Coating composition

Abstract

This disclosure aims to provide a coating composition that has a low environmental impact, can be made high-solids, can be spray-coated and dried at room temperature, and produces a coating with good hardness and appearance. [Solution] The solution comprises a polyfunctional (meth)acrylate compound (A) and a polyamine compound (B), The polyfunctional (meth)acrylate compound (A) comprises a polyfunctional acrylate compound (A1) having two or more acryloyl groups in one molecule. The aforementioned polyamine compound (B) is a paint composition comprising an alicyclic polyamine compound (B1) having an alicyclic hydrocarbon group.

Description

Technical Field

[0001] The present disclosure relates to a paint composition.

Background Art

[0002] Industrial machines, construction machines, etc. are generally large-sized and can withstand strong loads, so they are characterized by having a thicker constituent base material (steel plate) compared to automobile bodies, etc. Therefore, when such industrial machines or construction machines are the objects to be painted, there is a problem that the heat capacity of the object to be painted is large and heat is not sufficiently transferred to the object to be painted in the heating furnace. Therefore, when painting such an object to be painted, a room-temperature paint composition capable of forming a paint film even at room temperature without requiring a high-temperature heating step is selected.

[0003] For example, Patent Document 1 describes a paint composition containing a hydroxyl group-containing resin as a base resin, a polyisocyanate compound as a curing agent, and an organotin compound as a urethane curing catalyst, and proposes, among other things, the presence of a phosphate group in the paint composition.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In recent years, in consideration of the environment, reduction of emissions of volatile organic compounds (VOCs) from factories, etc. has been demanded. Since the majority of VOCs in paints are occupied by organic solvents, one of the methods for reducing VOC emissions is to reduce the content of organic solvents, that is, to increase the solid content concentration of the paint composition (high solidification).

[0006] However, with conventional paint compositions, such as the aforementioned paint composition, increasing the solid content significantly increases the viscosity of the paint composition, which can reduce the workability of paint manufacturing and application, as well as the smoothness of the resulting paint film, thus limiting the possibility of increasing the solid content. In addition, the aforementioned paint composition contains free isocyanate groups that are harmful to the human body, resulting in a significant environmental burden, and improvements are desired from an environmental perspective.

[0007] This disclosure aims to provide a coating composition that has a low environmental impact, can be made high-solids, can be spray-coated and dried at room temperature, and produces a coating with good hardness and appearance. [Means for solving the problem]

[0008] This disclosure includes the following aspects: [1] It comprises a polyfunctional (meth)acrylate compound (A) and a polyamine compound (B), The polyfunctional (meth)acrylate compound (A) comprises a polyfunctional acrylate compound (A1) having two or more acryloyl groups in one molecule. The aforementioned polyamine compound (B) is a paint composition comprising an alicyclic polyamine compound (B1) having an alicyclic hydrocarbon group. [2] The paint composition according to [1], wherein the weight-average molecular weight of the polyfunctional (meth)acrylate compound (A) is 200 or more and 3,000 or less. [3] The paint composition according to [1] or [2], wherein the acid value of the polyfunctional (meth)acrylate compound (A) is 40 mg KOH / g or less. [4] The paint composition according to any one of [1] to [3], wherein the hydroxyl value of the polyfunctional (meth)acrylate compound (A) is 80 mg KOH / g or less. [5] The paint composition according to any one of [1] to [4], wherein the weight-average molecular weight of the polyamine compound (B) is 70 or more and 3,000 or less. [6] The paint composition according to any one of [1] to [5], wherein the amine value of the polyamine compound (B) is 10 mg KOH / g or more and 1,600 mg KOH / g or less. [7] The paint composition according to any one of [1] to [6], further comprising a polyfunctional acrylate compound (A1) having three or more acryloyl groups in one molecule. [8] The paint composition according to any one of [1] to [7], wherein the polyamine compound (B) further comprises an aliphatic polyamine compound (B2) having an aliphatic hydrocarbon group. [9] The paint composition according to any one of [1] to [8], wherein the equivalent ratio (acryloyl group / amino group) of the acryloyl group contained in the polyfunctional (meth)acrylate compound (A) and the amino group contained in the polyamine compound (B) is 0.9 or more and 1.2 or less.

[10] A paint composition according to any one of [1] to [9], wherein the content of the film-forming component is 70% by mass or more.

[11] A paint composition according to any one of [1] to

[10] , which is a room temperature drying type and / or a room temperature curing type.

[12] This is a two-component paint composition containing component I and component II. The aforementioned agent I comprises a polyfunctional (meth)acrylate compound (A), The paint composition according to any one of [1] to

[11] , wherein the II agent comprises a polyamine compound (B).

[13] A step of applying a paint composition described in any one of [1] to

[12] to an object to be coated to obtain a paint film, and The process includes drying and / or curing the aforementioned coating film to obtain a coating film, A method for forming a coating film, wherein when applying the aforementioned coating composition, a component I containing a polyfunctional (meth)acrylate compound (A) and a component II containing the polyamine compound are mixed and applied. [Effects of the Invention]

[0009] According to the present disclosure, it is possible to provide a coating composition that has a low environmental impact, can be highly solidified, can be spray-coated and dried at room temperature, and has good hardness and appearance of the obtained coating film.

Mode for Carrying Out the Invention

[0010] The coating composition of the present disclosure contains a polyfunctional (meth)acrylate compound (A) and a polyamine compound (B). The polyfunctional (meth)acrylate compound (A) contains a polyfunctional acrylate compound (A1) having two or more acryloyl groups in one molecule. The polyamine compound (B) contains an alicyclic polyamine compound (B1) having an alicyclic hydrocarbon group.

[0011] The coating composition of the present disclosure has a low environmental impact, can be highly solidified, can be spray-coated and dried at room temperature, and has good hardness and appearance of the obtained coating film. Although the present disclosure should not be construed as being limited to a specific theory, the reasons why the coating composition of the present disclosure can achieve such effects are considered as follows.

[0012] That is, the acryloyl group of the polyfunctional acrylate compound (A1) and the amino group can form a crosslinked structure by the following Michael addition reaction. (Michael addition reaction) -NH2 + CH2=CH-CO-O- → -NH-CH2-CO-O- Compared with the conventional hydroxyl group-containing resin and polyisocyanate compound, the polyfunctional (meth)acrylate compound and polyamine compound of the present disclosure have a low viscosity and can control the drying property. Therefore, it is considered that a coating composition that can achieve environmental load reduction and can be spray-coated and dried at room temperature can be provided. In addition, since the polyfunctional (meth)acrylate compound and the alicyclic polyamine compound are sterically bulky in structure, shrinkage during curing is suppressed, and it is considered that the appearance of the obtained coating film becomes good.

