JP7325728B2 - Pigment dispersion and coloring composition for coating film formation - Google Patents

Description

TECHNICAL FIELD The present invention relates to a pigment dispersion and a coating film-forming coloring composition containing the pigment dispersion.

Conventionally, a coating film-forming coloring composition containing this type of pigment dispersion has been used as a raw material for a color filter constituting a display element such as a liquid crystal display device. In such liquid crystal display devices and the like, cold-cathode tubes have generally been used as the light source of the backlight, but in recent years, light-emitting diodes (LEDs) and organic ELs have come to be widely used. Since the image quality displayed changes when the light source is different in this way, a color tone different from the color tone of the color filter required in the conventional light source is required. In addition, image display devices for televisions in particular are required to have high image quality and high luminance. Therefore, when an LED or an organic EL is used as a light source, the colorant used in the pigment dispersion used in the production of the color filter and the coloring composition for forming a coating film containing the same has a color tone equal to or higher than that of the conventional one. However, there is a demand for a device capable of achieving higher brightness.

For example, Patent Document 1 proposes a coloring composition containing an azo pigment suitable for an organic EL display device. Patent Document 2 proposes a colorant dispersion containing a specific dye, a pigment, and a specific solvent, which is excellent in storage stability.

Japanese Patent No. 5568805 Japanese Patent No. 6155076

In the invention described in Patent Document 1, a specific azo pigment is used, but this kind of azo pigment has low heat resistance and resistance to solvents, and is likely to cause problems related to various development characteristics, so it is not suitable for color filter applications. The fact is that they are not adopted. Therefore, as a substitute for such azo pigments, attention is paid to rhodamine dyes. Patent Document 2 describes the use of such a rhodamine dye in combination with a pigment. However, in the invention described in Patent Document 2, it is said that storage stability can be obtained by using a combination of a pigment, a predetermined dye, and a predetermined solvent. It turned out that there was room.

Accordingly, an object of the present invention is to provide a pigment dispersion and a coating film-forming coloring composition which have good storage stability and can impart good brightness.

The inventor of the present invention has made intensive studies to solve the problems described above. As a result, the inventors have found that the above problems can be solved by using a combination of a specific rhodamine-based lake pigment and other pigments, and by using a combination of a specific dispersant.

A first aspect of the present invention relates to a pigment dispersion containing a lake pigment represented by the following formula (1), a pigment other than the lake pigment, a tertiary amine dispersant, a phosphate ester dispersant and a solvent.

(In Formula (1), R ¹ to R ⁴ are each independently a hydrogen atom, an optionally substituted monovalent saturated hydrocarbon group having 1 to 20 carbon atoms, or a substituent represents a monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms, wherein —CH ₂ — contained in the saturated hydrocarbon group may be replaced with —O—, —CO— or —NR ⁹ —. R ¹ and R ² may combine to form a ring together with the adjacent nitrogen atoms, and R ³ and R ⁴ may combine to form a ring together with the adjacent nitrogen atoms.
R ⁵ represents -SO ₃ ^- and/or -CO ₂ ^- .
R ⁶ and R ⁷ each independently represent a hydrogen atom or a saturated aliphatic hydrocarbon group having 1 to 6 carbon atoms.
R ⁸ is each independently -OH, -CO ₂ H, -SO ₃ H, -CO ₂ R ¹⁰ , -SO ₃ R ¹⁰ , -SO ₂ NR ¹¹ R ¹² , -CO ₂ ^- Z ⁺ or - Represents SO ₃ ⁻ Z ⁺ , where Z ⁺ represents ⁺ N(R ⁹ ) ₄ , Na ⁺ or K ⁺ .
R ⁹ represents a hydrogen atom, a monovalent saturated hydrocarbon group having 1 to 20 carbon atoms or an aralkyl group having 7 to 10 carbon atoms.
R ¹⁰ represents a monovalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a halogen atom.
R ¹¹ and R ¹² each independently represent a hydrogen atom or a monovalent saturated hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH ₂ contained in the saturated hydrocarbon group - may be replaced by -O-, -CO-, -NH- or -NR ¹⁰ -. R ¹¹ and R ¹² may combine to form a 3- to 10-membered heterocyclic ring together with the adjacent nitrogen atoms.
M represents a metal element.
n represents an integer of 0 to 3;
a represents the valence of the metal element. )

In an embodiment of the invention, the solvent may contain two or more organic solvents.

In an embodiment of the invention, the solvent may include an alkylene glycol alkyl ether acetate and an alcoholic solvent having at least one hydroxy group. In this case, the alcohol solvent may further have at least one alkoxy group.

In an embodiment of the present invention, the tertiary amine-based dispersant may be free of quaternary ammonium groups.

The second aspect of the present invention relates to a coating film-forming coloring composition comprising the pigment dispersion and a coating film-forming component.

The pigment dispersion according to the present invention has excellent storage stability due to its excellent viscosity stability, and the coating film-forming coloring composition containing the pigment dispersion can form a color filter having good brightness.

Pigment dispersions according to examples of the present invention, a lake pigment represented by the following formula (1) (hereinafter sometimes simply referred to as "lake pigment".), pigments other than the lake pigment, tertiary amine-based dispersion agent, phosphate ester dispersant and solvent.

