JPH06175118A - Production of black matrix substrate - Google Patents

Abstract

PURPOSE:To provide the black matrix substrate having high dimensional accuracy and excellent light shieldability at a low cost by heat treating a transparent substrate, fixing metals to a relief to form the catalyst-contg. relief and forming the black relief. CONSTITUTION:A photosensitive resist contg. a hydrophilic resin is applied on the transparent substrate 13 to form a photosensitive resist layer 3. This photosensitive resist layer 3 is then exposed via a photomask 9 for the black matrix (black relief). The photosensitive resist layer 3 after the exposing is developed to form the relief 4 having patterns for the black matrix. After the transparent substrate 13 is heat treated, the metals to serve as the catalyst for electroless plating are fixed to the relief 4 to form the catalyst-contg. relief 5. The catalyst-contg. relief 5 on the transparent substrate 13 is brought into contact with an electroless plating liquid, by which the black relief is formed. The black matrix 14 is thus formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a black matrix substrate, and more particularly to a method of manufacturing a black matrix substrate which can easily form a black matrix having high dimensional accuracy and excellent light shielding property.

[0002]

2. Description of the Related Art In recent years, monochrome or color liquid crystal displays have been attracting attention as flat displays. The liquid crystal display includes an active matrix system and a simple matrix system for controlling the three primary colors, and a color filter is used in each system. In the liquid crystal display, the constituent pixel portions have three primary colors (R, G, B), and the electrical switching of the liquid crystal controls the transmission of each light of the three primary colors to perform color display.

This color filter is formed by forming each colored layer, a protective layer and a transparent electrode layer on a transparent substrate. Then, in order to improve the coloring effect and the display contrast, a pattern (black matrix) having a light-shielding property is formed at the boundary portion of each pixel of R, G and B of the colored layer. Further, in an active matrix type liquid crystal display, since a thin film transistor (TFT) is used as a switching element, it is necessary to suppress light leak current. Therefore, the black matrix is required to have a high light-shielding property.

Conventionally, as a black matrix, a vapor-deposited chrome thin film is photo-etched to form a relief, a hydrophilic resin relief is dyed, a relief formed using a photosensitive solution in which a black pigment is dispersed, and a black electrodeposition. Some were formed by electrodeposition of paint, some were formed by printing, and the like.

However, although the above vapor-deposited chrome thin film is photo-etched to form a relief, the dimensional accuracy is high, but a vacuum film-forming process such as vapor deposition or sputtering is required and the manufacturing process is complicated. High manufacturing cost,
Further, in order to increase the display contrast under strong external light, it is necessary to suppress the reflectance of chromium, and thus it is necessary to perform sputtering of low-reflection chromium, which is more costly to manufacture. Further, the method using a photosensitive resist in which the above black dye or pigment is dispersed, the manufacturing cost is low, but it is difficult to obtain sufficient light-shielding property because the photoprocess is likely to be insufficient because the photosensitive resist is black. However, there is a problem that a high quality black matrix cannot be obtained. Further, although the black matrix formation by the above-mentioned printing method can reduce the manufacturing cost,
There was a problem that the dimensional accuracy was low.

[0006]

In order to solve the above problems, a photosensitive resist layer containing a hydrophilic resin is formed on a transparent substrate, and the above-mentioned method is performed through a photomask having a black matrix pattern. The photosensitive resist layer is exposed and developed to form a relief, and a metal compound serving as a catalyst for electroless plating is added to the relief to form a catalyst-containing relief. The black matrix is formed by precipitating the metal particles by contacting with the black matrix. The manufacturing method of the black matrix substrate using such electroless plating is not complicated in the manufacturing process,
Moreover, the dimensional accuracy of the black matrix is high and the light-shielding property is excellent. However, in the formation of the black matrix substrate according to the above electroless plating method, metal particles do not precipitate unless an electroless plating solution containing a strong reducing agent such as a boron-based reducing agent is used during electroless plating. There was a problem.

The present invention has been made in view of the above circumstances, and has high dimensional accuracy and light shielding that can be used for a flat display such as a liquid crystal display, an imager such as a CCD, or a color filter such as a color sensor. An object of the present invention is to provide a manufacturing method capable of manufacturing a black matrix substrate having excellent properties at low cost.

