JP2009086285A - Color filter, manufacturing method thereof, and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a color filter superior in flatness of a color pixel part using ink superior in stability, a color filter manufactured by this method, and a display device including the color filter. <P>SOLUTION: The color filter manufacturing method includes: a first discharging step of forming the color pixel part by discharging ink to a recess surrounded with partitions formed on a substrate, by an ink jet system and using a first head to discharge ink A containing at least a coloring agent, an organic solvent, and curable compound, into the recess; and a second discharging step of using a second head other than the first head to discharge ink B containing at least a curable component into the recess to which the ink A has been discharged. The color filter is manufactured by this method. The display device is provided with the color filter. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a color filter, a manufacturing method thereof, and a display device including the color filter.

  In recent years, with the development of personal computers, particularly large-screen liquid crystal televisions, the demand for liquid crystal displays, especially color liquid crystal displays, has been increasing. However, since the 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 that the cost is high, 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 (colored pixel portion) by spraying colored ink by an inkjet method has been proposed (Patent Document 1). Here, when ink having good wettability with respect to the glass substrate is used, a method of printing a convex portion that is a boundary in advance with a substance with poor wettability with respect to the ink, or poor wettability with respect to the glass. In the case of using ink, a method is disclosed in which a pattern is formed in advance with a material having good wettability with ink, and the ink is fixed. However, controlling the glass substrate and the convex portion that forms the boundary to have ink affinity and ink repellency is effective in controlling color mixing between pixels and ink wettability, but the shape of the pixel portion itself is convex. There is a problem that the flatness of the colored pixel portion cannot be obtained due to the shape or the concave shape. In such a case, there arises a problem that the color density in the pixel varies and the display quality of the image is remarkably deteriorated.

  Patent Document 2 discloses a method for obtaining a flatness of a pixel portion by providing a flattening layer in the pixel portion. The above document describes a method of exposing from the substrate side, adjusting the degree of curing of the planarization layer according to the thickness of the pixel portion, and imparting flatness, but regarding variations in color density within the pixel portion, Nothing has been resolved. Patent Document 3 discloses a method of forming a film-like protective layer by transfer, but similarly, variations in color density in the pixel portion are not eliminated.

  Patent Document 4 discloses an ink having a color pigment and an extender pigment as an ink that imparts flatness to a pixel portion. In the above-mentioned document, the weight ratio between the resin and the pigment, the weight ratio between the colored pigment and the extender pigment, and the solid content in the ink are also mentioned. However, when the present inventors made an additional examination of the above document, it was found that sufficient flatness could not be obtained. Patent Document 5 discloses a method of imparting flatness while adjusting the density in the pixel portion using dark and light inks. However, the process becomes complicated and sufficient flatness cannot be obtained.

  Moreover, a method for obtaining flatness by controlling the dry state of the pixel portion is disclosed (Patent Documents 6, 7, and 8). Patent Document 6 describes that the flatness of the pixel portion can be obtained by exposing the ink before drying. Patent Document 7 describes a method of drying at a higher temperature as the viscosity of the ink is higher. Furthermore, Patent Document 8 describes a method of adjusting the drying condition according to the shape of the pixel. However, the methods of Patent Documents 6 and 7 do not provide sufficient flatness, and the method of Patent Document 8 is impractical when considering actual production.

  Further, Patent Documents 9 and 10 disclose a color filter in which the end of the pixel portion has a thickness of 80% or more of the highest portion, but does not disclose any means for obtaining flatness.

Furthermore, Patent Document 11 discloses a method of repeating ink ejection and drying many times in order to prevent ink from overflowing from a recess surrounded by a partition wall and mixing with other pixels. Although the above method can prevent color mixing in the pixel portion and at the same time improve the flatness of the pixel portion, the process becomes complicated and is not suitable for actual manufacturing.
JP 59-75205 A JP-A-8-304619 JP-A-10-197719 JP-A-9-132740 JP 2004-177867 A Japanese Patent Laid-Open No. 11-142641 JP 2002-372613 A JP 2003-266003 A JP 2002-148429 A JP 2002-156520 A JP 2004-325736 A

  The present invention has been made in view of the above-described conventional problems, and includes a color filter manufacturing method excellent in ink stability and color pixel portion flatness, a color filter manufactured by the method, and the color filter. An object is to provide a display device.

That is, the present invention
<1> A method for producing a color filter, wherein a colored pixel portion is formed by ejecting ink to a recess surrounded by a partition formed on a substrate by an ink jet method.
A first ejection step of ejecting ink A including at least a colorant, an organic solvent, and a component that is polymerized and cured by light and / or heat using the first head into the recess; and the first head A second ink that discharges ink B including at least a component that initiates and / or accelerates curing of a component that is polymerized and cured by light and / or heat using a different second head to the recessed portion where the ink A is discharged. A color filter manufacturing method comprising: a discharge step.

  <2> The method for producing a color filter according to <1>, wherein at least one of the components that are polymerized and cured by light and / or heat is an epoxy compound.

  <3> The method for producing a color filter according to <1> or <2>, wherein the component that initiates and / or accelerates the curing is an acidic substance.

  <4> The method for producing a color filter according to <1> or <2>, wherein the component that initiates and / or accelerates the curing is a substance that generates an acid by light and / or heat. .

  <5> A drying process for removing the organic solvent contained in the ink A is provided between the first ejection process and the second ejection process, and the drying process is polymerized by the light and / or heat. The method for producing a color filter according to any one of <1> to <4>, wherein the method is performed under a condition in which a component to be cured is not polymerized.

  <6> 85% by mass or more of the organic solvent contained in the ink A is composed of a compound having a boiling point at normal pressure of 180 ° C. to 280 ° C. and a vapor pressure at room temperature of 0.5 mmHg or less. <1> to <5>. The method for producing a color filter according to any one of <1> to <5>.

  <7> The method for producing a color filter according to any one of <1> to <6>, wherein the colorant is an organic pigment.

  <8> The method for producing a color filter according to <7>, wherein the number average particle diameter of the organic pigment is 100 nm or less.

  <9> The method for producing a color filter according to any one of <1> to <8>, wherein the ink A further contains a surfactant.

  <10> The method for producing a color filter according to any one of <1> to <9>, wherein the viscosity of the ink A at 25 ° C. is 5 mPa · s to 30 mPa · s. .

  <11> In the first discharge step, at least the red ink A, the green ink A, and the blue ink A are each discharged into a predetermined recess. It is a manufacturing method of the color filter as described in any one.

  <12> In the first ejection step, at least two types of ink A are each ejected to a predetermined recess, and then the drying step is performed. Thereafter, in the second ejection step, the ink B is placed in the recess in which the ink A is ejected. The method for producing a color filter according to any one of <5> to <11>, wherein the color filter is discharged.

  <13> After the second ejection step, the method includes a curing step of curing a component that is polymerized and cured by light and / or heat by light irradiation and / or heating. <1> to <12> The method for producing a color filter according to any one of the above.

  <14> The method for producing a color filter according to <13>, wherein the heating temperature in the curing step is 200 ° C. or higher.

  <15> A color filter manufactured by the method for manufacturing a color filter according to any one of <1> to <14>.

  <16> A display device comprising the color filter according to <15>.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the color filter excellent in the stability of an ink and the flatness of a coloring pixel part, the color filter manufactured by the method, and a display apparatus provided with this color filter are provided.

  Hereinafter, the color filter, the manufacturing method thereof, and the display device of the present invention will be described in detail.

<Color filter and manufacturing method thereof>
The color filter manufacturing method of the present invention is a color filter manufacturing method in which a colored pixel portion is formed by ejecting ink to a recess surrounded by a partition formed on a substrate by an ink jet method. First discharge step of discharging ink A containing at least a colorant, an organic solvent, and a component that is polymerized and cured by light and / or heat (hereinafter sometimes referred to as a curable compound) into the concave portion. And an ink B containing at least a component that initiates and / or accelerates the curing of the curable compound using a second head different from the first head (hereinafter sometimes referred to as a curing component). And a second ejection step for ejecting the ink A into the recessed portion from which the ink A has been ejected.

  According to the method for producing a color filter of the present invention, a color filter having a colored pixel portion having excellent flatness can be obtained. In addition, since the ink used in the method for producing a color filter of the present invention has a two-component configuration of ink A containing a curable compound and ink B containing a curable component, the stability of the ink (particularly, viscosity stability over time). ).

  First, the physical properties of inks (ink A and ink B) used in the method for producing a color filter of the present invention and each component contained in the ink will be described in detail.

The viscosity of the ink A according to the present invention at 25 ° C. is preferably 5 mPa · s or more and 30 mPa · s or less, and preferably 7 mPa · s or more and 25 mPa from the viewpoint of securing the dischargeability from the head (hereinafter sometimes referred to as an inkjet head). -S or less is still more preferable. The preferred viscosity range of ink B is the same as that of ink A.
The surface tension of the ink according to the present invention (ink A and ink B) is preferably 10 to 50 dyne / cm at 25 ° C., more preferably 20 to 40 dyne / cm.

