WO2010137702A1 - Heat-curable ink-jet ink for color filter - Google Patents

Abstract

Provided is a heat-curable ink-jet ink for color filters which has excellent storage stability and curability, has excellent chemical resistance after heat curing, and attains satisfactory color reproducibility throughout the gamut or a heat-curable ink-jet ink for color filters which, after heat curing, has excellent adhesion, surface hardness, and flatness. The heat-curable ink-jet ink for color filters comprises a polyfunctional monomer, a binder resin, a pigment, a pigment dispersant, and a solvent, and is characterized in that the polyfunctional monomer is a compound having four or more ethylenically unsaturated bonds per molecule and that the binder resin is an acrylic copolymer obtained by copolymerizing monomers comprising (A) an epoxidized monomer having an epoxy group and an ethylenically unsaturated bond and (B) an alicyclic-hydrocarbon-containing monomer having an alicyclic hydrocarbon group and an ethylenically unsaturated bond.

Description

Thermosetting inkjet ink for color filter

The present invention relates to a thermosetting inkjet ink for a color filter used for forming pixels having a predetermined pattern using an inkjet method.

In recent years, with the development of personal computers, especially portable personal computers, the demand for liquid crystal displays, especially color liquid crystal displays, has been increasing.
In such a color filter of a liquid crystal display, usually, there are three primary color patterns of red (R), green (G), and blue (B), and electrodes corresponding to the R, G, and B pixels, respectively. By turning on and off the liquid crystal, the liquid crystal operates as a shutter, and light passes through each of the R, G, and B pixels, and color display is performed.
As a conventional method for producing a color filter, for example, a staining method can be mentioned. In this dyeing method, first, a water-soluble polymer material, which is a dyeing material, is formed on a glass substrate, patterned into a desired shape by a photolithography process, and then the obtained pattern is immersed in a dyeing bath. To get a colored pattern. By repeating this three times, R, G, and B pixels are formed. Another method is a pigment dispersion method. In this method, a photosensitive resin layer in which a pigment is dispersed is first formed on a substrate, and this is patterned to obtain a monochromatic pattern. Further, by repeating this process three times, R, G, and B pixels are formed. Still other methods include an electrodeposition method, a method in which a pigment is dispersed in a thermosetting resin, R, G, and B are printed three times, and then the resin is thermoset.

However, in any method, in order to color three colors of R, G, and B, it is necessary to repeat the same process three times, which causes a problem of high cost, and the yield decreases because the same process is repeated. There is a problem of doing.
As a method of manufacturing a color filter that solves these problems, Patent Document 1 describes that a pixel portion is formed by spraying a colored ink containing a thermosetting resin onto a substrate by an inkjet method and heating. Has been.

Japanese Patent Laid-Open No. 9-21910

Conventionally, when forming a pixel portion of a color filter using a thermosetting resin, it is common to use polymerization and / or crosslinking reaction of an acid component and an epoxy component. However, since the reactivity of the acid component and the epoxy component is very high, the viscosity gradually increases with time, and there is a problem in storage stability. If the viscosity gradually increases with time, stable ejection of ink by the ink jet method may be impaired, and the ink jet head may be clogged. Furthermore, when the polymerization and / or cross-linking reaction of the acid component and the epoxy component is used, there is a problem that the chemical resistance of the resulting colored layer is insufficient.
As color characteristics of color filters, color gamut reproducibility, high contrast, and high brightness have recently been required particularly in color television applications, but if the pixel portion has insufficient chemical resistance, As a result, cracks and color changes occur in the portion, and there is a risk that the brightness and color purity of the resulting color filter will be reduced.

Due to the recent demand for high brightness and high color purity for color filters, there is a demand for finer and higher density pigments contained in the inkjet ink. As the pigment is made finer and the pigment concentration is increased, the amount of the pigment dispersant needs to be increased together with the amount of the pigment contained in the inkjet ink. However, increasing the amount of pigment and pigment dispersant contained in the ink-jet ink for the color filter results in a relative decrease in components that contribute to the film properties of the cured film such as a binder, resulting in a decrease in the curability of the ink. However, there exists a problem that the adhesiveness and surface hardness of a cured film fall. In addition, when the pigment concentration is increased, drying of the ink is promoted, and there is a problem that unevenness of drying of the ink ejected into the black matrix by ink jetting is caused and the flatness of the pixel is deteriorated. When the flatness of a pixel is deteriorated, there is a problem that luminance and color purity are lowered.

In view of the above circumstances, the present invention intends to achieve the following first and second objects.
The first object of the present invention is to provide a thermosetting inkjet ink for a color filter, which can realize a color filter having excellent storage stability and curability, excellent chemical resistance after thermosetting, and good color gamut reproducibility. It is to be.
The second object of the present invention is to provide a thermosetting inkjet ink for a color filter which is excellent in adhesion, surface hardness and flatness after thermosetting even when the pigment concentration is increased. is there.

As a result of intensive studies, the present inventors have, as a thermosetting binder component of an ink-jet ink for a color filter, a polyfunctional monomer having an ethylenically unsaturated bond, an epoxy group-containing monomer, and an alicyclic hydrocarbon-containing monomer. The present inventors have found that the above object can be solved by using in combination with an acrylic copolymer obtained by copolymerizing a monomer group containing at least a monomer group, and have completed the present invention. In the present invention, a polyfunctional monomer having an ethylenically unsaturated bond is used as a thermosetting binder component, and when the inkjet ink is cured, the polyfunctional monomer is polymerized and / or crosslinked by heat.

More specifically, the following first thermosetting inkjet ink for a color filter is provided in order to achieve the first object.
That is, the first thermosetting inkjet ink for a color filter according to the present invention is a thermosetting inkjet ink for a color filter containing a polyfunctional monomer, a binder resin, a pigment, a pigment dispersant, and a solvent. The polyfunctional monomer is a compound having 4 or more ethylenically unsaturated bonds in one molecule, and the binder resin is (A) an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond; (B) It is an acrylic copolymer obtained by copolymerizing a monomer group containing at least an alicyclic hydrocarbon-containing monomer having an alicyclic hydrocarbon group and an ethylenically unsaturated bond.

In the first inkjet ink, in the acrylic copolymer, the (A) epoxy group-containing monomer is 20% by weight to 80% by weight in the total copolymerization component, and (B) the alicyclic hydrocarbon It is preferable that the contained monomer is 20% by weight to 80% by weight in the total copolymerization components from the viewpoint of storage stability and viscosity reduction of the ink, chemical resistance of the cured film, and color gamut reproducibility.

In the first thermosetting inkjet ink for a color filter, the (B) alicyclic hydrocarbon-containing monomer has a bridged alicyclic hydrocarbon group, so that the cured film has chemical resistance and color gamut reproduction. From the viewpoint of sex. The bridged alicyclic hydrocarbon group means a polycyclic aliphatic hydrocarbon group having a crosslinked structure in the alicyclic hydrocarbon group and having a polycyclic structure in the molecule.

In order to achieve the second object, the following second thermosetting inkjet ink for color filter is provided.
That is, the second thermosetting inkjet ink for a color filter according to the present invention is a thermosetting inkjet ink for a color filter containing a polyfunctional monomer, a binder resin, a pigment, a pigment dispersant, and a solvent. The polyfunctional monomer is a compound having 4 or more ethylenically unsaturated bonds in one molecule, and the binder resin is (A) an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond; (B) an acrylic copolymer obtained by copolymerizing a monomer group containing at least an alicyclic hydrocarbon-containing monomer having an alicyclic hydrocarbon group and an ethylenically unsaturated bond, and the acrylic copolymer And an epoxy resin different from the above.

In the second inkjet ink, the acrylic copolymer is a copolymer obtained by copolymerizing a monomer group containing at least the (A) epoxy group-containing monomer and (B) the alicyclic hydrocarbon-containing monomer. It is preferable that it is an acryl-type copolymer formed by making the carboxyl group-containing monomer (C) which has a carboxyl group and an ethylenically unsaturated bond react with one or more of the epoxy groups which have. In such a case, since the side chain of the acrylic copolymer has an ethylenically unsaturated bond and can be cross-linked with the polyfunctional monomer, adhesion after thermosetting, surface hardness, and flatness It is preferable from the point that it is excellent in the properties and further becomes excellent in the ITO resistance.

In the second inkjet ink, in the acrylic copolymer, the (A) epoxy group-containing monomer is 20% by weight to 80% by weight in the total copolymerization component, and (B) the alicyclic hydrocarbon From the viewpoint of compatibility with each component in the ink, adhesion after thermal curing of the ink, and surface hardness, the contained monomer is preferably 20% by weight to 80% by weight in the total copolymerization components.

In the second inkjet ink, the (B) alicyclic hydrocarbon-containing monomer preferably has a bridged alicyclic hydrocarbon group from the viewpoint of surface hardness after heat curing of the ink and solvent resistance. .

In the second inkjet ink, the weight of the epoxy resin relative to the sum of the polyfunctional monomer and the acrylic copolymer in the content ratio of the polyfunctional monomer, the acrylic copolymer, and the epoxy resin. The ratio (epoxy resin / (polyfunctional monomer + acrylic copolymer)) is 0.25 to 4, and the weight ratio of the acrylic copolymer to the polyfunctional monomer (acrylic copolymer) / Polyfunctional monomer) is preferably from 0.125 to 8 from the viewpoint of excellent adhesion after heat curing of the ink, surface hardness, and flatness.

The first thermosetting ink jet ink for color filter of the present invention can realize a color filter having excellent storage stability and curability, excellent chemical resistance after thermosetting, and good color gamut reproducibility.
Moreover, the thermosetting inkjet ink for 2nd color filters of this invention is excellent in the adhesiveness after heat curing, surface hardness, and flatness.

