pigment dispersion

Abstract

To provide a pigment dispersion that contains a specific green or yellow pigment and has excellent viscosity stability.SOLUTION: A pigment dispersion contains at least a pigment, a derivative, a dispersant and a solvent, the pigment is at least one selected from C.I. Pigment Green 36 and the like, the derivative is a basic triazine derivative represented by the chemical formula 1, and the dispersant is a resin dispersant with an acid value in a specific range.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a pigment dispersion containing at least a pigment, a specific derivative, a specific dispersant, and a solvent. [Background technology]

[0002] Color filters are widely used as components of liquid crystal displays (LCDs). LCDs are widely used in display devices such as monitors, televisions, notebook computers, tablet computers, and smartphones, and high image quality is required for these display devices. Meanwhile, in recent years, there has been an increasing demand for reduced power consumption from the perspective of protecting the global environment, and color filters are now required to have high brightness and high contrast.

[0003] Color filters are commonly produced by forming a coating film by a photolithography process using a colored photosensitive composition, which is prepared by dissolving or dispersing colorants such as red, green, and blue dyes or pigments in a photosensitive resin. As mentioned above, one method for improving the image quality of color filters is to increase the concentration of the dye or pigment in the colored photosensitive composition to improve color purity. However, this reduces the transmittance of light from the LCD backlight, resulting in increased power consumption. Another method for achieving high contrast is to eliminate large pigment particles and disperse the pigment in the colored photosensitive composition as small particles with a diameter equal to or smaller than the wavelength of light. However, the smaller the pigment particle size, the more likely it is to aggregate, making it difficult to uniformly disperse the pigment in the colored photosensitive composition. Therefore, there is a need for the development of pigments that can realize high-brightness, high-contrast color filters that can achieve the same brightness with less light than conventional methods without increasing the concentration of the pigment.

[0004] For example, Patent Document 1 discloses a pigment dispersion that is easy to handle and can achieve both high coloration and high brightness, and that contains a halogenated zinc phthalocyanine green pigment containing 3.5% by weight or more of chlorine atoms and a specific dispersant. By using the pigment disclosed in Patent Document 1, it is expected that the brightness and contrast of color filters will increase to a certain extent. However, since it is generally not easy to uniformly disperse a pigment in a colored photosensitive composition, methods such as using a dispersant or pigment derivative as a component constituting the colored photosensitive composition, or using a surface-treated pigment, are generally adopted.

[0005] Patent Document 2 discloses the use of hydroxyamide derivatives to provide long standby times and long-term ejection stability when used in thermal inkjet printers, and gives a specific example of a phthalimide derivative as a hydroxyamide derivative. Patent Document 3 discloses the use of a substance having a pyrrolidone ring in a recording ink containing water and polyvinylpyrrolidone to prevent hydration between the water and polyvinylpyrrolidone, and gives a specific example of phthalimide.

[0006] Patent Document 4 discloses that by using a phthalocyanine pigment and an acid-type phthalimide derivative, it is possible to suppress an increase in viscosity after preparing a phthalocyanine pigment dispersion and to suppress a decrease in contrast of a coating film after preparing a colored composition containing the dispersion.

[0007] Patent Document 5 discloses a pigment composition containing a triazine compound and an organic pigment, as a fine pigment composition that contains an organic pigment having an extremely small primary particle size and in which aggregation can be significantly suppressed. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-38584 [Patent Document 2] Japanese Patent Application Publication No. 10-204359 [Patent Document 3] Japanese Patent Application Publication No. 7-331146 [Patent Document 4] Japanese Patent Application Laid-Open No. 2018-80217 [Patent Document 5] Japanese Patent Application Laid-Open No. 2011-32374 Summary of the Invention [Problem to be solved by the invention]

[0009] The present inventors attempted to suppress the increase in viscosity after the preparation of a pigment dispersion by replacing the green or blue pigment disclosed in Patent Document 4 with a red pigment (CI Pigment Red 122 / quinacridone pigment) and using it in combination with a phthalimide derivative having an acidic group. However, although the resulting red pigment dispersion had good dispersibility, it had the problem of having a somewhat large number of coarse particles. Therefore, the inventors discovered that by using a specific base-type phthalimide derivative (a base-type phthalimide derivative represented by Chemical Formula 2) in combination with a specific dispersant (a polymer dispersant having an acid value of 80 mg KOH / g or more and 120 mg KOH / g or less and having a carboxyl group), it is possible to suppress the increase in viscosity of the red pigment dispersion while also suppressing the number of coarse particles.

