WO2002059221A2

WO2002059221A2 - Antifouling agent comprising a n-phenyl-n'-2,6-difluorobenzoyl urea derivative

Info

Publication number: WO2002059221A2
Application number: PCT/JP2002/000188
Authority: WO
Inventors: Kenji Mikami
Original assignee: Sds Biotech K.K.
Priority date: 2001-01-26
Filing date: 2002-01-15
Publication date: 2002-08-01
Also published as: JP2002220310A; WO2002059221A3; AU2002219616A1

Abstract

An antifouling agent comprising a urea compound of specified formula (1) wherein R1 represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group; R2 represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group; R3 represents a 1,1,2-trifluoro-2-trifluoromethoxyethoxy group; and R4 represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group. The urea compound is preferably N-{{{3-chloro-4-{1,1,2-trifluoro-2-trifluoromethoxy)ethoxy}phenyl}amino}carbonyl}-2,6-difluorobenzamide. The antifouling agent may further contain at least one member selected from the group consisting of a boron based effective component, a copper based effective component, a germicide and a herbicide.

Description

DESCRIPTION ANTIFOULING AGENT

FIELD OF THE INVENTION The present invention relates to an antifouling agent . More particularly, the present invention is concerned with a less pollutive antifouling agent which is capable of preventing the attachment of aquatic fouling organisms to the surface of an object brought into contact with sea water or fresh water and which can sustain an effect of such attachment prevention for a prolonged period of time.

BACKGROUND OF THE INVENTION

Shellfishes and seaweeds, such as barnacles, oysters, blue mussels, hydras, serpulas, ascidians, polyzoans, sea lettuces, green lavers and Ectocarpus , attach to and thickly grow on portions constantly brought into contact with sea water or brackish water.

The attachment of these organisms to shipbottoms causes an increase of flow resistance, thereby inviting a fuel loss . The attachment of these organisms to inlet channels and cooling equipments for cooling water used in condensers in a nuclear power plant or a thermal power plant or for cooling water used in heat exchangers in the petrochemical industry causes a drop of thermal conductivity, thereby inviting huge economic losses, for example, lowering of the capacity of facility equipment.

Various antifouling agents have been employed for preventing the attachment and thick growth of such harmful organisms of fresh water and sea water . For example, copper sulfate, cuprous oxide or an organotin compound is known as being an active component of such antifouling agents. This active component is contained in a paint in an amount of 10 to 50% by weight, and applied to, for example, a ship bottom. The active component is continually leached into water. Because of this leaching, attachment of harmful organisms can be prevented.

Conventionally, different types of active components are used in combination in an aquatic antifouling agent, such as an antifouling agent for fishing net or an antifouling paint for ship bottom. This can enhance the antifouling effect over a wider variety of sea living fouling organisms . However, there is a danger of environmental pollution in rivers and sea water by the above-mentioned heavy metals or hazardous elements. Further, because sparingly decomposable compounds and highly accumulative compounds are used, there is a danger of detriment to human health through the medium of fishes and shellfishes. Therefore, with respect to most often employed organotin compounds, the use thereof is under regulations. For example, in the United States, the use of organotin ship paints to ships of 65 feet or less is prohibited under the "Organotin antifouling paint regulating law" (1987). In Great Britain, the use of tributyltin containing antifouling agents on ships of 25 m or less and in oceanic fishing is prohibited under the "Rule on food & environment protection" (1987) .

In Japan, under the "Law pertaining to the examination and regulation on production of chemical substance" (1990) , tributyltin oxide is designated as the first-class specified chemical substance and triphenyltin and tributyltin compounds are designated as the second-class specified compounds , and theusethereof on fishingnetsis prohibited. Further, the "Action for restriction on the use of tributyltin type ship bottom paint" ( 1990 notification from the Ministry of Transport) is in effect.

Copper compounds are widely used in antifouling paints for inlet channels and ship bottoms. However, they are of a heavy metal like tin compounds, so that future environmental pollution is feared, urging us to reduce the usage thereof. Further, copper compounds have poor solubility in organic solvents, so that it is difficult to formulate them into a pharmaceutical preparation practicable and easily handleable as an antifouling agent for fishing net. On the other hand, less pollutive aquatic antifouling agents which do not contain heavy metals have been developed .

For example, Japanese Patent Publication No. 51 (1976) -10849 discloses an antifouling paint comprising, as an active ingredient, a benzothiazole compound, a benzoxazole compoundor a benzimidazole compound. Japanese Patent Laid-open Publication No. 60 (1985) -38306 discloses an antifouling agent for fishing net comprising, as active ingredients, a tetraalkylthiuram disulfide and/or a dialkyl polysulfide and a specified less poisonous organic compound. Japanese Patent Laid-open Publication No. 63 (1988) -284275 discloses an antifouling paint composition comprising, as active ingredients, at least two compounds selected from the group consisting of a benzothiazole compound, a tetraalkylthiuram disulfide compound and an N-haloalkylthio compound. Japanese Patent Publication No . 64 ( 1989) -11606 discloses an antifouling solution for fishing net comprising tetrachloroisophthalonitrile, a tetraalkylthiuram disulfide compound, an organic solvent dissolving these, such as xylene or solvent naphtha, and a benzene ring compound having methyl or ethyl, such as pseudocumene or mesitylene. Japanese Patent Publication No. 61 (1986) -50984 discloses an antifouling agent for oceanic construct comprising, as an active ingredient, a 3-isothiazolone compound. Furthermore, Published Japanese Translation of PCT Patent Applications in foreign language, No.9 ( 1997 ) -507084 discloses an antifouling composition comprising an insecticide, and also an antifouling composition further containing an algae killing agent, a herbicide, a germicide/fungicide, a molluscicide, etc. As the insecticide, there are mentioned, for example, specified benzoylureas such as trifl umuron , chlorfl ua ∑uron _r difluben∑uron , fl ufenoxuron , flucycloxuron _f hexaflumuron , penfl uron and tefl ubenzuron .

