JPH0429203A - Color filter - Google Patents

Abstract

PURPOSE:To obtain the color filter which has excellent surface smoothness and good picture element accuracy and is suitable for use for a color liquid crystal display by providing light shielding frames having metallic silver and the picture elements consisting of three primary colors of light and having water-soluble ink on a light transparent substrate. CONSTITUTION:This color filter has the light shielding frames 13 having the metallic silver and the picture elements 12 which are the picture elements 12 consisting of the three primary colors B, G, R of light and having the water-soluble ink on the light transparent substrate 11. After the light shielding frames are formed of the metallic silver consisting of the reduction of a silver halide, the picture elements 12 consisting of the three primary colors B, G, R are preferably formed by printing of the water-soluble ink. The color filter which has the excellent picture element accuracy, has no projecting parts on the surface and substantially prevents the disconnection after the formation of light transparent electrodes at the time of formation of the liquid crystal display is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color filter, and particularly to a color filter that has excellent surface smoothness and is suitable for use in a color liquid crystal display.

[Background of the invention]

Some color filters are made using printing methods. According to this method, the cost is lower than that of color filters based on the so-called dyeing method or pigment dispersion method using photolithography. However, since color filters require a very large number of fine and complex pixel patterns, printing methods do not allow for adjacent patterns to overlap or for ink to fall between adjacent patterns. There was a problem with pixel accuracy due to some blank spots.

In addition, for the purpose of improving contrast, a light-shielding frame (hereinafter referred to as B
When a BM (abbreviated as M) is provided, or when the BM is produced by printing, there is a big problem in terms of printing position accuracy, as described above. Other methods of providing the BM include vapor deposition of metals or metal oxides. In these methods, the resulting color filter becomes very expensive because the positional accuracy of the BM is not good or the vapor deposition equipment used is expensive.

Therefore, a color filter that has good pixel position accuracy and is inexpensive is desired.

[Purpose of the invention]

The purpose of the present invention is to have excellent surface smoothness, good pixel precision,
The objective is to provide a color filter suitable for use in color liquid crystal displays.

[Structure of the invention]

The above object of the present invention has been achieved by a color filter having, on a light-transmissive substrate, a light-shielding frame having metallic silver and pixels consisting of three primary colors of light and having water-soluble ink.

Note that the effect of the present invention can be more effectively achieved by forming the above-mentioned light-shielding frame with metallic silver made from reduction of silver halide, and then printing pixels made of the three primary colors of light with water-soluble ink. Therefore, this is a preferred embodiment.

The light shielding frame (BM) made of metallic silver in the present invention is preferably made of metallic silver obtained by reducing silver halide.

As a method for producing such a BM made of metallic silver, for example, after producing a photosensitive material layer containing a silver halide emulsion on a light-transmitting substrate, using a mask or the like, a pattern portion that will later become the BM is coated. After exposure, the photosensitive material is immersed in a general black and white developer, and then unnecessary silver halide particles are removed by immersion in a general fixer. On this occasion,
Since it is desirable that the grain size of the developed silver to be produced be as small as possible, the silver halide emulsion used is preferably a Lippmann emulsion or the like. A more preferable method for producing BM is to use a silver complex diffusion transfer method. This method uses, for example, a photosensitive material in which a physical development nucleus layer and a negative emulsion layer are sequentially laminated on a light-transmitting substrate with an antihalation layer on the back surface, and then a BM
In areas other than the pattern areas, when exposed using a mask or the like and then developed, the silver halide forming a latent image in the exposed areas becomes blackened silver in the emulsion layer due to the action of the developing agent. This creates a negative image. At the same time, the silver halide in the unexposed area is dissolved by the action of hypomerism contained in the developer to form a silver complex salt, which is deposited as a positive image on the physical development nuclei by the reducing action of the developing agent. After this treatment, the top dead emulsion layer is removed by washing with warm water. Physical phenomenon nuclei that remain unchanged do not need to be removed or may be removed since they have virtually no absorption for visible light. The BM made of metallic silver prepared in this manner has a very fine metallic silver particle size and is very useful in the present invention.

The hydrophilic ink used in the present invention is a hydrophilic resin (polyvinyl pyrrolidone, polyamide resin (nylon resin), polyacrylic acid, etc. , polyacrylamide, borine methyl acrylamide, polyvinyl alcohol, butyral, casein, greens, gelatin, starch, etc.) and acid dyes, direct dyes, reactive dyes, and cationic dyes that are soluble in water or hydrophilic solvents.

Ratio of these dyes to hydrophilic resin (solid content) 5~
200%, preferably 10-100%, more preferably 20-709o (weight ratio). The dye and the hydrophilic resin are mixed, and the solid content is 5 to 50%, more preferably 10 to 3%.
Ink is prepared by adding water, a hydrophilic solvent (methanol, ethanol, etc.) to a concentration of 0%. A nonionic surfactant may be added to this ink as a leveling agent.

The light-transmitting substrate used in the present invention may be transparent or semi-transparent as long as it has light-transmitting properties. Furthermore, since the color filter may be exposed to high temperatures during the vapor deposition process of the transparent electrode, it is preferable that the material for the light-transmitting substrate has good corrosion resistance.

Examples of materials that make up such a light-transmissive substrate include:
Polymer compounds such as polyethylene terephthalate, polybutylene terephthalate, boristyrene, polycarbonate, polyether sulfone, polyvinyl alcohol and cellulose acetate, glass such as soda glass, borosilicate glass, and inorganic substances such as quartz and sapphire. I can list the following.

The light-transmitting substrate can be used in the form of a plate, a notebook, a film, or the like using the above-mentioned materials.

