Resin composition for paint, paint and coating film

Abstract

To provide a resin composition from which a coated film suppressing cracking under outdoor environment can be obtained, and that has a long pot life and is excellent in curability.SOLUTION: A resin composition for coating contains a main agent (A) containing an amino group-containing acrylic resin (a1) and a siloxane oligomer (a2), and a curing agent (B) containing a polyepoxide (b1) and a curing catalyst (b2), wherein (a1) has an amine value of 8 mgKOH / g or more and 90 mgKOH / g or less, (b1) has an epoxy equivalent of 100 g / eq or more and 1,500 g / eq or less, in (a1), a reactive group capable of reacting with a silanol group does not exist or the number of the reactive groups is less than 11% of the number of the amino groups in (a1), and in (b1), the reactive group does not exist, or the number of the reactive groups is less than 10% of the number of the epoxy groups in (b1), and the curing catalyst (b2) contains an organometallic compound.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition for paint, a paint, and a coating film. [Background technology]

[0002] Weather resistance is required for paints for outdoor buildings. Therefore, hybrid coating films in which an organic component and an inorganic component such as polysiloxane are chemically bonded have been proposed. Hybrid coating films are formed using the paints described in Patent Documents 1 to 4, for example. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-145268 [Patent Document 2] Japanese Patent Application Publication No. 2018-145371 [Patent Document 3] International Publication No. 2019 / 107124 [Patent Document 4] Japanese Patent Publication No. 2020-164583 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Documents 1 and 2 disclose resin compositions in which a vinyl polymer (a1) and a polysiloxane (a2) are chemically bonded. Patent Document 3 discloses a coating composition containing (B) a compound having one or more functional groups capable of undergoing a Michael addition reaction with an acryloyloxy group and an alkoxy group, (C) a tri- or higher-functional aliphatic urethane acrylate oligomer, and (A) a silicone resin having reactive groups reactive with (B) and (C). Patent Document 4 discloses a coating composition containing a polyorganosiloxane and an acrylic resin having a hydroxyl group or a reactive silicon group. These compositions have a short pot life. Although these compositions all form hybrid coating films, the resulting hybrid coating films are prone to cracking in outdoor environments.

[0005] The present invention has been made in view of the above, and an object of the present invention is to provide a resin composition which can give a coating film that suppresses the occurrence of cracks in outdoor environments, has a long pot life, and is excellent in curability. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention provides the following aspects. [1] Contains a base agent (A) and a curing agent (B), The main component (A) contains an amino group-containing acrylic resin (a1) and a siloxane oligomer (a2), the curing agent (B) contains a polyepoxide (b1) and a curing catalyst (b2), the amino group-containing acrylic resin (a1) has an amine value of 10 mgKOH / g or more and 88 mgKOH / g or less, the polyepoxide (b1) has an epoxy equivalent of 100 g / eq or more and 1,500 g / eq or less, the amino group-containing acrylic resin (a1) does not have any reactive groups capable of reacting with silanol groups, or the number of such reactive groups is less than 11% of the number of amino groups in the amino group-containing acrylic resin (a1); In the polyepoxide (b1), there is no reactive group capable of reacting with a silanol group, or the number of the reactive groups is less than 10% of the number of epoxy groups in the polyepoxide (b1). The siloxane oligomer (a2) is represented by the following general formula (x): [ka] (In the formula, R 3 represents independently in each structural unit a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a single bond, R 4 represents, independently in each structural unit, an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 15 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a divalent oxygen atom; m is an integer from 0 to 200. and a structural unit X represented by the following general formula (y): [ka] (In the formula, R 5 and R 6 each independently in each repeating unit represents an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms; n is an integer from 0 to 200. and a structural unit Y represented by has, as a terminal group, at least one selected from the group consisting of a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms; m+n is 2 to 200; the curing catalyst (b2) comprises an organometallic compound, a resin composition for paint, wherein the mass ratio of the organometallic compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass % or more and 30 mass % or less; A coating film formed from the coating resin composition is subjected to an outdoor exposure test in accordance with JIS K5600-7-6 in Miyakojima, facing the equatorial plane at an angle of 20° to the horizontal, for one and a half years, after which the gloss retention rate in accordance with JIS K5659 7.21 is 80% or more. [2] The resin composition for coating according to [1] above, wherein the organometallic compound comprises at least one selected from the group consisting of alkoxide compounds, chelate compounds and acylate compounds of metals having a coordination number of 2 to 8. [3] The resin composition for paint according to [2] above, wherein the metal having a coordination number of 2 to 8 includes at least one selected from the group consisting of titanium, tin, zinc, aluminum, nickel, iron and zirconium. [4] The resin composition for coating according to the above [1] or [2], wherein the curing catalyst (b2) comprises at least one selected from the group consisting of organotitanium compounds, organozirconium compounds and organoaluminum compounds. [5] The organotitanium compound is The following general formula (C t1 ): Ti(OR t1 )4(C t1 ) (In the formula, OR t1 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearoxy group, an isostearic acid group, or an acetylacetonate group), The following general formula (C t2 ): Ti(OR t2 ) mt (L t1 ) 4-mt (C t2 ) (In the formula, OR t2 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearoxy group, an isostearic acid group, or an acetylacetonate group, L t1each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group, mt is an integer from 1 to 3, and The following general formula (C t3 ): Ti(L t2 )4(C t3 ) (In the formula, L t2 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group. The resin composition for paint according to [4] above, which contains at least one compound selected from the group consisting of compounds represented by the following formula: [6] The organic zirconium compound is The following general formula (C z1 ): Zr(OR z1 )4(Cz1) (In the formula, OR z1 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearic acid group, or an octylic acid group), The following general formula (C z2 ): Zr(OR z2 ) mz (L z1 ) 4-mz (C z2 ) (In the formula, OR z2 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearic acid group, or an octylic acid group, L z1each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group, mz is an integer from 1 to 3, and The following general formula (C z3 ): Zr(L z2 )4(C z3 ) (In the formula, L z2 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group. The resin composition for paint according to [4] above, which contains at least one compound selected from the group consisting of compounds represented by the following formula: [7] The organoaluminum compound is The following general formula (C a1 ): Al(OR a1 )3 (In the formula, OR a1 each independently represents an alkoxy group having 1 to 4 carbon atoms), The following general formula (C a2 ): Al(OR a2 ) ma (L a1 ) 3-ma (C a2 ) (In the formula, OR a2 each independently represents an alkoxy group having 1 to 4 carbon atoms, L a1 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, a proponylacetonato group, or a stearylacetonato group, ma is an integer from 1 to 3, and The following general formula (C a3 ): Al(L a2 )3(C a3 ) (In the formula, L a2 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, a proponylacetonato group, or a stearylacetonato group. The resin composition for paint according to [4] above, which contains at least one compound selected from the group consisting of compounds represented by the following formula: [8] The resin composition for coating according to the above [1] or [2], wherein the curing catalyst (b2) comprises at least one selected from the group consisting of organic titanium compounds and organic zirconium compounds, and an organic aluminum compound. [9] the curing catalyst (b2) comprises an organotitanium compound and an organoaluminum compound, a mass ratio of the organotitanium compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass% or more and 12 mass% or less; The resin composition for paint according to the above [1] or [2], wherein the mass ratio of the organoaluminum compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass % or more and 20 mass % or less.

[10] the curing catalyst (b2) comprises an organozirconium compound and an organoaluminum compound, a mass ratio of the organic zirconium compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass% or more and 12 mass% or less; The resin composition for paint according to the above [1] or [2], wherein the mass ratio of the organoaluminum compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass % or more and 20 mass % or less.

[11] The resin composition for coating according to the above [1] or [2], wherein the reactive group is at least one selected from the group consisting of a hydroxyl group, an alkoxy group, an alkoxysilyl group and a silanol group.

[12] A paint comprising the resin composition for paint according to [1] or [2] above.

[13] Furthermore, the paint described above in

[12] contains a third-class organic solvent as defined in the Industrial Safety and Health Act.

[14] It is formed from the resin composition for paint of [1] above, a first polymer portion formed by a reaction product of the amino group-containing acrylic resin (a1) and the polyepoxide (b1); a second polymer portion formed by a polymer of the siloxane oligomer (a2) polymerized in the presence of the curing catalyst (b2) containing the organometallic compound, and independent of the first polymer portion; at least a portion of the first polymer portion and at least a portion of the second polymer portion are entangled; The second polymer portion comprises a metal from the organometallic compound. [Effects of the Invention]

[0007] According to the present invention, a resin composition that can produce a coating film that suppresses the occurrence of cracks in outdoor environments and that has a long pot life and excellent curability, and a paint containing the same are provided. According to the present invention, a coating film that suppresses the occurrence of cracks in outdoor environments is also provided. DETAILED DESCRIPTION OF THE INVENTION

[0008] Coatings formed from polysiloxanes are said to have excellent weather resistance. However, when exposed to moisture and heat for a long period of time, the polysiloxanes condense, causing the coating to shrink unevenly. Hybrid coatings aim to mitigate the shrinkage of coatings caused by polysiloxane condensation by chemically bonding (typically covalently) an organic component to the polysiloxane to impart flexibility to the coating. However, it has been found that chemically bonding a polysiloxane to an organic component results in insufficient weather resistance of the polysiloxane to factors other than moisture, and insufficient shrinkage mitigation due to the flexibility of the organic component. Hereinafter, weather resistance refers to resistance to ultraviolet light, heat, and moisture.

[0009] In the present disclosure, the organic components, the amino group-containing acrylic resin (a1) and polyepoxide (b1), do not react with the inorganic component, the siloxane oligomer (a2), or the reaction is suppressed. Therefore, in the resulting coating film, the first polymer portion formed by the reaction product of the amino group-containing acrylic resin (a1) and polyepoxide (b1) and the second polymer portion formed by the polymer of the siloxane oligomer (a2) (or the polymer of the siloxane oligomer (a2) containing the curing catalyst (b2); the same applies below) are substantially independent of each other. This allows the coating film to exhibit both the properties of the organic components (e.g., flexibility) and the properties of the inorganic components (e.g., resistance to ultraviolet light and heat).

[0010] When the functions of both the first polymer (organic component) and the second polymer (inorganic component) are fully exhibited, the first polymer can exist in the coating film without shrinking in response to the shrinkage caused by condensation of the second polymer. This reduces the shrinkage of the entire coating film, thereby suppressing, for example, the occurrence of microcracks. Furthermore, the resistance of the second polymer to ultraviolet light and heat suppresses, for example, the occurrence of chalking.