These organic antifouling agents, although having relatively high solubility in organic solvents and being easily formulated into a pharmaceutical preparation, are unexceptionally less effective in the prevention of attachment of fouling organisms. Thus, there is a demand for the development of a practical antifouling agent which can exert a wide range of attachment preventive effect (antifouling effect) against a great variety of fouling organisms . In these circumstances, the inventor hasmade extensive and intensive studies with a view to developing a compound which is highly safe and can exert an excellent antifouling effect. As a result, it has been found that specific urea compounds not disclosed in the above Published Japanese Translation of PCT Patent Applications in foreign language, No. 9 (1997) -507084 can exert a high antifouling effect against aquatic fouling organisms, are less pollutive and highly safe and exhibit excellent formulation performance. The present invention has been accomplished on the basis of this finding.

OBJECT OF THE INVENTION

The present invention has been made with the aim of solving the above problems of the prior art . It is an object of the present invention to provide an antifouling agent which is excellently capable of preventing the attachment and breeding of aquatic organisms, which can sustain an antifouling effect for a prolonged period of time, being less pollutive and highly safe, and which can be easily formulated into pharmaceutical preparations, is practical and ensures easy handling.

SUMMARY OF THE INVENTION

The antifouling agent of the present invention comprises a urea compound of the general formula:

wherein R-¹- represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group; R^ώ represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group; R^J represents a

1, 1, 2-trifluoro-2-trifluoromethoxyethoxy group; and R^ represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group.

It is preferred that the urea compound be N- [ [ [3-chloro-4- [1, 1, 2-trifluoro-2- (trifluoromethoxy) et hoxy] phenyl] amino] carbonyl] -2, 6-difluorobenzamide .

The antifouling agent preferably further comprises a boron compound.

The antifouling agent preferably further comprises a copper compound.

The antifouling agent preferably further comprises a germicide and/or a herbicide. DETAILED DESCRIPTION OF THE INVENTION

The antifouling agent of the present invention will be described in detail below.

wherein R-¹ represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group; R^~ represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group; R³ represents a

Urea compound

The urea compound for use in the present invention is a 2, 6-difluorobenzamide as represented by the general formula (1) wherein R^ is a

1, 1, 2-trifluoro-2-trifluoromethoxyethoxy group. The 2 , 6-difluorobenzamide can be, for example, N- [ [ [3-chloro-4- [1,1, 2-trifluoro-2- ( trifluoromethoxy) et hoxy] phenyl] amino] carbonyl] -2, 6-difluorobenzamide or N- [ [ [3, 5-dichloro-4- [1,1, 2-trifluoro-2- (trifluoromethox y) ethoxy] phenyl] amino] carbonyl] -2, 6-difluorobenzamide . Of these, N- [ [ [3-chloro-4- [1,1, 2-trifluoro-2- (trifluoromethoxy) et hoxy] phenyl] amino] carbonyl] -2 , 6-difluorobenzamide is preferred. This urea compound is known by the name of noval uron . and used as an insecticide in the fields of agriculture, forestry, public welfare and veterinary science . Reference can be made to The Pesticide Manual issued by British Crop Protection Council. The urea compound of the above structure exerts an insecticidal effect, a chitin synthesis inhibiting effect and a growth inhibiting effect; exerts an excellent antifouling effect against aquatic fouling organisms; and is less pollutive and highly safe, and exhibits excellent formulation performance.

This urea compound can be produced by known processes . For example, the urea compound such as N- [ [ [3-chloro-4- [1,1, 2-trifluoro-2- (trifluoromethoxy ) et hoxy] phenyl] amino] carbonyl] -2, 6-difluorobenzamide can be obtained by reacting a benzoyl isocyanate such as 2, 6-difluorobenzoyl isocyanate with an aromatic amine such as

3-chloro-4- [1,1, 2-trifluoro-2- (trifluoromethoxy) ethoxy] aniline in an inert solvent at a temperature between 0°C and the boiling point of reaction mixture according to the process described in Japanese Patent Laid-open Publication No. 63 ( 1988 ) -165356 and Japanese Patent Laid-open Publication No. 61 (1986) -280465. Antifouling agent The antifouling agent comprising the above urea compound according to the present invention can prevent the attachment of aquatic organisms to the surface of objects brought into contact with sea water or fresh water, for example, a marine transportation or structure such as a ship, a bridge or a rig, a sea water inlet pipe for use in a nuclear power plant or a thermal power plant, a pipe for feeding cooling water in a heat exchanger for use in the petrochemical industry, a stationary net, a fishing net for aqua culture, a rope, etc. Examples of the aquatic organisms include bacteria, diatom, barnacles, shellfishes such as oysters and blue mussels, hydras, serpulas, ascidians, polyzoans, seaweeds such as sea lettuce, green laver and Ectocarpus, andmollusc.

