KR0148852B1 - Uv hardening paint composition - Google Patents

Abstract

The present invention relates to a UV-curable paint composition, consisting of a non-reactive oligomer, a reactive oligomer, a reactive monomer, a photoinitiator, a leveling agent and an additive which is a polyvinyl acetal derivative represented by the following formula (1), which is easily resistant to UV-curable varnishes It is a UV curable coating composition that has greatly improved physical properties such as scratch resistance and weather resistance, and is excellent in heat resistance that does not discolor when the molded article is coated with metal and polyester molded articles for a long time by heat and does not degrade physical properties.

In which R is a hydrogen atom, a methyl group or a butyl group,

n is an integer of 100-2000.

Description

UV Curing Paint Composition

The present invention relates to a UV-curable paint composition, and more particularly, to a paint composition including a reactive oligomer, a reactive monomer, a non-reactive oligomer, a photoinitiator and a leveling agent, and a non-reactive polyvinyl acetal derivative having a certain degree of acetalization and polymerization degree. It is added as an oligomer and coated on plastic molded products and metals such as polycarbonate, polystyrene, polyester, acrylonitrile-butadiene-styrene, polyflopropylene or polyethylene to improve the aesthetics and durability of the molded products and to coat polyester and metal body It relates to an ultraviolet curable paint composition that can improve post adhesion and heat resistance.

Polycarbonate. Plastic moldings such as polystyrene, polyester, acrylonitrile-butadiene-styrene, polyflopropylene or polyethylene have been used mostly as a substitute for glass, and have the advantage of being easy to process except for their excellent gloss and impact resistance. Its usage continues to increase because of its ability to solve problems such as pollution, pollution, and cost reduction.

However, the molded articles have a weaker disadvantage than glass in terms of abrasion resistance, scratch resistance, heat resistance, and the like.

Thus, attempts to remedy such drawbacks have been made for a long time. However, these techniques have to be exposed to heat for a long time in order to form a coating film as a thermosetting paint. Various adverse effects on the physical properties, especially in terms of adhesion with the metal has been raised.

In order to solve the above problems, an ultraviolet curable paint composition containing two acryloyloxy groups has been proposed (Japanese Patent Laid-Open Nos. 63-150355, 63-221119, 59-117561, Hei 1-267609). No. 1-165631).

In particular, Japanese Unexamined Patent Application Publication No. 1-165631 prepared an ultraviolet curable varnish using non-reactive resins such as polymethyl methacrylate and polyvinylacetate and acrylic or methacryl ester resins of four or more polyglycidyl ethers. These UV cured varnish cured products have the disadvantages of poor physical properties such as abrasion resistance, scratch resistance, and weather resistance, and the disadvantages of poor adhesion to metals. There is a problem of poor quality.

Therefore, the object of the present invention is improved wear resistance, scratch resistance and weather resistance, adhesion to metal, especially heat resistance that does not discolor and physical properties are not degraded when used for a long time by heat after coating on metal and polyester molded article An excellent ultraviolet curable coating composition is provided.

Another object of the present invention is to coat a plastic molded article such as polycarbonate, polystyrene, styrene-acrylonitrile, polyester, acrylonitrile-butadiene-styrene, polyethylene, polypropylene, and the like to form a cured coating film having improved aesthetics and durability. To provide.

UV-curable coating composition of the present invention for achieving the above object is 5 to 60% by weight of a non-reactive oligomer, a polyvinyl acetal derivative having acetalization degree of 30 to 80% represented by the following formula (1), urethane acrylate, polyester acrylic 5 to 80% by weight of at least one reactive oligomer selected from acrylate, epoxy acrylate and polyether acrylate, 5 to 60% by weight reactive monomer selected from acrylate compounds having mono-, di-, tri- and polyfunctional groups, benzo 0.1 to 20% by weight of one kind of photoinitiator selected from phenone, benzyl dimethyl ketal, acetophenone, anthraquinone and thioxoxanthone, 0 to 10% by weight of a leveling agent selected from silicon or fluorine and a small amount of additives UV curable paint composition.

In which R is a hydrogen atom, a methyl group or a butyl group,

n is an integer of 100-2000.

The present invention will be described in more detail as follows.

The non-reactive oligomer used in the present invention is a polyvinyl acetal derivative represented by the formula (1) does not participate in the reaction during the curing reaction by ultraviolet light but remaining in the cured coating film by utilizing the intrinsic properties of the polyvinyl acetal derivative, wear resistance of the coating film, It serves to improve scratch resistance, weather resistance, adhesion to metal and heat resistance.

