JPH085819A - Color filter substrate and colored film paste - Google Patents

Abstract

(57) [Summary] [Structure] A color filter substrate in which a colored film of three colors, a protective film, and a transparent conductive film are laminated in this order on a substrate,
At least one of the three-colored colored film and the protective film contains an ionic polymer, and the three-colored colored film and the protective film. , The surface resistance of at least one film is 10 ⁹ Ω /
A color filter substrate having a range of □ to 10 ¹² Ω / □. [Effect] Since the surface resistance of the colored film or the protective film could be reduced without adding particles such as metal oxides, the contrast was reduced due to light scattering,
It is possible to provide a colored film or a protective film with less repellency or uneven coating without deteriorating the coating characteristics.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter substrate used for a liquid crystal display, an image sensor, an image pickup device or the like.

[0002]

2. Description of the Related Art As a colored film capable of forming a color filter substrate having excellent heat resistance and light resistance, a colored film in which a pigment is dispersed in a polyimide polymer is known (for example, JP-A-60-184202). Japanese Patent Laid-Open No. 60-1
84203, JP-A-61-180203). The production of a color filter substrate using a colored paste in which a pigment is dispersed in an organic solvent solution of a polyamic acid, which is a precursor of a polyimide-based polymer, is disclosed in, for example, JP-A-60-247603, according to a photolithography method. As shown in Japanese Patent Laid-Open No. 61-77804, the following steps are performed. Colored paste (for example, green) on a substrate on which a black matrix made of a chromium film, a chromium oxide film, or a resin containing a black dye is formed.
And then dried to form a polyimide precursor colored film. A positive photoresist is applied on the polyimide precursor colored film to form a photoresist film. A mask is placed on the photoresist film, and ultraviolet rays are irradiated using an exposure device. After exposure, the photoresist film and the polyimide precursor colored film are simultaneously etched with a positive photoresist alkaline developer. After etching, the unnecessary photoresist film is removed. After that, the polyimide precursor is converted into polyimide by heat treatment. In this way, after forming a pattern of a one-color polyimide colored film on a substrate, a color paste of another color (for example, red) is applied thereon, and through the same steps,
A two-color polyimide colored coating pattern is formed on the substrate. When this is repeated once again, a pattern of the polyimide colored film of three colors of red, blue and green is obtained. In addition, a protective film may be provided on top of this for the purpose of improving flatness and preventing impurities from eluting into the liquid crystal. Each film of the color filter substrate including the black matrix made of the black dye-containing resin and the protective film is formed by a printing method, a spin coating method, a dipping method, a slit die method, a bar coater method, a blade coater method, a roll coater method, a spray method. Although it is formed by, etc., in order to maintain the production yield of color filter substrate,
It is important to coat each color filter substrate film without defects.

It is unavoidable that the insulating substrate and the film underlying the coating film are peeled off or triboelectrically charged at the time of substrate transport or coating. When the amount of charge increases, dust is attracted and the defects of the coating film are likely to occur, so in the past, ionization air was blown before the coating to eliminate static electricity.
In this method, the effect of static elimination is insufficient, or uneven static elimination occurs, so that the effect of suppressing the occurrence of defects in the coating film is small. The present inventors have examined the relationship between the amount of charge and the occurrence of defects in each film of the color filter substrate, and as a result, the charging of the film that is the base of the coating film not only adsorbs dust, but also repels the coating film. It has been found that this may cause defects. In addition, in the case where charging occurs due to a substrate operation between coating and drying of the film, in-plane uniform charging does not generally occur, and the unevenness of charging sometimes impairs the uniformity of the coating film.

A method is conceivable in which conductivity is imparted to allow the charge to escape in order to reduce the charge. JP-A-1-18561
No. 6, JP-A No. 1-201606, in a configuration in which a transparent conductive film is arranged between a colored film and a substrate, the load of the liquid crystal display driver circuit increases due to a voltage drop due to the colored film in each pixel, and the contrast increases. In order to prevent the decrease, it has been proposed to add a conductive material to the colored film so that the colored film has a conductivity of about 10 ⁸ Ω / □. In addition, JP-A-6
According to Japanese Patent Laid-Open No. 3-165822, a conductive material is used in order to suppress color balance shift due to a difference in voltage drop due to a colored film in each pixel in a configuration in which a transparent conductive film is similarly arranged between a colored film and a substrate. It is proposed that the pastes for the red, green and blue colored films are made uniform by adding to 1.2 × 10 ¹⁴ Ω · cm (1.2 × 10 ¹⁸ Ω / □ when the film thickness is 1 μm). These proposed conductive materials add conductive particles such as metal oxide particles and metal particles, but the addition of particles has the characteristics of the colored film paste, protective film paste and resin black matrix paste. There is a problem in that the coating property is changed and the coating property is deteriorated, and the scattering of light is increased to lower the contrast of the color filter substrate. In addition, these proposals relate to a configuration in which a transparent conductive film is arranged between a colored film and a substrate, and the effect that the charging of the colored film is alleviated by the transparent conductive film serving as a base film of the colored film Therefore, in the case of the structure of laminating the transparent conductive film on the upper surface of the colored film after forming the colored film of the present invention, it is more susceptible to the influence of charging.

