JP2011075799A - Method of manufacturing color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing color filter for suppressing luminance decrease, after curing in a heating process and reducing degassing in a post-process. <P>SOLUTION: The method of forming color filter includes (i) a process of forming ink layers 33B, G, R by selectively applying inkjet ink compositions, containing a thermosetting binder on prescribed regions on a transparent substrate 5 by an inkjet system; and (ii) a process of curing the ink layer to form a pixel, by sequentially performing for the ink layers a drying process, a process of heating at a temperature lower than a thermal decomposition temperature of a component in the inkjet ink composition which does not contribute to thermosetting reaction, and a process of heating at a temperature of 200 to 250°C. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a color filter in which pixels having a predetermined pattern are formed on a substrate.

  In recent years, with the development of personal computers, particularly portable personal computers, the demand for liquid crystal display devices, particularly color liquid crystal display devices, has been increasing. However, since this color liquid crystal display device 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 a high specific gravity. A typical example of a color filter structure used in a liquid crystal display device will be described with reference to FIGS.

  In general, as shown in FIG. 1A, a color liquid crystal display device (101) is provided with a gap portion 3 of about 1 to 10 μm with a color filter 1 and an electrode substrate 2 such as a TFT substrate facing each other. 3 is filled with a liquid crystal compound L, and the periphery thereof is sealed with a sealing material 4. The color filter 1 includes a light shielding portion 6 formed in a predetermined pattern on the transparent substrate 5 to shield the boundary between pixels, and a plurality of colors (usually R (red)) to form each pixel. , G (green), B (blue) three primary colors) arranged in a predetermined order, a protective film 8 and a transparent electrode film 9 are stacked in this order from the side close to the transparent substrate. I'm taking it. An alignment film 10 is provided on the inner surface side of the color filter 1 and the electrode substrate 2 facing the color filter 1. Furthermore, a spacer is provided in the gap portion 3 in order to maintain a constant and uniform cell gap between the color filter 1 and the electrode substrate 2. As the spacer, pearls 11 having a constant particle diameter are dispersed, or columnar spacers 12 having a height corresponding to the cell gap as shown in FIG. 6 is formed in a region overlapping with the position where 6 is formed. A color image is obtained by controlling the light transmittance of each of the pixels colored in each color or the liquid crystal layer behind the color filter.

  As a conventional method for producing a color filter, there 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. However, in this method, in order to color the three colors of R, G, and B, it is necessary to repeat the same process three times, which increases the cost, and the yield decreases because the same process is repeated. There is a problem.

  In order to solve these problems, a technique for forming a colored layer (pixel portion) by spraying a colored ink containing a thermosetting resin on a substrate by an ink jet method and heating is proposed (for example, patents). Reference 1).

JP 2008-76693 A

  In the method for producing a color filter by the inkjet method, the colored layer (pixel) is formed by heating and curing the colored ink (ink layer) sprayed on the substrate at about 120 ° C. to about 250 ° C. for about 10 minutes to about 120 minutes. Part). In this way, since the colored ink is heated at a high temperature, a component that does not contribute to the thermosetting reaction in the colored ink undergoes thermal decomposition, resulting in a decomposition product. And there existed a problem that the brightness | luminance after hardening fell because the said decomposition product oxidizes resin and yellows.

  After forming the colored layer on the substrate, a protective film is formed on the side of the substrate on which the colored layer is formed. Then, a step of forming a transparent electrode film (indium tin oxide (ITO)) for driving a liquid crystal on the protective film, a step of providing a spacer at a predetermined position on the ITO film, the ITO film and the spacer A color filter is obtained through a step of forming an alignment film (hereinafter, these steps are collectively referred to as a post-step). In this subsequent process, when heat is applied, degass are generated due to decomposition products in the colored layer, and the ITO film peels off, wrinkles, floats, etc., which may cause display defects. there were.

  The present invention has been made in view of the above problems, and provides a method for producing a color filter capable of suppressing a decrease in luminance after curing due to a heating process and reducing generation of degas in the subsequent process. There is to do.

As a result of intensive studies, the present inventors have heated the ink layer at a temperature lower than the thermal decomposition temperature of components that do not contribute to the thermosetting reaction in the inkjet ink composition, and then heated at a high temperature of 200 to 250 ° C. As a result, the inventors have found that the above problems can be solved, and have completed the present invention.
That is, the method for producing a color filter according to the present invention includes:
(I) a step of selectively applying an inkjet ink composition containing a thermosetting binder to a predetermined region on the transparent substrate by an inkjet method to form an ink layer; and (ii) drying the ink layer; Next, the ink layer is heated at a temperature lower than the thermal decomposition temperature of the component that does not contribute to the thermosetting reaction in the inkjet ink composition, and then heated at a temperature of 200 to 250 ° C. Including the step of forming.

In the present invention, when the ink layer is heated, first, a component that does not contribute to the thermosetting reaction is first heated at a temperature lower than the thermal decomposition temperature of the component that does not contribute to the thermosetting reaction in the inkjet ink composition. The thermosetting reaction can proceed without causing thermal decomposition. Thereby, the thermosetting binder in the ink layer forms a network structure. As the thermosetting reaction proceeds and a network structure is formed, oxygen inhibition occurs for components that do not contribute to the thermosetting reaction in the ink layer (network structure). For this reason, it is considered that components that do not contribute to the thermosetting reaction are hardly decomposed even if the ink layer is subsequently heated at a high temperature of 200 to 250 ° C. In addition, it is considered that decomposition products generated by heating the ink layer at a high temperature of 200 to 250 ° C. are less likely to volatilize due to the formation of the network structure.
Therefore, according to the present invention, the thermal decomposition of components that do not contribute to the thermosetting reaction in the ink layer due to heating of the ink layer can be suppressed, the yellowing due to the oxidation of the resin hardly occurs, and after the curing It is possible to provide a color filter capable of suppressing a decrease in luminance. In addition, since thermal decomposition of components that do not contribute to the thermosetting reaction in the ink layer is suppressed and the amount of decomposition products contained in the pixel can be reduced, in the subsequent process, particularly on the pixel or on the pixel. When a protective film is formed on the protective film, generation of degas due to the decomposition product can be suppressed even when heated in the step of forming indium tin oxide (ITO) on the protective film.

  In the method for producing a color filter according to the present invention, examples of the component that does not contribute to the thermosetting reaction include a dispersant and a coloring material. By heating at a temperature lower than the thermal decomposition temperature of the dispersant and the color material, the thermal decomposition of the dispersant and the color material can be suppressed, and yellowing due to oxidation of the resin is less likely to occur. A reduction in luminance can be suppressed.

  In the method for producing a color filter according to the present invention, it is preferable that the dispersant contains a polyallylamine derivative from the viewpoint of improving the shape and film properties of the cured film.

  In the method for producing a color filter according to the present invention, the temperature lower than the thermal decomposition temperature of the component that does not contribute to the thermosetting reaction is 130 to 190 ° C., which suppresses a decrease in luminance after curing and In the process, it is preferable because generation of degas can be suppressed.

  In the method for producing a color filter according to the present invention, the drying is performed under reduced pressure, so that even if the drying is performed in a short time, surface unevenness does not occur, pixels with high flatness can be formed, and display performance is improved. Improvements can be made.

According to the present invention, the ink layer is heated at a temperature lower than the thermal decomposition temperature of a component that does not contribute to the thermosetting reaction in the inkjet ink composition, and then heated at a high temperature of 200 to 250 ° C. Heat decomposition of components that do not contribute to the thermosetting reaction in the ink layer due to heating of the layer can be suppressed, yellowing due to resin oxidation is less likely to occur, and reduction in brightness after curing can be suppressed A color filter can be provided.
In addition, since thermal decomposition of components that do not contribute to the thermosetting reaction in the ink layer is suppressed and the amount of decomposition products contained in the pixel can be reduced, in the subsequent process, particularly on the pixel or on the pixel. When a protective film is formed on the protective film, generation of degas due to the decomposition product can be suppressed even when heated in the step of forming indium tin oxide (ITO) on the protective film. Thereby, peeling of the ITO film, wrinkles, floating, and the like are suppressed, the resistance value is improved, and recoatability and adhesion can be improved.

