JPH07128512A - Color filter and its production - Google Patents

Abstract

PURPOSE:To provide the color filter having small light reflection from light shielding parts and good smoothness. CONSTITUTION:This color filter has transparent colored layers which are disposed in a pattern form in pixel parts and color the transmitted light of these pixel parts by each of respective colors and the light shielding parts which are disposed in a pattern form in the spacing parts between the respective pixels (inter-pixel parts) and shut off the light transmission from these parts. A transparent resin layer 2 which is applied uniformly over the entire surface on a transparent substrate 1 and generates selective dyeability by an exposing treatment is exposed from the transparent colored layer 3R, 3G, 3B side formed in the pixel parts thereon and these exposed parts are dyed black, by which the light shielding parts 2a are formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent colored layer which is provided in a pattern at a pixel portion on a transparent substrate and colors transmitted light of this pixel portion for each color, and a gap between each pixel on the transparent substrate. The present invention relates to a color filter including a light-shielding portion that is provided in a pattern in a portion (pixel portion) and that blocks transmitted light from this portion, and a method for manufacturing the color filter. The present invention relates to a filter and a manufacturing method thereof.

[0002]

2. Description of the Related Art In a liquid crystal display device, a liquid crystal material is sealed between a front substrate and a rear substrate, and a voltage is applied to a transparent electrode provided on each of the front substrate and the rear substrate to drive the liquid crystal substance. It is a display device that displays a screen by controlling transmission / non-transmission of light rays. When color display is performed by this liquid crystal display device, a color filter for coloring the transmitted light in each color is applied as the front substrate or the rear substrate.

A color filter of this kind generally has a structure as shown in FIG. That is, reference numeral 10 in FIG. 2 denotes a transparent substrate such as a glass substrate, and a transparent colored layer 12 is provided in a pattern on pixel portions on the transparent substrate 10. The transparent colored layer 12 is for coloring the transmitted light transmitted through the pixel portion for each color, and is generally the three primary colors of light: red, green and blue (depending on the purpose, red, green and blue may be complementary colors). ) Three colored transparent layers 12R, 12G, and 12B are provided for each pixel.

Further, since the transmitted light from the gap between pixels (inter-pixel portion) becomes ambient light and reduces the contrast of the screen, a light-shielding portion 11 for blocking ambient light is provided in the inter-pixel portion. Has been. Then, the transparent colored layer 1
In order to ensure the positional accuracy of 2R, 12G, 12B and the light shielding portion 11, the transparent colored layers 12R, 12G, 12B are formed wider than the pixels.
In the boundary portion between the G and 12B and the light shielding portion 11, both are configured to overlap each other.

When the color filter is applied to the front substrate or the rear substrate of the liquid crystal display device, the gap between the front substrate and the rear substrate is made uniform over the front surface to stabilize the driving of the liquid crystal substance. Therefore, the transparent resin layer 13 is provided on the entire surface to smooth the surface.

[0006]

By the way, in this type of color filter, a thin film made of vacuum-deposited metal chromium or a resin in which a black pigment is dispersed is used as the light-shielding portion 11. Among these, the metal chrome thin film is excellent as the light-shielding portion in that it has excellent light-shielding properties, but since it is formed by the vacuum deposition method, the manufacturing cost is high and the light reflectance is as high as 50 to 60%. Therefore, there is a problem that the display screen produces reflected light and warps to lower the contrast. Although a thin film having a two-layer structure of chromium oxide / metal chromium has been developed to reduce the reflectance, the reflectance is reduced to 10% even if the manufacturing process is increased and the chromium oxide thin film is added. It was nothing more than

On the other hand, the resin in which the black pigment is dispersed is excellent in that the manufacturing cost is low and the light reflection is small, but in order to improve the light shielding property, the film thickness is set to 1.2 μm or more. There was a need. Therefore, at the boundary portion where the light-shielding portion 11 and the transparent colored layers 12R, 12G, and 12B overlap, the total film thickness becomes large to form a protrusion, and the surface of the transparent resin layer 13 provided thereon also has the protrusion. Based on this, the convex portion 14 is formed. In addition, the height of the convex portion 14 may reach about 0.8 μm, and as a result, the gap between the front substrate and the rear substrate becomes non-uniform, and the liquid crystal material cannot be stably driven. Was.

The present invention has been made in view of the above conventional problems, and an object of the present invention is to provide a color filter having a small light reflection from a light shielding portion and a good smoothness, and a manufacturing method thereof. Especially.

