Antifouling coating composition

Abstract

Provided is an antifouling coating composition capable of maintaining coating film surface smoothness in seawater and maintaining antifouling performance.　According to the present invention, provided is an antifouling coating composition that contains a copolymer A, wherein the copolymer A is a copolymer of a monomer (a) represented by general formula (1) and an ethylenically unsaturated monomer (b) other than the monomer (a), the monomer (a) contains a compound in which n in general formula (1) is 2 or greater, and the monomer (b) contains a monomer (b1) represented by general formula (2) or general formula (3).

Description

Antifouling paint composition

[0001] This invention relates to an antifouling coating composition.

[0002] Aquatic fouling organisms such as barnacles, seldomegna, mussels, bryozoans, sea squirts, green laver, sea lettuce, and slime can attach to ships (especially the hulls), fishing nets, fishing net attachments, and underwater structures such as power plant water pipes, causing problems such as impaired functionality and damage to the appearance of these vessels.

[0003] To prevent such problems, there is a known technique for applying an antifouling paint composition to ships and other vessels to form an antifouling film, and then slowly releasing the antifouling agent from the film to provide long-term antifouling performance (Patent Documents 1-11). Silyl ester polymers have been widely used as typical binders for the aforementioned antifouling paint compositions, and various combinations with comonomers have been proposed. In particular, there have been proposals to use comonomers having an organopolysiloxane structure in order to improve the antifouling properties of the paint film (Patent Documents 1-10).

[0004] International Publication No. 2011 / 046087, International Publication No. 2018 / 088377, International Publication No. 2018 / 181429, JP 2019-199600, Patent No. 6472582, Patent No. 6499809, Patent No. 7324380, JP 2024-127280, Patent No. 6267411, International Publication No. 2018 / 181668, International Publication No. 2022 / 102492

[0005] However, although the antifouling coatings made from these antifouling paint compositions show some improvement in terms of coating solubility, the smoothness of the coating surface deteriorates drastically shortly after immersion in seawater, leading to a decrease in antifouling performance and resulting in reduced fuel efficiency. Furthermore, there are concerns about long-term problems with the physical properties of the coating, such as cracking.

[0006] This invention has been made in view of these circumstances, and provides an antifouling coating composition that can maintain the smoothness of the coating surface and maintain antifouling performance in seawater.

[0007] According to the present invention, an antifouling paint composition containing copolymer A is provided, wherein copolymer A is a copolymer of monomer (a) represented by general formula (1) and ethylenically unsaturated monomer (b) other than monomer (a), monomer (a) includes a compound in which n in general formula (1) is 2 or more, and monomer (b) includes monomer (b1) represented by general formula (2) or general formula (3).

[0008] The inventors conducted extensive research to solve the above problems and, as a result, discovered that a composition containing copolymer A can solve the above problems, thus completing the present invention. Furthermore, it was found that when the antifouling paint composition is colored with pigments or the like, it is possible to suppress color fading of the paint film.

[0009] The present invention will be described in detail below.

[0010] 1. Antifouling paint composition The antifouling paint composition of the present invention contains copolymer A.

[0011] 1-1. Copolymer A Copolymer A is a copolymer of monomer (a) and an ethylenically unsaturated monomer (b) other than monomer (a).

[0012] The content of monomer (a) relative to the total of monomer (a) and monomer (b) is preferably 10 to 90% by mass, and more preferably 20 to 70% by mass. Specifically, for example, these are 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, and 90% by mass, and may be within the range of any two of the values ​​exemplified here. In this case, it is particularly good from the viewpoint of maintaining the smoothness of the coating surface without causing discoloration of the coating surface.

[0013] The content of monomer (b1) relative to the total of monomer (a) and monomer (b) is preferably 0.1 to 50% by mass, and more preferably 1% to 40% by mass. Specifically, for example, these are 0.1, 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, and 50% by mass, and may be within the range of any two of the values ​​exemplified here. In this case, it is particularly good from the viewpoint of maintaining antifouling performance and the smoothness of the coating film surface.

[0014] 1-1-1. Monomer (a) Monomer (a) is represented by general formula (1).

[0015] In the formula, R １ R represents a hydrogen or methyl group. ２ R represents hydrogen, a methyl group, and a phenyl group. ３ is an alkyl group having 1 to 8 carbon atoms that may be substituted with an alkoxy group having 1 to 8 carbon atoms or a phenyl group, or a phenyl group, and n is an integer from 1 to 10.

[0016] R ２ Preferably, it is hydrogen or a methyl group.

[0017] R ３ The number of carbon atoms in the alkoxy group or alkyl group may be, for example, 1, 2, 3, 4, 5, 6, 7, or 8, and may be within the range of any two of the values ​​exemplified here. ３ For example, the group is a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, t-butyl group, 2-ethylhexyl group, cyclohexyl group, benzyl group, phenyl group, 2-methoxyethyl group, 4-methoxybutyl group, vinyl group, or allyl group, preferably a methyl group, ethyl group, isopropyl group, or n-butyl group.

[0018] n represents an integer between 1 and 10, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and may also be within the range of any two of the numbers exemplified here.

[0019] Monomer (a) contains a compound in which n is 2 or more in general formula (1). When monomer (a) contains a compound in which n is 2 or more, the coating film solubility is increased. Monomer (a) may consist only of compounds in which n is 2 or more, or it may be a mixture of a compound in which n is 1 and a compound in which n is 2 or more.

