JPH11271526A - Transparent protective coat for color filter, color filter and liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of defects in liq. crystal display such as interference fringes by using a transparent protective coat for a color filter having a refractive indax in a specified range. SOLUTION: The transparent protective coat for a color filter has a refractive index in the range of 1.55-1.8. An epoxy resin or a polyimide-contg. resin is preferably used as the matrix resin of the protective coat. Superfine oxide particles and/or a metal alkoxide are contained in the resin so as to increase the refractive index. The oxide of the superfine oxide particles is preferably TiO2 , Sb2 O5 , ZrO2 or Al2 O3 . The metal alkoxide is preferably a titanium alkoxide such as Ti(OCH(CH3 )2 )4 or a zirconium alkoxide such as Zr(OCH2 CH2 CH2 CH3 )4 or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent protective film for a color filter, a color filter, and a liquid crystal display device, which suppresses display defects such as interference fringes caused by uneven cell gaps. The present invention relates to a transparent protective film for use, a color filter, and a liquid crystal display device using the color filter.

[0002]

2. Description of the Related Art In recent years, many color liquid crystal display devices in which a color filter is combined with a liquid crystal display element have been proposed. Typical driving methods for a color liquid crystal display device include simple matrix driving using a super-twisted nematic method or the like and active matrix driving using a thin film transistor (TFT) method. The manufacturing process of a color liquid crystal display device is a process of manufacturing two glass substrates, that is, a substrate having electrodes or TFTs, and a color filter substrate, bonding the two substrates together, and injecting liquid crystal into a gap therebetween. And a module step of attaching a drive circuit to the cell. Here, the color filter is composed of a large number of picture elements each including three primary color pixels of red, green, and blue formed on a light-transmitting substrate. In order to enhance the contrast, a light shielding region (black matrix) having a certain width is provided.

[0003] In the manufacturing process of a color liquid crystal display device, a process of forming a cell is as follows. First, an alignment film is formed on two glass substrates and rubbing is performed. Subsequently, a sealing material containing a rod spacer is applied to one of the substrates,
At this time, spacers called micropearls are sprayed on the substrates in order to control a gap between the two substrates. A liquid crystal is injected into a gap between the two bonded substrates, the injection port is sealed with an ultraviolet curable resin or the like, and then a polarizing plate is attached to the outside of the two glass substrates to complete a cell.

When a liquid crystal display device is formed through the cell forming process as described above, non-uniformity occurs in the cell gap due to sinking of the rod spacer and poor support of the bead spacer in the pixel portion and the black matrix portion. as a result,
Display defects such as interference fringes may occur in the liquid crystal display device.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a suitable transparent protective film for a color filter, a color filter, and a liquid crystal display using the color filter in order to prevent the occurrence of such a defective liquid crystal display as interference fringes. No device is provided.

[0006]

In order to achieve the object of the present invention, the present invention has the following arrangement.

[0007] The transparent protective film for a color filter of the present invention is characterized in that the refractive index is in the range of 1.55 to 1.8.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A transparent protective film for a color filter is provided for the purpose of protecting the black matrix and the colored layer, improving the smoothness of the surface of the color filter, and preventing the color filter from contaminating the liquid crystal. In particular, when a resin black matrix is used as the black matrix, in order to reduce the color filter surface step based on the thickness of the resin black matrix,
A transparent protective film for a color filter may be required.

The transparent protective film for a color filter has an adhesive property with a lower layer and an upper layer, a property of blocking impurities, a smoothness, a light resistance,
A wide range of properties such as moisture and heat resistance, solvent resistance, chemical resistance, toughness, transparency and heat resistance are required.

The authors report that the display failure such as the interference fringes described above is caused by a transparent protective film for a color filter and a colored layer composed of three primary colors, or a backlight at the interface between the transparent protective film for a color filter and the transparent electrode layer. Was found to be caused by the reflected light. That is, it has been found that, when the reflected light of the backlight at the interface is large, the reflected light interferes with the direct light of the backlight, whereby interference fringes appear. Therefore, in order to suppress the occurrence of interference fringes, the reflected light itself must be reduced, or
Two methods of making reflected lights interfere with each other and cancel each other are effective.

First, the former method will be described. At present, the refractive indices of the colored layer composed of three primary colors and the transparent conductive film are 1.7 to 2.0 and 1.7 to 1.8, respectively.
Since the refractive index is higher than the refractive index of the transparent protective film for a color filter, reflection of the backlight occurs at each interface. Therefore, in order to solve the problem, the coloring layer and the transparent conductive film are formed by lowering the refractive index of the coloring layer and the transparent conductive film and / or increasing the refractive index of the transparent protective film for a color filter. It is necessary to reduce the difference in refractive index between the color filter and the transparent protective film for a color filter.

In the case of the colored layer, since the absorption by the dye is large, the refractive index is represented by an apparent refractive index (complex refractive index) including the contribution by the absorption. In order to evaluate the difference, it is preferable to use the actual refractive index from which the contribution due to absorption is removed in consideration of the extinction coefficient.

Here, when polyimide is used as the resin for the colored layer, the actual refractive index of the colored layer is 1.7 to 1.8.
And it becomes difficult to lower the actual refractive index of the colored layer.

[0014] On the other hand, indium / tin oxide (ITO) is usually used for the transparent conductive film. Low resistance is required for the transparent conductive film, and for that purpose, it is necessary to increase the crystallinity of ITO. When the degree of crystallinity is increased, the refractive index is increased. Therefore, it is difficult to reduce the refractive index of ITO, that is, the transparent conductive film.

Therefore, the colored layer and the transparent conductive film
In order to reduce the refractive index difference between the transparent protective film for a color filter and the transparent protective film for a color filter, it is preferable to increase the refractive index of the transparent protective film for a color filter.

On the other hand, in the latter method, by controlling the thicknesses of the colored layer, the transparent protective film for a color filter, and the transparent conductive film, the phases of the reflected light generated at the respective interfaces are adjusted to cause interference therebetween. Thus, the reflected light can be reduced.

Hereinafter, a method for increasing the refractive index of the transparent protective film for a color filter will be described in detail.

