Coating composition and coating film

Abstract

To provide a coating composition which suppresses increase in viscosity by reducing the blending amount of a matting agent even in a coating material having a high solid content concentration of 70% or more, efficiently has an excellent matte appearance and has good elongation at a low temperature of approximately -20°C when formed into a coating film.SOLUTION: There is provided a coating composition comprising a main agent and a polyisocyanate composition (C), wherein the main agent contains one or both of an aspartic acid ester compound (A-1) and / or a hydroxyl group-containing resin compound (A-2) and a matting agent (B), the content ratio of the matting agent (B) to the total amount of the aspartic acid ester compound (A-1), the hydroxyl group-containing resin compound (A-2) and the polyisocyanate composition (C) is 1 wt.% or more and 40 wt.% or less and the coating composition has a high solid content concentration of 70 wt.% or more.SELECTED DRAWING: None

Description

[Technical field]

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

[0002] In recent years, with the times such as the SDGs, companies are being asked to take environmentally friendly actions, and various efforts are being made in the field of coating materials and paints. One example is technology that reduces the amount of volatile organic solvents (VOCs) emitted during the coating film curing and drying processes by increasing the solids concentration of the paint, thereby reducing the environmental impact. In addition to reducing the environmental impact, there is also a demand to not impair the strength and durability of the resulting coating film, and even to improve the strength and durability of the coating film.

[0003] Aspartic acid ester compounds have a lower viscosity than polyol, the main component of polyurethane coating compositions, when used alone, and can significantly reduce the amount of dilution solvent in the polyaspartic coating composition, making it possible to prepare high-solids or solvent-free formulations.

[0004] In addition, since the amino group of the aspartic acid ester compound reacts quickly with the isocyanate group of either or both of the aliphatic and alicyclic polyisocyanates, polyaspartic coating compositions have the characteristics of a faster curing rate even at room temperature and excellent mechanical strength compared to polyurethane coating compositions, and are therefore expected to have many applications.

[0005] For example, Patent Document 1 discloses a polyaspartic paint composition containing a polyaspartic acid ester compound and a polyisocyanate composition in which the contents (mol %) of isocyanurate groups, iminooxadiazinedione groups, uretdione groups, allophanate groups, and biuret groups are in a specified relationship. In this polyaspartic paint composition, the polyisocyanate composition has a low viscosity suitable for high solid formulations and solventless formulations, and while maintaining curability and drying properties, the coating film using this polyaspartic paint composition is characterized by excellent chemical resistance, hardness, and weather resistance. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2018 / 163953 Summary of the Invention [Problem to be solved by the invention]

[0007] However, although the polyaspartic coating composition disclosed in Patent Document 1 achieves high solidity, no mention is made of a method for imparting a matte appearance that would enable use in the exterior field.

[0008] Silica (silicon dioxide) is generally used as a matting agent in paints. When paints containing silica are diluted with a solvent, the hydrogen bonds between the silica particles are weakened, and the viscosity can be controlled to a range suitable for coating. On the other hand, high-solids and solvent-free paints have a low solvent content, so the silica content is relatively high and the hydrogen bonds between the silica particles are strong, resulting in high viscosity paints that are not suitable for coating and poor appearance of the coating film.

[0009] The optimum range of coating viscosity differs depending on the performance of various coating machines, but for paints containing matting agents such as silica, the optimum viscosity range during coating is said to be a maximum of 20,000 mPa·s or less from the viewpoint of improving coating suitability and coating appearance, but as the silica content increases, the viscosity tends to increase, making viscosity control difficult. Also, coatings containing a large amount of matting agents tend to have poor elongation at low temperatures of around -20°C, which was known to lead to deterioration over time such as poor weather resistance.

[0010] The present invention has been made in consideration of the above circumstances, and aims to provide a coating composition that has an excellent matting effect per blend amount of matting agent, and accordingly does not easily increase in viscosity even in a coating having a high solid content concentration of 70% by weight or more. Another aim is to provide a coating film that has good elongation at a low temperature of about -20°C.

[0011] Another object of the present invention is to provide a paint base agent that has a high solids concentration of 70% by weight or more, which is capable of providing a paint composition that is inhibited from increasing in viscosity and has an excellent matte appearance, and to provide a paint composition, a coating film, a paint curing agent, and a method for imparting a matte appearance to a cured product of a paint composition that uses the same. [Means for solving the problem]

[0012] That is, the present invention includes the following aspects. [1] A coating composition comprising a base agent, a matting agent (B), and a polyisocyanate composition (C), wherein the base agent comprises either one or both of an aspartic acid ester compound (A-1) and a hydroxyl group-containing resin compound (A-2), the content of the matting agent (B) relative to the total amount of the aspartic acid ester compound (A-1), the hydroxyl group-containing resin compound (A-2), and the polyisocyanate composition (C) is 1% by weight or more and 40% by weight or less, and the solid content concentration of the coating composition is 70% by weight or more, and the polyisocyanate composition (C) comprises a polyisocyanate component (C-1) derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, and a polyester polyol having an average functionality of 2 or 3 hydroxyl groups, and having a molar ratio of urethane groups / allophanate groups of 100 / 0 to 75 / 25. [2] A coating composition comprising a base agent, a matting agent (B), and a polyisocyanate composition (C), wherein the base agent comprises either one or both of an aspartic acid ester compound (A-1) and a hydroxyl group-containing resin compound (A-2), the content of the matting agent (B) relative to the total amount of the aspartic acid ester compound (A-1), the hydroxyl group-containing resin compound (A-2), and the polyisocyanate composition (C) is 1% by weight or more and 40% by weight or less, and the solid content concentration of the coating composition is 70. % or more by weight, the polyisocyanate composition (C) comprising one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, a polyester polyol having an average functionality of 2 or 3 hydroxyl groups, and a polyoxyalkylene polyol having an average functionality of 2 to 4 hydroxyl groups, and a polyisocyanate component (C-2) having a molar ratio of urethane groups / allophanate groups of 100 / 0 to 75 / 25. [3] The coating composition according to [1] or [2], wherein the matting agent (B) is at least one selected from the group consisting of inorganic fine particles (B-1), organic polymer fine particles (B-2), organic polymer hollow particles (B-3), and wax particles (B-4). [4] The coating composition according to any one of [1] to [3], wherein the polyisocyanate composition (C) further contains a polyisocyanate component (C-3) obtained from at least one diisocyanate selected from aliphatic diisocyanates and alicyclic diisocyanates, and a monoalcohol having 1 to 20 carbon atoms, and in which the molar ratio of allophanate groups to isocyanurate groups (allophanate groups / isocyanurate groups) is 100 / 0 to 70 / 30. [5] The coating composition according to any one of [1], [3] and [4], wherein the molar ratio of urethane groups / allophanate groups in the polyisocyanate component (C-1) is 99 / 1 to 90 / 10. [6] The coating composition according to any one of [2] to [4], wherein the molar ratio of urethane groups / allophanate groups in the polyisocyanate component (C-2) is 99 / 1 to 90 / 10. [7] A coating film obtained by curing the coating composition according to any one of [1] to [6].

[0013] That is, the present invention includes the following aspects. [8] A base for a paint comprising either or both of an aspartic acid ester compound (A-1) and a hydroxyl group-containing resin compound (A-2), and organic polymer hollow particles (B-3), wherein the organic polymer hollow particles (B-3) have a true specific gravity of 0.01 or more and 0.30 or less, an average particle size of 1 μm or more and 100 μm or less, a content of 10% by weight or more and 200% by weight or less based on the total amount of either or both of the aspartic acid ester compound (A-1) and the hydroxyl group-containing resin compound (A-2), and a solids concentration of 70% by weight or more. [9] The base for a paint according to [8], wherein the organic polymer hollow particles (B-3) are hollow particles consisting of a shell made of a thermoplastic resin and a hollow portion surrounded by the shell, and particles having one or both of their surfaces further coated with a thermosetting resin.

[10] A coating composition comprising the base coating material according to [8] or [9] and a polyisocyanate composition (C1), and having a solids concentration of 70% by weight or more.

[11] A coating film obtained by curing the coating composition according to

[10] .

[12] A curing agent for a paint comprising a polyisocyanate composition (C1) and organic polymer hollow particles (B-3), wherein the organic polymer hollow particles (B-3) have a true specific gravity of 0.01 or more and 0.30 or less, an average particle size of 1 μm or more and 100 μm or less, a content of 10% by weight or more and 200% by weight or less relative to the total amount of the polyisocyanate composition (C1), and a solids concentration of 70% by weight or more.

[13] A method for imparting a matte appearance to a cured product of a coating composition comprising either or both of an aspartic acid ester compound (A-1) and a hydroxyl group-containing resin compound (A-2), and a polyisocyanate composition (C1), by adding organic polymer hollow particles (B-3) having a true specific gravity of 0.01 or more and 0.30 or less and an average particle size of 1 μm or more and 100 μm or less as a matting agent. Effect of the Invention

[0014] According to the present invention, it is possible to provide a coating composition that has an excellent matting effect per blend amount of the matting agent and, accordingly, is less likely to increase in viscosity even in a coating having a high solid content concentration of 70% by weight or more. It is also possible to provide a coating film with good elongation at a low temperature of about -20°C.

[0015] The present invention also provides a paint base having a high solids concentration of 70% by weight or more, which inhibits an increase in viscosity and can provide a paint composition having an excellent matte appearance; a paint composition, a coating film, a paint curing agent, and a method for imparting a matte appearance to a cured product of the paint composition using the same; and DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment for carrying out the present invention (hereinafter, referred to as "the present embodiment") will be described in detail. Note that the present invention is not limited to the following embodiment. The present invention can be carried out with appropriate modifications within the scope of the gist of the present invention.

[0017] <Paint composition> The present invention is a coating composition comprising a base agent, a matting agent (B), and a polyisocyanate composition (C). The base agent contains either or both of an aspartic acid ester compound (A-1) and a hydroxyl group-containing resin compound (A-2).

[0018] In one embodiment of the present invention, the polyisocyanate composition (C) contains one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, and a polyisocyanate component (C-1) derived from a polyester polyol having an average functionality of 2 or 3 hydroxyl groups and having a molar ratio of urethane groups / allophanate groups of 100 / 0 to 75 / 25.

[0019] In one embodiment of the present invention, the polyisocyanate composition (C) contains one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, a polyester polyol having an average functionality of 2 or 3 of hydroxy groups, and a polyoxyalkylene polyol having an average functionality of 2 to 4 of hydroxy groups, and a polyisocyanate component (C-2) having a molar ratio of urethane groups / allophanate groups of 100 / 0 to 75 / 25.

[0020] Next, each of the components contained in the coating composition of the present embodiment will be described in detail below.

[0021] <Main ingredient> (Aspartic acid ester compound (A-1)) The aspartic acid ester compound (A-1) used in this embodiment is an aspartic acid ester compound represented by the following formula (I). [ka] [In formula (I), X is an n-valent organic group obtained by removing a primary amino group of an n-valent polyamine, R 1 and R 2 are the same or different organic groups that are inert to isocyanate groups under reaction conditions, and n is an integer of 2 or more.

[0022] (X) In the general formula (I), X is an n-valent organic group.

[0023] The n-valent organic group may be an aliphatic group or an aromatic group. The aliphatic group may be linear, branched, or cyclic. In addition, n is an integer of 2 or more, as described later.

[0024] Examples of the linear or branched aliphatic group include an alkanediyl group (alkylene group), an alkylidene group, and an alkylidyne group. Examples of the cyclic aliphatic group include a cycloalkylene group. The aromatic group may, for example, be an arylene group such as a phenylene group.

[0025] More specifically, from the viewpoint of improving the yellowing resistance of the coating composition of this embodiment, X is preferably a linear, branched or cyclic divalent aliphatic group having from 2 to 20 carbon atoms. Examples of the linear, branched or cyclic divalent aliphatic group having from 2 to 20 carbon atoms include an n-butylene group, an n-pentylene group, an n-hexylene group, a 2,2,4-trimethylhexamethylene group, a 2,4,4-trimethylhexamethylene group, a 3,3,5-trimethyl-5-methylcyclohexylene group, a dicyclohexylmethylene group, and a 3,3'-dimethyldicyclohexylmethylene group.

[0026] (R 1 and R 2 ) In the general formula (I), R 1 and R 2 are each independently an organic group that is inert to isocyanate groups under reaction conditions. In this specification, the term "inert to isocyanate groups under reaction conditions" means that R 1 and R 2 does not have any Zerewitinoff active hydrogen-containing groups (CH acidic compounds) such as hydroxyl, amino, or thiol groups.

[0027] R 1 and R 2 are each independently preferably an alkyl group having 1 to 10 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, or a butyl group. R 1 and R 2 may be the same or different.

[0028] (n) In general formula (I), n is an integer of 2 or more. Among these, n is preferably an integer of 2 or more and 6 or less, more preferably an integer of 2 or more and 4 or less, even more preferably 2 or 3, and particularly preferably 2.

[0029] The aspartic acid ester compound represented by formula (I) can be produced by the method described in WO 2018 / 163959.

[0030] (Hydroxyl-containing resin compound (A-2)) The hydroxyl-containing resin compound (A-2) used in this embodiment may be polyester polyol, polyether polyol, acrylic polyol, polyolefin polyol, fluorine polyol, polycarbonate polyol, polyurethane polyol, etc. These hydroxyl-containing resin compounds may be contained alone or in combination of two or more. Among them, acrylic polyol or polyester polyol is preferred as the hydroxyl-containing resin compound.

[0031] The base material contains either one or both of an aspartic acid ester compound (A-1) and a hydroxyl-containing resin compound (A-2). That is, the base material may contain only the aspartic acid ester compound (A-1), may contain only the hydroxyl-containing resin compound (A-2), or may contain both the aspartic acid ester compound (A-1) and the hydroxyl-containing resin compound (A-2).

[0032] <Matte agent (B)> The matting agent (B) used in this embodiment is preferably at least one selected from the group consisting of inorganic fine particles (B-1), organic polymer fine particles (B-2), organic polymer hollow particles (B-3), and wax particles (B-4).

[0033] The content of the matting agent (B) relative to the total amount of the aspartic acid ester compound (A-1), the hydroxyl group-containing resin compound (A-2), and the polyisocyanate composition (C) is 1% by weight or more and 40% by weight or less, more preferably 5% by weight or more and 35% by weight or less, even more preferably 10% by weight or more and 30% by weight or less, and particularly preferably 10% by weight or more and 25% by weight or less. By having the content of the matting agent (B) within the above range, it is possible to achieve both control of the viscosity of the coating composition and coating film physical properties. The coating film physical properties are the properties of excellent matting property and elongation at a low temperature of about -20°C.