[0011] Furthermore, a coating film formed from the resin composition according to the present disclosure has a gloss retention of 80% or more as measured in accordance with JIS K5659 7.21 after one and a half years of outdoor exposure testing (hereinafter sometimes simply referred to as "outdoor exposure testing") conducted in Miyakojima, facing the equatorial plane at an angle of 20° relative to the horizontal, in accordance with JIS K5600-7-6. The gloss retention may be 83% or more, or 85% or more.

[0012] The outdoor exposure test may be carried out, for example, by an external testing organization (typically, the Miyakojima Exposure Test Site (Miyakojima City, Okinawa Prefecture) of the Japan Weathering Test Center (JWTC), a general incorporated foundation).

[0013] Gloss retention indicates changes in the surface condition of the coating film (e.g., changes in surface irregularities and surface roughness). In outdoor exposure tests, the coating film is exposed to ultraviolet rays, heat, and moisture (e.g., rain, snow, frost), etc. A gloss retention of 80% or more after this outdoor exposure test means that there is very little change in the surface condition even when exposed to ultraviolet rays, heat, and water, etc. Typically, ultraviolet rays, heat, and moisture deteriorate the organic component (first polymer) and promote shrinkage of the inorganic component (second polymer).

[0014] In outdoor exposure tests, the surface condition changes due to, for example, deterioration of the first polymer and / or shrinkage of the second polymer. Small changes in the surface condition (i.e., gloss retention of the coating film after outdoor exposure tests of 80% or more) indicate, in other words, that both the first polymer and the second polymer are sufficiently cured and that the functions of both the first polymer and the second polymer are fully exerted. When the first polymer and the second polymer are substantially independent of each other, the gloss retention of the coating film after outdoor exposure tests is likely to be 80% or more.

[0015] Degradation of the first polymer and shrinkage of the second polymer manifests as microcracking and / or chalking, reduced adhesion, and discoloration.

[0016] The organic component is a component containing a carbon-carbon bond in its main chain, and herein may refer to the first polymer as well as the material of the first polymer (i.e., the amino group-containing acrylic resin (a1) and the polyepoxide (b1)). The inorganic component is a component containing a bond other than a carbon-carbon bond in its main chain (herein, Si—O), and herein may refer to the second polymer as well as the material of the second polymer (i.e., the siloxane oligomer (a2)).

[0017] The phrase "the first and second polymer portions are substantially independent of each other" allows for bonding between the amino group-containing acrylic resin and / or polyepoxide and the siloxane oligomer, which can occur within the range where the ratio R1 is 0% or less than 11% and the ratio R2 is 0% or less than 10%. The amino group-containing acrylic resin and / or polyepoxide and the siloxane oligomer may or may not be bonded within the above-mentioned allowable range. The bond between the two may or may not be via another compound.

[0018] In addition, the resin composition according to the present disclosure contains a specific amount of an organometallic compound as a curing catalyst (b2). This improves curability. Furthermore, both the crosslinking reaction of the organic component and the condensation reaction of the inorganic component can proceed simultaneously over a wide temperature range (e.g., 0°C to 40°C) and a wide relative humidity range (e.g., 40%RH to 85%RH). Therefore, in the resulting coating film, the first and second polymers can be at least partially entangled. In other words, in the coating film, the first polymer portion and the second polymer portion are compatible and do not separate. This makes it easier for both the first polymer and the second polymer to exert their functions.

[0019] Amine catalysts and acid catalysts have been known as compounds that have catalytic activity toward both organic and inorganic components. However, these catalysts react with the organic components of the first polymer, preventing the polymerization of the organic components themselves, which can lead to insufficient curing of the first polymer.

[0020] On the other hand, organometallic compounds do not react with organic components. They react not with the inorganic components that make up the second polymer, but with the second polymer (i.e., the condensate of the siloxane oligomer (a2)). This results in a loss of catalytic activity, suppressing subsequent condensation. In other words, excessive shrinkage of the coating film is suppressed.

[0021] This mechanism is believed to be as follows: First, the organometallic compound is hydrolyzed in the reaction system to produce a reactive intermediate. This intermediate repeatedly reacts with the siloxane oligomer (a2) to produce a silicone condensate. Furthermore, at least a portion of the organometallic compound reacts with the condensate of the siloxane oligomer (a2), thereby incorporating and immobilizing the central metal of the organometallic compound into the condensate. As a result, the catalytic activity of the organometallic compound is reduced and stabilized. This suppresses further condensation reactions of the condensate of the siloxane oligomer (a2). As a result, the occurrence of cracks is further suppressed.

[0022] Although the resin composition according to the present disclosure contains a curing catalyst (b2), the organic component and the inorganic component do not react or the reaction is suppressed, so the resin composition has a sufficient pot life. The inclusion of a specific amount of an organometallic compound as the curing catalyst (b2) also contributes to ensuring the required pot life.

[0023] [Resin composition] The coating film is formed from the following resin composition. The resin composition according to the present disclosure comprises a base component (A) and a curing agent (B). The base component (A) comprises an amino group-containing acrylic resin (a1) as an organic component and a siloxane oligomer (a2) as an inorganic component. The curing agent (B) comprises a polyepoxide (b1) and a curing catalyst (b2).

[0024] The amino group-containing acrylic resin (a1) reacts with the polyepoxide (b1) to crosslink and form a first polymer. The amino group-containing acrylic resin (a1) does not contain any reactive groups (hereinafter referred to as "first reactive groups") that can react with silanol groups, or the number of first reactive groups is less than 11% of the number of amino groups in the amino group-containing acrylic resin (a1). Therefore, the amino group-containing acrylic resin (a1) does not react with the siloxane oligomer (a2), or reacts only sparingly.

[0025] The siloxane oligomer (a2) crosslinks by self-condensing to form a siloxane bond to form a second polymer, but as described below, the siloxane oligomer (a2) does not have a group reactive with an amino group (typically an epoxy group) or a group reactive with an epoxy group (typically an amino group), and therefore does not react with the organic component.

[0026] As described above, the polyepoxide (b1) reacts with the amino group-containing acrylic resin (a1) to crosslink and form a first polymer. Since the polyepoxide (b1) does not have any first reactive groups or the number of first reactive groups is less than 10% of the number of epoxy groups in the polyepoxide (b1), the polyepoxide (b1) does not react or reacts poorly with the siloxane oligomer (a2).

[0027] The curing catalyst (b2) promotes the condensation reaction of the siloxane oligomer (a2) and the reaction between the amino group-containing acrylic resin (a1) and the polyepoxide (b1). Furthermore, when the curing catalyst (b2) is an organometallic compound, the central metal of the organometallic compound is incorporated into the second polymer and immobilized. This reduces the catalytic activity of the organometallic compound, stabilizing it. This further suppresses the condensation reaction of the siloxane oligomer during outdoor exposure.

[0028] (Amino group-containing acrylic resin (a1)) The amino group-containing acrylic resin (a1) is one of the organic components and contains one or more amino groups. The amino group-containing acrylic resin (a1) reacts with the polyepoxide (b1) to form a first polymer.

[0029] In the amino group-containing acrylic resin (a1), there are no reactive groups (first reactive groups) capable of reacting with silanol groups, or the number of first reactive groups is less than 11% of the number of amino groups in the amino group-containing acrylic resin (a1). As described above, the amount of first reactive groups present in the amino group-containing acrylic resin (a1) is small, so that the amino group-containing acrylic resin (a1) does not react with the siloxane oligomer (a2), or reacts only sparingly.

[0030] The first reactive group may be at least one selected from the group consisting of a hydroxyl group, an alkoxy group, an alkoxysilyl group, and a silanol group.

[0031] The ratio R1 of the number of first reactive groups to the number of amino groups in the amino group-containing acrylic resin (a1) can be determined from the structural formula of the amino group-containing acrylic resin (a1): the number of first reactive groups in the structural formula divided by the number of amino groups, and multiplied by 100, is the ratio R1.

[0032] The ratio R1 may be calculated from the number of amino groups and the number of first reactive groups obtained by component analysis of the amino group-containing acrylic resin. 1 The number of hydroxyl groups as first reactive groups can be determined by measuring the hydroxyl value of the amino group-containing acrylic resin. The number of alkoxy groups can be determined by measuring the hydroxyl value of the amino group-containing acrylic resin. 1 The number of silanol groups and alkoxysilyl groups in the amino group-containing acrylic resin can be calculated from the ratio of peak integral values ​​of the spectrum obtained by H-NMR measurement. 1 H-NMR or 29It can be determined from the peak integral ratio of the spectrum obtained by Si-NMR measurement or the Si concentration obtained by ICP optical emission spectroscopy.

[0033] The amine value can be determined by the following method in accordance with ASTM D2073. (1) 500 mg of amino group-containing acrylic resin (a1) is weighed out into a 200 ml Erlenmeyer flask. (2) Add approximately 50 ml of tetrahydrofuran (THF) and dissolve uniformly. (3) Add 5 to 6 drops of indicator (methyl violet solution) and stir evenly. (4) Titrate with 0.2N hydrochloric acid-ethanol solution, and the endpoint is when the solution turns bright green. (The above (3) and (4) may be replaced by potentiometric titration.)

[0034] The ratio R1 may be calculated from the mass ratio and molecular weight of the raw material monomers used in synthesizing the amino group-containing acrylic resin (a1) using the following formula: In the formula, WR11, WR12... represent the amount (g) of each monomer containing a first reactive group, n11, n12... represent the number of first reactive groups in one monomer molecule, and MR11, MR12 represent the molecular weight of each monomer, WA11, WA12... represent the amount (g) of each monomer containing an amino group, m11, m12... represent the number of amino groups in one monomer molecule, and MA11, MA12... represent the molecular weight of each monomer. TIFF0007739397000003.tif14169

[0035] The ratio R1 may be 10% or less, 5% or less, 2% or less, or 0%.

[0036] The amino group-containing acrylic resin (a1) has an amine value of 8 mgKOH / g or more and 90 mgKOH / g or less. When the amine value is 8 mgKOH / g or more, the number of crosslinking points with the polyepoxide (b1) increases, improving the water resistance and weather resistance of the resulting coating film. When the amine value is 90 mgKOH / g or less, excessive crosslinking is suppressed, thereby suppressing a decrease in flexibility. The amine value of the amino group-containing acrylic resin (a1) may be 10 mgKOH / g or more, or may be 15 mgKOH / g or more. The amine value of the amino group-containing acrylic resin (a1) may be 89 mgKOH / g or less, or may be 36 mgKOH / g or less.