<First inkjet ink>
A first thermosetting inkjet ink for a color filter according to the present invention is a thermosetting inkjet ink for a color filter containing a polyfunctional monomer, a binder resin, a pigment, a pigment dispersant, and a solvent. The functional monomer is a compound having 4 or more ethylenically unsaturated bonds in one molecule, and the binder resin is (A) an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond ( B) An acrylic copolymer obtained by copolymerizing a monomer group containing at least an alicyclic hydrocarbon-containing monomer having an alicyclic hydrocarbon group and an ethylenically unsaturated bond.
In the thermosetting ink-jet ink for color filter of the present invention, the polyfunctionality having 4 or more ethylenically unsaturated bonds in one molecule without using conventional epoxy resin and acid component as thermosetting binder components. By combining and using an acrylic copolymer obtained by copolymerizing a monomer and a monomer group containing at least an epoxy group-containing monomer and an alicyclic hydrocarbon-containing monomer, it has excellent storage stability and curability, A color filter having excellent chemical resistance after curing and good color gamut reproducibility can be realized.
Further, in the present invention, since a thermosetting resin is used, there is an advantage that a special incidental equipment such as light irradiation is not required and productivity is high.

As a thermosetting binder component, a polyfunctional monomer having 4 or more ethylenically unsaturated bonds in one molecule is copolymerized with a monomer group containing at least an epoxy group-containing monomer and an alicyclic hydrocarbon-containing monomer. The reason why the above-described effects are exhibited by using the acrylic copolymer in combination is estimated as follows.
When a conventional epoxy resin and an acid component are mainly used as a thermosetting binder component, the reactivity between the acid component and the epoxy resin is very high, so that the viscosity gradually increases with time, and there is a problem in storage stability. It was. Moreover, there existed a problem that chemical resistance was inadequate.
In contrast, in the present application, an acrylic copolymer having an epoxy group and an alicyclic hydrocarbon in the side chain without using polymerization and / or crosslinking reaction of a conventional epoxy resin and an acid component as a thermosetting binder component. And a polyfunctional monomer having 4 or more ethylenically unsaturated bonds in one molecule in combination, polymerization of ethylenically unsaturated bonds and / or crosslinking reaction by heat, and polymerization of epoxy groups by heat and / or A cross-linking reaction is used.
In the present application, since the reaction between the epoxy group and the acid component is not essentially used and the acid component is not allowed to coexist with the epoxy group, the epoxy group hardly reacts and the storage stability is excellent.
An acrylic copolymer having an epoxy group and an alicyclic hydrocarbon in the side chain is excellent in curability because the epoxy group reacts by heat to polymerize and / or crosslink, and has an alicyclic hydrocarbon. Since it has an alicyclic hydrocarbon, it is difficult to undergo yellowing due to thermal history, and therefore color gamut reproducibility is good.
On the other hand, a polyfunctional monomer having four or more ethylenically unsaturated bonds in one molecule can be thermally polymerized to obtain a high hardness coating film having a high crosslinking density.
In the present invention, a synergistic effect of a combination of an acrylic copolymer having an epoxy group and an alicyclic hydrocarbon in these side chains and a polyfunctional monomer having 4 or more ethylenically unsaturated bonds in one molecule, A color filter having excellent storage stability and excellent curability and excellent chemical resistance after thermosetting and good color gamut reproducibility can be realized.

The thermosetting inkjet ink for color filter of the present invention contains at least a polyfunctional monomer, a binder resin, a pigment, a pigment dispersant, and a solvent, and may contain other components as necessary. It is. Hereinafter, each component used for the thermosetting inkjet ink for color filters of this invention is demonstrated.

<Multifunctional monomer>
In the present invention, a compound having 4 or more ethylenically unsaturated bonds in one molecule is used as the polyfunctional monomer. Here, the ethylenically unsaturated bond refers to a double bond between carbon atoms capable of radical polymerization, and examples of the functional group having such an ethylenically unsaturated bond include a vinyl group (CH ₂ ═CH—). , (Meth) acryl groups (CH ₂ ═CH—CH ₂ — and CH ₂ ═C (CH ₃ ) —CH ₂ —), (meth) acryloyl groups (CH ₂ ═CH—CO— and CH ₂ ═C (CH ₃ ) —CO—), (meth) acryloyloxy groups (CH ₂ ═CH—COO— and CH ₂ ═C (CH ₃ ) —COO—), —COO—CH═CH—COO— and the like. In the polyfunctional monomer used in the present invention, as long as there are four or more functional groups having an ethylenically unsaturated bond, they may be used singly or in combination of two or more. Moreover, the polyfunctional monomer used in this invention may be used individually by 1 type or in combination of 2 or more types. Among them, the ethylenically unsaturated bond preferably has four or more (meth) acryloyloxy groups and / or (meth) acryloyl groups from the viewpoint of curability of the cured film by thermal polymerization and / or crosslinking. In the present invention, acrylic ester and methacrylic ester are collectively referred to as “(meth) acrylate”. Others are the same.

In the present invention, the molecular weight of the polyfunctional monomer is preferably 2000 or less, more preferably 1000 or less, from the viewpoint of ink viscosity.

Examples of the compound having 4 or more ethylenically unsaturated bonds in one molecule include tetramethylol methane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, and ditrimethylolpropane tetra. (Meth) acrylate, alkyl-modified dipentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, alkyl-modified dipentaerythritol Penta (meth) acrylate, urethane hexa (meth) acrylate, polyester hexa (meth) acrylate, succinic acid modified dipentaerythritol Penta (meth) acrylate.
In addition, for example, pentaerythritol tetracaprolactonate tetra (meth) acrylate, diglycerin tetra (meth) acrylate, ditrimethylolpropane tetracaprolactonate tetra (meth) acrylate, ditrimethylolethane tetra (meth) acrylate, Ditrimethylolbutanetetra (meth) acrylate, ditrimethylolhexanetetra (meth) acrylate, ditrimethyloloctanetetra (meth) acrylate, tripentaerythritol hexa (meth) acrylate, tripentaerythritol hepta (meth) acrylate, tripentaerythritol octa ( (Meth) acrylates, tripentaerythritol polyalkylene oxide hepta (meth) acrylates and their ethylene oxides Id adduct, propylene oxide adduct, and the like. Further, for example, ethoxylated pentaerythritol tetra (meth) acrylate, neopentyl glycol oligoacrylate, 1,4-butanediol oligoacrylate, 1,6-hexanediol oligoacrylate, trimethylolpropane oligoacrylate, pentaerythritol oligoacrylate, urethane Examples include acrylate and epoxy acrylate.
Further, hexakis (methacryloyloxyethyl) cyclotriphosphazene (for example, “PPZ” manufactured by Kyoeisha Chemical Co., Ltd.), dipentaerythritol pentaacrylate hexamethylene diisocyanate / urethane prepolymer (for example, “UA-510H” manufactured by Kyoeisha Chemical Co., Ltd.) And so on.

The content of the polyfunctional monomer having 4 or more ethylenically unsaturated bonds in one molecule is preferably in the range of 5 to 80% by weight, more preferably 10% by weight, based on the solid content of the ink. It is preferably in the range of% to 60% by weight. If the amount is less than the above range, the cured film may have insufficient curability and chemical resistance. Further, if the amount is larger than the above range, a desired color may not be reproduced.
The content of the polyfunctional monomer having 4 or more ethylenically unsaturated bonds in one molecule is preferably 10 to 90% by weight in the solid content other than the pigment and the pigment dispersant described later. Further, it is preferably contained in an amount of 20 to 80% by weight from the viewpoints of ink viscosity reduction, storage stability, cured film curability, and chemical resistance. In addition, in this invention, solid content includes all the components except a solvent, and a liquid compound etc. are also contained in solid content.

In the present invention, as the polyfunctional monomer, a compound having 4 or more ethylenically unsaturated bonds in one molecule is used. For the purpose of ensuring low viscosity and ensuring proper ink jet discharge, as long as the effects of the present invention are not impaired, A compound having 2 to 3 ethylenically unsaturated bonds in the molecule may be used in combination. Even in this case, the compound having 4 or more ethylenically unsaturated bonds in one molecule is preferably contained in 50% by weight or more, more preferably 70% by weight or more in the total amount of the polyfunctional monomer. . In this invention, it is preferable that the compound which has 4 or more of ethylenically unsaturated bonds in 1 molecule is 100 weight% in the polyfunctional monomer whole quantity.

The compound having 2 to 3 ethylenically unsaturated bonds in the molecule that may be used in combination is preferably a compound having 2 to 3 (meth) acryloyl groups. For example, trimethylolpropane tri (meth) Acrylate, trimethylolethane tri (meth) acrylate, glycerol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, alkyl-modified dipentaerythritol tri (meth) acrylate, tri (meth) acrylate phosphate, tris (acryloxyethyl) ) Isocyanurate, tris (methacryloxyethyl) isocyanurate, and the like, but are not limited thereto, and various (meth) acrylates can be selected as appropriate.

<Binder resin>
The binder resin used in the present invention includes (A) an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond, and (B) an alicyclic carbonization having an alicyclic hydrocarbon group and an ethylenically unsaturated bond. An acrylic copolymer obtained by copolymerizing a monomer group containing at least a hydrogen-containing monomer.
The acrylic copolymer used in the present invention includes (A) an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond, and (B) a fat having an alicyclic hydrocarbon group and an ethylenically unsaturated bond. If a monomer group containing at least a cyclic hydrocarbon-containing monomer is copolymerized, each monomer is copolymerized at random, even if the monomers are randomly copolymerized. Also good.

