TW201305289A - Biocidal foul release coating systems - Google Patents

Abstract

Structure coated with a biocidal foul release coating system, the structure being obtained by a. providing a substrate, b. coating the substrate with a first coating layer, c. applying at least one subsequent coating layer on top of the first coating layer, the first coating layer containing a biocide, the subsequent coating layer(s) containing less biocide than the first coating layer and which is(are) free or substantially free of biocide, and wherein the first and the subsequent coating layer(s) form a biocidal foul release coating system showing a controlled leaching of the biocide.

Description

Biocidal dirt release coating system

The present invention relates to the use of a soil release coating to control the leaching of a biocide from a coating system comprising the soil release coating and the biocidal undercoat. The invention further relates to the coating system, its use for inhibiting fouling on a substrate, and substrates coated by the coating system.

Artificial marine structures such as boats and hulls, buoys, drilling platforms, dry dock equipment, oil rigs and pipelines immersed in water are prone to fouling by aquatic organisms such as green algae and brown algae, barnacles, mussels and the like. These structures are generally made of metal, but may also contain other structural materials such as concrete. This fouling is a nuisance on the hull as it increases the frictional resistance during movement through the water, resulting in reduced speed and increased fuel costs. It is a problem with static structures such as drill platform supports and oil rigs. First, because the resistance of the thick scale layer to waves and water flow can cause unpredictable and potentially dangerous stresses in the structure, and its secondary system is difficult to form due to fouling. Check for structural stresses such as stress cracking and corrosion. It is plagued by lines such as cooling water inlets and outlets because the effective cross-sectional area is reduced due to fouling, so that the flow rate is reduced.

Traditionally, fouling is inhibited by an antifouling coating containing a biocide that gradually leaches out of the coating. The most commercially successful method of inhibiting fouling involves the use of antifouling coatings containing substances that are toxic to aquatic life, such as triorganotin compounds. However, due to the damaging effects that some of these toxins may have if released into the aquatic environment under certain conditions, These coatings are becoming less and less popular.

Certain coatings, such as those disclosed in GB 1,307,001 and US 3,702,778, which have been known for many years, such as elastomers (e.g., polyoxyxides), are resistant to fouling by aquatic organisms. Such coatings are non-biocidal, generally hydrophobic, and are believed to exhibit surfaces that physically prevent settling and/or inability of the organism to adhere readily, and thus may be referred to as soil release coatings rather than antifouling coatings. Soil release properties can be characterized by barnacle adhesion measurements (eg, ASTM D 5618-94). The following barnacle sticking values have been recorded by this method: polyxanthene surface (0.05 MPa), polypropylene surface (0.85 MPa), polycarbonate surface (0.96 MPa), epoxy resin surface (1.52 MPa) and amine Carbamate surface (1.53 MPa) (JCLewthwaite, AFMolland and KW Thomas, "An Investigation into the variation of ship skin fictional resistance with fouling", Trans. RINA, Vol. 127, pp. 269-284, London (1984)). As an indication of whether the coating can be considered as a release of dirt: the soil release coating typically has an average barnacle adhesion value of less than 0.4 MPa.

Polyoxyxene rubbers and polyoxyxides generally have relatively low toxicity. One of the disadvantages of this soil release system when applied to a boat is that although the accumulation of fouling organisms is reduced, a relatively high container speed is required to remove all fouling material. Therefore, in some cases it has been shown that it is necessary to sail at a speed of at least 10 knots to satisfactorily remove scale from the hull treated with this paint. For this reason, polyoxyxene rubber has so far only achieved limited commercial results.

It has also been known for a long time that the adhesion of polyoxygenated soil release coatings to anticorrosive coatings is generally poor unless a suitable adhesive coating or chain coating is used. Make sure it sticks enough. These bonding coatings typically contain polyfluorene oxide. Examples of polyfluorene oxides containing a cohesive coating are described in EP 521983 and EP 1832630.

