Covering material

Abstract

To provide a coating material capable of forming a coating film which has sufficient stain resistance and is excellent in substrate followability and the like.SOLUTION: The present invention is the coating material comprising a main agent and a curing agent. The main agent contains a hydroxyl group-containing resin (A). The curing agent contains a polyisocyanate compound (B) and a silicate compound (C). As the hydroxyl group-containing resin (A), a nonaqueous dispersion type resin (a1) having a hydroxyl value of 30 mg KOH / g or more and a soluble resin (a2) having a hydroxyl value of 30 mg KOH / g or more are contained. The hydroxyl value of the nonaqueous dispersion type resin (a1) is higher than the hydroxyl value of the soluble resin (a2).SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] Traditionally, paint finishes have been applied to buildings, civil engineering structures, and other structures to protect their frames, add design features, and improve their aesthetic appearance, and durable coating materials such as fluororesin, acrylic silicone resin, and polyurethane resin have been widely used. However, due to their durability, these durable coating materials can sometimes cause problems with contamination of the coating surface. In particular, in places where automobile exhaust gases and the like are present in large amounts in the air, oily contaminants can adhere to the coating surface, causing streak-like contamination (hereinafter referred to as "rain streaks"), which can render the paint finish applied to improve the urban landscape meaningless.

[0003] In response to this, various coating materials have been published that make the coating surface hydrophilic so that the oily contaminants adhering to the coating surface can be peeled off and washed away by the action of rainwater spreading over the coating surface during rainfall. For example, Patent Document 1 proposes blending a silicate compound and a hydrophilicity-imparting agent into a polyurethane resin. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 10-140083 Summary of the Invention [Problem to be solved by the invention]

[0005] However, although the addition of silicate compounds improves stain resistance, if the weather resistance of the coating film is insufficient, the stain resistance may not be maintained for a long period of time. Furthermore, coatings containing silicate compounds may not be able to achieve sufficient conformability depending on the type of substrate.

[0006] The present invention has been made in view of the above points, and has as its object to provide a coating film that has sufficient stain resistance, as well as excellent weather resistance and conformability. [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 specific resin component as an essential component, thereby completing the present invention.

[0008] That is, the present invention has the following features. 1. A coating material having a base agent and a curing agent, The base resin contains a hydroxyl group-containing resin (A), The curing agent contains a polyisocyanate compound (B) and a silicate compound (C), The hydroxyl group-containing resin (A) includes a non-aqueous dispersion type resin (a1) having a hydroxyl group value of 30 mgKOH / g or more and a soluble type resin (a2) having a hydroxyl group value of 30 mgKOH / g or more, A coating material characterized in that the hydroxyl value of the non-aqueous dispersion type resin (a1) is greater than the hydroxyl value of the soluble type resin (a2). 2. The coating material according to 1., wherein the hydroxyl-containing resin (A) contains a silicone component. 3. The coating material according to 1. or 2., wherein the non-aqueous dispersion type resin (a1) contains a silicone component. 4. The coating material according to any one of 1. to 3., wherein the polyisocyanate compound (B) comprises a polyisocyanate compound (b1) having an isocyanate group content of less than 14% by weight and a polyisocyanate compound (b2) having an isocyanate group content of 14% by weight or more. [Effects of the Invention]

[0009] The coating material of the present invention can form a coating film that has sufficient stain resistance, as well as excellent weather resistance and conformability to the substrate. DETAILED DESCRIPTION OF THE INVENTION

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

[0011] The coating material of the present invention has a base agent and a curing agent, and the base agent contains a hydroxyl group-containing resin (A), and the curing agent contains a polyisocyanate compound (B) and a silicate compound (C).

