JPH1017629A - Hard-coating resin composition and method for curing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition which can give hard coats having high surface hardness and good surface dryability and shrinkage and a method for curing the same. SOLUTION: A hard-coating resin composition comprising an unsaturated alkyl resin composition and/or an unsaturated epoxy ester resin composition, at least one polyfunctional (meth)acrylate, a cure accelerator being an organic slat of cobalt, a cure accelerator being a β-diketone and a curing agent being cyclohexanone peroxide is prepared and then cured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for hard-coating the surface of FRP (fiber reinforced plastic), artificial marble, resin concrete and the like, a method for curing these, and cured products thereof.

[0002]

2. Description of the Related Art The characteristics that greatly affect the product value of various FRP products and polyester artificial marble include basic characteristics such as boiling water resistance, surface hardness, weather resistance, and the like, color, gloss, and transparency of the product surface (the surface to be used). Appearance characteristics such as properties. Various FRP products and artificial marble made of polyester are made of unsaturated polyester resin or vinyl ester resin as matrix matrix, glass mats, chopped strands, glass fiber such as milled fiber as reinforcing material, and calcium carbonate as filler. First, a resin composition is prepared using an inorganic filler such as aluminum hydroxide, glass powder, or the like, and then molded to produce a resin composition. Various molding methods such as hand lay-up molding, spray-up molding, and casting (casting) molding are used. In order to improve surface characteristics and appearance,
If necessary, an FRP or the like is formed after a hard coat resin is applied to a mold in advance.

[0003] Hard coat resins used for such purposes include those obtained by adding pigments, thixotropic agents, inorganic fillers, air barrier agents, etc. to thermosetting resins such as unsaturated polyester resins and bisphenol resins. is there. In the hard coat molding method, a method in which a gel coat resin is usually applied to a mold by a spray-up method, a thermosetting resin is placed, and then curing and drying at room temperature is performed. Done.

[0004]

The basic physical properties and appearance characteristics of the product surface (the surface to be used), which greatly influences the product value of FRP products and polyester artificial marble, are as described above, 1) surface hardness, 2) resistance. Boiling water, 3) weather resistance, 4)
In terms of gloss and workability, 5) sprayability, etc. Among them, the characteristics excluding 1) can be improved by improving the resin and the curing system to obtain excellent products. Is coming. However, as for 1), as long as an unsaturated polyester resin, a vinyl ester resin, or the like is used as the matrix resin, a product having a high surface hardness could not be obtained because the inherent hardness of these resins is low. Therefore, various improvements have been made in order to obtain a product having a high surface hardness, such as modification of a matrix resin and molding with a new resin. As one method, a method of obtaining a product having a high surface hardness using an acrylic resin, particularly a polyfunctional (meth) acrylate, has been attempted. As a method of using the polyfunctional (meth) acrylate, there are a method of using as a matrix resin (JP-A-61-69855) and a method of using as a gel coat resin. In the former method, a product having a high surface hardness is obtained. For this purpose, it is necessary to use a matrix resin composition having an increased polyfunctional (meth) acrylate content, which is disadvantageous in terms of cost. Also in the latter method, in the case of an acrylic resin, in the case of a thin film forming method by thermal curing using a radical polymerization initiator or the like, it is difficult to cure the surface due to the action of inhibiting polymerization of air, and large shrinkage during polymerization. Due to the rate, cracks and peeling occur, and it is difficult to cure the coating film. In addition, curing by ultraviolet irradiation or electron beam irradiation using a photopolymerization initiator is difficult to cure in a complicated shape or a thick film. In addition, in a curing method using a radical initiator, use of a resin composition in which an unsaturated polyester resin or a vinyl ester resin and a polyfunctional (meth) acrylate are blended has been studied in order to improve surface drying property and shrinkage. However, although the surface drying property and shrinkage ratio are improved, the surface hardness is conversely reduced and only a coating film having insufficient hardness is obtained. In the case of a hard coat composition that gives a high crosslink density that expresses high hardness, foaming polymerization due to a sudden reaction occurs when the coating film becomes thick during spraying or when trying to make a thick film (the coating film becomes tattered like popcorn) ) Occurs or cracks occur, making production difficult.

