JP5286657B2 - Pigment dispersion, inkjet ink for color filter and method for producing the same, color filter, and liquid crystal display device - Google Patents

Description

  The present invention relates to an inkjet ink for a color filter used for forming a cured layer having a predetermined pattern such as a pixel portion (colored layer), a method for producing the inkjet ink, a color filter using the inkjet ink, and The present invention relates to a liquid crystal display device using the color filter.

In recent years, with the development of personal computers, especially portable personal computers, the demand for liquid crystal displays, particularly color liquid crystal displays, has been increasing. However, since this color liquid crystal display is expensive, there is an increasing demand for cost reduction, and in particular, there is a high demand for cost reduction for a color filter having high specific gravity.
In such a color filter, it is usually provided with coloring patterns of three primary colors of red (R), green (G), and blue (B), and electrodes corresponding to the respective pixels of R, G, and B are turned on, By turning it off, 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 color filter layers 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, this process is repeated three times to form R, G, and B color filter layers.
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, a method of forming a colored layer (pixel portion) by spraying ink on the surface of a substrate by an inkjet method has been proposed (Patent Document 1).

JP 59-75205 A JP 2003-113224 A

  In order to form pixels by spraying ink in accordance with an accurate pattern using an inkjet method, straightness and stability when ejected from the ejection head are required. A pigment is often used as the colorant of the color filter. However, when the pigment dispersibility of the color filter ink-jet ink is poor, clogging occurs at the nozzle portion of the ejection head due to aggregation of pigment particles. Therefore, when a pigment is used as the colorant, the pigment dispersibility also affects the ink ejection performance. If the pigment dispersibility is insufficient, the brightness and contrast may be lowered after the color filter is formed.

  In order to improve the pigment dispersibility, a pigment dispersion may be prepared by previously dispersing a pigment with a pigment dispersant, and then a binder component may be mixed with the pigment dispersion to form an ink. However, depending on the pigment dispersant used, there is a problem that wrinkles and cracks tend to occur when a cured film such as a colored layer is prepared using the ink after the ink is prepared. In particular, when a colored layer of a color filter for a display panel such as a liquid crystal display panel is formed using inkjet ink, after forming the colored layer on the substrate, a protective film is formed thereon if necessary, and then Although the transparent electrode film is formed, there arises a problem that wrinkles are generated on the surface of the transparent electrode film. 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 cured film such as a colored layer formed from ink is exposed to such ultra-low pressure and high temperature conditions, the cured film thermally expands and contracts to generate wrinkles, which distorts adjacent layers such as a transparent electrode film. 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.

  On the other hand, Patent Document 2 discloses a photocurable composition containing a polyfunctional alicyclic epoxy compound as a thermal polymerization crosslinking agent. However, Patent Document 2 does not describe anything about using a polyfunctional alicyclic epoxy compound in the pigment dispersion, improving the pigment dispersibility, and preventing wrinkles and cracks in the cured film.

The present invention has been accomplished in view of the above-described actual circumstances, and a first object thereof is a pigment that is excellent in pigment dispersibility and stability over time of pigment dispersion, and is less likely to cause wrinkles and cracks in a cured film after being made into an ink. It is to provide a dispersion.
The second object of the present invention is an inkjet ink for a color filter which is excellent in pigment dispersibility and stability over time, hardly causes wrinkles and cracks in a cured film, and hardly causes wrinkles and cracks in an adjacent layer, and a method for producing the same. Is to provide.
A third object of the present invention is to provide a high-intensity color filter with reduced display defects manufactured using an inkjet ink that achieves the above object.
A fourth object of the present invention is to provide a liquid crystal display device using a color filter manufacturing method that achieves the above object.

The pigment dispersion for inkjet ink used in the color filter according to the present invention is a pigment dispersion containing a pigment, a pigment dispersant, a dispersion auxiliary resin, and a solvent, and the dispersion auxiliary resin is represented by the following general formula (1). an epoxy resin represented, the weight ratio of the solid non-pigment of the pigment dispersion component pigments min for (V) (P) (P / V ratio) is not less than 1.0, the pigment dispersion And at least a binder system, which is a preliminary preparation for preparing an inkjet ink.

(However, R ¹ is a residue obtained by removing active hydrogen in an organic compound having k active hydrogens. N1, n2,... And k is an integer of 1 to 100. A is an oxynorbornene skeleton having a substituent X or an oxycyclohexane skeleton having a substituent X, and is represented by the following formula:

  The pigment dispersion for inkjet ink according to the present invention uses the specific epoxy resin as a dispersion auxiliary resin, so that the dispersibility of the pigment and the temporal stability of the pigment dispersion are improved as compared with the case where only the pigment dispersant is used. In addition, when the ink-jet ink is applied to a color filter after preparation, wrinkles and cracks are less likely to occur in the cured film of the ink. Since the addition of the dispersion auxiliary resin makes it difficult for wrinkles and cracks to occur in the cured film of the ink, it is possible to use pigment dispersants that could not be used because wrinkles were generated in the conventional cured film. There is also a merit that the range to select widens.

  In the pigment dispersion for inkjet ink used in the color filter according to the present invention, the film strength and dispersibility are such that the sum of n1 to nk in the epoxy resin represented by the following general formula (1) is 4 to 30. From the point of view, it is preferable.

  Moreover, in the pigment dispersion liquid for inkjet inks used for the color filter according to the present invention, the dispersion auxiliary resin is preferably 5 to 80 parts by weight with respect to 100 parts by weight of the pigment dispersant. If the dispersion auxiliary resin is less than 5 parts by weight with respect to 100 parts by weight of the pigment dispersant, there is a risk that the effect of improving the pigment dispersibility and the film strength after preparing a cured film as an ink may be insufficient. On the other hand, if the dispersion auxiliary resin exceeds 80 parts by weight with respect to 100 parts by weight of the pigment dispersant, the pigment dispersibility and the pigment dispersion stability over time may be deteriorated.

  In the pigment dispersion for inkjet ink used in the color filter according to the present invention, the solvent is a solvent component having a boiling point of 180 ° C. to 260 ° C. and a vapor pressure at room temperature of 0.5 mmHg or less as a main solvent. It is preferable that it is contained in a proportion of 50% by weight or more, because it is excellent in straightness and stability when ejected from the head when it is made an inkjet ink, and can be dried efficiently.

  The main solvent is ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol dibutyl ether, diethyl adipate, dibutyl oxalate, dimethyl malonate, diethyl malonate, dimethyl succinate, and succinic acid. One or more selected from the group consisting of diethyl is preferable from the viewpoint that when ink jet ink is used, it is excellent in straightness and stability when ejected from the head, and can be dried more efficiently.

  The method for producing an inkjet ink for a color filter according to the present invention includes at least a pigment, a pigment dispersant, and an epoxy resin represented by the following general formula (1) as a main solvent having a boiling point of 180 ° C. to 260 ° C. and at room temperature. Mixing with a dispersion preparation solvent containing at least a solvent component having a vapor pressure of 0.5 mmHg or less, and dispersing to prepare a pigment dispersion;

(However, R ¹ is a residue obtained by removing active hydrogen in an organic compound having k active hydrogens. N1, n2,... And k is an integer of 1 to 100. A is an oxynorbornene skeleton having a substituent X or an oxycyclohexane skeleton having a substituent X, and is represented by the following formula:

It has the process of adjusting so that the mixture ratio of the said main solvent to the solvent whole quantity may be 60 weight% or more by the method in any one of following 1) -3.
1) The obtained pigment dispersion and at least the binder system are mixed with the newly prepared main solvent and / or auxiliary solvent.
2) At least a binder system is prepared by dissolving or dispersing in a newly prepared main solvent and / or auxiliary solvent to prepare a binder solution, and then the binder solution and the pigment dispersion are mixed.
3) At least a binder system is prepared by dissolving or dispersing in a newly prepared main solvent and / or auxiliary solvent to prepare a binder solution, and then the binder solution, the pigment dispersion, and the main solvent and / or auxiliary solvent are mixed. .

The pigment dispersion for inkjet ink used in the color filter according to the present invention is excellent in pigment dispersibility and temporal stability of pigment dispersion due to the action of the dispersion auxiliary resin, and after forming into ink, wrinkles and cracks occur in the cured film. hard. The pigment dispersion for ink-jet ink according to the present invention may cause wrinkles and cracks in the cured film of the ink due to the action of the dispersion assisting resin, even when a pigment dispersant that cannot be used because wrinkles are generated in the conventional cured film. Therefore, there is an advantage that the range of selection of the pigment dispersant is widened.
The inkjet ink for a color filter according to the present invention is excellent in pigment dispersibility and stability over time, hardly causes wrinkles and cracks in a cured film, and hardly causes wrinkles and cracks in an adjacent layer. Moreover, the inkjet ink for color filters which concerns on this invention is excellent in yellowing resistance, and the color purity when applied to a color filter becomes good. Furthermore, since it is excellent in pigment dispersibility, brightness and contrast when applied to a color filter are improved.

Since the color filter according to the invention is manufactured using the inkjet ink that achieves the above object, a high-luminance color filter with reduced display defects can be obtained.
Further, according to the liquid crystal display device according to the present invention, since a color filter with better performance is used, a high-quality liquid crystal display device can be obtained.

  The present invention is described in detail below. In the present invention, light includes electromagnetic waves having wavelengths in the visible and non-visible regions, and radiation, and the radiation includes, for example, microwaves and electron beams. Specifically, it means an electromagnetic wave having a wavelength of 5 μm or less and an electron beam. In the present invention, (meth) acryl means either acryl or methacryl, (meth) acrylate means acrylate or methacrylate, and (meth) acryloyl means acryloyl or Means either methacryloyl.

Hereinafter, the present invention will be described in order of a pigment dispersion, an inkjet ink for a color filter, a manufacturing method thereof, a color filter, and a liquid crystal display device.
1. Pigment dispersion The pigment dispersion for inkjet ink used in the color filter according to the present invention is a pigment dispersion containing a pigment, a pigment dispersant, a dispersion auxiliary resin, and a solvent, and the dispersion auxiliary resin is represented by the following general formula ( It is an epoxy resin represented by 1).

(However, R ¹ is a residue obtained by removing active hydrogen in an organic compound having k active hydrogens. N1, n2,... And k is an integer of 1 to 100. A is an oxynorbornene skeleton having a substituent X or an oxycyclohexane skeleton having a substituent X, and is represented by the following formula:

  The pigment dispersion for inkjet ink according to the present invention uses the specific epoxy resin as a dispersion auxiliary resin, so that the dispersibility of the pigment and the temporal stability of the pigment dispersion are improved as compared with the case where only the pigment dispersant is used. In addition, when the ink-jet ink is applied to a color filter after preparation, wrinkles and cracks are less likely to occur in the cured film of the ink. The pigment dispersion for ink-jet ink according to the present invention may cause wrinkles and cracks in the cured film of the ink due to the action of the dispersion assisting resin, even when a pigment dispersant that cannot be used because wrinkles are generated in the conventional cured film. Therefore, there is an advantage that the range of selection of the pigment dispersant is widened.

The pigment dispersion is a pigment composition having a high P / V ratio (pigment content in the composition / solid content other than the pigment in the composition), which is preliminarily prepared in the stage before preparing the inkjet ink described later. It is. Specifically, the P / V ratio is 1.0 or more. By mixing the pigment dispersion and at least a binder system, it is possible to prepare an ink-jet ink having high pigment dispersibility.
Hereinafter, components used in the pigment dispersion according to the present invention will be described.

(Pigment)
The pigment as the colorant can be selected from any organic colorant and inorganic colorant according to the color required by the pixel (pixel portion) such as R, G, B, and the light shielding portion. . As the organic colorant, for example, dyes, organic pigments, natural pigments, and the like can be used. Moreover, as an inorganic coloring agent, an inorganic pigment, an extender pigment, etc. can be used, for example. Among these, organic pigments are preferably used because they have high color developability and high heat resistance. As organic pigments, for example, compounds classified as Pigments in the Color Index (CI; published by The Society of Dyers and Colorists), specifically, the following Color Index (CI) numbers are attached. Can be mentioned.

  CI Pigment Yellow 1, CI Pigment Yellow 3, CI Pigment Yellow 12, CI Pigment Yellow 13, CI Pigment Yellow 14, CI Pigment Yellow 15, CI Pigment Yellow 16, CI Pigment Yellow 17, CI Pigment Yellow 20, CI Pigment Yellow 24, CI Pigment Yellow 31, CI Pigment Yellow 55, CI Pigment Yellow 60, CI Pigment Yellow 61, CI Pigment Yellow 65, CI Pigment Yellow 71, CI Pigment Yellow 73, CI Pigment Yellow 74, CI Pigment Yellow 81, CI Pigment Yellow 83, CI Pigment Yellow 93, CI Pigment Yellow 95, CI Pigment Yellow 97, CI Pigment Yellow 98, CI Pigment Yellow 100, CI CI Pigment Yellow 101, CI Pigment Yellow 104, CI Pigment Yellow 106, CI Pigment Yellow 108, CI Pigment Yellow 109, CI Pigment Yellow 110, CI Pigment Yellow 113, CI Pigment Yellow 114, CI Pigment Yellow 116, CI Pigment Yellow 117, CI Pigment Yellow 119, CI Pigment Yellow 120, CI Pigment Yellow 126, CI Pigment Yellow 127, CI Pigment Yellow 128, CI Pigment Yellow 129, CI Pigment Yellow 138, CI Pigment Yellow 139, CI Pigment Yellow 150, CI Pigment Yellow 151, CI Pigment Yellow 152, CI Pigment Yellow 153, CI Pigment Yellow 154, CI Pigment .... DOO Yellow 155, C.I Pigment Yellow 156, C.I Pigment Yellow 166, C.I Pigment Yellow 168, C.I Pigment Yellow 175;

  CI Pigment Orange 1, CI Pigment Orange 5, CI Pigment Orange 13, CI Pigment Orange 14, CI Pigment Orange 16, CI Pigment Orange 17, CI Pigment Orange 24, CI Pigment Orange 34, CI Pigment Orange 36, CI Pigment Orange 38, CI Pigment Orange 40, CI Pigment Orange 43, CI Pigment Orange 46, CI Pigment Orange 49, CI Pigment Orange 51, CI Pigment Orange 61, CI Pigment Orange 63, CI Pigment Orange 64, CI Pigment Orange 71, CI Pigment Orange 73; CI Pigment Violet 1, CI Pigment Violet 19, CI Pigment Violet 23, CI Pigment Violet 29, CI Pigment Buy Olet 32, C.I. pigment violet 36, C.I. pigment violet 38;

  CI Pigment Red 1, CI Pigment Red 2, CI Pigment Red 3, CI Pigment Red 4, CI Pigment Red 5, CI Pigment Red 6, CI Pigment Red 7, CI Pigment Red 8, CI Pigment Red 9, CI Pigment Red 10, CI Pigment Red 11, CI Pigment Red 12, CI Pigment Red 14, CI Pigment Red 15, CI Pigment Red 16, CI Pigment Red 17, CI Pigment Red 18, CI Pigment Red 19, CI Pigment Red 21, CI Pigment Red 22, CI Pigment Red 23, CI Pigment Red 30, CI Pigment Red 31, CI Pigment Red 32, CI Pigment Red 37, CI Pigment Red 38, CI Pigment Red 40, CI Pigment Red 41, CI Pigment Red 42, CI Pigment Red 48: 1, CI Pigment Red 48: 2, CI Pigment Red 48: 3, CI Pigment Red 48: 4, CI Pigment Red 49: 1, CI Pigment Red 49: 2, CI CI Pigment Red 50: 1, CI Pigment Red 52: 1, CI Pigment Red 53: 1, CI Pigment Red 57, CI Pigment Red 57: 1, CI Pigment Red 57: 2, CI Pigment Red 58: 2, CI Pigment Red 58 : 4, CI Pigment Red 60: 1, CI Pigment Red 63: 1, CI Pigment Red 63: 2, CI Pigment Red 64: 1, CI Pigment Red 81: 1, CI Pigment Red 83, CI Pigment Red 88, CI Pigment Red 90: 1, CI pigmentless 97, CI Pigment Red 101, CI Pigment Red 102, CI Pigment Red 104, CI Pigment Red 105, CI Pigment Red 106, CI Pigment Red 108, CI Pigment Red 112, CI Pigment Red 113, CI Pigment Red 114, CI Pigment Red 122, CI Pigment Red 123, CI Pigment Red 144, CI Pigment Red 146, CI Pigment Red 149, CI Pigment Red 150, CI Pigment Red 151, CI Pigment Red 166, CI Pigment Red 168, CI Pigment Red 170, CI Pigment Red 171, CI Pigment Red 172, CI Pigment Red 174, CI Pigment Red 175, CI Pigment Red 176, CI Pigment Red 77, CI Pigment Red 178, CI Pigment Red 179, CI Pigment Red 180, CI Pigment Red 185, CI Pigment Red 187, CI Pigment Red 188, CI Pigment Red 190, CI Pigment Red 193, CI Pigment Red 194, CI Pigment Red 202, CI Pigment Red 206, CI Pigment Red 207, CI Pigment Red 208, CI Pigment Red 209, CI Pigment Red 215, CI Pigment Red 216, CI Pigment Red 220, CI Pigment Red 224, CI Pigment Red 226, CI Pigment Red 242, CI Pigment Red 243, CI Pigment Red 245, CI Pigment Red 254, CI Pigment Red 255, CI Pigment Red . 64, C.I Pigment Red 265;

  CI Pigment Blue 15, CI Pigment Blue 15: 3, CI Pigment Blue 15: 4, CI Pigment Blue 15: 6, CI Pigment Blue 60; CI Pigment Green 7, CI Pigment Green 36; CI Pigment Brown 23, CI Pigment Brown 25 CI pigment black 1, pigment black 7.

  Specific examples of the inorganic pigment or extender pigment include titanium oxide, barium sulfate, calcium carbonate, zinc white, lead sulfate, yellow lead, zinc yellow, red rose (red iron oxide (III)), cadmium red, ultramarine blue, Examples include bitumen, chromium oxide green, cobalt green, amber, titanium black, synthetic iron black, and carbon black. In this invention, a pigment can be used individually or in mixture of 2 or more types.