[0012] (Main ingredient) The base resin contains a hydroxyl-containing resin (A) (hereinafter also referred to as "component (A)"), which includes a non-aqueous dispersible resin (a1) having a hydroxyl value of 30 mgKOH / g or more and a soluble resin (a2) having a hydroxyl value of 30 mgKOH / g or more, and the hydroxyl value of the non-aqueous dispersible resin (a1) is greater than that of the soluble resin (a2). In this case, the crosslink density of the coating increases, resulting in excellent weather resistance, stain resistance, adhesion, and other properties. The mechanism of this action is not limited, but it is believed that the soluble resin (a2), which exhibits a slightly slower crosslinking reaction, crosslinks between particles of the non-aqueous dispersible resin (a1), resulting in a uniform distribution of hydroxyl groups in the coating and less bias in the crosslinking reaction. This is thought to result in the formation of a uniform coating with a high crosslink density, improving weather resistance, stain resistance, and conformability. On the other hand, if the hydroxyl value of component (A) [non-aqueous dispersion type resin (a1) and soluble type resin (a2)] is less than 30 mgKOH / g, the crosslink density will be low, the physical properties of the coating will be deteriorated, and it will be difficult to fully obtain the above-mentioned effects. The hydroxyl value is a value expressed as the number of mg of potassium hydroxide equivalent to the moles of hydroxyl groups contained in 1 g of sample.

[0013] Specifically, the hydroxyl value of the non-aqueous dispersion type resin (a1) is 30 mgKOH / g or more (preferably 35 to 200 mgKOH / g, more preferably 40 to 150 mgKOH / g), and the hydroxyl value of the soluble type resin (a2) is 30 mgKOH / g or more (preferably 31 to 150 mgKOH / g, more preferably 35 to 100 mgKOH / g). In such cases, the crosslinking density of the coating increases, and excellent effects can be exhibited in weather resistance, stain resistance, conformability, etc. In the present invention, "α to β" is synonymous with "α or more and β or less."

[0014] In the present invention, the hydroxyl value of the non-aqueous dispersion type resin (a1) is larger than the hydroxyl value of the soluble type resin (a2), and the difference in hydroxyl value is preferably 1 to 50 KOHmg / g (more preferably 2 to 40 KOHmg / g). In such a case, the effects of the present invention can be further enhanced.

[0015] Furthermore, the mixing weight ratio of the non-aqueous dispersion type resin (a1) to the soluble type resin (a2) [(a1) / (a2)] is preferably 99 / 1 to 50 / 50 (more preferably 98 / 2 to 60 / 40), which can further enhance the above-mentioned effects.

[0016] In the component (A) of the present invention, the non-aqueous dispersion resin (a1) is a hydroxyl-containing resin (A) dispersed as resin particles in a non-aqueous solvent, and the soluble resin (a2) is a hydroxyl-containing resin (A) dissolved in a non-aqueous solvent.

[0017] The non-aqueous solvent preferably contains an aliphatic hydrocarbon-containing non-aqueous solvent (so-called weak solvent). The aliphatic hydrocarbon-containing non-aqueous solvent is less toxic than toluene, xylene, etc., and is therefore safer to work with and has less 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 hydrocarbon is preferably contained in an amount of 5% by weight or more, more preferably 10 to 80% by weight, based on the total amount of the non-aqueous solvent.

[0018] The non-aqueous solvent 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 having a mixed aniline point or an aniline point of 12 to 70°C (aromatic hydrocarbon-containing petroleum mixed solvent). The mixed aniline point or the aniline point is a value measured by the method of JIS K2256:2013.

[0019] The component (A) of the present invention may be any resin containing a hydroxyl group, such as polyether polyol, polyester polyol, acrylic polyol, or fluorine-containing polyol. Other examples include phenol resin polyol, epoxy polyol, polybutadiene polyol, polyisoprene polyol, polyester-polyether polyol, urea-dispersed polyol, and carbonate polyol. One or more of these can be used as the component (A). It is particularly preferred that the component (A) of the present invention contains an acrylic polyol.

[0020] The acrylic polyol may be a copolymer of a hydroxyl group-containing monomer, a (meth)acrylic acid alkyl ester, and, if necessary, other monomers. Examples of hydroxyl group-containing monomers include hydroxyalkyl esters of (meth)acrylic acid such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, hydroxypropyl vinyl ether, hydroxybutyl vinyl ether, and hydroxypentyl vinyl ether; and hydroxyallyl ethers such as ethylene glycol monoallyl ether, diethylene glycol monoallyl ether, and triethylene glycol monoallyl ether. One or more of these can be used.

[0021] Examples of (meth)acrylic acid alkyl esters include methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-amyl (meth)acrylate, isoamyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, octadecyl (meth)acrylate, and cyclohexyl (meth)acrylate, and one or more of these can be used.