[0020] 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 to monomer (a2), monomer (a1) has the property of increasing the strength of the coating film and decreasing the solubility of the coating film. For this reason, if the content of monomer (a1) is too low, the strength of the coating film tends to be low, and the surface condition of the coating film may deteriorate after a long period of time. On the other hand, if the content of monomer (a1) is too high, the solubility of the coating film decreases, and the antifouling performance may decrease.

[0021] <Monomer (a1)> Monomer (a1) is a compound in which n in general formula (1) is 1. Examples of monomers (a1) include methoxycarbonylmethyl (meth)acrylate, ethoxycarbonylmethyl (meth)acrylate, isopropoxycarbonylmethyl (meth)acrylate, n-propoxycarbonylmethyl (meth)acrylate, n-butoxycarbonylmethyl (meth)acrylate, t-butoxycarbonylmethyl (meth)acrylate, 2-ethylhexyloxycarbonylmethyl (meth)acrylate, cyclohexyloxycarbonylmethyl (meth)acrylate, benzyloxycarbonylmethyl (meth)acrylate, phenoxycarbonylmethyl (meth)acrylate, 2-methoxyethoxycarbonylmethyl (meth)acrylate, 4-methoxybutoxycarbonylmethyl (meth)acrylate, allyloxycarbonylmethyl (meth)acrylate, vinyloxycarbonylmethyl (meth)acrylate, and 1-(methoxycarbonylmethyl (meth)acrylate. Examples include (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-(t-butoxycarbonyl)ethyl (meth)acrylate, α-(methoxycarbonyl)benzyl (meth)acrylate, and α-(ethoxycarbonyl)benzyl (meth)acrylate. Preferably, examples include 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.

[0022] <Monomer (a2)> Monomer (a2) is a compound in which n in general formula (1) is 2 or more. From the viewpoint of long-term stain resistance, n in general formula (1) is preferably 2 to 6.

[0023] The monomer (a2) preferably contains both a compound where n is 2 and a compound where n is 3 or more. Specifically, for example, in terms of solid content, the mass ratio (n(2) / n(2-10)) is preferably 0.4 to 0.8, and more preferably 0.5 to 0.7. In this case, a tendency for stable coating film dissolution to be sustained has been observed. Specifically, this value is, for example, 0.40, 0.45, 0.50, 0.55, 0.60, 0.65, 0.70, 0.75, 0.80, and may be within the range of any two of the values ​​exemplified here.

[0024] Examples of monomers (a2) 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), t-butyl (meth)acrylate di(oxycarbonylmethyl), 2-ethylhexyl (meth)acrylate di(oxycarbonylmethyl), and cyclohexyl (meth)acrylate di(oxycarbonyl Methyl, (meth)benzyl di(oxycarbonylmethyl), (meth)acrylate, phenyl di(oxycarbonylmethyl), (meth)acrylate, 2-methoxyethyl di(oxycarbonylmethyl), (meth)acrylate, 4-methoxybutyl di(oxycarbonylmethyl), (meth)acrylate, allyl di(oxycarbonylmethyl), (meth)acrylate, vinyl di(oxycarbonylmethyl), (meth)acrylate, methyl di[α-(oxycarbonyl)benzyl], (meth)acrylate, ethyl di[α-(oxycarbonyl)benzyl], (meth ) Methyl acrylate poly(oxycarbonylmethyl), (meth)ethyl acrylate poly(oxycarbonylmethyl), (meth)isopropyl acrylate poly(oxycarbonylmethyl), (meth)n-propyl acrylate poly(oxycarbonylmethyl), (meth)n-butyl acrylate poly(oxycarbonylmethyl), (meth)t-butyl acrylate poly(oxycarbonylmethyl), (meth)2-ethylhexyl acrylate poly(oxycarbonylmethyl), (meth)cyclohexyl acrylate poly(oxycarbonylmethyl), (meth) Examples include benzyl poly(oxycarbonylmethyl)ylylate, phenyl poly(oxycarbonylmethyl)methacrylate, 2-methoxyethyl poly(oxycarbonylmethyl)methacrylate, 4-methoxybutyl poly(oxycarbonylmethyl)methacrylate, allyl poly(oxycarbonylmethyl)methacrylate, vinyl poly(oxycarbonylmethyl)methacrylate, methyl poly[α-(oxycarbonyl)benzyl]methacrylate, and ethyl poly[α-(oxycarbonyl)benzyl]methacrylate.

[0025] Preferred monomers (a2) include methyl (meth)acrylate poly(oxycarbonylmethyl), ethyl (meth)acrylate poly(oxycarbonylmethyl), isopropyl (meth)acrylate poly(oxycarbonylmethyl), n-propyl (meth)acrylate poly(oxycarbonylmethyl), and n-butyl (meth)acrylate poly(oxycarbonylmethyl).

[0026] 1-1-2. Monomer (b) Monomer (b) is an ethylenically unsaturated monomer other than monomer (a). Examples of monomer (b) include (meth)acrylic acid esters, vinyl compounds, aromatic compounds, and dialkyl ester compounds of dibasic acids. In this specification, (meth)acrylic acid ester means acrylic acid ester or methacrylic acid ester. Monomer (b) can be classified into monomer (b1) and monomer (b2), and monomer (b) used in the polymerization of copolymer A includes at least monomer (b1).

[0027] <Monomer (b1)> Monomer (b1) is one or more compounds selected from the compounds represented by general formula (2) or general formula (3). (In the formula, R 4 (wherein represents a hydrogen or methyl group, and functional group A represents an organic functional group containing a polyorganosiloxane having two or more structural units represented by the following formula (4).)