It is typical sectional drawing about an example of a liquid crystal panel. It is typical sectional drawing about another example of a liquid crystal panel. It is a typical longitudinal cross-sectional view which shows an example of the color filter of this invention. FIG. 3A to FIG. 3E are diagrams for explaining an example of a method for producing a color filter using the inkjet ink of the present invention. It is a typical bird's-eye view showing the undried state of the ink layer of the present invention. It is a typical bird's-eye view showing the drying completion state of the ink layer of the present invention.

The present invention is described in detail below.
I. Manufacturing method of color filter The manufacturing method of a color filter according to the present invention includes: (i) selectively applying an ink-jet ink composition containing a thermosetting binder to a predetermined region on a transparent substrate by an ink-jet method; And (ii) drying the ink layer, then heating at a temperature lower than the thermal decomposition temperature of a component that does not contribute to the thermosetting reaction in the inkjet ink composition, and then 200 to 250 ° C. And heating the ink at a temperature to cure the ink layer to form a pixel.

In the present invention, when the ink layer is heated, first, the component that does not contribute to the thermosetting reaction by heating at a temperature lower than the thermal decomposition temperature of the component that does not contribute to the thermosetting reaction in the inkjet ink composition. The thermosetting reaction can be allowed to proceed without thermally decomposing. Thereby, the thermosetting binder in the ink layer forms a network structure. As the thermosetting reaction proceeds and a network structure is formed, oxygen inhibition occurs for components that do not contribute to the thermosetting reaction in the ink layer (network structure). For this reason, it is considered that components that do not contribute to the thermosetting reaction are hardly decomposed even if the ink layer is subsequently heated at a high temperature of 200 to 250 ° C. In addition, it is considered that decomposition products generated by heating the ink layer at a high temperature of 200 to 250 ° C. are less likely to volatilize due to the formation of the network structure.
Therefore, according to the present invention, the thermal decomposition of components that do not contribute to the thermosetting reaction in the ink layer due to heating of the ink layer can be suppressed, the yellowing due to the oxidation of the resin hardly occurs, and after the curing It is possible to provide a color filter capable of suppressing a decrease in luminance. In addition, since thermal decomposition of components that do not contribute to the thermosetting reaction in the ink layer is suppressed and the amount of decomposition products contained in the pixel can be reduced, in the subsequent process, particularly on the pixel or on the pixel. In the step of forming indium tin oxide (ITO) on the protective film, the generation of degas due to the decomposition product can be suppressed even when heated. Peeling, wrinkling, floating, etc. can be suppressed.

Hereinafter, each step will be described.
(I) Step of selectively applying an ink-jet ink composition containing a thermosetting binder to a predetermined region on a transparent substrate by an ink-jet method to form an ink layer In this step, first, a transparent substrate of a color filter Is prepared (FIG. 3A).
Next, a light shielding portion 6 is formed in a region serving as a boundary between pixel portions on one surface side of the transparent substrate 5 (FIG. 3B). In the case of forming a metal thin film as the light shielding portion 6, it can be formed by patterning the thin film. As the patterning method, a normal patterning method such as a sputtering method or a vacuum deposition method can be used.
Further, when forming a layer containing light-shielding particles such as carbon fine particles, metal oxides, inorganic pigments, and organic pigments in the resin binder as the light-shielding portion 6, as a patterning method, a photolithography method, A generally used method such as a printing method can be used. Or you may form using an inkjet system similarly to the pixel 7 mentioned later.

Next, an ink-jet ink composition for a color filter containing a thermosetting binder (hereinafter sometimes simply referred to as “ink-jet ink composition” or “ink”) is prepared.
The ink-jet ink composition used in the present invention contains a coloring material, a dispersant, and an organic solvent in addition to the thermosetting binder.
Hereinafter, components used in the inkjet ink composition of the present invention will be described.
(Thermosetting binder)
The ink-jet ink composition for a color filter of the present invention contains a binder component in order to impart film formability and adhesion to a coated surface. Since the ink of the present invention is an ink used in an ink jet system, in order to form a predetermined pattern, it can be formed by selectively adhering the ink only to a predetermined pattern formation region and solidifying it. Further, it is not necessary to form a pattern by performing development. Therefore, as a binder component, an ink layer (coating film) pattern is formed on a substrate by an ink jet method in order to impart sufficient strength, durability, and adhesion to the coating film, and then the ink layer is polymerized by heating. A thermosetting binder that can be cured is used. When a thermosetting binder is used, the film physical properties of the pixel such as solvent resistance, adhesion, and ITO resistance can be improved. In addition, ITO tolerance here is tolerance with respect to the malfunction at the time of ITO circuit formation or alignment film formation, and specifically, the heat resistance in 230-250 degreeC after ITO circuit formation is mentioned. In addition, when a thermosetting binder is used, there is an advantage that a special incidental equipment such as a light irradiation device is not necessary and productivity is high.

  As the thermosetting binder, a combination of a compound having two or more thermosetting functional groups in one molecule and a curing agent is usually used, and a catalyst capable of promoting a thermosetting reaction may be added. An epoxy group is preferably used as the thermosetting functional group. Further, these may be used in combination with a polymer having no polymerization reactivity.

i) Compound having two or more thermosetting functional groups in one molecule As a compound having two or more thermosetting functional groups in one molecule, an epoxy compound usually having two or more epoxy groups in one molecule Is 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 the “Epoxy Resin Handbook” edited by Masaki Shinbo, published by Nikkan Kogyo Shimbun (Showa 62). These can be used widely.

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

（Ｒ^６は水素原子または炭素数１〜３のアルキル基であり、Ｒ^７は炭素数１〜１２の炭化水素基である。）

(R ⁶ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ⁷ is a hydrocarbon group having 1 to 12 carbon atoms.)

（Ｒ^８は水素原子又は炭素数１〜１０のアルキル基である。）
式（１）で表される構成単位は、下記式（３）で表されるモノマーから誘導される。

(R ⁸ 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^６およびＲ^７は式（１）と同じである。）

(R ⁶ and R ⁷ 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 cured coating film formed from the ink of the present invention. In the formula (3), R ⁷ 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, or 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. Here, (meth) acrylate means that either acrylate or methacrylate may be used.

In formula (3), R ⁶ is preferably hydrogen or a methyl group, and R ⁷ is preferably an alkyl group having 1 to 12 carbon atoms. Among them, a methyl group and a cyclohexyl group are particularly preferable. 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^８は式（２）と同じである。）

(R ⁸ 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. The ink containing the polymer is excellent in storage stability and hardly increases in viscosity during storage and discharge operations. One of the reasons is that the epoxy group in formula (2) or formula (4) is This is presumed to be due to the glycidyl group. If an alicyclic epoxy acrylate is used instead of the monomer represented by formula (4), the viscosity of the ink tends to increase.

In the formula (4), R ⁸ 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 main chain constituent units other than those of formula (1) or formula (2) as long as 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 to 20,000, and particularly preferably 4,000 to 15,000, when expressed in terms of polystyrene equivalent weight average molecular weight. If the molecular weight of the binder epoxy compound is less than 3,000, physical properties such as strength and solvent resistance required for the cured resin layer as the details of the color filter are likely to be insufficient, while the molecular weight is 20,000. If it is too large, the viscosity is likely to increase, and 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 may be degraded.

  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 110 ° C., a catalyst is added, the reaction is performed for 3 hours, and the reaction is terminated when the temperature is raised to 130 ° C. and maintained for 2 hours, whereby the binder epoxy compound is obtained.

