JP2012203144A - Ink for color filter, color filter using the ink and method of manufacturing the same, and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink for a color filter which has good color reproducibility, brightness, and contrast, is excellent in ink storage properties such as heat stability, and is excellent in ink jet suitability such as printing stability (ink jet ejection stability), and credibility.SOLUTION: An ink for a color filter contains at least a pigment as a colorant and a thermosetting resin, in which the pigment is C.I.Pigment Red 254, C.I.Pigment Red 177, and C.I.Pigment Yellow 180.

Description

  The present invention is a color filter ink having excellent color reproducibility, brightness and contrast, excellent ink storage stability such as thermal stability, ink jet stability such as printing stability (inkjet ejection stability), and excellent reliability. The present invention relates to a color filter using the ink, a manufacturing method thereof, and a display device.

  Conventionally, various color filter inks having a pixel portion in which a plurality of colors (usually, three primary colors of red (R), green (G), and blue (B)) are arranged in a predetermined order have been developed.

For example, Japanese Patent Application Laid-Open No. 2007-177179 has good chromaticity and high color purity even when used in a large-screen liquid crystal display device such as a notebook personal computer display or a television monitor. For the purpose of providing a color filter that can be realized, a specific pigment is used to form pixels of a color filter having red (R) pixels, green (G) pixels, and blue (B) pixels. Each color ink is disclosed (Patent Document 1).
However, when this ink is used, there is a problem that the hue of red (R) does not reach the required level.

JP 2007-124202 A also aims at providing an ink-jet ink for a color filter that can increase luminance and contrast when a pixel is formed using an ink-jet method to realize a specific color. A specific color ink-jet ink for a color filter containing three specific pigments is disclosed. (Patent Document 2).
However, when this inkjet ink is used, the total color balance and contrast when used in combination with other colors cannot be obtained sufficiently.

JP 2007-177179 A JP 2007-124202 A

  The object of the present invention is for color filters having good color reproducibility, brightness and contrast, excellent ink storage stability such as thermal stability, and excellent inkjet reliability such as printing stability (inkjet ejection stability) and reliability. To provide ink.

[1]
A color filter ink comprising at least a pigment as a colorant and a binder resin,
The pigment is C.I. I. Pigment red 254, C.I. I. Pigment red 177, and C.I. I. Pigment Yellow 180, a color filter ink.
[2]
C. above. I. Pigment red 254, C.I. I. Pigment red 177, and C.I. I. The color filter ink according to [1], wherein the pigment yellow 180 has a weight ratio of 1 to 10: 1 to 4: 1.
[3]
The color filter ink according to [1] or [2], wherein the pigment has a particle diameter of 50 nm or less.
[4]
The color filter ink according to any one of [1] to [3], wherein the binder resin is a thermosetting resin.
[5]
The color filter ink according to any one of [1] to [4], further comprising a water-soluble organic solvent.
[6]
The color filter ink according to any one of [1] to [5], which is used for ejection by an inkjet method.
[7]
A color filter having a pixel pattern formed by an inkjet method using the color filter ink according to any one of [1] to [6].
[8]
[1] to [6] is a method of manufacturing a color filter by an ink jet method using the color filter ink described in any one of the above, and in each light transmission region that transmits light of a transparent substrate on which a partition wall is formed in advance. A step of discharging the ink from the inkjet head to store the ink in each light transmission region partitioned by the partition; a step of drying the ink stored in each light transmission region to form a pixel pattern; and the pixel And a step of forming a protective layer so as to cover the pattern. A method for producing a color filter by an ink jet method.
[9] A liquid crystal display device in which a display side substrate and a liquid crystal driving side substrate are opposed to each other and liquid crystal is sealed between the two, and the display side substrate is the color filter according to [7], or [ 8. A liquid crystal display device, wherein the liquid crystal display device is a color filter manufactured by the method for manufacturing a color filter according to [8].

According to the present invention, the color reproducibility, brightness and contrast are good, the ink storage stability such as thermal stability is excellent, and the color filter is excellent in ink jet appropriateness and reliability such as printing stability (inkjet ejection stability). Ink is obtained.
The color filter of the present invention is a color filter provided with pixels having good color reproducibility, luminance, and contrast.
In addition, the color filter manufacturing method according to the present invention can manufacture a color filter having pixels with good color reproducibility, brightness, and contrast with high productivity.
Further, according to the present invention, a display device with high quality and high productivity can be obtained.

It is a principal part longitudinal cross-sectional view which illustrates the manufacturing process of the color filter in this invention, (a) is a partition formation process, (b) is a pixel pattern formation process, (c) is a drying process, (d) is protection. The layer forming step and (e) show the common electrode forming step. It is a principal part longitudinal cross-sectional view which illustrates the liquid crystal display device which has a color filter manufactured by the manufacturing method of the color filter in this invention. It is a top view of the color filter manufactured by the manufacturing method of the color filter in this invention. It is a figure which illustrates the outline | summary of the color filter manufacturing apparatus used for the manufacturing method of the color filter in this invention. It is a partial cross section which illustrates the principal part of the inkjet head used for the manufacturing method of the color filter in this invention. It is a top view which illustrates the arrangement | positioning of each nozzle in the inkjet head used for the manufacturing method of the color filter in this invention, and the filter element in the board | substrate with which the partition was formed.

  Hereinafter, the present invention will be described in detail based on preferred embodiments thereof.

(Color filter ink)
As described above, the present invention is a color filter ink containing at least a pigment as a colorant and a binder resin,
The pigment is C.I. I. Pigment red 254, C.I. I. Pigment red 177, and C.I. I. Pigment Yellow 180 is contained at least.

  Since the color filter ink of the present invention has such a configuration, it has good color reproducibility, brightness, contrast, excellent ink storage stability such as thermal stability, printing stability (inkjet ejection stability), etc. The ink jet is suitable and reliable.

The pigment as the colorant used in the present invention is C.I. I. Pigment red 254, C.I. I. Pigment red 177, and C.I. I. Pigment Yellow 180 is contained at least.
C. above. I. Pigment red 254, C.I. I. Pigment red 177, and C.I. I. The weight ratio of Pigment Yellow 180 (red 254: red 177: yellow 180) is preferably 1 to 10: 1 to 4: 1. Within such a preferable weight ratio range, a beautiful image with good color reproduction can be provided.

  The particle diameter of these pigments is preferably 50 nm or less, particularly 40 nm or less. By using a pigment having such a particle size range, a clear image with high transparency and high luminance can be provided.

The pigment in the color filter ink of the present invention may be configured to include only the above three pigments, but other pigments may be used as appropriate.
As such other pigments, any one of an organic colorant and an inorganic colorant can be selected and used. As the organic colorant, for example, dyes, organic pigments, natural pigments, and the like can be used. Moreover, as an inorganic coloring agent, an inorganic pigment, an extender pigment, etc. can be used, for example. Among these, organic pigments are preferably used because they have high color developability and high heat resistance. As organic pigments, for example, compounds classified as Pigments in the Color Index (CI; issued by The Society of Dyersand Colorists), specifically, the following Color Index (CI) numbers are attached. Things can be mentioned.