[0034] ·Inorganic fine particles (B-1) The inorganic fine particles (B-1) used in this embodiment have an average particle size of 1 μm or more and 20 μm or less. The average particle size is preferably 2 μm or more and 15 μm or less, more preferably 3 μm or more and 10 μm or less. When the average particle size is within the above range, the inorganic fine particles unevenly distributed on the coating film surface give the coating film surface an appropriate surface roughness, so that excellent matte properties can be obtained.

[0035] Examples of inorganic fine particles (B-1) include silica particles, alumina particles, titania particles, zirconia particles, zircon particles, tin oxide particles, magnesia particles, or mixtures thereof.Among them, it is particularly preferable that inorganic fine particles are silica particles from the viewpoint of matting ability, storage stability, etc.The shape of the silica particles is not particularly limited, and it can be spherical, hollow, porous, rod-like, plate-like, fibrous, or irregular.

[0036] Examples of commercially available products that can be used as the silica particles include the Sylysia series manufactured by Fuji Silysia Co., Ltd. ("Sylysia 350", "Sylysia 430", "Sylysia 435", "Sylysia 436", "Sylysia 450", etc.), the Sylohobic series ("Sylohobic 100", "Sylohobic 200", "Sylohobic 702", "Sylohobic 4004", etc.), the Sylosphere series ("Sylosphere 1504", "Sylosphere 1510", etc.), the SYLOID series manufactured by Grace Japan Co., Ltd. ("Syloid W300", "Syloid W500", etc.), and the ACEMATT series manufactured by Evonik Degussa Japan Co., Ltd. ("ACEMATT HK460", "ACEMATT HK400", "ACEMATT OK412", "ACEMATT TS10", "ACEMATT 3200", "ACEMATT 3300, ACEMATT3600, etc.), NIPGEL series (NIPGEL AZ-200, etc.), NIPSIL series (NIPSIL E-200A, NIPSIL SS-50B, NIPSIL SS-178B, etc.) manufactured by Nippon Silica Industry Co., Ltd., Mizukasil series (Mizukasil P-73, Mizukasil P-526, etc.) manufactured by Mizusawa Chemical Industries Co., Ltd., Carplex series (Carplex CS-8, etc.) manufactured by Shionogi & Co., Ltd., AEROSIL series (AEROSIL 200, AEROSIL R805, AEROSIL R972, etc.) manufactured by Nippon Aerosil Co., Ltd., and Radiolite series (Radiolite 100, Radiolite 200, Radiolite 500, Radiolite 500R, Radiolite 500RS, etc.) manufactured by Showa Chemical Industry Co., Ltd.

[0037] The inorganic fine particles (B-1) may be untreated inorganic fine particles, or may be inorganic fine particles surface-treated with organic or inorganic compounds. Among them, inorganic fine particles that have been organically treated are preferred from the viewpoint of alkali resistance, gloss stability, etc., and organically treated silica particles are particularly preferred. Examples of the treatment with organic compounds include polyethylene treatment, polyethylene wax treatment, and hydrophobic surface treatment.

[0038] Organic polymer particles (B-2) The organic polymer fine particles (B-2) used in this embodiment have an average particle size of 10 μm or more and 100 μm or less. The average particle size of the organic polymer fine particles (B-2) is preferably 10 μm or more and 90 μm or less, more preferably 15 μm or more and 70 μm or less. When the average particle size is within the above range, the organic polymer fine particles unevenly distributed on the coating film surface give the coating film surface an appropriate surface roughness, and therefore excellent matte properties can be obtained.

[0039] The organic polymer fine particles (B-2) contain at least one selected from the group consisting of, for example, styrene resin particles, acrylic resin particles, polyurethane resin particles, urea resin particles, polyester resin particles, and vinyl butyral resin particles, and preferably contain at least one selected from the group consisting of acrylic resin particles, polyurethane resin particles, and urea resin particles. By containing such particles in the organic polymer fine particles (B-2), a coating composition is provided that is less likely to increase in viscosity even in a coating material with a high solid content concentration of 70% or more and has an excellent matte appearance. In addition, the coating film obtained by curing the coating composition has good chemical resistance.

[0040] Styrene resin particles or acrylic resin particles The styrene resin particles or acrylic resin particles contain a styrene resin or an acrylic resin, and the styrene resin or the acrylic resin may be a polymer of an ethylenically unsaturated monomer.

[0041] The ethylenically unsaturated monomer may be a monomer having two or more ethylenically unsaturated bonds in one molecule. The monomer having two or more ethylenically unsaturated bonds in one molecule is not particularly limited, and may be, for example, ethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, 1,4-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, glycerol di(meth)acrylate. unsaturated monocarboxylic acid esters of polyhydric alcohols such as glycerol di(meth)acrylate, glycerol allyloxy di(meth)acrylate, 1,1,1-trishydroxymethylethane di(meth)acrylate, 1,1,1-trishydroxymethylethane tri(meth)acrylate, 1,1-trishydroxymethylpropane di(meth)acrylate, 1,1,1-trishydroxymethylpropane tri(meth)acrylate; unsaturated alcohol esters of polybasic acids such as triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl terephthalate, diallyl phthalate; and aromatic monomers substituted with two or more vinyl groups such as divinylbenzene.

[0042] Specific examples of styrene resin particles or acrylic resin particles include, but are not limited to, Eposter MA1002, Eposter MA1004, Eposter MA1006, Eposter MA1010 (manufactured by Nippon Shokubai Co., Ltd.), Tuftic FH-S005, Tuftic FH-S008, Tuftic FH-S010, Tuftic FH-S015, Tuftic FH-S020, Tuftic AR650SX, Tuftic AR650S, and Tuftic AR65. 0M, Tuftic AR650MX (manufactured by Toyobo Co., Ltd.), Techpolymer MBX-8, Techpolymer MBX-20, Techpolymer MBX-40 (manufactured by Sekisui Chemical Co., Ltd.), Chemisnow MX-80H3wT, MX-150, MX-180TA, MX-300, MX-500, MX-1000, MX-1500H, MX-2000, MX-3000 (manufactured by Soken Chemical & Engineering Co., Ltd.), Eposter MA2003 (manufactured by Nippon Shokubai Co., Ltd.), and the like.

[0043] Polyurethane resin particles The polyurethane resin particles include a urethane resin, which may be a reaction product of a polyol, a polyisocyanate, and an optional chain extender and / or a chain terminator.

[0044] The polyol may be a polymer polyol such as polyether polyol, polyester polyol, polycarbonate polyol, or glycerin polycaprolactone triol; or a low molecular weight polyol. The number average molecular weight of such a polymer polyol may be, for example, 300 to 5,000, or may be 500 to 3,000. The number of hydroxyl groups contained in the polymer polyol may be 2 to 3.

[0045] Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. Examples of the polyester polyol include polybutylene adipate, polyhexamethylene adipate, and polyneopentyl adipate. Examples of the polycarbonate polyol include polycaprolactone diol, poly-3-methylvalerolactone diol, and polyhexamethylene carbonate.

[0046] Examples of the low molecular weight polyol include aliphatic polyols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butanediol, pentanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, cyclohexanediol, hexanediol, dicyclohexanediol, dicyclohexanedimethanol, hydrogenated bisphenol A, and cyclohexanetriol; aromatic polyols such as bisphenol compounds such as bisphenol A, bisphenol F, and bisphenol AD, and ethylene oxide adducts or propylene oxide adducts of such bisphenol compounds; triols such as trimethylolpropane and trimethylolethane; and polyols having a carboxyl group such as dimethylolacetic acid, dimethylolpropionic acid, and dimethylolbutyric acid.

[0047] Examples of the chain extender include the low molecular weight polyols; and polyamine compounds such as ethylene diamine, propane diamine, butane diamine, hexamethylene diamine, cyclohexane diamine, isophorone diamine, dicyclohexylmethane diamine, bis(aminomethyl)cyclohexane, hydrazine, tolylene diamine, diethylene triamine, triethylene tetramine, and tetraethylene pentamine.

[0048] Examples of the terminal terminator include methanol, ethanol, propanol, butanol, ammonia, dibutylamine, and aminosilane.

[0049] Specific examples of polyurethane resin microparticles include, but are not limited to, crosslinked urethane beads such as Art Pearl C-1000 transparent, Art Pearl C-600 transparent, Art Pearl C-400 transparent, Art Pearl C-800, Art Pearl MM-120T, Art Pearl JB-800T, Art Pearl JB-600T, Art Pearl P-800T, and Art Pearl P-400T (manufactured by Negami Chemical Industries Co., Ltd.).

[0050] ·Urea resin particles The urea resin particles include a urea resin, which may be a reaction product of urea and an aldehyde. The urea resin particles may be in a powder form and may be produced by grinding the urea resin.

[0051] As the aldehyde component, formaldehyde, acetaldehyde, crotonaldehyde, benzaldehyde, etc. can be used. Among these, when formaldehyde is used, it is advantageous since the condensation reaction easily proceeds.

[0052] Specific examples of urethane resin fine particles include, but are not limited to, Pargopack M3, Pargopack M4, Pargopack M5 (manufactured by Huber Advanced Materials), SOOFINE JJ POWDER (manufactured by Hangzhou Seisaku Kagaku Co., Ltd.), and the like.

[0053] Polyester resin particles The polyester resin particles contain a polyester resin, and examples of such polyester resins include a reaction product of a polyol and a polycarboxylic acid. Examples of the polyol include the compounds exemplified as the low molecular weight polyol. Examples of the polycarboxylic acid include (anhydrous) succinic acid, (anhydrous) phthalic acid, isophthalic acid, terephthalic acid, adipic acid, sebacic acid, (anhydrous) hexahydrophthalic acid, (anhydrous) trimellitic acid, (anhydrous) pyromellitic acid, etc. The acid value of the polyester resin particles may be 100 mgKOH / g or less.

[0054] Polyvinyl butyral resin particles The vinyl butyral resin particles contain a polyvinyl butyral resin, and the polyvinyl butyral resin may be a reaction product of polyvinyl alcohol and butyraldehyde. The reaction of polyvinyl alcohol and butyraldehyde may be carried out under acidic conditions.

[0055] (Organic polymer hollow particles (B-3)) The organic polymer hollow particles (B-3) used in this embodiment have a true specific gravity of 0.01 or more and 0.30 or less. The true specific gravity is preferably 0.05 or more and 0.30 or less, more preferably 0.10 or more and 0.25 or less. When the true specific gravity is within the above range, the organic polymer hollow particles are unevenly distributed on the coating film surface during the coating film formation process. This allows the coating film to have a better matte property than when a normal matte agent is used.

[0056] The organic polymer hollow particles (B-3) have an average particle size of 1 μm or more and 100 μm or less. The average particle size is preferably 5 μm or more and 90 μm or less, more preferably 10 μm or more and 70 μm or less. When the average particle size is within the above range, the organic polymer hollow particles unevenly distributed on the coating film surface give the coating film surface an appropriate surface roughness, thereby obtaining excellent matte properties.

[0057] The organic polymer hollow particles (B-3) preferably include particles each having a shell made of a thermoplastic resin (b-1) and a hollow space surrounded by the shell, or particles whose surface is further coated with a thermosetting resin (b-2).

[0058] The thermoplastic resin (b-1) is not particularly limited, but is preferably a polymer of a polymerizable component that includes a monomer component having one polymerizable carbon-carbon double bond and may include a crosslinking agent having at least two polymerizable carbon-carbon double bonds. Examples of the monomer components included in the polymerizable component include nitrile monomers such as acrylonitrile, methacrylonitrile, fumaronitrile, and maleonitrile; halogenated vinyl monomers such as vinyl chloride; halogenated vinylidene monomers such as vinylidene chloride; vinyl ester monomers such as vinyl acetate, vinyl propionate, and vinyl butyrate; unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, ethacrylic acid, crotonic acid, and cinnamic acid; maleic acid, itaconic acid, fumaric acid, citraconic acid, chloromaic acid, and the like. Carboxyl group-containing monomers such as unsaturated dicarboxylic acids, anhydrides of unsaturated dicarboxylic acids, and unsaturated dicarboxylic acid monoesters, such as monomethyl maleate, monoethyl maleate, monobutyl maleate, monomethyl fumarate, monoethyl fumarate, monomethyl itaconate, monoethyl itaconate, and monobutyl itaconate; methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (meth)acrylic acid ester monomers such as butyl acrylate, stearyl (meth)acrylate, phenyl (meth)acrylate, isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, and 2-hydroxyethyl (meth)acrylate; (meth)acrylamide monomers such as acrylamide, substituted acrylamide, methacrylamide, and substituted methacrylamide; maleimide monomers such as N-phenylmaleimide and N-cyclohexylmaleimide. Examples of suitable monomers include styrene-based monomers such as styrene and α-methylstyrene; ethylenically unsaturated monoolefin-based monomers such as ethylene, propylene, and isobutylene; vinyl ether-based monomers such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether; vinyl ketone-based monomers such as vinyl methyl ketone; N-vinyl-based monomers such as N-vinylcarbazole and N-vinylpyrrolidone; vinylnaphthalene salts; and itaconate diesters such as dimethyl itaconate and dibutyl itaconate.The carboxyl group-containing monomer may have a part or all of its carboxyl groups neutralized during or after polymerization. These monomer components may be used alone or in combination of two or more.

[0059] The thermosetting resin (b-2) is not particularly limited, but is preferably at least one selected from the group consisting of, for example, melamine formaldehyde resin, phenol formaldehyde resin, urea formaldehyde resin, and epoxy resin.

[0060] The organic polymer hollow particles (B-3) may be composite hollow particles having inorganic fine powder attached to the surface.

[0061] A gap is formed in the hollow portion. The gap may contain a substance such as a gas. The gas is not particularly limited, but examples thereof include inorganic gases such as nitrogen, oxygen, and air, and organic gases such as hydrocarbons.

[0062] The organic polymer hollow particles (B-3) are not particularly limited, and examples thereof include trade names "Matsumoto Microsphere F-30E", "Matsumoto Microsphere F-50E", "Matsumoto Microsphere F-65E", "Matsumoto Microsphere FN-80SDE", "Matsumoto Microsphere F-65DE", "Matsumoto Microsphere F-80DE", "Matsumoto Microsphere F-78DE", "Matsumoto Microsphere MFL-81GTA", "Matsumoto Microsphere MFL-81CGA", "Matsumoto Microsphere MFL-HD30CA", "Matsumoto Microsphere MFL-60CA", "Matsumoto Microsphere MFL-UPR60", "Matsumoto Microsphere MFL-100MCA", and "Matsumoto Microsphere MFL-110CAL" manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.