The combination of a suitable adhesive coating and a second coating is sometimes referred to as a "double" soil release system. To date, the compositions described in the prior art as bonding coatings in such dual systems are generally free of added biocides, and WO 2008/013825 expressly teaches that no biocides are used as part of their system.

GB 1409048 discloses a maritime polyurethane topcoat composition capable of absorbing 30 to 300% of its own weight of seawater and applied to a biocidal antifouling coating. The polyurethane topcoat of GB 1409048 is not a soil release coating within the scope of the invention (see: "Redefining antifouling coatings", Journal of Protective Coatings and Linings, September 1999, pages 26 to 35, It is revealed that the polyurethane has a very high barnacle adhesion strength compared to polyoxymethane. A subsequent soil release coating layer is not disclosed or suggested in GB 1409048.

EP 0 313 233 describes an antifouling maritime coating comprising a first layer of an antifouling and anticorrosive marine coating containing a toxic substance to marine life and a second layer of a porous organic polymeric film adhered to the first layer; The polymeric film is preferably polytetrafluoroethylene (EPTFE). The porous organic polymeric film is not a coating within the scope of the invention as it is not applied as a liquid mixture and subsequently dried or cured to form a dry continuous film. Further, polytetrafluoroethylene is not suitable as a material for the soil release surface (see: "Redefining antifouling coatings" above, which indicates the adhesion strength of the high barnacle). EP 0 313 The use of a subsequent soil release coating layer is neither disclosed nor suggested in 233.

No. 4,129,610 describes a water-soluble coating composition for the bottom of a ship comprising an ethylene-based copolymer and a water-soluble epoxy compound. The water soluble coating composition is applied to a primer layer having a toxic material. The water-soluble coating composition of US 4,129,610 is not considered to be a soil release coating within the scope of the present invention (see the "Redefining antifouling coatings" document above, which reports that the barnacle adhesion strength of the epoxy coating is extremely high). The use of a subsequent soil release coating layer has also not been disclosed and suggested.

FR 2636958 describes chlorinated adhesion primers for polyoxyxene elastomers. According to this disclosure, a triorganotin oxide or a halide biocide or copper oxide can be added to the primer. Tributyltin oxide or fluoride and copper oxide are the only suitable biocide additives for this system, and there are no examples or additional instructions for primers containing any biocide. This document does not mention at all the leaching of biocides and there is no teaching of a soil release system with a primer containing any biocide.

WO 95/32862 discloses a dual soil release system that can be used on a substrate to combat marine biofouling. The dual system consists of an adhesive layer and a release layer in which a 3-isothiazolone biocide is embedded in the adhesive layer or release layer. This document mainly teaches that 3-isothiazolone should be used as a biocide, and the rate at which the biocide is leached from the binder layer is inversely proportional to the square root of time, and there may be no other factors controlling the leaching except for the solubility of the biocide in water. rate. Thus, the leaching of biocide in such systems is only poorly controlled and is not eligible as a biocidal soil release coating system with controlled biocide leaching rates within the framework of the present invention. Found a class A substrate such as that disclosed in WO 95/32862, in which the leaching rate of the biocide from the adhesive layer is inversely proportional to the square root of the time, the substrate remains substantially free of fouling shortly after the substrate is immersed in seawater. It exhibits superior performance compared to substrates coated with a biocide-free soil release coating system. However, this superior performance is not maintained, the coated substrate is gradually covered by biofouling, and within 4 to 6 months, the system of WO 95/32862 exhibits coating with a biocide-free soil release coating system. The substrate is covered with similar serious fouling.

Surprisingly, it has been found that a structure coated with a biocidal soil release coating system exhibiting controlled leaching of a biocide can be made.

According to the present invention, the structure can be obtained by: a. providing a substrate, b. coating the substrate with a first coating layer, c. applying at least one subsequent coating layer on top of the first coating layer, wherein The first and the (or subsequent) coating layers form a biocidal soil release coating system, the first coating layer comprising a biocide, the (or subsequent) coating layer comprising less biocide than the first coating layer, and The (equal) subsequent coating layer is free or substantially free of biocide.