[0008]

In order to achieve such an object, the present invention provides a photosensitive resist layer containing a hydrophilic resin formed on a transparent substrate through a photomask having a black matrix pattern. Exposure and development to form a relief on the transparent substrate, a second step of heat-treating the transparent substrate, a metal containing a catalyst for electroless plating is fixed to the relief, and a relief containing catalyst is formed. And a fourth step of forming a black relief having a pattern for a black matrix by bringing the catalyst-containing relief into contact with an electroless plating solution.
In the third step, an aqueous solution of a reducing agent is applied to the relief and washed with water, and then an aqueous solution of a metal compound serving as a catalyst for electroless plating is applied to the relief to form the metal. An activation treatment for reducing the metal of the compound and fixing it to the relief, or a mixed aqueous solution of a metal compound serving as a catalyst for electroless plating and a reducing agent are applied to the relief and washed with water, and then an accelerator solution is applied to the relief. An accelerator treatment for reducing the metal of the metal compound and fixing it to the relief was adopted.

[0009]

[Function] The relief for the black matrix formed on the transparent substrate is heat-treated and then electroless plated to deposit a metal to form a black relief. Since the metal that serves as a catalyst for electroless plating is fixed in the relief of by electrolysis or accelerator treatment, even in electroless plating, electroless plating solution containing a weak reducing agent such as a phosphorus-based reducing agent for nickel can be used. Good metal deposition is possible, and it is not necessary to use an electroless plating solution containing a strong reducing agent such as a boron-based reducing agent, and the formed black matrix substrate has a high optical density and a low dimensional accuracy with low reflectance. Since it is good and a vacuum process or the like is not necessary, the manufacturing cost can be reduced.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an example of an active matrix type liquid crystal display (LCD) using a black matrix substrate manufactured according to the present invention, and FIG. 2 is a schematic sectional view of the same. 1 and 2, the LCD 1 has a color filter 10 and a transparent glass substrate 20 which are opposed to each other with a sealing material 30 in between, and a thickness of about 5 to 1 made of twisted nematic (TN) liquid crystal between them.
A liquid crystal layer 40 having a thickness of about 0 μm is formed, and polarizing plates 50 and 5 are provided outside the color filter 10 and the transparent glass substrate 20.
1 is provided and configured.

FIG. 3 is an enlarged partial sectional view of the color filter 10. In FIG. 3, the color filter 10 comprises a black relief (black matrix) 14 on a transparent substrate 13.
Forming a black matrix substrate 12 and a black matrix 14 of the black matrix substrate 12.
The colored layer 16 formed between them, and the protective layer 18 provided so as to cover the black matrix 14 and the colored layer 16.
And a transparent electrode 19. The color filter 10 is arranged such that the transparent electrode 19 is located on the liquid crystal layer 40 side. The colored layer 16 is the red pattern 16
It is composed of R, green pattern 16G, and blue pattern 16B, and the array of each colored pattern is a mosaic array as shown in FIG. The arrangement of the coloring pattern is not limited to this, and may be a triangular arrangement, a stripe arrangement, or the like.

Display electrodes 22 are provided on the transparent glass substrate 20 so as to correspond to the respective colored patterns 16R, 16G and 16B, and each display electrode 22 has a thin film transistor (TFT) 24. Further, a scanning line (gate electrode busbar) 26a and a data line 26b are arranged between the respective display electrodes 22 so as to correspond to the black matrix 14.

In the LCD 1 as described above, each of the colored patterns 16R, 16G and 16B constitutes a pixel, and the display electrode corresponding to each pixel is turned on and off while the illumination light is emitted from the polarizing plate 51 side. The layer 40 operates as a shutter, and light is transmitted through each pixel of the colored patterns 16R, 16G, and 16B to perform color display.

The transparent substrate 13 of the black matrix substrate 12 constituting the color filter 10 is a rigid material such as quartz glass, low expansion glass or soda lime glass, a transparent resin film, an optical resin plate or the like. It is possible to use a flexible material having such flexibility. Among them, Corning 7059 glass is a material with a small coefficient of thermal expansion, has excellent dimensional stability and workability in high-temperature heat treatment, and is a non-alkali glass that does not contain an alkali component in the glass. It is suitable for a matrix type LCD color filter.