[0005]

DISCLOSURE OF THE INVENTION The present inventors have been devised in view of these drawbacks of the prior art. The purpose is to add particles that cause light scattering or deterioration of coating properties. It is an object of the present invention to provide a color filter substrate which is not required and is less susceptible to charging even in a color filter substrate having a structure in which a transparent conductive film is provided on the upper surface of a colored film, and in which coating defects are less likely to occur.

[0006]

The present invention is achieved by the following configurations.

That is, a three-color colored film made of a resin and a coloring material on a substrate, a transparent conductive film, or a three-color colored film made of a resin and a coloring material on a substrate, a protective film made of a resin, and a transparent film. A color filter substrate having conductive films laminated in this order, wherein at least one of the three colored films and the protective film contains an ionic polymer. And a three-color coloring film made of a resin and a coloring material on a substrate, a transparent conductive film, or a three-color coloring film made of a resin and a coloring material on a substrate, a protective film made of a resin, and a transparent conductive film. Are laminated in this order, and at least one of the three colored films and the protective film has a surface resistance of 1 or less.
It is a color filter substrate characterized by being in the range of 0 ⁹ Ω / □ to 10 ¹² Ω / □.

As the substrate of the present invention, soda glass, non-alkali glass such as barium borosilicate glass, aluminum borosilicate glass, and quartz glass, a transparent plastic substrate, a silicon wafer, and a gallium-arsenic wafer are used. The thickness of glass and plastic substrates is typically in the range 0.5 mm to 2 mm. When soda glass is used, it is preferably coated with silicon oxide to prevent the elution of ions from the glass.

The colored film of the present invention comprises a resin and a coloring material. As the resin, gelatin, acrylic, polyvinyl alcohol, polyamide, polyimide, polyamide-imide, etc. can be adopted, but a polyimide referred to as a polyimide-based polymer in the present invention in terms of excellent light resistance, heat resistance and chemical resistance, and Polyamideimide is preferred. As the coloring material, dyes and pigments can be used, but pigments are preferable because they are excellent in light resistance, heat resistance and chemical resistance. The pigment used in the present invention is not particularly limited, but among the pigments, pigments excellent in light resistance, heat resistance and chemical resistance are preferable. Specific examples of typical pigments are shown by color index (CI) numbers. Examples of yellow pigments include Pigment Yellow 20, 24, 83, 86, 93, 94, 109, 11
0, 117, 125, 137, 138, 139, 14
7, 148, 153, 154, 166, 173 and the like. Pigment Orange 1 is an example of an orange pigment.
3, 31, 36, 38, 40, 42, 43, 51, 5
5, 59, 61, 64, 65 and the like. Examples of red pigments are Pigment Red 9, 97, 122, 1
23, 144, 149, 166, 168, 177, 18
0, 192, 215, 216, 224 and the like. An example of a purple pigment is Pigment Violet 1.
9, 23, 29, 32, 33, 36, 37, 38 and the like. Pigment Blue 1 as an example of a blue pigment
5 (15: 3, 15: 4, 15: 6, etc.), 21, 2
2, 60, 64 and the like. Pigment green 7, 10, 36, 47 etc. are mentioned as an example of a green pigment. Examples of black pigments include Pigment Black 7. In the present invention, various pigments can be used without being limited thereto. The pigment may be subjected to surface treatment such as rosin treatment, acidic group treatment, and basic treatment, if necessary.

Since the red, green, and blue color pixels of the color filter used in the liquid crystal display element need to be similar to the chromaticity characteristics of the CRT phosphor, the above pigments are used in the backlight and the liquid crystal display element. To match the light transmission characteristics, several colors are combined and used for toning. For example, red is toned with a red pigment and yellow pigment or orange pigment, green is toned with a green pigment and yellow pigment or orange pigment, and blue is toned with a combination of blue pigment and purple pigment. As the black matrix of the color filter, a black pigment or a mixture of pigments of other colors may be used.

The protective film of the present invention is required to be excellent in transparency, heat resistance, chemical resistance, hardness, leveling of steps, ion blocking property, adhesive strength, etc., and acrylic, polyimide, polyamide-imide, silicone- And polyimide-modified silicone can be preferably used. Above all, it is preferable to use polyimide, polyamide-imide, or polyimide-modified silicone having excellent heat resistance. Heat resistance, chemical resistance, hardness of the colored film,
The protective film is not always necessary when there is no practical problem in the step flatness and the ion blocking property. In addition, a transparent conductive film or a silicon oxide film and a transparent conductive film are generally laminated on the protective film in this order by a vacuum deposition method such as sputtering, and a coating film is not laminated on the protective film. Conductivity is preferably imparted to the protective film for the purpose of reducing the amount of charge in the paste state of the film and preventing dust from adhering to the protective film.

In the color filter substrate of the present invention, a light-shielding film around a pixel called a black matrix is provided between the substrate and a red, green or blue color film formed by mixing a resin with a coloring material, or a red film. , Green and blue can be laminated on the colored films. As the black matrix material, a resin containing a black pigment, a metal chromium film, a chromium oxide film, or the like is used.