A biocidal soil release coating system as defined in the present application exhibits controlled leaching of the biocide.

By controlled leaching of the biocide, we mean the rate at which the biocide is released from the soil release coating system of the present invention after 5 days of application of the coating (R ₅ ) and the biocide after 30 days of application of the coating. The ratio of release rate (R ₃₀ ) R ₅ /R ₃₀ is less than or equal to ( ) 1.5, preferably 1.33, better 1.11.

The biocide-based soil release coating system of the present invention exhibits excellent anti-fouling properties in a short time and for a long period of time after immersing the substrate in seawater.

Within the framework of the present invention, the biocidal soil release coating system is a coating system having a surface that physically blocks sedimentation and/or which is not readily adhered by aquatic/marine organisms, and the biocide is released from the surface from the coating system.

In order to improve adhesion of the first coating layer to the substrate, a bonding coating or adhesion promoter layer may be present between the substrate and the first coating layer. In order to improve the corrosion resistance of the substrate, an anti-corrosive coating may also be applied to the substrate prior to application of the first coating layer. More generally, one or more layers of coating may be present on the substrate prior to applying the first coating layer comprising the biocide to the substrate.

To prepare a coating layer, a coating composition as a liquid mixture is applied to the surface (eg, to the substrate or another coating layer); subsequently, the coating composition is dried or cured to form a dry continuous coating film/layer on the surface. .

The inventors have appreciated that the rate at which the biocide can be leached from the biocidal soil release coating system can be controlled by applying one or more subsequent coating layers on top of the first coating layer, wherein the first coating layer contains a biocide. The subsequent coating layer contains less biocide than the first coating layer and is free or substantially free of biocide. The advantage is that it can adjust the biocide leaching rate, reduce the correlation with time and actually maintain a more linear relationship with time. Thus, a desired and more constant biocide leaching rate can be achieved. This is advantageous because it leads to prolonged performance life and more efficient use of biocidal And reduce environmental impact. In addition, biocide leaching can be controlled so as to enhance, inter alia, the ability of the scale release coating system to prevent fouling under low speed or static conditions.

In the context of the present invention, biocide leaching (sometimes referred to as biocide release) and biocide leaching rate (biocide release rate) should be clearly distinguished from soil release. The leaching rate is the rate at which the biocide is released into the surrounding water via the coating system and is typically expressed as the mass of biocide per unit area per unit time. Soil release is associated with the prevention of fouling and/or its ease of removal from the surface of the substrate by non-biocidal means. For example, soil release properties can be characterized by barnacle adhesion measurements, which can be performed using ASTM D 5618-94, a standard test method or related method for measuring the barley bond shear strength. Both are complementary mechanisms that control fouling but are independent of each other.

More specifically, the inventors have appreciated that the leaching rate can be controlled by varying the composition of the (and subsequent) coating layers. The first coating layer is like a reservoir containing the biocide ready to be supplied to release the biocide. The leaching rate of the biocide can be controlled by varying certain characteristics of the first and the subsequent coating layers. Such characteristics include, but are not limited to, pigment volume concentration, crosslink density, pigment size and shape, molecular weight of the polymer, presence or absence of an incompatible fluid, and crosslinking chemistry of the subsequent coating layer. And film thickness.

The biocide reservoir in combination with the control mechanism of the (and subsequent) coating layers allows the biocide leaching rate to be adjusted for the end use.

Within the framework of the present invention, the release rate (R ₃₀ ) of the biocide after 30 days of immersion in the coating system exhibiting controlled leaching of the biocide is at least 67 of the release rate (R ₅ ) after immersion in water for 5 days. % of the system. In other words, the coating system exhibiting controlled leaching of biocides is R ₅ /R ₃₀ 1.5 system.

In an embodiment of the invention, R ₅ /R ₃₀ 1.5. In another embodiment of the invention, R ₅ /R ₃₀ 1.33. In still another embodiment of the invention, R ₅ /R ₃₀ 1.11.

