Antifouling coating composition

Abstract

The present invention provides an antifouling coating composition capable of maintaining an excellent coating film surface state for a long period of time and maintaining high drying properties for antifouling performance. According to the present invention, an antifouling coating composition is provided, comprising a copolymer A and an antifouling agent, wherein the copolymer A is a copolymer of a monomer (a) represented by the following general formula (1) and an ethylenically unsaturated monomer (b) other than monomer (a). The monomer (a) comprises a compound wherein n in the general formula (1) is 2 or greater, and the weight-average molecular weight of the copolymer A is 5,000 to 25,000.

Description

Technical Field

[0001] The present invention relates to an antifouling coating composition. Background Art

[0002] Aquatic fouling organisms such as barnacles, serrated algae, mussels, mosses, ascidians, green laver, sea lettuce, and sludge attach to ships (especially the bottoms), fishing nets, fishing net accessories, and other fishing tools, as well as underwater structures such as power plant water pipes, causing problems such as functional impairment and deterioration of the appearance of ships.

[0003] In order to prevent such problems, techniques are known in which an antifouling coating composition is applied to a ship or the like to form an antifouling coating film, and the antifouling agent is slowly released from the antifouling coating film to provide long-term antifouling performance (Patent Documents 1 to 4).

[0004] However, the antifouling coating films composed of polymers containing an alkoxycarbonylmethyl (meth)acrylate group described in Patent Documents 1 to 4 have very low solubility, and therefore it is difficult to exhibit antifouling properties for a long period of time.

[0005] In order to solve these problems, a technology has been proposed that can dissolve the coating film for a long period of time and exhibit antifouling performance (Patent Document 5).

[0006] Prior art documents

[0007] Patent Literature

[0008] [Patent Document 1] Japanese Patent Publication No. 63-61989

[0009] [Patent Document 2] Japanese Patent Application Laid-Open No. 2003-119420

[0010] [Patent Document 3] Japanese Patent Application Laid-Open No. 2003-119419

[0011] [Patent Document 4] Japanese Patent No. 2002-3776

[0012] [Patent Document 5] International Publication No. 2020 / 045211 Summary of the Invention

[0013] Technical problem to be solved by the invention

[0014] The antifouling coating film formed from the antifouling coating composition described in Patent Document 5 has improved solubility, but has a problem of insufficient drying of the coating film if sufficient drying time is not obtained during film formation.

[0015] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a highly drying antifouling coating composition capable of maintaining excellent coating film surface conditions and antifouling performance for a long period of time.

[0016] Methods used to solve problems

[0017] According to the present invention, there is provided an antifouling coating composition comprising a copolymer A and an antifouling agent, wherein the copolymer A is a copolymer of a monomer (a) represented by the general formula (1) and an ethylenically unsaturated monomer (b) other than the monomer (a), wherein the monomer (a) comprises a compound represented by the general formula (1) wherein n is 2 or greater, and the weight-average molecular weight of the copolymer A is 5,000 to 25,000.

[0018] The present inventors have conducted intensive studies to solve the above-mentioned problems and, as a result, have found that a composition containing copolymer A and an antifouling agent can solve the above-mentioned problems, thereby completing the present invention. DETAILED DESCRIPTION

[0019] The present invention is described in detail below.

[0020] 1. Antifouling coating composition

[0021] The antifouling coating composition of the present invention contains copolymer A and an antifouling agent.

[0022] 1-1. Copolymer A

[0023] Copolymer A is a copolymer of monomer (a) and an ethylenically unsaturated monomer (b) other than monomer (a), and contains monomer (a) and monomer units derived from monomer (b). The content of monomer (a) is preferably 10 to 90% by mass, more preferably 20 to 70% by mass, relative to the total of monomers (a) and (b). Specifically, for example, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90% by mass, or within the range of any two of the values ​​exemplified herein. In this case, the coating film solubility is particularly good.

[0024] 1-1-1. Monomer (a)

[0025] Monomer (a) is represented by general formula (1).

[0026] [Chemistry 1]

[0027]

[0028] Where R 1 represents hydrogen or methyl, R 2 represents hydrogen, methyl or phenyl, R 3 represents an alkyl group or phenyl group having 1 to 8 carbon atoms which may be substituted with an alkoxy group or phenyl group having 1 to 8 carbon atoms, and n represents an integer of 1 to 10.

[0029] R2 Preferred are hydrogen or methyl.

[0030] R 3 The number of carbon atoms in the alkoxy group or alkyl group is, for example, 1, 2, 3, 4, 5, 6, 7, or 8, and may be within the range between any two of the values ​​exemplified here. 3 It is, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, 2-ethylhexyl, cyclohexyl, benzyl, phenyl, 2-methoxyethyl, 4-methoxybutyl, vinyl or allyl, preferably methyl, ethyl, isopropyl or n-butyl.

[0031] n represents an integer of 1 to 10, and n is, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10, and may be within the range between any two of the exemplified values.

[0032] Monomer (a) includes a compound in which n in the general formula (1) is 2 or greater. When a compound in which n is 2 or greater is included as monomer (a), the solubility of the coating film is improved. Monomer (a) may consist solely of a compound in which n is 2 or greater, or may be a mixture of a compound in which n is 1 and a compound in which n is 2 or greater.

[0033] Monomer (a) is preferably composed of monomer (a1) and monomer (a2). The content of monomer (a1) in monomer (a) is preferably 50 to 80% by mass, more preferably 55 to 75% by mass, and particularly preferably 60 to 70% by mass. Compared with monomer (a2), monomer (a1) has the property of improving film strength and reducing film solubility. Therefore, if the content of monomer (a1) is too little, the strength of the film is easily reduced, and the surface state of the film will deteriorate after a long time. On the other hand, if the content of monomer (a1) is too much, the solubility of the film becomes low, and the antifouling performance is sometimes reduced.

[0034] <Monomer (a1)>

[0035] The monomer (a1) is a compound of the general formula (1) wherein n is 1, and is represented by the general formula (2).

[0036] [Chemistry 2]

[0037]

[0038] In the general formula (2), R 1 ~R 3 The explanation of is the same as that of general formula (1).

