthermore, the colored coating film of the polyimide precursor was heat-treated at 270 ° C. for 30 minutes to convert to polyimide. A green color filter was formed as described above.

Comparative Example 1
Sulfonation reaction and purification were performed in the same manner as in Example 1 except that 60 g of PY129 was put into 780 g of concentrated sulfuric acid (98 wt% H ₂ SO ₄ ) to obtain 58 g of PY129 sulfonated derivative YS-Bd. . When the number of introduced sulfonic acid groups in YS-Bd was measured by the method described above, only a peak at m / z = 403 indicating that one sulfonic acid group was introduced into PY129 was observed.

  Next, a green pigment dispersion, a colorant composition, and a color filter were prepared in the same manner as in Example 1 except that YS-Bd was used as the pigment derivative. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives was 0% by weight, and the weight ratio of PY129 and PY129 sulfonated derivative was 97: 3.

Example 2
A pigment dispersion, a green colorant composition, and a green color filter were produced in the same manner as in Example 1 except that 0.25 g of YS-Ad and 0.25 g of YS-Bd were added as pigment derivatives. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives was 50% by weight, and the weight ratio of PY129 and PY129 sulfonated derivative was 97: 3.

Example 3
A pigment dispersion, a green colorant composition, and a green color filter were prepared in the same manner as in Example 1 except that 0.05 g of YS-Ad and 0.45 g of YS-Bd were added as pigment derivatives. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives was 10% by weight, and the weight ratio of PY129 and PY129 sulfonated derivative was 97: 3.

Example 4
A pigment dispersion, a green colorant composition, and a green color filter were produced in the same manner as in Example 1 except that 0.03 g of YS-Ad and 0.47 g of YS-Bd were added as pigment derivatives. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives was 6% by weight, and the weight ratio of PY129 and PY129 sulfonated derivative was 97: 3.

Comparative Example 2
A pigment dispersion, a green colorant composition, and a green color filter were produced in the same manner as in Example 1 except that 0.02 g of YS-Ad and 0.48 g of YS-Bd were added as pigment derivatives. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives was 4% by weight, and the weight ratio of PY129 and PY129 sulfonated derivative was 97: 3.

Example 5
A pigment dispersion, a green colorant composition, and a green color filter were produced in the same manner as in Example 1 except that 15.2 g of PY129 and 0.8 g of YS-Ad were added. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives was 100% by weight, and the weight ratio of PY129 to PY129 sulfonated derivative was 95: 5.

Example 6
A pigment dispersion, a green colorant composition, and a green color filter were produced in the same manner as in Example 1 except that 15.84 g of PY129 and 0.16 g of YS-Ad were added. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives was 100% by weight, and the weight ratio of PY129 and PY129 sulfonated derivative was 99: 1.

Example 7
A pigment dispersion, a green colorant composition, and a green color filter were produced in the same manner as in Example 1 except that 15.92 g of PY129 and 0.08 g of YS-Ad were added. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives is 100% by weight, and the weight ratio of PY129 to PY129 sulfonated derivative is 99.5: 0.5. Met.

Example 8
A pigment dispersion, a green colorant composition, and a green color filter were produced in the same manner as in Example 1 except that 13.44 g of PY129 and 2.56 g of YS-Ad were added. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives was 100% by weight, and the weight ratio of PY129 and PY129 sulfonated derivative was 84:16.

Comparative Example 3
A color pigment dispersion, a green colorant composition, and a green color filter were produced in the same manner as in Example 1 except that 16 g of PY129 was added without adding the pigment derivative. In the pigment dispersion, the weight ratio of PY129 and PY129 sulfonated derivative was 100: 0.