[0037] The weight average molecular weight Mw of the amino group-containing acrylic resin (a1) is, for example, 5,000 or more and 200,000 or less. When the amino group-containing acrylic resin (a1) has an Mw of 5,000 or more, decomposition of the first polymer by ultraviolet light is easily suppressed. When the amino group-containing acrylic resin (a1) has an Mw of 200,000 or less, a decrease in flexibility of the coating film is easily suppressed. The Mw of the amino group-containing acrylic resin (a1) may be 10,000 or more, 20,000 or more, or 25,000 or more. The Mw of the amino group-containing acrylic resin (a1) may be 100,000 or less, 70,000 or less, or 50,000 or less.

[0038] The amino group-containing acrylic resin (a1) is mixed with the siloxane oligomer (a2) as a polymer. The resin composition may contain two or more amino group-containing acrylic resins (a1). The two or more amino group-containing acrylic resins (a1) are mixed with the siloxane oligomer (a2) as polymers, respectively. The two or more amino group-containing acrylic resins (a1) may be mixed with the siloxane oligomer (a2) as a mixture of two or more polymers.

[0039] The mass proportion of the amino group-containing acrylic resin (a1) in the total solid content of the amino group-containing acrylic resin (a1), siloxane oligomer (a2), and polyepoxide (b1) is, for example, 10% by mass or more and 80% by mass or less. When the mass proportion of the amino group-containing acrylic resin (a1) is 10% by mass or more, the properties of the first polymer are easily exhibited. When the mass proportion of the amino group-containing acrylic resin (a1) is 80% by mass or less, the properties of the second polymer are easily exhibited. The mass proportion of the amino group-containing acrylic resin (a1) may be 20% by mass or more, 30% by mass or more, 40% by mass or more, or 50% by mass or more. The mass proportion of the amino group-containing acrylic resin (a1) may be 77% by mass or less, 73% by mass or less, or 70% by mass or less.

[0040] The amino group may be primary, secondary, or tertiary. The amino group-containing acrylic resin (a1) may have at least one tertiary amino group per molecule. This increases the crosslink density of the organic component, further improving durability. The number of tertiary amino groups may be two or more, or three or more.

[0041] The amino group-containing acrylic resin (a1) is usually a copolymer of raw material monomers including an amino group-containing polymerizable monomer (m1) and another polymerizable monomer (m2) copolymerizable with the amino group-containing polymerizable monomer (m1). By using a polymerizable monomer containing a tertiary amino group, one or more tertiary amino groups can be introduced into the amino group-containing acrylic resin (a1).

[0042] The amino group-containing polymerizable monomer (m1) may be at least one selected from the group consisting of tertiary amino group-containing monomers such as N,N-dimethylaminoethyl (meth)acrylate (DMAEMA), N,N-diethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, N,N-dimethylaminobutyl (meth)acrylate, and N,N-dimethylaminopropyl (meth)acrylamide; and secondary amino group-containing monomers such as Nt-butylaminoethyl (meth)acrylate. The term "(meth)acrylate" encompasses both acrylate and methacrylate.

[0043] Other polymerizable monomers (m2) include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, dodecyl (meth)acrylate, lauryl (meth)acrylate, ) acrylate), tridecyl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, t-butylcyclohexyl (meth)acrylate, cyclododecyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, tricyclodecanyl (meth)acrylate, and other alkyl (meth)acrylates; benzyl (meth)acrylate, Aromatic ring-containing polymerizable monomers such as styrene, α-methylstyrene, and vinyltoluene; perfluoroalkyl (meth)acrylates such as perfluorobutylethyl (meth)acrylate and perfluorooctylethyl (meth)acrylate; polymerizable monomers having a fluorinated alkyl group such as fluoroolefin; polymerizable monomers having a photopolymerizable functional group such as a maleimide group; vinyl compounds such as N-vinylpyrrolidone, ethylene, butadiene, chloroprene, vinyl propionate, and vinyl acetate; carboxy group-containing polymerizable monomers such as (meth)acrylic acid, maleic acid, crotonic acid, and β-carboxyethyl acrylate; nitrogen-containing polymerizable monomers such as (meth)acrylonitrile and (meth)acrylamide; epoxy group-containing polymerizable monomers such as glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, 3,4-epoxycyclohexylethyl (meth)acrylate, 3,4-epoxycyclohexylpropyl (meth)acrylate, and allyl glycidyl ether;Examples of the other polymerizable monomers (m2) include alkoxy group-containing polymerizable monomers such as N-methoxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, alkoxyalkyl(meth)acrylates such as methoxyethyl(meth)acrylate, methoxypropyl(meth)acrylate, ethoxyethyl(meth)acrylate, and ethoxypropyl(meth)acrylate, and polyalkylene glycol monoalkoxy(meth)acrylates such as polyethylene glycol monomethoxy(meth)acrylate; and carbonyl group-containing polymerizable monomers such as acrolein, diacetone acrylamide, diacetone methacrylamide, acetoacetoxyethyl methacrylate, formylstyrene, and vinyl alkyl ketones having 4 to 7 carbon atoms (e.g., vinyl methyl ketone, vinyl ethyl ketone, and vinyl butyl ketone). The other polymerizable monomers (m2) may be used singly or in combination of two or more.

[0044] A polymerizable monomer having a first reactive group may also be used as the raw material monomer, provided that the polymerizable monomer having the first reactive group is used so that the above-mentioned ratio R1 is less than 11%.

[0045] Examples of the polymerizable monomer containing a first reactive group include polymerizable monomers having an alkoxysilyl group, such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, γ-(meth)acryloyloxypropyltrimethoxysilane, and γ-(meth)acryloyloxypropyltriethoxysilane; 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 3-hydroxypropyl(meth)acrylate, and 4-hydroxybutyl(meth)acrylate. other hydroxyl group-containing polymerizable monomers such as monoesters of (meth)acrylic acid and dihydric alcohols having 2 to 8 carbon atoms, ε-caprolactone-modified products of the monoesters of (meth)acrylic acid and dihydric alcohols having 2 to 8 carbon atoms, N-hydroxymethyl(meth)acrylamide, allyl alcohol, (meth)acrylates having a polyoxyethylene chain with a hydroxyl group at the molecular terminal, and silanol group-containing polymerizable monomers such as dimethylvinylsilanol and methylphenylvinylsilanol. The monomers having a first reactive group may be used singly or in combination of two or more.

[0046] (Polyepoxide (b1)) The polyepoxide (b1) is one of the organic components and has at least two epoxy groups (oxirane rings) in one molecule. The polyepoxide (b1) reacts with the amino group-containing acrylic resin (a1) to form a first polymer.

[0047] In the polyepoxide (b1), there are no first reactive groups capable of reacting with the silanol groups, or the number of first reactive groups is less than 10% of the number of epoxy groups in the polyepoxide (b1). As such, the amount of first reactive groups present in the polyepoxide (b1) is small, so that the polyepoxide (b1) does not react with the siloxane oligomer (a2), or the reaction is difficult.

[0048] The ratio R2 of the number of first reactive groups to the number of epoxy groups in the polyepoxide (b1) can be determined from the structural formula of the polyepoxide (b1): the number of first reactive groups in the structural formula divided by the number of epoxy groups, and multiplied by 100, is the ratio R2.

[0049] The ratio R2 may be calculated from the number of epoxy groups and first reactive groups obtained by component analysis of the polyepoxide. 1 The epoxy equivalent can be determined by measuring the peak integral ratio of the spectrum obtained by H-NMR measurement or the epoxy equivalent of the polyepoxide. The number of first reactive groups can be determined in the same manner as above. The epoxy equivalent can be determined, for example, in accordance with JIS K 7236:2001.

[0050] The ratio R2 may be calculated from the mass ratio and molecular weight of the raw material monomers used in the synthesis of polyepoxide (b1) using the following formula: In the formula, WR21, WR22... represent the amount (g) of each monomer containing a first reactive group, n21, n22... represent the number of first reactive groups in one molecule of the monomer, and MR21, MR22 represent the molecular weight of each monomer, WE11, WE12... represent the amount (g) of each monomer containing an epoxy group, m21, m22... represent the number of epoxy groups in one molecule of the monomer, and ME11, ME12... represent the molecular weight of each monomer. TIFF0007739397000004.tif14168

[0051] The ratio R2 may be 9.5% or less, 5% or less, 2% or less, or 0%.

[0052] The polyepoxide (b1) has an epoxy equivalent of 100 g / eq or more and 1,500 g / eq or less. When the epoxy equivalent is 100 g / eq or more, the number of crosslinking points with the amino group-containing acrylic resin (a1) increases, improving the water resistance and weather resistance of the resulting coating film. When the epoxy equivalent is 1,500 g / eq or less, excessive crosslinking is suppressed, preventing a decrease in flexibility. The epoxy equivalent of the polyepoxide (b1) may be 120 g / eq or more, or 130 g / eq or more. The epoxy equivalent of the polyepoxide (b1) may be 1,450 g / eq or less, 500 g / eq or less, or 400 g / eq or less.

[0053] The weight average molecular weight Mw of the polyepoxide (b1) is, for example, 200 or more and 100,000 or less. When the Mw of the polyepoxide (b1) is 200 or more, decomposition of the first polymer by ultraviolet light is easily suppressed. When the Mw of the polyepoxide (b1) is 100,000 or less, a decrease in flexibility of the coating film is easily suppressed. The Mw of the polyepoxide (b1) may be 250 or more. The Mw of the polyepoxide (b1) may be 50,000 or less, or may be 30,000 or less.

[0054] The mass proportion of the polyepoxide (b1) in the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is, for example, 0.8 mass% or more and 80 mass% or less. When the mass proportion of the polyepoxide (b1) is 0.81 mass% or more, the properties of the first polymer are easily exhibited. When the mass proportion of the polyepoxide (b1) is 80 mass% or less, the properties of the second polymer are easily exhibited. The mass proportion of the polyepoxide (b1) may be 1.0 mass% or more. The mass proportion of the polyepoxide (b1) may be 60 mass% or less, 40 mass% or less, 30 mass% or less, or 20 mass% or less.

[0055] The polyepoxide (b1) may have at least one glycidyl group in one molecule. The number of glycidyl groups in one molecule of the polyepoxide (b1) may be 2 or more. All of the epoxy groups in one molecule of the polyepoxide (b1) may be glycidyl groups.

[0056] Examples of the polyepoxide (b1) include glycidyl group-containing acrylic resins, glycidyl ether-type polyepoxides, glycidyl ester-type polyepoxides, glycidyl amine-type polyepoxides, and alicyclic polyepoxides. Among these, in terms of flexibility and weather resistance, glycidyl group-containing acrylic resins and glycidyl ether-type polyepoxides may be used.