In the non-reactive oligomer represented by Formula 1, an acetal derivative may be obtained by reacting aldehyde and hydrochloric acid in an aqueous polyvinylacetate solution at 20 to 60 ° C. or adding sulfuric acid to an alcohol solution of polyvinylacetate.

When such a polyvinyl acetal derivative is added to a conventional photocurable paint, it may adversely affect paint properties. Therefore, the polyvinyl acetal derivative should be added in consideration of acetalization degree and polymerization degree.

In consideration of this, the non-reactive oligomer has a polymerization degree of 100-2000 which is soluble in an organic solvent, and an acetalization degree of about 30-80% is used. When the acetalization degree is less than 30%, heat resistance, abrasion resistance, and scratch resistance are somewhat increased. If it exceeds 80%, it is excellent in heat resistance but insoluble in organic solvents.

Therefore, when the appropriate degree of acetalization of the non-reactive oligomer represented by Formula 1 is about 30 to 80%, wear resistance, scratch resistance, heat resistance and weather resistance of the coating film surface are improved.

The non-reactive oligomer can be used 5 to 80% by weight in the composition of the varnish, if less than 5% by weight is poor adhesion with the metal, if more than 80% by weight, such as poor workability and workability, such as viscosity of the varnish In consideration of workability, it is preferable to use 10 to 60% by weight.

In the present invention, the reactive oligomer is one or more selected from urethane acrylate, polyester acrylate, epoxy acrylate and polyether acrylate.

Since the content of such a reactive oligomer is 5 to 80% by weight in the total composition, it is preferable to use 10 to 80% by weight in consideration of curability, cured product properties, workability, and the like.

In addition, the reactive monomers used in the present invention may be polymerized with the reactive oligomers to affect the physical properties of the coating film, and one or more monomers may be used. The mainly used monomers are monofunctional, bifunctional, trifunctional, and polyfunctional monomers. There is this.

Specific examples of the double monofunctional monomers include 2-ethylhexyl acrylate, octyldecyl acrylate, isodecyl acrylate, tridecyl methacrylate, 2-phenoxyethyl acrylate, nonylphenol ethoxylate monoacrylate, and detra. Hydroperfurate ethoxyethyl acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate or hydroxybutyl methacrylate, etc. As the bifunctional monomer, 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, diethylene glycol diacrylate, and 1,4-butanediol diacryl Rate, 1,6-hexanediol diacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, neo Pentyl glycol diacrylate, ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, tripropylene glycol diacrylate, 1,6-hexanediol diacrylate, and the like. The monomers include trimethylolpropanetriacrylate, trimethylolpropanetrimethacrylate, pentaerythritoltriacrylate, glycidylpentatriacrylate, glycidylpentatriacrylate, and the like. Erythritol pentaacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, etc., 1,6-hexanediol diacrylate, tripropylene glycol diacrylate, trimethylol propane tree in consideration of the physical properties of the coating film Acrylate or pentaerythritol tetraacrylate, etc. It is used for.

Since the content of such a reactive monomer is 5 to 80% by weight of the total composition of the non-nish composition, it is preferable to use about 10 to 60% by weight in consideration of cured product properties and workability.

The photoinitiator uses a conventional polymerization initiator exhibiting activity by ultraviolet rays, and compounds such as benzophenone, benzyl dimethyl ketal, acetophenone, anthraquinone or thioxanthone based 0.1 to 20 in the whole varnish composition. It is contained in weight%.

Specific examples of such photoinitiators mainly use hydroxy-cyclohexyl phenylketone, 2,2-dimethoxy-2-phenylacetophenone, benzophenone or phenyl-2-hydroxy-2-propylketone.

It is suitable to use a leveling agent about 0 to 10 weight% of a silicone type and a fluorine type compound.

In case of coating the paint composition of such composition on plastic molding and metal, the painting work is spraying, dipping, or roller coating, which can be selected according to the plastic material, metal type, shape of the molded article or coating thickness. .

At this time, different viscosity is required depending on the coating method, which is possible by adjusting the viscosity by adding an appropriate amount of volatile solvent.

At this time, the volatile solvent to increase the adhesion of the coating film by giving a chemical impact to the plastic and metal material before curing during the painting work, specific examples are ketones, alcohols, acetates or aromatic compounds selected one or more of them Use by mixing.

The amount of use varies depending on the desired viscosity, workability, and the like, and can be usually used as varnish: solvent in a weight ratio of 4: 1 to 1: 4.

Other additives can use a well-known compound by changing the addition amount according to general requirements.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited by the Examples.