[0039] Examples of the monomer (a1) include methoxycarbonylmethyl (meth)acrylate, ethoxycarbonylmethyl (meth)acrylate, isopropyloxycarbonylmethyl (meth)acrylate, n-propyloxycarbonylmethyl (meth)acrylate, n-butoxycarbonylmethyl (meth)acrylate, tert-butoxycarbonylmethyl (meth)acrylate, 2-ethylhexyloxycarbonylmethyl (meth)acrylate, cyclohexyloxycarbonyl methacrylate, benzyloxycarbonylmethyl (meth)acrylate, phenoxycarbonyl methacrylate, 2-methoxyethoxycarbonylmethyl (meth)acrylate, 4-methoxybutoxycarbonylmethyl (meth)acrylate, aryloxycarbonyl methacrylate, vinyloxycarbonylmethyl (meth)acrylate, 1-(methoxycarbonyl)methyl (meth)acrylate, and the like. )ethyl (meth)acrylate, 1-(ethoxycarbonyl)ethyl (meth)acrylate, 1-(n-propoxycarbonyl)ethyl (meth)acrylate, 1-(isopropoxycarbonyl)ethyl (meth)acrylate, 1-(n-butoxycarbonyl)ethyl (meth)acrylate, 1-(tert-butoxycarbonyl)ethyl (meth)acrylate, α-(methoxycarbonyl)benzyl (meth)acrylate, α-(ethoxycarbonyl)benzyl (meth)acrylate, and preferably methoxycarbonylmethyl (meth)acrylate, ethoxycarbonylmethyl (meth)acrylate, isopropoxycarbonylmethyl (meth)acrylate, n-propoxycarbonylmethyl (meth)acrylate, n-butoxycarbonylmethyl (meth)acrylate, 1-(methoxycarbonyl)ethyl (meth)acrylate, and 1-(ethoxycarbonyl)ethyl (meth)acrylate.

[0040] <Monomer (a2)>

[0041] The monomer (a2) is a compound represented by the general formula (1) wherein n is 2 or greater. From the viewpoint of long-term antifouling properties, n in the formula (1) is preferably 2 to 6.

[0042] As monomer (a2), it is preferred to contain both a compound in which n is 2 and a compound in which n is 3 or greater. Specifically, for example, the mass ratio (n(2) / n(2 to 10)) based on solid content is preferably 0.4 to 0.8, more preferably 0.5 to 0.7. In this case, the coating film dissolution tends to be continuous and stable. Specifically, this value is, for example, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, or 0.80, and may also be within a range between any two of the numerical values ​​exemplified here.

[0043] Examples of the monomer (a2) include methyl (meth)acrylate di(oxycarbonylmethyl), ethyl (meth)acrylate di(oxycarbonylmethyl), isopropyl (meth)bis(oxycarbonylmethyl)acrylate, n-propyl (meth)acrylate di(oxycarbonylmethyl), n-butyl (meth)bis(oxycarbonylmethyl)acrylate, tert-butyl (meth)bis(oxycarbonylmethyl)acrylate, 2-ethylhexyl (meth)bis(oxycarbonylmethyl)acrylate, (meth)cyclohexyldi(oxycarbonylmethyl)acrylate, benzyl di(oxycarbonylmethyl) (meth)acrylate, (meth)phenyldi(oxycarbonylmethyl)acrylate, 2-methoxyethyl (meth)bis(oxycarbonylmethyl)acrylate, and (meth)bis(oxycarbonylmethyl)acrylate. 4-methoxybutyl (meth)acrylate, allyl (meth)bis(oxycarbonylmeth)acrylate, vinyl (meth)acrylate bis(oxycarbonylmethyl), methyl (meth)acrylate bis[1-(oxypolycarbonyl)ethyl], ethyl (meth)acrylate bis[1-(oxypolycarbonyl)ethyl], n-propyl (meth)bis[1-(oxypolycarbonyl)ethyl]acrylate, isopropyl (meth)bis[1-(oxypolycarbonyl)ethyl]acrylate, n-butyl (meth)bis[1-(oxypolycarbonyl)ethyl]acrylate, tert-butyl (meth)acrylate bis[1-(oxypolycarbonyl)ethyl], methyl (meth)acrylate bis[α-(oxycarbonyl)benzyl], ethyl (meth)acrylate bis[α-(oxycarbonyl)benzyl],Preferred examples include methyl (meth)acrylate di(oxycarbonylmethyl), ethyl (meth)acrylate di(oxycarbonylmethyl), isopropyl (meth)acrylate di(oxycarbonylmethyl), n-propyl (meth)acrylate di(oxycarbonylmethyl), n-butyl (meth)acrylate di(oxycarbonylmethyl), methyl (meth)acrylate di[1-(oxypolycarbonylethyl)], ethyl (meth)acrylate di[1-(oxypolycarbonylethyl)], methyl (meth)acrylate poly(oxycarbonylmethyl), ethyl (meth)acrylate poly(oxycarbonylmethyl), poly(oxycarbonylmethyl) and poly(oxycarbonylethyl) are preferably mentioned. Isopropyl (meth)acrylate, n-propyl (meth)acrylate poly(oxycarbonylmethyl), n-butyl (meth)acrylate poly(oxycarbonylmethyl), tert-butyl (meth)acrylate poly(oxycarbonylmethyl), 2-ethylhexyl (meth)acrylate poly(oxycarbonylmethyl), cyclohexyl (meth)acrylate poly(oxycarbonylmethyl), benzyl (meth)polyoxycarbonylmethacrylate), phenyl (meth)poly(oxycarbonylmethyl)acrylate, 2-methoxyethyl (meth)acrylate poly(oxycarbonylmethyl), 4-methoxybutyl (meth)acrylate poly(oxycarbonylmethyl) Acrylates, allyl (meth)acrylate poly(oxycarbonylmethyl), vinyl (meth)acrylate poly(oxycarbonylmethyl), methyl (meth)acrylate poly[1-(oxypolycarbonyl)ethyl], ethyl (meth)acrylate poly[1-(oxypolycarbonyl)ethyl], (meth)n-propyl poly[1-(oxypolycarbonyl)ethyl]acrylate, (meth)isopropyl poly[1-(oxypolycarbonyl)ethyl]acrylate, n-butyl (meth)acrylate poly[1-(oxypolycarbonyl)ethyl], tert-butyl (meth)acrylate poly[1-(oxypolycarbonyl)ethyl], ( Methyl (meth)acrylate poly[α-(oxycarbonyl)benzyl], ethyl (meth)acrylate poly[α-(oxycarbonyl)benzyl], preferably methyl (meth)acrylate poly(oxycarbonylmethyl), ethyl (meth)acrylate poly(oxycarbonylmethyl), isopropyl (meth)poly(oxycarbonylmethyl)acrylate, n-propyl (meth)acrylate poly(oxycarbonylmethyl), n-butyl (meth)acrylate poly(oxycarbonylmethyl), methyl (meth)acrylate poly[1-(oxypolycarbonylethyl)], ethyl (meth)acrylate poly[1-(oxypolycarbonylethyl)], etc.

