JPH11228909A - Antifouling coating film, method for forming same, and structure coated with same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antifouling coating film excellent in intercoat adhesive strength, capable of markedly shortening a coating time, and desirable as an antifouling coating film for a cooling water passage for e.g. a power plant, a method for forming the same, and an antifouling structure coated with the same. SOLUTION: The antifouling coating film comprises (a) a polyurethane coating film prepared by applying and curing a polyurethane coating material containing a polyol and/or a polythiol and a polyisocyanate and (b) a topcoating film formed thereon and containing a resin component comprising a silicone polymer and/or a hydrolyzable-silyl-ester-group-containing acrylic copolymer. It is desirable that the film (a) is one formed by spraying and curing a polyurethane coating material containing a polyol and/or a polythiol and a polyisocyanate in the presence of an amine vapor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antifouling coating film, a method for forming the antifouling coating film, and a structure covered with the antifouling coating film. An antifouling coating which can be greatly shortened and is suitable as an antifouling coating for a cooling water channel of a power plant, a method for forming the antifouling coating, and an antifouling coated with the antifouling coating Related to the structure.

[0002]

BACKGROUND OF THE INVENTION In the sea, for example, barnacles, serpula, purple mussels, oysters, fusca, sea squirts,
A large number of plant and animal infested organisms such as Aonori and Aosa inhabit. Underwater structures installed in such seas, such as cooling water intake channels for thermal and nuclear power plants and other coastal plants, port facilities, offshore pipelines, offshore oilfield drilling rigs,
Marine organisms adhere to the surface of water-contacting parts such as buoys and mooring buoys and cause various damages when they grow. As an example, in the cooling water intake channel of a power plant, the resistance of flowing seawater for cooling increases due to the attachment and growth of marine organisms as described above, and as a result, the function of the heat exchanger is reduced and the power generation efficiency is reduced. Adversely affect. In addition, if the above-mentioned marine organisms attach to and grow on port facilities, submarine pipelines, oilfield drilling rigs, buoys, buoys, etc., the corrosion of the structural base material is promoted and the durability life of the structural base material is shortened. Sometimes.

[0003] In order to prevent or suppress such damages, various antifouling paints have been applied to the water-contacting surfaces of marine structures to prevent the growth of attached organisms.

However, in the conventional antifouling coating, undercoating, intermediate coating, and topcoating are performed in order to obtain sufficient interlayer adhesion strength and the like.
In order to secure the adhesion between the middle coat and the top coat, respectively, special primer coating and binder coating are performed, and a total of several coatings are performed, so a coating period of several days or more is required, However, there was a risk that sufficient painting could not be performed when the situation was imminent.

Therefore, antifouling paint can be applied to the water-contact surface of various underwater structures such as cooling water channels of power plants in a short period of time, and the adhesive strength between the surface of the structure (substrate) and the antifouling coating film is excellent. The appearance of antifouling coating films, methods for forming the same, and the like is desired.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the problems associated with the prior art as described above, and to prevent stains on the surface of a substrate to be coated, such as the water contact surface of an underwater structure, in a short time. It is an object of the present invention to provide an antifouling coating film which can be painted and thus can shorten the construction period, and is excellent in the adhesive strength between the substrate surface and the antifouling coating film, and a method for forming the same.

Another object of the present invention is to provide an antifouling structure coated with the above antifouling coating film.

[0008]

The antifouling coating film according to the present invention comprises a polyurethane coating film (a) obtained by coating and curing a polyurethane coating material containing a polyol and / or polythiol and a polyisocyanate, and the polyurethane coating film (a). ) Formed on the top coat (b) containing a silicone polymer and / or a hydrolyzable silyl ester group-containing acrylic copolymer as a resin component.

In the present invention, the polyurethane coating film
Preferably, (a) is a polyurethane coating formed by spraying and curing a polyurethane coating containing a polyol and / or polythiol and a polyisocyanate in the presence of an amine vapor.

The method for forming an antifouling coating film according to the present invention comprises:
(A) On at least one surface of the substrate, a polyurethane coating (a) obtained by coating and curing a polyurethane coating containing (B) a polyol and / or polythiol and a polyisocyanate is formed, and then (C) A) A top coat (b) containing a silicone polymer and / or a hydrolyzable silyl ester group-containing acrylic copolymer as a resin component is coated and cured on the polyurethane coat (a) to form a top coat (b). ) Is formed.

In the method for forming an antifouling coating film according to the present invention, the polyurethane coating film (a) comprises a polyurethane coating material containing a polyol and / or polythiol and a polyisocyanate in the presence of an amine vapor. It is preferably formed by spraying and curing.

The antifouling structure according to the present invention is a polyurethane coating containing (A) a substrate, and (B) a polyol and / or polythiol formed on at least one surface of the substrate and a polyisocyanate. And (C) a silicone-based polymer and / or a hydrolyzable silyl ester group-containing acrylic copolymer formed on the polyurethane coating (a). And a top coat (b) contained as a component.

In this antifouling structure, the polyurethane coating film (a) is coated with a polyol and / or
Alternatively, it is preferably formed by spraying and curing a polyurethane paint containing a polythiol and a polyisocyanate.

According to the present invention, the interlayer adhesion strength, that is, between the substrate and the polyurethane coating (a), and between the polyurethane coating (a) and the top coat (b) can be obtained without a primer treatment.
An antifouling coating film having excellent interlayer adhesion strength can be formed. Moreover, the polyurethane coating for the undercoat layer (a) can be cured in a very short time, and after the polyurethane coating (a) is formed, the polyurethane coating is directly and quickly applied to the surface of the polyurethane coating (a). Since the overcoat layer (b) having excellent adhesion strength to the film (a) can be formed, the coating period can be significantly reduced, and the anti-fouling film is suitable as an antifouling coating film for a cooling water channel of a power plant or the like. A soil coating is provided. According to the method for forming the antifouling coating film, the antifouling coating film can be obtained in a short time as described above. Further, according to the antifouling structure coated with the antifouling coating film, it is possible to prevent underwater organisms from being stained.

[0015]

DETAILED DESCRIPTION OF THE INVENTION The antifouling coating film according to the present invention will be specifically described below. [Antifouling coating] The antifouling coating according to the present invention comprises a polyurethane coating (a) and a topcoat (b) formed on the surface of the coating (a). a) is obtained by applying and curing a polyurethane paint containing a polyol and / or polythiol and a polyisocyanate, and a top coat (b) formed on this polyurethane coat (a) is used as a resin component. It contains a silicone-based polymer and / or a hydrolyzable silyl ester group-containing acrylic copolymer and an antifouling agent. In a preferred embodiment of the present invention, as described later, this top coat (b) contains a silicone-based polymer as an essential component, and further contains a hydrolyzable silyl ester group-containing acrylic copolymer as necessary. doing.

Such an antifouling coating film is usually provided so that the surface of the polyurethane coating film (a) is in close contact with the surface of the substrate to be coated, that is, the substrate to be coated / polyurethane coating film (a). / Top coat (b).