By including an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond as a copolymerization component, the acrylic copolymer contains an epoxy group. Thereby, the reactivity by heat improves and brings about the effect | action that the sclerosis | hardenability of a cured film improves. (A) Examples of the epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond include glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate, 3,4-epoxycyclohexyl (meth) acrylate, 3,4 -Epoxycyclohexylmethyl (meth) acrylate and the like. Among them, glycidyl (meth) acrylate can be preferably used in the present invention.
(A) As an epoxy group containing monomer, it may be used individually by 1 type, and may be used in mixture of 2 or more types.

In the acrylic copolymer, the content of the (A) epoxy group-containing monomer is not limited as long as the binder resin can be cured to have a desired cured film. %, Preferably 30 to 70% by weight, more preferably 40 to 60% by weight. It is because it can be made excellent in sclerosis | hardenability of a cured film and compatibility with another component because the said content is in the said range.

By including an alicyclic hydrocarbon-containing monomer having (B) an alicyclic hydrocarbon group and an ethylenically unsaturated bond as a copolymerization component, the acrylic copolymer contains an alicyclic hydrocarbon group. become. Thereby, the sclerosis | hardenability of a cured film goes up and the effect | action that it is hard to receive yellowing by a heat history is brought about. Examples of the alicyclic hydrocarbon-containing monomer having an alicyclic hydrocarbon group and an ethylenically unsaturated bond include cyclohexyl (meth) acrylate, cyclohexylmethyl (meth) acrylate, 3-cyclohexenylmethyl (meth) acrylate, 4-isopropylcyclohexyl (meth) acrylate, 1-methylcyclohexyl (meth) acrylate, 2-methylcyclohexyl (meth) acrylate, 3-methylcyclohexyl (meth) acrylate, 4-methylcyclohexyl (meth) acrylate, 1-ethylcyclohexyl ( (Meth) acrylate, 4-ethylcyclohexyl (meth) acrylate, 2-tert-butylcyclohexyl (meth) acrylate, 4-tert-butylcyclohexyl (meth) acrylate, methyl ( ) Acrylate, 3,3,5-trimethylcyclohexyl (meth) acrylate, cycloheptyl (meth) acrylate, cyclooctyl (meth) acrylate, cyclononyl (meth) acrylate cyclodecyl (meth) acrylate, isobornyl (meth) acrylate, di Cyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxy (meth) acrylate, adamantyl (meth) acrylate, 2-alkyl-2-adamantyl (meth) acrylate, 3-hydroxy-1-adamantyl Examples include (meth) acrylate and 1-perfluoroadamantyl (meth) acrylate. Specific examples of 2-alkyl-2-adamantyl (meth) acrylate include 2-methyl-2-adamantyl (meth) acrylate and 2-ethyl-2-adamantyl (meth) acrylate.

As the alicyclic hydrocarbon-containing monomer, in particular, a fat having a bridged alicyclic hydrocarbon group and an ethylenically unsaturated bond from the viewpoint of suppressing yellowing due to thermal history and not reducing color gamut reproducibility. A cyclic hydrocarbon-containing monomer is preferred. Examples of the alicyclic hydrocarbon-containing monomer having a bridged alicyclic hydrocarbon group and an ethylenically unsaturated bond include isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, From dicyclopentenyloxy (meth) acrylate, adamantyl (meth) acrylate, 2-alkyl-2-adamantyl (meth) acrylate, 3-hydroxy-1-adamantyl (meth) acrylate, and 1-perfluoroadamantyl (meth) acrylate It is preferable that it is 1 or more types selected from the group which consists of a point which suppresses yellowing by a heat history and does not reduce color gamut reproducibility. Of these, dicyclopentanyl (meth) acrylate, adamantyl (meth) acrylate, and 2-alkyl-2-adamantyl (meth) acrylate can be preferably used in the present invention.
(B) As an alicyclic hydrocarbon containing monomer, it may be used individually by 1 type, and may be used in mixture of 2 or more types.

In the acrylic copolymer, the content of the (B) alicyclic hydrocarbon-containing monomer is not limited as long as the binder resin can have a desired cured film curing ability. It is preferably -80% by weight, more preferably 30-70% by weight, and further preferably 40-60% by weight. It is because it can be made excellent in sclerosis | hardenability of a cured film and compatibility with another component because the said content is in the said range.

As long as the acrylic copolymer does not impair the effects of the present invention and can ensure the performance required for each detail of the color filter, such as hardness and transparency, the (A) epoxy group-containing monomer and the above ( B) It may be a copolymer obtained by further using a copolymerizable monomer other than the alicyclic hydrocarbon-containing monomer. Specific examples of such monomers include, for example, methyl (meth) acrylate, n-butyl (meth) acrylate, allyl (meth) acrylate, hydroxyethyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate, 2 -Ethylhexyl (meth) acrylate, 2-hydroxylethyl (meth) acrylate, etc .; N-substituted maleimides such as N-methylmaleimide, N-cyclohexylmaleimide and the like can be exemplified.
The content of the copolymerizable monomer other than the (A) epoxy group-containing monomer and the (B) alicyclic hydrocarbon-containing monomer is 0% by weight to 50% by weight in the total copolymerization component. It is preferably 0% by weight to 30% by weight, and more preferably 0% by weight to 20% by weight.

In the acrylic copolymer of the present invention, it is preferable that an aromatic ring is not included from the viewpoint of suppressing yellowing. In addition, in the acrylic copolymer of the present invention, it is preferable from the viewpoint of improving storage stability that an acid component such as a structural unit derived from (meth) acrylic acid is not substantially contained. In the acrylic copolymer of the present invention, the phrase “substantially free of an acid component” means an acrylic copolymer that does not intentionally use a monomer containing an acid component such as a carboxyl group as the copolymer component.

The weight average molecular weight of the acrylic copolymer is not particularly limited, but is preferably 1,000 to 30,000, and more preferably 3000 to 20,000. If the weight average molecular weight of the acrylic copolymer is less than 1,000, physical properties such as strength and solvent resistance required for the cured layer as the details of the color filter may be insufficient. On the other hand, if the weight average molecular weight of the acrylic copolymer is more than 30,000, there is a fear that the viscosity is likely to increase, and the stability of the discharge amount and the discharge direction when discharging from the discharge head by the ink jet method are likely to occur. This is because there is a possibility that straightness may deteriorate and stability of long-term storage may deteriorate. Here, the weight average molecular weight can be determined as a standard polystyrene equivalent value by gel permeation chromatography (GPC).

As a method for synthesizing the acrylic copolymer used in the present invention, any copolymerization method may be used as long as it is a copolymerization method so that each monomer is contained in a desired ratio, and a general polymerization method can be used. Specifically, a method of polymerizing after dissolving or dispersing each of the monomers and the polymerization initiator in a solvent can be mentioned.

The content of the acrylic copolymer is preferably in the range of 5% by weight to 80% by weight, more preferably in the range of 10% by weight to 60% by weight, based on the solid content of the ink. . This is because if it is less than the above range, the cured film has poor curability and is likely to crack. Also, if the amount is larger than the above range, the viscosity may be easily increased, the stability of the discharge amount when discharging from the discharge head by the ink jet method, the straightness of the discharge direction may be deteriorated, and the long-term storage stability. Because there is a risk of getting worse. In addition, the content of the acrylic copolymer is preferably 10 to 90% by weight, and more preferably 20 to 80% by weight in solids other than the pigment and pigment dispersant described later. Is preferable from the viewpoints of heat resistance, cured film curability, chemical resistance, and color gamut reproducibility.

In addition, the content ratio of the polyfunctional monomer used in the present invention to the binder resin may be any ratio that can achieve desired ink suitability and cure suitability of the cured film. The weight ratio of polyfunctional monomer and binder resin (polyfunctional monomer / binder resin) contained in the curable inkjet ink is preferably in the range of 10/90 to 90/10, and in particular, 20/80 to It is preferably within the range of 80/20 from the viewpoints of ink viscosity reduction, storage stability, ejection stability in inkjet, cured film curability, chemical resistance, and color gamut reproducibility.

<Pigment>
As the pigment used in the present invention, a known pigment can be used. Specific examples of organic pigments that can be used in the present invention are shown in Tables 1 and 2 below.

Examples of inorganic pigments that can be used include titanium oxide, zinc white, lead sulfate, yellow lead, zinc yellow, bengara, cadmium red, ultramarine, bitumen, chromium oxide green, cobalt green, amber, titanium black, and synthetic iron black. And carbon black.
In addition, these pigments may be used independently and may mix and use 2 or more types.

In addition, the dispersion average particle diameter of the pigment used in the present invention is particularly selected so long as a desired color can be formed when the color filter colored layer is formed using the thermosetting inkjet ink for color filter. It is not limited, but usually it is preferably in the range of 0.01 μm to 0.30 μm, and particularly preferably in the range of 0.01 μm to 0.10 μm. This is because when the colored layer of the color filter is formed using the thermosetting inkjet ink for a color filter of the present invention, a colored layer having excellent luminance and contrast can be obtained. The dispersion average particle diameter of the pigment can be measured by a light scattering type particle size distribution measuring apparatus.

In the ink-jet ink according to the present invention, the content of the pigment is not particularly limited as long as a desired color can be developed when the colored layer of the color filter is formed, and depending on the type of pigment used. It is different and is not particularly limited. The pigment content is preferably in the range of 5 wt% to 70 wt% in the solid content of the ink, and more preferably in the range of 10 wt% to 60 wt%. This is because, if the content of the pigment is larger or smaller than the above range, the viscosity of the ink-jet ink may lack stability or the dispersed particle size may not be in an appropriate range.

In the inkjet ink according to the present invention, the blending weight ratio (P / V) of the pigment (P) and the solid content (V) other than the pigment is 0.25 to 1.2, particularly 0.5 to 1.2. It is preferable from the viewpoint of the balance between ink ejection performance, prevention of ink breakage, and film properties obtained. If the P / V ratio is too low, in order to obtain sufficient coloring power, it is necessary to increase the amount of ink droplets that adhere to the pixel formation region, which causes problems such as ink breaking from the pixel formation region. There is a case. On the other hand, if the P / V ratio is too high, there may be a problem that the ejection performance such as clogging or flight bending occurs in the ejection head or the film surface becomes rough.