[0013] (A) Polyfunctional (meth)acrylate compound The coating composition contains a polyfunctional (meth)acrylate monomer (A). The polyfunctional (meth)acrylate monomer (A) is a compound having two or more (meth)acryloyl groups in one molecule. In the present disclosure, the (meth)acryloyl group represents an acryloyl group and a methacryloyl group.

[0014] The polyfunctional (meth)acrylate monomer (A) may be any compound having two or more (meth)acryloyl groups in one molecule, and may be a monomer (low molecular weight compound) or an oligomer obtained by polymerization of a plurality of monomers.

[0015] Examples of the (meth)acrylate monomer and / or oligomer having two (meth)acryloyl groups in one molecule include, for example, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 1,6 - hexanediol di(meth)acrylate and nonanediol di(meth)acrylate, di(meth)acrylates of aliphatic diols such as neopentyl glycol di(meth)acrylate; di(meth)acrylates of alicyclic diols such as tricyclodecane dimethylol di(meth)acrylate; di(meth)acrylates of alkylene oxide adducts of isocyanuric acid; Epoxy di(meth)acrylate obtained by reacting an epoxy resin with (meth)acrylic acid; Di(meth)acrylates of alkylene oxide adducts of bisphenol - based compounds such as di(meth)acrylates of alkylene oxide adducts of bisphenol A and di(meth)acrylates of alkylene oxide adducts of bisphenol F (where alkylene o Examples of phosphate adducts include ethylene oxide adducts, propylene oxide adducts, and ethylene oxide and propylene oxide adducts. These are some examples.

[0016] Examples of (meth)acrylate monomers and / or oligomers having three or more (meth)acryloyl groups in one molecule include, for example, glycerin tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane ethylene oxide adduct tri(meth)acrylate, trimethylolpropane propylene oxide adduct tri(meth)acrylate; ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, isocyanurate ethylene oxide adduct tri(meth)acrylate, and polyfunctional urethane(meth)acrylates which are reaction products of hydroxyl group-containing poly(meth)acrylates such as pentaerythritol tri(meth)acrylate with polyisocyanates.

[0017] Commercially available compounds containing two or more (meth)acryloyl groups in one molecule may be used. Examples of commercially available compounds containing two or more (meth)acryloyl groups in one molecule include Aronics M-208, M-211B, M-215, M-220, M-240, M-309, M-310, M-321, M-350, M-360, M-315, M-305, M-450, M-408, M-400, M-402, M-460, M-920, M-930, M-940, etc. (all manufactured by Toagosei Co., Ltd.). DPGDA, HDDA, TPGDA, EBECRYL145, EBECRYL150, IRR214-K, EBECRYL130, PEG400DA-D, EBECRYL11, HPNDA, EBECRYL210, EBECRYL230, EBECRYL280, PETIA, PETRA, TMPTA, EBECRYL TMPTMA, TMPEOTA, EBECRYL135, OTA480, EBECRYL40, EBECRYL140, EBECRYL1142, PETA, DPHA, EBECRYL1290, EBECRYL4265, etc. (all manufactured by Daicel Ornex Corporation); A-HD-N, A-NOD-N, A-DOD-N, A-NPG, 701A, A-200, A-400, A-600, A-1000, APG-200, APG-400, APG-700, A-PTMG65, A-DCP, ABE-300, A-BPE-4, A-BPE-10, A-BPE-20, A-TMPT, A-TMPT-9EO, AT-20E, A-GLY-3E, A-GLY-9E, A-GLY-20E, A-TMM-3, A-TMM-3L, A-TMM-3LM-N, A-TMMT, ATM-35E, AD-TMP, A-DPH, A-9550, A-DPH-12E, etc. (all manufactured by Shin-Nakamura Chemical Industries); These are some examples.

[0018] The above-mentioned polyfunctional (meth)acrylate monomer (A) may be used alone, or two or more may be used in combination.

[0019] The polyfunctional (meth)acrylate compound (A) preferably includes a polyfunctional acrylate compound (A1) having two or more acryloyl groups in one molecule. The presence of acryloyl groups allows the Michael addition reaction between the polyfunctional (meth)acrylate compound and the polyamine compound to proceed smoothly. Examples of the polyfunctional acrylate compound (A1) include compounds in which two or more of the (meth)acryloyl groups are acryloyl groups, as exemplified by the polyfunctional (meth)acrylate compound (A) above.

[0020] The content of polyfunctional acrylate compound (A1) in polyfunctional (meth)acrylate compound (A) is preferably 80% to 100% by mass, more preferably 90% to 100% by mass, and even more preferably 95% to 100% by mass, out of 100% by mass of the total amount of polyfunctional (meth)acrylate compound (A). Being within this range can result in good weather resistance, water resistance, and chemical resistance of the resulting coating film.

[0021] In one embodiment, the polyfunctional (meth)acrylate compound (A) preferably contains a difunctional (meth)acrylate compound having two (meth)acryloyl groups (preferably acryloyl groups) in one molecule. By using a difunctional (meth)acrylate compound, the viscosity of the paint composition can be reduced. Preferred difunctional (meth)acrylate monomers include neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, nonanediol diacrylate, and tricyclodecanedimethanol diacrylate.

[0022] In one embodiment, the content of the difunctional (meth)acrylate compound is preferably 5% to 50% by mass, more preferably 5% to 40% by mass, and even more preferably 5% to 30% by mass, based on 100% by mass of the total amount of the polyfunctional (meth)acrylate compound (A). Being within this range can reduce the viscosity of the resulting paint composition and improve the weather resistance of the resulting coating film. In another embodiment, the content of the difunctional (meth)acrylate compound may be 0% by mass or more, based on 100% by mass of the total amount of the polyfunctional (meth)acrylate compound (A).

[0023] The polyfunctional (meth)acrylate compound (A) preferably contains a trifunctional (meth)acrylate compound having three (meth)acryloyl groups (preferably acryloyl groups) in one molecule. By using a trifunctional (meth)acrylate compound, the paint composition can dry and harden even at room temperature, has particularly good quick-drying properties, and can further increase the mechanical strength of the resulting coating film. Examples of such trifunctional (meth)acrylate compounds include trimethylolpropane triacrylate, glycerin triacrylate, pentaerythritol triacrylate, and trimethylolpropane EO-modified triacrylate.

[0024] In one embodiment, the content of the trifunctional or higher (meth)acrylate compound is preferably 50% to 100% by mass, more preferably 60% to 100% by mass, and even more preferably 70% to 100% by mass, of the total amount of the polyfunctional (meth)acrylate compound (A) by 100% by mass. Being within this range may facilitate the room-temperature drying of the resulting coating composition and may result in a better appearance of the resulting coating film.

[0025] The polyfunctional (meth)acrylate compound (A) preferably contains a tetrafunctional or higher (meth)acrylate compound having four or more (meth)acryloyl groups (preferably acryloyl groups) in one molecule. By using a tetrafunctional or higher (meth)acrylate compound, the quick-drying properties can be improved even at room temperature, and the hardness of the resulting coating film is better. Examples of tetrafunctional or higher (meth)acrylates include ditrimethylolpropanetetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate.