Of the three colored films and protective film of the present invention,
It is important that at least one membrane contains an ionic polymer. The inclusion of the ionic polymer enables the reduction of the surface resistance of the colored film or the protective film and the reduction of the charge amount without lowering the contrast and the coating property of the colored film / protective film. It is possible to reduce the occurrence of defects when applying the protective film.

The ionic polymer of the present invention is a ionic group bonded to a hydrophobic polymer as a side chain, main chain or main chain terminal, and includes carboxylic acid, sulfuric acid ester, sulfonic acid,
Anionic polymers having ionic groups such as phosphoric acid esters and cationic polymers having ionic groups such as quaternary ammonium salts can be used. Specific examples of anionic polymers that are preferably used include polyacrylic acid, polymethacrylic acid, ethylene-acrylic acid copolymer, ethylene-
Methacrylic acid copolymer, vinyl alkyl ester-maleic acid copolymer, polyvinyl alcohol sulfate,
Examples thereof include polyethylene sulfonic acid, polystyrene sulfonic acid, polyvinyl phosphoric acid, polymetaphosphoric acid, and salts thereof. Specific examples of suitably used cationic polymers include polyvinylphenyl quaternary ammonium salt, polyvinylamine salt, polyethyleneimine salt, polyvinylpyridine salt, and polyvinylalkylpyridine salt. In order to reduce the resistance value, it is preferable to use a cation-based polymer, while an anion-based polymer is preferable because of its excellent heat resistance as a colored film or a protective film. Among the anionic polymers, polystyrene sulfonic acid and its salts have a heat resistance of 290 ° C. or higher and are particularly preferable. The molecular weight of the ionic polymer is preferably in the range of 500 to 120,000 because the transparency is impaired if it is too large, and the effect of reducing the surface resistance is small if it is too small, preferably in the range of 3000 to 80,000. It is more preferable that it is in the range of 10,000 to 70,000. Ammonium is used as a cation for salt formation,
Although there are lithium, sodium, potassium, zinc, magnesium and the like, it is preferable to use ammonium or lithium because they do not adversely affect the liquid crystal and the semiconductor. Furthermore, ionic polymers should be used in the acid state rather than salt,
It is preferable because it does not adversely affect the liquid crystal and the semiconductor.

The ionic polymer is 0.001% by weight based on the solid component of the paste for forming the target coating film, that is, the weight of the coating film excluding the surfactant and the ionic polymer.
To 20% by weight, preferably 0.01 to 10% by weight. If too much ionic polymer is added, the characteristics of the colored film will change, making it difficult to apply,
The transparency of the colored film may decrease. In addition, hygroscopicity is increased by increasing the amount of ionic polymer added,
When heat resistance, light resistance, chemical resistance, and weather resistance of the colored film is deteriorated, or when a transparent conductive film or a silicon oxide film or a transparent conductive film is formed on the colored film by a vacuum deposition method, The degassing may elongate the vacuum evacuation time and may adversely affect the resistance value and etching property of the transparent conductive film. If the addition amount of the ionic polymer is small, the effect of reducing the resistance value becomes insufficient.

Of the three colored films and protective film of the present invention,
The surface resistance of at least one film is 10 ⁹ Ω / □ to 10
It is important to be in the range of ¹² Ω / □. The surface resistance of at least one of the colored film and the protective film is 10 ⁹ Ω
In order to control in the range of / □ to 10 ¹² Ω / □, it is effective to add a surfactant or / and an ionic polymer to the colored film or the protective film. If the surface resistance of the colored film or the protective film is set to be less than 10 ⁹ Ω / □, a large amount of a surfactant or an ionic polymer for reducing the resistance value must be added, resulting in the characteristics of the colored film. May cause difficulty in coating or decrease the transparency of the colored film. In addition, the hygroscopicity is increased by increasing the addition amount of the surfactant or the ionic polymer, and the heat resistance, light resistance, chemical resistance, and weather resistance of the colored film are deteriorated, or the vacuum deposition method on the colored film is performed. When a transparent conductive film, a silicon oxide film, or a transparent conductive film is formed in, the degassing from the colored film may lengthen the vacuum evacuation time and may adversely affect the resistance value or etching property of the transparent conductive film. . The surface resistance of the colored film is 1
When it is larger than 0 ¹² Ω / □, the effect of reducing the charge amount is not sufficient, and defects often appear when the colored film is applied.
Which of the three colored films and the protective film has the surface resistance value controlled in the range of 10 ⁹ Ω / □ to 10 ¹² Ω / □ is
It is selected according to the characteristics such as the pigment dispersibility and viscosity of the colored film paste, the state of the underlying film, the coating method, etc., but it should be selected from the film with many defects and the underlying film with many defects. Is preferred. At least one of the three colored films and the protective film of the present invention has a surface resistance of 2 × 10 ⁹
It is more preferably in the range of Ω / □ to 5 × 10 ¹¹ Ω / □, and most preferably in the range of 5 × 10 ⁹ Ω / □ to 8 × 10 ¹⁰ Ω / □. In order to control the surface resistance, the ionic polymer and the surfactant are solid components of the paste for forming the target coating film, that is, the coating weight excluding the ionic polymer and the surfactant. , 0.001
% To 20% by weight, preferably 0.01 to 10% by weight.

