JP2001240780A - Red color resist ink and color filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a red color resist ink which can give a high level of lightness and chroma when used in color filters for liquid crystal displays. SOLUTION: In the red color resist ink obtained by dispersing a red pigment into a photosensitive resin composition, (D) a diketopyrrolopyrrole pigment and (E) a diketopyrrolopyrrole-sulfonic acid derivative or (A) a diketopyrrolopyrrole pigment whose surface has been treated with a diketopyrrolopyrrole-sulfonic acid derivative is used as the pigment component, and (B) a graft polymer obtained by reacting (a) a poly(lower alkyleneimine) or (b) a polyallylamine with (i) a polyester having a free carboxylic group, (ii) a polyamide or (iii) a polyesteramide to form an amide or a salt is used as the dispersing agent for dispersing this pigment component, and (C) a sulfonic acid derivative of an organic pigment is used as the crystal growth inhibitor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel red color resist ink used for a color filter for a liquid crystal display (hereinafter, also referred to as a CF for an LCD) and a CF for an LCD using the same.

[0002]

2. Description of the Related Art Hitherto, a composition for coloring a high-molecular organic material using diketopyrrolopyrrole as a red pigment has been known.
It has been disclosed that it can be used as a flash paste and preparation, and is suitable for printing inks, sizing colors, binder colors and coating materials (for example, JP-A-8-20731 and JP-A-8-20731).
27391).

[0003]

However, a red color resist ink is prepared using a dispersion of a diketopyrrolopyrrole pigment prepared according to the above-mentioned conventional formulation, and a color filter for a liquid crystal display is manufactured using the same. There is a problem that a high level of color saturation required for recent high-quality LCDs cannot be achieved. This is because the conventional diketopyrrolopyrrole has a large primary particle size and is hardly dispersible. Also, since diketopyrrolopyrrole has high crystal growth at high temperatures of 250 ° C or higher, in color filter applications exposed to high temperatures of 250 ° C or higher in the ITO sputtering process, color growth is achieved by crystal growth of the diketopyrrolopyrrole pigment. Crystals may be precipitated on the filter surface and cause haze, which is a problem.

An object of the present invention is to provide a red color resist ink which does not have the above-mentioned problems and provides a high level of color saturation when used in a CF for LCD.

[0005]

DISCLOSURE OF THE INVENTION The present inventors have developed diketopyrrolopyrrole into 4,4'-diamino-1,1'-bianthraquinone, which has been used as a red pigment for red color resist inks. In comparison, the spectral transmission curves 550 to 60
Focusing on the characteristic that the rising slope appearing near 0 nm is large, and using a red color resist ink to which this diketopyrrolopyrrole is applied as a red pigment, the overlapping area with the color matching function y (λ) is large. That is, it is possible to obtain a CF for LCD in which the brightness Y value is greatly improved from the conventional one, and further, by using the atomized product of diketopyrrolopyrrole as the red pigment, the increasing tendency of the Y value is further accelerated. The research was foreseen to begin. However, diketopyrrolopyrrole encounters the problem that dispersibility and dispersion stability are inferior to those of conventional pigments, and the problem that crystal growth at high temperatures may cause haze on the color filter surface. It was a hindrance to development. Thus, the present inventors
The present inventors have studied the dispersion conditions of the diketopyrrolopyrrole pigment, and have found the pigment dispersion conditions that are difficult to disperse when dispersing the pigment and that can suppress the crystal growth when the color filter is exposed to a high temperature, thereby completing the present invention.

That is, the present invention relates to a surface-treated diketopyrrolopyrrole pigment (A) in a red color resist ink obtained by dispersing a red pigment in a photosensitive resin composition, the surface being treated with a diketopyrrolopyrrolesulfonic acid derivative. But,
(A) Poly (lower alkylene imine) or (b) polyallylamine, (a) polyester having a free carboxylic acid group, (b) polyamide having a free carboxylic acid group or (c) free carboxylic acid group A red color resist ink characterized by being dispersed by using a graft polymer (B) obtained by reacting one or more selected from polyester amides to form an amide or a salt as a dispersant. . Further, the present invention provides a red color resist ink obtained by dispersing a red pigment in a photosensitive resin composition, wherein the diketopyrrolopyrrole pigment (D) is a diketopyrrolopyrrolesulfonic acid derivative (E) and the graft polymer (D). A red color resist ink characterized by being dispersed using B) as a dispersant. Further, the present invention is a color filter produced using the above-mentioned red color resist ink.

The red color resist ink contains a graft polymer (B) as a dispersant and a sulfonic acid derivative (C) of an organic pigment other than diketopyrrolopyrrole as a crystal growth inhibitor. The sulfonic acid derivative (C) of the organic pigment is preferably a benzidine yellow sulfonic acid derivative (C-1) or a 4,4′-diamino-1,1′-bianthraquinone sulfonic acid derivative (C- 2)
Are preferred. In addition, surface-treated diketopyrrolopyrrole pigment (A) or diketopyrrolopyrrole pigment (D)
And when the total amount of the organic pigment sulfonic acid derivative (C) is 100 parts by weight, the compounding ratio of the organic pigment sulfonic acid derivative (C) is advantageously in the range of 3 to 7 parts by weight, The blending ratio of the graft polymer (B) is advantageously in the range of 30 to 45 parts by weight, and the specific surface area of the surface-treated diketopyrrolopyrrole pigment (A) or the diketopyrrolopyrrole pigment (D) is preferably , 90 m ² / g or more.

Hereinafter, the present invention will be described in detail. The surface-treated diketopyrrolopyrrole pigment (A) and diketopyrrolopyrrole pigment (D) used in the present invention can be produced, for example, as follows. First, the diketopyrrolopyrrole pigment (D) can be synthesized by reacting p-chlorobenzonitrile with bromoacetate in the presence of zinc powder. Next, the surface-treated diketopyrrolopyrrole pigment (A) is obtained by adding diketopyrrolopyrrole pigment (D) to concentrated sulfuric acid,
Dissolved in fuming sulfuric acid, chlorosulfonic acid or a mixture thereof, heated to 80 to 90 ° C. to perform a sulfonation reaction, and then filtered and washed a suspension obtained by diluting with a large amount of water, followed by washing with water, The obtained filter cake is dried to obtain a diketopyrrolopyrrole sulfonic acid derivative, and then the diketopyrrolopyrrole and the diketopyrrolopyrrole sulfonic acid derivative are co-dissolved in concentrated sulfuric acid as a solvent. It is then co-precipitated, taken out as a water-containing cake by filtration, dried and pulverized to obtain diketopyrrolopyrrole whose diketopyrrolopyrrole has been surface-treated with a diketopyrrolopyrrolesulfonic acid derivative. However, the present invention is not limited to the above manufacturing method.

