JPH0679087B2 - Color filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color filter.

[Prior art]

Conventionally, a color filter using a photosensitive resin has been manufactured by the following method. That is, a photosensitive water-soluble resin is first coated on a support, and after development after exposure, a relief image is obtained. Then, the water-soluble resin is dyed to form a colored layer having desired spectral characteristics.

Examples of the photosensitive water-soluble resin include natural proteins such as glue, gelatin, and casein-dichromic acid-based, or polyvinyl alcohol, polyvinyl cinnamate-based water-soluble polymer-dichromic acid-based dichromate photoresist. Mainly used (JP-A-47-37237, JP-B-5)
3-248, JP-A-57-139712, and JP-A-58
-97007 publication).

Further, as a method of forming a colored image using a non-dichromic acid type photoresist, a copolymer of diacetone acrylamide 20 to 90 mol% and acrylamide 10 to 80 mol% as described in JP-A-57-168248 is used. There is a method of using a water-soluble resin containing

[Problems to be solved by the invention]

However, the above-mentioned conventional technique has various problems as described below.

Natural proteins such as glue, gelatin, and casein have large variations in molecular weight distribution. Therefore, photosensitivity and dyeability are unstable, and process control is difficult.

Water-soluble polymer films such as polyvinyl alcohol and polyvinyl cinnamate are weak against heat and lose their transparency and discolor when heat of 150 ° C or higher is applied. When the transparent electrode is formed, the temperature is about 200 ° C. Therefore, when such a material is used for the color filter, the transparent electrode cannot be formed on the color filter.

The above-mentioned natural protein and water-soluble polymer-dichromic acid type photoresist are prone to dark reaction, and chromium is toxic, and thus requires a large amount of cost for storage and wastewater treatment facilities.

The diacetone acrylamide-acrylamide copolymer-diazo resin system does not have the above-mentioned problems, but has a problem that it has poor adhesion to a glass substrate or a hydrophobic transparent resin. Therefore, for example, it is difficult to put it into practical use in a color filter having a laminated structure having a colored layer, an intermediate layer and a protective layer.

Therefore, the present invention solves such a problem, and: -Adhesion between the color filter and the transparent glass substrate and the hydrophobic transparent resin is good.

-The color filter, especially its colored layer, has excellent heat resistance.

・ Manufacturing is possible under stable process conditions.

-The toxicity of the chemicals used is low, and color filters can be manufactured in a safe manufacturing process. Further, the management of chemicals and the treatment of waste liquid become relatively easy.

The aim is to produce a color filter which has many advantages such as.

[Means for solving problems]

The color filter of the present invention comprises a support, a photosensitive material comprising a water-soluble resin and a photocrosslinking agent, and a transparent resin,
In the color filter, the photosensitive material is disposed on the support, and the photosensitive material is colored with a dye to form a colored layer, and a protective layer made of a transparent resin is further disposed on the colored layer. The water-soluble resin is an acrylate monomer having a tertiary amino group-containing side chain of 10 to 80 mol.
%, An acrylate monomer having a hydroxyl group-containing side chain 10 to 80
The photo-crosslinking agent is a diazo compound or an azide compound.

[Action]

According to the above configuration of the present invention, the water-soluble copolymer resin contains a diazo compound or an azide compound as a photocrosslinking agent, whereby the photocrosslinking agent and a side group containing aquatic group in the copolymer undergo photoreaction. It is possible to form a high resolution relief image.

Since the above copolymer is water-soluble, the unexposed area can be easily removed with water. On the other hand, the tertiary amino group-containing monomer in the copolymer thus obtained can serve as an adsorbing part for a water-soluble acid dye. Therefore, by coloring the image with an acid dye having a desired spectral characteristic, a colored layer having a desired shape and spectral characteristic can be formed. In addition, since the above-mentioned copolymer contains methacrylic acid ester in its monomer composition, it exhibits good adhesion to the hydrophobic resin and the glass substrate. Further, the translucency of the above resin does not change even after being heated at 250 ° C. and is excellent in heat resistance. Since the above copolymer is a synthetic polymer, it is possible to obtain one having a very uniform molecular weight distribution.

Thus, by using the above copolymer as the coloring layer, a relief image can be formed by water development, and by dyeing with an acid dye, it has good adhesion to the glass substrate and the hydrophobic transparent resin, and heat resistance. It is possible to obtain a colored layer having excellent properties.

Furthermore, since a diazo compound or an azide compound is used as the photo-crosslinking agent, there is no problem of toxicity as in the case of using chromium, the process for obtaining the above colored layer is safe, and the management of chemicals and waste liquid treatment are easy. Will be things.

Example 1 FIG. 1 is a diagram showing the structure of a color filter of Example 1 according to the present invention. This embodiment will be described below with reference to FIG.

As a water-soluble resin, N, N-dimethylaminopropylmethacrylamide 45 mol% as a monomer having a tertiary amino group-containing side chain, 2-hydroxyethyl methacrylate 50 mol% as a monomer having a hydroxyl group-containing side chain, Methyl methacrylate 5mol as acrylic ester monomer
% Copolymer was used. Next, p as a photo-crosslinking agent
-A condensation product of diazodiphenylamine and formaldehyde was added in a proportion of 10.0 wt% with respect to the above copolymer.