(Coloring agent)
Ink A according to the present invention contains a colorant. Ink B may contain a colorant as necessary.
As the pigment as the colorant, any one of organic colorants and inorganic colorants can be selected and used in accordance with the desired color such as R, G, and B of the pixel (colored pixel 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.

  The number average particle diameter of the organic pigment used in the present invention is preferably 100 nm or less from the viewpoint of contrast and ink ejection properties, more preferably 80 nm or less, and particularly preferably 60 nm or less.

  Examples of the organic pigment include compounds classified as pigments in the Color Index (CI; issued by The Society of Dyers and Colorists), specifically, the following color index (C.I. .) Can be listed with numbers.

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

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

C. I. Pigment red 1, C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 4, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 8, C.I. I. Pigment red 9, C.I. I. Pigment red 10, C.I. I. Pigment red 11, C.I. I. Pigment red 12, C.I. I. Pigment red 14, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 17, C.I. I. Pigment red 18, C.I. I. Pigment red 19, C.I. I. Pigment red 21, C.I. I. Pigment red 22, C.I. I. Pigment red 23, C.I. I. Pigment red 30, C.I. I. Pigment red 31, C.I. I. Pigment red 32, C.I. I. Pigment red 37, C.I. I. Pigment red 38, C.I. I. Pigment red 40, C.I. I. Pigment red 41, C.I. I. Pigment red 42, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 48: 2, C.I. I. Pigment red 48: 3, C.I. I. Pigment red 48: 4, C.I. I. Pigment red 49: 1, C.I. I. Pigment red 49: 2, C.I. I. Pigment red 50: 1, C.I. I. Pigment red 52: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 57: 2, C.I. I. Pigment red 58: 2, C.I. I. Pigment red 58: 4, C.I. I. Pigment red 60: 1, C.I. I. Pigment red 63: 1, C.I. I. Pigment red 63: 2, C.I. I. Pigment red 64: 1, C.I. I. Pigment red 81: 1, C.I. I. Pigment red 83, C.I. I. Pigment red 88, C.I. I. Pigment red 90: 1, C.I. I. Pigment red 97, C.I. I. Pigment red 101, C.I. I. Pigment red 102, C.I. I. Pigment red 104, C.I. I. Pigment red 105, C.I. I. Pigment red 106, C.I. I. Pigment red 108, C.I. I. Pigment red 112, C.I. I. Pigment red 113, C.I. I. Pigment red 114, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 144, C.I. I. Pigment red 146, C.I. I. Pigment red 149, C.I. I. Pigment red 150, C.I. I. Pigment red 151, C.I. I. Pigment red 166, C.I. I. Pigment red 168, C.I. I. Pigment red 170, C.I. I. Pigment red 171, C.I. I. Pigment red 172, C.I. I. Pigment red 174, C.I. I. Pigment red 175, C.I. I. Pigment red 176, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. Pigment red 179, C.I. I. Pigment red 180, C.I. I. Pigment red 185, C.I. I. Pigment red 187, C.I. I. Pigment red 188, C.I. I. Pigment red 190, C.I. I. Pigment red 193, C.I. I. Pigment red 194, C.I. I. Pigment red 202, C.I. I. Pigment red 206, C.I. I. Pigment red 207, C.I. I. Pigment red 208, C.I. I. Pigment red 209, C.I. I. Pigment red 215, C.I. I. Pigment red 216, C.I. I. Pigment red 220, C.I. I. Pigment red 224, C.I. I. Pigment red 226, C.I. I. Pigment red 242, C.I. I. Pigment red 243, C.I. I. Pigment red 245, C.I. I. Pigment red 254, C.I. I. Pigment red 255, C.I. I. Pigment red 264, C.I. I. Pigment red 265;

C. I. Pigment blue 15, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 15: 4, C.I. I. Pigment blue 15: 6, C.I. I. Pigment blue 60; I. Pigment green 7, C.I. I. Pigment green 36; C.I. I. Pigment brown 23, C.I. I. Pigment brown 25; C.I. I. Pigment Black 1 and 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.

  In order to form the colored pixel portion, the colorant is usually blended at a ratio of 1 to 60% by mass, preferably 15 to 40% by mass with respect to the total solid content of the ink A. If the amount of the colorant is too small, the transmission density when the ink is ejected to a predetermined film thickness (usually 0.1 to 2.0 μm) may not be sufficient. Also, if there is too much colorant, the properties as a coating film such as adhesion to the substrate when the ink is ejected onto the substrate and cured, surface roughness of the cured film, and coating film hardness may be insufficient. There is.

(Pigment dispersant)
In the case of using a pigment as the colorant, a pigment dispersant is blended in the ink A (and the ink B when the pigment is included) as necessary in order 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.

(Organic solvent)
The organic solvent contained in the ink A according to the present invention is not particularly limited, but 85% by mass or more (more preferably 90% by mass or more) of the organic solvent contained in the ink A is normal pressure (760 mmHg). Has a boiling point of 180 ° C. to 280 ° C. (more preferably 210 ° C. to 270 ° C.) and a vapor pressure at room temperature (especially in the range of 18 ° C. to 25 ° C.) of 0.5 mmHg or less (more preferably 0.1 mmHg or less). It is preferably composed of a compound (hereinafter sometimes referred to as a main solvent).

A main solvent having a boiling point of 180 ° C. to 280 ° C. at normal pressure (760 mmHg) and a vapor pressure of 0.5 mmHg or less at normal temperature has appropriate drying and evaporating properties. For this reason, the ink A according to the present invention containing such a main solvent at a high blending ratio does not dry rapidly when performing either intermittent ejection or continuous ejection, and therefore has a rapid viscosity at the nozzle tip of the inkjet head. It is difficult to raise and clog, hardly wet the orifice surface, and has excellent discharge direction and discharge amount stability. Therefore, the colored pixel portion can be accurately and uniformly formed by ejecting the ink by the inkjet method into the concave portion surrounded by the partition formed on the substrate.
Furthermore, the ink A according to the present invention does not dry rapidly at the nozzle tip of the inkjet head, but has an appropriate drying property. Therefore, after being discharged onto the substrate, the substrate can be sufficiently leveled by being familiar with the substrate surface, and then can be completely dried in a relatively short time by natural drying or a general heating method. Therefore, according to the present invention, a highly uniform colored pixel portion can be obtained and dried efficiently.

  When the ink A according to the present invention uses a pigment as a colorant, the pigment is mixed with a dispersant in advance in a part of the total amount of organic solvent to impart dispersibility, and the resulting pigment dispersion (ie, In many cases, a high-concentration pigment dispersion) is introduced into the remaining organic solvent together with other blending components and mixed to obtain an ink. In order to prepare a pigment dispersion, it is easy to disperse the pigment, such as 1,3-butylene glycol diacetate (1,3-BGDA), dipropylene glycol monomethyl ether acetate (DPMA), and diethylene glycol monobutyl ether acetate. In addition, it is preferable to use a solvent having a boiling point of 180 ° C. to 280 ° C. at normal pressure (760 mmHg) and a vapor pressure of 0.5 mmHg or less at room temperature.

The ink A may contain a small amount of a solvent component other than the main solvent, if necessary, like a dispersion solvent used for preparing a pigment dispersion. 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 85% by mass or more based on the total amount of the organic solvent. When the ratio of the main solvent is less than 85% by mass of the total amount of the solvent, there may be cases where it is impossible to reliably obtain drying properties and evaporation properties suitable for the ink jet method.
It is desirable to use the main solvent at a blending ratio as high as possible, specifically 85 mass% or more, preferably 90 mass% or more of the total amount of the organic solvent. Therefore, it is preferable to use the main solvent as a dispersion solvent by appropriately selecting the main solvent by mixing with the dispersion solvent when preparing the pigment dispersion.

  The main solvent can be selected from the following compounds: glycol ethers such as ethylene glycol monoethyl ether; glycol ether esters such as ethylene glycol monomethyl ether acetate; diethylene glycol monomethyl ether and the like. Glycol oligomer ethers; glycol oligomer ether esters such as diethylene glycol monomethyl ether acetate; glycol monoesters such as 1,3-butylene glycol monoacetate; glycol diesters such as 1,3-butylene glycol diacetate; Aliphatic carboxylic acids such as acetic acid, 2-ethylhexanoic acid and acetic anhydride or their anhydrides; aliphatic or aromatic such as ethyl acetate and propyl benzoate Stealtes; Dicarboxylic acid diesters such as diethyl carbonate; Alkoxycarboxylic acid esters such as methyl 3-methoxypropionate; Ketocarboxylic acid esters such as ethyl acetoacetate; Halogenated carboxyls such as chloroacetic acid and dichloroacetic acid Acids; alcohols or phenols such as ethanol, isopropanol and phenol; aliphatic or aromatic ethers such as diethyl ether and anisole; alkoxy alcohols such as 2-ethoxyethanol and 1-methoxy-2-propanol; Glycol oligomers such as diethylene glycol and tripropylene glycol; amino alcohols such as 2-diethylaminoethanol and triethanolamine; alkoxy alcohols such as 2-ethoxyethyl acetate Call esters; ketones such as acetone, methyl isobutyl ketone; N- ethylmorpholine, morpholines such as phenyl morpholine; pentylamine, tripentylamine, aliphatic or aromatic amines such as aniline.