The antifouling agent of the present invention can be formulated into an appropriate form, such as a paint, a solution, pellets, flakes or a sheet, in conformity with the intended use and applied object, and can be applied to a wide variety of objects for which the prevention of attachment of aquatic organisms is needed. For example, the antifouling agent can be applied in the form of a paint in the use on a ship bottom, an underwater structure, a water channel or the like. The antifouling agent can be applied in the form of a solution or a paint of low viscosity in the use on a fishing net, a rope or the like. The antifouling agent can be applied by disposing it in the form of pellets at appropriate place in the use on cooling piping and other facilities where coating is difficult .

The content of the above urea compound in the antifouling agent of the present invention can be selected within the range of 0.1 to 100% by weight. The content of urea compound depending on the form of the antifouling agent can be, for example, as follows. In the form of a paint, the urea compound content can preferably be in the range of 1 to 50% by weight. In the form of a solution, the urea compound content can preferably be in the range of 0.1 to 30% by weight. In the form of pellets, the urea compound content can preferably be in the range of30tol00%by weight. However, the urea compound content can fall outside these ranges without any detriment. Other active component

With respect to the antifouling agent of the present invention, although a satisfactory antifouling effect can be exerted as long as the urea compound represented by the general formula (1) is contained, the urea compound can be optionally used in combination with other active components conventionally used in antifouling agents against aquatic attached organisms. Examples of such other active components include copper, copper compounds, boron, boron compounds, germicides and herbicides. These active components can be used, either individually or in mixture of a plurality thereof, in combination with the urea compound .

The copper or copper compound can be, for example, any of powder of a copper metal, such as copper powder or powder of copper/nickel alloy, and copper compounds, such as copper (I) oxide, cuprous thiocyanate, basic copper carbonate, copper pyrophosphate, copper naphthenate, copper abietate, copper oxyquinoline, copper sulfate, cuprous oxide, cupric oxide, copper nitrate, cuprous chloride and cupric chloride . These may be used individually or in combination. Of these, copper compounds are preferred. Cuprous oxide is most especially preferred.

The boron or boron compound can be, for example, any of boron per se, and boron compounds, such as borax, zinc borate, ammonium borate, sodium perborate, chromium boride, zirconium boride, tungsten boride, tantalum boride, titanium boride, niobium boride, molybdenum boride, lanthanum boride, aluminum borate, triethyl borate, trimethyl borate, manganese borate, ammonium borofluoride, potassium borofluoride and sodium borofluoride . These may be used individually or in combination. Of these, boric acid compounds and other boron compounds are preferred. Zinc borate is most especially preferred. The germicide can be, for example, any of: thiuram compounds such as tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetra-n-propylthiuram disulfide, tetraisopropylthiuram disulfide, tetra-n-butylthiuram disulfide, tetraisobutylthiuram disulfide,

N, N' -ethylenebisthiocarbamoyl sulfide,

N, N ' -propylenebisthiocarbamoyl sulfide and

N, N ' -butylenebisthiocarbamoyl sulfide; dithiocarbamate compounds such as zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, zinc ethylphenyldithiocarbamate, zinc ethylenebisdithiocarbamate, zinc propylenebisdithiocarbamate, zinc bis (dimethyldithiocarbamoyl) ethylenebisdithiocarbamate, manganese ethylenebisdithiocarbamate, nickel dimethyldithiocarbamate, nickel diethyldithiocarbamate, nickel dibutyldithiocarbamate, copper dimethyldithiocarbamate, copper diethyldithiocarbamate, copper dibutyldithiocarbamate, iron dimethyldithiocarbamate, iron diethyldithiocarbamate and iron dibutyldithiocarbamate; benzimidazole compounds such as

2-(4-thiazolyl) benzimida ole, methyl-1- (ω-cyanopentylcarbamoyl ) -2-benzimidazole,

2-mercaptobenzimidazole zinc and

2-thiocyanomethylthiobenzimidazole; benzothiazole compounds such as

2-mercaptobenzothiazole, 2- (thiocyanomethylthio) benzothiazole,

2- (thiocyanomethylsulfonyl) benzothiazole,

2-thiocyanoethylthio-4-chlorobenzothiazole,

2-thiocyanopropylthio-5' , 7-dichlorobenzothiazole and

2-thiocyanomethylthio-4, 5,6, 7-tetrachlorobenzothiazole; nitrile compounds such as tetrachloroisophthalonitrile and

5-chloro-2, 4-difluoro-6-methoxyisophthalonitrile; isothiazoline compounds such as

