KR970003683B1 - Photosensitive resin composition for liquid crystal display color filter - Google Patents

Abstract

A sensitive resin composition for a liquid crystal display color filter having good spectroscopic feature, optical permeability, photosensitivity, resolution, smooth feature, and heat-resistant feature is disclosed. An acryl polymer resin is achieved by mixing an acryl polymer resin of 30-80 weight %, a multi-functional acryl monomer of 10-30 weight %, photo polymerization initiator of an acetophenone inducing material of 0.1-5 weight % based on a solid powder of 100 weight %, and a thiozanton of 0.1-0.5 weight % based on a multi-functional acryl monomer 100 weight %.

Description

Photosensitive resin composition for liquid crystal display color filter

1 is a cross-sectional view of the color filter panel structure,

2 is a manufacturing process diagram of the color filter,

3 is a UV-spectrum of red, green and blue pixels obtained in Example 1 and Comparative Example 1. FIG.

* Description of the symbols for the main parts of the drawings *

1: glass engine, 2: black mattress,

3: red color pixel, 4: green color pixel,

5: blue color pixel, 6: transparent protective layer.

The present invention relates to a photosensitive resin composition for liquid crystal display color filters, and more particularly to a photosensitive resin composition for color filters excellent in spectral characteristics, light transmittance, photosensitivity, resolution, smoothness and heat resistance.

Conventionally, as a photocurable resin, natural animal proteins, such as gelatin and casein, which mixed ammonium dichromate, and amine modified polyvinyl alcohol, vinylpyrrolidone-acrylic ammonium salt, and glycidyl acrylate Although the color filter was manufactured using a photoresist made by including a dye in a composition using a synthetic resin such as acryl ammonium salt, in this dyeing method, reliability of heat resistance, light resistance, etc. is weak compared to high sensitivity and resolution, and a large number of photolithography processes are used. This necessity had a disadvantage that the manufacturing cost is very high.

On the other hand, the printing method, which is an example of the manufacturing method of the color filter, can be mass-produced at a low price. However, the formed color filter has a lot of invasion of foreign substances such as dust and the surface is not smooth according to the manufacturing method. The orientation of the electrode and the alignment film is disturbed, and the threshold voltage is locally changed, thereby damaging the display quality.

In addition, a photosensitive group is introduced into a resin such as polystyrene, polyacryl, polyvinyl alcohol, polyester, polyimide, or the like is dispersed on a transparent glass substrate by dispersing the pigment in a mixed solution to which the photosensitive compound is added, and then using a photolithography process. Many pigment dispersion methods for forming a pattern in a colored layer have been studied.

However, polyimide and polyamide have good heat resistance but low color reproducibility, and polyvinyl alcohol has a weak pigment dispersibility but poor heat resistance and solvent developability.

Accordingly, an object of the present invention is to use a photosensitive resin having excellent photocrosslinkability, heat resistance, pigment dispersibility, and alkali developability, and to provide excellent optical properties for liquid crystal display color filters with excellent spectral characteristics, light transmittance, photosensitivity, resolution, smoothness, and heat resistance. To provide a composition.

In order to achieve the above object as well as another object easily expressed in the present invention by preparing a photosensitive resin composition consisting of an acrylic resin, a polyfunctional acrylate, a photopolymerization initiator, an organic solvent and a pigment containing a double bond in the side chain Color filters excellent in spectral characteristics, light transmittance, photosensitivity, resolution, smoothness and heat resistance could be obtained.

The present invention will be described in more detail as follows.

First, the acrylic polymerization resin of the following general formula (I) is 30 to 80% by weight of the solid content, 10 to 30% by weight of the polyfunctional acrylic monomer, and 0.1 to 5% by weight of the photopolymerization initiator of the acetophenone derivative. % And thioxanthone are mixed with 0.1 to 0.5% by weight of the polyfunctional acrylic monomer to obtain a photosensitive resin composition. The pigment is added to the solvent, mixed with the solvent, finely dispersed with a triple roll mill and a bead mill to prepare a color resist.

