JPH08201617A - Resin composition for transparent thin film and formation of transparent thin film - Google Patents

Abstract

PURPOSE: To improve the adhesion, resistance to heat and chemicals, coating film property, etc., by using the reaction product of the styrene-maleic anhydride copolymer and amine as the curing agent. CONSTITUTION: The resin composition for a transparent film consists of an epoxy resin, curing agent and org. solvent, and the curing agent is the reaction product of the styrene-maleic anhydride copolymer and amines. A copolymer shown by the formula is exemplified as the styrene-maleic anhydride copolymer. In the formula, (a) and (b) are respectively a natural number of 1 to 3, (a)>=(b) and (a+b)=2 to 4. Aniline, N-methylaniline, etc., are exemplified as the amines, and especially a primary amine having an aromatic group such as aniline and benzylamine is preferably used. The reaction product is formed by bonding the amines to a part or the whole of the maleic anhydride part of the copolymer, and the bonding rate is controlled to 10-90%, preferably to 20-80% and more preferably to 30-70%.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a resin composition for a transparent thin film and a method for forming a transparent thin film, and particularly useful for forming a protective film or a flat layer on a colored resin film formed on the surface of a glass substrate or the like. It is something.

[0002]

2. Description of the Related Art Among flat panel displays, the development of liquid crystals has been remarkable, and color liquid crystals have been mounted on notebook computers and workstations one after another.
With the development of color liquid crystals, the demand for materials constituting color liquid crystal display devices is also increasing. When producing this color liquid crystal display element, a color filter is provided on a transparent substrate such as glass, an inorganic thin film made of ITO (indium, tin, oxide) or the like is formed on this, and then a transparent electrode is formed by a photolithography method. The mainstream method is to form an alignment film of polyimide or the like on this and arrange the liquid crystal.

However, since a color filter without an overcoat film is insufficient in heat resistance and chemical resistance to withstand the process of forming ITO by vapor deposition of a transparent electrode, a method of forming a protective film on the color filter. Is the mainstream. Properties required of this color filter protective film include heat resistance and chemical resistance, as well as adhesion to a substrate and a color filter, smoothness, transparency and the like. Further IT
It is also an important property that there is no coloring due to heat in the heat treatment when forming O or the alignment film. The material for these protective films is mainly composed of an epoxy resin and a curing agent. As the epoxy resin, a glycidyl ether compound of a phenol compound is used, and as the curing agent, a novolac resin such as phenol or o-cresol is used.

[0004]

However, the above-mentioned curing agents have problems in producing a color liquid crystal display element in terms of coloring by heat treatment, adhesiveness with a substrate, and the like, and improvement thereof is desired. The present invention provides a resin composition for a transparent thin film and a method for forming a transparent thin film, which are excellent in adhesion, heat resistance (the degree of change in the degree of coloring before and after heat treatment is small), chemical resistance, coating property and the like. To aim.

[0005]

The inventors of the present invention have accomplished the present invention as a result of intensive studies to solve the above-mentioned problems. That is, the present invention provides (1) a transparent thin film resin composition comprising an epoxy resin, a curing agent and an organic solvent, wherein the curing agent is a reaction product of a styrene / maleic anhydride copolymer and an amine. A resin composition for a transparent thin film, (2) a resin composition for a transparent thin film according to (1) above, wherein the amine is benzylamine or aniline, (3) for a transparent thin film according to (1) to (2) above A cured product of a resin composition, (4) a transparent thin film which is formed by applying the resin composition for a transparent thin film according to the above (1) to (2) to a surface of a substrate and curing the same by heating. Thin film formation method, (5)
The method for forming a transparent thin film according to (4) above, characterized in that the coating is performed on the surface of the base material coated with the colored resin film.

In the present invention, the reaction product of the styrene / maleic anhydride copolymer polymer and the amine used as the curing agent is obtained by reacting the styrene / maleic anhydride copolymer polymer with the amine in an organic solvent. It is obtained by Examples of the styrene-maleic anhydride copolymer polymer include those represented by the general formula (2)

[0007]

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(Here, a and b are natural numbers of 1 to 3 respectively, a is the same as or larger than b, and a + b is 2 to 2).
It is 4. ) And a styrene / maleic anhydride copolymer polymer. This polymer is, for example, G
SM / 601, GSM-602, GSM-603 (all are trade names: manufactured by Gifu Shellac Co., Ltd.) have a / b of 1 /
It is commercially available as a copolymer of 1, 2/1, 3/1 and the like. Examples of the organic solvent include alkylene glycol monoethyl ether such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monoisopropyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and propylene glycol monoisopropyl ether acetate. Alkyl ether acetate, methoxypropionic acid ester, ethoxypropionic acid ester, alkoxypropionic acid ester such as isopropoxypropionic acid ester and the like can be mentioned. Examples of amines include primary or primary amines such as aniline, N-methylaniline, N-ethylaniline, P-n-butylaniline, benzylamine, tert-butylamine, 2-ethylhexylamine, di-2-ethylhexylamine and the like. Examples thereof include secondary amine compounds, and primary amines having an aromatic group (eg, phenyl group) such as aniline and benzylamine are particularly preferable. The styrene / maleic anhydride copolymer polymer and amines are used in a molar ratio of the former to the latter of about 0.1 to 0.9, preferably 0.2 to 0.8.
It is a degree. The reaction may be performed at 50 to 150 ° C. for about 8 to 20 hours.