  For example, CI Pigment Yellow 1, CI Pigment Yellow 3, CI Pigment Yellow 12, CI Pigment Yellow 13, CI Pigment Yellow 14, CI Pigment Yellow 15, CI Pigment Yellow 16, CI Pigment Yellow 17, CI Pigment Yellow 20, CI Pigment Yellow 24, CI Pigment Yellow 31, CI Pigment Yellow 55, CI Pigment Yellow 60, CI Pigment Yellow 61, CI Pigment Yellow 65, CI Pigment Yellow 71, CI Pigment Yellow 73, CI Pigment Yellow 74, CI Pigment Yellow 81, CI Pigment Yellow 81 83, CI Pigment Yellow 93, CI Pigment Yellow 95, CI Pigment Yellow 97, CI Pigment Yellow 98, CI Pigment Yellow 1 00, CI Pigment Yellow 101, CI Pigment Yellow 104, CI Pigment Yellow 106, CI Pigment Yellow 108, CI Pigment Yellow 109, CI Pigment Yellow 110, CI Pigment Yellow 113, CI Pigment Yellow 114, CI Pigment Yellow 116, CI Pigment Yellow 117, CI Pigment Yellow 119, CI Pigment Yellow 120, CI Pigment Yellow 126, CI Pigment Yellow 127, CI Pigment Yellow 128, CI Pigment Yellow 129, CI Pigment Yellow 138, CI Pigment Yellow 139, CI Pigment Yellow 151, CI Pigment Yellow 152, CI Pigment Yellow 153, CI Pigment Yellow 154, CI Pigment Yellow 155, C.I. Pigment Yellow 156, C.I. Pigment Yellow 166, C.I. Pigment Yellow 168, and C.I. Pigment Yellow 175.

  For example, CI Pigment Orange 1, CI Pigment Orange 5, CI Pigment Orange 13, CI Pigment Orange 14, CI Pigment Orange 16, CI Pigment Orange 17, CI Pigment Orange 24, CI Pigment Orange 34, CI Pigment Orange 36, CI Pigment Orange 38, CI Pigment Orange 40, CI Pigment Orange 43, CI Pigment Orange 46, CI Pigment Orange 49, CI Pigment Orange 51, CI Pigment Orange 61, CI Pigment Orange 63, CI Pigment Orange 64, CI Pigment Orange 71, CI Pigment Orange 71 73; CI Pigment Violet 1, CI Pigment Violet 19, CI Pigment Violet 23, CI Pigment Violet 29, CI Pigment And CI Pigment Violet 36, C.I. Pigment Violet 38, and CI Pigment Violet 38.

  For example, CI Pigment Red 1, CI Pigment Red 2, CI Pigment Red 3, CI Pigment Red 4, CI Pigment Red 5, CI Pigment Red 6, CI Pigment Red 7, CI Pigment Red 8, CI Pigment Red 9, CI Pigment Red 10, CI Pigment Red 11, CI Pigment Red 12, CI Pigment Red 14, CI Pigment Red 15, CI Pigment Red 16, CI Pigment Red 17, CI Pigment Red 18, CI Pigment Red 19, CI Pigment Red 21, CI Pigment Red 22, CI Pigment Red 23, CI Pigment Red 30, CI Pigment Red 31, CI Pigment Red 32, CI Pigment Red 37, CI Pigment Red 38, CI Pigment Red 40, CI Pigment Tread 41, CI Pigment Red 42, CI Pigment Red 48: 1, CI Pigment Red 48: 2, CI Pigment Red 48: 3, CI Pigment Red 48: 4, CI Pigment Red 49: 1, CI Pigment Red 49: 2, CI Pigment Red 50: 1, CI Pigment Red 52: 1, CI Pigment Red 53: 1, CI Pigment Red 57, CI Pigment Red 57: 1, CI Pigment Red 57: 2, CI Pigment Red 58: 2, CI Pigment Red 58: 4, CI Pigment Red 60: 1, CI Pigment Red 63: 1, CI Pigment Red 63: 2, CI Pigment Red 64: 1, CI Pigment Red 81: 1, CI Pigment Red 83, CI Pigment Red 88, CI Pigment Red 90: 1, CI Pigme Tread 97, CI Pigment Red 101, CI Pigment Red 102, CI Pigment Red 104, CI Pigment Red 105, CI Pigment Red 106, CI Pigment Red 108, CI Pigment Red 112, CI Pigment Red 113, CI Pigment Red 114, CI Pigment Red 122, CI Pigment Red 123, CI Pigment Red 144, CI Pigment Red 146, CI Pigment Red 149, CI Pigment Red 150, CI Pigment Red 151, CI Pigment Red 166, CI Pigment Red 168, CI Pigment Red 170, CI Pigment Red 171, CI Pigment Red 172, CI Pigment Red 174, CI Pigment Red 175, CI Pigment Red 176, CI Pigment Red 178, CI Pigment Red 179, CI Pigment Red 180, CI Pigment Red 185, CI Pigment Red 187, CI Pigment Red 188, CI Pigment Red 190, CI Pigment Red 193, CI Pigment Red 194, CI Pigment Red 202, CI Pigment Red 206, CI Pigment Red 207, CI Pigment Red 208, CI Pigment Red 209, CI Pigment Red 215, CI Pigment Red 216, CI Pigment Red 220, CI Pigment Red 224, CI Pigment Red 226, CI Pigment Red 242, CI Pigment Red 243, CI pigment red 245, CI pigment red 255, CI pigment red 264, and CI pigment red 265.

  Specific examples of the inorganic pigment or extender pigment include titanium oxide, barium sulfate, calcium carbonate, zinc white, lead sulfate, yellow lead, zinc yellow, red rose (red iron (III) oxide), cadmium red, amber, etc. Can be mentioned. In the present invention, other pigments can be used alone or in admixture of two or more.

  In the color filter ink of the present invention, the pigment content is usually 4 to 12% by weight, preferably 8 to 9% by weight, based on the total amount of the ink.

  The binder resin used in the color filter ink of the present invention functions as a binder for the pigment, and a thermosetting resin is preferably used. By using a thermosetting resin, the hardness and heat resistance of the colored portion can be improved.

  As the binder resin, an appropriate resin can be used as long as it acts as a binder for the pigment. In particular, an ethylenically unsaturated monomer having one or more carboxyl groups (hereinafter simply referred to as “carboxyl group-containing unsaturated monomer”) and other copolymerizable ethylenically unsaturated monomers (hereinafter referred to as “carboxyl group-containing unsaturated monomers”). , A copolymer with “other unsaturated monomer (b1)” (hereinafter referred to as “carboxyl group-containing copolymer (B1)”).

  Examples of the carboxyl group-containing unsaturated monomer include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, α-chloroacrylic acid, cinnamic acid; maleic acid, maleic anhydride, fumaric acid, Unsaturated dicarboxylic acids (anhydrides) such as itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride and mesaconic acid; trivalent or higher unsaturated polycarboxylic acids (anhydrides); succinic acid mono (2- Polyvalent carboxylic acid having two or more valences such as acryloyloxyethyl), succinic acid mono (2-methacryloyloxyethyl), phthalic acid mono (2-acryloyloxyethyl), phthalic acid mono (2-methacryloyloxyethyl) Mono [(meth) acryloyloxyalkyl] esters of acids; ω-carboxypolycaprolactone monoacrylate, ω-carboxypolycap It can be mentioned mono (meth) acrylates such as polymers having a carboxyl group and a hydroxyl group at both terminals such as lactone monomethacrylate. Succinic acid mono (2-acryloyloxyethyl) and phthalic acid mono (2-acryloyloxyethyl) are commercially available under the trade names M-5300 and M-5400 (manufactured by Toagosei Co., Ltd.), respectively. Has been. These carboxyl group-containing ethylenically unsaturated monomers can be used alone or in admixture of two or more.