<Pigment dispersant>
A pigment dispersant is blended in the thermosetting inkjet ink for color filter of the present invention in order to disperse the pigment satisfactorily. Examples of the pigment dispersant that can be used include cationic, anionic, nonionic, amphoteric, and silicone surfactants. Among the surfactants, polymer surfactants (polymer dispersants) as exemplified below are preferable. Further, a dispersion auxiliary resin such as a special acrylic polymer may be further used.
That is, polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; polyoxyethylene alkyl phenyl ethers such as polyoxyethylene octyl phenyl ether and polyoxyethylene nonyl phenyl ether Polymeric surfactants such as polyethylene glycol diesters such as polyethylene glycol dilaurate and polyethylene glycol distearate; sorbitan fatty acid esters; fatty acid-modified polyesters; tertiary amine-modified polyurethanes are preferably used.
The content of the pigment dispersant is preferably 5 to 50% by weight based on the total solid content of the ink, and more preferably 10 to 30% by weight based on the total solid content.

<Solvent>
The thermosetting inkjet ink for a color filter of the present invention is mixed with a solvent in order to prepare the ink so that the ink can be discharged from a high concentration liquid or immediately from the head.
In order to prepare the thermosetting inkjet ink for a color filter of the present invention into a high-concentration ink for storage or an ink that can be applied immediately, the solvent is particularly limited as long as it is a solvent that suitably dissolves and disperses solid components. Not.

Examples of the solvent include glycol ethers such as ethylene glycol monoethyl ether and diethylene glycol diethyl ether; glycol ether esters such as ethylene glycol monomethyl ether acetate; glycol oligomer ethers such as diethylene glycol monomethyl ether; diethylene glycol monomethyl ether acetate Glycol oligomer ether esters such as diethylene glycol monobutyl ether acetate; aliphatic or aromatic esters such as ethyl acetate, propyl benzoate; dicarboxylic acid diesters such as diethyl carbonate; and methyl 3-methoxypropionate Alkoxycarboxylates; ketocarboxylates such as ethyl acetoacetate; Alcohols or phenols such as ethanol, isopropanol and phenol; aliphatic or aromatic ethers such as diethyl ether and anisole; alkoxy alcohols such as 2-ethoxyethanol and 1-methoxy-2-propanol; diethylene glycol; Examples include glycol oligomers such as tripropylene glycol; alkoxy alcohol esters such as 2-ethoxyethyl acetate; ketones such as acetone and methyl isobutyl ketone.

Moreover, since the thermosetting inkjet ink for color filters according to the present invention contains a pigment, it is preferable to use a solvent that does not contain a hydroxyl group from the viewpoint of the dispersibility and dispersion stability of the pigment.
Preferred solvents include ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethyl adipate, dibutyl oxalate, dimethyl malonate, diethyl malonate, succinic acid Examples thereof include dimethyl and diethyl succinate. These solvents are mixed with or without mixing with highly dispersible solvents conventionally used for preparing pigment dispersions such as 3-methoxybutyl acetate and propylene glycol monomethyl ether acetate (PGMEA). It can be used as a solvent to prepare a pigment dispersion.

Further, when water is mixed in the solvent, the hydroxyl group of the water molecule is present in the solvent, so that the same problem as in the case of using the solvent having a hydroxyl group may be caused. Therefore, in order to substantially exclude moisture from the acid-epoxy crosslinking reaction system, it is preferable to prepare an inkjet ink using an organic solvent having low miscibility with water. From this viewpoint, the solubility of the solvent for preparing the ink-jet ink in water is preferably 20 parts by weight or less with respect to 100 parts by weight of water having a liquid temperature of 20 ° C.
Among the solvents mentioned as specific examples, diethylene glycol monobutyl ether acetate does not have a hydroxyl group, and its solubility in 100 parts by weight of water at a liquid temperature of 20 ° C. is low at 6.5 parts by weight. Is particularly preferable.

The solvent is usually used at a ratio of 40 to 95% by weight with respect to the total amount of the ink-jet ink containing the solvent to prepare the ink-jet ink. When the amount of the solvent is too small, the viscosity of the inkjet ink is high, and in the case of the inkjet ink, it becomes difficult to discharge from the inkjet head. Also, if there is too much solvent, the ink will break from the predetermined ink layer formation site, the amount of ink that can be deposited on the ink layer formation site will be insufficient, the film thickness after drying will be too thin, Accordingly, a sufficient transmission density cannot be obtained.

<Thermal polymerization initiator>
In this invention, in order to harden | cure by superposing | polymerizing thru | or crosslinking reaction of the said ethylenically unsaturated bond with a heat | fever, you may contain the thermal-polymerization initiator. Examples of thermal polymerization initiators that thermally cure ethylenically unsaturated bonds include various peroxides such as benzoyl peroxide, azo compounds such as azobisbutyronitrile, onium salts, and triazine compounds having a trihalomethyl group. , Azide compounds, quinonediazides, oxime ester compounds, triarylmonoalkylborate compounds, and the like can be used.

The above thermal polymerization initiators can be used singly or in combination of two or more. The amount of the thermal polymerization initiator used in the present invention is usually in the range of 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight per 100 parts by weight of the polyfunctional monomer. If the blending amount of the thermal polymerization initiator is less than 0.1 part by weight, curing may be insufficient and a tough coating film may not be formed. Moreover, when the compounding quantity of a thermal-polymerization initiator exceeds 10 weight part, there exists a possibility that the storage stability of an ink may be inferior.

<Hardener / Accelerator>
In the present invention, an epoxy curing agent / accelerator may be contained for the purpose of efficiently reacting the epoxy group in the acrylic copolymer. As epoxy curing agents / accelerators, unmodified aliphatic polyamines, modified aliphatic polyamines, unmodified aromatic polyamines, modified aromatic polyamines, modified alicyclic polyamines, unmodified alicyclic polyamines, unmodified polyaminoamides, modified Polyaminoamide, tertiary amine, acid anhydride, hydrazide derivative, dicyandiamide and its derivative, boron halide complex, organometallic complex, onium salt, polythiol, phenol formaldehyde condensate, phenol and its derivative, other compound having hydroxyl group, isocyanate, Blocked isocyanate, ketimine, imidazole and derivatives thereof can be used.

The above curing agents / accelerators can be used singly or in combination of two or more. The amount of the curing agent / accelerator used in the present invention is usually in the range of 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, per 100 parts by weight of the acrylic copolymer. is there. If the blending amount of the curing agent / accelerator is less than 0.1 part by weight, curing may be insufficient and a tough coating film may not be formed. Moreover, when the compounding quantity of a hardening | curing agent and an accelerator exceeds 10 weight part, there exists a possibility that the storage stability of an ink may be inferior.

<Other ingredients>
Furthermore, the thermosetting inkjet ink for color filters of this invention can mix | blend 1 type (s) or 2 or more types of other additives as needed. The following can be illustrated as such an additive.
a) Filler: For example, glass, alumina and the like.
b) Adhesion promoter: for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane.
c) Leveling agents: For example, vinyl polymers such as polyoxyalkylene surfactants, fatty acid ester surfactants, special acrylic polymers, vinyl ether polymers, and the like.
d) Anti-aggregation agent: for example, sodium polyacrylate.

<Ink production method>
The thermosetting inkjet ink for a color filter of the present invention may be produced by adding and mixing each component into a solvent and dissolving or dispersing the solid component.
However, if the pigment is directly put into the whole solvent together with other components such as a resin and mixed with stirring, the pigment is often not sufficiently dispersed in the solvent. Therefore, usually, a solvent having good dispersibility and dispersion stability of the pigment is prepared, and the pigment is added thereto together with the dispersant, and sufficiently stirred with a dissolver or the like to prepare a pigment dispersion. Then, the obtained pigment dispersion is put into a solvent together with components other than the pigment, and sufficiently stirred and mixed with a dissolver or the like, whereby the ink-jet ink according to the present invention can be obtained.

As the remaining solvent into which the pigment dispersion is charged, an inkjet ink having a composition obtained by subtracting the amount of the solvent used for preparing the pigment dispersion from the final composition of the entire solvent is diluted to the final concentration. May be completed. Alternatively, a high-concentration inkjet ink may be prepared by introducing the pigment dispersion into a relatively small amount of solvent. The high-concentration ink-jet ink can be stored as it is and diluted to the final concentration just before use and used in the ink-jet method.

The thermosetting inkjet ink for color filter of the present invention can be used for forming a colored layer of a color filter by an inkjet method. Among them, the color gamut reproducibility is good and the luminance is high. Is preferably used for forming a colored layer.

The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

<Second inkjet ink>
The second thermosetting inkjet ink for color filters according to the present invention is a thermosetting inkjet ink for color filters containing a polyfunctional monomer, a binder resin, a pigment, a pigment dispersant, and a solvent, The functional monomer is a compound having 4 or more ethylenically unsaturated bonds in one molecule, and the binder resin is (A) an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond ( B) An acrylic copolymer obtained by copolymerization containing at least an alicyclic hydrocarbon-containing monomer having an alicyclic hydrocarbon group and an ethylenically unsaturated bond is different from the acrylic copolymer. It contains an epoxy resin.
In the thermosetting inkjet ink for color filter of the present invention, as a thermosetting binder component, a polyfunctional monomer having four or more ethylenically unsaturated bonds in one molecule, an epoxy group-containing monomer, and an alicyclic carbonization Even when the pigment concentration is increased by using a combination of an acrylic copolymer obtained by copolymerization containing at least a hydrogen-containing monomer and an epoxy resin different from the acrylic copolymer, A color filter having a colored layer excellent in adhesion, surface hardness, and flatness after thermosetting can be realized.
Further, in the present invention, since a thermosetting resin is used, there is an advantage that a special incidental equipment such as light irradiation is not required and productivity is high.