The substrate to be coated and the polyurethane coating
(a) and the top coat (b) will be described in this order. <Substrate to be coated> Examples of the substrate to be coated on which such an antifouling coating film is formed include cooling water intake and drainage channels of thermal power plants, nuclear power plants and other seaside plants, port facilities, submarine pipelines, Structures installed in the sea, such as offshore oil rigs, sea buoys, and mooring buoys, and structures installed in freshwater. The shape of the substrate to be coated is not particularly limited, such as a plate, a tube, a half tube, and a sphere, as long as it can be coated by a method described below.

Examples of the material of the substrate to be coated include metal, concrete, resin material, woody material, organic fiberboard, paper and the like. More specifically, as the metal, carbon steel, aluminum, stainless steel, copper,
Copper alloy, galvanized steel, zinc and the like can be mentioned.

Further, as the resin material, specifically, vinyl chloride, polyolefin (polyethylene, polypropylene), methyl methacrylate, polycarbonate, FRP (glass fiber reinforced plastics), CRP
(Carbon fiber reinforced plastics) and other hard materials, or vinyl chloride, polyolefin, vinylidene chloride, and the like. These plastic materials may be foamed or non-foamed. Among these various resin materials, carbon steel and concrete materials are preferable in terms of delamination strength between the substrate and the polyurethane coating film (a).

Prior to applying the polyurethane paint (a), the base material surface is preferably preliminarily subjected to a base treatment by the following method. That is, when the base material is a carbon steel material, the base pre-treatment of the base material is performed by removing mill scale, rust, and the like with a blast, a disk sander, a power brush, or the like, and then impregnating an organic solvent as necessary. The contaminants adhering to the substrate surface are removed with a rag. In the case of materials such as aluminum, stainless steel, and copper alloy, lightly roughen the surface of the substrate with a power brush, sandpaper, etc., and then use a cloth impregnated with an organic solvent as necessary. Wipe off dirt to clean the substrate surface.

When the base material is a concrete material, efflorescence, latence, etc. adhering to the surface of the base material are carefully removed with a disk sander, a power brush or the like, and then the base material surface is washed with fresh water. Cleanse,
Further, the adsorbed moisture is removed by natural drying or hot air drying so that the surface moisture becomes 10% by weight or less.

When the base material is a resin material, the surface of the base material is roughened by roughening the surface with an abrasive such as sandpaper, and then the base material is coated with a cloth impregnated with an organic solvent such as a lacquer thinner. The surface of the material is wiped off to clean the substrate surface.

If necessary, the surface of the base material is treated as described above, and then the polyurethane coating (a) is applied and cured to form the following polyurethane coating film (a) on the surface of the base material to be coated.

<Polyurethane coating film (a) (undercoat coating film)> The polyurethane coating film (a) is formed, for example, so as to be in intimate contact with the surface of the substrate to be coated. It is obtained by applying and curing a polyurethane paint (a) containing a polythiol and a polyisocyanate as a curing agent.

In a preferred embodiment of the present invention, the above-mentioned polyurethane coating film (a) is used in the presence of a vaporous amine catalyst.
It is obtained by coating and curing the above-mentioned polyurethane paint (a). As described above, when the polyurethane coating (a) is applied in the presence of the vaporous amine catalyst, the polyol (F1) and / or polythiol in the coating reacts with the polyisocyanate to form a urethane bond [—NH—C ( =
O)-] and> NH ·· between urethane bonds.
-It is considered that a hydrogen bond acts between O = C <and a secondary bonding force is generated to form a cured film that is tough, uniform in film thickness, and in close contact with the substrate to be coated.

Next, a method for forming such a polyurethane coating film (a) will be described. The method for forming the polyurethane coating film (a) is to form a uniform coating film on the substrate surface by curing the polyurethane coating material (a) on the substrate (substrate) in the presence of a vaporous amine catalyst. The method includes, for example, the following modes.

(1) A coating method in which a polyurethane paint (a) is sprayed or sprayed on a substrate with a spray gun in the presence of a vapor-form amine catalyst, and is rapidly cured to form a uniform coating film. (2) Polyurethane paint (a) is sprayed onto the substrate with a spray gun to form an uncured coating, and then the uncured coating is brought into contact with a vaporous amine catalyst to rapidly cure the coating. To form a uniform coating film.

(3) A coating method in which a polyurethane paint (a) is sprayed on a substrate with a spray gun and an amine catalyst is sprayed on the substrate with another spray gun to form a uniform cured coating.

(4) A method in which a polyurethane paint (a) is electrostatically applied in the presence of a vapor amine catalyst to form a uniform cured coating film. The electrostatic coating method will be described later in detail. In the present invention, among the above coating methods, the coating method (1) is particularly preferable.

Hereinafter, the amine catalyst used for such polyurethane coating and the polyurethane coating (a) will be sequentially described. <Amine catalyst> The amine catalyst used in the present invention is a tertiary amine, and specifically, trimethylamine, dimethylethylamine, triethylamine, tributylamine, dimethylbenzylamine, dimethylcyclohexylamine, dimethylethanolamine, diethylethanolamine, Examples include triethanolamine, pyridine, 4-phenylpropylpyridine, 2,4,6-collidine, quinoline, isoquinoline, N-ethylmorpholine, triethylenediamine and the like. Among them, dimethylethanolamine and triethylamine are preferably used.

When the amine catalyst is vaporized (sprayed), for example, a spray gun is used. The concentration of the vapor-form amine catalyst when the polyurethane paint (a) is spray-coated and cured by the above method can be set in a wide range of 20 to 4000 ppm. The preferred concentration of the vaporous amine catalyst is
500 to 2000 ppm.

For example, when a polyurethane paint (a) is atomized by a spray gun and sprayed onto a substrate in the presence of a vapor-form amine catalyst having a concentration of 200 to 4000 ppm, the polyurethane paint (a) is cured within a few minutes to form a uniform polyurethane coating. (a) is obtained.

Further, after the polyurethane coating (a) is spray-coated on the substrate to form an uncured coating film,
Exposure to ~ 4000 ppm of a vaporous amine catalyst rapidly cures the composition forming the uncured coating, resulting in a uniform coating within minutes.

Immediately before using the polyurethane coating (a), an amine catalyst may be added to the polyurethane coating (a) and spray-coated on a substrate to obtain a uniformly cured coating film. In this coating method, since the coating composition to which the amine catalyst has been added cures rapidly, it needs to be used in a short pot life and in a short time.

<Polyurethane Coating (a)> Polyol The polyurethane coating (a) is a substantially solvent-free or solvent-free coating. The polyurethane coating (a) contains a polyol and / or a polythiol as described above. And a polyisocyanate as a curing agent. Among the polyols, specifically, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol,
Dipropylene glycol, tripropylene glycol,
Polypropylene glycol, butylene glycol, dibutylene glycol, tributylene glycol, polybutylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,10-decanediol, alkanediol, cyclohexanedimethanol, etc. Glycerol, trimethylolpropane (TMP), 1,2,6-hexanetriol, trimethylolethane, 2,4-dihydroxy-3-hydroxymethylpentane, 1,1,1-tris (bishydroxymethyl ) Trihydric alcohols such as propane and 2,2-bis (hydroxymethyl) butanol-3; tetrahydric alcohols such as pentaerythritol and diglycerol; pentahydric alcohols (pentits) such as arabbit, ribitol and xylitol; , Galactito Hexahydric alcohols (hexit) such as
Polyglycol compounds having up to about 10 carbon atoms, such as polyvalent hydroxy compounds such as polytetramethylene glycol, and polyester polyols, epoxy polyols (alkanolamine-modified epoxy) derived from phthalic anhydride, sebacic acid, fatty acids, epoxy resins, etc. ),
Examples include polyether polyols and acrylic polyols.