  Other unsaturated monomers (b1) include, for example, styrene, α-methylstyrene, o-vinyltoluene, m-vinyltoluene, p-vinyltoluene, p-chlorostyrene, o-methoxystyrene, m -Methoxystyrene, p-methoxystyrene, o-vinyl benzyl methyl ether, m-vinyl benzyl methyl ether, p-vinyl benzyl methyl ether, o-vinyl benzyl glycidyl ether, m-vinyl benzyl glycidyl ether, p-vinyl benzyl glycidyl ether Aromatic vinyl compounds such as indene and indene such as 1-methylindene; methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, n-propyl methacrylate, i-propyl acrylate , I-propyl methacrylate, n-butyl acrylate, n-butyl methacrylate, i-butyl acrylate, i-butyl methacrylate, sec-butyl acrylate, sec-butyl methacrylate, t-butyl acrylate, t-butyl methacrylate, 2-hydroxyethyl Acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 2-hydroxybutyl acrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl acrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, Allyl acrylate, allyl methacrylate, benzyl acrylate, benzyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, phenyl acrylate, phenyl methacrylate, 2-methoxyethyl acrylate, 2-methoxyethyl methacrylate, 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, methoxydiethylene Glycol acrylate, methoxydiethylene glycol methacrylate, methoxytriethylene glycol acrylate, methoxytriethylene glycol methacrylate, methoxypropylene glycol acrylate, methoxypropylene glycol methacrylate, methoxydipropylene glycol acrylate, methoxydipropylene glycol Acrylate, isobornyl acrylate, isobornyl methacrylate, dicyclopentadienyl acrylate, dicyclopentadienyl methacrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxy-3-phenoxypropyl methacrylate, glycerol monoacrylate, Unsaturated carboxylic esters such as glycerol monomethacrylate;

  2-aminoethyl acrylate, 2-aminoethyl methacrylate, 2-dimethylaminoethyl acrylate, 2-dimethylaminoethyl methacrylate, 2-aminopropyl acrylate, 2-aminopropyl methacrylate, 2-dimethylaminopropyl acrylate, 2-dimethylaminopropyl Unsaturated carboxylic acid aminoalkyl esters such as methacrylate, 3-aminopropyl acrylate, 3-aminopropyl methacrylate, 3-dimethylaminopropyl acrylate and 3-dimethylaminopropyl methacrylate; glycidyl unsaturated carboxylic acid such as glycidyl acrylate and glycidyl methacrylate Esters; vinyl acetate, vinyl propionate, vinyl butyrate, vinyl benzoate and other carboxylate vinyl esters; vinyl Unsaturated ethers such as til ether, vinyl ethyl ether, allyl glycidyl ether, methallyl glycidyl ether; vinyl cyanide compounds such as acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, vinylidene cyanide; acrylamide, methacrylamide, α-chloro Unsaturated amides or unsaturated imides such as acrylamide, N-2-hydroxyethylacrylamide, N-2-hydroxyethylmethacrylamide, and maleimide; Aliphatic conjugated dienes such as 1,3-butadiene, isoprene, chloroprene; polystyrene , Polymethyl acrylate, polymethyl methacrylate, poly-n-butyl acrylate, poly-n-butyl methacrylate, polysiloxane, etc. There may be mentioned macromonomers or the like having a mono methacryloyl group. These other unsaturated monomers (b1) can be used alone or in admixture of two or more.

  As the carboxyl group-containing copolymer (B1), (1) acrylic acid and / or methacrylic acid and (2) styrene, methyl acrylate, methyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, benzyl acrylate, benzyl A copolymer with at least one selected from the group of methacrylate, polystyrene macromonomer and polymethyl methacrylate macromonomer is preferred.

  Specific examples of preferred carboxyl group-containing copolymer (B1) include acrylic acid / benzyl acrylate copolymer, acrylic acid / styrene / methyl acrylate copolymer, acrylic acid / styrene / benzyl acrylate copolymer, acrylic acid / Methyl acrylate / polystyrene macromonomer copolymer, acrylic acid / methyl acrylate / polymethyl methacrylate macromonomer copolymer, acrylic acid / benzyl acrylate / polystyrene macromonomer copolymer, acrylic acid / benzyl acrylate / polymethyl methacrylate macromonomer copolymer Polymer, acrylic acid / 2-hydroxyethyl acrylate / benzyl acrylate / polystyrene macromonomer copolymer, acrylic acid / 2-hydroxyethyl acrylate / benzyl acetate Rate / polymethyl methacrylate macromonomer copolymer, acrylic acid / benzyl methacrylate copolymer, acrylic acid / styrene / methyl methacrylate copolymer, acrylic acid / styrene / benzyl methacrylate copolymer, acrylic acid / methyl methacrylate / polystyrene macro Monomer copolymer, acrylic acid / methyl methacrylate / polymethyl methacrylate macromonomer copolymer, acrylic acid / benzyl methacrylate / polystyrene macromonomer copolymer, acrylic acid / benzyl methacrylate / polymethyl methacrylate macromonomer copolymer, acrylic acid / 2-hydroxyethyl methacrylate / benzyl methacrylate / polystyrene macromonomer copolymer, acrylic acid / 2-hydroxyethyl methacrylate DOO / benzyl methacrylate / polymethyl methacrylate macromonomer copolymers of acrylic acid copolymers such as;

  Methacrylic acid / benzyl acrylate copolymer, methacrylic acid / styrene / methyl acrylate copolymer, methacrylic acid / styrene / benzyl acrylate copolymer, methacrylic acid / methyl acrylate / polystyrene macromonomer copolymer, methacrylic acid / methyl acrylate / Polymethyl methacrylate macromonomer copolymer, methacrylic acid / benzyl acrylate / polystyrene macromonomer copolymer, methacrylic acid / benzyl acrylate / polymethyl methacrylate macromonomer copolymer, methacrylic acid / 2-hydroxyethyl acrylate / benzyl acrylate / polystyrene Macromonomer copolymer, methacrylic acid / 2-hydroxyethyl acrylate / benzyl acrylate / polymethyl methacrylate Mer copolymer, methacrylic acid / benzyl methacrylate copolymer, methacrylic acid / styrene / methyl methacrylate copolymer, methacrylic acid / styrene / benzyl methacrylate copolymer, methacrylic acid / methyl methacrylate / polystyrene macromonomer copolymer, methacryl Acid / methyl methacrylate / polymethyl methacrylate macromonomer copolymer, methacrylic acid / benzyl methacrylate / polystyrene macromonomer copolymer, methacrylic acid / benzyl methacrylate / polymethyl methacrylate macromonomer copolymer, methacrylic acid / 2-hydroxyethyl methacrylate / Benzyl methacrylate / polystyrene macromonomer copolymer, methacrylic acid / 2-hydroxyethyl methacrylate / benzyl methacrylate DOO / polymethyl methacrylate macromonomer copolymers methacrylic acid copolymers such as and the like.

  Among these carboxyl group-containing copolymers (B1), methacrylic acid / benzyl methacrylate copolymer, methacrylic acid / styrene / methyl methacrylate copolymer, methacrylic acid / styrene / benzyl methacrylate copolymer, methacrylic acid / Methyl methacrylate / polystyrene macromonomer copolymer, methacrylic acid / methyl methacrylate / polymethyl methacrylate macromonomer copolymer, methacrylic acid / benzyl methacrylate / polystyrene macromonomer copolymer, methacrylic acid / benzyl methacrylate / polymethyl methacrylate macromonomer copolymer Polymer, methacrylic acid / 2-hydroxyethyl methacrylate / benzyl methacrylate / polystyrene macromonomer copolymer, methacrylic acid / 2-hydroxy Chill methacrylate / benzyl methacrylate / polymethyl methacrylate macromonomer copolymers. The copolymerization ratio of the carboxyl group-containing unsaturated monomer in the carboxyl group-containing copolymer (B1) is usually 5 to 50% by weight, preferably 10 to 40% by weight. In this invention, a carboxyl group-containing copolymer (B1) can be used individually or in mixture of 2 or more types.