[0022] Other monomers include, for example, amino group-containing monomers such as dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, dimethylamino (meth)acrylate, aminoethyl (meth)acrylate, and diethylaminoethyl (meth)acrylate; carboxyl group-containing monomers such as acrylic acid, methacrylic acid, crotonic acid, maleic acid or its monoalkyl ester, itaconic acid or its monoalkyl ester, and fumaric acid or its monoalkyl ester; amide group-containing monomers such as (meth)acrylamide and ethyl (meth)acrylamide; nitrile group-containing monomers such as (meth)acrylonitrile; and glycidyl Examples include epoxy group-containing monomers such as (meth)acrylates; alkoxysilyl group-containing monomers such as vinyltrimethoxysilane, vinyltriethoxysilane, γ-(meth)acryloyloxypropyltrimethoxysilane, γ-(meth)acryloyloxypropyltriethoxysilane, and γ-(meth)acryloyloxypropylmethyldimethoxysilane, or silicone compounds having a polymerizable double bond; aromatic hydrocarbon monomers such as styrene, methylstyrene, chlorostyrene, and vinyltoluene; and vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, and vinyl pivalate, and one or more of these can be used as necessary.

[0023] Furthermore, it is preferable that component (A) contains a silicone component as a constituent. It is particularly preferable that the non-aqueous dispersion type resin (a1) contains a silicone component. By including a silicone component in the non-aqueous dispersion type resin (a1) having a large hydroxyl value, a silicone coating with an increased crosslinking density is formed, further enhancing the effect of improving long-term weather resistance. The silicone component may be linear, branched, cyclic, or other such forms. The content of the silicone component is preferably 0.1 to 20 wt % (more preferably 0.5 to 10 wt %), calculated as SiO2, based on the resin solids. Within this range, it is possible to obtain an effect of improving long-term weather resistance and ensure conformability to the substrate. It is also possible for the soluble resin (a2) to be free of a silicone component, taking into account conformability to the substrate, adhesion, flexibility, and the like.

[0024] In the present invention, the SiO2 equivalent is expressed as the weight of silica (SiO2) that remains when a compound having an Si-O bond is completely hydrolyzed and then fired at 900°C. Generally, alkoxysilanes, silicates, silicones, etc. react with water to undergo a hydrolysis reaction to become silanols, which then have the property of undergoing a condensation reaction between silanols or between silanols and alkoxy. When this reaction is carried to the extreme, silica (SiO2) is formed. These reactions are as follows: RO(Si(OR)2O)nR+(n+1)H2O→nSiO2+(2n+2)ROH (R represents an alkyl group. n is an integer.) The SiO2 equivalent in the present invention is the amount of the remaining silica component calculated based on this reaction formula.

[0025] The method for introducing silicone into component (A) is not particularly limited, and various methods can be used. (1) A method of copolymerizing a silicone compound having a polymerizable double bond; (2) A method of reacting a functional group in a resin with a silicone compound having a functional group capable of reacting with the functional group; (3) A method of reacting a resin copolymerized with a reactive silyl group-containing monomer with a reactive silyl group-containing compound; (4) A method in which a functional group in a resin is reacted with a coupling agent having a functional group capable of reacting with the functional group, and then a reactive silyl group-containing compound is reacted therewith.

[0026] Examples of the combination of functional groups in (2) and (4) above include a hydroxyl group and an isocyanate group, a hydroxyl group and a carboxylic anhydride group, an amino group and an isocyanate group, a carboxyl group and an epoxy group, an amino group and an epoxy group, and an alkoxysilyl group and an alkoxysilyl group.