[0028] The organic functional group of general formula (2) may consist solely of polyorganosiloxane, or it may contain a group other than polyorganosiloxane. Examples of other groups include hydrocarbon groups. It is preferable that a divalent group (preferably a hydrocarbon group), such as an alkylene group or a polyether group, is provided at one end of the polyorganosiloxane. In this case, the oxygen atom to which functional group A is linked and the polyorganosiloxane are linked via the divalent group. The number of carbon atoms in the divalent group is, for example, 1 to 10, and preferably 1 to 5. It is preferable that a monovalent group (preferably a hydrocarbon group), such as an alkyl group, is provided at the other end of the polyorganosiloxane. The number of carbon atoms in the monovalent group is, for example, 1 to 10, and preferably 1 to 5.

[0029] The compound representing the general formula (2) of monomer (b1) may be a commercially available product. Examples of commercially available products include "X-22-2404" (methacryloyloxyalkyl modified organopolysiloxane, functional group equivalent: 420 g / mol) manufactured by Shin-Etsu Chemical Co., Ltd., "X-22-174ASX" (methacryloyloxyalkyl modified organopolysiloxane, functional group equivalent: 900 g / mol), "X-22-174BX" (methacryloyloxyalkyl modified organopolysiloxane, functional group equivalent: 2300 g / mol), "KF-2012" (methacryloyloxyalkyl modified organopolysiloxane, functional group equivalent: 4600 g / mol), and "X-22-2426" (methacryloyloxyalkyl modified organopolysiloxane) Examples include "FM-0711" (one-terminated methacryloyloxyalkyl modified organopolysiloxane, number average molecular weight: 1000), "FM-0721" (one-terminated methacryloyloxyalkyl modified organopolysiloxane, number average molecular weight: 5000), "FM-0725" (one-terminated methacryloyloxyalkyl modified organopolysiloxane, number average molecular weight: 10000), "AK-5" (one-terminated methacryloyloxyalkyl modified organopolysiloxane, number average molecular weight: 5000), and "AK-32" (one-terminated methacryloyloxyalkyl modified organopolysiloxane, number average molecular weight: 20000), all manufactured by Toagosei Co., Ltd., with a functional group equivalent weight of 12000 g / mol.

[0030] (In the formula, R 5 (wherein represents a hydrogen or methyl group, and functional group A represents an organic functional group containing a polyorganosiloxane having two or more structural units represented by the following formula (4).)

[0031] The organic functional group of the general formula (3) may be composed solely of polyorganosiloxane, or may contain polyorganosiloxane and another group. Examples of the other group include a hydrocarbon group. It is preferable that a divalent group such as an alkylene group or a polyether group (preferably a hydrocarbon group) is provided at one or both terminals of the polyorganosiloxane. In this case, the oxygen atom to which the functional group A is linked and the polyorganosiloxane are linked via the divalent group. The number of carbon atoms in the divalent group is, for example, 1 to 10, preferably 1 to 5.

[0032] A commercially available product may be used as the compound represented by the general formula (3) for the monomer (b1). Examples of the commercially available product include "X-22-164" (both-terminal methacryloyloxyalkyl-modified organopolysiloxane, functional group equivalent: 190 g / mol), "X-22-164AS" (both-terminal methacryloyloxyalkyl-modified organopolysiloxane, functional group equivalent: 450 g / mol), "X-22-164A" (both-terminal methacryloyloxyalkyl-modified organopolysiloxane, functional group equivalent: 860 g / mol), "X-22-164B" (both-terminal methacryloyloxyalkyl-modified organopolysiloxane, functional group equivalent: 1600 g / mol), "X-22-164C" (both-terminal methacryloyloxyalkyl-modified organopolysiloxane, functional group equivalent: 2400 g / mol), and "X-22-164E" (both-terminal methacryloyloxyalkyl-modified organopolysiloxane, functional group equivalent: 3900 g / mol) manufactured by Shin-Etsu Chemical Co., Ltd.; as well as "FM-7711" (both-terminal methacryloyloxyalkyl-modified organopolysiloxane, number average molecular weight: 1000), "FM-7721" (both-terminal methacryloyloxyalkyl-modified organopolysiloxane, number average molecular weight: 5000), and "FM-7725" (both-terminal methacryloyloxyalkyl-modified organopolysiloxane, number average molecular weight: 10000) manufactured by JNC Corporation, and the like.

[0033] (wherein R 6 , R 7 each represent hydrogen, a methyl group, an alkyl group, an alkoxy group, a phenyl group, a substituted phenyl group, a phenoxy group or a substituted phenoxy group)

[0034] R 6 , R 7 A methyl group is preferred as the component.

[0035] <Monomer (b2)> Monomer (b2) is obtained by removing monomer (b1) from monomer (b). Examples of (meth)acrylic acid esters that are monomer (b2) include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, t-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, propylene glycol monomethyl (meth)acrylate, and (meth)acrylic acid. 2-Hydroxyethyl methacrylate, 2-Hydroxypropyl methacrylate, glycidyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, 2-[2-(2-hydroxyethoxy)ethoxy]ethoxy]ethyl methacrylate, mono(2-(meth)acryloyloxyethyl) succinate, N-(3-dimethylaminopropyl)(meth)acrylamide, 2-Hydroxyethyl methacrylate, 2-[2-(2-methoxyethoxy)ethoxy]ethyl methacrylate, N,N'-dimethyl(meth)acrylamide, poly(ethylene oxide) mono(meth)acrylate, isobornyl (meth)acrylate, macromonomers having a methacryloyl group at one terminal and containing no silicon atom (in terms of commercial products, "45% AA-6, number average molecular weight 6000", "AA-6SR, number average molecular weight 6000", "AA-6, number average molecular weight 6000", "AS-6, number average molecular weight 6000", "AN-6S, number average molecular weight 6000", "AB-6, number average molecular weight 6000", "AW-6S, number average molecular weight 6000" manufactured by Toagosei Co., Ltd.), and other (meth)acrylic acid esters, 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, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,5-pentanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and other di(meth)acrylic acid esters.