As a thermosetting binder component, an acrylic prepared by copolymerizing at least a polyfunctional monomer having four or more ethylenically unsaturated bonds in one molecule, an epoxy group-containing monomer, and an alicyclic hydrocarbon-containing monomer. The reason why the above-described effect is exhibited by using a combination of an epoxy resin different from the acrylic copolymer and at least three types of epoxy resins is presumed as follows.
That is, the epoxy group of the acrylic copolymer and an epoxy resin different from the epoxy group are ring-opened and polymerized and / or crosslinked by a thermal polymerization initiator (or heat), thereby improving the adhesion of the cured film. Furthermore, the surface hardness and solvent resistance of the cured film become superior due to the alicyclic hydrocarbon introduced into the acrylic copolymer. By combining therewith a polyfunctional monomer having 4 or more ethylenically unsaturated bonds in one molecule, the crosslink density of the cured film is increased, and the surface hardness is further improved. Wet spreadability is improved and flatness is improved. And it is estimated that the colored layer excellent in the adhesiveness after heat curing, surface hardness, and flatness is realizable even if it is a case where the pigment density | concentration is made high by the synergistic effect of these three components.

Similar to the first inkjet ink, the second inkjet ink contains at least a polyfunctional monomer, an acrylic copolymer and an epoxy resin as a binder resin, a pigment, a pigment dispersant, and a solvent. And may contain other components. Hereinafter, each component used for the second inkjet ink will be described. Description of matters similar to those of the first ink-jet ink will be omitted, and matters different from those of the first ink-jet ink will be described with emphasis. Matters described with respect to the first ink-jet ink are cited for the description of the second ink-jet ink unless the difference described below applies.

<Multifunctional monomer>
In the second inkjet ink, the same polyfunctional monomer used in the first inkjet ink is used.
Also in the second inkjet ink, it is preferable from the viewpoint of surface hardness and adhesion that the ethylenically unsaturated bond has 4 or more (meth) acryloyloxy groups and / or (meth) acryloyl groups.
The molecular weight of the polyfunctional monomer is preferably in the same range as in the first inkjet ink in the second inkjet ink. That is, the molecular weight of the polyfunctional monomer is preferably 2000 or less, more preferably 1000 or less, from the viewpoint of the ink viscosity and the flatness of the cured film.

In the second ink-jet ink, the content of the polyfunctional monomer having 4 or more ethylenically unsaturated bonds in one molecule is in the range of 0.5 wt% to 30 wt% with respect to the solid content of the ink. It is preferable that it is in the range of 5.0% by weight to 20% by weight. This is because if it is less than the above range, there is a risk of deterioration of flatness due to a decrease in wettability and surface hardness. Further, if the amount is larger than the above range, the solvent resistance of the ink cured film may be deteriorated due to the balance with the acrylic copolymer content.

<Binder resin>
The binder resin used in the second ink-jet ink is an acrylic copolymer obtained by copolymerizing a monomer group containing at least an (A) epoxy group-containing monomer and (B) an alicyclic hydrocarbon-containing monomer, It contains an epoxy resin different from the acrylic copolymer.
[Acrylic copolymer]
In the second inkjet ink, the same acrylic copolymer used in the first inkjet ink is used.
Since the acrylic copolymer contains an epoxy group, the adhesiveness to the ink adhesion surface is improved and the compatibility with other components is improved.
In addition, since the acrylic copolymer contains an alicyclic hydrocarbon group, the curability of the cured film is improved, the surface hardness is improved, and the solvent resistance is improved.

Among the above alicyclic hydrocarbon-containing monomers, alicyclic hydrocarbon-containing monomers having a bridged alicyclic hydrocarbon group and an ethylenically unsaturated bond from the viewpoint of the surface hardness and solvent resistance of the cured film, among others. It is preferable that As the alicyclic hydrocarbon-containing monomer having a bridged alicyclic hydrocarbon group and an ethylenically unsaturated bond, preferred for the first ink-jet ink are the flatness of the cured film, the surface hardness and the resistance to resistance. It is also preferable from the viewpoint of solvent properties.
In particular, in the second inkjet ink, dicyclopentanyl (meth) acrylate, 1-adamantyl (meth) acrylate, and 2-adamantyl (meth) acrylate can be preferably used.

In the acrylic copolymer, the content of the (B) alicyclic hydrocarbon-containing monomer is not limited as long as the binder resin can have the desired surface hardness and solvent resistance of the cured film. As in the case of the inkjet ink, it is preferably 20 to 80% by weight, more preferably 30 to 70% by weight, and further preferably 40 to 60% by weight in the total copolymer components.

In the second inkjet ink, (A) an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond, and (B) an alicyclic hydrocarbon having an alicyclic hydrocarbon group and an ethylenically unsaturated bond. It is formed by reacting a carboxyl group-containing monomer (C) having a carboxyl group and an ethylenically unsaturated bond with one or more epoxy groups of a copolymer obtained by copolymerizing a monomer group containing at least a monomer containing An acrylic copolymer is preferred.
In such a case, the acrylic copolymer has an ethylenically unsaturated bond in the side chain, and the acrylic copolymer is polymerized and / or crosslinked by the ethylenically unsaturated bond with the polyfunctional monomer. Therefore, the adhesiveness after heat curing, the surface hardness, and the flatness are excellent, and further, the ITO forming resistance is excellent.
In addition, the ITO resistance is the formation of a cured layer such as a colored layer (hereinafter referred to as a cured layer) using the ink when forming a transparent electrode film (for example, ITO), so that wrinkles and cracks are less likely to occur. , A characteristic that hardly causes wrinkles and cracks in adjacent layers. When forming the colored layer of the color filter using inkjet ink, after forming the colored layer on the substrate, if necessary, a protective film is formed thereon, and then a transparent electrode film is formed. There is a problem that wrinkles are generated on the surface of the transparent electrode film when the electrode film is formed. As a method for forming the transparent electrode film, it is necessary to heat the substrate under a reduced pressure atmosphere such as a vacuum deposition method, a sputtering method, or an ion plating method. For example, when a typical ITO film is vacuum-deposited as a transparent electrode film, the underlying colored layer or protective film is exposed to a high temperature and an ultra-low pressure due to vacuum. When a hardened layer such as a colored layer formed from ink is exposed to such ultra-low pressure and high temperature conditions, the hardened layer thermally expands and contracts to generate wrinkles, which distorts adjacent layers such as transparent electrode films. It is thought that wrinkles and cracks occur on the surface. If wrinkles or cracks occur on the surface of the transparent electrode film, the local resistivity is increased at the location where the transparent electrode film is generated, resulting in disconnection, resulting in an afterimage, and in turn causing display defects. Therefore, if the ITO forming resistance is excellent, a high-intensity color filter with reduced display defects can be obtained.

Specific examples of the carboxyl group-containing monomer (C) having a carboxyl group and an ethylenically unsaturated bond include methacrylic acid, acrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, α- (hydroxymethyl). ) Acrylic acid, (meth) acryloyloxyethyl succinic acid monoester, (meth) acryloyloxyphthalic acid monoester, and the like. Among these, acrylic acid, methacrylic acid, and maleic acid can be preferably used in the present invention, and acrylic acid and methacrylic acid can be particularly preferably used.

A carboxyl group-containing monomer (C) is reacted with one or more of the epoxy groups of a copolymer obtained by copolymerizing (A) an epoxy group-containing monomer and (B) an alicyclic hydrocarbon-containing monomer. In the acrylic copolymer, a part of the epoxy group in the side chain of the copolymer is used for the reaction with the carboxyl group-containing monomer (C), and the side chain has a repeating ethylenically unsaturated bond. Comes with a unit.
In such an acrylic copolymer, the content of the repeating unit having an ethylenically unsaturated bond in the side chain is preferably 10 to 80 mol% in all repeating units of the copolymer, and further 20 It is preferably ˜60 mol%. This is because when the content is within the above range, the reactivity with the polyfunctional monomer is improved, and in particular, the ITO forming resistance can be improved.
In the acrylic copolymer having a repeating unit having an ethylenically unsaturated bond in the side chain, the content of the repeating unit containing an epoxy group in the side chain is 10 to 10 in all repeating units of the copolymer. It is preferably 70 mol%, more preferably 20 to 40 mol%, and the content of the repeating unit containing an alicyclic hydrocarbon in the side chain is the total repeating unit in the copolymer. It is preferably 10 to 70 mol%, more preferably 20 to 50 mol%, from the viewpoints of adhesion of the cured film, surface hardness, and ITO resistance.

In the second inkjet ink, the content of the acrylic copolymer is preferably in the range of 0.5 to 30% by weight, more preferably 1.0% by weight, based on the solid content of the ink. It is preferably in the range of from 15% to 15% by weight. This is because if the amount is less than the above range, the solvent resistance of the ink cured film may be deteriorated. Moreover, it is because there exists a possibility that surface hardness may deteriorate when more than the said range. The content of the acrylic copolymer is preferably 10 to 70% by weight, and more preferably 10 to 40% by weight in the solid content other than the pigment and pigment dispersant described later. It is preferable from the point of hardness.

[Epoxy resin]
The epoxy resin used together as the binder resin in the present invention is a resin different from the acrylic copolymer having the epoxy group in the side chain. The epoxy resin used in the present invention preferably has two or more epoxy groups in one molecule from the viewpoint of film physical properties such as solvent resistance and adhesion of pixels formed by inkjet ink. As an epoxy group, what is necessary is just a group which has an epoxide structure, for example, a glycidyl group, an oxyethylene group, an epoxycyclohexyl group etc. can be shown.