An example of manufacturing the black matrix substrate 12 according to the present invention will be described with reference to FIG. First, a photosensitive resist containing a hydrophilic resin is applied on the transparent substrate 13 to form a photosensitive resist layer 3 having a thickness of about 0.1 to 5.0 μm (FIG. 4 (A)). Next, the photosensitive resist layer 3 is exposed through the black matrix photomask 9 (FIG. 4B). Then, the exposed photosensitive resist layer 3 is developed to form a relief 4 having a pattern for a black matrix (FIG. 4C).
Next, the transparent substrate 13 is heat-treated (100 to 200 ° C.,
After 5 to 30 minutes), a metal serving as a catalyst for electroless plating is fixed to the relief 4 to obtain a catalyst-containing relief 5 (FIG. 4 (D)). Then, the catalyst-containing relief 5 on the transparent substrate 13 is brought into contact with an electroless plating solution to form a black relief, thereby forming a black matrix 14 (FIG. 4 (E)).

Examples of the photosensitive resist used in the present invention include natural proteins such as gelatin, casein, glue and ovalbumin, carboxymethyl cellulose, polyvinyl alcohol, polyacrylic acid, polyacrylamide, polyvinylpyrrolidone, polyethylene oxide and maleic anhydride. For example, a reaction product of a diazonium compound having a diazo group and paraformaldehyde with respect to a polymer and a hydrophilic resin such as a carboxylic acid-modified product or a sulfonic acid-modified product of the above resin, or a mixture of two or more of them. Diazo resin, an azide compound having an azido group, a cinnamic acid condensation resin obtained by condensing polycinnyl alcohol with cinnamic acid, a resin using a stilbazolium salt, a photocurable photosensitive group such as ammonium dichromate Also has It may be mentioned those obtained by imparting photosensitivity by adding. Needless to say, the photosensitive group is not limited to the above photocurable photosensitive group.

As described above, the hydrophilic resin is contained in the photosensitive resist, so that when the catalyst-containing relief 5 comes into contact with the electroless plating solution as described above, the electroless plating solution contains the catalyst-containing relief 5. The metal particles are easily deposited in the catalyst-containing relief 5 uniformly. Therefore, the formed black matrix 14 has sufficient blackness and low reflectance, and the problem of reflection by the metal layer in the conventional chromium thin film formation can be solved.

As the metal compound used as a catalyst for electroless plating used in the present invention, for example, chlorides such as palladium, gold, silver, platinum and copper, water-soluble salts such as nitrates, and complex compounds are used, and they are commercially available as an aqueous solution. The existing activator solution for electroless plating can be used as it is.

The formation of the catalyst-containing relief 5 using the metal compound which serves as a catalyst for the above electroless plating in the present invention is performed by the following activation treatment or accelerator treatment.

To form the catalyst-containing relief 5 by the activation treatment, first, the transparent substrate after the heat treatment is immersed in an aqueous solution of a reducing agent and washed with water, and then the relief 4 is further treated with a metal compound serving as a catalyst for electroless plating as described above. It is performed by immersing it in the aqueous solution. As a result, the metal of the metal compound (for example, palladium when palladium chloride is used as the metal compound serving as a catalyst for electroless plating) is reduced to form a nucleus and adhere to the relief 4. Then, the catalyst-containing relief 5 is formed by washing with water and drying.

On the other hand, in forming the catalyst-containing relief 5 by the accelerator treatment, the transparent substrate is immersed in a mixed aqueous solution of a metal compound serving as a catalyst for electroless plating and washed with water, and then further immersed in an accelerator solution. This allows
Similar to the activation treatment described above, the metal of the metal compound is reduced to form nuclei and adhere to the relief 4. Then, the catalyst-containing relief 5 is formed by washing with water and drying.

Examples of the reducing agent used in the activation treatment or accelerator treatment include tin chloride, hydrazines, hydroquinones, hydrosulfides, borane derivatives and borazane derivatives.

