JPH0224853B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides excellent curing properties in air by coating the base surface of a resin molded article, and the coating has excellent surface hardness, scratch resistance, abrasion resistance, flexibility, surface gloss, heat resistance, water resistance, and The present invention relates to a curable resin composition for coating that has excellent coating properties such as solvent resistance, weather resistance, and adhesion to the surface of a molded body substrate. In general, resin moldings such as thermoplastic resins and thermosetting resins are not only lighter and have better impact resistance than metal products and glass products, but also are inexpensive and easy to mold. It has advantages and is suitable for automobiles, motorcycles, household appliances,
It is widely used in place of these materials in daily necessities and many other fields. but,
These resin molded substrates have a lower surface hardness than metals, glass, etc., and are vulnerable to scratching and friction, so they have the drawback of being easily scratched on the surface.
For example, the use of these molded products is significantly reduced due to defects in surface properties such as damage to the surface due to contact, collision, scratching, etc. during installation or transportation of parts of molded products, or during use of the product. Limited. Many proposals have been made as methods for improving the above-mentioned defects of the surface of the resin molded body substrate.
Most of these methods involve coating the surface of these molded bodies with an outer coating layer made of a crosslinked curable resin.
Among these film-forming elements, specific examples of resins or resin-forming components include silicone monomers or compositions of these components with various polymers, and resin compositions consisting of methylolmelamine and other curing components. , polyfunctional acrylic carboxylic acid ester derivatives, and compositions of these and other polymeric components have been proposed. Even if a film layer made of these film-forming elements is formed on the surface of a base material of a resin molded product such as polyolefin, the adhesion between the film layer and the base layer of the resin molded product is generally not good. The disadvantage is that the coating layer is easily peeled off. Furthermore, methods are known in which various treatments are applied to the surface of the resin molded body base layer in order to improve these defects. For example, surface treatments using corona discharge and primers have been proposed. However, even if surface treatment is performed, it is often difficult to sufficiently improve the adhesion between the base layer of a resin molded product such as polyolefin and the coating layer made of the crosslinked curable resin so as to be practical. Moreover, among the film-forming elements, silicone-based film-forming elements are expensive and have a disadvantage of being inferior in economic efficiency. Among the film-forming elements, various types of compounds have been proposed as polyfunctional acrylic carboxylic acid ester derivatives. for example,
Various types of compounds can be used as film-forming elements, such as poly(meth)acrylates of alkane polyols, poly(meth)acrylates of polyoxyalkylene glycols, and poly(meth)acrylates of aromatic (phenolic) polyhydroxyl compounds. is proposed. Even if these polyfunctional acrylic carboxylic acid ester derivatives are used alone as a film-forming element to form a film on the basic surface of a resin molded product, these films will not be affected by the curing speed in air during curing. Poor curing properties or poor coating properties such as surface hardness, scratch resistance, abrasion resistance, flexibility, surface gloss, heat resistance, water resistance, solvent resistance, weather resistance, and adhesion to the substrate. However, many of these physical properties are often inferior, and it has not been possible to fully satisfy the requirements for industrial scale use. In addition, attempts have been made to improve these drawbacks by using a combination of two or more compounds among these film-forming elements, but none of them have been able to improve these drawbacks to some extent. However, there were other new difficulties when coating the surface of a base material of a molded resin such as polyolefin. The present inventors have developed a coating material that has excellent curing properties during curing and has excellent coating properties by coating the basic surface of a resin molded article such as a thermoplastic resin or thermosetting resin. As a result of intensive studies, we found that when using a composition containing urethane poly(meth)acrylate a, a specific amount of a poly(meth)acrylate of an aliphatic polyester polyol compound b, and a specific amount of polymerization initiator c. It has been discovered that the above object is satisfied, and the present invention has been achieved. According to the present invention, when the curable resin composition for coating of the present invention is coated on the surface of a resin molded body substrate to form an outer coating layer, it has excellent curing properties such as curing speed in air during curing, Many coating properties such as surface hardness, scratch resistance, abrasion resistance, flexibility, surface gloss, heat resistance, water resistance, solvent resistance, weather resistance, and adhesion to the substrate are comprehensively evaluated. It has excellent characteristics. To summarize the present invention, the present invention comprises (a) a urethane poly(meth)acrylate having two or more acryloyloxyl groups or methacryloyloxyl groups and one or more urethane bonds in one molecule; (b) 5 to 700 parts by weight per 100 parts by weight of the urethane-based poly(meth)acrylate compound a, having two or more acryloyloxyl groups or methacryloyloxyl groups in one molecule and having a urethane bond. It is a poly(meth)acrylate of aliphatic polyester polyol, and its number average molecular weight is
300 to 5000, and (c) based on the total weight part of the urethane poly(meth)acrylate a and the poly(meth)acrylate of the polyester polyol b.
