Water-based coating material, coating film forming method, and topcoat material set

Abstract

The present invention provides an aqueous coating material that has excellent room-temperature curing properties and exhibits excellent performance in terms of crack resistance, weather resistance, etc. The aqueous coating material of the present invention is an aqueous coating material having room-temperature curing properties that contains an acrylic silicone resin emulsion (A) and a pigment (B), characterized in that the silica residual ratio in the resin solid content of the acrylic silicone resin emulsion (A) is 1 to 40 mass %, the acrylic silicone resin emulsion (A) has a glass transition temperature of 30°C or lower, and the acrylic silicone resin emulsion (A) contains, as monomers constituting the emulsion, two or more (meth)acrylic acid alkyl esters (s) having an alkyl group with 4 or more carbon atoms, and the glass transition temperature of a homopolymer of the (meth)acrylic acid alkyl esters (s) having an alkyl group with 4 or more carbon atoms is 0°C or lower.

Description

[Technical Field]

[0001] The present invention relates to a novel aqueous coating material, a coating film forming method, and a topcoat material set. [Background technology]

[0002] Conventionally, surfaces of buildings, civil engineering structures, etc. have been finished with coating materials. Such coating materials not only impart aesthetic appeal through various colors and textures, but also protect the substrate from wind, rain, direct sunlight, etc., and therefore are required to exhibit excellent weather resistance. In recent years, in consideration of their non-polluting and safety, the use of water-based coating materials using resin emulsions as binders has increased.

[0003] One method for improving the weather resistance of aqueous coating materials is to use an acrylic silicone resin emulsion as a binder. For example, Patent Document 1 describes an aqueous coating material containing a resin emulsion having a specific silicon content, acid value, and hydroxyl value, its crosslinking agent, a pigment, etc.

[0004] Incidentally, aqueous coating materials applied to buildings, civil engineering structures, and the like are required to have the ability to form and cure a film (room temperature curing ability) in a temperature range of approximately 5 to 40° C., since the coating work is carried out outdoors. However, the above-mentioned patent documents do not sufficiently consider room temperature curing ability, and when coating is carried out at room temperature, cracks may occur in the coating film (film), or the weather resistance of the coating film may become insufficient.

[0005] In particular, among the substrates that make up the framework of buildings, civil engineering structures, and the like, cement-based substrates such as concrete and mortar may crack over time due to the shrinkage of the substrate itself, the load on the substrate, etc. In addition, in building materials such as lightweight concrete boards, aerated concrete boards, and siding boards, the joints between the building materials tend to be easily displaced due to changes in temperature, humidity, etc. Water-based topcoat materials applied to buildings, civil engineering structures, etc., also require crack resistance for such coated surfaces. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 8-12930 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide an aqueous coating material that has excellent room temperature curing properties and can exhibit excellent performance in terms of crack resistance, weather resistance, etc.

[0008] The present invention has been made in view of the above-mentioned problems, and has as its object to provide a method for forming a coating that can exhibit excellent performance in terms of crack resistance, weather resistance, etc. [Means for solving the problem]

[0009] As a result of extensive research into achieving the above object, the inventors came up with the idea of ​​an aqueous coating material containing an acrylic silicone resin emulsion having a specific silica residual ratio and a specific resin composition, and a pigment, which led to the completion of the present invention.

[0010] As a result of intensive research into achieving the above-mentioned objective, the inventor came up with the idea of ​​a coating formation method in which a specific first topcoat material is applied, and then an acrylic silicone resin emulsion having a specific resin composition and a specific second topcoat material containing a pigment are applied, leading to the completion of the present invention.

[0011] That is, the present invention has the following features. 1. An aqueous coating material having room temperature curing properties, which contains an acrylic silicone resin emulsion (A) and a pigment (B), characterized in that the residual silica ratio in the resin solid content of the acrylic silicone resin emulsion (A) is 1 to 40 mass %, the glass transition temperature of the acrylic silicone resin emulsion (A) is 30°C or lower, and the acrylic silicone resin emulsion (A) contains, as a monomer, two or more types of (meth)acrylic acid alkyl ester (s) having an alkyl group with 4 or more carbon atoms, and the glass transition temperature of a homopolymer of the (meth)acrylic acid alkyl ester (s) having an alkyl group with 4 or more carbon atoms is 0°C or lower. In the present invention, "room temperature" refers to 5 to 40°C. 2. The aqueous coating material described in 1., characterized in that the (meth)acrylic acid alkyl ester (s) having an alkyl group with 4 or more carbon atoms includes a (meth)acrylic acid alkyl ester (s1) having a branched alkyl group with 5 or more carbon atoms. 3. The aqueous coating material according to 2., wherein the branched alkyl group contains a methyl group. 4. An aqueous coating material according to 1., characterized in that it contains a crosslinking agent (C), the acrylic silicone resin emulsion (A) has a reactive functional group, and the crosslinking agent (C) has a functional group capable of reacting with the reactive functional group. 5. A coating formation method in which a first topcoat material and a second topcoat material are applied to a surface to be coated in that order to form a topcoat material film, wherein the first topcoat material forms a film with an elongation rate of 20% or more at -10°C, the second topcoat material is an aqueous coating material described in any of 1. to 4., and the second topcoat material forms a film with an elongation rate at -10°C that is smaller than the elongation rate of the first topcoat material at -10°C. 6. The first topcoat material contains a resin emulsion and a pigment, and the monomer constituting the resin emulsion contains two or more types of (meth)acrylic acid alkyl ester (s) having an alkyl group with 4 or more carbon atoms, and the glass transition temperature of the homopolymer of the (meth)acrylic acid alkyl ester (s) having an alkyl group with 4 or more carbon atoms is 0°C or less. The coating formation method described in 5. 7. The method for forming a coating according to 6., wherein the (meth)acrylic acid alkyl ester (s) having an alkyl group having 4 or more carbon atoms includes a (meth)acrylic acid alkyl ester (s1) having a branched alkyl group having 5 or more carbon atoms. 8. The aqueous coating material according to 7, wherein the branched alkyl group contains a methyl group. 9.5. A topcoat material set consisting of the first topcoat material and the second topcoat material used in the coating formation method described above. [Effects of the Invention]

[0012] The aqueous coating material of the present invention has excellent room temperature curing properties and can exhibit excellent performance in terms of crack resistance, weather resistance, and the like.

[0013] According to the coating formation method of the present invention, a coating that exhibits excellent performance in terms of crack resistance, weather resistance, etc. can be formed. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an embodiment of the present invention will be described.

[0015] [Water-based coating material] The aqueous coating material of the present invention is characterized by containing a specific acrylic silicone resin emulsion (A) and a pigment (B). Such an aqueous coating material can form a colored coating film by room temperature curing. Specifically, the acrylic silicone resin emulsion (A) has a silica residual ratio of 1 to 40 mass% in the resin solid content, a glass transition temperature (hereinafter also referred to as "Tg") of 30°C or lower, and contains, as a monomer constituting the acrylic silicone resin emulsion (A), two or more (meth)acrylic acid alkyl esters (s) having an alkyl group with 4 or more carbon atoms, and the glass transition temperature of a homopolymer of the (meth)acrylic acid alkyl esters (s) having an alkyl group with 4 or more carbon atoms is 0°C or lower. In the present invention, the term "monomer" is a general term for compounds having a polymerizable unsaturated double bond (excluding compounds having a silicon atom).

[0016] Generally, a resin emulsion is prepared by emulsifying and dispersing a resin in an aqueous medium (a medium containing water). The glass transition temperature of a resin is a value calculated by Fox's formula based on the intrinsic Tg of each monomer constituting the resin (Tg of the homopolymer of each monomer) and the constituent ratio. In the present invention, an acrylic silicone resin emulsion (A) is used as the resin emulsion. The acrylic silicone resin emulsion (A) is obtained by emulsifying and dispersing an acrylic silicone resin in an aqueous medium. The glass transition temperature of the acrylic silicone resin emulsion (A) is a value calculated by the Fox formula based on the intrinsic Tg of each monomer constituting the acrylic silicone resin emulsion (A) and the constituent ratio. However, in the present invention, the alkoxysilane compound is excluded from the calculation of the Tg of the acrylic silicone resin emulsion (A).

[0017] <Component (A)> Generally, resin emulsions can be cured at room temperature by setting their glass transition temperature below room temperature (5 to 40°C). Acrylic silicone resin emulsions can also be cured at room temperature by setting their glass transition temperature below room temperature.

[0018] However, in aqueous coating materials that use an acrylic silicone resin emulsion containing a large amount of silicone components as a binder and further mix in a pigment, even if the glass transition temperature of the acrylic silicone resin emulsion is set low, problems such as cracks occurring in the coating film or insufficient weather resistance of the coating film are likely to occur.

[0019] The present invention is directed to such an aqueous coating material, which contains an acrylic silicone resin emulsion that satisfies the above-mentioned requirements as an essential component. The aqueous coating material of the present invention, which has such a specific composition, can exhibit excellent performance in terms of crack resistance, weather resistance, etc. Furthermore, the aqueous coating material of the present invention has a silica residual ratio of 1 to 40 mass% in the resin solids of the acrylic silicone resin emulsion (A), so it can demonstrate stable performance even when using a binder containing a high proportion of silicone components, thereby allowing for a relative reduction in petroleum-derived organic components and contributing to decarbonization. Furthermore, the aqueous coating material of the present invention has excellent weather resistance, which can extend the life of the coated object and reduce the total number of maintenance cycles, thereby contributing to decarbonization and other aspects.

[0020] The aqueous coating material of the present invention uses, as a binder, an acrylic silicone resin emulsion (A) (hereinafter referred to as "component (A)") having a silica residual ratio of 1 to 40 mass% in the resin solid content and a glass transition temperature of 30°C or lower.

[0021] As such component (A), a component (resin component) constituting the acrylic silicone resin can be used, which includes a monomer such as a (meth)acrylic acid alkyl ester including a (meth)acrylic acid alkyl ester (s) having an alkyl group with 4 or more carbon atoms, and an alkoxysilane compound. In the present invention, alkyl acrylates and alkyl methacrylates are collectively referred to as (meth)acrylic acid alkyl esters. In addition, in the present invention, "α to β" is synonymous with "α or more and β or less."

[0022] Examples of (meth)acrylic acid alkyl esters include methyl methacrylate (Tg: 105°C), ethyl methacrylate (Tg: 65°C), n-propyl methacrylate (Tg: 35°C), isopropyl methacrylate (Tg: 81°C), n-butyl methacrylate (Tg: 20°C), tert-butyl acrylate (Tg: 43°C), tert-butyl methacrylate (Tg: 107°C), isobutyl methacrylate (Tg: 53°C), n-pentyl acrylate (Tg: 22°C), cyclohexyl acrylate (Tg: 15°C), cyclohexyl methacrylate (Tg: 83°C), stearyl acrylate (Tg: 35°C), and hexadecyl acrylate (Tg: 3 (Meth)acrylic acid alkyl esters having a homopolymer Tg of 15°C or higher, such as methyl acrylate (Tg: 8°C), n-propyl acrylate (Tg: 3°C), n-lauryl acrylate (Tg: 10°C), n-propyl ...Ethyl acrylate (Tg: -20°C), isopropyl acrylate (Tg: -3°C), n-butyl acrylate (Tg: -54°C), isobutyl acrylate (Tg: -26°C), n-pentyl methacrylate (Tg: -5°C), isoamyl acrylate (Tg: -45°C), n-hexyl acrylate (Tg: -57°C), n-hexyl methacrylate (Tg: -5°C), 2-ethylhexyl acrylate (Tg: -70°C), 2-ethylhexyl methacrylate (Tg: -10°C), n-octyl acrylate (Tg: -65°C), 2-octyl acrylate Examples of (meth)acrylic acid alkyl esters having a homopolymer Tg of 0°C or less include (meth)acrylic acid alkyl esters having a homopolymer Tg of 0°C or less, such as acrylate (Tg: -44°C), isooctyl methacrylate (Tg: -45°C), isooctyl acrylate (Tg: -70°C), isononyl acrylate (Tg: -58°C), isodecyl acrylate (Tg: -60°C), isodecyl methacrylate (Tg: -41°C), tridecyl acrylate (Tg: -55°C), tridecyl methacrylate (Tg: -40°C), n-lauryl methacrylate (Tg: -65°C), and tetradecyl methacrylate (Tg: -72°C). These may be used alone or in combination of two or more, and the (meth)acrylic acid alkyl esters having a homopolymer Tg of 0°C or less include two or more.