  Another preferable binder resin that can be used in the present invention is an N-substituted maleimide and another copolymerizable ethylenically unsaturated monomer (hereinafter referred to as “other unsaturated monomer (b2)”). And a copolymer (hereinafter referred to as “N-position-substituted maleimide copolymer (B2)”). Examples of the N-substituent in the N-substituted maleimide include a (Cyclo) alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, an aralkyl group having 7 to 30 carbon atoms, and these groups. Among these N-substituents, aryl groups having 6 to 20 carbon atoms and substituted derivatives thereof are preferable.

  Specific examples of the N-substituted maleimide include N-methylmaleimide, N-ethylmaleimide, Nn-propylmaleimide, Ni-propylmaleimide, Nn-butylmaleimide, Nt-butylmaleimide, N N- (cyclo) alkyl-substituted maleimides such as -n-pentylmaleimide, Nn-hexylmaleimide, N-cyclohexylmaleimide, N-4-methylcyclohexylmaleimide, N-4-chlorocyclohexylmaleimide, and their substitution Derivatives: N-phenylmaleimide, N-o-hydroxyphenylmaleimide, Nm-hydroxyphenylmaleimide, Np-hydroxyphenylmaleimide, N-o-methylphenylmaleimide, Nm-methylphenylmaleimide, N- p-methylphenylmaleimide, N N-aryl-substituted maleimides such as o-methoxyphenylmaleimide, Nm-methoxyphenylmaleimide, Np-methoxyphenylmaleimide, Np-chlorophenylmaleimide, and substituted derivatives thereof; N-benzylmaleimide; N-phenethylmaleimide, N-o-hydroxybenzylmaleimide, Nm-hydroxybenzylmaleimide, Np-hydroxybenzylmaleimide, N-o-methylbenzylmaleimide, Nm-methylbenzylmaleimide, Np-methyl N-aralkyl-substituted maleimides such as benzylmaleimide, N-o-methoxybenzylmaleimide, Nm-methoxybenzylmaleimide, Np-methoxybenzylmaleimide, Np-chlorobenzylmaleimide, and substituted derivatives thereof etc It can be mentioned.

  Among these N-substituted maleimides, N-cyclohexylmaleimide, N-phenylmaleimide, N-o-hydroxyphenylmaleimide, Nm-hydroxyphenylmaleimide, Np-hydroxyphenylmaleimide, N-o-methylphenyl Maleimide, Nm-methylphenylmaleimide, Np-methylphenylmaleimide, N-o-methoxyphenylmaleimide, Nm-methoxyphenylmaleimide, and Np-methoxyphenylmaleimide are preferable. The N-substituted maleimides can be used alone or in admixture of two or more.

  The other unsaturated monomer (b2) is not limited as long as it can be copolymerized with the N-substituted maleimide, but one or more of the carboxyl group-containing unsaturated monomers and the other A monomer mixture containing at least one unsaturated monomer (b1) is preferred.

  As the N-substituted maleimide copolymer (B2), a copolymer of N-phenylmaleimide is preferable, and N-phenylmaleimide, a carboxyl group-containing unsaturated monomer, and other unsaturated monomers ( b1), in particular (1) N-phenylmaleimide, (2) acrylic acid and / or methacrylic acid, (3) styrene, (4) methyl acrylate, methyl methacrylate, 2 -Copolymerization with at least one selected from the group consisting of hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, allyl acrylate, allyl methacrylate, benzyl acrylate, benzyl methacrylate, phenyl acrylate, phenyl methacrylate, polystyrene macromonomer and polymethyl methacrylate macromonomer Coalescence is preferable.

  Specific examples of preferable N-position-substituted maleimide copolymer (B2) include N-phenylmaleimide / methacrylic acid / styrene / allyl acrylate copolymer, N-phenylmaleimide / methacrylic acid / styrene / allyl methacrylate copolymer. N-phenylmaleimide / methacrylic acid / styrene / benzyl methacrylate copolymer, N-phenylmaleimide / methacrylic acid / styrene / phenyl methacrylate copolymer, N-phenylmaleimide / methacrylic acid / styrene / benzyl methacrylate / polystyrene macromonomer copolymer Polymer, N-phenylmaleimide / methacrylic acid / styrene / benzyl methacrylate / polymethyl methacrylate macromonomer copolymer, N-phenylmaleimide / methacrylic acid / styrene / phenylmeta Relate / polystyrene macromonomer copolymer, N-phenylmaleimide / methacrylic acid / styrene / phenyl methacrylate / polymethyl methacrylate macromonomer copolymer, N-phenylmaleimide / methacrylic acid / styrene / 2-hydroxyethyl methacrylate / benzyl methacrylate / Polystyrene macromonomer copolymer, N-phenylmaleimide / methacrylic acid / styrene / 2-hydroxyethyl methacrylate / benzyl methacrylate / polymethyl methacrylate macromonomer copolymer, N-phenylmaleimide / methacrylic acid / styrene / 2-hydroxyethyl methacrylate / Phenyl methacrylate / polystyrene macromonomer copolymer, N-phenylmaleimide / methacrylic acid / styrene / 2-hi It can be exemplified b methacrylate / phenyl methacrylate / polymethyl methacrylate macromonomer copolymers.

  The copolymerization ratio of the N-substituted maleimide in the N-substituted maleimide copolymer (B2) is usually 5 to 50% by weight, preferably 10 to 40% by weight. When the N-substituted maleimide copolymer is a copolymer of an N-substituted maleimide, a carboxyl group-containing unsaturated monomer, and another unsaturated monomer (b1), the carboxyl group-containing unsaturated The copolymerization ratio of the monomer is usually 5 to 50% by weight, preferably 10 to 40% by weight, and the copolymerization ratio of the other unsaturated monomer (b1) is usually 10 to 90% by weight. , Preferably 20 to 80% by weight. In the present invention, the N-position-substituted maleimide copolymer (B2) can be used alone or in admixture of two or more.

  The polystyrene-converted weight average molecular weight (hereinafter simply referred to as “weight average molecular weight”) measured by gel permeation chromatography (GPC; elution solvent tetrahydrofuran) of each resin component constituting the binder resin used in the present invention is preferably. 3,000 to 300,000, particularly preferably 5,000 to 100,000. The ratio of the binder resin used in the present invention is usually 10 to 1,000 parts by weight, preferably 20 to 500 parts by weight with respect to 100 parts by weight of the (A) pigment. In this case, when the usage ratio of the binder resin is less than 10 parts by weight, for example, the discharge property of the color filter ink and the hardness of the formed pixels tend to decrease. In addition, since the colorant concentration decreases, it may be difficult to achieve the target color density as a thin film.

  In general, the color filter ink of the present invention preferably further includes an organic solvent in addition to the pigment and binder resin described above, and may optionally include other components. Of the organic solvents, water-soluble organic solvents are preferred.

  Examples of the water-soluble organic solvent include C1-C4 alkyl alcohols such as ethanol, methanol, butanol, propanol, and isopropanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, and ethylene glycol monomethyl ether. Acetate, 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 ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-iso-propyl ether, propylene glycol mono-n -Glycol ethers such as butyl ether or dipropylene glycol mono-n-butyl ether Alternatively, there may be mentioned formamide, acetamide, dimethyl sulfoxide, sorbitol, sorbitan, acetin, diacetin, triacetin, or sulfolane and the like.

