JPH085816A - Color filter - Google Patents

Abstract

PURPOSE:To obtain a color filter having high reliability at higher production yield without causing peeling of a black matrix even in the succeeding processes of the production of the color filter. CONSTITUTION:This color filter consists of a light-transmitting substrate and an adhesion layer comprising a coupling agent and a black matrix having a light-shielding agent dispersed in a resin formed in this order on the substrate. The concentration of alkali metals or alkaline earth metals in the black matrix shows the relation of 0.5<A/B<10, wherein A is the average concn. of metals from the interface with the adhesion layer to 100nm depth, and (B) is the average concn. from the 100nm depth to the surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter used for a liquid crystal display device or the like, and more specifically, a color filter having a highly reliable black matrix which does not cause film peeling in the subsequent steps. Regarding

[0002]

2. Description of the Related Art Generally, a color filter for a liquid crystal display device is composed of a large number of picture elements, each of which is a pixel of three primary colors of red, green and blue formed on a light transmissive substrate. Between each pixel, a light-shielding region having a constant width (generally referred to as black on the screen, which is referred to as a black matrix) is provided to increase display contrast.

A conventional color filter utilizes a black matrix prepared by photolithography in advance, and is often formed of a metal thin film having a fine pattern. The metals used for the black matrix include Cr, Ni, Al and the like, and as a forming method thereof, a vacuum thin film forming method such as a sputtering method or a vacuum evaporation method is widely used. Next, in order to form a fine pattern, a photoresist pattern is usually formed by a photolithography method, and then the metal thin film is etched using this resist pattern as an etching mask. By this step, a fine pattern of the metal thin film that matches the fine pattern of the photoresist can be formed.

As a method of forming pixels, a method of dyeing a dyeable medium formed by using a photolithography method, a method of using a photosensitive pigment dispersion composition, and a non-photosensitive pigment dispersion composition are used. In addition to the etching method, the electrodeposition method using a patterned electrode, and the like, there is a method of forming a colored portion by a printing method or an inkjet method as a low-cost manufacturing method.

[0005]

However, the black matrix formed of the metal thin film has a high manufacturing cost in the step of forming the metal thin film, which causes the price increase of the color filter itself. Further, since Cr, which is generally used as a metal thin film for the black matrix, has a high reflectance, C is used in a place where the external light is strong.
The light reflected from the r-plane is also strong, and there is a problem that the display quality is significantly impaired, especially when a color filter is incorporated in a transmissive display. That is, in order to obtain a high-contrast image quality with high display quality, high light-shielding property and low reflectance are required. In order to reduce the reflectance of the black matrix, a method of providing a layer such as chromium oxide between Cr and the light transmissive substrate has been proposed, but the manufacturing cost of the black matrix will be further increased and the cost reduction It is not preferable from the point of.

Therefore, for example, a method has been proposed in which a resin colored by a light shielding agent is patterned to form a black matrix and then pixels are formed to manufacture a color filter (Japanese Patent Laid-Open No. 2-239204, etc.). ). However, there is a problem that the adhesiveness between the light-transmissive substrate and the black matrix is deteriorated, and film peeling frequently occurs at the time of patterning the black matrix or in a post-process, particularly a process requiring heat treatment at a high temperature. That is, when a polyimide resin, which requires heat treatment at a high temperature, is used for a pixel, an alignment film, etc., it becomes a serious problem.
Further, when a polyimide resin is used as the resin for the black matrix, in addition to a decrease in adhesiveness, imidization is inhibited, so that sufficient film strength cannot be obtained and film peeling occurs more frequently. there were. In addition to the black matrix, a line width 5 such as an alignment mark for forming a pixel, an alignment mark for assembling a liquid crystal display panel, a vernier pattern, etc. is formed on the light transmissive substrate.
A fine pattern of ˜200 μm is required, and it is preferable to form the pattern simultaneously with a resin colored with a light-shielding agent when the black matrix is formed. However, these fine patterns also have a problem that film peeling occurs similarly to the black matrix.

As a result of diligent investigations by the present inventors regarding the causes of the decrease in adhesiveness and film peeling, it has been found that the cause is a trace amount of alkali metal or alkaline earth metal on the light transmissive substrate. This alkali metal or alkaline earth metal is caused by poor cleaning of the substrate, the substance contained in the substrate cleaning liquid is redeposited on the light transmissive substrate, or the substance originally contained in the light transmissive substrate. Is.