[0023] Examples of the alkoxysilane compound include polymerizable unsaturated double bond-containing silane coupling agents such as γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, and vinyltriisopropoxysilane; epoxy group-containing silane coupling agents such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; N-2(aminoethyl)3-aminopropyltrimethoxysilane, N-2(aminoethyl)3-aminopropylmethyldimethoxysilane; Silane coupling agents (i) such as amino group-containing silane coupling agents, such as dimethylsilane, N-2(aminoethyl)3-aminopropyltriethoxysilane, N-2(aminoethyl)3-aminopropylmethyldiethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane; mercapto group-containing silane coupling agents, such as γ-mercaptopropyltrimethoxysilane; ureido group-containing silane coupling agents, such as 3-ureidopropyltriethoxysilane; chloroalkyl group-containing silane coupling agents, such as 3-chloropropyltrimethoxysilane; sulfide group-containing silane coupling agents, such as bis(triethoxysilylpropyl)tetrasulfide; and isocyanate group-containing silane coupling agents, such as 3-isocyanatepropyltriethoxysilane.

[0024] Tetrafunctional alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, tetra-n-butoxysilane, tetra-i-butoxysilane, tetra-t-butoxysilane, and tetraacetoxysilane; methyltrimethoxysilane, methyltriethoxysilane, methyltrippropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltrippropoxysilane, ethyltributoxysilane, propyltrimethoxysilane, propyltriethoxysilane, propyltrippropoxysilane, propyltributoxysilane, butyltrimethoxysilane, butyltriethoxysilane, butyltrippropoxysilane, butyltributoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltributoxysilane, methyltriacetoxysilane, phenyltriacetoxysilane, dimethyldimethylsilane, alkylalkoxysilanes such as tetrafunctional alkoxysilane, dimethyldiethoxysilane, dimethyldipropoxysilane, dimethyldibutoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diethyldipropoxysilane, diethyldibutoxysilane, dipropyldimethoxysilane, dipropyldiethoxysilane, dibutyldimethoxysilane, dibutyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, diphenyldibutoxysilane, dimethoxymethylphenylsilane, methylphenyldiethoxysilane, cyclohexylmethyldimethoxysilane, dimethyldiacetoxysilane, and diphenyldiacetoxysilane; or alkoxysilane-modified products obtained by modifying at least a portion of the alkoxyl groups of these tetrafunctional alkoxysilanes or alkylalkoxysilanes with a polyoxyalkylene group-containing compound, a fluorine-containing compound, or the like;

[0025] Examples include cyclic siloxanes (iii) such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, etc. These can be used alone or in combination of two or more.

[0026] The ratio of the alkoxysilane compound is preferably 2 to 100 parts by mass, more preferably 10 to 90 parts by mass, and even more preferably 20 to 85 parts by mass, relative to 100 parts by mass of the (meth)acrylic acid alkyl ester. Such a ratio of the alkoxysilane compound is suitable in terms of crack resistance, weather resistance, polymerization stability, etc.

[0027] Component (A) may contain other monomers (other monomers) as resin constituents. Examples of such other monomers include carboxyl group-containing monomers such as acrylic acid (Tg: 106°C), methacrylic acid (Tg: 185°C), itaconic acid (Tg: 100°C), and maleic acid (Tg: 130°C); aromatic monomers such as styrene (Tg: 100°C) and α-methylstyrene (Tg: 168°C); carbonyl group-containing monomers such as acrolein (Tg: 60°C) and diacetone acrylamide (Tg: 65°C); 2-hydroxyethyl acrylate (Tg: -15°C); hydroxyl group-containing monomers such as N,N-dimethylaminoethyl acrylate (Tg: 18°C), N,N-dimethylaminoethyl methacrylate (Tg: 18°C), N,N-diethylaminoethyl methacrylate (Tg: 20°C), and N,N-dimethylaminoethyl acrylate (Tg: 20°C). Containing monomers: amide group-containing monomers such as acrylamide (Tg: 179°C) and N,N-dimethylaminopropylacrylamide (Tg: 134°C); nitrile group-containing monomers such as acrylonitrile (Tg: 125°C); epoxy group-containing monomers such as glycidyl methacrylate (Tg: 46°C); oxazoline group-containing monomers such as 2-isopropenyl-2-oxazoline (Tg: 100°C); 2-[2'-hydroxy-5'-methacryloyloxyethylphenyl]-2H-benzo Examples of suitable additives include ultraviolet absorbers containing ethylenically unsaturated double bonds, such as triazole (Tg: 100°C); light stabilizers containing ethylenically unsaturated double bonds, such as 4-methacryloyloxy-1,2,2,6,6-pentamethylpiperidine (Tg: 130°C); and sulfonic acid-containing vinyl monomers, acid anhydrides, chlorine-containing monomers, fluorine-containing monomers, alkylene glycol monoallyl ethers, vinyl acetate, vinyl propionate, vinyl ethers, ethylene, propylene, isobutylene, etc. These can be used alone or in combination of two or more.

[0028] The ratio of the other monomer is preferably 0.1 to 20 parts by mass, more preferably 0.2 to 15 parts by mass, and even more preferably 0.3 to 10 parts by mass, relative to 100 parts by mass of the (meth)acrylic acid alkyl ester. By using the other monomer within such a range, various functions (for example, crosslinkability, stability, dispersibility, etc.) can be imparted.

[0029] In the present invention, the monomer constituting component (A) can be a monomer obtained from a biological resource, i.e., a biomass-based monomer. The introduction of such a biomass-based monomer increases the biomass content of component (A) and thus the aqueous coating material, thereby enabling the reduction of the amount of petroleum-derived compounds used. The use of such materials can also contribute to decarbonization. Examples of biomass-based monomers that can be used include monomers produced using biologically derived alcohols, organic acids, hydrocarbons, etc. Since many (meth)acrylic acid alkyl esters having an alkyl group with four or more carbon atoms have been put to practical use as biomass-based monomers, the present invention can effectively obtain an aqueous coating material with a high biomass content.

[0030] Component (A) can be produced by polymerizing the resin components described above. Any known polymerization method can be used, including conventional emulsion polymerization, soap-free emulsion polymerization, feed emulsion polymerization, seed emulsion polymerization, and multistage emulsion polymerization. Multistage emulsion polymerization can be carried out by a two-stage or three-stage or more emulsion polymerization method. During polymerization of component (A), for example, emulsifiers, initiators, dispersants, polymerization inhibitors, polymerization retarders, buffers, chain transfer agents, pH adjusters, and the like may be used.

[0031] Of these, as the emulsifier, various surfactants that can be used in emulsion polymerization can be used, and these may be reactive types (reactive surfactants) that have a polymerizable unsaturated double bond. Examples of emulsifiers that can be used include anionic surfactants, nonionic surfactants, cationic surfactants, and amphoteric surfactants. Polymer emulsifiers such as polyurethane resins, polyacrylic acid resins, polyvinyl alcohol, and polyvinylpyrrolidone can also be used. These emulsifiers can be used alone or in combination.

[0032] The proportion of the emulsifier is preferably 0.3 to 10% by mass, more preferably 0.5 to 5% by mass, based on the total amount of the resin constituent components.

[0033] The component (A) in the present invention contains, as a monomer constituting an acrylic silicone resin, two or more types of (meth)acrylic acid alkyl ester (s) (hereinafter also referred to as "component (s)") having an alkyl group with 4 or more carbon atoms and having a homopolymer Tg of 0°C or less (preferably -15°C or less, more preferably -30°C or less).

[0034] Examples of the component (s) include n-butyl acrylate (Tg: -54°C), isobutyl acrylate (Tg: -26°C), n-pentyl methacrylate (Tg: -5°C), isoamyl acrylate (Tg: -45°C), n-hexyl acrylate (Tg: -57°C), n-hexyl methacrylate (Tg: -5°C), 2-ethylhexyl acrylate (Tg: -70°C), 2-ethylhexyl methacrylate (Tg: -10°C), n-octyl acrylate (Tg: -65°C), 2-octyl Examples of suitable acrylates include butyl acrylate (Tg: -44°C), isooctyl methacrylate (Tg: -45°C), isooctyl acrylate (Tg: -70°C), isononyl acrylate (Tg: -58°C), isodecyl acrylate (Tg: -60°C), isodecyl methacrylate (Tg: -41°C), tridecyl acrylate (Tg: -55°C), tridecyl methacrylate (Tg: -40°C), n-lauryl methacrylate (Tg: -65°C), and tetradecyl methacrylate (Tg: -72°C). These can be used in combination of two or more (preferably 2 to 5 types, more preferably 2 to 4 types, and even more preferably 2 to 3 types). Among these, for example, isoamyl acrylate, n-hexyl acrylate, n-octyl acrylate, 2-octyl acrylate, n-lauryl methacrylate, etc. are also suitable in that they can be used as biomass-based monomers.

[0035] In the present invention, component (A) has such a specific structure, and is therefore able to exhibit excellent performance in terms of crack resistance, weather resistance, etc. The reasons for such performance are not limited to the following, but it is believed that the presence of two or more alkyl groups with different chemical structures as described above in component (s) contributes to improved film-forming properties and imparted strength to the formed coating due to the action of those alkyl groups.

[0036] The number of carbon atoms in the alkyl group in component (s) is 4 or more, preferably 4 to 12, more preferably 4 to 10, and even more preferably 5 to 8. In the present invention, by using two or more types of component (s) having such carbon numbers, excellent performance can be exhibited in terms of crack resistance, weather resistance, etc.

[0037] The proportion of the (s) component is preferably 20 to 80% by mass, more preferably 30 to 70% by mass, of the total amount of (meth)acrylic acid alkyl ester. Furthermore, of two or more (s) components, the proportion of the (s) component with the highest proportion in the total amount of the (s) components is preferably 20 to 95% by mass, more preferably 25 to 85% by mass, and even more preferably 30 to 70% by mass. Such an embodiment of the (s) component is suitable in terms of room temperature curability, crack resistance, weather resistance, etc.

[0038] In the present invention, the component (A) preferably comprises at least one component (s) that is a (meth)acrylic acid alkyl ester (s1) having a branched alkyl group with 5 or more carbon atoms (hereinafter also referred to as "component (s1)"). The alkyl group in component (s1) preferably has 5 or more carbon atoms, more preferably 5 to 12, even more preferably 5 to 10, and particularly preferably 5 to 8. In the present application, "branched alkyl group with 5 or more carbon atoms" refers to an alkyl group that has a main chain and side chains, and the total number of carbon atoms in the main chain and side chains is 5 or more. Examples of the (s1) component include isoamyl acrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, 2-octyl acrylate, isooctyl methacrylate, isooctyl acrylate, isononyl acrylate, isodecyl acrylate, and isodecyl methacrylate. The (A) component preferably contains at least one (s1) component, and more preferably two or more (s1) components, as a monomer constituting the acrylic silicone resin. By including the (s1) component in the (A) component, the (A) component can exhibit even more excellent performance in terms of crack resistance, blister resistance, weather resistance, and the like. The reasons for this performance include, but are not limited to, the effect of the branched alkyl group, which provides strength to the formed coating.

[0039] The proportion of component (s1) in the total amount of component (s) is preferably 20% by mass or more, more preferably 25% by mass or more, and even more preferably 30 to 100% by mass. Such an embodiment of component (s1) is suitable for improving physical properties such as crack resistance, blister resistance, and weather resistance.

[0040] In the present invention, the component (A) is preferably a (meth)acrylic acid alkyl ester (s11) (hereinafter also referred to as "component (s11)") in which at least one of the components (s) has a branched alkyl group having 5 or more carbon atoms, and the branched alkyl group has a methyl group. The number of carbon atoms in the alkyl group in component (s11) is preferably 5 or more, more preferably 5 to 12, even more preferably 5 to 10, and particularly preferably 5 to 8. Examples of the (s11) component include isoamyl acrylate, 2-octyl acrylate, isooctyl methacrylate, isooctyl acrylate, isononyl acrylate, isodecyl acrylate, and isodecyl methacrylate. It is desirable that the (A) component contain at least one (s11) component as a monomer constituting the acrylic silicone resin, and more desirably two or more (s11) components. When the (A) component contains the (s11) component, it can exhibit even more excellent performance in terms of crack resistance, blister resistance, weather resistance, and the like. In particular, the (s11) component significantly contributes to water resistance, blister resistance, and the like in the early stages of film formation. The reasons for this performance include, but are not limited to, the effect of the branched alkyl group containing a methyl group, which imparts strength to the formed coating early on.

[0041] The proportion of component (s11) in the total amount of component (s) is preferably 20% by mass or more, more preferably 25% by mass or more, and even more preferably 30 to 100% by mass. If component (s11) is in this form, it is suitable in terms of improving physical properties such as crack resistance, blister resistance, and weather resistance.

