JP2001139872A - Curable coating composition for coating wood - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curable coating composition for wood which shows excellent curability and gives a coated film showing excellence in adhesion and pencil hardness. SOLUTION: A curable coating composition for wood contains (a) a compound having not less than 2 epoxy groups in a molecule and (b) a (meth)acrylate compound having an alkylene oxide unit in a molecule.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curable resin composition for coating wood, and is awarded in the field of paint and in the field of producing and using wood.

[0002]

2. Description of the Related Art Wood, such as flooring materials, wall materials or furniture, is coated on its surface for the purpose of imparting aesthetics such as durability and gloss. To date, various coating compositions and coating methods for coating wood have been proposed and put into practical use. Conventionally, as a coating composition used for this purpose, lacquer, amino alkyd, urethane, polyester,
Alternatively, various synthetic resin paints such as emulsions are used. However, the conventional coating composition may have insufficient curability or insufficient adhesion and hardness of the coating film. Furthermore, the composition was cured at room temperature (natural drying) or by heating. However, the drying requires a large energy cost, and requires a large-scale equipment and a long curing time. Takes time,
Further, the use of an organic solvent has a problem that a harmful organic solvent is volatilized in a large amount, and the development of a coating composition for wood which cures quickly and has no pollution is strongly desired.

[0003] In order to solve this problem, in recent years, wood coating compositions which are cured by active energy rays such as ultraviolet rays or electron beams have been developed. Most of the conventional active energy ray-curable coating compositions for wood use unsaturated polyesters and (meth) acrylates which are cured by active energy ray-initiated radical polymerization. Those that have been used are widely used because they have a good gloss and a firm feeling and have a beautiful finish.

[0004]

However, the conventional active energy ray-curable coating composition for wood cures instantaneously, but has a large internal strain, so that cracks are easily generated in the coating film. There was a problem that the adhesion to the substrate was poor. As an active energy ray curing technique other than the active energy ray initiated radical polymerization, an active energy ray initiated cationic polymerization technique has been put to practical use. In particular, since the active energy ray-initiated cationic polymerization is not inhibited by oxygen, there is no limitation that the polymerization must be performed in an inert atmosphere, and there is an advantage that rapid and complete polymerization can be performed in air.

[0005] To date, the active energy ray-initiated cationic polymerization technique has been developed using two types of epoxy resins and vinyl ethers.
Focused on the polymerization of different types of monomers. In particular, a photocurable epoxy resin has excellent adhesiveness, and its coating film has good heat resistance and chemical resistance. However, many conventional photocurable epoxy resins have relatively slow photopolymerization rates,
Among these, there are also alicyclic epoxy resins having a relatively high photopolymerization rate.However, in the application of a wood coating composition having a relatively thick coating film, this alicyclic epoxy resin hardens only the surface to the interior. In some cases, it does not cure, and has the disadvantage that the cured coating film is brittle. On the other hand, photocurable vinyl ethers are often volatile and have a strong odor, and also compared to photocurable epoxy resins and alicyclic epoxy resins.
In many cases, the curability is insufficient, the shrinkage during curing is large, and the adhesion is not sufficient. In addition, when used as a wood coating composition, the surface of the coating film may not be glossy or may have insufficient pencil hardness.

Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide a curable coating composition for wood having excellent curability and a coating film having excellent adhesion and pencil hardness. is there.

[0007]

Under these circumstances, the present inventors have conducted intensive studies and as a result, have found that a specific composition can solve the above-mentioned problems as a curable coating composition for wood coating. Thus, the present invention has been completed. That is, the present invention provides the following components (a) and (b): (a) a compound having two or more epoxy groups in one molecule, and (b) a (meth) acrylate having an alkylene oxide unit in one molecule. The present invention provides a curable coating composition for coating wood, characterized by containing a compound.

The present invention further provides a curable coating composition for wood coating, further comprising the following component (c): (c) a compound having 1 to 4 oxetane rings in one molecule. It is.