The reaction product of the styrene / maleic anhydride copolymer polymer and amines produced by the above reaction is one in which amines are bound to a part or all of the maleic anhydride moiety in the polymer, The binding rate is 10-9
0%, preferably 20-80%, more preferably 30
~ 70% is preferable, for example, the following general formula (1)

[0010]

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(Where a is the same as above, and b ₁ , b ₂
Is a natural number of 0 to ₁ , and b ₁ + b ₂ is b (b
Is the same as the above) and X represents a residue of a primary or secondary amino group). In addition, b ₂ is 0.
1 to 1, preferably about 0.2 to 0.8.

The resin composition for a transparent thin film of the present invention comprises the above-mentioned curing agent, epoxy resin and organic solvent, and a curing accelerator is used in combination if necessary. Examples of the epoxy resin include polyfunctional epoxy resins, which are glycidyl ether compounds of polyphenol compounds such as bisphenol A, bisphenol F, trishydroxyphenylmethane, and pyrogallol, and glycidyl ether compounds such as phenol novolac resins and cresol novolac resins. A glycidyl ether compound of a polyphenol compound is preferable from the viewpoint of colorability at the time. Any organic solvent can be used as long as it does not participate in the curing reaction, and is not particularly limited, but ethyl cellosolve acetate, isopropyl cellosolve acetate, butyl cellosolve acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate. , Diglyme, ethylene glycol diacetate, etc., preferably having a boiling point of 100 ° C. or higher. These may be used alone or as a mixture. 1-cyanoethyl-2-ethyl-4 as a curing accelerator
-Methylimidazole, 2-Ethyl-4-methylimidazole, 2-Isopropylimidazole, 2-Phenylimidazole, 1-Benzyl-2-methylimidazole, 2-Phenyl-4-methylimidazole, Triphenylphonphine, Diazabicycloundecene-7, Trimellitic anhydride Acids and the like can be used, but are not limited to these.

The cured product of the resin composition for a transparent thin film of the present invention can be obtained, for example, by heating and curing the resin composition. Specifically, for example, a method for forming a transparent thin film is to dissolve an epoxy resin, a curing agent, and, if necessary, a curing accelerator in an organic solvent, spin coating, roll coating or the like to form a colored resin film or a glass plate. Apply to the substrate to be applied,
Heat treatment, curing treatment, or the like is performed, and an oven, a hot plate, or the like is used as a curing method. For example, in the case of a hot plate, it is preferable to pre-bake at 70 to 100 ° C. for 1 to 10 minutes to remove the solvent, and then post bake at 140 to 250 ° C. for 1 to 60 minutes to cure. Further, the curing temperature does not have to be constant, and for example, curing may be performed while raising the temperature.

By thus curing, a transparent thin film having a film thickness of preferably 0.1 to 10 μm, more preferably 0.2 to 3 μm and having good adhesion and excellent smoothness can be obtained. The transparent thin film of the present invention has high heat resistance (coloring resistance), adhesion, and chemical resistance. Therefore, the present invention is particularly applicable to a transparent thin film (protective film for a colored resin film) on a colored resin film such as a color filter for liquid crystal display. It is particularly useful when forming a film or forming a smooth layer of the same color filter. In addition, the transparent protective film of the present invention can be used as an overcoat of printed matter, wood, metal, synthetic resin and the like.

The content ratio of each component in the present invention is such that when the reaction product of the styrene / maleic anhydride copolymer polymer and amines is 100 parts by weight, the epoxy resin content is 50 to 50 parts by weight.
300 parts by weight, preferably 75 to 150 parts by weight.
The curing accelerator is 0.1 to 10% by weight with respect to the epoxy resin.
Parts, preferably 0.5 to 5% by weight. The solid content is dissolved in an organic solvent to prepare a transparent thin film resin composition, and the solid content is 5 to 60% by weight, preferably 10 to 50% by weight.

Further, a leveling agent, an adhesion improver, an antioxidant, an ultraviolet absorber and the like may be added to the resin composition of the present invention to the extent that transparency is not impaired.

[0017]

EXAMPLES The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Synthesis Example 1 Styrene / maleic anhydride copolymer GSM-601 (a
/ B = 1/1, manufactured by Gifu Shellac Co., Ltd.) 180 g (0.
89 mol) and 34.7 g (0.374 mol) of aniline were charged into 1100 g of ethylene glycol monoisopropyl ether acetate, and stirred at a reaction temperature of 100 ° C. for 15 hours to obtain a target product (aniline-modified resin liquid). The acid value of this product was 97, and the reaction rate (actually measured acid value / theoretical acid value of maleic anhydride half amide relative to charged amine × 10
0) was 99%.