In the formula, R ₁ is hydrogen or methyl group, R ₂ is an alkyl group of 1 to 10 carbon atoms, (Wherein X = H, CI, NO ₂ or N (CH ₃ ) ₂ ) R ₃ is vinyl, allyl, acryloyl, methacryloyl or cinnamoyl. 1, m, n represents molar ratio.

Binder resin contained in the photosensitive resin composition of the present invention, that is, the basic skeleton of the acrylic resin of the general formula (I) is composed of a copolymer of an organic acid and an unsaturated organic acid ester not containing as a monomer or an organic acid ester containing a hydroxy group It is a terpolymer which is added as an essential monomer, and a photosensitive group such as vinyl, aryl, acryl, methacryl or cinnamoyl is introduced into the side chain of the basic skeleton. As the unsaturated organic acid, acrylic acid or methacrylic acid may be used, and as the unsaturated organic acid ester, aliphatic alkyl acrylate or methacrylate having 10 or less carbohydrates of an alkyl group and aromatic alkyl acrylate or methacrylate may be used. Specific examples of aromatic alkyl acrylates include phenyl acrylate, 2 or 4-chlorophenyl acrylate, 2 or 4-nitrophenyl acrylate, 2 or 4-dimethylaminophenyl acrylate, benzyl acrylate, 2 or 4-chlorobenzyl Acrylate, 2 or 4-nitrobenzyl acrylate, 2 or 4-dimethylaminobenzyl acrylate, and the like, and aromatic alkyl methacrylates include phenyl methacrylate, 2 or 4-chlorophenyl methacrylate, 2 or 4- Nitrophenyl methacrylate, 2 or 4-dimethylaminophenyl methacrylate, benzyl methacrylate, 2 or 4-chlorobenzyl methacrylate, 2 or 4-nitrobenzyl methacrylate, 2 or 4-dimethylaminobenzyl methacrylate Acrylate etc. are mentioned.

Among the resins of the general formula (I), it is particularly preferable from the viewpoint of general physical properties that the unsaturated organic acid is 5 to 40 mol%, the unsaturated organic acid ester is 60 to 90 mol%, and the organic acid ester containing a hydroxyl group is 5 to 30 mol%.

Moreover, the following compounds are mentioned as a polyfunctional acrylate or methacrylate monomer of this invention. That is, ethylene glycol diacrylate, triethylene glycol diacrylate, tetramethylene glycol diacrylate, pentaerythritol diacrylate, tetraethylene glycol diacrylate, trimethylol propane triacrylate, trimethylol triacrylate, penta Erythritol triacrylate, dipentaerythritol triacrylate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate, sorbitol triacrylate, sorbitol tetraacrylate, sorbitol hexaacrylate, trimethylol propane trimethacryl Latex, trimethylol ethane trimethacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, bis [P- (3-methacryloxypropoxy) phenyl] dimethylmethane, bis [P- (meth Chlorooxyepoxy) phenyl] dimethylmethane, sorbitol tetramethacrylate A. In addition to these monomers, prepolymers such as dimers and trimers can also be used effectively.

The photopolymerization initiator was selected by mixing two or more acetophenone derivatives and thioxanthone derivatives. Specific examples of photoinitiators of acetophenone derivatives include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,2-dimethoxy-1,2-diphenylethan-1-one, and 2-methyl. -1- [4- (ketylthio) phenyl] -2-morpholinopropane-1-one, 1-hydroxycyclohexylphenylkenone, 2-benzyl-2-dimethylamino-1- (4-morpholino Phenyl) -butan-1-one, 2,2-diethoxyacetophenone, 2,2-dimethoxyethoxy-2-phenylacetophenone, and the like, and thioxanthone derivatives include thioxanthone and 2,4-diethyl. Thioxanthone, 2-chlorothioxanthone, 2-isopropyl thioxanthone, 2-methyl thioxanthone, and the like.