In the transparent protective film for a color filter of the present invention, it is necessary to increase the film density and / or the electronic polarizability of the entire film in order to increase the refractive index. In order to increase the film density, it is effective to reduce the aperture ratio of the film by controlling the temperature of the heat treatment, or to promote the densification of the film by reducing the fractal dimension of the resin. On the other hand, in order to increase the electron polarizability of the entire film, it is necessary to adopt a structure that contains many groups such as aromatics and has a long conjugated system. Is effective.
Further, the transparent protective film for a color filter is not limited to a uniform type, but may be a resin having an electronic polarizability larger than that of a resin, in other words, a resin containing an inorganic oxide having a large refractive index. This is a very effective means.

Therefore, in the transparent protective film for a color filter of the present invention, it is preferable to use aromatic polyimide, an acrylic resin containing sulfur or bromine, an epoxy resin containing a large amount of aromatics, or the like as a resin.

Further, in the transparent protective film for a color filter of the present invention, in order to increase the refractive index, the resin contains one or both of the following (a) and (b) or both. A membrane can be used.

(B) is a form present in the thermosetting resin solution composition for a color filter, and the transparent protective film for a color filter is in a form containing a metal oxide chemically.

(A) TiO ₂ , Sb ₂ O ₅ , ZrO ₂ , A
l ₂ O ₃ , Nb ₂ O ₅ , MnO ₂ , PbO, Bi
Ultrafine oxide particles such as ₂ O ₃ , SnO ₂ , HfO ₂ and Nd ₂ O ₃ .

(B) Ti (OCH (CH ₃ ) ₂ ) ₄ , Hf
(OCH ₂ CH ₂ CH ₂ CH ₃ ) ₄ , Ta (OC ₂ H ₅ ) ₅ , Z
r (OCH ₂ CH ₂ CH ₂ CH ₃ ) ₄ , Ba (OC ₂ H ₅ ) ₂ ,
Pb (OCH ₂ CH ₂ CH ₂ CH ₃ ) ₂ , Al (OC
_{2 H 5) 3, Zn (} OC 2 H 5) 2, Ga (OCH 3) 3, Ge
(OC ₂ H ₅ ) ₄ , W (OC ₂ H ₅ ) ₆ , Nb (OC
_{2 H 5) 5, Mo (} OC 2 H 5) 6, Y (OCH 3) 3, La
Metal alkoxides such as (OC ₂ H ₅ ) ₃ and Te (OC ₂ H ₅ ) ₄ .

Here, in order to improve the refractive index of the transparent protective film for a color filter, the oxide ultra-fine particles as shown in (a) are mentioned as an example. However, the present invention is not particularly limited thereto. Any ultrafine oxide particles having a higher refractive index than the resin component of the transparent protective film can be used. Here, the oxide ultrafine particles are oxide particles having a particle size smaller than the wavelength of visible light, and do not impair the transparency of the transparent protective film for a color filter. It is preferably 100 nm, more preferably 5 to 50 nm, and 5 to 10 nm.
Is more preferable. As materials, storage stability,
Considering versatility, cost, coloring, and refractive index improvement efficiency,
TiO ₂ , Sb ₂ O ₅ , ZrO ₂ , Al ₂ O _{3 and the} like are preferable. Furthermore, considering transparency, TiO ₂ , Sb ₂ O ₅
Is more preferred.

The ultrafine oxide particles can be added to the resin solution as it is. However, in order to finely disperse the ultrafine oxide particles and stabilize the dispersion, the ultrafine oxide particles are dispersed in a solvent. It is preferable to use an oxide ultrafine particle sol.

As the dispersion solvent for the oxide ultrafine particles, water,
Alcohols such as ethanol, methanol, isobutanol, 3-methyl-3-methoxybutanol, ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diethyl ether, isopropyl ether, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether , Ethers such as diethylene glycol diethyl ether, ethyl acetate, n-butyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol mono Me Ether acetates, amides and esters, N, N-dimethylformamide, N, N- dimethylacetamide and propylene glycol monoethyl ether acetate, .gamma.-butyrolactone,
Examples include pyrrolidones such as 2-pyrrolidone and N-methylpyrrolidone. Among these solvents, ester-based high-boiling solvents are preferred from the viewpoints of fine dispersibility of oxide ultrafine particles and storage stability, and they can be used alone or in combination of two or more. In particular, solvents such as propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether, and diethylene glycol monomethyl ether acetate are preferred from the viewpoint of high boiling point and storage stability. Also, in view of the storage stability of the oxide fine particle-containing color filter transparent protective film coating solution, the dispersion solvent of the oxide fine particles is preferably the same as the solvent used in the color filter transparent protective film. .

The addition of the metal alkoxide (b) is also an effective means for improving the refractive index. It is known that metal alkoxides other than silicon-based alkoxides generate a hydrolyzate in the presence of water or an alcohol and an acidic catalyst, and are polymerized by a condensation reaction. Therefore, in a system in which water or an acidic catalyst is present, the storage stability of the coating liquid may be deteriorated. However, the metal complex formed by the reaction of the β-diketone or β-keto acid ester with the metal alkoxide can suppress the hydrolysis and the condensation reaction, so that the storage stability can be improved. Therefore, when adding a metal alkoxide, depending on the resin or solvent used, a method of directly adding a metal alkoxide,
Alternatively, it is necessary to select one of the methods of adding a metal alkoxide after converting it into a metal complex.