As the ionic polymer, the above-mentioned ionic polymers can be adopted.

Examples of the surfactant of the present invention include anionic surfactants having a substituent such as carboxylic acid, sulfuric acid ester, sulfonic acid and phosphoric acid ester, and cationic surfactants having a substituent such as quaternary ammonium salt. Although amphoteric surfactants such as activators and alkyl betaines, and nonionic surfactants such as glycerin fatty acid esters can be adopted,
Anionic surfactants and cationic surfactants are preferable because they have a large effect on reducing the surface resistance. Specific examples of preferably used anionic surfactants include benzenesulfonic acid, dodecylsulfonic acid, octyl alcohol phosphoric acid ester, lauryl alcohol phosphoric acid ester, stearyl alcohol phosphoric acid ester, oleyl alcohol phosphoric acid ester, octyl alcohol. Mention may be made of ethylene oxide adduct phosphoric acid ester, lauryl alcohol ethylene oxide adduct phosphoric acid ester and salts thereof. Lauryl trimethyl ammonium methosulfate can be mentioned as a specific example of the cationic surfactant that is preferably used. Specific examples of the amphoteric surfactants that are preferably used include lauryl dimethyl betaine and alkyl imidazolinium betaine. Specific examples of nonionic surfactants that are preferably used include glyceric acid fatty ester, polyglyceric acid fatty ester, and N-hydroxy-N-2.
-Hydroxyalkylamine and N, N-bis- (2-hydroxyethyl) alkylamine can be mentioned.

Since the surface active agent has a low molecular weight, it is likely to be bleed out on the surface of the film, which may reduce the adhesive force or deteriorate the effect of reducing the resistance value with time. preferable. Ionic polymers are preferable because they have excellent heat resistance and chemical resistance as compared with surfactants. It is permissible to add a surfactant to the paste for the purpose other than reducing the resistance value, for example, for improving the dispersibility of the pigment. At least one of the three colored films and the protective film of the present invention has a surface resistance of 10 ⁹ Ω / □ to 10 ¹² Ω.
In order to control in the range of / □, it is appropriately permitted to add conductive particles while allowing deterioration of contrast and coating property.

As the transparent conductive film of the present invention, a tin oxide indium oxide (ITO) film formed by a vacuum deposition method such as a vacuum deposition method or a sputtering method is usually employed.
In addition, indium oxide, tin oxide, zinc oxide and the like can also be used. The amount of tin oxide added to the ITO film is 3% by weight
To 15% by weight. 1 nm to 100
It is preferable that a silicon oxide film having a thickness in the range of nm is inserted between the colored film and the transparent conductive film or between the protective film and the transparent conductive film. The silicon oxide film prevents the transparent conductive film from deteriorating the electrical properties and etching characteristics due to degassing from the colored film when the transparent conductive film is formed, and prevents the elution of ionic impurities from the colored film into the liquid crystal. There is.

The polyimide polymer of the present invention means a polymer having an imide ring or other cyclic structure from a polyimide precursor containing a structural unit represented by the general formula (1) as a main component, by heating or a suitable catalyst. (Polyimide, polyamide-imide).

[0022]

Embedded image Here, n in the general formula (1) is 1 to 2. 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 include phenyl group, biphenyl group, terphenyl group, naphthalene group, perylene group, diphenyl ether group, diphenylsulfone group, diphenylpropane group, benzophenone group, biphenyltrifluoropropane group, cyclobutyl group, cyclopentyl group, and the like. However, the present invention is not limited to these. R ₂ is a divalent organic group having at least 2 carbon atoms. R ₂ from the viewpoint of heat resistance
Is preferably a divalent group containing a cyclic hydrocarbon, an aromatic ring or an aromatic heterocycle and having 6 to 30 carbon atoms. R ₂
Examples of phenyl group, biphenyl group, terphenyl group, naphthalene group, perylene group, diphenyl ether group, diphenyl sulfone group, diphenyl propane group,
Examples thereof include a benzophenone group, a biphenyltrifluoropropane group, a diphenylmethane group and a cyclohexylmethane group, but are not limited thereto. The polymer whose main component is the structural unit represented by the general formula (1) is
Each of R ₁ and R ₂ may be composed of one of these, or may be a copolymer composed of two or more of each. In order to improve the adhesive strength with the substrate, bis (3-aminopropyl) tetramethyldisiloxane having a siloxane structure may be copolymerized as a diamine component within a range that does not lower the heat resistance. In addition, an anhydride such as maleic anhydride may be added as a blocking agent for the amine terminal, depending on the terminal concentration, after the completion of the polymerization of the polyimide precursor, and reacted. The higher the molecular weight, the better the mechanical properties of the polyimide film. Therefore, it is desired that the molecular weight of the polyimide precursor is also large. On the other hand, when patterning a polyimide precursor film by wet etching, if the molecular weight of the polyimide precursor is too large, there is a problem that the time required for development becomes too long. For this reason, the degree of polymerization is usually preferably in the range of 5 to 1000.