[0027] The reactive silyl group in (3) and (4) above is one in which an alkoxyl group, a phenoxy group, a mercapto group, an amino group, a halogen, or the like is bonded to a silicon atom. The reactive silyl group-containing compound is one having two or more reactive silyl groups in one molecule, and examples thereof include tetrafunctional alkoxysilanes such as tetraethoxysilane, tetramethoxysilane, and tetrabutoxysilane; trifunctional alkoxysilanes such as methyltrimethoxysilane, methyltriethoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltributoxysilane, propyltrimethoxysilane, propyltriethoxysilane, butyltrimethoxysilane, butyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, and phenyltributoxysilane; dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldibutoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, dipropyldimethoxysilane, and dipropyl Examples of suitable alkoxysilanes include difunctional alkoxysilanes such as diethoxysilane, dibutyldimethoxysilane, dibutyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, diphenyldibutoxysilane, methylphenyldimethoxysilane, and methylphenyldiethoxysilane; chlorosilanes such as tetrachlorosilane, methyltrichlorosilane, ethyltrichlorosilane, propyltrichlorosilane, phenyltrichlorosilane, vinyltrichlorosilane, dimethyldichlorosilane, diethyldichlorosilane, diphenyldichlorosilane, and methylphenyldichlorosilane; and acetoxysilanes such as tetraacetoxysilane, methyltriacetoxysilane, phenyltriacetoxysilane, dimethyldiacetoxysilane, and diphenyldiacetoxysilane. One or more of these compounds can be used. Compounds having one reactive silyl group per molecule can also be used in combination.

[0028] The reactive silyl group-containing monomer in (3) above is a compound containing a reactive silyl group and a polymerizable double bond, and examples thereof include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri-n-butoxysilane, vinyltris(β-methoxyethoxy)silane, allyltrimethoxysilane, trimethoxysilylethyl vinyl ether, triethoxysilylethyl vinyl ether, trimethoxysilylpropyl vinyl ether, triethoxysilylpropyl vinyl ether, γ-(meth)acryloyloxypropyltrimethoxysilane, γ-(meth)acryloyloxypropyltriethoxysilane, γ-(meth)acryloyloxypropylmethyldimethoxysilane, vinylmethyldimethoxysilane, methyldimethoxysilylethyl vinyl ether, and methyldimethoxysilylpropyl vinyl ether, and one or more of these may be used.

[0029] The coupling agent in (4) above is, for example, a compound having at least one alkoxysilyl group and other substituents in one molecule.Specific examples of the coupling agent include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, isocyanate-functional silane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, etc., and one or more of these can be used.

[0030] The glass transition temperature of component (A) is preferably -10 to 80°C (more preferably 0 to 60°C). If the glass transition temperature is within this range, the physical properties of the coating, such as stain resistance, flexibility, and durability, can be improved. The glass transition temperature is a value calculated by Fox's formula based on the vinyl monomers that make up the resin.

[0031] (hardening agent) The curing agent contains (B) a polyisocyanate compound and (C) a silicate compound.

[0032] The (B) polyisocyanate compound (hereinafter also referred to as "component (B)") has two or more isocyanate groups per molecule and reacts with the (A) component to form a coating. Component (B) is preferably one that can crosslink 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. The isocyanate group content of the solid content of component (B) is preferably between 2% and 30% by weight.

[0033] Examples of component (B) 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.

[0034] 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 preferred due to its excellent weather resistance and flexibility. (Hereinafter, aliphatic diisocyanates and alicyclic diisocyanates will be collectively referred to as "diisocyanates.")

[0035] 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.

[0036] 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.

[0037] In the present invention, it is preferable to include a polyisocyanate compound (b1) (hereinafter referred to as "component (b1)") having an isocyanate group content of less than 14 wt% (preferably 2 wt% to 13 wt%) in the solid content, and a polyisocyanate compound (b2) (hereinafter referred to as "component (b2)") having an isocyanate group content of 14 wt% or more (preferably 15 wt% to 30 wt%). The combined use of component (b1) and component (b2) can provide excellent stain resistance and conformability to the substrate. In particular, excellent conformability can be achieved even when the substrate is a sealant-containing substrate. Furthermore, excellent crack resistance (flexibility) can also be achieved. In the present invention, the isocyanate group content is defined as the content (wt%) of isocyanate groups 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] In the present invention, the component (B) preferably contains 20 to 90% by weight (more preferably 30 to 80% by weight, and even more preferably 45 to 75% by weight) of the component (b1).Within such a range, the above effects can be further enhanced.