[0010] [ka]

[0011] (In Chemical Formula 2, R1 to R4 each independently represent a hydrogen atom or a halogen atom. n represents an integer of 1 to 5; X1 and X2 are each independently a hydrogen atom, C 1-6 Alkyl, benzyl, phenyl or C 1-6 alkyl-NR5R6 (R5 and R6 may be the same or different and are hydrogen atoms, phenyl or C 1-6 represents alkyl.) (However, at least one of X1 and X2 is C 1-6 It is a group represented by alkyl-NR5R6.

[0012] However, the combination of this specific derivative and specific dispersant could not improve the viscosity stability of pigment dispersions containing a green pigment (CI Pigment Green 36) or a yellow pigment (CI Pigment Yellow 150 or CI Pigment Yellow 185).

[0013] An object of the present invention is to provide a pigment dispersion containing a specific green pigment or yellow pigment, which has excellent viscosity stability. [Means for solving the problem]

[0014] As a result of intensive research aimed at solving the above-mentioned problems, the present inventors have found that, in the case of a pigment dispersion containing one or more pigments selected from the group consisting of CI Pigment Green 36, CI Pigment Yellow 150, and CI Pigment Yellow 185, the viscosity stability of the pigment dispersion can be improved by using a specific basic triazine derivative in combination with a resin-type dispersant having an acid value of 50 mgKOH / g or more and 100 mgKOH / g or less, and have thus completed the present invention.

[0015] Specifically, the present invention provides: A pigment dispersion containing at least a pigment, a derivative, a dispersant, and a solvent, the pigment is one or more selected from the group consisting of CI Pigment Green 36, CI Pigment Yellow 150, and CI Pigment Yellow 185; The derivative is a basic triazine derivative represented by Chemical Formula 1, The dispersant is a resin-type dispersant having an acid value of 50 mgKOH / g or more and 100 mgKOH / g or less. It relates to pigment dispersions.

[0016] [ka]

[0017] In chemical formula 1, X1 represents -H, -OH or -NH2; X2 represents -OH or -Cl; A and B each independently represent an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; C represents a group represented by an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; Z1 and Z2 each independently represent -H, an alkyl group having 1 to 6 carbon atoms, a benzyl group, a phenyl group, or -R1-NR2R3 (R1 represents an alkylene group having 1 to 6 carbon atoms; R2 and R3 each independently represent an alkyl group having 1 to 6 carbon atoms); m and p are the numbers of the substituents A and B, respectively, and represent integers of 0 to 4; n represents an integer of 0 to 3; q is the number of substituents C and represents an integer of 0 to 4; At least one of Z1 and Z2 is a group represented by -R1-NR2R3.

[0018] When one or more pigments selected from the group consisting of CI Pigment Green 36, CI Pigment Yellow 150, and CI Pigment Yellow 185 are used as pigments, the viscosity stability of the pigment dispersion is improved by combining the basic triazine derivative represented by Chemical Formula 1 with a resin-type dispersant having an acid value of 50 mgKOH / g or more and 100 mgKOH / g or less. For red pigment dispersions containing CI Pigment Red 122, the phthalimide derivative represented by Chemical Formula 2, when used in combination with a polymeric dispersant having an acid value of 80 mgKOH / g or more and 120 mgKOH / g or less and having a carboxyl group, can suppress an increase in viscosity after preparation and also suppress an increase in the number of coarse particles. However, such an effect was not observed for pigment dispersions containing CI Pigment Green 36, CI Pigment Yellow 150, or CI Pigment Yellow 185. [Effects of the Invention]

[0019] According to the present invention, the viscosity stability of a pigment dispersion containing one or more pigments selected from the group consisting of CI Pigment Green 36, CI Pigment Yellow 150, and CI Pigment Yellow 185 can be improved. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of the present invention will be described.

[0021] The green pigment that can be used in the present invention is CI Pigment Green 36. The yellow pigment that can be used in the present invention is CI Pigment Yellow 150 or CI Pigment Yellow 185. These pigments may be used alone or in combination of two or more. Furthermore, these pigments may be subjected to a milling treatment in advance from the viewpoint of improving contrast, adjusting the average particle size, etc. The milling treatment can be carried out according to a standard method depending on the type of pigment, etc. Examples of such milling treatment include solvent salt milling.