When the acrylic polymer of the general formula (I) is 30 wt% or less of the solid content, the prepared photosensitive material is not applied to the organic substrate, and when 80 wt% or more, the photosensitivity is no longer improved. In addition, when the polyfunctional atryl monomer is less than 10% by weight of the solid content, the thermal decomposition temperature of the photosensitive material was low, and when it is more than 30% by weight, there was a disadvantage in poor storage, and the photopolymerization initiator was 0.1 in the solid content. In the case of the wt% or less, there was a problem in that the photoreactivity did not appear. In the case of 5 wt% or more, the photoreactivity was so large that there was a problem in storage stability. The thioxanthone derivative was 0.1 to 0.5 with respect to the polyfunctional acrylic monomer in terms of participation effect. % By weight is most preferred.

The following examples and comparative examples specifically illustrate the present invention, but the present invention is not limited thereto.

Example 1

65.3 g of 4-nitrophenyl methacrylate, 11.7 g of methyl acrylic acid, 1.52 g of 2,2-azobis (isobutyronitrile) and 220 g of ethyl acetate were added to a four-necked flask, followed by reaction at 78 DEG C for 3 hours under a nitrogen atmosphere. The precipitate was then precipitated in normal hexane to obtain a precipitate, which was dried in vacuo to obtain a white powder of 4-nitrophenyl methacrylate-methacrylate having a weight average molecular weight (Mw) of 14,700 molecular weight distribution (Mw / Mn) of 1.70 in methacrylic acid. Krylic acid copolymer was obtained.

4-necked flask with 76.0 g of 4-nitrophenyl methacrylate-methacrylic acid copolymer, 4.4 g of glycidyl acrylate, 1.2 g of triethylbenzylammonium chloride, 0.8 g of hydroquinone, 380 g of dioxane and 6 g of dimethylformamide The mixture was placed in a nitrogen atmosphere and reacted at 100 ° C. for 2 hours, followed by precipitation in hydrated ethanol to obtain a precipitate, which was dried in vacuo to obtain 20 mol% of methacrylic acid and a weight fraction molecular weight (Mw) of 16,300 molecular weight distribution (Mw / Mn) of 2.06. The powdery photosensitive acrylic resin was obtained.

8.8 g of the photosensitive acrylated acrylic resin prepared by the method described above, 4.4 g of pentaerythritol acrylate, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one 1.3 g, 0.4 g of diethyl thioxanthone, 0.007 g of hydroquinone, and 61.3 g of ethyl cellosolve acetate were dispersed in the pigments of red, green, and blue which are commonly used in the art. After spin coating at 1500 rpm for 10 seconds on the substrate and drying at 85 ° C. for 5 minutes, the xenon-mercury lamp was irradiated with a light source and developed in an aqueous alkali solution.

When the pattern is formed, it is dried for 40 minutes at 220 ℃. After repeating the above process three times, the transparent protective layer was rotated at a thickness of 1 to 2 μm at 1500 rpm, and then dried and exposed to prepare a color pixel pattern having a resolution of 2.0 μm.

Example 2

64.3 g of benzyl methacrylate, 11.7 g of methacrylic acid, 7.6 g of hydroxyethyl methacrylate, 1.87 g of 2,2'-azobis (isobutyronitrile) and 220 g of ethyl acetate were placed in a four neck flask, and After reacting for 3 hours, precipitated in normal hexane to obtain a precipitate, which was dried in vacuo to be benzyl methacrylate in a white powder state of 21 mol% of metal acrylic acid, 13,200 weight average molecular weight (Mw) and 1.62 molecular weight distribution (Mw / Mn)- Methacrylic acid-hydroxymethacrylate terpolymer was obtained.

76.0 g of benzyl methacrylate-methacrylic acid-hydroxymethacrylate terpolymer, 2.6 g of acryloyl chromite, 1.2 g of triethylamine, 0.8 g of hydroquinone and 380 g of tetrahydrofuran were prepared in the same manner as in the above method. The obtained photosensitive acrylic resin composition was treated to produce a color pixel pattern according to the process conditions described in Example 1.

Example 3

A benzyl methacrylate-methacrylic acid-hydroxymethacrylate copolymer was reacted with allyl bromide under the same conditions as in Example 2 to synthesize a photosensitive allylated acrylic resin, and the color pixel pattern was prepared according to the conditions of Example 1. Prepared.