[0044] 1-1-2. Monomer (b)

[0045] Monomer (b) is an ethylenically unsaturated monomer other than monomer (a). Monomer (b) can be divided into monomer (b1) and monomer (b2). Monomer (b) used for polymerization of copolymer A includes one or both of monomer (b1) and monomer (b2).

[0046] <Monomer (b1)>

[0047] The monomer (b1) is represented by the general formula (3).

[0048] [Chemistry 3]

[0049]

[0050] Where R 4 is hydrogen or methyl, R 5 ~R 7 Each of the groups is the same or different and represents a branched alkyl group having 3 to 8 carbon atoms or a phenyl group.

[0051] The number of carbon atoms of the branched alkyl group is, for example, 3, 4, 5, 6, 7, or 8, and may be within the range between any two of the numerical values ​​exemplified herein. Examples of the branched alkyl group include isopropyl, isopropenyl, isobutyl, sec-butyl, tert-butyl, 1-ethylpropyl, 1-methylbutyl, 1-methylpentyl, 1,1-dimethylpropyl, 1,1-dimethylbutyl, tert-hexyl, cyclohexyl, 1,1-dimethylpentyl, 1-methylhexyl, 1,1-dimethylhexyl, 1-methylheptyl, 2-methylbutyl, 2-ethylbutyl, 2,2-dimethylpropyl, cyclohexylmethyl, 2-ethylhexyl, 2-propylpentyl, and 3-methylpentyl. As R 5 ~R 7 Preferably, they are the same or different and are isopropyl, isopropenyl, sec-butyl, tert-butyl, phenyl, or 2-ethylhexyl, and are particularly preferably isopropyl and 2-ethylhexyl.

[0052] Examples of the monomer (b1) include triisopropylsilyl (meth)acrylate, triisobutylsilyl (meth)acrylate, tri-sec-butylsilyl (meth)acrylate, triisopentylsilyl (meth)acrylate, triphenylsilyl methyl (meth)acrylate, diisopropylphenylsilyl (meth)acrylate, diisopropylisobutylsilyl (meth)acrylate, diisopropylsec-butylsilyl (meth)acrylate, diisopropylisopentylsilyl (meth)acrylate, isopropyldiisobutylsilyl (meth)acrylate, isopropyldisec-butylsilyl (meth)acrylate, and tert-butyldiisopentylsilyl (meth)acrylate. Silyl (meth)acrylates such as tert-butyldiisopentylsilyl (meth)acrylate, tert-butyldiphenylsilyl (meth)acrylate, diisopropylhexylsilyl (meth)acrylate, diisopropylcyclohexylsilyl (meth)acrylate, tricyclohexylsilyl (meth)acrylate, tri-1,1-dimethylpentylsilyl (meth)acrylate, tri-2,2-dimethylpropylsilyl (meth)acrylate, tricyclohexylmethylsilyl (meth)acrylate, diisopropylcyclohexylmethylsilyl (meth)acrylate, tri-2-ethylhexylsilyl (meth)acrylate, and tri-2-propylpentylsilyl (meth)acrylate are also included. These monomers (b1) can be used alone or in combination of two or more.

[0053] <Monomer (b2)>

[0054] Monomer (b2) is obtained by removing monomer (b1) from monomer (b). That is, monomer (b2) is a monomer not represented by any of formulas (1) to (3). Examples of monomer (b2) include (meth)acrylates other than those represented by general formulas (1) to (3), vinyl compounds, aromatic compounds, and dialkyl esters of dibasic acids. In this specification, (meth)acrylate refers to either acrylate or methacrylate.

[0055] Examples of the (meth)acrylates not represented by the general formulae (1) to (3) include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-methoxypropyl (meth)acrylate, 4-methoxybutyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, (meth)propylene glycol monomethacrylate, 2-hydroxyethyl (meth)acrylate, (meth)propylene glycol monomethacrylate, (Meth)acrylic acid esters such as 2-hydroxypropyl (meth)acrylate, glycidyl (meth)acrylate, furfuryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, 2-[2-(2-hydroxyethoxy)ethoxy]ethoxy]ethyl methacrylate, mono(2-(meth)acryloyloxyethyl) succinate, N-(3-dimethylaminopropyl) (meth)acrylamide, 2-hydroxyethyl (meth)acrylate, 2-[2-(2-methoxyethoxy)ethoxy]ethyl (meth)acrylate, and N,N'-dimethyl (meth)acrylamide.

[0056] Examples of the vinyl compound include vinyl compounds having a functional group, such as vinyl chloride, vinylidene chloride, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl benzoate, vinyl butyrate, butyl vinyl ether, lauryl vinyl ether, and N-vinyl pyrrolidone.

[0057] Examples of the aromatic compound include styrene, vinyltoluene, and α-methylstyrene.

[0058] Examples of the dialkyl ester compound of a dibasic acid include dimethyl maleate, dibutyl maleate, and dimethyl fumarate.

[0059] In copolymer A, these monomers (b) can be used alone or in combination of two or more. From the viewpoint of coating film solubility and coating film properties, monomer (b) preferably contains a (meth)acrylate of monomer (b1) or monomer (b2). From the viewpoint of crack resistance, monomer (b) preferably contains a (meth)acrylate of monomer (b2), more preferably methyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, glycidyl (meth)acrylate, furfuryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, etc. From the viewpoint of coating film solubility, the monomer (b) preferably contains the monomer (b1), and more preferably contains triisopropylsilyl (meth)acrylate, tert-butyldiphenylsilyl (meth)acrylate, tri-2-ethylhexylsilyl (meth)acrylate, or the like.

