JPH02244005A - Production of color filter - Google Patents

Abstract

PURPOSE:To improve the uniformity of a resin layer and to decrease a color filter materials for foaming the colored patterns by repeating a stage for forming patterns by transferring a colored photosensitive dry film formed from a photosensitive resin which allows the transmission of light of a specific wavelength region and a coloring material onto a substrate and thereby forming the color filters. CONSTITUTION:A colored photosensitive resin soln. contg. the photosensitive resin having >=80% light transmittance in the entire region of 400 to 700nm (visible light region) when the resin is made into a film and the coloring material is prepd. and is made into the film to form the colored film; thereafter, the colored film is transferred by a vacuum lamination method onto the glass substrate. The colored patterns are formed by using the techniques of photolithography (pattern exposing, developing and drying) and the prescribed patterns of red, green and blue layers are formed by repeating this stage, following which a transparent conductive film and polyimide oriented film are successively formed to form the color filters. The color filters which are formed without unequal coating, are uniform in film thickness and are economical formed in this way.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for manufacturing a color filter.

More specifically, LCD televisions, color displays, color solid-state AM devices such as COD and 803, l
This invention relates to a method for manufacturing a color filter suitable for fine color separation filters used in 1lIII tubes and the like.

[Prior Art] Conventionally, this type of color filter has been specially selected.

First, a photosensitive resin layer is formed by coating a photosensitive 1i [1 solution made of gelatin or casein with dichromate added thereto on a transparent substrate such as glass, and a mosaic or striped pattern is formed by exposure and development. form. Next, this pattern portion is colored by a dyeing method using a dye having predetermined 1-spectral characteristics. Next, a color stain prevention film (intermediate layer) is formed on the colored resin film thus formed, or a color stain prevention treatment is applied to the colored resin film, and then a photosensitive layer of 114 m is applied in the same manner on top of the colored resin film. pattern is formed and dyed with another dye to form a colored resin film. Further, if necessary, the operation for forming a colored resin film is repeated to form a desired plurality of layers of colored resin films, and finally, a back protective film is attached to complete the formation of a color filter.

The manufacturing process of the general photosensitive liquid LFL as described above includes the following steps:
There is a pressure filtration process using air or nitrogen, and the photosensitive resin has a high viscosity. For this reason, surrounding gas is easily taken in during handling, and the photosensitive resin solution contains a considerable amount of dissolved gas.

Further, the photosensitive resin solution is dropped onto a substrate such as glass using a spinner to form a coating film.

At this time, the wettability of the substrate such as glass and the photosensitive resin solution is poor, and a large amount of the photosensitive resin solution is required for the photosensitive resin layer to be formed.

[Problems to be Solved by the Invention] For this reason, even if a coating film is formed by the above-mentioned spin code method, it is difficult to obtain a photosensitive resin layer having a film thickness with excellent uniformity. At the same time, a water-soluble photosensitive resin solution consisting of gelatin or casein and dichromic acid has poor wettability on a glass substrate, and even when a large amount of resin solution is used, air bubbles may be trapped during application. This tends to cause uneven coating.

Further, since the glass substrate has a rectangular shape different from that of the wafer, the film thickness becomes thick at some corners of the substrate, which causes a decrease in uniformity and narrows the effective area of the substrate. The problems of uniformity and amount used become more disadvantageous as the substrate size increases, and are a major problem in improving the quality and cost of color filters that can be obtained.

On the other hand, JP-A-63-37304 discloses a method of applying a polyimide resin containing an Ia pigment using a roll coater as a method for eliminating uneven film thickness. Even in this method, since the polyimide resin does not have photosensitivity, it is necessary to add a photolithography step for pattern formation, which lengthens the color and filter manufacturing steps. Furthermore, there is a problem in that photosensitivity instability remains in the pattern forming process in practice.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present inventors developed a dry film resist (M. Nakano, [Adhesion J Volume 3G,
5 @, pp. 212-22G (1986)),
A color filter that provides a photosensitive resin layer with excellent uniformity, reduces the amount of photosensitive resin used, improves economic efficiency, and is advantageous for larger substrates! The purpose is to obtain the l method.