[0026] In one embodiment, the content of the tetrafunctional or more (meth)acrylate compound is preferably 5% to 50% by mass, more preferably 5% to 40% by mass, and even more preferably 5% to 30% by mass, based on 100% by mass of the total amount of the polyfunctional (meth)acrylate compound (A). Being within this range can improve the quick-drying properties even at room temperature, and the hardness of the resulting coating film can be improved. In another embodiment, the content of the tetrafunctional or more (meth)acrylate compound may be 0% by mass or more, based on 100% by mass of the total amount of the polyfunctional (meth)acrylate compound (A). As the polyfunctional (meth)acrylate compound (A), one type may be used, or two or more types may be used in combination.

[0027] The weight-average molecular weight of the polyfunctional (meth)acrylate compound (A) is preferably 200 to 3,000, more preferably 200 to 2,000, and even more preferably 200 to 1,000. Being within this range makes it easier to reduce the viscosity of the coating composition, and the resulting coating film may have good hardness and appearance. In this disclosure, the weight-average molecular weight may be a polystyrene-equivalent value measured by gel permeation chromatography.

[0028] The acid value of the polyfunctional (meth)acrylate compound (A) is preferably 0 mg KOH / g or more and 40 mg KOH / g or less, more preferably 0 mg KOH / g or more and 20 mg KOH / g or less, and even more preferably 0 mg KOH / g or more and 10 mg KOH / g or less. Being within this range can result in good hardness and appearance of the resulting coating film.

[0029] The hydroxyl value of the polyfunctional (meth)acrylate compound (A) is preferably 0 mg KOH / g or more and 80 mg KOH / g or less, more preferably 0 mg KOH / g or more and 40 mg KOH / g or less, and even more preferably 0 mg KOH / g or more and 20 mg KOH / g or less. Being within this range can result in good hardness and appearance of the resulting coating film. In this disclosure, the acid value and hydroxyl value are values ​​based on the coating film-forming components and can be measured in accordance with JIS K 0070.

[0030] The equivalent ratio (acryloyl group / amino group) of the acryloyl group in the polyfunctional (meth)acrylate compound (A) and the amino group in the polyamine compound (B) is preferably 0.9 to 1.2, more preferably 1.0 to 1.2, and even more preferably 1.0 to 1.1. Being within this range can result in good hardness and appearance of the resulting coating film.

[0031] The content of the polyfunctional (meth)acrylate compound (A) may be preferably 10 parts by mass or more and 85 parts by mass or less, more preferably 15 parts by mass or more and 80 parts by mass or less, and even more preferably 20 parts by mass or more and 75 parts by mass or less, based on 100% by mass of the total amount of film-forming components in the paint composition. Being within this range makes it easier to reduce the viscosity of the paint composition, and the hardness and appearance of the resulting coating film may be good.

[0032] In this disclosure, the term "coating film-forming component" refers to a component included in a paint composition that forms a coating film.

[0033] (B) Polyamine compounds Polyamine compound (B) refers to a compound having two or more amino groups in one molecule. Preferably, polyamine compound (B) has a total of two or more of one or more types of amino groups selected from primary and secondary amino groups. Having a compound with two or more primary amino groups can improve the crosslinking density of the coating film.

[0034] The polyamine compound (B) may include, for example, aliphatic polyamine compounds, alicyclic polyamine compounds, aromatic polyamine compounds, polyoxyalkylene group-containing polyamines, polyoxyalkylene group-containing aromatic polyamines, polyamidoamine compounds, and aminosilane compounds, and may also be silicone-modified products thereof.

[0035] The polyamine compound (B) includes an alicyclic polyamine compound (B1) having an alicyclic hydrocarbon group. The inclusion of an alicyclic polyamine compound can result in a coating with good hardness, allowing for increased mechanical strength while maintaining appearance. An alicyclic polyamine compound refers to a polyamine compound having an alicyclic hydrocarbon group.

[0036] Examples of alicyclic polyamine compounds include 1,4-cyclohexanediamine, bis(aminomethyl)cyclohexane, 4,4'-methylenebiscyclohexylamine, 4,4'-methylenebis(2-methylcyclohexylamine), 4,4'-isopropylidenebiscyclohexylamine, 2,5(2,6)-bis(aminomethyl)bicyclo[2.2.1]heptane (e.g., norbornadiamine), and diaminodicyclohexyl Examples include methane (e.g., 4,4'-diaminodicyclohexylmethane), isophoronediamine, mensendiamine (MDA), 1,4-bis-(8-aminopropyl)-piperazine, piperazine-1,4-diazacycloheptane, 1-(2'-aminoethylpiperazine), 1-[2'-(2''-aminoethylamino)ethyl]piperazine, 1,11-diazacycloeicosane, and 1,15-diazacyclooctacosane.

[0037] The content of alicyclic polyamine compound (B1) in polyamine compound (B) is preferably 10% to 100% by mass, more preferably 20% to 100% by mass, and even more preferably 30% to 100% by mass, based on 100% by mass of the total amount of polyamine compound (B). The resulting coating film may have better hardness and appearance.

[0038] The polyamine compound (B) preferably further comprises an aliphatic polyamine compound (B2). An aliphatic polyamine compound means a polyamine compound that contains an aliphatic hydrocarbon group and does not have a ring structure. Examples of aliphatic polyamine compounds include alkylene polyamines, polyalkylene polyamines, and other aliphatic polyamines. Other aliphatic polyamines include aliphatic polyamidoamine compounds and aliphatic aminosilane compounds, which will be described later.

[0039] Examples of alkylene polyamines include methylenediamine, ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, and 1,10-diaminodecane.

[0040] Examples of polyalkylene polyamines include diethylenetriamine, dipropylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexamethylenetetramine, and dipropylenetriamine. Other aliphatic polyamines include, for example, polyamine compounds having oxyalkylene groups such as tetrakis(2-aminoethylaminomethyl)methane, 1,3-bis(2'-aminoethylamino)propane, triethylene-bis(trimethylene)hexamine, bis(3-aminoethyl)amine, bishexamethylenetriamine, polyoxypropylenediamine, trimethylolpropanepoly(oxypropylene)triamine, and glycerylpoly(oxypropylene)triamine.

[0041] In one embodiment, the content of aliphatic polyamine compound (B2) in polyamine compound (B) is preferably 10% to 90% by mass, more preferably 20% to 80% by mass, and even more preferably 30% to 70% by mass, out of 100% by mass of the total amount of polyamine compound (B), and in another embodiment, it is 0% or more by mass.

[0042] Aromatic polyamine compounds refer to polyamine compounds containing aromatic hydrocarbon groups. Examples of aromatic polyamine compounds include aromatic polyamine compounds having an amino group bonded to an aromatic ring, and other aromatic polyamine compounds.