[0057] The glycidyl group-containing acrylic resin is a copolymer of raw material monomers including an epoxy group-containing polymerizable monomer and another polymerizable monomer copolymerizable with the epoxy group-containing polymerizable monomer. Specific examples of the epoxy group-containing polymerizable monomer are listed as raw material monomers for the amino group-containing acrylic resin (a1). The epoxy group-containing polymerizable monomer may be used alone or in combination of two or more. Specific examples of the other polymerizable monomer include raw material monomers for the amino group-containing acrylic resin (a1) other than the epoxy group-containing polymerizable monomer. The other polymerizable monomer may be used alone or in combination of two or more. However, the polymerizable monomer containing the first reactive group is used so that the above ratio R2 is less than 10%.

[0058] Examples of glycidyl ether type polyepoxides include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, trimethylolpropane polyglycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, and sorbitol polyglycidyl ether.

[0059] Examples of glycidyl ester type polyepoxides include phthalic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, diglycidyl-p-oxybenzoic acid, glycidyl ether-glycidyl ester of salicylic acid, and dimer acid glycidyl ester.

[0060] Examples of glycidylamine type polyepoxides include triglycidyl isocyanurate, N,N'-diglycidyl derivatives of cyclic alkylene ureas, N,N,O-triglycidyl derivatives of p-aminophenol, and N,N,O-triglycidyl derivatives of m-aminophenol.

[0061] Examples of alicyclic polyepoxides include 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-2-methylcyclohexylmethyl-3,4-epoxy-2-methylcyclohexanecarboxylate, bis(3,4-epoxycyclohexyl)adipate, bis(3,4-epoxycyclohexylmethyl adipate), bis(3,4-epoxy-6-methylcyclohexylmethyl)adipate, 2-(3,4-epoxycyclohexyl-5,5-spiro-3,4-epoxycyclohexanone-meta-dioxane), and bis(2,3-epoxycyclopentyl)ether.

[0062] The resin composition may contain two or more types of polyepoxides (b1).

[0063] (Siloxane oligomer (a2)) The siloxane oligomer (a2) is an inorganic component that self-condenses to form a second polymer.

[0064] The siloxane oligomer (a2) is represented by the following general formula (x): [ka] (In the formula, R 3 represents independently in each structural unit a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a single bond, R 4 represents independently in each structural unit an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 15 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or -O-; m is an integer from 0 to 200. and a structural unit X represented by the following general formula (y): [ka] (In the formula, R 5 and R 6 each independently in each repeating unit represents an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms; n is an integer from 0 to 200. and a structural unit Y represented by The terminal group has at least one selected from the group consisting of a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms.

[0065] As can be seen from the general formulas (x) and (y) above, the siloxane oligomer (a2) does not have a second reactive group (typically an amino group) that reacts with an epoxy group or a third reactive group (typically an epoxy group) that reacts with an amino group. Therefore, the reaction of the siloxane oligomer (a2) with the amino-group-containing acrylic resin (a1) and the polyepoxide (b1) is further suppressed. Examples of the second reactive group include an amino group and a carboxy group. Examples of the third reactive group include an epoxy group and a halogen group.

[0066] m+n is an integer of 2 to 200. When m+n is 2 or more, the second polymer exhibits its properties as an inorganic component. When m+n is 200 or less, the molecular weight of the second polymer is prevented from becoming excessively large, making it easier to mix with the first polymer and improving compatibility. m+n may be 3 or more, or 5 or more. m+n may be 150 or less, 60 or less, 15 or less, or 10 or less.

[0067] The value m+n is determined from the weight average molecular weight of the siloxane oligomer (a2), the ratio of the structural units X and Y constituting the siloxane oligomer, and their molecular weights. The weight average molecular weight can be measured, for example, by gel permeation chromatography (GPC). The ratio of the structural units X and Y constituting the siloxane oligomer, and their molecular weights can be determined by the formulation or 29 It can be calculated from the peak integral value of the spectrum obtained by Si-NMR measurement.

[0068] The resin composition may contain two or more types of siloxane oligomer (a2), in which case m+n is calculated as the average value of the mixture of two or more types of siloxane oligomer.

[0069] When m≧1, the siloxane oligomer (a2) has at least a structural unit X. In the structural unit X, R 3 When R is a single bond, the siloxane oligomer (a2) has a branched three-dimensional structure. 3The oxygen atom bonded to is bonded to the Si atom of another structural unit X.

[0070] When m≧1, the siloxane oligomer (a2) has at least a structural unit X. In the structural unit X, R 4 When R is -O-, the siloxane oligomer (a2) has a branched three-dimensional structure. 4 The oxygen atom of is bonded to the Si atom of another structural unit X.

[0071] When n≧1, the siloxane oligomer (a2) has at least a structural unit Y. When n≧1 and m=0, the siloxane oligomer (a2) has a linear structure.

[0072] In the non-terminal structural unit X, R 3 is a single bond and R 4 When m is -O-, each of the four bonds of the Si atom can be bonded to an oxygen atom. Such a Si atom is said to be tetrafunctional. When m≧1, the siloxane oligomer (a2) can contain a structural unit having a tetrafunctional Si atom (hereinafter, sometimes referred to as a Q unit). The siloxane oligomer (a2) containing a Q unit can be obtained by using a silane compound having a Si atom bonded to four alkoxy groups (e.g., having 1 to 5 carbon atoms) as one of the raw material monomers.

[0073] In the non-terminal structural unit X, R 3 is a single bond, or R 4 When m is -O-, three of the bonds of the Si atom can be bonded to oxygen atoms. Such a Si atom is said to be trifunctional. When m≧1, the siloxane oligomer (a2) can contain a structural unit having a trifunctional Si atom (hereinafter, sometimes referred to as a T unit). The siloxane oligomer (a2) containing a T unit can be obtained by using a silane compound having a Si atom bonded to three alkoxy groups (e.g., having 1 to 5 carbon atoms) as one of the raw material monomers.

[0074] In the non-terminal structural unit Y, two of the bonds of the Si atom can each be bonded to an oxygen atom. Such a Si atom is said to be bifunctional. When n≧1, the siloxane oligomer (a2) can contain a structural unit having a bifunctional Si atom (hereinafter sometimes referred to as a D unit). The siloxane oligomer (a2) containing a D unit can be obtained by using a silane compound having a Si atom bonded to two alkoxy groups (e.g., having 1 to 5 carbon atoms) as one of the raw material monomers.

[0075] In the terminal structural unit Y, one of the bonds of the Si atom can be bonded to an oxygen atom. Such a Si atom is called monofunctional. When n≧1, the siloxane oligomer (a2) can contain a structural unit having a monofunctional Si atom (hereinafter sometimes referred to as an M unit). The Si atom in the M unit is bonded to an alkyl group having 1 to 5 carbon atoms as a terminal group.

[0076] The mass proportion of the siloxane oligomer (a2) in the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is, for example, 10% by mass or more and 90% by mass or less. When the mass proportion of the siloxane oligomer (a2) is 10% by mass or more, the properties of the second polymer are more easily exhibited. When the mass proportion of the siloxane oligomer (a2) is 90% by mass or less, the properties of the first polymer are more easily exhibited. The mass proportion of the siloxane oligomer (a2) may be 15% by mass or more, 20% by mass or more, or 25% by mass or more. The mass proportion of the siloxane oligomer (a2) may be 70% by mass or less, 50% by mass or less, or 40% by mass or less.

[0077] (Curing catalyst (b2)) The curing catalyst (b2) promotes the condensation reaction between the siloxane oligomer (a2) and the amino group-containing acrylic resin (a1) and the polyepoxide (b1). The curing catalyst (b2) contains an organometallic compound. The mass ratio of the organometallic compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass% or more and 30 mass% or less. This allows the first polymer and the second polymer to be formed simultaneously. This also extends the pot life of the coating resin composition and the coating. Furthermore, the central metal of the organometallic compound is incorporated and fixed in the condensate of the siloxane oligomer (a2). This reduces the catalytic activity of the organometallic compound and stabilizes it. As a result, the condensation reaction of the condensate of the siloxane oligomer (a2) during outdoor exposure is suppressed, further suppressing the occurrence of cracks.

[0078] The organometallic compound may contain at least one selected from the group consisting of alkoxide compounds, chelate compounds and acylate compounds of metals with a coordination number of 2 to 8.

[0079] The metal having a coordination number of 2 to 8 may include at least one selected from the group consisting of titanium, tin, zinc, aluminum, nickel, iron, and zirconium. The metal having a coordination number of 2 to 8 may include at least one selected from the group consisting of titanium, tin, aluminum, and zirconium. The metal having a coordination number of 2 to 8 may include at least one selected from the group consisting of titanium, zirconium, and aluminum.

[0080] In particular, the curing catalyst (b2) may contain at least one selected from the group consisting of an organotitanium compound, an organozirconium compound, and an organoaluminum compound. The curing catalyst (b2) may contain at least one selected from the group consisting of an organotitanium compound and an organozirconium compound, and an organoaluminum compound.

[0081] The organotitanium compounds are The following general formula (C t1 ): Ti(OR t1 )4(C t1 ) (In the formula, OR t1 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearoxy group, an isostearic acid group, or an acetylacetonate group), The following general formula (C t2 ): Ti(OR t2 ) mt (L t1 ) 4-mt (C t2 ) (In the formula, OR t2 each independently represents an alkyl group having 2 to 4 carbon atoms, L t1 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group, mt is an integer from 1 to 3, and The following general formula (C t3 ): Ti(L t2 )4(C t3 ) (In the formula, L t2 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group. The compound may contain at least one selected from the group consisting of compounds represented by the following formula:

[0082] General formula (C t1 The compound represented by the general formula (C) is an example of a titanium alkoxide compound or acylate compound. t2 The compound represented by the general formula (C) is an example of an alkyl chelate compound of titanium. t3) is an example of a titanium chelate compound.

[0083] OR t1 , OR t2 may each be an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, or a stearoxy group. t1 may be the same or different. t1 may each be an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, or a stearoxy group. t2 may be the same or different. t2 may be an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, or a stearoxy group. The alkyl group constituting the alkoxy group may be linear or branched. The alkyl group constituting the alkoxy group may be an isopropoxy group or an n-butoxy group.

[0084] L t1 , L t2 may each be an acetylacetonato group or an ethylacetonato group. t1 may be the same or different. t1 Each of L may be an acetylacetonato group or an ethylacetonato group. t2 may be the same or different. t2 may each be an acetylacetonato group or an ethylacetonato group.