  When forming the pattern of the light-shielding part on the substrate of the color filter using the ink-jet ink of the present invention, a black pigment having a high light-shielding property is blended in the ink-jet ink. As the black pigment having a high light shielding property, for example, an inorganic colorant such as carbon black or iron trioxide, or an organic colorant such as cyanine black can be used.

In the pigment dispersion for inkjet ink used in the color filter according to the present invention, the dispersion average particle diameter of the pigment is preferably 100 nm or less. In such a case, the pigment dispersibility and the pigment dispersion stability over time are good, and the brightness and contrast are improved when the ink-jet ink is applied to a color filter after preparation. Also, the ejection stability when ink is used is improved.
Here, the dispersion average particle diameter of the pigment is measured at 23 ° C. by a dynamic light scattering method (Doppler scattered light analysis) with a particle size distribution meter (for example, MICROTRAC UPA MODEL 9230 manufactured by Nikkiso Co., Ltd.). Further, the average particle diameter here is a 50% average particle diameter, that is, a volume-based median diameter.
In the pigment dispersion according to the present invention, the pigment content is preferably 5 to 40% by weight based on the total amount of the pigment dispersion including the solvent, from the viewpoint of pigment dispersibility and pigment dispersion aging stability. More preferably, it is 10 to 30% by weight.

(Pigment dispersant)
The pigment dispersant is blended to disperse the pigment satisfactorily. Examples of the pigment dispersant that can be used include cationic, anionic, nonionic, amphoteric, silicone, and fluorine surfactants. Among the surfactants, polymer surfactants (polymer dispersants) as exemplified below are preferable.
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.

Further, as commercially available pigment dispersants, Disperbyk-110, 116, 130, 140, 160, 161, 162, 163, 164, 165, 166, 169, 170, 171, 174, 180, 182, 183, 184, 185, 2000, 2001, 2020, 2050, 2070, 2090, 2091, 2095, 2096, 2150, etc. (above, manufactured by BYKchemie); EFKA-4008, 4009, 4010, 4047, 4050, 4055, 4080, 4400, 4401, 4402, 4403, 4406, 4500, 4510, 4520, 4530, 4540, 4550, 4560, 4702, 4747, 5010, 5044, 5054, 5055, 5063, 5064, 5065, 5066, 5071, 5207, 244, 5744 and the like (manufactured by Efka CHEMICALS); , 32500, 32550, 32600, 33500, 34750, 35100, 35200, 36000, 36600, 37500, 38500, 39000, etc. (manufactured by Nihon Lubrizol Co., Ltd.); # 7004, # 1830, # 1850, # 1860, DA-400, DA703-50, DA-705, DA-725, etc. Or more, manufactured by Kusumoto Kasei Co., Ltd.); Adisper PB-821, PB-822, PB-824, PB-827, and the like (Ajinomoto Fine-Techno Co., Ltd.), and the like.
In the pigment dispersion of the present invention, the content of the pigment dispersant is preferably 5 to 100 parts by weight, more preferably 100 parts by weight of the pigment, from the viewpoint of pigment dispersibility and pigment dispersion stability over time. 10 to 80 parts by weight.

(Dispersion auxiliary resin)
In the pigment dispersion according to the present invention, an epoxy resin represented by the following formula (1) is used as a dispersion auxiliary resin in addition to the pigment dispersant.

(However, R ¹ is a residue obtained by removing active hydrogen in an organic compound having k active hydrogens. N1, n2,... And k is an integer of 1 to 100. A is an oxynorbornene skeleton having a substituent X or an oxycyclohexane skeleton having a substituent X, and is represented by the following formula:

  Here, the dispersion auxiliary resin has a function of enhancing the action of the pigment dispersant and has an auxiliary function of improving the pigment dispersibility as compared with the case of using only the pigment dispersant. The dispersion auxiliary resin used in the present invention enhances the action of various pigment dispersants, has a function capable of achieving high pigment dispersibility, and has a highly reactive terminal epoxy group, and thus has high reactivity. It has a function as a curable resin. Therefore, even when using only the pigment dispersant, it is possible to prevent the occurrence of wrinkles and cracks even when used with a pigment dispersant that causes wrinkles and cracks in the cured film. Moreover, since the said specific epoxy resin has an alicyclic skeleton, yellowing-proof property improves compared with the case where it has an acrylic skeleton which has a double bond, and an aromatic ring skeleton.

R ¹ in the above formula (1) is a residue obtained by removing active hydrogen in an organic compound having active hydrogen. Examples of the organic substance having active hydrogen which is a precursor thereof include alcohols, phenols, and carboxylic acids. , Amines, thiols and the like. The alcohol may be a monohydric alcohol or a polyhydric alcohol.

  For example, aliphatic alcohol such as methanol, ethanol, propanol, butanol, pentanol, hexanol and octanol, aromatic alcohol such as benzyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, 1 , 3-butanediol, 1,4-butanediol, pentanediol, 1,6-hexanediol, neopentyl glycol, hydroxypivalic acid neopentyl glycol ester, cyclohexanedimethanol, glycerin, diglycerin, polyglycerin, trimethylolpropane And polyhydric alcohols such as trimethylolethane, pentaerythritol and dipentaerythritol.

Examples of phenols include phenol, cresol, catechol, pyrogallol, hydroquinone, hydroquinone monomethyl ether, bisphenol A, bisphenol F, 4,4′-dihydroxybenzophenone, bisphenol S, phenol resin, cresol novolac resin, and the like.
Carboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, fatty acids of animal and vegetable oils, fumaric acid, maleic acid, adipic acid, dodecanedioic acid, trimellitic acid, pyromellitic acid, polyacrylic acid, phthalic acid, isophthalic acid, terephthalic acid There are acids.
Also included are compounds having both a hydroxyl group and a carboxylic acid, such as lactic acid, citric acid, and oxycaproic acid.

Examples of amines include monomethylamine, dimethylamine, monoethylamine, diethylamine, propylamine, monobutylamine, dibutylamine, pentylamine, hexylamine, cyclohexylamine, octylamine, dodecylamine, 4,4′-diaminodiphenylmethane, isophoronediamine, There are toluenediamine, hexamethylenediamine, xylenediamine, diethylenetriamine, triethylenetetramine, ethanolamine and the like.
Examples of thiols include mercaptos such as methyl mercaptan, ethyl mercaptan, propyl mercaptan, and phenyl mercaptan, mercaptopropionic acid or polyvalent alcohol esters of mercaptopropionic acid, such as ethylene glycol dimercaptopropionic acid ester, trimethylolpropane trimercaptopropionic acid, Examples include pentaerythritol tetramercaptopropionic acid.

In addition, other active hydrogen-containing compounds include polyvinyl alcohol, polyvinyl acetate partial hydrolyzate, starch, cellulose, cellulose acetate, cellulose acetate butyrate, hydroxyethyl cellulose, acrylic polyol resin, styrene allyl alcohol copolymer resin, and styrene-maleic acid. Examples include acid copolymer resins, alkyd resins, polyester polyol resins, polyester carboxylic acid resins, polycaprolactone polyol resins, polypropylene polyols, and polytetramethylene glycol.
The compound having active hydrogen may have an unsaturated double bond in its skeleton, and specific examples thereof include allyl alcohol, acrylic acid, methacrylic acid, 3-cyclohexenemethanol, tetrahydrophthalic acid, and the like. is there.
Any compounds having these active hydrogens can be used, and two or more of them may be mixed.

In the general formula (1), n1, n2... Nk are each 0 or an integer of 1 to 100, and the sum thereof is 1 to 100. When the sum exceeds 100, there is a possibility that a problem may occur in productivity and storage stability of the dispersion. k represents an integer of 1 to 100. n1, n2... nk are each 2 to 10, more preferably 3 to 6, and k is preferably 2 to 6. The sum of n1 to nk is preferably 4 to 30. When the sum of n1 to nk is less than 4, the crosslink density after curing becomes low and it is difficult to obtain sufficient film strength. On the other hand, if the sum of n1 to nk is more than 30, there is a tendency that it is difficult to dissolve in a solvent, and the handling property of the material may be deteriorated. Further, 4 to 20 is preferable from the viewpoint of film strength and dispersibility. The k A's may be the same or different.
Moreover, as A, it is more preferable that it is a structure of Formula (3).

  Among the substituents X of A in the general formula (1), it is essential that at least one structure of the formula (4) is contained in the resin, but the more is more preferable. In particular, the smaller the structure of formula (6), the better. That is, in the present invention, the substituent X mainly has the structure of the formula (4).

  The epoxy resin represented by the above formula (1) used in the present invention is a 5-vinylbicyclo [2.2.1] using the compound having active hydrogen as an initiator, as in JP-B-7-119270. Polyether resin obtained by ring-opening polymerization of a mixture of hept-2-ene-2-oxide or 4-vinylcyclohexene-1-oxide and a compound having one epoxy group, that is, a vinyl group side chain and norbornene It is produced by epoxidizing a polyether resin having a skeleton or vinyl group side chain and a cyclohexane skeleton with peracetic acid or hydrogen peroxide.

  As a commercial item of the epoxy resin represented by the above formula (1) used in the present invention, Daicel Chemical Industries, Ltd., EHPE3150 (the sum of n1 to nk is an average of 15) can be mentioned as a suitable one.

  The dispersion auxiliary resin is preferably 5 to 80 parts by weight, and more preferably 10 to 60 parts by weight with respect to 100 parts by weight of the pigment dispersant. If the dispersion auxiliary resin is less than 5 parts by weight with respect to 100 parts by weight of the pigment dispersant, there is a risk that the effect of improving the pigment dispersibility and the film strength after preparing a cured film as an ink may be insufficient. On the other hand, if the dispersion auxiliary resin exceeds 80 parts by weight with respect to 100 parts by weight of the pigment dispersant, the pigment dispersibility and the pigment dispersion stability over time may be deteriorated.

(solvent)
The pigment dispersion according to the present invention contains a solvent as a solvent for preparing the dispersion. The solvent used in the pigment dispersion is also important in improving the pigment dispersibility, but on the other hand, it is necessary to consider the performance as a solvent when the pigment dispersion is used as an inkjet ink.
The pigment dispersion of the present invention has a boiling point of 180 ° C. to 260 ° C., particularly 210 ° C. to 260 ° C., and a vapor pressure at room temperature (especially in the range of 18 ° C. to 25 ° C.) of 0.5 mmHg or less, particularly 0.1 mmHg. The following solvent components are used as the main solvent, and such main solvent is preferably blended in a proportion of 50% by weight or more based on the total amount of the dispersion preparation solvent.

  A solvent component having a boiling point of 180 ° C. to 260 ° C. and a vapor pressure at room temperature of 0.5 mmHg or less has an appropriate drying property and evaporation property. For this reason, if a single solvent or mixed solvent containing such a solvent component in a high blending ratio is used, the inkjet ink does not dry rapidly at the nozzle tip of the discharge head, causing a sudden increase in viscosity or clogging of the ink. Without adversely affecting the straightness and stability of the discharge. At the same time, since the drying proceeds at an appropriate speed after spraying on the surface to be ejected, the ink becomes familiar with the surface to be coated and the surface of the coating film becomes horizontal and smooth, followed by natural drying or a general heating process. The ink can be dried quickly and completely. Compared to the case of using a wetting agent or a solvent having a very high boiling point, there is less possibility that the solvent remains in the coating film after the drying step. The solvent component used as the main solvent may be one kind or a mixed solvent of two or more kinds as long as it has the above boiling point and vapor pressure.

In addition, the surface tension of the main solvent at 23 ° C. is preferably 28 mN / m or more from the viewpoint that the outflow of ink to the sparse ink portion during patterning can be reduced. In addition, when a main solvent is 2 or more types of mixed solvents, it is preferable to have the said surface tension as the whole mixed solvent.
By forming a wettability variable layer on the surface of the substrate and exposing it, an ink-philic region is formed on a portion of the substrate where the ink layer is to be formed, and the inkjet ink of the present invention is selectively applied to the ink-philic region by the inkjet method. When adhering to the liquid, the standard solution shown in the wettability test specified in JIS K6768 is used as the main solvent, and the contact angle (θ) after 30 seconds is measured after contact with the liquid droplets. A test in which the contact angle with respect to the surface of a test piece having a critical surface tension of 30 mN / m determined by the graph of 25 ° or more, preferably 30 ° or more, and the critical surface tension determined by the same measurement method is 70 mN / m. You may select and use what the contact angle with respect to the surface of a piece shows 10 degrees or less.
When an ink is prepared using a solvent that exhibits the above behavior with respect to wettability, the ink exhibits a large repellent property with respect to the surface of the wettability variable layer before changing the wettability of the wettability variable layer described later. After changing the wettability of the wettability variable layer to increase the hydrophilicity, the wettability variable layer shows a great affinity for the surface of the wettability variable layer. Therefore, the difference between the wettability of the ink with respect to the ink-philic region formed by selectively exposing a part of the surface of the wettability variable layer and the wettability of the ink repellent region with respect to the surrounding region can be increased. As a result, the ink sprayed onto the ink-philic area by the ink jet method spreads evenly to every corner of the ink-philic area. As a result, a fine and precise ink layer pattern can be formed by the inkjet method.

  Here, the test piece having the above characteristics with respect to the critical surface tension may be formed of any material. Examples of test pieces having a critical surface tension of 30 mN / m include, for example, polymethyl methacrylate, polyvinyl chloride, polyvinylidene chloride, polyethylene terephthalate having a smooth surface, and the polymer or surface modifier applied on a smooth glass surface. The above test can be actually performed from among those, and the corresponding one can be selected. Moreover, as a test piece which shows critical surface tension 70mN / m, the said test is actually performed from what apply | coated nylon, the glass surface which hydrophilized, etc., and the applicable thing can be selected.

The main solvent can be selected from the following solvents: glycol ethers such as ethylene glycol monohexyl ether and diethylene glycol monomethyl ether; glycols such as ethylene glycol monobutyl ether acetate and diethylene glycol monomethyl ether acetate Ether esters; aliphatic or aromatic esters such as ethyl acetate, propyl benzoate; dicarboxylic acid diesters such as diethyl carbonate; alkoxycarboxylates such as methyl 3-methoxypropionate; Ketocarboxylic esters such as: ethanol, isopropanol, alcohols such as phenol, or phenols; aliphatic or aromatic such as diethyl ether, anisole Ethers; alkoxy alcohols such as 2-ethoxyethanol and 1-methoxy-2-propanol; glycol oligomers such as diethylene glycol and tripropylene glycol; alkoxy alcohol esters such as 2-ethoxyethyl acetate; acetone and methyl Ketones such as isobutyl ketone.
Further, as the main solvent, it is preferable to use a solvent that does not contain a hydroxyl group from the viewpoint of the temporal stability when ink is used.

  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, succinate Examples thereof include dimethyl acid and diethyl succinate. These solvents are preferable not only because they satisfy the requirements of a boiling point of 180 ° C. to 260 ° C. and a vapor pressure at room temperature of 0.5 mmHg or less, but also have no hydroxyl group in the molecule. Furthermore, 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.

  The above-mentioned solvent exemplified as a preferable example uses a standard solution shown in the wettability test specified in JIS K6768, measures the contact angle (θ) 30 seconds after contacting a droplet, The contact angle with respect to the surface of the test piece having a critical surface tension of 30 mN / m determined by the above is 25 ° or more, and the contact angle with respect to the surface of the test piece having a critical surface tension of 70 mN / m determined by the same measurement method is 10 Also meets the requirement to show below. Therefore, these solvents are mainly used when a wettability variable layer is provided on the surface of a substrate for exposure, and ink jet ink is selectively attached using a difference in wettability between an exposed portion and an unexposed portion. It can be suitably used as a solvent.

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 eliminate moisture, it is preferable to prepare a pigment dispersion using an organic solvent having low miscibility with water. From such a viewpoint, the solubility of the solvent for preparing the pigment dispersion 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 main solvents mentioned as specific examples, diethylene glycol monobutyl ether acetate does not have a hydroxyl group, and the solubility in 100 parts by weight of water at a liquid temperature of 20 ° C. is low at 6.5 parts by weight. It is particularly preferable since it exhibits the property.

  The solvent may contain a solvent component (sub-solvent) other than the main solvent from the viewpoint of pigment dispersibility and performance after ink preparation. However, even in that case, it is preferable to use the main solvent having the above boiling point and vapor pressure in a proportion of 50% by weight or more based on the total amount of the solvent. When the proportion of the main solvent is 50% by weight or more of the total amount of the solvent, when the pigment dispersion is used to make an inkjet ink described later, the proportion of the main solvent can be easily increased, and the drying property and evaporation suitable for the inkjet method are used. Thus, the intermittent ejection stability of the ink jet is improved.

As a secondary solvent used in combination with the above main solvent, a solvent component having a boiling point of 130 ° C. or higher and lower than 180 ° C., it is difficult to form a thick film portion at the end and a good coating film with reduced surface unevenness is obtained. It is preferable because it is easily formed. The sub-solvent having such a boiling point has a boiling point appropriately lower than that of the main solvent. Therefore, when combined in an appropriate amount, the solute does not dry quickly at the nozzle tip of the inkjet head, but the solute flows when the ink layer is dried. It is a component that makes it possible to control the drying rate and appropriately adjust the drying rate. The solvent component used as the auxiliary solvent may be used alone or in combination of two or more as long as it has the above boiling point.
Especially, it is preferable that the boiling point of each solvent component used for a subsolvent is 140 to 180 degreeC, and it is especially preferable that it is 140 to 175 degreeC.