Among the metal alkoxides of (b), from the viewpoint of economy, versatility and transparency, Ti (OCH (C
_{H 3) 2) 4, Hf} (OCH 2 CH 2 CH 2 CH 3) 4, Ta
(OC ₂ H _{5) 5,} it is preferable to use _{Zr (OCH 2 CH 2 CH 2} CH 3) 4. Among them, especially Ti (OC
Titanium such as H (CH ₃ ) ₂ ) ₄ and Zr (OCH ₂ CH ₂ CH ₂ CH ₃ ) ₄ or alkoxide of zirconium is more preferable from the viewpoints of stability of metal complex formation and simplicity. Specific examples of β-diketones and β-keto acid esters include acetylacetone, benzoylacetone, dibenzoylmethane, methyl acetoacetate, ethyl acetoacetate, benzoylacetoacetate, ethyl benzoyl acetate, methyl benzoyl acetate, and the like. Specific examples of titanium and zirconium alkoxides used in the present invention include tetramethoxytitanium, tetraethoxytitanium, tetraisopropoxytitanium, tetra (n-propoxy) titanium, tetra (n-butoxy) titanium, and tetraisobutoxytitanium. ,
Tetra (s-butoxy) titanium, tetra (t-butoxy) titanium, tetra (n-pentoxy) titanium, tetra (t-pentoxy) titanium, tetra (n-hexoxy)
Titanium, tetra (n-heptoxy) titanium, tetra (n
-Octoxy) titanium, tetraphenoxytitanium, tetrastearoxytitanium, tetramethoxyzirconium,
Tetraethoxyzirconium, tetraisopropoxyzirconium, tetra (n-propoxy) zirconium,
Tetra (n-butoxy) zirconium, tetraisobutoxyzirconium, tetra (s-butoxy) zirconium, tetra (t-butoxy) zirconium, tetra (n
Titanium or zirconium such as -pentoxy) zirconium, tetra (t-pentoxy) zirconium, tetra (n-hexoxy) zirconium, tetra (n-heptoxy) zirconium, tetra (n-octoxy) zirconium, tetraphenoxyzirconium, tetrastearoxyzirconium Alkoxides. Specific examples of metal complexes prepared using these include titanium acetylacetonate, titanium benzoylacetonate, titanium benzoylacetoacetate, titanium acetoacetate, zirconium acetylacetonate, zirconium benzoylacetonate, zirconium benzylacetoacetate, and zirconium acetoacetate. Among them, titanium acetylacetonate and zirconium acetylacetonate are particularly preferable from the viewpoint of storage stability and cost. When no problem such as storage stability occurs, only the metal alkoxide may be directly added.

In the present invention, the metal complex can be formed by synthesis from a metal, synthesis from a metal halide, synthesis from a metal salt other than a metal halide, synthesis from a metal oxide or hydroxide, organic metal The synthesis from a compound may be mentioned, but from the viewpoint of availability and toxicity, synthesis from a metal alkoxide is preferred.

Since the above-described method of incorporating a metal alkoxide into a resin is carried out through a solution state, it is possible to uniformly react with the resin at a molecular level.

As a matrix resin of the transparent protective film for a color filter, an epoxy resin, an acrylic epoxy resin, a siloxane resin, a silicone polyimide resin, a polyimide resin, or the like can be used, but is not limited thereto. Among these, it is preferable to use a resin containing an epoxy resin or a polyimide because the matrix resin itself has a high refractive index.

Examples of the epoxy resin include phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, cycloaliphatic epoxy resin, glycidylamine type epoxy resin, brominated epoxy resin, Those obtained by curing an aliphatic polyglycidyl ether or the like with a curing agent can be used.

The polyimide is preferably synthesized via a polyamic acid.

The polyamic acid can be obtained by reacting a tetracarboxylic dianhydride with a diamine.

In the synthesis of the polyamic acid, for example, aliphatic or alicyclic tetracarboxylic dianhydrides can be used. Specific examples thereof include:
1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,3,5-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-bicyclohexenetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,3,3a, 4,4
5,9b-Hexahydro-5- (tetrahydro-2,5
-Dioxo-3-furanyl) -naphtho [1,2-C] furan-1,3-dione; When an aromatic type is used, a polyamic acid which can be converted into a film having a high refractive index and good heat resistance can be obtained, and specific examples thereof are 3, 3 ′, 4, 4 ′. -Benzophenonetetracarboxylic dianhydride, pyromellitic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 3,3 ', 4,4'-diphenylsulfonetetracarboxylic dianhydride 4,4′-oxydiphthalic anhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 3,3 ′, 4,4′-paraterphenyltetracarboxylic dianhydride and 3,3 ′, 4,4′-methterphenyltetracarboxylic dianhydride are exemplified.

As the diamine, for example, an aliphatic or alicyclic diamine can be used. Specific examples thereof include 1,3-diaminocyclohexane,
4-diaminocyclohexane, 4,4'-diamino-
3,3′-dimethyldicyclohexylmethane, 4,4 ′
-Diamino-3,3'-dimethyldicyclohexyl and the like. In addition, when an aromatic type is used, a polyamic acid which can be converted into a film having a high refractive index and good heat resistance can be obtained.
4'-diaminodiphenylether, 3,4'-diaminodiphenylether, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 4,
4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfide, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2 , 6-Diaminotoluene, benzidine, 3,3'-dimethylbenzidine, 3,3'-dimethoxybenzidine, o-tolidine, 4,4'-diaminoterphenyl, 1,5-diaminonaphthalene, 3,3'-
Dimethyl-4,4'-diaminodiphenylmethane, 4,
4'-bis (4-aminophenoxy) biphenyl, 2,
2-bis [4- (4-aminophenoxy) phenyl] propane, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone and the like. When siloxane diamine is used as a part of the diamine, the adhesion to the inorganic substrate can be improved. The siloxane diamine is usually used in an amount of 1 to 20 mol% of the total diamine. If the amount of siloxane diamine is too small, the effect of improving the adhesiveness will not be exhibited, and if it is too large, the heat resistance will decrease.
Specific examples of the siloxane diamine include bis-3- (aminopropyl) tetramethylsiloxane. The present invention is not limited to this, and one or more diamines are used.

The synthesis of a polyamic acid is generally carried out by mixing and reacting a tetracarboxylic dianhydride and a diamine in a polar organic solvent. At this time, the degree of polymerization of the resulting polyamic acid can be adjusted by the mixing ratio of the diamine and the tetracarboxylic dianhydride.

In addition, there are various methods for obtaining a polyamic acid, for example, by reacting tetracarboxylic acid dichloride with a diamine in a polar organic solvent, and then removing hydrochloric acid and the solvent to obtain a polyamic acid.