[0063] (wax particles) The wax particles (B-4) used in this embodiment have an average particle size of 10 μm or more and 100 μm or less. The average particle size is preferably 10 μm or more and 90 μm or less, and more preferably 15 μm or more and 70 μm or less. When the average particle size is within the above range, the wax particles unevenly distributed on the coating film surface give the coating film surface an appropriate surface roughness, thereby obtaining excellent matte properties.

[0064] As the polyolefin wax, for example, polyethylene wax, modified polyethylene wax, amide modified polyethylene wax, PTFE modified polyethylene wax, polypropylene wax, modified polypropylene wax, etc. can be used.

[0065] Specific examples of the wax particles (B-4) include, but are not limited to, CERAFLOUR913, CERAFLOUR914, CERAFLOUR915, CERAFLOUR916, CERAFLOUR917, CERAFLOUR925, CERAFLOUR927, CERAFLOUR929, CERAFLOUR950, CERAFLOUR970, CERAFLOUR981R, CERAFLOUR988, CERAFLOUR991, CERAFLOUR994, CERAFLOUR996R, and CERAFLOUR997 manufactured by BYK-Chemie. R, CERAFLOUR998R, CERAFLOUR1000, MP Gokyo Food & Chemical Co., Ltd.'s PropylTex100S, PropylTex140S, PropylTex200S, PropylTex200SF, PropylTex230S, PropylTex270S, PropylTex325S, Sanyo Kasei Co., Ltd.'s Viscol 330-P, Viscol 440-P, Viscol 550-P, Viscol 660-P, Sunwax 161-P, Sunwax 131-P, Sunwax 151-P, Sunwax 171-P, Shamrock Examples of such copolymers include S-379H, S-379N8, S-394MG, S-394N1, S-394N5, S-395N2, S-395N5, S-395SP5, and S-363 manufactured by Technologies.

[0066] <Polyisocyanate composition (C)> The polyisocyanate composition (C) used in the present embodiment contains a polyisocyanate component (C-1) or (C-2) described below.

[0067] <Polyisocyanate component (C-1)> The polyisocyanate component (C-1) is derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, and a polyester polyol having an average functionality of 2 or 3 hydroxyl groups, and has a molar ratio of urethane groups / allophanate groups of 100 / 0 to 75 / 25.

[0068] <Polyisocyanate component (C-2)> The polyisocyanate component (C-2) is derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, a polyester polyol having an average functionality of 2 or 3 hydroxyl groups, and a polyoxyalkylene polyol having an average functionality of 2 to 4 hydroxyl groups, and has a molar ratio of urethane groups / allophanate groups of 100 / 0 to 75 / 25.

[0069] Examples of aliphatic diisocyanates include, but are not limited to, 1,4-diisocyanatobutane, 1,5-diisocyanatopentane (hereinafter sometimes abbreviated as "PDI"), ethyl (2,6-diisocyanato)hexanoate, 1,6-diisocyanatohexane (hereinafter sometimes abbreviated as "HDI"), 1,9-diisocyanatononane, 1,12-diisocyanatododecane, 2,2,4- or 2,4,4-trimethyl-1,6-diisocyanatohexane, etc. These aliphatic diisocyanates may be used alone or in combination of two or more.

[0070] Examples of alicyclic diisocyanates include, but are not limited to, 1,3- or 1,4-bis(isocyanatomethyl)cyclohexane (hereinafter sometimes abbreviated as "hydrogenated XDI"), 1,3- or 1,4-diisocyanatocyclohexane, 3,5,5-trimethyl-1-isocyanato-3-(isocyanatomethyl)cyclohexane (hereinafter sometimes abbreviated as "IPDI"), 4-4'-diisocyanato-dicyclohexylmethane (hereinafter sometimes abbreviated as "hydrogenated MDI"), 2,5- or 2,6-diisocyanatomethylnorbornane, etc. These alicyclic diisocyanates may be used alone or in combination of two or more.

[0071] These aliphatic diisocyanates and alicyclic diisocyanates may be used alone, or two or more of them may be used in combination.

[0072] Among these, the diisocyanate is preferably PDI, HDI, IPDI, hydrogenated XDI, or hydrogenated MDI, more preferably PDI, HDI, or IPDI, and even more preferably HDI.

[0073] In the production of polyisocyanates, in addition to the diisocyanates described above, isocyanate monomers such as those shown below may be further used. (1) Aromatic diisocyanates such as diphenylmethane-4,4'-diisocyanate (MDI), 1,5-naphthalene diisocyanate, tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), and m-tetramethylxylylene diisocyanate (TMXDI). (2) Triisocyanates such as 4-isocyanatomethyl-1,8-octamethylene diisocyanate (hereinafter sometimes referred to as "NTI"), 1,3,6-hexamethylene triisocyanate (hereinafter sometimes referred to as "HTI"), bis(2-isocyanatoethyl) 2-isocyanatoglutarate (hereinafter sometimes referred to as "GTI"), and lysine triisocyanate (hereinafter sometimes referred to as "LTI").

[0074] (Polyester polyol) The polyester polyol is a dihydric and / or trihydric polyol containing a repeating unit represented by -O(CH2)5CO-, and can be derived from a dihydric and / or trihydric alcohol and ε-caprolactone, etc. In addition, although there is no particular limitation, for example, it can be obtained by ring-opening polymerization of ε-caprolactone, etc., using a dihydric and / or trihydric alcohol as an initiator in the presence of a catalyst. In addition, polyester polyols having an average functionality of 2 and / or 3 can be obtained by a condensation reaction of a dibasic acid alone or a mixture of two or more types with a polyhydric alcohol alone or a mixture of two or more types, using a dihydric and / or trihydric alcohol as an initiator.

[0075] Examples of the dibasic acid include carboxylic acids such as succinic acid, adipic acid, dimer acid, maleic anhydride, phthalic anhydride, isophthalic acid, terephthalic acid, 1,4-cyclohexanedicarboxylic acid, succinic anhydride, maleic acid, phthalic acid, glutaric acid, suberic acid, azelaic acid, sebacic acid, decanedioic acid, itaconic acid, itaconic anhydride, hexahydrophthalic acid, hexahydrophthalic anhydride, tetrahydrophthalic acid, and tetrahydrophthalic anhydride.

[0076] Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, trimethylpentanediol, cyclohexanediol, 2-ethyl-1,3-hexanediol, trimethylolpropane, glycerin, pentaerythritol, 2-methylolpropanediol, ethoxylated trimethylolpropane, 1,3-propanediol, pentane-1,5-diol, heptane-1,7-diol, octane-1,8-diol, and nonane-1,9-diol. , decane-1,10-diol, dodecane-1,12-diol, cyclohexane-1,4-dimethanol, 4,4'-(1-methylethylidene)biscyclohexanol, 1,1,1-trimethylolethane, hexane-1,2,6-triol, dipropylene glycol, propane-1,2-diol, butane-1,3-diol, hexane-1,2-diol, 2-methylpentane-2,4-diol, 3-methylpentane-1,5-diol, octane-1,2-diol, 2-butyl-2-ethylpropane-1,3-diol, decane-1,2-diol, and the like.

[0077] The polyester polyol having an average functionality of 2 and / or 3 is preferably a polycaprolactone polyol having an average functionality of 2 and / or 3, a polyester polyol which is a condensate of a dibasic acid having an average functionality of 2 and / or 3 with a polyhydric alcohol, or a mixture thereof.

[0078] When a polyisocyanate composition using a polyester polyol having an average functionality of 2 and / or 3 is used as a curing agent and an aspartic acid ester compound is used as a base compound, the compatibility between the base compound and the curing agent is high. Therefore, the polyisocyanate composition of this embodiment can be suitably used as a curing agent for a polyaspartic paint composition having an aspartic acid ester compound as a base compound. Furthermore, when a polyester polyol having an average functionality of 2 and / or 3 is used, high flexibility is exhibited due to three-dimensional crosslinking including physical crosslinking, and a coating film with high coating elongation can be produced.

[0079] The number average molecular weight of the polyester polyol having an average functionality of 2 and / or 3 is preferably 250 to 4000. The number average molecular weight is more preferably 250 to 1500, more preferably 250 to 1000, and particularly preferably 300 to 800. When the number average molecular weight of the polyester polyol having an average functionality of 2 and / or 3 is 250 or more, a coating film having high coating elongation can be produced when used as a curing agent for a coating composition. When the number average molecular weight of the polyester polyol having an average functionality of 2 and / or 3 is 4000 or less, the coating composition is likely to maintain a low viscosity state when used as a curing agent for a coating composition. The number average molecular weight of the polyester polyol having an average functionality of 2 and / or 3 can be measured by the method described in the examples below.

[0080] The initiator may be a dihydric alcohol, such as ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, trimethylpentanediol, cyclohexanediol, pentaerythritol, 2-methylolpropanediol, 2-ethyl-1,3-hexanediol, 1,3-propanediol, pentane-1,5-diol, heptane-1,7-diol, octane-1,8-diol, or nonane-1,9-diol. , decane-1,10-diol, dodecane-1,12-diol, cyclohexane-1,4-dimethanol, dipropylene glycol, propane-1,2-diol, butane-1,3-diol, hexane-1,2-diol, 2-methylpentane-2,4-diol, 3-methylpentane-1,5-diol, octane-1,2-diol, 2-butyl-2-ethylpropane-1,3-diol, decane-1,2-diol, etc., and trihydric alcohols such as trimethylene glycol and glycerin can be used. From the viewpoint of obtaining a polyisocyanate composition with a low viscosity, a branched polyhydric alcohol is preferred.

[0081] As the catalyst, organic titanium compounds such as tetrabutyl titanate, tetrapropyl titanate, and tetraethyl titanate, and tin compounds such as tin octoate, dibutyltin oxide, dibutyltin laurate, stannous chloride, and stannous bromide are preferably used. From the viewpoint of facilitating adjustment of the content of polyester polyol having an average functionality of 2, the catalyst is preferably a tin compound.

[0082] The ring-opening polymerization of ε-caprolactone or the like is preferably carried out in a nitrogen gas atmosphere by setting the molar ratio of ε-caprolactone and the above initiator so as to obtain a predetermined molecular weight, adding 0.1 ppm to 100 ppm of a catalyst relative to ε-caprolactone, and reacting for 4 hours to 10 hours at a temperature of 150° C. to 200° C. However, it is important to control the content of caprolactone dimer at a ratio of 100 ppm to 1000 ppm at the end of the reaction. If necessary, the caprolactone dimer may be removed from the produced polycaprolactone polyol by a method such as extraction or distillation. In addition to ε-caprolactone, other cyclic lactones such as trimethylcaprolactone and valerolactone may be partially mixed.

[0083] The polyester polyol can be produced, for example, by a known condensation reaction of a dibasic acid or a mixture thereof with a polyhydric alcohol or a mixture thereof, for example, by combining a dibasic acid component and a polyhydric alcohol component and heating them at about 160 to 220°C.

[0084] Examples of commercially available bifunctional polycaprolactone polyols include those manufactured by Daicel Corporation under the trade names "Placcel 210" (number average molecular weight 1000), "Placcel 210CP" (number average molecular weight 1000), "Placcel 212" (number average molecular weight 1250), "Placcel 212CP" (number average molecular weight 1250), "Placcel 220" (number average molecular weight 2000), "Placcel 220CPB" (number average molecular weight 2000), and "Placcel 220CPT" (number average molecular weight 2000); and those manufactured by Ingevity Corporation under the trade names "Capa 2043" (number average molecular weight 400), "Capa 2054" (number average molecular weight 550), and "Capa 2085" (number average molecular weight 830).

[0085] In addition, examples of commercially available bifunctional polyester polyols that may be used include "Kuraray Polyol P-510" (number average molecular weight 500) manufactured by Kuraray Co., Ltd. and "ODX2406" (number average molecular weight 440) manufactured by DIC Corporation.

[0086] Examples of commercially available trifunctional polycaprolactone polyols include those manufactured by Daicel Corporation under the trade names "Placcel 305" (number average molecular weight 550), "Placcel 308" (number average molecular weight 850), "Placcel 309" (number average molecular weight 900), "Placcel 312" (number average molecular weight 1250), and "Placcel 320" (number average molecular weight 2000); those manufactured by DIC Corporation under the trade name "ODX2542C" (number average molecular weight 850); and those manufactured by Ingevity Corporation under the trade names "Capa3050" (number average molecular weight 540) and "Capa23091" (number average molecular weight 900).

[0087] (Polyoxyalkylene polyol) The polyoxyalkylene polyol is -O(CH2) nIt can be derived from a dihydric to tetrahydric alcohol and ethylene oxide, propylene oxide, tetrahydrofuran, etc. In addition, although there is no particular limitation, it can be obtained, for example, by cationic polymerization of ethylene oxide, propylene oxide, tetrahydrofuran, etc. with a dihydric to tetrahydric alcohol as an initiator in the presence of a catalyst.

[0088] The number average molecular weight of the polyoxyalkylene polyol is preferably 200 or more and 2,000 or less, more preferably 200 or more and 1,500 or less, and even more preferably 200 or more and 1,000 or less.

[0089] As the initiator, dihydric alcohols such as ethylene glycol, propylene glycol, 1,3-butylene glycol, neopentyl glycol, etc., trihydric alcohols such as trimethylene glycol, glycerin, etc., and tetrahydric alcohols such as pentaerythritol, etc. are used. From the viewpoint of obtaining a polyisocyanate component with a low viscosity, branched polyhydric alcohols are preferred.

[0090] As the catalyst, a hydroxide of lithium, sodium, potassium, or the like, or a strongly basic catalyst such as an alcoholate or an alkylamine can be used.

[0091] Cationic polymerization of ethylene oxide, propylene oxide, tetrahydrofuran, or the like is preferably carried out in a nitrogen gas atmosphere by setting a molar ratio of ethylene oxide, propylene oxide, tetrahydrofuran, or the like and the above-mentioned initiator so as to obtain a predetermined molecular weight, adding a catalyst of 0.1 ppm to 100 ppm relative to the ethylene oxide, propylene oxide, tetrahydrofuran, or the like, and reacting at a temperature of 150° C. to 200° C. for 4 hours to 10 hours.