  The thermosetting binder of the present invention is an epoxy compound having two or more epoxy groups in one molecule (hereinafter sometimes referred to as “polyfunctional epoxy compound”), and has a molecular weight higher than that of the binder epoxy compound. Is preferably added. 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.

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

  The polyfunctional epoxy compound is not particularly limited as long as it contains two or more epoxy groups in one molecule. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, brominated bisphenol A type epoxy resin, Bisphenol S type epoxy resin, diphenyl ether type epoxy resin, hydroquinone type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, fluorene type epoxy resin, bisphenol A type novolac type epoxy resin, phenol novolac type epoxy resin, cresol novolak type epoxy resin , Trishydroxyphenylmethane type epoxy resin, trifunctional type epoxy resin, tetraphenylolethane type epoxy resin, dicyclopentadienephenol type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol A nucleated polyol type epoxy resin, polypropylene glycol type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, glioxal type epoxy resin, alicyclic epoxy resin, heterocyclic type epoxy resin, etc. Can be used.

  Among the polyfunctional epoxy compounds, bisphenol A type novolac epoxy resins and cresol novolac type epoxy resins are particularly preferable.

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

ii) Curing agent The thermosetting binder used in the present invention is usually combined with a curing agent.
Examples of the curing agent for the binder epoxy compound include a carboxyl group block compound described in Japanese Patent No. 420680, a thermal initiator described in Japanese Patent Application Laid-Open No. 2006-169495, and an intramolecular described in Japanese Patent No. 3968847. And alkoxysilanes having one or more amidic acid bonds or condensates thereof, and acid anhydride components having one or more amic acid bonds in the molecule described in JP-A No. 11-209565.

  The above curing agents can be used singly or in combination of two or more. The compounding quantity of the hardening | curing agent used for this invention is the range of 1-100 weight part normally with respect to 100 weight part of said binder epoxy compounds, Preferably it is 5-50 weight part. If the blending amount of the curing agent is less than 1 part by weight, curing may be insufficient and a tough coating film may not be formed. Moreover, when the compounding quantity of a hardening | curing agent exceeds 100 weight part, there exists a possibility that the adhesiveness with respect to the board | substrate of a coating film may be inferior.

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

(Dispersant)
The dispersant is blended in the ink in order to favorably disperse the color material. Examples of the dispersant that can be used include cationic, anionic, nonionic, amphoteric, silicone, and fluorine surfactants.

  Among the surfactants, a polymer surfactant having a molecular weight of 1000 or more is preferable. Examples of the polymer surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether; polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, etc. Polyoxyethylene alkylphenyl ethers; polyethylene glycol diesters such as polyethylene glycol dilaurate and polyethylene glycol distearate; sorbitan fatty acid esters; fatty acid-modified polyesters; tertiary amine-modified polyurethanes.

  Further, in the present invention, a polyallylamine derivative is used as a dispersant because the viscosity stability of the ink jet ink composition is improved and a sharp increase in viscosity or clogging is difficult to occur at the nozzle tip of the ink jet head. It is preferable.

  The polyallylamine derivative is preferably a polyallylamine derivative represented by the following general formula (I). For example, polyallylamine and a polyester having a free carboxyl group, polyamide, or a co-condensate of an ester and an amide (polyester) Amide) is obtained by reacting with one or more compounds selected from three types of compounds.

（式中、ＸおよびＹは、それぞれ独立に水素、重合開始剤残基又は連鎖移動触媒残基のいずれかを、Ｒ^９は遊離のアミノ基、下記一般式（ＩＩ）又は（ＩＩＩ）で示される基を、ｎは２〜１，０００の整数を表す。但しｎ個のＲ^９中、少なくとも１個は一般式（ＩＩＩ）で示される基を表す。）

(Wherein X and Y are each independently hydrogen, a polymerization initiator residue or a chain transfer catalyst residue, R ⁹ is a free amino group, and is represented by the following general formula (II) or (III) the group, n is in. However the n ^{R 9} represents an integer of 2 to 1,000, a group of at least one represented by the general formula (III).)

（式中、Ｒ^１０は遊離のカルボン酸を有するポリエステル、遊離のカルボン酸を有するポリアミド、または遊離のカルボン酸を有するポリエステルアミドのいずれかからカルボキシル基を除いた残基を表す。）

(In the formula, R ¹⁰ represents a residue obtained by removing a carboxyl group from either a polyester having a free carboxylic acid, a polyamide having a free carboxylic acid, or a polyester amide having a free carboxylic acid.)

  More specifically, the polyallylamine derivative used in the present invention is represented by the following general formula (IV) or (V) having, for example, a polyallylamine having a polymerization degree of 2 to 1,000 and a free carboxyl group. One kind of a polyester represented by general formula (VI) or (VII) below or a combination of two or more kinds can be used as a raw material.

（式中Ｒ^１１は、炭素原子数２〜２０の直鎖状もしくは分岐のアルキレン基を、そしてａは２〜１００の整数を示す。）

(In the formula, R ¹¹ represents a linear or branched alkylene group having 2 to 20 carbon atoms, and a represents an integer of 2 to 100.)

（式中Ｒ^１２は、炭素原子数２〜２０の直鎖状もしくは分岐のアルキレン基、Ｃ_６Ｈ_４またはＣＨ＝ＣＨを、Ｒ^１３は炭素原子数２〜２０の直鎖状もしくは分岐のアルキレン基、ポリアルキレングリコールから２つの水酸基を除いた残基を、そしてｂは２〜１００の整数を示す。また、前記鎖中にエーテル結合を有することもある。）

(Wherein R ¹² is a linear or branched alkylene group having 2 to 20 carbon atoms, C ₆ H ₄ or CH═CH, and R ¹³ is a linear or branched alkylene group having 2 to 20 carbon atoms. A group, a residue obtained by removing two hydroxyl groups from polyalkylene glycol, and b represents an integer of 2 to 100. The chain may also have an ether bond.)

（式中Ｒ^１４は、炭素原子数２〜２０の直鎖状もしくは分岐のアルキレン基を、そしてｃは２〜１００の整数を示す。）

(Wherein R ¹⁴ represents a linear or branched alkylene group having 2 to 20 carbon atoms, and c represents an integer of 2 to 100.)

（式中Ｒ^１２は、炭素原子数２〜２０の直鎖状もしくは分岐のアルキレン基、Ｃ_６Ｈ_４またはＣＨ＝ＣＨを、Ｒ^１５は炭素原子数２〜２０の直鎖状もしくは分岐のアルキレン基を、そしてｄは２〜１００の整数を示す。）

(Wherein R ¹² is a linear or branched alkylene group having 2 to 20 carbon atoms, C ₆ H ₄ or CH═CH, and R ¹⁵ is a linear or branched alkylene group having 2 to 20 carbon atoms. A group, and d represents an integer of 2 to 100.)

  The polyallylamine derivative used in the present invention is a polyester in which the repeating components of the general formula (IV) and the general formula (V) are randomly polymerized on the polyallylamine, the repeating of the general formula (VI) and the general formula (VII). Manufactured by reacting a polyamide in which the components are randomly polymerized, and further a polyester amide in which the repeating components of the general formulas (IV) and / or (V) and general formulas (VI) and / or (VII) are randomly polymerized. be able to.

The polyallylamine used for the production of the polyallylamine derivative is obtained by polymerizing allylamine in the presence of a polymerization initiator, and in some cases in the presence of a chain transfer catalyst. The number average molecular weight of the polyallylamine used in the present invention is not particularly limited as long as it is 150 to 100,000, but 600 to 20,000 polyallylamine is preferable from the viewpoint of dispersibility of the coloring material.
The molecular weight of the polyester used for the production of the polyallylamine derivative may be in the range of 300 to 20,000, but is preferably 1,000 to 10,000 from the viewpoint of dispersibility of the coloring material.
In addition, it is preferable that the molecular weight of the polyallylamine derivative used for this invention is 2000-100000.