[0009]

In order to solve the above problems, a color filter of the present invention is a transparent colored layer which is provided in a pattern on a pixel portion on a transparent substrate and colors transmitted light of the pixel portion for each color. And a light-shielding portion that is provided in a pattern in a gap portion (inter-pixel portion) between pixels on the transparent substrate and blocks light transmission from this portion, wherein the light-shielding portion is the transparent substrate. Formed by exposing the transparent resin layer, which is selectively dyeable by uniformly exposing the entire surface of the upper surface, from the side of the transparent colored layer formed on the transparent resin layer, and dyeing this exposed portion black. It is characterized by being.

Further, the method for manufacturing a color filter of the present invention comprises a transparent colored layer which is provided in a pattern on a pixel portion on a transparent substrate and colors transmitted light of the pixel portion for each color.
A method of manufacturing a color filter, comprising: a light-shielding portion that is provided in a pattern in a gap portion (inter-pixel portion) between pixels on the transparent substrate and blocks light transmission from this portion,
After uniformly coating a transparent resin layer which causes selective dyeability by an exposure process on the entire surface of the transparent substrate, and then forming a transparent colored layer in a pattern on pixel portions on the transparent resin layer,
The transparent resin layer is exposed from the transparent colored layer side, and the exposed portion is dyed black to form the light shielding portion.

[0011]

According to the present invention, the transparent resin layer uniformly coated on the entire surface of the transparent substrate is exposed from the transparent colored layer side formed on the pixel portion thereon, and the exposed portion is blackened. A light shielding part is formed by dyeing. That is, a pattern of a smooth light-shielding portion is formed on a transparent substrate, and a transparent colored layer is formed in the opening (pixel portion). Therefore, the light reflection from the light-shielding portion can be significantly reduced as compared with the conventional color filter in which the light-shielding portion is made of a chrome thin film, and since there is no step between the light-shielding portion and the pixel portion, the pixel portion is transparent. Even if the colored layer is formed, the surface has high smoothness, and as a result, a high quality color filter can be obtained.

Further, according to the present invention, since the process allowable width in manufacturing is extremely wide and the positional accuracy of the transparent colored layer and the light shielding portion can be sufficiently secured, a color filter which is simple and inexpensive to manufacture can be obtained.

[0013]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a sectional view showing a manufacturing process of a color filter according to an embodiment of the present invention.

Reference numeral 1 denotes a transparent substrate such as a glass substrate. First, as shown in FIG. 1 (a), a transparent resin material which is selectively dyeable by an exposure process is spin-coated or formed on the entire surface of the transparent substrate 1. It is evenly applied by the roll coating method and is 200
The transparent resin layer 2 having a flat surface with a thickness of about 2 μm is formed by drying at 0 ° C. for about 1 hour. As such a transparent resin material, a quinonediazide-based photosensitive resin that produces a -COOH group by an ultraviolet exposure treatment or an organic polysilane-based resin that produces a -SiOH group by the above exposure can be applied.
In either case, the exposed area can be selectively dyed with a cationic dye.

Next, as shown in FIG. 1 (b), the transparent colored layer 3 is precisely formed on the transparent resin layer 2 thus formed at a portion corresponding to a pixel portion, specifically, three colored transparent colored layers. Three
R, 3G and 3B are formed. This three-color transparent colored layer 3
R, 3G, and 3B can be formed by, for example, applying a photosensitive resin on the entire surface, exposing and developing the pixel pattern in a pixel pattern, and then dyeing the remaining photosensitive resin in a pixel pattern with an acid dye ( Dyeing method). The photosensitive resin may be made of any material that is not dyed with a cationic dye. For example, gelatin, low molecular weight gelatin, glue, casein, polyvinyl alcohol, and synthetic polyacrylamide resin can be used.

Further, a printing ink in which a color pigment is dispersed is printed in a pattern on the pixel portion (printing method), or a photosensitive resin in which the color pigment is dispersed is applied on the entire surface and exposed to expose a pixel pattern. It can also be formed by developing into a shape (pigment dispersion method). An acrylic photosensitive resin containing methyl methacrylate as a main component can be applied as such a photosensitive resin.

Next, as shown in FIG. 1C, UV light is applied from above the transparent colored layer 3 to, for example, 50 to 200 mJ / cm.
Irradiate the entire surface with an exposure amount of ² . At this time, only the transparent resin layer 2 in the inter-pixel portions exposed by the transparent colored layers 3R, 3G, and 3B serving as a mask is exposed to cause dyeability.