[0092] Commercially available bifunctional polyoxyalkylene polyols include, for example, SK Chemicals' product names "ECOTRION H1000" (number average molecular weight 1000) and "ECOTRION H2000" (number average molecular weight 2000); Allessa's product names "Velvet H250" (number average molecular weight 227); and Mitsubishi Chemical's product name "BioPTMG650" (number average molecular weight 655).

[0093] The polyol component preferably contains two types of polyester polyols having different structures, or a polyester polyol and a polyoxyalkylene polyol. When the polyol contains the above combination of two types of polyols, crystallization can be further suppressed.

[0094] When the polyol is a combination of two polyester polyols having different structures, or a combination of a polyester polyol and a polyoxyalkylene polyol, the content of the polyester polyol is preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 35% by mass or more, based on the total mass of the polyols. By having the content of the polyester polyol be equal to or more than the above lower limit, the weather resistance of the coating film can be improved.

[0095] The polyisocyanate compositions (C-1) and (C-2) each contain a urethane group and an allophanate group in one molecule. The urethane group is formed by a reaction between an isocyanate group of a diisocyanate and a hydroxyl group of a polyol. The allophanate group is formed by a reaction between a urethane group and an isocyanate group of a diisocyanate, or by a reaction between two isocyanate groups of a diisocyanate and one hydroxyl group of a polyol.

[0096] The molar ratio of urethane group / allophanate group in the polyisocyanate compositions (C-1) and (C-2) is 100 / 0 to 75 / 25. The molar ratio of urethane group / allophanate group is preferably 100 / 0 to 80 / 20, more preferably 100 / 0 to 85 / 15, even more preferably 100 / 0 to 90 / 10, and particularly preferably 99 / 1 to 90 / 10. By being within the above range, the storage stability of the obtained polyisocyanate composition is increased, and the matte property of the obtained coating film and the elongation at a low temperature of about -20°C can be compatible within an appropriate range.

[0097] The polyisocyanate compositions (C-1) and (C-2) may contain other functional groups, such as isocyanurate groups and uretdione groups, in addition to urethane groups and allophanate groups.

[0098] Alternatively, the polyisocyanate compositions (C-1) and (C-2) of the present embodiment may further contain, in addition to a polyisocyanate having a urethane group and an allophanate group in the molecule, a polyisocyanate having one of the functional groups of a urethane group and an allophanate group, or a polyisocyanate having other functional groups, such as an isocyanurate group or a uretdione group, either alone or in combination of two or more of them.

[0099] The molar amount of each functional group in the polyisocyanate compositions (C-1) and (C-2) is, for example, 13 The molar ratio of the specific functional groups can be calculated using the calculated molar amounts of each functional group.

[0100] (Polyisocyanate component (C-3)) The polyisocyanate composition (C) used in the present embodiment may further contain a polyisocyanate component (C-3) obtained from at least one diisocyanate selected from aliphatic diisocyanates and alicyclic diisocyanates, and a monoalcohol having 1 to 20 carbon atoms, and in which the molar ratio of allophanate groups to isocyanurate groups (allophanate groups / isocyanurate groups) is 100 / 0 to 70 / 30.

[0101] The number of carbon atoms of the monoalcohol having 1 to 20 carbon atoms in the polyisocyanate component (C-3) is preferably 2 or more, more preferably 3 or more, particularly preferably 4 or more, and most preferably 6 or more. The number of carbon atoms of the monoalcohol having 1 to 20 carbon atoms is preferably 16 or less, more preferably 12 or less, particularly preferably 9 or less. One type of monoalcohol may be used, or two or more types may be mixed. The monoalcohol used in the present invention may contain an ether group, an ester group, or a carbonyl group in the molecule, but a monoalcohol consisting of a saturated hydrocarbon group is preferred. A branched monoalcohol is more preferred.

[0102] Examples of such monoalcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, 1-pentanol, 2-pentanol, isoamyl alcohol, 1-hexanol, 2-hexanol, 1-heptanol, 1-octanol, 2-ethyl-1-hexanol, 3,3,5-trimethyl-1-hexanol, tridecanol, pentadecanol, palmityl alcohol, stearyl alcohol, cyclopentanol, cyclohexanol, methylcyclohexanol, and trimethylcyclohexanol. Of these, isobutanol, n-butanol, isoamyl alcohol, 1-hexanol, 1-heptanol, 1-octanol, 2-ethyl-1-hexanol, tridecanol, pentadecanol, palmityl alcohol, stearyl alcohol, and 1,3,5-trimethylcyclohexanol are more preferred.

[0103] 1-propanol, isobutanol, 1-butanol, isoamyl alcohol, pentanol, 1-hexanol, 2-hexanol, 1-heptanol, 1-octanol, 2-octanol, 2-ethyl-hexyl alcohol, 3,3,5-trimethyl-1-hexanol are even more preferred.

[0104] 1-hexanol, 2-hexanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, 3,3,5-trimethyl-1-hexanol are most preferred.

[0105] In the polyisocyanate component (C-3), the molar ratio of allophanate groups / isocyanurate groups is 100 / 0 to 70 / 30, preferably 100 / 0 to 80 / 20. The molar ratio of allophanate groups / isocyanurate groups is preferably 99 / 1 or less, more preferably 98 / 2 or less. The molar ratio of allophanate groups / isocyanurate groups is preferably 85 / 15 or more, more preferably 90 / 10 or more, particularly preferably 95 / 5 or more. When the molar ratio of allophanate groups / isocyanurate groups is 100 / 0 to 70 / 30, the curability is sufficient.

[0106] The content of the polyisocyanate component (C-3) contained in the polyisocyanate composition (C) is preferably 0% or more and 50% or less, more preferably 0% or more and 30% or less, and even more preferably 0% or more and 20% or less. By being within the above range, crystallization can be further suppressed, and the polyisocyanate composition of this embodiment can be blended as a uniform curing agent in a coating composition, particularly a polyaspartic coating composition. This allows a coating film with excellent curability and surface appearance to be obtained.

[0107] The polyisocyanate composition (C) used in this embodiment can be produced by the method described in International Publication No. 2018 / 163959. Specifically, the polyisocyanate composition used in this embodiment can be obtained by reacting the isocyanate group of the diisocyanate monomer with a polyester polyol having an average functionality of 2 and / or 3 and / or a hydroxyl group of a polyoxyalkylene polyol having an average functionality of 2 to 4 in the presence of an excess diisocyanate monomer to form a urethane group, and then removing the unreacted diisocyanate monomer. Furthermore, an allophanate reaction may be performed after the urethane reaction or simultaneously with the urethane reaction. The allophanate reaction proceeds only by heating, but may also be performed using an allophanate reaction catalyst.

[0108] The isocyanate content (hereinafter also referred to as "NCO content") of the polyisocyanate composition (C) used in this embodiment is preferably 5% by mass or more and 30% by mass or less with respect to the total amount (100% by mass) of the polyisocyanate composition. The NCO content is more preferably 6% by mass or more, and even more preferably 7% by mass or more. The NCO content is more preferably 25% by mass or less, and even more preferably 20% by mass or less. When the NCO content is 5% by mass or more, the drying property and curing property of the coating film are more easily maintained. When the NCO content is 30% by mass or less, when used as a curing agent for a coating composition, the elongation, scratch resistance, and weather resistance of the resulting coating film at a low temperature of about -20°C are easily improved. The NCO content of the polyisocyanate composition can be measured by the method described in the examples described later.

[0109] The viscosity of the polyisocyanate composition (C) used in this embodiment at 25°C is preferably 500 mPa.s or more and 10000 mPa.s or less. The viscosity is more preferably 600 mPa.s or more, even more preferably 700 mPa.s or more, and particularly preferably 800 mPa.s or more. The viscosity is more preferably 5000 mPa.s or less, even more preferably 3000 mPa.s or less, and particularly preferably 2000 mPa.s or less. When the viscosity is 500 mPa.s or more, when used as a curing agent for a coating composition, it is easy to improve the elongation and scratch resistance of the resulting coating film at a low temperature of about -20°C. When the viscosity is 10000 mPa.s or less, it is easy to maintain the drying property. The viscosity of the polyisocyanate composition can be measured by the method described in the examples described later.

[0110] The number average molecular weight of the polyisocyanate composition (C) used in this embodiment is preferably 250 or more and 4000 or less. The number average molecular weight is more preferably 300 or more and 3000 or less, further preferably 300 or more and 2500 or less, and particularly preferably 400 or more and 2000 or less. When the number average molecular weight is 250 or more, when used as a curing agent for a coating composition, it is easy to improve the elongation, scratch resistance, and weather resistance of the resulting coating film at a low temperature of about -20 ° C. When the number average molecular weight is 4000 or less, it is easy to maintain the drying property. The number average molecular weight of the polyisocyanate composition can be measured by the method described in the examples described later.

[0111] The average number of isocyanate groups in the polyisocyanate composition (C) used in this embodiment is preferably 2.0 or more and 10.0 or less. The average number of isocyanate groups is more preferably 2.1 or more, even more preferably 2.2 or more, and particularly preferably 2.3 or more. The average number of isocyanate groups is more preferably 8.0 or less, even more preferably 6.0 or less, and particularly preferably 4.0 or less. When the average number of isocyanate groups is 2.0 or more, it is easier to maintain the drying property. When the average number of isocyanate groups is 10.0 or less, when used as a curing agent for a coating composition, it is easier to improve the elongation, scratch resistance, and weather resistance of the resulting coating film at a low temperature of about -20 ° C. The average number of isocyanate groups in the polyisocyanate composition can be measured by the method described in the examples described later.

[0112] The diisocyanate monomer mass concentration of the polyisocyanate composition (C) used in this embodiment is preferably 1.0 mass% or less, more preferably 0.5 mass% or less, even more preferably 0.3 mass% or less, and particularly preferably 0.1 mass% or less, relative to the total amount (100 mass%) of the polyisocyanate composition. When the diisocyanate monomer mass concentration is 1.0 mass% or less, drying properties are more easily maintained. The diisocyanate monomer mass concentration of the polyisocyanate composition can be measured by the method described in the examples below.

[0113] (Isocyanate group / Amino group) The molar ratio (isocyanate group / amino group) of the isocyanate group of the polyisocyanate composition (C) to the amino group of the aspartic acid ester compound (A-1) is preferably 1 / 10 or more and 10 / 1 or less, more preferably 1 / 5 or more and 5 / 1 or less, and even more preferably 1 / 2 or more and 2 / 1 or less. When the isocyanate group / amino group is 1 / 10 or more, the main agent does not become too excessive, and the elongation at a low temperature of about -20 ° C. when formed into a coating film can be made good. In addition, when the isocyanate group / amino group is within the above numerical range, the balance between the isocyanate group and the amino group is well maintained, and the concentration of the urea bond that becomes the bonding point in the coating film can be increased, and the weather resistance when formed into a coating film can be made good.

[0114] (Isocyanate group / Hydroxyl group) The molar ratio (isocyanate group / hydroxyl group) of the isocyanate group of the polyisocyanate composition (C) to the hydroxyl group of the hydroxyl group-containing resin compound (A-2) is preferably 1 / 10 or more and 10 / 1 or less, more preferably 1 / 5 or more and 5 / 1 or less, and even more preferably 1 / 2 or more and 2 / 1 or less. When the isocyanate group / hydroxyl group is 1 / 10 or more, the main agent does not become too excessive, and the elongation at a low temperature of about -20 ° C. when formed into a coating film can be made good. In addition, when the isocyanate group / hydroxyl group is within the above numerical range, the balance between the isocyanate group and the hydroxyl group is well maintained, and the concentration of the urethane bond that becomes the bonding point in the coating film can be increased, and the weather resistance when formed into a coating film can be made good.

[0115] (Other ingredients) The coating composition of the present embodiment may further contain other main components such as melamine resin, epoxy resin, polyurethane resin, etc., as necessary. In addition, when the above-mentioned hydroxyl group-containing (aqueous) resin compound has a carboxy group, an oxazoline group-containing compound and a carbodiimide group-containing compound may be blended. In addition, when the above-mentioned hydroxyl group-containing (aqueous) resin compound has a carbonyl group, a hydrazide group-containing compound and a semicarbazide group-containing compound may be blended. These compounds may be blended alone or in combination of two or more.

[0116] Since the coating composition of the present embodiment has a superior appearance when formed into a coating film, known components may be added as appropriate as compounding agents for coating compositions. Examples of such components include solvents, surfactants, photosensitizers, foam stabilizers, foaming agents (foaming agents), foaming assistants, foam stabilizers, foam inhibitors (foam suppressors, foam breakers), emulsifiers, pigment dispersants, lubricants, propellants, thickeners, curing agents, polymerization initiators, pigments, plasticizers, adhesives, fillers, antifouling agents, rust inhibitors, slip agents, driers, stabilizers, ultraviolet absorbers, antibacterial or antifungal agents, and flame retardants.

[0117] <Method of producing coating composition> The coating composition of this embodiment is obtained by adding the matting agent (B) to either one or both of the above-mentioned aspartic acid ester compound (A-1) and hydroxyl group-containing resin compound (A-2) while mixing, and then mixing other components as necessary to obtain a main component (MC), and then blending the above-mentioned polyisocyanate composition (C), which is a curing agent component, into the main component (MC) and mixing using a known method. At this time, a solvent may or may not be used. The coating composition of this embodiment has a lower viscosity than conventional ones, so it can be produced while maintaining workability even in a high solid formulation.

[0118] <Application> The coating composition of the present embodiment is suitably used as a primer, intermediate coat or top coat on metals such as steel plates and surface-treated steel plates, plastics, ceramics such as inorganic materials, glass and concrete by roll coating, curtain flow coating, spray coating, electrostatic coating, bell coating, immersion, roller coating, brush coating or the like.

[0119] The coating composition of the present embodiment is suitably used to impart cosmetic properties, weather resistance, acid resistance, rust prevention, chipping resistance, adhesion, etc. to pre-coated metals including rust-resistant steel plates, painted parts of automobiles, painted parts of plastics, etc. The coating composition of the present embodiment is also useful as an adhesive, pressure-sensitive adhesive, elastomer, foam, surface treatment agent, etc.

[0120] In addition, the coating composition of the present embodiment has a flexible coating film and an increased crosslinking density, and is particularly excellent in weather resistance. Therefore, the coating composition of the present embodiment is suitably used for heavy-duty anticorrosion coating of structures that require long-term weather resistance, such as bridges, highways, transmission towers, and wind power generation facilities (towers, blades, etc.), which are exposed to severe environments such as wind, rain, snow, and temperature changes.