[0009]

DETAILED DESCRIPTION OF THE INVENTION (a) Used in the present invention
The component is not particularly limited as long as it is a compound having two or more epoxy groups in one molecule, and specifically, diglycidyl ether of ethylene glycol, diglycidyl ether of propylene glycol, and diglycidyl ether of butanediol Diglycidyl ether of pentanediol, diglycidyl ether of hexanediol, diglycidyl ether of diethylene glycol, diglycidyl ether of triethylene glycol, diglycidyl ether of polyethylene glycol, diglycidyl ether of dipropylene glycol, diglycidyl of tripropylene glycol Ethers, diglycidyl ethers of polypropylene glycol, dimethylolethane, or triglycidyl ethers, dimethylolpropane di Is triglycidyl ether, di- or triglycidyl ether of glycerin, tri- or tetraglycidyl ether of pentaerythritol, polyglycidyl ether of sorbitol, diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, polyglycidyl ether of phenol novolak , Polyglycidyl ether of cresol novolak, limonene diepoxy, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, bis (3,4-epoxycyclohexylmethyl) adipate, 3,4-epoxycyclohexylmethyl-3 Adduct of 3,4-epoxycyclohexanecarboxylate with caprolactone, 3,4-epoxycyclohexylmethyl-3,4-epoxy City cyclohexanecarboxylate (methyl) valerolactone adduct, 2- (3,4-epoxycyclohexyl-5,5
Spiro-3,4-epoxy) cyclohexane-metadioxane, bis (3,4-epoxycyclohexyl) adipate, bis (3,4-epoxycyclohexyl) ether, bis (3,4-epoxycyclohexylmethyl)
Ether and the like.

Among these components (a), alicyclic epoxies such as 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate and bis (3,4-epoxycyclohexylmethyl) adipate, and the following formula (A) 1);

[0011]

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The limonene diepoxy represented by the formula (1) is particularly preferred in that it has high curability and excellent adhesion to a substrate.

The component (a) can be used alone or in combination of two or more. Further, a preferable blending ratio of the component (a) is a total amount of the component (a) and the component (b), or when a compound other than the components (a) and (b) shown below is blended, 100 parts by weight (hereinafter referred to as "curable component")
“Parts” means “parts by weight”. ),
The amount is preferably from 10 to 90 parts, more preferably from 20 to 80 parts. If the proportion is less than 10 parts, the adhesion of the cured film of the composition to the substrate is not sufficient, and if it exceeds 90 parts, the flexibility of the coating film is poor and the coating film may be brittle. is there.

The component (b) used in the present invention is not particularly limited as long as it is a (meth) acrylate compound having an alkylene oxide unit in one molecule, and specifically, ethylene oxide or propylene oxide of alcohol An adduct (meth) acrylate compound may be used. Examples of the alcohol include ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, 2-ethylhexanol, phenol, nonylphenol, cumylphenol, ethylene glycol, propylene glycol,
Butanediol, pentanediol, hexanediol, heptanediol, nonanediol, neopentyl glycol, bisphenol A, bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F, trimethylolethane, trimethylolpropane, glycerin,
Examples include pentaerythritol, ditrimethylolpropane, diglycerin, dipentaerythritol and the like. For the addition of the alkylene oxide, ethylene oxide alone, propylene oxide alone, or a mixture of ethylene oxide and propylene oxide can be used.
In addition, (meth) acrylate represents acrylate or methacrylate (the same applies hereinafter).

Among these components (b), (meth) acrylate of ethylene oxide adduct of phenol, (meth) acrylate of propylene oxide adduct of phenol, (meth) acrylate of ethylene oxide adduct of nonylphenol, and (meth) acrylate of nonylphenol A (meth) acrylate of a propylene oxide adduct is a preferred compound from the viewpoint of improving adhesion to a substrate.

Also, (meth) acrylate of ethylene oxide adduct of trimethylolpropane and (meth) acrylate of propylene oxide adduct of trimethylolpropane
Acrylate, (meth) acrylate of glycerin ethylene oxide adduct, (meth) acrylate of glycerin propylene oxide adduct, (meth) acrylate of pentaerythritol ethylene oxide adduct, (meth) acrylate of pentaerythritol propylene oxide adduct Acrylate is a preferred compound from the viewpoint of developing the hardness of the coating film.

The component (b) can be used alone or in combination of two or more. Further, a preferable mixing ratio of the component (b) is 10 to 90 parts with respect to 100 parts of the total amount of the curable component. When the proportion is less than 10 parts, the hardness of the cured coating film is poor, and when it exceeds 90 parts, the adhesion to the substrate is poor.