The present inventors have studied to obtain FRP products and the like which can be cured at room temperature and have a high surface hardness. As a result, unsaturated alkyds and / or unsaturated epoxy esters and one or more polyfunctional (meth) acrylates have been obtained. A hard coat molded product with high surface hardness and good surface dryness when using a resin mixture consisting of a resin component consisting of acetoacetate peroxide as a curing agent and organic acid salts of cobalt as a curing accelerator Was found to be obtained (JP-A-1-90210). Further, by adding α-methylstyrene to this system, which is a drawback of this compound, which causes foaming polymerization at a thick film thickness, a hard coat molded product satisfying the conditions such as curing speed and surface hardness can be obtained. (Japanese Patent Laid-Open No. Hei 3-
115414). Another disadvantage of this formulation is silicon dioxide (for example, Aerosil 200: manufactured by Nippon Aerosil Co., Ltd.), aluminum stearate, organically treated clay, methylcellulose, hydroxyethylcellulose, poval, hydrogenated, which are commonly used thixotropic agents. The disadvantage that castor oil, smectite, and the like cannot provide sufficient thixotropic properties can also be solved by using siliconized silicon dioxide (Japanese Patent Application No. 7-34).
9574). However, acetoacetate peroxide used as a curing agent has poor storage stability, and there has been a demand for the development of a method for providing a hard coat molded article having good surface drying properties and high surface hardness without using the acetoacetate peroxide.

[0006]

DISCLOSURE OF THE INVENTION The present inventors have conducted intensive studies to solve the above problems, and as a result, have found that a hard coat containing an unsaturated alkyd and / or unsaturated epoxy ester resin and a polyfunctional (meth) acrylate. In curing the resin mixture for use, it is found that by using a specific curing agent, a curing accelerator and a curing accelerator, a hard coat molded product having a high surface hardness and a good surface drying property can be obtained. Reached.

That is, the present invention relates to (1) an unsaturated alkyd resin and / or an unsaturated epoxy ester resin, a polyfunctional (meth) acrylate, an organic acid salt of cobalt as a curing accelerator, and β as a curing accelerator. -A resin composition for hard coat comprising a diketone and cyclohexanone peroxide as a curing agent. (2) A cured product obtained by curing the resin composition for hard coat according to (1). (3) An unsaturated alkyd resin and / or an unsaturated epoxy ester resin and a mixture of organic acid salts of cobalt as a curing accelerator, β-diketone as a curing accelerator and cyclohexanone peroxide as a curing agent. The present invention relates to a method for curing a resin mixture for a hard coat containing a functional (meth) acrylate.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The unsaturated alkyd resin used in the present invention is a resin which always contains an unsaturated dibasic acid as one component, and is obtained by subjecting a glycol to heat-dehydration condensation reaction with a saturated dibasic acid if necessary. The charging ratio is approximately the equivalent ratio of the acid and the glycol, but the ratio of the unsaturated dibasic acid to the saturated dibasic acid can be arbitrarily selected. The preferred ratio of the unsaturated dibasic acid to the saturated dibasic acid is 1: 0.2 to 3 in molar ratio. Specific examples of the unsaturated dibasic acid that can be used include maleic anhydride, fumaric acid, itaconic acid, citraconic acid, and the like.Also, as the saturated dibasic acid, phthalic anhydride,
Examples thereof include isophthalic acid, terephthalic acid, adipic acid, sebacic acid, tetrachlorophthalic anhydride, hetic acid, azelaic acid, succinic acid, tetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, and hexahydrophthalic anhydride. Specific examples of glycols that can be used include ethylene glycol, propylene glycol, butanediol, diethylene glycol, dipropylene glycol, triethylene glycol, pentanediol, hexanediol, neopentyl glycol, 2,2,4-trimethylpentane -1,3-diol, hydrogenated bisphenol A and the like.

In the present invention, the term "unsaturated epoxy ester resin" means a polyepoxide and an .alpha.,. Beta.-unsaturated monobasic acid which are used in substantially equivalent amounts.
It is obtained by reacting for 10 to 10 hours. Specific examples of polyepoxides that can be used include bisphenol A,
Saturation of glycidyl ether of polyhydric phenols such as bisphenol F, tetrabromobisphenol A, tetraphenolethane, phenol novolac, glycidyl ether of polyhydric alcohols such as polypropylene glycol, hydrogenated bisphenol A, hexahydrophthalic anhydride, dimer acid, etc. Glycidyl esters of acids, unsaturated acids,
Examples include glycidylamine such as diaminodiphenylmethane, isocyanuric acid, and hydantoin, epoxidized fatty acid or epoxidized dry oil fatty acid, epoxidized diolefin, and epoxidized polyester. Further, specific examples of the α, β-unsaturated monobasic acid that can be used include methacrylic acid, acrylic acid, crotonic acid and the like.