The present invention was devised in view of the drawbacks of such a technique, and an object thereof is to provide a reliable black matrix in which film peeling does not occur in a subsequent process.

[0009]

The object of the present invention is as follows.
It can be achieved by the following color filters. That is,
In a color filter in which an adhesive layer made of a coupling agent and a black matrix in which a light-shielding agent is dispersed in a resin are laminated in this order on a light-transmissive substrate, the concentration of alkali metal or alkaline earth metal in the black matrix However, the average concentration A from the adhesive layer to a depth of 100 nm,
Assuming the average concentration B from the depth of 100 nm to the surface,
The color filter is characterized in that 0.5 <A / B <10. The details will be described below.

First, as the light-transmitting substrate used in the present invention, borosilicate glass, inorganic glass such as soda lime glass whose surface is coated with silica, or an organic plastic film or sheet is used.

The light transmissive substrate is contaminated by fingerprints, sweat, oil and other organic contaminants, and fragments such as cuts and particles when cut. Therefore, these light-transmissive substrates are usually washed and used. First, coarse particles are removed by brush cleaning, then immersed in a surfactant or the like, ultrasonic waves are applied, and then washed with water and dried. As a surfactant,
Although various kinds can be used, alkaline ones have particularly strong detergency, and alkali metal salts such as Na and K or alkaline earth metal salts are particularly preferably used. Further, those containing a strong alkali such as NaOH and KOH are suitable. After performing such cleaning,
Conventionally, it is washed with water and dried, but it is necessary to shorten the processing time of each process to improve productivity, and it is not possible to perform sufficient water washing, and alkali metals or alkaline earth metals contained in surfactants and strong alkalis Remain on the transparent substrate. In addition, fingerprints, sweat, oils and fats containing alkali metal or alkaline earth metal become sources of contamination of alkali metal or alkaline earth metal in a portion where cleaning is insufficient. Other than this, there are those originally contained in the light transmissive substrate. For example, low alkali borosilicate glass (OA-
2. Nippon Electric Glass Co., Ltd. contains about 0.1% of alkali oxide.

Due to a slight amount of alkali metal or alkaline earth metal contamination on the light transmissive substrate, the concentration of alkali metal or alkaline earth metal near the light transmissive substrate side of the black matrix is significantly increased. Therefore, in the subsequent step, the black matrix is likely to be peeled off or cracked, the reliability of the black matrix is deteriorated, and the yield of the color filter is reduced. In order to prevent the contamination of the black matrix by the alkali metal or alkaline earth metal on the light-transmissive substrate, the present invention provides a light-shielding agent in a resin after laminating an adhesive layer on the light-transmissive substrate. To form a black matrix in which a black matrix is formed. The details will be described below.

The color filter of the present invention is a color filter in which an adhesive layer and a black matrix in which a light-shielding agent is dispersed in a resin are laminated in this order on a light-transmissive substrate, and an alkali metal or alkaline earth in the black matrix is used. The concentration of the group metal is an average concentration A from the adhesive layer to a depth of 100 nm, and an average concentration B from a depth of 100 nm to the surface.
Is 0.5 <A / B <10. If the average density B is increased outside this range, the black matrix may be peeled off in a later step or cracked easily, which is not preferable. It is more preferably 0.5 <A / B <5, and even more preferably 0.5 <A / B <2. The concentration of the alkali metal or alkaline earth metal in the black matrix is quantified by measuring each concentration from the surface of the black matrix to the light transmissive substrate while etching with a secondary ion mass spectrometer or the like. it can.

The adhesive layer is required to withstand heat treatment in a later step, and preferably has at least heat resistance equal to or higher than that of the black matrix, and more preferably 250 ° C. or higher. The heat resistance of 250 ° C. or higher means that the weight loss rate due to thermal decomposition or the like is 10% or less in the heat treatment in the air of 250 ° C. for 30 minutes. Three
It is more preferable to have a heat resistance of 00 ° C. or higher. Also,
It is desirable that it is transparent and has no coloration such as discoloration. In the air,
In the heat treatment at 250 ° C. for 30 minutes, preferably the color difference d
Eab * is 3 or less, more preferably 1 or less, still more preferably 0.5 or less. As the adhesive layer having such properties, various coupling agents can be used, but titanium coupling agents, aluminum coupling agents, zirconium coupling agents, iron coupling agents, zircoaluminate coupling agents can be used. Particularly preferred are silane coupling agents. Any one of these may be used, or a mixture thereof may be used. Specifically, a product obtained by reacting acetylacetone with an organometallic compound shown below can be used. Examples of the organometallic compound include tributoxytitanium, tributoxyaluminum, tetrabutoxyzirconium, tributoxyiron and the like.