[0039] The mixing ratio of component (B) may be set in consideration of the molar ratio [NCO] / [OH] of the isocyanate groups of component (B) to the hydroxyl groups of component (A). The molar ratio [NCO] / [OH] of the isocyanate groups of component (B) to the hydroxyl groups of component (A) is preferably 0.6 to 1.4 (more preferably 0.8 to 1.3). Such a ratio can further enhance the effects of the present invention.

[0040] The mixing ratio (weight ratio) of component (A) to component (B) is set based on the hydroxyl value of component (A) and the isocyanate group content of component (B). In the coating material of the present invention, the mixing ratio of component (B) is preferably 5 to 50 parts by weight (more preferably 10 to 40 parts by weight) per 100 parts by weight of the resin solid content of component (A).

[0041] The silicate compound (C) (hereinafter also referred to as "component (C)") mainly functions to impart hydrophilicity to the formed coating. Examples of such component (C) that can be used include tetraalkoxysilanes, tetraalkoxysilane condensates, and modified products thereof. Examples of tetraalkoxysilanes include tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetraisobutoxysilane, tetra-sec-butoxysilane, tetra-t-butoxysilane, tetraphenoxysilane, monoethoxytrimethoxysilane, monobutoxytrimethoxysilane, monopentoxytrimethoxysilane, monohexoxytrimethoxysilane, dimethoxydiethoxysilane, and dimethoxydibutoxysilane. These compounds can be used alone or in combination of two or more.

[0042] In the present invention, it is preferable to use a condensate (c1) (hereinafter referred to as "component (c1)") of a tetraalkoxysilane containing an alkoxyl group having 1 to 2 carbon atoms and an alkoxyl group having 3 to 12 carbon atoms. In particular, component (c1) is preferably one in which 5 to 50% by weight of the alkoxyl groups in the entire compound are alkoxyl groups having 3 to 12 carbon atoms.

[0043] Examples of the alkoxyl group having 3 to 12 carbon atoms include linear alkoxyl groups such as n-propoxy, n-butoxy, n-pentyloxy, n-hexyloxy, n-octyloxy, and n-dodecyloxy groups, and branched alkoxyl groups such as isopropoxy, isobutoxy, t-butoxy, sec-butoxy, isopentyloxy, neopentyloxy, isohexyloxy, 3-methylpentyloxy, 1-methylhexyloxy, 1-ethylpentyloxy, 2,3-dimethylbutoxy, 1,5-dimethylhexyloxy, 2-ethylhexyloxy, 1-methylheptyloxy, and t-octyloxy groups.

[0044] Component (c1) can be produced by known methods, such as modifying a tetraalkoxysilane condensate having an alkoxyl group having from 1 to 2 carbon atoms with an alcohol having from 3 to 12 carbon atoms.

[0045] The mixing ratio of component (C) is preferably 0.1 to 50 parts by weight (more preferably 1 to 30 parts by weight) per 100 parts by weight of the resin solid content of component (A).With component (C) in this range, excellent stain resistance and other effects can be obtained.

[0046] The mixing ratio of the above-mentioned (B) component and the above-mentioned (C) component is preferably 5 to 80 parts by weight (more preferably 10 to 60 parts by weight) of the (C) component per 100 parts by weight of the solid content of the (B) component.With the (C) component in this range, excellent stain resistance effects can be obtained.

[0047] The curing agent of the present invention can be produced by uniformly stirring and mixing the above components (B) and (C) by a conventional method.

[0048] (covering material) The coating material of the present invention preferably contains, in addition to the above-mentioned components, a powder component (D) (hereinafter also referred to as "component (D)") in the base agent and / or curing agent. Examples of component (D) include color pigments and extender pigments.

[0049] As the color pigment, chromatic pigments, white pigments, black pigments, etc. can be used. By including such color pigments, it is possible to express various colors. Among 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 pigments, naphthol pigments, pyrazolone pigments, anthraquinone pigments, perylene pigments, quinacridone pigments, disazo pigments, isoindolinone pigments, benzimidazole pigments, phthalocyanine pigments, and quinophthalone pigments. On the other hand, white pigments are pigments that exhibit a white color, such as 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.

[0050] The average particle size of the color pigment is preferably 1 μm or less, more preferably 0.01 to 0.9 μm. The average particle size of the color pigment is a value measured using a laser diffraction particle size distribution analyzer. The mixing ratio of the color pigment is preferably 1 to 200 parts by weight (more preferably 5 to 150 parts by weight) per 100 parts by weight of the solid content of component (A).