The paste for colored film of the present invention contains a resin, a coloring material, an ionic polymer and a solvent, and the resin contains the structural unit represented by the general formula (1) as a main component. A polyimide precursor is used, and the pigment is used as the coloring material.

In the colored film paste of the present invention, the polyimide precursor and the pigment are usually used in a weight ratio of 2: 8 to 9 :.
1, preferably 3: 7 to 8: 2, more preferably 4: 6.
The mixture is used in the range of 7: 3. If the amount of the polyimide precursor is too small, the adhesion between the colored film and the substrate will be poor, and if the amount of the pigment is too small, the degree of coloring will be insufficient.

The solvent for the colored film paste of the present invention is an amide-based polar solvent such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N-dimethylformamide, β-propiolactone, γ-butyrolactone. , Lactone solvents such as γ-valerolactone, δ-valerolactone, γ-caprolactone and ε-caprolactone, ethylene glycol such as methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol and propylene glycol monoethyl ether, propylene glycol Derivatives, propylene glycol monoethyl ether acetate, ethyl acetoacetate, methyl-3
One or more kinds of fatty acid esters such as -methoxypropionate and 3-methyl-3-methoxybutylacetate can be used, but not particularly limited.

It is preferable to add 0.5% to 100% by weight of water to the polyimide precursor to the colored film paste of the present invention, because it has the effect of enhancing the dispersion of the pigment and suppressing the charge of the paste. 100% by weight of water added
If it exceeds the range, the coating film may be repelled and the transparency may be deteriorated.

A colloidal substance of inorganic fine particles may be added to the colored film paste of the present invention in order to improve the hardness of the colored film. Specific examples of the colloidal substance of inorganic fine particles include silica sol, titania sol, zirconia sol, etc., but are not particularly limited thereto. When the colloidal substance of inorganic fine particles is added, the addition amount thereof is preferably 1% by weight to 50% by weight of the polyamic acid, and more preferably 2% by weight to 30% by weight. If the added amount is too large, the colored film becomes brittle, and if the added amount is too small, the effect of improving the hardness of the colored film is not exhibited.

An example of the method of manufacturing the colored film paste and the method of manufacturing the color filter substrate of the present invention will be described, but the invention is not limited thereto.

First, a pigment-dispersed polyimide precursor composition which is a paste for a colored film is prepared. As a method for producing this, there are a method of mixing a dispersion liquid in which a pigment is previously dispersed in a solvent and a polyimide precursor solution, and a method of dispersing a pigment in a polyimide precursor solution. In either method, the pigment is dispersed in the solvent, but the dispersing method is not particularly limited, and various methods such as a ball mill, a sand grinder, a three roll mill, and a high speed impact mill can be used. There are several methods for adding an ionic polymer, such as adding it to a dispersion liquid in which a pigment is previously dispersed in a solvent, or adding it to a polyimide precursor solution before dispersing the pigment. It is determined in consideration of the reaction with and the dispersibility of the pigment.

Next, an example of a method for producing a color filter substrate for a liquid crystal display, which is a typical application of the colored film paste of the present invention, will be described, but the present invention is not limited thereto.

As the substrate, glass such as soda glass, non-alkali glass barium borosilicate glass, aluminum borosilicate glass, and quartz glass, or a transparent plastic substrate is usually used. In the case of soda glass containing sodium, it is preferable that the surface thereof be coated with a barrier layer such as a silicon oxide film for preventing elution of sodium.

The method for applying the colored film paste of the present invention onto a substrate includes a printing method, a spin coating method, a dipping method, a slit die method, a bar coater method, a blade coater method, a roll coater method and a spray method. Various methods can be used.

When applying the colored film paste onto the substrate, a silane coupling agent, an aluminum chelating agent,
If the surface of the substrate is treated with an adhesion aid such as a titanium chelating agent, the adhesion between the colored coating and the substrate can be improved.

The colored film paste is applied onto the transparent substrate by the method described above, and then the polyimide precursor colored film is formed by air drying, heat drying, vacuum drying or the like. For heat drying, use an oven, hot plate, etc.
It is preferable to carry out the treatment in the range of 0 ° C to 180 ° C for 1 minute to 3 hours. Next, a pattern is formed on the thus obtained polyimide precursor colored film by ordinary wet etching. First, a positive photoresist is applied on the polyimide precursor colored film to form a photoresist film. Subsequently, a mask is placed on the photoresist film, and ultraviolet rays are irradiated using an exposure device. After exposure, the photoresist film and the polyimide precursor colored film are simultaneously etched with a positive photoresist alkaline developer. After etching, the unnecessary photoresist film is removed.

The polyimide precursor colored film is then heated to be converted into a polyimide colored film. The heat treatment is usually carried out in air, in a nitrogen atmosphere, in vacuum, or the like for 5 minutes to 5 hours while the temperature is raised stepwise or the temperature range is selected continuously. The temperature range of heat treatment is 150 ° C to 450 ° C, preferably 180 ° C.
C. to 350.degree.