[0121] <Coating film> The coating film of this embodiment is a coating film formed by curing the above-mentioned coating composition. The coating film of the present embodiment has an excellent matte appearance and good chemical resistance. The coating film of the present embodiment is obtained by applying the above-mentioned coating composition using a known method such as roll coating, curtain flow coating, spray coating, bell coating, electrostatic coating, etc., and then drying or baking at room temperature to harden the coating film.

[0122] <Base material for paint> The present embodiment relates to a base material for a coating material, which contains either or both of an aspartic acid ester compound (A-1) and a hydroxyl group-containing resin compound (A-2), and organic polymer hollow particles (B-3). Hereinafter, "either or both of the aspartic acid ester compound (A-1) and the hydroxyl group-containing resin compound (A-2)" may be referred to as "main component". Hereinafter, each component constituting the base paint of the present embodiment will be described.

[0123] <Main ingredient> The explanation regarding the main component is the same as that described above in (Aspartic acid ester compound (A-1)) and (Hydroxyl group-containing resin compound (A-2)).

[0124] <Organic polymer hollow particles (B-3)> The explanation regarding the organic polymer hollow particles (B-3) contained in the base paint is the same as that described above in (Organic polymer hollow particles (B-3)).

[0125] In the base material for paint of this embodiment, the content of the organic polymer hollow particles (B-3) relative to the total amount of the base material components is 10% by weight or more and 200% by weight or less, preferably 15% by weight or more and 150% by weight or less, and more preferably 25% by weight or more and 130% by weight or less. By the content being within the above range, the viscosity of the obtained paint and the matte property of the coating film can be compatible within an appropriate range.

[0126] The base paint composition of this embodiment has a solids concentration of 70% by weight or more. When the solid content is 70% by weight or more, it is possible to achieve both an excellent matte appearance and suppression of an increase in the viscosity of the paint. In addition, when the paint composition containing the paint base is formed into a coating film, the appearance and chemical resistance are good.

[0127] <Paint composition 2> The coating composition 2 according to one embodiment of the present invention contains the above-mentioned base material for coating and a polyisocyanate composition (C1). The solid content of the coating composition 2 is 70% by weight or more.

[0128] <Polyisocyanate composition (C1)> The polyisocyanate composition (C1) used in the present embodiment may be a polyisocyanate component obtained from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, and a polyester polyol having an average functionality of 2 and / or 3. The polyisocyanate composition (C1) may be a polyisocyanate component that can be produced at once in the presence of an excess diisocyanate monomer by a known method using one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates as raw materials, by carrying out one or more reactions selected from the group consisting of biuret reaction, isocyanurate reaction, urethanation reaction, allophanate reaction, iminooxadiazinedione reaction, uretdione reaction, and uretone imino reaction, and by removing the unreacted diisocyanate monomer after the reaction is completed.

[0129] ·Diisocyanates The diisocyanate that is the raw material of the polyisocyanate contained in the polyisocyanate composition (C1) used in this embodiment is one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates.

[0130] The aliphatic diisocyanate used in the present embodiment is not particularly limited, but is preferably an aliphatic diisocyanate having 4 to 30 carbon atoms, such as tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate (hereinafter abbreviated as "HDI"), 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, and lysine diisocyanate. Among these, HDI is more preferable because of its industrial availability. The above-listed aliphatic diisocyanates may be used alone or in combination of two or more.

[0131] The alicyclic diisocyanate used in the present embodiment is not particularly limited, but is preferably an alicyclic diisocyanate having 8 to 30 carbon atoms, such as isophorone diisocyanate (hereinafter abbreviated as "IPDI"), 1,3-bis(isocyanatomethyl)-cyclohexane, 4,4'-dicyclohexylmethane diisocyanate, norbornene diisocyanate, and hydrogenated xylylene diisocyanate. Among them, IPDI is more preferable in terms of weather resistance and industrial availability. The above-mentioned alicyclic diisocyanates may be used alone or in combination of two or more. As the diisocyanate monomer, one or more aliphatic diisocyanates and one or more alicyclic diisocyanates can be used in combination.

[0132] The polyisocyanate composition (C1) used in the present embodiment may further contain a polyisocyanate component obtained from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, and a polyoxyalkylene polyol having an average number of functional groups of 2 to 4.

[0133] The polyisocyanate composition (C1) used in this embodiment can be produced by the methods described in WO 2018 / 163953 and WO 2018 / 163959.

[0134] <Matte agent> The coating composition 2 of this embodiment may further contain a matting agent in addition to the above-mentioned organic polymer hollow particles (B-3). The matting agent is not particularly limited, but examples thereof include dry silica, precipitated silica, organic polymer fine particles, polyethylene wax, etc., which are different from the above-mentioned organic polymer hollow particles (B-3).

[0135] The coating composition 2 may contain the above-mentioned (other components) as necessary.

[0136] <Method of producing coating composition 2> The coating composition 2 of this embodiment is obtained by adding the organic polymer hollow particles (B-3) to the above-mentioned main component while mixing, and then mixing other components as necessary to obtain a coating main component (MC), and then blending the above-mentioned polyisocyanate composition (C1), which is a curing agent component, into the coating main component (MC) and mixing using a known method. At this time, a solvent may or may not be used.

[0137] The coating composition 2 of the present embodiment has a lower viscosity than conventional compositions, and therefore can be produced while maintaining workability even in a high solids formulation.

[0138] <Paint hardener> One embodiment of the present invention is a curing agent for coating materials, comprising a polyisocyanate composition (C1) and organic polymer hollow particles (B-3). In the coating hardener, the content of the organic polymer hollow particles (B-3) relative to the total amount of the polyisocyanate composition (C1) is 10% by weight or more and 200% by weight or less, and more preferably 25% by weight or more and 130% by weight or less. By having the content within the above range, the viscosity of the obtained coating composition and the matte property of the coating film can be compatible within an appropriate range. The solid content of the coating hardener is 70% by weight or more.

[0139] The coating composition 2 of this embodiment may be produced by preparing a coating hardener and mixing the coating hardener with the above-mentioned main component. When preparing the coating curing agent, in addition to the polyisocyanate composition (C1) and the organic polymer hollow particles (B-3), the above-mentioned (other components) may be blended, if necessary. When mixing the coating curing agent with the above-mentioned main component, the above-mentioned (other components) may be added, if necessary. The coating hardener may be prepared or the coating hardener may be mixed with the main component by a known mixing method, with or without the use of a solvent.

[0140] [Application] The use of the coating composition 2 is the same as the method described in <Use> above.

[0141] [Coating film] One aspect of the present invention is a coating film obtained by curing coating composition 2. The description of the coating film obtained by curing coating composition 2 is the same as the method described above in <Coating film>.

[0142] <Method of imparting a matte appearance> One aspect of the present invention is a method for imparting a matte appearance to a cured product of coating composition 2 by adding organic polymer hollow particles (B-3) as a matting agent to coating composition 2 containing a main component and a polyisocyanate composition (C1). EXAMPLES

[0143] The present embodiment will be described in more detail below with reference to examples, but the present embodiment is not limited to these examples. The methods for measuring various physical properties and the methods for evaluating various properties are explained below. Unless otherwise specified, "parts" and "%" mean "parts by mass" and "% by mass".

[0144] Details of the materials used in the examples are as follows:

[0145] Aspartic acid ester compound (A-1): Product name: FEISPARTIC F-420 (Shenzhen Feiyang Protech Co., Ltd.), solid content 97%, amine value 201 Product name: FEISPARTIC F-520 (Shenzhen Feiyang Protech Co., Ltd.), solid content 97%, amine value 191

[0146] Hydroxyl-containing resin compound (A-2): Product name: Acrydic WGU-337 (DIC Corporation), solid content 69%, hydroxyl value 117

[0147] Inorganic fine particles (B-1): Precipitated silica, product name "ACEMATT HK400" (manufactured by Evonik Japan Co., Ltd.), average particle size 6.3 μm, untreated Precipitated silica, product name "ACEMATT OK412" (manufactured by Evonik Japan Co., Ltd.), average particle size 6.3 μm, polyethylene wax treatment

[0148] Organic polymer particles (B-2): Product name: "Tuftic AR650S" (manufactured by Nippon Exlan Co., Ltd.), average particle size: 20 μm Product name: "Tuftic AR650MZ" (manufactured by Nippon Exlan Co., Ltd.), average particle size: 60 μm

[0149] Organic polymer hollow particles (B-3): Product name: Matsumoto Microsphere MFL-81GTA (manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.), average particle size: 20 μm Product name: Matsumoto Microsphere MFL-HD60CA (manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.), average particle size: 61 μm

[0150] Wax particles (B-4): Product name: "CERAFLOUR913" (manufactured by BYK-Chemie), average particle size: 18 μm

[0151] Pigment: Titanium oxide, product name "Tipaque CR-97" (manufactured by Ishihara Sangyo Kaisha, Ltd.) Anti-settling agent: organic bentonite, product name "Bentone SD-2" (manufactured by Elementis) Dehydrating agent: Molecular Sieve 3A (manufactured by Union Showa Co., Ltd.) UV absorber: Product name TINUVIN-1130 (manufactured by BASF) Light stabilizer: Product name TINUVIN-292 (manufactured by BASF) Dispersant: Product name BYK-163 (manufactured by BYK) Defoamer: Product name BYK-141 (manufactured by BYK) Surface conditioner: BYK-331 (manufactured by BYK) Solvent: Butyl acetate

[0152] <Method of measuring physical properties> [Physical Properties 1] (Measurement of the average particle size of matting agent (B)) The measurement was performed by a dry measurement method using a Malvern laser diffraction particle size distribution analyzer (Mastersizer 3000). The average particle size was determined as the D50 value based on volumetric measurement.

[0153] [Physical Property 2] Molar ratio of urethane group / allophanate group Using Biospin Avance600 (trade name) manufactured by Bruker, 13 The molar ratio of urethane groups / allophanate groups was determined by C-NMR measurement. The specific measurement conditions were as follows: 13 C-NMR device: AVANCE600 (manufactured by Bruker) Cryoprobe (Bruker) Cryo Probe CPDUL 600S3-C / HD-05Z Resonance frequency: 150MHz Concentration: 60wt / vol% Shift standard: CDCl3 (77 ppm) Accumulation count: 10,000 times Pulse program: zgpg30 (proton complete decoupling method, waiting time 2 sec) The integral value of the following signals was divided by the number of carbons being measured to obtain the molar ratio of urethane groups / allophanate groups.

[0154] Molar amount of urethane group (mol%): Around 156.5 ppm: integral value ÷ 1 Molar amount of allophanate group (mol%): Around 154 ppm: integral value ÷ 1

[0155] [Physical Properties 3] (NCO content (mass%)) The NCO content (isocyanate content, mass%) of the polyisocyanate composition was measured as follows. After precisely weighing (Wg) 1 g or more and 3 g or less of the polyisocyanate composition produced in the production example in an Erlenmeyer flask, 20 mL of toluene was added to completely dissolve the polyisocyanate composition. Then, 10 mL of a 2N toluene solution of di-n-butylamine was added, and after completely mixing, the mixture was left at room temperature for 15 minutes. Furthermore, 70 mL of isopropyl alcohol was added to this solution and completely mixed. This solution was titrated with a 1N hydrochloric acid solution (factor F) using an indicator to obtain a titration value V2 mL. A similar titration operation was performed without using polyisocyanate to obtain a titration value V1 mL. From the obtained titration values ​​V2 mL and V1 mL, the NCO content (mass%) of the polyisocyanate was calculated based on the following formula.

[0156] (NCO content (mass%))=(V1-V2)×F×42 / (W×1000)×100

[0157] [Physical Properties 4] (Viscosity of polyisocyanate composition (mPa.s)) The viscosity of the polyisocyanate composition was measured at 25° C. using an E-type viscometer (product name: RE-85R, manufactured by Toki Sangyo Co., Ltd.). A standard rotor (1°34′×R24) was used for the measurement. The rotation speed was set as follows.

[0158] (Rotation Speed) 100 rpm (less than 128 mPa s) 50 rpm (128 mPa s or more and less than 256 mPa s) 20 rpm (256 mPa s or more and less than 640 mPa s) 10 rpm (640 mPa s or more and less than 1280 mPa s) 5 rpm (1280 mPa s or more and less than 2560 mPa s) 2.5 rpm (2560 mPa s or more and less than 5120 mPa s) 1.0 rpm (5184 mPa.s or more and less than 12960 mPa.s)

[0159] [Physical Properties 5] (Crystallization of Polyisocyanate Composition) The turbidity of the polyisocyanate composition at room temperature (23° C.) was measured as the transmittance (%) at 550 nm in UV measurement using a JASCO V-650. The measured transmittance was evaluated according to the following evaluation criteria.

[0160] (Evaluation Criteria) A: 550nm transmittance is 70% or more B: Transmittance of 550 nm is less than 70%

[0161] [Physical Properties 6] (number average molecular weight) The number average molecular weight of the polyisocyanate composition was determined as the number average molecular weight based on polystyrene standards by gel permeation chromatography (hereinafter abbreviated as "GPC") measurement using the following device.

[0162] Equipment: Tosoh Corporation "HLC-8120GPC" (product name) Column: Tosoh Corporation "TSKgel SuperH1000" (product name) x 1 "TSKgel SuperH2000" (product name) x 1 "TSKgel SuperH3000" (product name) x 1 Carrier: Tetrahydrofuran Detection method: Differential refractometer

[0163] [Physical Properties 7] Average number of isocyanate groups The average number of isocyanate groups in the polyisocyanate composition was calculated from [Property 1] NCO content and [Property 3] number average molecular weight according to the following formula.

[0164] Average number of isocyanate groups = number average molecular weight × NCO content / 100 / 42

[0165] [Physical Properties 8] Diisocyanate monomer mass concentration (mass%) The diisocyanate mass concentration of the polyisocyanate composition was determined as follows. First, a 20 mL sample bottle was placed on a digital balance and approximately 1 g of the sample was precisely weighed. Next, 0.03 to 0.04 g of nitrobenzene (internal standard solution) was added and precisely weighed. Finally, approximately 9 mL of ethyl acetate was added, and the lid was firmly closed and the mixture was thoroughly mixed to prepare the sample. The prepared sample was analyzed by gas chromatography under the following conditions and quantified.