  Specific examples of compounds that can be used as the main solvent include ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol dibutyl ether, dipropylene glycol monomethyl ether acetate, dipropylene glycol monopropyl ether acetate, and tripropylene. Glycol monobutyl ether, 1,3-butylene glycol monoacetate, 1,3-butylene glycol diacetate, 1,6-hexaethylene glycol diacetate, diethyl adipate, dibutyl oxalate, dimethyl malonate, diethyl malonate, succinic acid Examples thereof include dimethyl and diethyl succinate. These solvents not only satisfy the requirements of a boiling point of 180 ° C. to 280 ° C. and a vapor pressure at room temperature of 0.5 mmHg or less, and also have relatively good dispersibility and dispersion stability of pigments. -A pigment dispersion can be prepared by mixing with a solvent conventionally used for preparing a pigment dispersion, such as methoxybutyl acetate or propylene glycol monomethyl ether acetate (PGMEA), or without using it as a dispersion solvent. it can.

  Specific examples of the organic solvent contained in the ink B according to the present invention are the same as the specific examples related to the ink A described above.

(Curable compound)
Ink A according to the present invention contains a curable compound. The curable compound functions as a binder component in the ink A, and may be a photocurable binder component or a thermosetting binder component. Further, if necessary, a polymer having no polymerization reactivity can be used in combination. Ink B according to the present invention contains a curable component to be described later. Therefore, it is preferable not to add a curable compound to ink B from the viewpoint of storage stability.
Hereinafter, a photocurable binder component, a thermosetting binder component, and a polymer which is used as necessary and has no polymerization reactivity will be described.

(1) Photo-curable binder component For the binder component containing a photo-curable resin that can be polymerized and cured by light such as ultraviolet rays and electron beams, it is intended to provide film formability and adhesion to the coated surface. 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 the 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 two or more types may be used in combination. May be. And, a polyfunctional monomer or oligomer having a polymer having a relatively high molecular weight as a main component and having two or more photopolymerizable functional groups as needed, a monofunctional monomer or oligomer having one photopolymerizable functional group, etc. To form a photocurable binder component.

  When a polymer with no polymerization reactivity is used as a polymer having a relatively high molecular weight, the binder component is a polyfunctional monomer or oligomer having two or more photopolymerizable functional groups. Blend ingredients. In this case, in the binder system, the polyfunctional polymerizable component is polymerized spontaneously by light irradiation or polymerized by the action of a curing component described later such as a photopolymerization initiator activated by light irradiation. Thus, a network structure is formed, and a component such as a resin or a pigment having no polymerization reactivity is wrapped in the network structure and cured.

As such a polymer having no polymerization reactivity, for example, a copolymer comprising two or more of the following monomers can be used: acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, 2-hydroxyethyl acrylate. 2-hydroxyethyl methacrylate, benzyl acrylate, benzyl methacrylate, styrene, polystyrene macromonomer, and polymethyl methacrylate 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. A polymer having no polymerization reactivity in itself may be blended in the ink B according to the present invention.

The polymer itself having polymerization reactivity is an oligomer obtained by introducing a polymerizable functional group into a non-polymerizable binder molecule or a polymer having a higher molecular weight than an oligomer, and is itself exposed to light irradiation. May cause a polymerization reaction, or may induce a polymerization reaction by the action of a curing component described later, such as a photopolymerization initiator activated by light irradiation.
Various ethylenic double bond-containing compounds themselves have polymerization reactivity and can be used as photocurable resins. Conventionally, a prepolymer blended in a UV curable resin composition 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.

The molecular weight of the ethylenic double bond-containing compound used as a polymer having polymerization reactivity per se is so that the viscosity of the ink according to the present invention is not too high to adversely affect the discharge performance from the discharge head. The average molecular weight is preferably 25,000 or less.
The polymer having a relatively high molecular weight is usually blended at a ratio of 1 to 50% by mass with respect to the total solid content of the ink. Here, the solid content of the ink for specifying the blending ratio includes all components except the solvent, and liquid polymerizable monomers and the like are also included in the solid content.

Even in the case of using a polymer having polymerization reactivity, in order to improve the strength of the colored pixel portion and the adhesion to the substrate, a polyfunctional polymerizable component such as a polyfunctional monomer or oligomer is blended. Is preferred. 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 that forms a network structure, a bifunctional or higher functional monomer or oligomer can be used. In order to impart sufficient strength and adhesion to the colored pixel portion, a tetrafunctional or higher functional monomer or oligomer is usually used for the photocurable resin.

  However, since the ink according to the present invention is used as an ink jet ink, a polymerizable component other than a 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, and it is particularly preferable to use a bi- or trifunctional monomer having a viscosity of 100 mPa · s 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.

The blending ratio of the bifunctional to trifunctional monomer is usually 20 to 70% by mass with respect to the total solid content of the ink.
Here, when the blending ratio of the bifunctional to trifunctional monomer is less than 20% by mass of the total solid content, the ink is not sufficiently diluted with the monomer, and the viscosity of the ink is high from the beginning or after the solvent component is volatilized. There is a risk of clogging the nozzles of the inkjet head. Further, when the blending ratio of the bi- to trifunctional monomer exceeds 70% by mass of the total solid content, the crosslinking density is lowered, the solvent resistance, adhesion, and hardness of the colored pixel portion are inferior, and sufficient characteristics are obtained. There is a risk that it will not be obtained.

However, when all the polyfunctional monomers blended in the ink are di- or tri-functional monomers, viscosity increase due to drying of the ink is unlikely to occur, so that the ejection performance of the inkjet head is stabilized. In some cases, the film strength of the pixel portion, adhesion to the substrate, solvent resistance, and the like are insufficient. 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 strength and adhesion can be imparted to the colored pixel portion.
Examples of tetrafunctional monomers and oligomers include pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, and the like.

The tetrafunctional or higher polyfunctional component is usually blended at a ratio of 1 to 30% by mass with respect to the total solid content of the ink. Further, in order to balance the ejection stability with the bi- or tri-functional monomer and the improvement in strength and adhesion due to the polyfunctional component having four or more functional groups, the tetrafunctional group is used with respect to 100 parts by mass of the bi- to trifunctional monomers. The blending ratio of the above polyfunctional components is usually 1 to 50 parts by mass, preferably the lower limit of the blending ratio is 2 parts by mass and / or the upper limit of the blending ratio is 35 parts by mass or less.
Here, if the blending ratio of the tetrafunctional or higher polyfunctional component is less than 1 part by mass with respect to 100 parts by mass of the bi- to tri-functional monomer, the hardness and solvent resistance after curing the ink There is a possibility that the characteristics such as are not sufficiently obtained. Moreover, when the said mixture ratio of the polyfunctional component more than tetrafunctional exceeds 50 mass parts, there exists a possibility that the hardening rate of an ink may become slow and process speed may become slow.

Moreover, you may mix | blend a monofunctional monomer and an oligomer with a photocurable binder component as needed.
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.

(2) Thermosetting binder component As the thermosetting binder, a compound having two or more thermosetting functional groups in one molecule is usually used. An epoxy group is preferably used as the thermosetting functional group. In addition, a polymer having no polymerization reactivity may be used in combination.
As a compound having two or more thermosetting functional groups in one molecule, an epoxy compound having two or more epoxy groups in one molecule is usually 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 colored pixel portion, a polymer having a relatively high molecular weight and the crosslink density of the colored pixel portion are increased, or the ink jet discharge performance is reduced by lowering the viscosity of the ink. In order to improve this, it is preferable to use a compound having a relatively low molecular weight.

  The epoxy compound which is a polymer having a relatively high molecular weight (hereinafter sometimes referred to as “binder epoxy compound”) is represented by at least the structural unit represented by the following formula (1) and the following formula (2). A polymer composed of structural units and having two or more glycidyl groups can be used.

(R ¹ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ² is a hydrocarbon group having 1 to 12 carbon atoms.)

(R ³ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.)
The structural unit represented by the formula (1) is derived from a monomer represented by the following formula (3).

(R ¹ and R ² are the same as in formula (1).)

By using the monomer represented by the formula (3) as a constituent unit of the binder epoxy compound, sufficient hardness and transparency can be imparted to the colored pixel portion. In the formula (3), R ² is a hydrocarbon group having 1 to 12 carbon atoms, and may be any of a linear aliphatic, alicyclic, and aromatic hydrocarbon group, and 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, and the like.

Specific examples of the monomer represented by the formula (3) 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 present invention, (meth) acrylate means either acrylate or methacrylate, and (meth) acryloyl means either acryloyl or methacryloyl.