Solvents used for coating the transparent protective film for color filters include water, alcohols such as ethanol, methanol, isobutanol and 3-methyl-3-methoxybutanol; methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone. Ketones, diethyl ether, isopropyl ether, tetrahydrofuran, dioxane, ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol diethyl ether, ethyl acetate, n-butyl acetate, 3-methoxy-3-methylbutyl acetate, ethylene glycol Monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene Recall monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, esters such as γ- butyrolactone, N, N
Amides such as -dimethylformamide and N, N-dimethylacetamide; and pyrrolidones such as 2-pyrrolidone and N-methylpyrrolidone. Among them, ester-based high-boiling solvents are preferred from the viewpoint of the smoothness of the transparent protective film for color filters, and they can be used alone or as a mixture of two or more. In particular, solvents such as propylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether, and diethylene glycol monomethyl ether acetate are preferred from the viewpoint of high boiling point and storage stability.

In the transparent protective film for a color filter of the present invention, the content of (a) is 2 to 300 parts by weight, preferably 3 to 200 parts by weight, more preferably 4 to 200 parts by weight, based on 100 parts by weight of the resin. 100 parts by weight. Component (a)
If the addition amount is less than this, the refractive index is not sufficiently improved, and if it is more than this, transparency, which is an important required characteristic of the transparent protective film for a color filter, is reduced, and cracks and the like are generated, resulting in film cracking. There is a possibility that the strength may be reduced.
On the other hand, the content of (b) is 2 to 200 parts by weight, preferably 3 to 100 parts by weight, based on 100 parts by weight of the resin.
It is more preferably 4 to 50 parts by weight. If the addition amount of the component (b) is less than this, the refractive index is not sufficiently improved, and if it is more than this, the smoothness and transparency which are the most important required properties of the transparent protective film for a color filter are impaired. .

The difference between the methods (a) and (b) is that (a) disperses ultrafine particles having a high refractive index physically in a transparent protective film for a color filter, whereas (b) chemically disperses them. This is a method of dispersing an inorganic oxide. In either of the methods (a) and (b), there is no significant difference in the effects on the refractive index, the smoothness, and the hardness of the film.

Coating properties of a transparent protective film for a color filter,
For the purpose of improving the surface smoothness, a surfactant can be added to the transparent protective film for a color filter of the present invention. The amount of surfactant added is usually 10
0.01 to 10 parts by weight, preferably 0.03 to 1 part by weight, based on 0 parts by weight. If the addition amount is too small, there is no effect of improving the coating properties, the smoothness of the film surface, or the dispersibility of the sol fine particles.If the addition amount is too large, on the contrary, the coating properties become poor or the toughness of the coating film decreases. The sol particles are reduced or aggregated.

Specific examples of the surfactant include silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, alkyl, fluorine-modified silicone oil, polyether, alcohol-modified silicone oil, amino-modified silicone oil, and epoxy-modified silicone oil. Modified silicone oils such as phenol, carboxy, mercapto-modified silicone oils, anionic surfactants such as ammonium lauryl sulfate, polyoxyethylene alkyl ether triethanolamine sulfate, cationic surfactants such as lauryl trimethyl ammonium chloride, lauryl dimethyl Amphoteric surfactants such as amine oxide, lauryl carboxymethyl hydroxyethyl imidazolium betaine, polyoxyethylene lauri Ether, polyoxyethylene stearyl ether, and the like nonionic surface active agents such as sorbitan monostearate. In the present invention, the surfactant is not limited thereto, and one of the above surfactants may be used alone, or two or more of them may be used in combination. The addition of the surfactant can be performed at any time before and after the addition of the oxide ultrafine particles or the metal alkoxide. However, care must be taken because the dispersibility of the oxide ultrafine particles may change at the time of addition.

Further, by introducing the inorganic oxides of (a) and (b), the difference in the coefficient of thermal expansion between the transparent protective film for a color filter and the glass substrate or transparent electrode is reduced. The adhesive strength between the film, the glass substrate, and the transparent electrode is improved. Therefore, there is no need to provide an inorganic intermediate film such as a SiO ₂ film between the transparent protective film for a color filter and the transparent electrode, and the production time and cost of the color filter may be reduced.

Next, the structure of the color filter of the present invention will be described.

The color filter of the present invention is characterized by comprising at least a black matrix, a coloring layer composed of three primary colors, and a transparent protective film for a color filter of the present invention, and is usually formed on a glass substrate. You. The thickness of the glass substrate is generally 0.5 mm to 1.5 m
m is often used.

Further, the color filter of the present invention comprises a plurality of dot-like spacers formed by laminating at least a black matrix, a coloring layer of three primary colors, and a coloring layer of three primary colors on a part of the black matrix. And the transparent protective film for a color filter of the present invention.

Here, the dot-shaped spacer makes it unnecessary to disperse the spacer in the liquid crystal display device manufacturing process, and greatly contributes to the improvement of the yield.

Further, these color filters include:
If necessary, a transparent electrode and an orientation film may be provided.

Next, each component of the color filter of the present invention will be described.

The black matrix is a light-shielding region between pixels and plays a role of improving the contrast of a liquid crystal display device. The black matrix is often formed of a metal thin film having a fine pattern. As the metal, Cr, Ni,
Al or the like is used. As a method of forming a metal thin film,
Sputtering, vacuum evaporation, and the like are widely used. A fine pattern can be obtained by forming a photoresist pattern on a metal thin film by a photolithography method and then etching the metal thin film using the resist pattern as an etching mask.

However, the black matrix formed of the metal thin film has a high manufacturing cost and causes a rise in the price of the color filter itself. Furthermore, Cr, which is generally used as a metal thin film for a black matrix, has a high reflectivity, and therefore has a problem that display quality is significantly reduced in places where external light is strong due to reflected light of Cr. Further, in order to reduce the reflectance of the black matrix, a method of providing a chromium oxide layer between Cr and the light-transmitting substrate has been proposed, but it is not preferable in terms of manufacturing cost.

Therefore, as a black matrix,
It is preferable to use a resin black matrix in which a light shielding agent is dispersed in a resin.

The light-shielding agent used for the resin black matrix includes carbon black, metal oxide powder such as titanium oxide and iron tetroxide, metal sulfide powder, metal powder, and red, blue, and green powders. And the like. Among them, carbon black is particularly preferable because of its excellent light-shielding properties.

When carbon black is used as the light-shielding agent, it is preferable to mix a pigment of a complementary color to carbon black in order to make the color tone achromatic. As pigments for complementary colors, blue pigments and purple pigments can be used alone or as a mixture of both.