The present invention comprises (a step of preparing a spring color photosensitive resin solution containing a photosensitive resin that transmits light in a wavelength range of at least 400 to 700 rv and a coloring material, and forming a film from the resin solution, (b> It consists of a step of transferring a colored photosensitive dry film onto a substrate and (c) a step of forming a pattern on the film by photolithography, and forming a colored pattern on the substrate by repeating steps (a) to (c). The present invention relates to a method for manufacturing a color filter characterized by:

[Function] According to the method for producing a color filter of the present invention, a colored photosensitive dry film is used, and by vacuum lamination or the like,
Since the film is transferred onto a substrate and a colored pattern of a predetermined size is formed by photolithography, it is possible to improve the uniformity of the resin layer and reduce the amount of color filter material required to form the colored pattern.

[Example 1] In C1 of the present invention, first, a colored photosensitive resin solution containing a photosensitive resin and a coloring material is prepared.

Transparent resins are widely used as the photosensitive resin, but colored resins have a light transmittance of 80% or more, more preferably 95% or more, in the entire range of 400 to 700 na+ (visible light region) when formed into a film. Increase image transparency,
This is preferable from the standpoint of obtaining a color filter with excellent brightness.

Specific examples of the photosensitive resin include compounds shown in the following (A) to (c).

(A) Oils such as water-soluble resins such as polyvinyl alcohol/stilbazolium, photocrosslinkable resins such as cinnamic acid, photodegradable crosslinkable resins such as bisazide, and photodegradable polarity changeable resins such as 0-quinonediazide. Soluble resin (B) Combination of the following binder resin (a) and photocrosslinking agent (b) (Binder resin: (1) Animal protein-based such as gelatin, casein, glue, etc. C) Carboxymethyl hydroxyethyl cellulose cypropyl cellulose, Cellulosics such as methyl cellulose; Vinyl polymerization systems such as polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl methyl ether, polyacrylic acid, polyacrylamide, polydimethylacrylamide, and their copolymers; Ring-opening polymerization of polyethylene glycol, polyethyleneimine, etc. System (V) Condensation systems such as water-soluble nylon, butyral resins, styrene-maleic acid copolymers, chlorinated polyethylene or chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymers, polyvinyl acetate, acrylic resins , polyamides, polyesters, phenolic resins, polyurethane resins, and other oil-soluble resins (1) Photocrosslinking agents: dichromates, chromates, diazo compounds, bisazide compounds, etc. (c) (B) (-(1) Combination V of binder resin and monomer or oligomer (/N and initiator←)
~ Monomer or oligomer: acrylic acid, methacrylic acid, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-
Hydroxypropyl methacrylate, vinyl acetate, N-vinylpyrrolidone, acrylamide, methacrylamide, hydroxymethylacrylamide, N-(1
．． 1-dimethyl-3-oxobutyl)acrylamide,
Polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, methylene bisacrylamide, 1,3.

5-Triacryloyl-1,3.5-triazacyclohexane, pentaerythritol triacrylate, styrene, vinyl acetate, various acrylic esters, various methacrylic esters, acrylonitrile, etc.) l17Q initiator: (1) Photodecomposition type initiators, such as azobisisobutyronitrile, benzoin alkyl ethers, thioacridone, benzyl, t[alkylsulfonyloxymide, 2, 4. 6-Tri[trichloromethyl-1-triazine, etc. C) Hydrogen transfer type initiators, such as benzophenone, anthraquinone, 9-phenylacridine, etc. @ Electron transfer type complex initiators, such as benzanthrone/triethanolamine, methylene blue/benzenesulfinate , triallylimidazolyl dimer/Michler's ketone, carbon tetrachloride/manganese carbonyl, etc. The coloring material used is a colored powder that is sparingly soluble in water or an organic solvent, and may be either an organic pigment or an inorganic pigment. . Furthermore, dyes that are poorly soluble in water or organic solvents can also be used.

The pigments include azo lake type, insoluble azo type,
Condensed azo series, phthalocyanine series, quinacridone series, dioxazine series, isoindolinone series, anthraquinone series,
Perinone type, thioindico type, perylene type, mixtures thereof, etc. can be used.

Examples of the inorganic pigments include Milolipur, yellow lead, cadmium yellow, yellow iron oxide, lime permillion, iron oxide,
Red rose, cadmium red, antimony vermilion, cobalt purple, manganese pigment, ultramarine blue, navy blue, cobalt blue, cerulean blue, chrome green, zinc green, viridian, emerald green, cobalt green, and mixtures thereof are used.

