Coating material

Abstract

To provide a coating material excellent in adhesion to various substrates and top coating materials.SOLUTION: The coating material contains a nonaqueous dispersion resin (A), an aliphatic hydrocarbon-containing nonaqueous solvent (B), a metal chelate compound (C), and a polyisocyanate compound (D) as constituent components, and the nonaqueous dispersion resin (A) has a hydroxyl group.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a novel coating material. [Background technology]

[0002] Conventionally, inorganic substrates such as concrete, mortar, slate boards, calcium silicate boards, and siding boards have been widely used as substrates for buildings, civil engineering structures, and the like. When coating these surfaces, primers are usually applied to ensure adhesion and to prevent the coating from swelling, peeling, lifting, etc. over time. Primers are also required when repairing old coating surfaces, particularly when repairing coatings with high weather resistance, stain resistance, and other functionalities applied to exterior building materials. For this reason, there is a demand for primers that have good adhesion to various substrates and coatings.

[0003] Such primers are mainly classified into solvent-based primers and water-based primers, but solvent-based primers are often used in terms of adhesion. In particular, in recent years, weak solvent primers, such as those described in Patent Document 1, which use aliphatic hydrocarbon solvents as the main solvent, have been widely used in consideration of safety during painting, work hygiene, and environmental issues. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-066744 Summary of the Invention [Problem to be solved by the invention]

[0005] On the other hand, as mentioned above, due to considerations of environmental issues, weak solvent base coats and water-based top coats are often used as top coats. However, depending on the application conditions of the weak solvent base coat and top coat, it can be difficult to ensure sufficient adhesion, and there is room for improvement.

[0006] The present invention has been made in view of the above points, and has as its object to provide a coating material that has excellent adhesion and can be suitably used as a weak solvent primer material. [Means for solving the problem]

[0007] In order to solve these problems, the present inventors have conducted extensive research and have come up with the idea of ​​a coating material containing a non-aqueous dispersion type resin and a specific compound as essential components, thereby completing the present invention.

[0008] That is, the present invention has the following features. 1. The components are a non-aqueous dispersion resin (A), an aliphatic hydrocarbon-containing non-aqueous solvent (B), and a metal chelate compound (C). Chelating aid (C') and a polyisocyanate compound (D), The non-aqueous dispersion type resin (A) has a hydroxyl group, A coating material having a hydroxyl value of 1 to 150 mgKOH / g. 2. The coating material according to 1., which contains a color pigment (E) and / or an extender pigment (F) as constituents, and the volume concentration of the pigment in the formed coating is 30 to 80%. 3. The coating material according to 1., characterized in that the coating material is a one-component type. 4. 1. The coating material according to 1, wherein the polyisocyanate compound (D) has an isocyanate group content of 10% by weight or more in the solid content. 5. 2. The coating material according to 1, wherein the molar ratio [NCO] / [OH] of the isocyanate groups of the polyisocyanate compound (D) to the hydroxyl groups of the non-aqueous dispersion type resin (A) is 0.01 to 0.5. [Effects of the Invention]

[0009] The coating material of the present invention can exhibit excellent performance in terms of adhesion and the like. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described.

[0011] The coating material of the present invention contains, as constituent components, a non-aqueous dispersion type resin (A), an aliphatic hydrocarbon-containing non-aqueous solvent (B), a metal chelate compound (C), and a polyisocyanate compound (D).

[0012] The non-aqueous dispersion resin (A) (hereinafter also referred to as "component (A)") has both a resin portion that is soluble in the aliphatic hydrocarbon-containing non-aqueous solvent (B) and a resin portion that is not soluble in the non-aqueous solvent (B), and is dispersed in the non-aqueous solvent (B) in the form of resin particles. Component (A) can be obtained, for example, by polymerizing various vinyl monomers in the presence of a resin that is soluble in the non-aqueous solvent (B) using a conventional method.

[0013] Examples of vinyl monomers used include alkyl acrylates, hydroxyl group-containing monomers, and other monomers. (Meth)acrylic acid alkyl esters are compounds having a (meth)acryloyl group and an alkyl group. In the present invention, alkyl acrylates and alkyl methacrylates are collectively referred to as alkyl (meth)acrylic acid esters. Monomers are a general term for compounds having a polymerizable unsaturated double bond.