[0042] In the present invention, component (A) has a silica residual ratio of 1 to 40 mass%, preferably 5 to 35 mass%, and more preferably 10 to 30 mass% of the resin solid content. When the silica residual ratio of component (A) is within the above range, the silicon component is contained in a large amount, and excellent weather resistance can be exhibited while ensuring physical properties such as crack resistance. If the silica residual ratio is below the above lower limit, it becomes difficult to obtain sufficient physical properties such as weather resistance, while if the silica residual ratio is above the above upper limit, crack resistance and other properties become insufficient, and weather resistance is also likely to be disadvantageous.

[0043] The residual silica ratio is the mass ratio of silica (SiO2) that remains when a component with Si-O bonds is baked at 900°C. Generally, alkoxysilanes react with water to undergo a hydrolysis reaction, turning into silanols, which then undergo condensation reactions between silanols and between silanols and alkoxy. When this reaction is carried to its ultimate state, silica (SiO2) is formed. These reactions are expressed by the following general formula (reaction formula): RO(Si(OR)2O) n R+(n+1)H2O→nSiO2+(2n+2)ROH The residual silica ratio is calculated based on this reaction formula and is the amount of remaining silica component.

[0044] In component (A), the type and ratio of the alkoxysilane compound in the resin constituents can be set so as to satisfy the above-mentioned silica residual ratio. As shown in the general formula above, n moles of Si generate n moles of SiO2. Based on this, the silica residual ratio in component (A) can be set by the silicon atom ratio per molecule of the alkoxysilane compound used and its blending ratio. The alkoxysilane compound in component (A) may be, for example, (1) an embodiment containing a silane coupling agent (i), (2) an embodiment containing an alkoxysilane (ii) and / or a cyclic siloxane (iii), or (3) an embodiment containing a silane coupling agent (i) and an alkoxysilane (ii) and / or a cyclic siloxane (iii), etc. Of these, the above embodiments (2) or (3) (particularly embodiment (3)) are preferred in terms of increasing the proportion of the silicon component, etc. In the above embodiment (3), the proportion of the silane coupling agent (i) in the total amount of the silane coupling agent (i), the alkoxysilanes (ii), and the cyclic siloxanes (iii) is preferably 1 to 30 mass%, more preferably 2 to 25 mass%.

[0045] The glass transition temperature (Tg) of component (A) is 30°C or lower, preferably -50°C to 25°C, more preferably -40°C to 20°C, and even more preferably -30°C to 15°C. Having a Tg of component (A) within the above range is preferable in terms of room temperature curing ability, cracking resistance, weather resistance, stain resistance, and the like. If the Tg exceeds the above upper limit, it becomes difficult to obtain sufficient physical properties such as room temperature curing ability and cracking resistance. In component (A), the types and ratios of monomers used as resin constituents can be set so as to satisfy the above glass transition temperature.

[0046] The average particle size of component (A) is preferably 300 nm or less, more preferably 20 to 250 nm, and even more preferably 50 to 200 nm. The average particle size referred to here is a value measured by dynamic light scattering.

[0047] The component (A) in the present invention can be in a form in which multiple resin phases are mixed, so long as the Tg is 30° C. or less. Such a component (A) may, for example, contain a hard resin phase with a Tg of 15° C. or more and a soft resin phase with a Tg of 0° C. or less, and the Tg of the entire resin constituting component (A) may be 30° C. or less. Of these, the hard resin phase can be obtained by polymerizing one or more (preferably two or more) of the above-mentioned monomers so that the Tg is 15°C or higher (more preferably 30°C or higher, and even more preferably 50°C or higher). The hard resin phase desirably contains, as a resin constituent, a (meth)acrylic acid alkyl ester having a homopolymer Tg of 15° C. or higher (more preferably 30° C. or higher, and even more preferably 50° C. or higher).

[0048] The soft resin phase can be obtained by polymerizing two or more of the above-mentioned monomers so that the Tg is 0° C. or lower (more preferably −15° C. or lower, and even more preferably −30° C. or lower). The soft resin phase desirably contains, as a resin constituent, a (meth)acrylic acid alkyl ester having a homopolymer Tg of 0° C. or lower (more preferably −15° C. or lower, and even more preferably −30° C. or lower).

[0049] The ratio of the hard resin phase to the soft resin phase in component (A) may be set within a range in which the Tg of the entire resin is 30°C or less. The ratio of the hard resin phase is preferably 10 to 90 mass%, more preferably 20 to 80 mass%, and even more preferably 30 to 70 mass%, based on the resin solid content of component (A). The ratio of the soft resin phase is preferably 10 to 90 mass%, more preferably 20 to 80 mass%, and even more preferably 30 to 70 mass%, based on the resin solid content of component (A). Such mass ratios make it easier to more stably achieve the effects of the present invention described above. Note that component (A) may, for example, have an embodiment in which it contains two or more hard resin phases with different Tg's, or an embodiment in which it contains two or more soft resin phases with different Tg's. Furthermore, component (A) may have an embodiment in which it contains a resin phase different from the hard resin phase and soft resin phase described above (for example, a resin phase having a Tg intermediate between the hard resin phase and the soft resin phase (Tg greater than 0°C and less than 15°C)).

[0050] When component (A) contains a hard resin phase and a soft resin phase, as long as the above-mentioned conditions are met, the hard resin phase and the soft resin phase may coexist in the same emulsion particle, or may exist in separate emulsion particles.Specifically, for example, it can be (I) a multilayer structure type acrylic silicone resin emulsion containing a hard resin phase and a soft resin phase in the same emulsion particle, (II) a mixture of an acrylic silicone resin emulsion containing a hard resin phase and an acrylic silicone resin emulsion containing a soft resin phase, etc.

[0051] <(B) component> Pigment (B) (hereinafter also referred to as "component (B)") is a component that contributes to at least one of color development, hiding power, gloss, aesthetics, strength, etc. Examples of component (B) that can be used include color pigment (B1) (hereinafter also referred to as "component (B1)") and extender pigment (B2) (hereinafter also referred to as "component (B2)").

[0052] The content of component (B) is preferably 5 to 650 parts by mass, more preferably 10 to 500 parts by mass, even more preferably 15 to 300 parts by mass, and particularly preferably 20 to 200 parts by mass, per 100 parts by mass of the solid content of component (A).

[0053] Examples of the color pigment (B1) include titanium oxide, zinc oxide, carbon black, graphite, black iron oxide, iron-manganese composite oxide, iron-copper-manganese composite oxide, iron-chromium composite oxide, iron-chromium-cobalt composite oxide, copper-chromium composite oxide, copper-manganese-chromium composite oxide, copper-magnesium composite oxide, bismuth-manganese composite oxide, red iron oxide, molybdate orange, permanent red, permanent carmine, anthraquinone red, perylene red, quinacridone red, yellow iron oxide, titanium yellow, fast yellow, benzimidazolone yellow, chrome green, cobalt green, phthalocyanine green, ultramarine blue, Prussian blue, cobalt blue, phthalocyanine blue, quinacridone violet, dioxazine violet, aluminum pigments, and pearl pigments. These can be used alone or in combination of two or more.

[0054] The average particle size of the component (B1) is preferably 2 μm or less, and more preferably 0.01 to 1 μm. The average particle size of the pigment (B) is a value measured by a laser diffraction particle size distribution analyzer.

[0055] The content of component (B1) is preferably 250 parts by mass or less, more preferably 5 to 200 parts by mass, and even more preferably 10 to 150 parts by mass, per 100 parts by mass of the solid content of component (A). A content of component (B1) within this range is suitable in terms of the color development, hiding power, aesthetic appearance, etc. of the coating film, and is also advantageous in terms of manifesting the effects of the present invention.

[0056] Examples of the extender pigment (B2) include heavy calcium carbonate, light calcium carbonate, kaolin, clay, aluminum silicate, calcined clay, calcined kaolin, china clay, diatomaceous earth, hydrous finely powdered silicic acid, silica gel, zeolite, sodium sulfate, allophane, talc, mica, barite powder, barium sulfate, precipitated barium sulfate, barium carbonate, magnesium carbonate, silica powder, resin beads, aluminum hydroxide, porous calcium carbonate, siliceous shale, vermiculite, perlite, Oya stone powder, activated clay, activated carbon, shirasu balloon, etc. These can be used alone or in combination of two or more.

[0057] The average particle size of the extender pigment is preferably 0.1 to 100 μm, more preferably 0.3 to 50 μm.

[0058] The content of component (B2) is preferably 400 parts by mass or less, more preferably 10 to 350 parts by mass, even more preferably 15 to 300 parts by mass, and particularly preferably 20 to 200 parts by mass, per 100 parts by mass of the solid content of component (A). A content of component (B2) within this range is favorable in terms of the strength and aesthetics of the coating film, and is also advantageous in terms of achieving the effects of the present invention. Furthermore, the gloss of the coating can be set to a low gloss (e.g., semi-gloss, 30% gloss, matte, etc.).

[0059] <(C) component> In the aqueous coating material of the present invention, a crosslinking agent (C) (hereinafter also referred to as "component (C)") can be mixed with component (A). In this case, component (A) can be an acrylic silicone resin emulsion having a reactive functional group, and component (C) can be a crosslinking agent having a functional group capable of reacting with the reactive functional group. When such a component is present, in addition to the effect of component (s) described above, the crosslinking reaction between component (A) and the crosslinking agent is thought to impart strength to the coating during and after film formation, thereby improving physical properties such as crack resistance, blister resistance, and weather resistance.

[0060] Suitable examples of the component (C) include water-soluble crosslinking agents, water-dispersible crosslinking agents, and self-emulsifying crosslinking agents.

[0061] In the components (A) and (C), examples of reactive functional groups that can be used in such crosslinking reactions include one or more selected from the group consisting of a carboxyl group, a carbodiimide group, an epoxy group, an aziridine group, an oxazoline group, a hydroxyl group, an isocyanate group, a carbonyl group, a hydrazide group, an epoxy group, an amino group, and an alkoxysilyl group. In components (A) and (C), such reactive functional groups may be used in combination. Examples of the combination of reactive functional groups include a carboxyl group and a carbodiimide group, a carboxyl group and an epoxy group, a carboxyl group and an oxazoline group, a carboxyl group and an aziridine group, a hydroxyl group and an isocyanate group, a carbonyl group and a hydrazide group, an epoxy group and an amino group, and an alkoxysilyl group. One or more of these can be used. Suitable reactive functional groups in component (A) include, for example, carboxyl groups, carbonyl groups, and alkoxysilyl groups.

[0062] Specifically, when component (A) has a carboxyl group, component (C) can be, for example, a compound having one or more reactive functional groups selected from a carbodiimide group, an epoxy group, an oxazoline group, etc. Among these, examples of crosslinking agents having a carbodiimide group include those described in JP-A-10-60272, JP-A-10-316930, JP-A-11-60667, JP-A-2000-7642, JP-A-2000-119539, JP-A-2000-319351, JP-A-2013-112755, JP-A-2016-196612, JP-A-2016-196613, WO2017 / 6950, etc. Examples of crosslinking agents having an epoxy group include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyhydroxyalkane polyglycidyl ether, and sorbitol polyglycidyl ether. Examples of crosslinking agents having an oxazoline group include resins obtained by copolymerizing a polymerizable oxazoline compound, such as 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, or 2-isopropenyl-2-oxazoline, with a monomer copolymerizable with the compound. These compounds can be used alone or in combination of two or more.

[0063] The component (A) having a carboxyl group can be obtained by using a carboxyl group-containing monomer such as acrylic acid, methacrylic acid, itaconic acid, or maleic acid as a resin constituent.

[0064] When component (A) has a carbonyl group, for example, a compound having a hydrazide group can be used as component (C). Examples of crosslinking agents having a hydrazide group include malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, and maleic acid dihydrazide. These can be used alone or in combination of two or more.

[0065] The component (A) having a carbonyl group can be obtained by using a carbonyl group-containing monomer such as acrolein or diacetone acrylamide as a resin constituent.

[0066] When component (A) has an alkoxysilyl group, for example, a compound having an alkoxysilyl group can be used as component (C). Examples of crosslinking agents having an alkoxysilyl group include the silane coupling agents and alkoxysilane compounds such as alkoxysilanes described above for component (A). These can be used alone or in combination of two or more.

[0067] The proportion of component (C) is preferably 0.05 to 50 parts by mass, more preferably 0.1 to 20 parts by mass, calculated as solid content, per 100 parts by mass of the resin solid content of component (A).Such a proportion can sufficiently improve crack resistance, blister resistance, weather resistance, etc.