When carbon black and a pigment of a color complementary to carbon black are used as the light-shielding agent, the ratio of carbon black contained in the light-shielding agent should be 50% by weight or more in order to obtain high light-shielding properties. It is preferably 60% by weight or more, and more preferably 70% by weight or more.

Examples of typical pigments used as complementary colors of carbon black are shown by color index numbers.
Examples of blue pigments include Pigment Blue 15, 15:
1, 15: 2, 15: 3, 15: 4, 15: 6, 16,
21, 22, 60, 64, etc., with Pigment Blue 15, 15: 1, 15: 2, 15: 6 being particularly preferred. Examples of purple pigments include Pigment Violet 19, 23, 29, 31, 32, 33, 36, 3
7, 39, 43, 50, etc., and particularly, Pigment Violet 23, 31, 33, 43, 50 is preferable.

In addition, green pigments, yellow pigments, orange pigments and the like may be added as appropriate, but the proportion incorporated into the light-shielding agent is preferably 10% by weight or less. If it is more than this, the light-shielding property per film thickness of the black matrix decreases, which is not preferable.

As the resin used for the resin black matrix, a transparent resin such as an acrylic resin or an epoxy resin can be used. However, from the viewpoint of heat resistance, light resistance and solvent resistance of the coating film, the resin is as follows. It is preferred to use polyimide. As the polyimide, those synthesized via the above-mentioned polyamic acid can be used. As the three primary color layers, a layer in which a dye is dispersed in a resin can be used. Pigments can be used in appropriate combination to represent the three primary colors. Dyes that can be used include, but are not limited to, pigments and dyes such as red, orange, yellow, green, blue, and purple. As the resin, a transparent resin such as an acrylic resin or an epoxy resin can be used. However, polyimide is preferably used as the resin in view of the heat resistance, light resistance, and solvent resistance of the coating film.

The transparent electrode is usually made of indium tin oxide (ITO). The transparent electrode is necessary to drive the liquid crystal.However, in the liquid crystal display device of the display method of the lateral electric field drive, the transparent electrode is not necessary on the color filter side, so the color filter without the transparent electrode is used. Is done.

Further, an alignment film is formed on the color filter of the present invention, if necessary. This may be obtained by rubbing an organic resin film such as polyimide, polyamide, or polyvinyl alcohol.

In the color filter of the present invention, by using the transparent protective film for a color filter of the present invention, the difference in refractive index between the colored layer and the transparent protective film for a color filter is in the range of 0.005 to 0.15. In addition, the difference in refractive index between the transparent conductive film and the transparent protective film for a color filter is set to 0.
It is preferred to be in the range of 005 to 0.15. From the viewpoint of balancing the required characteristics required for the transparent protective film for a color filter, in particular, from the viewpoint of maintaining good smoothness, the colored layer and the transparent protective film for the color filter, and the transparent conductive film and the transparent protective film for the color filter. Refractive index difference, 0.0
It is not preferable to make it smaller than 05. Further, from the viewpoint of reducing the reflected light at the interface, the difference in the refractive index is 0.1.
It is preferably 15 or less.

Further, in the color filter of the present invention, the reflectance of the pixel portion on the film surface side of the color filter is 10%.
% Or less. The reflectance is effective as an index for evaluating the degree of occurrence of display defects when a liquid crystal display device is manufactured. If the reflectance is 10% or less,
It is possible to suppress the occurrence of display defects such as interference fringes.

The reflectance was measured by using a spectrophotometer such as MCPD-2000 manufactured by Otsuka Electronics Co., Ltd. with reference to BK-7 (optical glass having a known refractive index) from the film surface side of the color filter. As in the air.

Here, the configuration of the color filter is not particularly limited, but at least a black matrix, a colored layer composed of three primary colors, or at least a black matrix, a colored layer composed of three primary colors,
Further, it is necessary that the black matrix be composed of a plurality of dot-shaped spacers formed by laminating colored layers of three primary colors on a part of the black matrix. Further, these color filters may be provided with a transparent protective film for a color filter, a transparent electrode, and an alignment film, if necessary.

When a transparent protective film for a color filter is provided, the transparent protective film for a color filter according to the present invention, that is, having a refractive index of 1.55 to 1.8, is used to reduce the reflectance to 10% or less. It is preferable to use a transparent protective film for a color filter within the range.

Even when a transparent protective film for a color filter having a low refractive index is used, the reflectance is adjusted by adjusting the thickness of the transparent protective film for a color filter, that is, by adjusting the phase of reflected light. It is possible to make it 10% or less.

A liquid crystal display of the present invention is characterized by using the color filter of the present invention. By using the color filter of the present invention, it is possible to suppress occurrence of display defects such as interference fringes. Since the color filter of the present invention is used for a color liquid crystal display device, it is preferable to use a thin film transistor (TFT) for driving the liquid crystal display device of the present invention.

[0069]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples.

Example 1 5 g of Epicoat 827 (bisphenol A type epoxy compound) manufactured by Yuka Shell Epoxy Co., Ltd., 5 g of γ-glycidoxypropylmethyldimethoxysilane, and Sb ₂ O ₅ methanol sol having a solid concentration of 30% 5 g of the solution
It was dissolved in -methoxy-3-methylbutyl acetate and adjusted to have a total solid concentration of 30%. After the obtained solution was filtered through a membrane filter having a pore size of 0.2 μm, the solution was applied on a glass substrate using a spin coater,
The coating was cured by heating in a thermostat at 150 ° C. for 10 minutes and in a thermostat at 230 ° C. for 30 minutes. The surface of the obtained coating film was extremely smooth, and no pinholes were observed. The film thickness measured by Tokyo Seimitsu Surfcom 1500A was 1 μm. When the refractive index of the coating film thus produced was measured, it was 400 nm.
At 1.67.

The measurement of the refractive index was obtained by ellipsometry. Polarization analysis is a method of irradiating polarized light on the film surface side of a glass substrate, reflecting the polarized light on the film surface, and measuring the change in the polarization state occurring at this time. Next, a color filter having the obtained color filter transparent protective film between the colored layer and the transparent electrode was prepared using an AEP-100 polarization analyzer manufactured by Shimadzu Corporation.