The polyallylamine derivative has an acid amide formation reaction with respect to a polyallylamine having n amino groups at a ratio of 2 mol or more of a terminal carboxyl group of a polyester, polyamide or ester-amide co-condensate (polyesteramide). What has been performed is preferable in terms of dispersibility of the coloring material. In particular, in the general formula (I), it is preferable that the residue in the form bonded by an acid amide bond represented by the general formula (III) in n R ^{1 is} in the range of 60 to 95%, and still more preferable. Are preferably present in a range of 65 to 90% of residues in a form linked by an acid amide bond.

  The polyallylamine derivative has a weight ratio of polyallylamine and polyester having a carboxyl group at one end, polyamide or a co-condensate of ester and amide (polyesteramide), and the obtained polyallylamine The amine value (mgKOH / g) of the derivative is preferably 5 to 30 from the viewpoint of dispersibility of the coloring material.

  As the dispersant for the polyallylamine derivative, commercially available products such as Ajinomoto Fine Techno Co., Ltd .; Ajisper Pb821, Azisper Pb822, Azisper Pb880 and the like can be used.

  In the ink-jet ink composition of the present invention, the content of the dispersant is usually preferably 5 to 100 parts by weight, more preferably 10 to 80 parts by weight with respect to 100 parts by weight of the color material.

(Coloring material)
As the colorant used in the present invention, any one of known organic colorants and inorganic colorants can be selected and used. As the organic colorant, for example, dyes, organic pigments, natural pigments, and the like can be used. Moreover, as an inorganic coloring agent, an inorganic pigment, an extender pigment, etc. can be used, for example. Among these, organic pigments are preferably used because they have high color developability and high heat resistance. Examples of the organic pigment include compounds classified as pigments in the color index (CI; issued by The Society of Dyers and Colorists).

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

  In the ink-jet ink used in the present invention, the coloring material is usually blended in a proportion of 1 to 60% by weight, preferably 15 to 40% by weight, based on the total solid content of the ink-jet ink. When there are too few coloring materials, there exists a possibility that the permeation | transmission density | concentration at the time of apply | coating inkjet ink to a predetermined film thickness (0.5-3.0 micrometers) may not be enough. Moreover, when there are too many coloring materials, the properties as a coating film, such as adhesion to the substrate when the ink-jet ink is applied and cured on the substrate, surface roughness of the cured film, coating film hardness, etc., are insufficient. There is a fear.

(Organic solvent)
The ink composition of the present invention contains an organic solvent in order to prepare the composition into a high-concentration solution or an ink that can be immediately ejected from the head. The organic solvent is not particularly limited as long as it is a solvent that suitably dissolves and disperses solid components in order to prepare a high-concentration ink for storage or an ink that can be applied immediately.

  The ink-jet ink composition of the present invention has a boiling point of 180 ° C. to 260 ° C. in order not to cause a sudden increase in viscosity or clogging of the ink and to improve dischargeability without adversely affecting the straightness and stability of discharge. A solvent component having a vapor pressure of 0.5 mmHg (66.7 Pa) or less, particularly 0.1 mmHg (13.3 Pa) or less, and a vapor pressure at room temperature (particularly in the range of 18 ° C to 25 ° C). It is used as a main solvent, and such main solvent is preferably blended in a proportion of preferably 70% by weight or more, particularly preferably 80% by weight or more, based on the total amount of the organic solvent. When the discharge property is improved, the colored cured layer can be formed accurately and uniformly. Further, the surface tension of the main solvent is preferably 28 mN / m or more from the viewpoint that the outflow of ink to the sparse ink portion during patterning can be reduced. Here, the surface tension at 23 ° C. in the present invention can be measured by a surface tension meter (Wilhelmy method) (for example, an automatic surface tension meter CBVP-Z manufactured by Kyowa Interface Science Co., Ltd.).

  Especially, as a solvent used for the inkjet ink composition of the present invention, the boiling point of the first solvent is 180 ° C. to 260 ° C., preferably 210 ° C. to 260 ° C. and normal temperature (especially in the range of 18 ° C. to 25 ° C.). A solvent component having a vapor pressure of 0.5 mmHg or less, preferably 0.1 mmHg or less is contained in an amount of 60 to 95% by weight based on the total amount of the solvent, and a solvent component having a boiling point of 130 ° C. or more and less than 180 ° C. as a second solvent. It is preferable to contain 5 to 40 weight% with respect to the whole quantity of a solvent. In such a case, the ejectability is good and the tip of the nozzle of the inkjet head does not dry quickly, but the solute can be prevented from flowing when the ink layer is dried, and the drying speed can be adjusted appropriately. It becomes possible. Therefore, a thick film portion is hardly formed at the end of the coating film, and a highly uniform pattern with a reduced film thickness can be obtained and dried efficiently.

  The proportion of the first solvent is preferably 70 to 95% by weight of the total amount of solvent, 75 to 95% by weight of the total amount of solvent, and further 80 to 92% by weight of the total amount of solvent. The ink-jet ink used in the present invention may further contain a small amount of a solvent component other than the first solvent and the second solvent, if necessary. This is because the ink of the present invention uses a pigment as a coloring material, and therefore it may be necessary to use a dispersion solvent that easily disperses the pigment in order to prepare a pigment dispersion.

  Specific examples of solvents that can be used as the main solvent or the first solvent include ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol dibutyl ether, diethyl adipate, dibutyl oxalate, dimethyl malonate, and malon. Examples include diethyl acid, dimethyl succinate, and diethyl succinate. These solvents not only satisfy the requirement that the boiling point is 180 ° C. to 260 ° C. and the vapor pressure at room temperature is 0.5 mmHg or less, but the dispersibility and dispersion stability of the coloring material are also relatively good. A pigment (color) is used as a dispersion solvent without being mixed or mixed with a solvent conventionally used for preparing a pigment (coloring material) dispersion such as 3-methoxybutyl acetate or propylene glycol monomethyl ether acetate (PGMEA). Material) A dispersion can be prepared.

  Furthermore, as these solvents mentioned as specific examples, the standard solution shown in the wettability test specified in JIS K6768 was used, and the contact angle (θ) after 30 seconds was measured by contacting the droplets. The contact angle with respect to the surface of the test piece having a critical surface tension of 30 mN / m determined from the graph of the plot is 25 ° or more, and the contact with the surface of the test piece having a critical surface tension of 70 mN / m determined by the same measurement method. The requirement that the angle is 10 ° or less is satisfied. Therefore, these solvents are also used in the main solvent even in the case where the wettability variable layer is provided on the surface of the substrate for exposure and the ink is selectively attached using the difference in wettability between the exposed and unexposed areas. To the first solvent.

Moreover, the solvent component used as a 2nd solvent is a solvent component whose boiling point is 130 to 180 degreeC. If it is the solvent which has the said boiling point, you may use it individually or in mixture of 2 or more types.
Among these, the boiling point of each solvent component used for the second solvent is 140 ° C. to 180 ° C., particularly 140 ° C. to 175 ° C. This is preferable because a good coating film with reduced unevenness is easily obtained.