  In addition to the water-soluble organic solvent, 1,2-alkyldiol is preferably used. Specifically, as the alkyl ether of polyhydric alcohol, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, ethylene 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 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, etc. It is done. Specific examples of the 1,2-alkyldiol include 1,2-pentanediol and 1,2-hexanediol. In addition to these, linear carbonization such as 1,3-propanediol, 1,4-butanediol 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, etc. It may be appropriately selected from hydrogen diols.

  In the color filter ink of the present invention, a high boiling point organic solvent can be used as the organic solvent for the purpose of preventing clogging of the color filter ink.

  Specific examples 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 monomethyl ether, dipropylene glycol monoethyl glycol, dipropylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol, triethylene glycol monomethyl ether, tetraethylene glycol, triethylene glycol, diethylene glycol monobutyl ether , Diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, tripropylene glycol Polyethylene glycol having 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, Examples thereof include glycerin, mesoerythritol, and pentaerythritol.

  These can be used alone or as a mixture of two or more. Accordingly, it is possible to provide an ink for a color filter that maintains fluidity and redispersibility for a long time even when left in an open state (in a state where it is exposed to air at room temperature). In addition, nozzle clogging is less likely to occur during inkjet discharge or restarting after discharge interruption, and high discharge stability is obtained.

  The content of these organic solvents is preferably about 10 to 50% by weight, more preferably 10 to 30% by weight, based on the total weight of the color filter ink.

  Furthermore, examples of the organic solvent include polar solvents such as 2-pyrrolidone, N-methylpyrrolidone, ε-caprolactam, dimethyl sulfoxide, sulfolane, morpholine, N-ethylmorpholine, 1,3-dimethyl-2-imidazolidinone. One or more of these may be selected and used. The addition of these polar solvents has an effect on dispersibility and can improve the ejection stability of ink. The content of these polar solvents is preferably 0.1% by weight to 20% by weight and more preferably 1% by weight to 10% by weight with respect to the total weight of the color filter ink.

  The ejection by the ink jet method is suitably performed by mounting the ink for an ink jet color filter according to the embodiment of the present invention on a known ink jet printer apparatus and ejecting the ink to a filter substrate. Thereby, the discharge stability of the ink from the inkjet head can be made excellent.

  The color filter ink in the invention can contain a polyfunctional monomer having two or more polymerizable unsaturated bonds as a crosslinkable monomer component. Examples of the polyfunctional monomer include diacrylates or dimethacrylates of alkylene glycols such as ethylene glycol and propylene glycol; diacrylates or dimethacrylates of polyalkylene glycols such as polyethylene glycol and polypropylene glycol; Polyacrylates or polymethacrylates of trihydric or higher polyhydric alcohols such as methylolpropane, pentaerythritol, dipentaerythritol or the like, or modified carboxylic acids thereof; polyester, epoxy resin, urethane resin, alkyd resin, silicone resin, spirane resin, etc. Oligoacrylates or oligomethacrylates of: both ends hydroxypolybutadiene, both ends hydroxypolyisoprene, both ends hydroxypoly Diacrylates or dimethacrylates and the both ends hydroxylated polymer of caprolactone such as, tris (2-acryloyloxyethyl) phosphate, may be mentioned tris (2-methacryloyloxyethyl) phosphate and the like.

  Among these polyfunctional monomers, polyacrylates or polymethacrylates of trihydric or higher polyhydric alcohols or modified carboxylic acids thereof, specifically, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, Pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, the following formula (1):

In particular, trimethylolpropane triacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate are preferable in terms of high pixel strength and excellent pixel surface smoothness. The said polyfunctional monomer can be used individually or in mixture of 2 or more types. The usage-amount of the polyfunctional monomer in this invention is 500 parts weight or less normally with respect to 100 weight part of binder resins, Preferably it is 20-300 weight part. In this case, when the usage ratio of the polyfunctional monomer exceeds 500 parts by weight, the ink ejection performance tends to be lowered.

  In the present invention, a part of the polyfunctional monomer can be replaced with a monofunctional monomer having one polymerizable unsaturated bond. Specific examples of such monofunctional monomers include methoxyethylene glycol acrylate, methoxydiethylene glycol acrylate, methoxytriethylene glycol acrylate, methoxyethylene glycol methacrylate, methoxydiethylene glycol methacrylate, methoxytriethylene glycol methacrylate, methoxypropylene glycol acrylate, Methoxydipropylene glycol acrylate, methoxypropylene glycol methacrylate, methoxydipropylene glycol methacrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxy-3-phenoxypropyl methacrylate, succinic acid 2-acryloyloxyethyl, succinic acid 2- Methacryloyloxyethyl, ω-carbo Sipolycaprolactone monoacrylate, ω-carboxypolycaprolactone monomethacrylate, and the like can be mentioned, and further commercially available products include M-5300, M-5400 (trade names, manufactured by Toagosei Co., Ltd.), and the like. it can. These monofunctional monomers can be used alone or in admixture of two or more. The proportion of the monofunctional monomer used is usually 90% by weight or less, preferably 50% by weight or less, based on the total of the polyfunctional monomer and the monofunctional monomer.

  The color filter ink in the present invention can impart radiation curability by blending a photopolymerization initiator. Here, the radiation means a substance including visible light, ultraviolet light, far ultraviolet light, X-rays, electron beams and the like.

  The color filter ink in the present invention preferably has a contact angle of 45 degrees or more, more preferably 50 degrees or more with the partition formed from the color filter partition forming resin composition. By having such a contact angle, there is no ink color mixture between the pixel arrays, and the amount of ink that can be ejected to the light transmission region can be increased so as to ensure a sufficient color density of the pixel pattern. It becomes.

[Production method of color filter]
Next, a method for producing a color filter by the ink jet method using the color filter ink according to an embodiment of the present invention (hereinafter simply referred to as “color filter production method”) will be described. FIG. 2 is a vertical cross-sectional view of a main part illustrating a liquid crystal display device having a color filter manufactured by the method for manufacturing a color filter in the present invention. As shown in the figure, the color filter 1 basically includes a substrate 101, partition walls 102, pixel patterns 20 (for example, red), 21 (for example, green) and 22 (for example, blue) for each color, and a protective layer 103 that covers the pixel pattern. These components are light-transmitting except for the partition wall 102, but the partition wall 102 may be light-transmitting or light-blocking. Further, in the liquid crystal display device 6, the polarizing plate 201 is disposed on the outer surface side of the substrate 101, and the common electrode 202, the alignment film 203, the liquid crystal layer 204, the alignment film 205, the pixel electrode 206, the substrate are disposed on the protective layer 103. 207 and polarizing plate 208 are basically laminated.
In the present color filter, the ink described above is used for forming the pixel when the pixel pattern 20 shows a red color.

  As the material of the substrate 101, an appropriate light-transmitting material can be adopted as long as it has heat resistance to heating conditions in the color filter manufacturing process and has a certain level of mechanical strength, Examples thereof include glass, silicon, polycarbonate, polyester, aromatic polyamide, polyamideimide, polyimide, norbornene-based ring-opening polymer and hydrogenated products thereof. In addition, the substrate made of these materials may be subjected to appropriate pretreatment such as chemical treatment with a silane coupling agent, plasma treatment, ion plating, sputtering, gas phase reaction method, vacuum deposition, etc., if desired. You can also. These materials can also be used for the substrate 207, but the materials may be changed between the two substrates depending on circumstances.