The color filter was prepared according to the following procedure.

(Preparation of Resin Black Matrix Layer) A 20 L reactor equipped with a thermometer, a dry nitrogen inlet, a heating / cooling device using hot / cold water, and a stirrer was charged with γ-
Butyrolactone 16644.1 g, 4,4′-diaminodiphenyl ether 600.7 g, 3,3′-diaminodiphenyl sulfone 670.2 g, bis-3-
(Aminopropyl) tetramethylsiloxane 74.6
g and the kettle was heated to 30 ° C. 30 minutes later,
644.4 g of 3 ', 4,4'-benzophenonetetracarboxylic dianhydride, pyromellitic dianhydride 64
1.3 g and 294.2 g of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride were added, and the kettle was heated to 58 ° C. After 3 hours, 11.8 g of maleic anhydride was added, and the mixture was further heated at 58 ° C for 1 hour to obtain a polyamic acid NMP solution (A1).

Using a homogenizer together with 4.6 g of carbon black, 24.0 g of polyamic acid solution (A1) and 61.4 g of N-methylpyrrolidone and 90 g of glass beads for 30 minutes at 7000 rpm,
The glass beads were removed by filtration to obtain a carbon black mill base.

Pigment Blue 15: 6 2.2
g, 24.0 g of polyamic acid solution (A1) and 63.8 g of N-methylpyrrolidone with 90 g of glass beads using a homogenizer at 7000 rpm for 30 minutes, followed by removing the glass beads by filtration to obtain a blue pigment mill base. .

By mixing all of the obtained mill bases in total, a paste for a resin black matrix was obtained.

A paste for a resin black matrix was spin-coated on an alkali-free glass substrate (0.7 mm in thickness), and dried at 50 ° C. for 10 minutes, at 90 ° C. for 10 minutes and at 110 ° C. for 20 minutes in an air using an oven. To obtain a polyimide precursor colored film having a thickness of 1.1 μm. A positive photoresist (OFPR-80 manufactured by Tokyo Ohka Co., Ltd.) is formed on this film.
0) and dried by heating at 80 ° C. for 20 minutes.
m was obtained. Canon UV exposure machine PL
Using A-501F, an ultraviolet ray having a wavelength of 365 nm and an intensity of 50 mJ / cm ² was irradiated through a chrome photomask. After the exposure, the substrate was immersed in a developing solution consisting of a 2.38 wt% aqueous solution of tetramethylammonium hydroxide to simultaneously develop the photoresist and the polyimide precursor colored film. After the etching, the unnecessary photoresist layer was stripped with methyl cellosolve acetate. Further, the thus obtained polyimide precursor colored film was heat-treated at 300 ° C. for 30 minutes in a nitrogen atmosphere to form a 0.9 μm-thick polyimide colored pattern film composed of grid-like pixel portions and frame portions surrounding them. Obtained.

(Formation of Colored Layer) Next, Pigment Red 177, Pigment Green 36, and Pigment Blue 15: 6 were prepared as red, green, and blue pigments, respectively.
It was mixed and dispersed with the polyamic acid solution (A1) to obtain three kinds of colored pastes of red, blue and green.

The obtained red paste was spin-coated on a resin black matrix substrate, and dried at 50 ° C. for 90 minutes.
The film was heated and dried in air using an oven at 110 ° C. for 10 minutes and at 110 ° C. for 20 minutes to obtain a 1.1 μm-thick polyimide precursor colored film. A positive photoresist (OFPR-800 manufactured by Tokyo Ohka Co., Ltd.) is applied on this film,
After drying for 1 minute, a resist film having a thickness of 1 μm was obtained. Ultraviolet light having an intensity of 50 mJ / cm @ 2 at a wavelength of 365 nm was irradiated through a chromium photomask using an ultraviolet exposure apparatus PLA-501F manufactured by Canon Inc. After exposure, 2.38 wt% of tetramethylammonium hydroxide
%, And the development of the photoresist and the polyimide precursor colored film was performed simultaneously.
After the etching, the unnecessary photoresist layer was stripped with methyl cellosolve acetate. Further, the thus obtained polyimide precursor colored film was heat-treated in a nitrogen atmosphere at 300 ° C. for 30 minutes to obtain a 0.9 μm-thick polyimide red pattern film stripe on the lattice portion of the black matrix.

Thereafter, similarly, a pattern of a green paste and a blue paste was formed to obtain a color filter having three primary colors of red, green and blue.

(Formation of Transparent Electrode Layer) After forming a transparent protective film for a color filter on the colored layer, ITO was formed by a sputtering method, and the film thickness was 1400 angstroms and the surface resistance was 15 Ω / □. there were.

In the color filters obtained as described above, the refractive index differences between the transparent protective film for the color filter and the colored layer, and between the transparent protective film for the color filter and the transparent conductive film were 0.09 and 0.09, respectively. And 0.1
It was one.

When the reflectance of the color filter is measured from the film surface side in the pixel portion (MCPD manufactured by Otsuka Electronics Co., Ltd.)
-2000, reference: BK-7), 7.6%. Furthermore, when a color liquid crystal display device was manufactured using the obtained color filter, no interference fringes were observed.

Example 2 A color filter was prepared in the same manner as in Example 1 except that no transparent electrode was provided.

In the obtained color filter, the difference in refractive index between the transparent protective film for a color filter and the colored layer was 0.09.

When the reflectance of the color filter was measured, it was 5.2%.

Further, when a color liquid crystal display device driven by a lateral electric field was manufactured using the obtained color filters, no interference fringes or uneven brightness were observed.

Example 3 When a color filter was prepared in the same manner as in Example 1, the thickness of the colored layers was all 1.8 μm, and a spacer was formed on the resin black matrix simultaneously with the formation of each colored layer. Color filters were created. In addition,
The formed spacer has a form in which three primary colors are stacked.

In the obtained color filter, the difference in refractive index between the transparent protective film for a color filter and the colored layer, and the difference in refractive index between the transparent protective film for a color filter and the transparent conductive film were as follows:
They were 0.09 and 0.11, respectively.

When the reflectance of the color filter was measured, it was 7.6%.

Further, when a color liquid crystal display device was manufactured using the obtained color filters, no interference fringes were observed.