The copolymer-diazo compound aqueous solution was applied to the transparent glass substrate 1 by spin coating, dip coating, roll coating or the like to have a thickness of about 1 μm, preliminarily dried, and then exposed to ultraviolet rays using a mask having a predetermined shape. After developing with warm water at about 40 ℃ and drying,
Immersed in a red acid dye bath at 80 ℃, and colored layer 2 of red
Got Next, an acrylic transparent resin was coated as an intermediate layer 3 (dye-proof layer) to form a film.

The above steps are sequentially repeated to form the green dyeing layer 4, the intermediate layer 5, and the blue coloring layer 6, the acrylic transparent resin is used to form the protective layer 7, and the ITO film 8 is provided as a transparent electrode on the protective layer 7 to make it active. A mosaic color filter for matrix color liquid crystal display was obtained.

Here, the monomer composition of the water-soluble resin is not limited to that of this example. For example, as the acrylate having a tertiary amino group-containing side chain, N, N-dimethylaminoethyl acrylate, N, N-diethylaminoethyl acrylate, N, N-dimethylaminoethyl methacrylate, N, N-dimethylaminopropyl acrylamide , N, N
-Such as dimethylaminopropyl methacrylamide.

Further, examples of the monomer having a hydroxyl group-containing side chain include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 2-hydroxypropyl methacrylate.

On the other hand, the photo-crosslinking agent is not limited to that of this example, and various azide compounds or diazo compounds can be used. Condensation product of 2,5-dimethoxy-4-P tolylmercaptonbenzenediazonium or 2,5-dimethoxy-4-morpholinobenzenediazonium and formaldehyde, 4,4-diazidostilbenzene-
Examples thereof include sodium 2,2-disulfonate and 2,6-bis (4-azidobenzal) acetone 2-sulfonic acid.

According to the color filter of the present invention, since the water-soluble resin is photocrosslinked by the diazo compound or the azide compound as described above, there is no problem of dark reaction such as chromium,
Storage of the mixture is also easy. Furthermore, since it has low toxicity, it is highly safe from the viewpoint of storage and wastewater treatment.

Further, in the above water-soluble resin, the monomer that contributes to photocrosslinking and the monomer that contributes to dyeing are independent of each other, and their composition can be arbitrarily controlled, so that the exposure step hardly affects the dyeing step, and the dyeing It is possible to make the time constant. Therefore, management of the dyeing process has become very easy.

Further, since methyl methacrylate is contained in the polymer chain, it has good adhesion to the intermediate layers 3 and 5 and the protective layer 7 in the color filter laminated structure, and does not peel during dyeing. Further, it is not necessary to use a surfactant or the like for maintaining close contact with the dyed layer, the intermediate layer and the protective layer.

Furthermore, the water-soluble resin used in the color filter of the present invention has excellent heat resistance because its basic structure is acrylic,
It does not lose its transparency up to a temperature of 0 ° C.

As described above, the color filter using the present water-soluble resin can be manufactured in a safer and simpler process as compared with the conventional one. Further, it was found that the obtained color filter has excellent adhesion between the laminated layers in the structure and is also resistant to heat.

[Embodiment 2] FIG. 2 is a sectional view of a stripe color filter in the present embodiment 2. This embodiment will be described below with reference to FIG.

An ITO film was formed as a transparent electrode on a transparent glass substrate, and etching was performed using a photoresist to form a stripe-shaped transparent ITO electrode 2.

Water-soluble resin N, N-dimethylaminoethyl acrylate 50mol%, 2-hydroxyethyl methacrylate 4
Using a copolymer consisting of 0 mol% and 10 mol% of methacrylic acid, a condensate of P-diazodiphenylamine and formaldehyde was added at 10 wt% to the above copolymer to prepare a mixed solution.

Next, the mixed solution was coated on the electrode-attached substrate by dip coating, roll coating, spin coating or the like to a thickness of about 0.5 μm. After pre-drying, UV exposure is carried out using a predetermined mask, followed by hot water development at 40 ° C. and drying to obtain a relief image. The substrate having this relief image was dipped and dyed in a red dyeing solution at about 80 ° C. to obtain a red colored layer 3. A transparent acrylic resin film was formed as the intermediate layer 4 on the colored layer. Then, a green colored layer 5, an intermediate layer 6 and a blue colored layer 7 were formed by the same method as described above, and finally a protective layer 8 was formed to obtain a color filter for a simple matrix liquid crystal color display.

Also in this embodiment, the manufacturing process is a safe and stable process as in the first embodiment.

Furthermore, the common electrode 2, the intermediate layers 4 and 6, the protective layer 6 and the colored layers 3 and 5,
Adhesion with 7 is good, and it is not necessary to apply a surfactant such as a silane coupling agent.