[0068] In addition to the above-mentioned components, various additives can also be mixed into the aqueous coating material of the present invention. Examples of such additives include pigment dispersants, viscosity modifiers, leveling agents, coupling agents, wetting agents, film-forming aids, plasticizers, antifreeze agents, pH adjusters, preservatives, antifungal agents, anti-algae agents, antibacterial agents, antifoaming agents, adsorbents, deodorizers, UV absorbers, light stabilizers, hydrophilizing agents, antioxidants, catalysts, solvents, and water. These can be used alone or in combination as needed.

[0069] Of these, the pigment dispersant is a component that contributes to stabilizing the dispersion of the component (B) and enabling the component (B) to exhibit its performance.

[0070] As the pigment dispersant, one or more commercially available or known dispersants can be used, and for example, those having a resin skeleton such as a styrene-maleic acid copolymer resin, a polyurethane resin, a polyester resin, or an acrylic resin can be used.

[0071] The pigment dispersant in the aqueous coating material of the present invention is preferably a pigment dispersant having an acid group and / or a basic group, which can improve the dispersion stability of component (B). Furthermore, in general, aqueous coating materials that use an acrylic silicone resin emulsion containing a large amount of silicone components as a binder are prone to problems such as cracks in the coating or insufficient weather resistance, due to the pigment dispersant excessively promoting the reaction of the silicone components. However, in the present invention, even when such a pigment dispersant is used, by employing component (A) having the above-mentioned specific resin structure, it is possible to exhibit excellent performance in terms of crack resistance, weather resistance, etc.

[0072] Examples of acid groups include carboxy groups, sulfonic acid groups, and phosphate groups. Examples of basic groups include primary amino groups, secondary amino groups, tertiary amino groups, and quaternary ammonium salt groups. Component (C) can have one or more of these acid groups or basic groups. Suitable examples of component (C) include polycarboxylic acid dispersants such as polyacrylic acid, polymethacrylic acid, and styrene-maleic acid copolymer resins; sulfonic acid dispersants such as lignin sulfonic acid and naphthalene sulfonic acid; phosphate dispersants such as phosphate ester compounds; and polymer dispersants having an acid value and / or an amine value.

[0073] The content of the component (C) is preferably 0.01 to 20 parts by mass, and more preferably 0.1 to 10 parts by mass, calculated as solid content, per 100 parts by mass of the solid content of the component (A).

[0074] <(D) component> In addition to the above components, the aqueous coating material of the present invention can be used by mixing an ether or ester solvent (D) (hereinafter also referred to as "component (D)"). Of component (D), ether solvents are solvents having an ether bond in the molecule, and ester solvents are solvents having an ester bond in the molecule. In the present invention, component (D) can include an ether or ester solvent (D1) (hereinafter also referred to as "component (D1)") having a water solubility of 0.5 to 50 g / 100 g H2O. Ether solvents having a water solubility of 0.5 to 50 g / 100 g H2O and / or ester solvents having a water solubility of 0.5 to 50 g / 100 g H2O can be used. By including such component (D1), the aqueous coating material of the present invention can exhibit superior performance in terms of crack resistance, weather resistance, etc. When the aqueous coating material is a glossy type, gloss, etc. can also be improved. In the present invention, the solubility in water refers to the maximum mass (g) that can be dissolved in 100 g of water. The measurement temperature was 20°C.

[0075] As the component (D1), an ether solvent or an ester solvent having a water solubility within the above range can be used. Specific examples of the compound include ethylene glycol monohexyl ether (solubility in water: 0.99 g / 100 gH2O, boiling point: 208°C), propylene glycol phenyl ether (solubility in water: 1 g / 100 gH2O, boiling point: 243°C), ethylene glycol monobutyl ether acetate (solubility in water: 1.1 g / 100 gH2O, boiling point: 188°C), di ... Ethylene glycol monohexyl ether (solubility in water 1.7g / 100gH2O, boiling point 258°C), ethylene glycol monophenyl ether (solubility in water 2.6g / 100gH2O, boiling point 245°C), tripropylene glycol monobutyl ether (solubility in water 3g / 100gH2O, boiling point 274°C), diethylene glycol monophenyl ether (solubility in water 3.4g / 100gH2O, boiling point 283°C), dipropylene glycol monobutyl ether (solubility in water 5g / 100gH2O, boiling point 229°C), propylene glycol monobutyl ether (solubility in water 6g / 100gH2O, boiling point 170°C), diethylene glycol monobutyl ether acetate (solubility in water 6.5g / 100gH2O, boiling point 247°C), propylene glycol diacetate (solubility in water 8g / 100gH2O, boiling point 161°C), propylene glycol monomethyl ether acetate (solubility in water 16g / 100gH2O, boiling point 146°C), dipropylene glycol monopropyl ether (solubility in water 19g / 100gH2O, boiling point 212°C), dipropylene glycol monomethyl ether acetate (solubility in water 19g / 100gH2O, boiling point 209°C), ethylene glycol diethyl ether (solubility in water 20g / 100gH2O, boiling point 121°C), ethylene glycol monoethyl ether acetate (solubility in water 23g / 100gH2O, boiling point 156°C), etc. These can be used alone or in combination of two or more.

[0076] The solubility of component (D1) in water is 0.5 to 50 g / 100 g H2O, preferably 0.8 to 25 g / 100 g H2O, and more preferably 1 to 10 g / 100 g H2O. Furthermore, component (D1) preferably has a boiling point of 150°C or higher, more preferably 200°C or higher, and even more preferably 220°C or higher. Component (D1) that satisfies these physical property values ​​is suitable for achieving the effects of the present invention. The reasons why component (D1) exhibits the effects of the present invention are not limited to the following, but are presumed to be due to the fact that component (D1) has intermediate properties between hydrophobicity and hydrophilicity, and that these properties increase its affinity with the acrylic component and the silicone component. As the component (D1), those having a hydrophobic group with 4 or more carbon atoms are preferred, those having a hydrophobic group with 6 or more carbon atoms are more preferred, and those having a phenyl group are particularly suitable.

[0077] The content of component (D1) is preferably 1 to 40 parts by mass, more preferably 2 to 30 parts by mass, even more preferably 3 to 25 parts by mass, and particularly preferably 4 to 20 parts by mass, per 100 parts by mass of the solid content of component (A). If the content of component (D1) is within this range, even more excellent performance can be exhibited in room temperature curing properties, cracking resistance, weather resistance, etc.

[0078] In the present invention, the component (D) may contain two or more types of component (D1). For example, it is possible to employ an embodiment in which two types of component (D1) whose difference in water solubility is preferably 0.5 to 15 g / 100 g H2O (more preferably 0.8 to 10 g / 100 g H2O, and even more preferably 1 to 5 g / 100 g H2O) are contained. Such an embodiment is suitable for improving the gloss effect of the present invention.

[0079] In the present invention, the component (D) may include, in addition to the component (D1) described above, an ether or ester solvent (D2) (hereinafter also referred to as "component (D2)") having a solubility in water of more than 50 g / 100 g H2O. As the component (D2), an ether solvent having a solubility in water of more than 50 g / 100 g H2O and / or an ester solvent having a solubility in water of more than 50 g / 100 g H2O can be used. Specific examples of the compound include ethylene glycol monomethyl ether (solubility in water of ∞, boiling point 125°C), ethylene glycol monoethyl ether (solubility in water of ∞, boiling point 135°C), ethylene glycol monopropyl ether (solubility in water of ∞, boiling point 150°C), ethylene glycol monoisopropyl ether (solubility in water of ∞, boiling point 143 ... Ethylene glycol monobutyl ether (solubility in water: ∞, boiling point: 171°C), ethylene glycol monoisobutyl ether (solubility in water: ∞, boiling point: 161°C), ethylene glycol monotertiary butyl ether (solubility in water: ∞, boiling point: 153°C), ethylene glycol monomethyl ether acetate (solubility in water: ∞, boiling point: 145°C), ethylene glycol monoethyl ether acetate (solubility in water: ∞, boiling point: 156°C), ethylene glycol dimethyl ether (solubility in water: ∞, boiling point: 85°C), diethylene glycol monomethyl ether (solubility in water: ∞, boiling point: 85°C), Diethylene glycol monoethyl ether (solubility in water is infinite, boiling point 194°C), diethylene glycol monobutyl ether (solubility in water is infinite, boiling point 230°C), diethylene glycol monoisobutyl ether (solubility in water is infinite, boiling point 220°C), diethylene glycol monoethyl ether acetate (solubility in water is infinite, boiling point 217°C), diethylene glycol dimethyl ether (solubility in water is infinite, boiling point 162°C), diethylene glycol diethyl ether (solubility in water is infinite, boiling point 189°C), triethylene glycol monoethyl ether propylene glycol monomethyl ether (solubility in water: infinite, boiling point: 249°C), triethylene glycol monobutyl ether (solubility in water: infinite, boiling point: 271°C), triethylene glycol monoethyl ether (solubility in water: infinite, boiling point: 255°C), propylene glycol monomethyl ether (solubility in water: infinite, boiling point: 120°C), propylene glycol monoethyl ether (solubility in water: infinite, boiling point: 133°C), propylene glycol monopropyl ether (solubility in water: infinite, boiling point: 150°C), dipropylene glycol monomethyl ether (solubility in water: infinite, boiling point: 190°C),Examples include dipropylene glycol dimethyl ether (solubility in water: 53 g / 100 g H2O, boiling point: 175°C), tripropylene glycol monomethyl ether (solubility in water: infinity, boiling point: 242°C), and butylene glycol monomethyl ether (solubility in water: infinity, boiling point: 161°C). These can be used alone or in combination of two or more.

[0080] The solubility of component (D2) in water is greater than 50 g / 100 g H2O, preferably ∞. Furthermore, component (D2) preferably has a boiling point of 150° C. or higher. Component (D2) that satisfies these physical properties is suitable for improving the effects of the present invention.

[0081] In the present invention, the component (D) may include, in addition to the component (D1) described above, an ether or ester solvent (D3) (hereinafter also referred to as "component (D3)") having a solubility in water of less than 0.5 g / 100 g H2O. As the component (D3), an ether solvent having a solubility in water of less than 0.5 g / 100 g H2O and / or an ester solvent having a solubility in water of less than 0.5 g / 100 g H2O can be used. Specific examples of the compound include diethylene glycol dibutyl ether (solubility in water of 0.3 g / 100 g H2O, boiling point of 255°C), diethylene glycol mono-2-ethylhexyl ether (solubility in water of 0.3 g / 100 g H2O, boiling point of 272°C), ethylene glycol mono-2-ethylhexyl ether (solubility in water of 0.3 g / 100 g H2O, boiling point of 272°C), and ethylene glycol mono-2-ethylhexyl ether (solubility in water of 0.3 g / 100 g H2O, boiling point of 272°C). Examples include 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (solubility in water: 0.09 g / 100 g H2O, boiling point: 255°C), and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (solubility in water: 0.04 g / 100 g H2O, boiling point: 282°C). These can be used alone or in combination of two or more.

[0082] The solubility of component (D3) in water is less than 0.5 g / 100 g H2O, preferably 0.4 g / 100 g H2O or less, and more preferably 0.01 to 0.4 g / 100 g H2O. Furthermore, component (D3) preferably has a boiling point of 200°C or higher, more preferably 220°C or higher. A component (D3) that satisfies these physical properties is suitable for improving the effects of the present invention.

[0083] In the present invention, the component (D) can be in the following forms: a form containing the component (D1), a form containing the component (D1) and the component (D2), a form containing the component (D1) and the component (D3), a form containing the component (D1), the component (D2), and the component (D3), etc. In each of these forms, two or more types of the component (D1) can be included.

[0084] When component (D2) is included as component (D), the amount of component (D2) is preferably 0.5 to 30 parts by mass, more preferably 1 to 20 parts by mass, per 100 parts by mass of the solid content of component (A). In this case, the mass ratio of components (D1) to (D2) ((D1):(D2)) is preferably 95:5 to 10:90, more preferably 90:10 to 10:90, and even more preferably 80:20 to 20:80. Furthermore, when component (D3) is included as component (D), the amount of component (D3) is preferably 1 to 30 parts by mass, more preferably 2 to 30 parts by mass, per 100 parts by mass of the solid content of component (A). In this case, the mass ratio of the (D1) component to the (D3) component ((D1):(D3)) is preferably 95:5 to 5:95, more preferably 90:10 to 10:90, and even more preferably 80:20 to 20:80. Such an embodiment is suitable in terms of improving the effects of the present invention.

[0085] In addition to the above-mentioned components, the aqueous coating material of the present invention may also contain other components such as a resin emulsion and a water-soluble resin other than component (A). Examples of resin emulsions other than component (A) include acrylic resin emulsions, urethane resin emulsions, fluororesin emulsions, epoxy resin emulsions, etc. Acrylic silicone resin emulsions other than component (A) can also be used. Examples of water-soluble resins include polyurethane resins, polyacrylic acid resins, polyvinyl alcohol, and polyvinylpyrrolidone. These may be used alone or in combination as needed. Among these, resin emulsions such as urethane resin emulsions and fluororesin emulsions are preferred in terms of improving weather resistance.