  Moreover, it is preferable that the viscosity at 23 degreeC of the said auxiliary solvent is 0.5-6 mPa * s. In such a case, it is possible to appropriately reduce the viscosity of the ink without impairing the effect of the main solvent by including the sub-solvent, and as a result of improving the wetting and spreading property of the ink itself, The landed ink droplets are easily spread all over the corners of the entire ink layer formation region. As a result, even when the substrate is diversified, it is possible for the landed ink to spread evenly to the portion near the light-shielding portion, and to prevent pixel color loss and luminance reduction. There is also a method of landing ink toward the edge of the region in order to adhere the ink to the corner of the region, but this method may cause the ink to flow out from the gap of the light shielding portion. On the other hand, it is a more desirable method that the ink per se is spread by the ink itself as in the present invention without causing the ink to flow out. The viscosity of the secondary solvent at 23 ° C. is preferably 0.5 to 3 mPa · s. When two or more sub-solvents are used in combination, they are preferably used as long as the viscosity of the mixed solvent is within the above range even if it is outside the above range. Here, the viscosity at 23 ° C. in the present invention can be measured by a rotational vibration type viscometer (for example, a rotational vibration type viscometer Viscomate VM-1G manufactured by Yamaichi Electronics Co., Ltd.).

  If the surface tension of the secondary solvent at 23 ° C. is 35 mN / m or less, it can be suitably used. In particular, when the surface tension of the sub-solvent at 23 ° C. is 28 mN / m or less, the surface tension can be appropriately reduced without hindering the effect of the main solvent, and the ink itself is wetted. Since the spreadability is improved, the landed ink droplets are easily wetted and spread to every corner of the entire ink layer formation region. Here, the surface tension at 23 ° C. in the present invention can be measured by a surface tension meter (Wilhelmi method) (for example, an automatic surface tension meter CBVP-Z manufactured by Kyowa Interface Science Co., Ltd.).

Moreover, as said subsolvent, what is necessary is just a solvent which has the said boiling point, However, It is preferable to select and use the solvent excellent in compatibility with a main solvent suitably.
Specific examples of the auxiliary solvent include ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol dipropyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl. Polyhydric alcohol ethers such as ether, propylene glycol monobutyl ether, diethylene glycol methyl ethyl ether, glycol ethers such as diethylene glycol dimethyl ether, and glycerin ethers such as glycerin 1,3-dimethyl ether; ethylene glycol monomethyl ether acetate, ethylene glycol Monoethyl ether acetate, ethylene glycol Glycol esters including glycol ether esters such as propyl monopropyl ether acetate, ethylene glycol monomethoxymethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and glycerin esters such as glycerin 1-monoacetate Polyhydric alcohol esters; carboxylic acids such as isovaleric acid, isobutyric acid, propionic acid, butyric acid; ethyl isovalerate, hexyl formate, amyl acetate, isoamyl acetate, cyclohexyl acetate, ethyl lactate, methyl lactate, isoamyl propionate, Aliphatic esters such as butyl propionate, butyl butyrate, tributyl citrate, dimethyl oxalate; alkoxy such as ethyl 3-ethoxypropionate Rubonic acid esters; ketocarboxylic acid esters such as methyl acetoacetate; n-amyl alcohol, isoamyl alcohol, 2-ethylbutanol, glycidol, n-hexanol, 2-methylcyclohexanol, 4-methyl-2-pentanol, Monohydric alcohols such as 2-octanol, cyclohexanol, 2-heptanol, 3-heptanol, n-heptanol; ethers such as diisoamyl ether and 1,8-cineol; ethyl-n-butyl ketone, diisobutyl ketone , Ketones such as di-n-propyl ketone, methylcyclohexanone, methyl-n-hexyl ketone, acetylacetone and diacetone alcohol; alkanes such as nonane and decane.

Among them, ethers including polyhydric alcohol ethers such as glycol ethers and glycerin ethers, polyhydric alcohol esters such as glycol esters and glycerin esters, aliphatic esters, alkoxycarboxylic esters, ketocarboxylic acids It is preferable to use one or more selected from the group consisting of esters including esters. In the case of using esters and ethers as described above, there is an advantage that it is easy to maintain good ink stability even when a highly reactive resin is used for the binder component or the like. Also, when glycol ethers or glycol esters are used, the wettability with respect to the glass substrate is improved, and the ink layer formation region is easily spread to every corner, which is effective in preventing color loss of pixels. .
Among these co-solvents, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, diethylene glycol methyl ethyl Ether, diethylene glycol dimethyl ether, glycerin 1,3-dimethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monomethoxymethyl ether, propylene glycol monomethyl ether acetate From methyl acetoacetate, hexyl formate, cyclohexyl acetate, ethyl lactate, isoamyl propionate, butyl propionate, butyl butyrate, tributyl citrate, dimethyl oxalate, ethyl 3-ethoxypropionate, diisoamyl ether, and 1,8-cineol One or more solvents selected from the group consisting of

  The pigment dispersion according to the present invention is prepared by using the dispersion preparation solvent as described above usually at a ratio of 60 to 85% by weight with respect to the total amount of the pigment dispersion containing the solvent. When the amount of the solvent is too small, the viscosity is increased, and the pigment dispersibility and the pigment dispersion stability with time are likely to be lowered. Moreover, when there are too many solvents, pigment concentration will fall and it may be difficult to achieve the target chromaticity coordinates after preparation of the ink.

(Method for producing pigment dispersion)
The pigment dispersion according to the present invention comprises the above-mentioned pigment, pigment dispersant, the above-mentioned dispersion auxiliary resin, and other components as necessary, mixed in an organic solvent in an arbitrary order, and kneader, roll mill, attritor, super A pigment dispersion can be prepared by dispersing using a known disperser such as a mill, dissolver, homomixer, or sand mill.
When dispersing the pigment, it is preferable to add zirconia beads or the like as appropriate and perform dispersion for several hours using a paint shaker (manufactured by Asada Steel Corporation) or the like. Moreover, it is preferable to filter with a 5.0 micron membrane filter after dispersion.
In this way, a pigment dispersion having excellent pigment particle dispersibility is obtained. This pigment dispersion is used as a preliminary preparation for preparing an inkjet ink for a color filter having excellent pigment dispersibility.

2. Ink-jet ink for color filter The ink-jet ink for color filter according to the present invention is an ink-jet ink for color filter containing a pigment, a pigment dispersant , a dispersion assisting resin, a binder system, and a solvent. It is an epoxy resin represented by Formula (1).

(However, R ¹ is a residue obtained by removing active hydrogen in an organic compound having k active hydrogens. N1, n2,... And k is an integer of 1 to 100. A is an oxynorbornene skeleton having a substituent X or an oxycyclohexane skeleton having a substituent X, and is represented by the following formula:

  The inkjet ink for a color filter according to the present invention is characterized in that after preparing the pigment dispersion according to the present invention, at least a binder system is added.

  The inkjet ink for a color filter according to the present invention improves the dispersibility of the pigment and the temporal stability of the pigment dispersion by using the specific epoxy resin as a dispersion auxiliary resin. Contrast is improved. Further, since the specific epoxy resin has an alicyclic skeleton, yellowing resistance is improved as compared with the case of having an acrylic skeleton having a double bond or an aromatic ring skeleton, and as a result, a color filter. The color purity when applied to is improved.

  Further, the inkjet ink for a color filter according to the present invention uses the specific epoxy resin as a dispersion auxiliary resin, so that the cured film of the ink is less likely to be wrinkled or cracked, and the adjacent layer such as the transparent electrode film is wrinkled. It is difficult to cause cracks. That is, it is estimated that the inkjet ink for color filters which concerns on this invention can form a coating film with very small thermal expansion and contraction by containing the said specific epoxy resin. Even if the coating film after curing formed by the ink-jet ink is exposed to a heat treatment in a thermosetting process or a process before and after that, or a high temperature environment after becoming a product, The problem of coating film defects such as cracks, deterioration of adhesion, or wrinkles of adjacent layers laminated on the coating film does not occur.

  In particular, in the case of forming a colored layer such as a pixel of a color filter for a display panel such as a liquid crystal display panel or a light shielding portion using the inkjet ink according to the present invention, in the step of forming a transparent electrode film or an alignment film The underlying pixel is exposed to high temperature and ultra-low pressure due to vacuum, but even in this case, the pattern of the pixel portion is less likely to thermally expand and contract, so the adjacent layers such as the transparent electrode film are distorted. The problem of flaws on the surface and disconnection does not occur. Therefore, display defects are reduced in the color filter and the display panel formed using the ink-jet ink according to the present invention.

  Among the components contained in the inkjet ink according to the present invention, the pigment, the pigment dispersant, the specific dispersion auxiliary resin, and the solvent can be the same as those used for the pigment dispersion, The description here is omitted.

(Binder system)
The ink-jet ink used in the present invention contains a binder system in order to impart film formability and adhesion to the coated surface. In the present invention, the binder system is a liquid mixture contained in the ink for adhering and fixing the pixels at a predetermined position. In addition to the curable compound having reactivity in the subsequent curing process, It also includes compounds that are not themselves reactive.

  Since the ink used in the present invention is an ink used in an ink jet system, in order to form a predetermined pattern, it can be formed by selectively adhering the ink only to a predetermined pattern formation region and solidifying it, It is not necessary to form a pattern by performing exposure and development. Therefore, as a binder system, it is not always necessary to use a photo-curable binder system that can be exposed and developed, and a non-curable thermoplastic resin composition may be used, but a binder system that includes a curable resin is used. It is preferable to use it because it imparts sufficient hardness to the cured film.

Examples of the curable binder system include a thermosetting binder system including a thermosetting resin that can be polymerized and cured by heating, and a photocurable resin that can be polymerized and cured by visible light, ultraviolet light, electron beam, and the like. It is possible to use a photocurable binder system that contains both a thermosetting binder and a photocurable binder.
In this invention, it is preferable that the said binder system has only thermosetting as sclerosis | hardenability and is non-photocurable. The ink according to the present invention does not necessarily need to use a photocurable binder that can be exposed and developed as described above. When the photocurable property is not used, special incidental equipment such as a light irradiation device is used. There is an advantage that it becomes unnecessary and productivity is high. In addition, when only a thermosetting binder system such as an epoxy resin is used, the blending weight of the pigment (P) and the solid content (V) other than the pigment due to a synergistic effect with the specific epoxy resin used as the dispersion auxiliary resin. Even when the ratio (P / V ratio) is higher, the film physical properties of the pixel are improved, such as the solvent resistance and adhesion of the cured film, and the occurrence of wrinkles and cracks less easily under ultra-low pressure and high temperature. be able to.

(1) Thermosetting binder system As the thermosetting binder system, a combination of a compound having two or more thermosetting functional groups in one molecule and a curing agent is usually used, and a catalyst capable of further promoting a thermosetting reaction. May be added. An epoxy group is preferably used as the thermosetting functional group. Further, these may further contain a polymer which is not polymerized by itself.

  As a compound having two or more thermosetting functional groups in one molecule, from the viewpoint of film ejection properties of ink jet and film physical properties such as solvent resistance, adhesion and ITO resistance of pixels formed by the ink jet ink, 1 Epoxy compounds having two or more epoxy groups in the molecule are preferably used. An epoxy compound having two or more epoxy groups in one molecule is an epoxy compound having two or more, preferably 2 to 50, more preferably 2 to 20 epoxy groups in one molecule (referred to as an epoxy resin). Is included). The epoxy group should just be a structure which has an oxirane ring structure, for example, can show a glycidyl group, an oxyethylene group, an epoxycyclohexyl group, etc. Examples of the epoxy compound include known polyvalent epoxy compounds that can be cured by carboxylic acid. Examples of such an epoxy compound include “Epoxy resin handbook” edited by Masaki Shinbo, published by Nikkan Kogyo Shimbun (Showa 62). These can be used widely.

  As an epoxy compound, in order to impart solvent resistance and heat resistance to the cured film, to increase the crosslink density of the polymer with a relatively high molecular weight and the cured film, or to improve the inkjet ejection performance by lowering the viscosity In addition, it is preferable to use a compound having a relatively low molecular weight in combination.

i) Compound having two or more thermosetting functional groups in one molecule As an epoxy compound (hereinafter sometimes referred to as “binder epoxy compound”) which is a polymer having a relatively high molecular weight, which is usually used as a binder component. May be a polymer composed of at least a structural unit represented by the following formula (A) and a structural unit represented by the following formula (B) and having two or more glycidyl groups.

(R ¹¹ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ¹² is a hydrocarbon group having 1 to 12 carbon atoms.)

(R ¹³ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.)
The structural unit represented by the formula (A) is derived from a monomer represented by the following formula (C).

(R ¹¹ and R ¹² are the same as in formula (A).)

By using the monomer represented by the formula (C) as a constituent unit of the binder epoxy compound, sufficient hardness and transparency can be imparted to the cured coating film formed from the inkjet ink of the present invention. In the formula (C), R ¹² is a hydrocarbon group having 1 to 12 carbon atoms, which may be a linear aliphatic, alicyclic or aromatic hydrocarbon group, and further has an additional structure, For example, it may contain a double bond, a side chain of a hydrocarbon group, a side chain of a spiro ring, an intra-ring bridged hydrocarbon group, or the like.

  Specific examples of the monomer represented by the formula (C) include methyl (meth) acrylate, ethyl (meth) acrylate, i-propyl (meth) acrylate, n-propyl (meth) acrylate, and i-butyl (meth). Acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) acrylate, Examples thereof include para-t-butylcyclohexyl (meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate, dicyclopentenyl (meth) acrylate, and phenyl (meth) acrylate.

In the formula (C), hydrogen or a methyl group is preferable as R ¹¹ , and an alkyl group having 1 to 12 carbon atoms is preferable as R ¹² , among which a methyl group and a cyclohexyl group are particularly preferable. Preferable examples of the monomer represented by the above formula (C) include methyl methacrylate (MMA) and cyclohexyl methacrylate (CHMA).
The structural unit represented by the formula (B) in the polymer is derived from a monomer represented by the following formula (D).

(R ¹³ is the same as in formula (B).)

  The monomer represented by the formula (D) is used for introducing an epoxy group (epoxy reaction point) into the polymer. The ink-jet ink containing the polymer is excellent in storage stability, and does not easily increase in viscosity during storage and discharge operations. One of the reasons is the epoxy group in formula (B) or formula (D). Is presumed to be because of glycidyl group. When an alicyclic epoxy acrylate is used instead of the monomer represented by the formula (D), the viscosity of the inkjet ink is likely to increase.

In formula (D), R ¹³ is preferably hydrogen or a methyl group. Specific examples of the monomer represented by the formula (D) include glycidyl (meth) acrylate, and glycidyl methacrylate (GMA) is particularly preferable.

  The polymer may be a random copolymer or a block copolymer. Further, the polymer may contain a main chain constituent unit other than the formula (A) or the formula (B) as long as the performance required for each detail of the color filter, such as hardness and transparency, can be ensured. Good. Specific examples of such a monomer include acrylonitrile and styrene.

  The content of the structural unit of the formula (A) and the structural unit of the formula (B) in the binder epoxy compound is derived from the monomer that derives the structural unit of the formula (A) and the structural unit of the formula (B). The weight ratio with the monomer to be charged (monomer that induces formula (A): monomer that induces formula (B)) is in the range of 10:90 to 90:10. preferable.

  When the amount of the structural unit of the formula (A) is more than the above ratio of 10:90, there is a possibility that the reaction point of curing is decreased and the crosslinking density is lowered, whereas the structural unit of the formula (B) If the amount is more than the above ratio 90:10, the bulky skeleton may be reduced and curing shrinkage may be increased.

  The weight average molecular weight of the binder epoxy compound is preferably 3,000 or more, particularly 4,000 or more, when expressed in terms of polystyrene-converted weight average molecular weight. This is because if the molecular weight of the binder epoxy compound is less than 3,000, 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. On the other hand, the weight average molecular weight of the binder epoxy compound is preferably 20,000 or less, more preferably 15,000 or less, when expressed in terms of polystyrene-converted weight average molecular weight. If the molecular weight is more than 20,000, the viscosity is likely to increase, and the stability of the ejection amount and the straightness of the ejection direction when ejecting from the ejection head by the inkjet method may be deteriorated, and the stability of long-term storage It is because there is a possibility that it may become worse.

  As the binder epoxy compound, a polystyrene-reduced weight average molecular weight (Mw) is in the above range, and a GMA / MMA copolymer polymerized using at least glycidyl methacrylate (GMA) and methyl methacrylate (MMA) is used. Is particularly preferred. The GMA / MMA copolymer may be polymerized by containing other monomer components as long as the object of the present invention can be achieved.

  As an example of the synthesis of the binder epoxy compound, for example, a four-necked flask equipped with a thermometer, reflux condenser, stirrer, and dropping funnel is charged with a solvent that does not contain a hydroxyl group, and the temperature is raised to 140 ° C. while stirring. . The reason for using a solvent that does not contain a hydroxyl group is to avoid the decomposition of the epoxy group during the synthesis reaction. Next, a mixture of the monomer represented by the above formula (C), the monomer represented by the above formula (D), and a composition obtained by combining other monomers as necessary with a polymerization initiator (dropping component) is 2 Drop at a constant rate from the dropping funnel over time. After completion of the dropping, the temperature is lowered to 110 ° C., a catalyst is added, the reaction is performed for 3 hours, and the reaction is terminated when the temperature is raised to 130 ° C. and maintained for 2 hours, whereby the binder epoxy compound is obtained.

  The thermosetting binder system used in the present invention is an epoxy compound having two or more epoxy groups in one molecule (hereinafter, sometimes referred to as “polyfunctional epoxy compound”), which is based on the binder epoxy compound. Alternatively, those having a small molecular weight may be used. Especially, it is preferable to use the said binder epoxy compound and the said polyfunctional epoxy compound together as mentioned above. In this case, the polystyrene equivalent weight average molecular weight of the polyfunctional epoxy compound is preferably 4,000 or less, and particularly preferably 3,000 or less, on condition that it is smaller than the binder epoxy compound combined therewith.

  Since the epoxy group (glycidyl group) is introduced into the binder epoxy compound by the structural unit represented by the formula (B), the amount of epoxy that can be introduced into the molecule of the copolymer is limited. When a polyfunctional epoxy compound having a relatively small molecular weight is added to the ink-jet ink, the epoxy group is replenished in the ink-jet ink, the reaction point concentration of the epoxy is increased, and the crosslinking density can be increased.