Further, in this example, the colored layers 3, 5, 7 having sufficient color density could be obtained even if the coat film thickness was as thin as 0.5 μm. This is because the ratio of the monomer containing the tertiary amino group, which is the dyeing seat of the water-soluble resin, in this example is as high as 50 mol%, so that the dyeing property is sufficient even if the film thickness is thin. There is.

When this color filter is used for a simple matrix liquid crystal panel, an electric field is applied from the transparent electrode 2 to the liquid crystal layer through the colored layers 3, 5, and 7, at which time an electric field drop occurs in the colored layer.
There is a problem that the effective electric field is lowered.

However, the color filter of this embodiment has the colored layers 3, 5,
It was found that the above-mentioned problems can be almost eliminated because 7 can be made thinner. Therefore, by using this color filter, it is possible to obtain a color liquid crystal panel with lower power consumption and sufficient color characteristics.

Example 3 FIG. 3 is a sectional view of a color filter of this example.
This embodiment will be described below with reference to FIG.

A transparent glass substrate 1 was coated with a water-soluble resin-diazo compound mixture using the copolymer having the same composition as in Example 1 and dried. After the whole surface was exposed to ultraviolet rays and dried, a positive resist having dyeing resistance was coated on the film. After exposure to ultraviolet light using a predetermined mask and development, red dyeing was performed to obtain a red colored layer 2. The positive resist was peeled off with a weak alkaline solution, the mask position was changed, and the above steps were sequentially repeated to form a green colored layer 3 and a blue colored layer 4. Next, an ITO film 6 was formed as a transparent electrode to obtain a mosaic color filter.

It was found that when the positive resist is peeled off in a weak alkaline solution in the manufacturing process of this color filter, there is no desorption of the dye, and therefore the usual formaldehyde or hardening treatment such as tannic acid treatment can be eliminated. .

In the case of natural proteins such as gelatin, those having primary, secondary, and tertiary amino groups coexist as an acidic dye adsorption portion. However, the primary and secondary amino groups release H ⁺ in an alkaline solution and become nonionic groups, so that it becomes impossible to adsorb the acid dye by Coulomb force. Therefore, it causes the detachment (crying) of the dye.

However, since the tertiary amino group does not become a nonionic group even in an alkaline solution, desorption of the dye hardly occurs. As described above, in the water-soluble resin in this example, the dye bleeding hardly occurs, and the preventive treatment can be omitted.

〔effect〕

As described above, according to the color filter of the present invention, a support, a photosensitive material comprising a water-soluble resin and a photocrosslinking agent, and a transparent resin, the photosensitive material is disposed on the support, Further, in the color filter in which the light-sensitive material is colored with a dye to form a colored layer, and a protective layer made of a transparent resin is further disposed on the colored layer, the water-soluble resin is a tertiary amino group-containing side. A photo-crosslinking agent, which is a copolymer comprising 10 to 80 mol% of an acrylate monomer having a chain, 10 to 80 mol% of an acrylate monomer having a hydroxyl group-containing side chain, and 0 to 20 mol% of an acrylate ester monomer. Since it is a diazo compound or an azide compound, it is possible to obtain a color filter having a colored layer which has good adhesion to a substrate such as a hydrophobic resin and glass and has excellent heat resistance.

Further, since the diazo and azide compounds can be used as the cross-linking agent, the effects of dark reaction and chromium toxicity can be solved.

Moreover, since the step of strengthening the adhesion of a surfactant or the like and the step of film hardening for preventing crying out can be omitted, there is an effect that the manufacturing step can be greatly simplified.

Further, there is an effect that a practical color density can be obtained with a thinner film thickness. Since the water-soluble resin in the present color filter has a high resolution, it is sufficiently possible to form a color image pickup tube by using a solid-state image pickup element for the support.

[Brief description of drawings]

FIG. 1 shows a sectional view of a mosaic color filter in Example 1 of the present invention. 1: Transparent Glass Substrate 2: Red Colored Layer 3, 5: Intermediate Layer 4: Green Colored Layer 6: Blue Colored Layer 7: Protective Layer 8: ITO Film FIG. 2 is a sectional view of a striped color filter in an example of the present invention. Indicates. 1: Transparent glass substrate 2: Transparent electrode 3: Red colored layer 4, 6: Intermediate layer 5: Green colored layer 7: Blue colored layer 8: Protective layer FIG. 3 is a cross section of the mosaic color filter in Example 3 of the present invention. The figure is shown. 1: Transparent glass substrate 2: Red colored layer 3: Green colored layer 4: Blue colored layer 5: Protective layer 6: ITO film

Claims (1)

[Claims] 1. A support, a photosensitive material comprising a water-soluble resin and a photocrosslinking agent, and a transparent resin. The photosensitive material is disposed on the support, and the photosensitive material is a dye. In a color filter which is colored to form a colored layer, and a protective layer made of a transparent resin is further disposed on the colored layer, the water-soluble resin is an acrylate monomer having a tertiary amino group-containing side chain. ˜80 mol%, a acrylate monomer having a hydroxyl group-containing side chain 10 to 80 mol%, and an acrylic acid ester monomer 0 to 20 mol%, and the photocrosslinking agent is a diazo compound or an azide compound. A color filter characterized by that.