[0014] Examples of the (meth)acrylic acid alkyl ester include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, n-pentyl (meth)acrylate, isopentyl (meth)acrylate, neopentyl (meth)acrylate, t-pentyl (meth)acrylate, 1-ethylpropyl (meth)acrylate, 2-methylbutyl (meth)acrylate, and (meth)acrylate. Examples of such acrylates include 3-methylbutyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylbutyl (meth)acrylate, 2-methylpentyl (meth)acrylate, 4-methylpentyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, n-undecyl (meth)acrylate, and n-lauryl (meth)acrylate. These can be used alone or in combination of two or more.

[0015] Examples of the hydroxyl group-containing monomer include (meth)acrylic acid hydroxyalkyl esters such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate, which can be used alone or in combination of two or more.

[0016] Examples of the other monomers include aromatic monomers, carboxyl group-containing monomers, amino group-containing monomers, pyridine-based monomers, nitrile group-containing monomers, amide group-containing monomers, epoxy group-containing monomers, carbonyl group-containing monomers, alkoxysilyl group-containing monomers, fluorine-containing monomers, ultraviolet absorbing group-containing monomers, photostable group-containing monomers, etc. These can be used alone or in combination of two or more.

[0017] The hydroxyl value (solid content) of component (A) is preferably 1 to 150 mgKOH / g (more preferably 5 to 100 mgKOH / g, and even more preferably 10 to 80 mgKOH / g). By using component (A) having such a hydroxyl value, curability (initial drying properties) can be improved, and adhesion can be enhanced. In the present invention, "a to b" is synonymous with "a or more and b or less."

[0018] Furthermore, it is preferable that component (A) has an acid value. This enhances the effects of the present invention. The acid value (solid content) of component (A) is preferably 0.1 to 30 mg KOH / g (more preferably 0.3 to 20 mg KOH / g). If it is within this range, the above effects can be further enhanced.

[0019] To set the acid value of component (A) within the above range, for example, a carboxyl group-containing vinyl monomer may be used as the other monomer. Examples of carboxyl group-containing vinyl monomers include acrylic acid, methacrylic acid, crotonic acid, maleic acid or its monoalkyl ester, itaconic acid or its monoalkyl ester, fumaric acid or its monoalkyl ester, ω-carboxy-polybutyrolactone mono(meth)acrylate, ω-carboxy-polyvalerolactone mono(meth)acrylate, ω-carboxy-polycaprolactone mono(meth)acrylate, ω-carboxy-polycaprylolactone mono(meth)acrylate, ω-carboxy-polylaurylolactone mono(meth)acrylate, (meth)acrylic acid dimer, (meth)acrylic acid trimer, (meth)acrylic acid tetramer, (meth)acrylic acid heptamer, and (meth)acrylic acid hexamer. These may be used alone or in combination of two or more.

[0020] The weight average molecular weight of component (A) is preferably 10,000 to 500,000 (more preferably 20,000 to 300,000). The glass transition temperature of component (A) is preferably -5°C to 70°C, more preferably 10°C to 60°C. The glass transition temperature is a value calculated by Fox's formula based on the vinyl monomers that make up the resin.

[0021] The aliphatic hydrocarbon-containing nonaqueous solvent (B) (hereinafter also referred to as "component (B)") is a nonaqueous solvent that is less toxic than toluene, xylene, etc., is highly safe in operation, and has little impact on air pollution. Examples of aliphatic hydrocarbons include n-hexane, n-pentane, n-octane, n-nonane, n-decane, n-undecane, and n-dodecane. These can be used alone or in combination of two or more. In the present invention, aliphatic hydrocarbons can also be introduced by using a mixed solvent such as mineral spirits. The aliphatic hydrocarbons are preferably contained in an amount of 5% by weight or more (more preferably 10 to 80% by weight) of the total amount of component (B).