Synthesis Example 2 40.0 g of benzylamine was added to aniline in Synthesis Example 1.
The same treatment was performed except that the amount was changed to (0.374 mol) to obtain the desired product (benzylamine-modified resin liquid). The acid value of this product was 93, and the reaction rate was 98%.

Example 1 80.0 g of the aniline-modified resin liquid obtained in Synthesis Example 1, 23.2 g of epoxy resin (VG-3101, Epoxy equivalent 213, manufactured by Mitsui Toatsu Chemicals, Inc.), 5.3% PSC- 11
(Curing accelerator; Nippon Kayaku Co., Ltd.) 8.75 g of ethylene glycol monopropyl ether acetate 23.
It was dissolved in 2 g and filtered through a 0.1 μm membrane filter to obtain a resin liquid. The nonvolatile content of the obtained solution is 29.9.
It was the weight% (140 degreeC, 1 hour oven heat processing).

Next, the sample solution thus obtained was treated with 5c.
m coating on a glass substrate at 1000 rpm for 15 seconds, followed by drying on a hot plate having a surface temperature of 80 ° C for 5 minutes, then heating at 100 ° C for 3 minutes, and then at 200 ° C for 2 minutes.
Heat treatment was performed for 0 minutes to obtain a transparent thin film having a film thickness of 2.0 μm.
The transparent thin film thus obtained was heat-treated at 230 ° C. for 30 minutes, and the degree of coloring after the heat treatment was examined with a spectrophotometer. The transmittance at 450 nm was 97.6%.
The chromaticity difference before and after the heat treatment was 0.13.

Example 2 The same operation was carried out except that the sample solution obtained in Example 1 was applied to a chromium substrate instead of the glass substrate. The resulting coating film on the chromium substrate was dipped in 18% hydrochloric acid and 5% sodium hydroxide for 30 minutes, washed with water and dried, and then subjected to a cross-cut test (according to JIS K 5400) to obtain a coating film after acid and alkali treatment. The adhesion test with the substrate was performed. No peeling was observed in both acid and alkali treatments.

Example 3 80.0 g of the benzylamine-modified resin liquid obtained in Synthesis Example 2,
Epoxy resin used in Example 1 23.8 g, 5.3%
9.0 g of PSC-11 was dissolved in 23.8 g of propylene glycol monomethyl ether acetate, and the obtained solution was pressure filtered using a 0.1 μm membrane filter to obtain a resin liquid. The nonvolatile content of the obtained resin liquid was 30.6%.

Next, the sample solution thus obtained was spin-coated on a glass substrate at 1000 rpm for 15 seconds, dried on a hot plate having a surface temperature of 80 ° C. for 5 minutes, and then heated at 100 ° C. for 3 minutes, Further, it was heat-treated at 200 ° C. for 20 minutes to obtain a transparent protective film having a thickness of 2.0 μm. The transparent thin film thus obtained was heat-treated at 230 ° C. for 30 minutes, and the degree of coloring after the heat treatment was examined with a spectrophotometer. 450
The transmittance in nm was 97.4%. The chromaticity difference before and after the heat treatment was 0.12.

Example 4 The same operation was carried out except that the sample solution obtained in Example 3 was applied to a chromium substrate instead of the glass substrate. The resulting coating film on the chromium substrate was dipped in 18% hydrochloric acid and 5% sodium hydroxide for 30 minutes, washed with water and dried, and then subjected to a cross-cut test (according to JIS K 5400) to obtain a coating film after acid and alkali treatment. The adhesion test with the substrate was performed. No peeling was observed in both acid and alkali treatments.

Comparative Example 1 Instead of the aniline-modified resin liquid of Synthesis Example 1 in Example 1, orthocresol novolac (weight average molecular weight 10
Sample solution was prepared in the same manner except that (00) was used.
Then, the subsequent operations were performed in the same manner as in Example 2, and the adhesion between the substrate and the film was examined by a cross cut test. The result was 70/100, and 30% of peeling was observed.

[0027]

INDUSTRIAL APPLICABILITY The resin composition for a transparent thin film and the method for forming a transparent thin film of the present invention have excellent adhesion to a colored resin formed on a substrate such as a glass plate, and have good leveling property and heat resistance. When an epoxy resin or the like is cured on the transparent thin film, its adhesion is excellent, and its reliability can be improved especially in a color liquid crystal display device.

Claims (5)

[Claims] 1. A resin composition for a transparent thin film comprising an epoxy resin, a curing agent and an organic solvent, wherein the curing agent is styrene.
A resin composition for a transparent thin film, which is a reaction product of a maleic anhydride copolymer polymer and an amine. 2. The resin composition for a transparent thin film according to claim 1, wherein the amine is benzylamine or aniline. 3. A cured product of the resin composition for a transparent thin film according to claim 1. 4. A method for forming a transparent thin film, which comprises applying the resin composition for a transparent thin film according to claim 1 or 2 onto a surface of a substrate and curing the resin by heating to form a transparent thin film. 5. The method for forming a transparent thin film according to claim 4, wherein the coating is performed on the surface of the base material coated with the colored resin film.