JPS5942281B2 - Molding method of fine pattern color filter film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a finely patterned color filter film, for example, a color filter film used in a single-tube image pickup tube, such as Trinikon (trade name).

First, in order to facilitate understanding of the present invention, a conventional method for forming a finely patterned color filter film will be explained with reference to FIG.

As shown in FIG. 1A, a dyeing medium layer dyed in a predetermined color, for example, green G, is entirely deposited on a substrate such as glass.
Next, the dyeing medium layer 2 is decolorized except for the part where a green fine pattern is to be finally obtained. Therefore, a decolorizing mask 3 is deposited on the dyeing medium layer 2 in a pattern corresponding to the green micropattern to be finally obtained. This decolorizing mask can be formed into a predetermined pattern by using a photoresist, for example, by applying a photoresist over the entire surface, exposing it to light, and developing it. Next, as shown in FIG. 1B, using this mask layer 3 as a mask, the dyeing medium layer 2 is subjected to a decoloring process.

When such decolorization is performed, the media layer 2 that has swelled due to dyeing contracts due to the decolorization, so that the depressed portion 4
is formed. In this case, since the bleaching agent for decolorization also diffuses laterally through the window 3a of the mask layer 3, a depressed portion 4 is created which penetrates under the periphery of the window 3a. Next, as shown in FIG. 1C, the medium layer 2 is dyed with another color, for example, red R, through the window 3a of the mask layer 3.

In this way, a green color filter section 5G having a green fine pattern and a red color filter 5R having a red fine pattern.
A color filter film 5 is obtained in which . 5 However, the color filter film 5 obtained by such a method is
As explained in FIG. There is a drawback that the pattern extends into the area where the pattern 5G is to be formed, making it difficult to obtain a filter having a highly accurate pattern.

It is an object of the present invention to provide a method for forming a finely patterned color filter film that is free from such drawbacks.

An example of the present invention will be explained in detail with reference to FIG.

First, as shown in FIG. 2A, a dyeing medium layer 2 dyed in a predetermined color, for example, green, is deposited on a substrate 1 made of glass or the like, as shown in FIG. to adhere to. This dyeing medium layer 2 is made by exposing and curing gelatin mixed with ammonium dichromate to exhibit photosensitivity, as described above, and applying a first color such as a green dye such as cyan and yellow dyes. For example, as a cyan dye, ``5'' acid dye Acid Brilliant Milling Green (trade name, manufactured by Sumitomo Chemical Co., Ltd.) or Batent Blue (
(trade name, manufactured by Daiichi Kasei Co., Ltd.); similarly, as the yellow dye, the acidic dye Supranor Yellow 1 R (trade name, manufactured by Bayer AG) may be used. Then, on this dyeing medium layer 2, a decolorizing mask 3 having a window 3a in a portion where a pattern of the second color is to be formed is formed. This decolorization mask 3 can be made by, for example, applying a photoresist using a photographic technique, that is, coating the entire surface of the resist, curing it by exposure to light, etc.
It is deposited by development. Next, as shown in Figure 2B,
Using the decolorizing mask layer 3 as a mask, the dyeing medium layer 2 is decolorized using, for example, potassium permanganate as a decolorizing agent (bleaching agent). This avoids bleaching the entire thickness of the medium layer 2 under the window 3a through the window 3a, and limits the bleaching work to a portion.

That is, the decolorization is prevented from penetrating under the periphery of the window 3a, or in other words, the depressed portion 4 due to decolorization is prevented from penetrating under the periphery of the window 3a. Thereafter, as shown in FIG. 2C, a decolorizing mask layer 13, such as a photoresist of a photosensitive curing type, is deposited on the decolorizing mask layer 3.

In this case, it is particularly formed to cover the inner circumferential surface 4a of the depressed portion 4.
The decolorizing mask 13 can be attached to the circumferential surface 4a of the depressed portion without using any special method.In forming the decolorizing mask 13, an exposure process is performed using the same exposure mask as the previously formed decolorizing mask 3. If this is done, the peripheral surface of the portion having the recessed portion 4 will be exposed to light by fogging, so that when this portion is hardened and a development process is performed, the mask layer 13 will remain attached to this portion. Next, as shown in FIG. 2D, the decolorizing portion 2a of the medium 2 at the bottom of the recessed portion 4 is further decolorized using the mask 13 as a decolorizing mask, and the entire thickness of the medium 2 below the recessed portion 4 is The color is removed over a long period of time.

When bleaching is performed in this way, the area around the depression 4 is covered with a mask 13.
Since the decolorization progressing in the horizontal direction can be effectively suppressed, the pattern of the decolorized portion should be carried out along the thickness direction of the medium 2 with almost no spread in the horizontal direction. This is something that can be done. Then this staining medium 2
The decolorized portion 2a is dyed with a second color, for example, blue B.

In this case, it is possible to dye the bleached area directly with blue dye, but it is difficult to dye the item once it has been bleached, so a new dye can be applied to the bleached area. It may be desirable to apply a dyeing medium and dye this, for example, in blue. To explain an example of this case, as shown in FIG. 2E, a new medium 12, for example, a layer of material made of gelatin mixed with ammonium dichromate, is applied entirely within the recessed portion 4, including on the mask layer 13. and board 1
Exposure processing is performed from the back side. Thus, in the area with the green dyeing pattern G, the light transmission is low, so that the layer 12 deposited on this area is not sufficiently exposed to light, resulting in a depression or depression on the bleached area. Only layer 12 within section 4 is fully exposed. Therefore, when this medium 12 is then dyed blue as shown in FIG. 2F, the exposed portion of the medium 12, that is, within the depression 4, is sufficiently dyed. As this blue dye, an acidic dye such as Supranor Cyanine G (manufactured by Bayer AG, trade name) can be used.
Thereafter, as shown in FIG.
Remove 3 and 3. In this way, the desired color filter film 5 having a green color filter section 5G by the green staining G and a blue color filter section 5B by the blue staining B can be obtained. As described above, according to the manufacturing method of the present invention, the decoloring work is not performed all at once, but is stopped midway, and the mask 1 is placed on the inner circumferential wall of the recessed portion 4.
3 to continue bleaching, this mask 13 can prevent the progress of bleaching to the side, allowing high-precision bleaching of the desired pattern, and making it possible to form fine patterns with high precision. A color filter film having a color filter portion can be obtained.

Further, as in the above-described embodiment, when a new medium 12 is newly formed and a fine pattern of the second color, that is, a fine pattern of blue is to be formed thereon, it is necessary to dye the medium well. It is possible to obtain a color filter film with good characteristics.

In the above example, the present invention is applied to form a color filter having a fine pattern of green and blue, but other color combinations, not only two colors but three colors, etc. It is obvious that the present invention can be applied to color filters to achieve similar effects.

[Brief explanation of the drawing]

FIGS. 1A to C are process diagrams of a conventional method for forming a finely patterned color filter film, and FIGS. 2A to G are enlarged cross sections of each step showing an example of the method for forming a finely patterned color filter film according to the present invention. It is a diagram. 1 is a substrate, 2 and 12 are dyeing medium layers, 3 and 13 are decolorization masks, 4 is a decolorization depression, 4a is an inner peripheral surface thereof, and 5 is a color filter film.

Claims (1)

[Claims] 1. In a method for forming a color filter film with a fine pattern by depositing a dyeing medium layer dyed in a predetermined color on a substrate and decolorizing a predetermined portion of the dyeing medium layer, during the decoloring step described above, A method for forming a finely patterned color filter film, comprising: forming a decoloring mask on the inner circumferential surface of the recessed portion of the decolorized portion, and then continuing decolorization.