[0022] Component (B) may contain a solvent that is miscible with aliphatic hydrocarbons. Examples of such solvents include petroleum-based solvents such as petroleum ether, petroleum naphtha, and solvent naphtha, as well as ethyl acetate, butyl acetate, methyl ethyl ketone, and methyl isobutyl ketone. Suitable solvents include, for example, petroleum-based solvents with a mixed aniline point or aniline point of 12 to 70°C (aromatic hydrocarbon-containing petroleum mixed solvents). The mixed aniline point or aniline point is a value measured by the method of JIS K2256:2013.

[0023] The mixing ratio of component (B) is preferably 100 to 500 parts by weight, more preferably 120 to 400 parts by weight, per 100 parts by weight of the solid content of component (A). Component (B) also includes the solvent used as a medium for each component.

[0024] Examples of the metal in the metal chelate compound (C) (hereinafter also referred to as "component (C)") include various metals such as Al, Ti, Zr, Ca, Sn, Sr, Ba, Y, V, Nb, Ta, Cr, Mo, W, Fe, Co, Ni, Cu, Bi, and lanthanoid metals. As a method for preparing the metal chelate compound, various known and commonly used methods can be used, and examples thereof include a method of reacting alkoxides of the various metals described above with a chelating agent.

[0025] Examples of the chelating agent include β-diketone compounds such as acetylacetone, dipyrroylmethane, trifluoroacetylacetone, hexafluoroacetylacetone, benzoylacetone, and dibenzoylmethane; β-ketoester compounds such as methyl acetoacetate, ethyl acetoacetate, allyl acetoacetate, benzyl acetoacetate, isopropyl acetoacetate, tert-butyl acetoacetate, isobutyl acetoacetate, 2-methoxyethyl acetoacetate, and methyl 3-keto-n-valerate; and alkanolamines such as monoethanolamine, diethanolamine, and triethanolamine.

[0026] In the present invention, the component (C) is preferably at least one selected from aluminum chelate compounds, titanium chelate compounds, and zirconium chelate compounds, with aluminum chelate compounds being particularly preferred.

[0027] Examples of aluminum chelate compounds include tris(ethylacetoacetate)aluminum, tris(n-propylacetoacetate)aluminum, tris(isopropylacetoacetate)aluminum, tris(n-butylacetoacetate)aluminum, isopropoxybis(ethylacetoacetate)aluminum, diisopropoxyethylacetoacetate aluminum, tris(acetylacetonato)aluminum, tris(propionylacetonato)aluminum, diisopropoxypropionylacetonatoaluminum, acetylacetonatobis(propionylacetonato)aluminum, monoethylacetoacetatebis(acetylacetonato)aluminum, and tris(acetylacetonato)aluminum.

[0028] Examples of titanium chelate compounds include diisopropoxy bis(ethylacetoacetate) titanate, diisopropoxy bis(acetylacetonato) titanate, and diisopropoxy bis(acetylacetonato) titanate. Examples of zirconium chelate compounds include tetrakis(acetylacetonato)zirconium, tetrakis(n-propylacetoacetate)zirconium, tetrakis(acetylacetonato)zirconium, and tetrakis(ethylacetoacetate)zirconium.

[0029] The above aluminum chelate compounds, zirconium chelate compounds, titanium chelate compounds can be used in combination of one or more types as appropriate. The amount of (C) component is preferably 0.5 to 10 parts by weight (more preferably 1.0 to 8 parts by weight, more preferably 1.5 to 8 parts by weight) relative to 100 parts by weight of the solid content of the (A) component. By being in such a range, sufficient adhesion to the substrate and topcoat material can be obtained. In particular, it is effective in improving adhesion with the topcoat material, and even if the topcoat material is an aqueous coating material, it can exhibit excellent effects in adhesion.

[0030] It is preferable to further add the chelating aid (C') (hereinafter also referred to as "component (C')"). As component (C'), the above-mentioned chelating agents can be used, and in particular, compounds such as acetoacetic esters and β-diketones are preferred. This makes it possible to obtain sufficient storage stability and further improve adhesion. It is preferable to add component (C') to component (C) in a weight ratio of 1:1 to 5. Within this range, the above-mentioned effects can be fully obtained.