[0086] The aqueous coating material of the present invention can be produced by uniformly mixing the above-mentioned components (A), (B), and, if necessary, (C), various additives, etc., in a conventional manner.

[0087] [Film formation method] The aqueous coating material of the present invention is preferably applicable to surface finishing of the surfaces of buildings, civil engineering structures, etc. Examples of the surfaces to be coated in the present invention include exterior surfaces (e.g., exterior walls, roofs, etc.) of buildings, civil engineering structures, etc.

[0088] Examples of substrates that constitute the surface to be coated include concrete, mortar, porcelain tile, fiber-mixed cement board, cement calcium silicate board, slag cement perlite board, cement board, ALC board, siding board, gypsum board, plywood, extrusion molded board, steel plate, plastic plate, etc. When the surface to be coated is composed of multiple plate-shaped substrates, the joints between the plate-shaped substrates may be filled with a joint material such as a sealant or a dry joint material. The surfaces of these substrates may be subjected to some kind of surface treatment (e.g., treatment with putty, sealer, surfacer, filler, etc.), or may already have a coating film formed thereon (e.g., having an existing coating film).

[0089] The surface to be coated may have an existing coating film, which may be formed, for example, by one or more coating agents.

[0090] Various coating agents can be used, whether colored or uncolored, opaque or transparent, and examples include those containing one or more resins selected from vinyl acetate resin, alkyd resin, epoxy resin, acrylic resin, urethane resin, acrylic silicone resin, silicone resin, fluororesin, etc. The existing coating film is a coating of one or more layers, and may be, for example, an elastic type, a hard type, etc.

[0091] The aqueous coating material of the present invention can be applied directly to such a surface, or can be applied after treating the surface by applying a primer or a surface preparation material (e.g., sealer, primer, surfacer, filler, putty, etc.) to the surface.

[0092] The aqueous coating material of the present invention can also be applied after forming an elastic coating by applying an elastic coating material to the surface to be coated.

[0093] Examples of elastic coating materials include those architectural finishing coating materials specified in JIS A6909:2021 that exhibit flexibility or waterproofing, architectural coating membrane waterproofing materials specified in JIS A6021:2022, etc. Specific examples of elastic coating materials include flexible exterior silicate-based thin-applied finishing coating materials (flexible exterior thin coating material Si), flexible exterior synthetic resin emulsion-based thin-applied finishing coating materials (flexible exterior thin coating material E), waterproof exterior synthetic resin emulsion-based thin-applied finishing coating materials (waterproof exterior thin coating material E), flexible polymer cement-based multilayer finishing coating materials (flexible multilayer coating material CE), waterproof polymer cement-based multilayer finishing coating materials (waterproof multilayer coating material CE), waterproof synthetic resin emulsion-based multilayer finishing coating materials (waterproof multilayer coating material E), and waterproof reactive hardening synthetic resin Examples include emulsion-based multi-layer finishing coating materials (waterproof multi-layer coating materials RE), waterproof synthetic resin solution-based multi-layer finishing coating materials (waterproof multi-layer coating materials RS), flexible synthetic resin emulsion-based finishing coating materials for renovation (flexible renovation coating materials E), flexible reaction-hardening synthetic resin emulsion-based finishing coating materials for renovation (flexible renovation coating materials RE), flexible polymer cement-based finishing coating materials for renovation (flexible renovation coating materials CE), acrylic rubber-based waterproof coating materials for roofs, urethane rubber-based waterproof coating materials for roofs, acrylic rubber-based waterproof coating materials for exterior walls, and urethane rubber-based coating prevention materials for exterior walls.

[0094] The method for applying the elastic covering material is not particularly limited, and a method suitable for each material can be adopted. Examples of application tools that can be used include a spray, roller, trowel, and brush.

[0095] The amount of the elastic covering material applied is preferably 0.2 to 5 kg / m 2 , more preferably 0.3 to 4 kg / m 2 When applying, the elastic coating material can be diluted as needed.

[0096] Drying after application of the elastic coating material may be carried out at room temperature (5 to 40°C), or may be carried out with heat if necessary.

[0097] The elastic coating material can be applied directly to the surface to be coated, or it can be applied after the surface has been treated with a primer or a surface preparation material (e.g., sealer, primer, surfacer, filler, putty, etc.).

[0098] It is desirable that the elastic coating (coating of the elastic coating material) itself forms a coating with an elongation rate of 20% or more at -10° C. Such an elastic coating can exhibit advantageous effects, for example, in terms of its ability to follow the displacement of the coated surface and preventing the penetration of water, carbon dioxide, etc. into the coated surface. In the present invention, the elongation percentage at -10°C is a value measured according to the method specified in the "elongation test" of JIS A6909: 2021. For the elastic coating alone, a dry film thickness of 1 mm is subjected to the elongation test.

[0099] When applying the aqueous coating material of the present invention, various application tools can be used, such as a spray, roller, brush, etc. Among these, as the roller, for example, a fibrous roller with short, medium, or long pile (wool roller, etc.) can be used.

[0100] The amount of water to be added may be appropriately determined taking into consideration the type of coating equipment, the condition of the surface to be coated, the temperature during coating, etc., but is preferably 0 to 20% by mass of the total aqueous coating material.

[0101] The amount of the aqueous coating material of the present invention to be applied is preferably 0.05 to 1 kg / m 2 , more preferably 0.1 to 0.8 kg / m 2 , and more preferably 0.15 to 0.6 kg / m 2 By applying the aqueous coating material in such an amount, it is possible to form a coating film that is sufficiently excellent in appearance, weather resistance, etc.

[0102] The aqueous coating material of the present invention can be used as a room temperature curing aqueous coating material. Therefore, the application of the aqueous coating material of the present invention and drying after application can be carried out in an environment of room temperature (5 to 40°C). However, heating is also possible if necessary. The drying time is preferably about 0.5 to 4 hours at room temperature. The number of times of application can be one or two or more (preferably one to two times). When the number of times of application is two or more, it is desirable that the total amount of application is within the above range.

[0103] The aqueous coating material of the present invention can be preferably used as a topcoat material.

[0104] The present invention is a coating formation method in which two specific topcoat materials (a first topcoat material and a second topcoat material) are applied (painted) in order to a surface to be coated to form a topcoat material film.

[0105] <Top coat material> In the present invention, the first and second topcoat materials are applied to the surface to be coated in order to form a coating. Before applying the first topcoat material, as described above, one or more selected from the primer, base adjustment coating material, elastic coating material, etc. can also be applied.

[0106] In the present invention, the first topcoat material is used to form a coating with an elongation rate of 20% or more at -10 ° C., and the second topcoat material can be the aqueous coating material of the present invention described above. In the present invention, by applying such first and second topcoat materials in order to form a coating, it is possible to demonstrate excellent performance in terms of crack resistance, weather resistance, etc.

[0107] In the present invention, as the second topcoat material, in addition to the above-mentioned conditions, the elongation rate at -10°C is used to form a coating smaller than the elongation rate at -10°C of the first topcoat material.

[0108] The elongation rate of the second topcoat material at -10 ° C. is preferably 30% or less, more preferably 1 to 30%, even more preferably 5 to 28%, particularly preferably 10 to 26%. In the present invention, by using such a second topcoat material, it is possible to form a coating that exhibits excellent performance in blister resistance, contamination resistance, etc. The elongation rate of the second topcoat at -10°C is a value measured according to the method specified in the "elongation test" of JIS A6909:2021. The test specimen used for the elongation test was a waterproof multi-layer coating E main material with a dry film thickness of 1 mm (the single coating meets the elongation rate specification at -10°C specified in JIS A6909:2021), with a second topcoat coating applied to a dry film thickness of 80 μm.

[0109] The elongation rate of the second topcoat material at -10°C can be adjusted by the Tg of the (A) component in the second topcoat material, the content of the (B) component, etc. The Tg of the component (A) is 30°C or lower, preferably from -50°C to 25°C, more preferably from -40°C to 20°C, and even more preferably from -30°C to 15°C. The content of the component (B) is preferably 5 to 500 parts by mass, more preferably 10 to 300 parts by mass, and even more preferably 10 to 200 parts by mass per 100 parts by mass of the solid content of the component (A).

[0110] <1st top coat material> In the present invention, the first topcoat material is used to form a coating with an elongation rate of 20% or more (preferably 20 to 50%, more preferably 22 to 40%) at -10 ° C. And, the elongation rate of this first topcoat material at -10 ° C is greater than the elongation rate of the second topcoat material at -10 ° C. This makes it possible to form a coating that exhibits excellent performance in terms of crack resistance, weather resistance, etc. The elongation rate of the first topcoat material at -10°C is a value measured according to the method specified in the "elongation test" of JIS A6909:2021. The test specimen used for the elongation test was a waterproof multi-layer coating material E main material with a dry film thickness of 1 mm (the single coating meets the elongation rate specification at -10°C specified in JIS A6909:2021), with a first topcoat coating applied to a dry film thickness of 80 μm.

[0111] The first topcoat material can be a resin emulsion and a pigment. Such a first topcoat material can form a colored coating by hardening at room temperature. Among these, examples of resin emulsions include vinyl acetate resin emulsions, vinyl chloride resin emulsions, epoxy resin emulsions, alkyd resin emulsions, urethane resin emulsions, acrylic resin emulsions, acrylic silicone resin emulsions, fluororesin emulsions, and the like, as well as composites thereof, which can be used alone or in combination of two or more.

[0112] As the resin emulsion in the first topcoat material, an acrylic resin emulsion and an embodiment containing one or more selected from an acrylic silicone resin emulsion are suitable. The acrylic resin emulsion that can be used includes an alkyl (meth)acrylate ester as a resin component. The acrylic silicone resin emulsion can contain (meth)acrylic acid alkyl ester and alkoxysilane compound as resin components. The (meth)acrylic acid alkyl ester and alkoxysilane compound can be the same as the second top coat material (above-mentioned aqueous coating material of the present invention).

[0113] The resin emulsion in the first topcoat material is a monomer that constitutes the resin, and the Tg of the homopolymer is 0 ° C or less (preferably -15 ° C or less, more preferably -30 ° C or less), and can contain two or more (meth)acrylic acid alkyl esters (s) having an alkyl group with 4 or more carbon atoms. In the present invention, by providing the resin emulsion in the first topcoat material with such a specific configuration, it is possible to exhibit even better performance in terms of crack resistance, blister resistance, weather resistance, etc. The reasons for such performance are not limited to the following, but it is thought that the coexistence of two or more alkyl groups with different chemical structures increases film-forming properties based on the action of those alkyl groups, and that the strength of the film after film formation is imparted, and furthermore, the presence of alkyl groups similar to the second topcoat material contributes to increased adhesion. As the (s) component, the same materials as those detailed in the second topcoat material can be used.

[0114] In addition, the resin emulsion in the first topcoat material can also be configured such that the monomer constituting the resin contains a (meth)acrylic acid alkyl ester (s1) whose homopolymer Tg is 0°C or less (preferably -15°C or less, more preferably -30°C or less) and has a branched alkyl group with 5 or more carbon atoms. As the (s1) component, the same materials as those detailed in the second topcoat material can be used. The resin emulsion in the first topcoat material preferably contains at least one (s1) component as a monomer constituting the resin, and more preferably two or more, which allows it to exhibit even better performance in terms of crack resistance, blister resistance, weather resistance, etc. The reasons for this performance include, but are not limited to, the strength imparted to the film after film formation based on the action of the branched alkyl group, and the presence of an alkyl group similar to that of the second topcoat material, which is thought to contribute to increased adhesion.

[0115] In the resin emulsion of the first topcoat material, it is desirable that the branched alkyl group of the (s1) component contains a methyl group. Examples of (s1) components (hereinafter also referred to as "(s11) components") in which the branched alkyl group contains a methyl group include isoamyl acrylate, 2-octyl acrylate, isooctyl methacrylate, isooctyl acrylate, isononyl acrylate, isodecyl acrylate, isodecyl methacrylate, etc. The resin emulsion in the first topcoat material desirably contains at least one such (s11) component as a resin-constituting monomer, and more desirably contains two or more. By including such an (s11) component in the resin emulsion of the first topcoat material, it is possible to demonstrate even more excellent performance in terms of crack resistance, blister resistance, weather resistance, etc. The reasons for such performance include, but are not limited to, the effect of the branched alkyl group containing a methyl group, which contributes to the early imparting of strength to the coating after film formation.