  Among polyfunctional epoxy compounds, it is preferable to use an epoxy compound having four or more epoxy groups in one molecule in order to increase the crosslink density of the acid-epoxy reaction. In particular, when the weight average molecular weight of the binder epoxy compound is set to 10,000 or less in order to improve the discharge performance from the inkjet discharge head, the strength and hardness of the cured layer are likely to decrease. It is preferable to add a tetrafunctional or higher polyfunctional epoxy compound to the inkjet ink to sufficiently increase the crosslinking density.

  The polyfunctional epoxy compound 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 novolak 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 included Polyol type epoxy resins, polypropylene glycol type epoxy resin, a glycidyl ester 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 jER828 (made by Japan Epoxy Resin Co., Ltd.), bisphenol F type epoxy resin such as trade name YDF-175S (made by Toto Kasei Co., Ltd.), trade name YDB-715 (Toto) Brominated bisphenol A type epoxy resin such as Kasei Co., Ltd., bisphenol S type epoxy resin such as EPICLON EXA1514 (Dainippon Ink Chemical Co., Ltd.), and hydroquinone type such as YDC-1312 (made by Tohto Kasei Co., Ltd.) Epoxy resin, biphenyl type epoxy resin such as naphthalene type epoxy resin such as trade name EPICLON EXA4032 (manufactured by Dainippon Ink and Chemicals), bisphenol A type novolac epoxy resin such as jER157S70 (made by Japan Epoxy Resin), product Phenol novolac type epoxy resin such as name jER154 (manufactured by Japan Epoxy Resin Co., Ltd.), Cresol novolac type epoxy resin such as product name YDCN-701 (manufactured by Tohto Kasei Co., Ltd.), trade name EPICLON HP-7200 (manufactured by Dainippon Ink & Chemicals, Inc.) Dicyclopentadiene phenol type epoxy resin such as), trishydroxyphenylmethane type epoxy resin such as trade name jER1032H60 (manufactured by Japan Epoxy Resin), trifunctional epoxy resin such as trade name VG3101M80 (manufactured by Mitsui Chemicals), trade name Tetraphenylol ethane type epoxy resin such as jER1031S (manufactured by Japan Epoxy Resin Co., Ltd.), tetrafunctional type epoxy resin such as trade name Denacol EX-411 (manufactured by Nagase Kasei Kogyo Co., Ltd.), trade name ST-3000 (Toto Kasei Co., Ltd.) ) Hydrogenated bisphenol A type epoxy resin, trade name jER190P (made by Japan Epoxy Resin Co.), glycidyl ester type epoxy resin, trade name YH-434 (made by Tohto Kasei Co., Ltd.), glycidyl amine type epoxy resin, trade name Glyoxal type epoxy resin such as YDG-414 (manufactured by Tohto Kasei Co., Ltd.), alicyclic polyfunctional epoxy compound such as trade name Epolide GT-401 (manufactured by Daicel Chemical Industries), and heterocyclic epoxy such as triglycidyl isocyanate (TGIC) Resin etc. can be illustrated. Further, if necessary, a trade name Neotote E (manufactured by Toto Kasei Co., Ltd.) can be mixed as an epoxy reactive diluent.

  Among these polyfunctional epoxy compounds, bisphenol A type novolac epoxy resins such as trade name jER157S70 (made by Japan Epoxy Resin Co., Ltd.) and cresol novolac type epoxy resins such as trade name YDCN-701 (made by Toto Kasei Co., Ltd.) are used. Particularly preferred.

<Blending ratio of epoxy compound>
The blending ratio of the binder epoxy compound and the polyfunctional epoxy compound blended as necessary is 10 to 80 parts by weight of the binder epoxy compound and 10 to 60 parts by weight of the polyfunctional epoxy compound in weight ratio. It is preferable to mix, and it is more preferable to mix 20-60 parts by weight of the binder epoxy compound and 20-50 parts by weight of the polyfunctional epoxy compound, and 30-40 parts by weight of the binder epoxy compound is multifunctional. It is particularly preferable to blend the epoxy compound in a proportion of 25 to 35 parts by weight.

ii) Curing Agent The thermosetting binder system used in the present invention is usually combined with a curing agent. As the curing agent, for example, a polyvalent carboxylic acid anhydride or a polyvalent carboxylic acid is used.
Specific examples of the polyvalent carboxylic acid anhydride include phthalic anhydride, itaconic anhydride, succinic anhydride, citraconic anhydride, dodecenyl succinic anhydride, tricarballylic anhydride, maleic anhydride, hexahydrophthalic anhydride, dimethyltetrahydro anhydride Aliphatic or alicyclic dicarboxylic anhydrides such as phthalic acid, hymic anhydride, and nadic anhydride; fats such as 1,2,3,4-butanetetracarboxylic dianhydride and cyclopentanetetracarboxylic dianhydride Aromatic polycarboxylic dianhydrides; aromatic polycarboxylic anhydrides such as pyromellitic anhydride, trimellitic anhydride, and benzophenone tetracarboxylic anhydride; ester groups such as ethylene glycol bistrimellitate and glycerin tristrimitate Containing acid anhydrides, particularly preferably aromatic poly It may be mentioned carboxylic acid anhydrides. Moreover, the epoxy resin hardening | curing agent which consists of a commercially available carboxylic acid anhydride can also be used suitably.

  Specific examples of the polyvalent carboxylic acid used in the present invention include aliphatic polyvalent carboxylic acids such as succinic acid, glutaric acid, adipic acid, butanetetracarboxylic acid, maleic acid, and itaconic acid; hexahydrophthalic acid, Aliphatic polycarboxylic acids such as 1,2-cyclohexanedicarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, cyclopentanetetracarboxylic acid, and phthalic acid, isophthalic acid, terephthalic acid, pyromellitic acid, trimellitic acid, Aromatic polyvalent carboxylic acids such as 1,4,5,8-naphthalenetetracarboxylic acid and benzophenonetetracarboxylic acid can be mentioned, and aromatic polyvalent carboxylic acids can be mentioned preferably.

  These curing agents can be used singly or in combination of two or more. The compounding amount of the curing agent used in the present invention is an epoxy group-containing component (a binder epoxy compound and a polyfunctional epoxy compound, and an epoxy resin represented by the specific formula (1) used as the dispersion auxiliary resin). The amount is usually in the range of 1 to 100 parts by weight, preferably 5 to 50 parts by weight per 100 parts by weight. If the blending amount of the curing agent is less than 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 exceeds 100 weight part, there exists a possibility that the adhesiveness with respect to the board | substrate of a coating film may be inferior.

iii) Catalyst In order to improve the hardness and heat resistance of the cured layer, a catalyst capable of promoting an acid-epoxy thermosetting reaction may be added to the thermosetting binder system used in the present invention. As such a catalyst, a thermal latent catalyst that exhibits activity during heat curing can be used.
The heat-latent catalyst exhibits catalytic activity when heated, accelerates the curing reaction and gives good properties to the cured product, and is added as necessary. The thermal latent catalyst is preferably one that exhibits acid catalytic activity at a temperature of 60 ° C. or higher. As such, a compound obtained by neutralizing a protonic acid with a Lewis base, a compound obtained by neutralizing a Lewis acid with a Lewis base, Lewis Examples thereof include a mixture of an acid and a trialkyl phosphate, sulfonic acid esters, onium compounds and the like, and various compounds described in JP-A-4-218561 can be used. Specifically, (i) compounds obtained by neutralizing halogenocarboxylic acids, sulfonic acids, phosphoric acid mono- and diesters with various amines such as ammonia, monomethylamine, triethylamine, pyridine, ethanolamine, or trialkylphosphine (B) compounds obtained by neutralizing Lewis acids such as BF ₃ , FeCl ₃ , SnCl ₄ , AlCl ₃ , ZnCl ₂ with the aforementioned Lewis base, (c) methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid, etc. Examples include primary alcohols, ester compounds with secondary alcohols, (d) primary alcohols, secondary monoalcohol phosphate monoester compounds, and phosphate diester compounds. Examples of the onium compound include an ammonium compound [R ₃ NR ′] ⁺ X ⁻ , a sulfonium compound [R ₃ SR ′] ⁺ X ⁻ , and an oxonium compound [R ₃ OR ′] ⁺ X ⁻ . Here, R and R ′ are alkyl, alkenyl, aryl, alkoxy and the like.
The thermal latent catalyst is usually blended at a ratio of about 0.01 to 10.0 parts by weight with respect to a total of 100 parts by weight of the compound having two or more thermosetting functional groups in one molecule and the curing agent. .

(2) Photo-curable binder system i) Polymer In a binder system containing a photo-curable resin that can be polymerized and cured by light such as ultraviolet rays and electron beams, it provides film formability and adhesion to the coated surface. For this purpose, it is preferable to include a polymer having a relatively high molecular weight. Here, the relatively high molecular weight means that the molecular weight is higher than that of so-called monomers and oligomers, and the weight average molecular weight can be 5,000 or more. As a polymer having a relatively high molecular weight, any of a polymer having no polymerization reactivity per se and a polymer having a polymerization reactivity per se may be used, and a combination of two or more types may be used. May be. It is mainly composed of a polymer having a relatively high molecular weight, and if necessary, a polyfunctional monomer or oligomer, a monofunctional monomer or oligomer, a photopolymerization initiator activated by light, and a sensitizer. Thus, a photocurable binder system is constituted.

  When a polymer having no polymerization reactivity is used as a polymer having a relatively high molecular weight, a polyfunctional monomer such as a bifunctional or higher polyfunctional monomer or oligomer is blended in the binder system. In this case, in the binder system, the polyfunctional polymerizable component itself spontaneously polymerizes by light irradiation, or polymerizes by the action of other components such as a photopolymerization initiator activated by light irradiation. A network structure is formed in the coating film, and components such as resins and pigments having no polymerization reactivity are encapsulated in the network structure and cured.

As such a polymer having no polymerization reactivity, for example, a copolymer composed of two or more of the following monomers can be used: (meth) acrylic acid (hereinafter, this expression is expressed by acrylic acid and methacrylic acid). Both are collectively referred to)), methyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, benzyl (meth) acrylate, styrene, polystyrene macromonomer, and polymethylmethacrylate macromonomer.
More specifically, methacrylic acid / benzyl methacrylate copolymer, methacrylic acid / benzyl methacrylate / styrene copolymer, benzyl methacrylate / styrene copolymer, benzyl methacrylate macromonomer / styrene copolymer, benzyl methacrylate / styrene macromonomer A copolymer etc. can be illustrated.

As a polymer having a polymerization reactivity per se, it is an oligomer obtained by introducing a polymerizable functional group into a polymer molecule having no polymerization reactivity or a polymer having a higher molecular weight than an oligomer, and is subjected to light irradiation. Those that cause a polymerization reaction themselves or that induce a polymerization reaction by the action of other components such as a photopolymerization initiator activated by irradiation with light can be used.
Various ethylenic double bond-containing compounds themselves have polymerization reactivity and can be used as photocurable resins. Conventionally, prepolymers blended in UV inkjet inks used in various fields such as inks, paints and adhesives can be used as a polymer having a relatively high molecular weight in the present invention. Conventionally known prepolymers include radical polymerization type prepolymers, cationic polymerization type prepolymers, thiol / ene addition type prepolymers, and any of them may be used.

  Among these, radical polymerization type prepolymers are most easily available on the market, such as ester acrylates, ether acrylates, urethane acrylates, epoxy acrylates, amino resin acrylates, acrylic resin acrylates, unsaturated polyesters. Examples can be given.

Especially, the following graft polymers are mentioned as a comparatively high molecular weight polymer which can be used suitably in this invention.
The graft polymer suitably used in the present invention has a weight average molecular weight of 5,000 or more, and one of the main chain and the graft portion is composed of a styrenic polymer chain containing a styrenic monomer unit, and the other Is a graft polymer composed of methacrylate polymer chains containing methacrylate monomer units.

  The graft polymer may have a structure in which a main chain (trunk) is constituted by a styrene polymer chain and a graft part is constituted by a methacrylate polymer chain, and conversely, the main chain is constituted by a methacrylate polymer chain. And a structure in which a graft portion is constituted by a styrenic polymer chain. Among the above, those having a structure in which a main chain is constituted by a styrene polymer chain and a graft part is constituted by a methacrylate polymer chain are preferred.

  The styrenic polymer chain is a polymer chain mainly composed of a styrenic monomer, and may be a homopolymer of only one kind of styrenic monomer or a copolymer of two or more kinds of styrenic monomers. It may be a copolymer of a styrene monomer and another monomer.

In addition to styrene, the styrenic monomer includes styrene monomers with substituents such as alkyl-substituted styrene (methyl styrene, ethyl styrene, trimethyl styrene, octyl styrene, etc.), methoxy styrene, and α-methyl styrene.
Examples of the monomer that can be copolymerized with the styrene monomer include various (meth) acrylate monomers, acrylonitrile, amide monomers, and the like.

In the inkjet ink used in the present invention, from the viewpoint of pigment dispersibility, the styrenic polymer chain preferably contains styrene monomer units in a proportion of 50% by weight or more, and more preferably in a proportion of 60% by weight or more. Is particularly preferred.
The methacrylate polymer chain is a polymer chain mainly composed of methacrylate and may be a homopolymer of only one type of methacrylate or a copolymer of two or more types of methacrylate, or methacrylate. And a copolymer of other monomers.

  As methacrylate monomers, alkyl methacrylates (methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, hexyl methacrylate, octyl methacrylate, lauryl methacrylate, etc.), benzyl methacrylate, phenoxyethyl methacrylate, tetrahydrophthalimide Examples include ethyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, tetrahydrofurfuryl methacrylate, methoxypolyethylene glycol methacrylate, and butoxyethyl methacrylate. It is preferable to select and use a methacrylate monomer so that a graft polymer having a Tg of 30 ° C. or higher can be obtained. A graft polymer having a Tg of less than 30 ° C. is not preferable because the film hardness after curing decreases.

Moreover, as a monomer to be copolymerized with methacrylate, alkyl acrylate, hydroxyalkyl acrylate, amide monomer, imide group-containing monomer, alkylene glycol (meth) acrylate, Daicel Chemical's brand name Plexel FM series, or the like can be used.
The methacrylate polymer has a relatively high Tg and is excellent in hardness and dispersibility because it causes microphase separation from styrene. From this point of view, the methacrylate polymer chain preferably contains a methacrylate monomer unit in a proportion of 50% by weight or more, more preferably 70% by weight or more.

  The graft polymer may have a photopolymerizable functional group such as an ethylenically unsaturated bond or an epoxy group. Photocurability can be imparted by introducing a photopolymerizable functional group into the graft polymer. The graft polymer into which the photopolymerizable functional group has been introduced can be suitably used as a photocurable resin having a relatively high molecular weight in the present invention since the crosslinking point is improved and the surface hardness is improved. When the polymerizable functional group of the graft polymer is an ethylenically unsaturated bond, it can be cured by a photoradical polymerization reaction, and when the polymerizable functional group is an epoxy group, photocationic polymerization is possible. . In particular, a graft polymer having an ethylenically unsaturated bond is used in combination with an ethylenically unsaturated bond-containing monomer such as a (meth) acrylic monomer and / or an oligomer to obtain an inkjet ink having excellent curing reactivity. Can do. The photopolymerizable functional group may be introduced into one or both of the styrenic polymer chain or the methacrylate polymer chain, or may be introduced into one or both of the main chain and the graft portion.

  Among them, the graft polymer has an ethylenically unsaturated bond in an ethylenically unsaturated bond equivalent of 1200 g / eq or less, and one of the main chain and the graft portion contains a styrene monomer unit. A preferred graft polymer is a graft polymer composed of a styrene methacrylate polymer chain and the other composed of a benzyl methacrylate polymer chain containing a monomer unit derived from benzyl methacrylate. Among the methacrylate monomers, benzyl methacrylate is particularly excellent in pigment dispersibility, and is therefore preferably used for an ink-jet ink for a color filter for forming pixels and the like.

The graft polymer may have a structure in which a main chain (trunk) is constituted by a styrene polymer chain and a graft part is constituted by a benzyl methacrylate polymer chain, and conversely, by a benzyl methacrylate polymer chain. It may have a structure in which the main chain is constituted and the graft portion is constituted by a styrene polymer chain. Among the above, those having a structure in which a main chain is constituted by a styrene polymer chain and a graft part is constituted by a benzyl methacrylate polymer chain are preferred.
The benzyl methacrylate polymer chain of the graft polymer is a polymer chain mainly composed of benzyl methacrylate, and may be a homopolymer of benzyl methacrylate, or a copolymer of benzyl methacrylate and other monomers as described above. It may be a coalescence.
The benzyl methacrylate-based polymer chain preferably contains benzyl methacrylate monomer units in a proportion of 30% by weight or more, particularly preferably 50% by weight or more.

  The graft polymer has at least one of the main chain or graft portion having an ethylenically unsaturated bond, and can be cured by light or thermal radical polymerization reaction. The ethylenically unsaturated bond equivalent of the graft polymer needs to be 1200 g / eq or less, and preferably 700 g / eq or less. Here, the ethylenically unsaturated bond equivalent is a value obtained by dividing the weight average molecular weight of the graft polymer by the number of ethylenically unsaturated bonds contained in one molecule. This is because when the ethylenically unsaturated bond equivalent of the graft polymer exceeds 1200 g / eq, the film hardness after curing and the solvent resistance may be insufficient. On the other hand, a graft polymer having an ethylenically unsaturated bond equivalent of 1200 g / eq or less is excellent in various physical properties such as solvent resistance, hardness, strength, and adhesion because there are many ethylenically unsaturated bonds contained in one molecule. is there. Even in the case where a graft polymer having a relatively low molecular weight is used in order to improve the ejection property, it can be sufficiently cured if the ethylenically unsaturated bond equivalent is 1200 g / eq or less, so that the ink has excellent ejection properties. This is because a cured film having excellent physical properties can be formed.