Here, the diketopyrrolopyrrole sulfonic acid derivative is represented by the following general formula (1)

Embedded image (Where X represents hydrogen or halogen, and m and n represent m
+ N = 1 to 4).

The mechanism by which the surface-treated diketopyrrolopyrrole (A) is more excellent in dispersibility and dispersion stability than ordinary diketopyrrolopyrrole can be estimated as follows.
That is, since the diketopyrrolopyrrole sulfonic acid derivative used for the surface treatment has the same molecular skeleton as diketopyrrolopyrrole, when the mixed sulfuric acid solution is put into water and co-precipitated, the diketopyrrolopyrrole sulfonic acid derivative is obtained. It is believed that the acid derivative adsorbs and coalesces on the diketopyrrolopyrrole surface to produce a surface treated state. At this time, the hydrophilic sulfonic acid group appears on the combined surface and increases the negative surface potential of the diketopyrrolopyrrole pigment surface, contributing to an increase in pigment dispersibility and dispersion stability due to electrostatic repulsion, and The diketopyrrolopyrrole sulfonic acid derivative increases the negative potential and increases the adsorptivity and adsorptive power of a polymer dispersant having a cationic anchor portion such as an amino group described later, and causes steric repulsion by the dispersant. It is considered that the compound also functions as a dispersing aid that further increases the force and further increases the pigment dispersibility and dispersion stability.

The surface-treated diketopyrrolopyrrole (A) and diketopyrrolopyrrole (D) used in the present invention
It is preferable to use an atomized product having a specific surface area of 90 m ² / g or more from the viewpoint of further improving the brightness Y value. This atomized product is referred to as a so-called flushing method in which the hydrous cake is mixed with a vehicle and the vigorous stirring is continued to transfer the derivative surface-treated diketopyrrolopyrrole from the aqueous phase to the vehicle phase. It can be obtained by applying the method. Examples of the vehicle used herein include a surfactant, a polymer dispersant, an organic solvent solution of rosin and a rosin derivative, and the like. The derivative surface-treated diketopyrrolopyrrole is atomized by preventing reaggregation. Goods can be obtained. Further, as a method for producing the atomized product, a salt milling method in which a surface-treated diketopyrrolopyrrole is crushed in a mill in the presence of salt can also be mentioned. The method for producing the atomized product is not particularly limited.

Further, the surface-treated diketopyrrolopyrrole (A) and diketopyrrolopyrrole (D) used in the present invention.
It is preferable to use those produced from diketopyrrolopyrrole and its sulfonic acid derivative from which impurities have been removed by washing and purifying with an organic solvent, from the viewpoint of improving the problem of crystal precipitation and discoloration caused by impurities. Here, examples of the impurities include organic substances, such as 4-chlorobenzonitrile, which are residues of raw materials used for producing diketopyrrolopyrrole.

Accordingly, the organic solvent used for washing diketopyrrolopyrrole is not particularly limited as long as it dissolves the above impurities and does not dissolve diketopyrrolopyrrole. Group solvents and ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone.

The red color resist ink of the present invention is a surface-treated diketopyrrolopyrrole pigment (A) which is a red pigment.
Alternatively, it comprises a diketopyrrolopyrrole pigment (D), a photosensitive resin composition, and a dispersant. The pigment dispersion using the surface-treated diketopyrrolopyrrole pigment (A) itself has the dispersibility due to the electrostatic repulsion described above, but for the purpose of further imparting a steric repulsion effect, a graft polymer ( B) is used as a dispersant.

The graft polymer (B) as a dispersant is a dispersant having a cationic group portion adsorbed on a pigment and serving as an anchor, and a polymer chain portion imparting dispersibility by a steric repulsion effect. . The graft polymer (B) comprises (a) poly (lower alkyleneimine) or (b) polyallylamine, (a) a polyester having a free carboxylic acid group, (b) a polyamide having a free carboxylic acid group, and (C) A graft polymer obtained by reacting one or more selected from polyesteramides having a free carboxylic acid group to form an amide or a salt. The method for producing such a graft polymer and the like are known methods (Japanese Patent Publication No. 63-30057 and Japanese Patent Application Laid-Open No.
169821). (A)
As to (b) or (a) to (c), only one type may be used, or one or more types may be used in two or more types.

Here, (a) and (b) are cationic group portions which serve as anchors, and (a) to (c) are polymer chain portions which impart dispersibility by a steric repulsion effect. Accordingly, the amount of amino groups (a) and (b) and (a) to (b)
The molecular weight of (c) affects the dispersibility and dispersion stability of the pigment. The amine value of the dispersant can be used as an index of the dispersant performance, and the amine value of the cationic polymer dispersant used in the present invention is preferably in the range of 5 to 60 [KOHmg / g]. The range of ４０40 [KOHmg / g] is more preferable. A decrease in the amine value indicates that the amount of amino groups in (a) to (b) is reduced or that the molecular weight of (a) to (c) is increased. Works disadvantageously, but works favorably for the steric repulsion effect. Conversely, an increase in the amine value has the opposite effect, that is, the above-mentioned optimum range exists for the amine value of the cationic polymer dispersant. Commercially available cationic polymer dispersants applicable to the present invention include, for example, Solsperse (trade name, manufactured by Avecia).
24000GR, Solsperse 24000SC, manufactured by Ajinomoto Fine-Techno Co., Inc .: Trade name: Azispar PB-821.

In the red color resist ink of the present invention, a sulfone of an organic pigment other than diketopyrrolopyrrole is used as a crystal growth inhibitor for the surface-treated diketopyrrolopyrrole pigment (A) or diketopyrrolopyrrole pigment (D). It is preferable to add the acid derivative (C). The sulfonic acid derivative (C) of the organic pigment is not particularly limited as long as it is a sulfonic acid derivative of an organic pigment having a molecular structure other than diketopyrrolopyrrole, but is preferably red or yellow in terms of hue. Yellow sulfonic acid derivative (C-
1) and 4,4′-diamino-1,1′-bianthraquinonesulfonic acid derivative (C-2).

Benzidine yellow sulfonic acid derivative (C-
1) is to produce by diazobenzidine tetraazotization, coupling with acetoacetarylide to obtain benzidine yellow, then sulfonation in the same manner as the diketopyrrolopyrrole sulfonic acid derivative described above. Can be.