In WO 95/32862, the dual soil release system is described as having a leaching rate of biocide from the adhesive layer that is inversely proportional to the square root of time, and may have no other factors controlling the leaching rate other than the solubility of the biocide in water. . With regard to this system, the release rate of biocide is described as F(t)~36/t ^0.5 , where F is the leaching rate and t system in μg/cm ² /day (μg cm ^-2 day ^-1 ). Time in days. For this system, R ₅ /R ₃₀ =F(5)/F(30)=30 ^0.5 /5 ^0.5 =2.45. WO 95/32862 does not teach that a biocidal soil release coating system in which a substrate is first coated with a coating layer containing a biocide followed by a subsequent layer substantially free of biocide will result in a biocide from The dirt releases a more gradual and sustained release profile of the coating surface.

According to the invention, the subsequent coating layer applied to the top of the first coating layer contains less biocide than the first coating layer. Moreover, the (equal) subsequent coating layer is free or substantially free of biocide. Substantially free of biocide means that the subsequent coating layer contains less than 1.0 wt% (based on the total weight of the coating composition) of the biocide. Preferably, the (equal) subsequent coating layer contains less than 0.5% by weight of biocide, more preferably less than 0.1% by weight. For the avoidance of doubt, the weight percentage (wt%) is based on the weight percent of the total weight of the coating composition.

In an embodiment, the (equal) subsequent coating layer additionally comprises an incompatible fluid.

Incompatible fluids in the (and subsequent) coating layers help achieve improved soil release performance. Without wishing to be bound by theory, it is believed that the fluid will affect the delivery of the biocide.

In another embodiment, the biocide is partially or fully encapsulated or adsorbed or supported or bonded.

Encapsulation or absorption or support or combination of the biocide can provide a secondary mechanism for controlling the leaching of the biocide from the coating system to achieve a more gradual release and a longer lasting effect.

The present invention relates to (i) a biocidal soil release coating system, and (ii) a structure coated by the biocidal soil release coating system, the biocidal soil release coating system comprising: a. substrate, b. a coating layer, c. at least one subsequent coating layer on top of the first coating layer, the first coating layer containing a biocide, the (or) subsequent coating layer containing less biocides than the first coating layer And the (or subsequent) coating layer is free or substantially free of biocide. The biocide soil release coating system exhibits controlled leaching of the biocide.

One embodiment of the invention is a structure coated with a biocidal soil release coating system as defined above.

First coating layer containing biocide

The composition of the first coating layer is not particularly limited, but the composition of the first coating layer preferably contains a polymer. The polymer preferably forms an elastomer. More preferably, it is a polyorganosiloxane. Even more preferably, it is a polydimethyl siloxane. In addition, the polyorganosiloxane may also comprise two or more polyorganosiloxanes of different viscosities.

Preferably, the polyorganosiloxane has one or more, more preferably two or more reactive functional groups, such as a hydroxyl group, an alkoxy group, an ethyloxy group, a carboxyl group, a hydrodecyl group, an amine group, a ring. An oxy, vinyl or hydrazine functional group.

The polymer is preferably present in an amount of from 5 to 50% by weight based on the total weight of the coating composition. More preferably, it is present in an amount of from 8 to 20% by weight.

The polymer is preferably crosslinkable. The coating composition may require a crosslinking agent depending on the type of crosslinkable polymer. The necessity of the presence of the crosslinker will depend on the type and amount of functional groups present in the polymer. If the polymer comprises an alkoxy-methylidene group, a small amount of water is present and, as the case may be, the condensation catalyst is generally sufficient to achieve complete cure of the coating after application. For such compositions, atmospheric moisture is generally sufficient to induce curing, and generally does not require heating of the coating composition after application.

The crosslinking agent which may optionally be present may be a crosslinking agent comprising any one or more of a functionalized decane and/or an ethoxylated, alkoxy, decylamino, alkoxy and fluorenyl group. Examples of such crosslinkers are set forth in WO 99/33927, page 19, line 9 to page 21, line 17. Mixtures of different crosslinkers can also be used.