4, 5-dichloro-2-n-octyl-4-isothiazolin-3-one, 2-n-octyl-4-isothiazolin-3-one, 1, 2-benzoisothiazolin-3-one and

4, 5-dichloro-2-n-octyl-3-isothia olone; triazole compounds such as

1- [2- (2, 4-dichlorophenyl) -4-propyl-l, 3-dioxolanyl-2-met hyl]-lH-l,2,4-triazole and

4, 4-dimethyl-2- (1,2, 4-triazol-l-yl ) -1- (4-trifluoro ethy

1-2-chlorophneyl) -l-penten-2-ol; pyridine compounds such as

2, 3, 5, 6-tetrachloro-4- (methylsulfonyl) pyridine, 2,3,6-trichloro-4- (propylsulfonyl) pyridine,

2, 6-dichloro-3, 5-dicyano-4-phenylpyridine and triphenylboron pyridine ; triazine compounds such as

2, 4-dichloro-6- (α-chloroanilino) -s-triazine, 2-chloro- -methylamino-6-isopropylamino-s-triazine,

2-chloro-4, 6-bis (ethylamino) -s-triazine,

2-chloro-4, 6-bis (isopropylamino) -s-triazine,

2-methylthio-4, 6-bis (ethylamino) -s-triazine, -methylthio-4-ethylamino-6-isopropylamino-s-tria ine and

2-methylthio-4-t-butylamino-6-cyclopropylamino-s-triazi ne; urea compounds such as

3- (3, 4-dichlorophenyl) -1, 1-dimethylurea, 3- (3, 4-dichlorophenyl) -1-methoxy-l-methylurea, 1- (α, α' -dimethylben∑yl) -3-methyl-3-phenylurea and

1- (2-methylcyclophenyl) -3-phenylurea; quinone compounds such as

2-amino-3-chloro-l, -naphthoquinone and 2, 3-dicyano-dithianthraquinone; and

N-haloalkylthio compounds such as

N-trichloromethylthiotetrahydrophthalimide,

N-l, 1, 2, 2-tetrachloroethylthiotetrahydrophthalimide,

N-trichloromethylthiophthalimide, N-fluorodichloromethylthiophthalimide,

N, -dimethyl- ' -phenyl- ' - ( fluorodichloromethylthio) sul furylamide, trichloromethylthiomethanesulfon-p-chloroanilide,

N- (1, 1, 2 , 2~tetrachloro-2-fluoroethylthio) methanesulfona nilide,

N-fluorodichloromethylthio-N-3-chlorophenyl-N ' -dimethyl urea,

N-fluorodichloromethylthio-N-3, 4-dichlorophenyl- ' -dime thylurea and N-fluorodichloromethylthio-N-trissulfonyl-N-methylamine

These may be used individually or in combination. Of these, thiuram compounds, benzothiazole compounds, nitrile compounds and isothiazoline compounds are preferably used. For example, thiuram compounds such as tetramethylthiuram disulfide and tetraethylthiuram disulfide, benzothiazole compounds such as

2- (thiocyanomethylthio) benzothiazole, nitrile compounds such as tetrachloroisophthalonitrile, and isothiazoline compounds such as 4 , 5-dichloro-2-n-octyl-3-isothiazolone are still preferably used. Tetramethylthiuram disulfide, tetraethylthiuram disulfide and tetrachloroisophthalonitrile are especially preferably used. The herbicide can be, for example, any of: maleimide compounds such as

N- (2-chlorophenyl)maleimide,

N- (3, 5-dichlorophenyl) maleimide,

N- (2, 4, 6-trichlorophenyl)maleimide, N-4-tolylmaleimide and N-2 , 4-xylylmaleimide; thiadiazine compounds such as

3, 5-dimethyl-tetrahydro-l, 3,5,2 (H) -thiadiazin-2-one,

3,3' -ethylenebistetrahydro-4, 6-dimethyl-2H-l , 3, 5-thiadi azin-2-one, 3, 5-dimethyl-thiotetrahydro-l, 3, 5-thiadiazine and

3, 5-dibenzyl-tetrahydro-l, 3, 5-thiadiazin-2-one; thiocyan compounds such as methyl thiocyanide, chloro ethyl thiocyanide, ethyl thiocyanide, methylene bisthiocyanate, chloromethylene bisthiocyanate, ethylene bisthiocyanate, chloroethylene bisthiocyanate, isobornyl thiocyanate, methylthio isothiocyanate, allyl isothiocyanate, phenyl isothiocyanate and benzyl isothiocyanate; alkylphenol compounds such as caprylphenol and nonylphenol; alkylphenyl phosphite compounds such as tris (octylphenyl) phosphite, tris (nonylphenyl) phosphite, tris (dinonylphenyl) phosphite and tris (monσ-/dinonylphenyl) phosphite; and alkylphenyl phosphate compounds such as tris (octylphenyl) phosphate, tris (nonylphenyl ) phosphate, tris (dinonylphenyl ) phosphate and tris (mono-/dinonylphenyl ) phosphate.

These may be used individually or in combination. Of these, maleimide compounds are preferably used. N- ( 2-chlorophenyl) maleimide is especiallypreferably used. The content of simultaneously usable other components with antifouling activity (i.e. antifouling components with biological activity) , such as the above copper, copper compound, boron, boron compound, germicide and herbicide, in the antifouling agent can be selected in consideration of the intended fouling organisms, portions where attachment must be prevented, etc.