In the formula (3), hydrogen or a methyl group is preferable as R ¹ , and an alkyl group having 1 to 12 carbon atoms is preferable as R ² , and a methyl group and a cyclohexyl group are particularly preferable among them. Preferable examples of the monomer represented by the above formula (3) include methyl methacrylate (MMA) and cyclohexyl methacrylate (CHMA).

  The structural unit represented by the formula (2) in the polymer is derived from a monomer represented by the following formula (4).

(R ³ is the same as in formula (2).)

The monomer represented by the formula (4) is used for introducing an epoxy group (epoxy reaction point) into the polymer. Ink A containing the polymer is excellent in storage stability, and hardly increases in viscosity during storage and discharge operations. One of the reasons is the epoxy group in formula (2) or formula (4). Is presumed to be because of glycidyl group. If alicyclic epoxy acrylate is used instead of the monomer represented by formula (4), the viscosity of ink A tends to increase.
In the formula (4), R ³ is preferably hydrogen or a methyl group. Specific examples of the monomer represented by the formula (4) 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 (1) or the formula (2) 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 formula (1) and the structural unit of formula (2) in the binder epoxy compound is derived from the monomer that derives the structural unit of formula (1) and the structural unit of formula (2). The weight ratio with the monomer to be charged (monomer that derives formula (1): monomer that derives formula (2)) is in the range of 10:90 to 90:10. preferable.
When the amount of the structural unit of the formula (1) is more than the above ratio of 10:90, there is a possibility that the reaction point of curing decreases and the crosslinking density is lowered, whereas the structural unit of the formula (2) 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 colored pixel portion are likely to be insufficient. In addition, since the ink according to the present invention is used in an ink jet system, the binder epoxy compound preferably has a weight average molecular weight of 20,000 or less, more preferably 15,000 or less when expressed in terms of polystyrene equivalent weight average molecular weight. It is particularly preferred that If the molecular weight is more than 20,000, the viscosity is likely to increase, the stability of the ejection amount when ejected from the ejection head and the straightness in the ejection direction may be degraded, and the stability of long-term storage is degraded. Because there is a fear.

  As the binder epoxy compound, it is particularly preferable to use a glycidyl methacrylate (GMA) / methyl methacrylate (MMA) copolymer having a polystyrene-reduced weight average molecular weight (Mw) in the above range. The GMA / MMA copolymer may contain other monomer components as long as the object of the present invention can be achieved.

As a synthesis example of the binder epoxy compound, for example, a solvent containing no hydroxyl group is charged into a four-necked flask equipped with a thermometer, a reflux condenser, a stirrer, and a dropping funnel, and the temperature is raised to 120 ° 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 (3), the monomer represented by the above formula (4), 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 120 ° 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 kept for 2 hours, whereby the binder epoxy compound is obtained.
The thermosetting binder component used in the present invention is an epoxy compound having two or more epoxy groups in one molecule, and has a molecular weight smaller than that of the binder epoxy compound (hereinafter referred to as “polyfunctional epoxy compound”). It is preferable to add. The polystyrene-reduced weight average molecular weight of the polyfunctional epoxy compound is preferably 4,000 or less, particularly preferably 3,000 or less, on condition that it is smaller than the binder epoxy compound combined therewith.

  In addition, the polystyrene conversion weight average molecular weight of an epoxy compound can be calculated | required by GPC (gel permeation chromatography), As a measurement condition, tetrahydrofuran is used as a developing solution, for example, HLC-8029 (made by Tosoh Corporation) is used. Can be measured.

  Since the epoxy group (glycidyl group) is introduced into the binder epoxy compound by the structural unit represented by the formula (2), there is a limit to the amount of epoxy that can be introduced into the molecule of the copolymer. When a polyfunctional epoxy compound having a relatively small molecular weight is added to the ink A, the concentration of the reactive sites of the epoxy increases, 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. When the weight-average molecular weight of the binder epoxy compound is 10,000 or less in order to improve the discharge performance from the inkjet discharge head, the strength and hardness of the colored pixel portion are likely to decrease. It is preferable to add a tetrafunctional or higher polyfunctional epoxy compound to the ink A 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 resins, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, glyoxal type epoxy resins, alicyclic epoxy resins, and the like heterocyclic epoxy resin.

More specifically, bisphenol A type epoxy resins such as trade name Epicoat 828 (manufactured by Yuka Shell Epoxy), bisphenol F type epoxy resins such as trade name YDF-175S (manufactured by Tohto Kasei Co., Ltd.), trade name YDB-715 Brominated bisphenol A type epoxy resins (made by Toto Kasei Co., Ltd.), bisphenol S type epoxy resins such as trade name EPICLON EXA1514 (Dainippon Ink Chemical Co., Ltd.), trade name YDC-1312 (made by Toto Kasei Co., Ltd.), etc. Hydroquinone type epoxy resin, Naphthalene type epoxy resin such as trade name EPICLON EXA4032 (manufactured by Dainippon Ink & Chemicals), Biphenyl type epoxy resin such as trade name Epicoat YX4000H (manufactured by Yuka Shell Epoxy), Trade name Epicoat 157S70 (oil) Shell Epoxy ) Phenol novolac epoxy resin such as bisphenol A type epoxy resin, trade name Epicoat 154 (manufactured by Yuka Shell Epoxy), trade name YDPN-638 (manufactured by Tohto Kasei Co., Ltd.), trade name YDCN-701 Cresol novolac type epoxy resin such as Kasei Co., Ltd., dicyclopentadiene phenol type epoxy resin such as EPICLON HP-7200 (produced by Dainippon Ink and Chemicals), Epicoat 1032H60 (produced by Yuka Shell Epoxy), etc. Trishydroxyphenylmethane type epoxy resin, trifunctional epoxy resin such as trade name VG3101M80 (manufactured by Mitsui Chemicals), tetraphenylolethane type epoxy resin such as trade name Epicoat 1031S (manufactured by Yuka Shell Epoxy), trade name Denako Tetrafunctional epoxy resin such as EX-411 (manufactured by Nagase Kasei Kogyo Co., Ltd.), hydrogenated bisphenol A type epoxy resin such as trade name ST-3000 (manufactured by Toto Kasei Co., Ltd.), trade name Epicoat 190P (manufactured by Yuka Shell Epoxy Co., Ltd.) ), Glycidyl ester type epoxy resins such as trade name YH-434 (manufactured by Toto Kasei Co., Ltd.), glyoxal type epoxy resins such as trade name YDG-414 (manufactured by Tohto Kasei Co., Ltd.), and brand name Epolide GT Examples include alicyclic polyfunctional epoxy compounds such as -401 (manufactured by Daicel Chemical Industries), and heterocyclic epoxy resins such as triglycidyl isocyanate (TGIC). 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 Epicoat 157S70 (manufactured by Yuka Shell Epoxy) and cresol novolak type epoxy such as trade name YDCN-701 (manufactured by Tohto Kasei) Resins are particularly preferred.

(Curing component)
The ink B according to the present invention includes a curing component that polymerizes and cures the curable compound contained in the ink A. When the curable compound contained in ink A is a photocurable binder component, a photopolymerization initiator is blended in ink B as a curable component. Further, when the curable compound contained in the ink A is a thermosetting binder component, the ink B is mixed with a curing agent as a curable component. In addition, since the curable compound mentioned above is mix | blended with the ink A which concerns on this invention, it is preferable not to mix | blend a hardening component with the ink A from a viewpoint of storage stability.

  When the curable compound contained in the ink A is a photocurable binder component, the ink B is blended with a photopolymerization initiator having activity with respect to the wavelength of the light source used as the curing component. The photopolymerization initiator is appropriately selected in consideration of the difference in the reaction format of the binder and the polyfunctional monomer (for example, radical polymerization and 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-morpholinopropan-1-one, 2-benzyl-2-dimethyl Amino-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, bisacylphospho Fin 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- Dimethylaminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid isoamyl ester, 1,3,5-triacroylhexahydro-s-triazine, 2- [2- (5-methylfuran-2-yl) ethenyl]- 4,6-bis (tri Rolomethyl) -s-triazine, 2- [2- (furan-2-yl) ethenyl] -4,6-bis (trichloromethyl) -s-triazine, methylbenzoylformate, 2,4,6-trimethylbenzoyldiphenyl A photopolymerization initiator such as phosphine oxide can be used.

When the curable compound contained in ink A is a thermosetting binder component, a curing agent is blended in ink B as a curable component. As the curing agent, for example, an acidic substance such as a polyvalent carboxylic acid anhydride or a polyvalent carboxylic acid is used.
Specific examples of polyhydric carboxylic acid anhydrides 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 polyvalent carboxylic acid anhydrides and polyvalent carboxylic acids can be used singly or in combination of two or more.

  Further, in order to improve the hardness and heat resistance of the colored pixel portion, the ink B may be added with a catalyst that can promote the thermosetting reaction between the acid and the epoxy. 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 [RNR ′] ⁺ X ⁻ , a sulfonium compound [RSR ′] ⁺ X ⁻ , an oxonium compound [ROR ′] ⁺ X ^{−, and the} like. Here, R and R ′ are alkyl, alkenyl, aryl, alkoxy and the like.