[0036] Examples of the vinyl compound that is the monomer (b2) include vinyl compounds having a functional group such as vinyl chloride, vinylidene chloride, vinyl benzoate, vinyl butyrate, butyl vinyl ether, lauryl vinyl ether, and the like. Examples of the aromatic compound that is the monomer (b2) include styrene, vinyltoluene, α-methylstyrene and the like. Examples of the dialkyl ester compound of a dibasic acid that is the monomer (b2) include dibutyl maleate and the like.

[0037] 1-1-3. Physical properties and production method of Copolymer A The weight average molecular weight (Mw) of Copolymer A is preferably 5000 to 300000. This is because if the molecular weight is less than 5000, the coating film of the antifouling paint will be brittle, prone to peeling and cracking, and if it exceeds 300000, the viscosity of the polymer solution will increase, making handling difficult. This Mw is specifically, for example, 5000, 10000, 20000, 30000, 40000, 50000, 60000, 70000, 80000, 90000, 100000, 200000, 300000, and may be within a range between any two of the numerical values exemplified herein.

[0038] Examples of the method for measuring Mw include gel permeation chromatography (GPC method).

[0039] Copolymer A may be any of a random copolymer, alternating copolymer, periodic copolymer, or block copolymer of monomer (a1), monomer (a2), monomer (b1), and monomer (b2).

[0040] Copolymer A can be obtained, for example, by copolymerizing a monomer mixture containing monomer (a) and monomer (b1) (preferably monomer (a1), monomer (a2), monomer (b1), and monomer (b2)) in the presence of a polymerization initiator.

[0041] Examples of polymerization initiators include azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl-2,2'-azobisisobutyrate, and 2,2'-azobis(N-butyl-2-methylpropionamide); benzoyl peroxide, di-tert-butyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxyisopropyl carbonate, and t-butyl peroxy Examples of peroxides include C-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, di-t-hexylperoxide, t-butylperoxy-2-ethylhexylmonocarbonate, di-t-butylperoxide, 1,1,3,3-tetramethylbutylperoxyneodecanoate, t-amylperoxyneodecanoate, t-hexylperoxypivalate, t-amylperoxypivalate, and 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate. These polymerization initiators can be used individually or in combination of two or more. Particularly preferred polymerization initiators are 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2'-azobisisobutyrate, and 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate. The molecular weight of copolymer A can be adjusted by appropriately setting the amount of polymerization initiator used. In addition, a chain transfer agent can be used to adjust the molecular weight of the resulting polymer. Examples of chain transfer agents include mercaptans such as n-dodecyl mercaptan; thioglycolic acid esters such as octyl thioglycolate; α-methylstyrene dimer; and terpinolene.

[0042] Polymerization methods include, for example, solution polymerization, bulk polymerization, emulsion polymerization, suspension polymerization, and non-aqueous dispersion polymerization. Among these, solution polymerization or non-aqueous dispersion polymerization is particularly preferred because it allows for the simple and accurate acquisition of copolymer A.

[0043] In the polymerization reaction described above, organic solvents may be used as needed. The organic solvents are not particularly limited, but examples 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, butyl alcohol, 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. Among these, butyl acetate, isobutyl acetate, butyl alcohol, propylene glycol monomethyl ether, propylene glycol 1-monomethyl ether 2-acetate, toluene, and xylene are preferred. These solvents can be used individually or in combination of two or more. The reaction temperature in the polymerization reaction can be appropriately set according to the type of polymerization initiator, and is usually 50 to 160°C, preferably 60 to 150°C.

[0044] The polymerization reaction is preferably carried out under an inert gas atmosphere such as nitrogen gas or argon gas.

[0045] 1-2. Other Additives Furthermore, the resin for antifouling coatings of the present invention may be further modified as needed by adding resin components other than copolymer A, antifouling agents, elution modifiers, plasticizers, pigments, dyes, defoamers, dehydrators, thixotropes, organic solvents, etc., to produce an antifouling coating.

[0046] Examples of antifouling agents include inorganic and organic agents. Examples of inorganic agents include cuprous oxide, copper thiocyanate (common name: rhodane copper), and copper powder. Examples of organic agents include 2-mercaptopyridine-N-oxide copper (generic name: copper pyrithione), 2-mercaptopyridine-N-oxide zinc (generic name: zinc pyrithione), zinc ethylene bisdithiocarbamate (generic name: zineb), 4,5-dichloro-2-n-octyl-3-isothiazolon (generic name: C9 211), 3,4-dichlorophenyl-N-N-dimethylurea (generic name: diuron), 2-methylthio-4-t-butylamino-6-cyclopropylamino-s-triazine (generic name: irgarol 1051), 2-(p-chlorophenyl)-3-cyano-4-bromo-5-trifluoromethylpyrrole (generic name: Econea 28), and 4-[1-(2,3-dimethylphenyl)ethyl]-1H-imidazole (generic name: medetomidine). These antifouling agents can be used individually or in combination of two or more types.