Other titanium coupling agents include isopropyltri (N-ethylaminoethylamino) titanate, isopropyltriisostearoyl titanate, titanium di (dioctylproposphate) oxyacetate, tetraisopropyldi (dioctyl). Phosphite) titanate, neoalkoxytri (p-N- (β-aminoethyl) aminophenyl) titanate, isopropyltriisostearyl titanate,
Isopropyltridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate titanate, tetraisopropyl bis (dioctyldodecylbenzenesulfonyl titanate, tetra (2,
2-diallyloxymethyl-1-butyl) bis (di-tridecyl) phosphite totanate, isopropyldimethacrylisostearoyl titanate, dicumylphenyloxyacetate titanate and the like.

As the zirconium-based coupling agent,
In addition, neoalkoxy tris neodecanoyl zirconate, neoalkoxy tris (dodecanoyl) benzenesulfonyl zirconate, neoalkoxy tris (ethylenediamino) zirconate, neoalkoxy tris (m-aminophenyl) zirconate, ammonium zirconium carbonate, Zr There are propionates, etc.

Specific examples of the silane coupling agent include γ-aminopropyltriethoxysilane, γ-aminopropylmethyldiethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane and N-β.
(Aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane and the like.

Further, P-containing compounds such as tritolyl phosphate, Cr-containing compounds such as Cr phosphate, amines such as hydroxybenzylamine, cyclic alkylene urea, organic acid metal salts such as Fe (III) naphthenate, etc. is there.

As a method for forming the adhesive layer, these materials for the adhesive layer are dissolved in an appropriate solvent, coated and then dried. As a coating method, a dip coating, a roll coater, a whaler, a spin coating method such as a spinner is preferably used. After that, it is dried by a hot air oven, a hot plate or the like. If necessary, post bake is performed at 200 to 500 ° C.

As the solvent for forming the adhesive layer, alcohols such as ethanol, alkylene glycols such as ethylene glycol, ethers such as tetrahydrofuran, ketones such as methyl ethyl ketone, and amides such as dimethylacetamide are preferable. However, those having a high evaporation rate and those having a low solubility of alkali metals or alkaline earth metals are more preferable. By using such a solvent, the ability to shield the alkali metal or alkaline earth metal on the light-transmissive substrate is enhanced, which is more preferable. Further, it is more preferable to wash with pure water after forming the adhesive layer. Washing is preferably for 10 seconds to 10 minutes.

The thickness of the adhesive layer is required to shield the alkali metal or alkaline earth metal on the light transmissive substrate so as not to contaminate the black matrix, preferably 5 nm or more, more preferably 20 nm or more, More preferably, it is 100 nm or more. Although the upper limit of the film thickness is not particularly limited, it is preferably 2 μm or less, more preferably 1 μm or less, still more preferably 0.5 μm or less, due to the limitation of the coating and drying apparatus.

Next, a black matrix is formed.
As the black matrix, one obtained by dispersing a light-shielding agent in a resin is used, and it is usually patterned into a stripe shape, a lattice shape or the like by using a photolithography method. The resin is not particularly limited, and epoxy-based resin, acrylic-based, polyimide-based resin containing polyamide-imide, urethane-based resin, polyester-based resin, polyvinyl-based resin, gelatin, etc. Although a non-photosensitive material can be used, it is desirable that it has heat resistance of 250 ° C. or higher,
Epoxy resins, acrylic resins, and polyimide resins are preferable. Among these, the polyimide resin having the highest heat resistance is more preferable. In particular, the concentration of alkali metal or alkaline earth metal in the black matrix is 100 nm from the adhesive layer to a depth of 100 nm and an average concentration of 100 nm.
When the average density B from the surface to the surface is 0.5 <A / B
When it is <10, a remarkable effect can be expected and a black matrix without film peeling can be obtained. The concentration of the alkali metal or alkaline earth metal contained in the black matrix is preferably as low as possible, preferably 1000 ppm or less, more preferably 500 ppm or less, further preferably 50 pp.
m or less.

The polyimide resin for the black matrix is not particularly limited, but a polyimide precursor (n containing a structural unit represented by the general formula (1) as a main component is usually used.
= 1 to 2), which is imidized by heating or a suitable catalyst, is preferably used. After applying a black paste in which a light shielding agent is dispersed in these polyimide precursor solutions onto a light transmissive substrate, A black matrix can be formed by drying.

