JP2003026889A - High refractive index resin composition for coating and its cured product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a thermosetting resin composition which gives a cured product having a high refractive index, excellent heat resistance, excellent adhesivity, excellent hardness, excellent solvent resistance and excellent transparency, and is suitable for optical materials such as clear coatings used for liquid crystal display panels, color filter-protecting films. SOLUTION: This resin composition is prepared by using a monofunctional unsaturated group-containing aromatic compound having a biphenyl skeleton and, if necessary, monofunctional group-containing aromatic compounds having other structures to synthesize the copolymer simultaneously having hydroxyl groups and carboxy groups in the structure, and then compounding the copolymer with a melamine or guanamine compound and a diluent.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thermosetting resin which is composed of a copolymer having a hydroxyl group and a carboxyl group in its structure, a melamine-based or guanamine-based compound, and a diluent and is excellent in storage stability. The present invention relates to a composition, and further, a cured product thereof has a high refractive index, heat resistance,
The present invention relates to a novel resin composition mainly suitable for a clear coating agent such as a liquid crystal display panel, a color filter protective film and the like because of its excellent adhesion, hardness, solvent resistance and transparency, and a cured product thereof.

[0002]

2. Description of the Related Art In recent years, a plastic material having a high refractive index has remarkably advanced to optical articles, and a liquid crystal display panel, a color filter, a spectacle lens, a Fresnel lens, a lenticular lens, a prism lens sheet for TFT, an aspherical surface. Studies on lenses, optical disks, optical fibers, optical waveguides, etc. are being actively conducted. Among them,
Clear coating of liquid crystal display panel,
For the purpose of smoothing the level difference of the color filter and protecting the color filter from chemical treatment and heating in the subsequent process, a resin having a high refractive index diluted with a solvent as necessary is coated by a spin coating method or the like. Alternatively, it is applied as a protective film. As the coating film or protective film having such a high refractive index, acrylic resin, urethane resin, or epoxy resin is currently used.

[0003]

The acrylic resin or urethane resin is restricted in the processing step after film formation due to its low heat resistance and poor chemical resistance.
Further, when the substrate to be applied is glass, there is a drawback that the adhesion is poor. Further, the epoxy resin has a certain degree of heat resistance, but it is not sufficient in terms of performance such that cracks may occur when the film thickness increases and that it may become colored when heated in the drying and curing steps.

[0004]

Means for Solving the Problems As a result of intensive research to solve the above problems, the present inventor has synthesized a copolymer having a specific structure having a hydroxyl group and a carboxyl group in the structure. By using a resin composition composed of the obtained copolymer, a melamine-based or guanamine-based compound, and a diluent, it is possible to obtain a cured film having excellent heat resistance, adhesion, hardness, and solvent resistance. The present invention has been accomplished by finding a resin composition having a refractive index. That is, the present invention relates to [1] Formula (1)

[0005]

[Chemical 2]

(Wherein R represents a hydrogen atom or a methyl group, and n represents an integer of 1 to 4), the monofunctional unsaturated group-containing aromatic compound (a), the monofunctional unsaturated group It contains a copolymer (A) of a saturated group-containing hydroxy compound (b) and a monofunctional unsaturated group-containing carboxylic acid compound (c), a melamine-based or guanamine-based compound (B) and a diluent (C). Characteristic resin composition, [2] Monofunctional unsaturated group-containing aromatic compound (a) represented by formula (1) described in [1], and monofunctional unsaturated having a structure other than that Copolymer (A ') of group-containing aromatic compound (a'), monofunctional unsaturated group-containing hydroxy compound (b) and monofunctional unsaturated group-containing carboxylic acid compound (c), melamine-based or guanamine-based Characterized by containing a compound (B) and a diluent (C) [1] or [2], wherein the resin composition, [3] copolymer (A) or copolymer (A ′) component has a refractive index at 25 ° C. of 1.50 or more. The resin composition described in [4], wherein the content of the melamine-based or guanamine-based compound (B) component is the copolymer (A)
Or 1 to 100 parts by weight of the copolymer (A ') component
50 parts by weight [1] to [3]
[5] The resin composition according to any one of [1] to [4], wherein [5] is an optical article. 1] to a cured product of the resin composition according to any one of [5].