In the present invention, when a higher curing speed is required, it is preferable to further add the component (c). The component (c) is not particularly limited as long as it is a compound having 1 to 4 oxetane rings in one molecule, and specifically, as a compound having one oxetane ring in one molecule, , The following general formula (2):

[0019]

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And the like. In the formula (2), R ¹ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, a fluoroalkyl group having 1 to 6 carbon atoms, an allyl group, It is an aryl group, a furyl group or a thienyl group. R
² is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, a 1-propenyl group, a 2-propenyl group, a 2-methyl-1-propenyl group, Carbon number 2 such as methyl-2-propenyl group, 1-butenyl group, 2-butenyl group or 3-butenyl group
A group having an aromatic ring such as ~ 6 alkenyl groups, phenyl groups, benzyl groups, fluorobenzyl groups, methoxybenzyl groups or phenoxyethyl groups, ethylcarbonyl groups,
An alkylcarbonyl group having 2 to 6 carbon atoms such as a propylcarbonyl group or a butylcarbonyl group, an alkoxycarbonyl group having 2 to 6 carbon atoms such as an ethoxycarbonyl group, a propoxycarbonyl group or a butoxycarbonyl group, an ethylcarbamoyl group, and propylcarbamoyl And N-alkylcarbamoyl groups having 2 to 6 carbon atoms, such as a butylcarbamoyl group or a pentylcarbamoyl group.

In the component (C), the compound having two oxetane rings in one molecule is represented by the following general formula (3)
And the like.

[0022]

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In the formula (3), R ¹ is the same group as R ¹ in the general formula (2). R ³ represents, for example, a linear or branched alkylene group such as an ethylene group, a propylene group or a butylene group, and poly (ethyleneoxy)
Linear or branched unsaturated hydrocarbon groups such as linear or branched poly (alkyleneoxy) groups such as a group or poly (propyleneoxy) group, propenylene group, methylpropenylene group or butenylene group, carbonyl group, It is an alkylene group containing a carbonyl group, an alkylene group containing a carboxyl group, an alkylene group containing a carbamoyl group, or a polyvalent group selected from the groups represented by the following formulas (4), (5) and (6).

[0024]

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In the formula (4), R ⁴ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, a methoxy group, an ethoxy group, a propoxy group or a butoxy group. An alkoxy group having 1 to 4 carbon atoms such as a halogen atom such as a chlorine atom or a bromine atom,
A nitro group, a cyano group, a mercapto group, a lower alkylcarboxyl group, a carboxyl group, or a carbamoyl group.

[0026]

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In the formula (5), R ⁵ is an oxygen atom, a sulfur atom, a methylene group, NH, SO, SO ₂ , C (C
F ₃ ) ₂ or C (CH ₃ ) ₂ .

[0028]

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In the formula (6), R ⁶ is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group, or an aryl group. n is 0 to 20
It is an integer of 00. R ⁷ is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group;
An aryl group or a group selected from the group represented by the following formula (7).

[0030]

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In the formula (7), R ⁸ is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group and a butyl group, or an aryl group. m is 0 to 100
Is an integer.

Specific examples of the compound having two oxetane rings in one molecule include compounds represented by the following formulas (8) and (9). The compound represented by the formula (8) is a compound in which R ¹ is an ethyl group and R ³ is a carboxyl group in the formula (3). The compound represented by the formula (9) is a compound in which, in the general formula (3), R ¹ is an ethyl group, R ³ is the formula (6), R ⁶ and R ⁷ are methyl groups, and n is 1.

[0033]

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[0034]

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Among the compounds having two oxetane rings in one molecule, preferred examples other than the above-mentioned compounds include compounds represented by the following general formula (10). In the formula (10), R ¹ is the same group as R ¹ in the general formula (2).

[0036]

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In the component (C), examples of the compound having 3 to 4 oxetane rings in one molecule include a compound represented by the following general formula (11).

[0038]

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In the formula (11), R ¹ is the same group as R ¹ in the general formula (2). R ⁹ has, for example, 1 to 1 carbon atoms such as groups represented by the following formulas (12) to (14).
And a branched poly (alkyleneoxy) group such as a group represented by the following formula (15) or a branched polysiloxy group such as a group represented by the following formula (16). In the formula (12), R ¹⁰ is a lower alkyl group such as a methyl group, an ethyl group or a propyl group. Equation (15)
Wherein l is an integer of 1 to 10. In the equation (16), j is 3
Or 4.