Among them, ethylene glycol, propylene glycol, 1,6-hexanediol, glycerol, trimethylolpropane, pentaerythritol, polyester polyol and acrylic polyol are preferred.

Polythiol A polythiol (polymercapto compound) is a compound having two or more mercapto groups (-SH groups). As the polythiol, specifically, 1,3-propanedithiol, 1,4-butanedithiol, 1,6-hexanedithiol,
2,3-dimethylcaptopropanol, toluene-3,4-dithiol, α, α'-dimethylcapto-p-xylol, dimercaptoethane, diethylene glycol dimercaptan, triethylene glycol dimercaptan, dithiocatechol, 3-chlorothiocatechol , Dithioresorcin, dimercaptotoluene, xylylenedimercaptan, 1,3,5-trimercaptobenzene, dimercaptonaphthalene, didodecanedithiol, dithiolphenol, 4,4'-dithiophenol, 2,2'-dimethyl-4, 4'-thiodiphenol, dimercaptobenzothiazole, dithioerythritol and the like.

Specific examples of the polythiol other than the above include a complete ester or a partial ester composed of an aliphatic polyol and a mercapto lower fatty acid. As the aliphatic polyol, specifically, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol,
Dipropylene glycol, tripropylene glycol,
Polypropylene glycol, butylene glycol, dibutylene glycol, tributylene glycol, polybutylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,10-decanediol, alkanediol, cyclohexanedimethanol, etc. Glycerol, trimethylolpropane (TMP), 1,2,6-hexanetriol, trimethylolethane, 2,4-dihydroxy-3-hydroxymethylpentane, 1,1,1-tris (bishydroxymethyl ) Trihydric alcohols such as propane and 2,2-bis (hydroxymethyl) butanol-3; tetrahydric alcohols such as pentaerythritol and diglycerol; pentahydric alcohols (pentits) such as arabbit, ribitol and xylitol; , Galactito , Like hexavalent alcohols such allodulcite (hexites). Among them, glycerol, trimethylolpropane, and pentaerythritol are preferred.

Glycidyl ethers such as bisphenol A glycidyl ether, hydrogenated bisphenol A glycidyl ether, bisphenol F glycidyl ether, and novolak epoxy can also be used.

The above-mentioned mercapto lower fatty acids include, specifically, mercaptoacetic acid, mercaptopropionic acid, mercaptosalicylic acid, mercaptoglycolic acid, N- (2-hydroxyethyl) thioglycolic acid, mercaptosuccinic acid, mercaptomalic acid And the like. Among them, mercaptoacetic acid (HSCH ₂ COOH),
Mercaptopropionic acid is preferred.

The polythiols particularly preferably used in the present invention are esters having 2 to 4 mercapto groups consisting of pentaerythritol and mercaptoacetic acid or mercaptopropionic acid, or trimethylolpropane and mercaptoacetic acid or mercaptopropionic acid.

The thiol compound having one mercapto group can be used as a diluent or a plasticizer. In the present invention, it is not necessary to use a solvent, and it is desirable to use a polythiol having little or no odor.

[0043] The polyisocyanate polyisocyanates, specifically, hexamethylene diisocyanate (HDI), xylylene diisocyanate (XDI), 1,3-bis (isocyanatomethyl)
Cyclohexane (hydrogenated XDI, H6XDI), tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), 4,4-bis (isocyanatocyclohexyl) methane (hydrogenated MDI), naphthylene diisocyanate (NDI), isophorone diisocyanate ( IPDI), meta-xylylene diisocyanate (MX)
DI), lysine diisocyanate (2,6-diisocyanate methylcaproate) (LDI), methylcyclohexane-2,4 (or2,6) -diisocyanate (hydrogenated TDI)
r HTDI), trimethylhexamethylene diisocyanate (TMDI), dimer acid diisocyanate (DD
I), tolidine diisocyanate (TODI), p-phenylene diisocyanate, transcyclohexane-1,4
-Diisocyanates such as diisocyanate and tetramethyl xylene diisocyanate (TMXDI); triphenylmethane triisocyanate, tris (isocyanatephenyl) thiophosphate, lysine ester triisocyanate, 1,6,11-undecane triisocyanate, 1,8-diisocyanate Triisocyanates such as 4-isocyanate methyloctane, 1,3,6-hexamethylene triisocyanate, and bicycloheptane triisocyanate.

A nurate or an adduct derived from the above-described isocyanate can also be used. Specific examples of the polyisocyanate other than the above include the following carbodiimide-type polyisocyanates. This carbodiimide-type polyisocyanate has one or more -N = C = N- groups, and specifically, carbodiimide-type diphenylmethane diisocyanate, carbodiimide-type tolylene diisocyanate, carbodiimide-type dimethylbiphenylene diisocyanate,
Examples include carbodiimide-type xylylene diisocyanate, carbodiimide-type naphthalene diisocyanate, carbodiimide-type hexamethylene diisocyanate, carbodiimide-type isophorone diisocyanate, carbodiimide-type hydrogenated xylylene diisocyanate, and carbodiimide-type hydrogenated diphenylmethane diisocyanate.

Polyisocyanates preferably used in the present invention are carbodiimide-type diphenylmethane diisocyanate, carbodiimide-type tolylene diisocyanate, carbodiimide-type dimethylbiphenylene diisocyanate, and carbodiimide-type hexamethylene diisocyanate. Particularly, carbodiimide-type diphenylmethane diisocyanate is preferably used.

The carbodiimide type polyisocyanate having one -N = C = N- group can be represented by the following formula. ^{(OCN-R 1) -N =} C = N- (R 2 -NCO) [ in the formula ^{(OCN-R 1), (} R 2 -NCO) is a polyisocyanate. Further, specific examples of polyisocyanates other than the above polyisocyanates include (1) tri- or higher-valent aliphatic polyhydric alcohol (i), tolylene diisocyanate (TDI), and xylylene diisocyanate (X
DI), meta-xylylene diisocyanate (MXD
I), hexamethylene diisocyanate (HDI or H
MDI), isophorone diisocyanate (IPDI),
Or adduct with bis (isocyanatomethyl) cyclohexane (ii) and (2) hexamethylene diisocyanate (HDI or HMDI), isophorone diisocyanate (IPDI) or bis (isocyanatomethyl) cyclohexane, the following formula (I):

[0047]

Embedded image

An isocyanurate structure having a ring represented by the formula (nurate structure) can be mentioned. Specific examples of the trihydric or higher aliphatic polyhydric alcohol (i) used as a component of the adduct include glycerol, trimethylolpropane (TMP), 1,2,6-hexanetriol, trimethylolethane, Trihydric alcohols such as 2,4-dihydroxy-3-hydroxymethylpentane, 1,1,1-tris (bishydroxymethyl) propane and 2,2-bis (hydroxymethyl) butanol-3; pentaerythritol, diglycerol, etc. Pentahydric alcohols (pentit) such as arabic, ribitol and xylitol; and hexahydric alcohols (hexit) such as sorbit, mannitol, galactitol, allozurcit and the like. Among them, trimethylolpropane and pentaerythritol are particularly preferred.