Moreover, a leaching regulating agent, such as vaseline, silicon, polybutene, chlorinated paraffin or a polysulfide compound, can be used in combination with the above urea compound and the above other active components (antifouling components with biological activity) . Formulation Depending on dosage form (form of antifouling agent) , the antifouling agent of the present invention can be appropriately loaded with materials incorporated in conventional antifouling agents against aquatic attached organisms, such as a coating film forming resin, a pigment, a plasticizer, a water repellency imparting agent, a surfactant, an antisetting agent, a thickener, an organic solvent and water.

The coating film forming resin can be, for example, any of an acrylic resin, an alkyd resin, a silicon resin, a polybutene resin, a vinyl resin, a styrene/butadiene resin, a cumarone resin, a rosin resin, an epoxy resin, a biodegradable ester resin, a polyurethane resin, apolyester resin, a polyethylene resin, a polyethylene oxide resin, a phenolic resin, a polyether resin, a polypropylene resin, a vinyl acetate resin and an aqueous emulsion.

The pigment can be, for example, any of color pigments, such as red iron oxide, carbon black, titanium dioxide and cyanineblue, and extender pigments, such as talc, zinc oxide and barium sulfate. The plasticizer can be, for example, any of chlorinated paraffin, tricresyl phosphate and dioctyl phthalate.

The water repellency imparting agent canbe, for example, any of liquid paraffin and modified silicone oil. With respect to the surfactant, antisetting agent, thickener and organic solvent, there is none whose use is particularly limited.

For example, toluene, xylene, solvent naphtha, pseudocumene, acetone, methyl ethyl ketone, dioxane, alkyl cellosolves, chloroformand the like canbe used individually or in combination as the organic solvent, depending on the employed active components, resin components, etc.

The method of formulating the antifouling agent of the present invention can be appropriately selected depending on dosage form. For example, in the formulation into a paint , first, the urea compound represented by the general formula (1) is optionally mixed with other active components (antifouling components with biological activity) , further with materials not altered by dispersion by means of a disperser among various materials as required for paint formulation, by the use of an agitator such as a dissolver. Thereafter, the mixture is dispersed by means of a disperser such as a sand mill, a three-roll mill or a paint shaker, and the remainder of materials is added thereto and mixed by the use of an agitator. In the formulation into pellets, the urea compound represented by the general formula (1) is optionally mixed with other active components, a surfactant, etc., and the mixture is molded by, for example, dissolution, cooling or compression.

EFFECT OF THE INVENTION

The antifouling agent comprising the urea compound of the general formula (1) as an active component according to the present invention is highly safe and has excellent capability of preventing organism attachment (i.e. antifouling capability) to prevent the attachment and breeding of aquatic organisms . This antifouling capability continues for a prolonged period of time. Thus, the antifouling agent is available for practical use.

Further, the antifouling agent of the present invention can be applied in appropriate form, for example, in the form of a paint, a solution, pellets, flakes or a sheet, depending on the intended use and object item. Hence, the antifouling agent can be applied to a wide variety of objects for which the attachment of aquatic organisms must be prevented. The formulation of the antifouling agent can be easily accomplished.

With respect to the antifouling agent of the present invention, the use of the above urea compound in combination with other active components such as a copper component, a boron component, a germicide and a herbicide enables to exert more effective antifouling capability against a large variety of fouling organisms.

Still further, the presence of the above urea compound of the present invention in conventional antifouling agents comprising other active components of poor antifouling effect enables to enhance the antifouling effect of the conventional antifouling agents.

EXAMPLES

The present invention will further be illustrated below with reference to the following Examples, which in no way limit the scope of the invention. Recipe Examples 1 to 9

Recipe Examples 1 to 9 wherein the antifouling agent of the present invention was used in the form of an antifouling paint were as follows.

In the following recipe examples, N- [ [ [3-chloro-4- [1,1, -trifluoro-2- (trifluoromethoxy) et hoxy] phenyl] amino] carbonyl] -2, 6-difluorobenzamide (hereinafter referred to as "compound 1") was used as the urea compound of the present invention.

Recipe Example 1 Component wt . %

compound 1 8

VYHH (vinyl-based synthetic resin) 7 rosin resin 7 tricresyl phosphate 3 talc 20 barium sulfate 15 red iron oxide 10 xylene 20 methyl isobutyl ketone 10

total 100

Recipe Example 2

Component wt . %

compound 1 5 chlorinated rubber resin 13 zinc oxide 20 talc 20 plasticizer 2 red iron oxide 10 xylene 30 total 100