[0022] The pigment dispersion of the present invention may contain other pigments in addition to CI Pigment Green 36, CI Pigment Yellow 150, or CI Pigment Yellow 185. Examples of such pigments include the following: Green pigments include CI Pigment Green 1, CI Pigment Green 4, CI Pigment Green 7, CI Pigment Green 8, CI Pigment Green 10, CI Pigment Green 58, CI Pigment Green 59, and CI Pigment Green 63. Yellow pigments include CI Pigment Yellow 138, CI Pigment Yellow 139, and CI Pigment Yellow 180.

[0023] The derivative that can be used in the present invention is a basic triazine derivative having the chemical structure shown in Chemical Formula 1. This derivative is characterized by having the aminobenzenesulfonic acid structure shown below between the triazine ring and the basic terminal (dialkylamino group).

[0024] [ka]

[0025] The content of the derivative in the pigment dispersion is 10 parts by weight or more and 40 parts by weight or less per 100 parts by weight of the total weight of the pigment and the derivative, and more preferably 15 parts by weight or more and 35 parts by weight or less per 100 parts by weight of the total weight of the pigment and the derivative.

[0026] The dispersant that can be used in the present invention is a resin-type dispersant having an acid value of 50 mgKOH / g or more and 100 mgKOH / g or less. Various such dispersants are commercially available, including, but not limited to, Turplus (registered trademark) MD1000 (Otsuka Chemical Co., Ltd.), Turplus (registered trademark) MD1100 (Otsuka Chemical Co., Ltd.), and HIPLAAD (registered trademark) ED-153 (Kusumoto Chemical Co., Ltd.). These dispersants may be used alone or in combination of two or more.

[0027] The type of dispersant is not particularly limited, but a resin-type dispersant with an amine value of 0 mgKOH / g is preferred.

[0028] Here, the acid value refers to the acid value per 1 g of dispersant solid content, and can be determined by potentiometric titration in accordance with JIS K 0070 (1992) (unit: mgKOH / g). The amine value refers to the amine value per 1 g of dispersant solid content, and is determined by potentiometric titration using a 0.1 N hydrochloric acid aqueous solution, and then converted to the potassium hydroxide equivalent (unit: mgKOH / g).

[0029] In the pigment dispersion of the present invention, the content of the dispersant (solid content or active ingredient) is preferably 30 to 50 parts by weight, and more preferably 33 to 45 parts by weight, per 100 parts by weight of the total solid content. Here, the "total weight of all solid content" in the pigment dispersion of the present invention refers to the combined weight of the solid content or active ingredients of the pigment, derivative, dispersant, and any additives described below. From the viewpoint of dispersion stability, the ratio of (weight of solid content or active ingredient of dispersant) / (total weight of pigment and derivative) is preferably 0.45 to 1.00, and more preferably 0.50 to 0.80. However, the optimal amount of dispersant to be added can be adjusted as appropriate depending on the type of pigment used and its combination.

[0030] The solvent that can be used in the present invention is not particularly limited, and examples thereof include various solvents such as aromatic, ketone, ester, glycol ether, alcohol, and aliphatic solvents. Among these, from the viewpoint of film-forming properties in color filter applications, solvents selected from aromatic, ketone, ester, and glycol ether solvents are preferred. The solvent may be used alone or in combination of two or more.

[0031] Examples of aromatic solvents include aromatic hydrocarbons such as toluene, xylene, and ethylbenzene.

[0032] Examples of ketone solvents include methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, acetylacetone, isophorone, acetophenone, and cyclohexanone.

[0033] Examples of ester-based solvents include ethyl acetate, n-butyl acetate, isobutyl acetate, isopropyl acetate, methyl propionate, 3-methoxybutyl acetate, ethyl glycol acetate, propylene glycol monomethyl ether acetate (PMA), propylene glycol monoethyl ether acetate, 3-methyl-3-methoxybutyl acetate, methyl monochloroacetate, ethyl monochloroacetate, butyl monochloroacetate, methyl acetoacetate, ethyl acetoacetate, butyl carbitol acetate, butyl lactate, ethyl 3-ethoxypropionate, ethylene glycol monobutyl ether acetate, ethylene glycol monomethyl ether acetate, propyl acetate, and 1,3-butylene glycol diacetate.