[0024]

Embedded image In the general formula (1), R ¹ is a trivalent or tetravalent organic group having at least 2 carbon atoms. From the viewpoint of heat resistance, R ¹ is preferably a trivalent or tetravalent group containing a cyclic hydrocarbon, an aromatic ring or an aromatic heterocycle, and having 6 to 30 carbon atoms. Examples of R ¹ are phenyl group, biphenyl group, ta-phenyl group, naphthalene group, perylene group, diphenyl ether group, diphenyl sulfone group, diphenylpropane group, benzophenone group, biphenyltrifluoropropane group, cyclobutyl group, cyclopentyl group. Groups and the like, but are not limited thereto.

R ² is a divalent organic group having at least 2 carbon atoms, but from the viewpoint of heat resistance, R ² contains a cyclic hydrocarbon, an aromatic ring or an aromatic heterocycle, and A divalent group having 6 to 30 carbon atoms is preferable. Examples of R ² are phenyl group, biphenyl group, ta-phenyl group, naphthalene group, perylene group, diphenylether group, diphenylsulfone group, diphenylpropane group, benzophenone group, biphenyltrifluoropropane group, diphenylmethane group, dicyclohexyl. Examples include, but are not limited to, methane groups.

The polymer having the structural unit (1) as a main component is
Each of R ¹ and R ² may be composed of one type of these, or may be a copolymer composed of two or more types. Further, in order to improve the adhesiveness with the substrate or the adhesive layer, it is preferable to copolymerize bis (3-aminopropyl) tetramethyldisiloxane having a siloxane structure as a diamine component within a range that does not reduce the heat resistance.

Specific examples of the polymer having the structural unit (1) as a main component include pyromellitic dianhydride, 3,3 ',
4,4'-benzophenone tetracarboxylic dianhydride,
3,3 ′, 4,4′-biphenyltrifluropropanepropanecarboxylic acid dianhydride, 3,3 ′, 4,4′-biphenylsulfonetetracarboxylic acid dianhydride, 2,3,3
One or more carboxylic acid dianhydrides selected from the group consisting of 5-tricarboxycyclopentyl acetic acid dianhydride and the like, paraphenylenediamine, 3,3′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 3, 4'diaminodiphenyl ether, 3,3'-
Polyimide precursor synthesized from at least one diamine selected from the group consisting of diaminodiphenyl sulfone, 4,4′-diaminodiphenyl sulfone, 4,4′-diaminodicyclohexylmethane, 4,4′-diaminodiphenylmethane But is not limited to these. These polyimide precursors are synthesized by a known method, that is, by selectively combining tetracarboxylic dianhydride and diamine and reacting them in a solvent. If necessary, bis (3-aminopropyl) tetramethyldisiloxane or the like may be copolymerized.

Among these, those having a high light absorption at a wavelength in the visible light region are more preferable because the light-shielding property of the black matrix becomes higher. That is, in a polyimide film having a film thickness of 2 μm, the original stimulus Y in the XYZ color system is used.
Is preferably 96 or less, more preferably 90 or less, still more preferably 80 or less. These values can be calculated by measuring the light transmittance spectrum of the polyimide film in visible light having a wavelength of 400 to 700 nm. For example, as the tetracarboxylic dianhydride, the higher the electron withdrawing property of the acid dianhydride residue is, the more preferable it is, a ketone type such as a benzophenone group, an ether type such as a diphenyl ether group, or a phenyl group-containing one. Those having a sulfone group such as a diphenyl sulfone group are preferable. For example, pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, and the like. As the diamine, the stronger the electron donating property of the diamine residue is, the more preferable, and diaminodiphenyl ether having a biphenyl group, p-, p-substituted or m-, p-substituted structure, methylenedianiline and the like are preferable, and 4,4 'or 3 , 4'-diaminodiphenyl ether, paraphenylenediamine and the like.

As the light-shielding agent for the black matrix, carbon black, metal oxide powder such as titanium oxide and iron tetroxide, metal sulfide powder, a mixture of red, blue and green pigments can be used. Among these, carbon black is particularly preferable because it has excellent light-shielding properties. Carbon black is produced by the contact method called Channel Black, Roller Black, Disk Black, Gas Farnest Black, Farnest Method called Oil Farnest Black, and Thermal Black. , Which is produced by a thermal method called acetylene black can be used, and channel black, gas farnest black and oil farnest black are particularly preferable.