[0051] Extender pigments can be used for purposes such as adjusting the solids content, viscosity, and gloss (such as reducing gloss), or improving storage stability and pigment compatibility. Examples of extender pigments include heavy calcium carbonate, light calcium carbonate, kaolin, clay, bentonite, china clay, diatomaceous earth, hydrous finely powdered silicic acid, talc, baryte powder, barium sulfate, precipitated barium sulfate, barium carbonate, magnesium carbonate, silica powder, and aluminum hydroxide, which may be treated in some way (such as by surface treatment). These can be used alone or in combination of two or more.

[0052] The average particle size of the extender pigment is preferably 0.01 to 10 μm (more preferably 0.05 to 5 μm). The average particle size of the extender pigment is a value measured using a laser diffraction particle size distribution analyzer. The blend ratio of the extender pigment is preferably 1 to 150 parts by weight (more preferably 5 to 100 parts by weight) per 100 parts by weight of the solid content of component (A).

[0053] The blend ratio of component (D) is preferably 1 to 300 parts by weight (more preferably 5 to 250 parts by weight) per 100 parts by weight of the solid content of component (A). When component (D) contains a powder component (d1) (hereinafter also referred to as "component (d1)") having a specific gravity of 3.0 or greater, it is preferable to also contain a powder component (d2) (hereinafter also referred to as "component (d2)") having a specific gravity of less than 3.0. The blend weight ratio of component (d1) to component (d2) [(d1) / (d2)] is preferably 99.5 / 0.5 to 70 / 30 (more preferably 99 / 1 to 80 / 20). This enhances the dispersion stability of component (D) relative to component (A), resulting in excellent pigment compatibility, color stability, and gloss. It is also advantageous in improving weather resistance. The reason for this effect is not limited, but it is presumed that by using the (d2) component in combination with the (d1) component, which has a large specific gravity, the (d2) component acts as a spacer for the (d1) component, thereby increasing the dispersion stability of the (d1) component.

[0054] The coating material of the present invention may contain various other components in the base resin and / or curing agent in addition to the above-mentioned components, provided that the components do not affect the effects of the present invention. Examples of such components include catalysts, plasticizers, preservatives, antifungal agents, anti-algae agents, antifoaming agents, leveling agents, pigment dispersants, thickeners, anti-skinning agents, dehydrating agents, matting agents, UV absorbers, light stabilizers, antioxidants, and solvents. The coating material of the present invention may also contain resin components other than the above-mentioned component (A). The coating material of the present invention is a two-component coating material consisting of a base resin and a curing agent, and the base resin and curing agent are mixed together before application.

[0055] The coating material of the present invention can be applied mainly to buildings, civil engineering structures, etc. Examples of substrates that constitute such parts include concrete, mortar, siding boards, extruded boards, ALC, gypsum boards, perlite boards, tiles, glass boards, wood boards, plastic boards, metal boards, etc. These substrates may be subjected to some kind of surface treatment (filler treatment, putty treatment, surfacer treatment, sealer treatment, etc.) or may already have a coating film formed thereon.

[0056] The coating material of the present invention can be diluted during application, and the above-mentioned aliphatic hydrocarbon-containing non-aqueous solvent is preferred as the diluent.

[0057] As a coating method, various methods can be used, such as brush coating, roller coating, spray coating, etc. The amount of coating applied at the time of coating is preferably 30 to 250 g / m per coating. 2 , more preferably 50 to 200 g / m 2 In addition, after a coating is applied once and the coating film has dried, the next coating (recoating) can be applied. The drying temperature is preferably -10 to 50°C, more preferably -5 to 40°C. The number of coatings is preferably two or more. [Example]