Specific examples of the polyfunctional (meth) acrylate used in the present invention include an ester compound obtained by reacting a polyfunctional alcohol and (meth) acrylic acid, and a reaction between a bisphenol A derivative and (meth) acrylic acid. Examples thereof include ester compounds and the like, and specific examples thereof include compounds represented by the following (a) to (f).

[0011]

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(In the formula (a), n ₁ is 0 or an integer of 1 to 4, and at least two of a plurality of X ₁ are (meth) acryloyloxy groups and the rest are hydroxyl groups or methyl groups.)

Two or more (meth) molecules in one molecule represented by
Mono- or polypentaerythritol poly (meth) acrylate having an acryloyloxy group,

[0014]

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(In the formula (b), R ₁ represents —CH ₂ —, —C
(CH ₃ ) ₂ — is a hydrocarbon group selected from —, n ₂ is 0 or an integer of 1 to 5, X ₂ is a (meth) acryloyloxy group, and Y ₁ is an alkylene having 6 or less carbon atoms. Group. Y ₁ is the same or different when n ₂ is 2 or more. )

A compound represented by the formula:

A (meth) acrylic urethane resin obtained by reacting a residual hydroxyl group of the (meth) acrylated ester derivative represented by the formula (a) and / or (b) with a diisocyanate compound;

[0018]

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(In the formula (d), n ₃ is 0 or an integer of 1 to 5; X ₃ is a (meth) acryloyloxy group;
₂ is an alkylene group having 6 or less carbon atoms. )

A compound represented by the formula:

[0021]

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(In the formula (e), n ₄ is 0 or an integer of 1 to 5, X ₄ is a (meth) acryloyloxy group,
₃ is an alkylene group having 6 or less carbon atoms, at least one R ₂ is a (meth) acryloyloxy group, and the rest is hydrogen or an alkyl group having up to 2 carbon atoms. )

A compound represented by the formula:

[0024]

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(In the formula (f), R ₃ and R ₄ are hydrogen or a methyl group, R ₅ is a (meth) acryloyloxy group, and n ₅ is an integer of ₃ to 23.)

A compound represented by the formula:

These polyfunctional (meth) acrylates are
They can be used alone or as a mixture of two or more kinds in an arbitrary ratio. The mixing ratio of the unsaturated alkyd resin and / or the unsaturated epoxy ester resin and the polyfunctional (meth) acrylate can be arbitrarily selected, but is preferably in a weight ratio of (unsaturated alkyd resin and / or unsaturated epoxy ester resin). ) / (Polyfunctional (meth) acrylate) =
10/90 to 90/10.

Specific examples of the organic acid salts of cobalt used as the curing accelerator in the present invention include cobalt naphthenate and cobalt octylate. The amount of addition
6% by weight based on 100 parts by weight of resin component for hard coat
0.05-1 part by weight, preferably 0.1-0.5 parts by weight in terms of cobalt (refers to the content of metallic cobalt in the curing accelerator).
Parts by weight. This is usually used by adding it to the hard coat resin component just before curing, but it can be mixed in advance with the hard coat resin component. In addition to organic acid salts of cobalt, potassium, sodium, iron, copper, zinc,
Organic acid salts such as calcium can be used in combination as a curing accelerator.

Preferred specific examples of the β-diketone used as a curing accelerator in the present invention are those represented by formula (g):

[0030]

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(R ₆ and R ₇ may be the same or different and each represents a C ₁ -C ₁₅ alkyl group, an alkoxy group, an aralkyl group, or a mono- or di-alkyl-substituted amino group; (In (h), R ₈ represents a C ₁ -C ₅ alkylene group.)

[0032]

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Is a compound represented by the formula: In addition, acetylacetone is a β-diketone, but it has a polymerization inhibiting action, so it is preferable to avoid using it.

Specific examples of the curing accelerator which can be used in the present invention include methyl acetoacetate, ethyl acetoacetate,
2- (acetoacetoxy) ethyl methacrylate, methyl pivaloyl acetate, ethyl pivaloyl acetate, diethyl malonate, N-pyrrolidinoacetoacetamide, N-morpholinoacetoacetamide, N, N-dimethylacetoacetamide, N, N-diethylacetoacetamide ,
α-acetyl-γ-butyrolactone and the like. The amount of the curing accelerator used for the hard coat resin is 0.1 to 5 with respect to 100 parts by weight of the hard coat resin component.
Parts by weight, preferably 0.2 to 2 parts by weight. This is mixed with the hard coat resin in advance, but it can be added to the hard coat resin immediately before curing.