[0031] The polyisocyanate compound (D) (hereinafter also referred to as "component (D)") has two or more isocyanate groups in one molecule and reacts with the component (A). Component (D) is preferably one that can react with component (A) at room temperature. Here, room temperature preferably refers to a temperature between -10°C and 50°C, more preferably between 5°C and 40°C.

[0032] Examples of component (D) include derivatives of at least one diisocyanate selected from aliphatic diisocyanates and alicyclic diisocyanates, an alcohol component, and, if necessary, a polyol component, etc., which have been subjected to alphanation, biuretization, dimerization (uretidione formation), trimerization (isocyanuration), adductization, carbodiimidization reaction, etc., and mixtures thereof. These can be used alone or in combination of two or more.

[0033] Aliphatic diisocyanates are compounds having saturated aliphatic groups in the molecule, such as 1,4-diisocyanatobutane, 1,5-diisocyanatopentane, 1,6-diisocyanatohexane (also known as hexamethylene diisocyanate (HDI)), 1,6-diisocyanato-2,2,4-trimethylhexane, and methyl 2,6-diisocyanatohexanoate (lysine diisocyanate). Alicyclic diisocyanates are compounds having cyclic aliphatic groups in the molecule, such as 5-isocyanato-1-isocyanatomethyl-1,3,3-trimethylcyclohexane (isophorone diisocyanate), 1,3-bis(isocyanatomethyl)cyclohexane (hydrogenated xylylene diisocyanate), bis(4-isocyanatocyclohexyl)methane (hydrogenated diphenylmethane diisocyanate), and 1,4-diisocyanatocyclohexane. Among these, HDI is the most preferable due to its excellent weather resistance and flexibility.

[0034] Examples of alcohol components include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, 1-pentanol, 2-pentanol, isoamyl alcohol, 1-hexanol, 2-hexanol, 1-heptanol, 1-octanol, 2-ethyl-1-hexanol, 3,3,5-trimethyl-1-hexanol, tridecanol, pentadecanol, palmityl alcohol, stearyl alcohol, cyclopentanol, cyclohexanol, methylcyclohexanol, trimethylcyclohexanol, etc. These can be used alone or in combination of two or more.

[0035] Examples of polyol components include polyether polyols, polyester polyols, and polyolefin polyols. In the present invention, polyether polyols such as polypropylene triol, polypropylene glycol, and polytetramethylene glycol are particularly suitable. These can be used alone or in combination of two or more.

[0036] The amount of component (D) blended is preferably 0.1 to 10 parts by weight (more preferably 0.2 to 5 parts by weight) per 100 parts by weight of the solid content of component (A). Sufficient adhesion can be obtained. In particular, excellent effects can be achieved in adhesion to the substrate. Furthermore, the molar ratio [NCO] / [OH] of the isocyanate groups of component (D) to the hydroxyl groups of component (A) is preferably 0.01 to 0.5 (more preferably 0.05 to 0.3). By keeping it in this range, excellent storage stability and sufficient adhesion can be obtained.

[0037] Furthermore, it is preferable that the component (D) contains a polyisocyanate compound having an isocyanate group content of 10% by weight or more (more preferably 15% by weight or more and 30% by weight or less) in the solid content. This not only ensures sufficient adhesion, but also enhances water resistance, which is effective in suppressing swelling of the coating. In the present invention, the isocyanate group content is defined as the content (% by weight) of isocyanate groups contained in the solid content of the polyisocyanate compound, and is a value determined by back titration with hydrochloric acid after neutralizing the isocyanate groups with an excess of amine.

[0038] The coating material of the present invention preferably contains a color pigment (E) and / or an extender pigment (F) in addition to the above components.