[0116] The resin emulsion in the first topcoat material has a silica residual ratio in the resin solid content of preferably 0.5 to 40% by mass, more preferably 2 to 30% by mass, and even more preferably 4 to 25% by mass. This makes it more suitable in terms of crack resistance, weather resistance, etc.

[0117] The resin emulsion in the first topcoat material has a glass transition temperature (Tg) of preferably 30 ° C or less, more preferably -50 ° C to 30 ° C, and even more preferably -40 ° C to 25 ° C, which makes it more suitable in terms of room temperature curing and crack resistance. Specifically, the Tg of the acrylic resin emulsion is preferably from -40°C to 30°C, more preferably from -30°C to 25°C, and even more preferably from -20°C to 20°C. The Tg of the acrylic silicone resin emulsion is preferably from -50 to 20°C, more preferably from -40 to 10°C, and even more preferably from -30 to 5°C. In the resin emulsion in the first topcoat material, the type and ratio of the monomers used as the resin constituents can be set so as to satisfy the glass transition temperature.

[0118] The average particle size of the resin emulsion in the first topcoat material is preferably 300 nm or less, more preferably 20 to 250 nm, and even more preferably 50 to 200 nm. The average particle size referred to here is a value measured by dynamic light scattering.

[0119] In the first topcoat material, in addition to the resin emulsion, the pigment (B) which is an essential raw material of the aqueous coating material of the present invention described above can be contained. The pigment (B) is a component that contributes to at least one of color development, hiding power, strength, etc., and, as with the second topcoat material, for example, color pigment (B1), extender pigment (B2), etc. can be used.

[0120] The content of the (B) component is preferably 5 to 300 parts by mass, more preferably 10 to 200 parts by mass, and even more preferably 20 to 100 parts by mass, per 100 parts by mass of the solid content of the resin emulsion. By mixing the (B) component, the color tone of the first topcoat material can also be set to a color similar to that of the second topcoat material. As the coloring pigment (B1) and the extender pigment (B2), the same ones as those used in the second topcoat material (above-mentioned aqueous coating material of the present invention) can be used.

[0121] The average particle size of component (B1) is preferably 2 μm or less, more preferably 0.01 to 1 μm. The content of component (B1) is preferably 250 parts by mass or less, more preferably 5 to 200 parts by mass, and even more preferably 10 to 100 parts by mass, per 100 parts by mass of the solid content of the resin emulsion. A content of component (B1) within this range is more suitable in terms of the color development and hiding power of the coating.

[0122] The average particle size of component (B2) is preferably 0.1 to 100 μm, more preferably 0.3 to 50 μm. The content of component (B2) is preferably 200 parts by mass or less, more preferably 100 parts by mass or less, and even more preferably 50 parts by mass or less, per 100 parts by mass of the solid content of the resin emulsion. An embodiment that does not contain component (B2) is also suitable.

[0123] In the first topcoat material, a crosslinking agent (C) can be mixed with the resin emulsion. In this case, the resin emulsion can be a resin emulsion with a reactive functional group, and the (C) component can be a crosslinking agent that can react with the reactive functional group. When such a component is present, the crosslinking reaction between the resin emulsion and the crosslinking agent imparts strength to the coating during or after film formation, further improving physical properties such as crack resistance, blister resistance, and weather resistance.

[0124] As the component (C), the same materials as the second topcoat material (the aqueous coating material of the present invention described above) can be used.

[0125] The proportion of component (C) is preferably 0.05 to 50 parts by mass, more preferably 0.1 to 20 parts by mass, calculated as solid content, per 100 parts by mass of the resin solid content of the resin emulsion. Such a proportion can sufficiently improve crack resistance, blister resistance, weather resistance, etc.

[0126] In the first topcoat material, in addition to the above-mentioned components, various additives can also be mixed. Such additives include, for example, pigment dispersants, viscosity adjusters, leveling agents, coupling agents, wetting agents, film-forming aids, plasticizers, antifreeze agents, pH adjusters, preservatives, antifungal agents, anti-algae agents, antibacterial agents, antifoaming agents, adsorbents, deodorizers, ultraviolet absorbers, light stabilizers, hydrophilizing agents, antioxidants, catalysts, solvents, water, etc. These can be used alone or in combination as needed. Among these, the pigment dispersants can be the same as those used in the second topcoat material (the aqueous coating material of the present invention described above), and their content is preferably 0.01 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the solid content of the resin emulsion. In addition, the first topcoat material can also be mixed with an ether or ester solvent (D) (one or more selected from the group consisting of (D1) component, (D2) component, (D3) component, etc.), just like the second topcoat material.

[0127] In the first topcoat material, in addition to the above-mentioned components, water-soluble resins etc. can also be mixed. Examples of water-soluble resins include polyurethane resins, polyacrylic acid resins, polyvinyl alcohol, polyvinylpyrrolidone etc. These can be used as needed, one or more kinds.

[0128] The first topcoat material can be manufactured by uniformly mixing the above-mentioned components and, if necessary, various additives, etc., by conventional methods.

[0129] The elongation rate of the first topcoat material at -10°C can be adjusted by the Tg of the resin emulsion in the first topcoat material, the content of the (B) component, etc. Tg of the resin emulsion in the first topcoat material is preferably 30 ℃ or less, more preferably -50 ℃ to 30 ℃, further preferably -40 ℃ to 25 ℃. The content of the component (B) is preferably 5 to 300 parts by mass, more preferably 10 to 200 parts by mass, and even more preferably 20 to 100 parts by mass, per 100 parts by mass of the solid content of the resin emulsion.

[0130] <Film formation method> In the present invention, a topcoat film is formed by applying (painting) a topcoat material (first topcoat material and second topcoat material) to the surface to be coated. That is, the first topcoat material and the second topcoat material are applied in order to the surface to be coated to form a topcoat film. Before painting the first topcoat material, as described above, it is also possible to paint one or more selected from primers, surface adjustment coating materials, elastic coating materials, etc.

[0131] In the present invention, it is desirable to apply the first topcoat material, dry the coating, and then apply the second topcoat material. The first topcoat material and the second topcoat material can be the above-mentioned. In the present invention, by forming a laminated coating using these two specific topcoat materials, it is possible to demonstrate excellent performance in crack resistance, weather resistance, etc.

[0132] When applying each topcoat material, known painting tools can be used. For example, sprayers, rollers, brushes, etc. can be used as painting tools. When applying, each topcoat material can be diluted as needed.

[0133] The amount of water to be mixed may be appropriately determined taking into consideration the type of coating equipment, the condition of the surface to be coated, the temperature during coating, etc., but is preferably 0 to 20% by mass.

[0134] Both the first and second topcoat materials can be used as water-based topcoats that harden at room temperature. Therefore, the application of each topcoat material or drying after application can be carried out in an environment of room temperature (5 to 40 ° C). However, heating is also possible if necessary. The drying time is preferably about 0.5 to 4 hours at room temperature.

[0135] The amount of the first and second topcoat materials applied is preferably 0.05 to 0.4 kg / m 2 , more preferably 0.08 to 0.3 kg / m 2 is.

[0136] In addition, the dry film thickness of the first and second topcoat materials is preferably 20 to 300 μm, more preferably 30 to 200 μm, respectively. This makes it possible to form a coating that exhibits excellent performance in weather resistance, crack resistance, etc. while taking advantage of the texture of the base before the topcoat material is applied.

[0137] The film thickness ratio of the first topcoat material film to the second topcoat material film {(dry film thickness of the first topcoat material film): (dry film thickness of the second topcoat material film)} is preferably 80:20 to 20:80, more preferably 70:30 to 30:70, and even more preferably 65:35 to 35:65. By being in this mode, it is possible to stably obtain better performance in weather resistance, crack resistance, etc.

[0138] In the coating method of the present invention, for example, after applying one or more types selected from primers, base adjustment coating materials, elastic coating materials, etc. to the surface to be coated as needed, the first topcoat material and the second topcoat material can be applied in order. It is desirable to apply the second topcoat material after the coating of the first topcoat material has dried (preferably after drying for 1 hour or more, more preferably after drying for 2 hours or more).

[0139] [Topcoat set] In the present invention, the first and second topcoat materials described above can be used as a topcoat set consisting of these two types. That is, a topcoat set consisting of the first and second topcoat materials described above can be used to form a topcoat film on the surface to be coated. [Example]

[0140] The following examples will be given to clarify the features of the present invention, but the present invention is not limited to these examples.

[0141] (Manufacturing of water-based coating materials) The following raw materials were used to produce the aqueous coating materials in the examples.

[0142] Resin 1: Acrylic silicone resin emulsion (an emulsion polymer consisting primarily of cyclohexyl methacrylate-2-ethylhexyl acrylate-n-octyl acrylate-methacrylic acid-silane coupling agent-alkoxysilanes (mass ratio 38:14:12.5:1.5:1.5:32.5), glass transition temperature 3°C, residual silica ratio of resin solids 15% by mass, solids content 40% by mass) Resin 2: Acrylic silicone resin emulsion (an emulsion polymer consisting mainly of cyclohexyl methacrylate-2-octyl acrylate-n-octyl acrylate-methacrylic acid-silane coupling agent-alkoxysilanes (mass ratio 33:18.5:13:1.5:1.5:32.5), glass transition temperature 3°C, residual silica ratio in resin solids 15% by mass, solids 40% by mass) Resin 3: Acrylic silicone resin emulsion (emulsion polymer consisting mainly of methyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl acrylate, isoamyl acrylate, methacrylic acid, silane coupling agent, and alkoxysilanes (mass ratio 8:27:17:12.5:1.5:1.5:32.5), glass transition temperature 3°C, residual silica ratio in resin solids 15% by mass, solids 40% by mass)

[0143] Resin 4: Acrylic silicone resin emulsion (emulsion polymer consisting mainly of methyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl acrylate, isoamyl acrylate, diacetone acrylamide, methacrylic acid, silane coupling agent, and alkoxysilanes (mass ratio 8:25:16:14:1.5:1.5:1.5:32.5), glass transition temperature 3°C, residual silica ratio of resin solids 15% by mass, solid content 40% by mass) Resin 5: Acrylic silicone resin emulsion (emulsion polymer consisting mainly of methyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl acrylate, isoamyl acrylate, diacetone acrylamide, methacrylic acid, silane coupling agent, and alkoxysilanes (mass ratio 8:28:13:14:1.5:1.5:1.5:32.5), glass transition temperature 10°C, residual silica ratio in resin solids 15% by mass, solids 40% by mass) Resin 6: Acrylic silicone resin emulsion (emulsion polymer consisting mainly of methyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl acrylate, isoamyl acrylate, diacetone acrylamide, methacrylic acid, silane coupling agent, and alkoxysilanes (mass ratio 8:15.5:13:15.5:1.5:1.5:1.5:43.5), glass transition temperature -4°C, residual silica ratio of resin solids 20% by mass, solid content 40% by mass)

[0144] Resin 7: Acrylic silicone resin emulsion (an emulsion polymer consisting primarily of cyclohexyl methacrylate-2-ethylhexyl acrylate-2-octyl acrylate-diacetone acrylamide-methacrylic acid-silane coupling agent-alkoxysilanes (mass ratio 32.5:12:18.5:1.5:1.5:1.5:32.5), glass transition temperature 3°C, residual silica ratio of resin solids 15% by mass, solids content 40% by mass) Resin 8: Acrylic silicone resin emulsion (emulsion polymer consisting mainly of methyl methacrylate, cyclohexyl methacrylate, isoamyl acrylate, 2-octyl acrylate, diacetone acrylamide, methacrylic acid, silane coupling agent, and alkoxysilanes (mass ratio 5:22.5:17:18.5:1.5:1.5:1.5:32.5), glass transition temperature 3°C, residual silica ratio in resin solids 15% by mass, solids 40% by mass) Resin 9: Acrylic silicone resin emulsion (an emulsion polymer consisting primarily of cyclohexyl methacrylate, isobornyl acrylate, isoamyl acrylate, 2-octyl acrylate, diacetone acrylamide, methacrylic acid, silane coupling agent, and alkoxysilanes (mass ratio 23:5:18:17:1.5:1.5:1.5:32.5), glass transition temperature 3°C, residual silica ratio of resin solids 15% by mass, solids content 40% by mass)

[0145] Resin 10: Acrylic silicone resin emulsion (an emulsion polymer consisting primarily of cyclohexyl methacrylate, 2-ethylhexyl acrylate, n-octyl acrylate, diacetone acrylamide, methacrylic acid, silane coupling agent, and alkoxysilanes (mass ratio 36.5:13:13.5:1.5:1.5:1.5:32.5), glass transition temperature 3°C, residual silica content of resin solids 15% by mass, solid content 40% by mass) Resin 11: Acrylic silicone resin emulsion (an emulsion polymer consisting primarily of cyclohexyl methacrylate-2-octyl acrylate-n-octyl acrylate-diacetone acrylamide-methacrylic acid-silane coupling agent-alkoxysilanes (mass ratio 32:16:15:1.5:1.5:1.5:32.5), glass transition temperature 3°C, residual silica ratio in resin solids 15% by mass, solids 40% by mass)

[0146] Resin 12: Acrylic silicone resin emulsion (an emulsion polymer consisting primarily of cyclohexyl methacrylate-2-ethylhexyl acrylate-2-octyl acrylate-diacetone acrylamide-methacrylic acid-silane coupling agent-alkoxysilanes (mass ratio 39.5:16.5:18:1.5:1.5:1.5:21.5), glass transition temperature 3°C, residual silica ratio of resin solids 10% by mass, solids content 40% by mass) In addition, for resins 1 to 12, γ-methacryloxypropyltrimethoxysilane was used as the silane coupling agent, and methyltrimethoxysilane was used as the alkoxysilane.