[0043] Examples of aromatic polyamine compounds having an amino group bonded to an aromatic ring include 2,4-diamino-3,5-diethyltoluene, 2,6-diamino-3,5-diethyltoluene, bis(aminoalkyl)benzene, bis(aminoalkyl)naphthalene, and aromatic polyamine compounds having two or more primary amino groups bonded to a benzene ring.

[0044] Other aromatic polyamine compounds include, but are not limited to, bis(cyanoethyl)diethylenetriamine, o-xylylenediamine, m-xylylenediamine (MXDA), p-xylylenediamine, phenylenediamine, naphthylenediamine, diaminodiphenylmethane, diaminodiethylphenylmethane, 2,2-bis(4-aminophenyl)propane, 4,4'-diaminodiphenyl ether, 4,4'-diaminobenzophenone, 4,4'-diaminodiphenylsulfone, 2,2'-dimethyl-4,4'-diaminodiphenylmethane, 3,3'-dichloro-4,4'-diaminodiphenylmethane, 2,4'-diaminobiphenyl, 2,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, bis(aminomethyl)naphthalene, bis(aminoethyl)naphthalene, polytetramethylene oxide-di-p-aminobenzoate, and the like.

[0045] Polyoxyalkylene group-containing polyamines are polyamine compounds having polyoxyalkylene chains that do not fall under the category of "polyoxyalkylene group-containing aromatic polyamines" as described below, i.e., those that do not have aromatic groups. Examples of polyoxyalkylene chains found in polyoxyalkylene group-containing polyamines include polyoxyethylene chains, polyoxypropylene chains, poly(oxyethylene-oxypropylene) chains, and poly(oxytetramethylene) chains.

[0046] Examples of polyoxyalkylene group-containing polyamines include polyoxyethylenediamine, polyoxypropylenediamine, and poly(oxyethylene-oxypropylene)diamine, among other polyoxyalkylenediamines. These are compounds in which a polyoxyalkylene group has been introduced into an aliphatic polyamine, and can also be called polyoxyalkylene group-containing aliphatic polyamines.

[0047] Other polyoxyalkylene group-containing polyamines include, for example, polyamines obtained by reacting polyols such as trimethylolpropane and pentaerythritol with alkylene oxides such as ethylene oxide and / or propylene oxide, and converting two or more hydroxyl groups of the resulting compound into amino groups.

[0048] The weight-average molecular weight of the polyamine containing polyoxyalkylene groups is preferably 100 to 5,000, more preferably 120 to 3,000, and even more preferably 120 to 500. Having the weight-average molecular weight within this range has the advantage of resulting in a good appearance of the resulting coating film. The weight-average molecular weight can be determined by calculation according to the molecular formula of the polyamine compound if the molecular formula is known. Alternatively, the molecular weight may be the number-average molecular weight if the number of repeating oxyalkylene units in the polyoxyalkylene chain is not a natural number.

[0049] Polyoxyalkylene group-containing aromatic polyamines are polyamine compounds having a polyoxyalkylene chain and an aromatic group. Specific examples of the polyoxyalkylene chain are the same as described above.

[0050] Examples of polyoxyalkylene group-containing aromatic polyamines include polyamines obtained by introducing an amino group-containing aromatic compound into a polyol such as a diol, trimethylolpropane, or pentaerythritol, or into an alkylene oxide such as ethylene oxide, propylene oxide, and / or tetramethylene oxide.

[0051] A polyamidoamine compound is a compound that has a polyamide structure in its molecule and contains two or more amino groups. A polyamidoamine compound may be a condensate of a polyamine compound and a polycarboxylic acid compound.

[0052] The polyamine compound used in the production of the polyamidoamine compound is not particularly limited as long as it is a compound having at least two amino groups in its molecule, and at least one selected from the aliphatic polyamine, the alicyclic polyamine, and the aromatic polyamine can be used.

[0053] The polycarboxylic acid compound used in the production of polyamidoamine compounds is not particularly limited as long as it is a compound having at least two carboxyl groups in its molecule, but it is preferably a dicarboxylic acid such as an aliphatic dicarboxylic acid or a dimer acid.

[0054] In the production of polyamidoamine compounds, in addition to polyamine compounds and polycarboxylic acid compounds, aminocarboxylic acid compounds, polyol compounds, lactam compounds, etc. may be reacted as appropriate to produce modified polyamidoamine compounds.

[0055] Examples of aminosilane compounds include compounds having amino groups at both ends of a silicone oil, such as poly(dimethylsiloxane) and poly(diphenylsiloxane).

[0056] A commercially available polyamine compound (B) may be used. Commercially available products include JEFFAMINE M-600, M-1000, D-230, D-2000, EDR-148, T-403, T-3000 (all manufactured by HUNTSMAN Advanced Material); A-5738, E-5493, B-6036, B-2413, X-7000, X-2542, C-6247, D-9650 (manufactured by Daito Sangyo Co., Ltd.); Elastomer series (manufactured by Kumiai Chemical Co., Ltd.); Ancamine 2827, 2604, 2459, Ancamide 261A, 2353, 502, 506, 2137 (manufactured by Evonik); PA-10, PAS-151 (manufactured by Otake Meishinsha Co., Ltd.); Epomin SP-003, SP-006 (manufactured by Nippon Shokubai Co., Ltd.), etc.; Aradur Examples include 3986, 38-1 (manufactured by Huntsman); EPIKURE Curing Agent 8535-W-50, 8530-W-75 (manufactured by Hexion); PAM-E, KF-8010, X-22-161A, X-22-161B, KF-8012, KF-8008, X-22-1660B-3, X-22-9409, KF-8010 (manufactured by Shin-Etsu Silicone Co., Ltd.); and DOWSIL 3055 (manufactured by Dow).

[0057] In one embodiment, the content of the aminosilane compound in the polyamine compound (B) is preferably 10% to 95% by mass, more preferably 20% to 95% by mass, and even more preferably 30% to 95% by mass, out of 100% by mass of the total amount of the polyamine compound (B), and in another embodiment, it is 0% or more by mass.

[0058] One polyamine compound (B) may be used, or two or more may be used in combination.

[0059] The polyamine compound (B) preferably further comprises one or more selected from polyamidoamine compounds and aminosilane compounds. Although it should not be interpreted as being limited to a specific theory, it is thought that the appearance (gloss) of the resulting coating film will be good because amidoamine compounds and / or aminosilane compounds have relatively large molecular weights and structures with high steric hindrance. For example, if a compound with low steric hindrance and a small molecular weight is used as the polyfunctional (meth)acrylate compound (A), the appearance of the resulting coating film may be reduced. However, even in such cases, the appearance (gloss) of the resulting coating film can be improved by using one or more selected from amidoamine compounds and aminosilane compounds.