Comparative Example 1

40.7 g of acryloyloxymethyltrimethylammonium chloride, 70.7 g of glycidyl methacrylate, 0.2 g of 2,2'-azobis (isobutyronitrile), and 500 g of methanol were reacted at 60 DEG C for 6 hours, and then a large amount. Precipitated with ethyl acetate to obtain a precipitate, washed with petroleum ether, and dried under vacuum to contain 69.3 mol% of glycidyl methacrylate, a weight average molecular weight (Mw) d1 of 50,750, and a molecular weight distribution (Mw / Mn) of 1.45. Phosphorous acrylic copolymer was synthesized. 2 g of 3,3'-diazidodiphenylsulfone and 2 g of 4,4'-diazidostilbene were added to 10 g of the acrylic copolymer thus obtained, and after dyeing, the coating was spun onto a glass substrate at 4000 rpm for 50 seconds and dried at 85 ° C. for 15 minutes. do. Next, the resultant was exposed to xenon-mercury lamp, developed with methyl ethyl ketone, rinsed with hexane, and dried to form a color filter having a resolution of 2 μm after drying at 150 ° C. for 30 minutes.

Comparative Example 2

30 g of benzyl methacrylate-methacrylic acid copolymer (73/27), 7.7 g of pentaerythritol tetraacrylate, 4-pN, N-di (ethoxycarbonylmethyl) -2,6-di (trichloromethyl) 0.3 g of -s-triazine, 0.01 g of hydroquinone monomethyl ether and 62 g of ethyl cersolve acetate were mixed to obtain a photosensitive resin composition, and a color filter was prepared according to the process conditions described in Example 1.

Physical properties were evaluated using the color filters prepared in Examples 1 to 3 and Comparative Examples 1 and 2, and the results are shown in Table 1.

TABLE 1

Physical property evaluation of color filter

* Spectral characteristics: UV spectrum of red, green and blue (added to Figure 3)

Chemical resistance: Soak at 25 ℃ for 30 minutes and heat at 170 ℃ for 2 hours

Heat resistance: Observation of transmittance and surface condition after heating at 200 ℃ for 4 hours

Sensitivity: Use xenon-mercury lamp of 365nm

As described above, the color filter using the composition of the present invention was particularly superior in spectral characteristics, chemical resistance, heat resistance, color reproducibility, and the like to the conventional color filter.

Claims (4)

30 to 80% by weight of the solid content of the acrylic polymer resin of the general formula (I), 10 to 30% by weight of the solid content of the polyfunctional acrylic monomer, 0.1 to 5% by weight of the solid content of the photopolymerization initiator of the acetophenone derivative And thioxanthone are mixed by 0.1 to 0.5% by weight of a polyfunctional acrylic monomer, and the photosensitive resin composition for a liquid crystal display color filter. In the above formula, R ₁ is hydrogen or methyl, R ₂ is an alkyl group of 1 to 10 carbohydrates, (Wherein X = H, C1, NO ₂ or N (CH ₃ ) ₂ ) R ₃ is vinyl, allyl, acryloyl, methacryloyl or cinnamoyl, and 1, m, n represents a molar ratio . The acrylic resin according to claim 1, wherein the acrylic resin of the general formula (I) is a copolymer of an unsaturated organic acid and an unsaturated organic acid ester as a monomer or a tripolymer to which an organic acid ester containing a hydroxyl group is added as an essential monomer. The photosensitive resin composition for a liquid crystal display color filter, characterized in that it comprises a double bond in the side chain of the basic skeleton. 3. The unsaturated organic acid according to claim 2, wherein the unsaturated organic acid is acrylic acid or methacrylic acid in the range of 5-40 mol%, and the unsaturated organic acid ester is an aliphatic alkyl acrylate or methacrylate having an alkyl group of 10 or less carbohydrates and an aromatic alkyl acrylate or The organic acid ester containing the hydroxy group in the range of 60-90 mol% in methacrylate, and the range of 5-30 mol% as 2-hydroxyethyl methacrylate. The photosensitive resin composition for liquid crystal display color filters. The photosensitive resin composition for a liquid crystal display color filter according to claim 2, wherein the photosensitive group is a vinyl, aryl, acryloyl, methacryloyl or cinnamoyl group.