The weight ratio of the graft (branch) portion / main chain (trunk) portion of the graft polymer is preferably 20/80 to 80/20, and more preferably 30/70 to 70/30. If the weight ratio of the graft portion is less than 20%, the solubility, viscosity, fluidity, dischargeability and the like are deteriorated. On the other hand, when the weight ratio of the main chain portion is less than 20%, the pigment dispersibility is deteriorated.
Furthermore, by changing the acid value and amine value of the above graft polymer, various physical properties such as ink solvent solubility, film solvent resistance, pigment dispersion stability, dyeability, film hardness, and film strength can be adjusted. it can.

  The method for producing the graft polymer includes (1) a method in which a monomer is polymerized under a peroxide catalyst and grafted by hydrogen abstraction, and (2) a polymer having a functional group at one end and other functional groups. Although a method of adding the attached polymer and (3) a method of copolymerizing a polymerizable polymer (macromonomer) and a monomer can be used, the macromonomer method is preferred because the purity of the product is high. As a procedure for synthesizing the graft polymer, reference can be made to specific examples of paragraph numbers 0094 to 0105 of JP-A-2002-201387.

In addition, since the ink used in the present invention is an ink used in an ink jet system, the molecular weight of a polymer having a relatively high molecular weight is set so that the viscosity of the ink is not too high to adversely affect the discharge performance from the discharge head. The weight average molecular weight is preferably 25,000 or less.
The polymer having a relatively high molecular weight is preferably blended at a ratio of 1 to 50% by weight with respect to the total solid content of the inkjet ink.

ii) Polyfunctional polymerizable component In order to improve the strength of the coating film and the adhesion to the substrate even in the case of using a polymer having a relatively high molecular weight that can be polymerized and cured, a polyfunctional monomer It is preferable to blend a polyfunctional polymerizable component such as olefin or oligomer. Polymer molecules with relatively high molecular weight that are polymerizable not only polymerize with polymers with relatively high molecular weight, but also polymerize with other polymerizable components such as polyfunctional monomers to form a network and cure. To do.
As the polyfunctional polymerizable component forming the network structure of the coating film, a bifunctional or higher functional monomer or oligomer can be used. In order to impart sufficient film strength and adhesion to the photocurable resin, a tetrafunctional or higher functional monomer or oligomer is usually used.

  However, in particular, since the ink used in the present invention is used as an ink jet ink, the polymerizable component other than the polymer having a relatively high molecular weight is a bifunctional to trifunctional monomer or oligomer or monomer having a relatively small number of functional groups. Is preferably used as a main component, and it is particularly preferable to use a bi- or trifunctional monomer having a viscosity of 100 cps or less. During ink jet spraying, it is difficult for the viscosity to increase at the tip of the head, clogging of the head does not occur, and ink ejection during operation is stable, so the amount and direction of ink ejection is stable. This is because the ink can be accurately and uniformly deposited on the substrate in a predetermined pattern.

  Examples of the bifunctional to trifunctional monomers include 1,6-hexanediol diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, and polyethylene glycol diester. Examples thereof include acrylate, polypropylene glycol diacrylate, trimethylolpropane triacrylate, and 3-butylene glycol dimethacrylate.

In the ink-jet ink used in the present invention, the blending ratio of the bi- to tri-functional monomer is preferably 20 to 70% by weight with respect to the total solid content of the ink-jet ink.
If the blending ratio of the bi- or trifunctional monomer is less than 20% by weight of the total solid content, the ink-jet ink is not sufficiently diluted with the monomer, and the viscosity of the ink is high from the beginning or becomes high after volatilization of the solvent. There is a risk of clogging the nozzles of the inkjet head. In addition, when the blending ratio of the bi- or trifunctional monomer exceeds 70% by weight of the total solid content, the cross-linking density of the coating film becomes low, and the solvent resistance, adhesion, and hardness of the coating film are inferior and sufficient. This is because the characteristics may not be obtained.

However, when all the polyfunctional monomers blended in the ink-jet ink are di- or tri-functional monomers, the viscosity increase due to drying of the ink is unlikely to occur, so that the ejection performance of the ink-jet head is stable. The cured layer obtained by curing the ink layer may have insufficient film strength, adhesion to the substrate, solvent resistance, and the like. Therefore, by adding an appropriate amount of a tetrafunctional or higher polyfunctional monomer or oligomer together with the above bifunctional to trifunctional monomers, the crosslinking density can be increased, and sufficient film strength and adhesion can be imparted to the pattern of the cured layer. .
Examples of tetrafunctional or higher polyfunctional monomers and oligomers include pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, and the like.

The polyfunctional component having 4 or more functional groups is usually preferably blended at a ratio of 1 to 30% by weight with respect to the total solid content of the inkjet ink. The ink jet ink according to the present invention is 100 parts by weight of 2 to 3 functional monomers in order to balance discharge stability with 2 to 3 functional monomers and strength and adhesion improvement with 4 or more functional components. On the other hand, the blending ratio of the tetrafunctional or higher polyfunctional component is usually 1 to 50 parts by weight, desirably the lower limit of the blending ratio is 2 parts by weight or more, and / or the upper limit of the blending ratio is 35. It is preferable to be not more than parts by weight.
When the blending ratio of the tetrafunctional or higher polyfunctional component is less than 1 part by weight with respect to 100 parts by weight of the bi- to tri-functional monomer, characteristics such as hardness and solvent resistance after the ink is cured May not be sufficiently obtained. Moreover, when the said mixture ratio of the polyfunctional component more than tetrafunctional exceeds 50 weight part, there exists a possibility that the cure rate of an ink may become slow and process speed may become slow.

iii) Monofunctional polymerizable component In addition, the photocurable binder system may contain a monofunctional monomer or oligomer, if necessary.
Examples of monofunctional monomers and oligomers include vinyl monomers such as styrene and vinyl acetate, and monofunctional acrylic monomers such as n-hexyl acrylate and phenoxyethyl acrylate.

iv) Photopolymerization initiator The photocurable binder system is usually blended with a photopolymerization initiator having activity with respect to the wavelength of the light source used. The photopolymerization initiator is appropriately selected in consideration of the difference in the reaction format of the resin or polyfunctional monomer (for example, radical polymerization or cationic polymerization) and the type of each material. For example, 1-hydroxycyclohexyl-phenyl ketone 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-monforinopropan-1-one, 2-benzyl-2- Dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1- [4- (2-hydroxyethoxy) phenyl] 2-hydroxy-2-methyl-1-propan-1-one, 2,4,6-trimethylbenzoyldiphenyl-phosphine oxide, bisacyl phosphite Oxide, benzoin ethyl ether, benzoin isobutyl ether, benzoin isopropyl ether, 2-isopropylthioxanthone, 2,4-diethylthioxanthone, 2- (3-dimethylamino-2-hydroxypropoxy) -3,4-dimethyl-9H-thioxanthone- 9-one mesochloride, benzophenone, methyl o-benzoylbenzoate, 4-benzoyl-4′-methyl-diphenyl sulfide, 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl), p-dimethyl Aminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid isoamyl ester, 1,3,5-triacroylhexahydro-s-triazine, 2- [2- (5-methylfuran-2-yl) ethenyl] -4 , 6-Bis (trichloromethyl) ) -S-triazine, 2- [2- (furan-2-yl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine, methylbenzoylformate, 2,4,6-trimethylbenzoyldiphenylphos A photopolymerization initiator such as fin oxide can be used.

In addition, it is preferable that content of a photoinitiator is 0.1 to 5 weight% with respect to the whole solid, and also 0.5 to 2 weight% with respect to the whole solid.
Further, in order to impart sufficient adhesion, strength and hardness to the cured ink layer, the total proportion of binder components in the total solid content of the ink including pigments and other components is 25% by weight or more. Is preferred.

(Other ingredients)
One or more other additives can be blended in the ink-jet ink for color filter of the present invention, if necessary. The following can be illustrated as such an additive.
a) Sensitizer: For example, 4-diethylaminoacetophenone, 4-dimethylaminopropiophenone, ethyl-4-dimethylaminobenzoate, 2-ethylhexyl-1,4-dimethylaminobenzoate and the like.
b) Curing accelerator (chain transfer agent): For example, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2,5-dimercapto-1,3,4-thiadiazole, etc.
c) Photocrosslinking agent or photosensitizer comprising a polymer compound: The polymer photocrosslinking / sensitizing agent has a functional group capable of functioning as a photocrosslinking agent or photosensitizer in the main chain and / or side chain. Examples of the polymer compound include a condensate of 4-azidobenzaldehyde and polyvinyl alcohol, a condensate of 4-azidobenzaldehyde and a phenol novolac resin, and a (co-copolymer of 4- (meth) acryloylphenyl cinnamoyl ester. ) Polymer, 1,4-polybutadiene, 1,2-polybutadiene and the like.
d) Filler: For example, glass, alumina and the like.
e) Adhesion promoter: for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane.
f) Antioxidant: For example, 2,2-thiobis (4-methyl-6-t-butylphenol), 2,6-di-t-butylphenol and the like.
g) Ultraviolet absorber: For example, 2- (3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, alkoxybenzophenone and the like.

(Combination ratio of each component in ink)
The pigment is usually blended in a proportion of 1 to 60% by weight, preferably 15 to 40% by weight, based on the total solid content of the inkjet ink. If the amount of the pigment is too small, the transmission density when the ink-jet ink is applied to a predetermined film thickness (usually 0.5 to 2.5 μm) may not be sufficient. Moreover, when there are too many pigments, the characteristics as a coating film such as adhesion to the substrate when the ink-jet ink is applied and cured on the substrate, surface roughness of the cured film, and coating film hardness may be insufficient. There is.
The content of the pigment dispersant is preferably 5 to 100 parts by weight, more preferably 100 parts by weight with respect to 100 parts by weight of the pigment from the viewpoint of pigment dispersibility and pigment dispersion stability over time, as in the case of the pigment dispersion. 10 to 80 parts by weight.

The content of the dispersion auxiliary resin is 5 to 80 parts by weight with respect to 100 parts by weight of the pigment dispersant from the viewpoint of pigment dispersibility and the heat resistance of the cured film after ink preparation, as in the case of the pigment dispersion. The amount is preferably 10 to 60 parts by weight. Moreover, it is preferable that content of dispersion | distribution auxiliary resin is 5-70 weight part with respect to 100 weight part of said binder systems.
The binder system is usually blended at a ratio of 20 to 80% by weight with respect to the total solid content of the inkjet ink.

Moreover, in the inkjet ink which concerns on this invention, it is preferable that the mixture weight ratio (P / V) of the said pigment (P) with respect to solid content (V) other than a pigment is 0.1-1.2.
Among these, the pigment includes at least one pigment selected from the group consisting of CI Pigment Red 254 (PR254), CI Pigment Red 177 (PR177), and CI Pigment Yellow 150 (PY150). In some cases, the blending weight ratio (P / V) of the pigment (P) to the solid content (V) other than the pigment is preferably 0.1 to 1.2.
The pigment may be one or more pigments selected from the group consisting of CI Pigment Green 36 (PG36), CI Pigment Green 7 (PG7), CI Pigment Yellow 150 (PY150), and CI Pigment Yellow 138 (PY138). When the green ink is used, it is preferable that the blending weight ratio (P / V) of the pigment (P) to the solid content (V) other than the pigment is 0.5 to 1.2. .
Furthermore, CI pigment blue 15: 6 (PB15: 6) and / or CI pigment violet 23 (PV23) is included as the pigment, and when it is a blue ink, The blending weight ratio (P / V) of the pigment (P) is preferably 0.1 to 0.6.

  In the inkjet ink according to the present invention, the solvent has a main solvent ratio of 60% by weight or more of the total amount of the solvent. In this case, when the inkjet ink described later is used, drying properties and evaporation properties suitable for the inkjet method can be obtained, and the intermittent ejection stability of the inkjet is improved. From the viewpoints of pigment dispersibility, pigment dispersion stability over time, and ink wetting and spreading, the ratio of the main solvent is 70 to 95% by weight of the total amount of the solvent, 75 to 95% by weight of the total amount of the solvent, and even more of the total amount of the solvent. It is preferable to set it as 80 to 92 weight%. The proportion of the sub-solvent is preferably 5 to 30% by weight of the total amount of the solvent, 5 to 25% by weight of the total amount of the solvent, and further 8 to 20% by weight of the total amount of the solvent.

  Such a solvent is usually used in an amount of 40 to 95% by weight, and further 70 to 95% by weight, based on the total amount of the ink containing the solvent, to prepare ink to be ejected. If the amount of the solvent is too small, the viscosity of the ink is high and it becomes difficult to discharge from the inkjet head. Also, if there is too much solvent, the ink film deposited on the wettability change site will be broken before the ink deposit (ink deposition amount) for the predetermined wettability change site (ink layer formation site) is not sufficient. , It protrudes to the surroundings, and further spreads to the adjacent wettability change site (ink layer formation site). In other words, the amount of ink that can be deposited without sticking out from the wettability change site (ink layer forming site) to which the ink is to be attached becomes insufficient, the film thickness after drying is too thin, The transmission density cannot be obtained.

(Ink production method)
The method for producing an inkjet ink for a color filter according to the present invention includes at least a pigment, a pigment dispersant, and an epoxy resin represented by the following general formula (1) as a main solvent having a boiling point of 180 ° C. to 260 ° C. Mixing with a dispersion preparation solvent containing at least a solvent component having a vapor pressure of 0.5 mmHg or less, and dispersing to prepare a pigment dispersion;

(However, R ¹ is a residue obtained by removing active hydrogen in an organic compound having k active hydrogens. N1, n2,... And k is an integer of 1 to 100. A is an oxynorbornene skeleton having a substituent X or an oxycyclohexane skeleton having a substituent X, and is represented by the following formula:

It has the process of adjusting so that the mixture ratio of the said main solvent to the solvent whole quantity may be 60 weight% or more by the method in any one of following 1) -3.
1) The obtained pigment dispersion and at least the binder system are mixed with the newly prepared main solvent and / or auxiliary solvent.
2) At least a binder system is prepared by dissolving or dispersing in a newly prepared main solvent and / or auxiliary solvent to prepare a binder solution, and then the binder solution and the pigment dispersion are mixed.
3) At least a binder system is prepared by dissolving or dispersing in a newly prepared main solvent and / or auxiliary solvent to prepare a binder solution, and then the binder solution, the pigment dispersion, and the main solvent and / or auxiliary solvent are mixed. .

  In the method for producing the ink of the present invention, when the pigment dispersion is prepared, the specific epoxy resin is used as a dispersion auxiliary resin, so that a pigment dispersion excellent in pigment dispersibility and pigment dispersion stability over time can be obtained. Can do. As a result, it is possible to prepare an ink with improved brightness and contrast when applied to a color filter.

  Further, the binder system and other components as required may be mixed with the newly prepared main solvent and / or sub-solvent as in 1) above, but as in 2) and 3) above. In addition, after preparing a binder solution by dissolving or dispersing in a main solvent and / or sub-solvent newly prepared in advance, a mixture with a previously obtained pigment dispersion is more suitable for pigment dispersibility and pigment dispersion. This is preferable from the viewpoint of maintaining good stability over time. The solvent used for preparing the binder solution may be the main solvent alone, the sub solvent alone, or the mixed solvent of the main solvent and the sub solvent in accordance with the binder to be used.

  Even when the binder solution is prepared in advance, the blending ratio of the main solvent in the total amount of the ink solvent is finally adjusted to be 60% by weight or more. For this reason, if there is a residual solvent, use a solvent that has a composition obtained by subtracting the solvent used in the preparation of the pigment dispersion or binder solution from the final composition of the entire solvent, and dilute to the final concentration. An inkjet ink may be completed. As in the above 3), a main solvent and / or a sub-solvent is further mixed into the mixed solution of the binder solution and the pigment dispersion as necessary.

(Use)
The inkjet ink for a color filter according to the present invention is particularly preferably used for forming a film having a predetermined pattern, such as a pixel or a light shielding portion, in a color filter. As the color filter, any of a color filter used for an image output device such as a liquid crystal display device or a color filter used for an image input device such as a solid-state imaging device can be suitably used.

3. Next, the color filter according to the present invention is a color filter including at least a transparent substrate and a pixel provided on the transparent substrate, and the pixel is an inkjet ink for a color filter according to the present invention. It is characterized by being a cured film.
Since the color filter according to the present invention is formed by curing the ink for a color filter according to the present invention, the pixel is less likely to cause wrinkles or cracks as described above, There is no problem of coating film defects such as cracks in the coating film, deterioration of adhesion, or wrinkles of adjacent layers laminated on the coating film. Since the pattern of the pixel portion rarely undergoes thermal expansion and contraction, the adjacent layer such as the transparent electrode film is distorted to cause wrinkles on the surface and disconnection. Therefore, display defects are reduced in the color filter and the display panel formed using the ink-jet ink according to the present invention.

  FIG. 1 is a longitudinal sectional view showing an example (color filter 101) of a color filter according to the present invention. The color filter 101 includes a color filter substrate formed from a light shielding portion 2 formed in a predetermined pattern on the transparent substrate 1, and pixels formed in a predetermined pattern in an opening portion of the light shielding portion 2 on the color filter substrate. 7 (7R, 7G, 7B) and a protective film 8 formed to cover the pixel. A transparent electrode film 9 for driving liquid crystal is formed on the protective film 8. An alignment film 10 is formed on the innermost surface of the color filter 101, in this case on the transparent electrode.

  The columnar spacer 12 is a shape of a convex spacer, and is formed at predetermined multiple locations (four locations in FIG. 1) on the transparent electrode 9 in accordance with the region (non-display region) where the light shielding portion 2 is formed. Yes. The columnar spacer 12 is formed on the transparent electrode 9, the pixel 7, or the protective film 8. In the color filter 101, columnar spacers are formed in a sea-island shape on the protective film 8 via the transparent electrode film 9, but the protective film 8 and the columnar spacer 12 are integrally formed so as to cover it. A transparent electrode film 9 may be formed. In the case where the color filter does not include a light shielding portion, a columnar spacer can be formed in a region where pixels are not formed.