  When the curable compound contained in the ink A is an epoxy compound, the ink B includes a photoacid generator that is a substance that generates acid by light as a curing component and a thermal acid generator that is a substance that generates acid by heat. It can also be blended. The photoacid generator is not particularly limited as long as it generates an acidic substance upon irradiation with ultraviolet rays. Specific examples thereof include compounds described in [0052] to [0060] of JP-A-2007-191567. Etc. The thermal acid generator is not particularly limited as long as it generates an acidic substance by heating. Specific examples thereof include blocks described in [0025] to [0038] of JP-A No. 2004-355933, for example. And latent carboxyl group-generating compounds such as trimellitic acid.

  There is no particular limitation on the amount of the curable component to be blended in the ink B. In the range of an appropriate discharge amount, the amount of the curable component is set to an amount that is sufficient for the curable compound to be set to 0. 01-20 mass% is preferable, 0.1-10 mass% is still more preferable, and 1-5 mass% is especially preferable.

(Surfactant)
In the ink A according to the present invention, a surfactant may be blended for the purpose of improving the wettability of the ink with respect to the pixel surface. As examples of the surfactant, the surfactants disclosed in JP-A-7-216276, paragraph [0021], JP-A-2003-337424, and JP-A-11-133600 are preferable. As mentioned. The content of the surfactant is preferably 5% by mass or less based on the total amount of the ink A.
A surfactant may be added to the ink B as necessary, and specific examples and preferred contents thereof are the same as those of the ink A.

(Other ingredients)
Ink A and ink B according to the present invention may contain one or more other additives as required. 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 and the like.
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) Dispersing aid: For example, blue pigment derivatives such as copper phthalocyanine derivatives, yellow pigment derivatives, and the like.

e) Filler: For example, glass, alumina and the like.
f) Adhesion promoter: for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane.
g) Antioxidant: For example, 2,2-thiobis (4-methyl-6-t-butylphenol), 2,6-di-t-butylphenol and the like.
h) Ultraviolet absorber: For example, 2- (3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, alkoxybenzophenone and the like.
i) Anti-aggregation agent: for example, sodium polyacrylate or various surfactants.

In the color filter manufacturing method of the present invention, in the first ejection step, the above-described ink A is ejected into the recess surrounded by the partition formed on the substrate using the first head. Next, in the second ejection step, the above-described ink B is ejected into the concave portion where the ink A is ejected using a second head different from the first head. By separating the head that ejects ink A (first head) and the head that ejects ink B (second head), clogging of the head can be prevented.
The partition walls are formed on the substrate in advance before ink ejection, and details of the method for forming the partition walls will be described later.

  The relationship between the discharge amount of ink A in the first discharge step and the discharge amount of ink B in the second discharge step is the kind and amount of the curable compound contained in ink A and the kind of curable component contained in ink B and It is determined appropriately based on the amount. For example, the ink A and the ink B are preferably ejected so that the curing component is in the range of 1 to 100 parts by mass per 100 parts by mass of the curable compound, and more preferably 5 to 80 parts by mass. When the curing component is less than 1 part by mass, curing may be insufficient and a tough colored pixel portion may not be formed. Moreover, when a hardening component exceeds 100 mass parts, the adhesiveness with respect to the board | substrate of a colored pixel part will be inferior, and a uniform and smooth colored pixel part cannot be formed.

  The color filter according to the present invention is preferably in the form of a group composed of colored pixel portions of three colors by discharging ink of three colors of RGB. In the first ejection step, at least a red ink, a green ink A, and a blue ink A are each ejected into a predetermined recess, thereby forming a color composed of a group of three colored pixel portions. A filter can be obtained.

In the color filter manufacturing method of the present invention, it is preferable to have a drying step of removing the organic solvent contained in the ink A between the first discharge step and the second discharge step. The drying step is performed under conditions that do not polymerize the curable compound contained in ink A.
Since the drying step is performed under a condition in which the curable compound is not polymerized, an increase in the viscosity of the ink A due to the polymerization of the curable compound can be suppressed during the drying step. Therefore, the shape of the ink A discharged in the concave portion after the drying step has a flat surface, and as a result, the flatness of the colored pixel portion can be further improved. Usually, when the viscosity of the ink A is high during drying, it is difficult to flatten the shape of the ink A after drying.
In addition, since the ink B containing a curable component is applied to the ink A after the drying step, the viscosity of the ink A due to the reaction between the curable compound and the curable component does not occur in the drying step, and the colored pixel portion The flatness of can be further improved.

Whether or not the drying process is “conditions for not polymerizing the curable compound” is determined by whether or not the polymerization of the ink A is started and gelation of the ink A is observed. Specifically, when the ink is processed under the pixel drying conditions in a state where the solvent does not evaporate, the increase in the viscosity of the ink A after the processing is less than 5 mPa · s with respect to the viscosity of the ink A before the processing. Is determined as “conditions for not polymerizing the curable compound”.
The conditions for the drying step in the present invention are not particularly limited as long as they are the above-mentioned “conditions for not polymerizing the curable compound”, but the drying step is preferably performed by heating or drying under reduced pressure. The drying temperature in this case is not particularly limited as long as the solvent in the ink A discharged to the pixel evaporates and the curable compound in the ink A does not start thermal polymerization, but the solvent is efficiently used. In evaporating, 60 to 120 ° C is preferable, and 80 to 100 ° C is more preferable. In addition, it is preferable to perform the drying step under reduced pressure because the drying step can be performed at a lower temperature. The drying temperature in this case is preferably 10 ° C to 100 ° C, more preferably 20 ° C to 60 ° C. The time for the drying step is not particularly limited as long as it is sufficient for the solvent to evaporate. However, in order to efficiently produce a color filter, it is usually preferably 1 to 30 minutes, more preferably 2 to 20 minutes. preferable.

  When forming colored pixel portions of a plurality of colors in the method for producing a color filter of the present invention, a drying step is performed after at least two types of ink A are each discharged to a predetermined recess in the first discharge step, and then the second discharge step. In order to improve the flatness of the pixel and the ink overflows, it is preferable to discharge the ink B into the concave portion where the ink A is discharged.

The inkjet method used in the color filter manufacturing method of the present invention includes a method in which charged ink is continuously ejected and controlled by an electric field, a method in which ink is ejected intermittently using a piezoelectric element, and ink is heated to Various methods such as a method of intermittent injection using foaming can be adopted.
As the ink ejection conditions, it is preferable from the viewpoint of ejection stability that the ink is heated to 30 to 60 ° C. and ejected with the ink viscosity lowered. Inks generally have higher viscosities than water-based inks, and therefore, the viscosity fluctuation range due to temperature fluctuations is large. It is important to keep the ink temperature as constant as possible, since the viscosity variation directly affects the droplet size and the droplet ejection speed and easily causes image quality degradation.

  A well-known head can be applied to the head (inkjet head), and a continuous type or a dot-on-demand type can be used. Among the dot-on-demand types, the thermal head is preferably a type having an operation valve as described in JP-A-9-323420 for discharging. As the piezo head, for example, the heads described in European Patent A277,703, European Patent A278,590 and the like can be used. Among these, the piezo head is more preferable because the influence of heat on the ink-jet ink can be reduced and the selection of usable organic solvents is wide. The head preferably has a temperature control function so that the temperature of the ink can be controlled. It is preferable to set the injection temperature so that the viscosity at the time of ejection is 5 to 25 mPa · s, and to control the ink temperature so that the fluctuation range of the viscosity is within ± 5%. Further, the drive frequency is preferably 1 to 500 kHz. The shape of the nozzle does not necessarily need to be circular, and is not particular about the shape such as an ellipse or a rectangle. The nozzle diameter is preferably in the range of 10 to 100 μm. The nozzle opening itself is not necessarily a perfect circle. In this case, the nozzle diameter is assumed to be a circle equivalent to the area of the opening.

  The method for producing a color filter of the present invention may be referred to as light irradiation (hereinafter sometimes referred to as a first curing step) and / or heating (hereinafter referred to as a second curing step) after the second ejection step. .) May have a curing step of curing the curable compound.

Hereinafter, the first curing step and the second curing step will be described.
-First curing step-
The first curing step may be performed each time a colored pixel portion of one color is formed, or may be performed after forming a colored pixel portion of a plurality of colors.
Examples of the light beam used in the first curing step include the above-described light such as ultraviolet rays of 400 to 200 nm, far ultraviolet rays, g rays, h rays, i rays, KrF excimer laser light, ArF excimer laser light, and X rays. Those sensitive to polymerization initiators and photoacid generators can be appropriately selected and used. Specifically, a light source that emits actinic rays belonging to a wavelength region of 250 to 450 nm, preferably 365 ± 20 nm, for example, LD, LED (light emitting diode), fluorescent lamp, low pressure mercury lamp, high pressure mercury lamp, metal halide lamp, carbon arc lamp. , Xenon lamps, chemical lamps and the like. Preferred light sources include LEDs, high pressure mercury lamps, and metal halide lamps.