The benzidine yellow sulfonic acid derivative (C-1) is represented by the following general formula (2)

Embedded image (Wherein, R ₁ and R ₂ represent hydrogen or chlorine, X represents hydrogen, a methyl group or methoxy group, Y represents hydrogen, a methyl group or chlorine, and Z represents hydrogen or a methoxy group, respectively) be able to.

The diaminobianthraquinone sulfonic acid derivative (C-2) is prepared by condensing 1-amino-4-chloro-2-sulfonic acid and desulfonating the resulting diaminobianthraquinone into concentrated sulfuric acid, fuming sulfuric acid, Dissolve in chlorosulfonic acid or a mixture thereof, room temperature to 80 to 90 ° C
, And then the suspension obtained by diluting with a large amount of water is filtered, washed with water, and the obtained filter cake is dried and pulverized to produce a product. There is no commercially available diaminobianthraquinone sulfonic acid derivative (C-2).

The diaminobianthraquinonesulfonic acid derivative (C-2) is represented by the following general formula (3)

Embedded image (Where m and n are m + n = 1 to 4).

The mechanism of why the sulfonic acid derivative (C) of an organic pigment other than diketopyrrolopyrrole exhibits a crystal growth-inhibiting effect on the diketopyrrolopyrrole-based pigment (A) or (D) is unknown, Even when a sulfonic acid derivative of diketopyrrolopyrrole itself is blended, it does not show a crystal growth inhibiting action. Therefore, sulfonic acid derivative of an organic pigment having a different molecular structure from diketopyrrolopyrrole (C) is (A)
It is considered that by adsorbing on the surface of (D), the characteristics of (A) or (D) change, and crystal growth is suppressed.

The color resist ink of the present invention comprises (1)
Those having a surface-treated diketopyrrolopyrrole pigment (A) surface-treated with a diketopyrrolopyrrolesulfonic acid derivative and a graft polymer (B) as a dispersant as essential components;
(2) a diketopyrrolopyrrole pigment (D), a diketopyrrolopyrrolesulfonic acid derivative (E) and a graft polymer (B) as a dispersant as essential components; and (3) a surface-treated diketopyrrolopyrrole pigment. (A) and a diketopyrrolopyrrole pigment (D), and those containing a diketopyrrolopyrrolesulfonic acid derivative (E) and a graft polymer (B) as a dispersant as essential components. The color resist ink (2) uses a diketopyrrolopyrrole sulfonic acid derivative (E) as another dispersant instead of not treating the surface of the diketopyrrolopyrrole pigment. The color resist ink (3) uses both a surface-treated diketopyrrolopyrrole pigment (A) and a diketopyrrolopyrrole pigment (D) as pigment components. In addition, it is preferable that a sulfonic acid derivative (C) of an organic pigment other than diketopyrrolopyrrole be used as a crystal growth inhibitor in any of the color resist inks.

The mixing ratio of each component is as follows: surface-treated diketopyrrolopyrrole pigment (A), graft polymer (B), sulfonic acid derivative of organic pigment other than diketopyrrolopyrrole (C), diketopyrrolopyrrole pigment (D ) And the amount of diketopyrrolopyrrolesulfonic acid derivative (E) (parts by weight) expressed in (A), (B), (C), (D) and (E), respectively, should be within the following ranges: Is advantageous. When (A) and (B) are contained and the total amount of (A) is 100 parts by weight, (B) is 30
~ 45 parts by weight. Contains (A), (B) and (C), (A) + (C)
(B) is 30 to 45 parts by weight, when the total amount of
(C) 3 to 7 parts by weight. Containing (B), (D) and (E), (D)
When the total amount of + (E) is 100 parts by weight, (B) is 30 to 45 parts by weight. (B), (C), (D), (E), (D) + (E) +
When the total amount of (C) is 100 parts by weight, (B) is 30 to 45 parts by weight, and (C) is 3 to 7 parts by weight. (A), (B), (C), (D),
(E), and the total amount of (A) + (D) + (E) + (C) is 100
(B) 30 to 45 parts by weight, (C) 3 to 7 parts by weight
Parts by weight. The ratio of (D) to (E) is preferably in the range of 5 to 30 parts by weight when the total amount of (D) + (E) is 100 parts by weight.

The blending amount of the graft polymer (B) as a dispersant is a total of 1 and a total of the pigment component and the dispersant component excluding (B).
The amount is preferably 30 to 45 parts by weight with respect to 00 parts by weight, and when the amount is less than this range, the pigment dispersion tends to be unsuitable because it has a high viscosity and a large viscosity with time.
On the other hand, if the compounding amount is larger than this range, the pattern may be lost in the alkali developing step at the time of producing the color filter, which is likely to be unsuitable.

The compounding amount of the sulfonic acid derivative (C) of an organic pigment other than diketopyrrolopyrrole, which is a crystal growth inhibitor, is 3 to 7 parts by weight based on 100 parts by weight of the pigment component and the dispersant component in total. It is preferably within the range. If the compounding amount is less than this range, the effect of suppressing the crystal growth at the time of exposure of the color filter to high temperatures is insufficient, and the color filter tends to be unsuitable. On the other hand, if the compounding amount is larger than this range, the dispersibility becomes poor and aggregated particles are generated on the coated surface of the resist ink, which is likely to be unsuitable. Here, (A) and (D) are calculated as pigment components, (C) and (E) are calculated as dispersant components and the like, but (B) is excluded from the calculation. Also,
(C) is a crystal growth inhibitor, but also acts as a dispersing aid for (B), and is therefore sometimes referred to as a dispersing aid.
Similarly, although (E) is a dispersant, it also acts as a dispersing aid or crystal growth inhibitor on (B), and thus may be referred to as a dispersing aid or crystal growth inhibitor.

In the red color resist ink of the present invention, the method for dispersing (A) the surface-treated diketopyrrolopyrrole pigment or (D) the diketopyrrolopyrrole pigment, which is a red pigment, in a photosensitive resin is as follows. A red pigment dispersion is prepared by dispersing the pigment in an organic solvent in which a graft polymer (B) as a dispersant is dissolved, and the red pigment dispersion is prepared from a composition containing a photosensitive resin (preferably, a photopolymerization initiator is removed). And a method in which the pigment is directly dispersed in a composition containing a photosensitive resin, and the former method is preferable from the viewpoint of the stability of the color resist ink.

As the organic solvent used above, esters and the like from the viewpoint of excellent dispersibility of the pigment and dispersant,
Ketones, polyhydric alcohol derivatives, nitrogen-containing solvents and the like can be used, for example, esters include ethyl acetate and butyl acetate, and ketones include cyclohexanone and ethyl butyl ketone. Examples include ethylene glycol monoethyl ether acetate and propylene glycol monomethyl ether acetate, and examples of the nitrogen-containing solvent include dimethylformamide.