In formula (1), R ¹ to R ⁴ are each independently a hydrogen atom, an optionally substituted monovalent saturated hydrocarbon group having 1 to 20 carbon atoms, or a substituted group. represents a monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms, wherein —CH ₂ — contained in the saturated hydrocarbon group may be replaced with —O—, —CO— or —NR ⁹ —; . R ¹ and R ² may combine to form a ring together with the adjacent nitrogen atoms. R ³ and R ⁴ may combine to form a ring together with the adjacent nitrogen atoms.
R ⁵ represents -SO ₃ ^- and/or -CO ₂ ^- .
R ⁶ and R ⁷ each independently represent a hydrogen atom or a saturated aliphatic hydrocarbon group having 1 to 6 carbon atoms.
R ⁸ is each independently -OH, -CO ₂ H, -SO ₃ H, -CO ₂ R ¹⁰ , -SO ₃ R ¹⁰ , -SO ₂ NR ¹¹ R ¹² , -CO ₂ ^- Z ⁺ or - Represents SO ₃ ⁻ Z ⁺ , where Z ⁺ represents ⁺ N(R ⁹ ) ₄ , Na ⁺ or K ⁺ .
R ⁹ represents a hydrogen atom, a monovalent saturated hydrocarbon group having 1 to 20 carbon atoms or an aralkyl group having 7 to 10 carbon atoms.
R ¹⁰ represents a monovalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a halogen atom.
R ¹¹ and R ¹² each independently represent a hydrogen atom or a monovalent saturated hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH ₂ contained in the saturated hydrocarbon group - may be replaced by -O-, -CO-, -NH- or -NR ¹⁰ -. R ¹¹ and R ¹² may combine to form a 3- to 10-membered heterocyclic ring together with the adjacent nitrogen atoms.
M represents a metal element.
n represents an integer of 0 to 3;
a represents the valence of the metal element.

By using the lake pigment represented by the formula (1) and two specific dispersants in combination with other pigments, the viscosity stability is excellent and the storage stability is excellent, making it possible to form a high-brightness coating film. Although the reason for this is not necessarily clear, it is presumed that the lake pigment is evenly distributed in the film of the color filter.

The lake pigment represented by formula (1) can be obtained, for example, by converting a dye as described in Patent Document 2 into a lake according to a conventional method.

Examples of monovalent saturated hydrocarbon groups having 1 to 20 carbon atoms for R ¹ to R ⁴ include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group and nonyl group. , decyl group, dodecyl group, hexadecyl group, icosyl group and other linear alkyl groups; isopropyl group, isobutyl group, isopentyl group, neopentyl group, 2-ethylhexyl group and other branched alkyl groups; cyclopropyl group, cyclopentyl group , a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a tricyclodecyl group, and other alicyclic saturated hydrocarbon groups having 3 to 20 carbon atoms.

A hydrogen atom contained in the saturated hydrocarbon group for R ¹ to R ⁴ may be substituted with, for example, an aromatic hydrocarbon group having 6 to 10 carbon atoms or a halogen atom.

Examples of the monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms for R ¹ to R ⁴ include phenyl group, toluyl group, xylyl group, mesityl group, propylphenyl group and butylphenyl group.

Examples of substituents that the saturated hydrocarbon group or aromatic hydrocarbon group may have include a halogen atom, -R ¹⁰ , -OH, -OR ¹⁰ , -SO ₃ ^- , -SO ₃ H, and -SO ₃ ^{-Z +} , -CO ₂ H, -CO ₂ R ¹⁰ , -SR ¹⁰ , -SO ₂ R ¹⁰ , -SO ₃ R ¹⁰ and -SO ₂ NR ¹¹ R ¹² . When —SO ₃ ^— is included as a substituent, it should be selected so that the valence of the portion having a rhodamine skeleton (framework other than metal ions) is minus 1, as shown in formula (1). is a matter of course.

Examples of the ring formed by the bonding of R ¹ and R ² together with the adjacent nitrogen atom and the ring formed by the bonding of R ³ and R ⁴ together with the adjacent nitrogen atom include the following.

Examples of monovalent saturated hydrocarbon groups having 1 to 20 carbon atoms for R ⁹ to R ¹² include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group and nonyl group. , decyl group, dodecyl group, hexadecyl group, icosyl group and other linear alkyl groups; isopropyl group, isobutyl group, isopentyl group, neopentyl group, 2-ethylhexyl group and other branched alkyl groups; cyclopropyl group, cyclopentyl group , a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a tricyclodecyl group, and other alicyclic saturated hydrocarbon groups having 3 to 20 carbon atoms.

Substituents which the saturated hydrocarbon group in R ¹¹ and R ¹² may have include a hydroxy group and a halogen atom.

—OR ¹⁰ includes, for example, methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, 2-ethylhexyloxy and icosyloxy groups.

—CO ₂ R ¹⁰ includes, for example, a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, a tert-butoxycarbonyl group, a hexyloxycarbonyl group and an icosyloxycarbonyl group.

—SR ¹⁰ includes, for example, a methylsulfanyl group, an ethylsulfanyl group, a butylsulfanyl group, a hexylsulfanyl group, a decylsulfanyl group and an icosylsulfanyl group.

—SO ₂ R ¹⁰ includes, for example, a methylsulfonyl group, an ethylsulfonyl group, a butylsulfonyl group, a hexylsulfonyl group, a decylsulfonyl group and an icosylsulfonyl group.

—SO ₃ R ¹⁰ includes, for example, a methoxysulfonyl group, an ethoxysulfonyl group, a propoxysulfonyl group, a tert-butoxysulfonyl group, a hexyloxysulfonyl group and an icosyloxysulfonyl group.