[0034] Examples of glycol ether solvents include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-propyl ether, ethylene glycol mono-iso-propyl ether, diethylene glycol mono-iso-propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol mono-n-butyl ether, ethylene glycol mono-t-butyl ether, and diethylene glycol mono- water-soluble glycol ethers such as t-butyl ether, 1-methyl-1-methoxybutanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-t-butyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-iso-propyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-iso-propyl ether, propylene glycol mono-n-butyl ether, and dipropylene glycol mono-n-butyl ether; Examples of the water-insoluble glycol ethers include ethylene glycol monohexyl ether, ethylene glycol-2-ethylhexyl ether, ethylene glycol phenyl ether, diethylene glycol-n-hexyl ether, diethylene glycol-2-ethylhexyl ether, propylene glycol monobutyl ether, dipropylene glycol monobutyl ether, dipropylene glycol propyl ether, and propylene glycol methyl ether propionate.

[0035] Examples of alcohol-based solvents include alkyl alcohols having 1 to 4 carbon atoms, such as ethanol, methanol, butanol, propanol, and isopropanol; Examples of the suitable glycol include ethylene glycol, propylene glycol, diethylene glycol, pentamethylene glycol, trimethylene glycol, 2-butene-1,4-diol, 2-ethyl-1,3-hexanediol, 2-methyl-2,4-pentanediol, tripropylene glycol, polyethylene glycols with a molecular weight of 2000 or less, 1,3-propylene glycol, isopropylene glycol, isobutylene glycol, 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, glycerin, mesoerythritol, and pentaerythritol.

[0036] Examples of aliphatic solvents include aliphatic hydrocarbons such as n-pentane, n-hexane, and n-heptane.

[0037] The amount of solvent added can be adjusted so that the concentration of the total solids, including pigments, etc., is 15 to 50% by weight.

[0038] The pigment dispersion of the present invention may contain other additives in addition to the above-mentioned components, as necessary. Examples of other additives include antioxidants, anti-aggregation agents, surface conditioners (leveling agents), etc.

[0039] The pigment dispersion of the present invention can be prepared, for example, by adding the above-mentioned components to a known dispersing machine such as a bead mill, a sand mill, a disperser, etc. The method of adding the components is not particularly limited, and the components may be mixed simultaneously and then subjected to a dispersion treatment. For example, when multiple types of pigments are used, dispersions may be prepared in advance for each pigment, and then these dispersions may be mixed and subjected to a dispersion treatment again.

[0040] As an example, the case of dispersion treatment using a sand mill will be described. First, a pigment, a dispersant, and beads as a dispersion medium are charged into a sand mill. As beads, glass beads, zirconia beads, etc. with a particle diameter of 0.01 to 1 mm can be used. The amount of beads used is preferably 2 to 6 parts by weight per 1 part by weight of the pigment dispersion. Then, the sand mill is operated to perform dispersion treatment. The dispersion treatment conditions are preferably approximately 1000 to 2000 rpm for 1 to 20 hours. After dispersion treatment, the beads are removed by filtration or the like to obtain the pigment dispersion.

[0041] The pigment content in the pigment dispersion of the present invention is preferably 0.01 to 30 parts by weight, more preferably 1 to 20 parts by weight, per 100 parts by weight of the pigment dispersion.

[0042] (CI Pigment Green 36 micronization process) 500 parts by weight of CI Pigment Green 36 (Heubach, Monastral® Green 6Y-CL), 3000 parts by weight of anhydrous sodium sulfate, and 910 parts by weight of polyethylene glycol were charged into a double-arm kneader (Inoue Seisakusho, 5 L kneader) and kneaded for 7 hours while adjusting the temperature inside the kneader to 90°C. The kneaded mixture was transferred to a temperature-controllable tank containing 9000 parts by weight of water and stirred at 60°C for 1 hour. After stirring, 180 parts by weight of 35% hydrochloric acid was added and stirred for 1 hour. The contents were filtered, washed with water, dried, and pulverized to obtain finely divided CI Pigment Green 36.

[0043] (CI Pigment Yellow 150) As CI Pigment Yellow 150, Levasclean® Yellow G02 manufactured by Lanxess was used as is without being micronized.