  The partition wall 102 is formed of a suitable resin composition for forming a partition wall, and the surface of the substrate 101 is partitioned in a lattice shape in the figure, and the region partitioned by the partition wall 102 has a light transmission region that transmits light. There is no. However, the partition shape by the partition 102 may be changed as desired. Examples of the resin composition used for forming the partition wall 102 include (i) a radiation-sensitive resin composition that contains a binder resin, a polyfunctional monomer, a photopolymerization initiator, and the like and is cured by irradiation with radiation. And (ii) a binder resin, a compound that generates an acid upon irradiation with radiation, a crosslinkable compound that can be cross-linked by the action of an acid generated upon irradiation with radiation, and the like. Things can be used. These partition wall-forming radiation-sensitive resin compositions are usually prepared as a liquid composition by mixing a solvent when used, and this solvent may be a high-boiling solvent or a low-boiling solvent. As the radiation-sensitive resin composition for forming a partition wall in the present invention, as described in JP-A-10-86456, (a) hexafluoropropylene, unsaturated carboxylic acid (anhydride), and other copolymers A copolymer with a possible ethylenically unsaturated monomer, (b) a compound capable of generating an acid upon irradiation with radiation, (c) a crosslinkable compound capable of crosslinking by the action of an acid generated upon irradiation with radiation, (d A composition containing a fluorine-containing organic compound other than the component (a) and a solvent capable of dissolving the components (a) to (d) is preferable.

  The pixel pattern 20 is formed from a color filter resin composition containing, for example, a red colorant, the pixel pattern 21 is formed from, for example, a color filter resin composition containing a green colorant, and the pixel pattern 22 is For example, it is formed from the resin composition for color filters containing a blue coloring agent, and these pixel patterns are formed by the inkjet system mentioned later. The total number of pixel patterns defined by the partition walls 102 is obtained by multiplying the number of pixel patterns of each color in the liquid crystal display device by the number of primary colors (the three primary colors of red, green, and blue in the figure). For example, in the case of a VGA type liquid crystal display device used for an information terminal such as a personal computer, the number of pixel patterns for each color is 640 columns × 480 rows, so that a total of (640 × 480 × 3) pixel patterns are used. Will be composed. The arrangement pitch of the pixel pattern is, for example, 100 μm. In the figure, the number of pixel patterns is reduced to facilitate understanding.

  The material of the protective layer 103 may be a normal material used for the formation of a protective layer for a color filter, but it can be used by a light or heat action or a light that can use a general-purpose exposure apparatus, a baking furnace, or a hot plate. What is hardened | cured by combined use with a heat | fever is preferable, and it becomes possible to aim at the cost reduction of an installation, and space saving.

  Further, the common electrode 202 can be formed by using a material having optical transparency and conductivity, for example, ITO (Indium Tin Oxide) and processing it by a conventional method. The alignment films 203 and 205 can be formed, for example, by subjecting a film formed from an appropriate liquid crystal aligning agent to a rubbing treatment or the like, and has an action of aligning liquid crystal molecules in a certain direction. The liquid crystal layer 204 is composed of polarized liquid crystal molecules, and is configured such that the orientation direction of the liquid crystal molecules can be controlled by applying a voltage. The pixel electrode 206 is arranged corresponding to each pixel pattern of the color filter 1 and connected to the output terminal of the driving means (see FIG. 4). The pixel electrode 206 is also made of a material having optical transparency and conductivity, and the same material as that of the common electrode 202 can be used as the material. Good. As the driving means, for example, TFT (thin film transistor), TFD (thin film diode) or the like can be used. Polarizing plates 201 and 208 are attached to the outside of the substrates 101 and 207. These polarizing plates transmit only light in a specific polarization state out of backlight light irradiated from behind the liquid crystal display device 6. The two polarizing plates are arranged so that the polarization direction of the light after passing through them is “shifted” by, for example, the polarization rotation angle that the liquid crystal molecules give to the light when no voltage is applied to the liquid crystal layer 204. .

Next, the manufacturing process of the color filter will be described with reference to FIGS. Here, only the manufacturing process of the color filter 1 in the liquid crystal display device 6 will be described. A known technique can be applied to manufacture the remaining components of the liquid crystal display device 6. FIG. 1 is a longitudinal sectional view of a main part illustrating the manufacturing process of the color filter 1, showing a cut surface corresponding to the AA arrow view of FIG. 3, and FIG. 3 is a plan view of the color filter 1. is there. First, the barrier rib-forming radiation-sensitive resin composition is applied as a solution to the substrate 101 and then pre-baked (PB) to evaporate the solvent to form a coating film. The PB conditions in this case are, for example, a heating temperature of about 50 to 150 ° C. and a heating time of about 30 to 600 seconds. Thereafter, this coating film is irradiated with radiation through a photomask and subjected to post-exposure baking (PEB), and then developed with an alkaline developer to dissolve and remove the unirradiated portions of the coating film. As a result, as shown in FIG. 1A, a plurality of light transmission regions 105 that transmit light on the surface of the substrate 101 are arranged on the surface of the substrate 101, in which partition patterns of a predetermined shape partitioned by the partition walls 102 are arranged according to a predetermined arrangement. A formed substrate is obtained. The PEB conditions in this case are, for example, a heating temperature of about 50 to 150 ° C., a heating time of about 30 to 600 seconds, and a radiation irradiation condition of, for example, about 1 to 500 mJ / cm ² . The developing condition is, for example, about 10 to 300 seconds. As the developing method, for example, a liquid piling method, a dipping method, a vibration dipping method, or the like can be employed. Further, post-baking may be performed after development, and the conditions are, for example, a heating temperature of about 150 to 280 ° C. and a heating time of about 3 minutes to 2 hours.

Next, as shown in FIG. 1B, the ink for an inkjet color filter is ejected from the inkjet head 10 to each light transmission region 105 so that the upper surface of the ink is raised from the upper end of the partition wall 102. The ink storage layers 21, 22,... Are formed in the respective light transmission regions 105. Reference numeral 20 exemplifies a state in the middle of ink ejection. In this case, the ink ejection speed is, for example, about 0.01 to 100 m / sec. Thereafter, as shown in FIG. 1C, the ink forming each reservoir layer is subjected to a heat treatment to evaporate the solvent, thereby drying the ink to obtain pixel patterns 20, 21, 22,. .. form. Note that the volume of each reservoir is reduced by such processing. The heat treatment in this case is performed using, for example, a heater, and is performed by heating the whole to a predetermined temperature (for example, about 50 degrees). Thereafter, in some cases, after irradiation with radiation, in order to completely dry and crosslink the resin composition, heating at a predetermined temperature (for example, about 150 to 280 ° C.) for a predetermined time (for example, about 3 minutes to 2 hours) is performed. Do. In this case, the radiation irradiation condition is, for example, about 1 to 500 mJ / cm ² . When forming the pixel patterns 20, 21, 22,..., A red, green, or blue resin composition is sequentially used, for example, so that a pixel array of the three primary colors red, green, and blue is disposed on the substrate 101. be able to.

  Thereafter, as shown in FIG. 1D, a protective layer 103 is formed by using an appropriate resin so as to cover the formed pixel patterns and to flatten the surface of the color filter. Furthermore, the common electrode 202 is formed on the protective layer 103 by using a material having light permeability and conductivity (for example, ITO) by a method such as sputtering or vapor deposition. In the case of forming a pattern on the common electrode 202, the common electrode 202 is etched in accordance with the pattern shape of other components such as the pixel electrode 206. The color filter 1 can be manufactured through the above steps. Next, as shown in FIG. 1E, an alignment film 203, a liquid crystal layer 204, and an alignment film 205 are sequentially formed between the color filter 1 and the substrate 207 on which the pixel electrode 206 is separately disposed, and both outer surfaces thereof are formed. Then, the polarizing plates 201 and 208 are attached to the liquid crystal display device 6.