The cyclohexanone peroxide used as a curing agent in the present invention is a ketone peroxide usually obtained by reacting cyclohexanone with hydrogen peroxide in the presence of an acid catalyst, and comprises dimethyl phthalate (DM)
P), dioctyl phthalate (DOP), triethyl phosphate (TEP), propylene glycol monoacetate (PMA) or the like may be used by dissolving in a solvent.
It may be used in powder form. Resin component for hard coat 10
The amount of cyclohexanone peroxide used is 0.5 to 5 parts by weight, preferably 0.7 to 3 parts by weight, based on 0 parts by weight. This may be blended in advance with the resin component,
When applied like an external mixing spray, they may be sprayed separately. As a curing agent, a perester such as t-butyl peroxy-2-ethylhexanoate can be used in combination.

The resin composition for hard coat of the present invention can be adjusted to a viscosity suitable for use by adding a styrene monomer, MMA (metamethyl acrylate) and the like. Also, α-methylstyrene can be added to the resin composition for hard coat of the present invention as one component of the monomer.

The resin composition for hard coat of the present invention comprises an unsaturated alkyd resin and / or an unsaturated epoxy ester resin, a polyfunctional (meth) acrylate, a monomer, a curing agent, a curing accelerator and a curing accelerator in the above proportions. It is manufactured by mixing. Further, this includes thixotropic agents, polymerization inhibitors, polymerization accelerators, air barrier agents, inorganic fillers, pigments,
Ordinary additives such as an ultraviolet absorber may be blended.

The cured product obtained by using the resin composition for hard coat of the present invention has basic physical properties and appearance characteristics, high surface hardness, good water resistance to boiling water, excellent weather resistance, and gloss. And sprayability is excellent in terms of workability.

The curing method of the present invention means that 0.05 to 1 part, preferably 0.1 to 0.5 part, of an organic acid salt of cobalt is used as a curing accelerator, and 0.1 parts of β-diketone is used as a curing accelerator. 1 to 5 parts, preferably 0.2 to 5 parts, and 0.5 to 5 parts, preferably 0.7 to 3 parts, of cyclohexanone peroxide as a curing agent are added to and mixed with 100 parts of the resin mixture, and the curing temperature is increased. This is a method of curing at room temperature to 100 ° C. for a curing time of 1 to 48 hours. These include thixotropic agents, polymerization inhibitors, polymerization accelerators, air barriers, inorganic fillers, pigments,
Ordinary additives such as an ultraviolet absorber may be blended.

The cured product of the resin composition for a hard coat of the present invention is prepared by using, for example, the above-mentioned curing accelerator, curing accelerator and cyclohexanone peroxide in an amount within the above-mentioned range, and using an unsaturated alkyd resin and / or an unsaturated alkyd resin. It is added to a hard coat resin mixture containing an epoxy ester resin and a multifunctional (meth) acrylate,
It is manufactured by curing under a temperature condition of ° C. The resin mixture may be blended with the usual additives.

Specific examples of the coating method of the hard coat resin composition of the present invention include a spray method, a brush coating, an electrostatic coating, a dipping method, a flow coater method and an in-mold coating method. Any of these can be selected depending on the purpose. Suitable resins to be coated include
Examples include a resin-con layer and an FRP layer.

[0042]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. Parts used below mean parts by weight unless otherwise specified.

Reference Example 1 For the production of an unsaturated alkyd resin, a stir bar, a condenser, an inert gas inlet tube, and a thermometer were attached to a 1-liter four-necked flask. A flask is charged with 138 parts of ethylene glycol, 98 parts of maleic anhydride, and 148 parts of phthalic anhydride, and heated to 80 to 90 ° C. in an oil bath while slowly flowing nitrogen gas. Stirring is started from this stage, and the temperature is raised to 150 to 160 ° C. over 1 to 1.5 hours, and further increased to 190 ° C. for 3 to 4 hours. After keeping at 190 ° C for 1 hour, replace the condenser with a siphon.
Reduce the pressure to 200 mmHg. A sample is taken occasionally during the depressurization, and the reaction is continued until the acid value becomes 50 or less. When the acid value reaches 50 or less, the temperature is lowered to 100 ° C., and about 0.02 g of hydroquinone is added as a polymerization inhibitor to obtain 340 parts of an unsaturated alkyd resin (A).