[0085] The organic zirconium compound is The following general formula (C z1 ): Zr(OR z1 )4(Cz1) (In the formula, OR z1 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearic acid group, or an octylic acid group), The following general formula (Cz2 ): Zr(OR z2 ) mz (L z1 ) 4-mz (C z2 ) (In the formula, OR z2 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearic acid group, or an octylic acid group, L z1 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group, mz is an integer from 1 to 3, and The following general formula (C z3 ): Zr(L z2 )4(C z3 ) (In the formula, L z2 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group. The compound may contain at least one selected from the group consisting of compounds represented by the following formula:

[0086] General formula (C z1 The compound represented by the general formula (C) is an example of an alkoxide compound or an acylate compound of zirconium. z2 The compound represented by the general formula (C) is an example of an alkyl chelate compound of zirconium. z3 ) is an example of a zircon chelate compound.

[0087] OR z1 and OR z2 may each be an alkoxy group having 2 to 4 carbon atoms or an octylic acid group. z1may be the same or different. z1 may each be an alkoxy group having 2 to 4 carbon atoms or an octylic acid group. z2 may be the same or different. z2 may be an alkoxy group having 2 to 4 carbon atoms or an octylic acid group. The alkyl group constituting the alkoxy group may be linear or branched. The alkyl group constituting the alkoxy group may be an n-propoxy group, an isopropoxy group, or an n-butoxy group.

[0088] L z1 and L z2 may each be an acetylacetonato group or an ethylacetonato group. z1 may be the same or different. z1 Each of L may be an acetylacetonato group or an ethylacetonato group. z2 may be the same or different. z2 may each be an acetylacetonato group or an ethylacetonato group.

[0089] Organoaluminum compounds include The following general formula (C a1 ): Al(OR a1 )3 (In the formula, OR a1 each independently represents an alkoxy group having 1 to 4 carbon atoms), The following general formula (C a2 ): Al(OR a2 ) ma (L a1 ) 3-ma (C a2 ) (In the formula, OR a2 each independently represents an alkoxy group having 2 to 4 carbon atoms, L a1each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, a proponylacetonato group, or a stearylacetonato group, ma is an integer from 1 to 3, and The following general formula (C a3 ): Al(L a2 )3(C a3 ) (In the formula, L a2 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, a proponylacetonato group, or a stearylacetonato group. The compound may contain at least one selected from the group consisting of compounds represented by the following formula:

[0090] General formula (C a1 The compound represented by the general formula (C) is an example of an aluminum alkoxide compound or an aluminum acylate compound. a2 The compound represented by the general formula (C) is an example of an aluminum alkyl chelate compound. a3 ) is an example of an aluminum chelate compound.

[0091] OR a1 may each independently be an alkoxy group having 2 to 4 carbon atoms, or may be an alkoxy group having 2 or 3 carbon atoms. a1 may be the same or different. a1 may be an alkyl group having 2 to 4 carbon atoms, or may be an alkyl group having 2 or 3 carbon atoms. The alkyl group constituting the alkoxy group may be linear or branched.

[0092] OR a2may each independently be an alkoxy group having 2 to 4 carbon atoms, an alkoxy group having 2 or 3 carbon atoms, or an alkoxy group having 3 carbon atoms. a2 may be the same or different. a2 may be an alkoxy group having 2 to 4 carbon atoms, an alkoxy group having 2 or 3 carbon atoms, or an alkoxy group having 3 carbon atoms. The alkyl group constituting the alkoxy group may be linear or branched.

[0093] L a1 and L a2 may each be an acetylacetonato group, an ethylacetonato group, or a stearylacetonato group. a1 may be the same or different. a1 Each of L may be an acetylacetonato group, an ethylacetonato group, or a stearylacetonato group. a2 may be the same or different. a2 may each be an acetylacetonato group, an ethylacetonato group, or a stearylacetonato group.

[0094] Specific examples of the organotin compound include diacetyltin diacetate, dibutyltin dilaurate, dibutyltin diacetate, dioctyltin dilaurate, diacetyltin dioctate, tin octoate, dibutyltin diacetate, and dibutyltin dioctate.

[0095] Specific examples of the organoaluminum compound include aluminum trimethoxide, aluminum triethoxide, aluminum tris(acetylacetonate), aluminum tri-n-butoxide, aluminum tris(ethyl acetoacetate), aluminum diisopropoxy(ethyl acetylacetonate), aluminum diisopropoxymono(sec-butylate), aluminum tris(sec-butylate), and aluminum diisopropoxy(stearyl acetylacetonate).

[0096] Specific examples of organic titanium compounds include titanium tetraethoxide, titanium tetraisopropoxide, titanium tetra-normal-butoxide, titanium tetrakis(2-ethylhexyloxide), titanium diisopropoxybis(acetylacetonate), titanium diisopropoxybis(ethyl acetylacetonate), titanium tetra(acetylacetonate), and titanium isopropoxytris(isostearate).

[0097] Specific examples of the organic zirconium compound include zirconium tetramethoxide, zirconium tetraethoxide, zirconium tetra-normal propoxide, zirconium tetra-normal butoxide, zirconium tetra(acetylacetonate), zirconium tri-normal butoxymono(acetylacetonate), zirconium di-normal butoxybis(ethyl acetylacetonate), and zirconium dibutoxybis(acetylacetonate).

[0098] A specific example of the organozinc compound is zinc naphthenate.

[0099] The mass proportion of the curing catalyst (b2) relative to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass% or more and 30 mass% or less. The mass proportion of the curing catalyst (b2) may be 0.2 mass% or more, 0.5 mass% or more, or 1 mass% or more. The mass proportion of the curing catalyst (b2) may be 28 mass% or less, 25 mass% or less, 20 mass% or less, 10 mass% or less, or 8 mass% or less.

[0100] In Aspect 1 in which the curing catalyst (b2) contains an organotitanium compound and an organoaluminum compound, the mass proportion of the organotitanium compound relative to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) may be from 0.1 to 12 mass%, and the mass proportion of the organoaluminum compound relative to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) may be from 0.1 to 20 mass%.

[0101] The mass proportion of the organotitanium compound in Aspect 1 may be 0.5 mass% or more, 1.0 mass% or more, or 1.5 mass% or more. The mass proportion of the organotitanium compound may be 10.0 mass% or less, or 5.0 mass% or less.

[0102] The mass proportion of the organoaluminum compound in Aspect 1 may be 2.0 mass% or more, 4.0 mass% or more, or 5.0 mass% or more. The mass proportion of the organoaluminum compound may be 19.5 mass% or less, or 12.0 mass% or less.

[0103] In embodiment 2, in which the curing catalyst (b2) contains an organic zirconium compound and an organic aluminum compound, the mass proportion of the organic zirconium compound relative to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) may be from 0.1 to 12 mass%, and the mass proportion of the organic aluminum compound relative to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) may be from 0.1 to 20 mass%.

[0104] The mass percentage of the organozirconium compound in Aspect 2 may be 0.5 mass% or more, or 2.0 mass% or more, and 11.0 mass% or less, or 6.0 mass% or less.

[0105] In Aspect 2, the mass proportion of the organoaluminum compound may be 2.0 mass% or more, or 4.0 mass% or more. The mass proportion of the organoaluminum compound may be 18.0 mass% or less, or 11.0 mass% or less.

[0106] The weight average molecular weight Mw of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) can be measured using GPC (for example, Tosoh Corporation, product name: HLC-8220GPC column, Tosoh Corporation, product names: TSK-GEL SUPER HZM-H, TSK-GEL SUPER HZ3000, TSK-GEL SUPER HZ2000) and tetrahydrofuran or chloroform as a solvent, and can be calculated in terms of polystyrene.

[0107] [paint] The present disclosure encompasses a coating material containing the resin composition described above. The coating material of the present disclosure provides a coating film that inhibits cracking in outdoor environments. Therefore, the coating material of the present disclosure is primarily suitable for coating substrates that are used or installed outdoors. Examples of such substrates include bridges, buildings, tanks, plants, towers, roads, tunnels, ships, vehicles, and roofs. Examples of materials for the substrate include metals (e.g., steel such as steel plate, galvanized steel, stainless steel, and aluminum), ceramic materials (e.g., concrete, mortar, slate, and slate), plastics, vinyl sheets, paper, wood, and glass.

[0108] (organic solvent) The paint may contain a Class 3 organic solvent as defined by the Industrial Safety and Health Act. Class 3 organic solvents are also called weak solvents and generally have low dissolving power. The Class 3 organic solvent is used to adjust the paint to the desired viscosity. The solid content of the paint is appropriately set depending on the application, coating method, etc.

[0109] Class 3 organic solvents include gasoline, coal tar naphtha (including solvent naphtha), petroleum ether, petroleum naphtha, petroleum benzine, turpentine oil, and mineral spirits (including mineral thinner, petroleum spirits, white spirits, and mineral turpentine). These can be used alone or in combination.

[0110] The paint may contain organic solvents other than the third-class organic solvents. Examples of other organic solvents include hydrocarbon solvents such as n-butane, n-hexane, n-heptane, n-octane, cyclopentane, cyclohexane, and cyclobutane; aromatic solvents such as toluene and xylene; ethylene glycol monoisopropyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol mono-t-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether, and propylene glycol monomethyl ether. Examples of suitable solvents include ether solvents such as glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and dioxane; ester solvents such as methyl acetate, ethyl acetate, n-butyl acetate, isobutyl acetate, methyl acetoacetate, ethylene glycol monomethyl ether acetate, and butyl carbitol acetate; ketone solvents such as acetone, acetylacetone, diacetone alcohol, methyl ethyl ketone, methyl isobutyl ketone, and diisobutyl ketone; and alcohol solvents such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, isobutanol, and n-pentanol. These may be used alone or in combination of two or more.

[0111] (pigment) The paint may contain a pigment. Examples of pigments include color pigments, anti-rust pigments, and extender pigments. These may be used alone or in combination of two or more.

[0112] (additives) The coating material may contain various additives as needed. Examples of additives include ultraviolet absorbers, viscosity modifiers, antioxidants, antifoaming agents, surface conditioners, pinhole inhibitors, silane coupling agents, and pigment dispersants. These may be used alone or in combination of two or more.

[0113] <Second compound> The second compound containing both the first reactive group and the second reactive group in one molecule is preferably not contained in the resin composition or the coating material, or its content is small. The mass ratio of the second compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) may be 1 mass% or less, 0.8 mass% or less, 0.5 mass% or less, or 0 mass%.

[0114] Examples of the second compound include an amino group-containing silane coupling agent and a carboxy group-containing silane coupling agent.