[0060] Aliphatic compounds are preferred as the polyamidoamine and aminosilane compounds. Including these compounds can result in a low viscosity paint composition and a good appearance of the resulting coating film.

[0061] The total content of one or more compounds selected from amidoamine compounds and aminosilane compounds in polyamine compound (B) is preferably 10% by mass or more and less than 100% by mass, more preferably 20% by mass or more and 95% by mass or less, and even more preferably 30% by mass or more and 95% by mass or less, out of 100% by mass of the total amount of polyamine compound (B). Being within this range can result in better hardness and appearance of the resulting coating film.

[0062] The weight-average molecular weight of the polyamine compound (B) is preferably 70 to 3,000, more preferably 70 to 2,500, and even more preferably 100 to 2,000 or 100 to 1,500. Being within this range makes it easier to reduce the viscosity of the paint composition, and the hardness and appearance of the resulting coating film can be improved.

[0063] The weight-average molecular weight of the aliphatic polyamine compound, alicyclic polyamine compound, or aromatic polyamine compound is preferably 70 to 600, more preferably 70 to 500, and even more preferably 70 to 400. The weight-average molecular weight of the amidoamine compound is preferably 200 to 3,000, more preferably 300 to 2,500 or 400 to 2,000. The weight-average molecular weight of the aminosilane compound is preferably 300 to 3,000, more preferably 400 to 2,500, and even more preferably 500 to 2,000.

[0064] The amine value of polyamine compound (B) is preferably 10 mg KOH / g or more and 1,600 mg KOH / g or less, more preferably 50 mg KOH / g or more and 1,600 mg KOH / g or less, and even more preferably 100 mg KOH / g or more and 1,600 mg KOH / g or less. Being within this range makes it easier to reduce the viscosity of the paint composition and can result in a good appearance of the resulting coating film.

[0065] The amine value of the aliphatic polyamine compound, alicyclic polyamine, or aromatic polyamine compound is preferably 100 mg KOH / g or more and 1,600 mg KOH / g or less, more preferably 200 mg KOH / g or more and 1,600 mg KOH / g or less, and even more preferably 300 mg KOH / g or more and 1,600 mg KOH / g or less. The amine value of the amidoamine compound or aminosilane compound is preferably 10 mg KOH / g or more and 1,500 mg KOH / g or less, more preferably 20 mg KOH / g or more and 1,200 mg KOH / g or less, and even more preferably 50 mg KOH / g or more and 1,000 mg KOH / g or less. In this disclosure, the amine value can be measured in accordance with JIS K 7237.

[0066] The content of polyamine compound (B) may be preferably 25 to 500 parts by mass, more preferably 25 to 400 parts by mass, and even more preferably 25 to 300 parts by mass, per 100 parts by mass of polyfunctional (meth)acrylate compound (A). Being within this range makes it easier to reduce the viscosity of the paint composition and can result in a good appearance of the resulting coating film.

[0067] The content of polyamine compound (B) may be preferably 5 parts by mass or more and 85 parts by mass or less, more preferably 10 parts by mass or more and 75 parts by mass or less, and even more preferably 15 parts by mass or more and 65 parts by mass or less, per 100 parts by mass of the film-forming component in the paint composition.

[0068] ((meth)acrylate monomers) The coating composition of this disclosure may further contain a (meth)acrylate monomer. Including a (meth)acrylate monomer makes it possible to make the coating composition high-solids and impart desired performance to the resulting coating film.

[0069] (Meth)acrylate monomers are typically compounds that have one (meth)acryloyl group in one molecule.

[0070] Examples of the (meth)acrylate monomers include (meth)acrylic acid; alkyl ester (meth)acrylates having a linear or branched alkyl group with 1 to 20 carbon atoms; monomers having a hydroxyl group such as hydroxymethyl (meth)acrylate, hydroxyethyl (meth)acrylate, (hydroxypropyl (meth)acrylate), hydroxybutyl (meth)acrylate, and N-methylol (meth)acrylamide; lactone adducts of the monomers having a hydroxyl group; and (meth)acrylonitrile.

[0071] The above paint composition may optionally contain an organic solvent as a diluent. The organic solvent is not particularly limited and includes, for example, hydrocarbon solvents such as toluene and xylene; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and isophorone; ester solvents such as ethyl acetate, butyl acetate, and ethylene glycol monoethyl ether acetate; alcohol solvents such as methanol, ethanol, and isopropanol; ether alcohol solvents such as ethylene glycol monoethyl ether and diethylene glycol monobutyl ether; amide solvents such as dimethylformamide, diethylformamide, dimethyl sulfoxide, and N-methylpyrrolidone; and cellosolve solvents such as methyl cellosolve, ethyl cellosolve, and butyl cellosolve. These solvents may be used individually or in combination of two or more.

[0072] (Other materials) The aforementioned paint composition may further contain other additives as needed. Examples of such other additives include: extender pigments; colorants such as coloring pigments and dyes; rust-preventive pigments; heat-shielding pigments; lustrous pigments; aggregates (resin particles, silica particles, etc.); waxes; solvents other than those mentioned above; catalysts (acid catalysts, etc.); ultraviolet absorbers (benzophenone-based ultraviolet absorbers, etc.); light stabilizers; antioxidants (phenol-based, sulfoid-based, hindered amine-based antioxidants, etc.); plasticizers; coupling agents (silane-based, titanium-based, zirconium-based coupling agents, etc., preferably silane coupling agents having an amino group); anti-sagging agents; viscosity modifiers; pigment dispersants; pigment wetting agents; surface modifiers (silicone-based, organic polymer-based, etc.); leveling agents; color separation inhibitors; sedimentation inhibitors; settling inhibitors; defoaming agents; surfactants; antifreeze agents; emulsifiers; rust inhibitors; preservatives; antifungal agents; antibacterial agents; stabilizers; dehydrating agents; etc. These additives may be used individually or in combination of two or more.

[0073] Examples of extender pigments include calcium carbonate, barium sulfate, clay, talc, mica, and glass fibers. These may be used individually or in combination of two or more.

[0074] The amount of extender pigment is preferably 1 to 40 parts by mass, more preferably 10 to 30 parts by mass, based on 100 parts by mass of the total of the polyfunctional (meth)acrylate compound (A) and the polyamine compound (B). Having the amount of extender pigment within this range makes it easier to improve the scratch resistance of the coating film.

[0075] Examples of coloring pigments include inorganic pigments such as titanium dioxide, carbon black, graphite, iron oxide, and cold dust; organic pigments such as phthalocyanine blue, phthalocyanine green, quinacridone, perylene, anthrapyrimidine, carbazole violet, anthrapyridine, azo orange, flavanthrone yellow, isoindoline yellow, azo yellow, induthrone blue, dibromanzathrone red, perylene red, azo red, and anthraquinone red; and aluminum powder, alumina powder, bronze powder, copper powder, tin powder, zinc powder, iron phosphide, and finely atomized titanium. These may be used individually or in combination of two or more.