The surface-treated diketopyrrolopyrrole pigment (A) or diketopyrrolopyrrole pigment (D) used in the present invention may be co-dispersed with a yellow pigment from the viewpoint of toning. By blending the yellow pigment, the spectral transmission curve shifts to a lower wavelength side, which advantageously works to improve the brightness Y value.

As such a yellow pigment, CI pigment numbers PY-83 and PY-139 can be used.

Surface-treated diketopyrrolopyrrole pigment (A)
Alternatively, when dispersing the diketopyrrolopyrrole pigment (D) into an ink or a red pigment dispersion composition, the pigment, the graft polymer (B) of the dispersant and the organic solvent, or a photosensitive resin and the like are first used in a roll mill. After kneading the mixture, an organic solvent is added and the mixture is further dispersed using a bead mill to produce an ink or a red pigment dispersion composition, from the viewpoint of improving dispersibility such as eliminating coarse particles. In particular, when the pigment derivative used as a dispersing aid or a crystal growth inhibitor is a coarse particle, kneading while finely pulverizing is required, so that roll mill kneading is essential.

As this roll mill, a two-roll mill,
A three-roll mill or the like can be used.
This roll mill is preferred. The operating conditions of the three-roll mill are as follows: the front roll rotation speed is 50 to 200 rpm, and the rotation ratio of the front roll: the middle roll: the rear roll is 1.0: 1.5: 5.0.
~ 1.0: 3.0: 8.0. By performing roll mill kneading, dispersion stability is further improved.

For the subsequent bead mill dispersion, a disk rotating type bead mill, an annular type bead mill or the like can be used.
The operating conditions when using a disk rotating type bead mill are as follows.
Bead filling rate 80% or more, disk peripheral speed 10-20m /
Preferably, it is seconds. An example of such a commercially available bead mill is a disc rotating type manufactured by WAB:
DYNO-MILL, manufactured by Inoue Manufacturing Co., Ltd .: trade name Mighty Mill, EIGER: trade name MOTOR MILL, etc. In the case of an annular type, EIRICH: trade name DCP-disulfonic acid UPERFLOW, manufactured by WAB: Product name DYNO-MILL ECM, manufactured by Mitsubishi Heavy Industries, Ltd .: Product name Diamond Fine Mill,
Inoue Seisakusho Co., Ltd .: Trade name: Spike mill and the like.

The red color resist ink of the present invention is obtained by dispersing a surface-treated diketopyrrolopyrrole (A) or a diketopyrrolopyrrole pigment (D) as a red pigment in a transparent resin. It is a photopolymerizable resin or a photosensitive resin composed of a monomer or oligomer. Also,
The photosensitive resin composition referred to in the present invention usually contains a photopolymerization initiator and an organic solvent in addition to the above resin or monomer or oligomer, as long as it becomes a resin in a cured state, and in an uncured state. Includes those consisting only of non-resinous components.

Examples of such a photosensitive resin, monomer or oligomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and ethylene glycol di (meth) acrylate. , Diethylene glycol di (meth) acrylate, triethylene glycol (meth) acrylate, tetraethylene glycol di (meth) acrylate, tetramethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) Acrylate, pentaerythritol di (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, glycerol Meth) acrylate, bisphenol A epoxy (meth) acrylate, bisphenol F type epoxy (meth) acrylate, (meth) acrylic acid esters such as bisphenol fluorene type epoxy di (meth) acrylate. These photopolymerizable monomers and oligomers may be used alone or in combination of two or more.

Examples of the photopolymerization initiator include acetophenones such as acetophenone, 2,2'-diethoxyacetophenone, p-dimethylacetophenone, p-tert-butylacetophenone, benzophenone, 2-chlorobenzophenone, p, p Benzophenones such as'-bisdimethylaminobenzophenone; benzoin ethers such as benzoin methyl ether, benzoin isopropyl ether and benzoin butyl ether; 2-methyl-1- [4- (methylthio) phenyl] -2-monforinopropanone- 1,2-benzyl-2-dimethylamino-1- (4-monofoliophenyl)-
Α-Aminoalkylphenones such as butanone-1, and sulfur compounds such as benzyldimethyl ketal, thioxanthone, 2-chlorothioxanthone, and 2,4-diethylthioxanthone. These photopolymerization initiators may be used alone or in combination of two or more.

Examples of the organic solvent include ketones such as methyl isobutyl ketone, diisobutyl ketone and cyclohexanone, and cellosolves such as methyl cellosolve, ethyl cellosolve, ethyl cellosolve acetate, and propylene glycol monomethyl ether acetate. These organic solvents may be used alone or in combination of two or more.

Surface-treated diketopyrrolopyrrole pigment (A)
Alternatively, when the diketopyrrolopyrrole pigment (D) is prepared as a red pigment dispersion in advance, the amount thereof and the mixing ratio of the photosensitive resin composition are appropriately selected according to the required exposure sensitivity and the degree of developability. , Usually the weight ratio of solids, the former: the latter =
The ratio is preferably from 5:95 to 30:70. The ink thus obtained is suitable as a CF red ink, and the CF obtained by using this ink has a film obtained by curing this in a pixel. In addition, as a method of producing CF using this ink, a known method can be adopted.

[0039]

Next, the present invention will be described more specifically with reference to examples and comparative examples. Pigments used in Examples and Comparative Examples,
Abbreviations of the pigment derivative, dispersant, crystal growth inhibitor and organic solvent are shown below.