In order to improve the light blocking effect of the black matrix, it is preferable to reduce the particle size of the light blocking agent,
In the case of carbon black, the average primary particle size is 5 to 50 nm
Is preferred. The structure of the carbon black powder is such that fine carbon black is aggregated to form secondary particles of carbon black. When the average of the particle diameters is taken as the average secondary particle diameter, it is preferably 6 to 75 nm, more preferably 7-50
nm, and more preferably 8 to 30 nm. If it is larger than this, sufficient light-shielding properties cannot be obtained, which is not preferable. The average secondary particle diameter is determined by observing carbon black with a transmission electron microscope or the like and determining the average particle diameter according to JIS R6002.

Further, in addition to carbon black, a light shielding agent such as titanium black, red, blue or green pigment may be added, but the proportion of the light shielding agent in the light shielding agent is preferably 50% by weight or less, more preferably 40% by weight. % Or less, more preferably 30% by weight or less. If a light-shielding agent other than carbon black is added more than this, the light-shielding pixels are deteriorated, which is not preferable.

Usually, the solvent is preferably an amide-based polar solvent such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide or N, N-dimethylformamide, a lactone-based polar solvent or dimethylsulfoxide. used. The lactone-based polar solvent means an aliphatic cyclic ester compound having 3 to 12 carbon atoms, and as a specific example,
Examples thereof include .beta.-propiolactone, .gamma.-butyrolactone, .gamma.-valerolactone, .delta.-valerolactone, .gamma.-caprolactone and .epsilon.-caprolactone, with .gamma.-butyrolactone being particularly preferred from the viewpoint of solubility of polyamic acid. Among these, it is preferable to use a lactone-based polar solvent having a low solubility of an alkali metal or alkaline earth metal, more preferably a lactone-based polar solvent as a main component, and more preferably a lactone-based polar solvent alone.
Here, a solvent containing a lactone-based polar solvent as a main component means n
In the case of a mixed solvent composed of different types of solvents, (1 / n) × 10
It is said to contain more than 0% by weight. For example, in the case of a two-component solvent, it means that the lactone-based polar solvent is contained by more than 50% by weight, and in the case of the three-component system, the lactone-based polar solvent is contained by more than 33% by weight. Say. When carbon black is used as the light-shielding agent, it is preferable to use a mixed solvent with an amide-based polar solvent in order to enhance the dispersing effect of carbon black. As a solvent other than these, it is more preferable to mix a solvent having a higher evaporation rate such as methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol, and ethyl lactate in an amount of 5 to 30% by weight in all the solvents.

As a method for dispersing the light-shielding agent, a known technique can be used. After mixing the light-shielding agent in a polyimide precursor solution or a solvent, it is dispersed in a dispersing machine such as a ball mill. In the reaction of the polyimide precursor in, the viscosity increase due to the reaction of the light-shielding agent and the polyimide precursor, to prevent gelation, etc., first, after mixing the light-shielding agent in the solvent, after sufficient pre-dispersion, polyimide precursor Is preferably added later. In order to obtain a high light-shielding property, it is preferable to finely disperse the light-shielding agent, the dispersion strength,
The dispersion time and the like are appropriately adjusted. Further, various additives can be added to the black paste for the purpose of improving coatability, leveling property, dispersibility and the like.

Next, an example of a method for forming a black matrix will be shown. First, a black paste in which a light shielding agent such as carbon black is dispersed in a polyimide precursor solution is applied on the adhesive layer. As a coating method, a dip coating, a roll coater, a whaler, a spinner, or the like is preferably used. After that, it is dried in a hot air oven, a hot plate or the like and semi-cured. The semi-cure conditions are slightly different depending on the kind of the polyimide precursor used and the coating amount, but it is generally heating at 100 to 180 ° C. for 1 to 60 minutes. When a non-photosensitive polyimide precursor is used, a photoresist is then applied, prebaked, exposed using an optical mask, and developed. As a developing solution, an inorganic alkaline aqueous solution such as NaOH or KOH or an organic amine aqueous solution such as tetramethylammonium hydroxide is usually used and developed by a dip, shower, paddle method or the like, but contamination of Na or K is prevented. Therefore, it is more preferable to use a high-purity organic amine aqueous solution. Also,
At the same time, necessary patterns such as alignment marks for forming pixels, alignment marks for assembling liquid crystal display elements, and vernier patterns are also formed. Therefore, even for these fine patterns, between the transparent substrate,
It is preferable that an adhesive layer is formed. In this way
After continuous development of the resist and patterning of the black matrix, the resist is peeled off. When a novolac-based resist is used as the stripping solution, ketones such as acetone, cell solves such as ethyl cell solv, cell solv acetates, and the like are used to strip by a dip, shower, or paddle method. After that, it is cured with hot air or a hot plate, but before that, it is washed with pure water to obtain an average concentration A of the alkali metal or alkaline earth metal from the adhesive layer in the black matrix to a depth of 100 nm. Can be reduced, which is preferable.
Washing is preferably for 10 seconds to 10 minutes. A space of about 20 to 200 μm is usually provided between the black matrices, and pixels are formed in this gap in a later process.