[0060] 1-1-3. Physical Properties and Production Method of Copolymer A

[0061] The weight-average molecular weight (Mw) of copolymer A is preferably 5,000 to 25,000. If the molecular weight is less than 5,000, the antifouling coating film becomes brittle and easily peels or cracks. On the other hand, if it exceeds 25,000, when the amount of volatile organic compounds (VOCs) contained in the antifouling coating composition is low, the coating viscosity increases, making handling difficult. Specifically, the Mw is, for example, 5,000, 7,500, 10,000, 12,500, 15,000, 17,500, 20,000, 22,500, or 25,000, and may also be within a range between any two of the values ​​exemplified here.

[0062] As a method for measuring Mw, gel permeation chromatography (GPC method) can be mentioned.

[0063] Copolymer A may be a random copolymer, an alternating copolymer, a periodic copolymer or a block copolymer of monomer (a) and monomer (b).

[0064] The copolymer A can be obtained, for example, by polymerizing the monomer (a) and the monomer (b) in the presence of a polymerization initiator.

[0065] Examples of the polymerization initiator include azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2'-azobisisobutyrate, dimethyl 2,2'-azobisisobutyrate, and 2,2'-azobis(N-butyl-2-methylpropionamide); benzoyl peroxide, di-tert-butyl peroxide, tert-butyl peroxybenzoate, and tert-butyl carbonate. Peroxides such as butyl isopropyl peroxide, t-butyl peroxy-2-ethylhexanoate, t-hexyl peroxy-2-ethylhexanoate, di-t-hexyl peroxide, t-butyl peroxide-2-ethylhexyl monocarbonate, di-t-butyl peroxide, 1,1,3,3-tetramethylbutyl peroxyneodecanoate, t-amyl peroxyneodecanoate, t-hexyl peroxypivalate, t-amyl peroxypivalate, and 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate can be used alone or in combination of two or more. Particularly preferred polymerization initiators include 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2'-azobisisobutyrate, and tetramethylbutyl 1,1,3,3-peroxy-2-ethylhexanoate. The molecular weight of the copolyester A can be adjusted by appropriately setting the amount of polymerization initiator used. Chain transfer agents can also be used to adjust the molecular weight of the resulting polymer. Examples of chain transfer agents include mercaptans such as n-dodecylmercaptan; thioglycolates such as octylthioglycolate; α-methylstyrene dimer; and terpinolene.

[0066] Examples of the polymerization method include solution polymerization, bulk polymerization, emulsion polymerization, suspension polymerization, and non-aqueous dispersion polymerization. Of these, solution polymerization or non-aqueous dispersion polymerization is particularly preferred from the perspective of obtaining copolymer A simply and accurately.

[0067] In the polymerization reaction, an organic solvent may be used as needed. The organic solvent is not particularly limited, and examples thereof include aromatic hydrocarbon solvents such as xylene and toluene; aliphatic hydrocarbon solvents; ester solvents such as ethyl acetate, butyl acetate, isobutyl acetate, methoxypropyl acetate, and propylene glycol 1-monomethyl ether 2-acetate; alcohol solvents such as isopropyl alcohol, butanol, and propylene glycol monomethyl ether; ether solvents such as dioxane, diethyl ether, and dibutyl ether; and ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone.

[0068] Among them, butyl acetate, isobutyl acetate, butanol, propylene glycol monomethyl ether, propylene glycol 1-monomethyl ether 2-acetate, toluene, and xylene are preferred. These solvents can be used alone or in combination of two or more.

[0069] The reaction temperature in the polymerization reaction can be appropriately set depending on the type of the polymerization initiator, and is usually 50 to 160°C, and preferably 60 to 150°C.

[0070] The polymerization reaction is preferably carried out under an inert gas atmosphere such as nitrogen or argon.

[0071] 1-2. Antifouling reagents

[0072] Examples of the antifouling agent include inorganic agents and organic agents.

[0073] Examples of the inorganic reagent include cuprous oxide, copper thiocyanate (common name: endosulfan copper), and copper powder. Among these, cuprous oxide and endosulfan copper are particularly preferred. From the perspective of long-term storage stability, cuprous oxide surface-treated with glycerol, sucrose, stearic acid, lauric acid, lecithin, mineral oil, or the like is more preferred.

[0074] Examples of the organic reagent include copper 2-pyridinethione-N-oxide (common name: copper pyrithione), zinc 2-pyridinethione-N-oxide (common name: zinc pyrithione), zinc ethylenebisdithiocarbamate (common name: Zineb), 4,5-dichloro-2-n-octyl-3-isothiazolone (common name: Sea Nine 211), 3,4-dichlorophenyl-NN-dimethylurea (common name: Diuron), 2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine (common name: Irgalol 1051), 2-(p-chlorophenyl)-3-cyano-4-bromo-5-trifluoromethylpyrrole (common name: Econea 28), and 4-[1-(2,3-dimethylphenyl)ethyl]-1H-imidazole (common name: Medetomidine).

[0075] These antifouling agents can be used alone or in combination of two or more.

[0076] The content of the antifouling agent in the composition of the present invention is not particularly limited, but is generally 0.1 to 60.0% by mass in terms of solid content. Examples of the antifouling agent content include 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, and 60% by mass, and may also be within a range between any two of the values ​​exemplified herein.

[0077] 1-3. Volatile organic compounds (VOCs)

[0078] The antifouling coating composition of the present invention preferably has a VOC content of less than 400 g / L. In this case, the amount of VOC released into the environment during film formation is relatively low. The VOC content is, for example, 100 to 399 g / L, specifically 100, 150, 200, 250, 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, or 399 g / L, and may also be within a range between any two of these values.

[0079] VOC content is calculated using the following method. First, measure the volatile components (mass %) in the target sample according to ASTM D2369-07. Then, determine the specific gravity of the target sample at 25°C according to ASTM D1475-98. Using the calculated specific gravity, convert the volatile components (mass %) into g / L to calculate the VOC content.

[0080] Specifically, take 0.3 ± 0.1 g of the target sample, dilute it with 3 ± 1 ml of toluene, and dry it in a dryer at 110 ± 5°C for 1 hour. The volatile content (weight %) is calculated by weighing the sample before and after drying. The specific gravity can be determined using a pycnometer or pycnometer and measured at 25°C. Using these volatile contents and the specific gravity, the VOC (g / L) is calculated.