[0040]

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[0041]

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[0042]

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[0043]

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[0044]

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Specific examples of the compound having 3 to 4 oxetane rings in one molecule include a compound represented by the following formula (17).

[0046]

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Further, in one molecule other than the above, 1 to 4
Examples of the compound having two oxetane rings include a compound represented by the following formula (18).

[0048]

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In the formula (18), R ⁸ is the same group as in the formula (7). R ¹¹ is an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, a propyl group or a butyl group or a trialkylsilyl group, and r is 1 to 4.

Preferred specific examples of the oxetane compound used in the present invention include compounds represented by the following formulas (19) to (25).

[0051]

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[0052]

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[0053]

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[0054]

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[0055]

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[0056]

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[0057]

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In the above chemical formulas representing the component (c), the groups represented by the same symbol in one molecule may be the same or different. The curable coating composition for wood coating of the present invention (hereinafter, simply referred to as “composition”) includes the above-mentioned components (a), (b) and (c), and other components as necessary. Can be blended. Examples of other components include a compound having a (meth) acryloyl group and a compound having a vinyl ether group in the molecule. The (meth) acryloyl group represents an acryloyl group or a methacryloyl group.

As the compound having a (meth) acryloyl group, various compounds can be used. For example, compounds having one (meth) acryloyl group include (meth) acrylates of ethanol, propanol, butanol, pentanol, hexanol, heptanol, and 2-ethylhexanol. Examples of the compound having two (meth) acryloyl groups include di (meth) acrylates of ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, heptanediol, and nonanediol. Examples of the compound having three (meth) acryloyl groups include pentaerythritol, trimethylolethane, trimethylolpropane, and tri (meth) acrylate of isocyanuric acid. Examples of the compound having four or more (meth) acryloyl groups include: Examples thereof include poly (meth) acrylate of pentaerythritol, ditrimethylolpropane, and dipentaerythritol. In addition, conventionally known acrylic monomers / oligomers such as urethane acrylate having a urethane bond as a main chain, polyester acrylate having an ester bond as a main chain, and epoxy (meth) acrylate obtained by adding acrylic acid to an epoxy compound, and the like are also included.

As the compound having a vinyl ether group, various compounds can be used. For example, examples of the compound having one vinyl ether group include hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, dodecyl vinyl ether, propenyl ether propylene carbonate, and cyclohexyl vinyl ether. Examples of the compound having two or more vinyl ether groups include cyclohexane dimethanol divinyl ether, triethylene glycol divinyl ether, and novolak divinyl ether.

The composition of the present invention can be cured by irradiation with active energy rays such as ultraviolet rays, visible rays or electron beams, or by heating. In the present invention, an active energy ray-curable composition is preferable because it has excellent curability, cures in a short time, and does not require large-scale equipment. In the composition of the present invention, the component (a) and / or the component (c) can be cured by a cationic polymerization initiator such as an acid catalyst. When a polymerization initiator capable of generating an acid upon irradiation with active energy rays (hereinafter referred to as a photocationic polymerization initiator) is used, the composition can exhibit photocurability. For this, generally used cationic photopolymerization initiators represented by the following formulas (26) to (29) can be used. Preferred examples of the cationic photopolymerization initiator include diaryliodonium salts and triarylsulfonium salts.

[0062]

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[0063]

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[0064]

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[0065]

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In the formulas (26) to (29), R ¹² represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or an alkyl group having 1 to 18 carbon atoms.
R ¹³ is a hydrogen atom, a hydroxyalkyl group or a hydroxyalkoxy group, and is preferably a hydroxyethoxy group. M represents a metal, preferably antimony, X represents a halogen atom,
It is preferably a fluorine atom, k represents a valence of a metal,
For example, it is 5 in the case of antimony.

In the above chemical formulas representing the cationic photopolymerization initiator, the groups represented by the same symbol in one molecule may be the same or different.

When the composition is polymerized by heating, the cationic polymerization initiator may be a protonic acid such as sulfuric acid, phosphoric acid, perchloric acid or boron trifluoride, aluminum chloride,
Lewis acids such as titanium tetrachloride and tin tetrachloride are used.

The cationic polymerization initiator is used in combination with the component (a). When the cationic polymerization initiator further contains the component (c) or a compound having a vinyl ether group, the total amount thereof is 1%.
The content is preferably 0.1 to 20 parts with respect to 00 parts, more preferably 0.1 to 10 parts.
If the amount is less than 0.1 part, the curability will be insufficient, while if it exceeds 20 parts, the light transmittance will be poor, uniform curing cannot be performed, and the smoothness of the coating film surface will be poor. May be lost.