The epoxy resin preferably has a polystyrene-equivalent weight average molecular weight of 3,000 to 20,000, more preferably 4,000 to 15,000, from the viewpoint of increasing the crosslink density of the cured film and improving the ink jetting performance by lowering the viscosity. It is.
If the molecular weight of the epoxy resin is less than 3000, physical properties such as strength and solvent resistance required for the cured layer as the details of the color filter are likely to be insufficient, and if the molecular weight is more than 20000, the viscosity increases. This is because the stability of the discharge amount and the straightness in the discharge direction when discharging from the discharge head by the ink jet method may be deteriorated, and the stability of long-term storage may be deteriorated.

The epoxy resin is not particularly limited as long as it contains two or more epoxy groups in one molecule. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, brominated bisphenol A type epoxy resin, bisphenol S Type epoxy resin, diphenyl ether type epoxy resin, hydroquinone type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, fluorene type epoxy resin, phenol novolac type epoxy resin, orthocresol novolac type epoxy resin, trishydroxyphenylmethane type epoxy resin, Trifunctional epoxy resin, tetraphenylolethane type epoxy resin, dicyclopentadienephenol type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol A nucleated poly Lumpur type epoxy resins, polypropylene glycol type epoxy resins, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, glyoxal type epoxy resins, alicyclic epoxy resins, and the like heterocyclic epoxy resin.

More specifically, bisphenol A type epoxy resin such as trade name Epicoat 828 (made by Japan Epoxy Resin Co., Ltd.), trade name Epicoat 807 (made by Japan Epoxy Resin Co., Ltd.), trade name YDF-175S (produced by Toto Kasei Co., Ltd.), etc. Bisphenol F type epoxy resin, brominated bisphenol A type epoxy resin such as trade name YDB-715 (manufactured by Toto Kasei Co., Ltd.), bisphenol S type epoxy resin such as trade name EPICLON EXA1514 (made by Dainippon Ink and Chemicals, Inc.), trade name Biphenyl such as hydroquinone type epoxy resin such as YDC-1312 (manufactured by Toto Kasei Co., Ltd.), naphthalene type epoxy resin such as brand name EPICLON EXA4032 (manufactured by Dainippon Ink & Chemicals, Inc.), brand name Epicoat YX4000H (made by Japan Epoxy Resin Co., Ltd.) Epoxy resin, bisphenol A type novolak epoxy resin such as trade name Epicoat 157S70 (made by Japan Epoxy Resin), phenol such as trade name Epicoat 154 (made by Japan Epoxy Resin), trade name YDPN-638 (made by Toto Kasei) Novolak type epoxy resin, cresol novolac type epoxy resin such as trade name YDCN-701 (manufactured by Tohto Kasei Co., Ltd.), dicyclopentadiene phenol type epoxy resin such as trade name EPICLON HP-7200 (manufactured by Dainippon Ink and Chemicals), product Trishydroxyphenylmethane type epoxy resin such as name Epicoat 1032H60 (manufactured by Japan Epoxy Resin), trifunctional type epoxy resin such as trade name VG3101M80 (made by Mitsui Chemicals), brand name Epicoat 1031S (ja Tetraphenylolethane type epoxy resin such as Denepoxy Resin Co., Ltd., tetrafunctional epoxy resin such as Denacol EX-411 (manufactured by Nagase Kasei Kogyo Co., Ltd.), ST-3000 (made by Toto Kasei Co., Ltd.), etc. Hydrogenated bisphenol A type epoxy resin, glycidyl ester type epoxy resin such as trade name Epicoat 190P (Japan Epoxy Resin Co., Ltd.), glycidyl amine type epoxy resin such as trade name YH-434 (manufactured by Toto Kasei Co., Ltd.), trade name YDG- Glyoxal type epoxy resin such as 414 (manufactured by Toto Kasei Co., Ltd.), alicyclic epoxy resin such as brand name EHPE3150 (manufactured by Daicel Chemical Industries, Ltd.), and alicyclic type such as brand name Epollide GT-401 (manufactured by Daicel Chemical Industries, Ltd.) Such as polyfunctional epoxy compounds, triglycidyl isocyanate (TGIC) Heterocyclic epoxy resins can be exemplified. Further, if necessary, a trade name Neotote E (manufactured by Toto Kasei Co., Ltd.) can be mixed as an epoxy reactive diluent.

Among these epoxy resins, alicyclic epoxy resins such as trade name EHPE3150 (manufactured by Daicel Chemical Industries) and bisphenol A type novolac epoxy resins such as Epicoat 157S70 (manufactured by Japan Epoxy Resin) are preferable. An alicyclic epoxy resin such as trade name EHPE3150 (manufactured by Daicel Chemical Industries) is preferred.
These epoxy resins may be used alone or in combination of two or more.

The content of the epoxy resin is preferably 2.0% to 35% by weight, more preferably 5.0% to 30% by weight, based on the solid content of the ink. This is because if the epoxy resin content is too small, sufficient thermosetting may not be obtained. Moreover, when there is too much content of an epoxy resin, it will cause a curing defect.

Further, in the content ratio of the polyfunctional monomer, the acrylic copolymer, and the epoxy resin used in the present invention, it is possible to achieve desired adhesion, surface hardness, and flatness. Although not particularly limited, the weight ratio of the epoxy resin to the sum of the polyfunctional monomer and the acrylic copolymer (epoxy resin / (polyfunctional monomer + acrylic copolymer)) is 0.25. And the weight ratio of the acrylic copolymer to the polyfunctional monomer (acrylic copolymer / polyfunctional monomer) is 0.125 to 8, the adhesion, surface hardness From the viewpoints of flatness, solvent resistance and storage stability. Among them, the weight ratio of the epoxy resin to the sum of the polyfunctional monomer and the acrylic copolymer (epoxy resin / (the polyfunctional monomer + the acrylic copolymer)) is 0.3 to 1. The weight ratio of the acrylic copolymer to the polyfunctional monomer (the acrylic copolymer / the polyfunctional monomer) is preferably 0.15 to 3.

<Pigment>
In the second inkjet ink, the same pigment as that used in the first inkjet ink is used.
The content of the pigment is not particularly limited as long as it can produce a desired color when a colored layer of a color filter is formed, and is not particularly limited depending on the type of pigment used. In the second ink-jet ink, the content is set relatively high in order to achieve the second object of increasing the pigment concentration. Specifically, the content of the pigment is preferably in the range of 20% by weight to 70% by weight, and more preferably in the range of 30% by weight to 60% by weight, in the solid content of the ink.

<Pigment dispersant>
In the second inkjet ink, the same pigment dispersant used in the first inkjet ink is used.
<Solvent>
In the second inkjet ink, the same solvent as that used in the first inkjet ink is used.

<Thermal polymerization initiator>
In the second ink-jet ink, the same ethylenic unsaturated bond as that used in the first ink-jet ink can be used because the ethylenically unsaturated bond is cured by polymerization or crosslinking reaction.
Moreover, in order to harden | cure by carrying out the superposition | polymerization thru | or crosslinking reaction of the said epoxy resin in the said acrylic resin and the said acrylic copolymer by heat | fever, you may contain the thermal-polymerization initiator. Such a thermal polymerization initiator is not particularly limited, but is preferably an acid anhydride from the viewpoint of high storage stability and low calorific value.
Examples of the acid anhydride include polyvalent carboxylic acid anhydrides, and specifically include phthalic anhydride, itaconic anhydride, succinic anhydride, citraconic anhydride, dodecenyl succinic anhydride, tricarballylic anhydride, maleic anhydride. Aliphatic polycarboxylic dianhydrides such as acids, hexahydrophthalic anhydride, dimethyltetrahydrophthalic anhydride, hymic anhydride, nadic anhydride, and other aliphatic or alicyclic dicarboxylic dianhydrides; pyromellitic anhydride , Aromatic polycarboxylic acid anhydrides such as trimellitic anhydride and benzophenone tetracarboxylic anhydride; and ester group-containing acid anhydrides such as ethylene glycol bistrimellilate and glyceryl tristrimellate An epoxy resin curing agent made of carboxylic acid anhydride can also be suitably used. .

The blending amount of the thermal polymerization initiator used in the second inkjet ink is preferably in the range of 0.1 wt% to 5.0 wt% in the solid content of the ink, and more preferably 0.15 wt%. It is preferably in the range of -3.0% by weight. When there is too little content of a thermal-polymerization initiator, hardening may become inadequate and there exists a possibility that a tough coating film cannot be formed. Moreover, when there is too much content of a thermal-polymerization initiator, there exists a possibility that storage stability may be inferior.

<Ink production method>
The second ink-jet ink can be produced in the same manner as the method for producing the first ink-jet ink.
The application of the second ink-jet ink is also the same as that of the first ink-jet ink, and is particularly preferably used for forming a colored layer that is required to have good color gamut reproducibility and high luminance.

Hereinafter, the present invention will be described more specifically with reference to examples.
Example A series is an experiment on the first inkjet ink. On the other hand, Example B series is an experiment related to the second inkjet ink.
<Example A series>
Examples A1 to A9 and Comparative Examples A1 to A9 were performed according to the following procedure.
1. Preparation of pigment dispersion A pigment, a pigment dispersant, and a solvent are mixed in the following ratio, 200 parts by weight of zirconia beads having a diameter of 0.5 mm are added, and dispersed for 3 hours using a paint shaker (manufactured by Asada Tekko). A pigment dispersion was prepared.