As a method of forming the black matrix, other than this, as a low-cost manufacturing method,
There are methods such as a printing method and an inkjet method.

Next, pixels of a plurality of colors are formed. Usually, the pixel color of each pixel is three colors of red, blue, and green, and is colored with a colorant. Usually, the pixel color of each pixel is
There are three colors, red, blue and green, and they are colored with a coloring agent. Usually, before and after forming each pixel, a cleaning process is performed after removing particles and organic contaminants on the light transmissive substrate. The cleaning method is usually performed according to the cleaning process of the light-transmitting substrate. In the cleaning process and the subsequent process such as the pixel forming process, a black matrix and an alignment mark provided as necessary,
In order to prevent film peeling of a fine pattern such as a vernier pattern, the color filter of the present invention has a specific adhesive layer laminated between the light transmissive substrate and the black matrix.

As the colorant used for the pixel, an organic pigment, an inorganic pigment, a dye or the like can be preferably used, and various additives such as an ultraviolet absorber, a dispersant and a leveling agent may be added. . Organic pigments include phthalocyanine-based, azileke-based, condensed azo-based, quinacridone-based,
Anthraquinone type, perylene type, perinone type and the like are preferably used. Further, as the resin used for the pixel,
Epoxy resin, acrylic resin, polyimide resin, urethane resin, polyester resin, polyvinyl resin,
A photosensitive or non-photosensitive material such as animal protein resin capable of being dyed such as gelatin can be used, and it is preferable to disperse or dissolve a colorant in these resins to color the material. As the photosensitive resin, there are types such as photodecomposition type resin, photocrosslinking type photosensitive resin, and photopolymerization type resin.
A photosensitive composition containing a monomer, an oligomer, or a polymer having an ethylenically unsaturated bond and an initiator that generates a radical by ultraviolet rays as a main component, a photosensitive polyamic acid solution, or the like is preferably used.

As a method for dispersing or dissolving the colorant, a known technique can be used. The colorant is mixed with a solvent and dispersed in a dispersing machine such as a ball mill or dissolved by a stirring device. As a coating method, a dip coating, a roll coating method, a whaler, a spin coating method such as a spinner is preferably used. Among them, the spin coating method such as dip coating, whaler, and spinner is particularly preferable because the coating amount of the pixel forming solution is made uniform on the substrate during coating, and thus the film thickness of pixels is excellent.

Thereafter, by drying with hot air, the first colored layer is formed over the entire surface of the black matrix. Since a color filter is usually composed of pixels of a plurality of colors, unnecessary portions are removed by photolithography to form a desired first color pixel pattern. The unnecessary portion is, for example, a pixel portion to be formed in a later process or a peripheral portion of the light transmissive substrate other than the pixel. When the colored layer has photosensitivity, exposure is performed using an optical mask, and unnecessary portions are removed by development to form a pixel pattern. When the colored layer is non-photosensitive, a resist is applied, exposed by using an optical mask, and developed, and then the patterned resist is used as a mask, and unnecessary portions are removed by an etching method. The resist is peeled off to form a pixel pattern.

This is repeated only for pixels of required colors to form pixels of a plurality of colors to manufacture a color filter. After this, if necessary, a top coat layer, IT
The O transparent electrode, patterning, and the like can be performed by a known method as necessary.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited thereto.

[0042]

Example <Production of polyimide precursor solution for black matrix> 147 g of 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride was charged together with 772 g of N-methyl-2-pyrrolidone to prepare 4,4'- Diaminodiphenyl ether 95.
10 g and 6.20 g of bis (3-aminopropyl) tetramethyldisiloxane were added and reacted at 60 ° C. for 3 hours to obtain a polyimide precursor solution having a viscosity of 600 poise (25 ° C.).