[0147] Resin 13: Acrylic silicone resin emulsion (an emulsion polymer consisting primarily of cyclohexyl methacrylate-n-hexyl acrylate-2-octyl acrylate-diacetone acrylamide-methacrylic acid-silane coupling agent-alkoxysilanes (mass ratio 36.5:19:18.5:1.5:1.5:1.5:21.5), glass transition temperature 3°C, residual silica ratio of resin solids 10% by mass, solids content 40% by mass) In addition, in the resin 13, γ-methacryloxypropyltrimethoxysilane was used as the silane coupling agent, and methyltrimethoxysilane and phenyltrimethoxysilane (mass ratio 19.5:2) were used as the alkoxysilanes. Resin 14: Acrylic silicone resin emulsion (an emulsion polymer consisting primarily of cyclohexyl methacrylate, n-butyl acrylate, 2-octyl acrylate, diacetone acrylamide, methacrylic acid, silane coupling agent, alkoxysilanes, and cyclic siloxanes (mass ratio 36:17:22:1.5:1.5:1.5:17.5:3), glass transition temperature 3°C, residual silica ratio of resin solids 10% by mass, solid content 40% by mass) In addition, in the resin 14, γ-methacryloxypropyltrimethoxysilane was used as the silane coupling agent, and methyltrimethoxysilane and phenyltrimethoxysilane (mass ratio 14.5:3) were used as the alkoxysilanes.

[0148] Resin 15: Acrylic silicone resin emulsion (emulsion polymer consisting mainly of methyl methacrylate, cyclohexyl methacrylate, isoamyl acrylate, 2-octyl acrylate, diacetone acrylamide, methacrylic acid, silane coupling agent, and alkoxysilanes (mass ratio 5:24:29:21:1.5:1.5:1.5:16.5), glass transition temperature -6°C, residual silica ratio of resin solids 8% by mass, solid content 40% by mass) Resin 16: Acrylic resin emulsion (emulsion polymer consisting primarily of methyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl acrylate, n-butyl acrylate, diacetone acrylamide, and methacrylic acid (mass ratio 15:41.5:20:20.5:1.5:1.5), glass transition temperature 8°C, solid content 40% by mass)

[0149] Resin 17: Acrylic silicone resin emulsion (an emulsion polymer consisting mainly of cyclohexyl methacrylate, n-octyl acrylate, methacrylic acid, silane coupling agent, and alkoxysilanes (mass ratio 37:27.5:1.5:1.5:32.5), glass transition temperature 3°C, residual silica content of the resin solids of 15% by mass, solid content 40% by mass) Resin 18: Acrylic silicone resin emulsion (an emulsion polymer consisting primarily of cyclohexyl methacrylate, n-octyl acrylate, diacetone acrylamide, methacrylic acid, silane coupling agent, and alkoxysilanes (mass ratio 35.8:27.2:1.5:1.5:1.5:32.5), glass transition temperature 3°C, residual silica content of resin solids 15% by mass, solid content 40% by mass) In addition, for resins 15, 17, and 18, γ-methacryloxypropyltrimethoxysilane was used as the silane coupling agent, and methyltrimethoxysilane was used as the alkoxysilane.

[0150] Resin 19: Urethane resin emulsion (aqueous dispersion of polycarbonate-based polyurethane resin, solid content 30% by mass)

[0151] Color pigment 1: Titanium dioxide (average particle size 0.3 μm) Pigment dispersant 1: Polycarboxylic acid type dispersant (aqueous solution of polycarboxylic acid ammonium salt, solid content 30% by mass) Coloring liquid 1: Water dispersion of yellow iron oxide (average particle size 0.5 μm) [coloring pigment ratio 50% by mass, solids ratio of pigment dispersant {polycarboxylic acid type dispersant (styrene-maleic acid copolymer resin)} 2% by mass] Coloring liquid 2: Water dispersion of carbon black (average particle size 0.1 μm) [coloring pigment ratio 20% by mass, solids ratio of pigment dispersant {polymer dispersant with acid value and amine value, and phosphate type dispersant (phosphate ester compound)} 2% by mass] Solvent 1: Ether solvent (tripropylene glycol monobutyl ether, solubility in water 3g / 100gH2O, boiling point 274°C) Solvent 2: Ether solvent (dipropylene glycol monobutyl ether, solubility in water 5g / 100gH2O, boiling point 229°C) Solvent 3: Ether solvent (ethylene glycol monophenyl ether, solubility in water 2.6 g / 100 g H2O, boiling point 245°C) Solvent 4: Ether solvent (ethylene glycol monotertiary butyl ether, solubility in water infinite, boiling point 153°C) Solvent 5: Ether solvent (diethylene glycol monobutyl ether, solubility in water infinite, boiling point 230°C) Solvent 6: Ether solvent (diethylene glycol dibutyl ether, solubility in water 0.3 g / 100 g H2O, boiling point 255°C) Solvent 7: Ether solvent (ethylene glycol mono-2-ethylhexyl ether, solubility in water 0.2 g / 100 g H2O, boiling point 229°C) Solvent 8: Ether solvent (diethylene glycol monophenyl ether, solubility in water 3.4 g / 100 g H2O, boiling point 283 °C), Solvent 9: Ester solvent (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, solubility in water 0.09 g / 100 g H2O, boiling point 255°C) Thickener 1: Cellulose-based thickener Thickener 2: Polyurethane associative thickener Defoamer 1: Mineral oil-based defoamer Antifoaming agent 2: Silicone-based antifoaming agent Crosslinker 1: Adipic acid dihydrazide Crosslinker 2: Carbodiimide resin aqueous dispersion (solid content: 40% by mass) Crosslinker 3: γ-glycidoxypropyltrimethoxysilane

[0152] The full names of the abbreviations in the table are shown below. 2EHA: 2-ethylhexyl acrylate nOA: n-octyl acrylate 2OA: 2-octyl acrylate IAA: Isoamyl acrylate nHA: n-hexyl acrylate nBA: n-butyl acrylate

[0153] <Water-based coating material 1> A color pigment dispersion was prepared by mixing and stirring 27 parts by mass of water, 0.4 parts by mass of thickener 1, 0.1 parts by mass of antifoaming agent 1, 2.5 parts by mass of pigment dispersant 1, and 70 parts by mass of color pigment 1. Next, 100 parts by mass of this color pigment dispersion liquid was mixed and stirred with 250 parts by mass of resin 1 (100 parts by mass in terms of solid content), 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, and 0.2 parts by mass of antifoaming agent 2 to produce aqueous coating material 1.

[0154] <Aqueous coating material 2> Aqueous coating material 2 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 2, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, and 0.2 parts by mass of antifoaming agent 2.

[0155] <Water-based coating material 3> Aqueous coating material 3 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 3, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, and 0.2 parts by mass of antifoaming agent 2.

[0156] <Aqueous coating material 4> Aqueous coating material 4 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 4, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0157] <Water-based coating material 5> Aqueous coating material 5 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 5, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0158] <Aqueous coating material 6> Aqueous coating material 6 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 6, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0159] <Water-based coating material 7> Aqueous coating material 7 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 7, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0160] <Aqueous coating material 8> Aqueous coating material 8 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 8, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0161] <Aqueous coating material 9> Aqueous coating material 9 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 9, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0162] <Aqueous coating material 10> Aqueous coating material 10 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 8, 18 parts by mass of solvent 2, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0163] <Aqueous coating material 11> Aqueous coating material 11 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 8, 12 parts by mass of solvent 2, 6 parts by mass of solvent 3, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0164] <Aqueous coating material 12> Aqueous coating material 12 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 8, 12 parts by mass of solvent 2, 6 parts by mass of solvent 4, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0165] <Aqueous coating material 13> Aqueous coating material 13 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 8, 12 parts by mass of solvent 2, 6 parts by mass of solvent 5, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0166] <Aqueous coating material 14> Aqueous coating material 14 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 8, 12 parts by mass of solvent 2, 6 parts by mass of solvent 6, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0167] <Aqueous coating material 15> Aqueous coating material 15 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 8, 12 parts by mass of solvent 2, 6 parts by mass of solvent 7, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0168] <Aqueous coating material 16> Aqueous coating material 16 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 9, 12 parts by mass of solvent 2, 6 parts by mass of solvent 3, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0169] <Aqueous coating material 17> Aqueous coating material 17 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 10, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0170] <Aqueous coating material 18> Aqueous coating material 18 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 11, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0171] <Aqueous coating material 19> Aqueous coating material 19 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 3, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 3 parts by mass of crosslinking agent 2.

[0172] <Aqueous coating material 20> Aqueous coating material 20 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 12, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0173] <Aqueous coating material 21> Aqueous coating material 21 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 13, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0174] <Aqueous coating material 22> An aqueous coating material 22 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 14, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0175] <Aqueous coating material 23> Aqueous coating material 23 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 9, 2 parts by mass of solvent 2, 2 parts by mass of solvent 8, 11 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0176] <Aqueous coating material 24> Aqueous coating material 24 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass of resin 9 (equivalent to 100 parts by mass of solids), 2 parts by mass of solvent 2, 2 parts by mass of solvent 8, 11 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, 1 part by mass of crosslinking agent 1, and 10 parts by mass of coloring liquid 1.

[0177] <Aqueous coating material 25> Aqueous coating material 25 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass of resin 9 (equivalent to 100 parts by mass of solids), 2 parts by mass of solvent 2, 2 parts by mass of solvent 8, 11 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, 1 part by mass of crosslinking agent 1, and 10 parts by mass of coloring liquid 2.

[0178] <Aqueous coating material 26> Aqueous coating material 26 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (100 parts by mass in terms of solid content) of resin 9, 2 parts by mass of solvent 2, 2 parts by mass of solvent 8, 11 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 3.

[0179] <Aqueous coating material 27> Aqueous coating material 27 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 220 parts by mass of resin 10 (88 parts by mass in terms of solid content), 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, 1 part by mass of crosslinker 1, and 40 parts by mass of resin 19 (12 parts by mass in terms of solid content).

[0180] <Aqueous coating material 28> Aqueous coating material 28 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1 with 220 parts by mass of resin 9 (88 parts by mass in terms of solid content), 2 parts by mass of solvent 2, 2 parts by mass of solvent 8, 11 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, 1 part by mass of crosslinking agent 1, and 40 parts by mass of resin 19 (12 parts by mass in terms of solid content).

[0181] <Aqueous coating material 29> Aqueous coating material 29 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 17, 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, and 0.2 parts by mass of antifoaming agent 2.

[0182] <Water-based coating material 30> Aqueous coating material 30 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass (equivalent to 100 parts by mass of solid content) of resin 17, 2 parts by mass of thickener 2, and 0.2 parts by mass of antifoaming agent 2.

[0183] <Aqueous coating material 31> Aqueous coating material 31 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as in Example 1, 250 parts by mass of resin 18 (equivalent to 100 parts by mass of solid content), 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1.

[0184] <Aqueous coating material 32> Aqueous coating material 32 was produced by mixing and stirring 250 parts by mass of resin 17 (100 parts by mass in terms of solid content), 18 parts by mass of solvent 1, 2 parts by mass of thickener 2, and 0.2 parts by mass of antifoaming agent 2.

[0185] (Test Method) Each water-based coating material was tested in the following manner.

[0186] [Test 1] The test substrate was a slate board with a roughened pattern (height difference of approximately 1.5 mm) formed using a thick synthetic resin emulsion finish coating material. Each water-based coating material was applied to this test substrate at an amount of 0.3 kg / m. 2 The coating was spray painted on at 100°C, and the surface was placed horizontally in an incubator at 5°C and allowed to dry for 168 hours, after which the appearance of the coating was observed. The evaluation criteria were "A" for no cracks, "B" for slight cracks, and "C" for obvious cracks. A "C" is a level that is problematic for practical use.