[0115] The number of second reactive groups in the second compound may be less than 11% of the number of amino groups in the amino group-containing acrylic resin (a1), since this has little effect on the reactivity between the amino group-containing acrylic resin (a1) and the polyepoxide (b1).

[0116] The ratio R3 of the number of second reactive groups in the second compound to the number of amino groups in the amino group-containing acrylic resin (a1) can be determined in the same manner as the ratio R1.

[0117] When calculating the ratio R3 using the mass ratios and molecular weights of the raw material monomers used in synthesizing the amino group-containing acrylic resin (a1), the following formula can be referenced. In the formula, WR31 and WR32... represent the respective amounts (g) of the second compounds, n31 and n32... represent the number of second reactive groups in one molecule of the second compound, and MR31 and MR32 represent the respective molecular weights of the second compounds. WA11, WA12..., m11, m12..., MA11, MA12... are the same as those in the formula for calculating the ratio R1. TIFF0007739397000007.tif14169

[0118] <Third compound> The third compound containing both the first reactive group and the third reactive group in one molecule is preferably not contained in the resin composition or the coating material, or its content is small. The mass ratio of the third compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) may be 1 mass% or less, 0.8 mass% or less, 0.5 mass% or less, or 0 mass%.

[0119] Examples of the third compound include an epoxy-containing silane coupling agent and a halogen-containing silane coupling agent.

[0120] The number of third reactive groups in the third compound may be less than 10% of the number of epoxy groups in the polyepoxide (b1), since this has little effect on the reactivity between the amino group-containing acrylic resin (a1) and the polyepoxide (b1).

[0121] The ratio R4 of the number of third reactive groups in the third compound to the number of epoxy groups in the polyepoxide (b1) can be determined in the same manner as the ratio R1.

[0122] When calculating the ratio R4 using the mass ratios and molecular weights of the raw material monomers used in the synthesis of polyepoxide (b1), the following formula can be referenced. In the formula, WR41 and WR42... represent the respective amounts (g) of the third compounds, n41 and n42... represent the number of third reactive groups in one molecule of the third compound, and MR41 and MR42 represent the respective molecular weights of the third compounds. WE11, WE12..., m21, m22..., ME11, and ME12... are the same as those used in the formula for calculating the ratio R2. TIFF0007739397000008.tif14169

[0123] <4th compound> The resin composition and the coating material do not contain any of the first, second, and third reactive groups, and may contain a fourth compound other than the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1). The resin composition and the coating material do not necessarily contain a fourth compound.

[0124] The mass proportion of the fourth compound relative to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) may be 30 mass% or less, 10 mass% or less, 5 mass% or less, or 0 mass%.

[0125] Examples of the fourth compound include olefin resin, urethane resin, and fluororesin.

[0126] (Paint preparation method) The coating material according to the present disclosure can be prepared by a method commonly used by those skilled in the art. The base component (A) is prepared by mixing the above-mentioned amino group-containing acrylic resin (a1) and siloxane oligomer (a2) with other components as needed. The curing agent (B) is prepared separately by mixing at least the above-mentioned polyepoxide (b1) and curing catalyst (b2) with other components as needed. The coating material is prepared by mixing the base component (A) and curing agent (B) with other components as needed. For mixing, a commonly used mixing device such as a paint shaker or mixer is used.

[0127] (Painting method) The coating method is appropriately selected depending on the shape of the object to be coated, etc. Examples of coating methods include brush coating, roller coating, spray coating, and flow coating.

[0128] [Coating] The coating film of the present disclosure is formed from the above-described resin composition, and comprises a first polymer portion formed from a reaction product of an amino group-containing acrylic resin (a1) and a polyepoxide (b1), and a second polymer portion formed from a polymer of a siloxane oligomer (a2) polymerized in the presence of a curing catalyst (b2) containing an organometallic compound, and independent of the first polymer portion, wherein at least a portion of the first polymer portion and at least a portion of the second polymer portion are entangled, and the second polymer portion contains a metal derived from the organometallic compound.

[0129] The coating film has a gloss retention of 80% or more according to JIS K5659 7.21 after undergoing an outdoor exposure test in Miyakojima, Japan, for 1.5 years at an angle of 20° to the horizontal, facing the equatorial plane, according to JIS K5600-7-6. The gloss retention may be 83% or more, or 85% or more.

[0130] Furthermore, the first and second polymer segments are substantially independent of each other. Therefore, the coating film can exhibit both the properties of an organic component (e.g., flexibility) and the properties of an inorganic component (e.g., resistance to ultraviolet light and heat). This suppresses cracking in outdoor environments. Additionally, since the metal derived from the organometallic compound is incorporated into the second polymer segment, the catalytic activity of the organometallic compound is reduced and stabilized. This suppresses further condensation reactions of the condensate of the siloxane oligomer (a2). As a result, cracking is further suppressed.

[0131] The first and second polymer portions are substantially independent of each other but are formed within the same system. Therefore, the two polymer portions are at least partially entangled, and the first and second polymer portions are compatible and not separated. Therefore, the properties of the organic and inorganic components are exhibited throughout the entire coating film, rather than just in part, further improving the durability of the coating film. Furthermore, the appearance of the resulting coating film is also improved. The two polymer portions are entangled, for example, in a network-like structure. The network structure formed can be a semi-interpenetrating polymer network or an interpenetrating polymer network.

[0132] According to the Glossary of Fundamental Terms in Polymer Science by the International Union of Pure and Applied Chemistry (IUPAC) Commission on Macromolecular Nomenclature, a "semi-interpenetrating polymer network (SIPN)" is "a polymer (see Definition 2.2) consisting of one or more networks (see Definition 1.58) and one or more linear (see Definition 1.32) or branched polymers (see Definition 1.33), in which at least some of the linear or branched polymers penetrate at least one of the networks on a molecular scale." Note: Semi-interpenetrating polymer networks are distinguished from interpenetrating polymer networks because, in principle, the constituent linear or branched polymers can be separated from the constituent polymer networks without breaking chemical bonds. That is, semi-interpenetrating polymer networks are polymer blends."

[0133] Similarly, an "interpenetrating polymer network (IPN)" "is a polymer (see Definition 2.2) in which two or more networks (see Definition 1.58) are at least partially interwoven on the molecular scale and are not covalently connected to one another but cannot be separated without breaking chemical bonds." Note: "A mixture of two or more preformed polymer networks is not an IPN."

[0134] The compatibility of the first polymer portion and the second polymer portion can be confirmed, for example, by the Tg of the coating film, the number of peaks in the loss tangent (tan δ) of the coating film, or a transmission electron microscope (TEM) image of the coating film surface. (Method 1) The first polymer portion and the second polymer portion can be considered to be compatible when the Tg of the coating film is between the Tg1 of a coating film formed solely from the first polymer and the Tg2 of a coating film formed solely from the second polymer, and the number of tan δ peaks is one, or (Method 2) when no sea-island structure is observed in the TEM image. The compatibility of the first polymer portion and the second polymer portion can be confirmed by at least one of the above two methods.

[0135] Tan δ is measured in accordance with the tensile vibration-non-resonance method of JIS-K7244-4:1999. The measurement is carried out under conditions of a temperature rise rate of 2°C / min and a frequency of 8 Hz. Tan δ can be measured using a dynamic viscoelasticity measuring device (for example, Rheogel E-4000, manufactured by UBM Corporation).

[0136] Tan δ is used as an index of Tg. In a graph where the horizontal axis is temperature and the vertical axis is tan δ, the temperature at which tan δ reaches its peak is considered to be Tg.

[0137] The thickness of the coating film is appropriately set depending on the type of substrate, the environment of use, etc. The dry thickness of the coating film is, for example, 20 μm or more and 1,000 μm or less. [Example]

[0138] The present invention will be described in more detail below using examples, but the present invention is not limited to these examples. In the examples, "parts" and "%" are by mass unless otherwise specified.

[0139] [Synthesis example of amino group-containing acrylic resin (a1)] A reaction vessel equipped with a thermometer, thermostat, stirrer, reflux condenser, and dropping device was charged with 35 parts of a third-class organic solvent (A Solvent (trade name), manufactured by ENEOS Corporation) and heated to 115°C while aerating nitrogen gas. Separately, a monomer mixture was prepared by mixing the raw material monomers shown in Table 1. Furthermore, an initiator mixture was prepared by mixing 1.5 parts of t-butylperoxy-2-ethylhexanoate (polymerization initiator) with 18 parts of A Solvent. The monomer mixture and initiator mixture were added dropwise to the reaction vessel over a period of 3 hours. After reaction by a standard method, the resin solids content was adjusted to 65% with A Solvent. In this way, an amino group-containing acrylic resin (a1) Ac1 was obtained.

[0140] Details of the monomers in Table 1 are as follows: DMAEMA: N,N-dimethylaminoethyl methacrylate MMA: Methyl methacrylate NBA: normal butyl methacrylate IBMA: Isobutyl methacrylate EHA: 2-Ethylhexyl acrylate

[0141] [Table 1]

[0142] [Synthesis example of polyepoxide (b1) Ep2] A reaction vessel equipped with a thermometer, thermostat, stirrer, reflux condenser, and dropping device was charged with 94 parts of solvent A, and the temperature was raised to 130°C under stirring while nitrogen gas was passed through. Separately, a monomer mixture was prepared by mixing the raw material monomers shown in Table 2. An initiator mixture was also prepared by mixing 6.16 parts of t-butylperoxy-2-ethylhexanoate with 7 parts of solvent A. The monomer mixture and initiator mixture were added dropwise to the reaction vessel over a period of 3 hours. After reaction by a standard method, the solid content was adjusted to 50% with solvent A. In this way, polyepoxide (b1) Ep2 was obtained.

[0143] The details of the monomers in Table 2 are as follows: EMA: Ethyl methacrylate HEMA: Hydroxyethyl methacrylate EHMA: 2-Ethylhexyl methacrylate GMA: Glycidyl methacrylate NBA: n-butyl acrylate

[0144] [Table 2]

[0145] [Synthesis example of siloxane oligomer (a2) S1] A silane compound shown in Table 2 and 10 parts of methanol were added to a reaction vessel equipped with a thermometer, thermostat, stirrer, reflux condenser, and dropping device and mixed. A mixture of ion-exchanged water (as shown in Table 2) and 0.78 parts of sulfuric acid was then added dropwise to the reaction vessel over one hour while the temperature was raised to 65°C. The reaction was carried out for 4.5 hours while maintaining the temperature at 65°C. After the reaction was completed, the solvent was removed under reduced pressure (100 Torr) to obtain siloxane oligomer (a2)S1.

