JPS6114483B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a color filter used in a camera of a color television image transmitting device.

Color filters used in color television cameras have conventionally been formed by depositing colored substances on a glass substrate by vapor deposition, and then formed into stripes by mechanical or chemical etching and stacked in multiple layers, or easily dyed onto the glass substrate. By repeating the process of forming and dyeing a patterned layer of resin multiple times, or by forming a resin layer on a glass substrate and selectively dyeing or bleaching that resin layer, different colored layers (color-absorbing layers) can be formed. are doing.

However, the pattern is minute in microns and is extremely difficult to manufacture. In particular, when an organic substance such as a resin is used as a colored layer, when the colored resin is made photosensitive and patterned as a colored layer, the photosensitivity and resolution are poor, and it is difficult to create a pattern with high dimensional precision and fineness. It was difficult to obtain a pattern.

The present invention was invented to correct the above-mentioned drawbacks, and involves coating an optically transparent substrate such as glass with an ordinary photoresist (thus having good resolution), drying it, and exposing it by contact or projection. Then, it is developed to form a photoresist relief image in the form of stripes or any pattern, and the concave portions of the relief image, which are non-image areas, are filled with a negative-type photosensitive resin with good dyeability that is crosslinked or hardened by light. Then, the substrate is irradiated with light from the back side and developed to form a resin layer only on the concave portions, and then immersed in a dyeing liquid to dye the resin layer. After that, the photoresist is peeled off, another photoresist is applied on top of the dyed resin layer, dried, and exposed and developed to obtain a striped or arbitrary pattern without contacting the previously dyed resin. Get relief.
The concave portion formed by this photoresist relief is filled with the same photosensitive resin with good dyeability as described above, irradiated with light from the back side, developed, and dyed at least twice, until the photoresist layer is the boundary. The resin layer is colored with different colors, such as red,
A colored layer such as green or blue is provided to form a color filter. In this method of manufacturing color filters, stripes or arbitrary patterns are not created by directly exposing a dyeable resin to light, so even if the ability to crosslink or harden with light is weak, patterning is not possible. It became possible. This is important, and in patterning, not only contact exposure but also non-contact exposure methods such as proximity or projection exposure can be used. In other words, patterning is performed using an ordinary photoresist, and the ability to crosslink or harden with light as a colored layer can be ignored, and emphasis can be placed on the original dyeing and coloring properties. As a result, it is also possible to fill the resin with a colored resin that has been colored by adding a dye or a pigment to the resin in advance. Furthermore, if patterns are adjacent to each other and there is a risk of color mixing, an appropriate coating can be formed after the photoresist is removed to prevent color mixing. Because of this kind of coating, even if the surface is uneven, non-contact exposure can eliminate defects during close contact. If a color filter is manufactured in this way, it will be extremely easy to manufacture, and
A color filter with a low defect rate and excellent color characteristics can be obtained.

The present invention will be described in detail with reference to the drawings. As shown in Fig. 1, an optically transparent substrate 1 such as an optically polished glass substrate is coated with water-soluble dyes such as acid dyes, basic dyes, and direct dyes. A dyeable photoresist, such as Situpre's AZ-
1350, positive type photoresists such as Tokyo Ohka's OFPR, polycinnamate vinyl type such as Kodatsu's TPR, negative type photoresists such as rubber type such as Hunt Chemical's Waycoat, etc., with a thickness of 3000Å to 2μ using the spin coating method. After forming a photoresist film and forming a photoresist relief image 2 by pattern exposure and development, as shown in FIG. Apply to 3000Å to 2μ. As for the coating method, spin coating method or spray method is preferable. At this time, the resin 3 on the relief image 2 becomes thinner due to its flow. The resin 3 used here may be of any kind as long as it is photosensitive and dyeable, but when using water-soluble dyes for dyeing, polyvinyl alcohol, casein, fiber glue, gelatin can be used. and at least one type of resin selected from water-soluble resins such as collagen hydrolysates, and dichromates, such as ammonium dichromate, etc., or diazonium salts, such as sulfates of P-diazodiphenylamino paraformaldehyde condensates, etc. A mixture of materials that becomes photocurable when mixed with the above-mentioned resin is used.

Next, as shown in FIG. 3, the transparent substrate 1 which is the back side
The entire surface is exposed from the side to light 4 containing a large amount of ultraviolet light such as a mercury lamp. Next, this photosensitive resin layer is developed. If this resin 3 is water-soluble, it can be developed with water. As a result of development, the resin on the photoresist relief image 2 cannot be fixed due to the unique light absorption of the photoresist, and the resin swells, and the film peels off due to development and is dragged by the photocured area and peeled off. Eventually it will flow out. Next, the fixed resin layer is immersed in a dye solution, such as a mixed solution of rose bengal and tartrazine, for 30 seconds to 2 minutes to color the resin layer red as the first color. As a result, a red colored layer 5 is formed on the resin layer as shown in FIG. Next, the photoresist relief image 2 is peeled off by spraying or showering a solvent capable of dissolving the photoresist such as photoresist thinner, such as xylene, trichlene, alcohol, etc., and at the same time, the photoresist relief image 2 is peeled off. Resin remaining in a swollen state is also removed. The results are shown in FIG. Next, move on to the second color, but if the second color does not come into contact with the first color, leave it as is; if it comes into contact with or intersect, coat it with an appropriate film to form an intermediate film to prevent color mixture,
Move on to the second color. This intermediate coating for preventing color mixing only needs to be transparent and dye-resistant, and is applied by coating with epoxy resin, acrylic resin, polyester resin, polyurethane resin, etc. in a thickness of about 500 Å to 2000 Å.