[0187] [Test 2] Each water-based coating material was applied to one side of a glass plate using a film applicator with a gap of 150 μm, and the coated surface was placed horizontally and allowed to dry for 48 hours under standard conditions (temperature 23°C, relative humidity 50%), after which the 20-degree specular gloss (measurement angle 20 degrees) was measured. The evaluation criteria were as follows: a 20-degree specular gloss of 46 or more was rated "AA," 43 to 46 was rated "A," 40 to 43 was rated "B," and less than 40 was rated "C." Note that a level that is problematic for practical use was rated "C."

[0188] [Test 3] After performing Test 1 above, the test panels were dried under standard conditions (temperature 23°C, relative humidity 50%) for 14 days, and then exposed to an accelerated weathering tester (xenon weather meter) for 1000 hours, after which the appearance of the coating was observed. The evaluation criteria were "A" for no cracks, "B" for slight cracks, and "C" for obvious cracks. Note that "C" is a level that is problematic for practical use.

[0189] [Test 4] The test substrate was a slate board coated with a flexible synthetic resin emulsion-based finishing coating (0.5 mm thick). Each water-based coating material was applied to the test substrate at a rate of 0.3 kg / m. 2 Test specimens were prepared by spray painting the coating onto the surface of the test piece with a temperature of 5°C, placing the painted surface horizontally in an incubator at 5°C, and drying for 24 hours. The test specimens were then immersed in water at 23°C for 24 hours, and the appearance of the coating film was observed. The evaluation criteria were as follows: no blistering was given an "AA", very slight blistering was given an "A", slight blistering was given an "B", and obvious blistering was given a "C". Note that a "C" level is problematic for practical use.

[0190] (Test results) The test results are shown in Table 1. In Test 1, Examples 1 to 28 (particularly Examples 3 to 28) gave good results, and were excellent in crack resistance. In Test 2, Examples 1 to 28 (particularly Examples 11 to 16, 23 to 26, and 28) gave good results, and were excellent in gloss. In Test 3, Examples 3 to 28 (particularly Examples 4 to 16 and 18 to 28) also gave good results, and were excellent in crack resistance and weather resistance. In Test 4, Examples 1 to 28 (particularly Examples 2 to 16 and 18 to 28) gave good results, and were excellent in coating film strength developed early and in blister resistance. Comparative Examples 1 to 3 showed insufficient results in Test 1, so Test 3 was not performed for Comparative Examples 1 to 3. Comparative Example 4 did not contain pigments or the like, which is outside the scope of the present invention, so Tests 2 and 3 were not performed.

[0191] [Table 1]

[0192] [Table 2]

[0193] [Table 3]

[0194] <Top coating material 1> A color pigment dispersion was prepared by mixing and stirring 27 parts by mass of water, 0.4 parts by mass of thickener 1, 0.1 parts by mass of antifoaming agent 1, 2.5 parts by mass of pigment dispersant 1, and 70 parts by mass of color pigment 1. Next, 100 parts by mass of this color pigment dispersion liquid was mixed and stirred with 250 parts by mass of resin 1 (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, and 0.2 parts by mass of antifoaming agent 2 to produce topcoat material 1. The elongation rate of this topcoat material 1 at -10°C was 17%.

[0195] <Top coating material 2> Topcoat material 2 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, and 0.2 parts by mass of antifoaming agent 2. The elongation rate of this topcoat material 2 at -10°C was 18%.

[0196] <Top coating material 3> Topcoat material 3 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, and 0.2 parts by mass of antifoaming agent 2. The elongation rate of this topcoat material 3 at -10°C was 18%.

[0197] <Top coating material 4> Topcoat material 4 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 4 at -10°C was 18%.

[0198] <Top coating material 5> Topcoat material 5 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 5 at -10°C was 18%.

[0199] <Top coating material 6> Topcoat material 6 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids content), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 3 parts by mass of crosslinking agent 2. The elongation rate of this topcoat material 6 at -10°C was 20%.

[0200] <Top coating material 7> Topcoat material 7 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 7 at -10°C was 20%.

[0201] <Top coating material 8> Topcoat material 8 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids content), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 8 at -10°C was 14%.

[0202] <Top coating material 9> Topcoat material 9 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids content), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 9 at -10°C was 26%.

[0203] <Top coat material 10> Topcoat material 10 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 10 at -10°C was 23%.

[0204] <Top coating material 11> Topcoat material 11 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 11 at -10°C was 20%.

[0205] <Top coating material 12> Topcoat material 12 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 12 at -10°C was 18%.

[0206] <Top coating material 13> Topcoat material 13 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 2, 6 parts by mass of solvent 8, 6 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 13 at -10°C was 21%.

[0207] <Top coating material 14> Topcoat material 14 was produced by mixing and stirring 100 parts by mass of a color pigment dispersion similar to that used in topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 12 parts by mass of solvent 2, 6 parts by mass of solvent 8, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 14 at -10°C was 20%.

[0208] <Top coating material 15> Topcoat material 15 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 15 at -10°C was 18%.

[0209] <Top coating material 16> Topcoat material 16 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 16 at -10°C was 19%.

[0210] <Top coating material 17> Topcoat material 17 was produced by mixing and stirring 100 parts by mass of a color pigment dispersion similar to that used in coating material 1 with 250 parts by mass (100 parts by mass of solids content), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, and 0.2 parts by mass of antifoaming agent 2. The elongation rate of this topcoat material 17 at -10°C was 18%.

[0211] <Top coating material 18> Topcoat material 18 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 18 at -10°C was 18%.

[0212] <Top coating material 19> Topcoat material 19 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 19 at -10°C was 32%.

[0213] <Top coating material 20> Topcoat material 20 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 125 parts by mass of resin 8 (50 parts by mass in solids), 125 parts by mass of resin 16 (50 parts by mass in solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 20 at -10°C was 30%.

[0214] <Top coating material 21> Topcoat material 21 was produced by mixing and stirring 100 parts by mass of the same color pigment dispersion as topcoat material 1 with 250 parts by mass (100 parts by mass of solids), 6 parts by mass of solvent 8, 12 parts by mass of solvent 9, 2 parts by mass of thickener 2, 0.2 parts by mass of antifoaming agent 2, and 1 part by mass of crosslinking agent 1. The elongation rate of this topcoat material 21 at -10°C was 38%.

[0215] The elongation rate of each topcoat material at -10°C was measured according to the method specified in the "elongation test" of JIS A6909:2021. The test specimen used in the elongation test was a waterproof multi-layer coating material E (main material: acrylic resin emulsion (Tg -28°C), titanium dioxide (average particle size 0.3μm), heavy calcium carbonate (average particle size 12μm), etc.) corresponding to JIS A6909:2021, with a dry film thickness of 1mm and a topcoat coating layer applied to a dry film thickness of 80μm.

[0216] (Test Method) Each coating material was tested in the following manner.

[0217] [Test 5] The test substrate was a slate board with an uneven pattern (height difference of approximately 1.5 mm) formed by the waterproof multi-layer coating material E (main material: acrylic resin emulsion (Tg -28°C), titanium oxide (average particle size 0.3 μm), heavy calcium carbonate (average particle size 12 μm), etc., which conforms to JIS A6909:2021. The elongation rate of the single coating at -10°C is 38%). The first topcoat material was applied to this test substrate at a rate of 0.15 kg / m. 2 Spray paint at 1000 W, let it dry for 2 hours, then apply the second top coat at a rate of 0.15 kg / m 2 The test specimens were then spray-painted with 168 hours of drying and curing. The painting, drying, and curing were all carried out under standard conditions (temperature 23°C, relative humidity 50%).

[0218] The test specimens obtained using the above method were subjected to a total of 10 cycles of repeated heating and cooling, with one 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 was checked and the state of defects (blistering, peeling, cracks, etc.) was evaluated. The evaluation was conducted on a four-point scale (excellent: A>B>C>D: poor), with "A" indicating no defects and "D" indicating clear defects. Note that "C" and "D" are levels that are problematic for practical use.

[0219] [Test 6] Test specimens obtained in the same manner as in Test 5 above were exposed for 1000 hours in an accelerated weathering tester (xenon weather meter), after which the coating appearance was observed. Evaluation was conducted on a four-point scale (excellent: A>B>C>D: poor), with "A" indicating no defects and "D" indicating clear defects. "C" and "D" are considered to be practically problematic.

[0220] (Test results) The test results are shown in Table 6. Examples 29 to 47 showed good results in Tests 5 and 6, and were excellent in crack resistance, weather resistance, and the like.

[0221] [Table 4]

[0222] [Table 5] Note) All resins except "Resin 16" included in the "Resin Components" in Table 5 above contain acrylic silicone resin, and "Resin 16" does not contain silicone components.

[0223] [Table 6]

Claims

1. An aqueous coating material having room temperature curing properties, comprising an acrylic silicone resin emulsion (A) and a pigment (B), the silica residual ratio in the resin solid content of the acrylic silicone resin emulsion (A) is 1 to 40 mass %, The glass transition temperature of the acrylic silicone resin emulsion (A) is 30°C or less, the acrylic silicone resin emulsion (A) contains, as a monomer constituting the emulsion, two or more kinds of (meth)acrylic acid alkyl esters (s) each having an alkyl group having 4 or more carbon atoms, and the glass transition temperature of a homopolymer of the (meth)acrylic acid alkyl esters (s) each having an alkyl group having 4 or more carbon atoms is 0°C or lower; the (meth)acrylic acid alkyl ester (s) having an alkyl group having 4 or more carbon atoms includes a (meth)acrylic acid alkyl ester (s1) having a branched alkyl group having 5 or more carbon atoms, The aqueous coating material is characterized in that the branched alkyl group contains a methyl group.

2. Contains a crosslinking agent (C), the acrylic silicone resin emulsion (A) has a reactive functional group, 2. The aqueous coating material according to claim 1, wherein the crosslinking agent (C) has a functional group capable of reacting with the reactive functional group.

3. an ether or ester solvent (D), The component (D) has a solubility in water of 0.5 to 50 g / 100 gH ２ 2. The aqueous coating material according to claim 1, characterized in that it contains an ether or ester solvent (D1) of O.

4. A coating method for forming a coating film by applying a first topcoat material and a second topcoat material to a surface to be coated in sequence, The first topcoat material forms a coating having an elongation rate of 20% or more at -10 ° C., The second topcoat material is an aqueous coating material having room temperature curing properties containing an acrylic silicone resin emulsion (A) and a pigment (B), the silica residual ratio in the resin solid content of the acrylic silicone resin emulsion (A) is 1 to 40 mass %, The glass transition temperature of the acrylic silicone resin emulsion (A) is 30°C or less, the aqueous coating material contains, as a monomer constituting the acrylic silicone resin emulsion (A), two or more kinds of (meth)acrylic acid alkyl esters (s) having an alkyl group having 4 or more carbon atoms, and the glass transition temperature of a homopolymer of the (meth)acrylic acid alkyl esters (s) having an alkyl group having 4 or more carbon atoms is 0°C or lower; The second topcoat material is characterized in that the elongation rate at -10 ° C. is smaller than the elongation rate at -10 ° C. of the first topcoat material, forming a coating film.

5. 5. The coating forming method according to claim 4, wherein the (meth)acrylic acid alkyl ester (s) having an alkyl group having 4 or more carbon atoms includes a (meth)acrylic acid alkyl ester (s1) having a branched alkyl group having 5 or more carbon atoms.

6. 6. The method for forming a coating according to claim 5, wherein the branched alkyl group contains a methyl group.

7. The second topcoat material contains a crosslinking agent (C), the acrylic silicone resin emulsion (A) has a reactive functional group, 5. The method for forming a coating film according to claim 4, wherein the crosslinking agent (C) has a functional group capable of reacting with the reactive functional group.

8. The first topcoat material includes a resin emulsion and a pigment, 5. The coating forming method according to claim 4, wherein the resin emulsion contains, as a monomer, two or more kinds of (meth)acrylic acid alkyl esters (s) having an alkyl group with 4 or more carbon atoms, and the glass transition temperature of a homopolymer of the (meth)acrylic acid alkyl esters (s) having an alkyl group with 4 or more carbon atoms is 0°C or lower.

9. 9. The coating forming method according to claim 8, wherein the (meth)acrylic acid alkyl ester (s) having an alkyl group having 4 or more carbon atoms includes a (meth)acrylic acid alkyl ester (s1) having a branched alkyl group having 5 or more carbon atoms.

10. 10. The method for forming a coating according to claim 9, wherein the branched alkyl group includes a methyl group.

11. A topcoat material set comprising the first topcoat material and the second topcoat material used in the coating formation method according to claim 4.

Images