JPH04335321A - Production of color display device - Google Patents

Abstract

PURPOSE:To provide the color display device which does not generate light leakage by adopting inexpensive color filters having light shielding films possessing a high light shielding property. CONSTITUTION:This process consists of a 1st stage for forming the color filter 3 on a glass substrate 1, a 2nd stage for forming org. films 4 between the color filters 3 by a rear surface exposing method, a 3rd stage for forming a transparent conductive thin film 5 on the color filters 3, a 4th stage for forming a metallic film 6 on the transparent conductive thin film 5, and a 5th stage for patterning the metallic film 6. The inexpensive multicolor display device which is improved in the light shielding property and has high quality is supplied in this way.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a color display device using color filters, and more particularly to a method for manufacturing a matrix type color display device using TFTs and color filters.

0002

2. Description of the Related Art In recent years, color display devices using liquid crystals have been used in so-called pocket televisions and the like, but the trend is rapidly toward larger sizes and larger screens. With the development of active drive elements such as TN liquid crystals and STN liquid crystals and TFTs, products with image quality approaching that of CRTs have been commercialized. Various studies are being conducted to improve the image quality and productivity of color display devices using TFTs, and one of the important technologies is the problem of color filters.

[0003] Color filter manufacturing methods include a dyeing method in which gelatin, which is a dyeable resin, is patterned and dyed using a dye, a printing method in which color ink is transferred and printed on a glass substrate by offset printing, etc. There are polymer electrodeposition methods in which a polymer resin and pigment are co-deposited on a transparent electrode by electrophoresis, and pigment dispersion methods in which a colored resist in which pigments are dispersed in a photosensitive resin is used to form a pattern by photofabrication. .

[0004] When using any of the color filters, a light-shielding film called a black matrix is required to prevent light leakage from the TFT and to improve image quality (apparent contrast). There are mainly three methods for producing black matrix. This will be explained below using the drawings.

FIG. 2 shows a conventionally known method for manufacturing a multicolor display device. Color filter 2R, 2G,
Black matrix 22 made of metal film in the gap between 2B
FIG. This is a black matrix 22 that is formed by forming a metal film on a glass substrate by sputtering or the like and then patterning it through various steps of photofabrication.

Thereafter, red, green, and blue color filters 2R, 2G, and 2B are sequentially formed, and a protective film 23 and a transparent electrode 24 are provided. FIG. 3 is a cross-sectional view showing a black matrix formed by photofabrication using a conventionally known resist in which a black pigment is dispersed in a photosensitive resin.

After sequentially forming the color filters 3R, 3G, and 3B, the black matrix 32 is formed, or
Alternatively, there is a method of forming the color filter after forming the black matrix 32. After that, the protective film 33 and transparent electrode 34 are sequentially provided in the same manner. FIG. 4 shows a color filter 4R in a part where a conventionally known black matrix is formed.
This shows a method of sequentially overlapping 4G and 4B.

Of course, the order in which the color filters are formed is arbitrary.

[0009]

[Problems to be Solved by the Invention] Recently, however, in TFT type LCDs, which are considered to have a promising future, it is required to improve the light shielding rate of the light shielding film in order to prevent light leakage from the switching elements. Furthermore, in order to improve image quality, it is desirable that the pattern of the light-shielding film be a grid. However, in the conventional manufacturing method, since the black pigment is dispersed in the resist, there is a limit to the amount added, and the required light blocking rate cannot be obtained. Furthermore, since the light-shielding film is formed by exposure from the back side of the substrate using the colored layer as a mask, there is a problem in that it is difficult to form the light-shielding film in a lattice shape.

SUMMARY OF THE INVENTION An object of the present invention is to solve these conventional problems and provide a method for manufacturing a color pattern having a light shielding film that has a high light shielding rate and can be formed into any desired pattern shape.

[0011]

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a method for manufacturing a color pattern, including a step of forming a color filter on a glass substrate, a step of forming an organic film between the color filters, and a step of forming a color filter on a glass substrate. By forming a transparent conductive film on top, a process of forming a metal film on the transparent conductive thin film, and a process of forming a pattern on the metal film by photofabrication, a high light shielding rate and an arbitrary pattern shape can be achieved. This makes it possible to manufacture a color pattern with a light-shielding film.

0012

[Operation] In the method for producing a color pattern configured as described above, a photosensitive resin is exposed and developed between the color filters, resulting in a color display device with good flatness and excellent image quality with excellent liquid crystal orientation. is obtained. Usable photosensitive resins include negative type polyester acrylate, polyester polyacrylate, epoxy acrylate, urethane acrylate, silicone acrylate, polybutadiene acrylate, photo-Michael addition type (polyene-thiol type) oligomer, photo-cationic polymerization type (
There are epoxy and vinyl ether based) oligomers.