As the dye, Kayanor Milling Red RS (c, 1, ^cid Red 114.
Brilliant Indoal-5G (c, 1, Ac1d Blue 103. manufactured by Hoechst Co., Ltd.) as a green dye;
, 1, Ac1dYellOW 42. Kayanolcyanine 6 as a blue dye
Examples include B (c, 1, Ac1dBlue 32. Japanese top medicine ■chin).

Various additives may be further added to the colored photosensitive resin solution used in the present invention.

Next, the obtained colored photosensitive resin solution is formed into a film to produce a colored photosensitive dry film (hereinafter also referred to as colored film).

Although there are no particular limitations on the method for forming a film, for example, a colored film can be formed by forming the colored photosensitive resin solution on a base film by a known method such as an O-lu coating method or a curtain coating method. The thickness of the colored film is usually 1 to 25 mm. It is about m. Note that as the base film, a film such as polyethylene terephthalate or polyethylene is usually used.

At this time, the color characteristics of the colored film are determined by the type of photosensitive resin used as the binder polymer, the type of coloring material dispersed in the photosensitive resin, the amount of dispersion thereof, the thickness of the colored film, etc.

As for the color characteristics, the absorption region and the transmission region change depending on the type of coloring material used, but it is preferable that the light transmittance in the absorption region is 20% or less, generally 10% or less, and at the same time, the light transmittance in the transmission region is preferably 10% or less. It is preferable that the transmittance is 40% or more, more preferably 60% or more.

Next, the colored film is transferred onto a substrate such as glass.

The transfer is performed using the vacuum lamination method, which prevents air from entering between the substrate and the colored film.
This is preferable from the viewpoint of preventing adhesion of foreign matter. As a substrate,
Examples include glass substrates and silicon wafers.

A pattern is then formed on the transferred film by photolithography.

As the photolithography method, a conventional method is used in which a transferred film is pattern-exposed using a photomask and an exposure device, and then unnecessary portions are removed using a developer.

By repeating the above steps to form a desired pattern of multiple layers on the substrate, a color filter in which a colored pattern having desired color characteristics is formed can be obtained.

Next, one embodiment of the method of the present invention will be described with reference to FIGS. 1 to 3, but the present invention is not limited to this embodiment.

Example 1 FIG. 1 is a process diagram showing an outline of a method for producing a color filter according to the present invention. As shown in Fig. 1, in this example, a colored photosensitive resin solution having a predetermined composition was prepared, and then this resin fill was made into a film to make a colored film, and then vacuum laminated onto a glass substrate. The colored film was transferred by. Next, a colored pattern was formed using photolithography technology (pattern exposure, development, and drying). After repeating this process to form predetermined patterns in red, green, and blue, a transparent electrode film and a polyimide alignment film were sequentially formed to obtain a color filter.

This will be explained in detail below.

First, Lake Red C (red pigment manufactured by Dainichiseika Chemical Industry Co., Ltd.)
1 part of the liquid was mixed with 10 parts of a 30% by weight aqueous solution of polyvinyl alcohol (average degree of polymerization 500, degree of saponification 80 mol%), and 3 parts of a liquid obtained by mixing 1 part of polyvinyl alcohol (average degree of polymerization 450, degree of saponification 88 mol%). %) and 10 parts of a photosensitive resin containing 6% by weight of p-formylstylpyridine based on polyvinyl alcohol were thoroughly mixed to prepare a red photosensitive resin/resin solution.

Then, the film thickness was 25. This resin solution was dropped onto the polyethylene terephthalate film (1) by a curtain coater method and dried at 10°C for 1 hour to form a red photosensitive resin layer (3) with a thickness of 5 mm. Furthermore, this upper layer has a film thickness of 2
A polyethylene film [2] with a thickness of 5 mm was formed to obtain a rolled red dry film having a width of 600 m and a length of 120 m as shown in FIG.

Next, using the obtained red dry film, a red photosensitive resin layer was formed by vacuum lamination on a 400 em0 glass substrate (4) on which a light-shielding pattern was previously formed by Cr coating, as shown in Fig. 3. (3) and a polyethylene film (R), red photosensitive resin 11 (3) was formed on the substrate (4), and a polyethylene film ('2J) was formed on top of the red photosensitive resin 11 (3). Indicates the direction in which the board is sent.The board temperature at this time is 5
0℃, lamination conditions are temperature 80℃, pressure 2 K9/
ci, speed 1.5 m/min F av L.