(1) Preparation of red pigment dispersion [Composition of pigment dispersion]
・ C. I. Pigment Red 254: 4.5 parts by weight C.I. I. Pigment Red 177: 7.5 parts by weight C.I. I. Pigment Yellow 150: 3.0 parts by weight-Pigment dispersant (Disperbyk 161: trade name, manufactured by Big Chemie Japan, solid content in solvent: 30% by weight): 30 parts by weight-BDGAC (diethylene glycol monobutyl ether acetate): 55 parts by weight

(2) Preparation of green pigment dispersion [Composition of pigment dispersion]
・ C. I. Pigment Green 36: 10 parts by weight C.I. I. Pigment Yellow 150: 5 parts by weight Pigment dispersant (Disperbyk 161: trade name, manufactured by Big Chemie Japan, solid content in solvent: 30% by weight): 30 parts by weight BDGAC (diethylene glycol monobutyl ether acetate): 55 parts by weight

(3) Preparation of blue pigment dispersion [Composition of pigment dispersion]
・ C. I. Pigment Blue 15: 6: 9.5 parts by weight C.I. I. Pigment Violet 23: 0.5 part by weight-pigment dispersant (Disperbyk 161: trade name, manufactured by Big Chemie Japan, solid content in solvent: 30% by weight): 20 parts by weight-BDGAC (diethylene glycol monobutyl ether acetate): 70 parts by weight

2. Synthesis of Acrylic Copolymer 150 parts by weight of diethylene glycol monobutyl ether acetate (BDGAC) was charged into a reaction vessel equipped with a gas introduction tube, a thermometer, a condenser, and a stirrer, and replaced with nitrogen gas and heated to 100 ° C. Thereto was added dropwise a mixture of 50 parts by weight of glycidyl methacrylate (GMA), 50 parts by weight of dicyclopentanyl methacrylate (DCPMA) and 10 parts by weight of t-butylperoxy-2-ethylhexanoate over 2 hours.
A GMA / DCPMA copolymer (solution) was obtained by reacting at 100 ° C. for 3 hours after completion of the dropping.
Similarly, an acrylic copolymer was synthesized with 1-adamantyl methacrylate (ADAMA), 2-methyl-2-adamantyl methacrylate (MADAMA), and benzyl methacrylate (BzMA) in the proportions shown in Table 3 below.
The weight average molecular weight (Mw) of the obtained acrylic copolymers a-1 to a-5 was measured with a GPC measuring device (HLC-8220 GPC, manufactured by Tosoh Corporation) under the conditions of polystyrene standards.

3. Preparation of ink The acrylic copolymers (a-1 to a-5), polyfunctional monomers (b-1 to b-3) and solvent (BDGAC) obtained above were blended as shown in Table 4 below. Thus, inkjet inks of Examples A1 to A9 were prepared. Ink jet inks of Comparative Examples A1 to A9 were prepared by blending as shown in Table 5 below.
Next, as the red ink, the red pigment dispersion and the resin composition are sufficiently mixed, and the blending weight ratio (P / V) between the pigment (P) and the solid content (V) other than the pigment is 0.00. 6 and BDGAC was added so that the solid content in the mixed solution was 20% by weight to prepare a thermosetting inkjet ink for a color filter.
As the green ink, the green pigment dispersion and the resin composition are sufficiently mixed, and the blending weight ratio (P / V) between the pigment (P) and the solid content (V) other than the pigment is 0.7, and BDGAC was added so that the solid content in the mixed solution was 20% by weight to prepare a thermosetting inkjet ink for a color filter.
As the blue ink, the blue pigment dispersion and the resin composition are sufficiently mixed, and the blending weight ratio (P / V) of the pigment (P) and the solid content (V) other than the pigment is 0.25, and BDGAC was added so that the solid content in the mixed solution was 20% by weight to prepare a thermosetting inkjet ink for a color filter.
As polyfunctional monomers, b-1: a dipentaerythritol hexa and pentaacrylate mixture (product name: Aronix M403, pentaacrylate 50-60%, manufactured by Toa Gosei), b-2: ditrimethylolpropane tetraacrylate (product name) : Aronix M408, manufactured by Toagosei Co., Ltd.). b-3: Isocyanuric acid EO modified di- and triacrylate (product name: Aronix M315, manufactured by Toagosei Co., Ltd.) were used.

The obtained thermosetting inkjet ink for each color filter was evaluated. The chromaticity, NMP resistance, NaOH resistance, and surface hardness were evaluated by forming a cured resin film as follows. The evaluation results are shown in Table 6.
(Formation of coating film)
Each inkjet ink was applied onto a 0.7 mm thick glass substrate (Corning Corp., 1737) by spin coating.
Thereafter, prebaking was performed on a hot plate at 90 ° C. for 10 minutes. Then, in a clean oven, heating was performed at 200 ° C. for 30 minutes to perform post baking, and heating was further performed at 240 ° C. for 30 minutes to perform post baking, thereby forming a colored layer.

〔Evaluation methods〕
(1) Storage stability 50 g of each of the obtained ink-jet inks was collected in a glass bottle and allowed to stand at 60 ° C. for 1 week in a sealed state. The viscosity of the inkjet ink after being allowed to stand was measured.
[Evaluation criteria]
○: The difference in the measured value of the viscosity was less than 5% before and after being left standing.
(Triangle | delta): The difference of the measured value of a viscosity was 5% or more and less than 10% before and behind standing.
X: The difference of the measured value of a viscosity was 10% or more before and after leaving.

(2) Chromaticity Chromaticity (Y, x, y) with a C light source was measured using a microspectrophotometer (“OPS-SP200” manufactured by Olympus Optical Co., Ltd.).

(3) NMP resistance The substrate on which the colored layer was formed was immersed in an NMP solution for 30 minutes, and the color difference before and after immersion was measured.
[Evaluation criteria]
○: The color difference was 2 or less before and after the NMP immersion.
(Triangle | delta): The color difference was 2 excess 5 or less before and behind NMP immersion.
X: The color difference was more than 5 before and after NMP immersion.

(4) NaOH resistance The substrate on which the colored layer was formed was immersed in a 10% NaOHaq solution for 15 minutes, and the color difference before and after immersion was measured.
[Evaluation criteria]
A: The color difference was 2 or less before and after being immersed in a 10% NaOHaq solution.
Δ: The color difference was more than 2 and 5 or less before and after being immersed in a 10% NaOHaq solution.
X: The color difference was more than 5 before and after being immersed in a 10% NaOHaq solution.

(5) Surface hardness (pencil hardness)
The pencil hardness of the surface of the color filter layer was evaluated by a “pencil scratch test” in accordance with JIS K 5400-1990 8.4.1.

From the results of Table 6, the ink-jet ink according to the first invention has excellent storage stability, excellent curability, excellent chemical resistance after heat curing, high brightness, and good color gamut reproducibility. Was confirmed.

<Example B series>
Examples B1 to B14 and Comparative Examples B1 to B6 were performed according to the following procedure.
1. Preparation of pigment dispersion A pigment, a pigment dispersant, and a solvent are mixed in the following ratio, 200 parts by weight of zirconia beads having a diameter of 0.5 mm are added, and dispersed for 3 hours using a paint shaker (manufactured by Asada Tekko). A pigment dispersion was prepared.

(1) Preparation of red pigment dispersion [Composition of pigment dispersion]
Pigment (CI Pigment Red 254): 4.5 parts by weight Pigment (CI Pigment Red 177): 7.5 parts by weight Pigment (CI Pigment Yellow 150): 3.0 parts by weight Parts / pigment dispersant (Disperbyk 161: trade name, manufactured by BYK Japan, solid content in solvent: 30% by weight): 30.0 parts by weight BDGAC (diethylene glycol monobutyl ether acetate): 55.0 parts by weight

(2) Preparation of green pigment dispersion [Composition of pigment dispersion]
Pigment (CI Pigment Green 36): 7.1 parts by weight Pigment (CI Pigment Yellow 150): 7.9 parts by weight Pigment dispersant (Disperbyk 161: trade name, manufactured by BYK Japan, solvent) (Solid content 30% by weight): 30.0 parts by weight BDGAC (diethylene glycol monobutyl ether acetate): 55.0 parts by weight

(3) Preparation of blue pigment dispersion [Composition of pigment dispersion]
Pigment (CI Pigment Blue 15: 6): 14.1 parts by weight Pigment (CI Pigment Violet 23): 0.9 parts by weight Pigment dispersant (Disperbyk 161: trade name, manufactured by Big Chemie Japan) , 30 wt% solid content in solvent): 30.0 parts by weight BDGAC (diethylene glycol monobutyl ether acetate): 55.0 parts by weight

2. Synthesis of acrylic copolymer (1) Polymerization of acrylic copolymer A reaction vessel equipped with a gas inlet tube, thermometer, condenser, and stirrer was charged with 150 parts by weight of diethylene glycol monobutyl ether acetate (BDGAC) and replaced with nitrogen gas. And heated to 100 ° C. Thereto was added dropwise a mixture of 50 parts by weight of glycidyl methacrylate (GMA), 50 parts by weight of dicyclopentanyl methacrylate (DCPMA) and 10 parts by weight of t-butylperoxy-2-ethylhexanoate over 2 hours.
After completion of the dropwise addition, a GMA / DCPMA copolymer (main chain) solution was obtained by reacting at 100 ° C. for 3 hours.
Similarly, 1-adamantyl methacrylate (ADAMA), cyclohexyl methacrylate (CHMA), isobornyl methacrylate (IBMA), dicyclopentenyl methacrylate (DCPEMA), 2-methyl-2-adamantyl methacrylate (MADAMA), 2-ethyl- The acrylic copolymer was polymerized with 2-adamantyl methacrylate (EADAMA) in the proportions shown in Table 7 below.
For acrylic copolymers j to l for comparative examples, as shown in Table 7, an aromatic ring-containing monomer (benzyl methacrylate; BzMA) and a methyl group-containing monomer (methyl methacrylate; MMA) were used. Polymerization was carried out in the same manner.
In addition, the numerical value in Table 7 shows weight%.
(2) Introduction of ethylenically unsaturated bond To the acrylic copolymer obtained by the above-mentioned method, acrylic acid (AA) in the amount shown in Table 7 and the total amount of monomers contained in the acrylic copolymer (epoxy) Group-containing monomer, alicyclic hydrocarbon-containing monomer, and acrylic acid) per mole part of p-methoxyphenol 0.0004 mole part and N, N-dimethylbenzylamine 0.002 mole part, An acrylic copolymer d having an ethylenically unsaturated bond in the side chain in which a carboxyl group-containing monomer has reacted with an epoxy group by connecting an air introduction tube instead of a nitrogen introduction tube and reacting at 110 ° C. for 10 hours. I was obtained.