  When the partition wall forming radiation-sensitive resin composition is applied to the substrate 101, an appropriate coating method such as spin coating, cast coating, roll coating, or the like can be employed. The coating thickness is usually 0.1 to 10 μm, preferably 0.5 to 3.0 μm, as the film thickness after PB. As the radiation used when forming the partition wall 102 and the pixel patterns 20, 21, 22,..., Visible light, ultraviolet light, far ultraviolet light, X-rays, electron beams, and the like can be used. Radiation in the range of 190-450 nm is preferred. Examples of the alkaline developer used for forming the partition wall 102 include sodium carbonate, sodium hydroxide, potassium hydroxide, sodium silicon, sodium metasilicon, ammonia water, ethylamine, n-propylamine, diethylamine, Di-n-propylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline, pyrrole, piperidine, 1,8-diazabicyclo [5.4.0]- An aqueous solution such as 7-undecene and 1,5-diazabicyclo [4.3.0] -5-nonene is preferable. For example, an appropriate amount of a water-soluble organic solvent such as methanol or ethanol, a surfactant, or the like can be added to the alkaline developer. In addition, after development with an alkaline developer, it is usually washed with water.

  Next, FIG. 4 illustrates an outline of a color filter manufacturing apparatus used in the color filter manufacturing method of the present invention. The color filter manufacturing apparatus includes a control device 2 that controls the inkjet head 10, motors 3 and 4, a position sensor 5, and the like. The ink jet head 10 ejects the supplied color filter ink from the nozzle, and the form thereof is not particularly limited, and a known ink jet method may be used. In the present invention, the color filter ink is used. Therefore, a piezo jet type which does not cause heat to act on the resin composition is preferable so as not to damage the material. The piezoelectric jet type inkjet head 10 is provided with N piezoelectric elements 40 (N is an arbitrary number) for discharging color filter ink. Further, the piezoelectric element 40 is configured so that driving and non-driving can be individually controlled.

  FIG. 5 illustrates a partially cutaway view of the main part of the inkjet head 10. The ink jet head 10 mainly includes a pressure chamber substrate 11, a vibration plate 12 and a nozzle plate 13, and the vibration plate 12 is provided on one surface of the pressure chamber substrate 11. Provided on the other surface. The pressure chamber substrate 11 is formed with a pressure chamber 14, a side wall 15, a reservoir 16, a supply port 17, and the like by etching a silicon substrate, for example, and volume change occurs in the pressure chamber 14 due to deformation of the diaphragm 12. As described above, the piezoelectric elements 40 provided on the diaphragm 12 and the pressure chambers 14 are aligned. The diaphragm 12 is an elastic film made of ceramics or the like, and is provided with the piezoelectric elements 40 arranged so as to be deformed by the distortion of the piezoelectric elements 40. Further, the diaphragm 12 is provided with an ink tank port 18 so that the color filter ink stored in an ink tank (not shown) can be supplied into the pressure chamber substrate 11, and is supplied into the pressure chamber substrate 11. The color filter ink flows through the path of the reservoir 16 → the supply ports 17 → the pressure chambers 14. The piezoelectric element 40 is configured by sandwiching a piezoelectric ceramic crystal between electrodes. The nozzle plate 13 is provided with nozzles 19 for ejecting color filter ink, and each nozzle 19 corresponds to each pressure chamber 16. The ink jet heads 10 are provided only for the types of color filter inks, and actually, for example, the red, green and blue ink jet heads 10 are used. However, only one inkjet head 10 is shown here for easy understanding.

  In such an ink jet head 10, only the piezoelectric element 40 to which a voltage is applied to the drive circuit is distorted, the diaphragm 12 is deformed, and pressure is applied to the pressure chamber 14 corresponding to the piezoelectric element. The color filter ink is ejected from the nozzle 19. Since the piezoelectric element 40 to which no voltage is applied is not distorted, the ink in the corresponding pressure chamber 14 is not ejected. Therefore, one set of the piezoelectric element 40, the pressure chamber 14, and the nozzle 19 constitutes one operating unit.

  Furthermore, FIG. 6 illustrates a plan view of the filter elements on the substrate 101 on which the nozzles 19 in the inkjet head 10 are arranged and the partition wall 102 that is the source of the color filter 1 is formed. Assuming that N nozzle numbers are hn (n is a number from 1 to N), the position Nn (xn, yn) of each nozzle 19 is specified by the relative coordinate x2 axis and the y2 axis as shown in the figure. It is like that. The smallest pixel element partitioned by the grid of the partition wall 102 is called a filter element, and for example, a window having a width of about 300 μm in the x1 axis (horizontal) direction and a length of about 100 μm in the y1 axis (vertical) direction is formed. In the substrate on which the partition wall is formed, the position Wm (xm, ym) of each filter element (m is a number from 1 to the maximum number of filter elements) is specified by the relative coordinate x1 axis and the y1 axis. ing. The pitch of each nozzle 19 is set to an integral multiple of the pitch in the x1 axis direction. For example, when 60 nozzles 19 are arranged in the inkjet head 10 and three drops of the color filter resin composition are ejected to one filter element, when the inkjet head 10 is operated at a driving frequency of 14.4 kHz, about 900,000 pixels are obtained. In the 10 type VGA color filter, the resin composition can be stored at 900,000 pixels × 3 drops / (14400 times / second × 60) = about 3 seconds. However, since it is necessary to consider the moving time of the inkjet head 10, the resin composition can actually be stored in all the filter elements within one minute.

  Such a method for producing a color filter is very advantageous industrially because the production process is simple and the cost is low. The color filter manufactured by the above-described color filter manufacturing method is extremely useful as, for example, a color liquid crystal display device, a color image pickup tube element, a color sensor, and the like as an additive color mixing type and a subtractive color mixing type.

  The color filter ink of the present invention can be applied to a color resist for photolithography, an ink for an ink jet method, or the like as a color material for a color filter. In particular, the color filter ink of the present invention is preferably used for ejection by an inkjet method.

  Further, according to the present invention, dispersion of fluorescent pigments in field emission displays (FEDs), surface field displays (SEDs), plasma displays (PDPs), etc., and conductive polymers in PEDOTs used in organic EL and organic TFTs, etc. It can also be applied to the dispersion of

  According to the present invention, there is provided a liquid crystal display device in which a display side substrate and a liquid crystal drive side substrate are opposed to each other, and liquid crystal is sealed between the two, and the display side substrate includes the color filter described above or A display device such as a liquid crystal display device, which is a color filter manufactured by a method for manufacturing a color filter, can be provided.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples. Unless otherwise specified, parts are parts by weight.

(Pigment dispersion composition)
As the pigment dispersion, one containing the following pigment was used.
Average particle size (50% volume average particle size)
Dispersion 1 (C.I. Pigment Red 254) 45 nm
Dispersion 2 (CI Pigment Red 177) ... 40 nm
Dispersion 3 (C.I. Pigment Yellow 139) 55 nm
Dispersion 4 (C.I. Pigment Yellow 150) ... 40 nm
Dispersion 5 (CI Pigment Yellow 180) ... 40 nm
Dispersion 6 (C.I. Pigment Yellow 180) 70 nm

  The compositions of the dispersions 1 to 6 are as shown in the following Table 1 (unit: wt%).

(Preparation of dispersion)
For dispersions 1-5, after mixing at a ratio in the dispersion composition table and stirring for 1 hour with a high-speed disper, this mixture was placed in a wet pulverizer filled with 80% zirconia beads having a diameter of 0.1 mm, Dispersed for 5 hours.
On the other hand, the dispersion 6 was mixed at a ratio in the dispersion composition table and stirred for 1 hour with a high-speed disper, and then the mixture was put in a wet pulverizer filled with 80% zirconia beads having a diameter of 0.2 mm. Dispersed for 4 hours.