  Moreover, it is preferable that the viscosity at 23 degreeC of said 2nd solvent is 0.5-6 mPa * s. In such a case, by including the second solvent, it is possible to appropriately lower the viscosity of the ink without hindering the effect of the first solvent, and the wettability of the ink itself is improved. As a result, the landed ink droplets are likely to wet and spread to every corner of the entire ink layer formation region. As a result, even when the substrate is diversified, it is possible for the landed ink to spread evenly to the wrinkles of the light-shielding portion, preventing pixel color loss and luminance reduction, and further reducing display defects. Color filters can be manufactured. There is also a method of landing ink toward the edge of the region in order to adhere the ink to the corner of the region, but this method may cause the ink to flow out from the gap of the light shielding portion. On the other hand, wetting and spreading to the wrinkle portion of the light shielding portion by the ink itself is a more desirable method from the viewpoint of preventing the ink from flowing out and preventing color mixing between two or more types of ink. The viscosity of the second solvent at 23 ° C. is preferably 0.5 to 3 mPa · s. When two or more kinds of second solvents are used in combination, they are suitably used as long as the viscosity of the mixed solvent is within the above range even if it is outside the above range. Here, the viscosity at 23 ° C. in the present invention can be measured with a falling ball viscometer, for example, an automatic micro viscometer AMVn (Nihon Sibel Hegner Co., Ltd.).

  Examples of the second solvent include ethers including polyhydric alcohol ethers such as glycol ethers and glycerin ethers, polyhydric alcohol esters such as glycol esters and glycerin esters, aliphatic esters, alkoxy compounds. It is preferable to use at least one selected from the group consisting of carboxylic acid esters and esters including ketocarboxylic acid esters. When using the esters and ethers as described above, even when a highly reactive resin is used for the binder component, etc., the ink will maintain good stability over time and be ejected from the inkjet head. There is an advantage that stability is improved. Also, when glycol ethers or glycol esters are used, the wettability with respect to the glass substrate is improved, and the ink layer formation region is easily spread to every corner, which is effective in preventing color loss of pixels. .

  In the inkjet ink composition of the present invention, the content of the second solvent is preferably 5 to 30% by weight, more preferably 5 to 25% by weight, particularly 8 to 20% by weight, based on the total amount of the solvent. , Without disturbing the effect of the first solvent, it has excellent stability when ejected from an inkjet head, can be dried more efficiently, is less likely to produce a thick film portion at the end, and the surface unevenness is reduced. It is preferable because it is easy to form excellent pixels and the like.

  The ink is prepared by using the above solvent in a proportion of usually 40 to 95% by weight with respect to the total amount of the ink containing the solvent. When ink that can be ejected immediately from the head is used, it is appropriately adjusted so as to have a viscosity suitable for ejection from an inkjet. If the amount of the solvent is too small, the viscosity of the ink is high and it becomes difficult to discharge from the inkjet head. Also, if there is too much solvent, the ink will break from the predetermined ink layer formation site, the amount of ink that can be deposited on the ink layer formation site will be insufficient, the film thickness after drying will be too thin, Accordingly, a sufficient transmission density cannot be obtained.

(Other ingredients)
Furthermore, the ink jet ink composition for color filters of the present invention may contain one or more other additives as required. Examples of such additives include fillers, adhesion promoters, leveling agents, ultraviolet absorbers and anti-aggregation agents.

(Method for producing inkjet ink composition)
The ink-jet ink composition used in the present invention may be produced by adding and mixing each component into a solvent that is a single solvent or a mixed solvent, and dissolving or dispersing the solid component.
However, if the coloring material is directly put into the whole solvent together with other components such as a binder system and stirred and mixed, the coloring material is often not sufficiently dispersed in the solvent. Therefore, usually, a solvent having good dispersibility and dispersion stability of the color material is prepared, and the color material is added thereto together with the dispersant and sufficiently stirred by a dissolver or the like to prepare a color material dispersion. Then, the obtained color material dispersion is put together with components other than the color material, for example, into a solvent consisting almost of the first solvent or only of the first solvent, and sufficiently stirred and mixed by a dissolver or the like. Accordingly, the ink-jet ink used in the present invention can be prepared by finally adding the second solvent. Alternatively, the obtained color material dispersion is put together with components other than the color material, for example, into a mixed solvent obtained by adding a second solvent to a solvent consisting almost of the first solvent or consisting of only the first solvent, a dissolver, etc. The ink-jet ink used in the present invention can be prepared by sufficiently stirring and mixing.

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

  Next, on the surface of the transparent substrate 5, a pixel forming inkjet ink of a corresponding color is selectively applied to the pixel forming regions 31R, 31G, and 31B of each color defined by the pattern of the light shielding portion 6 by an inkjet method. Thus, an ink layer is formed (FIG. 3C). The ink layer is formed so that a red pattern, a green pattern, and a blue pattern are arranged in a desired form such as a mosaic type, a stripe type, a triangle type, or a four-pixel arrangement type. In this ink spraying process, the ink-jet ink is unlikely to increase in viscosity at the tip of the head 32, and it is necessary to continue to maintain good ejection properties. In this case, the ink of the corresponding color can be adhered accurately and uniformly in a predetermined pixel formation region, and a pixel portion free from color unevenness and color loss can be formed with an accurate pattern. In addition, since the inkjet ink for pixel formation of each color can be simultaneously sprayed on the substrate using a plurality of heads, the working efficiency is improved as compared with the case where the pixel portion is formed for each color by a method such as printing. Can do.

(Ii) drying the ink layer, and then heating at a temperature lower than the thermal decomposition temperature of a component that does not contribute to the thermosetting reaction in the inkjet ink composition, and then heating at a temperature of 200 to 250 ° C. To form pixels by curing the ink layer (FIG. 3D)
In this step, first, the ink layer is dried to evaporate the solvent.
In the present invention, drying under reduced pressure is performed as a drying method, and even when the ink layer is dried in a short time, surface unevenness does not occur, pixels with high flatness can be formed, and display performance is improved. This is preferable from the point of view. The drying under reduced pressure is usually performed at a temperature of 0 to 60 ° C., preferably 20 to 50 ° C., and a pressure of 0.03 to 0.20 Torr, preferably 0.03 to 0.15 Torr. Further, the drying time under reduced pressure is usually 3 to 30 minutes, preferably 5 to 15 minutes.
Here, when the undried portion 22 remains when the ink layer is dried, the undried portion 22 has a film thickness approximately five times that of the dried portion. For this reason, when the ink layer is not sufficiently dried, when the ink layer is viewed obliquely from 30 to 80 degrees obliquely, the boundary between the undried portion 22 and the dried portion 23 is rounded, and reflection unevenness can be confirmed (see FIG. 4). On the other hand, when the ink layer is completely dried, when the ink layer is viewed from obliquely 30 to 80 degrees obliquely, the reflection appearance looks uniform (FIG. 5).
Therefore, it can be confirmed from the appearance after drying of the ink layer whether or not the undried portion 22 remains.

Moreover, you may pre-bake as needed after drying under reduced pressure. The prebaking temperature may be appropriately determined depending on the components of the ink composition, the use ratio, the type of solvent, and the like, and is usually 60 to 100 ° C., preferably 80 to 100 ° C. By setting the heating temperature within the above range, it is possible to prevent color mixture breakdown with the color material of the adjacent pixel due to bumping and sufficiently dry the remaining volatile components.
Moreover, prebaking time is 5 to 100 minutes normally, Preferably it is 5 to 60 minutes.

Next, the dried ink layer is heated at a temperature lower than the thermal decomposition temperature of the component that does not contribute to the thermosetting reaction in the inkjet ink composition.
Here, the component that does not contribute to the thermosetting reaction in the inkjet ink composition is a component other than the thermosetting binder, the curing agent, and the catalyst contained in the inkjet ink composition, and means a component that is not a solvent. .
Examples of the component that does not contribute to the thermosetting reaction in the inkjet ink composition include a dispersant and a coloring material. Moreover, the temperature lower than the thermal decomposition temperature means a temperature lower than any thermal decomposition temperature of the component occupying 5% by weight or more with respect to the total weight of the component not contributing to the thermosetting reaction. Usually, since the total amount of the dispersant and the coloring material exceeds 95% by weight with respect to the total weight of the components that do not contribute to the thermosetting reaction, if the temperature is lower than the thermal decomposition temperature of these two components, the thermal decomposition temperature is exceeded. Satisfy low temperature. By heating at a temperature lower than the thermal decomposition temperature of the dispersant and the color material, the thermal decomposition of the dispersant and the color material can be suppressed.