Further, tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), metaxylylene diisocyanate (MXDI), hexamethylene diisocyanate (HDI or HMDI), isophorone diisocyanate (IPDI), Among bis (isocyanatomethyl) cyclohexane (hydrogenated XDI, H6 XDI) (ii), 1,3-bis (isocyanatomethyl) cyclohexane, tolylene diisocyanate (TDI) and xylylene diisocyanate (XDI) are preferred.

The adduct (1) used in the present invention is obtained by addition polymerization of the above-mentioned trihydric or higher aliphatic polyhydric alcohol (i) with bis (isocyanatomethyl) cyclohexane or the like (ii). can get.

The adduct preferably used in the present invention includes, for example, compounds represented by the following formulas. (1) Adduct of TMP and hydrogenated XDI CH ₂ O—CO—NH—CH ₂ —R—CH ₂ —NCO CH ₃ CH ₂ —C—CH ₂ O—CO—NH—CH ₂ —R—CH ₂ —NCO CH ₂ O—CO—NH—CH ₂ —R—CH ₂ —NCO [R in the formula: 1,3-cyclohexylene group] (2) Adduct of pentaerythritol and hydrogenated XDI C [CH ₂ O _{-CO-NH-CH 2 -R-} CH 2 -NC
O] ₄ [R in the formula: 1,3-cyclohexylene group] The isocyanurate structure (nurate structure) used as the polyisocyanate in the present invention has a ring represented by the formula (I) in the molecule. It has one or two or more.

The isocyanurate structure used in the present invention is, for example, bis (isocyanatomethyl)
It can be obtained by performing a trimerization reaction, a pentamerization reaction, and a heptamerization reaction of cyclohexane (hydrogenated XDI, H6 XDI).

<Blending Ratio> In the present invention, each component of the polyol and / or polythiol and the polyisocyanate contained in the polyurethane coating material (a) is equivalent to the isocyanate group contained in the polyisocyanate and the hydroxyl group contained in the polyol. The ratio of the equivalent and the total equivalent of the thiol groups contained in the polythiol [NCO group / (O
H group + SH group)] is usually 0.1 to 5, preferably 0.2
To 4, more preferably 0.5 to 3, particularly preferably 0.7 to 2.

When a carbodiimide-type polyisocyanate as described above is used in combination with a polyisocyanate other than the carbodiimide-type isocyanate, the carbodiimide-type isocyanate is usually used in an amount of 100 parts by weight based on the total amount of these polyisocyanates. It is used in an amount of 1 part by weight to less than 200 parts by weight, preferably 5 parts by weight to less than 150 parts by weight, more preferably 20 parts by weight to less than 100 parts by weight.

When the carbodiimide-type polyisocyanate is used in the above amount, a polyurethane coating which can be rapidly cured to form a coating film can be obtained. The polyurethane coating (a) can form a clear coating film by using as a clear coating containing no pigment or the like,
Conventionally known paint additives such as color pigments and dispersants may be blended within a range that does not impair the object of the present invention.

The polyurethane paint (a) containing the above-mentioned polyol and / or polythiol and polyisocyanate has a long pot life and is easy to handle. Next, the electrostatic coating method of the polyurethane paint (a) having such a composition will be described in detail.

When the polyurethane coating (a) is electrostatically applied, the viscosity of the polyurethane coating (a) is not particularly limited as long as the viscosity allows the electrostatic coating.
It is 0 cPs or less, preferably 300 cPs or less, particularly preferably 100 cPs or less (measured with a B-type viscometer).
Such a low-viscosity polyurethane coating (a) tends to be finely atomized into fine particles, and is suitable for low-pressure, low-flying-speed electrostatic spray coating. Improvement can be achieved.

The electric resistance of the polyurethane coating (a) used in the present invention is usually about 30 to 100 MΩ. Polyurethane paint (a) having such an electric resistance value,
Finely atomized by injection.

In electrostatic coating, a high voltage is applied by using a grounded object as an anode (+) and a paint spraying device as a cathode (-) to form an electrostatic field between the two electrodes, and paint is applied in the electrostatic field. This is a method of forming a coating film on the surface of an object to be coated by causing the substrate to be scattered, charged negatively and sucked by a substrate (substrate to be coated).

When the polyurethane coating (a) is electrostatically coated, for example, as a heavy-duty anticorrosion coating, a sufficient and uniform film can be formed on the edges of steel plates of steel structures such as ships, edges such as holes, and narrow portions. A thick coating film can be formed. Therefore, according to this electrostatic coating method, additional coating by hand brushing of edges and narrow portions, which is required by simple airless spray coating using a conventional tar-based anticorrosion coating, is unnecessary. Thus, the number of steps can be reduced.

The above-mentioned electrostatic coating method has the following modes. (i) A coating method in which a low-viscosity polyurethane coating material (a) is applied to an object to be coated by an electrostatic coating method and rapidly cured in the presence of a vaporous amine catalyst to form a coating film.

(Ii) The polyurethane coating (a) is applied to an object to be coated by an electrostatic coating method to form an uncured coating film, and the uncured coating film is brought into contact with a vapor amine catalyst to form an uncured coating film. A method of curing a coating film rapidly to form a coating film.

(Iii) The polyurethane paint (a) is sprayed from one paint spraying device (for example, a spray gun) by the electrostatic spraying method and adhered to the object to be coated, and at the same time, the amine catalyst is sprayed from the other spraying device. A coating method in which a cured coating film is formed by spraying the coating material on the substrate.

Among these electrostatic coating methods, in particular, the above (i)
The electrostatic coating method of ii) is preferred. The electrostatic coating device used for the electrostatic coating, the coating conditions, and the like will be described in further detail.

For such electrostatic coating, any of a fixed (automatic) coating apparatus and a portable (hand-held) coating apparatus can be used. Cup electrode type and rotary disk type are mentioned.

Of these, a portable coating apparatus using a spray gun is preferably used when painting vessels (objects to be coated) such as tankers, fishing boats, and passenger boats because of its excellent workability in a narrow environment.

The distance between the object to be coated and the cathode during the electrostatic coating, the applied DC high voltage value, the feed pressure of the paint, the air pressure of the paint spray, and the like depend on the type of paint used, its viscosity, and necessity. It can be appropriately set depending on the film thickness to be performed, the moving speed of the coating apparatus, and the like, and is not particularly limited.

In a portable (hand-held) coating apparatus, a cathode is set at the tip of a spray gun, and when a trigger is triggered, a negative charge is given to the sprayed paint particles, and a coating object separated by several to several tens cm is provided. Electrostatic painting is possible. The power supply voltage may be low, and the spray gun is easy to carry, so it is suitable for, for example, on-site painting of a hull or the like. In addition, examples of the spray gun include an air atomizing type, an airless atomizing type, an electrostatic atomizing type (rotating cup type), and the like.
Either method may be adopted.