(Transparent substrate)
The transparent substrate 1 is not particularly limited as long as it is conventionally used for a color filter. For example, it is transparent with no flexibility such as quartz glass, Pyrex (registered trademark) glass, synthetic quartz plate and the like. A transparent material having flexibility such as a rigid material, a transparent resin film, an optical resin plate, or the like can be used. Among them, Corning 7059 glass is a material having a small coefficient of thermal expansion, excellent dimensional stability and workability in high-temperature heat treatment, and is an alkali-free glass containing no alkali component in the active matrix. Suitable for color filters for color liquid crystal display devices. In the present invention, a transparent substrate is usually used, but a reflective substrate or a white colored substrate can also be used. Moreover, you may use the board | substrate which surface-treated for the purpose of alkali elution prevention, gas-barrier provision, and other purposes as needed.

(Shading part)
The light shielding unit 2 is provided so as to surround the pixels 7R, 7G, and 7B and the outside of the pixel formation region in order to improve the contrast of the display image. The said light-shielding part is formed on the base material mentioned later, and has an opening part.
As the light-shielding portion, one in which openings having the same shape are regularly formed at regular intervals is used. Here, the specific size and arrangement mode of the opening are not particularly limited, and can be arbitrarily determined according to the use of the color filter manufactured according to the present invention.
The light-shielding part is not particularly limited as long as it is made of a material having a desired light-shielding property. Usually, a light-shielding part composed of a light-shielding material and a resin, or a metal material is used.

  When the light-shielding part is composed of a light-shielding material and a resin, as the light-shielding material, a material generally used for a resin light-shielding part used for a color filter can be used. Examples of such light shielding materials include light shielding particles such as carbon fine particles, metal oxides, inorganic pigments, and organic pigments.

  Examples of the resin include ethylene-vinyl acetate copolymer, ethylene-vinyl chloride copolymer, ethylene-vinyl copolymer, polystyrene, acrylonitrile-styrene copolymer, ABS resin, polymethacrylic acid resin, ethylene-methacrylic acid. Acid resin, polyvinyl chloride resin, chlorinated vinyl chloride, polyvinyl alcohol, cellulose acetate propionate, cellulose acetate butyrate, nylon 6, nylon 66, nylon 12, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyvinyl acetal, polyether Ether ketone, polyether sulfone, polyphenylene sulfide, polyarylate, polyvinyl butyral, epoxy resin, phenoxy resin, polyimide resin, polyamide Resins, polyamic acid resins, polyetherimide resins, and phenolic resin, urea resin and the like.

  On the other hand, when the light shielding part is made of a metal material, the metal material is not particularly limited as long as it has a desired light shielding property, but a chromium material is generally used.

The light shielding part may contain a liquid repellent material exhibiting liquid repellency. By including such a liquid repellent material, a color filter substrate having a light-shielding portion with excellent liquid repellency can be obtained without performing a liquid repellent step described later.
The liquid repellent material used in the present invention is not particularly limited as long as a desired liquid repellency can be exhibited when the light shielding portion is formed. Examples of such a liquid repellent material include a fluorine-containing compound and fine particles of a low surface energy substance.

Examples of the fluorine-containing compound include monomers or oligomers of compounds represented by the following formula (11) or (12).
General formula (11): Rf-X-Rf '
Formula (12): (Rf-XR) -Y- (R'-X'-Rf ')
In the above formula (11) or (12), Rf and Rf ′ represent a fluoroalkyl group, R and R ′ represent an alkylene group, Rf and Rf ′, and R and R ′ may be the same or different. good. X, X ′ and Y are —COO—, —OCOO—, —CONR ″ —, —OCONR ″ —, —SO ₂ NR ″ —, —SO ₂ —, —SO ₂ O—, —O—, It represents any one of —NR ″ —, —S—, —CO—, OSO ₂ O—, —OPO (OH) O—, and X, X ′ and Y may be the same or different. R ″ represents an alkyl group or hydrogen.
In addition, as the fluorine-containing compound, polytetrafluoroethylene, perfluoroethylenepropylene resin, perfluoroalkoxy resin, or the like can also be used.

  On the other hand, examples of the fine particles of the low surface energy material include fine particles composed of polyvinylidene fluoride, a fluoroolefin vinyl ether copolymer, a trifluoroethylene-vinylidene fluoride copolymer, and silicone fine particles. it can.

  The method for producing the light shielding part is not particularly limited as long as it can form the light shielding parts arranged in a desired manner. As such a method, for example, a method of forming by a sputtering method using a metal such as chromium, a photolithography method using a resin composition containing light shielding particles, and the above resin composition were used. The thermal transfer method etc. can be mentioned. In addition, an ink-jet ink for color filter according to the present invention, which is prepared by blending light-shielding particles such as a black pigment, is prepared, and the ink for forming the light-shielding part is applied to a predetermined region on the surface of the substrate. Alternatively, the light shielding portion may be formed by selectively attaching the ink layer by a method to form an ink layer in a predetermined pattern, curing the ink layer by a method such as ionizing radiation irradiation, and baking as necessary.

  The light-shielding portion is preferably provided to prevent the ink from being mixed when forming a colored layer to be a pixel portion by an inkjet method, and is preferably high to some extent. Considering the overall flatness, the thickness is preferably close to the thickness of the colored layer. The thickness of the light shielding part is appropriately selected and is not particularly limited. Specifically, the thickness is about 1000 to 2000 mm in the case of a metal thin film, and about 0.5 to 2.5 μm in the case of a light shielding resin layer.

(Pixel)
The pixel of the color filter according to the present invention is a cured film formed using the inkjet ink according to the present invention.
Since the pixel of the color filter according to the present invention is formed by curing the ink-jet ink for color filter according to the present invention, wrinkles and cracks are hardly generated as described above. Further, since the dispersibility of the pigment and the temporal stability of the pigment dispersion are excellent, the luminance and contrast of the pixel are improved. In addition, since the specific epoxy resin has an alicyclic skeleton, the yellowing resistance is improved as compared with the case of having an acrylic skeleton having a double bond or an aromatic ring skeleton. And a pixel with improved contrast performance.

  The pixel is preferably formed by an inkjet method using the inkjet ink according to the present invention. In the case of using the ink jet method, pixels can be formed with high definition, and there is an advantage that cost reduction and yield improvement can be realized.

Since the pixels of the color filter according to the present invention are usually formed using an inkjet method, the thickness tends to be non-uniform within the pixel region. That is, when a pixel is formed by an inkjet method in a region surrounded by the light-shielding part on the transparent substrate, the relationship between the ink and the surface of the light-shielding part, the height of the light-shielding part, the amount of ink to be ejected, etc. The shape of the pixel in the opening surrounded by the light-shielding portion has a portion with a small thickness along the outer edge portion of the pixel or in the vicinity thereof, and has a maximum thickness closer to the center of the pixel than the portion with the small thickness. Or a portion having a large thickness along the outer edge of the pixel or the vicinity thereof, and a minimum thickness portion on the center side of the pixel from the thick portion. And the surface tends to be uneven. Here, the outer edge portion of the pixel is an edge portion that defines the planar shape of the pixel. Further, “along the outer edge portion of the pixel or the vicinity thereof” means that it is only necessary to have a portion having a small thickness along at least a part of the outer edge portion or the vicinity thereof. The pixel thickness refers to the height from the substrate.
Since the pixel of the color filter according to the present invention is formed using the ink-jet ink having good pigment dispersibility according to the present invention, the pixel has a cross-sectional shape in which, for example, the vicinity of the central portion is raised as described above. Even in such a case, the luminance is high and the contrast is high.

A pixel is usually formed of three colors of red (R), green (G), and blue (B). The coloring pattern shape in the pixel can be a known arrangement such as a stripe type, a mosaic type, a triangle type, or a four-pixel arrangement type, and the coloring area can be arbitrarily set.
The thickness of the pixel is usually about 0.5 to 2.5 μm. Alternatively, the thickness of each color pixel may be changed so that the red pixel 7R is the thinnest, and the green pixel 7G and the blue pixel 7B become thicker in this order, and the optimum thickness may be set for each color.

(Protective film)
The protective film 8 is provided to flatten the surface of the color filter and prevent the components contained in the pixels 7 from eluting into the liquid crystal layer. The protective film 8 covers the light-shielding portion 6 and the pixels 7 with a known negative photocurable transparent resin composition or thermosetting transparent resin composition by a method such as spin coater, roll coater, spray, printing, etc. It can be formed by being applied to and cured by light or heat.
The thickness of the protective film 8 can be set in consideration of the light transmittance of the material used, the surface state of the color filter, and the like, and can be set in the range of 0.1 to 2.0 μm, for example.

(spacer)
A plurality of convex spacers are provided in a non-display area on the substrate in order to maintain a cell gap when the color filter 101 is bonded to a liquid crystal driving side substrate such as a TFT array substrate. The shape and size of the convex spacer are not particularly limited as long as it can be selectively provided in a non-display region on the substrate and can maintain a predetermined cell gap over the entire substrate. When the columnar spacer 12 as shown in the figure is formed as the convex spacer, it has a certain height in the range of about 2 to 10 μm, and the protruding height (pattern thickness) is required for the liquid crystal layer. It can set suitably from thickness etc. Moreover, the thickness of the columnar spacer 12 can be appropriately set within a range of about 5 to 20 μm. Further, the formation density (density) of the columnar spacers 12 can be appropriately set in consideration of the thickness unevenness of the liquid crystal layer, the aperture ratio, the shape and material of the columnar spacers, for example, red, green and blue Necessary and sufficient spacer function is expressed at a ratio of one for each pixel. The shape of such a columnar spacer may be a columnar shape, and may be, for example, a columnar shape, a prismatic shape, a truncated cone shape, or the like.

  The convex spacer is, for example, applied by applying a coating solution of the curable resin composition directly on the transparent substrate by a method such as spin coater, roll coater, spray, printing, or through another layer such as a transparent electrode. And dried to form a curable resin layer. The rotational speed of the spin coater may be set within a range of 500 to 1500 revolutions / minute, as in the case of forming the protective film. Usually, a photocurable ink-jet ink is preferably used as the ink-jet ink for forming the spacer. Next, the resin layer is exposed through a photomask for a convex spacer, and then a developer such as an alkaline liquid is used. Development is performed to form a predetermined convex pattern, and this convex pattern is heat-treated (post-baked) in a clean oven or the like as necessary to form a convex spacer.

  The convex spacer can be provided directly on the color filter or indirectly through another layer. For example, a transparent electrode such as ITO or a protective film may be formed on the color filter, and a convex spacer may be formed thereon, or a protective film and a transparent electrode may be formed on the color filter in this order, and the transparent electrode A convex spacer may be formed on the top.

(Transparent electrode)
The transparent electrode 9 can be formed using indium tin oxide (ITO), zinc oxide (ZnO), tin oxide (SnO), or an alloy thereof. The thickness of the transparent electrode can be about 20 to 500 nm, preferably about 100 to 300 nm.

(Other layers)
Other members usually formed on the color filter may be further included. For example, other members such as an alignment film can be formed by a usual method using those usually used for a color filter.

(Color filter manufacturing method)
The color filter manufacturing method preferably includes a colored layer forming step of forming the colored layer by selectively attaching the color filter inkjet ink according to the present invention to a predetermined region on the substrate by an inkjet method.
A desired pigment such as R, G, B or black is blended with the color filter ink-jet ink of the present invention, and the color filter ink-jet ink is selectively attached to a predetermined region on the substrate of the color filter by an ink-jet method. By forming an ink layer and curing the ink layer, a colored layer such as a pixel portion or a light shielding layer can be formed.
Since the color filter manufacturing method uses an inkjet method, cost reduction and yield improvement can be realized, and the manufacturing method is highly productive.

  The method for selectively depositing ink by the ink jet method is not particularly limited as long as it can form a colored layer having a desired thickness in a predetermined region on the substrate. As such a method, a method is generally used in which an inkjet head is used and the inkjet ink for a color filter is dropped onto a predetermined region on the substrate while moving the inkjet head or the substrate.

  The ink jet head is not particularly limited as long as a desired amount of ink jet ink can be dropped onto the surface of the base material in the opening provided in the light shielding portion described later. As such an inkjet head, for example, a discharge type that discharges charged inkjet ink continuously and controls the discharge amount by a magnetic field, a discharge type that discharges inkjet ink intermittently using a piezoelectric element, Alternatively, it is possible to use a general ink jet head such as a discharge type that heats ink jet ink and intermittently discharges using the foaming phenomenon.

An example of the manufacturing method of the color filter will be described with reference to FIG.
First, the color filter substrate having the color filter inkjet ink according to the present invention of each color for forming red, green, and blue colored layers as pixels, and the light shielding portion 2 formed on the substrate 1. 3 is prepared. Then, as shown in FIG. 2A, the colored layer forming regions 4R, 4G, and 4B of the respective colors defined in the color filter substrate 3 having the light shielding portion 2 formed on the base material 1 are formed. The ink layers are formed by spraying the respective colored layer forming inkjet inks of the corresponding colors by the inkjet method. In this ink spraying process, the color filter inkjet ink according to the present invention has high pigment dispersion stability over time, hardly increases in viscosity at the tip of the head 5, and can continue to maintain good ejection properties. . Therefore, the ink of the corresponding color can be adhered accurately and uniformly in the predetermined colored layer forming region, and a pixel portion with no color unevenness or color loss can be formed with an accurate pattern. Moreover, since the inkjet ink for color filters of each color can be simultaneously sprayed on a board | substrate using a some head, working efficiency can be improved compared with the case where a colored layer is formed for every color.

  Next, as shown in FIG. 2B, the ink layers 6R, 6G, and 6B of the respective colors are dried and pre-baked as necessary, and then cured by appropriate exposure and / or heating. In particular, in the present invention, it is preferable that the method further includes a step of drying the ink layer under reduced pressure before the normal pre-bake stage, because the surface shape of the ink layer can be improved. Examples of the conditions for drying under reduced pressure include drying under reduced pressure at 0.1 to 20 Torr for 1 to 20 minutes. At that time, it is preferable to control the substrate temperature within a temperature range of 20 ° C to 60 ° C. Then, after drying under reduced pressure, for example, prebaking is performed on a hot plate at 60 to 165 ° C. for 3 to 80 minutes. Moreover, you may perform a heating and pressure reduction drying simultaneously. Thereafter, when the ink layer is appropriately exposed and / or heated, the curable resin contained in the inkjet ink undergoes a crosslinking reaction, and the ink layer is cured to form pixel portions (7R, 7G, 7B) that are colored layers.

Next, as shown in FIG. 2C, the protective layer 8 is formed on the side of the transparent substrate where the pixel portions (7R, 7G, 7B) are formed.
In addition, on the protective film, a transparent electrode film is formed using indium tin oxide (ITO), zinc oxide (ZnO), tin oxide (SnO), or an alloy thereof, a sputtering method, a vacuum evaporation method, a CVD method, or the like. It is formed by a general method such as a method (not shown). If necessary, a predetermined pattern can be obtained by etching using a photoresist or using a jig. The thickness of the transparent electrode is about 20 nm to 500 nm, preferably about 100 to 300 nm.

  In the production of the color filter of the present invention, the process for forming the transparent electrode film includes the heating process at a high temperature of 180 ° C. or higher, because the inkjet ink for a color filter according to the present invention is used. In the transparent electrode film, wrinkles and cracks are unlikely to occur. The surface roughness (Ra) of the transparent electrode film obtained by the production of the color filter of the present invention is preferably 10 nm or less, more preferably 8 nm or less. Here, the surface roughness (Ra) refers to the arithmetic average roughness obtained by the following formula.

In the formula, N is the number of divisions with respect to the reference length at the time of measurement, and Rn is a deviation from the average height of the divided sections n when the thickness direction with respect to the surface is height. The surface roughness (Ra) can be measured by an AFM (atomic force microscope).
In others, it can manufacture using the method similar to the method of forming a normal color filter.

The color filter manufacturing method of the present invention may further include other steps. Such other steps can be arbitrarily determined according to the use of the color filter produced according to the present invention. In particular, in the present invention, before the colored layer (pixel portion) forming step. It is preferable to have a lyophilic step of making the surface of the base material used for the color filter substrate lyophilic. By having such a lyophilic step, it becomes easy to uniformly spread the ink-jet ink in the opening surrounded by the light-shielding part, so that it is possible to prevent a portion where no colored layer is formed in the opening. Because.
Hereinafter, the lyophilic process used in the present invention will be described.

  The method for making the surface of the substrate lyophilic in the lyophilic step used in the present invention is not particularly limited as long as it can improve the lyophilicity of the surface of the substrate with respect to the inkjet ink. Examples of such a method include a method of forming a highly lyophilic layer on the surface of the substrate and a method of increasing the liquid repellency of the substrate surface itself.

  The method for forming the highly lyophilic layer on the substrate surface is not particularly limited as long as it can form a layer showing a desired lyophilic property with respect to the inkjet ink on the substrate surface. In particular, in this step, after forming a photocatalyst and a photocatalyst-containing layer containing an organopolysiloxane so as to cover the light shielding portion of the color filter substrate and the surface of the base material, a method of irradiating energy from the base material side. Can be mentioned. According to such a method, the photocatalyst-containing layer has a function of reducing the contact angle with the liquid by the action of the photocatalyst accompanying energy irradiation, and by performing energy irradiation from the substrate side, Since energy irradiation can be performed only on the photocatalyst-containing layer formed on the opening, only the photocatalyst-containing layer formed on the substrate surface can improve the lyophilicity with respect to the inkjet ink. A photocatalyst-containing layer having excellent wettability with respect to the inkjet ink can be formed on the substrate surface.

  Here, the photocatalyst-containing layer, the energy irradiation method, and the like can be the same as those described in Japanese Patent Application Laid-Open No. 2004-361426, and thus detailed description thereof is omitted here.