The temperature lower than the thermal decomposition temperature of the component that does not contribute to the thermosetting reaction is set such that the difference from the lowest thermal decomposition temperature is 70 ° C. or less among the components that do not contribute to the thermosetting reaction.
Specifically, the temperature lower than the thermal decomposition temperature of the component that does not contribute to the thermosetting reaction is preferably 130 to 190 ° C, more preferably 140 to 170 ° C. The heating time is preferably 5 to 60 minutes, more preferably 10 to 30 minutes. By setting the heating temperature and the heating time within the above ranges, the thermosetting reaction can sufficiently proceed without thermally decomposing components (dispersant and coloring material) that do not contribute to the thermosetting reaction in the ink composition. it can.
As a heating method, heating with an electric furnace, an IR heater, a hot plate, a microwave, or the like can be given.

Heating is performed at a temperature lower than the thermal decomposition temperature of the component that does not contribute to the thermosetting reaction, and in the subsequent heating stage, the heating temperature is 200 to 250 ° C, preferably 220 to 240 ° C.
The heating temperature is the temperature of the ink layer, but it is difficult to measure. Therefore, the temperature around the ink layer that can be identified with each other, or when the heating means is in contact with the ink layer, It can be regarded as temperature. Specifically, when the heating means is an oven, it is the temperature inside the oven, and when it is a hot plate, it is the temperature of the heating section.
Moreover, it is preferable that heating time is 10 to 120 minutes, More preferably, it is 40 to 100 minutes. By setting the heating temperature and the heating time within the above ranges, the curing is sufficiently completed, and it is possible to suppress degassing in subsequent processes such as rib / column formation, ITO film formation, liquid crystal injection, and generation of cracks. it can.

  When the ink layer is heated at a temperature lower than the thermal decomposition temperature of components (dispersant and coloring material) that do not contribute to the thermosetting reaction, the thermosetting reaction proceeds, and the thermosetting binder in the ink layer has a network structure. By forming, oxygen inhibition occurs with respect to components that do not contribute to the thermosetting reaction in the ink layer (network structure). For this reason, even if the ink layer is subsequently heated at a high temperature of 200 to 250 ° C., it is considered that components (dispersant and coloring material) that do not contribute to the thermosetting reaction in the ink layer are less likely to generate decomposition products. It is done. This makes it difficult for the pixel to yellow due to oxidation of the resin, and suppresses a decrease in luminance after curing.

  By drying and heating the ink layer as described above, the ink layer is cured and pixels are formed.

  Next, the protective film 8 is formed on the transparent substrate on the side where the pixels 34R, 34G, and 34B are formed (FIG. 3E). The protective film can be formed by a method such as spin coater, roll coater, spray, printing, etc. using a transparent resin composition. For example, it is preferably formed by applying a spin coater within a range of 500 to 1500 revolutions / minute and then curing by exposure and / or heating.

The transparent electrode on the protective film is made of indium tin oxide (ITO), zinc oxide (ZnO), tin oxide (SnO), etc., and alloys thereof, such as sputtering, vacuum deposition, CVD, etc. It is formed by a general method, and can be formed into a predetermined pattern by etching using a photoresist or using a jig as necessary.
In others, it can manufacture using the method similar to the method of forming a normal color filter.

II. Color filter The color filter of the present invention includes at least a transparent substrate and pixels provided on the transparent substrate, and the pixels include a thermosetting binder in a predetermined region on the transparent substrate. Is selectively applied by an ink jet method to form an ink layer, and then the ink layer is dried, and then at a temperature lower than the thermal decomposition temperature of a component that does not contribute to the thermosetting reaction in the ink jet ink composition. The ink layer can be cured and formed by heating and then heating at a temperature of 200 to 250 ° C.

In the present invention, when the ink layer is heated, first, a component that does not contribute to the thermosetting reaction is first heated at a temperature lower than the thermal decomposition temperature of the component that does not contribute to the thermosetting reaction in the inkjet ink composition. The thermosetting reaction can proceed without causing thermal decomposition. Thereby, the thermosetting binder in the ink layer forms a network structure. As the thermosetting reaction proceeds and a network structure is formed, oxygen inhibition occurs for components that do not contribute to the thermosetting reaction in the ink layer (network structure). For this reason, it is considered that components that do not contribute to the thermosetting reaction are hardly decomposed even if the ink layer is subsequently heated at a high temperature of 200 to 250 ° C. In addition, it is considered that decomposition products generated by heating the ink layer at a high temperature of 200 to 250 ° C. are less likely to volatilize due to the formation of the network structure.
Therefore, according to the present invention, the thermal decomposition of components that do not contribute to the thermosetting reaction in the ink layer due to heating of the ink layer can be suppressed, the yellowing due to the oxidation of the resin hardly occurs, and after the curing It is possible to provide a color filter capable of suppressing a decrease in luminance. In addition, since thermal decomposition of components that do not contribute to the thermosetting reaction in the ink layer is suppressed and the amount of decomposition products contained in the pixel can be reduced, in the subsequent process, particularly on the pixel or on the pixel. When a protective film is formed on the protective film, generation of degas due to the decomposition product can be suppressed even when heated in the step of forming indium tin oxide (ITO) on the protective film.

  FIG. 2 is a longitudinal sectional view showing an example (color filter 103) of the color filter of the present invention. The color filter 103 covers the light shielding part 6 formed in a predetermined pattern on the transparent substrate 5, the pixels 7 (7R, 7G, 7B) formed in a predetermined pattern on the light shielding part, and the pixels. The formed protective film 8 is provided. A transparent electrode film 9 for driving liquid crystal is formed on the protective film 8. The protective film 8 may not be provided. An alignment film 10 is formed on the innermost surface of the color filter 103, in this case on the transparent electrode.

The columnar spacer 12 is a shape of a convex spacer, and is formed at predetermined multiple locations (four locations in FIG. 2) on the transparent electrode 9 in accordance with the region (non-display region) where the light shielding portion 6 is formed. Yes. The columnar spacer 12 is formed on the transparent electrode 9, the pixel 7, or the protective film 8. In the color filter 103, columnar spacers are formed in a sea-island shape on the protective film 8 via the transparent electrode film 9, but the protective film 8 and the columnar spacer 12 are integrally formed and covered thereover. A transparent electrode film 9 may be formed. In the case where the color filter does not include a light shielding portion, a columnar spacer can be formed in a region where pixels are not formed.
Hereinafter, each component will be described.

(Transparent substrate)
The transparent substrate 5 is not particularly limited as long as it is conventionally used for a color filter. For example, the transparent substrate 5 is not transparent, such as quartz glass, Pyrex (registered trademark) glass, or synthetic quartz plate. A transparent material having flexibility such as a rigid material, a transparent resin film, an optical resin plate, or the like can be used. Among them, Corning 7059 glass is a material having a small coefficient of thermal expansion, excellent dimensional stability and workability in high-temperature heat treatment, and is an alkali-free glass containing no alkali component in the active matrix. Suitable for color filters for color liquid crystal display devices. In the present invention, a transparent substrate is usually used, but a reflective substrate or a white colored substrate can also be used. Moreover, you may use the board | substrate which surface-treated for the purpose of alkali elution prevention, gas-barrier provision, and other purposes as needed.

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

(Shading part)
The light shielding portion 6 is provided so as to surround the pixels 7R, 7G, and 7B and the outside of the pixel formation region in order to improve the contrast of the display image. The light shielding portion 6 may be a metal thin film such as chromium by sputtering, vacuum deposition, or the like. Alternatively, the light shielding part 6 may be a resin layer in which light shielding particles such as carbon fine particles, metal oxides, inorganic pigments, and organic pigments are contained in a resin binder. In the case of a resin layer containing light-shielding particles, there are a method of patterning by development using a photosensitive resist and a method of patterning using an inkjet ink containing light-shielding particles.
The thickness of the light shielding part is about 1000 to 2000 mm in the case of a metal thin film, and about 0.5 to 2.5 μm in the case of a light shielding resin layer.