Next, after precise positioning was performed through a mask, a predetermined pattern exposure was performed using an 11V high-pressure mercury lamp. Next, the pattern-exposed red dry film was spray developed with a water/isopropyl alcohol-271 developer to selectively remove the non-exposed areas, and then heated at 200°C for 1
A red pattern was formed by heating for a period of time. Although the light transmittance of this red image was less than 1% at 5600 m or less, the light transmittance at 60001 m or more was more than 90%, and a colored pattern with a film thickness of 5 mm was uniformly formed over the entire substrate. .

Next, add 1 part of Lionol Green 2"/-301 (a green pigment manufactured by Toyo Ink Manufacturing ■) to polyvinyl alcohol (
30% by weight of average polymerization degree SOO, saponification degree 80 mol%)
3 parts of the solution obtained by mixing with 9 parts of an aqueous solution and a 30% aqueous solution of polyvinyl alcohol (average degree of polymerization 450, degree of saponification 88 mol%) contain 6% p-formylstylpyridine based on the polyvinyl alcohol. Introduced photosensitive resin 1
A green photosensitive resin solution consisting of 0 parts was prepared and treated in the same manner as above to form a green pattern on a red pattern. This green image is 600-700n
Although the light transmittance of m is less than 1%, 500
The light transmittance at ~560 n- was 80% or more, and the film had a uniform colored pattern with a thickness of 5 mm.

Next, 1 part of Fustogen Blue GNFS (a blue pigment manufactured by Dainippon Ink and Chemicals) and 10 parts of a 30% by weight aqueous solution of polyvinyl alcohol (average degree of polymerization 500, degree of saponification 80 mol%) were mixed. 3 parts of the obtained liquid and polyvinyl alcohol (average degree of polymerization 450, degree of saponification 80 mol%)
) A blue photosensitive resin solution was prepared by introducing 6% by weight of p-formylstylpyridine based on polyvinyl alcohol into a 30% aqueous solution of 10% photosensitive resin, and using this solution, the same treatment as above was carried out. A blue pattern was formed on the green pattern. This blue image is 560-700r
Although the light transmittance of v is less than 1%, 440
The light transmittance at ~520 nm was 85% or more, and the film had a uniform colored pattern with a thickness of 5 mm.

A transparent conductive film was formed on the colored image obtained in this manner to a thickness of 800 OA by low-temperature sputtering, and then a polyimide film was coated thereon to a thickness of 100 OA. Perform rubbing treatment and face
Combined with a thin film transistor that serves as the R pole. Next, a cell was assembled by injecting liquid crystal, and when applied to a full-color liquid crystal display device in which a colored image was formed inside the cell, excellent characteristics were obtained.

In Example 1, a water-soluble photosensitive resin was used as the photosensitive resin for the colored film, but an oil-soluble photosensitive resin as described above may also be used. Further, in Example 1, a pigment was used as the coloring material, but a dye may also be used. There is no need to limit the usage amount of each component to the usage amount in Example 1, and the numerical value may be determined as appropriate in consideration of necessary color characteristics, patternability, etc. There is no problem in forming a film from the resin solution using other methods such as roll coating. The substrate does not need to be limited to a glass plate, and can also be applied to a wafer. Note that, in view of the step of transferring a dry film onto a substrate by vacuum lamination, the effects of the present invention are most exhibited when applied to large substrates.

[Effects of the Invention] As described above, according to the production method of the present invention, since a colored photosensitive dry film is used, a color filter can be economically produced without uneven coating and with a uniform film thickness.

Furthermore, since patterning is performed by photolithography, it is possible to change color filters with excellent alignment and pattern accuracy.

[Brief explanation of drawings]

FIG. 1 is a process diagram showing an outline of the manufacturing method of Example IM1, FIG. 2 is a schematic diagram of a spring color photosensitive dry film, and FIG. 3 is an explanatory diagram of a vacuum laminator. (Main symbols on the drawing) G): Red photosensitive resin layer (4): 1 Board agent Masuo Oiwa

Claims (1)

[Claims] (1) (a) A step of preparing a colored photosensitive resin solution containing a photosensitive resin that transmits light in a wavelength range of at least 400 to 700 nm and a coloring material, and forming the resin solution into a film; and (c) forming a pattern on the transferred film by photolithography. The steps (a) to (c) are repeated to color the substrate. A method for producing a color filter characterized by forming a pattern.