(Preparation of ink)
Using the obtained dispersions 1 to 6, a red (R) pixel color filter ink was prepared by a generally known preparation method so as to have the composition shown in the following ink composition table.

(Color reproducibility / color tone: CIE standard color system / Yxy color system)
The color filter ink of the present invention contains at least CI pigment red 254, CI pigment red 177, and CI pigment yellow 180, and thus achieves a specific color (good color reproducibility), has high luminance, and has a contrast. In addition, it is possible to realize a high film, good ink storage stability, and good ink jet suitability and reliability. The film here refers to a film after drying the inkjet ink, or a film after curing when the binder component is curable.
Specifically, when the ink according to the present invention is formed into a uniform film having an average film thickness of 1.5 to 2.5 μm, and the film is measured with a C light source, x in the XYZ color system of CIE It is possible to achieve 0.600 to 0.675, y is 0.315 to 0.355, luminance Y is 17.0 or more, and contrast is 3500 or more.
Here, the uniform film means a film having a film thickness difference of less than 0.1 μm. Moreover, the said uniform film | membrane can be produced as follows, for example. First, an inkjet ink is applied on a glass substrate by spin coating. Thereafter, the ink film is dried, pre-baked as necessary, and then cured by exposure and / or heating as appropriate to form a uniform film. The film thickness after drying and curing can be measured by, for example, a stylus type film thickness measuring device (for example, product name dektak 3030 manufactured by Nihon Beco).

(Color tone)
The chromaticity (NTSC ratio, color tone) when the liquid crystal display device displayed a red (R) single color was measured. A color luminance meter (BM-5 manufactured by Topcon Corporation) was used for the measurement of chromaticity. As a result, the NTSC ratio was 90% or more.
In this chromaticity measurement, a color luminance meter was placed in the normal direction with respect to the center of the display in the absence of incident light from the surroundings, and the observation distance was 50 cm.
The color reproduction range is determined by the color of light emitted from red, green, and blue pixels, and the chromaticity points in the CIE XYZ color system of each pixel are (x _R , y _R ), (x _G , y _G ), (X _B , y _B ), it is represented by the area of a triangle surrounded by these three points on the xy chromaticity diagram. That is, the larger the area of the triangle, the more vivid color image can be reproduced. The area of this triangle is usually the three primary colors defined by the US National Television System Committee (NTSC): red (0.67, 0.33), green (0.21, 0.71), blue ( 0.14, 0.08), which is expressed as a ratio (unit%, hereinafter abbreviated as “NTSC ratio”) with respect to the area of the triangle. This value is about 40 to 50% for general notebook personal computers, 50 to 60% for desktop personal computer monitors, and about 70% for current liquid crystal TVs.
In recent years, there has been a growing demand for color liquid crystal display elements that can further enhance the color reproducibility of liquid crystal display elements and can express more vivid color images. Specifically, a high color purity display having an NTSC ratio of 80% or more is desired.

(contrast)
In the present invention, the contrast means the ratio of the luminance transmitted when two polarizing plates are combined so as to be orthogonal or parallel and sandwich the color filter (luminance when the polarizing plates are parallel / luminance when the polarizing plates are orthogonal) ) As an indicator. The contrast in the present invention is a value when measured as follows.

  Regarding the configuration of a measurement sample for contrast measurement, the configuration of luminance measurement in contrast measurement, and a specific measurement method, the description in paragraphs [0119] to [0121] of Japanese Patent Application Laid-Open No. 2007-124202 can be referred to.

<Dischargeability test>
3 to FIG. 6 installed in a chamber (thermal chamber), using the color filter ink set of each of the examples and comparative examples, at 25 ° C. and 35% RH. Then, the Y ink constituting the color filter ink set was discharged by continuously operating the droplet discharge device for 72 hours.
The nozzle clogging rate ([(number of clogged nozzles) / (total number of nozzles)] × 100) obtained after continuous operation is found and the nozzles are clogged. With respect to the above, it was examined whether or not clogging can be eliminated by a cleaning member made of a plastic material. The results were evaluated according to the following four criteria.
A: No nozzle clogging occurs.
B: The occurrence rate of nozzle clogging is less than 0.5% (excluding zero), and clogging can be eliminated by cleaning.
C: The occurrence rate of nozzle clogging is 0.5% or more and less than 1.0%, and clogging can be eliminated by cleaning.
D: The occurrence rate of nozzle clogging is 1.0% or more, or clogging cannot be eliminated by cleaning.

<Ink storage stability test>
The yellow color filter inks (Y inks) of the examples and comparative examples were left to stand in an environment of 55 ° C. for 40 days, then visually observed and evaluated according to the following five-stage criteria.
A: No change from before heating is observed.
B: Almost no aggregation or sedimentation of pigment particles is observed.
C: Slight aggregation / precipitation of pigment particles is observed.
D: Aggregation / sedimentation of pigment particles is clearly observed.
E: Aggregation / sedimentation of pigment particles is noticeable.

  The above evaluation results are shown below.

  The present invention is a color filter ink having excellent color reproducibility, brightness and contrast, excellent ink storage stability such as thermal stability, ink jet stability such as printing stability (inkjet ejection stability), and excellent reliability. In addition, the present invention has industrial applicability as a color filter using the same, a manufacturing method thereof, and a display device.

DESCRIPTION OF SYMBOLS 1 Color filter, 2 Control apparatus, 3 Motor, 4 Motor, 5 Position sensor, 6 Liquid crystal display device, 10 Inkjet head, 11 Pressure chamber board, 12 Vibrating plate, 13 Nozzle plate, 14 Pressure chamber, 15 Side wall, 16 Reservoir 17 supply port, 18 ink tank port, 19 nozzle, 20 pixel pattern, 21 pixel pattern, 22 pixel pattern, 40 piezoelectric element, 101 substrate, 102 partition, 103 protective layer, 105 light transmission region, 201 polarizing plate, 202 common Electrode, 203 alignment film, 204 liquid crystal layer, 205 alignment film, 206 pixel electrode, 207 substrate, 208 polarizing plate.

Claims (9)

A color filter ink comprising at least a pigment as a colorant and a binder resin,
The pigment is C.I. I. Pigment red 254, C.I. I. Pigment red 177, and C.I. I. An ink for color filter containing CI Pigment Yellow 180.   C. above. I. Pigment red 254, C.I. I. Pigment red 177, and C.I. I. The color filter ink according to claim 1, wherein the pigment yellow 180 has a weight ratio of 1 to 10: 1 to 4: 1.   The color filter ink according to claim 1, wherein a particle diameter of the pigment is 50 nm or less.   The color filter ink according to claim 1, wherein the binder resin is a thermosetting resin.   The color filter ink according to claim 1, further comprising a water-soluble organic solvent.   The color filter ink according to any one of claims 1 to 5, which is used for ejection by an inkjet method.   A color filter having a pixel pattern formed by an ink jet method using the color filter ink according to claim 1.   A method for producing a color filter by an ink jet method using the color filter ink according to claim 1, wherein an ink jet head is provided in each light transmission region that transmits light of a transparent substrate on which a partition wall is previously formed. Discharging the ink from the ink and storing the ink in each light transmission region partitioned by the partition; drying the ink stored in each light transmission region to form a pixel pattern; and And a step of forming a protective layer so as to cover the color filter.   A liquid crystal display device in which a display side substrate and a liquid crystal driving side substrate are opposed to each other, and liquid crystal is sealed between the two, wherein the display side substrate is the color filter according to claim 7 or claim 8. A liquid crystal display device, wherein the liquid crystal display device is a color filter manufactured by the method for manufacturing a color filter.