[0047] Examples of elution modifiers include monocarboxylic acids and their salts, such as rosin, rosin derivatives, naphthenic acid, cycloalkenyl carboxylic acid, bicycloalkenyl carboxylic acid, versatic acid, trimethylisobutenylcyclohexenecarboxylic acid, and their metal salts, or the aforementioned alicyclic hydrocarbon resins. These can be used individually or in combination of two or more. Examples of rosin derivatives include hydrogenated rosin, disproportionated rosin, maleated rosin, formylated rosin, and polymerized rosin. Examples of commercially available alicyclic hydrocarbon resins include Quinton 1500, 1525L, and 1700 (trade names, manufactured by Nippon Zeon Co., Ltd.). Among these, rosin, rosin derivatives, naphthenic acid, versatic acid, trimethylisobutenylcyclohexenecarboxylic acid, or their metal salts are preferred.

[0048] Examples of plasticizers include phosphate esters such as tricresyl phosphate, trioctyl phosphate, and triphenyl phosphate; phthalate esters such as dibutyl phthalate and dioctyl phthalate; adipate esters such as dibutyl adipate and dioctyl adipate; sebacate esters such as dibutyl sebacate and dioctyl sebacate; epoxidized oils and fats such as epoxidized soybean oil and epoxidized linseed oil; alkyl vinyl ether polymers such as methyl vinyl ether polymer and ethyl vinyl ether polymer; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; t-nonylpentasulfide; petrolatum; polybutene; tris(2-ethylhexyl) trimellitate; silicone oil; liquid paraffin; and chlorinated paraffin. These can be used individually or in combination of two or more.

[0049] Examples of silicone oils include polydimethylsiloxane, polymethylphenylsiloxane, methylphenylsiloxane-dimethylsiloxane copolymer, polyether-modified polydimethylsiloxane, polyether-modified polyalkyl(methyl)siloxane, polyester-modified polydimethylsiloxane, long-chain alkyl-modified polydimethylsiloxane, aralkyl-modified polydimethylsiloxane, polyether-long-chain alkylaralkyl-modified dimethylsiloxane oil, fluorosiloxane oil, amino-modified silicone oil, and other silicone oils modified with various functional groups.

[0050] Examples of pigments include red iron oxide, talc, titanium dioxide, silica, calcium carbonate, barium sulfate, and calcium oxide, and they can be used by adding one or more of these.

[0051] Examples of defoaming agents include silicone resin-based defoaming agents and acrylic resin-based defoaming agents.

[0052] Examples of thixotropes include bentonite, fatty acid amide wax, polyethylene oxide, and various amide compounds. These can be used individually or in combination of two or more.

[0053] Examples of organic solvents include aliphatic solvents, aromatic solvents, ketone solvents, ester solvents, and ether solvents, which are commonly used in antifouling coatings. These can be used individually or in combination of two or more.

[0054] Examples of dehydrating agents include calcium sulfate, synthetic zeolite-based adsorbents, orthoesters, silicates such as tetramethoxysilane and tetraethoxysilane, isocyanates, carbodiimides, and carbodiimidazoles. These can be used individually or in combination of two or more.

[0055] 2. Method for Producing the Antifouling Coating Composition The antifouling coating composition of the present invention can be produced by mixing and dispersing a mixed liquid containing, for example, copolymer A and other additives using a disperser. The mixed liquid is preferably a mixture in which various materials such as copolymer A are dissolved or dispersed in a solvent. The disperser can preferably be one that can be used as a fine grinder. For example, commercially available homomixers, sand mills, bead mills, dispersers, etc., can be used. Alternatively, the mixed liquid may be mixed and dispersed using a container equipped with a stirrer and containing glass beads for mixing and dispersion.

[0056] 3. Antifouling treatment method, antifouling coating, and coated object The antifouling treatment method of the present invention forms an antifouling coating on the surface of an object to be coated using the above-mentioned antifouling paint composition. According to the antifouling treatment method of the present invention, the antifouling coating gradually dissolves from the surface and the coating surface is constantly renewed, thereby preventing the adhesion of aquatic fouling organisms. Examples of objects to be coated include ships (especially the bottom of the ship), fishing gear, underwater structures, etc. The thickness of the antifouling coating can be appropriately set according to the type of object to be coated, the ship's cruising speed, seawater temperature, etc. For example, when the object to be coated is the bottom of a ship, the thickness of the antifouling coating is usually 50 to 700 μm, preferably 100 to 600 μm.

[0057] The following examples illustrate the features of the present invention. However, the present invention is not limited to these examples. Percentages in each manufacturing example, example, and comparative example indicate mass percentages. The weight-average molecular weight (Mw) is the value obtained by GPC (polystyrene equivalent). The GPC conditions are as follows: Apparatus: HLC-8220GPC manufactured by Tosoh Corporation Column: TSKgel SuperHZM-M 2 columns Flow rate: 0.35 mL / min Detector: RI Column constant temperature bath temperature: 40°C Eluent: THF The heat residue was measured in accordance with JIS K 5601-1-2:1999 (ISO 3251:1993) "Test method for paint components - Heat residue".

[0058] 1. Production Examples 1-1. Production Example of Monomer (a1) <Production Example 1 (Production of Monomer a1-1)> In a four-necked flask equipped with a thermometer, condenser, stirrer and dropping funnel, 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 were charged, and 101 g (1.00 mol) of triethylamine was added dropwise while stirring, 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 was complete, the organic layer was washed with tap water, hydrochloric acid solution, and sodium bicarbonate solution in that order, and then the solvent was removed by distillation under reduced pressure to obtain monomer a1-1: 129.7 g.