[0058] The following examples will clarify the features of the present invention. (A) Polyol compound (A1) Acrylic polyol compound dispersion (solid content: 50% by weight, hydroxyl value (solid content): 55 KOH mg / g, medium: mineral spirits) (A2) Silicone-containing acrylic polyol compound dispersion (solid content: 50% by weight, hydroxyl value (solid content): 55 KOH mg / g, silicone component content: 3% by weight (SiO2 equivalent), medium: mineral spirits) (A3) Acrylic polyol compound dispersion (solid content: 50% by weight, hydroxyl value (solid content): 28 KOH mg / g, medium: mineral spirits) (A4) Acrylic polyol compound solution (solid content: 50% by weight, hydroxyl value (solid content): 65 KOH mg / g, medium: methyl ethyl ketone) (A5) Acrylic polyol compound solution (solid content: 50% by weight, hydroxyl value (solid content): 40 KOH mg / g, medium: mineral spirits) (A6) Acrylic polyol compound solution (solid content: 50% by weight, hydroxyl value (solid content): 28 KOH mg / g, medium: mineral spirits) The above (A1) to (A3) are non-aqueous dispersion type resins (a1), and the above (A4) to (A6) are soluble type resins (a2). (B) Polyisocyanate compound (B1) Hexamethylene diisocyanate derivative solution (solid content: 100% by weight, isocyanate group content: 12% by weight) (B2) Hexamethylene diisocyanate derivative solution (solid content: 100% by weight, isocyanate group content: 21% by weight) (B3) Hexamethylene diisocyanate derivative solution (solid content: 100% by weight, isocyanate group content: 17% by weight) The above (B1) is the (b1) component, and the above (B2) and (B3) are the (b2) component. (C) Silicate compounds (C1) Tetramethoxysilane (C2) i-butyl alcohol modified tetramethoxysilane compound (average condensation degree 4, transesterification rate 30%, residual silica rate 40%) (D) Pigment (D1) Rutile-type titanium dioxide (specific gravity 4, average particle size 0.45 μm) (D2) Kaolin clay (specific gravity 2.6, average particle size 0.8 μm) (D3) Organically modified bentonite (specific gravity 1.5, average particle size 0.5 μm) (solvent) Aliphatic hydrocarbon-containing non-aqueous solvent: mineral spirits (additives) Antifoaming agents, thickeners, etc.

[0059] <Preparation of Coating Material 1> ·Main ingredient manufacturing Main component 1 was prepared by mixing and stirring 48 parts by weight of component (A1), 12 parts by weight of component (A5), 25 parts by weight of component (D1), 10 parts by weight of solvent, and 5 parts by weight of additive. - Hardener manufacturing Curing agent 1 was prepared by mixing and stirring 5.8 parts by weight of component (B2), 3 parts by weight of component (C1), and 11.2 parts by weight of solvent. Preparation of coating material The base agent 1 (100 parts by weight) and the curing agent 1 (20 parts by weight) were mixed ([NCO] / [OH]=1.04) and stirred immediately before painting to obtain the coating material 1.

[0060] <Preparation of Coating Materials 2 to 16> Except for changing the formulation to that shown in Table 1, the components were mixed and stirred in the same manner as in Coating Material 1 to prepare the base resin and curing agent, which were then mixed immediately before painting to obtain the coating material.

[0061] [Table 1]

[0062] (Examples 1 to 11, Comparative Examples 1 to 5) The following evaluations [A] (evaluations [A-1], [A-2], and [A-3]) were carried out on the above-mentioned coating materials 1 to 16. The results are shown in Table 2.

[0063] <Preparation of test specimen [I]> An epoxy primer was applied to an aluminum plate (200 mm x 120 mm x 1 mm) to a dry film thickness of 30 μm, and the resulting substrate was dried for 8 hours under standard conditions (temperature 23 ° C, relative humidity 50%). Each coating material was applied to the substrate to a dry film thickness of 75 μm, and the substrate was dried for 7 days under standard conditions to prepare specimen [I].