Reference Example 2 The production of an unsaturated epoxy ester was carried out using 376 parts of diglycidyl ether of 4,4-isopropylidene diphenol,
172 parts of methacrylic acid, 2 parts of benzyldimethylamine,
0.05 parts of hydroquinone was charged and reacted at 115 ° C. while measuring the acid value to obtain 510 parts of an unsaturated epoxy ester resin (B) having an acid value of 7.6.

REFERENCE EXAMPLE 3 Cyclohexanone peroxide was synthesized by 153 parts of dimethyl phthalate, 49 parts of triethyl phosphate,
3 parts in a mixture of 98 parts of cyclohexanone and 8 parts of 50% sulfuric acid
120 parts of a 60% hydrogen peroxide solution was added dropwise at 40 ° C. over 40 minutes at 5 ° C., followed by a reaction at the same temperature for 1 hour. The waste liquid was separated at room temperature and dehydrated to obtain 370 parts of cyclohexanone peroxide. Its active oxygen content was 8.0%.

Examples 1 to 12 First, each of the resins was mixed in the proportions shown in Table 1 to prepare a mixture 1 to a mixture 1 to be used in the resin composition for hard coat of the present invention.
0 was prepared. Next, the respective chemicals were mixed at a ratio shown in Table 2 to obtain a resin composition for hard coat of the present invention. Next, at 25 ° C., 100 mm × 100 mm
A 1 mm guide is provided, and the hard coat resin composition is flowed over the guide. After the surface is dried, a resin control layer (iso-unsaturated polyester resin (UP) resin:
Inorganic filler = 1: 1, Iso UP resin: Polylite FG
-283, manufactured by Dainippon Ink and Chemicals, Inc., inorganic filler: frit M-27S, manufactured by Nippon Fellow Co., Ltd.
Cast and harden to a thickness of mm. The curing conditions of the back resin layer were 1 part of methyl ethyl ketone peroxide (trade name: Kayamec M, manufactured by Kayaku Akzo Co., Ltd.) and 0.5 parts of 6% cobalt naphthenate. After standing for one day, the pencil hardness of the gel coat surface was measured according to JIS-K-5400. The surface hardness was also measured after curing at 80 ° C. for 2 hours. The surface drying was measured by the touch of a finger, and the time until the stickiness disappeared. The color of the molded product was determined by visual observation. A colorless product was rated as ○, and a slightly colored, practically rated one was rated as △. Table 2 shows the results.

Examples 13 to 15 In place of the back layer of the resin, an FRP layer (iso-based UP resin: glass mat = 7: 3, iso-based UP resin: Polylite FG-283, manufactured by Dainippon Ink and Chemicals, Inc.) , Glass mat: chopped strand mat # 450, manufactured by Nitto Boseki Co., Ltd., size 100 mm × 100 mm) except that a three-ply laminated and cured material was used.
Tests similar to the above were performed, and the results are shown in Table 2.

Table 1 shows the components and the composition ratio of the resin mixture used in the resin composition for hard coat of the present invention, and Table 2 shows the components and the composition ratio and the cured product of the resin composition for hard coat of the present invention. Shows the physical properties of The unit of the numerical value in the composition ratio is part by weight.

[0049]

Table 1 Resin mixture used for the resin composition for hard coat Mixture 1 Mixture 2 Mixture 3 Mixture 4 Mixture 5 Unsaturated alkyd 16 16 30 Unsaturated epoxy ester 19 33 DPHA 28 28 44 17 70 TMPTA 56 56 37 50 St 20 20 20 Mixture 6 Mixture 7 Mixture 8 Mixture 9 Mixture 10 Unsaturated alkyd 30 25 15 25 Unsaturated epoxy ester 30 10 DPHA 58 TMPTA 70 70 58 58 DPCA-30 17 DPCA-20 17 D-310 17

[0050]