[0081] 1-4. Other additives

[0082] Furthermore, the antifouling coating resin of the present invention can be used as an antifouling coating by optionally adding resin components other than the copolymer A, dissolution regulators, plasticizers, pigments, dyes, defoamers, dehydrating agents, thixotropic agents, organic solvents, etc. as needed.

[0083] Other resin components include, for example, the following copolymer B and polymer P.

[0084] Copolymer B is a copolymer of monomer (b1) and monomer (b2), and contains monomer units derived from monomers (b1) and (b2). The content of monomer (b1) is preferably 10 to 90% by mass, more preferably 20 to 70% by mass, relative to the total of monomers (b1) and (b2). Specifically, for example, it may be 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, or 90% by mass, and may also be within a range between any two of the values ​​exemplified herein. In this case, the coating film solubility is particularly excellent.

[0085] The polymerization method, initiator, solvent, temperature, other conditions, Mw measurement method, etc. can be applied to the method for copolymer A described above.

[0086] The content of copolymer B in the composition of the present invention is not particularly limited, but the mass ratio (copolymer B / copolymer A) calculated as solid content relative to copolymer A is generally 0.1 to 0.9, preferably 0.3 to 0.7. This mass ratio is exemplified by 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9, and may be within a range between any two of the values ​​exemplified herein.

[0087] The polymer P is a polymer obtained by polymerizing the monomer (b2).

[0088] In the present invention, monomer (b2) can be used alone or in combination of two or more. In particular, from the viewpoint of compatibility with copolymer A, methyl (meth)acrylate and ethyl (meth)acrylate, preferred are methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, ethoxyethyl 2-(meth)acrylate, furfuryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, benzyl (meth)acrylate, and the like.

[0089] The polymerization method, initiator, solvent, temperature, other conditions, Mw measurement method, etc. can be applied to the method for copolymer A described above.

[0090] The content of polymer P in the composition of the present invention is not particularly limited, but the content ratio of polymer P to copolymer A, calculated as solid content, is generally 0.1 to 0.5, preferably 0.1 to 0.3 by mass (polymer P / copolymer A). This mass ratio is exemplified by 0.1, 0.2, 0.3, 0.4, or 0.5, and may also be within a range between any two of the values ​​exemplified herein.

[0091] Examples of dissolution modifiers include rosin, rosin derivatives, cycloalkanoic acid, cycloalkenyl carboxylic acid, bicycloalkenyl carboxylic acid, versatile carbonic acid, trimethylisobutenylcyclohexene carboxylic acid, and metal salts thereof, as well as monocarboxylic acids and salts thereof; or the aforementioned alicyclic hydrocarbon resins. These can be used alone or in combination of two or more.

[0092] Examples of the rosin derivatives include hydrogenated rosin, disproportionated rosin, maleated rosin, formylated rosin, and polymerized rosin.

[0093] Examples of the alicyclic hydrocarbon resin include commercially available products such as Quinton 1500, 1525L, and 1700 (trade names, manufactured by Zeon Corporation of Japan).

[0094] Among them, rosin, rosin derivatives, cyclohexane acid, versatile carbonic acid, trimethylisobutenylcyclohexenecarboxylic acid, or metal salts thereof are preferred.

[0095] Examples of the plasticizer include phosphates, phthalates, adipates, sebacates, polyesters, epoxidized soybean oil, alkyl vinyl ether polymers, polyalkylene glycols, tert-nonyl pentasulfide, vaseline, polybutene, tri(2-ethylhexyl) trimellitate, silicone oil, and chlorinated paraffin. These can be used alone or in combination of two or more.

[0096] Examples of the dehydrating agent include calcium sulfate, synthetic zeolite adsorbents, orthoesters, silicates such as tetramethoxysilane and tetraethoxysilane, isocyanates, carbodiimides, and carbondiimidazoles, etc. These can be used alone or in combination of two or more.

[0097] 2. Physical properties of antifouling coating compositions

[0098] The viscosity of the antifouling coating composition of the present invention at 25°C is preferably 80 to 110 KU. This facilitates handling of the antifouling coating composition and minimizes prolonged drying time during film formation. Specifically, the viscosity is, for example, 80, 85, 90, 95, 100, 105, or 110 KU, but may also be within a range between any two of these values. The viscosity can be measured by the method described in the Examples.

[0099] 3. Method for producing antifouling coating composition

[0100] The antifouling coating composition of the present invention can be produced by, for example, mixing and dispersing a mixed solution containing the copolymer A, the antifouling agent, other additives, etc. using a disperser.

[0101] The mixed liquid is preferably prepared by dissolving or dispersing various materials such as the copolymer A and the antifouling agent in a solvent.

[0102] As the dispersing machine, for example, a dispersing machine that can be used as a fine pulverizer can be appropriately used. For example, a commercially available homogenizer, sand mill, bead mill, dispersing machine, etc. can be used. Alternatively, the mixed liquid can be mixed and dispersed using a container equipped with an agitator and glass beads or the like added thereto for mixing and dispersing.

[0103] The antifouling coating composition is preferably prepared by mixing a solution of copolymer A with an antifouling agent and / or other additives. In this case, the solution of copolymer A preferably has a solids content of 55% by mass or greater. A high solids content in the copolymer A solution reduces the amount of solvent contained in the copolymer A solution, thereby reducing the VOC content of the antifouling coating composition prepared using the solution. The solids content is, for example, 55 to 90% by mass, preferably 55 to 70% by mass, and specifically, for example, 55, 60, 65, 70, 75, 80, 85, or 90% by mass, preferably within a range between any two of the given values.

[0104] Furthermore, when the antifouling agent and / or additive has poor dispersibility or solubility, the antifouling agent and / or additive can be pre-dispersed or dissolved using an additional solvent to form a first liquid, preferably by mixing the first liquid with the copolymer A solution. This can improve dispersibility and / or solubility. When the VOC content in the antifouling coating composition is set below a specified value, the amount of solvent available for pre-dispersion or dissolution depends on the amount of solvent contained in the copolymer A solution. Therefore, by increasing the solid content of the copolymer A solution, the amount of solvent available for pre-dispersion or dissolution can be increased.