For the second color, the process of forming the first color is repeated, and a photoresist is applied, pattern exposed, and developed to form a relief image 2'. Next, the resin is filled with resin, exposed to light from the back side, developed, and dyed to form a green colored layer 6 of a second color. Subsequently, the photoresist is peeled off. By repeating this process, colored layers of various colors can be obtained. When performing pattern exposure when there is no intermediate coating to prevent color mixture,
By exposing with a space of 0.5μ or more, the photoresist acts as a mask to prevent color mixture and prevents color mixture.

Next, as an example, the case of dyeing red, green, and blue as shown in FIG. There are no restrictions and filters of any color can be manufactured.

Next, referring to the photosensitive resin with good dyeability used in the present invention, when water-soluble dyeing is used in the staining solution, water-soluble photosensitive materials have conventionally been used as resins such as natural resins such as gelatin, casein, fish glue, and egg albumin. Alternatively, water-soluble synthetic resins such as polyvinyl alcohol, polyvinylpyrrolidone, and polyacrylamide are used, but they are generally used in photosensitive materials, especially photosensitive materials made of a mixture of a resin and a photosensitizer, due to their photosensitivity, resolution, etc. The characteristics largely depend on the average molecular weight of the resin in the photosensitive material. Therefore, a photosensitive material made of a resin with a large average molecular weight has a high photosensitivity, but a poor resolution. Furthermore, when looking at the dyeability of the coating, it has the disadvantage that it has a low degree of dyeing with hydrophilic dyes and is difficult to dye. This can be easily inferred from the following. That is, when dyeing a water-soluble resin, it is known that the dyeing concentration largely depends on the ionic bond between the binding group in the polymeric substance and the dye, and that the value is determined by the number of binding groups in the resin. In this case, usable hydrophilic dyes include direct, acidic and basic dyes, but in this case, for direct and acidic dyes that have sulfonic acid groups in the molecule, amino groups participate as adsorption sites, For basic dyes that have amino groups in them, carboxyl groups are involved to form salt-forming bonds, but in the case of acidic dyes, for example, when comparing the number of amino groups in the resin, natural resins have approximately Ten
meq/g, while water-soluble synthetic resin has 0.1me
q/g, and as is clear from this value, the synthetic product can only be expected to have a staining density of about 1/10 of the natural product due to ionic bonding. Therefore, by hydrolyzing the natural resin to increase the number of its bonding groups, the dyeing density can be increased. This allows the resin coating to be made thinner for the same concentration. Therefore, resolution can also be improved. However, a decrease in photosensitivity cannot be avoided, and the exposure time is usually too long in general exposure equipment, especially projection exposure equipment, making it impractical. Another characteristic is that it is summery.

Examples of the present invention will be described below.

Example 1 Photoresist AZ on a transparent glass smooth substrate
-1350 was applied to a thickness of 1μ using a spinner, dried at 50℃ for 5 minutes, and then coated with GCA MANN TYPE4800DSW.
Reducing exposure with Stepper at 1/10 exposure time for 0.3 seconds, developing with special developer, washing with water, and then storing at 80℃
After drying for 10 minutes, a relief image having rectangular concave portions of 20 μm x 12 μm square was obtained in the form of dots. Next, Nikko Chemicals Co., Ltd.'s product name: CCP-100 (number average molecular weight 1000) is a peptide obtained by hydrolyzing collagen, which is the main protein that makes up animal bones, skin, etc. A dichromate peptide photosensitive solution, which is a dyeing resin made by mixing 100 g of collagen peptide, 100 c.c. of water, and 20 g of ammonium dichromate, was applied with a spinner at 1000 rpm, dried at 50°C for 15 minutes, and filled into the recessed areas. Ta. The film thickness was 1 μm. Next, from the back side, ultra-high pressure mercury lamp 3KW distance 70cm
The film was exposed to light for 2 minutes and developed with shower water for 1 minute.
The film thickness at that time was 0.8μ, which was a decrease of 0.2μ.
There was no resin film residue on the photoresist relief. After that, it was added to a red dyeing solution consisting of a mixture of 0.5% each of Rose Bengal and Tartrazine at 60°C.
After soaking for a minute and washing with water, the relief image of AZ-1350 was removed by spraying a methyl alcohol solution and dried at 80°C for 20 minutes. Next, as the second color, coat AZ-1350 in the same way as the first color, pattern a 20μ x 12μ square concave part 3μ apart from the first color pattern, and coat with the same resin as the first color. Similarly exposed from the back side, after development, 0.5% each of patent blue and tartrazine.
It was immersed in a green staining liquid mixture at 60°C for 2 minutes to dye it green. Next, with methyl alcohol solution
AZ-1350 was peeled off. Do the same for the third color,
Acid Violet and Truizing Blue
They were treated in the same way as the first and second colors except that they were dyed using a 0.5% mixed blue dye solution at 60℃ for 2 minutes, and each layer had a red colored layer, a green colored layer, and a blue colored layer. A matrix type color filter was obtained with a spacing of 3μ between colored layers. By the way, we investigated the resolution limit and found that the combination of the DSW stepper and AZ-1350 had a resolution equivalent to 1μ, which is the limit.