[0059] <Production Examples 2-3 (Production of Monomers a1-2 to a1-3)> Monomers a1-2 to a1-3 were obtained by carrying out the reaction using the raw materials shown in Table 1 in the same procedure as in Production Example 1. The reaction conditions and yields for Production Examples 1-3 are shown in Table 1.

[0060]

[0061] 1-2. Example of Monomer (a2) Production Example 4 (Production of Monomer a2-1) (First Reaction) In 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 charged and stirred at 70-80°C for 6 hours. After the reaction was complete, 500 ml of toluene was charged into the reaction solution, and the organic layer was washed in the order of tap water, hydrochloric acid solution, and sodium bicarbonate solution. The solvent was then removed by distillation under reduced pressure to obtain 262 g of methoxycarbonylmethyl chloroacetate.

[0062] (Second reaction) Next, in a four-necked flask equipped with a thermometer, condenser, stirrer, and dropping funnel, the products of the first reaction—methoxycarbonylmethyl chloroacetate: 200 g (1.20 mol), acrylic acid: 87 g (1.20 mol), 4-methoxyphenol: 0.1 g, and ethyl acetate: 500 g—were charged, and 122 g (1.20 mol) of triethylamine was added dropwise while stirring, 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 was complete, the organic layer was washed with tap water, hydrochloric acid solution, and sodium bicarbonate solution in that order, and the solvent was removed by distillation under reduced pressure to obtain monomer a2-1: 230.6 g.

[0063] <Production Examples 5-18 (Production of Monomers a2-2 to a2-15)> By carrying out the reaction using the raw materials shown in Table 2 in the same procedure as in Production Example 4, monomers a2-2 to a2-15 shown in Table 2 were obtained. The reaction conditions and yields for Production Examples 4-18 are shown in Table 2.

[0064]

[0065] Details of the raw materials in Tables 1 and 2 are as follows: CAMe: Methyl chloroacetate CAEt: Ethyl chloroacetate AA: Acrylic acid MAA: Methacrylic acid TEA: Triethylamine MEHQ: 4-Methoxyphenol CANa: Sodium monochloroacetate NMP: N-methyl-2-pyrrolidone

[0066] 1-3. Examples of Copolymer Solution Preparation <Preparation Example A1 (Preparation of Copolymer Solution A-1)> In a glass container, the solvent in the amounts (g) shown in Tables 3 and 4, monomer (a), monomer (b1), monomer (b2), and 2.0 g of 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate as a polymerization initiator were thoroughly mixed. Half of this mixture was added to a four-necked flask equipped with a thermometer, condenser, stirrer, and dropping funnel, and the remaining half was added to the dropping funnel. Nitrogen gas was then introduced, and the temperature was maintained at 88±5°C while stirring. The mixture in the dropping funnel was then added dropwise over 1 hour while maintaining the temperature at 88±5°C. Subsequently, the mixture was stirred at 88±5°C for 1 hour, then 0.1 g of 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate was added three times at 1-hour intervals. The mixture was then stirred at the same temperature for another 2 hours, and finally cooled to room temperature to obtain copolymer solution A-1. The heating residue and Mw of A-1 are shown in Table 3.

[0067] <Production Examples A2-A20 and B1-B4 (Production of Copolymer Solutions A-2-A-20 and B-1-B-4)> Copolymer solutions A-2-A-20 and B-1-B-4 were obtained by carrying out the polymerization reaction in the same manner as in Production Example A1, except that the monomers, polymerization initiators, and solvents shown in Tables 3-6 were used. The heating residue and Mw of each polymer are shown in the same tables. The units of the raw material amounts in the tables are grams.

[0068]

[0069]

[0070]

[0071]

[0072] The details of the raw materials in the table are as follows: FM-0711: Organopolysiloxane modified with methacryloyloxyalkyl at one end, number average molecular weight: 1000, manufactured by JNC Co., Ltd. X-22-174ASX: Organopolysiloxane modified with methacryloyloxyalkyl at one end, functional group equivalent: 900 g / mol, manufactured by Shin-Etsu Chemical Co., Ltd. FM-0721: Organopolysiloxane modified with methacryloyloxyalkyl at one end, number average molecular weight: 5000, manufactured by JNC Co., Ltd. FM-0725: Organopolysiloxane modified with methacryloyloxyalkyl at one end, number average molecular weight: 10000, manufactured by JNC Co., Ltd. FM-7711: Organopolysiloxane modified with methacryloyloxyalkyl at both ends, number average molecular weight: 1000, manufactured by JNC Co., Ltd. FM-7721: Organopolysiloxane modified with methacryloyloxyalkyl at both ends, number average molecular weight: 5000, manufactured by JNC Corporation. FM-7725: Organopolysiloxane modified with methacryloyloxyalkyl at both ends, number average molecular weight: 10000, manufactured by JNC Corporation. AA-6: Macromonomer manufactured by Toagosei Co., Ltd., segment: methyl methacrylate, number average molecular weight: 6000.

[0073] 1-4. Other Manufacturing Examples <Manufacturing Example C1 (Production of Gum Rosin Solution)> 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, and reflux dehydration was carried out under reduced pressure at 70-80°C for 1 hour to obtain a gum rosin xylene solution (brown transparent liquid, solid content 50%). The heating residue of the obtained solution was 50.3%.

[0074] <Production Example C2 (Preparation of Gum Rosin Zinc Salt Solution)> In a flask equipped with a thermometer, reflux condenser, and stirrer, 240 g of Chinese gum rosin (WW) and 360 g of xylene were placed in the flask. Further, 120 g of zinc oxide was added so that all of the resin acid in the rosin would form a zinc salt, and reflux dehydration was carried out under reduced pressure at 70-80°C for 3 hours. After that, the solution was cooled and filtered to obtain a xylene solution of gum rosin zinc salt (dark brown transparent liquid, solid content 50%). The heating residue of the obtained solution was 50.2%.