[0105] 4. Antifouling treatment methods, antifouling coatings, and coatings

[0106] In the antifouling treatment method of the present invention, an antifouling coating film is formed on the surface of an object to be coated using an antifouling coating composition. According to the antifouling treatment method of the present invention, the antifouling coating film gradually dissolves from the surface, and the coating film surface is continuously renewed, thereby preventing the adhesion of aquatic fouling organisms.

[0107] Examples of the object to be coated include ships (particularly ship bottoms), fishing gear, and underwater structures.

[0108] The thickness of the antifouling coating can be appropriately set depending on the type of the coating object, the ship's sailing speed, the seawater temperature, etc. For example, when the coating object is a ship bottom, the thickness of the antifouling coating is generally 50 to 700 μm, preferably 100 to 600 μm.

[0109] [Example]

[0110] The features of the present invention will be further clarified with reference to the following examples, etc. However, the present invention is not limited to the examples, etc.

[0111] % in each of the preparation examples, examples, and comparative examples represents mass %. The weight average molecular weight (Mw) is a value measured by GPC (polystyrene equivalent value). The GPC conditions are as follows.

[0112] Equipment: HLC-8220GPC manufactured by Tosoh Corporation

[0113] Chromatographic columns: TSKgelSuperHZM-M 2

[0114] Flow rate: 0.35 mL / min

[0115] Detector: RI

[0116] Column thermostat temperature: 40°C

[0117] Eluent: THF

[0118] The heating residual content is a value measured in accordance with JIS K 5601-1-2: 1999 (ISO 3251: 1993) "Test methods for coating components - Heating residual content".

[0119] The viscosity of the coating composition is a value measured at 25° C. using a Stormer viscometer in accordance with JIS K 5400, and the measurement conditions are as follows.

[0120] Stormer Viscometer: Stormer Viscometer No. 453 manufactured by Coating Tester Industries

[0121] Measurement temperature: 25±0.5℃

[0122] Sample volume: 500ml (add to the 500ml sample tank mark)

[0123] Weight: 75-1000g

[0124] Measurement method: Measure the time it takes for the rotor blade to rotate 100 times. By varying the weight, the 100-rotation time is determined by selecting the value closest to 30 seconds within the range of 27 to 33 seconds. The KU value is calculated using the KU conversion factor based on the number of seconds for 100 rotations and the mass of the weight used.

[0125] 1. Manufacturing Example

[0126] 1-1. Production Example of Monomer (a1)

[0127] <Production Example 1 (Production Example of Monomer a1-1)>

[0128] A four-necked flask equipped with a thermometer, condenser, stirrer, and dropping funnel was charged with 109 g (1.00 mol) of methyl chloroacetate, 72 g (1.00 mol) of acrylic acid, 0.1 g of 4-methoxyphenol, and 500 g of ethyl acetate. While stirring, 101 g (1.00 mol) of triethylamine was added dropwise while maintaining the temperature below 40°C. After the addition, the mixture was stirred at 70-80°C for 6 hours. After the reaction, the organic layer was washed sequentially with tap water, hydrochloric acid solution, and sodium bicarbonate solution, and then concentrated under reduced pressure to remove the solvent, yielding 129.7 g of monomer a1-1.

[0129] <Production Examples 2 to 7 (Production of Monomers a1-2 to a1-7)>

[0130] Using the raw materials shown in Table 1, monomers a1-2 to a1-7 were obtained by reaction in the same manner as in Production Example 1. The reaction conditions and yields of Production Examples 1 to 7 are shown in Table 1.

[0131] [Table 1]

[0132]

[0133] 1-2. Production Example of Monomer (a2)

[0134] <Production Example 8 (Production of Monomer a2-1)>

[0135] (First reaction)

[0136] To a four-necked flask equipped with a thermometer, condenser, and stirrer, 215 g (1.85 mol) of sodium monochloroacetate, 201 g (1.85 mol) of methyl chloroacetate, and 300 g of N-methyl-2-pyrrolidone were added, and the mixture was stirred at 70-80°C for 6 hours. After the reaction was completed, 500 ml of toluene was added to the reaction solution. The organic layer was washed sequentially with tap water, hydrochloric acid, and sodium bicarbonate, and then concentrated and distilled under reduced pressure to remove the solvent, yielding 262 g of methyloxycarbonyl chloroacetate monomer.

[0137] (Second reaction)

[0138] Next, a four-necked flask equipped with a thermometer, condenser, stirrer, and dropping funnel was charged with 200 g (1.20 mol) of methoxycarbonylmethyl chloroacetate (the product of the first reaction), 87 g (1.20 mol) of acrylic acid, 0.1 g of 4-methoxyphenol, and 500 g of ethyl acetate. While stirring, 122 g (1.20 mol) of triethylamine was added dropwise while maintaining the temperature below 40°C. After the addition was complete, the mixture was stirred at 70-80°C for 6 hours. After the reaction, the organic layer was washed sequentially with tap water, hydrochloric acid solution, and sodium bicarbonate solution, and then concentrated under reduced pressure to remove the solvent, yielding 230.6 g of monomer a2-1.

[0139] <Production Examples 9 to 42 (Production of Monomers a2-2 to a2-35)>

[0140] Using the raw materials shown in Tables 2 to 4, the monomers a2-2 to a2-35 shown in Table 2 were obtained by the same operation as in Production Example 8. Tables 2 to 4 show the reaction conditions and yields of Production Examples 8 to 42.

[0141] [Table 2]

[0142]

[0143] [Table 3]

[0144]

[0145] [Table 4]

[0146]

[0147] The raw materials in Tables 1 to 4 are detailed as follows.