Comparative example 1 Collagen peptide CCP instead of AZ-1350
-100 and ammonium dichromate used in Example 1 was subjected to pattern exposure using a DSW stepper for the purpose of direct patterning, and the exposure was insufficient even for 4 seconds, which is the maximum exposure time of the DSW stepper. The film flowed out and no pattern could be obtained. By the way, the appropriate exposure time was approximately 20 seconds, making it a photosensitive material with extremely low sensitivity compared to normal photoresists, making it unsuitable for projection exposure.

Comparative Example 2 A photosensitive material made of polyvinyl alcohol (PVA) and ammonium dichromate instead of AZ-1350 was applied to a film thickness of 1μ for the purpose of patterning.
When pattern exposure was performed using a DSW stepper, a pattern was obtained with an exposure time of 4 seconds, but fogging occurred in the non-image areas, and the dyeing density was low at a film thickness of 1μ, and the dyeing density was the same as in Example 1. In order to achieve this, it was necessary to increase the film thickness to 10μ or more. At this time, it was difficult to resolve 30μ, making it impractical.

Example 2 A relief image was obtained using AZ-1350 in the same manner as in Example 1, and a photosensitive material made of casein and ammonium dichromate was filled into the concave portion to form a resin coating with a thickness of 1 μm. When exposed to light, developed, dyed, and peeled off with AZ-1350, a pattern with good resolution and sharpness equivalent to that of Example 1 was obtained, but the dyeing density was low; Although a film thickness of about 1.5 μm was required to achieve the same color, the other properties were good, and a color filter equivalent to that of Example 1 was obtained.

As described above, according to the present invention, a water-insoluble photoresist with excellent resolution improves the resolution and serves as a barrier to prevent the water-soluble photosensitive resin from swelling during dyeing, especially in the lateral direction. , and by means of backside exposure, it is possible to transfer a highly accurate negative pattern of the relief image of the water-insoluble resist onto the water-soluble photosensitive resin, so while the water-soluble photosensitive resin has good dyeability, it has poor resolution. Although it is generally said to be bad, as long as it has photosensitivity, fine patterns can be obtained even with a resin with low resolution. However, this manufacturing method allows the use of a projection exposure apparatus that uses a non-contact method, and because it does not involve contact exposure, it is possible to provide color filters that are resistant to dust and scratches and have a high yield.

[Brief explanation of the drawing]

FIG. 1 to FIG. 7 are explanatory cross-sectional views showing an example of the method for manufacturing a color filter of the present invention in the order of steps. DESCRIPTION OF SYMBOLS 1... Substrate, 2... Relief image, 3... Resin, 4... Light, 5... Red colored layer, 6... Green colored layer, 7... Blue colored layer.

Claims (1)

[Claims] 1. A step of forming a water-insoluble photoresist film with good resolution on an optically transparent substrate, exposing and developing the pattern to form a relief image of a predetermined pattern, and then removing a non-image of the relief image. A step of filling a dyeable water-soluble photosensitive resin into the concave portion, fixing the dyeing water-soluble photosensitive resin by exposing it to light from the back side of the substrate, and dyeing with an aqueous dye solution; A method for producing a color filter, comprising the step of peeling off a relief image of a water-insoluble photoresist, and repeating the above step at least twice. 2. The method for manufacturing a color filter according to claim 1, wherein after the step of peeling off the relief image of the water-insoluble photoresist, a step of forming an intermediate film for preventing color mixture is performed. 3. A step of forming a relief image in a predetermined pattern by forming a water-insoluble photoresist film with good resolution on an optically transparent substrate, exposing and developing the pattern, and then forming a relief image in a concave portion that is a non-image portion of the relief image. A step of filling a colored water-soluble photosensitive resin by adding a dye or pigment in advance and exposing it to light from the back side of the substrate to fix the colored water-soluble photosensitive resin, and then the water-insoluble photoresist. 1. A method for producing a color filter, comprising the step of peeling off a relief image, and repeating the above step at least twice. 4. The method for manufacturing a color filter according to claim 3, wherein after the step of peeling off the relief image of the water-insoluble photoresist, a step of forming an intermediate film for preventing color mixture is performed.