A composition for resin coating, characterized in that it contains a polymerization initiator in the range of 0.01 to 20 parts by weight,
The main points are as follows. Urethane poly(meth)acrylate compound a blended into the curable resin composition for coating of the present invention
is a (meth)acrylate polyfunctional compound having one or more urethane bonds and two or more acryloyloxyl groups or methacryloyloxyl groups in one molecule. Specifically, urethane poly(meth)acrylate compounds obtained by the reaction of (meth)acrylic esters having hydroxyl groups with diisocyanate compounds, urethane poly(meth)acrylates of polyurethane polyols, etc. Examples include (meth)acrylate compounds, urethane-based poly(meth)acrylate compounds made of poly(meth)acrylate of polyester-based polyurethane polyols, and the like. The polyol component units constituting these urethane-based poly(meth)acrylate compounds include aliphatic polyols, alicyclic polyols, aromatic polyols, polyoxyalkylene glycols, polyoxyalkane polyols, and arylene bis[polyoxyalkanes]. Examples include polyol, polyester polyol, polyurethane polyol, polyester polyurethane polyol, polyurea polyol, and more specifically ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, octylene glycol, glycerin, and trimethylol. Propane, pentaerythritol, diethylene glycol, triethylene glycol, dipropylene glycol,
Dibutylene glycol, dihexylene glycol, diglycene, ditrimethylolpropane, dipentaerythritol, polyoxyethylene glycol, polyoxyethylene/polyoxypropylene glycol, polyoxypropylene glycol, polyoxybutylene glycol, cyclohexylene glycol, 2,2- Bis(4-hydroxycyclohexyl)propane, bis(4-hydroxycyclohexyl)methane, 2,2-bis(4
-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)ethane, bis(4-
hydroxyphenyl)methane, bis(acryloyloxyethyl)hydroxyethyl isocyanurate, bis(methacryloyloxyethyl)hydroxyethyl isocyanurate;
Acrylates; the various polyhydric alcohol component units and succinic acid, glutanic acid, adipic acid, suberic acid, sebacic acid, maleic acid, fumaric acid, itaconic acid, tetrahydrophthalic anhydride, hexahydroanhydride, phthalic acid, phthalic anhydride Examples include polyester polyols formed from polyhydric carboxylic acid component units such as acid, trimellitic acid, and pyromellitic acid; polyurethane polyols formed from the various polyol component units described above and various diisocyanate component units described below. Can be done. In addition, these urethane-based poly(meth)
The diisocyanate component unit constituting the acrylate compound may be any component unit of aliphatic diisocyanate, alicyclic diisocyanate, or aromatic diisocyanate. It may be a dinitrile biscarbonate compound corresponding to the component unit or a biscarbamate compound corresponding to these diisocyanate component units. Specifically, the diisocyanate component units of the constituent components include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate, Methylcyclohexane-2,4-diisocyanate 3-isocyanatomethyl-3,5,5-
trimethylcyclohexyl isocyanate, 4,
4′-dicyclohexylmethane diisocyanate,
Examples include isopropylidene bis(4-cyclohexyl isocyanate), phenylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, and bistryl diisocyanate. A poly(meth)acrylate of a polyurethane polyol is obtained by reacting the polyurethane polyol with acrylic acid or methacrylic acid according to a conventional method in the presence of a catalyst if necessary, and similarly the polyester-based polyurethane polyol and acrylic acid are reacted. Poly(meth)acrylate of polyester-based polyurethane polyol can be obtained by reacting with acid or methacrylic acid. Among the urethane-based poly(meth)acrylate compounds, the hydroxyl group constituting the urethane-based poly(meth)acrylate compound obtained by the reaction of a (meth)acrylic acid ester having a hydroxyl group with a diisocyanate compound is Examples of the (meth)acrylic acid ester component unit include a reaction product of a polyhydroxyl group-containing compound and (meth)acrylic acid, a reaction product of an epoxy compound and (meth)acrylic acid, etc. Specifically, acrylic acid 2 -Hydroxyethyl, methacrylic acid 2
- Hydroxyethyl, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, acrylate of glycidyl acrylate, methacrylate of glycidyl acrylate, acrylate of glycidyl methacrylate, methacrylate of glycidyl methacrylate, Glycerin monoacrylate, glycerin monomethacrylate, glycerin-1,3 diacrylate, glycerin-
1,3-dimethacrylate, trimethylolpropane monoacrylate, trimethylolpropane monomethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate pentaerythritol monoacrylate, pentaerythritol monomethacrylate,
Pentaerythritol diacrylate, pentaerythritol dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol monoacrylate, dipentaerythritol monomethacrylate, dipentaerythritol diacrylate, dipentaerythritol dimethacrylate, dipentaerythritol triacrylate , dipentaerythritol trimethacrylate, dipentaerythritol tetraacrylate, dipentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, bis(acryloyloxyethyl)hydroxyethyl isocyanurate, bis(methacryloyloxyethyl)hydroxyethyl Isocyanurate, cyacrylate of propylene glycol diglycidyl ether, dimethacrylate of propylene glycol diglycidyl ether,
Diacrylate of glycerin-1,3-diglycidyl ether, dimethacrylate of glycerin-1,3-diglycidyl ether, triacrylate of glycerin triglycidyl ether, trimethacrylate of glycerin triglycidyl ether, pentaerythritol diglycidyl Diacrylate of ether, dimethacrylate of pentaerythritol diglycidyl ether, triacrylate of pentaerythritol triglycidyl ether, trimethacrylate of pentaerythritol triglycidyl ether, 2,2-bis(4-hydroxycyclohexyl)propane diglycidyl Diacrylate of ether, dimethacrylate of 2,2-bis(4-hydroxycyclohexyl)propane diglycidyl ether, 2,2-bis(4
-Hydroxyphenyl)propane diglycidyl ether diacrylate, 2,2-bis(4
Examples include dimethacrylates of -hydroxyphenylpropane diglycidyl ether, and examples of the diisocyanate component units include the compounds listed above. The urethane-based poly(meth)acrylate compound b
Among these, when a urethane poly(meth)acrylate compound containing an aliphatic alkylene diisocyanate component unit or an alicyclic diisocyanate component unit as a diisocyanate component unit is used, the hue of the cured film changes. This is preferable because it improves weather resistance, flammability, etc. The poly(meth)acrylate b of polyester polyol blended into the curable resin composition for coating of the present invention has at least two acryloyloxyl groups or methacryloyloxyl groups in one molecule and has a urethane bond. It is a poly(meth)acrylate of an aliphatic polyester polyol that does not have Here, the polyester polyol constituting the poly(meth)acrylate of the polyester polyol is formed by polycondensing a polycarboxylic acid and a polyol. It is a polyester polyol having hydroxyl groups. Examples of the polycarboxylic acid component units constituting the polyester polyol include oxalic acid, malonic acid, succinic acid, glutaric acid,
Aliphatic polycarboxylic acids such as adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, brassylic acid, maleic acid, fumaric acid, itaconic acid, butanetricarboxylic acid, butanetetracarboxylic acid, etc. I can give an example. Examples of the polyol component units constituting the polyester polyol include ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, octylene glycol, glycerin, trimethylolpropane, pentaerythritol, diethylene glycol, triethylene glycol, dipropylene glycol, Aliphatic polyols such as dibutylene glycol, tributylene glycol, dihexylene glycol, diglycerin, ditrimethylolpropane, dipentaerythritol, polyoxyethylene glycol, polyoxyethylene polyoxypropylene glycol, polyoxypropylene glycol, polyoxybutylene glycol ,
For example, Among the polyester polyol components formed from these polycarboxylic acid component units and polyol component units, an aliphatic polyester polyol component is particularly preferred. By reacting the polyester polyol and acrylic acid or methacrylic acid in the presence of a catalyst as necessary,
Poly(meth) of aliphatic polyester polyol
An acrylate is obtained. The number average molecular weight of the poly(meth)acrylate of the polyester polyol is in the range of 300 to 5,000. The blending ratio of the poly(meth)acrylate compound b of the polyester polyol is 5 parts by weight based on 100 parts by weight of the urethane poly(meth)acrylate compound.
It is preferably in the range from 10 to 700 parts by weight, particularly in the range from 10 to 500 parts by weight. The urethane-based poly(meth)acrylate compound of the poly(meth)acrylate compound b of the polyester-based polyol
If the blending ratio is more than 1000 parts by weight based on 100 parts by weight of a, the wettability of the composition to the molded body substrate, the flexibility of the coating, etc. will decrease. The film forming element component (polymerizable monomer component) blended into the curable resin composition for coating of the present invention may consist of only the above-mentioned two essential components, but may further include other polymerizable monomer components. In addition, copolymerization is also possible. Examples of other polymerizable monomer components include urethane mono(meth)acrylate compounds or mono(meth)acrylates of polyester polyols, (meth)acrylic acid, methyl (meth)acrylate, and (meth)acrylic acid. Examples include (meth)acrylic acid esters such as -2-hydroxyethyl. In order to apply the curable resin composition for coating of the present invention to the surface of a substrate of a molded article and crosslink and cure the composition to form a film, a polymerization initiator c is added to the composition.
It is necessary to incorporate As the curing method, a curing method using ultraviolet rays, a curing method using heat rays, etc. are usually employed. In the case of ultraviolet curing, a photosensitizer is blended as a polymerization initiator. Specifically, the photosensitizer is benzoin or its like, such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, etc. ether,
Benzophenone, p-chlorobenzophenone, p
-Benzyl compounds such as methoxybenzophenone, benzyl, benzyl dimethyl ketal, benzyl diethyl ketal, 1-(4-isopropylphenyl)-2-
Hydroxy-2-methyl-1-propanone, 1-
Phenyl-2-hydroxy-2-methyl-1-propane, 1-(4-tert-butylphenyl)-2-
Examples include hydroxyalkyl phenyl ketone compounds such as hydroxy-2-methyl-1-propanone. In the case of curing by heat, a radical initiator is blended, and specific examples of the radical initiator include azo compounds such as azobisisobutyronitrile, benzoyl peroxide, lauryl peroxide, di-tert-butyl peroxide, dicumyl peroxide, Examples include peroxides such as cumene hydroperoxide. Furthermore, it is also possible to adopt a method in which both a photosensitizer and a radical initiator are blended into the curable resin composition for coating of the present invention, and UV curing and heat curing proceed simultaneously. It is also possible to adopt a method in which heat curing is progressed after the heat curing is progressed. Furthermore, it is also possible to adopt a method of proceeding with ultraviolet curing after proceeding with heat curing. The blending ratio of the polymerization initiator c is 0.01 parts by weight based on a total of 100 parts by weight of the urethane-based poly(meth)acrylate compound a and the poly(meth)acrylate compound b of the polyester polyol.
It is necessary that the amount is between 20 and 20 parts by weight,
More preferably, the amount is in the range of 0.1 to 10 parts by weight. The blending ratio of the polymerization initiator is 0.01 parts by weight based on a total of 100 parts by weight of the urethane-based poly(meth)acrylate compound a and the poly(meth)acrylate compound b of the polyester-based polyol.
When the amount is less than 20 parts by weight, the polymerizability of the composition decreases and a hard film cannot be obtained, and when it is more than 20 parts by weight, the film obtained from the composition becomes yellow colored. The curable resin composition for coating of the present invention may be a composition consisting only of the above-mentioned three essential components, but may further include a polymerization inhibitor, a transparent filler,
Various additives such as pigments, dyes, solvents, ultraviolet absorbers, stabilizers such as antioxidants, fluorescent whitening agents, and polymers such as polymethyl methacrylate can be blended. The blending ratio of these additives is appropriate. In the curable resin composition for coating of the present invention, within a range that maintains the transparency of the resulting cured film,
If necessary, a finely powdered inorganic filler may be added. The average particle size of the finely powdered inorganic filler is arbitrary as long as it forms a powder, but it is usually 1 mμ to 10μ, preferably 1.5 mμ to 10μ.
It is in the range of 1μ. Further, in order to maintain the transparency of the outer coating layer, the refractive index of the finely powdered inorganic filler is usually in the range of 1.40 to 1.60, preferably 1.42 to 1.58. Specifically, such fine powder inorganic fillers include glass powder, mica, glass beads, glass flakes, diatomaceous earth, anhydrous silica, hydrated silica, silica, silica sand, quartz, kaolinite, montmorillonite, and seri. Examples include silica, talc, chlorite, chinastone, and feldspar. Further, these finely powdered inorganic fillers whose surfaces have been surface-treated with alkyl carboxylic acid salts, silane couplers, titanium couplers, Cl ₂ Si (CH ₃ ) ₂ , alcohol, etc. can also be used. Furthermore, colloidal silica, methanol silica sol, ethanol silica sol, isopropanol silica sol, etc. in which the inorganic filler is suspended in water or alcohol can also be used.
Among these fine powder inorganic fillers, blending fine powder silica significantly improves the surface hardness, scratch resistance and abrasion resistance of the outer coating layer, without impairing transparency and surface gloss. Therefore, it is particularly preferable. The blending ratio of these finely powdered inorganic fillers is usually 0.5 to 200 parts by weight per 100 parts by weight of the urethane poly(meth)acrylate compound a and the poly(meth)acrylate compound b of the polyester polyol. The preferred range is 0.5 to 100 parts by weight. A solvent is added to the curable resin composition for coating of the present invention as necessary to improve its coating workability, and the composition is maintained in a solution state or a suspended state. The solvent is also used for the purpose of liquefying or suspending the composition, adjusting the viscosity of the composition, or improving wetting of the composition.
Specifically, the solvents include benzene, toluene, xylene, cumene, ethylbenzene, hexane, heptane, octane, petroleum ether, ligroin,
Hydrocarbons such as cyclohexane and methylcyclohexane, methylene chloride, chloroform, carbon tetrachloride, bromoform, trichrene, ethylene dichloride, perchloroethane, trichloroethane, tetrachloroethane,
Halogenated hydrocarbons such as propylene dichloride, chlorobenzene, bromobenzene, methanol, ethanol, isopropanol, butanol, pentanol, hexanol, cyclohexanol,
Alcohols such as ethylene glycol, propylene glycol, glycerin, ethylene glycol monomethyl ether, diethylene glycol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diethyl ether, dipropyl ether, butyl ethyl ether, dibutyl ether, ethylene glycol dimethyl ether, diethylene glycol Ethers such as dimethyl ether, nitriles such as acetonitrile, propionitrile, capronitrile,
Examples include esters of methyl formate, ethyl formate, methyl acetate, ethyl acetate, propyl acetate, isobutyl acetate, butyl acetate, pentyl acetate, methyl benzoate, and ethyl benzoate. The blending ratio of these organic solvents is usually 5 to 5 parts by weight per 100 parts by weight of the urethane poly(meth)acrylate compound a and the poly(meth)acrylate compound b of the polyester polyol.
3000 parts by weight, preferably in the range of 10 to 2000 parts by weight. In the composition of the present invention, a composition containing the above-mentioned essential components and various additive components such as an inorganic or organic filler, a solvent, a stabilizer, etc. added as necessary, or a solution composition or a suspension composition. The method for preparing is to prepare the above-mentioned raw material mixture,
Regular roll, Banbury mixer, ball mill,
Examples include kneading and mixing methods using attritors, whitpers, oak mixers, desolvers, homogenizers, colloid mills, sand mills, vibration mills, mixers, mixing tanks, etc., and compositions that are uniformly dissolved or dispersed by these methods. You can get things. Methods for applying the solution composition and suspension composition to the substrate surface of the resin molding include brush coating, spraying, dipping, bar coating, roll coater, spin coater, gel coater, etc. Conventionally known methods can be employed. Examples of methods for drying the coating film include natural drying, forced drying using carrier gas, heating drying using an infrared oven, far-infrared oven, and hot air oven. Also,
Examples of the method for curing the above-mentioned coating film to form a film include a method of polymerization crosslinking and curing using light, particularly ultraviolet rays, and a method of polymerizing and crosslinking and curing using heat. Among these polymerization and crosslinking curing methods, the photocuring method usually has a temperature of -10 to 150
The light irradiation is carried out at a temperature of 0.degree. C., preferably 5 to 130.degree. C., and the duration is usually 1 sec to 1 hr, preferably 1 sec to 10 min. In addition, in the thermosetting method, the temperature during curing is usually -10 to 150°C, preferably 5 to 130°C, and the time required for curing is usually 0.05 to 10 hr, preferably 0.1 to 130°C.
It is 8 hours. The curable resin composition for coating of the present invention can be coated on the substrate surface of any molded article made of a thermoplastic resin or a thermosetting resin. The shape of the molded product may be a film, a sheet, a plate, a molded product having a curved surface or an uneven surface, or any other shape. Specifically, the thermoplastic resin constituting the base layer includes, for example, polyolefins such as a homopolymer of α-olefin or a copolymer mainly composed of α-olefin, polyacrylic acid ester resin, polycarbonate resin, polyester resin,
Examples include polyamide resin. Among these thermoplastic resins, the base resin layer constituting the laminate molded product is preferably polyolefins, polyacrylic ester resins, or polycarbonate resins. Specifically, the polyolefins include homopolymers of α-olefins such as ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene; or a copolymer consisting of a mixture of two or more of the above-mentioned α-olefins, and a lower aliphatic vinyl carboxylate such as vinyl acetate or vinyl propionate;
Contains small amounts (for example, 30 mol% or less) of other components such as acrylic carboxylic acid esters such as methyl acrylate, metal salts of acrylic acid, methyl methacrylate, and metal salts of methacrylic acid, and salts of acrylic carboxylic acids. Examples include copolymers. Among these polyolefins,
Polyolefins having crystallinity are commonly used. Specific examples of the polyacrylic carboxylic acid ester resin include homopolymers or copolymers of acrylic carboxylic acid ester monomers such as methyl acrylate, ethyl acrylate, methyl methacrylate, and ethyl methacrylate. can. Among these polyacrylic carboxylic acid ester resins, polymethyl methacrylate is preferably used in the thermoplastic resin base resin layer of the present invention. Specific examples of the polycarbonate resin include bisphenol A polycarbonate. Specific examples of the polyester resin include polyethylene terephthalate, polytetramethylene terephthalate, bisphenol A/isophthalic acid/terephthalic acid copolycondensate, and oxybenzoic acid polycondensate. Specifically, the polyamide resin includes nylon 6, nylon 6/6, nylon
10, nylon 12, etc. In addition to the above resins, polyacetal, polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer,
polysulfone resin, polyphenylene oxide,
Examples include modified polyphenylene oxide, polyphenylene sulfide resin, and polyether sulfone resin. Specifically, the thermosetting resin constituting the base layer includes unsaturated polyester resin, epoxy resin,
Examples include melamine resin, diallyl phthalate resin, and polyallyl glycol carbonate resin. When coating the base surface of a resin molded body with the curable resin composition for coating of the present invention, the base surface of the molded body may be washed with various solvents, alkaline aqueous solution, surfactant, or ultraviolet. Perform various surface treatments such as sonic cleaning, electrolytic cleaning, blasting, sandblasting, acid or alkali etching, flame treatment, corona discharge treatment, arc discharge treatment, glow discharge treatment, plasma discharge treatment, and chemical conversion treatment. be able to. Furthermore, when laminating an outer coating layer made of the curable resin composition for coating of the present invention on the substrate surface of the molded article, an intermediate adhesive layer made of a primer may be placed between the substrate layer and the outer coating layer. It is also possible to improve the adhesion between both layers by forming a three-layer laminate. When the base layer is polyolefin, the primer may be α,β-unsaturated carboxylic acid, its acid anhydride, its ester, etc.
Modified polyolefins grafted with unsaturated carboxylic acid or derivative components thereof are commonly used.
In this manner, the surface of the base layer of the resin molded body, which has been subjected to surface treatment or primer treatment as necessary, is coated with the composition of the present invention by the method described above, and then subjected to a curing treatment. A resin molded article on which a coating made of the curable resin composition for coating of the present invention is laminated can be used for various purposes. Specifically, examples include daylight panels, sky domes, solar water heater panels, glove box panels, watch glasses, various lenses such as glasses, cameras, and contact lenses, optical prisms, blood bags, and coffee maker panels. Shower domes, coffee dispensers, water tanks, covers for lighting equipment, covers for stereo equipment such as players, dials and covers for various meters, covers for car headlights or taillights, level sensors, films to prevent glass from scattering, and release films. , various films such as insulating films and agricultural films, optical reproduction type video discs, sight windows of various devices such as clothes dryers, electric washing machines, screwdrivers, oil tanks, windshields of motorcycles, jeeps, motor boats, etc., and automobiles. Glass (windshields, rear windows, opera windows, triangular windows, sunroofs), window glass for greenhouses, houses, aquariums, etc., tableware, mirrors, various containers such as oil bottles and cosmetic bottles, relay cases, fuse boxes, and motorcycles. Side covers, mudguards, fenders, curtains, screens, tablecloths, waterproof and moisture-proof films, tarpaulins, insulating films, floor tiles, floor sheets, doors, table boards, wall tiles, countertop decorative boards, shelves, walls Sheets, wallpaper, furniture, lightweight wallboards, tableware, chairs, bathtubs, toilet bowls, refrigerators, wall panels, water supply and drainage pipes, wiring pipes, ducts, curtain rods, rain gutters, insulation materials, waterproof coating materials,
Curtains, window frames, automobile foil, various containers, automobile interior materials, vanity tables, flower boxes, particle boards, roof tiles, shutters, shutters, waterproof pans, pipes, wiring materials, gear cams, knobs, solenoid valve frames,
Examples include fans, instrument panels, bumpers, and brakes. In addition to the above, we also use home appliances, automobile parts, motorcycle parts, vending machine parts, civil engineering and construction materials, general industrial materials, office information equipment, appliances, electronic parts, packaging materials, sports equipment, medical equipment, and nuclear power-related parts. can also be used. Next, the present invention will be specifically explained using examples. In addition, in the main text of the specification or the examples, evaluation was performed by the following method. (1) Refractive index Add 2wt% of a sufficiently dried inorganic substance to a liquid with a known refractive index, and after sufficiently dispersing it, visually check the transparency. The refractive index should be the same as that of the most transparent liquid. (2) Surface gloss (gloss) Measured according to 60 degree specular gloss in JIS K5400-1979. (3) Light transmittance Conducted according to JIS K67.14. (4) Adhesion The test was conducted according to the cross-cut test in JIS K5400-1979. Judgment is based on how many of the 100 pieces are glued together. (5) Sand abrasion 800g of silicon carbide abrasive material is dropped onto the coating according to the method of JIS T8147-1975. Abrasion resistance is expressed by the difference in surface gloss before and after the test.
The smaller the number, the better the wear resistance. (6) Taber wear According to ASTM D-1044 method, wear wheel CS
−10, rotate the film 1000 times with a load of 500 g. Wear resistance is expressed by the amount of wear on the coating after the test. The smaller the amount of wear, the better the wear resistance. (7) Pencil hardness Measured according to JIS K5651. (8) Flexibility A strip test piece with a width of 5 mm and a length of 10 cm is 2 cm in diameter.
It is expressed as the angle at which the coating cracks or peels off from the base when folded along the outer circumference of the cylinder. The larger the value, the better the flexibility. (9) Water resistance After immersing the test piece in pure water at 40℃ for 240 hours,
The appearance and adhesion of the outer coating layer were evaluated. (10) Heat resistance After holding the test piece in a gear aging tester at 80°C for 400 hours, the appearance and adhesion of the outer coating layer were evaluated. (11) Volatile oil resistance The appearance and adhesion of the outer coating layer after immersing the test piece in petroleum benzine for 24 hours at room temperature was evaluated. (12) Gasoline resistance The appearance and adhesion of the outer coating layer were evaluated after the test piece was immersed in regular gasoline for 24 hours at room temperature. (13) Heat cycle resistance The test piece was kept in an air oven at 80℃ for 2 hours, then left at room temperature for 1 hour, then kept in a cold room at -30℃ for 2 hours, and then at room temperature for 1 hour. put. This cycle was repeated 10 times, and changes in the appearance of the outer coating layer were visually observed and adhesion was evaluated. (14) Weather resistance Place the test piece in a sunshine weatherometer.
After holding for 400 hours, the appearance and adhesion of the outer coating layer were evaluated. The following reference examples show synthesis examples of polyacrylate compounds of urethane-based polyacrylate compounds and polyester-based polyols. Reference Example 1 100 g (0.3 mol) of diacrylate of propylene glycol glycidyl ether (manufactured by Kyoeisha Yushi Kagaku KK, trade name: Epoxy Ester 70PA)
20 g (0.12 M) of hexamethylene diisocyanate was added to a 500 ml four-necked flask under a nitrogen atmosphere, and stirred at room temperature for 15 hours to form a urethane system consisting of a diacrylate of propylene glycol diglycidyl ether and a hexamethylene diisocyanate component unit. Polyacrylate was synthesized. Reference example 2 Dipentaerythritol pentaacrylate 50
(0.095 mol), a mixture of 30 g (0.064 mol) dipentaerythritol tetraacrylate, 20 g dipentaerythritol hexaacrylate, and 120 g of methyl isobutyl ketone were placed in a 500 ml four-necked flask, and 3-isocyanatomethyl-3,5 was added under a nitrogen atmosphere. , 17.6 g (0.08 mol) of 5-trimethylcyclohexyl isocyanate was added and stirred at room temperature for 15 hours to form dipentaerythritol polyacrylate component units and 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate component units. A methyl isobutyl ketone solution of urethane polyacrylate was synthesized. Reference Example 3 74 g (0.2 M) of bis(acryloyloxyethyl) hydroxyethyl isocyanurate and 100 g of methyl isobutyl ketone were placed in a 500 ml four-necked flask, and 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate was prepared under a nitrogen atmosphere. Add 22g (0.1M) and leave at room temperature.
Stir for 15hr, bis(acryloyloxyethyl)
Hydroxyethyl isocyanurate component unit and 3
-Methyl isocyanate-3,5,5-trimethylcyclohexyl isocyanate component solution of urethane polyacrylate in methyl isobutyl ketone was synthesized. Reference example 4 Pentaerythritol 136g, succinic acid 59g,
3 g of paratoluenesulfonic acid and 100 g of toluene were charged, and an esterification reaction was carried out at 150°C for 2 hours in a nitrogen atmosphere. After cooling, 220 g of acrylic acid, 3 g of hydroquinone, and 200 g of toluene were added, and an esterification reaction was carried out at 120°C for 4 hours. After washing the reaction solution with weak alkaline water and water, 0.05 g of hydroquinone was added and low-boiling substances were distilled off to obtain a polyacrylate of polyester polyol having an average molecular weight of 700. The average number of double bonds in one molecule of this polyacrylate polyester polyol is 4.2.
Confirmed by NMR. Reference example 5 Trimethylolpropane 138g, adipic acid 73g
g, p-toluenesulfonic acid 3g, acrylic acid
A polyacrylate of a polyester polyol having an average molecular weight of 620 and an average number of double bonds per molecule of 3.6 was obtained from 220 g, hydroquinone 3 g, and toluene 400 g in the same manner as in Reference Example 1. Reference example 6 Pentaerythritol 136g, itaconic acid 65.5g
g, acrylic acid 140g, methacrylic acid 100g, toluene 800g, 98% sulfuric acid 6ml and phenothiazine
Prepare 0.2g and heat at 100 to 110℃ for 8 hours in nitrogen atmosphere.
An esterification reaction was performed. After washing the reaction solution with weak alkaline water and water, 0.05 g of hydroquinone was added and low-boiling substances were distilled off to obtain a poly(meth)acrylate of polyester polyol with an average molecular weight of 750 and the number of acryloyloxyl groups per molecule of 5.3. Ta. Reference example 7 Pentaerythritol 136g, diethylene glycol 106g, succinic acid 177g, acrylic acid 240g
The average molecular weight was determined by the method described in Reference Example 3 except that
1200, a polyacrylate of polyester polyol having an average number of double bonds in one molecule of 5.5 was obtained. Example 1 70 g of the urethane polyacrylate compound described in Reference Example 1, 30 g of the polyacrylate of the polyester polyol described in Reference Example 4, 5 g of benzoin isopropyl ether, 70 g of methyl isobutyl ketone, and 80 g of toluene were placed in a 500 ml four-necked flask. The mixture was stirred at room temperature for 2 hours to prepare a transparent coating composition [A]. On the other hand, polypropylene (Mitsui Petrochemical Industries KK)
An injection square plate (thickness: 3 mm) made from 1,1,1-trichloroethane (manufactured by Mitsui Petrochemical Polypropylene SJ-313) was exposed to 1,1,1-trichloroethane vapor for 1 minute, then dried at room temperature for 1 minute, and then exposed to maleic anhydride. degeneration
The injection square plate was immersed in a 15 g/l toluene solution [B] of PER (propylene content 67 mol%, maleic anhydride content 6 wt%) for 20 seconds and slowly pulled up. After drying at room temperature for 5 minutes, heat drying was performed at 80° C. for 30 minutes. Next, the primer-treated polypropylene square plate was immersed in the coating composition [A] for 30 seconds, slowly pulled up, and then dried at room temperature for 1 minute and then at 60° C. for 5 minutes. This test piece was placed under a 1.5KW high-pressure mercury lamp (120w/cm) for 15cm.
The outer coating layer was cured by irradiating it with ultraviolet light for 30 seconds at a distance of . Table 1 shows the performance of this coating. Examples 2 to 5 In Example 1, instead of using the coating composition [A] described in Example 1, the urethane-based poly(meth)acrylate compounds described in Table 1,
Example 1 except that a coating composition prepared using a polyacrylate of polyester polyol, a polymerization initiator, and a solvent in the amounts listed in Table 1 was used.
A test piece with a polypropylene surface coated was prepared in the same manner as above. The results are shown in Table 1. Examples 6 to 7 Urethane poly(meth)acrylate compounds listed in Table 1, polyacrylates of polyester polyols, polymerization initiators, and 1,1,1
- Weigh out the amount of trichloroethane listed in Table 1 and add to this mixture, while stirring, fine powdered silica with an average particle size of 20 mμ and a refractive index of 1.45 (manufactured by Nippon Aerosil KK,
(trade name: R-972) was gradually added (the amount used is shown in Table 1) and stirred thoroughly until uniform dispersion was obtained. Thereafter, the mixture was transferred to an attritor (manufactured by Mitsui Miike Seisakusho KK) filled with steatite balls, and mixed for 3 hours by rotating an agitator at 150 rpm while cooling the tank with water. Then add the amount of toluene listed in Table 1 and add 10
After mixing for a minute, the mixture was taken out from the attritor and used as a coating composition [A]. In Example 1, a test piece having a polypropylene surface coated was prepared by the method described in Example 1, except that the coating composition described in Example 1 was used instead of the coating composition described in Example 1. The results are shown in Table 1. Comparative Examples 1 and 2 For coatings prepared by measuring the amounts of the urethane polyacrylate compound, polyacrylate of polyester polyol, polymerization initiator, and solvent listed in Table 1 and stirring and mixing at room temperature for 2 hours. A test piece whose surface was coated with polypropylene was prepared by the method described in Example 1 except that composition [A] was used. The results are shown in Table 1. Comparative Example 3 Single polypropylene (manufactured by Mitsui Petrochemical Industries KK, SJ-
Table 1 shows the performance of 313). The abbreviations used in Table 1 below represent the following compounds, respectively.

【table】

[Table] Example 8 3 mm of poly-4-methyl-1-pentene (manufactured by Mitsui Petrochemical Industries KK, trade name: TPX-MX004)
Thick injection molded sheet modified with maleic anhydride
15g/EPR (maleic anhydride content: 7.7wt%)
1,1,1-trichloroethane solution at a concentration of 10
Primer treatment was performed by dipping for a second. 5 at room temperature
After standing for a minute, it was immersed in the coating composition described in Example 7 for 10 seconds. After drying at room temperature for 1 minute and then at 60° C. for 5 minutes, the sample was photopolymerized by the method described in Example 7 to prepare a test piece whose surface was coated with poly-4-methyl-1-pentene. The results are shown in Table 2. Examples 9-10 In Example 8, poly-
Instead of using 4-methyl-1-pentene, Table 2
Using a polymer sheet with a thickness of 3 mm as described in
A test piece having a polymer surface coated thereon was prepared by the method described in Example 8, except that the pretreatment described in Table 2 was performed. The results are shown in Table 2. Comparative Examples 4 to 6 Polymers not coated with the coating composition of the present invention
4-Methyl-1-pentene (Mitsui Petrochemical Industries)
Table 2 shows the performance of polycarbonate (Panlite L-1250, manufactured by Teijin Kasei KK), and polymethyl methacrylate (Acrylite L, manufactured by Mitsubishi Rayon KK).

[Table] Example 11, Comparative Example 7 In Example 1, the coating composition [A] described in Example 7 was used instead of the coating composition [A] described in Example 1, and molding was performed. The surface of the unsaturated polyester resin was coated by the method described in Example 1, except that instead of using polypropylene as the body substrate, a 2 mm thick unsaturated polyester resin (Rigoratsu MCS-302 manufactured by Showa Kobunshi KK) was used. A test piece was prepared. The film thickness of this test piece is 8μ,
The surface gloss was 83, the adhesion was 100/100, and the pencil hardness was 4H (Example 11). On the other hand, the unsaturated polyester resin not coated with the coating composition of the present invention had a surface gloss of 63 and a pencil hardness of 3H (Comparative Example 7).

Claims (1)

[Scope of Claims] 1 (a) A urethane-based poly(meth)acrylate compound having two or more acryloyloxyl groups or methacryloyloxyl groups and one or more urethane bonds in one molecule. (b) A urethane bond having two or more acryloyloxyl groups or methacryloyloxyl groups in one molecule, in the range of 5 to 700 parts by weight, based on 100 parts by weight of the urethane-based poly(meth)acrylate compound a. A poly(meth)acrylate of an aliphatic polyester polyol, which has a number average molecular weight of 300
to 5000, and. (c) containing a polymerization initiator in the range of 0.01 to 20 parts by weight based on a total of 100 parts by weight of the urethane-based poly(meth)acrylate compound a and the poly(meth)acrylate of the polyester-based polyol b; Characteristic resin coating composition. 2. A patent in which a finely powdered inorganic filler is blended in an amount of 0.5 to 200 parts by weight with respect to a total of 100 parts by weight of the urethane poly(meth)acrylate compound a and the poly(meth)acrylate compound b of the polyester polyol. The curable resin composition for coating according to claim 1.