The accelerator solution used for the accelerator treatment is an aqueous sulfuric acid solution (concentration: 50-100).
g / l), hydrochloric acid aqueous solution (concentration: 50 to 100 g / l), tetrafluoroboric acid aqueous solution (concentration: 50 to 100 g / l), sodium borohydride and the like.

The content of the metal serving as the catalyst for electroless plating contained in the catalyst-containing relief 5 formed by the activation treatment or accelerator treatment as described above is about 0.0001 to 0.001% by weight. preferable.

The electroless plating solution is, for example, a reducing agent such as hypophosphorous acid, sodium hypophosphite, sodium borohydride, N-dimethylamineborane, a borazine derivative, hydrazine and formalin, and nickel, cobalt,
Water-soluble reducible heavy metal salts such as iron, copper, and chromium, basic compounds such as caustic soda and ammonium hydroxide that improve plating rate, reduction efficiency, etc., pH adjusting agents such as inorganic acids and organic acids, and quenching agents. Buffer agents represented by alkali salts of oxycarboxylic acids such as sodium acid and sodium acetate, boric acid, carbonic acid, organic acids and inorganic acids, complexing agents for the stability of heavy metal ions, and reaction accelerators An electroless plating solution containing a stabilizer, a surfactant, and the like is used.

In the present invention, as described above, a metal serving as a catalyst for electroless plating is fixed to the catalyst-containing relief 5, so that a weak reducing agent such as a phosphorus-based reducing agent can be used during electroless plating. Good metal deposition is possible even with the electroless plating solution containing it, and it is not necessary to use an electroless plating solution containing a strong reducing agent such as a boron-based reducing agent. Thus, the black matrix substrate 14 is formed.

Black matrix substrate 1 as described above
The formation of the colored layer 16 including the red pattern 16R, the green pattern 16G, and the blue pattern 16B between the two black matrices 14 can be performed by various known methods such as a dyeing method, a dispersion method, a printing method, and an electrodeposition method. it can.

A protective layer 18 provided so as to cover the black matrix 14 and the colored layer 16 of the color filter 10.
Is for smoothing the surface of the color filter 10, improving reliability,
Also, the purpose is to prevent contamination of the liquid crystal layer 40 and the like, and can be formed using a transparent resin such as an acrylic resin, an epoxy resin, a polyimide resin, or a transparent inorganic compound such as silicon dioxide. . The thickness of the protective layer is preferably about 0.5 to 50 μm.

As the transparent common electrode 19, for example, an indium tin oxide (ITO) film can be used. IT
The O film can be formed by a known method such as a vapor deposition method and a sputtering method, and the thickness is preferably about 200 to 2000 Å.

Next, the present invention will be described in more detail with reference to experimental examples. (Experimental example) 7059 glass (thickness = 1.1 mm) manufactured by Corning Inc. is used as a transparent substrate, and a photosensitive resist having the following composition is applied on the transparent substrate by a spin coating method (rotation speed = 1600 rpm, 3 seconds). And then 70 ° C, 10
The photosensitive resist layer (thickness = 0.6 μm) was formed by drying (pre-baking) under the condition of 1 minute.

(Composition of photosensitive resist) -Polyvinyl alcohol 4.47% by weight aqueous solution (Nippon Gosei Kagaku's Gohsenal T-330) ... 1000 parts by weight-Diazo resin 5% by weight aqueous solution (Shinko Giken D-011) ... 57 .1 part by weight Next, using a contact printer made by Dainippon Screen Co., Ltd. for the photosensitive resist layer, Vq = 60 seconds, 75
The pattern (line width = 45 μm) for the black matrix was exposed by counting (134.25 mJ / cm ² ). After that, development was performed using water at room temperature (rotation speed = 150 rpm, 4
After 5 seconds), it was air-dried to form a relief for the black matrix having a line width of 47 μm.

Next, this transparent substrate was subjected to heat treatment at 90 ° C. for 30 minutes, then immersed in a tin chloride aqueous solution (Pink Schumer made by Kanigen Japan Co., Ltd.) for 1 minute, and shower washed. Furthermore, after immersing the transparent substrate in an aqueous solution of palladium chloride (Nippon Kanigen's Red Sumer) for 1 minute,
Shower washing and drying were performed to obtain a relief containing a catalyst.