  The irradiation time of the light can be appropriately set according to the combination of the curable compound and the curing component, and can be, for example, 1 to 30 seconds.

-Second curing step-
Examples of the heating method used in the second curing step include a method in which the substrate on which the colored pixel portion and the partition wall are formed is heated in an electric furnace, a dryer or the like, or is heated by irradiation with an infrared lamp. It is done.

  The heating temperature at this time depends on the combination of the curable compound and the curing component and the thickness of the colored pixel portion, but generally 200 ° C. or higher is required from the viewpoint of ensuring sufficient solvent resistance, alkali resistance, and ultraviolet absorbance. Preferably, 210 degreeC or more is more preferable. The heating time is preferably about 10 minutes to about 120 minutes.

  In the method for producing a color filter of the present invention, the colored pixel portion may be cured only in the first curing step, or may be cured only in the second curing step. By curing the colored pixel portion through the second curing step, both the production efficiency of the color filter and the display characteristics can be achieved.

(Partition wall)
In the present invention, a colored pixel portion is formed by ejecting ink by a inkjet method in a recess surrounded by a partition formed on a substrate. This partition may be any type, but is preferably a light-blocking partition having a black matrix function. The partition walls can be produced by the same material and method as those of known black matrixes for color filters. For example, paragraph numbers [0021] to [0074] of JP-A-2005-3861, black matrixes described in paragraph numbers [0012] to [0021] of JP-A-2004-240039, and JP-A 2006-17980 are disclosed. And the inkjet black matrix described in paragraphs [0009] to [0044] of JP-A No. 2006-10875.
Among the known production methods, it is preferable to use a photosensitive resin transfer material from the viewpoint of cost reduction. The photosensitive resin transfer material is a material in which at least a light-shielding resin layer is provided on a temporary support, and the resin layer having a light-shielding property can be transferred to the substrate by pressure bonding to the substrate.

The photosensitive resin transfer material is preferably formed as a photosensitive resin transfer material described in JP-A-5-72724, that is, an integrated film. As an example of the structure of the integral film, there may be mentioned a structure in which a temporary support / thermoplastic resin layer / intermediate layer / photosensitive resin layer / protective film are laminated in this order.
Regarding the temporary support, the thermoplastic resin layer, the intermediate layer, the protective film, and the production method of the transfer material constituting the photosensitive resin transfer material, see paragraphs [0023] to [0066] of JP-A-2005-3861. Those described are preferred.

  The partition wall may be subjected to ink repellent treatment to prevent color mixing of the inkjet ink. As for the ink repellent treatment, for example, (1) a method of kneading an ink repellent substance into a partition wall (for example, see JP-A-2005-36160), and (2) a method of newly providing an ink repellent layer (for example, a special method) (See Kaihei 5-241101), (3) Method of imparting ink repellency by plasma treatment (for example, see JP-A-2002-62420), (4) Method of applying an ink-repellent material to the upper surface of the partition wall (See, for example, Japanese Patent Application Laid-Open No. 10-123500). In particular, (3) a method of performing an ink repellent treatment with plasma on a partition formed on a substrate is preferable.

  After forming the color pixel portion and the partition wall as described above to produce the color filter, an overcoat layer can be formed so as to cover the entire surface of the color pixel portion and the partition wall for the purpose of improving the durability.

The overcoat layer can protect the colored pixel portions such as R, G, and B and the partition walls, and can flatten the surface. However, it is preferable not to provide from the point which the number of processes increases.
An overcoat layer can be comprised using resin (OC agent), and acrylic resin composition, an epoxy resin composition, a polyimide resin composition etc. are mentioned as resin (OC agent). Among them, an acrylic resin composition is desirable because it is excellent in transparency in the visible light region, and the resin component constituting the colored pixel portion usually contains an acrylic resin as a main component and has excellent adhesion. Examples of the overcoat layer include those described in paragraphs [0018] to [0028] of JP-A No. 2003-287618, and commercially available overcoat agents such as Optomer SS6699G manufactured by JSR.

  The color filter of the present invention is produced by the above-described method for producing the color filter of the present invention, and includes, for example, a portable terminal such as a television, a personal computer, a liquid crystal projector, a game machine, and a mobile phone, a digital camera, and a car navigation system. It can be suitably applied to applications such as without particular limitation. In the color filter of the present invention, at least one of color pixels such as red (R), green (G), and blue (B) may be formed by the method for producing a color filter of the present invention.

<Display device>
The display device of the present invention is not particularly limited as long as it includes the color filter of the present invention described above. Display devices such as liquid crystal display devices, plasma display display devices, EL display devices, CRT display devices, etc. Is mentioned. For the definition of display devices and explanation of each display device, refer to “Electronic Display Devices (Akio Sasaki, published by Industrial Research Institute 1990)”, “Display Devices (Junaki Ibuki, Industrial Books Co., Ltd.) Issue)).

  Among the display devices of the present invention, a liquid crystal display device is particularly preferable. The liquid crystal display device is described in, for example, “Next-generation liquid crystal display technology (edited by Tatsuo Uchida, published by Kogyo Kenkyukai 1994)”. The liquid crystal display device to which the present invention can be applied is not particularly limited, and can be applied to various types of liquid crystal display devices described in, for example, the “next generation liquid crystal display technology”. Among these, the present invention is particularly effective for a color TFT liquid crystal display device. The color TFT liquid crystal display device is described in, for example, “Color TFT liquid crystal display (issued in 1996 by Kyoritsu Publishing Co., Ltd.)”. Furthermore, the present invention can be applied to a liquid crystal display device with a wide viewing angle such as a lateral electric field driving method such as IPS and a pixel division method such as MVA. These methods are described, for example, on page 43 of "EL, PDP, LCD display-latest technology and market trends-(issued in 2001 by Toray Research Center Research Division)".

  In addition to the color filter, the liquid crystal display device includes various members such as an electrode substrate, a polarizing film, a retardation film, a backlight, a spacer, and a viewing angle compensation film. For example, “'94 Liquid Crystal Display Peripheral Materials and Chemicals Market (Kentaro Shima, CMC 1994)” and “2003 Liquid Crystal Related Markets Current Status and Future Prospects (Volume 2)” (Table Yoshiyoshi) Fuji Chimera Research Institute, published in 2003) ”.

  The display device of the present invention includes ECB (Electrically Controlled Birefringence), TN (Twisted Nematic), IPS (In-Plane Switching), FLC (Ferroelectric Liquid Crystal), and OCB (OpticBandNyStic). Various display modes such as (Vertical Aligned), HAN (Hybrid Aligned Nematic), and GH (Guest Host) can be adopted. The display device of the present invention is characterized by including the color filter as described above, so that there is no display unevenness when mounted on a television or a monitor, and a wide color reproduction range and a high contrast ratio can be obtained. The display device of the present invention can also be suitably used for large screen display devices such as personal computer displays and television monitors.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited by the following Example.

(Synthesis of binder epoxy compound)
In a four-necked flask equipped with a thermometer, a reflux condenser, a stirrer, and a dropping funnel, 1,3-butylene glycol diacetate (hereinafter referred to as solvent that does not contain a hydroxyl group) (the initial charge solvent) (hereinafter, referred to as the mixing ratio shown in Table 1) 40.7 parts by mass), and heated with stirring to 140 ° C. Next, 54.7 parts by mass of a monomer having the composition described in Table 1 and a polymerization initiator mixture (dropping component) at a temperature of 140 ° C. was dropped at a constant rate from a dropping funnel over 2 hours. After completion of the dropping, the temperature was lowered to 110 ° C., and 4.6 parts by mass of a mixture (additional catalyst component) of 1,3-butylene glycol diacetate (1,3-BGDA) which is a solvent not containing a polymerization initiator and a hydroxyl group was added. The binder epoxy compound having a weight average molecular weight of 9000 was obtained by terminating the reaction at a temperature of 110 ° C. for 2 hours. The weight average molecular weight is a value in terms of polystyrene by the GPC method.

In addition, the symbol in Table 1 is as follows.
GMA: glycidyl methacrylate MMA: methyl methacrylate perbutyl O: t-butyl peroxy 2-ethylhexanoate (manufactured by NOF Corporation)

(Preparation of blue inkjet ink for color filter (B ink 1A))
(1) Preparation of pigment dispersion Each pigment, pigment dispersant, and organic solvent are mixed in the following ratio, 500 parts by mass of zirconia beads having a diameter of 0.3 mm are added, and a paint shaker (manufactured by Asada Steel Corporation) is used. After dispersion for 4 hours, PB15: 6 (CI Pigment Blue 15: 6) pigment dispersion and PV23 (CI Pigment Violet 23) pigment dispersion were prepared.