[0044] (CI Pigment Yellow 185 micronization process) 600 parts by weight of CI Pigment Yellow 185 (BASF, Paliotol® Yellow D1155), 2400 parts by weight of anhydrous sodium sulfate, and 850 parts by weight of diethylene glycol were charged into a twin-arm kneader (Inoue Seisakusho Co., Ltd., 5 L kneader) and kneaded for 11 hours while adjusting the temperature inside the kneader to 50°C. The kneaded mixture was transferred to a temperature-controllable tank containing 12,000 parts by weight of water and stirred at 60°C for 30 minutes. After stirring, 500 parts by weight of 25% aqueous ammonia was added and stirred for 1 hour. The contents were filtered, washed with hydrochloric acid, washed with water, dried, and pulverized to obtain finely divided CI Pigment Yellow 185.

[0045] As the derivatives, derivative 1 represented by chemical formula 3 (included in the derivatives represented by chemical formula 1) and derivative 2 represented by chemical formula 4 were used as a comparative derivative.

[0046] [ka]

[0047] [ka]

[0048] (Production method of derivative 1) 195 parts by weight of diethylaminopropylamine and 234 parts by weight of 4-acetaminobenzenesulfonyl chloride were added to 5,000 parts by weight of cold water and stirred at 50°C for 30 minutes, then heated to 85°C. 350 parts by weight of 35% hydrochloric acid was then added and stirred for 3 hours to obtain reaction mixture a. 184 parts by weight of cyanuric chloride was added to the cooled reaction mixture a and stirred at 5°C for 1 hour to obtain reaction mixture b. 254 parts by weight of 4,4'-methylenedi-2,6-xylidine (Nippon Kayaku Co., Ltd., KAYABOND® C-200S) was added to 10,000 parts by weight of water and stirred to obtain reaction mixture c. Reaction mixture b and reaction mixture c were mixed, heated to 85°C, and stirred for 2 hours. The contents were filtered, washed with water, dried, and pulverized to obtain 567 parts by weight of Derivative 1 represented by Chemical Formula 1.

[0049] (Production method of derivative 2) 8.5 parts by weight of cyanuric chloride and 9.6 parts by weight of sulfanilic acid were added to 130 parts by weight of water and reacted at 7.5°C for 1 hour to obtain reaction mixture d. 11.8 parts by weight of 4,4'-methylenedi-2,6-xylidine (Nippon Kayaku Co., Ltd., KAYABOND (registered trademark) C-200S) was added to 130 parts by weight of water and stirred to obtain reaction mixture e. Reaction mixture d and reaction mixture e were mixed, heated to 20°C and stirred for 30 minutes, then heated to 85°C and stirred for 1 hour. The contents were filtered, the residue was washed with water, and then left to dry overnight in a constant temperature bath at 95°C to obtain 25 parts by weight of derivative 2.

[0050] The dispersants used were Turplus (registered trademark) MD1100 (Otsuka Chemical Co., Ltd. / acid value = 85 mg KOH / g, amine value = 0 mg KOH / g) and HIPLAAD (registered trademark) ED-153 (Kusumoto Chemical Co., Ltd. / acid value = 55 mg KOH / g, amine value = 0 mg KOH / g).

[0051] [Example of pigment dispersion manufacturing] (Dispersion No.1) A container was charged with 9.6 parts by weight of finely divided CI Pigment Green 36, 2.4 parts by weight of Derivative 1, 6.0 parts by weight of Turplus (registered trademark) MD1100 as a dispersant, and 82.0 parts by weight of PMA as a solvent. 400 parts by weight of 0.5 mm zirconia beads were added, and the mixture was dispersed for 60 minutes using a paint shaker. The 0.5 mm zirconia beads were then removed to obtain Dispersion No. 1.

[0052] (Dispersion No.2) Dispersion No. 2 was obtained in the same manner as Dispersion No. 1, except that Derivative 2 was used instead of Derivative 1.

[0053] (Dispersion No.3) Dispersion No. 3 was obtained in the same manner as Dispersion No. 1, except that ED-153 was used instead of MD1100.

[0054] (Dispersion No.4) Dispersion No. 4 was obtained in the same manner as Dispersion No. 3, except that Derivative 2 was used instead of Derivative 1.

[0055] (Dispersion No.5) Dispersion No. 5 was obtained in the same manner as Dispersion No. 1 except that CI Pigment Yellow 150 was used as the pigment.

[0056] (Dispersion No.6) Dispersion No. 6 was obtained in the same manner as Dispersion No. 5, except that Derivative 2 was used instead of Derivative 1.