[0075] <Production Example C3 (Preparation of Hydrogenated Rosin Zinc Salt Solution)> In a flask equipped with a thermometer, reflux condenser, and stirrer, 240 g of hydrogenated rosin from China and 360 g of xylene were placed in the flask. Further, 120 g of zinc oxide was added so that all of the resin acid in the rosin would form a zinc salt, and reflux dehydration was carried out under reduced pressure at 70-80°C for 3 hours. After that, the solution was cooled and filtered to obtain a xylene solution of gum rosin zinc salt (dark brown transparent liquid, solid content 50%). The heating residue of the obtained solution was 50.1%.

[0076] 2. Examples 1 to 22 and Comparative Examples 1 to 11 (Preparation of Paint Compositions) Paint compositions were prepared by mixing and dispersing the components shown in Tables 7 to 11 in the proportions (mass%) shown in the same tables with glass beads with a diameter of 1.5 to 2.5 mm.

[0077]

[0078]

[0079]

[0080]

[0081]

[0082] The details of the ingredients in the table are as follows:

[0083] <Other Resins> Copolymer Solution B-5: Resin with the component composition described in Production Example S1 synthesized by the method in Patent Document 1 (solids content adjusted to 45%) Copolymer Solution B-6: Resin with the component composition described in Production Example S1 synthesized by the method in Patent Document 9 (solids content adjusted to 45%) Copolymer Solution B-7: Resin with the component composition described in Production Example S1 synthesized by the method in Patent Document 5 (solids content adjusted to 45%) Copolymer Solution B-8: Resin with the component composition described in Example 8 (A-8) synthesized by the method in Patent Document 10 (solids content adjusted to 45%) Copolymer Solution B-9: Resin with the component composition described in Production Example S8 synthesized by the method in Patent Document 7 (solids content adjusted to 45%) Copolymer Solution B-10: Resin with the component composition described in Production Example S9 synthesized by the method in Patent Document 7 (solids content adjusted to 45%) Copolymer solution B-11: A resin with the component composition described in production example S10, synthesized by the method described in Patent Document 7 (solid content adjusted to 45%).

[0084] <Dissolution modifiers> Gum rosin solution: Use the one manufactured in manufacturing example C1. Gum rosin zinc solution: Use the one manufactured in manufacturing example C2. Hydrogenated rosin zinc solution: Use the one manufactured in manufacturing example C3.

[0085] <Pigments> Red iron oxide: Product name "Bengara Kingyoku" (manufactured by Morishita Bengara Kogyo Co., Ltd.) Talc: Product name "Talc MS" (manufactured by Nippon Talc Co., Ltd.) Zinc oxide: Product name "Zinc Oxide Type 2" (manufactured by Seido Kagaku Kogyo Co., Ltd.) Titanium dioxide: Product name "FR-41" (manufactured by Furukawa Machinery & Metal Co., Ltd.)

[0086] <Anti-fouling agents> Cuprous oxide: Product name "NC-301" (manufactured by Nisshin Chemco Co., Ltd.) Copper pyrithione: Product name "Copper Omazine" (manufactured by LONZA Co., Ltd.) SEANINE211: 30% solid content, manufactured by Dupont Econea28: manufactured by Janssen Medetomidine: Product name "Selectope", manufactured by I-tech

[0087] <Other Additives> Disparon A603-20X: Amid-type thixotropic agent: Product name "Disparon A603-20X" (manufactured by Kusumoto Kasei Co., Ltd.) Tetraethoxysilane: Product name "Ethyl Silicate 28" (manufactured by Colcoat Co., Ltd.) Tricresyl phosphate: Manufactured by Daihachi Chemical Industry Co., Ltd. KF-96-100CS: Silicone oil (manufactured by Shin-Etsu Chemical Co., Ltd.) KF-6020: Modified silicone oil (manufactured by Shin-Etsu Chemical Co., Ltd.)

[0088] 3. All paint compositions in the test examples and comparative examples were subjected to accelerated degradation treatment by being placed in a sealed container within one hour of manufacture and left to stand for 30 days in a constant temperature device set to 50°C. This accelerates the degradation of the paint composition, thereby shortening the period required for long-term performance evaluation of the paint composition. The paints that underwent the above treatment were subjected to the following tests. The results are shown in Tables 7 to 11.

[0089] In all embodiments, no discoloration of the coating film occurred during the two-month rotary test, and the smoothness of the coating film was maintained. Furthermore, the condition of the coating film and its antifouling properties were excellent after the four-month immersion test at the waterline.

[0090] On the other hand, in all comparative examples, at least one of the coating film smoothness after the rotary test and the antifouling properties after the waterline immersion test was worse than in the examples. More specifically, in all comparative examples except Comparative Example 7, the coating film smoothness after the rotary test was worse than in the examples, and in all comparative examples, the coating film condition and antifouling properties after the waterline immersion test were worse than in the examples. Furthermore, color fading occurred in Comparative Examples 1 to 3 and 5.

[0091] In the comparative examples other than Comparative Example 4, a coating film was formed using a coating composition containing a copolymer obtained by copolymerizing a monomer mixture that does not contain monomer (a). In Comparative Example 4, a coating film was formed using a coating composition containing a copolymer obtained by copolymerizing a monomer mixture that contains monomer (a) but does not contain monomer (b1). The fact that the evaluation results in all comparative examples were not good indicates that by using a coating composition containing a copolymer obtained by copolymerizing a monomer mixture containing monomer (a) and monomer (b1), it is possible to form a coating film that can maintain the smoothness of the coating film surface and maintain antifouling performance in seawater.