Example 4 A transparent protective film for a color filter was obtained in the same manner as in Example 1, except that a ZrO ₂ methanol sol solution was used instead of the Sb ₂ O ₅ methanol sol solution. When the refractive index of the coating film thus produced was measured, it was 400 nm.
Was 1.65 at this wavelength.

Next, in the same manner as in Example 1, a color filter having the obtained transparent protective film for a color filter between the colored layer and the transparent electrode was prepared. As a result, the refractive index differences between the transparent protective film for a color filter and the colored layer and between the transparent protective film for a color filter and the transparent conductive film were 0.11 and 0.13, respectively.

When the reflectance of the color filter was measured, it was 8.8%.

Further, when a color liquid crystal display device was manufactured using the obtained color filters, no interference fringes were observed.

Comparative Example 1 A transparent protective film for a color filter was obtained in the same manner as in Example 1 except that the methanol sol solution of Sb ₂ O ₅ was not added. When the refractive index of the prepared coating film was measured, it was 400
It became 1.53 at the wavelength of nm.

Next, in the same manner as in Example 1, a color filter having the obtained transparent protective film for a color filter between the colored layer and the transparent electrode was prepared. As a result, the refractive index differences between the transparent protective film for a color filter and the colored layer and between the transparent protective film for a color filter and the transparent conductive film were 0.17 and 0.19, respectively.

When the reflectance of the color filter was measured, it was 15%.

Further, when a color liquid crystal display device was manufactured using the obtained color filter, interference fringes were observed.

Example 5 A transparent protective film for a color filter was obtained in the same manner as in Example 1 except that a TiO ₂ methanol sol solution was used instead of the Sb ₂ O ₅ methanol sol solution. When the refractive index of the coating film thus produced was measured, it was 400 nm.
At 1.67.

Next, in the same manner as in Example 1, a color filter having the obtained transparent protective film for a color filter between the colored layer and the transparent electrode was prepared.

As a result, the refractive index difference between the transparent protective film for a color filter and the colored layer, and the refractive index between the transparent protective film for a color filter and the transparent conductive film were 0.09 and 0.09 respectively.
It was 0.11.

When the reflectance of the color filter was measured, it was 7.6%.

Further, when a color liquid crystal display device was manufactured using the obtained color filters, no interference fringes were observed.

Example 6 A 20 L reactor equipped with a thermometer, a dry nitrogen inlet, a heating / cooling device using hot and cold water, and a stirring device was charged with N.
-Methylpyrrolidone (NMP) 11497.2 g,
4,3'-diaminodiphenylsulfone 44.7 g
(3.00 mol), m-phenylenediamine 29
2.0 g (2.70 mol) of bis-3- (aminopropyl) tetramethylsiloxane 74.6 g (0.30 mol)
mol), and the kettle was heated to 30 ° C. 30 minutes later,
1747.7 g (5.94 mol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride was charged, and the kettle was heated to 58 ° C. After 3 hours, phthalic anhydride 1
7.8 g (0.12 mol) was added, and the mixture was further heated at 58 ° C. for 1 hour to obtain a polyamic acid NMP solution. This polyamic acid solution was charged to a pore size of 0.2 μm
After filtration through a membrane filter, the mixture was applied on a glass substrate using a spin coater, and the solution was applied at 50 ° C. for 10 minutes.
Heat drying in air using a thermostat at 0 ° C. for 10 minutes and 110 ° C. for 20 minutes, and further heat-treating at 300 ° C. for 30 minutes in a nitrogen atmosphere. I got When the refractive index of this transparent protective film for a color filter was measured, it was found to be 400
It was 1.7 at a wavelength of nm.

Next, in the same manner as in Example 1, a color filter having the obtained transparent protective film for a color filter between the colored layer and the transparent electrode was prepared. As a result, the refractive index differences between the transparent protective film for a color filter and the colored layer, and between the transparent protective film for a color filter and the transparent conductive film were 0.05 and 0.07, respectively.

When the reflectance of the color filter was measured, it was 6.0%.

Further, when a color liquid crystal display device was manufactured using the obtained color filters, no interference fringes were observed.

Example 7 5 g of an NMP solution of the polyamic acid prepared in Example 6
Sb ₂ O ₅ methanol sol solution with a solid concentration of 30%
5 g were added. From this solution, a heat treatment was performed in the same manner as in Example 5 to obtain a transparent protective film for a color filter. The refractive index of this transparent protective film for a color filter was 1.75 at a wavelength of 400 nm.

Next, in the same manner as in Example 1, a color filter having the obtained transparent protective film for a color filter between the colored layer and the transparent electrode was prepared. As a result, the refractive index differences between the transparent protective film for a color filter and the colored layer and between the transparent protective film for a color filter and the transparent conductive film were 0.03 and 0.05, respectively.

When the reflectance of the color filter was measured, it was 5.2%.

Further, when a color liquid crystal display device was manufactured using the obtained color filter, no interference fringes were observed.

[0113] Example _{8 Ti (OCH (CH 3)} 2) of acetylacetone 4.5g was added to ₄ 5 g, from the titanium acetylacetonate, pure water was added 0.5 g. The above solution was added to 5 g of an NMP solution of polyamic acid obtained in the same manner as in Example 6. From this solution, a transparent protective film for a color filter was obtained in the same manner as in Example 6. When the refractive index of this transparent protective film for a color filter was measured, it was 400 n.
It was 1.77 at a wavelength of m.

Next, in the same manner as in Example 1, a color filter having the obtained transparent protective film for a color filter between the colored layer and the transparent electrode was prepared. As a result, the refractive index differences between the transparent protective film for a color filter and the colored layer and between the transparent protective film for a color filter and the transparent conductive film were 0.02 and 0.04, respectively.

When the reflectance of the color filter was measured, it was 4.5%.

Furthermore, when a color liquid crystal display device was manufactured using the obtained color filter, no interference fringes were observed.

Example 9 Ethyl acetoacetate was added to ₅ g of Ta (OC ₂ H ₅ ) _5.
6 g was added to make tantalum ethyl acetoacetate, and then 0.5 g of pure water was added. The above solution was added to 5 g of an NMP solution of polyamic acid obtained in the same manner as in Example 6. From this solution, a transparent protective film for a color filter was obtained in the same manner as in Example 5. When the refractive index of the transparent protective film for a color filter was measured, it was 400 nm.
Was 1.74 at the wavelength of.