<Red pigment: components (A) and (D)> (A) -1: A diketopyrrolopyrrole represented by the following formula was surface-treated with a diketopyrrolopyrrolesulfonic acid derivative represented by the following formula. a specific surface area of 93.8 m ² / g atomization process diketopyrrolopyrrole pigment (D) -1: atomization treated pigment of the diketopyrrolopyrrole having a specific surface area represented by the following formula 93.8 m ² / g

Embedded image

Embedded image

<Dispersant: Component (B)> (B) -A: A graft polymer having an amine value of 7.7 obtained by reacting a poly (allylamine) described in JP-A-9-169821 with a polyester having a free carboxylic acid group. (Ajinomoto Fine Techno Co., Ltd .: trade name: Azispar PB-821) 50.0% by weight solution (B) -B: Poly (ethylene imine) described in JP-B-63-30057 which has free carboxylic acid groups (B) -C: a polyepoxy compound described in JP-A-9-87537 having a carboxyl group at one end having a 50.0% by weight solution of a graft polymer having an amine value of 30.6 (Avecia: trade name: Solsperse 24000GR) reacted with 49.9% by weight solution of a graft polymer having an amine value of 35.5 reacted with a linear polymer and an organic amino compound having one secondary amino group (manufactured by Ajinomoto Fine Techno Co., Ltd .: Azispar PB-711) (B) -D: JP 60-166318 A 47.0 wt% solution of polyisocyanate compound to hydrocarbon compounds and hydrocarbon compounds polyurethane compound of amine value 20.1 is reacted with an amino group having an alcoholic hydroxyl group (BYK
Chemie: disperbyk-163) (B) -E: amine value obtained by reacting a polyisocyanate compound with a hydrocarbon compound having an amino group with a polymer of an acrylate having an alcoholic hydroxyl group described in JP-A-1-164429. 49.1% by weight solution of acrylate polymer of 29.1 (manufactured by EFKA Chemical B.V .: EFKA-46)

<Dispersant, Crystal Growth Inhibitor, Dispersing Aid:
(E) and (C) components> (E) -1: Sulfonic acid derivative of diketopyrrolopyrrole represented by the above formula (C) -BY: Benzidine yellow sulfonic acid derivative represented by the following formula

Embedded image (C) -AQ: a sulfonic acid derivative of 4,4′-diamino-1,1′-bianthraquinone represented by the following formula

Embedded image

<Organic solvent> S-1: propylene glycol monomethyl ether acetate S-2: diethylene glycol dimethyl ether

The conditions for evaluating the properties of the prepared pigment dispersion and color resist ink coating film are shown below. <Evaluation of Properties of Pigment Dispersion><Viscosity> After the dispersion, the red pigment dispersion composition was allowed to stand at room temperature for 24 hours in a constant temperature water bath at 23 ° C. for 40 minutes. The viscosity was measured at a rotational speed of 60 rpm and at a temperature of 23 ° C. using a Tokimec product (brand name BL type) to obtain an initial viscosity. Next, the dispersion was placed in a hot air oven at 40 ° C. for one week, the viscosity was measured under the same conditions, and the change over time during storage at 40 ° C. was evaluated. <TI value (thixotropic index value)> Revolution 6
The value obtained by dividing the viscosity at rpm by the viscosity at 60 rpm was defined as the initial TI value. The smaller this value is, the closer to 1, the smaller the thixotropy (the larger the Newtonian fluidity), the better. Next, the dispersion was placed in a hot-air oven at 40 ° C. for one week, and then a TI value was measured under the same conditions to evaluate a temporal change in storage at 40 ° C.

<Average Particle Size> The average particle size is measured by diluting 0.003 g of the red pigment dispersion composition with 40 g of propylene glycol monomethyl ether acetate in an organic solvent and performing ultrasonic dispersion in an ultrasonic cleaner for 90 seconds. Samples were prepared and measured using a laser Doppler particle size distribution analyzer (trade name: ELS-800, manufactured by Otsuka Electronics Co., Ltd.).

<Evaluation of Properties of Color Resist Ink Coating Film><Coatability Observation (Presence or Absence of Center Navel)> The ink coating film was irradiated with a yellow lamp to observe the surface. Was evaluated. Generally, if the viscosity and TI value of the pigment dispersion used are low and the dispersibility and dispersion stability are good, the coatability is good.

<Microscopic Observation of Surface State (Presence or Absence of Agglomerated Particles or Crystal Precipitation)> The surface state of the ink coating film was observed using a reflection type polarizing microscope with a magnification of 400 times. The evaluation was made in three stages: possible (○), slightly acceptable but usable (△), remarkably acceptable and unusable (x), and evaluated in the initial state. Next, after the ink-coated plate was placed in a hot-air oven and exposed at 250 ° C. for 1 hour, the surface condition was observed under the same conditions as above, and a three-step evaluation was performed.

<Brightness Y value and chromaticity (x, y)> Chromaticity meter [manufactured by Tokyo Denshoku Co., Ltd .: trade name Color Analyzer TC-180]
0MK2). <Film thickness> It was represented by a value measured using a stylus type surface roughness meter (manufactured by Tokyo Seimitsu Co., Ltd.). <Pattern disappearance during alkali development> After the exposed ink coating was developed with a 0.4% aqueous sodium carbonate solution, the magnification of the photomask pattern line having a line width of 100 μm was determined as to whether or not the line disappeared due to elution. Evaluation was made by observation with a 100-fold reflection-type polarizing microscope. ○ does not disappear and × disappears.

Example 1 [Preparation of pigment dispersion and evaluation of properties] The composition shown in Table 1, namely, 187.0 g of pigment (A) -1, 112.2 g of dispersant (B) -A, 1130.8 g of organic solvent S-1 In a 2L plastic container, and then homomixer (Robomix, manufactured by Tokushu Kika Kogyo Co., Ltd.)
After mixing at 2000 rpm for 1 hour, a pigment was dispersed using a disk rotating bead mill (trade name: DYNO-MILL KDL-Special, manufactured by WAB), and the dispersant (B) compounding ratio was 30.0% by weight.
A pigment dispersion having a solid content of 17.0% by weight and a pigment etc. of 13.1% by weight was prepared.

Table 1 shows the blending amount (g), blending ratio and the like together with those of the other examples. Here, dispersant (B), crystal growth inhibitor
(C) and the mixing ratio of the dispersant (E), (A) + (D) + (C) +
(E) = Based on 100% by weight. Also, all the embodiments,
In Comparative Examples, etc., pigments and the like ((A)
+ (D) + (E)) / resin ((B) + resin) weight ratio is 0.49
And the solid content concentration was kept constant at 20.0% by weight.

The operating conditions of the bead mill were as follows. That is, the media beads have a zirconia material of 0.3 m.
mφ was used at a filling rate of 80%. The disk peripheral speed is 8.6 m / sec, the charging pressure is 0.5 bar and the dispersion time is 4
Time. The properties of this red pigment dispersion composition were evaluated according to the method described above. Table 1 shows the results of the characteristic evaluation.

The average particle size was 134 nm, and the atomization was sufficiently achieved. The initial viscosity is 6.40 mPa · s, 40 ° C-
One week later, it stopped at 9.34 mPa · s, an increase of 2.94 points, and the initial value of the TI value was 1.08, and after one week at 40 ° C., it was 1.07, so the dispersion stability was good. there were.