[0064] Rating [A-1] (stain resistance) Each specimen [I] was sprayed with a carbon dispersion (1%), dried (60°C, 1 hour), and then washed with water. The difference in brightness (ΔL value) between the specimens before and after contamination was measured, and the stain resistance was evaluated. The ΔL value was measured using a TC-1800 color difference meter (manufactured by Tokyo Denshoku Co., Ltd.). The evaluation criteria are: AA: Lightness difference (ΔL value) less than 5 A: Lightness difference (ΔL value) is 5 or more and less than 10 B: Lightness difference (ΔL value) is 10 or more and less than 20 C: Lightness difference (ΔL value) is 20 or more and less than 30 D: Lightness difference (ΔL value) is 30 or more

[0065] Rating [A-2] (weather resistance) Each specimen [I] was exposed for 500 hours using an accelerated weathering tester (Metal Weather; manufactured by Daipla Wintes Co., Ltd.), after which the appearance of the surface of specimen [I] (gloss, color, lifting, peeling, cracking) was observed. The appearance change was compared with that of the specimen before exposure, and the evaluation was conducted on a 5-point scale (excellent: AA>A>B>C>D: poor), with "AA" indicating no change and "D" indicating loss of gloss, discoloration, lifting, peeling, or cracking.

[0066] <Preparation of test specimen [II]> The substrate to be painted was two 100mm x 300mm x 6mm slate boards placed side by side, with the connecting part between the boards (10mm wide) filled with a modified silicone sealant (resin component: alkoxysilyl group-containing polyether polymer, plasticizer content: less than 1% by weight). The coating material is applied to the entire surface of the substrate in a single application at a rate of 150 g / m 2 Spray paint twice (total amount of paint 300g / m 2 The specimen [II] was painted and dried for 7 days. All painting and drying were carried out under standard conditions.

[0067] Rating [A-3] (Tracking) Each specimen [II] was subjected to a total of 10 cycles of repeated heating and cooling tests, each cycle consisting of 18 hours of water immersion, 3 hours of rest at -20°C, and 3 hours of rest at 50°C. After this, the appearance of the coating at each part (connection part, plate part) was checked and the state of occurrence of defects (blistering, peeling, cracks, etc.) was evaluated. The evaluation was conducted on a 5-point scale (excellent: AA>A>B>C>D: poor), with "AA" being given for no defects and "D" being given for clear defects.

[0068] Coating materials 1 to 11 (Examples 1 to 11) provided coatings with sufficient stain resistance, as well as excellent weather resistance and conformability. On the other hand, coating materials 12 to 16 (Comparative Examples 1 to 5) did not provide sufficient results in the weather resistance and conformability evaluations.

[0069] Next, the following evaluation [B] (flex resistance evaluation) was carried out for the coating materials 1 to 11. The results are shown in Table 2.

[0070] <Preparation of test specimen [III]> Each coating material was applied to a tinplate (150mm x 50mm x 0.3mm) so that the dry film thickness was 75μm, and the coating was dried for 7 days to prepare a test specimen [III]. All coating and drying were carried out under standard conditions.

[0071] Rating [B] (crack resistance (flexibility)) The bending resistance of each specimen [III] was evaluated using the method specified in JIS K5600-5-1 "Bending resistance (cylindrical mandrel method)." The test was conducted under standard conditions using a Type 1 testing device, bending the specimen around a mandrel with a diameter of 2 mm, and visually inspecting the coating for cracks and peeling. The evaluation was conducted on a five-point scale (excellent: AA>A>B>C>D: poor), with no cracks being rated "AA" and cracks being rated "D."

[0072] In the coating materials 3 to 11 (Examples 3 to 11), coatings with excellent crack resistance (flexibility) were obtained.

[0073] [Table 2]

Claims

1. A coating material having a base agent and a curing agent, The base resin contains a hydroxyl group-containing resin (A), The curing agent contains a polyisocyanate compound (B) and a silicate compound (C), The hydroxyl group-containing resin (A) includes a non-aqueous dispersion type resin (a1) having a hydroxyl group value of 30 mgKOH / g or more and a soluble type resin (a2) having a hydroxyl group value of 30 mgKOH / g or more, The coating material is characterized in that the hydroxyl value of the non-aqueous dispersion type resin (a1) is larger than the hydroxyl value of the soluble type resin (a2).

2. 2. The coating material according to claim 1, wherein the hydroxyl-containing resin (A) contains a silicone component.

3. 3. The coating material according to claim 1, wherein the non-aqueous dispersion type resin (a1) contains a silicone component.

4. The coating material according to any one of claims 1 to 3, characterized in that the polyisocyanate compound (B) contains a polyisocyanate compound (b1) having an isocyanate group content of less than 14% by weight and a polyisocyanate compound (b2) having an isocyanate group content of 14% by weight or more.

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