[0039] As the color pigment (E) (hereinafter also referred to as "component (E)"), chromatic pigments, white pigments, black pigments, etc. can be used. Of these, chromatic pigments are pigments that exhibit chromatic colors such as yellow, orange, red, green, blue, and purple. Examples of such chromatic pigments include inorganic pigments such as ferric oxide, ferric oxide hydroxide, ultramarine, cobalt blue, and cobalt green, and organic pigments such as azo-based, naphthol-based, pyrazolone-based, anthraquinone-based, perylene-based, quinacridone-based, disazo-based, isoindolinone-based, benzimidazole-based, phthalocyanine-based, and quinophthalone-based. On the other hand, white pigments are pigments that exhibit a white color, and examples thereof include titanium oxide, zinc oxide, and aluminum oxide. The black pigment is a pigment that exhibits a black color, and examples thereof include inorganic pigments such as iron black, iron-manganese composite oxide, iron-copper-manganese composite oxide, iron-chromium-cobalt composite oxide, copper-chromium composite oxide, and copper-manganese-chromium composite oxide, as well as carbon black. These can be used alone or in combination of two or more. Furthermore, the surface of the pigment may be treated in some way. The average particle size of component (E) is preferably 1 μm or less, more preferably 0.01 to 0.9 μm.

[0040] The blending amount of component (E) is preferably 5 to 100 parts by weight (more preferably 10 to 80 parts by weight) per 100 parts by weight of the solid content of component (A). With component (E) in this ratio, the coating material can be colored to a desired color, and hiding power, aesthetics, etc. can be improved.

[0041] The extender pigment (F) (hereinafter also referred to as "component (F)") can be used for purposes such as adjusting the solid content, adjusting the viscosity, adjusting the gloss (such as reducing gloss), or improving storage stability and pigment compatibility. Examples of component (F) include heavy calcium carbonate, light calcium carbonate, kaolin, clay, china clay, diatomaceous earth, hydrous finely powdered silicic acid, talc, barite powder, barium sulfate, precipitated barium sulfate, barium carbonate, magnesium carbonate, silica powder, and aluminum hydroxide. These can be used alone or in combination of two or more. The average particle size of component (F) is preferably 0.1 to 100 μm (preferably 1 to 80 μm).

[0042] The amount of component (F) added is preferably 10 to 500 parts by weight (more preferably 20 to 300 parts by weight) per 100 parts by weight of the solid content of component (A).

[0043] In the present invention, the component (E) and / or the component (F) are blended so that the pigment volume concentration in the formed coating film is preferably 30 to 80% (more preferably 35 to 65%). With such a pigment volume concentration, a coating film with sufficient adhesion can be formed.

[0044] In addition to the components described above, the coating material of the present invention may contain various other components to the extent that they do not affect the effects of the present invention. Examples of such components include plasticizers, preservatives, antifungal agents, anti-algae agents, antifoaming agents, leveling agents, pigment dispersants, thickeners, antiskinning agents, dehydrating agents, matting agents, UV absorbers, light stabilizers, antioxidants, and catalysts. The coating material of the present invention may also contain resin components other than the component (A). The coating material of the present invention can be produced by uniformly stirring and mixing the above components (A) to (D) (preferably components (A) to (F)) as constituent components, and, if necessary, other components, by conventional methods. Furthermore, the coating material of the present invention is preferably used in a one-component form.

[0045] The coating material of the present invention can be preferably applied to substrates or old paint films as a primer. Examples of substrates include concrete, mortar, slate board, calcium silicate board, ALC board, extrusion molded board, slate roofing tiles, cement roofing tiles, new roofing tiles, porcelain tiles, siding boards, metal, glass, wood, and plywood.

[0046] The old paint film is a paint film that has been applied on the above-mentioned substrate, and examples thereof include weather-resistant topcoat paint for architecture (JISK5658:2010), weather-resistant paint for steel structures (JISK5659:2008), glossy synthetic resin emulsion paint (JISK5660:2008), fire-resistant paint for architecture (JISK5661:1970), synthetic resin emulsion paint (JISK5663:2008), road marking paint (JISK5665:2011), and multicolored pattern paint (JISK5667 :2003), synthetic resin emulsion pattern paint (JISK5668:2010), acrylic resin non-aqueous dispersion paint (JISK5670:2008), lead- and chromium-free anti-rust paint (JISK5674:2008), high solar reflectance paint for roofs (JISK5675:2011), building floor paint (JISK5970:2008), architectural waterproof coating material (JISA6021:2011), architectural finish coating material (JISA6909:2014), etc. In particular, the present invention can also be applied to fluororesin coating film, silicone resin coating film, etc.