[0148] AA: Acrylic acid

[0149] MAA: Methacrylic acid

[0150] NMP: N-methyl-2-pyrrolidone

[0151] CANa: sodium monochloroacetate

[0152] CPANa: sodium 2-chloropropionate

[0153] CAMe: methyl chloroacetate

[0154] CAEt: ethyl chloroacetate

[0155] CAiPr: isopropyl chloroacetate

[0156] CANBu: n-butyl chloroacetate

[0157] CPAMe: 2-chloropropionic acid methyl ester

[0158] MEHQ: 4-Methoxyphenol

[0159] TEA: triethylamine

[0160] 1-3. Example of Preparation of Copolymer Solution

[0161] <Production Example P1 (Production of Copolymer Solution A-1)>

[0162] A four-necked flask equipped with a thermometer, condenser, stirrer, and dropping funnel was charged with 40 g of xylene and 40 g of propylene glycol monomethyl ether as solvents, and nitrogen was introduced while stirring and maintaining the temperature at 88°C. Subsequently, monomers (a) and (b) in the amounts (g) shown in Table 5 and 3.0 g of 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (initial addition) as a polymerization initiator were added dropwise over 3 hours while maintaining the temperature at 88°C. After stirring at 88°C for 1 hour, 0.1 g of 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate was added three times every hour. The mixture was stirred at the same temperature for 2 hours, and then cooled to room temperature to obtain copolymer solution A-1. The heating residue and Mw of A-1 are shown in Table 5.

[0163] <Production Examples P2 to P28 (Production of Copolymer Solutions A-2 to A-23, B-1, and R-1 to R-4)>

[0164] Polymerization reactions were carried out in the same manner as in Preparation Example P1, except that the monomers, polymerization initiators, and solvents shown in Tables 5 to 8 were used. Copolymer solutions A-2 to A-23, B-1, and R-1 to R-4 were obtained. The heating residue and Mw of each polymer are shown in Tables 5 to 8. The values ​​for the raw material amounts in the tables are in g.

[0165] [Table 5]

[0166]

[0167] [Table 6]

[0168]

[0169] [Table 7]

[0170]

[0171] [Table 8]

[0172]

[0173] 1-4. Other manufacturing examples

[0174] <Production Example D1 (Production of Gum Rosin Solution)>

[0175] 300 g of Chinese gum rosin (WW) and 310 g of xylene were placed in a flask equipped with a thermometer, reflux condenser, and stirrer. The mixture was dehydrated under reduced pressure and reflux at 70-80°C for 1 hour to obtain a gum rosin xylene solution (brown transparent liquid, 50% solids). The heated residue of the resulting solution was 50.3%.

[0176] <Production Example D2 (Production of Hydrogenated Rosin Solution)>

[0177] A xylene solution of hydrogenated rosin (brown transparent liquid, solid content 50%) was obtained by the same method as in Production Example D1 except that the Chinese gum rosin (WW) in Production Example D1 was replaced with hydrogenated rosin. The heating residue of the obtained solution was 50.1%.

[0178] <Manufacturing Example D3 (Manufacturing of Gum Rosin Zinc Salt Solution)>

[0179] In a flask equipped with a thermometer, reflux condenser, and stirrer, 240 g of Chinese gum rosin (WW) and 360 g of xylene were added. Furthermore, 120 g of zinc oxide was added to convert all the resin acids in the rosin into rosin-type zinc salts. The mixture was then dehydrated under reduced pressure and reflux at 70-80°C for 3 hours. The solution was then cooled and filtered to obtain a xylene solution of gum rosin zinc salt (a dark brown, transparent liquid with a solids content of 50%). The resulting solution had a heating residue of 50.2%.

[0180] <Manufacturing Example D4 (Manufacturing of Hydrogenated Rosin Zinc Salt Solution)>

[0181] A xylene solution of hydrogenated rosin zinc salt (dark brown transparent liquid, solid content 50%) was obtained by the same method as in Production Example D3 except that Chinese gum rosin (WW) was replaced with hydrogenated rosin. The heating residue of the obtained solution was 50.5%.

[0182] 2. Examples 1 to 36 and Comparative Examples 1 to 4 (Production of Coating Compositions)

[0183] The components listed in Tables 9 to 13 were blended in the proportions (mass %) indicated in the tables and dispersed with glass beads having a diameter of 1.5 to 2.5 mm to prepare coating compositions. The VOC contents in the tables are values ​​measured using the method described in "1-3. Volatile Organic Compounds (VOC)."

[0184] [Table 9]

[0185]

[0186] [Table 10]

[0187]

[0188] [Table 11]

[0189]

[0190] [Table 12]

[0191]

[0192] [Table 13]

[0193]

[0194] Detailed information on each ingredient in the table is as follows.

[0195] <Dissolution Regulator>

[0196] Hydrogenated rosin zinc salt solution: the solution prepared in Preparation Example D4 was used

[0197] Gum rosin zinc salt solution: Use the solution prepared in Preparation Example D3

[0198] Gum rosin solution: Use the solution prepared in Preparation Example D1

[0199] Hydrogenated rosin solution: Use the solution prepared in Preparation Example D2

[0200] <Antifouling Reagent>

[0201] Cuprous oxide: Trade name "NC-301" (manufactured by Nissin Chemco Co., Ltd.)

[0202] Copper pyrithione: Trade name "Copper Omagin" (manufactured by LONZA Co., Ltd.)

[0203] SeaNine: Trade name "Sea Nine 211", 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (manufactured by R&H), 30% active ingredient solution in xylene

[0204] Zineb: [ethylene bis(dithiocarbamate)] zinc (manufactured by Ouchi Shinko Chemical Industry Co., Ltd.)

[0205] Zinc pyrithione: (manufactured by LONZA Co., Ltd.)

[0206] Econea028: Trade name "Econea028" 2-(p-chlorophenyl)-3-cyano-4-bromo-5-trifluoromethylpyrrole (manufactured by Janssen PMP)

[0207] Medetomidine: (±)-4-[1-(2,3-dimethylphenyl)ethyl]-1H-imidazole (manufactured by Wako Pure Chemical Industries, Ltd.)

[0208] <Pigment>

[0209] Iron Dan: Trade name "Bengara Kingyoku" (manufactured by Morishita Bengara Industry Co., Ltd.)

[0210] Talc: Trade name "Talc MS" (manufactured by Japan Talc Co., Ltd.)

[0211] Zinc oxide: Trade name "Zinc Oxide 2" (manufactured by Shodo Chemical Industry Co., Ltd.)

[0212] Titanium oxide: Trade name "FR-41" (manufactured by Furukawa Machinery & Metal Co., Ltd.)

[0213] <Other additives>

[0214] Disparlon A603-20X: Amide-based thixotropic agent: Trade name "Disparlon A603-20X" (manufactured by Kusumoto Chemicals Co., Ltd.)