—SO ₂ NR ¹¹ R ¹² includes, for example, a sulfamoyl group;
N-methylsulfamoyl group, N-ethylsulfamoyl group, N-propylsulfamoyl group, N-isopropylsulfamoyl group, N-butylsulfamoyl group, N-isobutylsulfamoyl group, N- sec-butylsulfamoyl group, N-tert-butylsulfamoyl group, N-pentylsulfamoyl group, N-(1-ethylpropyl)sulfamoyl group, N-(1,1-dimethylpropyl)sulfamoyl group, N-(1,2-dimethylpropyl)sulfamoyl group, N-(2,2-dimethylpropyl)sulfamoyl group, N-(1-methylbutyl)sulfamoyl group, N-(2-methylbutyl)sulfamoyl group, N-(3 -methylbutyl)sulfamoyl group, N-cyclopentylsulfamoyl group, N-hexylsulfamoyl group, N-(1,3-dimethylbutyl)sulfamoyl group, N-(3,3-dimethylbutyl)sulfamoyl group, N- heptylsulfamoyl group, N-(1-methylhexyl)sulfamoyl group, N-(1,4-dimethylpentyl)sulfamoyl group, N-octylsulfamoyl group, N-(2-ethylhexyl)sulfamoyl group, N- N-1 substituted sulfamoyl groups such as (1,5-dimethyl)hexylsulfamoyl group and N-(1,1,2,2-tetramethylbutyl)sulfamoyl group;
N,N-dimethylsulfamoyl group, N,N-ethylmethylsulfamoyl group, N,N-diethylsulfamoyl group, N,N-propylmethylsulfamoyl group, N,N-isopropylmethylsulfamoyl group moyl group, N,N-tert-butylmethylsulfamoyl group, N,N-butylethylsulfamoyl group, N,N-bis(1-methylpropyl)sulfamoyl group, N,N-heptylmethylsulfamoyl group and N,N-2 substituted sulfamoyl groups such as groups.

R ⁵ may be -SO ₃ ^- and/or -CO ₂ ^- . From the viewpoint of imparting better storage stability and brightness, at least one is preferably —SO ₃ ^— .

R ⁸ is —OH, —CO ₂ H, —SO ₃ H, —CO ₂ R ¹⁰ , —SO ₃ R ¹⁰ , —SO ₂ NR ¹¹ R ¹² , —CO ₂ ^— Z ⁺ or —SO ₃ ^— Z ⁺ -CO ₂ H, -CO ₂ ^- Z ⁺ , -CO ₂ R ¹⁰ , -SO ₃ ^- Z ⁺ , -SO ₃ H or -SO ₂ NHR ¹¹ are preferred, and -SO ₃ ^- Z ⁺ , —SO ₃ H or —SO ₂ NHR ¹¹ are more preferred. n may be 0 to 3, preferably 0 to 1, and particularly preferably 0.

The C 1-6 alkyl group for R ⁶ and R ⁷ includes, for example, methyl group, ethyl group, propyl group, butyl group, pentyl group and hexyl group.

The aralkyl group having 7 to 10 carbon atoms for R ⁹ includes, for example, a benzyl group, a phenylethyl group and a phenylbutyl group.

Z ⁺ is ⁺ N( ^R9 ) ₄ , Na ⁺ or K ⁺ , preferably ⁺ N( ^R9 ) ₄ . At least two of the four R ⁹ in ⁺ N(R ⁹ ) ₄ are preferably monovalent saturated hydrocarbon groups having 5 to 20 carbon atoms. The total number of carbon atoms in four R ⁹ is preferably 20-80, more preferably 20-60.

M may be any metal atom capable of forming a lake, and examples thereof include Ca, Mg, Al, Cr, Mn, Fe, Ni, Zn, Sr, Cd, Pb, Ba and Co. Among these, Ca is particularly preferable from the viewpoint of dispersibility and brightness. The valence a can be, but is not limited to, the general valence of these metal atoms. By way of example, Ca, Mg, Mn, Fe, Ni, Zn, Sr, Cd, Pb, Ba, Co can generally be divalent cations, and Al, Cr can generally be trivalent cations.

Pigments other than the lake pigment represented by the formula (1) are not particularly limited, and may be either organic pigments or inorganic pigments, but organic pigments are preferred. Examples of organic pigments include the following when indicated by a color index number.

As a red pigment, C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 21, 22, 23, 31, 32, 38, 41, 48, 48:1, 48:2, 48:3, 48:4, 48:5, 49, 52, 52:1, 52:2, 53:1, 54, 57:1, 58, 60:1, 63, 64:1, 68, 81:1, 83, 88, 89, 95, 112, 114, 119, 122, 123, 129, 136, 144, 146, 147, 149, 150, 164, 166, 168, 169, 170, 171, 172, 175, 176, 177, 178, 179, 181, 183, 184, 185, 187, 188, 190, 193, 194, 200, 202, 206, 207, 208, 209, 210, 211, 213, 214, 216, 220, 221, 224, 226, 237, 238, 239, 242, 245, 247, 248, 251, 253, 254, 255, 256, 257, 258, 260, 262, 263, 264, 266, 268, 269, 270, 271, 272, 279, 291 and the like.

As a blue pigment, C.I. I. pigment blue 1, 15, 15:1, 15:2, 15:3, 15:4, 15:5, 15:6, 16, 17:1, 24, 24:1, 25, 26, 56, 60, 61, 62, 63, 75, 79, 80 and the like.

As a yellow pigment, C.I. I. Pigment Yellow 138, 139, 150, 180, 185 and the like.

As an orange pigment, C.I. I. Pigment Orange 43, 71, 73 and the like.

As a green pigment, C.I. I. Pigment Green 1, 4, 7, 8, 10, 36, 58, 59, 63 and the like.

As a purple pigment, C.I. I. Pigment Violet 1, 2, 3, 3:1, 3:3, 5:1, 13, 17, 19, 23, 25, 27, 29, 31, 32, 36, 37, 38, 42, 50, etc. mentioned.

Pigments other than lake pigments may be used singly or in combination of two or more of the pigments described above.

The content of the lake pigment and the pigment other than the lake pigment is preferably 8 to 20% by weight, more preferably 12 to 18% by weight, in the pigment dispersion from the viewpoint of ensuring good dispersibility. The mixing ratio A/B (by weight) of the lake pigment (A) and the pigment (B) other than the lake pigment is preferably 1/10 to 1/5.