[Table 2] [Table 2] Component ratio of resin composition for hard coat and physical properties of cured product Actual use Hard Hard Hard surface Surface hardness Example of molded, cured, dried product Resin Accelerator Time 25 ℃ 80 ℃ Colored No Mixing Progress hardening 2 hours Material assistant 1 2 (hr) After hardening for 1 day 1 Mix 1 Co AAE Cyclo 35H 7H 2 Mix 1 Co AAE Cyclo TBPO 3 5H 9H 3 Mix 2 Co AAEM Cyclo 3 5H 7H ○ 4 Mixture 2 Co DEAAA Cyclo 3 5H 8H △ 5 Mixture 2 Co AAE Cyclo 35H 7H ○ 6 Mixture 3 Co AAE Cyclo 4 4H 6H ○ 7 Mixture 3 Co DEAAA Cyclo 4 4H 8H △ 8 Mixture 3 Co AAM Cyclo 4 4H 8H ○ 9 Mixture 4 Co AAE Cyclo 4 4H 8H ○ 10 Mixture 5 Co AAE Cyclo 35H 9H ○ 11 Mixture 6 Co AAE Cyclo 35H 8H ○ 12 Mixture 7 Co AAE Cyclo 45H 8H ○ 13 Mixture 8 Co AAE Cyclo 4 3H 7H ○ 14 mixture 9 Co AAE cyclo 3 3H 7H ○ 15 mixture 10 Co AAE cyclo 3 4H 8H ○

* The amount of the curing agent 1 is 2 parts with respect to 100 parts of each mixture shown in Table 1, and represents cyclo: cyclohexanone peroxide. * The amount of curing agent 2 added is 0.5 parts per 100 parts of each mixture described in Table 1. * The amount of curing accelerator added is 6% cobalt naphthenate 0.3 parts per 100 parts of each mixture. * The amount of the curing accelerator added is 10% for each mixture listed in Table 1.
1 copy for 0 copy

(Description of Abbreviations) DPHA: Pentaerythritol hexaacrylate (trade name) KAYARAD DPHA (manufactured by Nippon Kayaku Co., Ltd.) TMPTA: trimethylolpropane triacrylate (trade name) KAYARAD TMPTA (manufactured by Nippon Kayaku Co., Ltd.) St: styrene Monomer (Wako Pure Chemical Industries, Ltd.)
DPCA-30: Caprolactone-modified dipentaerythritol hexaacrylate Trade name KAYARAD
DPCA-30 (manufactured by Nippon Kayaku Co., Ltd.) DPCA-20: caprolactone-modified dipentaerythritol hexaacrylate Trade name KAYARAD
DPCA-20 (manufactured by Nippon Kayaku Co., Ltd.) D-310: Alkali-modified dipentaerythritol tetraacrylate Trade name KAYARAD D-31
0 (manufactured by Nippon Kayaku Co., Ltd.) TBPO: t-butylperoxy-2-ethylhexanoate Co: cobalt naphthenate (Co metal content 6%) AAE: ethyl acetoacetate AAM: methyl acetoacetate ABL: α- Acetyl-γ-butyrolactone DEAAAA: diethylacetoacetamide AAEM: 2- (acetoacetoxy) ethyl methacrylate

From the results in this table, it can be seen that when the resin composition for hard coat of the present invention is used, the surface drying time is short, and
Hardness is high at both the curing at 80 ° C. and at 80 ° C., and a good cured product is obtained. In addition, excellent results have been obtained in the degree of coloring of the molded article.

Example 16 0.3 parts of 6% cobalt naphthenate as a curing accelerator, 1 part of AAEM as a curing accelerator and 2 parts of cyclohexanone peroxide as a curing agent were added to 100 parts of the resin of mixture 3 in Table 1 and mixed. did. This was applied on a glass plate in the same manner as in Examples 1 to 12, and a resin layer was also prepared in the same manner. When this is placed at 25 ° C, the surface drying time is 4 hours,
The pencil hardness was 4H after 24 hours at 25 ° C, the pencil hardness was 6H after curing for 2 hours at 80 ° C, and there was no coloring of the cured product.

[0055]

The resin composition for a hard coat of the present invention comprises:
A molded article having a high surface hardness, which was not obtained with a conventional unsaturated polyester resin molded article, and having excellent surface drying properties. By hard-coating with the resin composition for hard coat of the present invention, applications of FRP products and artificial marbles are widened, high added value is expected, and industrial value is great.

Claims (3)

[Claims] 1. An unsaturated alkyd resin and / or an unsaturated epoxy ester resin, a polyfunctional (meth) acrylate,
A resin composition for a hard coat, comprising an organic acid salt of cobalt as a curing accelerator, β-diketone as a curing accelerator, and cyclohexanone peroxide as a curing agent. 2. A cured product obtained by curing the resin composition for hard coat according to claim 1. 3. An organic acid salt of cobalt as a curing accelerator,
Resin mixture for unsaturated hard coat containing unsaturated alkyd resin and / or unsaturated epoxy ester resin, characterized by using β-diketone as curing accelerator and cyclohexanone peroxide as curing agent Curing method.