[0013] The composition also includes an appropriate amount of photosensitizer and the viscosity is adjusted with a solvent. The coating method may be any of printing methods such as spinner, roll coater, and offset printing. In order to fill the gap with the color filter and improve flatness, the UV irradiation conditions (peak, cumulative irradiation amount,
Film thickness uniformity can be improved by adjusting the photoinitiator type, amount, and pre-bake conditions (lamp source height, etc.).

[0014]

[Examples] Hereinafter, the present invention will be explained in detail using examples. Figure 1
2 shows the manufacturing process of the color filter used in the color display device of the present invention. (2) An ITO film 2 is formed on the insulating substrate 1 by sputtering or the like, and etched into any pattern that can be electrodeposited. (FIG. 1(a)) ■ Color filters 3 of the three primary colors of red, green, and blue are formed with a thickness of 1.5 μm on the ITO film by electrodeposition. (Figure 1(b)) (Electrodeposition solution: Shinto Chemitron) ■ Photoinitiator Irgacure 184 (Ciba Geigy) was added to the photosensitive resin (Aronix M5515, Toagosei Chemical Industry) at 0.2 PHR.
After applying the formulated clear liquid with a solid content of 15% (by weight) using a spinner at 1000 rpm for 15 seconds, prebaking was performed at 70° C. for 10 minutes, and the film formed was 2.0 μm thick. (Fig. 1(c)) ■ Irradiation from the back of the coated surface with a high-pressure mercury UV lamp (80 W/cm manufactured by Ushio Inc.) (0.
3WS/cm2). (FIG. 1(d)) ■ The uncured portion of the coating was eluted by immersion in a developer (manufactured by Shinto Chemitron) for 2 minutes.

[0015] Next, after thoroughly washing with isopropyl alcohol and drying, it was fired at 200°C for 60 minutes. (Figure 1(e)
)) ■ ITO film 5 was formed by sputtering method. The film thickness was 800 Å, and the sheet resistance was 35 Ω/□. (Fig. 1(f)) ■Furthermore, by sputtering method, Cr
A metal film 6 was formed (FIG. 1(g)), and a lattice pattern was formed by photofabrication. (Figure 1 (
h) (i) (j)) The color filter manufactured in this way was manufactured as a color display device shown in FIG. 5 together with a TFT substrate on which TFT elements were formed on the counter substrate.

The black matrix 52 formed in the color display device of the present invention has a light shielding rate of 99.99%, which is TF
A high quality result was obtained with no light leakage of T.

[0017]

As explained in the Examples, by employing the method of the present invention, a color display device with good quality was obtained that did not cause failure of TFT elements due to light leakage. Furthermore, by using inexpensive equipment with good productivity, it is possible to supply inexpensive products.

More specifically, since the transparent conductive film and the metal film are laminated, even if the resistance value of the transparent conductive film itself is high, the metal film has the effect of lowering the resistance of the transparent conductive film as a result. Motsu. This allows the thickness of the transparent conductive film to be reduced, thereby improving the transmittance of the transparent conductive film and shortening the film forming time. The former can lead to improved quality of color display devices, and the latter can contribute to cost reduction.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a manufacturing process of a color filter including a black matrix according to the present invention.

FIG. 2 is a longitudinal cross-sectional view of a color filter substrate using a conventionally known metal film as a black matrix.

FIG. 3 is a longitudinal cross-sectional view of a color filter substrate using a conventionally known black photosensitive resin as a black matrix.

FIG. 4 is a longitudinal cross-sectional view of a substrate in which a black matrix is formed by overlapping color filters, which is conventionally known.

FIG. 5 is a schematic cross-sectional view of a color filter substrate manufactured by the method for manufacturing a multicolor display device according to the present invention.

[Explanation of symbols]

1, 21, 31, 41, 45, 51, 55 Glass substrate 2R, 3R, 4R, 5R Red filter 2G, 3
G, 4G, 5G Green filter 2B, 3B, 4B,
5B Blue filter 22, 32, 42, 52 Black matrix 23, 33, 43, 53 Protective film 5, 24, 34, 44, 54, 57 Transparent conductive film 56
TFT elements 58, 59 Polarizer 50 Liquid crystal 60 Organic film

Claims (1)

[Claims] 1. A color display device in which a transparent glass substrate and a color filter substrate having a colored portion and a light-shielding thin film face each other with an optically active material interposed therebetween, wherein the color filter substrate is manufactured by the following manufacturing process. A method for manufacturing a color display device. (a) Step of forming a color filter on a glass substrate (
b) Forming an organic film between color filters using a photosensitive resin by back exposure method (c) Forming a transparent conductive thin film on the color filter substrate (d) Forming a metal film on the transparent conductive thin film Step (e) of forming
Process of forming a pattern on a metal film by photofabrication