[0047] The coating material of the present invention can be applied by various methods, such as brush coating, roller coating, spray coating, etc. When coating in a factory, a roll coater, flow coater, etc. can also be used.

[0048] The coating amount is preferably 0.1 to 0.6 kg / m 2 (More preferably 0.2 to 0.5 kg / m 2 The number of applications may be determined as appropriate depending on the surface condition of the substrate, but is preferably 1 to 2 times. The drying time is preferably 1 hour to 1 week. The drying temperature is preferably -10°C to 50°C (more preferably -5°C to 40°C).

[0049] In the present invention, after the coating material is applied and dried, a topcoat material can be applied. By applying a topcoat material, it is possible to protect the finished surface or improve its aesthetic appearance.

[0050] Various resins can be used as the resin component in the topcoat material. Examples of resin types include vinyl acetate resin, polyester resin, alkyd resin, vinyl chloride resin, epoxy resin, acrylic resin, urethane resin, acrylic silicone resin, fluororesin, etc., or composite resins thereof. Among these, one or more types selected from acrylic resin, urethane resin, acrylic silicone resin, fluororesin, etc. are suitable. In addition, examples of the form of such resin components include water-soluble resin, water-dispersible resin (resin emulsion), solvent-soluble resin, solventless resin, non-water-dispersible resin, powdered resin, etc., among which, one or more types selected from water-based topcoat materials such as water-soluble resin, water-dispersible resin, solvent-soluble resin, non-water-dispersible resin, etc. are suitable. When the coating material of the present invention is used as a primer, sufficient adhesion can be ensured even with a water-based topcoat material.

[0051] Such topcoat materials may contain various components other than the above-mentioned components, as long as the effects of the present invention are not significantly impaired. Such components include, for example, thickeners, film-forming aids, leveling agents, wetting agents, plasticizers, antifreeze agents, pH adjusters, coloring pigments, extender pigments, aggregates, preservatives, antifungal agents, anti-algae agents, antibacterial agents, dispersants, antifoaming agents, adsorbents, fibers, crosslinking agents, UV absorbers, light stabilizers, antioxidants, anti-pollution agents, hydrophilizing agents, water repellents, catalysts, solvents, and water. The topcoat material of the present invention can be manufactured by uniformly mixing the above-mentioned resin components and, if necessary, the various components described above using conventional methods. The form of the topcoat material can be, for example, a one-component type, a two-component type, or a multi-component type.

[0052] In painting the topcoat material, known painting tools can be used. Examples of painting tools that can be used include sprays, rollers, brushes, etc. The amount of topcoat material to be applied may be set appropriately depending on the surface shape of the existing wall, the type of topcoat material, the type of painting equipment, etc., but is preferably 0.1 to 0.5 kg / m 2 (More preferably 0.2 to 0.4 kg / m 2When painting, the top coat can be diluted as needed. [Example]

[0053] The following examples will clarify the features of the present invention. <Manufacturing of coating materials> According to the formulation shown in Table 1, the components were mixed and stirred in a standard manner to obtain a coating material.

[0054] The following raw materials were used: (A) Non-aqueous dispersion resin (A1): Non-aqueous dispersion type acrylic polyol (acrylic acid alkyl ester-methacrylic acid acrylic ester-methacrylic acid hydroxyalkyl ester copolymer dispersion [hydroxyl value 40 mg KOH / g, acid value 2 mg KOH / g, weight average molecular weight 70,000, solid content 50 wt%, medium: mineral spirits (aniline point 42°C)] (A2): Non-aqueous dispersion type acrylic polyol (acrylic acid alkyl ester-methacrylic acid acrylic ester-methacrylic acid alkyl ester copolymer dispersion [hydroxyl value 0 mg KOH / g, acid value 2 mg KOH / g, weight average molecular weight 70,000, solid content 50 wt%, medium: mineral spirits (aniline point 42°C)] (B) Aliphatic hydrocarbon-containing nonaqueous solvent Mineral spirits (C) Metal chelate compounds Aluminum chelate compound [ethyl acetoacetate aluminum diisopropylate (Al content: 9.8% by weight)] (C') Chelating aid Acetylacetone (D) Polyisocyanate compound (D1): Hexamethylene diisocyanate derivative solution [solid content: 100% by weight, isocyanate group content: 21% by weight] (D2): Hexamethylene diisocyanate derivative solution [solid content: 100% by weight, isocyanate group content: 12% by weight] (E) Coloring pigments Rutile titanium dioxide (average particle size: 0.3 μm, specific gravity: 4.2) (F) Extender pigment Calcium carbonate (average particle size: 10-20 μm, specific gravity 2.7) (additives) Antifoaming agents, thickeners, dispersants, etc.