The particle size of the pigment can be appropriately determined according to the application, etc., and those having an average primary particle size of 20 to 200 nm can be preferably used. The average primary particle size can be calculated, for example, as the arithmetic mean of the maximum widths of a plurality (eg, 50) of primary particles being imaged by a transmission electron microscope (TEM).

Depending on the type of pigment, a milling treatment may be performed in advance from the viewpoint of improving contrast, adjusting the average particle size, and the like. The milling treatment can be carried out according to a standard method depending on the type of organic pigment. Examples of such milling include solvent salt milling.

Dispersants include tertiary amine-based dispersants and phosphate ester-based dispersants. By using both of these dispersants in combination, the storage stability of the pigment dispersion and the brightness of the coating film are excellent.

The tertiary amine-based dispersant may be one containing a compound having a tertiary amine as a functional group as a main component, but preferably contains a polymer compound having a tertiary amine as a side chain as a main component. Moreover, as long as it has a tertiary amine as a functional group, it may have other functional groups, but it preferably does not contain a quaternary ammonium group. The amine value of the tertiary amine dispersant is preferably 20 to 200 mgKOH/g, more preferably 50 to 150 mgKOH/g, from the viewpoint of the brightness of the coating film. From the viewpoint of development time, 20 to 140 mgKOH/g is preferable. The amine value (amine value in terms of solid content) can be determined by a method according to DIN 16945, for example.

The main chain constituting the polymer compound having a tertiary amine as a side chain is not particularly limited, and examples thereof include polyurethane, polyester, unsaturated polyamide, phosphoric acid ester, polycarboxylic acid and its amine salt/ammonium salt/alkylamine. Oil-based dispersants such as salts, polycarboxylic acid esters, hydroxyl group-containing polycarboxylic acid esters, polysiloxanes, modified polyacrylates, (meth)acrylic acid-(meth)acrylic acid ester copolymers, (meth)acrylic acid-styrene copolymers Examples thereof include water-soluble resins such as polymers, styrene-maleic acid copolymers, and water-soluble high molecular compounds.

Commercially available products can be used as the tertiary amine-based dispersant. For example, Disperbyk LPN24102, LPN24903, LPN24956 manufactured by BYK-Chemie Japan Co., Ltd., and the like can be mentioned.

The phosphate ester-based dispersant may be composed mainly of a compound having a phosphate ester as a functional group, but is preferably composed mainly of a polymer compound having a phosphate ester as a side chain. Phosphate esters may be obtained by substituting at least one of the three hydrogen atoms contained in phosphoric acid (O=P(OH) ₃ ) with an organic group. When binding to a side chain of a polymer compound, it is preferred that one of the three hydrogen atoms is bound to the main chain and at least one of the other two is substituted with an organic group. As the main chain constituting the polymer compound having the phosphate ester in the side chain, the same one as the tertiary amine-based dispersant can be exemplified. When the tertiary amine-based dispersant and the phosphate-based dispersant have polymer compounds as main components, the main chains of the polymer compounds may be the same or different.

Commercially available phosphate ester dispersants can be used. For example, Disperbyk-111 manufactured by BYK Japan Co., Ltd., Solsperse 41000 manufactured by Lubrizol Co., Ltd., Phosphanol RE-610 manufactured by Toho Chemical Industry Co., Ltd., Disparlon PW-36 manufactured by Kusumoto Kasei Co., Ltd., Disparlon DA- 375, Disparlon DA-325 and the like.

The dispersant may contain a dispersant other than the tertiary amine-based dispersant and the phosphate ester-based dispersant. Examples thereof include surfactant-type dispersants such as anionic active agents such as naphthalenesulfonic acid formalin condensates and aromatic sulfonic acid formalin condensates, and nonionic active agents such as polyoxyethylene alkyl ethers.

The content (solid content or active ingredient) of the dispersant is preferably 10 to 40 parts by weight with respect to 100 parts by weight of the pigment from the viewpoint of ensuring good dispersibility. Further, when a pigment derivative, which will be described later, is included, it is preferably 10 to 40 parts by weight with respect to 100 parts by weight of the total of the pigment and the pigment derivative. However, the optimum amount of the dispersant to be added may be appropriately adjusted depending on the combination with the type of pigment used.

The pigment dispersion preferably contains a pigment derivative from the viewpoint of preventing aggregation of particles in the pigment dispersion to more effectively prevent an increase in viscosity and from the viewpoint of improving the contrast ratio. A pigment derivative is a compound having an organic pigment as a basic skeleton and having an acidic group or an aromatic group introduced as a substituent to a side chain. Examples of organic pigments serving as the base skeleton include quinacridone pigments, phthalocyanine pigments, azo pigments, quinophthalone pigments, isoindoline pigments, isoindolinone pigments, quinoline pigments, diketopyrrolopyrrole pigments, benzo Examples include imidazolone pigments and dioxazine pigments. The base skeleton also includes naphthalene-based, anthraquinone-based, triazine-based, quinoline-based, and other light-yellow aromatic polycyclic compounds that are not generally called dyes. Such pigment derivatives include, for example, JP-A-11-49974, JP-A-11-189732, JP-A-10-245501, JP-A-2006-265528, JP-A-8-295810, JP-A-11-199796, JP-A-2005-234478, JP-A-2003-240938, JP-A-2001-356210, JP-A-2007-186681, JP-A-2003-167112, JP-A Those described in Japanese Patent Application Laid-Open No. 2013-199470 can be used.

The content (solid content) of the pigment derivative in the pigment dispersion is preferably 2 to 15 parts by weight, more preferably 5 to 10 parts by weight, based on 100 parts by weight of the pigment, from the viewpoint of improving dispersion stability and brightness. However, the optimum amount of the pigment derivative to be added may be appropriately adjusted depending on the combination of the types of the pigment and dispersant used. In addition, when using other pigment derivatives, it is the total amount.