  On the other hand, examples of a method for increasing the lyophilicity of the surface of the substrate itself include a method of irradiating the substrate surface with plasma or the like. The method of irradiating such plasma is not particularly limited as long as it is a method that can remove the residue present on the base material in the opening of the light-shielding portion by dry etching. Generally, organic materials are removed by dry etching. A plasma irradiation method used for removal can be used. In particular, in this step, it is desirable to use a method in which plasma is irradiated in the presence of oxygen and at least one gas selected from the group consisting of nitrogen, helium, or nitrogen as the plasma irradiation method.

  The degree of lyophilicity of the substrate surface in the lyophilic step used in the present invention is preferably such that the contact angle with a liquid having a surface tension of 40 mN / m is less than 10 °, particularly the surface. The contact angle with a liquid having a tension of 50 mN / m is preferably about 10 ° or less, and in particular, the contact angle with a liquid having a surface tension of 60 mN / m is preferably about 10 ° or less.

In addition to the lyophilic step, another step used in the present invention may include a lyophobic step of lyophobizing the light shielding portion of the color filter substrate before the colored layer forming step. By having such a liquid repellency step, the ink jet ink discharged to the opening surrounded by the light shielding part can be effectively prevented from leaking to the adjacent opening. It is possible to prevent color mixing in the filter.
Hereinafter, such a liquid repellency process will be described.

In the liquid repellency process used in the present invention, the method of making the light shielding part liquid repellent can make the liquid shielding property of the light shielding part relatively higher than the liquid repellency of the substrate surface used for the color filter substrate. The method is not particularly limited. Here, the liquid repellency means liquid repellency with respect to the inkjet ink.
Examples of such a liquid repellency method include a method of increasing the liquid repellency of the light shielding part itself and a method of forming a layer having a high liquid repellency on the light shielding part.

  Examples of a method for increasing the liquid repellency of the light shielding part itself include a method of introducing fluorine into the light shielding part. Such a method is not particularly limited as long as it is a method capable of relatively introducing a larger amount of fluorine into the light shielding portion than the substrate surface in the opening, but for example, a material constituting the light shielding portion. And a method of irradiating plasma using a fluorine compound as an introduction gas from above the light shielding part, using a resin material and a color filter substrate using an inorganic material as a material constituting the substrate. it can. In such a method, the fluorine compound can be introduced only into the organic substance, and as a result, fluorine can be selectively introduced only into the light shielding portion. As a result, the liquid repellency of the light shielding portion can be made higher than that of the substrate surface in the opening. Can also be easily increased.

Here, the presence of fluorine in the light-shielding part when the plasma irradiation is performed is present in all the elements detected from the surface of the light-shielding part in the analysis by an X-ray photoelectron spectrometer (XPS: ESCALAB 220i-XL). This can be confirmed by measuring the ratio of the fluorine element.
Further, examples of the fluorine compound of the introduction gas used for the plasma irradiation include carbon fluoride (CF ₄ ), fluorine nitride (NF ₃ ), sulfur fluoride (SF ₆ ), and the like.

  The plasma irradiation method is not particularly limited as long as it can irradiate the plasma using a fluorine compound as an introduction gas and make the light shielding part liquid repellent. Plasma irradiation is performed under reduced pressure. Alternatively, plasma irradiation may be performed under atmospheric pressure. Among these, in the present invention, it is particularly preferable that the plasma irradiation is performed under atmospheric pressure. This is because an apparatus for decompression or the like is not necessary, which can be preferable in terms of cost, manufacturing efficiency, and the like.

Examples of the atmospheric pressure plasma irradiation conditions include the following. The power output can be the same as that used in a general atmospheric pressure plasma irradiation apparatus. At this time, the distance between the irradiated plasma electrode and the light shielding portion is preferably about 0.2 mm to 20 mm, and more preferably about 0.4 mm to 5 mm.
The flow rate of the fluorine compound used as the introduction gas is preferably in the range of 1 L / min to 100 L / min, and more preferably in the range of 3 L / min to 50 L / min.

  On the other hand, the method for forming a layer having high liquid repellency on the light shielding part is particularly limited as long as it can form a layer having relatively higher liquid repellency on the light shielding part than the surface of the substrate. Is not to be done. Examples of such a method include a method of forming the above-described photocatalyst-containing layer.

  In the liquid repellency step, the degree of repellency of the light shielding portion is not particularly limited as long as the liquid repellency is relatively higher than that of the opening. In particular, in the present invention, the contact angle with a liquid having a liquid repellency of 40 mN / m is preferably about 10 ° or more, and the contact angle with a liquid having a surface tension of 30 mN / m is particularly 10 ° or more. It is preferable that the contact angle with a liquid having a surface tension of 20 mN / m is 10 ° or more. Moreover, it is preferable that the contact angle with pure water is about 11 ° or more.

  On the other hand, the liquid repellency of the opening is not particularly limited as long as it is lower than the liquid repellency of the light shielding part, but it is preferable that the contact angle with a liquid of 40 mN / m is less than 10 °. In particular, the contact angle with a liquid having a surface tension of 50 mN / m is preferably about 10 ° or less, and further the contact angle with a liquid having a surface tension of 60 mN / m is about 10 ° or less. preferable.

  In addition, the contact angle with the liquid is measured using a contact angle measuring device (CA-Z type manufactured by Kyowa Interface Science Co., Ltd.) with a liquid having various surface tensions. The value taken 30 seconds after dropping) is used. Further, as the liquid having various surface tensions used for the measurement, a wetting index standard solution manufactured by Junsei Chemical Co., Ltd. is used.

  In others, it can manufacture using the method similar to the method of forming a normal color filter.

4). Furthermore, the liquid crystal display device according to the present invention is a liquid crystal display device in which a display side substrate and a liquid crystal driving side substrate are opposed to each other, and liquid crystal is sealed between the two, and the display side substrate is It is a color filter according to the present invention.
Since the liquid crystal display device according to the present invention uses a high-luminance color filter with reduced display defects as described above, it can be a high-quality and highly productive liquid crystal display device.

When the color filter 101 (display side substrate) and the TFT array substrate (liquid crystal driving side substrate) obtained as described above are opposed to each other and the inner peripheral side edge portions of both the substrates are joined with a sealant, the two substrates are separated by a predetermined distance. Bonding is performed with the cell gap maintained. An active matrix color liquid crystal display device belonging to the liquid crystal display device according to the present invention can be obtained by filling the gap between the substrates with liquid crystal and sealing it.
Since other configurations and manufacturing methods in the liquid crystal display device can use commonly used configurations and methods, description thereof is omitted here.

The liquid crystal display device of the present invention is not particularly limited as long as it has the above-described color filter, and may be a known liquid crystal display device. Specifically, IPS (In-Plane Switching) type, STN (Super Twisted Nematic) type, TN (Twisted Nematic) type, ferroelectric type, antiferroelectric type, MVA mode type and the like can be mentioned.
The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

(Production Example 1: Production of Dispersion Auxiliary Resin 2)
134 g (1 mol) of trimethylolpropane and 3726 g (30 mol) of 4-vinylcyclohexene-1-oxide are mixed at 60 ° C., and the conversion of 4-vinylcyclohexene-1-oxide becomes 98% by gas chromatography analysis. Then, ethyl acetate was added to the resulting reaction solution and washed with water, and then the ethyl acetate layer was concentrated to obtain a viscous transparent solution. Further, 573 g of this compound was dissolved in ethyl acetate and charged into the reactor, and 387 g of peracetic acid was added dropwise as an ethyl acetate solution over 2 hours. During this time, the reaction temperature was kept at 40 ° C. After completion of the peracetic acid preparation, the mixture was further aged at 40 ° C. for 4 hours. Ethyl acetate was added to the reaction crude liquid, washed with alkaline water containing 416 g of sodium carbonate, and thoroughly washed with distilled water. The ethyl acetate layer was concentrated to obtain a viscous transparent liquid.

(Production Example 2: Production of dispersion auxiliary resin 3)
In the same manner as in Production Example 1, 25 g (1 mol) of allyl alcohol, 868 g (7 mol) of 4-vinylcyclohexene-1-oxide and 4.7 g of BF3 etherate were reacted to obtain a viscous liquid product. Further, in the same manner as in Production Example 1, 492 g of this compound was reacted with 395 g of peracetic acid to obtain a viscous transparent liquid.

(Production Example 3: Synthesis of binder epoxy compound)
In a four-necked flask equipped with a thermometer, reflux condenser, stirrer, and dropping funnel, the solvent diethylene glycol monobutyl ether acetate (also called butyl carbitol acetate, hereinafter referred to as BCA) does not contain a hydroxyl group according to the blending ratio shown in Table 1. 40.7 parts by weight were charged and heated with stirring to 140 ° C. Next, 54.7 parts by weight of a mixture (dropping component) of a monomer having a composition described in Table 1 and a polymerization initiator at 140 ° C. was dropped at a constant rate from a dropping funnel over 2 hours. After completion of the dropwise addition, the temperature was lowered to 110 ° C., 4.6 parts by weight of a mixture of polymerization initiator and solvent-free diethylene glycol monobutyl ether acetate (BCA) (additional catalyst component) was added, and the temperature at 110 ° C. was maintained for 2 hours. By the way, by terminating the reaction, a binder epoxy compound having the characteristics shown in Table 1 was obtained.

(Production Example 4: Synthesis of binder epoxy compound)
Except for changing the solvent diethylene glycol monobutyl ether acetate (also called butyl carbitol acetate, hereinafter may be referred to as BCA) to the solvent diethylene glycol monoethyl ether acetate (hereinafter sometimes referred to as ECA), Production Example 3 and Similarly, a binder epoxy compound was obtained.

* 1) Abbreviations in the table are as follows.
GMA: Glycidyl methacrylate MMA: Methyl methacrylate Perbutyl O: t-Butylperoxy 2-ethylhexanoate (trade name, manufactured by NOF Corporation)
* 2) Weight average molecular weight: A value in terms of polystyrene by gel permeation chromatography.

(Examples DB1 to DB4, Comparative examples DB1 to DB5: Blue inkjet ink for color filter (B15: 6) Pigment dispersion)
The pigment, pigment dispersant, pigment dispersion auxiliary resin and organic solvent are mixed in the proportions shown in Table 2, 300 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 Steel Corporation). Went. After dispersion, the mixture was filtered through a 5.0 micron membrane filter to obtain a blue (B15: 6) pigment dispersion.

* In Tables 2 to 10, the abbreviations are as follows.
Disperbyk2000: trade name, Disperbyk 161 manufactured by Big Chemie Japan Co., Ltd .: trade name, dispersion auxiliary resin manufactured by Big Chemie Japan Co., Ltd. 1: trade name EHPE-3150 (1 of 2,2-bis (hydroxymethyl) -1-butanol , 2-epoxy-4- (2-oxiranyl) cyclohexane adduct), average number of epoxy functional groups in the molecule (sum of n1 to nk) 15, epoxy equivalent 179 g / eq, dispersion auxiliary resin 2 manufactured by Daicel Chemical Industries, Ltd .: Production Example 1 (number of epoxy functional groups in the molecule (sum of n1 to nk) average 10), epoxy equivalent 182 g / eq
Dispersion auxiliary resin 3: Production Example 2 (number of epoxy functional groups in the molecule (sum of n1 to nk) average 7) epoxy equivalent 185 g / eq
YDPN-638: trade name, phenol novolac type epoxy resin, manufactured by Toto Kasei Co., Ltd., epoxy equivalent of 179 g / eq
SR-16H: trade name, 1,6-hexanediol type epoxy resin, manufactured by Sakamoto Pharmaceutical Co., Ltd., epoxy equivalent 157 g / eq
EPPN-502H: trade name, trisphenol methane type epoxy resin, manufactured by Nippon Kayaku Kogyo Co., Ltd., epoxy equivalent 168 g / eq
jERYX-4000: trade name, biphenyl type epoxy resin, manufactured by Japan Epoxy Resin Co., Ltd., epoxy equivalent 180-192 g / eq
BCA: Diethylene glycol monobutyl ether acetate ECA: Diethylene glycol monoethyl ether acetate EEP: Ethyl 3-ethoxypropionate

[Evaluation]
About the obtained pigment dispersion, the pigment dispersibility and the pigment dispersion temporal stability were examined according to the following methods. The results are also shown in Table 2.
1. Average particle size The average particle size was measured immediately after the preparation of each pigment dispersion and after one week. The average particle size was measured at 23 ° C. by dynamic light scattering using a particle size distribution meter (MICROTRAC UPA, manufactured by Nikkiso Co., Ltd.) after each pigment dispersion was diluted 100 times with each main solvent. It was measured as 360 seconds. The average particle diameter here is a 50% average particle diameter, that is, a volume-based median diameter.

2. viscosity
Immediately after the preparation of each pigment dispersion and after 1 day and 1 week after storage at 25 ° C. in a sealed container, the viscosity was measured. The viscosity was measured at 23 ° C. with a rotational vibration type viscometer Viscomate VM-1G manufactured by Yamaichi Electronics.

(Examples DB5 to DB8, Comparative Examples DB6 to DB10: (V23) pigment dispersion for blue inkjet ink for color filter)
The pigment, pigment dispersant, pigment dispersion auxiliary resin and organic solvent are mixed in the proportions shown in Table 3, 300 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 Steel Corporation) Went. After the dispersion, the mixture was filtered through a 5.0 micron membrane filter to obtain a blue (V23) pigment dispersion.

  From the results of Tables 2 and 3, Examples DB1 to DB8 in which pigment dispersions were prepared using the dispersion assisting resin according to the present invention were excellent in pigment dispersibility and stability with time of the pigment dispersion. On the other hand, Comparative Examples DB1, DB2, DB4, DB6, DB7, DB9 using a dispersion auxiliary resin different from the present invention, and Comparative Examples DB5 and DB10 using no dispersion auxiliary resin are pigment dispersibility and pigment dispersion. The stability over time was inferior. On the other hand, Comparative Examples DB3 and DB8 were excellent in pigment dispersibility and stability with time of the pigment dispersion.

(Examples DR1 to DR9, Comparative Examples DR1 to DR6: Pigment dispersion liquid for red inkjet ink for color filter)
Pigment, pigment dispersant, pigment dispersion auxiliary resin and organic solvent are mixed in the proportions shown in Table 4, 300 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 Steel Corporation). Went. After dispersion, the mixture was filtered through a 5.0 micron membrane filter to obtain a pigment dispersion for red inkjet ink.

  From the results of Table 4, Examples DR1 to DR9, in which pigment dispersions were prepared using the dispersion assisting resin according to the present invention, were excellent in pigment dispersibility and stability with time of the pigment dispersion. On the other hand, Comparative Examples DR1 to DR6 using a dispersion auxiliary resin different from the present invention were inferior in pigment dispersibility and stability with time of the pigment dispersion.

(Examples DG1 to DG12, Comparative Examples DG1 to DG8: Pigment dispersion for green inkjet ink for color filter)
A pigment, a pigment dispersant, a pigment dispersion auxiliary resin, and an organic solvent are mixed in the proportions shown in Tables 5 and 6, 300 parts by weight of zirconia beads having a diameter of 0.5 mm are added, and a paint shaker (manufactured by Asada Steel Corporation) is used. Dispersion was performed for 3 hours. After dispersion, the mixture was filtered through a 5.0 micron membrane filter to obtain a pigment dispersion for green inkjet ink.

  From the results of Tables 5 and 6, Examples DG1 to DG12, in which pigment dispersions were prepared using the dispersion assisting resin according to the present invention, were excellent in pigment dispersibility and temporal stability of the pigment dispersion. On the other hand, Comparative Examples DG1 to DG8 using a dispersion auxiliary resin different from the present invention were inferior in pigment dispersibility and stability with time of the pigment dispersion.

(Examples B1 to B7 and Comparative Examples B1 to B10: Preparation of blue inkjet ink for color filter)
(1) Preparation of thermosetting binder solution A Teflon (registered trademark) -coated rotor was placed in a sample bottle and placed on a magnetic stirrer. In this sample bottle, the binder epoxy compound described in Production Example 3 and the polyfunctional epoxy resin are added according to the following ratio, and sufficiently stirred and dissolved at room temperature. Then, the diluent BCA is added to adjust the viscosity. In addition, after stirring and dissolving, this was filtered to obtain a binder composition. In Example B4, the binder epoxy compound of Production Example 4 was used in place of the binder epoxy compound of Production Example 3, and ECA (diethylene glycol monoethyl ether) was used as a diluent solvent instead of BCA (diethylene glycol monobutyl ether acetate). Acetate) was used.
[Blend ratio of thermosetting binder solution]
-Binder epoxy compound of Production Example 3 (solid content 30% by weight in solvent BCA): 62.5 parts by weight-Multifunctional epoxy resin (trade name jER157S70, manufactured by Japan Epoxy Resins Co., Ltd.): 12.5 parts by weight Neopentyl glycol glycidyl ether: 6.25 parts by weight Trimellitic acid: 12.5 parts by weight BCA (diethylene glycol monobutyl ether acetate): 6.25 parts by weight

(2) Preparation of photocurable and thermosetting binder solution A Teflon (registered trademark) -coated rotor was placed in a sample bottle and placed in a magnetic stirrer. In this sample bottle, add a copolymer, polyfunctional acrylate, etc. according to the following ratio, stir and dissolve thoroughly at room temperature, then add a diluting solvent to adjust the viscosity, stir and dissolve, and filter this. Thus, a binder composition was obtained.
[Blending ratio of light and thermosetting binder solution]
Benzyl methacrylate-methacrylic acid copolymer (trade name Aronix M-308, manufactured by Toa Gosei Chemical Co., Ltd.): 14.4 parts by weight Pentaerythritol tetraacrylate (trade name Aronix M-450, Toa Gosei Chemical Co., Ltd.) Product: 3.2 parts by weight-dipentaerythritol pentaacrylate (trade name KAYARAD SR-399E, manufactured by Nippon Kayaku Co., Ltd.): 5.1 parts by weight-polymerization initiator (trade name: Irgacure 369, manufactured by Ciba Specialty Chemicals) : 5.1 parts by weight maleic anhydride: 0.6 parts by weight polyfunctional epoxy resin (trade name jER157S70, manufactured by Japan Epoxy Resin Co., Ltd.): 1.6 parts by weight BCA (diethylene glycol monobutyl ether acetate) or ECA (Diethylene glycol monoethyl ester Ether acetate): 70 parts by weight

(3) Preparation of inkjet ink The blue pigment dispersions of Examples DB1 to DB8 or Comparative Examples DB1 to DB10 obtained above so as to have the blending ratios shown in Table 7 and Table 8, and the above A thermosetting binder solution, or the above light and thermosetting binder solution, and a solvent were further added and mixed well to obtain blue inkjet inks for color filters of Examples B1 to B7 and Comparative Examples B1 to B10.

