JPH08136716A - Production of color filter - Google Patents

Abstract

PURPOSE: To provide a producing method for a color filter which does not generate color unevenness which deteriorates a display quality of color liq. crystal display. CONSTITUTION: In the producing method for color filter in which a black matrix 1, a colored picture element 3 and an overcoat film 4 are formed on a transparent substrate such as transparent plastic or glass and in a forming stage of the colored picture element, after forming a colored photosensitive resin film on the transparent plastic or the glass substrate 2 by using a roll laminator, the material is heat treated at a temp. in which a protective film is shrunk by heat.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a color filter used in a color liquid crystal display device.

[0002]

2. Description of the Related Art Liquid crystal display (hereinafter abbreviated as LCD)
Taking advantage of its thinness, small size, and low power consumption, is currently used for display parts of watches, calculators, TVs, personal computers and the like. Furthermore, in recent years, color LCDs have been developed and OA / AV
It has begun to be used in many applications such as navigation systems and viewfinders mainly for devices, and the market is expected to expand rapidly in the future.

A color filter for displaying an LCD in color is R (red) on a substrate 2 such as a glass plate on which a BM (black matrix) 1 having a grid pattern is formed.
Color pixel 3 consisting of G (green) and B (blue) (approximately 100 x 1
(00 × 2 μm), and a transparent overcoat layer (OC) 4 is formed thereon. Reference numeral 5 is a polarizing plate, and 6 is an ITO electrode.

A color LCD has a color filter 7 as an LC.
The display screen can be colored by being installed inside D and transmitting the backlight light to the color filter. 8 is an alignment film, 9 is a liquid crystal, 10 is a seal material, 11 is a top coat layer, 12 is an ITO electrode, 13 is a substrate such as a glass plate, 14
Is a polarizing plate.

At present, color filters are mainly manufactured by the dyeing method. However, in this method, it is necessary to repeat the process of applying a transparent photosensitive resin on a glass substrate, forming pixels by drying, exposing and developing, dyeing with a dye, and then forming a color mixing prevention layer three times. Therefore, the number of steps is large and the cost is high. Further, since a dye is used as a colorant, there is a drawback that the reliability (weather resistance / heat resistance), which is an important subject of the color filter, is deteriorated.
Therefore, some color filters using a pigment as a colorant have been proposed, and among them, there are an electrodeposition method, a printing method, and a photolithography method (photolithography method).

However, the electrodeposition method requires the formation of an electrode pattern (1) the degree of freedom of the pattern is small,
(2) The cost is high, and the printing method has problems that (1) it is difficult to align a large-sized substrate and the resolution is low, so it is difficult to miniaturize, and (2) the flatness of the pattern is poor. The photolithography method is considered to be the mainstream. A liquid resist and a film are considered for the photolithography method. In the liquid resist, color pixels are formed by applying a varnish in which a pigment is dispersed in a photosensitive resin on a glass substrate with a spinner, drying, exposing, and developing. On the other hand, the film is a varnish formed into a film like the photosensitive film for printed boards, and after being laminated on a substrate, color pixels are formed by exposure and development.

[0007]

In a method of manufacturing a color filter for a color liquid crystal display device using a film method, when a colored photosensitive resin film is transferred onto a transparent substrate by using a roll laminator, it is heated and pressed to Fine color unevenness occurs on the resin film. The present invention provides a method for manufacturing a color filter in which "color unevenness" that deteriorates the display quality of a color liquid crystal display device does not occur.

[0008]

The present invention is a method for producing a color filter in which a black matrix, colored pixels, and an overcoat film are formed on a transparent substrate such as a transparent plastic or glass substrate. In the step, a colored photosensitive resin film is formed on a transparent plastic or glass substrate by using a roll laminator, and then heat treatment is performed at a temperature at which the protective film thermally shrinks. By doing so, color unevenness on the surface disappears, and a color filter having no variation in color characteristics can be obtained. The temperature for heat treatment at the temperature for heat shrinkage is appropriately selected depending on the film.