The crosslinking agent is preferably present in an amount of from 0.1% to 20% by weight based on the total weight of the coating composition.

The first coating layer comprises a biocide. By "comprising" / "containing", it is meant that the biocide is present in the body of the coating layer (meaning it is mixed in the coating composition prior to curing/drying).

The biocide of the present invention can be used in one or more of inorganic, organometallic, metal-organic or organic biocides of marine or freshwater organisms. Examples of inorganic biocides include copper salts such as copper oxide, copper thiocyanate, bronze, copper carbonate, copper chloride, copper-nickel alloys, and silver salts such as silver chloride or silver nitrate; organometallic and metal-organic killing organisms The agent comprises zinc pyrithione (zinc salt of 2-pyridine thiol-1-oxide), copper pyrithione, copper bis(N-cyclohexyl-diazonium dioxygen), ethyl bis-disulfide Zinc carbazide (ie zineb); zinc dimethyldithiocarbamate (ziram) and ethyl-bis(dithioamine) mismatched with zinc salt Manganese (mancozeb); and organic biocide comprising formaldehyde, dodecyl hydrazine monohydrochloride, thiabendazole, N-trihalomethylthioortho Benzoquinone imine, trihalomethylthiosulfate amine, N-aryl maleimide such as, for example, N-(2,4,6-trichlorophenyl)maleimide, 3- (3,4-dichlorophenyl)-1,1-dimethylurea (diuron), 2,3,5,6-tetrachloro-4-(methylsulfonyl)pyridine, 2 -Methylthio-4-butylamino-6-cyclopropylamino-s-triazine, 3-benzo[b]thiophene-yl-5,6-dihydro-1,4,2-oxathiazide 4 -oxide, 4,5-dichloro-2-( Octyl)-3(2H)-isothiazolone, 2,4,5,6-tetrachloroisophthalonitrile, tolylfluanid, dichlofluanid, diiodomethyl-pair Toluene sulfonate, capsciacin, N-cyclopropyl-N'-(1,1-dimethylethyl)-6-(methylthio)-1,3,5-triazine- 2,4-Diamine, 3-iodo-2-propynylbutylcarbamate, medetomidine, 1,4-Dithiazepine-2,3-dicarbonitrile (dithianon), borane such as pyridine triphenylborane, substituted at position 5 and optionally at position 1 Trihalomethyl-3-halo-4-cyanopyrrole derivatives such as 2-(p-chlorophenyl)-3-cyano-4-bromo-5-trifluoromethylpyrrole (tralopyril) And furanone such as 3-butyl-5-(dibromomethylene)-2(5H)-furanone and mixtures thereof, macrocyclic lactones such as avermectin, such as avermectin B1, ivermectin, doramectin, abamectin, amacectin and selamectin, and a quaternary ammonium salt such as chlorinated Mercaptodimethylammonium chloride and alkyldimethylbenzylammonium chloride. In one embodiment, the biocide can be 3-isothiazolone, although the inventors have discovered that the biocide should preferably be in encapsulated, adsorbed or bound form. In another embodiment, the biocide is not 3-isothiazolone.

The biocide is preferably organic or metal-organic. Without wishing to be bound by theory, it is believed that the leaching of the biocide involves the physical diffusion of the biocide from the first coating layer through the (or subsequent) coating layer by a passive transport process. Thus, the flux of biocide from the coating system will be controlled, in part, by the diffusion of the biocide through the (or subsequent) coating layer and compatibility with the subsequent coating layer. If the diffusion or compatibility is inherently high, as expected for organometallic biocides such as organotin and the like, the resulting leaching rate will also be inherently high and difficult to control, so that the life of the coating will be reduced. And can cause undesired environmental impact. If the diffusion or compatibility is inherently low, as would be expected for inorganic biocides such as inorganic copper salts and the like, the leaching rate will also be inherently low and can lead to fouling. In general, the use of organic or metal-organic biocides allows for the use of the present invention. The coating system is adapted to properly control the rate of leaching and to avoid unacceptable environmental damage.