In the grid type coating, 30 to 200 k
V (preferably 65 to 110 kV) is applied, and the distance between the object to be coated and the grid (cathode grid frame) is set to 10 to 10 V.
100 cm (preferably about 30 to 50 cm), and at the time of air spraying, spray air pressure is 0.5 to 5 kg / cm.
² (preferably 1.5 to 2.5 kg / cm ² ), a paint feed pressure of 0.2 to ² kg / cm ² , a secondary pressure (paint pressure) of 50 to 300 kg / cm ² during airless spraying, and a moving speed of 20. ~ 200 cm / sec (preferably 40-90 cm /
Seconds).

In the rotating cup type, the rotation speed is 300 to 3
000 rotations / minute (preferably 750 to 1800 rotations / minute)
Minute), the paint is fed into the rotating cup (cathode) held therein, and the object to be coated can be electrostatically coated with an applied voltage of about 50 to 70 kV. Easy.

In any case, the surrounding wind speed at the time of coating is preferably as small as possible from the viewpoint of paint loss and painted skin, and is preferably 0.3 m / sec or less. When an electrostatic coating of an object to be coated is performed by such a method, the use of an automatic coating system such as a robot coating is particularly effective in reducing the number of work steps.

<Coating film (b)> The above polyurethane coating film (a)
As the antifouling coating composition for the top coat (b) formed on the surface, specifically, [i] a reaction-curable silicone rubber, particularly a room-temperature-curable (RTV) silicone rubber as a vehicle; ii] does not react with this reaction-curable silicone rubber,
And, a water-repellent organic compound having good compatibility and dispersibility,
If necessary, a non-toxic antifouling paint composition comprising [iii] a hydrolyzable silyl group-containing acrylic copolymer resin may be mentioned.

The reaction-curable silicone rubber [i] is mainly composed of an organopolysiloxane having a siloxane bond, which is cured by a chemical reaction. The organopolysiloxane has a hydroxyl group as a curing reactive functional group.
It has an alkoxyl group and the like, and a methyl group, a phenyl group, a vinyl group and the like as an organic group are directly bonded to Si.

Further, a polyfunctional silane compound having a hydrolyzable group bonded thereto can be used as a crosslinking agent. Examples of the hydrolyzable group include an acetoxy group, a methoxy group, a ketoxime group, an enoxy group, and an amide group. Further, metal organic acid salts, peroxides, organic amines and the like can be used as a curing catalyst. Examples of the metal organic acid salts include naphthenates such as lead, iron, cobalt, manganese, and zinc, and octylates.

By blending at least one of them with the above-mentioned organopolysiloxane, a one-pack or two-pack silicone rubber can be obtained. These are cured by hydrolysis, dealcoholization, deacetic acid, deoxime, dehydroxylamine reaction, etc. at room temperature or by heating, but are one-pack type silicone rubber that cures at room temperature due to ease of coating workability. Are preferable, and those having little irritation of by-products generated at the time of curing are most preferable.

More specifically, as applicable products,
KE40RTV, KE48, KE42S, KE45, K
E45TS, KE445, KE348 (all manufactured by Shin-Etsu Chemical Co., Ltd., trade names) and the like can be used.

The water-repellent organic compound [ii] includes, for example, silicone oil, mineral oil, petroleum wax, plasticizer, fatty oil, fluorine oil and the like. Of these, any liquid or grease at room temperature can be used, but silicone oil is particularly preferred. As the silicone oil, any one of methyl silicone oil, methylphenyl silicone oil and polyether-modified silicone oil can be used alone or in combination.

These silicone oil equivalents include KF-96, KF-92, KF-69 (above methyl silicone oil), KF-50, KF-53, and KF-96.
54, KF-56 (above methylphenyl silicone oil), KF-351, KF-353 (polyether-modified silicone oil) (all manufactured by Shin-Etsu Chemical Co., Ltd., trade names) and the like can be used. The mixing ratio of the water-repellent organic compound to the reaction-curable silicone rubber is 1 to 1 with respect to the solid content of the reaction-curable silicone rubber.
It is 50% by weight, preferably 5-35% by weight. If the mixing ratio is less than 1% by weight, the antifouling performance decreases, and if it exceeds 50% by weight, the curability of the coating film is poor and a durable coating film cannot be obtained.

As the above-mentioned hydrolyzable silyl group-containing acrylic copolymer resin [iii] to be blended as required, conventionally known ones are widely used, and in particular, (i) (meth)
The copolymer [I] of an alkyl acrylate and (ii) at least one monomer selected from (meth) acrylic acid and a hydroxy lower alkyl (meth) acrylate is subjected to acetoxy as a hydrolyzable group. A hydrolyzable silyl group-containing copolymer obtained by reacting a silane compound containing a group, a ketoxime group or an alkoxy group is preferred.

The copolymer [I] comprises (i)-(1)
(Meth) acrylic acid alkyl ester, and (i)-
(2) A vinyl compound selected from vinyl acetate, vinyl chloride, vinyl methyl ether, vinyl ethyl ether and vinyl pyrrolidone, and (ii) at least one selected from (meth) acrylic acid and hydroxy lower alkyl (meth) acrylate. It may be a copolymer with a kind of monomer.

Examples of the alkyl (meth) acrylate include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, octyl acrylate (the above alkyl groups may be linear or branched) and methacrylic compounds corresponding thereto. For example, methyl methacrylate is exemplified.

Examples of the vinyl compound include vinyl acetate, vinyl chloride, vinyl methyl ether, vinyl ethyl ether, vinyl pyrrolidone and the like. Examples of the hydroxy lower alkyl (meth) acrylate include 2-hydroxyethyl (meth) acrylate and 2-hydroxyethyl (meth) acrylate.
Examples include hydroxypropyl (meth) acrylate.

Examples of silane compounds containing an acetoxy group, a ketoxime group or an alkoxy group as a hydrolyzable group include methyltriacetoxysilane, vinyltriacetoxysilane, ethyltriacetoxysilane, tris (ethylmethylketoxime) methylsilane, tris (Ethylmethylketoxime) vinylsilane, vinyltrimethoxysilane, ethyltrimethoxysilane, hexyltrimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, vinyltriethoxysilane, ethyltriethoxysilane, propyltriethoxysilane,
Examples include phenyltriethoxysilane, methyltripropoxysilane, and methyltriisopropoxysilane.

The hydrolyzable silyl group-containing acrylic copolymer resin [iii] comprises (i) at least one monomer selected from alkyl (meth) acrylates and vinyl compounds, and (ii) (meth) ) A copolymer [I] obtained by radical polymerization of at least one monomer selected from acrylic acid and hydroxy lower alkyl (meth) acrylate in the presence of an organic solvent, as a hydrolyzable group It can be obtained by reacting a silane compound containing an acetoxy group, a ketoxime group or an alkoxy group.

In this reaction, when the (meth) acrylic acid was used as the active group ((ii)) of the copolymer [I], it was a carboxyl group, and a hydroxy lower alkyl (meth) acrylate was used. Hydroxyl group in the case)
Then, it is considered that a silane compound having a hydrolyzable group will react.