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

(Spacer)
A plurality of convex spacers are provided in a non-display area on the substrate in order to maintain a cell gap when the color filter 103 is bonded to a liquid crystal driving side substrate such as a TFT array substrate. The shape and size of the convex spacer are not particularly limited as long as it can be selectively provided in a non-display region on the substrate and can maintain a predetermined cell gap over the entire substrate. When the columnar spacer 12 as shown in the figure is formed as a convex spacer, it has a certain height in the range of about 2 μm to 10 μm, and the protruding height (pattern thickness) is required for the liquid crystal layer. It can set suitably from thickness etc. Moreover, the thickness of the columnar spacer 12 can be appropriately set within a range of about 5 μm to 20 μm. Further, the formation density (density) of the columnar spacers 12 can be appropriately set in consideration of the thickness unevenness of the liquid crystal layer, the aperture ratio, the shape and material of the columnar spacers, for example, red, green and blue Necessary and sufficient spacer function is expressed at a ratio of one for each pixel. The shape of such a columnar spacer may be a columnar shape, and may be, for example, a columnar shape, a prismatic shape, a truncated cone shape, or the like.

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

(Transparent electrode film)
The transparent electrode film 9 can be formed using indium tin oxide (ITO), zinc oxide (ZnO), tin oxide (SnO), or an alloy thereof. The thickness of the transparent electrode can be about 20 to 500 nm, preferably about 80 to 300 nm.

(Alignment film)
The alignment film 10 is provided on the inner surface side of the color filter so as to cover the display portion including the colored layer 7 and the non-display portion including the light shielding layer 6 and the columnar spacer 12. The alignment film can be formed by applying a coating solution containing a resin such as a polyimide resin by a known method such as spin coating, drying, curing with heat or light as necessary, and then rubbing.

(Other layers)
Other members usually formed on the color filter may be further included. Other members can be formed by a usual method using those usually used for color filters.

III. Liquid crystal display device A liquid crystal display device according to the present invention comprises a display side substrate and a liquid crystal driving side substrate facing each other and encapsulating liquid crystal therebetween, and the display side substrate is used for manufacturing the color filter according to the present invention. A color filter manufactured by the method.
The liquid crystal display device of the present invention can be a high quality liquid crystal display device by using the color filter.

When the color filter 103 (display side substrate) obtained as described above and the TFT array substrate (liquid crystal drive side substrate) are opposed to each other and the inner peripheral side peripheral portions of both the substrates are joined with a sealant, the both substrates are separated by a predetermined distance. Bonding is performed with the cell gap maintained. An active matrix color liquid crystal display device belonging to the liquid crystal display device of the present invention can be obtained by filling the gap between the substrates with liquid crystal and sealing it.
Since other configurations and manufacturing methods in the liquid crystal display device can use commonly used configurations and methods, description thereof is omitted here.

  The liquid crystal display device of the present invention is not particularly limited as long as it has the above-described color filter, and may be a known liquid crystal display device. Specific examples include IPS (In-Plane Switching) type, STN (Super Twisted Nematic) type, TN (Twisted Nematic) type, ferroelectric type, antiferroelectric type, MVA mode type, and the like.

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

  Hereinafter, the present invention will be described more specifically with reference to examples. These descriptions do not limit the present invention.

(1) Preparation of pigment dispersion A pigment, a dispersant, and a solvent are mixed in the following ratio, and 500 parts by weight of zirconia beads having a diameter of 0.3 mm are added and dispersed for 4 hours using a paint shaker (manufactured by Asada Tekko Co., Ltd.). A blue pigment dispersion was prepared.

[Composition of pigment dispersion]
・ C. I. Pigment Blue 15: 6 (manufactured by Dainichi Seika Kogyo Co., Ltd.): 8.03 parts by weight C.I. I. Pigment Violet 23 (manufactured by Dainichi Seika Kogyo Co., Ltd.): 0.21 part by weight Dispersant (Ajisper Pb821 (manufactured by Ajinomoto Fine Techno Co., Ltd.)) : 4.12 parts by weight · BCA (diethylene glycol monobutyl ether acetate): 49 parts by weight

(2) Production Example 1: Synthesis of Binder Epoxy Compound Solvent diethylene glycol monobutyl ether acetate containing no hydroxyl group in a four-necked flask equipped with a thermometer, a reflux condenser, a stirrer, and a dropping funnel according to the blending ratio shown in Table 1. 40.7 parts by weight (also called butyl carbitol acetate, hereinafter may be referred to as BCA) was charged, heated with stirring, and heated to 140 ° C. Next, 54.7 parts by weight of a mixture (dropping component) of a monomer having a composition described in Table 1 and a polymerization initiator at 140 ° C. was dropped at a constant rate from a dropping funnel over 2 hours. After completion of the dropwise addition, the temperature was lowered to 110 ° C., 4.6 parts by weight of a mixture of polymerization initiator and solvent-free diethylene glycol monobutyl ether acetate (BCA) (additional catalyst component) was added, and the temperature at 110 ° C. was maintained for 2 hours. By the way, by terminating the reaction, a binder epoxy compound having the characteristics shown in Table 1 was obtained.

＊１）表中の略号は以下の通りである。
ＧＭＡ：グリシジルメタクリレート
ＭＭＡ：メチルメタクリレート
パーブチルＯ：ｔ−ブチルパーオキシ２−エチルヘキサノエート（日本油脂（株）製商品名）
＊２）重量平均分子量：ゲル浸透クロマトグラフィーによるポリスチレン換算の値である。

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

(3) Preparation of Binder A Teflon (registered trademark) -coated rotor was placed in a sample bottle and placed on a magnetic stirrer. In this sample bottle, add a binder-type epoxy compound, polyfunctional epoxy resin, etc. according to the following ratio, stir and dissolve thoroughly at room temperature, then add a diluting solvent to adjust the viscosity, stir and dissolve, Was filtered to obtain a binder composition.

[Binder composition]
Binder epoxy compound of Production Example 1 (solid content 30 wt% in solvent BCA): 2.87 parts by weight Polyfunctional epoxy resin (trade name Epicoat 154, manufactured by Japan Epoxy Resin): 1.91 parts by weight Neo Pentyl glycol glycidyl ether: 0.96 parts by weight Trimellitic acid: 1.91 parts by weight BCA (diethylene glycol monobutyl ether acetate): 17 parts by weight

(4) Preparation of inkjet ink In the blending ratio shown in Table 2, the prepared blue pigment dispersion, the binder composition, and the low boiling point solvent (ethyl ethoxypropionate (EEP)) were sufficiently mixed to prepare the inkjet ink. Prepared.

  The following evaluation was performed about the Example and comparative example which are shown below.

Example 1
A light shielding part pattern having a line width of 20 μm and a film thickness of 2.0 μm was formed on a glass substrate (manufactured by Asahi Glass Co., Ltd.) having a thickness of 0.7 mm by a photolithographic method using the light shielding part forming composition. .
A substrate having a contact angle (θ) of diethylene glycol monobutyl ether acetate at the upper part of the light shielding part of 50 ° was produced using an atmospheric pressure plasma apparatus.
The ink-jet ink was attached to the pixel formation portion partitioned by the light-shielding portion of the substrate by an ink-jet method to form an ink layer.
Then, it dried under reduced pressure at 20 Pa for 240 seconds on a 23 degreeC hotplate, and also prebaked for 60 minutes on the 90 degreeC hotplate. Thereafter, heating was performed at 180 ° C. for 10 minutes in a clean oven, followed by heating at 240 ° C. for 30 minutes to form a pixel pattern on the substrate.

