JP6621121B2 - Copolymer for antifouling paint composition, antifouling paint composition, antifouling coating film formed using the composition, coated product having the coating film on the surface, and antifouling treatment for forming the coating film Method - Google Patents

Description

The present invention relates to a copolymer for an antifouling coating composition, an antifouling coating composition, an antifouling coating film formed using the composition, a coated product having the coating film on the surface, and the coating film The present invention relates to an antifouling treatment method.

Aquatic fouling organisms such as barnacles, cell plastics, blue mussels, scallops, sea squirts, blue sea breams, blue sea breams, slime, etc. By adhering to the surface, there are problems such as damage to the functions of the ship, underwater structure, etc., and loss of appearance. Particularly in the case of a ship, the resistance increases, causing a decrease in speed and an increase in fuel consumption, resulting in a large damage.

Therefore, antifouling paint is applied to the surface of underwater structures such as fishing equipment such as ships (especially the bottom of the ship), fishing nets, fishing net accessories, and power plant conduits. There are ways to prevent serious damage. The use of organotin-containing copolymers conventionally used in this antifouling paint was prohibited, and instead, triorganosilyl group-containing copolymers were developed that have low toxicity and low environmental impact.

In this triorganosilyl group-containing copolymer, the triorganosilyl ester portion is hydrolyzed in seawater, and the copolymer is gradually dissolved in seawater to renew the surface of the coating film. , Tri-n-butylsilyl ester, tri-n-hexylsilyl ester (Patent Document 1), dimethyl n-octylsilyl ester (Patent Documents 2 and 3), dimethyl n-decylsilyl ester (Patent Document 4), dimethyl (n- A co-polymer comprising a triorganosilyl ester having at least one linear alkyl group in the molecule, such as octadecyl) silyl ester (Patent Document 5) and diisopropyl (n-dodecyl) silyl ester (Patent Document 6). When a polymer is used, the storage stability of the paint is poor, the rate of hydrolysis of the paint film is very fast, and the water resistance is poor. The dissolution rate of the control of it was difficult. Therefore, practical application as a ship bottom coating composition has been difficult.

Also, in the case of triorganosilyl ester-containing copolymers consisting of branched alkyl groups or aryl groups such as triisopropylsilyl ester and t-butyldiphenylsilyl ester, the hydrolysis rate is slow and it takes time to start dissolution of the coating film. Therefore, the antifouling effect could not be sufficiently exhibited as it was, and it was difficult to put it to practical use.

Therefore, a copolymer obtained by copolymerizing a triorganosilyl group-containing monomer and (meth) acrylic acid alkoxyalkyl ester such as (meth) acrylic acid 2-methoxyethyl ester (Patent Documents 8, 9, 10), A copolymer obtained by copolymerizing a triorganosilyl group-containing monomer and a (meth) acrylic acid hydroxyalkyl ester such as (meth) acrylic acid 2-hydroxyethyl ester, and a triorganosilyl group-containing material A copolymer (Patent Document 12) obtained by copolymerizing a monomer and a (meth) acrylic acid ester having various functional groups such as (meth) acrylic acid dimethylaminoethyl ester has been proposed.

However, these triorganosilyl group-containing copolymers were able to dissolve to a certain degree of speed and became practical.However, the initial dissolution of the coating film was still small. If the mixing ratio of the monomer is changed to increase the initial coating dissolution, the dissolution of the coating becomes very large over time, and cracks, blisters, etc. ) And the coating film dissolves and disappears in a short period of time.

U.S. Pat. No. 4,593,055 Japanese Patent Laid-Open No. 11-43642 JP 63-118381 A JP-A-9-286933 JP-A-3-31372 Japanese Patent Laid-Open No. 7-18216 JP 2005-82725 A JP-A-7-102193 JP-A-8-199095 JP 2001-226440 A JP 2000-17203 A JP-A-8-269389

The present invention maintains coating film solubility and antifouling effect in seawater from the beginning and maintains stable film solubility and antifouling effect for a long period of time in the seawater. It is another object of the present invention to provide an antifouling paint composition that is also excellent.

