JP3232709B2 - UV curable resin composition and color filter protective film using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultraviolet curable resin composition and a protective film for a color filter using the composition.

[0002]

2. Description of the Related Art Transparency, adhesion, spatter resistance, coating properties, heat resistance, and the like are required as characteristics required for a resin for a protective film of a color filter, and a (meth) acrylic resin (for example, JP-A-60-216307), epoxy resin (for example, JP-A-4-97102), and polyimide-based resin (for example, JP-A-1-2292).
No. 03) has been studied. Of these resins, (meth) acrylic resins have the highest transparency,
It has been widely studied. However, these resins, including (meth) acrylic resins, have some problems in balancing adhesion, spatter resistance, heat resistance, and the like. Many proposals have been made to improve these points. For example, JP-A-60-216307 and JP-A-4-97100 disclose a method of forming a cured film by mixing a polycarboxylic anhydride with an epoxy group-containing polymer and performing a crosslinking reaction by heating. However, in order to carry out the reaction by mixing a high molecular compound and a strong low molecular weight compound, unreacted polycarboxylic anhydride remains to form a non-uniform layer, which is undesirable because the physical properties are reduced. .

[0003] On the other hand, polyimide resins have the disadvantages that they are inherently inferior in transparency and require high-temperature heating when the film is cured. In addition, it is necessary to remove the protective film around the color filter substrate in the process, which is currently performed using a resist. Recently, Japanese Unexamined Patent Publication No.
No. 74, JP-A-4-164970 and the like disclose a color filter protective film using an ultraviolet curable resin composition. However, these are all unfavorable in operation because the developer is a highly toxic organic solvent.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to irradiate ultraviolet rays through a mask after pre-baking, and to carry out development using a less toxic developing solution instead of a conventional highly toxic organic solvent. An object of the present invention is to provide an ultraviolet curable resin composition capable of obtaining a possible coating film. Also,
An object of the present invention is to provide a color filter protective film which is not deteriorated in physical properties and is excellent in transparency, heat resistance, chemical resistance, spatter resistance, adhesion and the like.

[0005]

As a result of various studies, the present inventors have found that the use of a specific ultraviolet-curable resin composition satisfies the required characteristics of the color filter protective film and that the color filter protective film has a low toxicity and a weak alkaline property. The inventors have found that etching can be performed with an aqueous solution, and have completed the present invention. That is,

The ultraviolet-curable resin composition of the present invention is characterized by containing the following four components (A), (B), (C) and (D). (A) General formula (I)

Embedded image And a structural unit represented by the general formula (II)

Embedded image An epoxy group-containing (meth) having a structural unit represented by the following as a main structural unit, and having an intrinsic viscosity at 30 ° C. of 0.05 to 1 in diethylene glycol dimethyl ether:
Acrylic copolymer. (B) A (meth) acrylic polymer containing one or more of a carboxylic acid group and a polycarboxylic anhydride group having an intrinsic viscosity at 30 ° C. of 0.05 to 1 in diethylene glycol dimethyl ether. (C) A monomer having a (meth) acryl group. (D) a photopolymerization initiator. (However, in the general formulas (I) and (II), R ¹ and R ² are each independently a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, and m represents an integer of 1 to 4).

[0007] The color filter protective film of the present invention is obtained by applying a UV curable resin composition containing the above four components (A), (B), (C) and (D) to a substrate, Pre-baking, irradiating ultraviolet rays, etching if necessary, and post-baking as necessary.

[0008] In a preferred embodiment of the ultraviolet curable resin composition of the present invention, the component (A) comprises glycidyl methacrylate and N
-Vinyl-2-pyrrolidone as a main component, and the component (B) is methyl methacrylate (hereinafter referred to as M
MA), methacrylic acid (hereinafter referred to as MA).
) And maleic anhydride (hereinafter M
Abbreviated as AH) as a main component,
MMA and a copolymer containing MA as a main component, or MM
It is a copolymer containing A and MAH as main components.

The components (A) and (B) can be easily synthesized by ordinary radical polymerization. Both of these components and (C) a monomer having a (meth) acryl group, (D)
The ultraviolet curable resin composition of the present invention can be produced by mixing a photopolymerization initiator, mixing additives such as a coupling agent as needed, and dissolving the same in an organic solvent.

The component (A) used in the present invention has the following general formulas (III) and (IV)

Embedded image

Embedded image (However, in the general formulas (III) and (IV), R ¹ and R ² are each independently a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, and m is an integer of 1 to 4). Can be easily obtained by copolymerizing the monomer represented by the formula (1) in the presence of a radical polymerization initiator. Of these, a combination of glycidyl methacrylate and N-vinyl-2-pyrrolidone is most preferred. In this case, another (meth) acrylic monomer or a small amount of a vinyl monomer may be added to carry out copolymerization in order to improve properties such as solubility and adhesion of the obtained polymer. Of these, glycidyl methacrylate and N-
The combination of vinyl-2-pyrrolidone is most preferred.