[0076] The amount of coloring pigment is preferably 1 to 40 parts by mass, more preferably 10 to 30 parts by mass, based on 100 parts by mass of the total of the polyfunctional (meth)acrylate compound (A) and the polyamine compound (B). Having the amount of extender pigment within this range makes it easier to improve the scratch resistance of the coating film.

[0077] A heat-shielding pigment refers to a pigment that does not absorb light in the near-infrared wavelength range (wavelength: 780nm to 2,500nm) or has a low absorption rate of light in the near-infrared wavelength range (wavelength: 780nm to 2,500nm). The heat-shielding pigment is not particularly limited, and the following inorganic and organic heat-shielding pigments can be used.

[0078] Examples of inorganic heat-shielding pigments include metal oxide pigments such as titanium dioxide, magnesium oxide, barium oxide, calcium oxide, zinc oxide, zirconium oxide, yttrium oxide, indium oxide, sodium titanate, silicon oxide, nickel oxide, manganese oxide, chromium oxide, iron oxide, copper oxide, cerium oxide, and aluminum oxide; iron oxide-manganese oxide, iron oxide-chromium oxide (for example, Dainichi Seika's Dipyroxide Color Black #9595, Asahi Kasei Kogyo's Black 6350), and iron oxide-cobalt oxide-chromium oxide (for example, Dainichi Seika's Dipyroxide Color Brown). Examples include composite oxide pigments such as #9290, dipyroxide color black #9590), copper oxide-magnesium oxide (e.g., dipyroxide color black #9598 from Dainichi Seika Co., Ltd.), manganese oxide-bismuth oxide (e.g., Black 6301 from Asahi Kasei Kogyo Co., Ltd.), and manganese oxide-yttrium oxide (e.g., Black 6303 from Asahi Kasei Kogyo Co., Ltd.); metallic pigments such as silicon, aluminum, iron, magnesium, manganese, nickel, titanium, chromium, and calcium; and alloy pigments such as iron-chromium, bismuth-manganese, iron-manganese, and manganese-yttrium. These may be used individually or in combination of two or more.

[0079] Examples of organic heat-shielding pigments include azo pigments, azomethine pigments, lake pigments, thioindigo pigments, anthraquinone pigments (anthanthrone pigment, diaminoanthraquinonyl pigment, indanthrone pigment, flavanthrone pigment, anthrapyrimidine pigment, etc.), perylene pigments, perinone pigments, diketopyrrolopyrrole pigments, dioxazine pigments, phthalocyanine pigments, quiniphthalone pigments, quinacridone pigments, isoindoline pigments, isoindolinone pigments, etc. These may be used individually or in combination of two or more.

[0080] Examples of the aforementioned luminous pigments include foil pigments such as aluminum foil, bronze foil, tin foil, gold foil, silver foil, titanium metal foil, stainless steel foil, nickel-copper alloy foil, and foil-like phthalocyanine blue. These may be used individually or in combination of two or more.

[0081] The coating composition of this disclosure is preferably a two-component coating composition comprising a component I and a component II. Components I and II are stored separately after manufacture and mixed immediately before use. In this embodiment, the polyfunctional (meth)acrylate compound (A) and the polyamine compound (B) are preferably contained in different components. In one embodiment, component I preferably contains the polyfunctional (meth)acrylate compound (A) and component II preferably contains the polyamine compound (B), but is not limited thereto.

[0082] The content of the film-forming component in the coating composition of this disclosure is preferably 70% by mass or more and 100% by mass or less, more preferably 80% by mass or more and 100% by mass or less, and even more preferably 90% by mass or more and 100% by mass or less. The coating composition of this disclosure contains a polyfunctional (meth)acrylate compound (A) and a polyamine compound (B), which can be easily made high-solid.

[0083] The coating compositions of this disclosure are preferably room temperature drying and / or room temperature curing. In such embodiments, "room temperature" may be, for example, 5 to 45°C or 10 to 40°C.

[0084] <Method for preparing paint composition> The method for preparing the paint composition of this disclosure is not particularly limited and can be prepared by mixing each component. For example, it can be mixed using a roller mill, ball mill, bead mill, pebble mill, sand grind mill, pot mill, paint shaker, disperser, or other mixer, disperser, or kneader. The technical scope of this disclosure also includes coating films formed from paint compositions and methods for manufacturing said coating films.

[0085] <Object to be coated> Examples of substrates to be coated with the coating compositions of this disclosure include galvanized steel sheets, zinc-aluminum alloy coated steel sheets, aluminum alloy coated steel sheets, hot-dip zinc-aluminum-magnesium alloy coated steel sheets, stainless steel sheets, cold-rolled steel sheets, etc., manufactured by melting or electrolytic methods. In addition to these steel sheets or coated steel sheets, metal sheets such as aluminum sheets (including aluminum alloy sheets) can also be coated.

[0086] The workpiece to be coated is preferably surface-treated. Specifically, the workpiece to be coated is preferably subjected to a chemical conversion treatment after undergoing pretreatment such as alkaline degreasing, hot water washing, or water washing. The chemical conversion treatment may be carried out by known methods, and includes, for example, non-chromate treatments such as chromate treatment and zinc phosphate treatment. The surface treatment can be appropriately selected depending on the steel sheet used, but treatments that do not contain heavy metals are preferred. By applying the paint composition of this disclosure onto a workpiece that has undergone such chemical conversion treatment, the adhesion of the coating film to the metal sheet surface is improved, as is the corrosion resistance. Alternatively, an undercoat coating (primer coating) can be formed on the metal sheet surface that has undergone chemical conversion treatment, and the coating can be applied on top of that. The thickness of the undercoat coating is preferably 3 μm to 30 μm, more preferably 5 to 20 μm.

[0087] <Method for manufacturing coating film> The method for manufacturing a coating film according to the present disclosure includes the steps of applying the coating composition according to the present disclosure to an object to be coated to form a coating film, and drying and / or curing the coating film to obtain a coating film.

[0088] The method for applying the coating composition of this disclosure to an object to be coated is not particularly limited, but conventionally known methods such as the roll coater method, airless spray method, electrostatic spray method, and curtain flow coater method can be used. Preferably, the roll coater method and the curtain flow coater method are mentioned, and more preferably the roll coater method.

[0089] When the coating composition is a two-component curing type containing Agent I and Agent II, the mixing time of Agent I and Agent II is not limited. For example, Agent I and Agent II may be mixed before use and then applied by a normal coating method. Preferably, each of Agent I and Agent II may be fed to the gun with a two-component mixing gun and applied by a method of mixing at the tip of the gun.

[0090] The drying and / or curing may be carried out at room temperature (for example, 5 to 45 °C, preferably 10 to 40 °C), or may be forced to dry at, for example, 60 to 80 °C. The period of drying and / or curing may be, for example, 30 minutes to 1 week, 1 day to 1 week when carried out at room temperature, or 30 minutes to 1 hour when forced to dry.