(Comparative Example 1)
In Example 1, a pixel pattern was formed on the substrate in the same manner as in Example 1 except that the prebaking was followed by heating at 240 ° C. for 40 minutes.

(1) Measurement of thermal weight reduction amount In Example 1 and Comparative Example 1, the thermal weight reduction amount of the ink layer was measured using a thermal weight reduction measurement device (Rigaku Corporation, TG8110 (trade name)).
Specifically, in Example 1 above, the temperature was increased at a rate of temperature increase of 10 ° C./min from the start of heating after pre-baking, held at 180 ° C. for 10 minutes, and then further increased at a rate of temperature increase of 10 ° C./min. The weight change of the ink layer was measured at the initial value, after 70 minutes, and after 100 minutes under the condition of maintaining at 240 ° C. for 100 minutes, and the weight loss was calculated. Further, in Comparative Example 1, the ink layer weight change was the initial value, after 70 minutes, and 100 under the condition that the temperature was increased at a rate of temperature increase of 10 ° C./min from the start of heating after pre-baking and maintained at 240 ° C. for 100 minutes. Measurements were taken after minutes and the weight loss was calculated. The results are shown in Table 3.

(Example 2)
A light shielding part pattern having a line width of 20 μm and a film thickness of 2.0 μm was formed on a glass substrate (manufactured by Asahi Glass Co., Ltd.) having a thickness of 0.7 mm by a photolithographic method using the light shielding part forming composition. .
A substrate having a contact angle (θ) of diethylene glycol monobutyl ether acetate at the upper part of the light shielding part of 50 ° was produced using an atmospheric pressure plasma apparatus.
The inkjet ink was adhered to the pixel forming portion partitioned by the light shielding portion of the substrate by an inkjet method.
Then, it dried under reduced pressure at 20 Pa for 240 seconds on a 23 degreeC hotplate, and also prebaked for 60 minutes on the 90 degreeC hotplate. Thereafter, heating was performed at 130 ° C. for 10 minutes in a clean oven, and then heating was performed at 230 ° C. for 94 minutes to form a pixel pattern on the substrate.

(Example 3)
In Example 2, a pixel pattern was formed on the substrate in the same manner as in Example 2 except that after prebaking, heating was performed at 140 ° C. for 10 minutes and then heating was performed at 230 ° C. for 94 minutes.

Example 4
In Example 2, a pixel pattern was formed on the substrate in the same manner as in Example 2 except that after pre-baking, heating was performed at 150 ° C. for 10 minutes and then heating was performed at 230 ° C. for 94 minutes.

(Example 5)
In Example 2, a pixel pattern was formed on the substrate in the same manner as in Example 2 except that the prebaking was followed by heating at 160 ° C. for 10 minutes and then at 230 ° C. for 94 minutes.

(Example 6)
In Example 2, a pixel pattern was formed on the substrate in the same manner as in Example 2 except that after pre-baking, the sample was heated at 190 ° C. for 10 minutes and then heated at 230 ° C. for 94 minutes.

(Example 7)
In Example 2, a pixel pattern was formed on the substrate in the same manner as in Example 2 except that after prebaking, heating was performed at 130 ° C. for 30 minutes and then heating was performed at 230 ° C. for 94 minutes.

(Example 8)
In Example 7, a pixel pattern was formed on the substrate in the same manner as in Example 7 except that after pre-baking, heating was performed at 140 ° C. for 30 minutes and then heating was performed at 230 ° C. for 94 minutes.

Example 9
In Example 7, a pixel pattern was formed on the substrate in the same manner as in Example 7 except that after pre-baking, heating was performed at 150 ° C. for 30 minutes and then heating was performed at 230 ° C. for 94 minutes.

(Example 10)
In Example 7, a pixel pattern was formed on the substrate in the same manner as in Example 7 except that heating was performed at 160 ° C. for 30 minutes after pre-baking and then heating was performed at 230 ° C. for 94 minutes.

(Comparative Example 2)
In Example 2, a pixel pattern was formed on the substrate in the same manner as in Example 2 except that after pre-baking, heating was performed at 120 ° C. for 10 minutes and then heating was performed at 230 ° C. for 94 minutes.

(Comparative Example 3)
In Example 2, a pixel pattern was formed on the substrate in the same manner as in Example 2 except that prebaking was followed by heating at 230 ° C. for 104 minutes.

(2) Chromaticity coordinates (x, y, luminance Y)
For the pixels obtained in Examples 2 to 10 and Comparative Examples 2 and 3, using a microscope spectrometer (OSP-SP200, manufactured by Olympus Corporation), the color when the chromaticity y is fixed at 0.106 The degree x and the luminance Y were calculated. The results are shown in Table 4.

(Summary of results)
From Table 3 above, Example 1 heated at 180 ° C. for 10 minutes after pre-baking and then heated at 240 ° C. for 30 minutes is compared with Comparative Example 1 heated at 240 ° C. for 40 minutes (conventional post-baking conditions). Thus, the amount of thermal weight loss is small, which indicates that the amount of degas is small. Further, when heating at 180 ° C., a thermosetting reaction proceeds to form a network structure, so that oxygen inhibition occurs with respect to the dispersant in the pixel (network structure). For this reason, it is considered that, even when the pixel is subsequently heated at a high temperature of 240 ° C., the dispersant becomes difficult to decompose, and the thermal weight loss is reduced.
In addition, from Table 4 above, Example 2 was heated (heating 1) at a temperature lower than the thermal decomposition temperature of the component (dispersant) that does not contribute to the thermosetting reaction, and then heated at 230 ° C. for 94 minutes (heating 2). 10, the brightness was higher than that of Comparative Example 3 heated at 230 ° C. for 104 minutes (conventional post-baking conditions). In particular, when the heating temperature of heating 1 was 150 ° C., the luminance showed the maximum value in both the heating time of 10 minutes and 30 minutes (see Examples 4 and 9). Further, the heating time of heating 1 was higher at 30 minutes than at 10 minutes, and the luminance at the same heating temperature was higher at any temperature. Moreover, the brightness of Comparative Example 2 in which the heating temperature of Heating 1 is lower than the lower limit value was as low as 12.796.

DESCRIPTION OF SYMBOLS 1 Color filter 2 Electrode substrate 3 Gap part 4 Sealing material 5 Transparent substrate 6 Light-shielding part 7 (7R, 7G, 7B) Pixel 8 Protective film 9 Transparent electrode film 10 Orientation film 11 Pearl 12 Columnar spacer 20 Transparent substrate 21 Ink application range 22 Undried portion 23 Dry portion (drying completed portion)
DESCRIPTION OF SYMBOLS 31 Pixel formation area 32 Inkjet head 33 Ink layer 34 Pixel part 101,102 Color liquid crystal display device 103 Color filter

Claims (5)

(I) a step of selectively applying an inkjet ink composition containing a thermosetting binder to a predetermined region on the transparent substrate by an inkjet method to form an ink layer; and (ii) drying the ink layer; Next, the ink layer is heated at a temperature lower than the thermal decomposition temperature of the component that does not contribute to the thermosetting reaction in the inkjet ink composition, and then heated at a temperature of 200 to 250 ° C. The manufacturing method of a color filter including the process of forming.   The method for producing a color filter according to claim 1, wherein the components that do not contribute to the thermosetting reaction are a dispersant and a coloring material.   The method for producing a color filter according to claim 2, wherein the dispersant contains a polyallylamine derivative.   The manufacturing method of the color filter as described in any one of Claims 1 thru | or 3 whose temperature lower than the thermal decomposition temperature of the component which does not contribute to the said thermosetting reaction is 130-190 degreeC.   The method for producing a color filter according to any one of claims 1 to 4, wherein the drying is drying under reduced pressure.

Images