Recipe Example 3

Component wt . %

compound 1 15 tetraethylthiuram disulfide 15 talc 15 barium sulfate 3 red iron oxide 15 rosin resin 11 chlorinated rubber resin 5 tricresyl phosphate 3 xylene 18

total 100

Recipe Example 4

Component wt.%

compound 1 20 tetraethylthiuram disulfide 10 cuprous oxide 15 talc 10 barium sulfate 5 red iron oxide 5 rosin resm 11 chlorinated rubber resin 5 tricresyl phosphate 3 xylene 16

total 100

Recipe Example 5 Component wt ,

compound 1 20 cuprous oxide 30 talc 5 barium sulfate 5 red iron oxide 10 rosin resin 11 chlorinated rubber resin 5 tricresyl phosphate 3 xylene 11

total 100

Recipe Example 6 Component wt . %

compound 1 15

2- (thiocyanomethylthio) benzothiazole 15 talc 3 barium sulfate 5 red iron oxide 15 rosin resin 11 chlorinated rubber resin 5 tricresyl phosphate 3 xylene 28

total 100

Recipe Example 7

Component wt.%

compound 1 15 tetrachloroisophthalonitrile 15 talc 3 barium sulfate 5 red iron oxide 15 rosin resin 11 chlorinated rubber resin 5 tricresyl phosphate 3 xylene

total 100

Recipe Example 8

Component wt.%

compound 1 15

2- (thiocyanomethylthio) benzothiazole 15 4 , 5-dichloro-2-n-octyl-3-isothiazolone 10 cuprous oxide 10 talc 10 barium sulfate 5 red iron oxide 5 rosin resin 11 chlorinated rubber resin 5 tricresyl phosphate 3 xylene 11

total 100

Recipe Example 9

Component wt.%

compound 1 15 tetraethylthiuram disulfide 15

4, 5-dichloro-2-n-octyl-3-isothiazolone 10 talc 3 barium sulfate 5 red iron oxide 13 rosin resin 11 chlorinated rubber resin 5 tricresyl phosphate 3 xylene 20

total 100

Recipe Examples 10 to 17

Recipe Examples 10 to 17 wherein the antifouling agent ofthe present invention wasusedin the form of an antifouling agent solution were as follows.

Recipe Example 10

Component wt.%

compound 1 15 acrylic resin 50 xylene 35

total 100 Recipe Example 11

Component wt . %

compound 1 10 acrylic resin 40 di-tert-nonyl pentasulfide 5 liquid paraffin 5 xylene 40

total 100

Recipe Example 12

Component wt . %

compound 1 10 acrylic resin 50 rosin resin 3 xylene 37

total 100

Recipe Example 13

Component wt.%

compound 1 10 tetraethylthiuram disulfide 5 acrylic resin 48 di-tert-nonyl pentasulfide 5 xylene 32

total 100

Recipe Example 14

Component wt.%

compound 1 5 tetraethylthiuram disulfide 10 rosin resin 40 di-tert-nonyl pentasulfide 5 xylene 40

total 100

Recipe Example 15 Component wt.%

compound 1 10

2- (thiocyanomethylthio) benzothiazole 5 acrylic resin 40 di-tert-nonyl pentasulfide 5 xylene

total 100

Recipe Example 16

Component wt.%

compound 1 5 tetrachloroisophthalonitrile 5 acrylic resin 40 di-tert-nonyl pentasulfide 5 pseudocumene 45

total 100

Recipe Example 17

Component t ,

compound 1 5 tetraethylthiuram disulfide 5

4, 5-dichloro-2-n-octyl-3-isothiazolone 5 acrylic resin 40 di-tert-nonyl pentasulfide 5 xylene 40 total 100

Comparative Recipe Examples 1 to 11

Comparative Recipe Examples 1 to 11 wherein a copper compound as an active component of known antifouling agents and insecticides, i.e., diflubenzuron , tefl ubenzuron , l ufenuron, triflumuron , pyriproxyfen, methoprene , chlorfluazuron , cyromazine , fenoxycarb and flufenoxuron, as active components of the antifouling agent described in the above Published Japanese Translation of PCT Patent Applications in foreign language, No. 9 (1997 ) -507084 , were used in the form of an antifouling paint were as follows.

Comparative Recipe Example 1 Component wt.%

cuprous oxide 40 talc 5 red iron oxide 8 rosin resin 10 chlorinated rubber resin 6 tricresyl phosphate 3 xylene 28

total 100 Comparative Recipe Example 2

Component wt . %

di fl ubenzuron 8

total 100

Comparative Recipe Example 3

Component wt.%

teflubenzu on 8

total 100

Comparative Recipe Example 4

Component wt.%

l ufenuron 8

total 100

Comparative Recipe Example 5

Component wt.%

trifl umuron 8 VYHH (vinyl-based synthetic resin) 7 rosin resin 7 tricresyl phosphate 3 talc 20 barium sulfate 15 red iron oxide • 10 xylene 20 methyl isobutyl ketone 10

total 100

Comparative Recipe Example 6

Component wt . ^!

pyriproxyfen 8

total 100 Comparative Recipe Example 7

Component wt.%

me thoprene 8

total 100

Comparative Recipe Example 8

Component wt.%

chlorfl ua zuron 8

total _ 100

Comparative Recipe Example 9

Component wt.%

cyroma zine 8

total 100

Comparative Recipe Example 10

Component wt.%

fenoxycarb 8 VYHH (vinyl-based synthetic resin) 7 rosin resin 7 tricresyl phosphate 3 talc 20 barium sulfate 15 red iron oxide 10 xylene 20 methyl isobutyl ketone 10

total 100

Comparative Recipe Example 11

Component wt . ^<

fl ufenoxuron 8

total 100 Comparative Recipe Examples 12 to 22 Comparative Recipe Examples 12 to 22 wherein tetraethylthiuram disulfide as an active component of known antifouling agents and the above insecticides as active components of the antifouling agent described in Published Japanese Translation of PCT Patent Applications in foreign language, No. 9 ( 1997 ) -507084 , were used in the form of an antifouling agent solution were as follows.