Next, in the same manner as in Example 1, a color filter having the obtained transparent protective film for a color filter between the colored layer and the transparent electrode was prepared. As a result, the refractive index differences between the transparent protective film for a color filter and the colored layer and between the transparent protective film for a color filter and the transparent conductive film were 0.06 and 0.08, respectively.

When the reflectance of the color filter was measured, it was 7.0%.

Furthermore, when a color liquid crystal display device was manufactured using the obtained color filter, no interference fringes were observed.

Example 10 Ethyl acetoacetate was added to 5 g of Zr (OC ₂ H ₅ ) _4.
Then, 7.2 g of zirconium ethyl acetoacetate was added, and then 0.6 g of pure water was added. The above solution was added to 5 g of an NMP solution of polyamic acid obtained in the same manner as in Example 6. From this solution, a transparent protective film for a color filter was obtained in the same manner as in Example 6. When the refractive index of the transparent protective film for a color filter is measured,
It became 1.73 at a wavelength of 400 nm.

Next, in the same manner as in Example 1, a color filter having the obtained transparent protective film for a color filter between the colored layer and the transparent electrode was prepared. As a result, the refractive index differences between the transparent protective film for a color filter and the colored layer and between the transparent protective film for a color filter and the transparent conductive film were 0.07 and 0.09, respectively.

When the reflectance of the color filter was measured, it was 7.8%.

Further, when a color liquid crystal display device was manufactured using the obtained color filters, no interference fringes were observed.

Example 11 Hf (OCH ₂ CH ₂ CH ₂ CH ₃ ) _{4 having a} solid concentration of 47%
5 g of the above solution was added to 5 g of an NMP solution of polyamic acid obtained in the same manner as in Example 6. However, the strictly dehydrated NMP used here was used. From this solution, a transparent protective film for a color filter was obtained in the same manner as in Example 6. The refractive index of the transparent protective film for a color filter was 1.74 at a wavelength of 400 nm.

Next, in the same manner as in Example 1, a color filter having the obtained transparent protective film for a color filter between the colored layer and the transparent electrode was prepared. As a result, the refractive index differences between the transparent protective film for a color filter and the colored layer and between the transparent protective film for a color filter and the transparent conductive film were 0.06 and 0.08, respectively.

When the reflectance of the color filter was measured, it was 7.0%.

When a color liquid crystal display device was manufactured using the obtained color filters, no interference fringes were observed.

Example 12 γ-aminopropylmethyldiethoxysilane 191.
5 g of 3-methyl-3-methoxybutanol 414.
To a mixed solution of 7 g and 414.7 g of γ-butyrolactone, 161.0 g of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride was added while stirring at 30 ° C. The mixture was stirred for 2 hours to obtain a polyimidesiloxane precursor solution.

Next, in the same manner as in Example 1, a color filter having a transparent protective film for a color filter between the colored layer and the transparent electrode was prepared using the polyimidesiloxane precursor solution. Here, the thickness of the transparent protective film for a color filter was 0.01 μm, and the heating conditions were 100 ° C. for 5 minutes and 280 ° C. for 30 minutes. When the reflectance of the obtained color filter was measured, it was 8.5%.

Here, the transparent protective film for a color filter obtained from the used polyimide siloxane precursor solution has a refractive index of 1.54 at a wavelength of 400 nm. Is getting smaller.

Further, when a color liquid crystal display device was manufactured using the obtained color filter, no interference fringes were observed.

Comparative Example 2 A color filter was prepared in the same manner as in Example 12, except that the thickness of the transparent protective film for a color filter was changed to 0.05 μm. When the reflectance of the obtained color filter was measured, it was 15.8%.

Further, when a color liquid crystal display device was manufactured using the obtained color filter, interference fringes were observed.

[0135]

The color filter using the transparent protective film for a color filter according to the present invention and the liquid crystal display device can suppress the occurrence of display defects and interference fringes caused by uneven cell gaps.

Claims (16)

[Claims] 1. A transparent protective film for a color filter, having a refractive index in the range of 1.55 to 1.8. 2. The transparent protective film for a color filter according to claim 1, comprising ultrafine oxide particles. 3. The transparent protective film for a color filter according to claim 1, wherein a thermosetting resin solution composition containing a metal alkoxide is used. 4. The transparent protective film for a color filter according to claim 1, wherein a polyimide is contained as a resin component. 5. A color filter comprising at least a black matrix, a coloring layer composed of three primary colors, and a transparent protective film, wherein the transparent protective film for a color filter according to claim 1 is used. A color filter characterized by the following. 6. A black matrix comprising at least a colored layer of three primary colors, a plurality of dot-shaped spacers formed by laminating colored layers of three primary colors on a part of the black matrix, and a transparent protective film. A color filter, wherein the transparent protective film for a color filter according to any one of claims 1 to 4 is used. 7. The method according to claim 5, wherein the transparent electrode layer is provided on the coloring layer via a transparent protective film layer.
The color filter according to any one of the above. 8. The color filter according to claim 5, wherein an alignment film is provided on an uppermost layer. 9. The color filter according to claim 5, wherein the black matrix is obtained by dispersing a light-shielding agent in a resin. 10. The color filter according to claim 5, wherein the resin component of the black matrix or the colored layer is made of polyimide. 11. The color filter according to claim 5, wherein a difference in refractive index between the colored layer and the transparent protective film layer for a color filter is in the range of 0.005 to 0.15. . 12. The color filter according to claim 7, wherein the difference in refractive index between the transparent electrode layer and the transparent protective film layer for a color filter is in the range of 0.005 to 0.15. 13. A color filter, wherein the reflectance of the pixel portion on the film surface side of the color filter is 10% or less. 14. A color filter in which the reflectance of the pixel portion on the film surface side of the color filter is 10% or less, wherein the transparent protective film for a color filter according to claim 1 is further formed. A color filter, characterized in that: 15. A liquid crystal display device using the color filter according to claim 5. Description: 16. The liquid crystal display device according to claim 15, wherein the liquid crystal is driven by a thin film transistor.