Example 1

40 g of bifunctional urethane acrylates (product of diameter UCB company, brand name EBECRYL284), 20 g of non-reactive oligomers (S-LEC-BM-1: acetalization degree 78% by SEKSIUI, Japan), 20 g of trimethylolpropane triacrylates, 1,6- 16.5 g of hexanediol diacrylate, 2 g of 2,2-dimethoxy-2-phenylacetophenone, and 0.5 g of silicone polyacrylate (EBECRYL 360, a diameter UCB) were stirred at 50 ° C to prepare an ultraviolet curable varnish.

Example 2

40 g of epoxy acrylate produced by addition reaction of 1 mole of acrylic acid to 1 mole of bisphenol A type epoxy resin (Korea Chemical Co., Ltd., KOROX R8828, Epoxy equivalent: 184 to 194), 28 g of polyvinylacetate (polymerization degree: 200), butanol 205 g of sulfuric acid was added to 7.7 g of sulfuric acid, and after 30 minutes, 14.5 g of butylaldehyde was reacted and reacted for 4 hours at 30 to 70 ° C. to thereby distill off the solvent to remove the non-reactive oligomer (55% of acetalization) of Example 1 An ultraviolet curable varnish was prepared in the same composition and content as in Example 1 except that 20 g was used instead of the oligomer.

Example 3

40 g of bifunctional polyurethane acrylate (EBECRYL284 manufactured by UCB, USA), 28 g of polyvinylacetate (polymerization degree: 400), 125 g of ethanol and 125 g of ethyl acetate were added to 29.4 g of sulfuric acid, followed by chlorinated butyl aldehyde 15.9 g. An ultraviolet curable varnish was prepared in the same composition and content as in Example 1 except that 20 g of the non-reactive oligomer (67% acetalization degree) precipitated after 6.5 hours at 70 ° C. was used.

Comparative Example 1

60 g of bifunctional urethane acrylates (EBECRYL284 from UCB of diameter), 20 g of trimethylolpropane triacrylate, 16.5 g of 1,6-hexanediol diacrylate, 3 g of 2,2-dimethoxy-2phenylacetophenone, silicone polyacrylate 0.5 g of (EBECRYL360, a diameter of UCB Co., Ltd.) was stirred at 50 ° C to prepare an ultraviolet curable coating composition.

Comparative Example 2

60 g of epoxy acrylate prepared by addition reaction of 1 mole of acrylic acid to 1 mole of bisphenol A epoxy resin (Korea Chemical Co., Ltd., Korepox R8828, Epoxy equivalent: 184 ~ 194) was used instead of the bifunctional urethane acrylate of Comparative Example 1. A UV curable paint composition was prepared in the same composition and content as in Comparative Example 1 except that it was used.

The adhesion, weather resistance, scratch resistance, abrasion resistance and heat resistance of the UV curable paint composition prepared according to the above Examples and Comparative Examples were measured and the results are shown in Table 1 below.

As shown in Table 1, the physical properties of Examples 1 to 3 were superior to those of Comparative Example 1 and Comparative Example 2 in all respects, and among the examples, weather resistance and scratch resistance of Examples 1 and 3 , Abrasion resistance, and heat resistance were superior to those in Example 2.

This is for the non-reactive oligomer used in the present invention to better exhibit all the physical properties of the ultraviolet curable paint composition.

As described in detail above, the paint composition according to the present invention exhibits its intrinsic properties by adding a polyvinyl acetal derivative having a specific degree of acetalization and a degree of polymerization as a non-reactive oligomer, thereby exhibiting abrasion resistance, scratch resistance and weather resistance of a coating film, metal Adhesion is improved, and in particular, after coating on metal and polyester molded articles, the molded article does not discolor when used for a long time by heat and does not lose its physical properties. It is also coated on plastic molded articles and metals for improved aesthetics and durability. It is effective to have.

Claims (1)

At least one reactive selected from 5 to 60% by weight of a non-reactive oligomer, a urethane acrylate, a polyester acrylate, an epoxy acrylate and a polyether acrylate, which is a polyvinyl acetal derivative having an acetalization degree of 30 to 80% 5 to 80% by weight of oligomer, 5 to 60% by weight of reactive monomer selected from acrylate compounds having mono, bi, tri and poly functional groups, benzophenone, benzyl dimethyl ketal, acetophenone, anthraquinone and UV curable paint composition comprising 0.1 to 20% by weight of one kind of photoinitiator selected from thioxoxanthones, 0 to 10% by weight of a leveling agent selected from silicon or fluorine and a small amount of additives. In the formula, R is a hydrogen atom, a methyl group or a butyl group, n is an integer of 100 ~ 2000.