According to the invention, the general formula (1):
Wherein R ¹ is a methyl group, R ² , R ³ and R ⁴ are selected from a branched alkyl group having 3 to 8 carbon atoms and a phenyl group, and may be the same or different. It is obtained by copolymerizing a mixture of a methacrylic acid triorganosilyl ester monomer (a) and a polymerizable unsaturated monomer (b) other than the monomer (a),
The monomer (b) contains methyl acrylate;
The content of the monomer (a) accounts for 25 to 65% by mass of the total mass of the monomer (a) and the monomer (b),
There is provided a copolymer for an antifouling coating composition, wherein the content of the methyl acrylate accounts for 25 to 75% by mass of the total mass of the monomer (a) and the monomer (b).

As a result of earnest research, the inventor has obtained a copolymer obtained by adding a specific amount of methyl acrylate to the monomer (b) to be copolymerized with the triorganosilyl ester monomer (a) having a specific structure. When combined (A) is used as a vehicle, the coating film solubility and antifouling effect are good from the beginning in seawater, and even in seawater for a long time, there is no peeling or cracking of the coating film, and the physical properties are good, and it is stable for a long time. The present inventors have found that an antifouling coating composition that maintains the coating film solubility and antifouling effect obtained can be obtained.

Hereinafter, the present invention will be described in detail.
The antifouling coating composition of the present invention contains a triorganosilyl group-containing copolymer (A) and an antifouling agent (B).

<Triorganosilyl group-containing copolymer (A)>
The triorganosilyl group-containing copolymer (A) is:
(A) General formula (1)
Wherein R ¹ is a methyl group, R ² , R ³ and R ⁴ are selected from a branched alkyl group having 3 to 8 carbon atoms and a phenyl group, and may be the same or different. Triorganosilyl group-containing copolymer obtained by copolymerizing a mixture of a methacrylic acid triorganosilyl ester monomer (a) and a polymerizable unsaturated monomer (b) other than the monomer (a). It is.

<Monomer (a)>
In the present invention, examples of the monomer (a) represented by the general formula (1) include triisopropylsilyl methacrylate, triisobutylsilyl methacrylate, tris-butylsilyl methacrylate, triisoamylsilyl methacrylate, methacryl Tris (2-ethylhexyl) silyl acid, triphenylsilyl methacrylate, diisopropylisobutylsilyl methacrylate, diisopropylisoamylsilyl methacrylate, diisopropyl (2-ethylhexyl) silyl methacrylate, diisopropylphenylsilyl methacrylate, diisopropylcyclohexylsilyl methacrylate, methacrylic acid T-Butyldiisopropylsilyl acid, t-butyldiisobutylsilyl methacrylate, t-butyldiisoamylsilyl methacrylate, t-butyl methacrylate Le butyldiphenylsilyl, and the like, preferably, methacrylic acid triisopropylsilyl, particularly preferably methacrylic acid triisopropylsilyl. These monomers are used individually or in combination of two or more.

<Monomer (b)>
The monomer (b) is a monomer copolymerizable with the monomer (a). In the present invention, it is an essential requirement that the monomer (b) contains methyl acrylate, and the monomer (b) contains methyl acrylate. The technical effect is that the soiling effect is sustained.