[Preparation of Color Resist Ink Coating Film and Evaluation of Properties] Since the atomization state and dispersion stability of the pigment dispersion were good as described above, the color resist ink and its coating film were prepared, and the properties were evaluated. went. As a resin component, an epoxy acrylate resin solution having a fluorene skeleton [manufactured by Nippon Steel Chemical Co., Ltd .: trade name: V-259ME, solid content: 55.3]
%] 150.91 g, dipentaerythritol hexaacrylate 35.76 g, epoxy resin having a biphenyl skeleton (trade name: Epicoat YX-4000HK, manufactured by Yuka Shell Epoxy Co., Ltd.) 17.88 g, and a photopolymerization initiator component was used. As 2-methyl-1- [4- (methylthio) phenyl]-
3.58 g of 2-monforinopropane-1, 4,4'-bis-
1.93 g of diethylaminobenzophenone, 5.36 g of 2,4-trichloromethyl- (4′-methoxystyryl) -6-triazine, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone 1.79 g of -1 and 294.75 g of a fluorine-based surfactant (manufactured by Sumitomo 3M Co., Ltd .: trade name: Florard FC-430) in an amount of 0.12 g
Was dissolved in an organic solvent S-1 to prepare a photosensitive resin composition having a solid content concentration of 29.2%. Then, according to the composition shown in Table 1, 10.0 g of the photosensitive resin composition, 20.6 g of the pigment dispersion, 3.5 g of organic solvent S-1 and S-2.
8.5 g was stirred and mixed to prepare a red color resist ink.

This color resist ink was applied to a 5 inch square, 1 m thick film using a spin coater (Mikasa Co., Ltd.).
m on a blue glass plate. The rotation speed of the spin coater at this time was adjusted so that the ink film thickness was 1.5 μm (after post-baking), and the time was 10 seconds. next,
This ink-coated glass plate was pre-baked. The prebaking conditions were 80 ° C. for 3 minutes. Next, after placing a photomask on the glass plate coated with pre-baked ink, 300 mj /
A cm ² UV exposure was performed. This UV-irradiated ink-coated glass plate was alkali-developed with a 0.4% aqueous sodium carbonate solution for 25 seconds. The glass plate coated with the alkali developing ink was post-baked at 230 ° C. for 30 minutes to form an ink coating film as a model red color filter. Using the thus-prepared ink coating film as a sample, the color characteristics of the color resist ink were evaluated according to the method described above. Table 1 shows the results
Shown in

The ink coating film prepared using the color resist ink obtained in the present example has no coat having a dent in the center and has good coatability (○). In the initial state, no aggregated particles or crystal precipitation were observed, and the sample was usable (（). After exposure at 250 ° C. for 1 hour, no aggregated particles were observed, and crystal precipitation was slightly observed, but was within the usable range (△). The lightness Y value was an excellent value of 21.9, and there was no problem with the pattern disappearance resistance during alkali development (○).

Examples 2 to 6 [Preparation of pigment dispersion and evaluation of properties] Pigment dispersions were prepared in the same procedure as in Example 1 except that the composition was as shown in Table 1, and the properties were evaluated. Table 1 shows the results.
As in Example 1, the properties of the pigment dispersion were good. [Preparation of Color Resist Ink Coating Film and Evaluation of Properties] A color resist ink was prepared according to the formulation shown in Table 1, and a resist ink coating film was prepared in the same procedure as in Example 1 to evaluate the color characteristics. Table 1 also shows the evaluation results of the ink coating films. Example 1
Similarly, the properties of the ink coating film were good.

Example 7 [Preparation of pigment dispersion and evaluation of properties] The composition was as shown in Table 1, except that the crystal growth inhibitor was changed from (C) -BY to (C) -AQ. A pigment dispersion was prepared with substantially the same composition as in Example 5. However, since the (C) -AQ used was coarse, three-roll kneading was carried out for the purpose of this fine pulverization kneading, followed by bead mill dispersion. That is, pigment (A) -119
0.0 g, 10.0 g of the crystal growth inhibitor (C) -AQ, and 140.0 g of the dispersant (B) -A were mixed in a 2-L plastic container, and then roll-rolled with a three-roll mill (trade name: Inoue Seisakusho Co., Ltd .: C) -43 / 4 × 1
0). Here, the reason why the three-roll mill kneading was performed is to knead the fine particles while finely pulverizing the crystal growth inhibitor AQ-S. The operating condition of the three-roll mill is that the rotation speed of the front roll is 120 rpm, the rotation ratio of the front roll: the middle roll: the rear roll is 1.0: 2.6: 6.8, and the three-roll kneading is performed by passing through five passes. I got something. Next, 260.0 g of the three-roll kneaded material and an organic solvent
After mixing 457.4 g of S-1 in a 2 L plastic container, the mixture was stirred and mixed at 2,000 rpm for 1 hour using a homomixer (trade name: Robomix, manufactured by Tokushu Kika Kogyo Co., Ltd.). A bead mill dispersion was performed under operating conditions to prepare a pigment dispersion, and the properties were evaluated. The results are shown in Table 1. Similarly, it had good pigment dispersion properties.

[Preparation of Color Resist Ink Coating Film and Evaluation of Properties] A color resist ink was prepared according to the formulation shown in Table 1, and a resist ink coating film was prepared in the same procedure as in Example 1 to evaluate the color characteristics. Table 1 also shows the evaluation results of the ink coating films. Similarly, it was excellent in lightness, had no problem in resistance to pattern disappearance during alkali development, and did not show any agglomerated particles after exposure at 250 ° C. for 1 hour, showing very good results.

Examples 8 to 13 [Preparation of Pigment Dispersion and Evaluation of Properties] As shown in Table 1, the three-roll kneading was carried out under the same conditions as in Example 7 to obtain a kneaded product. Next, bead mill dispersion was performed under the same composition as shown in Table 1 and under the same operating conditions as in Example 1 to prepare a pigment dispersion, and its properties were evaluated. The results are shown in Table 1. Similarly, it had good pigment dispersion properties.

[Preparation of Color Resist Ink Coating Film and Evaluation of Properties] Since the properties of the pigment dispersion were good, a color resist ink was prepared according to the formulation shown in Table 1, and the resist ink was prepared in the same procedure as in Example 1. A coating film was prepared and the color characteristics were evaluated. Table 1 also shows the evaluation results of the ink coating films. As in Example 1, the properties of the ink coating film were good. Example 1
In Nos. 2 and 13, the lightness was good, the pattern disappearance resistance during alkali development was not a problem, and microscopic observation after exposure at 250 ° C. for 1 hour showed no crystal precipitation and very good (○) characteristics. .