Comparative Recipe Example 12 Component wt.%

tetraethylthiuram disulfide 15 acrylic resin (50% xylene solution) 50 xylene 35

total 100

Comparative Recipe Example 13

Component wt . %

difl ubenzuron 5 tetraethylthiuram disulfide 5 4 , 5-dichloro-2 -n-octyl -3 -isothia zolone 5 acrylic resin 40 di-tert-nonyl pentasulfide 5 xylene 40

total 100

Comparative Recipe Example 14

Component wt.%

tefl ubenzuron 5 tetraethylthiuram disulfide 5

4, 5-dichloro-2-n-octyl-3-isothiazolone 5 acrylic resin '40 di-tert-nonyl pentasulfide 5 xylene 40

total 100

Comparative Recipe Example 15 Component wt.%

l ufen uron 5 tetraethylthiuram disulfide 5

4, 5-dichloro-2-n-octyl-3-isothiazolone 5 acrylic resin 40 di-tert-nonyl pentasulfide 5 xylene 40

total 100

Comparative Recipe Example 16

Component wt.%

trifl umuron 5 tetraethylthiuram disulfide 5

total 100

Comparative Recipe Example 17

Component wt.%

pyriproxyfen 5 tetraethylthiuram disulfide ^• 5

total 100

Comparative Recipe Example 18

Component wt.%

methoprene 5 tetraethylthiuram disulfide 5 4, 5-dichloro-2-n-octyl-3-isothiazolone 5 acrylic resin 40 di-tert-nonyl pentasulfide 5 xylene 40

total 100

Comparative Recipe Example 19

Component wt.%

chl orfl ua ∑uron 5 tetraethylthiuram disulfide 5

total 100

Comparative Recipe Example 20

Component wt.%

cyroma zine 5 tetraethylthiuram disulfide 5 4, 5-dichloro-2-n-octyl-3-isothiazolone 5 acrylic resin 40 di-tert-nonyl pentasulfide 5 xylene 40

total 100

Comparative Recipe Example 21

Component wt . %

fenoxyca rb 5 tetraethylthiuram disulfide 5

total 100

Comparative Recipe Example 22

Component wt . %

fl ufenoxuron 5 tetraethylthiuram disulfide 5 4, 5-dichloro-2-n-octyl-3-isothiazolone 5 acrylic resin 40 di-tert-nonyl pentasulfide 5 xylene 40

total 100

Example 1

The antifouling paint of Recipe Example 1 was used as the antifouling paint for ship bottom according to the present invention.

A test steel plate pre-coated with a rust preventive paint was uniformly coated with the antifouling paint of

Recipe Example 1 by the use of a brush twice, and air dried.

The thus obtained test steel plate coated with the antifouling paint of Recipe Example 1 was immersed in the sea water close to 8, EbisuTown, Kanagawa District , Yokohama City, Kanagawa Prefecture at a depth of about 1.5 m for one year from August, 1999. Every two months after the start of immersion, the level of attachment of fouling organisms onto the test steel plate was inspected.

The results are listed in Table 1. The numerals appearing in the table indicate the percentage (%) of the area where the attachment of fouling organisms was recognized. The attachment of fouling organisms onto a test steel plate coated with a rust preventive paint but not coated with any antifouling paint was also investigated in the same manner. The results are given in Table 1 as noncoating example . Examples 2 to 9

The attachment of fouling organisms was investigated in the same manner as in Example 1 except that antifouling paints of Recipe Examples 2 to 9 were employed in place of the antifouling paint of Recipe Example 1. The results are listed in Table 1. Comparative Examples 1 to 11

The attachment of fouling organisms was investigated in the same manner as in Example 1 except that antifouling paints of Comparative Recipe Examples 1 to 11 were employed in place of the antifouling paint of Recipe Example 1. The results are listed in Table 1.

Table 1

It is apparent from Table 1 that the antifouling paints for ship bottom comprising as an active component the urea compound (compound 1) according to the present invention (Examples 1 to 9) , as compared with the conventional antifouling paint comprising cuprous oxide as an only active component (Comparative Example 1) and the antifouling paints comprising as an active component the insecticides described in Published Japanese Translation of PCT Patent Applications in foreign language, No. 9 ( 1997 ) -507084 (Comparative

Examples 2 to 11), are strikingly effective in preventing the attachment of fouling organisms, and that this effect is continuous. Therefore, it is apparent that the antifouling paints of the present invention are suitable for practical use.