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The resin composition obtained in the present invention comprises a copolymer (A) or a copolymer (A '), a melamine-based or guanamine-based compound (B) and a diluent (C). To be done. The copolymer (A) used in the present invention includes the monofunctional unsaturated group-containing aromatic compound (a) and the monofunctional unsaturated group-containing hydroxy compound (b) represented by the formula (1). And a monofunctional unsaturated group-containing carboxylic acid compound (c). Specific examples of the monofunctional unsaturated group-containing aromatic compound (a) represented by the formula (1) used here include:
For example, p-phenylphenyloxyethyl (meth) acrylate, p-phenylphenyloxyethyloxyethyl (meth) acrylate, p-phenylphenyloxyethyloxyethyloxyethyloxyethyl (meth) acrylate, o-phenylphenyloxyethyl ( Examples thereof include (meth) acrylate, o-phenylphenyloxyethyloxyethyl (meth) acrylate, and o-phenylphenyloxyethyloxyethyloxyethyloxyethyl (meth) acrylate.
The monofunctional unsaturated group-containing aromatic compound (a) represented by the formula (1) used here may be used alone, but if necessary, such as adjusting the refractive index. Alternatively, two or more kinds of monofunctional unsaturated group-containing aromatic compounds (a) may be mixed and used at an arbitrary ratio.

The copolymer (A ') used in the present invention is a monofunctional unsaturated group-containing aromatic compound (a) represented by the above formula (1) and a monomer having a structure other than that. It can be obtained by copolymerizing a functional unsaturated group-containing aromatic compound (a '), a monofunctional unsaturated group-containing hydroxy compound (b) and a monofunctional unsaturated group-containing carboxylic acid compound (c). . Specific examples of the monofunctional unsaturated group-containing aromatic compound (a ′) having a structure other than the monofunctional unsaturated group-containing aromatic compound (a) represented by the formula (1) used here As, for example, benzyl (meth) acrylate, phenyloxyethyl (meth)
Acrylate, p-methylphenyloxyethyl (meth) acrylate, monofunctional (meth) acrylate compounds such as (meth) acrylate compounds of ethoxylated nonylphenol, styrene, chlorostyrene, 1-vinylnaphthalene, 2-vinylnaphthalene, N-vinyl. Vinyl compounds such as pyrrolidone, allylbenzene, allylphenyl ether, 4-allylanisole, 4-allyl-1,2-
Examples thereof include allyl compounds such as dimethoxybenzene and 4-allyl-2-methoxyphenyl acetate. The monofunctional unsaturated group-containing aromatic compound (a ′) used here may be used alone, but two or more types of monofunctional compounds may be used as necessary, such as adjusting the refractive index. The unsaturated group-containing aromatic compound (a ′) may be mixed and used at an arbitrary ratio. Further, the use ratio of the monofunctional unsaturated group-containing aromatic compound (a) represented by the formula (1) and the monofunctional unsaturated group-containing aromatic compound (a ′) having a structure other than that is Monofunctional unsaturated group-containing aromatic compound (a) represented by the above formula (1) in weight ratio: other than the monofunctional unsaturated group-containing aromatic compound (a) represented by the above formula (1) Monofunctional unsaturated group-containing aromatic compound (a ′) having a structure
= 99: 1 to 1:99 are preferable, and 9 is more preferable.
It is 0:10 to 20:80.

Specific examples of the monofunctional unsaturated group-containing hydroxy compound (b) used in the present invention include 2-hydroxyethyl (meth) acrylate and 2-hydroxyethyl (meth) acrylate.
Examples include hydroxypropyl (meth) acrylate, 1,4-butanediol mono (meth) acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, ethylene glycol monoallyl ether. You can The monofunctional unsaturated group-containing hydroxy compound (b) used here may be used alone, but if necessary, two or more types of monofunctional unsaturated group-containing hydroxy compound (b) may be used. May be mixed and used at an arbitrary ratio.

