JP2590858B2 - Color filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

 Purpose of the invention

[Industrial applications]

The present invention relates to a color filter, particularly to a color filter for a liquid crystal color display panel.

[Prior art]

It is used for color filters, especially for liquid crystal color display panels. It is arranged on a transparent support such as a glass substrate or a plastic film, with red, green and blue coloring patterns arranged in a predetermined regularity. It is manufactured by providing it at the boundary portion and the adjacent portion of the display screen and at the outer peripheral portion of the display screen. This black pattern fills the gaps between the red, green, and blue coloring patterns, improves the contrast and saturation of the displayed image, becomes a light-shielding material for the opposite substrate such as TFT made of amorphous silicon, and shields the outer periphery of the screen. Also works as a mask. Heretofore, as a means for forming the black pattern, there are a method of forming a metal thin film as a light shielding layer, a method of printing with a black ink, and a method of forming a resist pattern by a photolithography method and then dyeing it black. However, each of these methods requires a step of forming a black pattern in addition to a step of forming a red, green, and blue coloring pattern, and this complicated step has hindered a reduction in manufacturing cost.

[Problems to be solved by the invention]

An object of the present invention is to provide a color filter with a black pattern at a low cost by taking the current state of the technology as described above one step further and adopting a simpler configuration. Structure of the invention

[Means to solve the problem]

The color filter of the present invention basically comprises, on a transparent support, red, green, and blue color patterns and a black pattern, and a black pattern disposed on the outer peripheral portion of the screen. In a color filter formed by superimposing three or two color layers of red, green and blue on a pattern, a black pattern disposed at a boundary portion and an adjacent portion of the red, green and blue color patterns is red. , Green and blue color layers are superposed, and the black pattern on the outer peripheral portion of the screen is formed by superposing two color layers of red and blue. A preferred embodiment is characterized in that in the above color filter, a transparent coating material is applied on the red, green, and blue coloring patterns and the black pattern to reduce unevenness on the surface of the color filter.

[Operation]

Referring to the drawings, the color filter 1A (1B) of the present invention
Will be described together with its manufacturing process. In the basic embodiment of the present invention, as shown in FIG. 1, first, for example, a red translucent coloring layer 31 as a first color is formed on a transparent support 2 such as a glass substrate or a plastic film. The pattern is formed as follows. It is preferable to apply a transparent covering material as the intermediate layer 71 thereon. Next, as shown in FIG. 2, on the intermediate layer 71, a green translucent coloring layer 32 as a second color is formed in a predetermined pattern. Further, as shown in FIG. 3, an intermediate layer 72 is provided thereon, and a blue translucent coloring layer 33 as a third color is formed on the intermediate layer 72 in a predetermined pattern. The part where the superimposed coloring layers are only one layer each,
Red, green, and blue coloring patterns, and a portion where three colors are superimposed become a black pattern 5. Thus, the color filter 1A is completed. The portion of the black pattern 5 formed by the superposition of the three colored layers has a large difference in film thickness from the portion of the monochromatic colored pattern. The thickness of the monochromatic layer is usually 1 to 1.5
μm, the thickness of the black pattern 5 is 3 to 4.5 μm
And the roughness of the film surface reaches 2-3 μm. Large irregularities on the surface of the color filter are not preferable because, for example, an appropriate cell gap cannot be obtained at the time of assembling the liquid crystal cell. Therefore, in a preferred embodiment of the present invention, a transparent coating material also serving as a protective layer of the color pattern,
A color filter 1B having a thickness of 1 μm or more, preferably about 2 μm to form a protective layer / transparent coating material layer 8 and reduce surface irregularities to about 0.5 to 1 μm.
Get. The black pattern 6 on the outer periphery of the screen usually has a width of about 1 mm, and since the width of the black pattern in the screen is usually 10 μm or less, if a transparent coating material is applied as it is, the protection over the black pattern on the outer periphery of the screen The layer / transparent covering material layer 8 becomes thicker than the other portions, which hinders the reduction of surface irregularities. Therefore, only the black pattern 6 on the outer periphery of the screen is formed as a pseudo black by superimposing the two colors of the red coloring layer 31 and the blue coloring layer 33 without superimposing the three colors, and reducing the total film thickness of this portion. Make the surface as flat as possible.

[Example 1] A glass substrate "# 7059" having a thickness of 1.1 mm (Corning)
Then, gelatin having photosensitivity imparted with dichromate was applied by a spin coating method, exposed through a predetermined mask, and then developed to obtain a pattern having a cross section shown in FIG. This pattern was dyed with a red acid dye to form a red coloring layer 31. The film thickness was 1 μm. After dyeing, this colored layer
A thermosetting acrylic resin was applied as a middle layer 71 on the 31 by a spin coating method to a thickness of 0.1 μm. For the second color, gelatin was applied in the same manner as the first color, exposed through a predetermined mask, and developed to obtain the pattern shown in FIG. This pattern was dyed with a green acid dye to form a green colored layer 32. The film pressure was 1 μm. An intermediate layer 72 having a thickness of 0.1 μm was applied also on the coloring layer 32. As a third color, gelatin is similarly coated, exposed through a predetermined mask and developed to obtain a pattern shown in FIG. 3, and this pattern is dyed with a blue acid dye to form a blue coloring layer 33. Formed. This film thickness was also 1 μm. The roughness of the surface of the obtained color filter 1A is about 2μ.
m, and the optical density of the black portion obtained by superimposing the three colors is 2.
It was five.

Example 2 A thermosetting acrylic resin was applied as a protective film to a thickness of 2 μm on the color pattern and the black pattern of the color filter formed in the same manner as in Example 1, and a color filter having a cross section shown in FIG. 1B was obtained. The surface roughness of the obtained color filter was reduced by 1 μm or less. The optical density of the black portion obtained by superimposing the three colors was 2.5, which was the same.

【The invention's effect】

Although the color filter of the present invention omits the step of forming a black pattern, it works in the same way as the conventional one. The increase in the surface irregularities due to the change in the structure was performed without increasing the number of working steps by devising the pattern shape and increasing the thickness of the protective layer. Therefore, the color filter of the present invention can be manufactured with conventional equipment, and can enjoy the advantage of cost reduction by simplifying the operation.

[Brief description of the drawings]

FIG. 1 to FIG. 4 are explanatory views of the steps of the method for manufacturing a color filter of the present invention. FIG. 1 shows a state in which a first color layer and an intermediate layer are formed on a glass substrate. FIG. 2 shows a state in which a second color layer is similarly formed, and FIG. 3 shows a state in which a second intermediate layer and a third color layer are formed, that is, a basic mode of the present invention. FIG. 4 shows a state in which a protective layer and a transparent coating material layer are formed, that is, a step in which a color filter of a preferred embodiment of the present invention is manufactured. 1A, 1B color filter 2 transparent support 31 red color layer 32 green color layer 33 blue color layer 5, 6 black pattern 71, 72 intermediate layer 8 protection Layer and transparent coating layer

Claims (2)

(57) [Claims] A color pattern of red, green, and blue and a black pattern are arranged on a transparent support, and a black pattern is arranged on an outer peripheral portion of a screen.
In a color filter formed by superimposing three or two color layers of red, green, and blue, black patterns disposed at the boundary portions and adjacent portions of the red, green, and blue color patterns are red, green, and blue. A color filter, wherein three blue color layers are formed by superimposition, and a black pattern on an outer peripheral portion of the screen is formed by superimposing two color layers of red and blue. 2. The color filter according to claim 1, wherein a transparent coating material is applied on the red, green, and blue coloring patterns and the black pattern to reduce irregularities on the surface of the color filter. .