The monomer (b) may contain only methyl acrylate or may contain monomers other than methyl acrylate. Examples of monomers other than methyl acrylate include the following.
・ Triisopropylsilyl acrylate, triisobutylsilyl acrylate, tris-butylsilyl acrylate, triisoamylsilyl acrylate, tris (2-ethylhexyl) silyl acrylate, triphenylsilyl acrylate, diisopropylisobutylsilyl acrylate, acrylic acid Diisopropylisoamylsilyl, diisopropyl (2-ethylhexyl) silyl acrylate, diisopropylphenylsilyl acrylate, diisopropylcyclohexylsilyl acrylate, t-butyldiisopropylsilyl acrylate, t-butyldiisobutylsilyl acrylate, t-butyldiisoamylsilyl acrylate And acrylic acid triorganosilyl esters such as t-butyldiphenylsilyl acrylate.
・ Methyl methacrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meta ) Phenyl acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, ( (Meth) acrylic acid 2-methoxypropyl, (meth) acrylic acid 4-methoxybutyl, (meth) acrylic acid 2-ethoxyethyl, (meth) acrylic acid polyethylene glycol methyl ether, (meth) acrylic acid dimethylaminoethyl, (meta) ) (Meth) acrylic acid esters such as diethylaminoethyl acrylate
・ Zinc versatic acid (meth) acrylate, magnesium versatate (meth) acrylate, copper versatate (meth) acrylate, zinc octylate (meth) acrylate, magnesium octylate (meth) acrylate, copper octylate (meth) acrylate, laurin Zinc (meth) acrylate, magnesium laurate (meth) acrylate, copper laurate (meth) acrylate, zinc stearate (meth) acrylate, magnesium stearate (meth) acrylate, copper stearate (meth) acrylate (meta ) Metal (meth) acrylates such as metal acrylate pendants, zinc (meth) acrylate and copper (meth) acrylate.
-Vinyl compounds having functional groups such as vinyl chloride, vinylidene chloride, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl benzoate, vinyl butyrate, butyl vinyl ether, lauryl vinyl ether, N-vinyl pyrrolidone.
-Aromatic compounds such as styrene, vinyltoluene, α-methyl styrene.
-Dialkyl ester compounds of unsaturated dibasic acids such as dimethyl malate, dibutyl malate, dimethyl fumarate.

Other copolymerizable monomers other than methyl acrylate are used singly or in combination of two or more, preferably (meth) acrylic acid esters, particularly preferably methyl methacrylate, 2-methoxy methacrylate. Ethyl and 2-methoxyethyl acrylate.

The mass ratio of methyl acrylate in the monomer (b) is, for example, 0.33 to 1, preferably 0.5 to 1, specifically, for example, 0.33, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1 and may be within a range between any two of the numerical values exemplified here. The mass ratio of triorganosilyl esters other than methyl acrylate in monomer (b), (meth) acrylic esters, metal (meth) acrylates, vinyl compounds, aromatic compounds, dialkyl ester compounds is , For example, 0 to 0.5, specifically, for example, 0, 0.1, 0.2, 0.3, 0.4, 0.5, and any of the numerical values exemplified here It may be within a range between the two. Moreover, the mass ratio of the monomer having a hydroxy group or an alkoxy group in the monomer (b) is, for example, 0 to 0.5, specifically, for example, 0, 0.1, 0.2, 0.3, 0.4, and 0.5, and may be within a range between any two of the numerical values exemplified here.

<Synthesis of copolymer (A)>
The copolymer (A) used in the antifouling paint of the present invention can be obtained by copolymerizing a mixture of the monomer (a) and the monomer (b). The copolymerization is performed, for example, in the presence of a polymerization initiator.

Content of the monomer (a) in a mixture is 25-65 mass%, 25-60 mass% is preferable and 25-50 mass% is more preferable. When the content of the monomer (a) is 25 to 65% by mass, the coating film formed using the resulting antifouling coating composition has a coating film abnormality such as cracks in seawater for a long period from the beginning. It does not occur and stable coating film solubility and antifouling performance can be maintained.

The content of methyl acrylate in the mixture is 25 to 75% by mass, preferably 30 to 75% by mass, and more preferably 35 to 75% by mass. When the content of methyl acrylate is 25 to 75% by mass, the coating film formed using the resulting antifouling coating composition has good coating solubility and antifouling effect from the beginning in seawater, and is long. The coating film abnormality such as period peeling and cracking does not occur, and stable coating film solubility and antifouling effect can be maintained for a long time.

The total content of the monomer (a) and methyl acrylate is 70% by mass or more, preferably 80% by mass or more, of the total mass of the monomer (a) and the monomer (b). Preferably it is 90 mass% or more. When it exists in the said range, the coating-film solubility stable for a long period of time is maintained and the especially outstanding antifouling effect is exhibited.

As for the weight average molecular weight of the copolymer of this invention, it is desirable that it is 5000-300000. If the molecular weight is less than 5,000, the antifouling paint film becomes brittle and easily peels and cracks. If it exceeds 300,000, the viscosity of the copolymer solution increases and handling becomes difficult. .

Examples of the polymerization initiator include 2,2′-azobisisobutyronitrile (AIBN), 2,2′-azobis-2-methylbutyronitrile, dimethyl-2,2′-azobisisobutyrate. Azo compounds such as benzoyl peroxide, di-tert-butyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxyisopropyl carbonate, t-butyl peroxy-2-ethylhexanoate, 1,1,3 , Peroxides such as 3-tetramethylbutylperoxy-2-ethylhexanoate, and the like. These polymerization initiators can be used alone or in combination of two or more. As the polymerization initiator, 2,2′-azobisisobutyronitrile and 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate are particularly preferable.

The molecular weight of the triorganosilyl ester-containing copolymer can be adjusted by appropriately setting the amount of the polymerization initiator used.

Examples of the polymerization method include solution polymerization, bulk polymerization, emulsion polymerization, suspension polymerization and the like. Among these, solution polymerization is particularly preferable in that the copolymer (A) can be synthesized easily and accurately.

In the polymerization reaction, an organic solvent may be used as necessary. Examples of the organic solvent include aromatic hydrocarbon solvents such as xylene, ethylbenzene, and toluene. Aliphatic hydrocarbon solvents such as hexane and heptane. Ester solvents such as ethyl acetate, butyl acetate, isobutyl acetate and methoxypropyl acetate. Alcohol solvents such as isopropyl alcohol and butyl alcohol. Ether solvents such as dioxane, diethyl ether and dibutyl ether. Examples thereof include ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone. Among these, an aromatic hydrocarbon solvent is particularly preferable, and xylene is more preferable. These solvents can be used alone or in combination of two or more.

What is necessary is just to set the reaction temperature in a polymerization reaction suitably according to the kind etc. of polymerization initiator, and it is about 70-120 degreeC normally, Preferably it is about 70-100 degreeC. What is necessary is just to set the reaction time in a polymerization reaction suitably according to reaction temperature etc., and is about 4 to 8 hours normally.

The polymerization reaction is preferably performed in an inert gas atmosphere such as nitrogen gas or argon gas.

<Anti-fouling agent (B)>
If the antifouling agent (B) is added to the copolymer (A) of the present invention, an antifouling paint that maintains the antifouling effect for a long period of time can be obtained.

The antifouling agent is not particularly limited as long as it is a substance that has a killing or repelling action against marine fouling organisms. For example, an inorganic chemical | medical agent and an organic chemical | medical agent are mentioned.

Examples of inorganic agents include cuprous oxide, copper thiocyanate (generic name: rhodan copper), cupronickel, copper powder, and the like. Of these, cuprous oxide and rhodan copper are particularly preferred.

Examples of organic agents include organic copper compounds such as 2-mercaptopyridine-N-oxide copper (generic name: copper pyrithione), 2-mercaptopyridine-N-oxide zinc (generic name: zinc pyrithione), zinc ethylenebisdithiocarbamate. (Generic name: dinebu), bis (dimethyldithiocarbamate) zinc (generic name: diram), bis (dimethyldithiocarbamate) ethylenebis (dithiocarbamate) dizinc (generic name: polycarbamate) and other organic zinc compounds; Organic boronation such as triphenylborane, 4-isopropylpyridyl-diphenylmethylborane, 4-phenylpyridyl-diphenylborane, triphenylboron-n-octadecylamine, triphenyl [3- (2-ethylhexyloxy) propylamine] boron Products; maleimide compounds such as 2,4,6-trichloromaleimide, N- (2,6diethylphenyl) 2,3-dichloromaleimide; and others, 4,5-dichloro-2-n-octyl-3-isothiazolone ( General name: Cineine 211), 3,4-dichlorophenyl-N-N-dimethylurea (generic name: diuron), 2-methylthio-4-tert-butylamino-6-cyclopropylamino-s-triazine (generic name: Irgarol 1051), 2,4,5,6-tetrachloroisophthalonitrile (generic name: chlorothalonil), N-dichlorofluoromethylthio-N ′, N′-dimethyl-Np-tolylsulfamide (generic name: Trifluanide), N-dichloromethylthio-N ′, N′-dimethyl-N-phenylsulfamide (generic name: dichlorofluanide) 2- (4-thiazolyl) benzimidazole (generic name: thiabendazole), 3- (benzo [b] thien-2-yl) -5,6-dihydro-1,4,2-oxathiazine-4-oxide (Generic name: betoxazine), 2- (p-chlorophenyl) -3-cyano-4-bromo-5-trifluoromethylpyrrole (generic name: ECONEA 028), and the like. Among these, zinc pyrithione, copper pyrithione, dinebu, diuron, sea nine 211, irgarol 1051, trifluanid, diclofluuride, and ECONEA 028 are preferable, and copper pyrithione, zinc pyrithione, sea nine 211, and ECONEA 028 are more preferable.

These antifouling agents (B) can be used alone or in combination of two or more. The content of the antifouling agent in the composition of the present invention is not particularly limited, but is usually 0.1 to 75% by mass, preferably 1 to 60% by mass in the solid content of the composition of the present invention. When the content of the antifouling agent (B) is less than 0.1% by mass, a sufficient antifouling effect may not be obtained. When the content of the antifouling agent (C) exceeds 75% by mass, the formed coating film is fragile, and further, the adhesion to the coating film formation is weak, and the function as an antifouling coating film is sufficient. I can't do it.

<Other additives>
Furthermore, the antifouling paint resin of the present invention is added with an elution regulator, a plasticizer, a pigment, a dye, an antifoaming agent, a dehydrating agent, a thixotropic agent, an organic solvent, etc. as necessary to obtain an antifouling paint. be able to

Examples of the elution regulator include rosin, rosin derivatives and their metal salts, monocarboxylic acids and salts thereof, or alicyclic hydrocarbon resins. These can be used alone or in combination of two or more.

Examples of the rosin include tall oil rosin, gum rosin, and wood rosin. Examples of the rosin derivative include hydrogenated rosin, disproportionated rosin, maleated rosin, formylated rosin, and polymerized rosin. As the metal salt of rosin and the metal salt of rosin derivative, a reaction product of a metal compound and rosin can be used. Examples of the metal salt of rosin include gum rosin zinc (or copper) salt, wood rosin zinc (or copper) salt, Examples include tall oil rosin zinc (or copper) salt. As metal salts of rosin derivatives, hydrogenated rosin zinc (or copper) salt, disproportionated rosin zinc (or copper) salt, maleated rosin zinc (or copper) salt, formylated rosin zinc (or copper) salt, polymerization Examples include rosin zinc (or copper) salt.

Examples of the monocarboxylic acid include fatty acids having about 5 to 30 carbon atoms, synthetic fatty acids, and naphthenic acids. Examples of the monocarboxylic acid salt include a copper salt, a zinc salt, a magnesium salt, and a calcium salt.

Examples of the alicyclic hydrocarbon resin include Quinton 1500, 1525L, 1700 (trade name, manufactured by Nippon Zeon Co., Ltd.) and the like as commercially available products.

Examples of the plasticizer include phosphate esters such as tricresyl phosphate, trioctyl phosphate and triphenyl phosphate, phthalates such as dibutyl phthalate and dioctyl phthalate, and adipic acid such as dibutyl adipate and dioctyl adipate. Esters, sebacic acid 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, polyethylene Polyalkylene glycols such as glycol and polypropylene glycol, t-nonyl pentasulfide, petrolatum, polybutene, trimellitic acid tris (2-ethylhexyl), silicone oil, Dynamic paraffins, and chlorinated paraffins. These can be used alone or in combination of two or more.

Examples of the pigment include bengara, talc, titanium oxide, silica, calcium carbonate, barium sulfate, calcium oxide, and the like, and can be used alone or in combination of two or more.

Examples of the dye include various organic dyes soluble in organic solvents.

Examples of the antifoaming agent include a silicone resin antifoaming agent and an acrylic resin antifoaming agent.

Examples of the dehydrating agent include synthetic zeolite-based adsorbents, orthoesters, silicates such as tetraethoxysilane, isocyanates, and the like. These can be used alone or in combination of two or more.

Examples of the thixotropic agent include bentonite, fatty acid amide wax, polyethylene oxide, and various amide compounds. These can be used alone or in combination of two or more.

As said organic solvent, what is normally mix | blended with antifouling paints, such as an aliphatic solvent, an aromatic solvent, a ketone solvent, an ester solvent, an ether solvent, is mentioned, for example. These can be used alone or in combination of two or more.

<Method for producing antifouling paint composition>
The antifouling coating composition of the present invention is produced, for example, by mixing and dispersing a mixed solution containing the copolymer (A), the antifouling agent (B), and other additives using a disperser. it can.

What is necessary is just to adjust suitably content of the said copolymer, antifouling agent, etc. in the said liquid mixture so that it may become content of the copolymer, antifouling agent, etc. in an antifouling coating composition, respectively.

The mixed solution is preferably prepared by dissolving or dispersing various materials such as a copolymer and an antifouling agent in a solvent. As said solvent, the thing similar to the said organic solvent can be used.

As the disperser, for example, one that can be used as a fine pulverizer can be suitably used. For example, a commercially available homomixer, sand mill, bead mill or the like can be used. Alternatively, the mixed solution may be mixed and dispersed using a container provided with a stirrer to which glass beads for mixing and dispersing are added.

<Anti-fouling treatment method, anti-fouling coating film, and painted product>
In the antifouling treatment method of the present invention, the antifouling coating film is formed on the surface of the coating film forming article using the 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 constantly renewed, thereby preventing the adhesion of chickenpox fouling organisms. Moreover, after dissolving a coating film, the antifouling effect can be exhibited continuously by overcoating the said composition.

Examples of the coating film formation include ships (particularly ship bottoms), fishing equipment, underwater structures, and the like. Examples of the fishery tools include aquaculture or stationary fishing nets, fishing net accessories such as floats and ropes used in the fishing nets, and the like. Examples of the underwater structure include a power plant conduit, a bridge, a port facility, and the like.

The antifouling coating film can be formed by applying the antifouling coating composition to the surface (entirely or partly) of the coating film forming article. Examples of the application method include brush coating, spraying, dipping, flow coating, and spin coating. These may be used alone or in combination of two or more. After application, dry. The drying temperature may be room temperature. What is necessary is just to set drying time suitably according to the thickness etc. of a coating film.

The antifouling coating film of the present invention formed using the antifouling coating composition exhibits an appropriate coating film dissolution rate and coating film properties in seawater, and can maintain a stable surface renewability over a long period of time. The desired antifouling effect can be effectively exhibited. Moreover, it has the advantage that the outstanding recoat performance of a coating film can be exhibited.

What is necessary is just to set the thickness of an antifouling coating film suitably according to the kind of coating-film formation thing, the navigation speed of a ship, seawater temperature, etc. For example, when the coating film formation is the bottom of a ship, the thickness of the antifouling coating is usually 50 to 500 μm, preferably 100 to 400 μm. The antifouling coating film of the present invention has an appropriate hardness. That is, the antifouling coating film of the present invention has a hardness that does not cause coating film abnormality such as cold flow.

The coated article of the present invention has the antifouling coating film on the surface. The coated product of the present invention may have the antifouling coating film on the entire surface or a part thereof. Since the coated product of the present invention has a coating film excellent in long-term stable surface renewability and recoatability by improving an appropriate coating film dissolution rate and coating film properties in seawater, In particular, it can be suitably used as ship bottoms), fishing equipment, underwater structures and the like. For example, when the antifouling coating film is formed on the ship bottom surface of the ship, the antifouling coating film gradually dissolves from the surface, and the coating film surface is constantly renewed, thereby preventing adhesion of waterpox fouling organisms. it can.

Moreover, the antifouling coating film has a high coating film solubility from the beginning of immersion in seawater and can be stably maintained for a long period of time. Therefore, the ship can maintain antifouling performance for a long period of time. For example, even in a stationary state such as during berthing or during outfitting, there is little adhesion and accumulation of Minamata fouling organisms, and the antifouling effect can be exhibited for a long period of time. In addition, even after a long period of time, the antifouling coating on the surface is basically free from cracks or peeling. Therefore, it is not necessary to perform another operation such as forming a coating film after the coating film is completely removed. Therefore, an antifouling coating film can be suitably formed by directly overcoating the antifouling coating film composition. Thereby, it is possible to easily and continuously maintain the antifouling performance at a low cost.

Examples and the like are shown below to further clarify the features of the present invention. However, the present invention is not limited to these examples.
% In each production example, reference example, example and comparative example represents mass%.

The heating residue is a value obtained by heating at 125 ° C. for 1 hour based on JIS K 5601-1-2 (ISO 3251).

The weight average molecular weight (Mw) is a value (polystyrene conversion value) determined by GPC.
The conditions of GPC are as follows.
Equipment: HLC-8220GPC manufactured by Tosoh Corporation
Column: TSKgel SuperHZM-M (manufactured by Tosoh Corporation) 2 flow rate: 0.35 mL / min
Detector ... RI
Column bath temperature ... 40 ° C
Eluent: THF

Moreover, the unit of the compounding quantity of each component in a table | surface is g.

<Production Example 1 (Production of Copolymer P-1)>
After charging 400 g of xylene into a 2000 ml flask equipped with a thermometer, reflux condenser, stirrer and dropping funnel, the temperature was raised to 83-87 ° C. under a nitrogen atmosphere, and 150 g of triisopropylsilyl methacrylate was stirred, While keeping a mixed liquid of 350 g of methyl acrylate and 5 g of 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (Nippon Yushi Co., Ltd. Perocta O) at 83 to 87 ° C., it was added dropwise over 1 hour. After dropping, 0.5 g of 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate was added three times every hour while maintaining the temperature at 83 to 87 ° C. to complete the polymerization reaction. By adding 100 g and dissolving, copolymer solution P-1 was obtained. The heating residue of P-1 was 49.8%, and the weight average molecular weight was 55000.

<Production Examples 2-8, Reference Examples 1-18>
Using the organic solvents, monomers, and polymerization initiators shown in Tables 1 and 2, polymerization is performed in the same manner as in Production Example 1, and copolymer solutions P-2 to P-8 and comparative copolymer solution H are used. -1 to H-18 were obtained. The heating residue and weight average molecular weight of each copolymer solution obtained were measured.
The results are shown in Tables 1 and 2.

<Examples 1-11, Comparative Examples 1-18>
Using the copolymer solutions P-1 to P-8 obtained in Production Examples 1 to 8 and Reference Examples 1 to 18, and comparative copolymer solutions H-1 to H-18, the antifouling paint compositions are shown in Table 3. -Prepared according to the formulation shown in Table 4.

(Measurement of coating hardness)
The coating film hardness in the paint was measured with a pendulum hardness meter.
The coating film hardness is measured with a pendulum hardness meter by applying each paint sample to a glass plate (100 × 200 × 2 mm) so that the thickness after drying is about 100 μm, drying at 40 ° C. for one day, and then at a room temperature of 25 ° C. I went there. The value is a count number.
The results are shown in Tables 3-4.

(Solubility test of coating film (rotary test))
A rotating drum having a diameter of 515 mm and a height of 440 mm was attached to the center of the water tank so that it could be rotated by a motor. In addition, a cooling device for keeping the temperature of the seawater constant and an automatic pH controller for keeping the pH of the seawater constant were attached.
The test plate for the rotary test was produced according to the following method.
First, on a titanium plate (71 x 100 x 0.5 mm), a rust preventive paint (epoxy vinyl A / C) is applied so that the thickness after drying is about 100 μm and dried to form a rust preventive coating. did. Thereafter, the coating compositions obtained in Examples 1 to 11 and Comparative Examples 1 to 18 were applied on the rust preventive coating so that the thickness after drying was about 300 μm. The obtained coated material was dried at 40 ° C. for 3 days to prepare a test plate having a dry coating film having a thickness of about 300 μm.
The produced test plate was 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. Meanwhile, the temperature of the seawater was maintained at 25 ° C. and the pH at 8.0 to 8.2, and the seawater was replaced every week.
One month by measuring the initial thickness of each test plate and the remaining film thickness every month after the start of the test with a shape measuring laser microscope VK-X100 manufactured by Keyence Corporation, and calculating the dissolved coating thickness from the difference The coating film dissolution amount (μm / month) was obtained.
Moreover, at the time of the measurement of the residual film thickness after six months of a rotary test, each coating-film surface was observed with the naked eye and the microscope, and the surface state of the coating film was evaluated.

Evaluation was performed according to the following criteria.
◎: When there is no abnormality ○: Some hair cracks are seen Δ: Hair cracks are seen over the entire surface of the coating film ×: Some abnormalities are seen in the coating film such as cracks, blisters or peelings Table 3 To Table 4.