This was coated on a non-alkali glass (OA-2, manufactured by Nippon Electric Glass Co., Ltd.) substrate with a spinner so that the film thickness would be 2 μm, dried at 80 ° C. for 10 minutes, and dried at 120 ° C. for 20 minutes. It was semi-cured for 30 minutes and cured at 300 ° C. for 30 minutes. The original stimulation Y of this polyimide film was 95.

<Production of Polyimide Precursor Solution for Pixel>
147 g of 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride was charged together with 772 g of N-methyl-2-pyrrolidone to prepare 3,3'-diaminodiphenyl sulfone 49.6.
54.5 g of g, 4,4'-diaminodiphenylmethane and 6.20 g of bis (3-aminopropyl) tetramethyldisiloxane were added and reacted at 60 ° C for 3 hours to obtain a polyimide precursor solution having a viscosity of 120 poise (25 ° C). Got

Example 1 First, a non-alkali glass (OA-2, manufactured by Nippon Electric Glass Co., Ltd.) was placed in an alkaline cleaning solution (DIPOSH-A, manufactured by Environmental Science Center Co., Ltd.) at a concentration of 2% by weight at 40 ° C. After immersion cleaning for 3 minutes, it was washed with pure water for 2 minutes and dried at 90 ° C. for 5 minutes.

Next, an adhesive layer was laminated. The following tributoxybutoxytitanate solution was applied by a spinner so that the finished film thickness would be 0.02 μm, dried at 90 ° C. for 10 minutes, and then heat-treated at 250 ° C. for 30 minutes.
To examine the heat resistance of this adhesive layer, 250 ° C 30
After heat treatment for minutes, the weight change due to decomposition was 1% or less. The color difference dEab * at this time was 0.1 or less (using a C light source).

Tributoxytitanate 8 g Ethyl acetoacetate 6 g Toluene 1000 g After this, a black matrix was laminated. First, use a homogenizer to prepare a solution having the following composition at 7000rp
After dispersing at m 2 for 30 minutes, the glass beads were filtered and removed.

Carbon black (average primary particle size 32 nm, average secondary particle size 60 nm, farnested black) 4 g N-methylpyrrolidone 30 g γ-butyrolactone 42 g Glass beads 90 g Thereto was added 24 g of the above black matrix polyimide precursor solution. A black paste was prepared by adding and mixing. A black paste was applied on a glass substrate with a spinner so that the finished film thickness was 1 μm, and semi-cured at 120 ° C. for 20 minutes. After this, a positive resist (Shipley "Microposi
t "RC100 30cp) was applied with a spinner and dried at 80 ° C. for 20 minutes. Exposure was performed through a photomask using an exposure machine PLA-501F manufactured by Canon Inc., and an alkali developing solution (N
The positive resist was developed and the polyimide precursor was etched at the same time with MD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd., and then the positive resist was peeled off with methylcellosolve acetate. Furthermore, it was cured at 300 ° C. for 30 minutes. Thus, a grid-like black matrix having a thickness of 1.0 μm and a width of about 40 μm was provided. At the same time, width of about 20 μm
A fine pattern such as a pixel forming alignment mark and a vernier pattern having a width of about 10 μm were also patterned.

Next, as red, green and blue pigments, Color
Dianthraquinone pigment shown by Index No.65300 Pigment Red 177, Color Index No.74265 Pigment Green 3
Phthalocyanine green pigment shown by 6 Color Inde
x No. 74160 Pigment Blue 15-4 was prepared. The above pigments were mixed and dispersed in a pixel polyimide precursor solution to obtain three kinds of pastes of red, green and blue. First, the substrate was washed with pure water and dried. Then, the green paste was applied to the surface of the light-transmissive glass substrate on which the black matrix was formed, and dried with hot air at 80 ° C. for 10 minutes. After this, a positive resist (Shipley "Micropo
sit "RC100 30cp) was applied with a spinner and dried at 80 ° C for 20 minutes. Exposure was performed using a mask, and an alkaline developer (N
MD-3, manufactured by Tokyo Ohka Kogyo Co., Ltd., is used to simultaneously develop a positive resist and etch a polyimide precursor, and then strip the positive resist with methyl cellosolve acetate to form stripes with a width of about 90 μm and a pitch of 300 μm. A green pixel was obtained. Furthermore, it was cured at 300 ° C. for 30 minutes. The thickness of the pixel layer was 1.5 μm. After washing with water, stripe-shaped red and blue pixels were formed in the same manner so that the pixel intervals of the three colors were 10 μm.