When the composition is cured by irradiating it with ultraviolet light or visible light, the following photoradical polymerization, which is generally used, is used in order to sufficiently exhibit the photocurability of the component (b). A sensitizer or sensitizer is used.

Specific examples of preferred photopolymerization initiators include
Examples of acetophenones include 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone (Irgacure 907 manufactured by Ciba Specialty Chemicals) and benzyl dimethyl ketal (Irgacure 651 manufactured by Ciba Specialty Chemicals) ), 1-
Hydroxycyclohexyl phenyl ketone (Irgacure 184 manufactured by Ciba Specialty Chemicals), diethoxyacetophenone (Fast Cure DEAP manufactured by First Chemical), 2-hydroxy-2-methyl-
1-phenylpropan-1-one (Darocur 1173 manufactured by Ciba Specialty Chemicals), 4- (2-
Hydroxyethoxy) phenyl (2-hydroxy-2-
Propyl) ketone (Irgacure 2959, manufactured by Ciba Specialty Chemicals) and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone (Irgacure 369, manufactured by Ciba Specialty Chemicals). . Benzoin ethers include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin isobutyl ether. Benzophenones include benzophenone, o-
Examples thereof include methyl benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4′-methyl-diphenylsulfide, and 2,4,6-trimethylbenzophenone. As the thioxanthone system, 2-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone and 1-chloro-
4-propoxythioxanthone and the like. As acylphosphine oxides, 2,4,6-trimethylbenzoyldiphenylphosphine oxide,
Bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide and the like can be mentioned. Other examples include camphorquinone.

Preferred sensitizers include triethanolamine, methyldiethanolamine, triisopropanolamine, methyl 4-dimethylaminobenzoate,
Examples include ethyl dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 4,4-dimethylaminobenzophenone, and 4,4-diethylaminobenzophenone.

When the composition is cured by a heating source,
It is preferable to blend a thermal polymerization initiator for curing the component (b). Examples of suitable thermal polymerization initiators include azo compounds such as azoisobutyronitrile, ketone peroxides, hydroperoxides, and alkyl peroxides. Various organic peroxides such as oxides, acyl peroxides and peroxyesters, and inorganic peroxides such as ammonium persulfate.

In the case of standing at room temperature or heating at a relatively low temperature of 100 ° C. or less, it is preferable to add a polymerization accelerator together with the above-mentioned thermal polymerization initiator. As a preferable polymerization accelerator, for example, metals such as cobalt, iron and manganese are used. Organic metal salts with naphthenic acid, linoleic acid, acetylacetone and the like, and reducing amines such as dimethyl paratoluidine and ascorbic acid, and other reducing substances.

These polymerization accelerators are used in combination with, for example, a combination of hydroperoxide, ketone peroxide or peroxyester and an organic metal salt, or a combination of acyl peroxide and a reducing amine.

The mixing ratio of the photopolymerization initiator or the thermal polymerization initiator is based on the total amount of the component (b) and the total amount of 100 parts when a radical polymerizable component such as (meth) acrylate is further compounded. It is preferably 0.1 to 15 parts, more preferably 0.5 to 10 parts.
If the amount is less than 0.1 part, the effect of accelerating the initiation of polymerization becomes insufficient. If the amount exceeds 15 parts, the components truly required for the cured film are reduced, and the target properties of the cured film may be deteriorated. .

The composition of the present invention preferably further contains a leveling agent for the purpose of improving the surface smoothness of the coating film. As the leveling agent, a general surfactant can be used. Specific compounds include, for example, Florad FC, which is a nonionic fluorinated alkyl ester.
-430 (Sumitomo 3M), Megafac F-1
77 (manufactured by Dainippon Ink and Chemicals) and Megafac F
And NUC silicone L7002 (manufactured by Nippon Unicar) and FZ-2165 (manufactured by Nippon Unicar) as silicone-based compounds. The compounding ratio of the leveling agent is 0.01 to 100 parts of the total amount of the curable component.
Five parts are preferred.