[0166] Equipment: “GC-8A” manufactured by SHIMADZU Column: "Silicone OV-17" manufactured by Shinwa Kako Co., Ltd. Column oven temperature: 120°C Injection / detector temperature: 160℃

[0167] [Physical Properties 9] (Viscosity of main component (MC) (mPa.s)) The viscosity of the obtained main resin (MC) was measured at 25°C using an E-type viscometer (product name: RE-85R or RE-85U, manufactured by Toki Sangyo Co., Ltd.). A standard rotor (RE-85R: 1°34'×R24, RE-85U: 3°×R14) was used for the measurement. The rotation speed was set as follows:

[0168] (Rotation speed: RE-85R) 100 rpm (less than 128 mPa s) 50 rpm (128 mPa s or more and less than 256 mPa s) 20 rpm (256 mPa s or more and less than 640 mPa s) 10 rpm (640 mPa s or more and less than 1280 mPa s) 5 rpm (1280 mPa s or more and less than 2560 mPa s) 2.5 rpm (2560 mPa s or more and less than 5120 mPa s) (Rotation speed: RE-85U) 100 rpm (less than 5002 mPa s) 50 rpm (5002 mPa s or more and less than 10.0 Pa s) 20 rpm (10.0 Pa s or more and less than 25.01 Pa s) 10 rpm (25.01 Pa s or more and less than 50.02 Pa s) 5 rpm (50.02 Pa s or more and less than 100.0 Pa s) 2.5 rpm (for pressures between 100.0 Pa s and 200.1 Pa s)

[0169] (Evaluation Criteria) S:5000mPa・s or less A: 5001 mPa s or more, less than 20000 mPa s (20.0 Pa s) B: 20001mPa·s (20.0Pa·s) or more

[0170] [Physical Properties 10] (Solid content concentration (%) of coating composition (P)) After weighing an aluminum dish with a bottom diameter of 38 mm, about 1 g of the coating composition (P) of the Example or Comparative Example was weighed out (W1), adjusted to a uniform thickness, and then kept in an oven at 105°C for 3 hours. After the aluminum dish reached room temperature, the coating composition remaining on the aluminum dish was weighed out (W2). The obtained W1 and W2 were then introduced into the following formula to calculate the solid content concentration (%) of the coating composition.

[0171] (Solid content concentration (%) of coating composition (P)) = W2 / W1 × 100

[0172] <How to evaluate coating> [Rating 1] (Appearance of the coating) The coating compositions (P) obtained in the examples and comparative examples were applied to a glass plate with an applicator so that the dry film thickness was 40 μm to 60 μm. After application, the coating was cured for 7 days under conditions of 23° C. and 50 RH% humidity to obtain each coating film. The appearance of each coating film was evaluated according to the following evaluation criteria.

[0173] (Evaluation Criteria) S: The surface is very smooth and no irregularities are observed. A: The surface is smooth, but there are some small irregularities. B: The surface is very uneven and wrinkled.

[0174] [Rating 2] (Matting efficiency (ME) of matting agent (B)) The matting efficiency (ME) of the matting agent (B) was calculated by the following method. The coating composition (P) obtained in the examples and comparative examples was applied to a glass plate with an applicator so that the dry film thickness was 40 μm or more and 60 μm or less. After application, the coating was cured for 7 days under conditions of 23 ° C and humidity 50 RH% to obtain each coating film. Next, the gloss value of this coating film was measured under conditions of 60 ° C - 60 ° C using a gloss meter (Haze-Gloss, manufactured by BYK-Garner), and the gloss value (G1) was obtained.

[0175] The obtained gloss value (G1), the gloss value (G0=95) of the full gloss coating film (coating film not containing a matting agent), and the content of the matting agent (Bw (% by weight): the content of the matting agent (B) relative to the total amount of the aspartic acid ester compound (A-1), the hydroxyl group-containing resin compound (A-2), and the polyisocyanate composition (C) in the obtained coating composition) were introduced into the following formula to calculate the matting efficiency (ME) of the matting agent (B), which was then evaluated according to the following evaluation criteria.

[0176] (Matting efficiency (ME) of matting agent (B)) = (G0-G1) / Bw

[0177] (Evaluation Criteria) S: Matte efficiency (ME) is 4 or more, and the matte property is better A: The matte efficiency (ME) is 2 or more and less than 4, and the matte property is good. B: The matte efficiency (ME) is below 2, and the matte effect is insufficient.

[0178] [Rating 3] (Low temperature elongation of coating film) The coating compositions (P) obtained in the examples and comparative examples were applied to polypropylene (PP) plates with an applicator so that the dry film thickness was 80 μm or more and 100 μm or less. After application, the coatings were cured for 7 days under conditions of 23°C and 50 RH% humidity to obtain each coating film. The elongation of the coating film was measured at a temperature of -20°C using a tensile tester (Orientec, RTE-1210) and a thermostatic bath (Orientec, TLA-R3T-FW) at a tensile speed of 20 mm / min and a gripping distance of 20 mm. The low-temperature elongation of each coating film was evaluated according to the following evaluation criteria.

[0179] (Evaluation Criteria) S: Coating elongation is 30% or more A: Coating elongation is 10% or more but less than 30% B: Coating elongation is less than 10%

[0180] <Production of main component (MC)> [Production Example 1] In a metal container, 33.5 parts of FEISPARTIC F-420 as an aspartic acid ester compound (A-1), 36.9 parts of Typek CR-97 as a pigment, 2.3 parts of BYK-163, 0.35 parts of BYK-141, 1.8 parts of Bentone SD2, 3.5 parts of Molecular Sieve 3A, and 21 parts of butyl acetate as a solvent were charged, and then stirred and mixed with a disperser to obtain a mixture. Next, the entire amount of the mixture obtained and glass beads (the same amount as the total mass of the mixture) were placed in a dispersing machine (manufactured by Taihei System Co., Ltd., tabletop SG Mill 1500W type), and the pigment was dispersed until the particle diameter of the pigment was 20 μm or less, to prepare a pigment dispersion paint. Furthermore, to 99.4 parts of the obtained pigment dispersion paint, 19 parts of ACEMATT HK400 as a matting agent (B), 1.1 parts of TINUVIN-1130, 0.70 parts of TINUVIN-292, and 0.12 parts of BYK-331 as additives, and 18 parts of butyl acetate as a solvent were added, and the mixture was stirred and mixed using a disper until it became uniform, thereby obtaining a base agent (mc-1).

[0181] [Manufacturing Examples 2 to 7] Main agents (mc-2) to (mc-7) were obtained in the same manner as in [Production Example 1], except that the material shown in Table 1 was used as the matting agent (B).

[0182] [Production Example 8] A base compound (mc-8) was obtained in the same manner as in [Production Example 1], except that the material shown in Table 1 was used as the aspartic acid ester compound (A-1).

[0183] [Production Example 9] The main component (mc-9) was obtained in the same manner as in [Production Example 1], except that the material shown in Table 1 was used as the hydroxyl-containing resin compound (A-2) instead of the aspartic acid ester compound (A-1).

[0184] [Examples 10-12] Except for changing the amounts of the materials as shown in Table 1, the same procedure as in [Production Example 2] was followed to obtain main components (mc-10) to (mc-12).

[0185] [Table 1]

[0186] [Comparative Manufacturing Example 1] The main agent (mc-13) was obtained in the same manner as in [Production Example 2], except that the types and amounts of materials were changed as shown in Table 2.

[0187] [Table 2]

[0188] <Production of polyisocyanate composition (C)> [Synthesis Example 1] A nitrogen atmosphere was created in a four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen inlet tube, and a dropping funnel, and 100 parts of HDI and 33.2 parts of Capa2054 (manufactured by Ingevity; number average molecular weight 550, hydroxyl value 204, functionality 2) which is a polycaprolactone polyol were charged. The temperature inside the reactor was kept at 100°C for 2 hours with stirring to carry out a urethane reaction. The cooled reaction liquid was filtered, and unreacted HDI was removed using a thin-film evaporator. A polyisocyanate composition (c-1) was obtained with an NCO content of 9.1% by mass, a viscosity at 25°C of 1460 mPa·s, a number average molecular weight of 1520, an average number of isocyanate groups of 3.3, and an HDI monomer mass concentration of 0.2% by mass. Regarding the obtained polyisocyanate composition (c-1), 13 The molar ratio of urethane groups / allophanate groups determined by C-NMR measurement was 100 / 0.

[0189] [Synthesis Example 2] A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing tube, and a dropping funnel was conditioned with nitrogen, 100 parts of HDI and 33.2 parts of Capa2054 (manufactured by Ingevity; number average molecular weight 550, hydroxyl value 204, functionality 2) which is a polycaprolactone polyol were charged, and the temperature inside the reactor was kept at 100°C for 2 hours while stirring to carry out a urethane reaction. After raising the temperature to 160°C, the temperature was kept for 1 hour to carry out an allophanate reaction. The cooled reaction liquid was filtered, and unreacted HDI was removed using a thin-film evaporator. A polyisocyanate composition (c-2) was obtained, which had an NCO content of 8.4% by mass, a viscosity at 25°C of 1638 mPa·s, a number average molecular weight of 1421, an average number of isocyanate groups of 2.8, and an HDI monomer mass concentration of 0.2% by mass. Regarding the obtained polyisocyanate composition (c-2), 13 The molar ratio of urethane groups / allophanate groups determined by C-NMR measurement was 93 / 7.

[0190] [Synthesis Example 3] A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing tube, and a dropping funnel was conditioned with nitrogen, 100 parts of HDI and 33.2 parts of Capa2054 (manufactured by Ingevity; number average molecular weight 550, hydroxyl value 204, functionality 2) which is a polycaprolactone polyol were charged, and the temperature inside the reactor was kept at 100°C for 2 hours while stirring to carry out a urethane reaction. After raising the temperature to 160°C, the temperature was kept for 2 hours to carry out an allophanate reaction. The cooled reaction liquid was filtered, and unreacted HDI was removed using a thin-film evaporator. A polyisocyanate composition (c-3) was obtained, which had an NCO content of 9.5% by mass, a viscosity at 25°C of 1628 mPa·s, a number average molecular weight of 1528, an average number of isocyanate groups of 3.4, and an HDI monomer mass concentration of 0.2% by mass. The polyisocyanate composition (c-3) obtained was as follows: 13 The molar ratio of urethane groups / allophanate groups determined by C-NMR measurement was 84 / 14.

[0191] [Synthesis Example 4] A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing tube, and a dropping funnel was conditioned with nitrogen, 100 parts of HDI and 33.7 parts of Capa2054 (manufactured by Ingevity; number average molecular weight 550, hydroxyl value 204, functionality 2) which is a polycaprolactone polyol were charged, and the temperature inside the reactor was kept at 100°C for 2 hours while stirring to carry out a urethane reaction. After raising the temperature to 160°C, the temperature was kept for 3 hours to carry out an allophanate reaction. The cooled reaction liquid was filtered, and unreacted HDI was removed using a thin-film evaporator. A polyisocyanate composition (c-4) was obtained, which had an NCO content of 9.8% by mass, a viscosity of 1695 mPa·s at 25°C, a number average molecular weight of 1559, an average number of isocyanate groups of 3.6, and an HDI monomer mass concentration of 0.2% by mass. Regarding the obtained polyisocyanate composition (c-4), 13 The molar ratio of urethane groups / allophanate groups determined by C-NMR measurement was 80 / 20.

[0192] [Synthesis Example 5] A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing tube, and a dropping funnel was filled with nitrogen, and 100 parts of HDI, 6.9 parts of polycaprolactone polyol (number average molecular weight 550, hydroxyl value 305, functionality 3), and 12.8 parts of polytetramethylene glycol (number average molecular weight 1000, hydroxyl value 112, functionality 2) were charged, and the temperature inside the reactor was kept at 90°C for 1 hour while stirring to carry out a urethane reaction. The cooled reaction liquid was filtered, and unreacted HDI was removed using a thin-film evaporator. A polyisocyanate composition (c-5) was obtained with an NCO content of 8.9% by mass, a viscosity at 25°C of 2740 mPa.s, a number average molecular weight of 1570, an average number of isocyanate groups of 3.3, and an HDI monomer mass concentration of 0.2% by mass. The polyisocyanate composition (c-5) obtained was as follows: 13 The molar ratio of urethane groups / allophanate groups determined by C-NMR measurement was 100 / 0.

[0193] [Synthesis Example 6] A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen blowing tube, and a dropping funnel was placed in a nitrogen atmosphere, 2700 parts of HDI and 210 parts of 2-ethylhexanol were charged, and a urethane reaction was carried out at 130°C for 1 hour under stirring. Then, 0.54 parts of a 20% solids solution of 2-ethylhexanoic acid zirconyl in mineral spirits was added as an allophanate catalyst. When the refractive index of the reaction solution increased to 0.0055, 0.81 parts (4.0 times the molar amount relative to the catalyst) of a 50% isobutanol solution of phosphoric acid dodecyl ester (manufactured by Johoku Chemical Industry Co., Ltd., product name "JP-512" diluted with isobutanol) was added to stop the reaction. The cooled reaction solution was filtered, and unreacted HDI was removed using a thin-film evaporator. The obtained polyisocyanate was a transparent liquid, and a polyisocyanate composition (c-6) was obtained having an NCO content of 17.2% by mass, a viscosity at 25°C of 110 mPa.s, a number average molecular weight of 490, an average number of isocyanate groups of 2.0, and an HDI monomer mass concentration of 0.2% by mass. 13 The molar ratio of allophanate groups to isocyanurate groups determined by C-NMR measurement was 97 / 3.

[0194] [Comparative Synthesis Example 1] A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen inlet tube, and a dropping funnel was filled with nitrogen, 100 parts of HDI and 33.2 parts of polycaprolactone polyol Capa2054 (manufactured by Ingevity; number average molecular weight 550, hydroxyl value 204, functionality 2) were charged, and the temperature inside the reactor was kept at 100°C for 2 hours while stirring to carry out a urethane reaction. After the temperature was raised to 130°C, 0.11 g of a 2-ethyl-1-hexanol solution containing 20% ​​by mass of 2-ethylhexanoate zirconyl was added as an allophanate catalyst. When the increase in the refractive index of the reaction solution reached 0.0028, 1.0 g of a 2-ethyl-1-hexanol solution containing 10 mass% pyrophosphoric acid in terms of solid content (produced by diluting Taihei Chemical Industry's product name "Phosphoric Acid (105%)" with 2-ethyl-1-hexanol) was added to terminate the reaction. The cooled reaction solution was filtered, and unreacted HDI was removed using a thin-film evaporator. A polyisocyanate composition (c-7) was obtained with an NCO content of 9.0 mass%, a viscosity at 25°C of 2980 mPa s, a number average molecular weight of 1520, an average number of isocyanate groups of 3.3, and an HDI monomer mass concentration of 0.2 mass%. Regarding the obtained polyisocyanate composition (c-7), 13 The molar ratio of urethane groups / allophanate groups determined by C-NMR measurement was 70 / 30.