Specific examples of the monofunctional unsaturated group-containing carboxylic acid compound (c) used in the present invention include, for example, acrylic acid, methacrylic acid, perfluoromethacrylic acid, crotonic acid, itaconic acid, maleic acid, Examples thereof include a reaction product of succinic anhydride and 2-hydroxyethyl (meth) acrylate, and a reaction product of phthalic anhydride and 2-hydroxyethyl (meth) acrylate. The monofunctional unsaturated group-containing carboxylic acid compound (c) used here may be used alone, but if necessary, two or more monofunctional unsaturated group-containing carboxylic acid compounds ( You may mix and use c) in arbitrary ratios.

A monofunctional unsaturated group-containing aromatic compound (a) represented by the above formula (1), a monofunctional unsaturated group-containing hydroxy compound (b) and a monofunctional unsaturated group-containing carboxylic acid compound ( The copolymer (A) of c) is a component (a),
It can be obtained by copolymerizing the component (b) and the component (c). Further, the monofunctional unsaturated group-containing aromatic compound (a) represented by the formula (1), the monofunctional unsaturated group-containing aromatic compound (a ′) having a structure other than that, and the monofunctional The copolymer (A ') of the unsaturated group-containing hydroxy compound (b) and the monofunctional unsaturated group-containing carboxylic acid compound (c) is a component (a), a component (a'), a component (b) and ( It can be obtained by copolymerizing the component c). The proportions of the components (a) or the mixture of the components (a) and (a ') and the ratios of the components (b) and (c) are as follows: (a) or the mixture of the components (a) and (a') , (A) component or (a) component and (a ')
It is preferred to use 50 to 90% by weight, based on the total weight of the mixture of components, component (b) and component (c). Also,
The ratio of the component (b) and the component (c) used is preferably (b) component: (c) component = 10: 1 to 1: 1 in weight ratio. In the case of copolymerizing the component (a) or the mixture of the component (a) and the component (a '), the component (b) and the component (c), a polymerization initiator is used. Specific examples of the polymerization initiator used here include azobisisobutyronitrile, t-butylperoctoate, di-t-butylperoxide peroxide benzoylmethylethylketone peroxide, and the like. Further, it is preferable to use a solvent such as methyl ethyl ketone, ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, butyl cellosolve or solvent naphtha as a diluent during the reaction. The amount of the polymerization initiator used is preferably 0.01 to 5% by weight with respect to the reaction raw material mixture. The reaction temperature is preferably 50 to 100 ° C, particularly preferably 60 to 90 ° C. The reaction time is preferably 1 to 60 hours, particularly preferably 3 to 20 hours. The acid value of the copolymer is preferably 10 to 50 (mgKOH / g), and the hydroxyl value is preferably 10 to 120 (mgKOH / g). Moreover, a preferable molecular weight is 1,000 to 100,000 in terms of average molecular weight.
0, particularly preferably 2000 to 100,000. The refractive index of the copolymer is preferably 1.50 or more at 25 ° C.

In the present invention, a melamine or guanamine compound (B) is used. Specific examples of the melamine-based or guanamine-based compound (B) include, for example, hexamethylolmelamine, hexabutyrolmelamine, partially methylolated melamine and alkylated products thereof, tetramethylolbenzoguanamine, partially methylolated benzoguanamine and alkylated products thereof, and the like. Can be mentioned. These melamine-based or guanamine-based compounds (B)
The amount of the component added is preferably 1 to 50 parts by weight, and particularly preferably 5 to 20 parts by weight, based on 100 parts by weight of the copolymer (A) component or the copolymer (A ') component.

