AU2011327409A1 - Antifouling coating composition, and fishing net, fishing net gear, and underwater structure coated with antifouling coating composition - Google Patents

Abstract

Provided is an antifouling coating composition capable of exhibiting an antifouling effect for a long period of time even in ocean water containing highly active barnacles, serpula, and other animal species, as well as hydrozoans and other coelenterates. This antifouling coating composition comprises (A) copper glass containing divalent copper, (B) metal pyrithiones, and (C) titanium oxide, wherein the metal of the metal pyrithiones is copper or zinc; the composition further contains a spreading resin; the content of copper in the copper glass (A) is 24—40 mol%; the content of the copper glass (A), in terms of solid content, is 1—20 mass% of the solid content of the antifouling coating composition; the content of the metal pyrithiones (B), in terms of solid content, is 25—150 parts by mass per 100 parts by mass of the copper glass (A); and the content of the titanium oxide (C), in terms of solid content, is 50—300 parts by mass per 100 parts by mass of the copper glass (A).

Description

SPECIFICATION TITLE OF THE INVENTION: ANTIFOULING COATING COMPOSITION, AND FISHING NET, FISHING NET GEAR, AND UNDERWATER STRUCTURE COATED 5 WITH ANTIFOULING COATING COMPOSITION TECHNICAL FIELD [0001] The present invention relates to an antifouling coating composition for .0 preventing, over a long period, aquatic fouling organisms from attaching to fishing nets for cultivation or fixed nets, fishing net equipments used for the fishing nets such as float and rope (hereinafter, collectively referred to as fishing net-related substances), underwater structures such as coolant conduit raceway tubes in power plants, and relates to fishing net-related substances and [5 underwater structures with the antifouling coating composition applied thereon. BACKGROUND ART [0002] When fishing net-related substances and underwater structures are used ,0 without applying thereon an antifouling coating composition, various aquatic fouling organisms, such as seaweeds, barnacle, serpula, sea moss, mollusks and the like attach thereto, since they are placed in seawater for a long time. This would inhibit water from penetrating through the fishing nets, causing mass death of fish due to shortage of oxygen and outbreak of infectious disease. Then, 25 the fish cannot be shipped and result in heavy damage, In addition, if such organisms attach to the cultivation nets or to the fixed nets, the nets would become heavy. This would become problematic since the fish may swim away if the nets sink, and the nets itself may flow out, Therefore, frequent replacement 1.

of the nets would become necessary, and such maintenance would require large amount of labor and cost. [0003] In order to prevent these aquatic fouling organisms from attaching, various 5 antifouling coating compositions have been widely applied to the fishing net-related substances and to the underwater structures. Among the antifouling coating compositions, antifouling coating compositions containing copper-based chemical agents such as copper oxide (1}, copper glass, copper pyrithione and the like show a certain degree of effect to prevent shellfish such as tO mussels, barnacle and serpula from attaching, Therefore, they have been widely used. [0004] As an example of antifouling coating composition which show excellent effect against animals such as barnacles and serpula and coelenterates such as 15 hydrozan, a composition which is formulated with copper oxide (I) and a particular polyether modified silicone oil has been disclosed (Patent Document 1). In addition, an antifouling coating composition which is formulated with copper pyrithione in addition to the copper oxide (I) and the particular polyether modified silicone oil has also been disclosed (Patent Document 2). 20 [0005] However, since copper oxide (1) employed for these antifouling coating compositions is difficult to dissolve in water, they are difficult to ionize. Therefore, repellent effect against aquatic fouling organisms was not sufficient, and the antifouling effects of the antifouling coating compositions were not 25 sufficient. [00061 Here, an antifouling coating composition which employs monovalent copper-containing soluble copper glass in place of the copper oxide (1), and employs a metal pyrithione in combination, has been disclosed (Patent 2 Document 3). Although the amount of copper ion eluted from the monovalent copper-containing soluble copper glass employed in the antifouling coating composition is larger than that eluted from the copper oxide (I), such amount is still insufficient to exhibit sufficient repelling effect against aquatic fouling 5 organisms. Therefore, the market still remains unsatisfied. [0007] Furthermore, an antifouling coating composition which employs divalent copper-containing copper glass has also been disclosed (Patent Document 4). However, the repelling effect of such antifouling coating composition was still to insufficient. [00081 Therefore, there has been desired development of