[0091] The film thickness (dry film thickness) of the coating film after drying and / or curing is preferably 10 to 100 μm, more preferably 15 to 80 μm.

[0092] A laminate having the object to be coated and the coating film formed on the object to be coated is also included in the technical scope of the present disclosure.

[0093] When the object to be coated further has the coating film on one surface, it may have a coating film formed from a known coating composition such as a coating composition containing an epoxy resin on the other surface.

[0094] The coating composition of the present disclosure has a low environmental impact, can be high-solids, can be spray-coated and dried at room temperature, and the hardness and appearance of the resulting coating film can be good. Therefore, the coating composition of the present disclosure is preferably used for coating industrial machines, construction machines, etc.

Examples

[0095] The present invention will be described more specifically by the following examples, but the present invention is not limited thereto.

[0096] Each component used for the preparation of the coating composition is as follows.

[0097] <Manufacture of Agent I> A mixture was obtained by mixing 45 parts by mass of trimethylolpropane triacrylate as polyfunctional (meth)acrylate compound (A-3), 14 parts by mass of Aronics M940 as polyfunctional (meth)acrylate compound (A-6), 4 parts by mass of Novoperm Orange HL70-JP as pigment 1, and 2 parts by mass of TIPAQUE CR-95 as pigment 2.

[0098] Next, the entire amount of the obtained mixture and glass beads (in the same amount as the total mass of the mixture) were placed in a tabletop SG Mill 1500W disperser (manufactured by Ohira Systems Co., Ltd.), and the pigment was dispersed until the particle size of the pigment was 10 μm or less, thereby preparing a pigment dispersion solution and obtaining Agent I 1.

[0099] <Manufacturing of hardening agents> As the polyamine compound (B-2), 1,3-bisaminomethylcyclohexane was used as the II agent 1.

[0100] <Example of preparation of paint composition 1> The 65 parts by mass of Agent I 1 and 21 parts by mass of Agent II 1 obtained above were mixed using a disperser and stirred until homogeneous to obtain paint composition 1. Agents I and II were mixed such that the equivalent ratio (acryloyl group / amino group) of the total amount of acryloyl groups contained in the polyfunctional (meth)acrylate compounds (A-3) and (A-6) to the amino groups contained in the polyamine compound (B-2) was 1.0.

[0101] <Example of test plate preparation> The paint composition obtained above was applied to the surface of a steel plate (JIS G 3141, SPCC-SB steel plate, 70 × 150 × 0.8 mm: manufactured by TP Giken Co., Ltd.) using an air spray gun to achieve a dry film thickness of 40 μm. The plate was dried at room temperature (25°C) for one week to obtain an evaluation test plate.

[0102] <Examples 2-11 and Comparative Examples 1-18> A paint composition was prepared in the same manner as in Example 1, except that the type and / or amount of each component was changed to the amounts shown in Tables 1 and 2.

[0103] An evaluation test plate having a coating film was obtained in the same manner as in Example 1, except that a coating film was formed using the coating composition prepared above.

[0104] The details of each component listed in Table 1 are as follows: (A) Polyfunctional (meth)acrylate compound (A-1) 1,6-Hexanediol diacrylate: bifunctional acrylate, manufactured by Daicel Ornex; weight-average molecular weight: 226, acid value: 0.1 mg KOH / g, hydroxyl value: 1 mg KOH / g or less, film-forming component concentration: 100% by mass (A-2) EBECRYL 130; Tricyclodecanedimethanol diacrylate: bifunctional acrylate, manufactured by Daicel Ornex; weight-average molecular weight: 300, acid value: 0.4 mg KOH / g, hydroxyl value: 1 mg KOH / g or less, film-forming component concentration: 100% by mass (A-3) Trimethylolpropane triacrylate: Trifunctional acrylate, manufactured by Daicel Ornex; Weight-average molecular weight: 296, Acid value: 0.1 mg KOH / g, Hydroxyl value: 10-20 mg KOH / g, Film-forming component concentration: 100% by mass (A-4) Aronics M930; Glycerin triacrylate: Trifunctional acrylate, manufactured by Toagosei Co., Ltd.; Weight-average molecular weight: 254, Acid value: 1 mg KOH / g or less, Hydroxyl value: 30 mg KOH / g, Film-forming component concentration: 100% by mass (A-5) Aronics M408; Di(trimethylolpropane)tetraacrylate: Tetrafunctional acrylate, manufactured by Toagosei Co., Ltd.; Weight-average molecular weight: 467, Acid value: 1 mg KOH / g or less, Hydroxyl value: 35-45 mg KOH / g, Film-forming component concentration: 100% by mass (A-6) Aronics M940; Dipentaerythritol Hexaacrylate: Hexafunctional acrylate, manufactured by Toagosei Co., Ltd.; Weight-average molecular weight: 579, Acid value: 1 mg KOH / g or less, Hydroxyl value: 40-50 mg KOH / g, Film-forming component concentration: 100% by mass (a-1) 8BR-600; Modified acrylic urethane resin: Acrylate polymer, manufactured by Taisei Fine Chemical Co., Ltd.; Weight-average molecular weight: 100,000, Acid value: 1 mg KOH / g or less, Hydroxyl value: 1 mg KOH / g or less, Film-forming component concentration: 38% by mass (a-2) 8KQ-2001; Modified acrylic resin: methacrylate polymer, manufactured by Taisei Fine Chemical Co., Ltd.; Weight-average molecular weight: 20,000, Acid value: 130 mg KOH / g, Hydroxyl value: 102 mg KOH / g, Film-forming component concentration: 40% by mass (a-3) EBECRYL TMPTMA; Trimethylolpropane Trimethacrylate: Trifunctional methacrylate, manufactured by Daicel Ornex; Weight-average molecular weight: 338, Acid value: 1 mg KOH / g or less, Hydroxyl value: 1 mg KOH / g or less, Film-forming component concentration: 100% by mass (B) Polyamine compounds (B-1) 4,4'-Methylenebis(aminocyclohexane): Alicyclic diamine, manufactured by Evonik; weight-average molecular weight: 210, amine value: 533 mgKOH / g, film-forming component concentration: 100% by mass (B-2) 1,3-Bisaminomethylcyclohexane: Alicyclic diamine, manufactured by Mitsubishi Gas Chemical Company; weight-average molecular weight: 142, amine value: 789 mgKOH / g, film-forming component concentration: 100% by mass (b-1) Metaxylenediamine: Aromatic diamine, manufactured by Mitsubishi Gas Chemical Company; weight-average molecular weight: 136, amine value: 824 mgKOH / g, film-forming component concentration: 100% by mass (b-2) Bis(3-aminopropyl)amine: Aliphatic triamine, manufactured by BASF; weight-average molecular weight: 131, amine value: 1283 mgKOH / g, film-forming component concentration: 100% by mass (b-3) Diethylenetriamine: Aliphatic triamine, manufactured by Tosoh Corporation; weight-average molecular weight: 103, amine value: 1,631 mgKOH / g, film-forming component concentration: 100% by mass (b-4) Ethylenediamine: Aliphatic diamine, manufactured by Tosoh Corporation; weight-average molecular weight: 60, amine value: 1,867 mgKOH / g, film-forming component concentration: 100% by mass (b-5) PAS-151; Aliphatic amidoamine, manufactured by Ohtake Meishin Chemical Co., Ltd.; Weight-average molecular weight: 450, Amine value: 397 mg KOH / g, Film-forming component concentration: 100% by mass (b-6) KF-8010; End-modified aliphatic aminosilane, manufactured by Shin-Etsu Silicone Co., Ltd.; Weight-average molecular weight: 860, Amine value: 430 mg KOH / g, Film-forming component concentration: 100% by mass (b-7) DOWSIL 3055; End-modified aliphatic aminosilane, manufactured by DOW; Weight-average molecular weight: 1,300, Amine value: 272 mg KOH / g, Film-forming component concentration: 100% by mass Other materials: Pigment 1: NOVOPERM ORANGE HL70, organic pigment, manufactured by Clariant. Pigment 2: Typake CR-95; Titanium dioxide, manufactured by Ishihara Sangyo Co., Ltd.