[Composition of pigment dispersion]
-Each pigment: 10 parts by mass-Pigment dispersant (Disperbyk161 (manufactured by Big Chemie Japan) (solid content 30% by mass in solvent 1,3-BGDA)): 10 parts by mass-Pigment dispersion aid (N-phenylmaleimide / Benzyl methacrylate copolymer (solid content 30% by mass in solvent 1,3-BGDA): 10 parts by mass, 1,3-BGDA: 70 parts by mass

(2) Preparation of binder solution As shown in the composition below, a solvent, a binder epoxy compound, a polyfunctional epoxy resin, a surfactant, etc. are mixed and stirred at 25 ° C. for 60 minutes, and then it is confirmed that there is no insoluble matter. Thus, a binder solution was obtained.

[Binder solution composition]
-Binder epoxy compound solution (solid content 30% by mass in 1,3-BGDA): 15 parts by mass-Multifunctional epoxy resin (trade name Epicoat 154, manufactured by Yuka Shell Epoxy): 3 parts by mass-Neopentyl Glycol glycidyl ether: 1.5 parts by mass
-1,3-BGDA (1,3-butylene glycol diacetate): 25.5 parts by mass-n-decane: 5.0 parts by mass

  The prepared binder solution (50 parts by mass) is slowly added to a mixed solution of PB15: 6 pigment dispersion (46.8 parts by mass) and PV23 pigment dispersion (3.2 parts by mass) at room temperature with stirring. An inkjet ink (B ink 1A) was produced.

(3) Preparation of polymerization accelerating liquid (ink 1B-1) 3.0 parts by mass of trimellitic acid was dissolved in 30 parts by mass of tripropylene glycol monomethyl ether to prepare a polymerization accelerating liquid (ink 1B).
(4) Preparation of polymerization accelerating liquid (ink 1B-2) Ink 1B- was prepared in the same manner as ink 1B-1, except that trimellitic acid in ink 1B-1 was changed to n-propyl vinyl ether blocked trimellitic acid. 2 was prepared. The n-propyl vinyl ether blocked trimellitic acid used here was prepared according to Synthesis Example 3 of JP-A-2005-99404 and purified from the resulting solution.

  Same as B ink 1A, except that in the preparation of the blue inkjet ink for color filter (B ink 1A), 3.0 parts by mass of 15.5 parts by mass of 1,3-BGDA in the binder solution was replaced with trimellitic acid. Thus, B ink 2 was prepared.

[Preparation of dark color composition for barrier rib formation]
The dark color composition K1 is first weighed in the amounts of K pigment dispersion 1 and propylene glycol monomethyl ether acetate listed in Table 2, mixed at a temperature of 24 ° C. (± 2 ° C.), stirred at 150 rpm for 10 minutes, While stirring, the amounts of methyl ethyl ketone, binder 2, hydroquinone monomethyl ether, DPHA solution, 2,4-bis (trichloromethyl) -6- [4 ′-(N, N-bisethoxycarbonylmethyl) amino listed in Table 2 -3′-bromophenyl] -s-triazine and surfactant 1 are weighed and added in this order at a temperature of 25 ° C. (± 2 ° C.) and stirred at a temperature of 40 ° C. (± 2 ° C.) at 150 rpm for 30 minutes. Can be obtained. In addition, the quantity of Table 2 is a mass part, and has the following composition in detail.

<K pigment dispersion 1>,
・ Carbon black (Nippex 35 manufactured by Degussa) 13.1%
・ Dispersant (Compound 1 below) 0.65%
-Polymer (benzyl methacrylate / methacrylic acid = 72/28 molar ratio random copolymer, molecular weight 37,000) 6.72%
Propylene glycol monomethyl ether acetate 79.53%

<Binder 2>
・ Polymer (benzyl methacrylate / methacrylic acid = 78/22 molar ratio random copolymer, molecular weight 38,000) 27%
・ Propylene glycol monomethyl ether acetate 73%

<DPHA solution>
Dipentaerythritol hexaacrylate (containing 500 ppm of polymerization inhibitor MEHQ, manufactured by Nippon Kayaku Co., Ltd., trade name: KAYARAD DPHA) 76%
・ Propylene glycol monomethyl ether acetate 24%

<Surfactant 1>
・ The following structure 1 30%
・ Methyl ethyl ketone 70%

(Formation of partition walls)
The alkali-free glass substrate was cleaned with a UV cleaning apparatus, then brush-cleaned with a cleaning agent, and further ultrasonically cleaned with ultrapure water. The substrate was heat treated at 120 ° C. for 3 minutes to stabilize the surface state.
After cooling the substrate and adjusting the temperature to 23 ° C., a dark color prepared as described above with a glass substrate coater (manufactured by FS Asia Co., Ltd., trade name: MH-1600) having a slit-like nozzle. Composition K1 was applied. Subsequently, a part of the solvent was dried with a VCD (vacuum drying apparatus, manufactured by Tokyo Ohka Kogyo Co., Ltd.) for 30 seconds to eliminate the fluidity of the coating layer, and then pre-baked at 120 ° C. for 3 minutes to obtain a thick film having a thickness of 2.3 μm. A color composition layer K1 was obtained.
In a proximity type exposure machine (manufactured by Hitachi High-Tech Electronics Engineering Co., Ltd.) with an ultra-high pressure mercury lamp, the exposure mask surface and dark color composition with the substrate and mask (quartz exposure mask with image pattern) standing vertically The distance between the physical layers K1 was set to 200 μm, and pattern exposure was performed in a nitrogen atmosphere with an exposure amount of 300 mJ / cm ² to a partition wall width of 20 μm and a space width of 100 μm.
Next, pure water is sprayed with a shower nozzle to uniformly moisten the surface of the dark color composition layer K1, and then a KOH developer (containing a nonionic surfactant, trade names: CDK-1, Fuji Film). Electronics Materials Co., Ltd. 100-fold diluted) was subjected to shower development at 23 ° C. for 80 seconds and a flat nozzle pressure of 0.04 MPa to obtain a patterning image. Subsequently, ultrapure water is sprayed at a pressure of 9.8 MPa with an ultrahigh pressure cleaning nozzle to remove the residue, and the dark composition layer K1 of the substrate is formed at an exposure amount of 2500 mJ / cm ^{2 in} the atmosphere. Post-exposure was performed from the opposite side, and heating was performed at 240 ° C. for 50 minutes in an oven to obtain a stripe-shaped partition wall having an opening having a thickness of 2.0 μm, an optical density of 4.0, and a width of 100 μm.

[Ink repellent plasma treatment]
The substrate on which the barrier ribs were formed was subjected to ink repellent plasma treatment under the following conditions using a cathode coupling parallel plate type plasma treatment apparatus.
Gas used: CF ₄
Gas flow rate: 80sccm
Pressure: 40Pa
RF power: 50W
Processing time: 30 sec

Example 1
-Formation of blue pixel area by inkjet method-
In this example, ink was ejected in the following manner.
The inkjet head used was SE-128 manufactured by Dimatix, and the discharge control device used was Apollo II manufactured by Dimatix.
The inkjet head is mounted on an automatic two-dimensional moving stage (KS211-200 manufactured by Suruga Seiki), and the stage is moved from the head by the discharge control device while moving the stage so that a predetermined amount of ink is discharged into the gap between the partition walls produced above. The discharge was synchronized.
Here, the above-described B ink 1A was filled in the first head, and was controlled by the ejection control device so that the ink landed at a predetermined position.
For the droplet ejection, the B ink 1A is discharged until a desired density is reached, and when 30 seconds have elapsed after the discharge, the ink is heated and dried at 100 ° C. for 2 minutes using a hot plate to remove the solvent in the B ink 1A (drying). Process).
Subsequently, in the same pixel as the pixel from which the B ink 1A was ejected with the transparent curing accelerating liquid (ink 1B-1), trimellitic acid was 15% with respect to the solid content of the colored material forming the pixel. Was discharged. One minute after the discharge was completed, both the partition walls and the pixels were completely cured by baking in an oven at 230 ° C. for 30 minutes, and a blue pixel portion (B1a) for a color filter was produced.

(Example 2)
In Example 1, a blue pixel portion (B1b) was produced in the same manner as in Example 1 except that the ink 1B-2 was used instead of the curing accelerating liquid (ink 1B-1). In this case, the ejection amount of the ink 1B-2 was adjusted so that the amount of trimellitic acid generated by heat from the n-propyl vinyl ether blocked trimellitic acid was the same as that in Example 1.
(Example 3)
In Example 1, after discharging the B ink 1A, the curing accelerating liquid (ink 1B-1) was discharged into the same pixel as the pixel from which the B ink 1A was discharged without performing hot plate drying at 100 ° C. for 2 minutes. Produced a blue pixel portion (B1c) in the same manner as in Example 1.

(Comparative Example 1)
In Example 1, B ink 2 was used instead of B ink 1A, and after heating and drying on a hot plate at 100 ° C. for 2 minutes, the curing accelerating liquid (ink 1B-1) was not discharged in a 230 ° C. oven. A blue pixel portion (B2) of a comparative example was produced in the same manner as in Example 1 except that baking was performed for 30 minutes.