3. Preparation of Thermosetting Inkjet Ink for Color Filter As shown in Table 8 below, the acrylic copolymers (a to l), epoxy resins, polyfunctional monomers, thermal polymerization initiators and solvents (BDGAC) obtained above are shown. The resin composition was prepared by blending with the above.
Next, the pigment dispersion and the resin composition are sufficiently mixed, the blending weight ratio (P / V) of the pigment (P) and the solid content (V) other than the pigment is 0.6, and the mixture BDGAC was added so that the solid content was 20% by weight to prepare a thermosetting inkjet ink for color filters.
As the epoxy resin, an alicyclic epoxy resin having two or more epoxy groups in one molecule (product name: EHPE-3150 (shown as EHPE in Table 8), manufactured by Daicel Chemical Industries, Ltd.), and A bisphenol A type novolak epoxy resin (product name: Epicoat 157S70 (shown as Epicoat in Table 8), manufactured by Japan Epoxy Resin Co., Ltd.) was used.
As polyfunctional monomers, dipentaerythritol hexa and pentaacrylate mixture (product name: Aronix M403, pentaacrylate 50-60%, manufactured by Toa Gosei), dipentaerythritol hexa and pentaacrylate mixture (product name: Aronix M405, penta) Acrylate 10-20%, manufactured by Toagosei Co., Ltd.) was used.
As a thermal polymerization initiator, a mixture of glycerin bis (anhydrotrimellitate) monoacetate and an alicyclic dicarboxylic acid anhydride (manufactured by Shin Nippon Rika) was used.

About each obtained thermosetting inkjet ink for color filters, the resin cured film was formed as follows, and surface hardness, adhesiveness, and ITO formation resistance were evaluated. In addition, a colored layer was formed by an inkjet method to evaluate flatness. The evaluation results are also shown in Table 8.
(Formation of cured resin film)
Each inkjet ink was applied onto a 0.7 mm thick glass substrate (Corning Corp., 1737) by spin coating.
Thereafter, prebaking was performed on a hot plate at 90 ° C. for 10 minutes. Then, in a clean oven, heating was performed at 200 ° C. for 30 minutes to perform post baking, and heating was further performed at 240 ° C. for 30 minutes to perform post baking, thereby forming a colored layer.

〔Evaluation methods〕
(1) Surface hardness (pencil hardness)
The pencil hardness of the surface of the color filter layer was evaluated by a “pencil scratch test” in accordance with JIS K 5400-1990 8.4.1.

(2) Adhesiveness The adhesiveness between the colored layer and the substrate was evaluated by the “adhesive cross-cut tape method” according to JIS K 5400-1990 8.5.3. In Table 8, the number of grids remaining without peeling off the color filter layer in 100 grids is shown.

(3) Flatness (Formation of colored layer by inkjet method)
A black matrix pattern having a line width of 20 μm and a film thickness of 2.2 μm is formed on a glass substrate (Corning Corp., 1737) having a thickness of 0.7 mm by a photolithography method using a curable resin composition for black matrix. Formed.
The inkjet ink was adhered to the pixel forming portion partitioned by the black matrix of the substrate by an inkjet method.
Then, it dried under reduced pressure at 10 Torr for 120 seconds, and further pre-baked for 10 minutes on a 90 degreeC hotplate. Thereafter, the substrate was post-baked by heating at 200 ° C. for 30 minutes in a clean oven, and further post-baked by heating at 240 ° C. for 30 minutes to form a pattern of the colored layer on the substrate.
(Surface shape measurement)
The colored layer obtained by the inkjet method as described above was measured using a non-contact type surface shape measuring apparatus New View 6K (manufactured by Zygo), and a surface shape profile was calculated. The lowest part of the surface shape profile of the colored layer was A, the highest part was B, and the flatness was evaluated by the height difference (BA) according to the following evaluation criteria.
[Evaluation criteria]
○: B−A <0.5 μm
Δ: 0.5 μm ≦ B−A <1.0 μm
×: 1.0 μm ≦ BA

(4) Resistance to ITO formation The substrate on which the cured resin film was formed as described above was immersed in isopropyl alcohol for 5 minutes, then dried with isopropyl alcohol vapor, washed, and then set at a substrate set temperature of 200 ° C. An ITO (indium tin oxide) electrode was formed to a thickness of 120 nm under a vacuum of 6 × 10 ⁻³ Torr and evaluated according to the following criteria. Further, the surface roughness (Ra) of the deposited ITO film was measured by AFM. The AFM used was NanoScope IIIa manufactured by Biko Japan.
[Evaluation criteria for ITO resistance]
A: No abnormality such as wrinkles or cracks was observed on the ITO electrode.
Δ: Several abnormalities such as wrinkles and cracks were observed on the ITO electrode.
X: Abnormalities such as wrinkles and cracks were observed on the entire surface of the ITO electrode.

From the results of Table 8, it was confirmed that the ink-jet ink according to the second invention can realize a colored layer having excellent adhesion, surface hardness, and flatness after thermosetting.

Claims (10)

1. A thermosetting inkjet ink for a color filter containing a polyfunctional monomer, a binder resin, a pigment, a pigment dispersant, and a solvent,
   The polyfunctional monomer is a compound having 4 or more ethylenically unsaturated bonds in one molecule, and the binder resin is (A) an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond. And (B) an acrylic copolymer obtained by copolymerizing at least a monomer group containing an alicyclic hydrocarbon-containing monomer having an alicyclic hydrocarbon group and an ethylenically unsaturated bond. Thermosetting inkjet ink for color filters.
2. In the acrylic copolymer, the (A) epoxy group-containing monomer is 20% by weight to 80% by weight in the total copolymer component, and the (B) alicyclic hydrocarbon-containing monomer is in the total copolymer component. 2. The thermosetting inkjet ink for color filter according to claim 1, wherein the thermosetting inkjet ink is 20 wt% to 80 wt%.
3. 2. The thermosetting ink jet for a color filter according to claim 1, wherein in the acrylic copolymer, the (B) alicyclic hydrocarbon-containing monomer has a bridged alicyclic hydrocarbon group. 3. ink.
4. The (B) alicyclic hydrocarbon-containing monomer is isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxy (meth) acrylate, adamantyl (meth) acrylate 1 or more selected from the group consisting of 2-alkyl-2-adamantyl (meth) acrylate, 3-hydroxy-1-adamantyl (meth) acrylate, and 1-perfluoroadamantyl (meth) acrylate The thermosetting inkjet ink for color filters according to claim 1.
5. A thermosetting inkjet ink for a color filter containing a polyfunctional monomer, a binder resin, a pigment, a pigment dispersant, and a solvent,
   The polyfunctional monomer is a compound having 4 or more ethylenically unsaturated bonds in one molecule, and the binder resin is (A) an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond. And (B) an acrylic copolymer obtained by copolymerizing at least a monomer group containing an alicyclic hydrocarbon-containing monomer having an alicyclic hydrocarbon group and an ethylenically unsaturated bond, and the acrylic copolymer A thermosetting inkjet ink for a color filter, comprising an epoxy resin different from the coalescence.
6. The acrylic copolymer is (A) an epoxy group-containing monomer having an epoxy group and an ethylenically unsaturated bond, and (B) an alicyclic hydrocarbon having an alicyclic hydrocarbon group and an ethylenically unsaturated bond. Acrylic system obtained by reacting a carboxyl group-containing monomer (C) having a carboxyl group and an ethylenically unsaturated bond with one or more epoxy groups of a copolymer obtained by copolymerizing at least a containing monomer The thermosetting inkjet ink for a color filter according to claim 5, which is a copolymer.
7. In the acrylic copolymer, the (A) epoxy group-containing monomer is 20% by weight to 80% by weight in the total copolymer component, and the (B) alicyclic hydrocarbon-containing monomer is in the total copolymer component. The thermosetting inkjet ink for a color filter according to claim 5, wherein the thermosetting inkjet ink is 20 wt% to 80 wt%.
8. 6. The thermosetting inkjet for color filter according to claim 5, wherein the (B) alicyclic hydrocarbon-containing monomer has a bridged alicyclic hydrocarbon group in the acrylic copolymer. ink.
9. The (B) alicyclic hydrocarbon-containing monomer is isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxy (meth) acrylate, adamantyl (meth) acrylate 1 or more selected from the group consisting of 2-alkyl-2-adamantyl (meth) acrylate, 3-hydroxy-1-adamantyl (meth) acrylate and 1-perfluoroadamantyl (meth) acrylate The thermosetting inkjet ink for color filters according to claim 5.
10. In the content ratio of the polyfunctional monomer, the acrylic copolymer, and the epoxy resin, the weight ratio of the epoxy resin to the sum of the polyfunctional monomer and the acrylic copolymer (epoxy resin / (polyfunctional Monomer = acrylic copolymer))) is 0.25 to 4, and the weight ratio of the acrylic copolymer to the polyfunctional monomer (acrylic copolymer / polyfunctional monomer) is 0. The thermosetting inkjet ink for a color filter according to claim 5, wherein the thermosetting inkjet ink is a color filter.