The above steps are performed for the colored film paste of three colors of red, green and blue and, if necessary, for the black matrix paste. The thickness of the colored film and the black matrix is selected from the range of 0.2 μm to 5 μm.

Further, a protective film made of acrylic, polyimide, polyamide-imide, silicone, polyimide-modified silicone or the like is further formed thereon for the purpose of improving heat resistance, chemical resistance, hardness, leveling of steps, and ion blocking property. Can be provided. The thickness of the protective film is from 0.1 μm to 5
It is selected from the range of μm.

If a protective film is used, a silicon oxide film and an ITO film are formed on the protective film by a vacuum deposition method such as a vacuum deposition method or a sputtering method on the protective film. Layered in order. The thickness of the silicon oxide film is selected from the range of 1 nm to 100 nm. The thickness of the ITO film is selected from the range of 30 nm to 500 nm.

In the STN type liquid crystal display color filter substrate, when the ITO film is etched in a stripe shape corresponding to the pixel size, first, a positive type photoresist is applied on the ITO film to form a photoresist film. Form. Subsequently, a mask is placed on the photoresist film, and ultraviolet rays are irradiated using an exposure device. After the exposure, the photoresist film is developed with a positive photoresist alkaline developer. After etching the ITO film with hydrochloric acid-ferric chloride aqueous solution or the like, the unnecessary photoresist film is removed.

It is permissible to insert a film for the purpose of improving the adhesiveness, improving the optical characteristics, improving the electrical characteristics, etc. between the respective films of the color filter substrate. It is preferable to remove the charge from the glass substrate or the base film with ionized air or the like immediately before applying the colored film or the protective film, because the effect of the present invention is promoted.

The color filter substrate of the present invention can be applied not only to a liquid crystal display but also to an image sensor, an image pickup device and the like.

[0042]

EXAMPLES The present invention will now be specifically described based on examples, but the invention is not limited thereto. [Characteristics measurement / evaluation method] (1) Measurement of surface resistance A measurement sample is placed in an atmosphere of 20 ° C and 50% RH, and a surface resistance meter "ULTRA MEGAOHMMETER SM-8210" (manufactured by Toa Denpa Kogyo KK) is used. It was measured.

Example 1 300 equipped with a thermometer and a dry nitrogen inlet and a stirrer
In a 0 ml four-necked flask, 147 g of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 525 g of γ-butyrolactone, and 220 N-methyl-2-pyrrolidone were added.
Then, 95.1 g of 4,4′-diaminodiphenyl ether and 6.2 g of bis-3- (aminopropyl) tetramethyldisiloxane were added, and the mixture was charged with dry nitrogen.
The mixture was stirred at 60 ° C. for 3 hours to obtain a polyamic acid solution.

Pigment Green 7: 5.25 g, Pigment Yellow 83: 1.05 g, γ-butyrolactone 83.7 g, and 15 g of polystyrene sulfonic acid lithium salt having a molecular weight of 40,000 were added to a homogenizer together with 90 g of glass beads, and the mixture was added at 30 rpm at 7,000 rpm. After minute dispersion, the glass beads were removed by filtration to obtain a green pigment dispersion.

A solution prepared by diluting 25 g of the polyamic acid solution with 25 g of γ-butyrolactone was added to 47 g of the pigment dispersion and mixed to obtain a green colored film paste.

Pigment Red 177: 5.
A red colored film paste was obtained in the same manner as the green colored film paste, except that 25 g, Pigment Yellow 83: 0.75 g were used, and the addition amount of the lithium polystyrene sulfonate was 20 g.

A blue colored film paste was obtained in the same manner as the green colored film paste, except that Pigment Blue 15: 6 g was used as the pigment.

On the barium borosilicate glass, the paste for green coloring film was applied with a spinner so that the thickness of the polyimide after heating would be 1.6 μm, and the temperature was 20 ° C. at 20 ° C.
It was dried for a minute, and further heated in a nitrogen atmosphere at 290 ° C. for 40 minutes to be converted into a polyimide film. The surface resistance of the green colored film thus obtained was 7 × 10 ¹⁰ Ω / □. Similarly, a blue colored film was obtained from the blue colored film paste. The surface resistance of the blue colored film thus obtained was 5 × 10 ¹⁰ Ω / □. Similarly, a red colored film was obtained from the paste for red colored film. The surface resistance of the red colored film thus obtained is 5 × 1.
It was 0 ¹⁰ Ω / □.