The composition of the present invention may contain a polymer compound, an inorganic filler, a dye, a pigment, a viscosity modifier, a treating agent, an organic solvent and an ultraviolet ray blocking agent in an amount of up to 100 parts by weight per 100 parts by weight of the curable component. An inert component such as an agent can be blended. As the polymer compound, for example, vinyl ester resin, polyisocyanate compound, polyepoxide, acrylic resin, alkyd resin, urea resin, melamine resin,
Resins such as polyvinyl acetate, vinyl acetate copolymer, polydiene elastomer, saturated polyester and saturated polyether, and various cellulose derivatives such as nitrocellulose and cellulose acetate butylate; linseed oil, tung oil, soybean oil, castor oil And various fats and oils such as epoxidized oil. As inorganic fillers,
Examples thereof include calcium carbonate, talc, mica, clay, silica powder, colloidal silica, asbestos powder, aluminum hydroxide, zinc stearate, zinc white, titanium white, and red iron. Among these inorganic fillers, such as titanium white and red iron,
Some can also be used as pigments. As the organic solvent, alcohols such as methanol, ethanol, butanol and isopropyl alcohol, butyl cellosolve, cellosolve such as methyl cellosolve and ethyl cellosolve,
Examples include methyl cellosolve acetate, cellosolve acetate of ethyl cellosolve acetate and butyl cellosolve acetate, propylene glycol monomethyl ether, toluene, and xylene.

The wavelength of the UV region can be adjusted by adding a photosensitizer in addition to the cationic photopolymerization initiator and / or the photoradical polymerization initiator to the composition of the present invention. Typical photosensitizers that can be used in the present invention include Crivello (JV Crivello, Adv. In Polymer Sc
i., 62, 1 (1984)), specifically, pyrene, perylene, acridine orange, thioxanthone, 2-chlorothioxanthone and benzoflavin.

The viscosity of the composition of the present invention is 500 mP
a · S (25 ° C.) The following is preferred. When the composition of the present invention is used for spray coating, it is preferably at most 300 mPa · S (25 ° C.), more preferably at most 100 mPa · S (25 ° C.).

The method for producing the composition of the present invention is not particularly limited, and the essential component of the present invention, or the essential component and other components, if necessary, may be stirred or mixed by a usual method. can get. The method of using the composition of the present invention may be in accordance with a method conventionally used for coating wood. For example, by brushing, a roll coater method, a flow coater method, a spray method, a vacuum coating method, or a method such as a dipping method, after applying the composition of the present invention to a wood surface, or irradiating an active energy ray, or A method of curing by heating and the like can be given.

Various woods can be used as a base material on which the composition of the present invention is applied. For example, cherry, red oak, rosewood, karin, mahogany, lauan, mulberry, boxwood, kaya, yellowfin, how, wig, Including natural wood such as zelkova, walnut, kusu, oak, cedar, teak, oyster, Jindai wig, Jindai cedar, black oyster, kokutan, shimakokutan, tochi, maple, willow and ash, plywood,
Processed wood such as laminates, particle boards, and printed plywood, and floor materials, furniture, and wall materials manufactured from these natural or processed woods are included.

The thickness of the composition of the present invention may be appropriately selected according to the intended use.
To 200 μm, and more preferably 10 to 50 μm. Examples of the active energy ray include an ultraviolet ray, an X-ray, and an electron beam. Various light sources can be used as a light source that can be used for curing with ultraviolet light, and examples thereof include a pressurized or high-pressure mercury lamp, a metal halide lamp, a xenon lamp, an electrodeless discharge lamp, and a carbon arc lamp. In the case of curing with an electron beam, various irradiation devices can be used, and examples thereof include a Cockloft-Waldsin type, a Bandegraf type or a resonance transformer type, and the electron beam preferably has an energy of 50 to 1000 eV. , More preferably 100 to 300
eV. In the present invention, it is preferable to use ultraviolet rays for curing the composition, since an inexpensive apparatus can be used. When the composition is cured by heating, a heating furnace, infrared rays, microwaves, and the like can be used as a heat energy source.

[0084]

The present invention will be described more specifically with reference to examples and comparative examples. The parts in the following examples are on a weight basis.

Examples 1 to 10 The components shown in Table 1 were dissolved and mixed to produce an active energy ray-curable coating composition for coating wood. (Evaluation test) The obtained composition was placed on oak veneer plywood,
Using a bar coater, apply a film having a thickness of 30 μm.
0 W / cm, 10 cm below the condensing high pressure mercury lamp
At the position, the sheet was repeatedly passed under a mercury lamp and cured under a condition of a conveyor speed of 5 m / min. The following evaluation was performed about the obtained composition and the coating film. Table 2 shows the results.