-Evaluation of ink and pixel part-
(Ink performance evaluation)
The stability of the B ink 1A and B ink 2 used in the above examples and comparative examples was evaluated on the following items.

<Storage stability>
The viscosity at 25 ° C. of ink prepared using an E-type viscometer (RE-80L) manufactured by Toki Sangyo Co., Ltd. was measured under the following conditions.
(Measurement condition)
-Rotor used: 1 ° 34 'x R24
・ Measurement time: 2 minutes ・ Measurement temperature: 25 ° C
The ink was allowed to stand at room temperature (23 ° C.) for 3 days, and the viscosity was measured again by the same method to evaluate the change in viscosity.

<Dischargeability>
a) Continuous ejection properties After using the inkjet head and ejection control device used in Example 1 to fill the head with ink and ejecting continuously for 5 minutes at an ejection frequency of 1000 Hz, the ejection was stopped for 30 seconds, When the discharge was started again, the number of nozzles that could not be discharged out of 128 nozzles was counted and evaluated according to the following criteria.

(Evaluation criteria for ejection properties)
○: The number of nozzles that became unable to discharge is 0 to 1
Δ: 〃 2-5
×: ＞> 5

b) Intermittent ejection property In the same manner as the above-described continuous ejection property, ink is filled in the head, and after confirming that ink is ejected from all nozzles, ejection is stopped for 10 minutes, and when ejection is started again, 128 The number of nozzles that could not be discharged among the nozzles was counted and evaluated based on the same criteria as the above-mentioned continuous discharge property.

<Evaluation of flatness of pixel portion>
For the blue pixel parts B1a, B1b, B1c and B2, the shape profile of the pixel part is measured using a non-contact type three-dimensional shape measuring device Zygo manufactured by Zygo, and the height difference obtained by subtracting the minimum film thickness from the maximum film thickness is obtained. Calculated.

  Table 3 shows the ink evaluation results, and Table 4 shows the flatness evaluation results of the pixel portions.

From the above Tables 3 and 4, according to the method for producing a color filter of the present invention, it is possible to obtain a color filter that is excellent in the stability and ejection properties of the ink as a material and that has a good flatness in the finished colored pixel portion. I understand.
In particular, it can be seen that better flatness can be obtained by performing the drying step between the first discharge step and the second discharge step.

<Evaluation with display device>
(Preparation of red inkjet ink for color filter (R ink 1A) and green inkjet ink for color filter (G ink 1A))
A PR254 pigment dispersion was prepared in the same manner as B ink 1A, except that the pigment was changed from PB15: 6 and PV23 to PR254 (CI Pigment Red 254). In addition, a PG36 pigment dispersion and a PY150 pigment dispersion were prepared in the same manner as B ink 1A, except that PG36 (CI Pigment Green 36) and PY150 (CI Pigment Yellow 150) were used.
Next, instead of the mixed liquid of 46.8 parts by mass of PB15: 6 pigment dispersion and 3.2 parts by mass of PV23 pigment dispersion, 50.0 parts by mass of PR254 pigment dispersion was used for R ink, and G ink In the same manner as B ink 1A, except that 30.0 parts by mass of PG36 pigment dispersion and 20.0 parts by mass of PY150 pigment dispersion were used, the red inkjet ink for color filter (R ink 1A) and the color filter were used. A green inkjet ink (G ink 1A) was prepared.
Similarly to B ink 2, R ink 2 and G ink 2 corresponding to R ink 1A and G ink 1A were prepared.

(Production of RGB color filter)
Using the ink sets 1 to 3 of R, G, and B inkjet inks shown in Table 5 below, as a three-color inkjet head, it has a head portion including three SE-128s manufactured by Dimatix, and discharge control Ink-repellent plasma using an ink-jet ink ejecting apparatus having a dedicated piezo drive circuit and stage control dedicated circuit as an apparatus, under the droplet ejection conditions described in the above-mentioned “Formation of pixel portion (B pixel) by inkjet method” Color filters (CF1 to CF3) were manufactured by ejecting ink into the recesses defined by the partition of the glass substrate having the black matrix (partition) that had been processed. The amount of ink ejected at this time was adjusted so that the average height of the pixel portion composed of ink was the same as the height of the partition walls.
The color filters (CF1 to CF3) were produced according to the steps shown in Table 6. Here, in the same manner as in Example 1 for both CF1 to CF3, the drying process was performed by heating and drying on a hot plate at 100 ° C. for 2 minutes, and the curing process was performed by baking in a 230 ° C. oven for 30 minutes.

(Production of liquid crystal display device)
For each of the color filter substrates (CF1 to CF3) obtained above, ITO (Indium Tin Oxide) transparent electrodes were formed by sputtering on the R pixel, G pixel, B pixel, and black matrix (partition). . Separately, a glass substrate was prepared as a counter substrate, and patterning was performed for the PVA mode on the transparent electrode and the counter substrate of the color filter substrate, respectively.
A photo spacer was provided in a portion corresponding to the upper part of the black matrix (partition) on the ITO transparent electrode, and an alignment film made of polyimide was further provided thereon.
Then, a UV curable resin sealant is applied to the position corresponding to the outer wall of the partition wall surrounding the pixel group of the color filter by a dispenser method, and the PVA mode liquid crystal is dropped and bonded to the counter substrate. Thereafter, the bonded substrate was irradiated with UV, and then heat-treated to cure the sealing agent. Polarizing plates HLC2-2518 manufactured by Sanlitz Co., Ltd. were attached to both surfaces of the liquid crystal cell thus obtained. Next, a backlight of a cold cathode tube was constructed and placed on the side of the liquid crystal cell provided with the polarizing plate, thereby producing liquid crystal display devices 1 to 3.

(Evaluation of liquid crystal display devices)
The obtained liquid crystal display device was evaluated for color unevenness by the following method. The results are shown in Table 7.

(Color unevenness evaluation method)
Gray images were displayed for the obtained liquid crystal display devices 1 to 3, and the degree of color unevenness was visually evaluated according to the following evaluation criteria.
-Evaluation criteria-
○: Color unevenness is not observed.
Δ: Color unevenness is slightly observed.
X: Color unevenness is clearly observed.

  From the results in Table 7, it can be seen that by using the method for producing a color filter of the present invention, a liquid crystal display device with less color unevenness and color loss and excellent display quality can be produced.

Claims (16)

A color filter manufacturing method for forming a colored pixel portion by ejecting ink by an inkjet method into a recess surrounded by a partition formed on a substrate,
A first ejection step of ejecting ink A including at least a colorant, an organic solvent, and a component that is polymerized and cured by light and / or heat using the first head into the recess; and the first head A second ink that discharges ink B including at least a component that initiates and / or accelerates curing of a component that is polymerized and cured by light and / or heat using a different second head to the recessed portion where the ink A is discharged. A color filter manufacturing method comprising: a discharge step.   The method for producing a color filter according to claim 1, wherein at least one of the components that are polymerized and cured by light and / or heat is an epoxy compound.   The method for producing a color filter according to claim 1, wherein the component that initiates and / or accelerates the curing is an acidic substance.   The method for producing a color filter according to claim 1 or 2, wherein the component that initiates and / or accelerates the curing is a substance that generates an acid by light and / or heat.   A component that has a drying step for removing the organic solvent contained in the ink A between the first discharge step and the second discharge step, and the drying step is polymerized and cured by the light and / or heat. The method for producing a color filter according to any one of claims 1 to 4, wherein the method is performed under a condition in which the polymer is not polymerized.   85% by mass or more of the organic solvent contained in the ink A is composed of a compound having a boiling point at normal pressure of 180 ° C. to 280 ° C. and a vapor pressure at room temperature of 0.5 mmHg or less. The manufacturing method of the color filter of any one of Claims 1-5.   The method for producing a color filter according to claim 1, wherein the colorant is an organic pigment.   The method for producing a color filter according to claim 7, wherein the number average particle diameter of the organic pigment is 100 nm or less.   The method for producing a color filter according to claim 1, wherein the ink A further contains a surfactant.   10. The method for producing a color filter according to claim 1, wherein the viscosity of the ink A at 25 ° C. is 5 mPa · s or more and 30 mPa · s or less.   11. The method according to claim 1, wherein, in the first ejection step, at least red ink A, green ink A, and blue ink A are each ejected to a predetermined recess. The manufacturing method of the color filter as described in a term.   In the first ejection step, at least two types of ink A are each ejected to a predetermined recess, and then the drying step is performed, and then the ink B is ejected to the recess in which the ink A is ejected in the second ejection step. The method for producing a color filter according to any one of claims 5 to 11, wherein:   13. The method according to claim 1, further comprising a curing step of curing a component that is polymerized and cured by the light and / or heat by light irradiation and / or heating after the second ejection step. The manufacturing method of the color filter of 1 item | term.   The method for producing a color filter according to claim 13, wherein a heating temperature in the curing step is 200 ° C. or higher.   The color filter manufactured by the manufacturing method of the color filter of any one of Claims 1-14.   A display device comprising the color filter according to claim 15.