After that, the transparent substrate is immersed in a nickel plating solution containing a hypophosphite reducing agent at 30 ° C. (nickel plating solution Tsp55 nickel A / C = 1/2 manufactured by Okuno Seiyaku) for 4 minutes to deposit Ni particles. Then, it was washed with water and dried to obtain a black matrix substrate (Sample 1) having a black relief (black matrix).

Further, the relief was formed in the same manner as described above, and the transparent substrate after heat treatment at 90 ° C. for 30 minutes was mixed with an aqueous solution of tin chloride and an aqueous solution of palladium chloride (manufactured by Okuno Chemical Industries Co., Ltd.). 1 for TSP-catalyst
Immersion for 1 minute, shower cleaning is performed, and the transparent substrate is further immersed in an aqueous sulfuric acid solution (concentration: conc H ₂ SO ₄ 5 ml / l) for 1 minute, then shower cleaning and drying are performed to make the relief containing a catalyst. A black matrix substrate (Sample 2) was obtained in the same manner as Sample 1.

On the other hand, as a comparison, a transparent substrate that was heat-treated at 90 ° C. for 30 minutes in the same manner as in Sample 1 was used.
A black matrix substrate (Comparative Sample 1) was prepared in the same manner as Sample 1, except that an aqueous palladium chloride solution (Red Kumagen manufactured by Nihon Kanigen) was applied by a spin coating method (rotation speed = 100 rpm, 3 seconds) to obtain a catalyst-containing relief. ) Got.

The optical densities D and reflectances R of the black reliefs of the black matrix substrates (Samples 1 and 2 and Comparative Sample 1) produced as described above were measured. In Samples 1 and 2, D ≧ 3. 0, R ≦ 5%, and it was found that the black matrix for color filters had a sufficient optical density and low reflectance. However, in the comparative sample 1, precipitation of Ni in electroless plating was not seen.

[0037]

As described in detail above, according to the present invention, an electroless plating solution containing a weak reducing agent is used, and the reflectance is low, the dimensional accuracy is high, the optical density is high, and the adhesion to a transparent substrate is also high. It becomes possible to obtain a good black relief (black matrix), and a black matrix substrate provided with such a black relief (relief matrix) can constitute a color filter that is highly reliable and capable of high contrast. At the same time, since a vacuum process or the like is unnecessary, the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of an active matrix type liquid crystal display using a black matrix substrate manufactured according to the present invention.

FIG. 2 is a schematic sectional view of the liquid crystal display shown in FIG.

FIG. 3 is an enlarged partial sectional view of a color filter used in the liquid crystal display shown in FIG.

FIG. 4 is a process chart for explaining a method of manufacturing a black matrix substrate according to the present invention.

[Explanation of symbols]

 5 ... Catalyst-containing relief 9 ... Photomask for black matrix 10 ... Color filter 12 ... Black matrix substrate 13 ... Transparent substrate 14 ... Black matrix (black relief) 16 ... Coloring layer 16R, 16G, 16B ... Coloring pattern

Claims (1)

[Claims] 1. A photosensitive resist layer containing a hydrophilic resin formed on a transparent substrate is exposed and developed through a photomask having a pattern for a black matrix to form a relief on the transparent substrate. A second step of heat-treating the transparent substrate, a third step of fixing a metal serving as a catalyst for electroless plating to the relief to form a catalyst-containing relief, and an electroless plating solution for the catalyst-containing relief. And a fourth step of forming a black relief having a pattern for a black matrix by contacting the relief, and the third step, in which an aqueous solution of a reducing agent is applied to the relief and washed with water, and then the relief is further added. An activator for applying an aqueous solution of a metal compound, which serves as a catalyst for electroless plating, to reduce the metal of the metal compound and fix the metal to the relief. Solution or a mixed aqueous solution of a metal compound that serves as a catalyst for electroless plating and a reducing agent is applied to the relief and washed with water, and then an accelerator solution is applied to the relief to reduce the metal of the metal compound to reduce the relief. A method of manufacturing a black matrix substrate, characterized by comprising an accelerator treatment for fixing to a black matrix.