[0146] m+n was calculated from the weight average molecular weight Mw of the siloxane oligomer (a2) and the amounts of the silane compounds 1 to 4 charged.

[0147] Details of the silane compounds in Table 2 are as follows: Silane compound 1: Methyltrimethoxysilane Silane compound 2: dimethyldimethoxysilane Silane compound 3: Phenyltrimethoxysilane Silane compound 4: Diphenyldimethoxysilane

[0148] [Table 3]

[0149] [Example 1] (1) Preparation of the main agent Half of 31.11 parts of amino group-containing acrylic resin (a1) Ac1, 32.06 parts of titanium oxide (product name: CR-95, Ishihara Sangyo Kaisha, Ltd., pigment), and 18.51 parts of A solvent were placed in a tin container and stirred for approximately 30 minutes. The contents were transferred to a dispersion vessel, and an appropriate amount of glass beads were added. The mixture was then mixed in a sand mill at 2000 rpm for approximately 1 hour. After removing the glass beads, the remaining amount of amino group-containing acrylic resin (a1) Ac1 and 10.65 parts of siloxane oligomer (a2) S1 were added to the resulting white dispersion paste and mixed for 15 minutes. In this way, the base resin was obtained.

[0150] (2) Preparation of hardener 0.47 parts of polyepoxide (b1) Ep1 (trade name: Epolite 70P, Kyoeisha Chemical Co., Ltd., glycidyl ether type, epoxy equivalent 142, weight average molecular weight 284, ratio R2: 0%), 0.03 parts each of titanium tetraisopropoxide and aluminum ethoxide (curing catalyst (b2)), and 2.16 parts of solvent A were charged into a tin container and mixed for about 15 minutes using a disperser. In this way, a curing agent was obtained.

[0151] [Examples 2-4, 6-21, Comparative Examples 3 and 4] The main agent and the curing agent were obtained in the same manner as in Example 1, except that the blending amounts of each component were changed as shown in Tables 4 to 6.

[0152] [Example 5] Except for not blending titanium oxide, the base resin and curing agent were obtained in the same manner as in Example 5. In preparing the base resin, 31.11 parts of amino group-containing acrylic resin (a1) Ac1, 10.65 parts of siloxane oligomer (a2) S1, and 18.51 parts of Solvent A were placed in a tin container and stirred for about 30 minutes.

[0153] [Comparative Example 1] A base resin and a curing agent were prepared in the same manner as in Example 1, except that the curing catalyst (b2) was not added, and a coating material was obtained.

[0154] Comparative Example 2 A base resin and a curing agent were prepared in the same manner as in Example 5, except that the curing catalyst (b2) was not added, and a coating material was obtained.

[0155] [evaluation] The obtained base resin and curing agent were mixed together to obtain a paint, which was then used to prepare test panels, which were then evaluated as follows. The evaluation results are shown in Tables 4 to 6.

[0156] (i) Gloss retention after outdoor exposure test (Preparation of test plates) The paint was applied to an aluminum-treated plate (A1050P Alodine #1200, 150 mm x 70 mm x 0.8 mm) with a doctor blade (coating thickness 10 mil), and then cured for 7 days under conditions of 23°C and 50% RH to obtain a test plate.

[0157] The initial 60-degree specular gloss of the coating films using the paints of the Examples and Comparative Examples, measured in accordance with JIS K5600-4-7, was 70 to 85.

[0158] (i) Gloss retention after outdoor exposure test The test panels were placed on Miyakojima Island facing south (equatorial plane) at an angle of 20° to the horizontal for one and a half years in accordance with JIS K5600-7-6. After that, the gloss retention of the coating was evaluated in accordance with JIS K5659 7.21.

[0159] (ii) Microcrack suppression after outdoor exposure tests After the outdoor exposure test, the surface of the coating film on the test plate was visually observed and evaluated according to the following criteria. Good: No microcracks are observed Poor: Microcracks are observed

[0160] (iii) Surface dryness (Preparation of test plates) The paint was applied to a glass plate using a 3-mil doctor blade and cured for a predetermined period of time under conditions of 5°C and 80% RH to prepare a test plate.

[0161] (Touch test) The obtained test plates were subjected to a touch evaluation. Best: No finger marks left on the coating after 2 hours of curing. Good: After 8 hours of curing, no finger marks remained on the coating. Poor: Finger marks remained on the coating even after 8 hours of curing.

[0162] (iv) Pot life (When sealed) 100g of the paint was placed in a 200ml stainless steel container, which was then covered and left to stand for 5 hours at 23°C and 50% RH to prepare a sample. The condition of the sample was evaluated according to the following criteria. Good: There is almost no change in viscosity and no film forms on the surface. Poor: Little change in viscosity, film on the surface Worst: Viscosity has increased significantly and the entire paint has solidified

[0163] (If it was open) The paint was placed in a 100g, 200ml stainless steel container, left uncovered at 23°C and 50% RH to create a sample. In this case, the sample was affected by the moisture present in the air. The condition of the sample was evaluated as follows: Best: No skin after 5+ hours Good: A film forms in 2.5 to 5 hours Poor: A film forms in less than 2.5 hours Worst: The entire paint hardens in less than 2.5 hours

[0164] [Table 4]

[0165] [Table 5]

[0166] [Table 6]

[0167] All of the coating films of Examples 1-21 had high surface drying properties and long pot lives. Because the curing catalyst (b2) in Example 1-17 was used in an appropriate amount, it is believed that the first polymer portion and the second polymer portion were able to cure at appropriate rates, ensuring the necessary pot life and allowing the surface to cure at a sufficient rate. Furthermore, all of the coating films of Examples 1-21 showed suppressed cracking in outdoor exposure tests. This is believed to be because the coating had excellent curing properties, as evidenced by the coating film gloss retention rate of 80% or more after the outdoor exposure test, and therefore both the first polymer and the second polymer were sufficiently cured, allowing the functions of both the first polymer and the second polymer to be fully exerted.

[0168] The coating films of Comparative Example 1-2 all had poor surface drying properties. It is believed that the absence of curing catalyst (b2) prevented the first polymer from reacting, and the second polymer cured too slowly, preventing it from drying. Furthermore, the gloss retention rate decreased in outdoor exposure tests. This is believed to be due to the rapid deterioration of the organic components caused by insufficient curing of both the first and second polymers.

[0169] The coating film of Comparative Example 3 cracked during outdoor exposure testing. This is thought to be because the proportion of first reactive groups in polyepoxide (b1) Ep2 was high, which reacted with the siloxane oligomer (a2), preventing the flexibility provided by the organic components. The pot life was also short. This is thought to be because, as mentioned above, polyepoxide (b1) Ep2 reacted with the siloxane oligomer (a2), and because an excessive amount of curing catalyst was added, which resulted in an excessively fast curing rate.

[0170] The coating film of Comparative Example 4 showed cracks during outdoor exposure testing. This is thought to be because the addition of an excessive amount of curing catalyst caused the curing speed of both the first polymer and the second polymer to become too fast, reducing their compatibility and causing partial deterioration of the coating film. The pot life was also short. This is thought to be because, as mentioned above, the curing speed of both the first polymer and the second polymer became too fast.

[0171] The present invention includes the following aspects. [1] Contains a base agent (A) and a curing agent (B), The main component (A) contains an amino group-containing acrylic resin (a1) and a siloxane oligomer (a2), the curing agent (B) contains a polyepoxide (b1) and a curing catalyst (b2), the amino group-containing acrylic resin (a1) has an amine value of 10 mgKOH / g or more and 88 mgKOH / g or less, the polyepoxide (b1) has an epoxy equivalent of 100 g / eq or more and 1,500 g / eq or less, the amino group-containing acrylic resin (a1) does not have any reactive groups capable of reacting with silanol groups, or the number of such reactive groups is less than 11% of the number of amino groups in the amino group-containing acrylic resin (a1); In the polyepoxide (b1), there is no reactive group capable of reacting with a silanol group, or the number of the reactive groups is less than 10% of the number of epoxy groups in the polyepoxide (b1). The siloxane oligomer (a2) is represented by the following general formula (x): [ka] (In the formula, R 3 represents independently in each structural unit a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a single bond, R 4 represents, independently in each structural unit, an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 15 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a divalent oxygen atom; m is an integer from 0 to 200. and a structural unit X represented by the following general formula (y): [ka] (In the formula, R 5 and R 6 each independently in each repeating unit represents an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms; n is an integer from 0 to 200. and a structural unit Y represented by has, as a terminal group, at least one selected from the group consisting of a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms; m+n is 2 to 200; the curing catalyst (b2) comprises an organometallic compound, a resin composition for paint, wherein the mass ratio of the organometallic compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass % or more and 30 mass % or less; A coating film formed from the coating resin composition is subjected to an outdoor exposure test in accordance with JIS K5600-7-6 in Miyakojima, facing the equatorial plane at an angle of 20° to the horizontal, for one and a half years, after which the gloss retention rate in accordance with JIS K5659 7.21 is 80% or more. [2] The resin composition for coating according to [1] above, wherein the organometallic compound comprises at least one selected from the group consisting of alkoxide compounds, chelate compounds and acylate compounds of metals having a coordination number of 2 to 8. [3] The resin composition for paint according to [2] above, wherein the metal having a coordination number of 2 to 8 includes at least one selected from the group consisting of titanium, tin, zinc, aluminum, nickel, iron and zirconium. [4] The resin composition for coating according to any one of the above [1] to [3], wherein the curing catalyst (b2) comprises at least one selected from the group consisting of organotitanium compounds, organozirconium compounds and organoaluminum compounds. [5] The organotitanium compound is The following general formula (C t1 ): Ti(OR t1 )4(C t1 ) (In the formula, OR t1 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearoxy group, an isostearic acid group, or an acetylacetonate group), The following general formula (C t2 ): Ti(OR t2 ) mt (L t1 ) 4-mt (C t2 ) (In the formula, OR t2 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearoxy group, an isostearic acid group, or an acetylacetonate group, L t1each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group, mt is an integer from 1 to 3, and The following general formula (C t3 ): Ti(L t2 )4(C t3 ) (In the formula, L t2 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group. The resin composition for paint according to [4] above, which contains at least one compound selected from the group consisting of compounds represented by the following formula: [6] The organic zirconium compound is The following general formula (C z1 ): Zr(OR z1 )4(Cz1) (In the formula, OR z1 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearic acid group, or an octylic acid group), The following general formula (C z2 ): Zr(OR z2 ) mz (L z1 ) 4-mz (C z2 ) (In the formula, OR z2 each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearic acid group, or an octylic acid group, L z1each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group, mz is an integer from 1 to 3, and The following general formula (C z3 ): Zr(L z2 )4(C z3 ) (In the formula, L z2 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group. The resin composition for paint according to [4] above, which contains at least one compound selected from the group consisting of compounds represented by the following formula: [7] The organoaluminum compound is The following general formula (C a1 ): Al(OR a1 )3 (In the formula, OR a1 each independently represents an alkoxy group having 1 to 4 carbon atoms), The following general formula (C a2 ): Al(OR a2 ) ma (L a1 ) 3-ma (C a2 ) (In the formula, OR a2 each independently represents an alkoxy group having 1 to 4 carbon atoms, L a1 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, a proponylacetonato group, or a stearylacetonato group, ma is an integer from 1 to 3, and The following general formula (C a3 ): Al(L a2 )3(C a3 ) (In the formula, L a2 each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, a proponylacetonato group, or a stearylacetonato group. The resin composition for paint according to [4] or [5] above, which comprises at least one compound selected from the group consisting of compounds represented by the following formula: [8] The resin composition for coating according to any one of the above [1] to [7], wherein the curing catalyst (b2) comprises at least one selected from the group consisting of organic titanium compounds and organic zirconium compounds, and an organic aluminum compound. [9] the curing catalyst (b2) comprises an organotitanium compound and an organoaluminum compound, a mass ratio of the organotitanium compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass% or more and 12 mass% or less; The resin composition for paint of any one of the above [1] to [8], wherein the mass ratio of the organoaluminum compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2) and the polyepoxide (b1) is 0.1 mass % or more and 20 mass % or less.