(Anti-fouling test (stationary immersion test))
Each of the antifouling paints obtained in Examples 1 to 11 and Comparative Examples 1 to 18 was applied to both surfaces of a hard PVC plate (100 × 200 × 2 mm) so as to have a dry coating thickness of about 200 microns. This test plate was submerged 1.5 m below the sea level in Owase City, Mie Prefecture, and the test plate was observed for 6 months for contamination by attached organisms and evaluated. The results are shown in Tables 3-4.

Evaluation was performed by visually observing the state of the coating film surface, and was judged according to the following criteria.
A: There is no adhesion of fouling organisms such as shellfish and algae, and there is almost no slime.
○: Level at which fouling organisms such as shellfish and algae do not adhere, and slime is thin (appreciable to see the paint film surface) but can be gently wiped with a brush.
[Delta]: No fouling organisms such as shellfish and algae adhere, but the slime is so thick that the surface of the coating cannot be seen and cannot be removed even if wiped with a brush.
X: Level to which fouling organisms such as shellfish and algae are attached.

The details of the antifouling agents, pigments and other additives in Tables 3 to 4 are as follows.
Antifouling agent cuprous oxide (manufactured by Nisshin Chemco, NC-301, average particle size 3 μm)
Copper pyrithione (Arch Chemicals, Copper Omagine)
Zinc pyrithione (manufactured by Arch Chemicals, zinc omadin)
Sea Nine 211 (R & H, active ingredient 30% xylene solution)
Pigment Bengala (Toda Pigment, TODA COLOR EP-13D)
Talc (Matsumura Sangyo, Crown Talc 3S)
Zinc oxide (manufactured by Shodo Chemical, two types of zinc oxide (trade name))
Titanium oxide (Furukawa Machine Metal, FR-41)
Organic red pigment (Sanyo dye, Scarlet TR)
Other additives Tetraethoxysilane (manufactured by Kishida Chemical, special reagent grade)
Rosin zinc salt (50% xylene solution)
Hydrogenated rosin zinc salt (50% xylene solution)
Chlorinated paraffin Dispalon A603-20x (manufactured by Enomoto Kasei, fatty acid amide thixotropic agent)

From Tables 3 to 4, the coating films formed using the coating compositions of the present invention (Examples 1 to 11) were formed using the coating compositions of Comparative Examples 1, 3, 4, 6 and the like. The dissolved amount in seawater is maintained higher than the coating film, and in the antifouling test, there is no adhesion of fouling organisms such as shellfish and algae, and there is almost no adhesion of slime. Moreover, it turns out that the state of the dry coating film after completion | finish of a rotary test (after 6 months) is also favorable.
On the other hand, the coating film formed using the coating compositions of Comparative Examples 1 to 18 has a low dissolution amount in seawater and cannot prevent the attachment of fouling organisms, or the coating film may crack. However, each performance cannot be balanced.

Claims (6)

General formula (1):

Wherein R ¹ is a methyl group, R ² , R ³ and R ⁴ are selected from a branched alkyl group having 3 to 8 carbon atoms and a phenyl group, and may be the same or different. It is obtained by copolymerizing a mixture of a methacrylic acid triorganosilyl ester monomer (a) and a polymerizable unsaturated monomer (b) other than the monomer (a),
The monomer (b) contains methyl acrylate;
The content of the monomer (a) accounts for 25 to 65% by mass of the total mass of the monomer (a) and the monomer (b),
A copolymer for an antifouling coating composition, wherein the content of methyl acrylate occupies 25 to 75 mass% of the total mass of the monomer (a) and the monomer (b).   The total content of the monomer (a) and methyl acrylate accounts for 70% by mass or more of the total mass of the monomer (a) and the monomer (b). Copolymer. An antifouling paint composition comprising a copolymer and an antifouling agent,
The said copolymer is an antifouling paint composition which is a copolymer for antifouling paint compositions of Claim 1. An antifouling treatment method formed using the antifouling coating composition according to claim 3. The antifouling coating film which forms an antifouling coating film on the surface of a film formation thing using the antifouling paint composition of Claim 3. A coated product having the antifouling coating film according to claim 5 on a surface thereof.