The amount of (i) the alkyl (meth) acrylate monomer used in producing the copolymer [I], and (ii) (meth) acrylic acid and hydroxy lower alkyl (meth) acrylic acid The amount of at least one monomer selected from esters, and further the amount of the silane compound having a hydrolyzable group, are mixed with the hydroxyl group of the obtained hydrolyzable silyl group-containing acrylic copolymer after hydrolysis. It is preferably determined in consideration of the surface orientation balance of the hydrophobic methyl groups of the reaction-curable silicone rubber.

In general, (ii) (meth) acrylic acid or hydroxy lower alkyl (meth) acrylate is used in an amount of 1 to 30% by weight, preferably 2 to 20% by weight in the copolymer [I]. It is preferably polymerized.

The silane compound having a hydrolyzable group is used in an amount equal to or more than the amount of (ii) (meth) acrylic acid or hydroxy lower alkyl (meth) acrylate in the copolymer [I]. Preferably.

(Ii) (meth) acrylic acid or hydroxy lower alkyl (meth) acrylate is 1 to 3
If it is not 0% by weight, the surface orientation balance between the hydrolyzed hydroxyl group of the hydrolyzable silyl group-containing acrylic copolymer and the hydrophobic methyl group of the silicone rubber is not appropriate, and the hydrolysis of the silicone rubber is not sufficient. Since the degradable silyl group-containing acrylic copolymer must be excessively mixed, the water repellency of the surface is poor and the antifouling property may be reduced.

The hydrolyzable silyl group-containing acrylic copolymer resin [iii] has a number average molecular weight of 3,000 to 3,
It is preferably in the range of 0000. When the number average molecular weight is less than 3,000, sufficient coating film strength cannot be obtained. If it exceeds 30,000, the compatibility with the silicone rubber is poor.

The mixing ratio of the hydrolyzable silyl group-containing acrylic copolymer resin to the silicone rubber is 0.1 to 35% by weight, generally 1 to 35% by weight, based on the silicone rubber solids.
20% by weight is preferred. When the content is less than 0.1% by weight or more than 35% by weight, the antifouling property is inferior.

The antifouling paint composition for the non-toxic top coat (b) may contain, if necessary, an extender pigment, a coloring pigment, an anticorrosion pigment, a sagging agent, A stain, an organic solvent, a plasticizer, and the like may be contained.

To form the top coat (b) comprising the antifouling paint composition on the surface of the polyurethane coat (a), brush coating, spray coating (air spray, airless spray), roll coater coating, A conventionally known method such as immersing the substrate to be coated on which the polyurethane coating film (a) is formed in the top coating material (b) may be appropriately employed.

The dry film thickness of the antifouling coating film thus obtained is determined in consideration of antifouling / anticorrosion life, cost, and the like, which are expected in the object to be coated or the antifouling structure.
Usually, the polyurethane coating (a) has a thickness of 5 to 5000 μm, preferably 100 to 2000 μm, and the top coating (b)
The thickness is 20 to 500 μm, preferably 50 to 200 μm.

The antifouling coating film as described above is applied to the surface of the substrate to be coated on the substrate to be coated / polyurethane coating (polyurethane layer).
In the antifouling structure in which each coating or each layer is provided in the order of (a) / coating coating (coating layer) (b), a polyurethane coating (a) is applied between the substrate to be coated and the polyurethane coating (a). Membrane (a) and top coat
(b) is excellent in interlayer adhesive strength, and since there is no need to provide a primer layer or a binder layer between these coating films (layers), the coating operation can be completed in a short time. Moreover, in such an antifouling structure, even if the antifouling structure comes into contact with fresh water or seawater, biological fouling on the contact surface is prevented.

Further, a polyurethane paint (a) as an undercoat paint used for producing such an antifouling structure.
Since it cures in an extremely short time, the top coat (b) can be quickly applied directly after the formation of the polyurethane coating (a), thus shortening the coating process and shortening the number of coating days. Can be.

The antifouling structure includes, for example,
Antifouling wall panels that are detachably attached to the water contact surface of underwater structures, cooling water intake and drainage channels for thermal and nuclear power plants and other coastal plants, port facilities, submarine pipelines, offshore oilfield drilling rigs, Structures installed in the sea, such as sea buoys and buoys for mooring ships, and structures installed in freshwater, etc., and other ships, etc.

[0098]

According to the present invention, the interlaminar adhesive strength without the primer treatment, that is, between the substrate and the polyurethane coating (a), and between the polyurethane coating (a) and the topcoat (b)
An antifouling coating film having excellent interlayer adhesion strength can be formed. As described above, when forming the antifouling coating film of the present invention, since it is not necessary to perform primer treatment on the surface of the substrate to be coated or binder coating on the surface of the polyurethane coating film (a) in advance, the underwater structure The antifouling coating can be performed in a short time on the surface of the substrate to be coated, such as the surface in contact with water, and is suitable as an antifouling coating film for cooling water passages in power plants and the like.

According to such a method for forming an antifouling coating film, an antifouling structure coated with the antifouling coating film in a short time is provided. Further, according to the antifouling structure coated with the antifouling coating film, it is possible to prevent underwater organisms from being stained.

[0100]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

The components used for preparing the coating compositions used in the following Examples and Comparative Examples, as well as their compositions, physical properties, manufacturers and distributors, are as follows. (1) PETP polymercapto compound, manufactured by Yodo Chemical Co., Ltd., pentaerythritol tetrakisthiopropionate, equivalent of SH group = 136.

(2) OTG polymercapto compound, manufactured by Yodo Chemical Co., Ltd., octyl thioglycolate, equivalent of SH group = 204.

(3) Necils EPX-L Polymercapto compound, trade name "Necils EPX-L" manufactured by AC Japan.

(4) MTL carbodiimide-type diphenylmethane diisocyanate,
Nippon Polyurethane Industry Co., Ltd., trade name "Millionate MTL", NCO content = 28.9%.

(5) 170HN HDI-based isocyanurate manufactured by Takeda Pharmaceutical Co., Ltd., trade name “Takenate D170HN”, NCO content = 2
1.0%.

(6) DER671-X75 epoxy resin varnish (containing 25% by weight of xylene), manufactured by Dow Chemical Company, trade name "DER671-X75", epoxy equivalent to resin solid content = 425-550.

(7) TD-966 Polyamide resin (nonvolatile content: 60%), manufactured by Dainippon Ink and Chemicals, Inc., trade name “Lacamide TD-966”.

(8) VAGD Vinyl resin, manufactured by Union Carbide, trade name "VAG
D ", molecular weight = about 15,000.

(9) Talc: “Talc NKK” (trade name, manufactured by Fuji Talc Kogyo KK)
Average particle size = 6-8 μm.

(10) Barium sulfate (trade name: Barium sulfate BA, manufactured by Sakai Chemical Industry Co., Ltd.) (11) Titanium white, product name “TR-92”, manufactured by Thai Oxide.

(12) Polyamide wax “ASA-T350F” manufactured by Ito Oil Co., Ltd. (13) Colloidal silica "Aerosil 20" manufactured by Nippon Aerosil Co., Ltd.
0 ", specific surface area = 200 m ² / g (BET method).