Further, the antifouling effect of the antifouling paint for ship bottom comprising as active components the urea compound (compound 1) and cuprous oxide according to the present invention (Example 5) continues over a prolonged period of time as compared with that of the conventional antifouling paint comprising cuprous oxide (Comparative Example 1). Therefore, it is apparent that the presence of the urea compound of the present invention in conventional antifouling paints comprising an active component of poor antifouling effect (cuprous oxide) strikingly enhances the antifouling effect.

Still further, it is apparent that, in the antifouling paint for ship bottom according to the present invention, not only the sole use of the urea compound (compound 1)

(Examples 1 and 2) but also the use thereof in combination with at least one active component selected from among tetraethylthiuram disulfide, cuprous oxide,

2- (thiocyanomethylthio) benzothiazole, tetrachloroisophthalonitrile and , 5-dichloro-2-n-octyl-3-isothiazolone (Examples 3 to 9) realizes a high persistent antifouling effect.

The antifouling paint for ship bottom comprising as an active component the urea compound (compound 1) according to the present invention not only exerts a high antifouling effect but also ensures low toxicity and high safety. Thus, it enables to provide an antifouling paint of reduced environmental load. Example 10 The antifouling agent solution of Recipe Example 10 was used as an antifouling agent for fishing net according to the present invention.

Knotless fishing net of polyethylene (6 nodal points,

400 deniers/60 yarns) was dipped in the antifouling agent solution of Recipe Example 10, taken out and air dried, thereby obtaining a test fishing net coated with the antifouling agent of Recipe Example 10. The obtained test fishing net was immersed in the sea water close to 8, Ebisu Town, Kanagawa District , Yokohama City, Kanagawa Prefecture at a depth of about 0.5 m for four months from August, 1999.

Every one month after the start of immersion, the level of attachment of fouling organisms onto the test fishing net was inspected.

The results were evaluated on the criteria of Table 2, and listed in Table 3.

The attachment of fouling organisms onto a knotless fishing net of polyethylene to which no antifouling agent solution was applied was also investigated in the same manner . The results are given in Table 3 as noncoating example. Examples 11 to 17

The attachment of fouling organisms was investigated in the same manner as in Example 10 except that antifouling agent solutions of Recipe Examples 11 to 17 were employed in place of the antifouling agent solution of Recipe Example 10.

The results are listed in Table 3.

Comparative Examples 12 to 22

The attachment of fouling organisms was investigated in the same manner as in Example 10 except that antifouling agent solutions of Comparative Recipe Examples 12 to 22 were employed in place of the antifouling agent solution of Recipe Example 10.

The results are listed in Table 3.

Table 2

Table 3

It is apparent from Table 3 that the antifouling agents for fishing net comprising as an active component the urea compound (compound 1) according to the present invention (Examples 10 to 17), as compared with the conventional antifouling agent for fishing net comprising tetraethylthiuram disulfide as an only active component (Comparative Example 12) and the antifouling agents for fishing net comprising as an active component the insecticides described in Published Japanese Translation of PCT Patent Applications in foreign language, No. 9(1997) -507084 (Comparative Examples 13 to 22), are strikingly effective in preventing the attachment of fouling organisms, and that this effect is continuous. Therefore, it is apparent that the antifouling agents of the present invention are suitable for practical use.

Further, the antifouling effect of the antifouling agents for fishing net comprising as active components the urea compound (compound 1) and tetraethylthiuram disulfide according to the present invention (Example 13 and 14) continues over a prolonged period of time as compared with that of the conventional antifouling agent comprising tetraethylthiuram disulfide (Comparative Example 12).

Therefore, it is apparent that the presence of the specified urea compound of the present invention in conventional antifouling agents comprising an active component of poor antifouling effect (tetraethylthiuram disulfide) strikingly enhances the antifouling effect. Still further, it is apparent that, in the antifouling agent for fishing net according to the present invention, not only the sole use of the urea compound (compound 1) (Examples 10 to 12) but also the use thereof in combination with at least one active component selected from among 2- (thiocyanomethylthio) benzothiazole, tetrachloroisophthalonitrile, 4 , 5-dichloro-2-n-octyl-3-isothiazolone and tetraethylthiuram disulfide (Examples 13 to 17) realizes a high persistent antifouling effect.

The antifouling agent for fishing net comprising as an active component the urea compound (compound 1) according to the present invention not only exerts a high antifouling effect but also ensures low toxicity and high safety. Thus, it enables to provide a fishing net antifouling agent of reduced environmental load.

Claims

1. An antifouling agent comprising a urea compound of the general formula:

wherein R-¹ represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group; R*- represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group; R³ represents a 1, 1, 2-trifluoro-2-trifluoromethoxyethoxy group; and R^ represents a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, a methoxy group or a methylthio group. 2. The antifouling agent as claimed in claim 1, wherein the urea compound is

N-{ { { 3-chloro-4- {1,1,

2-trifluoro-2- (trifluoromethoxy) et hoxy }phenyl } amino } carbonyl } -2 , 6-difluorobenzamide .

3. The antifouling agent as claimed in claim 1 or 2, further comprising a boron compound.

4. The antifouling agent as claimed in any of claims 3, further comprising a copper compound.

5. The antifouling agent as claimed in any of claims , further comprising a germicide and/or a herbicide.