Other (meth) acrylic monomers include methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, 2-ethoxyethyl acrylate and 2-hydroxyethyl acrylate. Acid esters or methacrylic acid esters such as methyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, benzyl methacrylate, 2-hydroxypropyl methacrylate And the like. Other vinyl monomers include styrene, p-hydroxystyrene, α-methylstyrene and the like.

The proportion of these monomers in the polymer is as follows: the monomer represented by the general formula (III): 30 to 90% by weight;
It is 10 to 70% by weight of the monomer represented by (IV), 0 to 30% by weight of another (meth) acrylic monomer and 0 to 30% by weight of a vinyl monomer. As a part of another (meth) acrylic monomer or vinyl monomer, a monomer having a carboxylic acid group or a polycarboxylic anhydride group described below within 10% by weight can be added. The component (A) can be easily obtained by subjecting the above monomer to a polymerization reaction in a reaction solvent in the presence of a radical polymerization initiator according to a conventional method. The polymerization degree of the obtained copolymer is preferably such that the intrinsic viscosity at 30 ° C. in diethylene glycol dimethyl ether is in the range of 0.05 to 1. Below this range, the physical properties of the protective film for the color filter deteriorate, and above this range, the solubility in a solvent decreases, and the selection range of the solvent is unfavorably limited.

The reaction solvent used here includes ketones such as methyl ethyl ketone, methyl isobutyl ketone and methyl cyclohexanone, ethers such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether. And esters such as ethylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether acetate, and diethylene glycol monoethyl ether acetate.

As the radical polymerization initiator, benzoyl peroxide, t-butylperoxybenzoate,
Examples thereof include organic peroxides such as lauroyl peroxide and azobisisobutyronitrile.

The component (B) which contains at least one of a carboxylic acid group and a polycarboxylic acid anhydride group (meth)
The acrylic polymer is composed of 10 to 70% by weight of a monomer having a carboxylic acid group or a polycarboxylic anhydride group, 30 to 90% by weight of another (meth) acrylic monomer described above,
If necessary, it can be obtained by mixing another vinyl-based monomer in an amount of 30% by weight or less and conducting polymerization using the above-mentioned solvent and radical polymerization initiator according to a conventional method.

Here, the above-mentioned epoxy group-containing (meth) acrylic monomer can be added within a range of 10% by weight or less as the (meth) acrylic monomer. Further, as a monomer having a carboxylic acid group or a polyvalent carboxylic anhydride group used in the synthesis,
(Meth) acrylic monomers such as acrylic acid and methacrylic acid, maleic anhydride, citraconic anhydride, 2,2
3-dimethylmaleic acid, 1-cyclohexane anhydride
1,2-dicarboxylic acid, ethyl maleic anhydride, anhydrous 2
And maleic anhydride derivatives such as -methyl-3-ethylmaleic acid and 2,3-diethylmaleic anhydride.

The polymerization degree of the polymer of the component (B) is preferably such that the intrinsic viscosity at 30 ° C. in diethylene glycol dimethyl ether is in the range of 0.05 to 1. Below this range, the physical properties of the color filter protective film decrease, and above this range, the solubility in solvents decreases,
It is not preferable because the selection range of the solvent is limited.

Examples of the monomer having a (meth) acryl group as the component (C) include the following compounds, but are not necessarily limited thereto. Butyl acrylate, cyclohexyl acrylate, dimethylaminoethyl methacrylate, benzyl acrylate, carbitol acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, 2-hydroxylethyl acrylate, 2-hydroxyethyl Methacrylate, 2-hydroxypropyl acrylate, 2-hydroxylpropyl methacrylate, glycidyl methacrylate, N-methylolacrylamide, N-diacetoneacrylamide, N, N'-methylenebisacrylamide, N-vinylpyrrolidone, Ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, butylene glycol diacrylate, butylene glycol Cole dimethacrylate, neopentyl glycol diacrylate, neopentyl glyco-
Rudimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate,
1,6-hexanediol-dimethacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate,
Pentaerythritol tetra (3-mercaptopropionate), pentaerythritol (mercaptoacetate), glycerol acrylate / methacrylate and the like.