[0195] The crystallinity evaluation results of the obtained polyisocyanate composition are shown in Table 3 below.

[0196] [Table 3]

[0197] <Production, application and evaluation of coating composition (P)> [Example 1] A metal container was charged with 127.6 parts of the base agent (mc-1) obtained in the manufacturing and synthesis examples, 61.7 parts of the polyisocyanate composition (c-1), and 6 parts of butyl acetate as a solvent, and then the mixture was stirred and mixed using a disperser to obtain a coating composition (p-1).

[0198] [Examples 2 to 17, Comparative Examples 1 to 3] Except for changing the base resin (MC) and the polyisocyanate composition (C) as shown in Tables 3 and 4, the same procedure as in [Example 1] was carried out to obtain coating compositions (p-2) to (p-20).

[0199] Various physical properties and evaluation results are shown in Tables 4 and 5 below.

[0200] [Table 4]

[0201] [Table 5]

[0202] The solids concentration of the coating compositions of Examples 1 to 17 and Comparative Examples 1 to 3 was 70% by weight or more.

[0203] Since the coating compositions of Examples 1 to 17 and Comparative Examples 1 to 3 have a high ratio of the base resin, whether or not the viscosity is resistant to increase when the solid content is high is evaluated based on the viscosity of the base resin.

[0204] In Tables 4 and 5, the amount of matting agent (B) means the content ratio of the matting agent (B) relative to the total amount of the aspartic acid ester compound (A-1), the hydroxyl group-containing resin compound (A-2) and the polyisocyanate composition (C).

[0205] As shown above, in Examples 1 to 17, even in paints with a high solids concentration of 70% by weight or more, the viscosity of the main component (MC) was kept low at 20,000 mPa s or less, while the elongation of the resulting coating film at -20°C was ensured at the targeted high level of 10% or more. In addition, the matt finish of the coating film was high, enabling the 60 degree gloss to be reduced, and the appearance of the resulting coating film was also good.

[0206] Furthermore, in Examples 1 to 7, in which the type of matting agent was changed to inorganic microparticles, organic polymer microparticles, organic polymer hollow particles, and wax particles, all of the coating compositions were able to achieve the target viscosity, matting efficiency when formed into a coating film, and coating film elongation at -20°C.

[0207] Furthermore, in Examples 10, 11, and 12, in which the amount of matting agent was changed, the greater the amount added, the more the matte properties of the coating film increased, while also achieving the desired level of coating elongation at -20°C.

[0208] On the other hand, in Comparative Example 1 and Comparative Example 2, in which c-7, in which the molar ratio of urethane group / allophanate group is outside the range of the present invention, was used in the polyisocyanate composition (C) serving as the curing agent, the matting efficiency was lower than that in Example 8 and Example 12, in which the same amount of matting agent was contained, and sufficient matting properties were not obtained.

[0209] Moreover, in Comparative Example 3, in which the amount of the matting agent blended was outside the range of the present invention, the coating film elongation at -20°C was extremely decreased.

[0210] The present embodiment will be described in more detail below with reference to examples, but the present embodiment is not limited to these examples. Details of the materials used in the examples are as follows:

[0211] Organic polymer hollow particles (B-3): Matsumoto Microsphere FN-65DE (trade name) manufactured by Matsumoto Yushi Seiyaku Co., Ltd., average particle size = 55 μm, true specific gravity = 0.03 Organic polymer hollow particles (B-3): Matsumoto Microsphere MFL-81GTA (trade name) manufactured by Matsumoto Yushi Seiyaku Co., Ltd., average particle size = 20 μm, true specific gravity = 0.24 Organic polymer hollow particles (B-3): Matsumoto Microsphere MFL-81GCA (trade name) manufactured by Matsumoto Yushi Seiyaku Co., Ltd., average particle size = 18 μm, true specific gravity = 0.25 Organic polymer hollow particles (B-3): Matsumoto Microsphere MFL-30CA (trade name) manufactured by Matsumoto Yushi Seiyaku Co., Ltd., average particle size = 32 μm, true specific gravity = 0.15 Organic polymer hollow particles (B-3): Matsumoto Microsphere MFL-60CA (trade name) manufactured by Matsumoto Yushi Seiyaku Co., Ltd., average particle size = 61 μm, true specific gravity = 0.12 Organic polymer hollow particles (B-3): Matsumoto Microsphere MFL-110CAL (trade name) manufactured by Matsumoto Yushi Seiyaku Co., Ltd., average particle size = 99 μm, true specific gravity = 0.09 Organic Polymers micro Particles: Toughtic AR650S (trade name) manufactured by Nippon Exlan Co., Ltd., average particle size = 18 μm, true specific gravity = 1.29

[0212] Aspartic acid ester compound (A-1): Trade name "FEISPARTIC F-420" (Shenzhen Feiyang Protech Co., Ltd.), solid content concentration 97%, amine value 201 Aspartic acid ester compound (A-1): Trade name "FEISPARTIC F-520" (Shenzhen Feiyang Protech Co., Ltd.), solid content concentration 97%, amine value 191 Hydroxyl-containing resin compound (A-2): Trade name "ACRYDIC WGU-337" (manufactured by DIC Corporation), solid content concentration 69%, hydroxyl value 117 Pigment: Titanium oxide, product name "Tipaque CR-97" (manufactured by Ishihara Sangyo Kaisha, Ltd.)

[0213] Matting agent: precipitated silica, trade name "ACEMATT HK400" (manufactured by Evonik Japan Co., Ltd.), average particle size 6.3 μm Matting agent: precipitated silica, trade name "Nipsil E-170" (manufactured by Tosoh Silica Corporation), average particle size 3.4 μm Matting agent: precipitated silica, trade name "Nipsil E-1011" (manufactured by Tosoh Silica Corporation), average particle size 1.5 μm

[0214] Anti-settling agent: organic bentonite, product name "Bentone SD-2" (manufactured by Elementis) Dehydrating agent: Molecular Sieve 3A (manufactured by Union Showa Co., Ltd.) UV absorber: Product name TINUVIN-1130 (manufactured by BASF) Light stabilizer: Product name TINUVIN-292 (manufactured by BASF) Dispersant: Product name BYK-163 (manufactured by BYK) Defoamer: Product name BYK-141 (manufactured by BYK) Surface conditioner: BYK-331 (manufactured by BYK) Solvent: Butyl acetate

[0215] <Method of measuring physical properties> [Physical properties 1A] (Measurement of true specific gravity d1 of organic polymer hollow particles (B-3)) The true specific gravity d1 of the organic polymer hollow particles (B-3) was measured by the following measurement method. The true specific gravity was measured by the immersion method (Archimedes method) using isopropyl alcohol in an atmosphere with an environmental temperature of 25°C and a relative humidity of 50%. Specifically, a 100cc volumetric flask was emptied and dried, and the weight of the volumetric flask (WB1(g)) was weighed. The weighed volumetric flask was filled with isopropyl alcohol exactly up to the meniscus, and the weight of the volumetric flask filled with 100cc of isopropyl alcohol (WB2(g)) was weighed. The 100cc volumetric flask was emptied and dried, and the weight of the volumetric flask (WS1(g)) was weighed. The weighed volumetric flask was filled with about 50cc of organic polymer hollow particles (B) whose water content was adjusted to less than 1%, and the weight of the volumetric flask filled with organic polymer hollow particles (B-3) (WS2(g)) was weighed. Then, the weight of the volumetric flask filled with organic polymer hollow particles (B-3) after being filled with isopropyl alcohol exactly up to the meniscus without introducing air bubbles (WS3(g)) was weighed. The true specific gravity (d1) of the organic polymer hollow particles (B-3) was calculated as the true density (g / cc) value obtained by introducing the obtained WB1, WB2, WS1, WS2 and WS3 into the following formula.

[0216] (True specific gravity d1 of organic polymer hollow particles (B-3))={(WS2-WS1)×(WB2-WB1) / 100} / {(WB2-WB1)-(WS3-WS2)}

[0217] [Physical properties 2A] (Measurement of the average particle size of organic polymer hollow particles (B-3)) The measurement was performed by a dry measurement method using a Malvern laser diffraction particle size distribution measuring device (Mastersizer 3000). The average particle size was determined as the D50 value based on volumetric measurement.

[0218] [Physical properties 3A] (NCO content (mass%)) The NCO content (isocyanate content, mass%) of the polyisocyanate composition (C1) was measured as follows. After precisely weighing (Wg) 1 g or more and 3 g or less of the polyisocyanate composition produced in the production example in an Erlenmeyer flask, 20 mL of toluene was added to completely dissolve the polyisocyanate composition. Then, 10 mL of a 2N toluene solution of di-n-butylamine was added, and after completely mixing, the mixture was left at room temperature for 15 minutes. Furthermore, 70 mL of isopropyl alcohol was added to this solution and completely mixed. This solution was titrated with a 1N hydrochloric acid solution (factor F) using an indicator to obtain a titration value V2 mL. A similar titration operation was performed without using polyisocyanate to obtain a titration value V1 mL. From the obtained titration values ​​V2 mL and V1 mL, the NCO content (mass%) of the polyisocyanate was calculated based on the following formula.

[0219] (NCO content (mass%))=(V1-V2)×F×42 / (W×1000)×100

[0220] [Physical properties 4A] (Viscosity of polyisocyanate composition (C1) (mPa s)) The viscosity of the polyisocyanate composition (C1) was measured at 25° C. using an E-type viscometer (product name: RE-85R, manufactured by Toki Sangyo Co., Ltd.). A standard rotor (1°34′×R24) was used for the measurement. The rotation speed was set as follows.

[0221] (Rotation Speed) 100 rpm (less than 128 mPa s) 50 rpm (128 mPa s or more and less than 256 mPa s) 20 rpm (256 mPa s or more and less than 640 mPa s) 10 rpm (640 mPa s or more and less than 1280 mPa s) 5 rpm (1280 mPa·s or more and less than 2560 mPa·s) 2.5 rpm (2560 mPa s or more and less than 5120 mPa s) 1.0 rpm (5184 mPa s or more but less than 12960 mPa s)

[0222] [Physical properties 5A] (number average molecular weight) The number average molecular weight of the polyisocyanate composition (C1) was determined as a number average molecular weight based on polystyrene standards by gel permeation chromatography (hereinafter abbreviated as "GPC") measurement using the following device.

[0223] Equipment: Tosoh Corporation "HLC-8120GPC" (product name) Column: Tosoh Corporation "TSKgel SuperH1000" (product name) x 1 "TSKgel SuperH2000" (product name) x 1 "TSKgel SuperH3000" (product name) x 1 Carrier: Tetrahydrofuran Detection method: Differential refractometer

[0224] [Physical properties 6A] (average number of isocyanate groups) The average number of isocyanate groups in the polyisocyanate composition (C1) was calculated from the NCO content ([Property 3]) and the number average molecular weight ([Property 5A]) according to the following formula.

[0225] Average number of isocyanate groups = number average molecular weight × NCO content / 100 / 42

[0226] [Physical properties 7A] (Diisocyanate monomer mass concentration (mass%)) The diisocyanate mass concentration of the polyisocyanate composition (C1) was determined as follows. First, a 20 mL sample bottle was placed on a digital balance and approximately 1 g of the sample was precisely weighed. Next, 0.03 to 0.04 g of nitrobenzene (internal standard solution) was added and precisely weighed. Finally, approximately 9 mL of ethyl acetate was added, and the lid was firmly closed and the mixture was thoroughly mixed to prepare a sample. The prepared sample was analyzed by gas chromatography under the following conditions and quantified.

[0227] Equipment: “GC-8A” manufactured by SHIMADZU Column: "Silicone OV-17" manufactured by Shinwa Kako Co., Ltd. Column oven temperature: 120°C Injection / detector temperature: 160℃

[0228] [Physical Properties 8A] (Viscosity of paint base resin (MC) (mPa·s)) The viscosity of the resulting paint base material (MC) was measured at 25°C using an E-type viscometer (product name: RE-85R or RE-85U, manufactured by Toki Sangyo Co., Ltd.). A standard rotor (RE-85R: 1°34'×R24, RE-85U: 3°×R14) was used for the measurement. The rotation speed was set as follows:

[0229] (Rotation speed: RE-85R) 100 rpm (less than 128 mPa s) 50 rpm (128 mPa s or more and less than 256 mPa s) 20 rpm (256 mPa s or more and less than 640 mPa s) 10 rpm (640 mPa s or more and less than 1280 mPa s) 5 rpm (1280 mPa·s or more and less than 2560 mPa·s) 2.5 rpm (2560 mPa s or more and less than 5120 mPa s) (Rotation speed: RE-85U) 100 rpm (less than 5002 mPa s) 50 rpm (5002 mPa s or more and less than 10.0 Pa s) 20 rpm (10.0 Pa s or more and less than 25.01 Pa s) 10 rpm (25.01 Pa s or more and less than 50.02 Pa s) 5 rpm (50.02 Pa s or more and less than 100.0 Pa s) 2.5 rpm (100.0 Pa s or more and less than 200.1 Pa s)

[0230] (Evaluation Criteria) S:5000mPa・s or less A: 5001 mPa s or more, less than 20000 mPa s (20.0 Pa s) B: 20001mPa·s (20.0Pa·s) or more

[0231] [Physical Properties 9] (Solid content concentration (%) of coating composition (P)) After weighing an aluminum dish with a bottom diameter of 38 mm, about 1 g of the coating composition (P) of the Example or Comparative Example was weighed out (W1), adjusted to a uniform thickness, and then kept in an oven at 105°C for 3 hours. After the aluminum dish reached room temperature, the coating composition remaining on the aluminum dish was weighed out (W2). The obtained W1 and W2 were then introduced into the following formula to calculate the solid content concentration (%) of the coating composition.