For the pigment dispersion, a dispersing resin may be used as a dispersing aid from the viewpoint of further improving the dispersibility of the pigment and the like. Such a dispersing resin is particularly suitable for use when the coating film-forming component, which will be described later, contains a polymerizable component, especially a photopolymerizable component. By preparing a pigment dispersion containing a dispersing resin, a pigment, a pigment derivative, a dispersant, and a solvent before adding the polymerizable component, the dispersibility of each solid content becomes good when the polymerizable component is added. . Examples of such dispersing resins include alkali-soluble resins described later. The dispersing resin may be the same resin species as the alkali-soluble resin used as the coating film-forming component, or may be a different resin species. The content of the dispersing resin is preferably 10 to 50 parts by weight with respect to 100 parts by weight of the pigment or 100 parts by weight of the total of the pigment and the pigment derivative.

The solvent can be appropriately selected according to the type of coating film-forming component described later, and examples include various organic solvents such as aromatic, ketone, ester, glycol ether, alcohol, and aliphatic are mentioned. Among these, organic solvents selected from aromatics, ketones, esters, glycol ethers, and alcohols are preferable, and organic solvents selected from glycol ethers and alcohols are more preferable, from the viewpoint of improving brightness. . The organic solvent may be used alone or in combination of two or more.

Examples of aromatic organic solvents include aromatic hydrocarbons such as toluene, xylene, and ethylbenzene.

Ketone organic solvents include, for example, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, acetylacetone, isophorone, acetophenone, cyclohexanone and the like.

Ester organic solvents include, for example, 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-ethoxypro pionate, ethylene glycol monobutyl ether acetate, ethylene glycol monomethyl ether acetate, propyl acetate, 1,3-butylene glycol diacetate and the like.

Glycol ether-based organic solvents include, for example, 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, diethylene glycol mono-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 Water-soluble ether such as ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-iso-propyl ether, propylene glycol mono-n-butyl ether, dipropylene glycol mono-n-butyl ether glycol ethers,
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, water-insoluble glycol ethers such as propylene glycol methyl ether propionate;

Examples of alcoholic organic solvents include those having at least one hydroxy group, and examples thereof include alkyl alcohols having 1 to 4 carbon atoms such as ethanol, methanol, butanol, propanol and isopropanol;
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 glycol 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, pentaerythritol, etc.
Examples thereof include alkyl alcohols having an alkoxy group as a substituent, such as 2-methoxyethanol, 2-butoxyethanol, 2-(isopentyloxy)ethanol, 2-(hexyloxy)ethanol, and 3-methoxybutanol. The number of carbon atoms in the alkyl alcohols is not particularly limited, but preferably 3-5.

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

The amount of the solvent to be added may be such that the concentration of solids containing the pigment and the like in the pigment dispersion is 10 to 30% by weight from the viewpoint of handleability.

Embodiments of the pigment dispersion of the present invention may contain other additives in addition to the components mentioned above. Other additives include antioxidants, anti-agglomeration agents, surface conditioners (leveling agents), and the like.

A pigment dispersion can be obtained, for example, by adding each of the above-described components to a known dispersing machine such as a bead mill, a sand mill, and a disper, and dispersing them. The method of adding each component is not particularly limited, and each component may be mixed at the same time and subjected to dispersion treatment. When a plurality of types of pigments are used, the pigments may be divided into two or more groups, and dispersions may be prepared in advance for each group, mixed, and dispersed again. Alternatively, each pigment dispersion may be mixed with a coating film-forming component when preparing a coating film-forming coloring composition described later.

A coating film-forming coloring composition according to an embodiment of the present invention (hereinafter sometimes referred to as "coloring composition") contains the aforementioned pigment dispersion and coating film-forming components. Thus, since the specific pigment dispersion is contained, the coating film obtained using the coating film-forming coloring composition has excellent brightness.

Coating film-forming components include, for example, polymerizable components, polymers, mixtures thereof, and the like.

Examples of polymers include thermoplastic urethane resins, (meth)acrylic resins, polyamide resins, polyimide resins, styrene/maleic acid resins, polyester resins, silicone resins, and cardo resins.

The content of the polymer in the coloring composition is preferably 10 to 40% by weight, more preferably 20 to 30% by weight, based on the total solid content of the coloring composition. When it is also contained as a dispersing resin in the pigment dispersion, it is the total amount. The molecular weight of the polymer can be determined appropriately.

Among the polymers described above, alkali-soluble resins exhibiting solubility in solutions in the alkaline range are preferred.

When an alkali-soluble resin is contained, pattern formability can be further improved when the pigment composition is applied for pattern formation, for example, in a photolithography process in manufacturing a color filter.

As such an alkali-soluble resin, for example, those described in JP-A-2009-179789 can be used. Briefly, the alkali-soluble resin is, for example, a linear organic high molecular weight polymer having at least It can be appropriately selected from alkali-soluble resins having one alkali-solubility-promoting group (eg, carboxyl group, phosphoric acid group, sulfonic acid group, etc.). Among these, more preferred are those that are soluble in an organic solvent and developable with a weakly alkaline aqueous solution. The alkali-soluble resin may be a photocrosslinking resin or a thermosetting resin. Thermosetting resins tend to be preferable from the viewpoint of improving the coloring power of the coating film and dispersion stability.

The weight average molecular weight of the alkali-soluble resin is preferably 5,000 to 50,000 from the viewpoint of developability.