Examples of the photopolymerization initiator of the component (D) include, but are not necessarily limited to, the following compounds. Benzophenone, Michler's ketone, 4,4′-diethylaminobenzophenone, xanthone, thioxanthone, isopropylxanthone, isopropylthioxanthone, 2,4-diethylthioxanthone, 2-ethylanthraquinone, acetophenone,
2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methyl-4'-isopropylpropiophenone, 1-hydroxycyclohexylphenyl ketone, isopropylbenzoin ether, isobutylbenzoin ether, 2,2-diethoxy Acetophenone,
2,2-dimethoxy-2-phenylacetophenone, benzyl, camphorquinone, benzuanthrone, 2-methyl-1- {4- (methylthio) phenyl} -2-morpholino-1-propan-1-one, 2-benzyl- 2
-Dimethylamino-1- (4-morpholinophenyl)
-Butanone-1,3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, N-phenyl-glycine, p-hydroxy-N-phenylglycine, tetramethylthiuram monosulfide, tetramethylthiuram Disulfide, p-tolyl disulfide, 4
Ethyl-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 3,3′-carbonyl-bis (7
-Diethylamino) coumarin, 2,6-bis (p-azidobenzylidene) cyclohexanone, 2,6-bis (p
-Azidobenzylidene) -4-methylcyclohexanone, 2,6-bis (p-azidobenzylidene) -4-t
-Butylcyclohexanone, ethyl-p- (N, N-dimethylamino) benzoate and the like.

When these components (A), (B), (C) and (D) are mixed, any combination of compounds that dissolve in each other can be used as it is as the composition of the present invention. However, in general, in order to improve coating properties, it is preferable to dissolve these compounds in an organic solvent and use them as a coating solution. As the organic solvent, the above reaction solvents can be used in any mixing ratio. (A) (B) The mixing ratio of both components is that the epoxy group in the component (A) and the carboxylic acid group in the component (B) (the carboxylic acid anhydride group is calculated as two carboxylic acids) are close to equivalent. Is preferred, but not so strict. The component (C) comprises (A) and (B)
The amount is preferably from 20 to 300 parts by weight, particularly preferably from 50 to 200 parts by weight, per 100 parts by weight of the total amount of the components. If the amount is less than this, curing by ultraviolet rays is insufficient, and if it is more than this, the physical properties of the cured film deteriorate. (D) component is (C) component 10
1 to 50 parts by weight and 5 to 20 parts by weight are particularly preferable with respect to 0 parts by weight. If the amount is less than this, curing by ultraviolet rays is insufficient, and if it is more than this, the stability over time of the coating solution is undesirably reduced.

In addition to these, if necessary, the polymer 20
% By weight or less of a crosslinking aid, a coupling agent, and a thermal polymerization inhibitor can also be added. As the crosslinking aid, a compound containing a hydroxyl group, a carboxyl group and an amino group is used. Silane, aluminum and titanate compounds are used as a coupling agent for improving the adhesion to the substrate. Specific examples thereof include silanes such as 3-aminopropyltriethoxysilane, 3-aminophenyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-methacryloxypropyltrimethoxysilane; Examples thereof include aluminum such as isopropylate and titanate such as tetraisopropylbis (dioctylphosphite) titanate, but are not necessarily limited thereto. Hydroquinone, p-methoxyphenol, and the like are used as the thermal polymerization inhibitor.

Next, a method for forming a cured film using the ultraviolet curable resin composition of the present invention will be described. The ultraviolet curable resin composition of the present invention is applied on a color filter patterned on a glass substrate by a known method such as spin coating, dipping or spray printing to form a coating film. The coating film is prebaked at a temperature of 30 to 150 ° C. using a heating means such as an electric furnace or a hot plate to remove most of the solvent in the coating film. A negative mask is placed on the coating film and irradiated with actinic radiation. X for actinic radiation
Examples include rays, electron beams, ultraviolet light, and visible light, and ultraviolet light and visible light are particularly preferred. Then, if necessary, a relief pattern is obtained by dissolving and removing the unexposed portion with a developing solution. As a developer, sodium hydroxide, potassium hydroxide, sodium carbonate,
A weakly alkaline aqueous solution such as sodium hydrogen carbonate or tetraammonium hydroxide can be used. If necessary, rinsing can be performed in a non-solvent. 150-300 ° C. by the above-mentioned heating means in order to promote the curing of the polymer of the relief pattern formed by development.
Preferably, post-baking can be performed at a temperature of 180 to 250 ° C.

Further, the ultraviolet-curable resin composition of the present invention is applied to a substrate such as a silicon wafer, a metal plate, a plastic plate or the like by a known method such as spin coating, dipping or spray printing to form a coating film. By performing pre-baking and post-baking in the same manner as in the formation of the color filter protective film, a cured film can be formed, which can be used for flattening a substrate of an electric component.