(Curability) Under the above curing conditions, evaluation was made by the number of passes (the number of passes) until the surface was free of tackiness.
The smaller the number of passes, the better the curability.

(Adhesion) The obtained coating film was evaluated for adhesion according to the JIS K 5400 X-cut tape method. The higher the value, the better the adhesion.

(Pencil hardness) According to JIS K 5400.

The abbreviations in Table 1 have the following meanings. Epolite 1600: Kyoeisha Chemical, hexanediol diglycidyl ether YD-128: Toto Kasei, bisphenol A diglycidyl ether UVR-6110: Union Carbide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate UVR -6128: manufactured by Union Carbide, bis (3,4-epoxycyclohexylmethyl) adipate celloxide 3000: manufactured by Daicel UCB, limonene diepoxy EOXA: manufactured by Toagosei, 3-ethyl-3hydroxymethyloxetane XDO: manufactured by Toagosei, Xylylenedioxetane M-240: Toagosei, polyethylene glycol diacrylate M-101: Toagosei, monoacrylate of ethylene oxide adduct of phenol M-111: Toagosei, monoacrylate of ethylene oxide adduct of nonylphenol M -350: OTA-480: Triacrylate of propylene oxide adduct of glycerin manufactured by Daicel UCB Co., Ltd. PET4PO4A: Tetraacrylate of propylene oxide adduct of pentaerythritol M-305: Triacrylate of pentaerythritol, manufactured by Toagosei Co., Ltd. VE: Vinyl ether represented by the following formula; CH ₂ = CHO- (CH ₂ CH ₂ O) ₃ -CH = CH ₂ UVI-6990: Triarylsulfonium hexafluoro manufactured by Union Carbide Phosphate salt Irg184: Ciba Specialty Chemicals, 1-hydroxycyclohexyl phenyl ketone

Comparative Examples 1 to 5 Curable coating compositions for wood coating were produced in the same manner as in Example 1 except that the components having the compositions shown in Table 1 were used. The obtained coating film was evaluated in the same manner as in Example 1. Table 2 shows the results.

[0091]

[Table 1]

[0092]

[Table 2]

[0093]

The curable coating composition for wood coating of the present invention has a high curing speed, and its coating film has excellent adhesion and pencil hardness, and is extremely practical.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ichiro Igarashi 1 in Funami-cho, Minato-ku, Nagoya-shi, Aichi Prefecture Inside Nagoya Research Institute, Toagosei Co., Ltd. (72) Inventor Kunihiko Funami-cho, Minato-ku, Nagoya-shi, Aichi No. 1 Toagosei Co., Ltd. Nagoya Research Laboratory (72) Inventor Satoshi Yoshiyama 8-10 Wakamatsucho, Takatsuki-shi, Osaka Capital Paint Co., Ltd. (72) Inventor Yoshio Mizoguchi 4 Tsudakaigan-cho, Tokushima-shi, Tokushima No. 59 F-term in Albolex, Inc. (reference) 4J036 AA01 AJ08 EA04 EA09 FB16 JA01 4J038 DB031 DB032 DB041 DB042 DB091 DB092 DB261 DB262 DL052 FA151 FA152 GA02 GA07 JA69 JB08 JC01 JC34 NA01 PA17 PB05 PC06

Claims (4)

[Claims] 1. The following components (a) and (b): (a) a compound having two or more epoxy groups in one molecule, and (b) a (meth) acrylate compound having an alkylene oxide unit in one molecule. , A curable coating composition for coating wood. 2. The curable coating material for wood coating according to claim 1, further comprising the following component (c): (c) a compound having 1 to 4 oxetane rings in one molecule. Composition. 3. The curable coating composition for wood coating according to claim 1, wherein the component (a) is a compound having an alicyclic epoxy group. 4. The component (b) is a (meth) acrylate of an alkylene oxide adduct of trimethylolpropane, a (meth) acrylate of an alkylene oxide adduct of glycerin, and a (meth) acrylate of an alkylene oxide adduct of pentaerythritol. And at least one member selected from the group consisting of:
The curable coating composition for coating wood according to any one of claims 3 to 7.