[0055] (Examples 1 to 10, Comparative Examples 1 to 4) The resulting coating materials were used to carry out the following evaluations. <Adhesion evaluation 1> □ Apply 0.30 kg / m of coating material to a siding board that has an inorganic clear coating as an existing coating. 2 The coating was applied so that the coating was as shown in the figure, and the specimen [I] was prepared by drying it for 24 hours under standard conditions (temperature 23°C, relative humidity 50%). The prepared test specimen [I] was evaluated for adhesion using the cross-cut tape method in accordance with JIS K 5600-5-6. The evaluation criteria are as follows: AA: Defect area less than 5% A: Defect area is 5% or more but less than 10% AB: Defect area is 10% or more but less than 25% B: Defect area is 25% or more but less than 40% C: Defect area is 40% or more but less than 55% D: Defective area is 55% or more

[0056] <Adhesion evaluation 2> □ Apply 0.30 kg / m of coating material to a siding board that has an inorganic clear coating as an existing coating. 2 The surface is then dried for 24 hours under standard conditions (temperature 23°C, relative humidity 50%), and then a water-based topcoat (acrylic silicone resin emulsion paint) is applied at a rate of 0.20 kg / m. 2 The test specimen [II] was prepared by applying the paint as shown in the figure and drying it for 24 hours in a 50°C environment. The prepared specimen [II] was evaluated in the same manner as in Adhesion Evaluation 1.

[0057] <Adhesion evaluation 3> The prepared specimen [II] was immersed in water at 20°C for 3 days, then removed and dried (23°C, 3 hours), and the condition of the coating was visually observed and evaluated for swelling, peeling, whitening, etc. The evaluation criteria were a four-point scale (A>B>C>D), with "A" being almost no abnormality and "D" being abnormality.

[0058] Good adhesion was obtained in Examples 1 to 10. In particular, in Examples 3 to 7, excellent adhesion was obtained to both the substrate and the water-based topcoat material.

[0059] Furthermore, Examples 1 to 10 were evaluated as follows. <Storage stability> After the preparation of the dressing material, it was left at 20°C for 14 days, and the change in appearance was visually observed. The evaluation criteria were a four-point scale (A>B>C>D), with "A" being almost no abnormality and "D" being abnormality.

[0060] No particular abnormalities were observed and good storage stability was ensured in Examples 2 to 4 and 7 to 10. On the other hand, slight abnormalities (viscosity increase) were observed in Examples 1, 5 and 6.

[0061] [Table 1]

Claims

1. The composition includes, as constituent components, a non-aqueous dispersion type resin (A), an aliphatic hydrocarbon-containing non-aqueous solvent (B), a metal chelate compound (C), a chelating aid (C'), and a polyisocyanate compound (D), The coating material is characterized in that the non-aqueous dispersion type resin (A) has a hydroxyl group and a hydroxyl value of 1 to 150 mgKOH / g.

2. 2. The coating material according to claim 1, characterized in that it contains a color pigment (E) and / or an extender pigment (F) as constituent components, and the volume concentration of the pigment in the formed coating is 30 to 80%.

3. The coating material described in claim 1, characterized in that the coating material is a one-component type.

4. The coating material described in claim 1, characterized in that the polyisocyanate compound (D) has an isocyanate group content in the solid content of 10% by weight or more.

5. The coating material described in claim 1, characterized in that the molar ratio [NCO] / [OH] of the isocyanate groups of the polyisocyanate compound (D) to the hydroxyl groups of the non-aqueous dispersion type resin (A) is 0.01 to 0.5.