[0061]

[Table 1]

Comparative Example 1 [Preparation of Pigment Dispersion and Evaluation of Properties] The composition was shown in Table 2. Under the same conditions as in Example 1, a pigment dispersion was prepared and its properties were evaluated. The results are shown in Table 2. The average particle size is 126 nm
However, the initial value was 492 although the atomization was achieved.
mPa · s, 818 mPa · s after one week at 40 ° C, TI value was initial value 6.50, and 6.87 after one week at 40 ° C, and the dispersion stability was extremely poor.

[Preparation of Color Resist Ink Coating Film and Evaluation of Characteristics] After preparing a color resist ink with the composition shown in Table 2, an ink coating film was prepared under the same conditions as in Example 1 and the characteristics were evaluated. The results are shown in Table 2. In the center of the ink coating film, a dark portion (snudge) is observed, and the coating property observation result is poor (x). Therefore, the film thickness-color characteristics (chromaticity, lightness)
Did not evaluate.

Comparative Examples 2-3 [Preparation of pigment dispersion and evaluation of properties] Under the same conditions as in Example 1, a pigment dispersion was prepared and its properties were evaluated. The results are shown in Table 2. Except for Comparative Example 3,
Although the average particle size is 149 nm or less and atomization can be achieved, the viscosity is the difference between the initial value and the value after one week at 40 ° C., TI
The difference between the initial value and the value after one week at 40 ° C. was large, and the dispersion stability was extremely poor. Comparative Example 3
The average particle size was 228 nm, atomization was not achieved, and the viscosity was 950 mPa · s as the initial value, and 1450 mPa · s after one week at 40 ° C.
s, TI value is initial value 6.84, 40 ° C-7.93 after one week,
The dispersion stability was extremely poor.

[Preparation of Color Resist Ink Coating Film and Characteristic Evaluation] After preparing a color resist ink with the composition shown in Table 2, an ink coating film was prepared under the same conditions as in Example 1 and the characteristics were evaluated. The results are shown in Table 2. In the center of the ink coating film, a dark portion (snudge) is observed, and the coating property observation result is poor (x). Therefore, the film thickness-color characteristics (chromaticity, lightness)
Did not evaluate.

Experimental Example 1, Example 14 [Preparation of Pigment Dispersion and Evaluation of Properties] The composition of the composition is shown in Table 2. Under the same conditions as in Example 1, a pigment dispersion was prepared and its properties were evaluated. The results are shown in Table 2. [Preparation of Color Resist Ink Coating Film and Characteristic Evaluation] After preparing a color resist ink with the composition shown in Table 2, an ink coating film was prepared under the same conditions as in Example 1 and the characteristics were evaluated.
The results are shown in Table 2. When the mixing ratio of the dispersant (B) is out of the preferable range, it is found that good properties may not be obtained in some cases.

Example 15 [Preparation of Pigment Dispersion and Evaluation of Properties] The composition was shown in Table 2. However, since (E) -1 is also a coarse particle, three-roll kneading was carried out in the same procedure as in Example 7 for the purpose of this fine pulverization and kneading, followed by bead mill dispersion. Table 2 shows the characteristic evaluation results. The average particle size was 123 nm, and atomization could be achieved. The initial viscosity is 8.69 mPa · s, 21.5 mPa after 1 week at 40 ° C.
A slight increase was observed in s, but within the allowable range, the TI value was 1.04 at the initial value, 1.00 after one week at 40 ° C., and the dispersion stability was almost good.

[Preparation of Color Resist Ink Coating Film and Evaluation of Characteristics] After preparing a color resist ink with the composition shown in Table 2, an ink coating film was prepared under the same conditions as in Example 5 and the characteristics were evaluated. Are shown in Table 2. There was no dark portion at the center of the ink film (navel), and the results of observation of coatability were good (O). The results of microscopic observation of the surface were good at the beginning, but a little after 250 ° C for 1 hour. Crystal precipitation (△)
Was observed.

Experimental Example 2 [Preparation of Pigment Dispersion and Evaluation of Properties] Table 2 shows the composition. That is, the compounding ratio of the crystal growth inhibitor (C) -BY was adjusted to 10.0.
A pigment dispersion was prepared under the same conditions as in Example 5 except that the content was increased to% by weight, and the results of property evaluation are shown in Table 2. The average particle size was 123 nm, and atomization could be achieved. The initial value was 8.69 mPa · s, a slight increase at 21.5 mPa · s after 1 week at 40 ° C was within the allowable range, but the TI value was 1.04 at the initial value and 1 week after 40 ° C. At 1.00, the dispersion stability was almost good.

[Preparation of Color Resist Ink Coating Film and Evaluation of Characteristics] After preparing a color resist ink with the composition shown in Table 2, an ink coating film was prepared under the same conditions as in Example 5 and the characteristics were evaluated. The results are shown in Table 2. There was no dark portion (skew) in the center of the ink coating film, and the coatability was good (O). However, the microscopic observation of the surface showed that the aggregated particles both at the initial stage and after exposure at 270 ° C for 1 hour were observed. The surface condition was recognized as poor (x). It can be seen that if the crystal growth inhibitor is added in excess of the preferred range, good properties may not be obtained.

Comparative Example 4 [Preparation of Pigment Dispersion and Evaluation of Properties] The composition was shown in Table 2. That is, a pigment dispersion was prepared under the same conditions as in Example 2 except that DPP-A was changed from DPP-A to DPP-B, and the property evaluation results are shown in Table 2. The average particle size was 165 nm, atomization was not achieved, and the viscosity was initial value 1126 mPa · s, 40 ° C.-1
After 2 weeks, it was as high as 2390 mPa · s, and the initial TI value was 6.91.
The value was as high as 8.74 after one week at 40 ° C., and the dispersion stability was extremely poor.

[Preparation of Color Resist Ink Coating Film and Evaluation of Properties] After preparing a color resist ink with the composition shown in Table 2, an ink coating film was prepared under the same conditions as in Example 2, and the properties were evaluated. The results are shown in Table 2. At the center of the ink coating film, a dark portion (navel) was observed, and the coating property observation result was poor (x). Therefore, evaluation of the film thickness-color characteristics was not performed.

Comparative Examples 5 to 7 [Preparation of Pigment Dispersion and Characteristic Evaluation] That is, the dispersant species (B) -A to (B) -C, (B) -D or (B)
A pigment dispersion was prepared under the same conditions as in Example 8 except that -E was used, and the results of property evaluation are shown in Table 2. The average particle size is
In Comparative Example 8, although slightly large, atomization was almost achieved at 131 to 231 nm, but the viscosity was initially 486 to 976 mPa.
・ S, high at 796 ~ 1511mPa ・ s after 1 week at 40 ℃,
The TI value was also an initial value of 6.38 to 6.90, and was as high as 6.84 to 8.13 after one week at 40 ° C., and the dispersion stability was extremely poor.