Various alkali-soluble resins are commercially available, and specific examples thereof are as follows, but are not limited to these.
Showa Polymer Co., Ltd.: Lipoxy SPC-2000,
Mitsubishi Rayon Co., Ltd.: DIANAL NR series,
Diamond hamrock Co. Ltd. , manufactured by: Photomer 6173 (COOH-containing Polyurethane acrylic oligomer),
Osaka Organic Chemical Industry Co., Ltd.: Viscoat R-264, KS Resist 106, SOP-005,
Manufactured by Daicel Chemical Industries, Ltd.: Cychromer P series, Plaxel CF200 series,
Daicel UCB Co., Ltd.: Ebecryl 3800,
Nippon Shokubai Co., Ltd.: Acrycure (registered trademark) AX-3-RD-Y-503, AX-3-RD-Y-702-A, AX-3-BX-Y-10, AX-3-BX-Y -106-AP and the like.

As the polymerizable component, a photopolymerizable component is preferable because patterning can be easily performed by development (negative development).

Photopolymerizable components that can be used include photopolymerizable compounds and photoinitiators. As such photopolymerizable compounds and photopolymerization initiators, those described in JP-A-2009-179789, for example, can be used. Specifically, such a photopolymerizable compound is an addition-polymerizable compound having at least one ethylenically unsaturated double bond and having at least one, preferably two or more terminal ethylenically unsaturated bonds. selected from Such compound groups are widely known in the art, and can be used in the present invention without any particular limitation. Photopolymerizable compounds have chemical forms such as, for example, monomers, prepolymers, ie dimers, trimers and oligomers, or mixtures thereof and copolymers thereof.

Examples of monomers and copolymers thereof include unsaturated carboxylic acids (e.g., acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.), and esters and amides thereof, preferably Esters of unsaturated carboxylic acids and aliphatic polyhydric alcohol compounds, and amides of unsaturated carboxylic acids and aliphatic polyhydric amine compounds are used. In addition, addition reaction products of unsaturated carboxylic acid esters or amides having nucleophilic substituents such as hydroxyl groups, amino groups, and mercapto groups with monofunctional or polyfunctional isocyanates or epoxies, and monofunctional or polyfunctional A dehydration condensation reaction product with a functional carboxylic acid is also preferably used. In addition, addition reaction products of unsaturated carboxylic acid esters or amides having electrophilic substituents such as isocyanate groups and epoxy groups with monofunctional or polyfunctional alcohols, amines, and thiols, further halogen groups and Substitution reaction products of unsaturated carboxylic acid esters or amides having a leaving substituent such as a tosyloxy group and monofunctional or polyfunctional alcohols, amines and thiols are also suitable. As another example, it is also possible to use compounds in which the above unsaturated carboxylic acid is replaced with unsaturated phosphonic acid, styrene, vinyl ether, or the like.

The photopolymerizable compound is contained in an amount of preferably 5 to 70% by weight, more preferably 10 to 60% by weight, based on the non-volatile components in the coloring composition. Moreover, these may be used independently or may be used in combination of 2 or more types. In addition, the method of using the photopolymerizable compound can arbitrarily select an appropriate structure, formulation, and addition amount from the viewpoint of degree of polymerization inhibition by oxygen, resolution, fogging property, refractive index change, surface adhesiveness, and the like.

As the photopolymerization initiator, those described in JP-A-2009-179789 can be used.
Examples include acetophenone, ketal, benzophenone, benzoin, benzoyl, xanthone, active halogen compounds (triazine, oxadiazole, coumarin), acridine, biimidazole, and oxime ester.
Specific examples of these benzophenone-based photopolymerization initiators include benzophenone, 4,4′-bis(dimethylamino)benzophenone, 4,4′-bis(diethylamino)benzophenone, 4,4′- and dichlorobenzophenone.

The content of the photopolymerization initiator in the coloring composition is preferably 0.1 to 10% by mass, more preferably 0.5 to 5% by mass, based on the total solid content of the coloring composition. When the content of the photopolymerization initiator is within this range, it is possible to favorably advance the polymerization reaction and form a film having good strength.

The coloring composition may contain the aforementioned alkali-soluble resin when it contains a photopolymerizable component as a coating film-forming component.

If necessary, the coloring composition may contain a sensitizer (sensitizing dye), a chain transfer agent, a fluorine-based organic compound, a thermal polymerization initiator, a thermal polymerization component, a filler, a surfactant, an adhesion promoter, an oxidizing Various additives such as an inhibitor, an anti-agglomeration agent, and a surface conditioner (leveling agent) may be added.

The coloring composition can be obtained, for example, by adding each of the above-described components to a known dispersing machine such as a bead mill, sand mill, or disper, and dispersing them.
There is no particular limitation on how to add each component. For example, (i) each component constituting the coating film-forming component may be mixed with the above-described pigment dispersion, or (ii) each component constituting the above-described coating film-forming component is mixed in advance and dispersed. may be prepared as a resist composition, and mixed with the above-mentioned pigment dispersion. In addition, when multiple types of pigments are used, as described above, they are divided into two or more groups, a pigment dispersion is prepared in advance for each group, and each pigment dispersion is used as in (i). After preparing the coloring composition of each pigment group, these may be mixed and dispersed to obtain the desired coloring composition, or as in (ii), the resist composition and the pigment of each pigment group A desired coloring composition may be obtained by mixing with a dispersion and performing a dispersion treatment.

The coloring composition as described above has good dispersion stability, and the coating film obtained by using it can have good brightness. Therefore, the colored composition can be favorably applied to color filters that are widely used as constituent members of liquid crystal displays (LCDs) and organic electroluminescence (EL) displays that use LEDs or organic ELs as backlights.

Hereinafter, embodiments according to the present invention will be described based on examples.

(Production Example 1) Production of Lake Pigment In a reaction vessel, 300 parts by weight of 4-[3,6-bis(diethylamino)xanthisodium-9-yl]benzene-1,3-disulfonic acid sodium salt is added to 300 parts by weight. After dissolving 0.0 part by weight, 5.7 parts by weight of calcium chloride was added to the solution at 20 to 30° C. and stirred for 1 hour at the same temperature. A wet cake obtained by filtering the precipitated crystals was dried with a hot air dryer at 80° C. to obtain 23.6 parts by weight of the target compound. The maximum absorption wavelength λmax of the obtained compound was 565 nm (aqueous solution). The resulting compound has the formula (1) wherein R ¹ , R ² , R ³ and R ⁴ are —C ₂ H ₅ , R ⁶ and R ⁷ are hydrogen atoms, n is 0 and R ⁵ is —SO ₃ ⁻ , M ^a+ is Ca ²⁺ and has a structure represented by the following formula (2).

(Production Example 2) Production of Pigment Derivative C.I. I. 20 parts by weight of Pigment Yellow 138 (Paliotol Gelb K0961HD manufactured by BASF) and 300 parts by weight of 98% sulfuric acid were placed in a 500 ml separable flask and allowed to react at 120° C. for 5 hours to obtain a sulfonated phthalimidoquinophthalone compound. . The reaction mixture was poured into 3000 parts of water with stirring to precipitate a sulfonated phthalimidoquinophthalone compound, stirred for 30 minutes, filtered and washed with water three times. The resulting wet cake was washed with 300 parts by weight of 1% diluted sulfuric acid, filtered and washed with water. It was dried in a hot air dryer to obtain 54 parts by weight of a pigment derivative represented by the following formula (3).
The resulting pigment derivative was subjected to mass spectrometry using a liquid chromatography-mass spectrometer "LC/MS" (Electro Spray Ionization) manufactured by Hewlett-Packard Co. As a result, m/z 733 [MH]- was detected. Elemental analysis and mass spectrometry of the pigment derivative were found to be p=0.8.

The components shown in Table 1 used in the following examples and comparative examples are as follows. The components listed in Table 1 are shown in parentheses.

<Pigment>
1) C.I. I. Pigment Red 177 (PR177)
SR3C-CF, manufactured by Sinic <Dye>
1) C.I. I. Acid Red 52 (AR52)
Daiwa Red No. 106, manufactured by Daiwa Kasei Co., Ltd.

<Dispersant>
1) Phosphate ester dispersant (byk111)
Disperbyk 111, manufactured by BYK-Chemie Japan Co., Ltd.,
2) Tertiary amine dispersant (LPN24102)
Disperbyk LPN24102, manufactured by BYK-Chemie Japan Co., Ltd., amine value: 160 g KOH / g
3) Tertiary amine dispersant (LPN22956)
Disperbyk LPN22956, manufactured by BYK-Chemie Japan Co., Ltd., amine value: 160 g KOH/g
4) Tertiary amine dispersant (LPN22903)
Disperbyk LPN22903, manufactured by BYK-Chemie Japan Co., Ltd., amine value: 70 g KOH / g
5) Quaternary amine-based dispersant (T.D2001)
Terplus D2001, manufactured by Otsuka Chemical Co., Ltd.

<Dispersion resin>
1) Dispersion resin 1 (RD-Y-503)
Acrylic AX-3-RD-Y-503, manufactured by Nippon Shokubai Co., Ltd., photocrosslinking resin 2) Dispersion resin 2 (BX-Y-106-AP)
Acrylic AX-3-BX-Y-106-AP, manufactured by Nippon Shokubai Co., Ltd., thermosetting resin

<Solvent>
1) Solvent 1 (PMA)
Propylene glycol monomethyl ether acetate, manufactured by Kyowa Hakko Chemical Co., Ltd. 2) Solvent 2 (MB)
3-Methoxybutanol, manufactured by Daicel Corporation

(Examples 1 to 6, Comparative Examples 1 to 4)
<Preparation of pigment dispersion 1>
Each component was put into a sand mill so as to have the composition ratio shown in Table 1 (the unit of numerical values of the composition in Table 1 is % by weight). 400 parts by weight of φ0.8 mm zirconia beads were added to 100 parts by weight of each mixture, and dispersion treatment was performed at 2000 rpm for 30 minutes. Next, φ0.8 mm zirconia beads were removed, 400 parts by weight of φ0.1 mm zirconia beads were added, and dispersion treatment was performed at 2000 rpm for 60 minutes. After that, the zirconia beads were removed to obtain Pigment Dispersion 1.

<Preparation of pigment dispersion 2>
C. I. Pigment Yellow 139 (manufactured by BASF, Irgafor Yellow S2150CF) 13.5% by weight, 1.5% by weight of the pigment derivative obtained in Production Example 2, 2.5% by weight of a dispersant (TD2001) and a dispersant ( byk-111) 0.5% by weight, dispersing resin (Acrycure AX-3-BX-Y-106-AP) 2.0% by weight, propylene glycol monomethyl ether 7.5% by weight, propylene glycol monomethyl ether acetate 72.0% by weight. Each component was put into a sand mill so as to be 5% by weight. 400 parts by weight of φ0.8 mm zirconia beads were added to 100 parts by weight of each mixture, and dispersion treatment was performed at 2000 rpm for 60 minutes. Next, φ0.8 mm zirconia beads were removed, 400 parts by weight of φ0.05 mm zirconia beads were added, and dispersion treatment was performed at 2000 rpm for 60 minutes. After that, the zirconia beads were removed to obtain a pigment dispersion 2.

<Preparation of coloring composition for coating film formation>
As an alkali-soluble resin, Nippon Shokubai Co., Ltd., Acrycure (registered trademark) BX-Y-10 (acrylic polymer) at 12.0% by weight, and as a photopolymerizable component, a polyfunctional acrylate monomer (dipentaerythritol (Hexa/penta) acrylate, manufactured by Nippon Kayaku Co., Ltd., KAYARAD DPHA) 26.0% by weight, a photopolymerization initiator (manufactured by BASF, Irgacure 369) 4.0% by weight, PMA as a solvent 58.0% by weight % was prepared.

3.51 g of Pigment Dispersion 1, 1.77 g of Pigment Dispersion 2, and 4.72 g of coating film-forming components were mixed and stirred with a disper to obtain a coloring composition for coating film formation.

<Evaluation>
<<Viscosity of Pigment Dispersion 1>>
The viscosity increases A and B of the obtained pigment dispersion 1 were calculated as follows using an E-type viscometer "RE-80L" manufactured by Toki Sangyo Co., Ltd. Table 1 shows the measurement results.
(1) Thickening rate A (thickening rate after standing at room temperature for 1 week)
After preparing the pigment dispersion, it was allowed to stand at 45° C. for 1 day, and a part was taken out and the viscosity a1 was measured with the viscometer. The remainder was allowed to stand at room temperature for 1 week, and the viscosity a2 was measured with the viscometer. The thickening rate A was calculated by thickening rate A=viscosity a2/viscosity a1×100.
(2) Thickening rate B (thickening rate after standing at 40°C for 1 week)
After preparing the pigment dispersion, it was allowed to stand at 45° C. for 1 day, and a part was taken out and the viscosity b1 was measured with the viscometer. The remainder was allowed to stand at 40° C. for 1 week, and the viscosity b2 was measured with the viscometer. The viscosity increase rate B was calculated from the following formula: viscosity increase rate B=viscosity b2/viscosity b1×100.

<<Brightness and film thickness of coating film>>
A coloring composition for forming a coating film is applied to a non-alkali glass substrate having a thickness of 0.5 mm and a square of 100 mm using a spin coater (manufactured by Mikasa Co., Ltd., Spin Coater MS-150A), chromaticity coordinates (x, y) is (0.6860, 0.3050), and dried in a constant temperature bath at 110° C. for 70 seconds. Using an exposure device (manufactured by Sanei Electric Co., Ltd., product name: UVE-1001S type exposure light source device, YSH-100SA type ultra-high pressure mercury lamp), ultraviolet rays are applied to the coated plate so that the exposure intensity is 40 mJ / cm ^2. After irradiation and post-baking at 230° C. for 20 minutes, a coated plate for evaluation was obtained.
Luminance value (Y) and chromaticity coordinates (x, y) of each coated plate for evaluation were measured using a colorimeter (CM-3700d manufactured by Minolta). Further, the film thickness was measured by a film thickness meter (manufactured by FILMETRICS, trade name: F20-EXR). In addition, development processing was performed using a 100-fold diluted developer ("CD-150CR" manufactured by JSR) at a wide-angle nozzle and a liquid temperature of 25° C., and the development time was defined as the time when the unexposed portions were completely removed. Table 1 shows the measurement results.

As shown in Table 1, by containing a predetermined lake pigment, a tertiary amine-based dispersant, and a phosphate ester-based dispersant, the pigment dispersion has good storage stability and can be obtained using the pigment dispersion. It can be seen that the brightness of the coating film is also good. Also, if the dispersant has a low amine value, it is believed that the development time is shortened. Further, it is considered that the developing time is shortened when the acid value of the resin is high or when the molecular weight of the resin is small.

Claims (5)

Contains a lake pigment represented by the following formula (1), a pigment other than the lake pigment, a tertiary amine dispersant, a phosphate ester dispersant and a solvent,
The tertiary amine-based dispersant does not contain a quaternary ammonium group,
A pigment dispersion in which the tertiary amine dispersant has an amine value of 50 to 140 mgKOH/g .
(In Formula (1), R ¹ to R ⁴ are each independently a hydrogen atom, an optionally substituted monovalent saturated hydrocarbon group having 1 to 20 carbon atoms, or a substituent represents a monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms, wherein —CH ₂ — contained in the saturated hydrocarbon group may be replaced with —O—, —CO— or —NR ⁹ —. R ¹ and R ² may combine to form a ring together with the adjacent nitrogen atoms, and R ³ and R ⁴ may combine to form a ring together with the adjacent nitrogen atoms.
R ⁵ represents -SO ₃ - and/or -CO ₂ -.
R ⁶ and R ⁷ each independently represent a hydrogen atom or a saturated aliphatic hydrocarbon group having 1 to 6 carbon atoms.
R ⁸ is each independently -OH, -CO ₂ H, -SO ₃ H, -CO ₂ R ¹⁰ , -SO ₃ R ¹⁰ , -SO ₂ NR ¹¹ R ¹² , -CO ₂ ^- Z ⁺ or - Represents SO ₃ ⁻ Z ⁺ , where Z ⁺ represents ⁺ N(R ⁹ ) ₄ , Na ⁺ or K ⁺ .
R ⁹ represents a hydrogen atom, a monovalent saturated hydrocarbon group having 1 to 20 carbon atoms or an aralkyl group having 7 to 10 carbon atoms.
R ¹⁰ represents a monovalent saturated hydrocarbon group having 1 to 20 carbon atoms, and a hydrogen atom contained in the saturated hydrocarbon group may be substituted with a halogen atom.
R ¹¹ and R ¹² each independently represent a hydrogen atom or a monovalent saturated hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and -CH ₂ contained in the saturated hydrocarbon group - may be replaced by -O-, -CO-, -NH- or -NR ¹⁰ -. R ¹¹ and R ¹² may combine to form a 3- to 10-membered heterocyclic ring together with the adjacent nitrogen atoms.
M represents a metal element.
n represents an integer of 0 to 3;
a represents the valence of the metal element. ) 2. The pigment dispersion according to claim 1, wherein said solvent contains two or more organic solvents. 3. The pigment dispersion according to claim 1, wherein the solvent contains an alkylene glycol alkyl ether acetate and an alcoholic solvent having at least one hydroxy group. 4. The pigment dispersion according to claim 3, wherein said alcoholic solvent further has at least one alkoxy group. A coloring composition for forming a coating film, comprising the pigment dispersion according to any one of claims 1 to 4 and a component for forming a coating film.