an antifouling coating composition which shows superior physical properties, possesses excellent workability when applying the coating composition to fishing nets, and exhibits 15 long-term antifouling effect in the sea area where animals such as barnacles and serpula, and coelenterates such as hydrozan show high activity PRIOR ART REFERENCE PATENT DOCUMENT 20 [0009] Patent Document 1: JP-A-Hei 8- 252533 Patent Document 2: JP-A- 2002 265849 Patent Document 3: JP-A- 2000-264804 Patent Document 4: JP-A- 2004-203774 25 SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION [0010] 3 The present invention has been made concerning the afore-mentioned problems, An object of the present invention is to provide an antifouling coating composition which can exhibit long-term antifouling effect in the sea area where animals such as barnacles and serpula, and coelenterates such as hydrozan 5 show high activity. MEANS FOR SOLVING THE PROBLEMS [0011] An aspect according to the present invention provides an antifouling coating 1o composition, including (A) divalent copper-containing copper glass, (B) a metal pyrithione and (C) titanium oxide, wherein the metal pyrithione contains copper or zinc as the metal, the antifouling coating composition further comprises a spreading resin, the copper glass (A) contains CuO by 25 to 40 % by mol, the content of the copper glass (A) by solid is 1 to 20 % by mass with respect to the 1.5 solids of the antifouling coating composition, the content of the metal pyrithione (B) by solid is 25 to 150 parts by mass with respect to 100 parts by mass of the copper glass (A), and the content of titanium oxide (C) by solid is 50 to 300 parts by mass with respect to 100 parts by mass of the copper glass (A). [0012] 20 The present inventors have conducted intensive research to develop an antifouling coating composition which exhibits long-term antifouling effect, and have found that when the antifouling coating composition contains three components of (A) divalent copper-containing copper glass, (B) a metal pyrithione, and (C) titanium oxide by a certain ratio, the antifouling coating 25 composition exhibits an extremely excellent long-term antifouling effect, and thus have accomplished the present invention. [0013] The mechanism on how the antifouling coating composition according to the present invention exhibits an excellent long-term antifouling effect remains 4 unclear, Here, in the experiments, antifouling coating compositions containing only the divalent copper-containing copper glass or antifouling coating compositions containing the divalent copper-containing copper glass and a metal pyrithione were not able to maintain the antifouling effect for a long time. 5 The antifouling coating compositions were able to exhibit an excellent long-term antifouling effect only when they contained all of the afore-mentioned three components. Since the active substance which provides the composition with the antifouling effect is the copper glass and the metal pyrithione, it is assumed that titanium oxide desirably controls the elution speed of the copper glass and 10 the metal pyrithione, and thus the active substances are eluted at a stable speed for a long period. [0014] Here, coating compositions containing the three components of monovalent copper-containing copper glass, a metal pyrithione and titanium oxide, and 15 coating compositions containing the three components of copper oxide (I), a metal pyrithione and titanium oxide were also investigated. However, both compositions were inferior in long-term antifouling effect when compared with the coating composition according to the present invention. Accordingly, it became obvious that the extremely excellent long-term antifou'ling effect 20 exhibited by the coating composition according to the present invention can be achieved only by allowing the antifouling coating composition to contain three components of (A) divalent copper-containing copper glass, (B) a metal pyrithione and (C) titanium oxide at a certain ratio, and thus the present invention has been accomplished. 25 ADVANTAGEOUS EFFECTS OF THE INVENTION [0015) Embodiments of the present invention provide an antifouling coating composition which can exhibit a long-term antifouling effect even in the sea area 5 where animals such as barnacles and serpula, and coelenterates such as hydrozan show high activity. DESCRIPTION OF EMBODIMENTS 5 [0016] The antifouling coating composition according to the present invention contains (A) divalent copper-containing copper glass, (B) a metal pyrithione and (C) titanium oxide, wherein the metal pyrithione contains copper or zinc as the metal, the antifouling coating composition further comprises a spreading resin, 10 the copper glass (A) contains CuO by 25 to 40 % by mol, the content of the copper glass (A) by solid is 1 to 20 % by mass with respect to the solids of the antifouling coating composition, the content of the metal pyrithione (B) by solid is 25 to 150 parts by mass with respect to 100 parts by mass of the copper glass (A), and the content of titanium oxide (C) by solid is 50 to 300 parts by mass with respect to 15 100 parts by mass of the copper glass (A). [00171 <Copper Glass (A)> The copper glass (A) employed in the present invention is a glass containing divalent copper, and the copper glass contains CuO by 25 to 40 % by mol. 20 There is no limitation to the composition of the glass so long as the glass can dissolve and elute copper at a desirable speed, Here, phosphate glass (glass containing P 2 0 5 as major component) is preferable, and P 2 0 5 -Na20-CuO-based glass is further preferable, When phosphate glass is employed, the amount of copper eluted with respect to the amount of glass dissolved can be increased, 25 compared with the case where silica glass is employed. The phosphate glass can also achieve stable elution. Therefore, the effect of the coating composition according to the present invention can be further improved when the composition is prepared with phosphate glass containing divalent copper In addition, since Na2O has a nature to break the bond between the phosphorus 6 atom and the oxygen atom of the phosphoric acid, the solubility of the glass component in water can be enhanced by adding Na2O to the phosphate glass. There is no limitation to the content of P 2 0 5 , Na 2 O and CuO. It is further preferable that the content of CuO is 30 to 40 % by mol, since Cu can be eluted 5 stably and desirably when the content is such. The molar ratio of P 2 0 5 to Na2O can substantially be the same (that is, P 2 03/Na 2 O=0.8 to 1.2) or can be different. Specific composition of the glass (molar ratio) is, for example, P20 3 /Na2O/CuO =35/35/30 or P20/Na20/CuO=30/30/40. [0018] .0 The copper glass (A) can be manufactured by formulating and blending the raw materials for the composition such as sodium phosphate, copper oxide (II) and the like, and then melting them at 1000 to 1200*C for 30 minutes to 2 hours. The molten glass is then poured onto an iron plate, cooled, and pulverized to 1 to 100 pm by a planetary ball mill. 5 [0019] The content of the copper glass (A) by solid is 1 to 20 % by mass with respect to the solids of the composition according to the present invention. For example, the content is 1., 2, 5, 10, 15 or 20 % by mass, or may be in the range between any of the two values referred herein. 20 [0020] <Metal Pyrithione (B)> Examples of the metal pyrithione (B) employed in the present invention include bis(2-sulfidepyridine- 1 -olato)copper (copper pyrithione), bis(2-sulfidepyridine-1-olato)zine (zinc pyrithione) and the like. Among these, 25 metal bis-pyrithiones (pyrithiones of divalent metals such as copper pyrithione and zinc pyrithione) are preferable, and copper pyrithione is particularly preferable. Ones that are commercially available can be employed as metal pyrithiones. Examples of such commercially available metal pyrithiones 7 include Copper Omadine Powder, Zinc Omadine Powder (both available from Arch Chemicals Japan, Inc) and the like. [0021] The content of the metal pyrithione (B) by solid is 25 to 150 parts by mass 5 with respect to 100 parts by mass of the copper glass (A), For example, the content is 25, 50, 100, 150, 200 or 250 parts by mass, or may be in the range between any of the two values referred herein, When the content is in such range, the antifouling effect against animals such as barnacles and serpula, and coelenterates such as hydrozan is particularly excellent. [0 [0022] Titanium Oxide (C)> Examples of the titanium oxide (C) employed in the present invention include titanium oxide of rutile type, anatase type or brookite type. These titanium oxides can be employed alone, or two or more kinds of the titanium 15 oxides can be employed in combination. [0023] Among the titanium oxides, it is particularly preferable to employ titanium oxide of rutile type, since it is unlikely to causes chalking (phenomenon or state in which a pigment of the color component of the coating forms a chalky powder, 20 which occurs when the surface resin of the coating weathers due to exposure to ultraviolet ray, heat, moisture, wind or the like). As the titanium oxide employed in the present invention, titanium oxide having an average particle diameter of 0.001 pm to 10 pm is preferable, and titanium oxide having an average particle diameter of 0, 1 pm to 3 pm is 25 particularly preferable. [0024] Here, the average particle diameter of the afore-mentioned titanium oxide is a value of a median diameter (50% cumulative particle diameter) calculated from volume average diameter measured by laser diffraction/ scattering method 8 Specifically, it is a value obtained when the laser diffraction/ scattering particle size analyzer, optical equipment of MT3300 available from NIKKISO CO., LTD was employed with methanol as the dispersion solvent, and the measurement was conducted at 25 *C. 5 [0025] As the titanium oxide employed in the present invention, titanium oxide having an oil absorption of 1mI/100g to 1000ml/100g is preferable, and titanium oxide having an oil absorption of 3mlO/100g to 50ml/100g is particularly preferable, to [0026] The surface of the titanium oxide employed in the present invention may be treated. For example, the surface of the titanium oxide may be treated with a coating film comprising an oxide of one or more element selected from the group consisting of Al, Si, Zr, Sb, Cr and Ti, and an organosilicon compound. [5 Commercially available titanium oxides can be employed. Examples of such commercially available titanium oxides include "FR-41" (available from FURUKAWA CHEMICALS CO,, LTD), "R-5N" (available from SAKAI CHEMICAL INDUSTRY CO., LTD), "R-820" and "R-830" (available from ISHIHARA SANGYO KAISFIA, LTD.) and the like. 20 [0027] The content of titanium oxide (C) by solid is 50 to 300 parts by mass with respect to 100 parts by mass of the copper glass (A). For example, the content is 50, 100, 150, 200, 250 or 300 parts by mass, or may be in the range between any of the two values referred herein. When the content is in such range, the effect 25 according to the present invention can be further enhanced. 10028] <0ther Additional Component> The antifouling coating composition employed in the present invention contains a spreading resin, and further contains eluting adjuvant, other 9 antifoulant, antisettling agent, anti-sagging agent, plasticizer, surfactant, antifoaming agents, dyes, pigments, organic solvent, water and the like, arbitrarily at an arbitrary ratio, so long as it does not alter the purpose of the present invention. 5 [0029] (Eluting Adjuvant) Examples of the eluting adjuvant include silicone oil, ethylene/ci-olefin copolymer, polybutenes, paraffins, vaselines, dialkylsulfide compound and the like. By allowing the composition to contain the eluting adjuvant, the eluting [0 speed of the coating film can be desirably controlled, and thus long-term antifouling effect can be exhibited. Here, there is no limitation for the content of the eluting adjuvant, and the content of the eluting adjuvant by solid is usually 0.1 to 35 % by mass, preferably 1 to 30 % by mass with respect to the solids of the composition 15 according to the present invention. [0030] Examples of the silicone oil include polydimethylsiloxane, polymethylphenylsiloxane, methylphenylsiloxane-dimethylsiloxane copolymer, polyether modified polydimethylsiloxane, polyether modified 20 polyalkyl(methyl)siloxane, polyester modified polydimethylsiloxane, long-chain alkyl modified polydi methylsiloxane, aralkyl modified polydimethylsiloxane, polyether long-chain alkyl aralkyl modified dimethyl silicone oil, fluorosilicone oil, amino modified silicone oil and other modified silicone oils modified with various kinds of functional group. In particular, polyether modified silicone oil having a 25 hydrophilic-lipophilic balance (HLB value) of 0,5 to 9 is preferable. Specifically, polyether modified polydimethylsiloxane or polyether long-chain alkyl aralkyl modified dimethyl silicone oil having a hydrophilic-lipophilic balance (HLB value) of 0.5 to 9 is preferable. Polyether modified polydimethylsiloxane or polyether long-chain alkyl aralkyl modified dimethyl silicone oil having a 10 hydrophilic-lipophilic balance (HLB value) of 1 to 5 can be mentioned as the silicone oils that are furthermore preferred. In the present invention, these silicone oils may be employed alone, or two or more kinds of them may be employed in combination. 5 From the aspect of coating workability and physical properties, the viscosity of the silicone oil is preferably 1000 poise or lower, and more preferably 100 poise or lower. [0031} Examples of the ethylene/a-olefin copolymer include an ethylene/a-olefin to copolymer represented by the general formula (I): [Chemical formula 1] Ri CH, CH 2 C> (CH (wherein RI is a linear or branched alkyl group with carbon atoms of I to 10; x, 15 y and p, being identical with or different from each other, are each an integer of I or larger). As the linear or branched alkyl group with carbon atoms of I to 10, which is represented by R1, an alkyl group with carbon atoms of 1 to 4 such as methyl group, ethyl group, propyl, isopropyl, butyl group, isobutyl group and the like 20 are preferable, and methyl group is more preferable. [00321 The ethylene/a-olefin copolymer represented by the general formula (I) is a copolymer obtained by copolymerizing ethylene with a-olefin, The ethylene/a-olefin copolymer may be a random copolymer, a block copolymer or a. 25 graft copolymer. 11 A commercially available ethylene/a-olefin copolymer can be employed, Examples of the commercially available ethylene/a-olefin copolymer include LUCANT HC-10, LUCANT HC-20, LUCANT HC-40, LUCANT HC-100, LUCANT HC-150, LUCANT HC-600, LUCANT HC-2000 (each of them being a registered 5 trademark and available from Mitsui Chemicals, Inc) and the like. These ethylene/a-olefin copolymers may be employed alone, or two or more kinds of them may be employed in combination. [0033] From the aspect of coating workability and physical properties of the film, .0 the number average molecular weight (Mn) of the ethylene/a-olefin copolymer is preferably 10,000 or lower, and more preferably 1,000 to 3,000. The viscosity of the ethylene/a-olefin copolymer at 0 *C is preferably 20,000 PaS or lower, and is more preferably 500 PaS or lower. t0034] 15 Examples of the polybutenes include polybutene, polyisobutene and the like. Here, commercially available polybutenes can be employed. Examples of the commercially available polybutenes include polybutene LV-7, polybutene LV- 10, polybutene LV-25, polybutene LV-50, polybutene LV-100, polybutene HV-35, polybutene HV-100, polybutene HV-300 and polybutene HV-1900 (all available :0 from Nisseki Chemical Inc.); polybutene OH, polybutene 5H, polybutene 10H, polybutene 300H, polybutene 2000H, polybutene OR, polybutene 15R, polybutene 35R, polybutene 10CR and polybutene 350R (all available from Idemitsu Petrochemical Co., Ltd.); polybutene ON, polybutene 06N, polybutene 3N, polybutene 10SH and polybutene 200N (all available from NOF 25 CORPORATION) and the like. [0035] Examples of the paraffins include n-paraffin, solid paraffin, liquid. paraffin, chlorinated paraffin and the like, [0036] 12 Examples of the vaselines include white vaseline, yellow vaseline and the like, [0037] Examples of the di-alkyl sulfide compound include di-tertbutyl decasulfide, 5 dipentyl tetrasulfide, dipentyl pentasulfide, dipentyl decasulfide, dioctyl tetrasulfide, dioctyl pentasulfide, dinonyl tetrasulfide, dinonyl pentasulfide, di-tert-nonyl tetrasulfide, di-tert-nonylpentasulfide, didecyl tetrasulfide, didodecyl tetrasulfide, dioctadecyl tetrasufide, dinonadecyl tetrasulfide and the like. Lo [0038] (Spreading Resin) Synthetic resin and natural resin can be employed as the spreading resin, Workability during the formation of the coating film can be improved by adding the spreading resin to the composition. In addition, a coating film having 15 excellent adhering property with an object to be coated can be formed. Examples of the synthetic resin include vinyl resin, alkyd resin, acrylic resin, urethane resin, polyester resin, synthetic rubber, chlorinated polyethylene and the like. Examples of the vinyl resin include vinyl chloride-vinyl acetate copolymer, vinyl chloride-alkyl vinyl ether copolymer, vinyl chloride resin and ?o the like. [0039] Examples of the natural resin include wood rosin, gum rosin, modified rosin and the like. [0040] 25 In particular, it is preferable that the spreading resin contains acrylic resin. The glass-transition temperature (Tg) of the spreading resin is preferably -100 to 100 'C, and. more preferably -50 to 80 *C, The weight-average molecular weight (Mw) of the spreading resin is preferably 5, 000 to 1, 000, 000, and more preferably 10, 000 to 500,000, There is no limitation for the content of the 13 spreading resin according to the present invention, and the content is usually 0,1 to 80 % byr mass, and preferably 1 to 45 % by mass by solid with respect to the solids of the composition [0041] 5 (Other Antifoulant) As an antifoulant other than the divalent copper-containing copper glass (A) and the metal pyrithione (B) employed in the present invention, the following antifoulants can be added to the composition. The coating film thus formed can exhibit a further desirable antifouling effect. 10 [0042] Examples of the other antifoulant include tetraalkylthiuram disulfide compounds such as tetramethylthiuram disulfide, tetraethylthiuram disulfide and the like. Further examples include chloromethyl-n-octyl disulfide, N,N-dimethyldichlorophenyl urea, N-(fluorodichloromethylthio)phthailimide, 15 N,N -dimethyl-N -phenyl-(N-fluorodichloromethylthio) sulfamide, N,N'- dimethyl -N -tolyl-(N-fluorodichlorom ethylthio)suIfamide, 4,5 -dichloro-2- n-octyl-4-isothiazoline-3-one, 2 ,3-dichloro-N-(2,6-diethylphenyl) maleimide, 2,3--dichloro-N-(2'- ethyl, 6 -methylphernyl)maleimide, 3-benzo[bjthiene-2-yl-5,6-dihydro-1,4,2-oxathiazine-4-oxide, 20 2-(p-chlorophenyl)-3-cyano-4-bromo-5-trifluoromethylpyrrole, tetrachloro-isophthalonitrile and the like. [0043] The particularly preferred other antifoulant employed in combination with the copper glass (A) and the metal pyrithione (B) is 4, 5-dichloro-2-n-octyl-4 25 isothiazoline-3-one. [0044] There is no limitation for the content of the other antifoulant, and the content of the other antifoulant is usually 0. 1 to 80 % by mass, preferably 1 to 14 50 % by mass by solid with respect to the solids of the composition according to the present invention. [0045] (Antisettling Agent/Anti-sagging Agent) 5 Examples of the antisettling agent/ anti-sagging agent include polyethylene wax, wax based on hydrogenated castor oil, wax based on polyamide, amide-wax, wax based on oxidized polyethylene and the like. Wax based on hydrogenated castor oil, wax based on polyamide, amide-wax and wax based on oxidized polyethylene are preferable. These antisettling agent/anti-sagging agents may 10 be employed alone, or two or more kinds of them may be employed in combination. [0046] (Plasticizer) Examples of the plasticizer include phthalic acid ester, adipic acid ester, 15 phosphate ester and the like. Examples of the phthalic acid ester include dibutyl phthalate, dioctyl phthalate and di-2-ethylhexyl phthalate; examples of adipic acid ester include dibutyl adipate, dioctyl adipate and 2-ethylhexyl adipate; and examples of phosphate ester include tricresyl phosphate and trioctyl phosphate. These plasticizers may be employed alone, or two or more 20 kinds of them may be employed in combination. [0047] (Organic Solvent) As the organic solvent, aromatic solvents such as xylene, toluene, Solvesso 1.00, Solvesso 150 (each being a registered trademark, and available from Exxon 25 Mobil Corporation) and the like; ketone-based solvents such as isobutyl methyl ketone (MIBK), di-isobutyl ketone (DIBK) and the like; ester-based solvents such as butyl acetate, isobutyl acetate, isoamyl acetate and the like can be employed. Further, an organic solvent which is low in toxicity, low in odor and takes environmental burden into consideration can be employed. Examples of such 15 organic solvents include aromatic/ cycloaliphatic/ aliphatic hydrocarbon solvent mixtures such as Pegasol AN45, Pegasol AS100 (each being a registered trademark, and available from Exxon Mobil Corporation), LAWS, HAWS (each being a available from Shell Chemicals) and the like; glycol ester solvents such as 5 propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate and the like; cycloaliphatic hydrocarbon solvents such as ethylcyclohexane, dimethylcyclohexane, RIKASOLV (registered trademark) 900 (hydrogenated C9 aromatic compound), RIKASOLV (registered trademark) 1000 (hydrogenated C10 aromatic compound) and the like; cycloaliphatic/aliphatic [0 hydrocarbon solvent mixtures such as ShellSol D40 (registered trademark, available from Shell Chemicals, Exol D30, Exol D40 (each of them being a registered trademark, available from Exxon Mobil Corporation); aliphatic hydrocarbon solvent mixtures such as Isopar G, Isopar H (each of them being a registered trademark, available from Exxon Mobil Corporation) and the like. 15 These organic solvents can be employed alone or two or more kinds of them can be employed in combination. [0048] The composition according to the present invention can be employed to form an antifouling coating film for various fishing tools, underwater structures and 20 the like, In particular, the composition according to the present invention can be employed preferably as an antifouling coating composition for fishing nets. [0049] The antifouling coating composition for the fishing nets according to the present invention can be prepared by mixing the afore-mentioned components of 25 [A] to [C]. In addition to the components of [A] to [C], the afore-mentioned components can be employed with the composition as necessary. The amount of each of the components added shall be adjusted so as to meet the afore-mentioned formulation amount and content. The order of the 16 components to be added is not limited. Known method for mixing shall be adopted. For example, mixing may be conducted using a stirring apparatus. [0050] Method of Forming an Antifouling Coating Film onto Fishing Nets. 5 Antifouling Coating Film, and Coated Object The method of forming an antifouling coating film onto the fishing nets in accordance with an embodiment of the present invention is characterized in that the afore-mentioned antifouling coating composition for the fishing nets is employed when the antifouling coating film is formed on the surface of the object 10 to be coated. The antifouling film obtained by the forming method according to the present invention can prevent attachment of the aquatic fouling organism, since the surface of the film gradually dissolves and thus the surface is constantly renewed. In addition, the afore-mentioned composition can be coated on top after the coating film is dissolved, so that the antifouling effect can 15 be exhibited continuously. [00513 Examples of the object to be coated include fishing tools, underwater structures and the like. Examples of the fishing tools include fishing nets for cultivation or for fixed fishery, fishing net accessories used for float, rope and the 20 like. Examples of the underwater structures include power plant aqueduct, bridges, port facilities and the like. [0052] The antifouling coating film coated on the fishing nets according to the present invention can be formed by applying the afore-mentioned antifouling 25 coating composition for fishing nets onto the surface (entirely or partially) of the object to be coated. [00531 Examples of the method of application include brush coating, spray coating, dipping, flow coating, spin coating and the like. These methods may be 17 employed alone, or two or more kinds of the methods may be employed in combination. For example, when the antifouling coating composition for fishing nets according to the present invention is applied onto the fishing nets, dipping method is preferably employed. 5 [0054] The coating film is dried after being applied. The coating film is suitably dried at room temperature. The time required for drying can be selected depending on the amount of the antifouling coating for fishing nets being applied, 0 [0055] The amount of the antifouling coating for fishing nets being coated shall be selected depending on the type of the object to be coated. For example, when the object to be coated is the fishing nets, the amount of the dried coating with respect to 100 parts by mass of the fishing nets is preferably 1 to 35 parts by 15 mass, and more preferably 4 to 20 parts by mass. [0056] The surface of the coated object according to the present invention is provided with the afore-mentioned antifouling coating film. The coated object according to the present invention may have the afore-mentioned antifouling 2o coating film on the entire surface or partially on the surface, EXAMPLES [0057] The following illustrates Examples, etc., and further clarifies characteristics 25 according to the present invention. The present invention, however, is not limited to these Examples. [0058] Comparative Production Example I (Production of Copper Glass Containing Monovalent Copper, H-1) 18 The glass component materials and the copper compound in the composition ratio mentioned below were uniformly mixed, and then the mixture was melted by using a gas furnace at 1100 to 1300 *C for 60 minutes, followed by rapid cooling. The soluble glass containing monovalent copper was thus 5 manufactured, and then the soluble glass was pulverized using a ball mill to obtain monovalent copper-containing copper glass powder, [0059 <Composition> SiO 2 : 7.7 parts by mass o A1 2 0 3 : 0 1 parts by mass Na2O: 5.9 parts by mass B203: 28.8 parts by mass CU20: 53.3 parts by mass ZnO: 4.2 parts by mass 15 [0060} Examples 1 to 6 and Comparative Examoles I to 12 The antifouling coating composition was obtained by mixing the formulating components given in Table 1 by the ratio (% by mass) given in Table 1. [00611 20 Product name "PNU-40": divalent copper-containing copper glass

(P

2 0s/Na2O/CuO = 30/30/40 (% by mol), average particle diameter 3 pm, available from TOYO GLASS CO., LTD.) Product name "PNU-30": divalent copper-containing copper glass

(P,

2 Os/Na20/CuO = 35/35/30 (% by mol), average particle diameter 3 -pm, 25 available from TOYO GLASS CO., LTD.) Product name "NC-301": Copper Oxide (1) (available from NISSIN CHEMCO Co., Ltd.) Product name " Zinc Oxide Type-2": zinc oxide (available from Seido Chemical Industry Co., Ltd.) 19 Product name "NOCCELER PZ": zinc dimethyldithiocarbamate (available from OUCHI SHINKO CHEMICAL INDUSTRIAL) Product name "NOCCELER TET-G"; tetraethylthiuran disulfide (available from OUCHI SHINKO CHEMICAL INDUSTRIAL) Product name "Copper Omadine Powder": bis (2 -sulfidepyridin -I -olato) copper (available from Arch Chemicals Japan, Inc) Product name "Zinc Omadine Powder", bis(2-sulfidepyridin-1-olato)zinc (available from Arch Chemicals Japan, Inc) Product name "FR-4 I": titanium oxide (rutile type titanium oxide, available to from FURUKAWA CHEMICALS CO,, LTD) Product name " Zinc Oxide Type-2": zinc oxide (available from Seido Chemical Industry Co., Ltd.) Product name "TINUVIN P": 2- (5-methyl-2-hydroxyphenyl)benzotriazole (available from Nagase & Co., Ltd.) 15 Product name "NITTOL HN": xylene solution of acrylic resin (solid content 40%, Tg= ca. 20 'C, Mw= ca, 230000, available from NITTO KASEI CO., LTD.) Product name "KF-6020": polyether modified dimethyl silicone oil (available from Shin-Etsu Chemical Co, Ltd) Product name "X-22-2516": polyether long-chain alkyl-aralkyl modified 20 dimethyl silicone oil (available from Shin-Etsu Chemical Co, Ltd) Product name "LUCANT H C-40": ethylene/ a-olefin copolymer (available from Mitsui Chemicals, Ine) Product name "Polybutene ON": polybutene (available from NOF CORPORATION) 25 Product name "Disparlon 4200-20": oxidized polyethylene-based wax (solid content 20%, available from Kusumoto Chemicals, Ltd.) Product name "Disparlon A630-20X": polyamide -based wax (solid content 20%, available from Kusumoto Chemicals, Ltd.) Xylene: available from Kishida Chemical Co., Ltd., extra pure reagent 20 [0062] [Table 1] CCI N N N CO N I N nI N ( r NN N C C - -- L L-- N i CC I2n N jU J - - -- -- - C ~ - S izin 1sJ2N [00631 Test Example 1 (Test for Confirming Antifouling Effect) Polyethylene fishing nets (400 denier, 40 strings, 8 knots per foot) were each immersed in each of the antifouling coating composition obtained in Examples 1 5 to 6 and Comparative Examples respectively, and then the fishing nets were dried. Preparation was conducted so that 100 parts by mass of the fishing nets would be applied with 15 parts by mass of the antifouling coating composition. Here, the mass was based on dry coating, The fishing nets thus obtained were fixed onto an SUS frame with the size of 40x60 cm, and were immersed in the sea to of Owase-shi, Mie-prefecture, where the activity of aquatic fouling organisms is high, with the depth at the draft level using a raft. The antifouling properties were evaluated over 12 months by periodic observation. [0064] The evaluation was conducted by the following method. The area with the 1,5 aquatic organism attached (%) was evaluated by taking a picture of the fishing nets from above, after the predetermined time of the test (2, 4, 6, 8, 10 or 12 months) have passed, and then evaluating the area of the fishing nets occupied with the aqueous organism by visual observation, A: Area with the aquatic organism attached is 0% 20 B: Area with the aquatic organism attached is above 0% and less than 10% C: Area with the aquatic organism attached is 10% or more and less than 50% D: Area with the aquatic organism attached is 50% or more Results are shown in Table 2. 25 [00651 [Table 2] 22 Table 2 Antifouling Exampie Comparative Example Effect 2 3 4 5 6 12 3 4 5 6 7 8 | 9 1011 12 2nd month A A A A A A A A A A A A A - A |A- AI A 4th month A A A A A A C A A B A A A A 1 C B 6th month A A A A A A D B B C A A B 6 D D C C 8th month A A A A A A D C C D B B B C D D D D 1Oth month A A A A A A DDDD D D D D 12th month A A B B A B D D D D ID D D D [0066] It can be seen from Table 2 that the antifouling coating compositions of Examples I to 6 are excellent in long-term antifouling effect when compared with 5 any of the antifouling coating compositions of the Comparative Examples of 1 to 12. Examples 1 to 6 contain three components of divalent copper-containing copper glass, a metal pyrithione and titanium oxide. On the other hand, Comparative Example I contains only the divalent copper-containing copper 10 glass, and Comparative Examples 2 and 3 contain on ly the divalent copper-containing copper glass and a metal pyrithione, and Comparative Example 4 contains the divalent copper-containing copper glass and titanium oxide. The long-term antifouling effects of Comparative Examples 1 to 4 were far lower than those of Examples 1 to 6. These results revealed that it is 15 essential for the antifouling coating composition to include all of the three components mentioned above, in order to exhibit an excellent long-term antifouling effect. When the antifouling coating composition lacks any one of the three components, the long-term antifouling effect lowers drastically. In addition, in Comparative Examples 5 to 8, long-term antifouling effect was 20 studied for the antifouling coating composition containing the three components of monovalent copper-containing copper glass, a metal pyrithione and titanium oxide, or the antifouling coating composition containing the three components of copper oxide (1), a metal pyrithione and titanium oxide. Here, the long-term antifouling effect observed for all of the Comparative Examples 5 to 8 were far 23 lower than those of Examples I to 6. Accordingly, it became apparent that the long-term antifouling effect is highly improved only when divalent copper-containing copper glass was used with a metal pyrithione and titanium oxide. Therefore, similar result cannot be obtained when the monovalent t5 copper-containing copper glass or copper oxide (1) was employed. Comparative Example 9 is directed to an antifouling coating composition containing pyrithione and titanium oxide, but not the monovalent copper-containing copper glass. According to the results of the evaluation of antifouling effect for Comparative Example 9, attachment of aquatic organism to was observed when observation was conducted in the fourth month. The long-term antifouling effect was far lower than those of the Examples. The antifouling coating composition of Comparative Example 10 is obtained by adding zinc oxide to the antifouling coating composition of Comparative Example 9. According to the results of the evaluation of antifouling effect for 15 Comparative Example 10, attachment of aquatic organism was observed when observation was conducted in the fourth month. Therefore, it became apparent that the long-term antifouling effect cannot be improved by the addition of zinc oxide. The antifouling coating composition of Comparative Example 11 is obtained 2O by adding zinc dimethyldithiocarbamate to the antifouling coating composition of Comparative Example 9. According to the results of the evaluation of antifouling effect for Comparative Example 11, the long-term antifouling effect was improved by some extent, however, attachment of aquatic organism was observed when observation was conducted in the fourth month, Therefore, it 25 became apparent that the long-term antifouling effect cannot be improved considerably by the addition of zinc dimethyldithiocarbamate. The antifouling coating composition of Comparative Example 12 is obtained by adding tetraethylthiuram disulfide to the antifouling coating composition of Comparative Example 9. According to the results of the evaluation of 24 antifouling effect for Comparative Example 12, attachment of aquatic organism was observed when observation was conducted in the fourth month. Therefore, it became apparent that the long-term antifouling effect was hardly improved by the addition of tetraethylthiuram disufide. 5 Furthermore, it became apparent that Examples 1, 2 and 5 which contain copper pyrithione were high in long-term antifouling effect when compared with Examples 3, 4 and 6 which contain zinc pyrithione, 25

Claims (3)

1. 3. The antifouling coating composition according to Claim 1 or Claim 2, wherein the titanium oxide is a futile type. 20
2. 4. The antifouling coating composition according to any one of Claims I to 3, further comprising an eluting adjuvant.
3. 5. Fishing nets, fishing net equipments and underwater structures, having an 25 antifouling coating film on the surface thereof, wherein the antifouling coating film is formed with the antifouling coating composition according to any one of Claims I to 4. 26