[0232] (Solid content concentration (%) of coating composition (P)) = W2 / W1 × 100

[0233] <How to evaluate coating> [Rating 1A] (Appearance of the coating) The coating compositions (P) obtained in the examples and comparative examples were applied to a glass plate with an applicator so that the dry film thickness was 40 μm to 60 μm. After application, the coating was cured for 7 days under conditions of 23° C. and 50 RH% humidity to obtain each coating film. The appearance of each coating film was evaluated according to the following evaluation criteria.

[0234] (Evaluation Criteria) S: The surface is very smooth and no irregularities are observed. A: The surface is smooth, but there are some small irregularities. B: The surface is very uneven and wrinkled.

[0235] [Rating 2A] (Paint film gloss) The coating compositions (P) obtained in the examples and comparative examples were applied to a glass plate with an applicator so that the dry film thickness was 40 μm or more and 60 μm or less. After application, the coatings were cured for 7 days under conditions of 23°C and humidity of 50 RH% to obtain each coating film. The gloss value of the coating film was then measured at 60°-60° using a gloss meter (Haze-Gloss, manufactured by BYK-Garner) and evaluated according to the following evaluation criteria.

[0236] (Evaluation Criteria) A: Gloss value is 40 or less, and matte finish is good B: Gloss value exceeds 40, and matte finish is insufficient.

[0237] [Rating 3A] (Alkaline resistance of coating film) The coating compositions (P) obtained in the examples and comparative examples were applied to a glass plate with an applicator so that the dry film thickness was 40 μm or more and 60 μm or less. After application, the coating was cured for 7 days under conditions of 23°C and humidity of 50 RH% to obtain each coating film. A rubber ring was placed on the obtained coating film, and a 10% by mass aqueous solution of sodium hydroxide was dropped on the center part. After immersion at 23°C for 24 hours, the alkali resistance was evaluated according to the following evaluation criteria based on the state of blisters generated between the glass substrate / coating film.

[0238] (Evaluation Criteria) A: No change in appearance B: Cloudy, eluted, or blistered

[0239] <Manufacture of paint base resin (MC)> [Manufacturing example 1A] A metal container was charged with 33.5 parts of FEISPARTIC F-420 as an aspartic acid ester compound (A-1), 36.9 parts of Typec CR-97 as a pigment, and 2.3 parts of BYK-163, 0.35 parts of BYK-141, 1.8 parts of Bentone SD2, 3.5 parts of Molecular Sieve 3A (abbreviated as "MS 3A" in the table) as additives, and 21 parts of butyl acetate as a solvent, and then the mixture was stirred and mixed with a disperser to obtain a mixture. Next, the entire mixture and glass beads (the same amount as the total mass of the mixture) were put into a dispersing machine (manufactured by Taihei System Co., Ltd., tabletop SG Mill 1500W type), and the pigment was dispersed until the particle diameter of the pigment was 20 μm or less, to prepare a pigment dispersion paint. Furthermore, 19 parts of Matsumoto Microsphere MFL-81GTA as organic polymer hollow particles (B), 1.1 parts of TINUVIN-1130, 0.70 parts of TINUVIN-292, 0.12 parts of BYK-331 as additives, and 18 parts of butyl acetate as a solvent were added to 99.4 parts of the obtained pigment dispersion paint, and the mixture was stirred and mixed using a disperser until it was uniform, to obtain a paint base agent (mc-1).

[0240] [Manufacturing examples 2A to 6A] Coating base materials (mc-2) to (mc-6) were obtained in the same manner as in [Production Example 1], except that the materials shown in Table 1 were used as the organic polymer hollow particles (B).

[0241] [Manufacturing example 7A] A paint base agent (mc-7) was obtained in the same manner as in [Production Example 2], except that the material shown in Table 6 was used as the aspartic acid ester compound (A-1).

[0242] [Manufacturing example 8A] A paint base agent (mc-8) was obtained in the same manner as in [Production Example 2], except that the material shown in Table 7 was used as the hydroxyl-containing resin compound (A-2) instead of the aspartic acid ester compound (A-1).

[0243] [Manufacturing examples 9A to 14A] Except for changing the amounts of materials blended as shown in Table 7, the same procedure as in [Production Example 2A] was followed to obtain paint base agents (mc-9) to (mc-14).

[0244] [Comparative production examples 1A to 5A] Except for changing the types and amounts of materials as shown in Table 8, the same procedure as in [Production Example 1A] was followed to obtain paint base agents (mc-15) to (mc-19).

[0245] [Table 6]

[0246] [Table 7]

[0247] [Table 8]

[0248] <Production of polyisocyanate composition (C1)> [Synthesis Example 1A] A four-neck flask equipped with a stirrer, thermometer, reflux condenser, nitrogen inlet, and dropping funnel was conditioned with nitrogen, and 100 parts of HDI and 33.7 parts of polycaprolactone triol with a number average molecular weight of 850 and a hydroxyl value of 198 were charged. The temperature inside the reactor was kept at 95°C for 90 minutes while stirring, and a urethane reaction was carried out. The cooled reaction liquid was filtered, and unreacted HDI was removed using a thin-film evaporator. A polyisocyanate composition (C1-1) was obtained with an NCO content of 9.0% by mass, a viscosity of 4980 mPa·s at 25°C, a number average molecular weight of 1520, an average number of isocyanate groups of 3.3, and an HDI monomer mass concentration of 0.2% by mass.

[0249] [Synthesis example 2A] A four-neck flask equipped with a stirrer, thermometer, reflux condenser, nitrogen inlet, and dropping funnel was conditioned with nitrogen, and 100 parts of HDI, 6.9 parts of polycaprolactone triol with a number average molecular weight of 550 and a hydroxyl value of 305, and 12.8 parts of polytetramethylene glycol with a number average molecular weight of 1000 and a hydroxyl value of 112 were charged. The temperature inside the reactor was kept at 90°C for 1 hour while stirring, and a urethane reaction was carried out. The cooled reaction liquid was filtered, and unreacted HDI was removed using a thin-film evaporator. A polyisocyanate composition (C1-2) was obtained with an NCO content of 8.9% by mass, a viscosity of 2740 mPa·s at 25°C, a number average molecular weight of 1570, an average number of isocyanate groups of 3.3, and an HDI monomer mass concentration of 0.2% by mass.

[0250] [Synthesis example 3A] A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen inlet tube, and a dropping funnel was placed in a nitrogen atmosphere, 100 parts of HDI was charged, and the temperature inside the reactor was maintained at 60°C while stirring. 0.15 parts of a solution of tetrabutylammonium acetate, an isocyanurate reaction catalyst, diluted to 10% by mass with 2-ethyl-1-hexanol was added thereto, and an isocyanurate reaction was carried out. When the NCO content of the reaction liquid reached 43.8% by mass, phosphoric acid was added to stop the reaction. The reaction liquid was then maintained at 90°C for 1 hour. The cooled reaction liquid was filtered, and unreacted HDI was removed using a thin-film evaporator. A polyisocyanate composition (C1-3) was obtained with an NCO content of 23.1% by mass, a viscosity of 1350 mPa·s at 25°C, a number average molecular weight of 590, an average number of isocyanate groups of 3.2, and an HDI monomer mass concentration of 0.1% by mass.

[0251] <Production, application and evaluation of coating composition (P)> [Example 1A] Into a metal container, 138.4 parts of the base paint (mc-1) obtained in Production Example 1A and Synthesis Example 1A, 61.7 parts of the polyisocyanate composition (C1-1), and 6 parts of butyl acetate as a solvent were charged, and then the mixture was stirred and mixed with a disperser to obtain a paint composition (p-1).

[0252] [Examples 2A to 16A] [Comparative Examples 1A to 5A] Except for changing the base paint (MC) and the polyisocyanate composition (C) as shown in Tables 9, 10, and 11, the same procedure as in Example 1A was carried out to obtain paint compositions (p-2) to (p-21).

[0253] Various physical properties and evaluation results are shown in Tables 9, 10 and 11 below.

[0254] [Table 9]

[0255] [Table 10]

[0256] [Table 11]

[0257] As shown above, in the cases where all of the above-mentioned configurations were satisfied (Examples 1A to 16A), the viscosity of the main component (MC) was low at 20,000 mPa·s or less, and the viscosity increase could be suppressed even in paints with a high solid content concentration of 70% by weight or more. In addition, the matte finish of the coating film was good, at 40 or less at 60° gloss. Furthermore, the appearance and chemical resistance of the resulting coating film were also good.

[0258] In addition, in a comparison of the organic polymer hollow particles in which the average particle size and specific gravity were changed (Examples 1A to 6A), there was a tendency for the matte properties of the coating film to be improved as the average particle size was increased, while the viscosity of the base material tended to be reduced as the specific gravity was increased.

[0259] In addition, in a comparison of the cases where the amount of organic polymer hollow particles was changed (Example 9A, Example 12A, Example 13A, Example 14A), a higher amount tended to improve the matte properties of the coating film, while a lower amount tended to reduce the viscosity of the base agent.

[0260] On the other hand, when silica, which has been used conventionally as a matting agent, was used (Comparative Example 1A and Comparative Example 2A), increasing the amount of silica resulted in too high viscosity, while decreasing the amount of silica resulted in insufficient matting. In addition, paints with poor chemical resistance and high viscosity had poor appearances when made into coating films.

[0261] In addition, instead of organic polymer hollow particles, organic polymers with a high specific gravity are used. micro When particles were used (Comparative Example 5A), the viscosity of the coating material was low, but sufficient matte finish was not obtained.

[0262] Even when the particle size of silica was changed (Comparative Example 3A and Comparative Example 4A), the viscosity became too high compared to (Comparative Example 2A), and sufficient matte finish was not obtained. In addition, the chemical resistance was poor, and the appearance of the coating film was poor. [Industrial Applicability]

[0263] According to the coating composition of the present embodiment, even in a coating material having a high solid content of 70% by weight or more, the amount of the matting agent is reduced to suppress an increase in viscosity, and a coating film having an excellent matte appearance can be efficiently obtained. In addition, the coating film has good elongation at a low temperature of about -20°C.

[0264] According to the coating composition of the present embodiment, even in a coating having a high solid content of 70% by weight or more, the increase in viscosity is suppressed, and the coating has an excellent matte appearance. In addition, when formed into a coating film, the chemical resistance is good.

Claims

1. A coating composition comprising a base agent, a matting agent (B), and a polyisocyanate composition (C), The base material contains either one or both of an aspartic acid ester compound (A-1) and a hydroxyl group-containing resin compound (A-2), the content ratio of the matting agent (B) relative to the total amount of the aspartic acid ester compound (A-1), the hydroxyl group-containing resin compound (A-2) and the polyisocyanate composition (C) is 1% by weight or more and 40% by weight or less; The solid content of the coating composition is 70% by weight or more, The coating composition includes a polyisocyanate component (C-1) derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, and a polyester polyol having an average functionality of 2 or 3 hydroxyl groups, and having a molar ratio of urethane groups / allophanate groups of 100 / 0 to 75 / 25.

2. A coating composition comprising a base agent, a matting agent (B), and a polyisocyanate composition (C), The base material contains either one or both of an aspartic acid ester compound (A-1) and a hydroxyl group-containing resin compound (A-2), the content ratio of the matting agent (B) relative to the total amount of the aspartic acid ester compound (A-1), the hydroxyl group-containing resin compound (A-2) and the polyisocyanate composition (C) is 1% by weight or more and 40% by weight or less; The solid content of the coating composition is 70% by weight or more, The coating composition comprises a polyisocyanate component (C-2) derived from one or more diisocyanates selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates, a polyester polyol having an average functionality of 2 or 3 hydroxyl groups, and a polyoxyalkylene polyol having an average functionality of 2 to 4 hydroxyl groups, and having a molar ratio of urethane groups / allophanate groups of 100 / 0 to 75 / 25.

3. The coating composition according to claim 1 or 2, wherein the matting agent (B) is at least one selected from the group consisting of inorganic fine particles (B-1), organic polymer fine particles (B-2), organic polymer hollow particles (B-3), and wax particles (B-4).

4. 3. The coating composition according to claim 1 or 2, wherein the polyisocyanate composition (C) further comprises a polyisocyanate component (C-3) obtained from at least one diisocyanate selected from aliphatic diisocyanates and alicyclic diisocyanates, and a monoalcohol having 1 to 20 carbon atoms, and having a molar ratio of allophanate groups to isocyanurate groups (allophanate groups / isocyanurate groups) of 100 / 0 to 70 / 30.

5. 2. The coating composition according to claim 1, wherein the molar ratio of urethane groups to allophanate groups in the polyisocyanate component (C-1) is from 99 / 1 to 90 / 10.

6. The coating composition according to claim 2, wherein the molar ratio of urethane groups to allophanate groups in the polyisocyanate component (C-2) is 99 / 1 to 90 / 10.

7. A coating film obtained by curing the coating composition according to claim 1 or 2.

8. The composition comprises an aspartic acid ester compound (A-1) and / or a hydroxyl group-containing resin compound (A-2), and organic polymer hollow particles (B-3), the organic polymer hollow particles (B-3) have a true specific gravity of 0.01 or more and 0.30 or less, an average particle size of 1 μm or more and 100 μm or less, and a content of 10% by weight or more and 200% by weight or less based on the total amount of either or both of the aspartic acid ester compound (A-1) and the hydroxyl group-containing resin compound (A-2), A paint base having a solids concentration of 70% by weight or more.

9. The base for a paint according to claim 8, wherein the organic polymer hollow particles (B-3) are hollow particles constituted by a shell portion made of a thermoplastic resin and a hollow portion surrounded by the shell portion, and particles in which either one or both of the surfaces are further coated with a thermosetting resin.

10. A coating composition comprising the base material for coating according to claim 8 or 9 and a polyisocyanate composition (C1), and having a solids concentration of 70% by weight or more.

11. A coating film obtained by curing the coating composition according to claim 10.

12. A polyisocyanate composition (C1) and organic polymer hollow particles (B-3), the organic polymer hollow particles (B-3) have a true specific gravity of 0.01 or more and 0.30 or less, an average particle size of 1 μm or more and 100 μm or less, and a content of 10% by weight or more and 200% by weight or less based on the total amount of the polyisocyanate composition (C1); A coating hardener having a solids concentration of 70% by weight or more.

13. A method for imparting a matte appearance to a cured product of a coating composition comprising either or both of an aspartic acid ester compound (A-1) and a hydroxyl group-containing resin compound (A-2) and a polyisocyanate composition (C1), by adding organic polymer hollow particles (B-3) having a true specific gravity of from 0.01 to 0.30 and an average particle size of from 1 μm to 100 μm as a matting agent.

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