JPH0772321A - Color filter and its production - Google Patents

Abstract

PURPOSE:To provide the color filter which is small in light reflection from light shielding parts and has good smoothness. CONSTITUTION:This color filter has transparent colored layers 6R, 6G, 6B which are disposed in pattern forms in the pixel parts on a transparent substrate 1 and color the transmitted light of the pixel parts by each of respective colors and the light shielding parts which are disposed in pattern form in the spacing parts between the respective pixels (between the pixels) on the transparent substrate 1 and shield the light transmission from these parts. The light shielding parts described above are formed by laminating dyed resin layers 2B dyed with black dyes and pigment dispersed resin layers 3P dispersed with black pigments. The parts corresponding to the pixel parts are transparent resin layers 2P formed by decoloring the black dyes of the black dyed resin layers of the lower layer simultaneously with alkaline development at the time of forming the black pigment dispersed resin layers 3P by a photolithography method.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent coloring 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 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 color 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, in FIG. 2, reference numeral 10 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). ) The three colored transparent colored 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 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 has been developed as a two-layer structure of chromium oxide / metal chromium in order to reduce the reflectance, the reflectance can be reduced by 10% even if the manufacturing process is increased and a chromium oxide thin film is added. It didn't pass.

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 has a black lower layer. A dyed resin layer dyed with a dye, an upper layer is a laminate of a pigment-dispersed resin layer in which a black pigment is dispersed, and a portion corresponding to a pixel portion of the lower black dyed resin layer is a black layer of the upper layer. It is characterized in that it is a transparent resin layer in which the black dye is decolorized at the same time as alkali development when forming the pigment-dispersed resin layer by the photolithography method.

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,
A dyed resin layer dyed with a black dye is uniformly formed on the transparent substrate, and a photosensitive resin in which a black pigment is dispersed is applied thereon to uniformly form a black pigment-dispersed resin layer. , And then selectively exposing this black pigment-dispersed resin layer,
By patterning the black pigment-dispersed resin layer by alkali development, at the same time, the black dye in the portion corresponding to the pixel portion of the lower black dyed resin layer was decolorized to form the light-shielding portion as a transparent resin layer. After that, a transparent colored layer is formed in a pattern at a portion corresponding to the pixel portion.

[0011]

According to the present invention, the light-shielding portion has a laminated structure of the lower black dye resin layer and the upper black pigment-dispersed resin layer, and the pixel portion has the black color uniformly formed on the transparent substrate. Since the portion corresponding to the pixel portion of the dyeing resin layer is a transparent resin layer that is decolorized by alkali development when patterning the upper black pigment-dispersed resin layer, the light-shielding effect of the light-shielding portion is the black dyeing resin layer. And the black pigment-dispersed resin layer, the level difference between the pixel portion and the light-shielding portion is equal to the thickness of the black pigment-dispersed resin layer. Therefore, a light-shielding portion having low reflection, high light-shielding density and a relatively small step with the pixel portion is formed, and even if a transparent colored layer is formed on the light-shielding portion, the surface has high smoothness, resulting in low cost. A high quality color filter can be obtained.

[0012]

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 is a transparent substrate such as a glass substrate. First, a black dyed resin layer 2 is uniformly formed on the transparent substrate 1 (see FIG. 1A). The black dyed resin layer 2 can be formed by applying a transparent resin in which a black dye is dispersed on the transparent substrate 1. Alternatively, a transparent and easily dyeable dyeable resin layer (thickness: about 1.0 μm) of acrylic resin, gelatin, PVA or the like is formed on the transparent substrate 1, and the dyeable resin layer is used as a black dye. It can be formed by dyeing.

As the black dye for dyeing the dyeable resin layer, for example, Diacid Milling Blac
Using GL (manufactured by Mitsubishi Kasei Co., Ltd.), a 1% solution containing 1% acetic acid is dyed, for example, at 70 ° C. for 3 minutes.

Then, a photosensitive resin having a black pigment dispersed therein is applied to the surface of the black dyed resin layer 2 to uniformly form a black pigment dispersed resin layer (thickness: about 0.5 μm) 3 (FIG. 1).
(See (b)).

As the photosensitive resin to be used, a negative type is used in this embodiment, but a positive type may be used.

Next, the portion corresponding to the inter-pixel portion of the black pigment dispersion resin layer 3 is selectively exposed 5 through the photomask 4 (see FIG. 1 (c)) and alkali-developed to obtain a black color. The pigment-dispersed resin layer 3 is patterned to form the patterned black pigment-dispersed resin layer 3P (see FIG. 1D).