[0057] (Dispersion No.7) Dispersion No. 7 was obtained in the same manner as Dispersion No. 1, except that finely divided CI Pigment Green 36 and CI Pigment Yellow 150 were used in a weight ratio of 80:20.

[0058] (Dispersion No.8) Dispersion No. 8 was obtained in the same manner as Dispersion No. 7, except that Derivative 2 was used instead of Derivative 1.

[0059] (Dispersion No.9) Dispersion No. 9 was prepared in the same manner as Dispersion No. 1, except that micronized CI Pigment Green 36 and micronized CI Pigment Yellow 185 were used in a weight ratio of 90:10.

[0060] (Dispersion No.10) Dispersion No. 10 was obtained in the same manner as Dispersion No. 9, except that Derivative 2 was used instead of Derivative 1.

[0061] (Dispersion No.11) Dispersion No. 11 was prepared in the same manner as Dispersion No. 1, except that finely divided CI Pigment Green 36 and finely divided CI Pigment Yellow 185 were used in a weight ratio of 80:20.

[0062] (Dispersion No.12) Dispersion No. 12 was obtained in the same manner as Dispersion No. 11, except that Derivative 2 was used instead of Derivative 1.

[0063] [Viscosity measurement] Dispersions No. 1 to No. 12 were stored in a thermostatic chamber at 45°C for 24 hours, and the viscosity after storage was measured. The viscosity was measured by adjusting the dispersion to 25°C and using an E-type viscometer (Toki Sangyo Co., Ltd., TV-22).

[0064] Table 1 shows the type, amount (parts by weight) and weight ratio of pigments, type and amount (parts by weight) of derivatives, type and amount (parts by weight) of dispersants, amount of solvent added, and viscosity after 24 hours of storage at 45°C for dispersions No. 1 to No. 12. In Table 1, G36 represents CI Pigment Green 36, Y150 represents CI Pigment Yellow 150, and Y185 represents CI Pigment Yellow 185. The amount (parts by weight) of each pigment added represents the weight part of the solid content or active ingredient.

[0065] [Table 1]

[0066] Dispersion No. 6 gelled immediately after preparation, making it impossible to measure its viscosity. After 24 hours of storage at 45°C, the viscosities of dispersions Nos. 2, 4, 8, 10, and 12 exceeded 900 mPa·s. In contrast, the viscosities of dispersions Nos. 1, 3, 5, 7, 9, and 11 were low, at 65.4 mPa·s or less. Table 1 confirms that dispersions combining Derivative 1 with MD1100 or ED-153 had low viscosity and excellent viscosity stability even after 24 hours of storage at 45°C.

[0067] From the above, it has been confirmed that a pigment dispersion using one or more pigments selected from the group consisting of CI Pigment Green 36, CI Pigment Yellow 150, and CI Pigment Yellow 185 has excellent viscosity stability during storage when combined with a derivative represented by Chemical Formula 1 (Derivative 1) and a resin-type dispersant having an acid value of 50 mgKOH / g or more and 100 mgKOH / g or less. [Industrial Applicability]

[0068] The pigment dispersions of the present invention are useful in the manufacture of color filters such as those used in displays or image sensors.

Claims

[Claim 1] A pigment dispersion containing at least a pigment, a derivative, a dispersant, and a solvent, the pigment is one or more selected from the group consisting of CI Pigment Green 36, CI Pigment Yellow 150, and CI Pigment Yellow 185; The derivative is a basic triazine derivative represented by Chemical Formula 1, The dispersant is a resin-type dispersant having an acid value of 50 mgKOH / g or more and 100 mgKOH / g or less. Pigment dispersion. 【Chemistry 1】 (In chemical formula 1, X １ is —H, —OH or —NH ２ represents; X ２ represents —OH or —Cl; A and B each independently represent an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; C represents a group represented by an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; Z １ and Z ２ are each independently —H, an alkyl group having 1 to 6 carbon atoms, a benzyl group, a phenyl group, or —R １ -NR ２ R ３ (R １ represents an alkylene group having 1 to 6 carbon atoms; R ２ and R ３ each independently represents an alkyl group having 1 to 6 carbon atoms; m and p are the numbers of the substituents A and B, respectively, and represent integers of 0 to 4; n represents an integer of 0 to 3; q is the number of substituents C and represents an integer of 0 to 4; Z １ and Z ２ At least one of the １ -NR ２ R ３ is a group represented by the formula:

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