[Evaluation method]
<Creation of coating film for evaluation>
The coating film for evaluating using each inkjet ink was created.
On a glass substrate having a thickness of 0.7 mm (NA Techno Glass Co., Ltd., NA35), the dry film thickness by spin coating is 1.61 μm for red inkjet ink, and 1.65 μm for green and blue inkjet inks. Each inkjet ink was applied.
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.

1. ITO resistance The substrate on which the coating film for evaluation was formed using the blue inkjet ink was immersed in isopropyl alcohol for 5 minutes, then dried with isopropyl alcohol vapor, washed, and then heated 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 × 10 −3 Torr. After the heat resistance test at 180 ° C. for 60 minutes, the evaluation was made according to the following criteria. Further, the surface roughness (Ra) of the formed 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.

2. Yellowing The substrate on which the ejection film for evaluation was formed using the blue inkjet ink was heated at 240 ° C. for 1 hour, and the color difference ΔEab before and after heating was calculated based on the CIE 1976 standard and evaluated. The measurement of the color difference ΔEab was performed using a microspectrophotometer OSP200 manufactured by Olympus Optical Co., Ltd.
[Evaluation criteria]
○: ΔEab <3
×: 3 ≦ ΔEab

3. Adhesion The substrate on which the coating film for evaluation was formed using the blue ink-jet ink was cut into 11 vertical and horizontal cuts at 1 mm intervals perpendicular to each other with a cutter. Furthermore, the cellophane tape was lightly adhered to the pattern with a finger, the tape was quickly peeled off, the state of the wound was observed, and the determination was made according to the following criteria.
[Evaluation criteria]
8 points: There is slight peeling at the line of cuts, and the area of the defect is less than 5% of the total square area.
6 points: There is peeling at the intersection of the cuts, and the area of the missing part is 5% or more and less than 15% of the total square area.
4 points: The width of peeling due to cuts is wide, and the area of the defect is 15% or more and less than 35% of the total square area.
2 points: The width of peeling due to cuts is wider than 4 points, and the area of the missing part is 35% or more and less than 65% of the total square area.
0 point: The area of peeling is 65% or more of the total square area.

4). Solvent Resistance The substrate on which the coating film for evaluation was formed using the blue inkjet ink was immersed in N-methylpyrrolidone at a liquid temperature of 40 ° C. for 1 hour, and the color difference ΔEab before and after immersion was calculated based on the CIE 1976 standard. The measurement was performed using a microspectrophotometer OSP200 manufactured by Olympus Optical Co., Ltd.
[Evaluation criteria]
○: ΔEab <1
Δ: 1 ≦ ΔEab <3
×: 3 ≦ ΔEab

5. Ink storage stability The viscosity and average particle diameter were measured immediately after the preparation of each ink-jet ink and after 1 month storage at 25 ° C. in a sealed container. The viscosity and average particle size were measured in the same manner as the pigment dispersion.

* When showing the composition of the ink, the pigment dispersion, binder component, etc. displayed only parts by weight of the solid content, and all the solvents contained in the ink were counted at the bottom.
From the results of Tables 7 and 8, Examples B1 to B7, which are ink jet inks prepared with a pigment dispersion using the dispersion auxiliary resin according to the present invention, are excellent in pigment dispersibility and ink aging stability. there were. In addition, it was excellent in yellowing resistance, excellent in solvent resistance and adhesion of the cured film, and even when an ITO film was formed under ultra-low pressure and high temperature, wrinkles and cracks did not occur in the ITO film, and film properties were good .
On the other hand, Comparative Examples B5 and B10 in which no dispersion auxiliary resin was used were considerably inferior in pigment dispersibility and ink aging stability. In Comparative Examples B5 and B10, when the ITO film was formed under ultra-low pressure and high temperature, wrinkles and cracks were generated in the ITO film, and the cured film had poor solvent resistance and adhesion, and the film properties were poor. It was.
Further, Comparative Examples B1 to B4 and B6 to B9 using a dispersion auxiliary resin different from the present invention are all yellowing resistant and / or ITO resistant, adhesiveness, solvent resistance, pigment dispersibility, and ink. The stability over time was inferior.
Moreover, the photograph of the coating-film surface for evaluation of Example B1 after ITO tolerance evaluation is shown in FIG. 3, and the photograph of the coating-film surface for evaluation of comparative example B5 after ITO tolerance evaluation is shown in FIG.

(Examples R1 to R3 and Comparative Examples R1 to R2: Preparation of red inkjet ink for color filter)
The binder solution having the same composition as the binder solution used in the blue inkjet ink of Example B1 was used. In Example R3, the binder epoxy compound of Production Example 4 is used instead of the binder epoxy compound of Production Example 3, and ECA (diethylene glycol monoethyl ether acetate) is used instead of BCA (diethylene glycol monobutyl ether acetate). Using.
Examples R1 to R3 having the blending ratios shown in Table 9 by adding the above-described red pigment dispersions of Examples and Comparative Examples, the binder solution, and further adding a solvent and mixing well. And the red inkjet ink for color filters of Comparative Examples R1-R2 was obtained.

* When showing the composition of the ink, the pigment dispersion, binder component, etc. displayed only parts by weight of the solid content, and all the solvents contained in the ink were counted at the bottom.
From the results of Table 9, Examples R1 to R3, which are inkjet inks prepared with a pigment dispersion using the dispersion assisting resin according to the present invention, were excellent in pigment dispersibility and ink aging stability. In addition, it was excellent in yellowing resistance, excellent in solvent resistance and adhesion of the cured film, and even when an ITO film was formed under ultra-low pressure and high temperature, wrinkles and cracks did not occur in the ITO film, and film properties were good .
On the other hand, Comparative Examples R1 and R2 using a dispersion auxiliary resin different from the present invention are all yellowing resistant and / or ITO resistant, adhesiveness, solvent resistance, pigment dispersibility, and ink stability over time. The property was inferior.
Moreover, the photograph of the coating film surface for evaluation of Example R1 after ITO tolerance evaluation is shown in FIG. 5, and the photograph of the coating film surface for evaluation of Comparative Example R2 after ITO resistance evaluation is shown in FIG.

(Examples G1-G3 and Comparative Examples G1-G2: Preparation of green inkjet ink for color filter)
The binder solution having the same composition as the binder solution used in the blue inkjet ink of Example B1 was used. In Example G3, the binder epoxy compound of Production Example 4 was used in place of the binder epoxy compound of Production Example 3, and ECA (diethylene glycol monoethyl ether acetate) was used instead of BCA (diethylene glycol monobutyl ether acetate). Using.
Examples G1 to G3 having the blending ratios as shown in Table 10 by adding the green pigment dispersions of Examples and Comparative Examples obtained above, the binder solution, and further adding a solvent and mixing well. And the green inkjet ink for color filters of Comparative Examples G1-G2 was obtained.

* When showing the composition of the ink, the pigment dispersion, binder component, etc. displayed only parts by weight of the solid content, and all the solvents contained in the ink were counted at the bottom.
From the results of Table 10, Examples G1 to G3, which are inkjet inks prepared with a pigment dispersion using the dispersion auxiliary resin according to the present invention, were excellent in pigment dispersibility and ink aging stability. In addition, it was excellent in yellowing resistance, excellent in solvent resistance and adhesion of the cured film, and even when an ITO film was formed under ultra-low pressure and high temperature, wrinkles and cracks did not occur in the ITO film, and film properties were good .
On the other hand, Comparative Examples G1 and G2 using a dispersion auxiliary resin different from the present invention are all yellowing resistant and / or ITO resistant, adhesiveness, solvent resistance, pigment dispersibility, and ink stability over time. The property was inferior.
Moreover, the photograph of the coating film surface for evaluation of Example G1 after ITO tolerance evaluation is shown in FIG. 7, and the photograph of the coating film surface for evaluation of Comparative Example G2 after ITO resistance evaluation is shown in FIG.

(Evaluation of brightness and contrast of inkjet ink)
The blue inkjet inks of Examples B1, B2 and Comparative Examples B1, B2 obtained above; the red inkjet inks of Examples R1, R2 and Comparative Examples R1, R2; the green colors of Examples G1, G2 and Comparative Examples G1, G2 The inkjet ink was evaluated for brightness and contrast as follows. Table 11 shows the evaluation results.

[Evaluation method]
A coating film for evaluation (colored layer) was prepared in the same manner as above using each inkjet ink.
(1) Luminance The luminance was measured using a microspectrophotometer (manufactured by Olympus Corporation, OSP200).

(2) Contrast A polarizing film 43 (NPF-SEG1425DU manufactured by Nitto Denko) was bonded to a 0.7 mm thick glass substrate (NA Techno Glass Co., Ltd., NA35) 40 to form a polarizing plate 43. As shown in FIG. 9, two polarizing plates 43 are sandwiched so that the polarizing film 42 is on the outside of the glass substrate 40 on which the colored layer 41 is formed, so that the polarizing film 42 is on the outside. A measurement sample 44 was obtained. In the configuration of the measurement sample 44, the distance l ₁ between the polarizing plate 43 and the colored layer 41 was 9.3 mm, and the distance l ₂ between the polarizing plate 43 and the glass substrate 40 was 0 mm.
As shown in FIG. 10, luminance measurement was performed in contrast measurement. A backlight 45 was lit on the measurement sample 44, and the luminance was measured. A measurement sample was prepared by setting the polarizing plates orthogonally and then in parallel, and each luminance was measured. The contrast value was calculated by the luminance when parallel to the luminance when orthogonal (luminance when parallel / luminance when orthogonal). The position where the luminance was measured in the sample was a position where the film thickness was uniform in the color filter layer. As a device 46 for measuring luminance in contrast measurement, a luminance meter (LS-100 manufactured by Konica Minolta Sensing Co., Ltd.) equipped with a close-up lens (No. 153) 47 was used. The viewing angle of the luminance meter was 1 °. The distance L from the close-up lens 47 to the measurement sample 44 was 710 mm.

  From the results of Table 11, Examples B1, B2, R1, R2, G1, and G2, which are inkjet inks prepared with a pigment dispersion using the dispersion assisting resin according to the present invention, all have pigment dispersibility and ink. Thus, the brightness and contrast of the cured film were improved. On the other hand, Comparative Examples B1, B2, R1, R2, G1, and G2 using a dispersion auxiliary resin different from the present invention were inferior in brightness and contrast of the cured film as compared with the Examples. .

(Example 1: Production of color filter)
By preparing EAGLE 2000 made by Corning having a thickness of 0.7 mm, a width of 370 mm, and a length of 470 mm, which is used as a glass material for a color filter, and forming a resin black matrix on this glass substrate by photolithography A color filter substrate was prepared. At this time, the black matrix is formed so that the opening is 100 μm × 300 μm and the line width of the light-shielding portion is 20 μm, and the vertical matrix is arranged at 120 μm pitch and 320 μm pitch in the vertical direction with 480 pixels and 1320 pixels in the horizontal direction. It was supposed to be. At this time, the thickness of the light shielding portion was set to an average of 2.2 μm.
By applying a plasma treatment using a fluorine compound as an introduction gas to the color filter substrate, the surface of the black matrix was made lyophobic and the other region (colored layer forming region) was made lyophilic. At this time, the contact angle with a liquid having a surface tension of 40 mN / m was measured using a contact angle measuring device (CA-Z type manufactured by Kyowa Interface Chemical Co., Ltd.). It was 9 °.

The blue inkjet ink of Example B1 was adhered accurately and uniformly to the blue pixel forming portion partitioned by the light shielding portion of the substrate by the inkjet method. Next, the green inkjet ink of Example G1 was accurately and uniformly attached to the green pixel forming portion of the same substrate by the inkjet method. Next, the red inkjet ink of Example R1 was accurately and uniformly attached to the red pixel forming portion of the same substrate by the inkjet method.
Then, it dried under reduced pressure on a 25 degreeC hotplate for 120 seconds at 10 Torr, and also prebaked for 10 minutes on the 80 degreeC hotplate. Then, in a clean oven, post-baking is performed by heating at 200 ° C. for 30 minutes, and further, post-baking is performed by heating at 240 ° C. for 30 minutes. The average film thickness after drying and curing on the substrate is 2. An RGB three-color pixel pattern having 1 μm and G and B of 2.15 μm was formed. The average film thickness is measured by measuring the film thickness of all areas of the pixel formation area (1 pixel) every 1 μm using an optical interference type 3D non-contact surface shape measuring device (product name: Micromap557N manufactured by Micromap USA). Is the average.

The substrate on which the RGB pixel pattern was formed was immersed in IPA for 5 minutes, then dried by IPA vapor, washed, and then ITO (indium oxide) at a substrate setting temperature of 200 ° C. under a vacuum of 6 × 10 ⁻³ Torr. A tin) electrode was deposited to a thickness of 120 nm. The substrate on which this ITO film was formed was further immersed in IPA for 5 minutes, steam-washed with IPA, spin-coated with polyimide, and baked at 180 ° C. for 60 minutes to form an alignment film. Got.

It is a typical longitudinal section showing an example of a color filter concerning the present invention. It is a figure explaining an example of the method of manufacturing a color filter using the inkjet ink of this invention. It is a photograph which shows the coating-film surface for evaluation of Example B1 after ITO tolerance evaluation. It is a photograph which shows the coating-film surface for evaluation of comparative example B5 after ITO tolerance evaluation. It is a photograph which shows the coating-film surface for evaluation of Example R1 after ITO tolerance evaluation. It is a photograph which shows the coating-film surface for evaluation of comparative example R2 after ITO tolerance evaluation. It is a photograph which shows the coating-film surface for evaluation of Example G1 after ITO tolerance evaluation. It is a photograph which shows the coating-film surface for evaluation of the comparative example G2 after ITO tolerance evaluation. It is a figure explaining the sample in the measurement of contrast in the present invention. It is a figure explaining the measuring method of contrast in the present invention.

Explanation of symbols

101 Color filter 1 Transparent substrate 2 Light-shielding portion 3 Color filter substrate 6 (6R, 6G, 6B) Ink layer 7 (7R, 7G, 7B) Colored layer (pixel portion)
DESCRIPTION OF SYMBOLS 8 Protective film 9 Transparent electrode film 10 Orientation film 12 Columnar spacer 40 Glass substrate 41 Colored layer 42 Polarizing film 43 Polarizing plate 44 Measurement sample 45 Backlight 46 Apparatus for measuring luminance 47 Close-up lens

Claims (6)

A pigment dispersion containing a pigment, a pigment dispersant, a dispersion auxiliary resin, and a solvent, wherein the dispersion auxiliary resin is an epoxy resin represented by the following general formula (1), and other than the pigment in the pigment dispersion the weight ratio of the solid content of pigment min for (V) (P) (P / V ratio) is not less than 1.0, for preparing an ink jet ink by mixing at least a binder system with the pigment dispersion A pigment dispersion for an ink-jet ink used for a color filter, which is a preliminary preparation.
(However, R ¹ is a residue obtained by removing active hydrogen in an organic compound having k active hydrogens. N1, n2... Nk are each 0 or an integer of 1 to 100, and the sum is 1 to 1. And k is an integer of 1 to 100. A is an oxynorbornene skeleton having a substituent X or an oxycyclohexane skeleton having a substituent X, and is represented by the following formula:
  2. The pigment dispersion for inkjet ink used in a color filter according to claim 1, wherein the sum of n1 to nk in the epoxy resin represented by the general formula (1) is 4 to 30. 3.   3. The pigment dispersion for inkjet ink according to claim 1, wherein the dispersion auxiliary resin is 5 to 80 parts by weight with respect to 100 parts by weight of the pigment dispersant.   The solvent contains, as a main solvent, a solvent component having a boiling point of 180 ° C. to 260 ° C. and a vapor pressure at room temperature of 0.5 mmHg or less in a proportion of 50% by weight or more based on the total amount of the solvent, A pigment dispersion for inkjet ink used in the color filter according to claim 1.   The main solvent is ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol dibutyl ether, diethyl adipate, dibutyl oxalate, dimethyl malonate, diethyl malonate, dimethyl succinate, and diethyl succinate. The pigment dispersion for inkjet ink used for a color filter according to claim 4, wherein the pigment dispersion is one or more selected from the group consisting of: At least a pigment, a pigment dispersant, and an epoxy resin represented by the following general formula (1) contain at least a solvent component having a boiling point of 180 ° C. to 260 ° C. and a vapor pressure of 0.5 mmHg or less at room temperature as a main solvent. Mixing in a dispersion preparation solvent and dispersing to prepare a pigment dispersion;
(However, R ¹ is a residue obtained by removing active hydrogen in an organic compound having k active hydrogens. N1, n2... Nk are each 0 or an integer of 1 to 100, and the sum is 1 to 1. And k is an integer of 1 to 100. A is an oxynorbornene skeleton having a substituent X or an oxycyclohexane skeleton having a substituent X, and is represented by the following formula:
A method for producing an ink-jet ink for a color filter, comprising a step of adjusting the blending ratio of the main solvent in the total amount of the solvent to 60% by weight or more by any one of the following methods 1) to 3) .
1) The obtained pigment dispersion and at least the binder system are mixed with the newly prepared main solvent and / or auxiliary solvent.
2) At least a binder system is prepared by dissolving or dispersing in a newly prepared main solvent and / or auxiliary solvent to prepare a binder solution, and then the binder solution and the pigment dispersion are mixed.
3) At least a binder system is prepared by dissolving or dispersing in a newly prepared main solvent and / or auxiliary solvent to prepare a binder solution, and then the binder solution, the pigment dispersion, and the main solvent and / or auxiliary solvent are mixed. .