The thickness of the light-transmitting substrate can be set appropriately depending on the purpose and material, but it is usually 0.5μI11-1
It is within the range of 0mm. In particular, when glass is used as a light-transmissive substrate for a liquid crystal color display, the thickness is preferably within the range of 0.3 to 2 mm.

〔Example〕

EXAMPLES Next, the present invention will be explained in more detail with reference to Examples. Note that % in the examples represents weight % unless otherwise specified.

Example 1 A gelatin coating solution containing 0.2 g of hydroquinone, balanaum sulfide sol, and H-1 and H-2 as hardeners, 40 mg and 5 mg per Ig gelatin, respectively, was applied to 1 g of gelatin to a dry film thickness of 3 μD. So that the thickness is 1
．． 1mm transparent borosilicate glass substrate (30cm x 30cm
m) was applied.

After drying, the ortho-sensitized silver chloride emulsion containing warp grains with an average grain size of about 5 μm was processed to 1.1 μm.
A silver halide photosensitive material was prepared by coating at 5 g/m' (weight in terms of silver).

On the back side of the silver halide photosensitive material prepared in this way, M
A coating solution prepared by dissolving 102 g of the compound of -1 and the above-mentioned compounds H2 and Og in methanol 400-, ethanol 480-, and Methyl Celsolve 50Tl was applied to M-1 in an amount of 10 mg.
/dm' and then dried to form an antihalation layer.

A chromium mask for a color filter was placed on the photosensitive material (1) prepared in this way so that the exposed area was outside the BM area in Figure 1, and after exposure with a mercury lamp, silver complex salt diffusion with the following composition was applied. It was developed with a transfer developer at 23° C. for 1 minute. After removing the negative emulsion layer with warm water, the sample was immersed in a sensitizing liquid having the composition shown below for 1 minute, and then dried. In this way, BM made of metallic silver was generated only in the non-exposed portion of the physical phenomenon nucleus layer. The line width of the BM is 30 μm, and the size of the mosaic pattern is 150 μm×150 μm.

[(CH2= CH301CH2)3CCH2SO2C
)1. CH1]1NcH1cH2sO3K developer Hydroquinone Sodium sulfite (anhydrous) Sodium thiosulfate (anhydrous) Potassium bromide (anhydrous) Add aqueous benzotriazole sodium hydroxide to bring the total volume to 11'.

Liposensitizing liquid water Isopropyl alcohol 5g 0g 5g 0.5g 25mg 85g 00ml 00ml Ethylene glycol 50g 3-mercapto-4-acetamyto 5-n heptyl 1.2.4
-Triazole g On the substrate on which the BM was prepared in this way, each ink of the following composition was printed in the order of blue, red, and green so that the print size was one pixel or 180 μm x 180 μm, and the temperature was 100°C.
and dried for 10 minutes.

○Blue ink Blue 5P (manufactured by Nihon Gesou Co., Ltd.)
4g polyvinyl alcohol aqueous solution (100o) lOog
○Red ink Red 137P (Nippon Gesou Co., Ltd. 1!8ri)
5g polyvinyl alcohol aqueous solution (1098) 1
00g○ Green ink CFG-111 (manufactured by Nihon Shisou Co., Ltd.) 5g
Polyvinyl alcohol aqueous solution (10%) 100g Comparative Example 1 Same as Example-1, black ink with the following composition was printed on a transparent borosilicate glass substrate with a thickness of 1.1 mm so as to have a M pattern. After forming, blue, red, and green pixels were printed in the same manner as in Example 1 to create a color filter.

○Black ink Black 006F (manufactured by Nihon Gesou Co., Ltd.)
5g polyvinyl alcohol water solution (10%) 10
0g Comparative Example 2 According to the example disclosed in JP-A-1-150102, BM
After forming chrome by sputtering, red, green, and blue pixels were printed to create a color filter.

Example 2 The number of defective pixels with white spots was measured for each of 1000 pixels of the three types of color filters created in the above examples. Filter B (color filter created in Comparative Example-1) and color filter C (color filter created in Comparative Example-2) had 1 pixel, 300 pixels, and 1o pixels, respectively.

Example 3 Regarding the three types of color filters mentioned above,
Using Taylor Hobson's Tali Step, we determined the prominence of the edge of each pixel relative to the center of the same pixel, and found that it was 0.01 μm for color filter A, but for color filters B and C is 1 each
．． They were 7 μm and 0.4 μm. This value is the average value after measuring 30 pixels for each color filter.

〔Effect of the invention〕

The color filter of the present invention has excellent pixel accuracy as a printing method color filter, has no protrusions on the surface of the color filter, and is unlikely to cause disconnection after creating a light-transmitting electrode when creating a liquid crystal display. Yield is good. In addition, for BM created by vapor deposition such as gold vapor deposition,
Low cost.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an example of a color filter obtained by the manufacturing method of the present invention, and FIG. 2 is a cross-sectional explanatory view showing a liquid crystal color display using the color filter obtained by the manufacturing method of the present invention. . 11 Light-transmissive substrate 12... Colored portion 13-
Light shielding frame 24, color filters 25a, 25b
Polarizing plate 26・Liquid crystal 27a, 27b・=electrode example

Claims (2)

[Claims] (1) A color filter characterized by having, on a light-transmitting substrate, a light-shielding frame having metallic silver and pixels consisting of three primary colors of light and having water-soluble ink. (2) Patent claim (1) characterized in that the light-shielding frame is made of metallic silver made of reduced silver halide, and then pixels made of three primary colors of light are formed by printing water-soluble ink. ) color filters.