[0092] <Test Example 1 (Rotary Test)> A rotating drum with a diameter of 515 mm and a height of 440 mm was installed in the center of the water tank and made rotatable by a motor. In addition, a cooling device to maintain a constant seawater temperature and an automatic pH controller to maintain a constant seawater pH were installed.

[0093] Test plates were prepared according to the following method. First, a rust-preventive coating film was formed on a titanium plate (71 × 100 × 0.5 mm) by applying an anti-corrosion coating (epoxy vinyl A / C) to a dry thickness of approximately 100 μm and allowing it to dry. Then, the coating compositions obtained in the examples and comparative examples were applied to a dry film thickness of approximately 450 μm and dried at 40°C for 3 days to prepare the test plates. The prepared test plates were fixed to the rotating drum of the rotating device of the above apparatus so as to be in contact with seawater, and the rotating drum was rotated at a speed of 20 knots. During this time, the seawater temperature was maintained at 25°C and the pH at 8.0 to 8.2, and the seawater was replaced every two weeks.

[0094] For each test panel, the color fading and unevenness of the coating were checked after two months. The color fading was evaluated visually. Panels where the color of the coating appeared lighter compared to the color of the panel before the test were evaluated as "color fading present," and those where no color fading was observed were evaluated as "no color fading."

[0095] The surface texture was measured using a Keyence VK-X100 shape measuring laser microscope to determine the thickness of the thickest and thinnest parts of the coating film surface two months after the start of the test. The difference between the thickest and thinnest parts, known as the coating film texture difference, was calculated. A larger value indicates a rougher coating film surface, and the coating film smoothness was evaluated according to the following criteria: ◎ (Excellent): Coating film texture difference of 0 μm or more and less than 5 μm 〇 (Good): Coating film texture difference of 5 μm or more and less than 10 μm △ (Acceptable): Coating film texture difference of 10 μm or more and less than 20 μm × (Unacceptable): Coating film texture difference of 20 μm or more

[0096] <Test Example 2 (Draft Immersion Test)> The paint compositions obtained in the Examples and Comparative Examples were applied to both sides of a rigid PVC board (100 x 400 x 2 mm) to a dry film thickness of approximately 300 μm. The resulting coating was dried at room temperature (25°C) for 3 days to prepare a test board with a dry film thickness of approximately 300 μm. This test board was immersed 0.5 m below sea level in Owase City, Mie Prefecture for 4 months, and the condition of the paint film surface was visually observed to evaluate the paint film condition and antifouling properties according to the following criteria.

[0097] In typical immersion tests, the test plate is usually submerged to a depth of about 1.5 meters below the sea surface, at which point the test plate is constantly submerged. However, in the waterline immersion test in this example, the test plate is submerged at a relatively shallow depth of 0.5 meters below the sea surface. At this depth, the test plate is repeatedly brought up and down by the waves. This depth corresponds to the waterline, which is slightly below the waterline of a ship, and is a depth where paint deterioration, fouling, and biological adhesion are likely to occur. Therefore, this test is conducted under more severe conditions than a normal immersion test where the test plate is submerged to 1.5 meters below the sea surface.

[0098] • Coating condition ◎ (Excellent): No abnormalities at all ○ (Good): Hairline cracks partially visible on the coating surface △ (Acceptable): Hairline cracks visible throughout the coating surface × (Unacceptable): Cracks visible on the coating surface

[0099] ・Fouling resistance ◎ (Excellent): No fouling organisms such as shellfish or algae are attached, and there is almost no slime. 〇 (Good): No fouling organisms such as shellfish or algae are attached, and although there is a thin layer of slime (enough to allow the coating surface to be seen), it can be easily wiped off with a brush. △ (Acceptable): No fouling organisms such as shellfish or algae are attached, but there is a thick layer of slime that completely covers the coating surface and cannot be removed even with vigorous wiping with a brush. × (Poor): Fouling organisms such as shellfish or algae are attached. ×× (Inferior): Fouling organisms such as shellfish or algae are attached in overlapping layers.

Claims

1. An antifouling coating composition containing copolymer A, wherein the copolymer A is a copolymer of a monomer (a) represented by general formula (1) and an ethylenically unsaturated monomer (b) other than the monomer (a), the monomer (a) comprises a compound in which n in the general formula (1) is 2 or more, and the monomer (b) comprises a monomer (b1) represented by general formula (2) or general formula (3). Antifouling coating composition. (wherein, R １ represents hydrogen or a methyl group, R ２ represents hydrogen, a methyl group, or a phenyl group, R ３ is an alkyl group having 1 to 8 carbon atoms which may be substituted with an alkoxy group having 1 to 8 carbon atoms or a phenyl group, or represents a phenyl group, and n represents an integer of 1 to 10.) (wherein, R 4 represents hydrogen or a methyl group, and functional group A represents an organic functional group comprising a polyorganosiloxane having 2 or more structural units represented by the following formula (4).) (wherein, R 5 represents hydrogen or a methyl group, and functional group A represents an organic functional group comprising a polyorganosiloxane having 2 or more structural units represented by the following formula (4).) (wherein R 6 , R 7 each represent hydrogen, a methyl group, an alkyl group, an alkoxy group, a phenyl group, a substituted phenyl group, a phenoxy group, or a substituted phenoxy group)

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