Specific examples of the diluent (C) include, for example,
Glycol ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether,
Ethylene glycol alkyl ether acetates such as methyl cellosolve acetate and ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether, diethylene glycol alkyl ethers such as diethylene glycol diethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether Propylene glycol alkyl ether acetates such as ether acetate, propylene glycol monomethyl ether, propylene glycol dimethyl ether, propylene glycol monoethyl ether, propylene glycol alkyl ethers such as propylene glycol diethyl ether, toluene, Aromatic hydrocarbons such as len and cumene, ketones such as methyl ethyl ketone, cyclohexanone, 2-heptanone and methyl isobutyl ketone, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate and 3-methyl-3-methoxybutylacetate. And the like can be used. You may use these solvent individually or in mixture of 2 or more. Further, if necessary, benzyl ethyl ether, dihexyl ether, isophorone, caproic acid, caprylic acid, 1
It is also possible to use a high-boiling solvent such as -octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, propyl carbonate, phenylcellosolve acetate, carbitol acetate. . These diluents (C) are used in an amount of 100 to 2 per 100 parts by weight of the total amount of the copolymer (A) component or the copolymer (A ′) component and the melamine-based or guanamine-based compound (B) component.
It is preferably used within the range of 000 parts by weight.

In the resin composition of the present invention, the copolymer (A) or the copolymer (A '), the melamine-based or guanamine-based compound (B) and the diluent (C) component are heated, dissolved, rooted, It can be prepared by dispersing or the like.

The resin composition of the present invention further includes fillers, color pigments, leveling agents, defoaming agents, antioxidants, silane coupling agents, epoxy resins (eg bisphenol type epoxy resin, novolac type epoxy resin, etc.). )
Etc. can be mixed.

Next, the method of using the resin composition obtained in the present invention will be described with reference to an example of a protective film for a color filter used in a liquid crystal color display or the like. A photosensitive composition made of a natural polymer such as gelatin or glue or a synthetic polymer such as an acrylic resin is coated on a substrate such as glass or a solid-state image sensor in advance by a coating method such as spin coating to form a coating film. After patterning, the resin composition of the present invention is applied on a color filter formed by dyeing by a coating method such as spin coating,
The solvent can be dried at room temperature to 150 ° C. and then cured at 200 ° C. for 1 hour to obtain a color filter having a protective film (cured film). The cured film obtained from the resin composition of the present invention is particularly suitable as a protective film for a color filter used in a liquid crystal color display or the like, but as other applications, a liquid crystal display panel or the like, other optical articles, It can also be used for paints, clear coatings other than optical articles, resists and the like.

[0017]

EXAMPLES The present invention will be specifically described below with reference to examples. The present invention is not limited to the following examples.

Synthesis Example of Copolymer (A) Example 1: 100.0 g of propylene glycol monomethyl ether acetate was charged into a 300 ml four-necked flask, the temperature was raised to 70 ° C., and then o-phenylphenyloxyethyl acrylate ( Product Name: KAYARAD O
PP-1, manufactured by Nippon Kayaku Co., Ltd., 70.0 g, 2-hydroxyethyl methacrylate 25.0 g, acrylic acid 5.
A mixed solution of 0 g and 2 g of azobisisobutyronitrile was added dropwise over 3 hours. 70-8 after dropping
The mixture was kept at 0 ° C for 1 hour, then charged with 1 g of azobisisobutyronitrile, heated and kept at 80 to 90 ° C for 10 hours.
The reaction was carried out over time. After the reaction, the mixture was cooled and filtered to obtain a colorless to pale yellow transparent copolymer (A-1) reaction solution. The viscosity of the obtained copolymer (A-1) reaction liquid is 25 ° C.
Is 1800 mPa · s and the acid value is 19.9 mg KO
H / g and the hydroxyl value was 53.4 mgKOH / g. In addition, 25 of the obtained copolymer (A-1) reaction liquid
The refractive index at 1.degree. C. was 1.4851, the resin solid content was 50.0% by weight, and the refractive index at 25.degree. C. of propylene glycol monomethyl ether acetate was 1.4001. (A-
The refractive index at 25 ° C. of the resin component of 1) is estimated to be 1.5701.