On a barium borosilicate glass on which a black matrix had been formed by etching a chromium film in a lattice pattern having openings of 250 μm × 60 μm, a spinner was formed so that the film thickness after heating became polyimide was 1.6 μm. Then, the green colored film paste was applied and dried at 120 ° C. for 20 minutes. Similarly, when the paste for a green colored film was applied to the other 19 substrate glasses and dried, no repelling of the green colored film or uneven coating was observed. A positive photoresist (OFPR-800 manufactured by Tokyo Ohka Kogyo Co., Ltd.) was applied on this film and dried by heating at 80 ° C. for 20 minutes to obtain a photoresist film having a film thickness of 1 μm. Canon UV exposure machine PLA-
Using 501F, ultraviolet rays having an intensity of 50 mJ / cm ² at a wavelength of 365 nm were irradiated through a photomask made of chromium. After the exposure, the photoresist film and the colored film were simultaneously developed by immersing them in a developing solution composed of a 2.38 wt% aqueous solution of tetramethylammonium hydroxide. After etching, the unnecessary photoresist film was peeled off with methyl cellosolve acetate. Further, the green colored film thus obtained was heat-treated in a nitrogen atmosphere at 290 ° C. for 40 minutes to be converted into a polyimide film. The paste for blue coloring film is applied onto 20 substrates having the green coloring film formed thereon by a spinner so that the thickness of the polyimide after heating becomes 1.6 μm, and the temperature is 120 ° C. for 20 minutes. When dried, one of the 20 sheets had a diameter of 70 μm and a diameter of 10
The blue colored film was repelled and no coating unevenness was observed, except that one spot of 0 μm repellency was observed. The blue colored film was patterned in the same manner as the green colored film to convert it into a polyimide film. On the 20 substrates with the green and blue colored films formed thereon, the film thickness when converted to polyimide after heating is 1.6 μm.
Apply the red colored film paste with a spinner so that
When it was dried at 120 ° C. for 20 minutes, one of 20 sheets had one repellency with a diameter of 70 μm, and the red colored film had no repellency and no coating unevenness was observed. The red colored film was patterned in the same manner as the green colored film to convert it into a polyimide film.

Acrylic (“Optomer”) on this substrate
A protective film made of SS Japan Synthetic Rubber Co., Ltd. was applied with a spinner so that the film thickness after heating would be 2 μm, and the film was applied at 90 ° C. for 1
Heat treatment was performed for 5 minutes and subsequently at 280 ° C. for 1 hour.

A thickness of 10 n is formed on the protective film by sputtering.
m silicon oxide film is formed, followed by 150 nm thick IT
An O film was formed to complete the color filter substrate. Compared to Comparative Example 1, the occurrence of defects during coating of the colored film was less.

Example 2 A polyamic acid solution was obtained in the same manner as in Example 1. A green, blue, and red pigment dispersion was prepared in the same manner as in Example 1 except that 11 g of a polyglycerin fatty acid ester having a molecular weight of 10,000 was added instead of the polystyrene sulfonate lithium salt, and the same as in Example 1. Then, the polyamic acid solution and γ-butyrolactone were mixed to obtain green, blue, and red colored film pastes.

The paste for green coloring film was applied onto barium borosilicate glass with a spinner so that the thickness of the polyimide after heating would be 1.6 μm, and the temperature was 20 ° C. at 20 ° C.
It was dried for a minute, and further heated in a nitrogen atmosphere at 290 ° C. for 40 minutes to be converted into a polyimide film. The surface resistance of the green colored film thus obtained was 4 × 10 ¹¹ Ω / □. Similarly, a blue colored film was obtained from the blue colored film paste. The surface resistance of the blue colored film thus obtained was 2 × 10 ¹¹ Ω / □. Similarly, a red colored film was obtained from the paste for red colored film. The surface resistance of the red colored film thus obtained is 5
It was × 10 ¹¹ Ω / □.

On barium borosilicate glass on which a black matrix was formed by etching in the same lattice pattern as in Example 1, the film thickness when converted to polyimide after heating was 1.6 μm.
The paste for green colored film was applied by a spinner so as to have m, and dried at 120 ° C. for 20 minutes. Similarly, when the paste for a green colored film was applied to the other 19 substrate glasses and dried, no repelling of the green colored film or uneven coating was observed. The green colored film was patterned in the same manner as in Example 1,
It was converted into a polyimide film by heat treatment. The paste for blue coloring film is applied onto 20 substrates having the green coloring film formed thereon by a spinner so that the thickness of the polyimide after heating becomes 1.6 μm, and the temperature is 120 ° C. for 20 minutes. When dried, one of the 20 sheets had one repellency with a diameter of 80 μm, and one sheet had one repellency with a diameter of 60 μm.
The blue colored film was patterned in the same manner as the green colored film to convert it into a polyimide film. The paste for the red colored film was applied onto 20 substrates having the green and blue colored films formed thereon by a spinner so that the thickness of the polyimide after heating would be 1.6 μm, and at 120 ° C. When dried for 20 minutes, 2
One of 0 sheets has one repelling point with a diameter of 90 μm.
One repellency having a diameter of 70 μm was observed on the sheet. The red colored film was patterned in the same manner as the green colored film to convert it into a polyimide film.

A protective film was formed on this substrate in the same manner as in Example 1 except that 2% by weight of polyglycerin fatty acid ester having a molecular weight of 10,000 was added to acrylic ("Optomer" SS Japan Synthetic Rubber Co., Ltd.). When 20 sheets were formed, one repellency having a diameter of 70 μm was found on one of the 20 sheets, and one repellency having a diameter of 100 μm was found on one sheet. A silicon oxide film having a thickness of 10 nm is formed on the protective film by sputtering,
Subsequently, an ITO film having a thickness of 150 nm was formed to complete the color filter substrate. Compared to Comparative Example 1, the occurrence of defects during coating of the colored film and the protective film was less.