[0105] (3) Evaluation items 1) Viscosity of the paint composition The components I and II obtained in the examples and comparative examples were mixed according to the formulations shown in Table 1 and stirred in a disperser for 1 minute (paint mixture). Immediately after stirring, the viscosity of the paint mixture was measured at 25°C using a viscosity cup NK2 (manufactured by Anest Iwata Corporation). A value of less than 40 seconds was considered acceptable, and a value of less than 30 seconds was judged to indicate better viscosity.

[0106] 2)Drying property The drying time of the paint film formed from the paint composition after application was measured to reach a touch-dry state according to the provisions of JIS K 5600-1-1, and the drying performance of the paint film was evaluated. A drying time of 40 minutes or less was considered acceptable, and a drying time of 30 minutes or less was judged to be better.

[0107] 3) Gloss value The gloss values ​​at 60° and 20° of the surface of each coating obtained in the examples and comparative examples were measured using a gloss meter (Micro-Tri-Gloss, BYK Gardner). The evaluation criteria were as follows: A value of 80 or higher was considered acceptable, and a value of 90 or higher was judged to have better gloss.

[0108] 4)Hardness: The pencil hardness of the coating film was measured using the coated steel sheets obtained in the examples and comparative examples, in accordance with JIS K 5600-5-4. Specifically, a pencil (manufactured by Mitsubishi Pencil Co., Ltd.: for scratch hardness testing by the Japan Paint Inspection Association) was pressed against the surface of the hardened electrodeposited coating at a 45° scratching angle and moved, and the presence or absence of scratches from the pencil lead was visually observed. For example, in a test using an H pencil, if no scratches were observed, it was judged to be H or higher. If a slight indentation was visually observed in one of the five tests, it was judged to be H. If indentations were observed in two or more of the five tests, it was judged to be less than H, and the evaluation was similarly lowered by one level. F or higher was considered a passing grade, and H or higher was judged to have better hardness.

[0109] [Table 1]

[0110] [Table 2]

[0111] Examples 1 to 11 are embodiments of the present invention, and the resulting paint composition was able to be made low in viscosity, had good drying properties, and the resulting coating film had good gloss and hardness.

[0112] Comparative Examples 1 to 17 are examples in which the polyamine compound (B) does not contain an alicyclic polyamine compound (B1) having an alicyclic hydrocarbon group, and the viscosity of the resulting paint composition, the drying properties of the resulting coating film, the gloss value, and the hardness of at least one of these properties were inferior. Comparative Example 18 is an example in which the polyfunctional (meth)acrylate compound (A) does not contain a polyfunctional acrylate compound (A1) having two or more acryloyl groups in one molecule, and the resulting coating film had poor drying properties and hardness. [Industrial applicability]

[0113] The paint composition disclosed herein has a low environmental impact, can be made high-solids, can be spray-applied and dried at room temperature, and the resulting coating film has good hardness and appearance. For this reason, the paint composition disclosed herein is preferably used for painting industrial machinery, construction machinery, and the like.

Claims

1. It comprises a polyfunctional (meth)acrylate compound (A) and a polyamine compound (B), The polyfunctional (meth)acrylate compound (A) comprises a polyfunctional acrylate compound (A1) having two or more acryloyl groups in one molecule. The polyamine compound (B) is a paint composition comprising an alicyclic polyamine compound (B1) having an alicyclic hydrocarbon group.

2. The paint composition according to claim 1, wherein the weight-average molecular weight of the polyfunctional (meth)acrylate compound (A) is 200 or more and 3,000 or less.

3. The paint composition according to claim 1, wherein the acid value of the polyfunctional (meth)acrylate compound (A) is 40 mg KOH / g or less.

4. The paint composition according to claim 1, wherein the hydroxyl value of the polyfunctional (meth)acrylate compound (A) is 80 mg KOH / g or less.

5. The paint composition according to claim 1, wherein the weight-average molecular weight of the polyamine compound (B) is 70 or more and 3,000 or less.

6. The paint composition according to claim 1, wherein the amine value of the polyamine compound (B) is 10 mg KOH / g or more and 1,600 mg KOH / g or less.

7. The paint composition according to claim 1, wherein the polyfunctional acrylate compound (A1) further comprises a polyfunctional acrylate compound having three or more acryloyl groups in one molecule.

8. The paint composition according to claim 1, wherein the polyamine compound (B) further comprises an aliphatic polyamine compound (B2) having an aliphatic hydrocarbon group.

9. The paint composition according to claim 1, wherein the equivalent ratio (acryloyl group / amino group) of the acryloyl group contained in the polyfunctional (meth)acrylate compound (A) and the amino group contained in the polyamine compound (B) is 0.9 or more and 1.2 or less.

10. The paint composition according to claim 1, wherein the content of the film-forming component is 70% by mass or more.

11. The paint composition according to claim 1, which is a room temperature drying type and / or a room temperature curing type.

12. It is a two-component paint composition containing component I and component II. The aforementioned agent I comprises a polyfunctional (meth)acrylate compound (A), The paint composition according to claim 1, wherein the II agent comprises a polyamine compound (B).

13. A step of applying a coating composition according to any one of claims 1 to 12 to an object to be coated to obtain a coating film, and The process includes drying and / or curing the aforementioned coating film to obtain a coating film, A method for forming a coating film, wherein when applying the aforementioned coating composition, a component I containing a polyfunctional (meth)acrylate compound (A) and a component II containing the polyamine compound are mixed and applied.

Images