[Preparation of Color Resist Ink Coating Film and Evaluation of Properties] After preparing a color resist ink with the composition shown in Table 2, an ink coating film was prepared under the same conditions as in Example 8 and the characteristics were evaluated. The results are shown in Table 2. At the center of the ink coating film, a dark portion (navel) was observed, and the coating property observation result was poor (x). Therefore, evaluation of the film thickness-color characteristics was not performed.

[0075]

[Table 2]

[0076]

The red color resist ink of the present invention is
Since it has a high spectral transmittance and a high Y value, it is extremely useful in that it enables the production of a CF for LCD that requires high brightness and chroma. Further, the pigment dispersion composition used in the present invention,
In addition to color resist inks, they are also useful as paints requiring high gloss, writing inks requiring high transparency, ink jet printer inks, and printing inks.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) G03F 7/037 G03F 7/037 (72) Inventor Koichi Fujishiro 1 Tsukiji, Kisarazu-shi, Chiba Nippon Steel Chemical Co., Ltd. Material development center F term (reference) 2H025 AA02 AB13 AB20 CC11 CC20 2H048 BA45 BA47 BA48 BA57 4J039 AE08 AE09 AE13 BC05 BC06 BC33 BC36 BC40 BC50 BC54 BC65 BC68 BC74 BC77 BC79 BE01 BE22 BE33 EA05 EA15 EA33 GA17

Claims (16)

[Claims] 1. A red color resist ink obtained by dispersing a red pigment in a photosensitive resin composition, wherein a surface-treated diketopyrrolopyrrole pigment (A) surface-treated with a diketopyrrolopyrrolesulfonic acid derivative comprises (a) ) Poly (lower alkylene imine) or (b) polyallylamine,
1 selected from polyester having a free carboxylic acid group, (b) polyamide having a free carboxylic acid group, and (c) polyesteramide having a free carboxylic acid group
A red color resist ink characterized by being dispersed using a graft polymer (B) formed by reacting a kind or two or more kinds to form an amide or a salt as a dispersant. 2. The red color resist ink according to claim 1, wherein the blending amount of the graft polymer (B) as a dispersant is 30 to 45 parts by weight with respect to 100 parts by weight of the surface-treated diketopyrrolopyrrole pigment (A). . 3. A red color resist ink comprising a red pigment dispersed in a photosensitive resin composition, wherein the surface-treated diketopyrrolopyrrole pigment (A) is a graft polymer (B).
The red color resist ink according to claim 1, which is dispersed by using a sulfonic acid derivative (C) of an organic pigment other than diketopyrrolopyrrole as a crystal growth inhibitor. 4. The method according to claim 1, wherein the sulfonic acid derivative (C) of the organic pigment which is a crystal growth inhibitor is benzidine yellow sulfonic acid derivative (C-1) or 4,4′-diamino-1,1′-bianthraquinone sulfonic acid. The red color resist ink according to claim 3, which is a derivative (C-2). 5. The total amount of the surface-treated diketopyrrolopyrrole pigment (A) and the sulfonic acid derivative (C) of the organic pigment is 100
The compounding amount of the sulfonic acid derivative (C) of the organic pigment is in the range of 3 to 7 parts by weight and the compounding amount of the graft polymer (B) is in the range of 30 to 45 parts by weight.
Red color resist ink as described. 6. The red color resist ink according to claim 1, wherein the surface-treated diketopyrrolopyrrole pigment (A) is an atomized pigment having a specific surface area of 90 m ² / g or more. 7. A red color resist ink obtained by dispersing a red pigment in a photosensitive resin composition, wherein the diketopyrrolopyrrole pigment (D) is a diketopyrrolopyrrolesulfonic acid derivative (E), and (Lower alkyleneimine) or (b) polyallylamine, (a) polyester having a free carboxylic acid group, (b) polyamide having a free carboxylic acid group, and (c) polyesteramide having a free carboxylic acid group. A red color resist ink characterized by being dispersed using a graft polymer (B) obtained by reacting one or more selected ones to form an amide or a salt as a dispersant. 8. The blending amount of the graft polymer (B) is 30 to 45 parts by weight based on 100 parts by weight of the total amount of the diketopyrrolopyrrole pigment (D) and the diketopyrrolopyrrolesulfonic acid derivative (E). 7. The red color resist ink according to 7. 9. A red color resist ink obtained by dispersing a red pigment in a photosensitive resin composition, wherein the diketopyrrolopyrrole pigment (D) is a diketopyrrolopyrrolesulfonic acid derivative (E) and a graft polymer (B). To the dispersant,
The red color resist ink according to claim 7, which is dispersed using a sulfonic acid derivative (C) of an organic pigment other than diketopyrrolopyrrole as a crystal growth inhibitor. 10. A sulfonic acid derivative (C) of an organic pigment.
Is a benzidine yellow sulfonic acid derivative (C-1) or
The red color resist ink according to claim 9, which is a 4,4'-diamino-1,1'-bianthraquinonesulfonic acid derivative (C-2). 11. The total amount of the diketopyrrolopyrrole pigment (D), the diketopyrrolopyrrolesulfonic acid derivative (E) and the organic pigment sulfonic acid derivative (C) is defined as 100 parts by weight.
10. The red color resist according to claim 9, wherein the compounding amount of the sulfonic acid derivative (C) of the organic pigment is in the range of 3 to 7 parts by weight, and the compounding amount of the graft polymer (B) is in the range of 30 to 45 parts by weight. ink. 12. The red color resist ink according to claim 7, wherein the diketopyrrolopyrrole pigment (D) is a finely divided pigment having a specific surface area of 90 m ² / g or more. 13. The red color resist ink according to claim 7, further comprising a surface-treated diketopyrrolopyrrole pigment (A) which has been surface-treated with a diketopyrrolopyrrolesulfonic acid derivative. 14. A surface-treated diketopyrrolopyrrole pigment (A) or a diketopyrrolopyrrole pigment (D) and a diketopyrrolopyrrolesulfonic acid derivative (E) are dispersed using a graft polymer (B) as a dispersant. The method for producing a red color resist ink according to any one of claims 1 to 13, wherein a pigment dispersion is produced, and the pigment dispersion is dispersed in a photosensitive resin composition. 15. A pigment dispersion according to claim 14. 16. A color filter produced using the red color resist ink according to claim 1. Description: