Coating composition and coating film

Abstract

To provide a coating composition which enables formation of a coated film that has antiviral property, antibacterial property, resistance against light degradation discoloration and crack resistance.SOLUTION: A coating composition contains acrylic resin emulsion, a photocatalyst type titanium oxide, and a pigment, wherein a ratio of an aromatic vinyl monomer unit in an acrylic resin of the acrylic resin emulsion is 0-52 mass%, the photocatalyst type titanium oxide contains a metal-carrying anatase type titanium oxide, a content of the metal-carrying anatase type titanium oxide is 0.05 to 2.90 pts.mass with respect to 100 pts.mass of the total solid content of the coating composition, and pigment volume concentration (PVC) of the pigment is 35-65%.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a paint composition and a coating film.

Background Art

[0002] Conventionally, a coating film formed using a paint containing photocatalytic titanium oxide is known to be excellent in antibacterial and antiviral properties because the titanium oxide exhibits a strong redox action when irradiated with light such as ultraviolet light (see, for example, Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] On the other hand, in a paint containing photocatalytic titanium oxide, the deterioration of the coating film is promoted by the redox action of the titanium oxide upon receiving light, and the color of the coating film changes (including fading) from the intended color.

[0005] When the pigment volume concentration (PVC) of the paint is increased, the amount of the resin component in the coating film decreases, and the exposed photocatalyst that is not sufficiently covered by the resin component increases, so that the antibacterial and antiviral properties can be improved. However, in that case, since the amount of the resin component in the coating film decreases, cracks are likely to occur in the coating film during film formation. Cracks not only cause problems in the appearance of the coating film but also reduce the adhesion of the coating film to the object to be coated. When the adhesion of the coating film to the object to be coated decreases, there is also a risk that the coating film in the portion where the adhesion has decreased will peel off, and the photocatalytic effect cannot be obtained in the portion where the coating film has peeled off.

[0006] Therefore, an object of the present invention is to provide a paint composition capable of forming a coating film having antiviral and antibacterial properties, discoloration resistance to photo-degradation of a coating film containing photocatalytic titanium oxide (hereinafter referred to as "photo-degradation discoloration resistance"), and crack resistance.

[0007] Another object of the present invention is to provide a coating film having antiviral and antibacterial properties, photo-degradation discoloration resistance, and crack resistance.

[0008] Another object of the present invention is to provide an article having a coating film having antiviral and antibacterial properties, photo-degradation discoloration resistance, and crack resistance.

Means for Solving the Problems

[0009] The paint composition according to the present invention is an acrylic resin emulsion, photocatalytic titanium oxide, a pigment, and is a paint composition, wherein the proportion of aromatic vinyl monomer units in the acrylic resin of the acrylic resin emulsion is 0 to 52% by mass, the photocatalytic titanium oxide includes metal-supported anatase-type titanium oxide, the content of the metal-supported anatase-type titanium oxide is 0.05 to 2.90 parts by mass with respect to 100 parts by mass of the total solid content of the paint composition, the pigment volume concentration (PVC) of the pigment is 35 to 65%. Thus, it is possible to form a coating film having antiviral and antibacterial properties, discoloration resistance to photo-degradation of a coating film containing photocatalytic titanium oxide, and crack resistance.

[0010] In one embodiment of the paint composition according to the present invention, the acrylic resin does not contain the aromatic vinyl monomer units.

[0011] In one embodiment of the paint composition according to the present invention, the proportion of the aromatic vinyl monomer units is 0 to 16% by mass of the total solid content of the paint composition.

[0012] In one embodiment of the paint composition according to the present invention, the photocatalytic titanium oxide further includes metal-supported rutile titanium oxide.

[0013] The coating film according to the present invention is a coating film using any of the above paint compositions. Thereby, it has antiviral and antibacterial properties, discoloration resistance against light deterioration of the coating film containing photocatalytic titanium oxide, and crack resistance.

[0014] The article according to the present invention is an article having the above coating film. Thereby, it has antiviral and antibacterial properties, light deterioration discoloration resistance, and crack resistance.

Effects of the Invention

[0015] According to the present invention, it is possible to provide a paint composition capable of forming a coating film having antiviral and antibacterial properties, light deterioration discoloration resistance, and crack resistance. According to the present invention, it is possible to provide a coating film having antiviral and antibacterial properties, light deterioration discoloration resistance, and crack resistance. According to the present invention, it is possible to provide an article having a coating film having antiviral and antibacterial properties, light deterioration discoloration resistance, and crack resistance.

Modes for Carrying Out the Invention

[0016] Hereinafter, embodiments of the present invention will be described. These descriptions are for the purpose of exemplifying the present invention and do not limit the present invention in any way.

[0017] In the present invention, two or more embodiments can be arbitrarily combined.

[0018] In the present invention, paint and paint composition can be used interchangeably.

[0019] In the present invention, the term "solid content" is a concept including solid content and non-volatile content.

[0020] In this specification, unless otherwise specified, a numerical range is intended to include the upper and lower limits of that range. For example, 0 to 52% means 0% or more and 52% or less.

[0021] In this specification, (meth)acrylic acid means one or more selected from the group consisting of acrylic acid and methacrylic acid. In this specification, (meth)acrylonitrile means one or more selected from the group consisting of acrylonitrile and methacrylonitrile. In this specification, (meth)acrylamide means one or more selected from the group consisting of acrylamide and methacrylamide.

[0022] In this specification, an aromatic vinyl monomer unit means a structural unit formed by polymerizing an aromatic vinyl monomer. In this specification, a (meth)acrylonitrile monomer unit means a structural unit formed by polymerizing a (meth)acrylonitrile monomer. In this specification, a polyfunctional monomer unit means a structural unit formed by polymerizing a polyfunctional monomer. A polyfunctional monomer is a monomer having two or more functional groups capable of forming a crosslinked structure during or after polymerization by heating or irradiation with energy rays. In this specification, a (meth)acrylate monomer unit means a structural unit formed by polymerizing a (meth)acrylate monomer. In this specification, a carboxy group-containing monomer unit means a structural unit formed by polymerizing a monomer having a carboxy group.

[0023] In this specification, in an acrylic resin produced by copolymerizing two or more monomers, the proportion of the structural unit formed by polymerizing a certain monomer in the acrylic resin usually coincides with the ratio (charge ratio) of the mass of the certain monomer to the total mass of the monomers, reactive emulsifier, and polymerization initiator used in the polymerization of the acrylic resin, unless otherwise specified.

[0024] In this specification, titanium oxide having an anatase crystal structure is referred to as anatase-type titanium oxide, and titanium oxide having a rutile crystal structure is referred to as rutile-type titanium oxide.

[0025] In this specification, the term "titanium oxide" other than photocatalytic titanium oxide, metal-supported anatase titanium oxide, metal-supported rutile titanium oxide, and metal-supported titanium oxide refers to titanium oxide as a pigment, not photocatalytic titanium oxide.

[0026] (Paint composition) The paint composition according to the present invention is an acrylic resin emulsion, photocatalytic titanium oxide, a pigment, and is a paint composition containing the proportion of aromatic vinyl monomer units in the acrylic resin of the acrylic resin emulsion is 0 to 52% by mass, the photocatalytic titanium oxide includes metal-supported anatase titanium oxide, the content of the metal-supported anatase titanium oxide is 0.05 to 2.90 parts by mass with respect to 100 parts by mass of the total solid content of the paint composition, the pigment volume concentration (PVC) of the pigment is 35 to 65%, and is a paint composition.

[0027] Hereinafter, the acrylic resin emulsion, photocatalytic titanium oxide, and pigment of the paint composition according to the present invention will be described.

[0028] ·Acrylic resin emulsion The acrylic resin emulsion is a component containing an acrylic resin which is a film-forming component.

[0029] The proportion of aromatic vinyl monomer units in the acrylic resin of the acrylic resin emulsion is 0 to 52% by mass. By setting the proportion of aromatic vinyl monomer units to 0 to 52% by mass, the discoloration resistance of the paint film containing photocatalytic titanium oxide to light deterioration is improved.

[0030] Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, styrenesulfonic acid, butoxystyrene, vinylnaphthalene, and the like. In one embodiment, the aromatic vinyl monomer is styrene.

[0031] The proportion of the aromatic vinyl monomer unit in the acrylic resin is 0 to 52% by mass. When the proportion of the aromatic vinyl monomer unit in the acrylic resin exceeds 52% by mass based on the total mass of the acrylic resin, the discoloration resistance against photo-degradation of the coating film containing the photocatalytic titanium oxide cannot be improved. In one embodiment, the proportion of the aromatic vinyl monomer unit in the acrylic resin is 0% by mass or more, 10.0% by mass or more, 20.0% by mass or more, 30.0% by mass or more, or 40.0% by mass or more. In another embodiment, the proportion of the aromatic vinyl monomer unit in the acrylic resin is 52.0% by mass or less, 50.0% by mass or less, 40.0% by mass or less, 30.0% by mass or less, 25.0% by mass or less, 21.0% by mass or less, 20.0% by mass or less, or 10.0% by mass or less.

[0032] When two or more kinds of acrylic resins having different proportions of the aromatic vinyl monomer unit are used in combination, the weighted average value of the proportion of the aromatic vinyl monomer unit may be 0 to 52% by mass.

[0033] In one embodiment of the coating composition according to the present invention, the acrylic resin does not contain the aromatic vinyl monomer unit, that is, the proportion of the aromatic vinyl monomer unit in the acrylic resin is 0% by mass.

[0034] As long as the proportion of the aromatic vinyl monomer unit in the acrylic resin satisfies 0 to 52% by mass, the proportion of the aromatic vinyl monomer unit with respect to the total solid content of the coating composition may be adjusted as appropriate. The proportion of the aromatic vinyl monomer unit is, for example, 0 to 20% by mass of the total solid content of the coating composition. In one embodiment, the proportion of the aromatic vinyl monomer unit is 0% by mass or more, 1.0% by mass or more, 2.0% by mass or more, 3.0% by mass or more, 4.0% by mass or more, 5.0% by mass or more, 6.0% by mass or more, 7.0% by mass or more, 8.0% by mass or more, 9.0% by mass or more, 10.0% by mass or more, or 15.0% by mass or more of the total solid content of the coating composition. In another embodiment, the proportion of the aromatic vinyl monomer unit is 20.0% by mass or less, 16.0% by mass or less, 15.0% by mass or less, 10.0% by mass or less, 9.0% by mass or less, 8.0% by mass or less, 7.0% by mass or less, 6.0% by mass or less, 5.0% by mass or less, 4.0% by mass or less, 3.0% by mass or less, 2.0% by mass or less, or 1.0% by mass or less of the total solid content of the coating composition.

[0035] In one embodiment of the coating composition according to the present invention, the proportion of the aromatic vinyl monomer unit is 0 to 16% by mass of the total solid content of the coating composition.

[0036] Examples of other monomers that can constitute the acrylic resin include (meth)acrylic acid ester monomer units, carboxy group-containing monomers, polyfunctional monomers, (meth)acrylonitrile monomers, (meth)acrylamide monomers, vinyl chloride-based monomers, vinyl acetate-based monomers, vinylamine-based monomers, vinylamide-based monomers, (meth)acrylic acid derivative monomers, unsaturated carboxylic acid anhydride monomers, maleimide derivative monomers, diene-based monomers, and the like. The acrylic resin may contain monomer units derived from one or more of these monomers. In one embodiment, the acrylic resin contains monomer units derived from one or more selected from the group consisting of aromatic vinyl monomers, (meth)acrylic acid ester monomer units, carboxy group-containing monomers, polyfunctional monomers, (meth)acrylonitrile monomer units, vinyl chloride-based monomer units, vinyl acetate-based monomer units, vinylamine-based monomer units, vinylamide-based monomer units, (meth)acrylic acid derivatives, unsaturated carboxylic acid anhydride monomer units, maleimide derivative monomer units, and diene-based monomers. In another embodiment, the acrylic resin contains monomer units derived from one or more selected from the group consisting of aromatic vinyl monomers, (meth)acrylic acid ester monomer units, carboxy group-containing monomers, polyfunctional monomers, and (meth)acrylonitrile monomer units. In yet another embodiment, the acrylic resin contains monomer units derived from one or more selected from the group consisting of aromatic vinyl monomers and (meth)acrylic acid ester monomer units. In yet another embodiment, the acrylic resin contains (meth)acrylic acid ester monomer units. In yet another embodiment, the acrylic resin contains (meth)acrylic acid ester monomer units and further contains monomer units derived from one or more selected from the group consisting of carboxy group-containing monomers, polyfunctional monomers, (meth)acrylonitrile monomer units, vinyl chloride-based monomer units, vinyl acetate-based monomer units, vinylamine-based monomer units, vinylamide-based monomer units, (meth)acrylic acid derivatives, unsaturated carboxylic acid anhydride monomer units, maleimide derivative monomer units, and diene-based monomers. In yet another embodiment, it contains only (meth)acrylic acid ester monomer units.

[0037] (Meth)acrylic acid esters monomers include, for example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, isopropyl acrylate, isopropyl methacrylate, propyl acrylate, propyl methacrylate, isobutyl acrylate, isobutyl methacrylate, butyl acrylate, butyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, sec-butyl acrylate, sec-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, pentyl acrylate, pentyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, hexyl acrylate, hexyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, octyl acrylate, octyl methacrylate, lauryl acrylate, lauryl methacrylate, stearyl acrylate, stearyl methacrylate, myristyl acrylate, myristyl methacrylate, palmityl acrylate, palmityl methacrylate, glycidyl acrylate, glycidyl methacrylate, trifluoroethyl acrylate, trifluoroethyl methacrylate, isopentyl acrylate, isopentyl methacrylate, octyl acrylate, octyl methacrylate, decyl acrylate, decyl methacrylate, dodecyl acrylate, dodecyl methacrylate, dodecenyl acrylate, dodecenyl methacrylate, octadecyl acrylate, octadecyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, 4-tert-butylcyclohexyl acrylate, 4-tert-butylcyclohexyl methacrylate, phenyl acrylate, phenyl methacrylate, isobornyl acrylate, isobornyl methacrylate, benzyl acrylate, benzyl methacrylate, 2-phenylethyl acrylate, 2-phenylethyl methacrylate, 2-methoxyethyl acrylate, 2-methoxyethyl methacrylate, 4-methoxybutyl acrylate, 4-methoxybutyl methacrylate, and the like.

[0038] The proportion of the (meth)acrylic acid ester monomer unit in the acrylic resin may be adjusted as appropriate, for example, it is 5 to 100% by mass. In one embodiment, the proportion of the (meth)acrylic acid ester monomer unit in the acrylic resin is 5% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, or 100% by mass. In another embodiment, the proportion of the (meth)acrylic acid ester monomer unit in the acrylic resin is 100% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, or 10% by mass or less.

[0039] Examples of the carboxy group-containing monomer include acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, and the like.

[0040] The proportion of the carboxy group-containing monomer unit in the acrylic resin may be adjusted as appropriate, for example, it is 0 to 95% by mass. In one embodiment, the proportion of the carboxy group-containing monomer unit in the acrylic resin is 0% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, or 95% by mass. In another embodiment, the proportion of the carboxy group-containing monomer unit in the acrylic resin is 95% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, 10% by mass or less, or 0% by mass.

[0041] Examples of the polyfunctional monomer include divinylbenzene, ethylene dimethacrylate, diethylene glycol dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, 1,3-butylene glycol diacrylate, allyl methacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, allyl glycidyl ether, glycidyl methacrylate, and the like.

[0042] The proportion of the polyfunctional monomer unit in the acrylic resin may be adjusted as appropriate. For example, it is 0 to 95% by mass. In one embodiment, the proportion of the polyfunctional monomer unit in the acrylic resin is 0% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, or 95% by mass. In another embodiment, the proportion of the polyfunctional monomer unit in the acrylic resin is 95% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, 10% by mass or less, or 0% by mass.

[0043] Examples of the (meth)acrylonitrile monomer include acrylonitrile, methacrylonitrile, and other (meth)acrylonitrile derivatives.

[0044] The proportion of the (meth)acrylonitrile monomer unit in the acrylic resin may be adjusted as appropriate. For example, it is 0 to 95% by mass. In one embodiment, the proportion of the (meth)acrylonitrile monomer unit in the acrylic resin is 0% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, or 95% by mass. In another embodiment, the proportion of the (meth)acrylonitrile monomer unit in the acrylic resin is 95% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, 10% by mass or less, or 0% by mass.

[0045] Examples of the (meth)acrylamide monomer include acrylamide, methacrylamide, and diacetone acrylamide.

[0046] The proportion of the (meth)acrylamide monomer unit in the acrylic resin may be adjusted as appropriate. For example, it is 0 to 95% by mass. In one embodiment, the proportion of the (meth)acrylamide monomer unit in the acrylic resin is 0% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, or 95% by mass. In another embodiment, the proportion of the (meth)acrylamide monomer unit in the acrylic resin is 95% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, 10% by mass or less, or 0% by mass.

[0047] Examples of the vinyl chloride monomer include vinyl chloride and vinylidene chloride.

[0048] Examples of the vinyl acetate monomer include vinyl acetate.

[0049] Examples of the vinylamine monomer include vinylamine.

[0050] Examples of the vinylamide monomer include N-vinylformamide and N-vinylacetamide.

[0051] Examples of the unsaturated carboxylic acid anhydride monomer include maleic anhydride.

[0052] Examples of the diene monomer include 1,3-butadiene and isoprene.

[0053] The proportions of vinyl chloride monomer units, vinyl acetate monomer units, vinylamine monomer units, vinylamide monomer units, unsaturated carboxylic anhydride monomer units, and diene monomer units in the acrylic resin are, for example, each 0 to 95% by mass. In one embodiment, the proportions of vinyl chloride monomer units, vinyl acetate monomer units, vinylamine monomer units, vinylamide monomer units, unsaturated carboxylic anhydride monomer units, and diene monomer units in the acrylic resin are each 0% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, or 95% by mass. In another embodiment, the proportions of vinyl chloride monomer units, vinyl acetate monomer units, vinylamine monomer units, vinylamide monomer units, unsaturated carboxylic anhydride monomer units, and diene monomer units in the acrylic resin are each 95% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, 10% by mass or less, or 0% by mass.

[0054] The above-mentioned monomers of the acrylic resin may each be used alone or in combination of two or more.

[0055] The glass transition temperature (Tg) of the acrylic resin may be adjusted as appropriate, and is, for example, -50 to 50°C. In one embodiment, the Tg of the acrylic resin is -50°C or higher, -40°C or higher, -30°C or higher, -20°C or higher, -10°C or higher, 0°C or higher, 10°C or higher, 20°C or higher, 30°C or higher, or 40°C or higher. In another embodiment, the Tg of the acrylic resin is 50°C or lower, 40°C or lower, 30°C or lower, 20°C or lower, 10°C or lower, 0°C or lower, -10°C or lower, -20°C or lower, -30°C or lower, or -40°C or lower. In yet another embodiment, the Tg of the acrylic resin is -35 to 30°C.

[0056] In the present invention, the Tg of the acrylic resin is calculated from the following formula. 1 / Tg = M1 / T1 + M2 / T2 + ··· M n / Tn wherein, M1, M2, ··· M n represents the mass % of each monomer, and T1, T2, ··· T n represents the Tg (absolute temperature) of the homopolymer of each monomer. The mass % of each monomer is determined from the compounding amount (parts by mass) of each monomer × 100 / total compounding amount (parts by mass) of the monomers.

[0057] The molecular weight of the acrylic resin may be adjusted as appropriate. For example, the number average molecular weight is 5,000 to 300,000. In one embodiment, the number average molecular weight of the acrylic resin is 5,000 or more, 10,000 or more, 50,000 or more, 100,000 or more, 150,000 or more, 200,000 or more, or 250,000 or more. In another embodiment, the number average molecular weight of the acrylic resin is 300,000 or less, 250,000 or less, 200,000 or less, 150,000 or less, 100,000 or less, 50,000 or less, or 10,000 or less.

[0058] The number average molecular weight Mn is a value calculated from the molecular weight in terms of standard polystyrene measured by gel permeation chromatography (GPC) method using tetrahydrofuran or chloroform as the measurement solvent.

[0059] The acrylic resin may be used alone or in combination of two or more.

[0060] The amount of the acrylic resin (solid content) in the coating composition is not particularly limited as long as it satisfies the predetermined content ranges of the metal-supported anatase-type titanium oxide and the pigment PVC described below, and may be adjusted as appropriate. The amount of the acrylic resin (solid content) in the coating composition is, for example, 5 to 30 parts by mass with respect to 100 parts by mass of the total solid content of the coating composition. In one embodiment, the amount of the acrylic resin (solid content) is 5 parts by mass or more, 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, or 25 parts by mass or more with respect to 100 parts by mass of the total solid content of the coating composition. In another embodiment, the amount of the acrylic resin (solid content) is 30 parts by mass or less, 25 parts by mass or less, 20 parts by mass or less, 15 parts by mass or less, 10 parts by mass or less, or 5 parts by mass or less with respect to 100 parts by mass of the total solid content of the coating composition.

[0061] The acrylic resin emulsion may contain, in addition to the acrylic resin, a solvent, a polymerization initiator, an emulsifier, a chain transfer agent, and the like. These components may be used individually or in combination of two or more thereof.

[0062] Examples of the solvent include water such as deionized water, ion-exchanged water, pure water, distilled water, purified water, and tap water; alcohols such as methanol, ethanol, 2-propanol, and 1-butanol; esters such as ethyl acetate, butyl acetate, isobutyl acetate, ethyl propionate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, and propylene glycol monoethyl ether acetate; ethers such as diethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, dioxane, and tetrahydrofuran (THF); glycols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butylene glycol, pentamethylene glycol, and 1,3-octylene glycol; amides such as formamide, N-methylformamide, dimethylformamide (DMF), dimethylacetamide, dimethyl sulfoxide (DMSO), and N-methylpyrrolidone (NMP); ketones such as acetone, methyl ethyl ketone (MEK), methyl propyl ketone, methyl isobutyl ketone, acetylacetone, and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, mesitylene, and dodecylbenzene; and halogenated solvents such as chloroform and dichloromethane. In one embodiment, the solvent contains water. In another embodiment, the solvent is water.

[0063] Examples of the polymerization initiator include ammonium persulfate and potassium persulfate. In addition, as the polymerization initiator, for example, the polymerization initiators described in Japanese Patent No. 6058843, Japanese Patent Application Laid-Open No. 01-098652, etc. may also be used.

[0064] Examples of the emulsifier include sodium dodecylbenzenesulfonate, sodium lauryl sulfate, ammonium lauryl sulfate, sodium alkyl diphenyl ether disulfonate, and polyoxyethylene alkyl ester. In addition, as the emulsifier, for example, the emulsifiers described in Japanese Patent No. 6058843, Japanese Patent Application Laid-Open No. 01-098652, etc. may also be used.

[0065] Examples of the chain transfer agent include lauryl mercaptan, n-butyl mercaptan, t-butyl mercaptan, dodecyl mercaptan, octyl mercaptan, 2-ethylhexyl thioglycolate, 2-methyl-5-t-butyl thiophenol, carbon tetrabromide, α-methylstyrene dimer, and the like. In addition, as the chain transfer agent, for example, the chain transfer agents described in JP-A-2015-193779 may also be used.

[0066] The method for preparing the acrylic resin emulsion is not particularly limited as long as the proportion of the aromatic vinyl monomer unit in the acrylic resin is 0 to 50% by mass, and a known preparation method can be used. Examples of the method for preparing the acrylic resin emulsion include the method for preparing the aqueous emulsion (A) described in JP-A-2015-193779.

[0067] An example of the method for preparing the acrylic resin emulsion is as follows. Deionized water and an emulsifier are placed in a glass reactor equipped with a dropping funnel, a reflux condenser, a stirrer, and a thermometer, and the temperature of the contents is set to 85°C. A pre-emulsion composed of a monomer such as (meth)acrylate ester, an emulsifier, and deionized water and a polymerization initiator are dropped into the mixture from the dropping funnel, and the mixture is reacted. The reaction temperature is maintained at 85°C. After the dropping is completed, the product is maintained at 85°C for 3 hours. Then the product is cooled to 30°C and taken out from the reactor to obtain an acrylic resin emulsion.

[0068] The coating composition may contain a resin emulsion other than the acrylic resin emulsion. Examples of the resin emulsion other than the acrylic resin emulsion include synthetic resin emulsions composed of resin components such as vinyl acetate resin emulsion, vinyl chloride resin emulsion, epoxy resin emulsion, urethane resin emulsion, acrylic silicone resin emulsion, fluororesin emulsion, and composite systems thereof. The resin emulsion other than the acrylic resin emulsion may be used alone or in combination of two or more.

[0069] In one embodiment, the resin emulsion other than the acrylic resin emulsion is at least one selected from the group consisting of a vinyl acetate resin emulsion and a urethane resin emulsion.

[0070] The amount of the resin (solid content) other than the acrylic resin in the coating composition is not particularly limited as long as it satisfies the predetermined content range of the metal-supported anatase-type titanium oxide and the predetermined content range of the PVC of the pigment, and may be adjusted as appropriate. The amount of the resin (solid content) other than the acrylic resin in the coating composition is, for example, 0 to 35 parts by mass with respect to 100 parts by mass of the total solid content of the coating composition.

[0071] · Photocatalytic titanium oxide The photocatalytic titanium oxide is a component that imparts antibacterial or antiviral properties to the coating film using the coating composition of the present invention. In the present invention, the photocatalytic titanium oxide is not included in the pigments described later.

[0072] The photocatalytic titanium oxide includes metal-supported anatase-type titanium oxide. As the existence form of the metal component contained in the metal-supported anatase-type titanium oxide, a state in which a part of the metal component is dispersed alone on the premise that it is in contact with the anatase-type titanium oxide can be mentioned. The crystal structure of the photocatalytic titanium oxide can be identified by, for example, powder X-ray diffraction.

[0073] As the metal supported by the metal-supported anatase-type titanium oxide, the metal of known metal-supported titanium oxide can be selected and used. Examples of the metal supported by the metal-supported anatase-type titanium oxide include metals such as vanadium V, iron Fe, cobalt Co, nickel Ni, copper Cu, zinc Zn, ruthenium Ru, rhodium Rh, palladium Pd, silver Ag, platinum Pt, and gold Au, silver compounds such as silver oxide (Ag2O), and copper compounds such as Cu(OH)2, Cu2O, and CuO. Such metals or metal compounds may be used alone or in combination of two or more.

[0074] In one embodiment, the metal supported on the metal-supported anatase-type titanium oxide is at least one selected from the group consisting of silver, copper, silver compounds, and copper compounds. In another embodiment, the metal supported on the metal-supported anatase-type titanium oxide is at least one selected from the group consisting of silver, copper, silver oxide (Ag2O), Cu(OH)2, Cu2O, and CuO.

[0075] Commercially available products may be used for the metal-supported anatase-type titanium oxide. Examples of commercially available products of the metal-supported anatase-type titanium oxide include ST series such as product names ST-01, ST-21, ST-31, and ST-41 manufactured by Ishihara Sangyo Co., Ltd.; product names AMT-100 and AMT-600 manufactured by Teika Co., Ltd.; product names SSP-N, SSP-20, and SPP-M manufactured by Sakai Chemical Industry Co., Ltd., and the like.

[0076] The metal-supported anatase-type titanium oxide may be used alone or in combination of two or more.

[0077] The proportion of the metal-supported anatase-type titanium oxide in the photocatalytic-type titanium oxide is, for example, 0.5 to 100% by mass. In one embodiment, the proportion of the metal-supported anatase-type titanium oxide in the photocatalytic-type titanium oxide is 0.5% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, or 90% by mass or more. In another embodiment, the proportion of the metal-supported anatase-type titanium oxide in the photocatalytic-type titanium oxide is 100% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, or 10% by mass or less. In a preferred embodiment, the proportion of the metal-supported anatase-type titanium oxide in the photocatalytic-type titanium oxide is 10 to 100% by mass.

[0078] The content of the metal-supported anatase-type titanium oxide is 0.05 to 2.90 parts by mass with respect to 100 parts by mass of the total solid content of the coating composition. By being 0.05 parts by mass or more, the antibacterial or antiviral property of the coating film is enhanced, and by being 2.90 parts by mass or less, the discoloration resistance against photo-degradation of the coating film containing the photocatalytic titanium oxide can be suppressed.

[0079] In addition to the metal-supported anatase-type titanium oxide, the photocatalytic titanium oxide may further contain a metal-supported rutile-type titanium oxide. Examples of the existence form of the metal component contained in the metal-supported rutile-type titanium oxide include a state in which the metal component is in contact with the rutile-type titanium oxide.

[0080] Examples of the metal supported by the metal-supported rutile-type titanium oxide include the metals exemplified as the metals supported by the metal-supported anatase-type titanium oxide. The supported metal or metal compound may be used alone or in combination of two or more.

[0081] In one embodiment, the metal supported by the metal-supported rutile-type titanium oxide is one or more selected from the group consisting of silver, copper, silver compounds and copper compounds. In another embodiment, the metal supported by the metal-supported rutile-type titanium oxide is one or more selected from the group consisting of silver, copper, silver oxide (Ag2O), Cu(OH)2, Cu2O and CuO. In still another embodiment, the metal supported by the metal-supported rutile-type titanium oxide is at least one divalent copper compound.

[0082] In one embodiment, the copper compound supported by the metal-supported rutile-type titanium oxide is a copper compound that is insoluble or hardly soluble in water. In another embodiment, the copper compound supported by the metal-supported rutile-type titanium oxide is a copper compound having a solubility product smaller than 1.5×10 -10 The solubility product is determined based on the "Fourth Edition Chemical Experiment Handbook" published by Gihodo Publishing Co., Ltd. in 1984 by the Editorial Committee of the Chemical Experiment Handbook.

[0083] In addition, as the metal-supported rutile-type titanium oxide, for example, the metal-supported rutile-type titanium oxide described in Patent Document 1 may be used.

[0084] As the metal-supported rutile-type titanium oxide, commercially available products may be used. Examples of commercially available products of metal-supported rutile-type titanium oxide include, for example, Photo Peek MPT-623 manufactured by Ishihara Sangyo Co., Ltd.; trade names STR-100C and STR-100W manufactured by Sakai Chemical Industry Co., Ltd.

[0085] The metal-supported rutile-type titanium oxide may be used alone or in combination of two or more.

[0086] When the metal-supported rutile-type titanium oxide is included, the proportion of the metal-supported rutile-type titanium oxide in the photocatalytic titanium oxide is, for example, 1 to 99.5% by mass. In one embodiment, when the metal-supported rutile-type titanium oxide is included, the proportion of the metal-supported rutile-type titanium oxide in the photocatalytic titanium oxide is 1% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more or 90% by mass or more. In another embodiment, when the metal-supported rutile-type titanium oxide is included, the proportion of the metal-supported rutile-type titanium oxide in the photocatalytic titanium oxide is 99.5% by mass or less, 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less or 10% by mass or less. In a preferred embodiment, the proportion of the metal-supported rutile-type titanium oxide in the photocatalytic titanium oxide is 0 to 90% by mass.

[0087] In one embodiment of the paint composition according to the present invention, the photocatalytic titanium oxide further contains a metal-supported rutile-type titanium oxide.

[0088] The content of the photocatalytic titanium oxide with respect to 100 parts by mass of the total solid content of the coating composition is, for example, 0.05 to 2.85 parts by mass. In one embodiment, the content of the photocatalytic titanium oxide with respect to 100 parts by mass of the total solid content of the coating composition is 0.1 part by mass or more, 0.50 part by mass or more, 1.00 part by mass or more, 1.10 part by mass or more, 1.20 part by mass or more, 1.30 part by mass or more, 1.40 part by mass or more, 1.50 part by mass or more, 1.60 part by mass or more, 1.70 part by mass or more, 1.80 part by mass or more, 1.90 part by mass or more, 2.00 part by mass or more, 2.10 part by mass or more, 2.20 part by mass or more, 2.30 part by mass or more, 2.40 part by mass or more, 2.50 part by mass or more, 2.60 part by mass or more, 2.70 part by mass or more or 2.80 part by mass or more. In another embodiment, the content of the photocatalytic titanium oxide with respect to 100 parts by mass of the total solid content of the coating composition is 2.85 parts by mass or less, 2.80 parts by mass or less, 2.70 parts by mass or less, 2.60 parts by mass or less, 2.50 parts by mass or less, 2.40 parts by mass or less, 2.30 parts by mass or less, 2.20 parts by mass or less, 2.10 parts by mass or less, 2.00 parts by mass or less, 1.90 parts by mass or less, 1.80 parts by mass or less, 1.70 parts by mass or less, 1.60 parts by mass or less, 1.50 parts by mass or less, 1.40 parts by mass or less, 1.30 parts by mass or less, 1.20 parts by mass or less, 1.10 parts by mass or less, 1.00 parts by mass or less or 0.50 parts by mass or less.

[0089] · Pigment The pigment is a component that imparts design properties to the coating film using the coating composition of the present invention.

[0090] The pigment is not particularly limited, and pigments of known coating compositions can be used. Examples of the pigment include coloring pigments, extender pigments, matting agents, etc. Therefore, in the present invention, the term "pigment" is a concept including coloring pigments, extender pigments, and matting agents.

[0091] Examples of the coloring pigment include organic coloring pigments, inorganic coloring pigments, etc.

[0092] Examples of organic coloring pigments include azo lake pigments, insoluble azo pigments, condensed azo pigments, phthalocyanine pigments, indigo pigments, perinone pigments, perylene pigments, phthalone pigments, dioxazine pigments, quinacridone pigments, isoindolinone pigments, metal complex pigments, and the like.

[0093] Examples of inorganic coloring pigments include yellow iron oxide, red iron oxide, carbon black, titanium dioxide, and the like.

[0094] The color of the coloring pigment is not particularly limited, and known colors including white can be adopted.

[0095] The coloring pigment may be used alone or in combination of two or more.

[0096] Examples of extender pigments include barite powder, precipitated barium sulfate, barium carbonate, gypsum, clay, white carbon, magnesium carbonate, alumina white, and gloss white.

[0097] The matting agent is a component that contributes to an increase in the surface area of the coating film. The larger the surface area of the coating film, the easier it is for the coating film to absorb light, and the easier it is for the effect of photocatalytic titanium dioxide to be exhibited.

[0098] Examples of matting agents include inorganic matting agents such as talc, silica, calcium carbonate, barium sulfate, feldspar, wollastonite, diatomaceous earth, zeolite, and nepheline syenite, and organic matting agents composed of organic fine particles.

[0099] The matting agent preferably has a particulate form, more preferably fine particles having an average particle diameter of 0.1 to 100 μm. When the average particle diameter is 0.1 μm or more, the effect of increasing the surface area of the coating film can be easily obtained. When the average particle diameter is 100 μm or less, a good aesthetic feeling of the coating film can be easily obtained.

[0100] Further, the matting agent may be an inorganic or organic porous pigment. The preferred average particle diameter of the porous pigment is as described above. The diameter of the pores (pore diameter) of the porous pigment is, for example, 0.1 to 50 nm. In a preferred embodiment, the pore diameter of the porous pigment is 0.2 to 50 nm, and in another preferred embodiment, the pore diameter of the porous pigment is 0.2 to 10 nm.

[0101] Examples of the inorganic porous pigment include diatomaceous earth, zeolite, activated carbon, activated alumina, silica gel, hydroxyapatite, zirconium phosphate, titanium phosphate, potassium titanate, hydrated bismuth hydroxide, hydrated zirconium hydroxide, hydrotalcite, mesoporous silica, and the like. In one embodiment, the inorganic porous pigment is one or more selected from the group consisting of diatomaceous earth and zeolite.

[0102] In one embodiment, the pigment contains an inorganic porous pigment.

[0103] The amount of the porous pigment in the pigment may be adjusted as appropriate. For example, it is 0.1 to 50 parts by mass, or 2.0 to 22 parts by mass, based on 100 parts by mass of the pigment.

[0104] In one embodiment, the pigment contains an inorganic porous pigment, and the amount of the inorganic porous pigment is 0.1 to 50 parts by mass based on 100 parts by mass of the pigment.

[0105] In the present invention, the pigment volume concentration (PVC) represents the ratio of the volume of the pigment to the total solid volume of the resin component, the photocatalytic titanium oxide, and the pigment. In the present invention, the PVC is 35 to 65%. As described above, even if the amount of the photocatalyst is constant, increasing the PVC reduces the amount of the resin component in the coating film, and the amount of the photocatalyst exposed without being sufficiently covered by the resin component increases, so that the antibacterial property and the antiviral property can be improved. However, in that case, the crack resistance of the coating film decreases. Conversely, when the PVC decreases, the crack resistance of the coating film increases, but since the photocatalyst is covered by the resin component and the exposed photocatalyst decreases, the antiviral property and the antibacterial property of the coating film decrease. In contrast, in the present invention, by setting the PVC to 35 to 65%, the antiviral property and the antibacterial property of the coating film and the crack resistance can be enhanced.

[0106] In one embodiment, the PVC is 35.0% or more, 40.0% or more, 45.0% or more, 46.0% or more, 47.0% or more, 48.0% or more, 49.0% or more, 50.0% or more, 51.0% or more, 52.0% or more, 53.0% or more, 54.0% or more, 55.0% or more, or 60.0% or more. In another embodiment, the PVC is 65.0% or less, 60.0% or less, 55.0% or less, 54.0% or less, 53.0% or less, 52.0% or less, 51.0% or less, 50.0% or less, 49.0% or less, 48.0% or less, 47.0% or less, 46.0% or less, 45.0% or less, or 40.0% or less.

[0107] PVC can be determined from the density of the solid content and the mass of the solid content of, for example, the resin component, the photocatalytic titanium oxide, and the pigment to obtain their respective volumes, and then calculated from the volume of the pigment × 100 / (the sum of the volume of the resin component, the volume of the photocatalytic titanium oxide, and the volume of the pigment). The density (specific gravity) of the resin component is measured, for example, as follows: Measure the specific gravity of the emulsion solution with a specific gravity cup. Next, measure the emulsion NV. Calculate the specific gravity obtained by removing the proportion of water in the emulsion solution from the specific gravity of the emulsion solution measured with the specific gravity cup, and use this as the emulsion specific gravity. The emulsion NV is measured under the conditions of sample amount: 1.0 ± 0.2 g, drying temperature: 105 ± 2 °C, and drying time: 60 minutes in accordance with JIS K 6833-1:2008. The emulsion specific gravity is measured in accordance with JIS K 6833-1:2008.

[0108] Alternatively, PVC may be determined directly from the volumes of the solid contents of the resin component, the photocatalytic titanium oxide, and the pigment, and then calculated from the volume of the pigment × 100 / (the sum of the volume of the resin component, the volume of the photocatalytic titanium oxide, and the volume of the pigment).

[0109] · Other components The coating composition may optionally contain other components other than the acrylic resin emulsion, the photocatalytic titanium oxide, and the pigment. Examples of other components include aggregates, fibers, plasticizers, preservatives, fungicides, defoamers, viscosity modifiers, leveling agents, pigment dispersants, anti-settling agents, anti-dripping agents, ultraviolet absorbers, light stabilizers, antioxidants, antibacterial agents, adsorbents, etc. These components may be used alone or in combination of two or more.

[0110] The form of the coating composition is not particularly limited and may be a one-component type or a two-component type.

[0111] · Method for preparing the coating composition The method for preparing the coating composition is to mix the above-mentioned acrylic resin emulsion, photocatalytic titanium oxide, and pigment so that the content of metal-supported anatase-type titanium oxide and PVC are within a predetermined range, and a known method for preparing a coating composition can be used. For example, a coating composition can be prepared by mixing a resin emulsion, photocatalytic titanium oxide, and pigment, and optionally other components, using a disper, ball mill, S.G. mill, roll mill, planetary mixer, etc.

[0112] (Coating film) The coating film according to the present invention is a coating film using any of the above coating compositions.

[0113] The thickness of the coating film is not particularly limited and may be adjusted as appropriate. The thickness of the coating film (dry film thickness) is, for example, 10 μm to 200 μm.

[0114] The method for forming the coating film is not particularly limited, and a conventionally known coating method can be used. For example, it can be applied using an applicator, bar coater, brush, spray, roller, roll coater, curtain coater, etc. Alternatively, it can be applied by dipping in a paint bath.

[0115] The drying temperature after applying the coating composition may be appropriately adjusted according to the solvent, etc. For example, when drying in a short time such as 10 seconds to 30 minutes is required, it can be set to 30 to 200 °C, and 40 to 160 °C is preferable. When drying in a short time is required, a two-component curing reaction or an energy ray such as ultraviolet rays may be used. Also, when drying in a short time is not required, it may be dried at room temperature, for example.

[0116] (Article) The article according to the present invention is an article having any of the above coating films.

[0117] The article having the coating film is not particularly limited, and examples include vehicles such as automobiles, trains, buses, and taxis; vehicle tires; ships; aircraft such as airplanes and helicopters; exterior and interior surfaces of buildings or structures such as detached houses, apartment houses, office buildings, public facilities, commercial facilities, research facilities, military facilities, and tunnels, for example, wall surfaces, floor surfaces, ceilings, roofs, columns, signboards, electronic signboards (digital signage), doors, gates; bridges; vending machines; road signs; signals; streetlights; electric light display boards such as LED type, liquid crystal type, and electric bulb type; working machines, construction machines; stone tablets; tombstones; clothing; footwear such as shoes; rain gear such as umbrellas and raincoats; packaging materials; lenses such as glasses; mirrors, etc.

[0118] Examples of the base material of the article having the coating film include, for example, mortar, concrete, gypsum board, siding board, extruded board, slate board, asbestos cement board, fiber-reinforced cement board, calcium silicate board, ALC board, metal, wood, glass, ceramics, fired tile, porcelain tile, plastic board, wallpaper, synthetic resin, etc., or a coating film formed on these base materials, etc.

Examples

[0119] Hereinafter, the present invention will be described in more detail with reference to examples, but these examples are for the purpose of exemplifying the present invention and do not limit the present invention in any way.

[0120] The materials and devices used in the examples are as follows. Polyurethane resin emulsion: Trade name "Yukote (registered trademark) UX - 485" manufactured by Sanyo Chemical Industries, density 1.1 (g / cm 3 ) Vinyl acetate emulsion: Trade name "VINYBLAN (registered trademark) A68J1" manufactured by Nissin Chemical Industry Co., Ltd., density 1.1 (g / cm 3 ) Metal-supported anatase-type titanium oxide: Photocatalytic titanium oxide, anatase-type titanium oxide supporting silver oxide and copper oxide, density 4.1 (g / cm 3 ) Metal-supported rutile-type titanium oxide: Photocatalytic titanium oxide, solubility product is 1.5×10 -10Titanium oxide supporting a divalent copper compound smaller than, density 4.1 (g / cm 3 ) Titanium oxide: Coloring pigment, trade name "TIPAQUE (registered trademark) CR-97" manufactured by Ishihara Sangyo Co., Ltd., density 4.1 (g / cm 3 ) Calcium carbonate: Extender pigment, trade name "Special Rice SSS" manufactured by Maruo Calcium Co., Ltd., density 2.7 (g / cm 3 ) Diatomaceous earth: Inorganic porous pigment, trade name "Radiolite #100" manufactured by Maruto Co., Ltd., average particle diameter 12.8 μm, density 0.44 (g / cm 3 ) Zeolite: Inorganic porous pigment, trade name "Zeolam (registered trademark) F-9" manufactured by Tosoh Corporation, X-type zeolite, pore diameter 0.9 nm, density 1.8 (g / cm 3 ) Reactive emulsifier: Sodium alkyl diphenyl ether disulfonate, trade name "Pelec SS-H" manufactured by Kao Corporation, solid content 50% Polymerization initiator: Ammonium persulfate, 5.0% aqueous solution Substrate: Soda glass plate, dimensions 50 mm × 50 mm × 2 mm, trade name "Float Glass" manufactured by TP Giken Co., Ltd. Substrate: Mortar, dimensions 70 mm × 70 mm × 20 mm, trade name "Mortar" manufactured by TP Giken Co., Ltd., water:cement:sand = 0.6:1:2 (mass ratio) White fluorescent lamp: 20 W, trade name "Neo Line FL20SW" manufactured by Toshiba Lighting & Technology Corporation Ultraviolet cut filter: Acrylic resin plate manufactured by Nittobo Medical Co., Ltd., trade name "CLAREX (registered trademark) N-169" Illuminance meter: Digital illuminance meter, trade name "IM-5" manufactured by Topcon Corporation, used for antibacterial and antiviral property evaluation Accelerated weathering tester: Trade name "Super Xenon Weather Meter SX2-75" manufactured by Suga Test Instruments Co., Ltd. Color difference meter: Trade name "CR-400" manufactured by Konica Minolta Gypsum board: Trade name "Tiger Board" manufactured by Yoshino Gypsum Co., Ltd., corresponding to gypsum board GB-R of JIS A 6901 Substrate conditioner: Trade name "Field Pate" manufactured by Meiko

[0121] · Preparation of Acrylic Resin Emulsions 1 to 4 50.50 parts by mass of deionized water and 1.50 parts by mass of a reactive emulsifier were placed in a glass reactor equipped with a dropping funnel, a reflux condenser, a stirring device, and a thermometer, and the temperature of the contents was set to 85°C. The pre-emulsion and the polymerization initiator having the formulations shown in Table 1 were dropped into the mixture at a constant rate over 2 hours using the dropping funnel and reacted. After the dropping was completed, the product was maintained at 85°C for 3 hours. Then, the product was cooled to 30°C and taken out from the reactor to obtain acrylic resin emulsions 1 to 4 having a non-volatile content of 47% respectively. Since the reactive emulsifier and the polymerization initiator are incorporated into each acrylic resin, the ratio of the styrene unit in the acrylic resin is the ratio with respect to the mass of the acrylic resin containing the reactive emulsifier and the polymerization initiator.

[0122]

Table 1

[0123] (Examples 1 to 17 and Comparative Examples 1 to 6) Each component was mixed with the formulation (parts by mass) shown in Tables 2 to 3 to obtain a paint composition.

[0124] · Preparation of Test Plates The paint composition was applied to the surface of a pre-cleaned soda glass plate by air spraying so that the coating amount was 200 g / m 2 (dry film thickness: 50 μm). After application, the glass plate was dried at 23°C for 7 days to prepare a glass test plate.

[0125] · Preparation of Test Plates The paint composition was applied to the surface of a mortar plate with a brush so that the coating amount was 200 g / m 2 (dry film thickness: 50 μm). After application, the mortar plate was dried at 23°C for 7 days to prepare a mortar test plate.

[0126] · Antibacterial Property Evaluation Using the prepared glass test plates, an antibacterial test was carried out using Staphylococcus aureus in accordance with JIS R1752. Using a white fluorescent lamp as a light source, visible light of 380 nm or more was irradiated at an illuminance of 500 lux for 8 hours through an ultraviolet cut filter. The control was a soda glass plate that had not been antibacterial processed, that is, on which the paint composition had not been applied. TB: Number of viable bacteria per test plate after light irradiation (cfu), UB: Number of viable bacteria per control after light irradiation (cfu), and the antibacterial activity value R was determined from R = Log 10 (UB / TB). Then, the antibacterial properties of each coating film were evaluated according to the following evaluation criteria. The larger the score, the better the antibacterial property. A score of 3 to 5 is considered passing. The evaluation results are shown in conjunction with Tables 2 to 3. (Evaluation Criteria) Score 5: R is 4 or more Score 4: R is 3 or more and less than 4 Score 3: R is 2 or more and less than 3 Score 2: R is 1 or more and less than 2 Score 1: R is less than 1

[0127] · Antiviral Property Evaluation Using the prepared glass test plates, an antiviral test was carried out using bacteriophage Qβ in accordance with JIS R 1756 (2013). Using a white fluorescent lamp as a light source, visible light of 380 nm or more was irradiated at an illuminance of 500 lux for 4 hours through an ultraviolet cut filter. TV: Bacteriophage infection titer per test plate after light irradiation (pfu), UV: Bacteriophage infection titer per control after light irradiation (pfu), and the antiviral activity value V in the light were determined from V = Log 10 (UV / TV). Then, the antiviral properties of each coating film were evaluated according to the following evaluation criteria. The larger the score, the better the antiviral property. A score of 3 to 5 is considered passing. The evaluation results are shown in conjunction with Tables 2 to 3. (Evaluation Criteria) Score 5: V is 4 or more Score 4: V is 3 or more and less than 4 Score 3: V is 2 or more and less than 3 Score 2: V is 1 or more and less than 2 Score 1: V is less than 1

[0128] ·Evaluation of lightfast discoloration resistance Using the prepared mortar test panel, an accelerated weathering test was carried out in an accelerated weathering tester according to the xenon lamp method described in JIS K 5600-7-7. The test time was set to 250 hours, and the appearance of the coating film after the test time elapsed was quantified using a color difference meter in the L*a*b* color system. The L*, a*, and b* values were measured, and the difference in lightness (ΔE) from the test panel before the test was evaluated according to the following evaluation criteria. The larger the score, the smaller the discoloration due to light degradation of the coating film, indicating excellent lightfast discoloration resistance. A score of 2 or more is considered a pass. The evaluation results are shown in Tables 2 to 3. (Evaluation criteria) Score 5: ΔE is less than 2 Score 4: ΔE is 2 or more and less than 4 Score 3: ΔE is 4 or more and less than 6 Score 2: ΔE is 6 or more and less than 8 Score 1: ΔE is 8 or more

[0129] ·Evaluation of crack resistance Apply the substrate conditioner to the gypsum board with a spatula to a thickness of 2 mm and dry it at room temperature for 1 day. Then, apply the paint composition with a roller so that the coating amount is 140 g / m 2 and dry it while blowing air at room temperature. Visually evaluate the cracking condition of the coating film after it is completely dry. No crack is rated 5 points, and crack present is rated 1 point. Even a slight crack is judged as crack present and rated 1 point. The evaluation results are shown in Tables 2 to 3.

[0130]

Table 2

[0131]

Table 3

Industrial applicability

[0132] According to the present invention, it is possible to provide a coating composition capable of forming a coating film having antiviral and antibacterial properties, light degradation discoloration resistance, and crack resistance. According to the present invention, it is possible to provide a coating film having antiviral and antibacterial properties, light degradation discoloration resistance, and crack resistance. According to the present invention, it is possible to provide an article having a coating film having antiviral and antibacterial properties, light degradation discoloration resistance, and crack resistance.

Claims

1. An acrylic resin emulsion, a photocatalytic titanium oxide, and a pigment, wherein the coating composition contains: the proportion of the aromatic vinyl monomer unit in the acrylic resin of the acrylic resin emulsion is 10.0 to 52.0% by mass; the photocatalytic titanium oxide contains a metal-supported anatase-type titanium oxide; the content of the metal-supported anatase-type titanium oxide is 0.05 to 2.90 parts by mass based on 100 parts by mass of the total solid content of the coating composition; and the pigment volume concentration (PVC) of the pigment is 35 to 65%. A coating composition.

2. The coating composition according to claim 1, wherein the proportion of the aromatic vinyl monomer unit is 0.5 to 16% by mass of the total solid content of the coating composition.

3. The coating composition according to claim 1 or 2, wherein the photocatalytic titanium oxide further contains a metal-supported rutile-type titanium oxide.

4. A coating film using the coating composition according to any one of claims 1 to 3.

5. An article having the coating film according to claim 4.

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