(14) KE-445 Silicone-liquid RTV rubber, manufactured by Shin-Etsu Chemical Co., Ltd.
Product name “KE-445T”, viscosity = 50 poise (25
° C).

(15) TSE389 silicone-liquid RTV rubber, Toshiba Silicone Co., Ltd.
Manufactured by TSE389-C, trade name, viscosity = 56 poise (25 ° C.).

(16) KF-96 dimethyl silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd., trade name "KF-96-100", viscosity = 100 cSt (2
5 ° C).

(17) TSF4300 Methylphenyl silicone oil, manufactured by Toshiba Silicone Co., Ltd., trade name “TSF4300”, viscosity = 140c
St (25 ° C.).

The coating materials used in the following Examples and Comparative Examples and their preparation methods are as follows. <Coating composition 1 (for undercoating)> As shown in Table 1 below, 22.4 parts by weight of PETP, OT
G 4.3 parts by weight, Nesils EPX-L 9.6 parts by weight, talc 27.7 parts by weight, titanium white 8 parts by weight, barium sulfate 13.8 parts by weight, colloidal silica 0.8 parts by weight, methyl isobutyl ketone 13. 4 parts by weight were charged into a steel container, and dispersed with a high-speed disper for 1 hour to obtain Agent A of the coating composition 1.

Next, 33.3 parts by weight of MTL, 170 HN
66.7 parts by weight were charged into a steel container and dispersed with a high speed disperser for 10 minutes to obtain Agent B of coating composition 1.
Before painting, the weight ratio (A / B) of the A agent and the B agent is 59.2 / 4.
The mixture was mixed at 0.8 to obtain a coating composition 1.

<Coating composition 2 (for undercoating)> As shown in Table 1 below, 18.1 parts by weight of PETP, OT
G3 parts by weight, Nesils EPX-L 22.6 parts by weight, talc 26.1 parts by weight, titanium white 7.5 parts by weight, barium sulfate 13 parts by weight, polyamide wax 0.8 parts by weight, methyl isobutyl ketone 8.9 parts by weight The part was charged into a steel container and dispersed with a high-speed disper for 1 hour to obtain Agent A of the coating composition 2.

Next, 25 parts by weight of MTL, 170 HN75
A part by weight was charged into a steel container and dispersed with a high-speed disper for 10 minutes to obtain Agent B of coating composition 2. Before coating, Agent A and Agent B were mixed in a weight ratio (A / B) of 66.1 / 33.9 to obtain a coating composition 2.

<Coating composition 3 (for undercoating)> As shown in Table 1 below, 35 parts by weight of DER671-X75, 35 parts by weight of talc, 10 parts by weight of titanium white, 2 parts by weight of amide wax, 11 parts by weight of xylene Parts, 7 parts by weight of methyl isobutyl ketone were charged into a steel container, and dispersed with a high speed disper for 1 hour to obtain Agent A of coating composition 3.

Before coating, the agent A of the coating composition 3 and the agent B
Agent (TD-966) in a weight ratio (A / B) of 88.5 /
The mixture was mixed at 11.5 to obtain a coating composition 3. <Coating composition 4 (for undercoating)> As shown in Table 1 below, 15 parts by weight of VAGD was dissolved in 50 parts by weight of a mixed solution obtained by mixing xylene / methyl isobutyl ketone at a weight ratio of 1/1. To the varnish,
15 parts by weight of talc, 10 parts by weight of titanium white, 2 parts by weight of amide wax, 4 parts by weight of xylene, and 4 parts by weight of methyl isobutyl ketone were charged into a steel container and dispersed for 1 hour with a high speed disperser. (A agent only)
I got

<Top coating composition 1> 100 parts by weight of KE-445 and 20 parts of KF-96
A steel container was charged in an amount of part by weight, and dispersed in a high-speed disper for 10 minutes to obtain a top coating composition 1.

<Top Coating Composition 2> 100 parts by weight of TSE389 and 20 parts by weight of TSF4300 were charged into a steel container and dispersed with a high speed disperser for 10 minutes to obtain a top coating composition 2.

[0124]

[Table 1]

[0125]

Example 1 A coating composition 1 for undercoating as shown in Table 1 was sprayed on a sandblasted plate of 100 × 300 × 2.3 mm under a dimethylethanolamine vapor catalyst so that the dry film thickness became 200 μm. It was applied to give an undercoat coating film 1. In the above coating, the amine vapor concentration is
The coating was performed with the setting within the range of 800 to 1000 ppm. The amine vapor concentration was measured with a Kitagawa amine detector tube manufactured by Komei Rikagaku Kogyo KK.

Then, after 10 minutes, the top coat 1 containing a silicone polymer as a resin component was applied to the surface of the undercoat 1 so as to have a dry film thickness of 100 μm. A body (painted plate) was obtained. That is, in this example, the number of times of recoating is a total of two times of the undercoat coating composition 1 and the top coating composition 1, and the coating interval required for coating is 10 minutes.

The above coating steps are shown in Table 2. Also,
Table 3 also shows the time required to complete the antifouling structure calculated based on the number of coatings and the coating time interval required for the coating.
Shown in

The coated plate was dried at room temperature (20 ° C.) for 7 days, attached to an immersion raft, immersed in the sea at a depth of 1 m, and evaluated for antifouling performance and adhesion after 6 and 12 months. Was done.

The evaluation criteria are as follows. <Antifouling performance> The antifouling performance was evaluated by the state of adhesion of marine organisms (the area of adhesion of marine organisms per unit area) on the surface of the coating film of the coated plate after immersion.

<Evaluation Criteria for Adhesion> A cut was made with a knife on the surface of the coating film of the coated plate after immersion in the sea. did. "Good": Peeling does not occur even when a knife is inserted. "Slightly poor": When a knife is put on the surface of the coating film of the coated plate in the same manner as described above, "floating" occurs in the coating film, but the coating film is not completely peeled off. "Defective": When a knife is put on the surface of the coating film of the coated plate in the same manner as described above, the entire surface is peeled off.

<Evaluation Results> As a result of the evaluation of the coated plate, as to the antifouling property, slight adhesion of slime to the coating film surface of the coated plate was observed 6 months after immersion in the sea, and 12 months later. Slime adherence was observed. Regarding the coating film adhesion, after immersion in the sea, after 6 months and 12 months,
Even when the blade edge of the knife was inserted into the cross cut portion of the coating film surface with the cutter knife, no peeling occurred, and the adhesion of the coating film was “good”.

Table 4 also shows the results.

[0133]

Example 2 Example 1 was repeated except that coating composition 2 was used in place of coating composition 1 as the undercoat.

In this example, the number of times of coating was two, and the coating interval required for coating was 10 minutes. Both the antifouling property of the obtained antifouling structure and the adhesion of the coating film were as good as in Example 1.

Tables 2 to 4 also show the coating process, coating man-hours, coating intervals, coating film antifouling properties, and coating film adhesion evaluations.

[0136]

Example 3 In Example 1, except that the paint composition 2 was used instead of the paint composition 1 as the undercoat paint, and the topcoat paint composition 2 was used instead of the topcoat paint composition 1 as the topcoat paint. In the same manner as in Example 1.