[0009]

EXAMPLE 2-2'-bis [4-methacryloxy, polyethoxyphenyl] propane 35 parts by weight, γ-chloro-
15 parts by weight of β-hydroxypropyl-β'-methacryloyloxyethyl-o-phthalate, methacrylic acid / ethyl acrylate / ethyl acrylate (18/30 /
53 parts by weight) 50 parts by weight of copolymer resin, 1,7 bis (9-
2 parts by weight of acridinyl) heptane, hexamethoxymethylmelamine, methylethylketone, anthraquinone (red), halogenated copper phthalocyanine (green), and copper phthalocyanine (blue) were homogenized to obtain a photosensitive resin layer coating solution. The solution was applied onto a polyethylene terephthalate film having a thickness of 6 μm by a gravure coating machine (manufactured by Hirano Seiki Co., Ltd.)
Then, a 30 μm polyethylene film is bonded as a protective film to obtain a photosensitive film. The thickness of the photosensitive resin layer was 1.5 μm. Next, a glass substrate (1.1 mm × 20) with a chrome film (film thickness 0.1 μm)
0 mm x 300 mm, manufactured by Geomatic Co., Ltd.), using a roll laminator HLM1500 (manufactured by Hitachi Chemical Techno Plant Co., Ltd.) on a glass substrate on which a black matrix is formed, substrate temperature 110 ° C, roll temperature 140 ° C, roll pressure 6 kg / cm ² , The colored photosensitive resin was laminated so as to face the substrate while peeling off the photosensitive film at a speed of 0.2 m / min. The substrate in which glass substrate / colored photosensitive resin layer / polyethylene terephthalate was laminated in this order was heated on a hot plate at 130 ° C. for 5 minutes. Next, a parallel light exposure device M is passed through a predetermined negative mask.
1 using AP1200L (manufactured by Dainippon Screen)
00 mJ / cm ² exposure, then remove polyethylene terephthalate film, spray developing device DVW91
0.2 at 25 ° C. using 1 (manufactured by Dainippon Screen Co., Ltd.)
Spray developing with a weight% Na2 B2 O5 aqueous solution for 20 seconds to remove the unexposed portion, and clean oven CSO-402
(Kusumoto Kasei Co., Ltd.) is heated to 150 ° C. and cured to form a single colored pattern. This coloring formation process is performed by R, G,
Repeatedly using the film of each color in order of B, RGB
A pixel pattern is formed. Table 1 shows the results of the heat treatment and the color unevenness evaluation.

[0010]

[Table 1] ───────────────────────────── Heating temperature / ℃ Heating time / min Evaluation of color unevenness ────── ─────────────────────── A (None) (None) × B 80 5 × C 130 3 ○ D 130 5 ◎ E 150 5 Not developable ─ ────────────────────────────

[0011]

According to the present invention, a color filter in which color unevenness on the surface disappears and color characteristics do not vary can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view of a liquid crystal display.

[Explanation of symbols]

 1. BM (black matrix) 2. Glass substrate 3. Color pixel 4. Overcoat layer (OC) 5. Polarizing plate 6. ITO electrode 7. Color filter 8. Alignment film 9. Liquid crystal 10. Seal material 11. Top coat layer 12. ITO electrode 13. Glass substrate 14. Polarizer

Front Page Continuation (72) Inventor Ken Yoshida 48, Wadai, Tsukuba City, Ibaraki Hitachi Chemical Co., Ltd. Tsukuba Development Laboratory

Claims (1)

[Claims] 1. A black matrix on a transparent substrate,
Colored pixel, a method of manufacturing a color filter to form an overcoat film, after forming a film of a colored photosensitive resin film on a transparent substrate using a roll laminator, exposure,
Development is repeated for each color, only the last pixel is formed into a film using a colored photosensitive resin liquid, and the entire surface is exposed from the substrate side, which is the back surface of the pixel formation surface, to form colored pixels in a multicolor pattern. And method of manufacturing color filters.