Synthesis Example of Copolymer (A ') Example 2: 100.0 g of propylene glycol monomethyl ether acetate was charged into a 300 ml four-necked flask, the temperature was raised to 70 ° C., and o-phenylphenyloxyethyl acrylate was then added. 25.0 g, phenyloxyethyl acrylate (trade name: Biscoat # 192, manufactured by Osaka Organic Chemical Industry Co., Ltd.) 50.0 g, 2-hydroxyethyl methacrylate 20.0 g, acrylic acid 5.0 g and azobisisobutyronitrile A mixed solution of 2 g was added dropwise over 3 hours. After completion of dropping, hold at 70 to 80 ° C. for 1 hour, then 1 g of azobisisobutyronitrile
Was charged, the temperature was raised, and the reaction was carried out as it is at 80 to 90 ° C. for 6 hours. Colorless ~ by cooling after reaction and filtering
A slightly yellow transparent copolymer (A'-1) reaction solution was obtained. The viscosity of the obtained copolymer (A′-1) reaction solution was 24 at 25 ° C.
It has an acid value of 19.7 mgKOH / g.
And the hydroxyl value was 42.5 mg KOH / g.
The refractive index of the obtained copolymer (A′-1) reaction liquid at 25 ° C. was 1.4756, and the resin solid content was 5
It was 0.3% by weight, and the refractive index of propylene glycol monomethyl ether acetate at 25 ° C was 1.4001. Therefore, the obtained copolymer (A'-
The refractive index at 25 ° C. of the resin component of 1) is estimated to be 1.5502.

Examples of Resin Composition and Preparation of Cured Film Examples 3 to 6 and Comparative Examples 1 to 3 Compositions shown in Tables 1 and 2 (numerical values indicate parts by weight)
A resin composition was prepared according to the above, and the obtained resin composition was applied onto a glass plate by spin coating to a film thickness of 1 to 3 μm. The obtained coating film was dried at 100 ° C. for 15 minutes, then heated at 150 ° C. for 15 minutes and at 200 ° C. for 1 hour to be thermally cured to obtain a cured film. Performance evaluation was performed on each of the obtained cured films. The results are also shown in Tables 1 and 2.

[0021] Table 1                                                Example                                         3 4 5 6 Copolymer (A-1) 200 200 Copolymer (A'-1) 200 200 EPPN-201 * 1 Nikarac MX-45 * 2 10 10 Nikarac BX-4000 * 3 10 10 Phenol novolac (Softening point 83 ° C) Propylene glycol 390 390 390 390 Monoethyl ether acetate 2-methylimidazole Heat resistance (color difference value) * 4 0.51 0.53 0.42 0.44 Adhesion * 5 ○ ○ ○ ○ Pencil hardness * 6 4H 5H 5H 6H Solvent resistance * 7 ○ ○ ○ ○ Transparency * 8 ○ ○ ○ ○ Storage stability * 9 ○ ○ ○ ○

[0022] Table 2                                                 Comparative example                                         1 2 3 Copolymer (A-1) 200 Copolymer (A'-1) 200 EPPN-201 * 1 100 Nikarac MX-45 * 2 Nikarac BX-4000 * 3 Phenol novolac 65 (Softening point 83 ° C) Propylene glycol Monoethyl ether acetate 400 400 664 2-methylimidazole 1 Heat resistance (color difference value) * 4 0.35 0.30 3.00 Adhesion * 5 ○ ○ ○ Pencil hardness * 6 H 2H 6H Solvent resistance * 7 × × ○ Transparency * 8 ○ ○ ○ Storage stability * 9 ○ ○ ×