By this alkali development, the black dye-dispersed resin layer 3 is developed, and at the same time, the black dye in the portion corresponding to the pixel portion of the lower black dyed resin layer 2 is decolorized during the development to form the transparent resin layer 2P. (See FIG. 1D). The black dye in the portion 2B corresponding to the inter-pixel portion of the black dye resin layer 2 is not decolorized by using the patterned black pigment dispersion resin layer 3P as a mask.

As the developing solution, an alkaline type is selected, for example, 65 g of caustic soda and 50 g of sodium carbonate.
And a developer having a composition of 10 liters of water can be used.

In this way, a light-shielding portion having a laminated structure of the black dye resin layer 2B and the black pigment dispersion resin layer 3P is formed in the portion corresponding to the inter-pixel portion on the transparent substrate 1, and the portion corresponding to the pixel portion is the black dye resin. The transparent resin layer 2P is formed by decoloring the layer 2 and is opened.

After the above development, heat treatment is carried out at about 200 ° C. for 1 hour in order to have sufficient chemical resistance.

Next, as shown in FIG. 1 (e), a transparent colored layer 6, specifically three colored transparent colored layers 6R, 6G, and 6B, is formed at a portion corresponding to the pixel portion. The three-color transparent colored layers 6R, 6G, and 6B are formed, for example, by coating a photosensitive resin on the entire surface, exposing and developing in a pixel pattern shape, and then dyeing the remaining photosensitive resin in a pixel pattern shape with a dye. Can be formed (staining method). It is also possible to form a pattern by printing a printing ink in which a color pigment is dispersed on the pixel portion (printing method). Alternatively, a photosensitive resin in which a color pigment is dispersed may be applied on the entire surface, exposed, and developed into a pixel pattern (pigment dispersion method).

Further, an overcoat layer and a transparent conductive film layer (not shown) are further formed thereon.

A thermosetting acrylic resin or the like can be used as the overcoat layer.

As the transparent conductive film layer, indium oxide and tin oxide are vacuum-deposited and, if necessary, patterned by photoetching to form a transparent conductive film layer of ITO.

In this way, the color filter is completed.

[0028]

As described above in detail, according to the present invention, the portion corresponding to the inter-pixel portion on the transparent substrate has a light-shielding portion having a laminated structure of a black dye resin layer and a black pigment dispersion resin layer. Since the transparent resin layer is formed by decolorizing the black dyed resin layer, the portion corresponding to the pixel portion is formed.
The light-shielding portion exhibits the light-shielding effect by the two layers of the black dyed resin layer and the black pigment-dispersed resin layer, while the level difference between the pixel portion and the light-shielded portion is equal to the thickness of the black pigment-dispersed resin layer. Thus, it is possible to form a light-shielding portion having a relatively small step with the pixel portion, 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 can be manufactured at low cost, and as a result, a high quality color filter can be provided.

[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]

 1 Transparent Substrate 2 Black Dyeing Resin Layer 3 Black Pigment Dispersion Resin Layer 4 Photomask 5 Exposure 6 Transparent Coloring Layer 10 Transparent Substrate 11 Light-shielding Part 12 Transparent Coloring 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 comprising a light-shielding portion that is provided in a pattern in a pattern for blocking light transmission from this portion, the light-shielding portion has a lower layer dyed with a black dye resin layer,
The upper layer is a lamination of a pigment dispersion resin layer in which a black pigment is dispersed, and the portion corresponding to the pixel portion of the lower layer of the black dyed resin layer is subjected to the photolithography method using the upper layer of the black pigment dispersion resin layer. A color filter characterized by being a transparent resin layer in which a black dye is decolored at the same time as alkali development when forming. 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 of manufacturing a color filter comprising a light-shielding portion that is provided in a pattern and blocks light transmission from this portion, a dyeing resin layer dyed with a black dye is uniformly formed on the transparent substrate, and A black pigment-dispersed resin layer is uniformly formed by applying a photosensitive resin having a black pigment dispersed thereon, and then the black pigment-dispersed resin layer is selectively exposed and then alkali-developed. After patterning the black pigment-dispersed resin layer and at the same time forming the light-shielding portion as a transparent resin layer by decolorizing the black dye in the portion corresponding to the pixel portion of the lower black dyed resin layer,
A method of manufacturing a color filter, comprising forming a transparent colored layer in a pattern on a portion corresponding to the pixel portion.