Example 9
Preparation of pigment dispersion using acrylic polymer 45.6 g of PG7 (38% by weight of the whole pigment), 45.6 g of PG36 (38% by weight of the whole pigment), 27.8 g of PY129 (23.3% by weight of the whole pigment), PY129 Derivative YS-Ad 0.9g (0.7% by weight of the total pigment) and Ajimoto Fine Techno "Ajispar" PB821 35% propylene glycol monomethyl ether acetate (PGMEA) solution 102.86g as an acrylic polymer, Daicel Chemical's “Cyclomer” ACA250 (45 wt% solution) 80.00 g and PGMEA 697.14 g were mixed and stirred with a homodisper to prepare a slurry. The beaker containing the slurry was connected with a circulation type bead mill disperser ("Dynomill" KDL-A manufactured by Willy et Bacofen) and a tube, and zirconia beads having a diameter of 0.3 mm were used as a medium at 3200 rpm for 3 hours. Dispersion treatment was performed to obtain a pigment dispersion. In the pigment dispersion, the amount of the pigment derivative having two sulfonic acid groups in one molecule in all pigment derivatives was 100% by weight, and the weight ratio of PY129 to PY129 sulfonated derivative was 97: 3.

Preparation of photosensitive green colorant composition 720.59 g of the obtained pigment dispersion using acrylic polymer, 9.16 g of acrylic polymer “Cyclomer” ACA250 (45 wt% solution) manufactured by Daicel Chemical Industries, polyfunctional monomer manufactured by Nippon Kayaku "Kayarad" DPHA 30.06g, Ciba Specialty Chemicals photoinitiator "Irgacure" 907 18.04g, Nippon Kayaku sensitizer "Kayacure" DETX-S 9.02g with propylene glycol monomethyl ether acetate 212.72g A total of 279.41 g of the diluted solution was added and mixed, and a surfactant “BYK333” manufactured by bic chemie was added to a total solid content of 2000 ppm, and a photosensitive green colorant composition using an acrylic resin was added. Obtained. The pigment / resin ratio (weight ratio) of this green colorant composition is 50/50.

Production of Color Filter The green colorant composition was coated on a transparent glass substrate using a spinner, and then heat-treated in a hot air oven at 90 ° C. for 10 minutes to obtain a green colorant composition coating film. The green colorant composition was applied by adjusting the spinner rotation speed so that the chromaticity of the pattern was y = 0.675 with a C light source. Next, a predetermined area is exposed through a negative mask, and “Emulgen” A-60 (HLB12.8, polyoxyethylene derivative) as a nonionic surfactant is added to a 0.04% aqueous potassium hydroxide solution (manufactured by Kao Corporation). ) Was developed by immersing with an alkali developer added at 0.1% by mass with respect to the total amount of the developer for 90 seconds, followed by washing with pure water to obtain a patterned substrate. The obtained patterned substrate was held in a hot air oven at 220 ° C. for 30 minutes to cure the acrylic resin. A green color filter was prepared as described above.

  Table 1 shows various evaluation results of color filters obtained from the pigment dispersions and colorant compositions obtained in Examples 1 to 8 and Comparative Examples 1 to 3.

Claims (6)

A pigment dispersion containing an azo metal complex pigment and / or an azomethine metal complex pigment, an azo metal complex pigment and / or a pigment derivative having a sulfonic acid group introduced into an azomethine metal complex pigment, and a solvent, A pigment dispersion characterized in that 5 to 100% by weight of the pigment derivative is an azo metal complex pigment and / or an azomethine metal complex pigment having two sulfonic acid groups in one molecule. 2. The pigment dispersion according to claim 1, wherein the azo metal complex pigment and / or the azomethine metal complex pigment is PY129. The pigment dispersion according to claim 2, wherein the mixing ratio of PY129 and the pigment derivative having a sulfonic acid group introduced into PY129 is in the range of 85:15 to 99: 1 by weight. A colorant composition containing at least a pigment, a resin, and a solvent, comprising the pigment dispersion according to any one of claims 1 to 3. The colorant composition according to claim 4, wherein the pigment contains PG7 and / or PG36. 6. A color filter having a pixel composed of a colored layer provided in a desired pattern for each color with an arbitrary number of colors, wherein the colored layer is formed by the colorant composition according to claim 4 or 5. A color filter characterized by being a colored film.