Note) * 1 EPPN-201: phenol novolac type epoxy resin manufactured by Nippon Kayaku Co., Ltd. * 2 Nikarac MX-45: manufactured by Sanwa Chemical Co., Ltd.
Methyl and n-butyl mixed etherified melamine resin. * 3 Nikalac BX-4000: Methyl and n-butyl mixed etherified benzoguanamine resin manufactured by Sanwa Chemical Co., Ltd. * 4 Heat resistance (color difference value): A test piece was heated at 200 ° C. for 15 minutes, and the degree of coloring before and after heating was measured with a color difference meter (model: Macbeth CE-3000, manufactured by Kormogen). The smaller the number, the less discoloration. * 5 Adhesion: In accordance with JIS K5400, 100 1 mm grids were made on a test piece, and a peeling test was performed using Cellotape (R). After the test, the peeled state of the cross-cut was observed and evaluated according to the following criteria. ◯: 100/100, and peeling does not occur at all. X ... 0/100 to 99/100. * 6 Pencil hardness: Evaluated according to JIS K5400. * 7 Solvent resistance: The surface of the coating film was observed by rubbing the coating film surface 50 times with gauze soaked with methyl ethyl ketone. ○: There is no change on the coating surface. X: The coating film surface is dissolved. * 8 Transparency: The cured film was visually observed. ○: There is no opaque part such as whitening or cloudiness in the cured film. X: Whitening and turbidity are observed in the cured film. * 9 Storage stability: After allowing the resin composition prepared according to the composition shown in Table 1 and Table 2 to stand at 40 ° C. for 1 month,
The state of the resin composition was observed. ○: There is no change. X ... Viscosity increased and gel was generated.

[0024]

As is clear from Examples 3 to 6, Comparative Examples 1 to 3 and Tables 1 and 2, the resin composition of the present invention has excellent storage stability, and the cured product thereof has heat resistance, adhesiveness, Since it has excellent hardness, solvent resistance and transparency, it is useful as a clear coating agent for optical articles, mainly liquid crystal display panels, color filter protective films and the like.

Continued front page    F term (reference) 4J002 BG041 BG051 BG071 EA037                       EC017 EC047 ED017 ED027                       ED037 EE027 EE057 EH007                       EJ037 EU186 GP00 GP03                 4J027 AA02 AB01 AB02 AJ02 BA02                       BA04 BA06 BA07 BA08 CA25                       CB03 CD04 CD05 CD08 CD10                 4J038 CG141 CH081 CH141 GA03                       GA06 JB36 KA06                 4J100 AB00S AB01S AB02S AB08S                       AE09Q AE09S AJ02R AJ03R                       AJ08R AJ09R AL08P AL08Q                       AL09S AL11S BA03Q BA04Q                       BA05S BA08P BB07R BC43Q                       BC43S BC44P CA03 CA05                       CA06 DA61 DA62 JA32 JA39

Claims (6)

[Claims] 1. A formula (1): (Wherein R is a hydrogen atom or a methyl group, and n is 1
Represents an integer of 4; ) A copolymer of a monofunctional unsaturated group-containing aromatic compound (a), a monofunctional unsaturated group-containing hydroxy compound (b) and a monofunctional unsaturated group-containing carboxylic acid compound (c) ( A), a resin composition comprising a melamine-based or guanamine-based compound (B) and a diluent (C). 2. A monofunctional unsaturated group-containing aromatic compound (a) represented by the formula (1) according to claim 1 and a monofunctional unsaturated group-containing aromatic compound having a structure other than that. (A ′), a copolymer of a monofunctional unsaturated group-containing hydroxy compound (b) and a monofunctional unsaturated group-containing carboxylic acid compound (c) (A ′), a melamine-based or guanamine-based compound (B) and A resin composition comprising a diluent (C). 3. The resin according to claim 1, wherein the copolymer (A) or the copolymer (A ′) component has a refractive index at 25 ° C. of 1.50 or more. Composition. 4. The content of the melamine-based or guanamine-based compound (B) component is 1 to 50 parts by weight with respect to 100 parts by weight of the copolymer (A) or the copolymer (A ') component. The resin composition according to any one of claims 1 to 3. 5. The resin composition according to any one of claims 1 to 4, which is used as an optical article. 6. A cured product of the resin composition according to claim 1.