Comparative Example 1 A polyamic acid solution was obtained in the same manner as in Example 1. Green, blue and red pigment dispersions were prepared in the same manner as in Example 1 except that lithium polystyrene sulfonate was not added, and the polyamic acid solution and γ-butyrolactone were prepared in the same manner as in Example 1. By mixing, pastes for green, blue and red colored films were obtained.

On the barium borosilicate glass, the paste for green coloring film was applied with a spinner so that the film thickness when it became polyimide after heating would be 1.6 μm, and at 120 ° C. for 20 minutes.
It was dried for a minute, and further heated in a nitrogen atmosphere at 290 ° C. for 40 minutes to be converted into a polyimide film. The surface resistance of the green colored film thus obtained was 7 × 10 ¹⁷ Ω / □. Similarly, a blue colored film was obtained from the blue colored film paste. The surface resistance of the blue colored film thus obtained was 6 × 10 ¹⁷ Ω / □. Similarly, a red colored film was obtained from the paste for red colored film. The surface resistance of the red colored film thus obtained is 2
It was × 10 ¹⁷ Ω / □.

On barium borosilicate glass on which a black matrix was formed by etching in the same lattice pattern as in Example 1, the film thickness when converted to polyimide after heating was 1.6 μm.
The paste for green colored film was applied by a spinner so as to have m, and dried at 120 ° C. for 20 minutes. Similarly, when the green colored film paste was applied to the other 19 substrate glasses and dried, one of the 20 substrates had two repellants with a diameter of 50 μm. The green colored film was patterned in the same manner as in Example 1 and converted into a polyimide film by heat treatment. The paste for blue coloring film is applied onto 20 substrates having the green coloring film formed thereon by a spinner so that the thickness of the polyimide after heating becomes 1.6 μm, and the temperature is 120 ° C. for 20 minutes. When dried, one of the 20 sheets had one repelling point with a diameter of 200 μm and a diameter of 90 μm, and one sheet had a diameter of 130 μm.
There are two repellants of m and one repellant of 90 μm in diameter,
One repellency having a diameter of 80 μm was seen on one sheet. The blue colored film was patterned in the same manner as the green colored film to convert it into a polyimide film. Substrate 2 on which the green and blue colored films are formed
The red coloring film paste was applied onto 0 sheet by a spinner so that the film thickness when heated to become polyimide was 1.6 μm, and dried at 120 ° C. for 20 minutes. One repellency with a diameter of 160 μm was seen on one sheet, one repellency with a diameter of 310 μm, 120 μm and 70 μm was seen on one sheet, and two repellency with a diameter of 60 μm was seen on one sheet. The red colored film was patterned in the same manner as the green colored film to convert it into a polyimide film.

A protective film was formed on this substrate in the same manner as in Example 1. As a result, one of the 20 sheets had two repelling points of 200 μm and one repelling point of 70 μm in diameter, and two sheets had a repelling rate of 50 μm. One repelling is seen, and two pieces have a diameter of 110
One repellency of μm was seen. Protective film A silicon oxide film having a thickness of 10 nm was formed on the protective film by sputtering, and then an ITO film having a thickness of 150 nm was formed to complete a color filter substrate.

[0060]

According to the present invention, the surface resistance of the colored film or the protective film can be reduced without adding particles of metal oxide or the like, so that the contrast is lowered due to the scattering of light. , Without deteriorating the coating characteristics
It is possible to provide a colored film or a protective film with less repellency and uneven coating. Further, the surfactant and / or the ionic polymer used in the present invention tends to segregate on the surface of the film when the colored film or the protective film is dried and heated, and is excellent in static elimination efficiency.

Claims (7)

[Claims] 1. A three-color colored film made of a resin and a coloring material on a substrate, a transparent conductive film, or a three-color colored film made of a resin and a coloring material on a substrate, a protective film made of a resin, and a transparent film. A color filter substrate having conductive films laminated in this order, wherein at least one of the three colored films and the protective film contains an ionic polymer. . 2. A three-color colored film made of a resin and a coloring material on a substrate, a transparent conductive film, or a three-color colored film made of a resin and a coloring material on a substrate, a protective film made of a resin, and a transparent film. A color filter substrate having conductive films stacked in this order, wherein at least one of the three colored films and the protective film has a surface resistance in the range of 10 ⁹ Ω / □ to 10 ¹² Ω / □. A color filter substrate characterized by being present. 3. The ionic polymer is contained in a film having a surface resistance in the range of 10 ⁹ Ω / □ to 10 ¹² Ω / □ among the three colored films and the protective film. The color filter substrate according to claim 2. 4. The color filter substrate according to claim 1, wherein the resin forming the three colored films is a polyimide-based polymer, and the coloring material is a pigment. 5. The color filter substrate according to claim 1, wherein the resin forming the protective film is a polyimide-based polymer. 6. A colored film paste comprising a resin, a coloring material and an ionic polymer. 7. The colored film paste according to claim 6, wherein the resin is a polyimide polymer and the coloring material is a pigment.