Hereinafter, the present invention will be described specifically with reference to Synthesis Examples and Examples, but the present invention is not limited to these Synthesis Examples and Examples. The “parts” in the examples below are all “parts by weight”. The intrinsic viscosity of the polymer is 3 in diethylene glycol dimethyl ether solution.
It was measured at 0 ° C.

Synthesis of Epoxy Group-Containing (Meth) acrylic Polymer {Component (A)} (Synthesis Example 1) 40 parts of glycidyl methacrylate (hereinafter abbreviated as GMA), N-vinyl-2-pyrrolidone (hereinafter, referred to as GMA)
20 parts of VP) and 2 parts of azobisisobutyronitrile (hereinafter abbreviated as AIBN) were dissolved in 300 parts of methyl ethyl ketone, and then dissolved at 60 ° C. for 4 hours.
Subsequently, polymerization was performed at 80 ° C. for 12 hours. The obtained reaction solution was transferred into a large amount of n-heptane to precipitate a polymer,
After being filtered off, dried under reduced pressure in a vacuum dryer at 50 ° C. for 24 hours.
A copolymer (referred to as AI) was obtained. The intrinsic viscosity of the obtained copolymer was 0.095.

(Synthesis Example 2) 20 parts of GMA, 25 parts of VP
Parts, 5 parts of MMA, and 2 parts of AIBN were dissolved in 300 parts of methyl ethyl ketone in the same manner as in Synthesis Example 1 to obtain a copolymer (A-II) having an intrinsic viscosity of 0.14.
I got

Synthesis of (meth) acrylic polymer {component (B)} containing one or more of carboxylic acid groups and polycarboxylic anhydride groups (Synthesis Example 3) 30 parts of MA and 70 parts of MMA Division and AI
Synthesized in the same manner as in Synthesis Example 1 except that 1 part of BN was dissolved in 300 parts of diethylene glycol dimethyl ether,
A copolymer (BI) having an intrinsic viscosity of 0.18 was obtained.

(Synthesis example 4) 30 parts of MAH, 10 parts of MA
Parts, 50 parts of MMA, 10 parts of styrene, and AIB
Synthesized in the same manner as in Synthesis Example 1 except that 1 part of N was dissolved in 300 parts of methyl ethyl ketone, and the intrinsic viscosity was 0.14.
(B-II) was obtained.

Example 1 A polymer (A) was used as the component (A).
36 parts of (I), 64 parts of polymer (BI) as component (B), 120 parts of pentaerythritol triacrylate as component (C), and 2-methyl- as component (D).
5 parts of 1- {4- (methylthio) phenyl} -2-morpholinopropane-1, 5 parts of ethyl-p- (N, N-dimethylamino) benzoate, 3 parts of isopropylthioxanthone and a silane coupling agent ( 5 parts of Chisso Corporation (S510) was dissolved in 300 parts of diethylene glycol dimethyl ether (abbreviated as DIG) as a solvent to prepare an ultraviolet-curable resin composition.

This resin composition is applied on a glass plate,
Prebaking was performed for 20 minutes on a hot plate maintained at 0 ° C. to form a coating film. These coating films were exposed through a mask for 20 seconds with an ultra-high pressure mercury lamp (20 mw / cm @ 2).
These were developed by immersing them in a developer containing 2% sodium carbonate for 2 minutes, and rinsed with water. 2 more
When post-baking was performed for 1 hour in an oven at 00 ° C., there was no residual film in the unexposed area, and a transparent film remained in the exposed area. Separately, after the entire surface was exposed under the same conditions, post-baking was performed without dipping in a developer to form a coating film.

A film obtained by immersion in the post-exposure developer and a film obtained without immersion in the post-exposure developer, that is, each film thickness depending on the presence or absence of development was measured, and the remaining film ratio was measured by the following equation. The results are shown in Table 1. Remaining film ratio = {film thickness after exposure (with development) / film thickness after exposure (without development)} × 100 Next, transparency, adhesion to a substrate, and chemical resistance required for a color filter protective film. , Heat resistance and spatter resistance were measured. In addition, the physical properties of a resin composition obtained by mixing an epoxy group-containing polymer with a low molecular weight acid anhydride are shown as Comparative Example 1. Table 1 shows the results.