In this example, the number of times of coating was two, and the coating interval required for coating was 10 minutes. Both the antifouling property of the obtained antifouling structure and the adhesion of the coating film were as good as in Example 1.

Tables 2 to 4 also show the coating process, the number of coating steps, the coating interval, the antifouling property of the coating film, and the evaluation of the adhesion of the coating film.

[0139]

Comparative Example 1 Zinc epoxy-based shop primer [China Paint Co., Ltd., trade name: “Epicon Zinc Rich Primer-B-2”] was applied to the same sand blast plate as used in Example 1 in a dry film thickness. After pre-coating to a thickness of 15 μm, after 16 hours, the undercoat coating composition 3 as shown in Table 1 was subjected to ordinary spray coating so that the dry film thickness was 200 μm, to obtain an undercoat coating 3. Was.

After 8 hours, the surface of the undercoat 3 was coated with the same top coating composition 1 as in Example 1 so that the dry film thickness was 100 μm. ) Got. That is, in this comparative example, the number of times of recoating was a total of three times of the zinc epoxy-based shop primer, the undercoat coating composition 3 and the top coating composition 1, and the coating interval required for coating was 24 hours in total. Was.

As a result of the evaluation of the coated plate, as for the antifouling property, a slight adhesion of slime to the surface of the coated plate was observed 6 months after immersion in the sea, and 10% of barnacles after 12 months. And 20% of Aonori were adhered. The coating film adhesion was "slightly poor" after 6 months of immersion in the sea, and "poor" after 12 months.

Tables 2 to 4 also show the coating process, the number of coating steps, the coating interval, the antifouling property of the coating film, and the evaluation of the adhesion of the coating film.

[0143]

COMPARATIVE EXAMPLE 2 In Comparative Example 1, eight hours after the undercoating film 3 was applied, an epoxy resin intermediate coating having excellent adhesion to the following top coating composition 1 containing a silicone polymer as a resin component. Paint [China Paint Co., Ltd., product name "Epicon H"
B-AL binder ”] so as to have a dry film thickness of 100 μm.

Next, 10 hours after the application of the binder, the top coating composition 1 was applied in the same manner as in Comparative Example 1 so as to have a dry film thickness of 100 μm. I got That is, in this comparative example, the number of times of coating was 4 in total of the zinc epoxy-based shop primer, the undercoating paint composition 3, the binder and the topcoating paint composition 1.
This was a time, and the coating interval required for coating was 34 hours in total.

As a result of the evaluation of the coated plate, as for the antifouling property, slight adhesion of slime to the coated film surface of the coated plate was observed both 6 months and 12 months after immersion in the sea. The coating film adhesion was “good” both after 6 months and 12 months after immersion in the sea.

Tables 2 to 4 also show the coating process, coating man-hours, coating intervals, coating film antifouling properties, and coating film adhesion evaluations.

[0147]

Comparative Example 3 Comparative Example 1 was carried out in the same manner as in Comparative Example 1 except that a top coat composition 2 was applied instead of the top coat composition 1 as the top coat.

That is, in this comparative example, the number of times of application was three times in total of the zinc epoxy-based shop primer, the undercoat paint composition 3 and the topcoat paint composition 2, and the coating interval required for painting was 24 in total. It was time.

As a result of the evaluation of the coated plate, as for the antifouling property, 5% of Aonori was found to adhere to the surface of the coated film of the coated plate 6 months after immersion in the sea, and 20% after 12 months. And 30% of Aonori were adhered. The coating film adhesion was “poor” both 6 months and 12 months after immersion in the sea.

Tables 2 to 4 also show the coating process, the number of coating steps, the coating interval, the antifouling property of the coating film and the evaluation of the adhesion of the coating film.

[0151]

Comparative Example 4 Comparative Example 1 was carried out in the same manner as Comparative Example 1 except that the undercoat paint composition 4 was applied instead of the undercoat paint composition 3 as the undercoat paint.

That is, in this comparative example, the number of times of coating was three times in total of the zinc epoxy-based shop primer, the primer coating composition 4 and the top coating composition 1, and the coating interval required for coating was a total of 20 times. It was time.

As a result of the evaluation of the coated plate, as for the antifouling property, 5% of barnacles and 10% of Aonori were adhered to the surface of the coated film of the coated plate 6 months after immersion in the sea. , 25% of barnacles and 30% of Aonori were observed. The coating film adhesion was “poor” both 6 months and 12 months after immersion in the sea.

Tables 2 to 4 also show the coating process, the number of coating steps, the coating interval, the antifouling property of the coating film and the evaluation of the adhesion of the coating film.

[0155]

[Table 2]

[0156]

[Table 3]

[0157]

[Table 4]

──────────────────────────────────────────────────の Continuation of front page (51) Int.Cl. ⁶ Identification symbol FI C09D 183/04 C09D 183/04 // C08G 18/48 C08G 18/48 Z 18/50 18/50 Z (72) Inventor's hand Masayasu Hanabe 7 in Meiji Shinkai 1 in Chugoku Coating Co., Ltd., Otake City, Hiroshima Prefecture (72) Inventor Koji Morimoto 2306 No. 2 Mikami, Yasu-cho, Yasu-gun, Shiga 7 In Chugoku Paint Co., Ltd.

Claims (6)

[Claims] 1. A polyurethane coating (a) obtained by applying and curing a polyurethane coating containing a polyol and / or polythiol and a polyisocyanate, and a silicone-based coating formed on the polyurethane coating (a). Coating and / or hydrolytic type silyl ester group-containing acrylic copolymer containing as a resin component a top coat (b)
An antifouling coating consisting of: 2. The polyurethane coating (a) is a coating formed by spraying and curing a polyurethane coating containing a polyol and / or polythiol and a polyisocyanate in the presence of amine vapor. The antifouling coating film according to claim 1. 3. A polyurethane coating (a) formed by applying and curing a polyurethane coating containing (B) a polyol and / or polythiol and a polyisocyanate on at least one surface of a substrate (A). Thereafter, (C) a topcoat containing a silicone polymer and / or a hydrolyzable silyl ester group-containing acrylic copolymer as a resin component is applied and cured on the polyurethane coating (a). A method for forming an antifouling coating film, wherein b) is formed. 4. The polyurethane coating (a) is a coating formed by spraying and curing a polyurethane coating containing a polyol and / or polythiol and a polyisocyanate in the presence of amine vapor. The method for forming an antifouling coating film according to claim 3. 5. A substrate comprising: (A) a substrate; and (B) a substrate formed on at least one surface of the substrate.
A polyurethane coating (a) obtained by applying and curing a polyurethane coating containing a polyol and / or polythiol and a polyisocyanate; and (C) a silicone-based polymer formed on the polyurethane coating (a). And / or a top coat (b) containing a hydrolyzable silyl ester group-containing acrylic copolymer as a resin component. 6. The polyurethane coating (a) is a coating formed by spraying and curing a polyurethane coating containing a polyol and / or polythiol and a polyisocyanate in the presence of an amine vapor. The antifouling structure according to claim 5.