[0215] Disparlon 4200-20: Polyethylene oxide thixotropic agent: Trade name "Disparlon 4200-20" (manufactured by Kusumoto Chemicals Co., Ltd.)

[0216] Tetraethoxysilane: Trade name "ethyl silicate 28" (manufactured by Colcoat Co., Ltd.)

[0217] Tricresyl phosphate: (manufactured by Daihachi Chemical Industry Co., Ltd.)

[0218] Chlorinated paraffin: Trade name "Paraffin Chlorlated (Cl: 40%)" (manufactured by Wako Pure Chemical Industries, Ltd.)

[0219] 3. Experiment

[0220] The coating compositions of Examples and Comparative Examples were subjected to the following tests. The evaluation results are shown in Tables 9 to 13.

[0221] All the comparative examples did not show good results in the rotation test, antifouling test, or even the coating film drying test compared to the examples.

[0222] <Test Example 1 (Rotation Test)>

[0223] A rotating drum with a diameter of 515mm and a height of 440mm is installed in the center of the water tank and rotated by an electric motor. A cooling device is also installed to maintain a constant seawater temperature, and an automatic pH controller is installed to maintain a constant pH value.

[0224] The test panels were prepared as follows.

[0225] First, a rust-proof coating (epoxy-based A / C) was applied to a titanium plate (71 × 100 × 0.5 mm) to a dry thickness of approximately 100 μm, and dried to form a rust-proof coating film. Subsequently, the coating compositions obtained in Examples and Comparative Examples were applied to a dry film thickness of approximately 300 μm, and dried at 40°C for 3 days to prepare a test plate.

[0226] The prepared test plate was fixed to the drum of the rotating device of the apparatus so as to contact the seawater, and the drum was rotated at a speed of 20 knots. During this period, the seawater temperature was maintained at 25°C and the pH value was maintained at 8.0-8.2. The seawater was replaced every two weeks.

[0227] The residual film thickness of each test plate was measured at the initial stage and every six months after the start of the test using a shape measurement laser microscope VK-X100 manufactured by Keyence Corporation. The dissolved film thickness was calculated from the difference between the two values ​​to determine the amount of film dissolved per month (μm / month). In addition, when measuring the residual film thickness 24 months after the rotation test, the surface condition of each coating film was evaluated by visually observing the surface of each coating film with a microscope.

[0228] The coating film surface condition was evaluated according to the following criteria.

[0229] ◎: When there is no abnormality at all

[0230] ○: Hairy cracks are visible on less than 10% of the total surface area of ​​the coating

[0231] △: Hairy cracks are visible on 10-30% of the total surface area of ​​the coating

[0232] ×: Hairy cracks are visible on more than 30% of the total surface area of ​​the coating

[0233] XX: Abnormalities in the coating film such as large cracks, blistering, flaking (flaking only on the coating film surface or part of the edge), and peeling (flaking of the entire coating film with no residue left in the test coating film) are visible.

[0234] <Test Example 2 (Antifouling Test)>

[0235] The coating compositions obtained in the Examples and Comparative Examples were applied to both sides of rigid PVC panels (100 × 200 × 2 mm) to a dry coating thickness of approximately 300 μm. The resulting coatings were dried at room temperature (25°C) for three days to produce test panels having a dry coating thickness of approximately 300 μm. These panels were immersed 1.5 m below the sea level in Owase City, Mie Prefecture, and the panels were observed for contamination caused by adhering matter after 12 and 24 months.

[0236] Evaluation was performed by visually observing the state of the coating film surface and judging according to the following criteria.

[0237] ◎: No fouling organisms such as shellfish and algae are attached, and there is almost no slime.

[0238] ○: There is no fouling organism such as shellfish or algae attached, and there is thin slime attached (to the extent that the coating surface is visible), which can be removed by gently wiping with a brush.

[0239] △: Although no fouling organisms such as shellfish or algae are attached, the coating surface is so thick that the slime is barely visible and cannot be removed even by rubbing vigorously with a brush.

[0240] ×: Level of fouling organisms such as shellfish and algae attached

[0241] <Test Example 3 (Coating Drying Test)>

[0242] On a steel plate coated with anti-rust paint, a 120μm epoxy-based tie coat was applied as a dry film and dried. Then, a 150μm dry film thickness of the prepared antifouling paint was applied on top. This process was repeated twice, followed by drying for one day, to prepare a test plate with a dry film thickness of 300μm. This test plate was dried at room temperature for one or two days. A 30mm×30mm×10mm simulated plate was placed on the coating surface and a 40kgf / cm2 pressure was applied perpendicular to the coating. 2 The coating was applied with a pressure of 100°C for 20 minutes, and the surface condition of the coating after the simulated wood block was removed was observed. Evaluation was performed based on the following criteria. Poor drying properties of the antifouling coating significantly deformed the coating when the simulated wood block was removed, making this undesirable. Comparative Examples 1 to 4 exhibited poor drying properties, resulting in deformation of the coating, making them undesirable.

[0243] ○: A wood-coated mark was observed.

[0244] Δ: The periphery of the wood block was deformed, and swelling of the coating film was observed.

[0245] ×: The periphery of the wood panel was greatly deformed, and large swelling of the coating film was observed.

Claims

1. An antifouling coating composition comprising copolymer A and an antifouling agent, The copolymer A is a copolymer of a monomer (a) represented by the general formula (1) and an ethylenically unsaturated monomer (b) other than the monomer (a), wherein the monomer (a) contains a monomer (a1) in which n in the general formula (1) is 1 and a monomer (a2) in which n in the general formula (1) is 2 or more, and the content of the monomer (a1) in the monomer (a) is 50% by mass to 80% by mass. The weight average molecular weight of the copolymer A is 5,000 to 25,000, [Chemistry 1] （1） Where R 1 represents hydrogen or methyl, R 2 represents hydrogen, methyl or phenyl, R 3 represents an alkyl group or phenyl group having 1 to 8 carbon atoms which may be substituted with an alkoxy group or phenyl group having 1 to 8 carbon atoms, wherein n is an integer of 1 to 10, The content of volatile organic compounds in the antifouling coating composition is less than 400 g / L, and the viscosity of the antifouling coating composition at 25° C. is 80-110 KU.

Images