The properties required for the color filter protective film were measured by the following methods, and the results are shown in Table 1. (Transparency) The light transmittance was measured with a spectrophotometer UV-210A manufactured by Shimadzu Corporation, and the light transmittance at a wavelength of 400 nm was shown. (Heat resistance) Transparency after heat treatment at 250 ° C. for 3 hours was shown. (Chemical resistance) N-methyl-2-pyrrolidone solution at room temperature
It was fixed vertically for 0 minutes and immersed, and it was determined whether or not the boundary between the part immersed in the liquid and the part immersed in the liquid could be visually identified. When the boundary line was visible, it was evaluated as x, and when it was not, it was evaluated as ○. (Sputter resistance) When an ITO film (indium oxide) having a thickness of 200 Å at 200 ° C. was formed on the cured film by sputtering, the presence or absence of wrinkling of the film was examined. When there was a wrinkle, it was x, and when it was not, it was x. (Adhesion) A cut was made on the cured film to make 100 1-mm-square small pieces, and a cellophane tape was attached to the surface thereof and immediately peeled off. At that time, when there was peeling of the cured film together with the cellophane tape, it was evaluated as x, and when it did not, it was evaluated as ○.

Examples 2 to 4 Except that the components such as the components were prepared as shown in Table 1,
In the same manner as in Example 1, an ultraviolet curable resin composition was prepared. Table 1 shows the measurement results of the properties of the composition and the properties required for the color filter protective film.

Comparative Example 1 A resin composition was obtained in the same manner as in Example 1 except that the components shown in Table 1 were used without using the components (B), (C) and (D) and a crosslinking agent. Was. Table 1 shows the measurement results of characteristics required for the color filter protective film of the composition.

[0035]

[Table 1]

From the results of the properties of the compositions shown in Table 1, it is clear that the coating film obtained from the resin composition of the present invention can be developed with an aqueous alkali solution.

[0037]

The coating film obtained from the resin composition of the present invention can be developed with an aqueous alkali solution, and the cured film has the necessary properties of a color filter protective film such as transparency, heat resistance and chemical resistance. It satisfies all of spatter resistance and adhesion, and it is clear that the resin is suitable for this application.

Continuation of the front page (51) Int.Cl. ⁷ identification symbol FI G02B 5/20 101 G02B 5/20 101 G03F 7/004 511 G03F 7/004 511 7/038 503 7/038 503 (56) References JP JP-A-4-270714 (JP, A) JP-A-4-180064 (JP, A) JP-A-1-128064 (JP, A) JP-A-61-292604 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) G03F 7/11 501 C08G 59/20 C08G 59/40 C08L 63/00 G02B 5/20 G02B 5/20 101 G03F 7/004 511 G03F 7/038 503

Claims (3)

(57) [Claims] 1. An ultraviolet curable resin composition comprising the following four components (A), (B), (C) and (D). (A) General formula (I) And a structural unit represented by the general formula (II): An epoxy group-containing (meth) having a structural unit represented by the following as a main structural unit, and having an intrinsic viscosity at 30 ° C. of 0.05 to 1 in diethylene glycol dimethyl ether:
Acrylic copolymer. (B) A (meth) acrylic polymer containing one or more of a carboxylic acid group and a polycarboxylic anhydride group having an intrinsic viscosity at 30 ° C. of 0.05 to 1 in diethylene glycol dimethyl ether. (C) A monomer having a (meth) acryl group. (D) a photopolymerization initiator. (However, in the general formulas (I) and (II), R ¹ and R ² are each independently a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, and m represents an integer of 1 to 4). 2. The component (A) wherein the structural unit represented by the general formula (I) is derived from glycidyl methacrylate,
The structural unit represented by the general formula (II) is derived from N-vinyl-2-pyrrolidone, and the component (B) is
Methyl methacrylate, a copolymer obtained from methacrylic acid and maleic anhydride, a copolymer obtained from methyl methacrylate and methacrylic acid, or a copolymer obtained from methyl methacrylate and maleic anhydride The ultraviolet-curable resin composition according to claim 1. 3. An ultraviolet-curable resin composition containing the following four components (A), (B), (C) and (D) is applied to a substrate, prebaked if necessary, and irradiated with ultraviolet light. A color filter protective film obtained by etching and post-baking as necessary. (A) General formula (I) And a structural unit represented by the general formula (II): An epoxy group-containing (meth) having a structural unit represented by the following as a main structural unit, and having an intrinsic viscosity at 30 ° C. of 0.05 to 1 in diethylene glycol dimethyl ether:
Acrylic copolymer. (B) A (meth) acrylic polymer containing one or more of a carboxylic acid group and a polycarboxylic anhydride group having an intrinsic viscosity at 30 ° C. of 0.05 to 1 in diethylene glycol dimethyl ether. (C) A monomer having a (meth) acryl group. (D) a photopolymerization initiator. (However, in the general formulas (I) and (II), R ¹ and R ² are each independently a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, and m represents an integer of 1 to 4).