[10] the curing catalyst (b2) comprises an organozirconium compound and an organoaluminum compound, a mass ratio of the organic zirconium compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass% or more and 12 mass% or less; The resin composition for paint of any one of the above [1] to [8], wherein the mass ratio of the organoaluminum compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2) and the polyepoxide (b1) is 0.1 mass % or more and 20 mass % or less.

[11] The resin composition for coating according to any one of the above [1] to

[10] , wherein the reactive group is at least one selected from the group consisting of a hydroxyl group, an alkoxy group, an alkoxysilyl group and a silanol group.

[12] A paint comprising the paint resin composition according to any one of [1] to

[11] above.

[13] Furthermore, the paint described above in

[12] contains a third-class organic solvent as defined in the Industrial Safety and Health Act.

[14] The coating material is formed from any one of the resin compositions [1] to

[11] above, a first polymer portion formed by a reaction product of the amino group-containing acrylic resin (a1) and the polyepoxide (b1); a second polymer portion formed by a polymer of the siloxane oligomer (a2) polymerized in the presence of the curing catalyst (b2) containing the organometallic compound, and independent of the first polymer portion; at least a portion of the first polymer portion and at least a portion of the second polymer portion are entangled; The second polymer portion comprises a metal from the organometallic compound. [Industrial Applicability]

[0172] The coating material according to the present invention provides a coating film that is less susceptible to cracking in outdoor environments, and is suitable for use on substrates that are primarily used or installed outdoors.

Claims

1. Contains a base agent (A) and a curing agent (B), The main component (A) contains an amino group-containing acrylic resin (a1) and a siloxane oligomer (a2), The curing agent (B) contains a polyepoxide (b1) and a curing catalyst (b2), the amino group-containing acrylic resin (a1) has an amine value of 10 mgKOH / g or more and 88 mgKOH / g or less, the polyepoxide (b1) has an epoxy equivalent of 100 g / eq or more and 1,500 g / eq or less, the amino group-containing acrylic resin (a1) does not have any reactive groups capable of reacting with silanol groups, or the number of such reactive groups is less than 11% of the number of amino groups in the amino group-containing acrylic resin (a1); In the polyepoxide (b1), there is no reactive group capable of reacting with a silanol group, or the number of the reactive groups is less than 10% of the number of epoxy groups in the polyepoxide (b1); The siloxane oligomer (a2) is represented by the following general formula (x): 【Chemical 1】 (In the formula, R ３ represents independently in each structural unit a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a single bond, R ４ represents, independently in each structural unit, an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aralkyl group having 7 to 15 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or a divalent oxygen atom; m is an integer from 0 to 200. and a structural unit X represented by the following general formula (y): 【Chemistry 2】 (In the formula, R ５ and R ６ each independently in each repeating unit represents an alkyl group having 1 to 5 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aralkyl group having 7 to 15 carbon atoms; n is an integer from 0 to 200. A structural unit Y represented by has, as a terminal group, at least one selected from the group consisting of a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms; m+n is 2 to 200; the curing catalyst (b2) contains an organometallic compound, the reactive group is at least one selected from the group consisting of a hydroxyl group, an alkoxy group, an alkoxysilyl group, and a silanol group; a resin composition for paint, wherein a mass ratio of the organometallic compound to a total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass % or more and 30 mass % or less; the composition does not contain a third compound containing both the reactive group and a third reactive group, which is at least one of an epoxy group and a halogen group, in one molecule, or contains the third compound in an amount of 1 mass % or less based on the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1); A coating film formed from the coating resin composition is subjected to an outdoor exposure test in accordance with JIS K5600-7-6 in Miyakojima, Japan, for one and a half years, with the coating facing the equator at an angle of 20° to the horizontal, and the gloss retention rate in accordance with JIS K5659 7.21 is 80% or more.

2. 2. The paint resin composition according to claim 1, wherein the organometallic compound comprises at least one selected from the group consisting of an alkoxide compound, a chelate compound, and an acylate compound of a metal having a coordination number of 2 to 8.

3. 3. The resin composition for paint according to claim 2, wherein the metal having a coordination number of 2 to 8 includes at least one selected from the group consisting of titanium, tin, zinc, aluminum, nickel, iron, and zirconium.

4. 3. The resin composition for paint according to claim 1, wherein the curing catalyst (b2) comprises at least one selected from the group consisting of organotitanium compounds, organozirconium compounds, and organoaluminum compounds.

5. The organotitanium compound is The following general formula (C ｔ１ ): Ti(OR ｔ１ ) ４ (C ｔ１ ) (In the formula, OR ｔ１ each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearoxy group, an isostearic acid group, or an acetylacetonate group. The following general formula (C ｔ２ ): Ti(OR ｔ２ ) ｍｔ (L ｔ１ ) ４－ｍｔ (C ｔ２ ) (In the formula, OR ｔ２ each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearoxy group, an isostearic acid group, or an acetylacetonate group, L ｔ１ each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group, mt is an integer from 1 to 3; and The following general formula (C ｔ３ ): Ti(L ｔ２ ) ４ (C ｔ３ ) (In the formula, L ｔ２ each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group.

5. The resin composition for paint according to claim 4, comprising at least one compound selected from the group consisting of compounds represented by the following formula:

6. The organic zirconium compound is The following general formula (C ｚ１ ): Zr(OR ｚ１ ) ４ (Cz1) (In the formula, OR ｚ１ each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearic acid group, or an octylic acid group. The following general formula (C ｚ２ ): Zr(OR ｚ２ ) ｍｚ (L ｚ１ ) ４－ｍｚ (C ｚ２ ) (In the formula, OR ｚ２ each independently represents an alkoxy group having 2 to 4 carbon atoms, a 2-ethylhexoxy group, a stearic acid group, or an octylic acid group, L ｚ１ each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group, mz is an integer from 1 to 3; and The following general formula (C ｚ３ ): Zr(L ｚ２ ) ４ (C ｚ３ ) (In the formula, L ｚ２ each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, or a proponylacetonato group.

5. The resin composition for paint according to claim 4, comprising at least one compound selected from the group consisting of compounds represented by the following formula:

7. The organoaluminum compound is The following general formula (C ａ１ ): Al(OR ａ１ ) ３ (In the formula, OR ａ１ each independently represents an alkoxy group having 1 to 4 carbon atoms. The following general formula (C ａ２ ): Al(OR ａ２ ) ｍａ (L ａ１ ) ３－ｍａ (C ａ２ ) (In the formula, OR ａ２ each independently represents an alkoxy group having 1 to 4 carbon atoms, L ａ１ each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, a proponylacetonato group, or a stearylacetonato group, ma is an integer from 1 to 3; and The following general formula (C ａ３ ): <h2 style=";text-align:left;direction:ltr">Al(L<h2 style=";text-align:left;direction:ltr"> ａ２ <h2 style=";text-align:left;direction:ltr"> )<h2 style=";text-align:left;direction:ltr"> ３ <h2 style=";text-align:left;direction:ltr"> (C<h2 style=";text-align:left;direction:ltr"> ａ３ <h2 style=";text-align:left;direction:ltr"> ) (In the formula, L ａ２ each independently represents an acetylacetonato group, an ethylacetonato group, a propylacetonato group, an isopropylacetonato group, a butylacetonato group, a propionylacetonato group, a proponylacetonato group, or a stearylacetonato group.

5. The resin composition for paint according to claim 4, comprising at least one compound selected from the group consisting of compounds represented by the following formula:

8. 3. The resin composition for paint according to claim 1, wherein the curing catalyst (b2) comprises at least one selected from the group consisting of organotitanium compounds and organozirconium compounds, and an organoaluminum compound.

9. the curing catalyst (b2) contains an organotitanium compound and an organoaluminum compound, a mass ratio of the organotitanium compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass% or more and 12 mass% or less; 3. The paint resin composition according to claim 1, wherein the mass ratio of the organoaluminum compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass % or more and 20 mass % or less.

10. the curing catalyst (b2) comprises an organozirconium compound and an organoaluminum compound, a mass ratio of the organozirconium compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass% or more and 12 mass% or less; 3. The paint resin composition according to claim 1, wherein the mass ratio of the organoaluminum compound to the total solid content of the amino group-containing acrylic resin (a1), the siloxane oligomer (a2), and the polyepoxide (b1) is 0.1 mass % or more and 20 mass % or less.

11. A paint comprising the resin composition for paint according to claim 1 or 2.

12. The paint according to claim 11, further comprising a third-class organic solvent as defined in the Industrial Safety and Health Act.

13. It is formed from the resin composition for paint of claim 1, a first polymer portion formed by a reaction product of the amino group-containing acrylic resin (a1) and the polyepoxide (b1); a second polymer portion formed by a polymer of the siloxane oligomer (a2) polymerized in the presence of the curing catalyst (b2) containing the organometallic compound, and independent of the first polymer portion; at least a portion of the first polymer portion and at least a portion of the second polymer portion are entangled; The second polymer portion comprises a metal from the organometallic compound.

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