After the above exposure, it is immersed in a black cationic dye solution heated to 60 to 80 ° C. for about 10 minutes to form a light shielding portion 2a in which the exposed portion is dyed black (FIG. 1 (d)). reference). As such a black cationic dye, for example, DiacrylBlack BSL-F
And Diacryl Black RTL-PF (both manufactured by Mitsubishi Kasei Co., Ltd.) can be applied.

Even if a portion of UV light is transmitted through the transparent colored layers 3R, 3G, 3B by making the above UV light irradiation amount a little over, the transparent colored layers 3R, 3G, 3B are in contrast to the black cationic dye. Since it is non-staining, even if there is side dyeing (the transparent resin layer 2 in the part corresponding to the pixel part around the light shielding part 2a is dyed black), it is a slight amount that does not cause any inconvenience. In this respect, the tolerance of the manufacturing process is extremely wide.

Even if the above-mentioned dyeing conditions (mainly dyeing time) are slightly exceeded, the transparent resin layer 2 in the portion corresponding to the pixel portion other than the light shielding portion 2a does not receive UV light and is dyed. (As described above, even if UV light passes through the transparent colored layers 3R, 3G, and 3B to reach the lower transparent resin layer 2 due to overexposure of UV light as described above, the amount of UV light is extremely small and dyeability is low. Side dyeing is unlikely to occur, and the tolerance of the manufacturing process is extremely wide in this respect as well.

An unillustrated overcoat layer and transparent conductive film layer can be formed on the entire surface including the transparent colored layer 3 and the light shielding portion 2a thus formed. As the overcoat layer, a thermosetting acrylic resin or the like can be used.

The transparent conductive film layer can be formed, for example, by forming a transparent conductive film of ITO made of indium oxide (93% by weight) and tin oxide (7% by weight) by vacuum vapor deposition or the like. it can.

In this way, the color filter is completed.

[0025]

As described in detail above, according to the present invention, a transparent colored layer having a transparent resin layer uniformly applied on the entire surface of a transparent substrate is formed in a pixel portion thereon. Since the exposed portion is exposed from the side and the exposed portion is dyed black to form the light-shielding portion, there is no step between the light-shielding portion and the pixel portion, and the surface is smooth.
Moreover, it is possible to form a light-shielding portion having low reflection and high light-shielding density. Therefore, even if the transparent colored layer is formed on the pixel portion, the surface has high smoothness, and as a result, a high quality color filter can be provided.

Further, according to the present invention, since the tolerance of the manufacturing process is extremely wide and the positional accuracy between the transparent colored layer and the light shielding portion can be sufficiently secured, it is possible to provide a color filter which is simple and inexpensive to manufacture. it can.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a manufacturing process of a color filter according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a structure of a conventional color filter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transparent substrate 2 Transparent resin layer 2a Light-shielding part 3 Transparent colored layer 10 Transparent substrate 11 Light-shielding part 12 Transparent colored layer 13 Transparent resin layer 14 Convex part

Claims (2)

[Claims] 1. A transparent colored layer provided in a pattern on a pixel portion on a transparent substrate for coloring transmitted light of the pixel portion for each color, and a gap portion (inter-pixel portion) between each pixel on the transparent substrate. In a color filter having a light-shielding portion that is provided in a pattern on the transparent substrate and blocks light transmission from this portion, the light-shielding portion is selectively dyeable by an exposure treatment uniformly applied to the entire surface of the transparent substrate. A color filter formed by exposing a transparent resin layer that causes the above from the side of the transparent colored layer formed on the transparent resin layer, and dyeing the exposed portion in black. 2. A transparent coloring layer which is provided in a pattern on a pixel portion on a transparent substrate and which colors transmitted light of this pixel portion for each color, and a gap (inter-pixel portion) between each pixel on the transparent substrate. In a method for producing a color filter, which is provided in a pattern on a light-shielding portion that blocks light transmission from this portion, a transparent resin layer that causes selective dyeability by exposure treatment is uniformly formed on the entire surface of the transparent substrate. After coating, and then forming a transparent colored layer in a pattern on the pixel portion on the transparent resin layer, the transparent resin layer is exposed from the transparent colored layer side, and the exposed portion is dyed black to shield the light. A method for producing a color filter, which comprises forming a portion.