The black matrix OD has a wavelength of 55.
A color filter having an excellent light-shielding property of 3.0 at 0 nm was obtained. Further, in the subsequent step, there was no peeling of the black matrix film, and the dimensional accuracy of the black matrix was ± 0.2 μm or less, which was an excellent color filter. Similarly, fine patterns such as pixel forming alignment marks and vernier patterns did not peel off. The average concentration A of Na metal from the adhesive layer in the black matrix to a depth of 100 nm and the average concentration B of Na metal from the depth of 100 nm to the surface were measured by a secondary ion mass spectrometer, and A / B = 2. Met.

Example 2 In the same manner as in Example 1, an adhesive layer was laminated on the washed alkali-free glass. The γ-aminopropyltrimethoxysilane solution shown below was finished with a spinner to a film thickness of 0.1.
It was coated so as to have a thickness of 01 μm, dried at 90 ° C. for 10 minutes, and then heat-treated at 250 ° C. for 30 minutes. To examine the heat resistance of this adhesive layer, it was further heat-treated at 250 ° C. for 30 minutes, but the weight change due to decomposition was 1% or less. The color difference dEab * at this time was 0.1 or less (using a C light source).

Γ-Aminopropyltrimethoxysilane 1 g Isopropyl alcohol 1000 g A black matrix, alignment marks, and vernier patterns were laminated thereon in the same manner as in Example 1. Further, in the same manner as in Example 1, stripe-shaped green, red, and blue pixels having a width of about 90 μm and a pitch of 300 μm were formed so that the pixel intervals of the three colors were 10 μm.

The black matrix OD has a wavelength of 55.
A color filter having an excellent light-shielding property of 3.0 at 0 nm was obtained. Further, in the subsequent step, there was no peeling of the black matrix film, and the dimensional accuracy of the black matrix was ± 0.2 μm or less, which was an excellent color filter. Similarly, fine patterns such as alignment marks for pixel formation and vernier patterns did not peel off.

Average concentration A of Na metal from the adhesive layer in the black matrix to a depth of 100 nm, depth 100 n
When the average concentration B of Na metal from m to the surface was measured by the secondary ion mass spectrometer, A / B = 3.

Comparative Example 1 In the same manner as in Example 1, the alkali-free glass was washed.
A black matrix was laminated in the same manner as in Example 1 without laminating the adhesive layer. Further, in the same manner as in Example 1, stripe-shaped green and red pixels having a width of about 90 μm and a pitch of 300 μm were formed so that the pixel intervals of the three colors were 10 μm. In the cleaning process before the blue pixel forming process, the pixel forming alignment mark was detached, and the blue pixel could not be formed.

The OD of the black matrix in the normal area is
The light-shielding property was excellent at 3.0 at a wavelength of 550 nm, but film peeling occurred at the edges of the black matrix in the green and red pixel formation and each washing step, and pinhole-like defects were formed in places. . This portion is transparent and has no light blocking effect. The dimensional accuracy of the black matrix in the normal portion was excellent at ± 0.2 μm or less, but the film peeling portion was −5 μm, and the required dimensional accuracy was not obtained. Similarly, film peeling occurred in fine patterns such as alignment marks for pixel formation and vernier patterns.

Average concentration A of Na metal in the black matrix from the glass plate side to a depth of 100 nm, depth 10
When the average concentration B of Na metal from 0 nm to the surface was measured by the secondary ion mass spectrometer, A / B = 12.

[0058]

As described above, the color filter of the present invention is improved in the adhesiveness of the black matrix, has no film peeling even in the post-process of manufacturing the color filter, and has an improved yield and a highly reliable color. You can get a filter.

Claims (4)

[Claims] 1. A color filter in which an adhesive layer made of a coupling agent and a black matrix in which a light-shielding agent is dispersed in a resin are laminated in this order on a light-transmissive substrate, wherein an alkali metal or alkali in the black matrix is used. When the concentration of the earth metal is an average concentration A from the adhesive layer to a depth of 100 nm and an average concentration B from the depth of 100 nm to the surface, 0.5 <A / B <10. filter. 2. The color filter according to claim 1, wherein the heat resistance of the adhesive layer is 250 ° C. or higher. 3. The adhesive layer comprises a titanium coupling agent, an aluminum coupling agent, a zirconium coupling agent,
The color filter according to claim 1, comprising at least one coupling agent selected from the group consisting of an iron coupling agent, a zircoaluminate coupling agent, and a silane coupling agent. 4. The color filter according to claim 1, wherein the black matrix is one in which a light shielding agent is dispersed in a polyimide resin.