In the context of the present invention, an inorganic biocide is a biocide containing a metal atom and containing no carbon atoms; the organometallic biocide is a biocide containing a metal atom, a carbon atom and a metal-carbon bond. A metal-organic biocide is a biocide whose chemical structure comprises a metal atom, a carbon atom and which does not contain a metal-carbon bond; and an organic biocide is a biocide whose chemical structure contains a carbon atom and does not contain a metal atom.

Preferably, in order to obtain excellent antifouling properties, the biocide is in position 5 and optionally in position 1 substituted 2-trihalomethyl-3-halo-4-cyanopyrrole derivative. One or more, such as bromnitrile, 1,4-dithiazepine-2,3-dicarbonitrile (nitrile sulfonium), copper pyrithione, zinc pyrithione, carbendazim, Yifaling and N-cyclopropyl-N'-(1,1-dimethylethyl)-6-(methylthio)-1,3,5-triazine-2,4-diamine.

Preferably, the (etc.) biocide is present in the first coating layer in an amount of from 0.05 to 50% by weight, more preferably from 3 to 30% by weight, and most preferably from 10 to 20% by weight (based on The total weight of the composition of the first coating layer). In any event, the amount of biocide present in the first coating layer must be greater than the amount of biocide in at least one subsequent coating layer when the coating layers are applied to the substrate.

In addition, the biocide may be encapsulated, adsorbed or supported or combined, in whole or in part, as appropriate. The handling of certain biocides is difficult or dangerous and it can advantageously be used in the form of encapsulation or adsorption or support or combination. In addition, the encapsulation, absorption or support or combination of the biocide can be provided for controlled killing The secondary mechanism of the leaching rate of the biocide from the coating system to achieve a more gradual release and long lasting effect.

The method of encapsulating, adsorbing or supporting or binding the biocide of the present invention is not particularly limited. Examples of methods by which the encapsulated biocide used in the present invention can be prepared include mono- and double-walled amine-formaldehyde or hydrolyzed polyvinyl acetate-phenolic resin capsules or microcapsules as described in EP1791424. An example of a suitable encapsulated biocide is encapsulated 4,5-dichloro-2-(n-octyl)-3(2H)-isothiazolone as described by Dow Microbial Control as Sea-Nine CR2 Marine Antifoulant Agent sales.

Examples of methods by which an absorbent or supported or bound biocide can be prepared comprise the use of a host-guest complex (such as the cage compound described in EP 0709358), such as the phenolic resin described in EP 0880892, for example A carbon-based adsorbent, or an inorganic microporous support (for example, amorphous vermiculite, amorphous alumina, pseudo-boehmite or zeolite described in EP 1115282) described in EP 1142477.

Where the polymerization system of the biocidal first coating layer composition is crosslinkable, the composition may optionally comprise a catalyst. Examples of suitable catalysts are the carboxylates of various metals such as tin, zinc, iron, lead, bismuth and zirconium. The salts are preferably long chain carboxylates such as dibutyltin dilaurate, dibutyltin dioctoate, iron stearate, tin(II) octoate and lead octoate. Additional examples of suitable catalysts include organic rhodium and organotitanium compounds and organophosphates such as bis(2-ethyl-hexyl)hydrogen phosphate. Other possible catalysts include chelating agents such as dibutyltin acetylacetonate. Further, the catalyst may include a halogenated organic acid having at least one [α] position relative to the acid group A halogen substituent on a carbon atom and/or at least one halogen substituent on a carbon atom relative to the [β] position of the acid group, or hydrolyzable to form a derivative of the acid under condensation reaction conditions.

Alternatively, the catalyst may be as described in WO 2007122325 A1, WO 2008055985A1, WO 2009106717A2, WO 2009106718A2, WO 2009106719A1, WO 2009106720A1, WO 2009106721A1, WO 2009106722A1, WO 2009106723A1, WO 2009106724A1, WO 2009103894A1, WO 2009118307A1, WO 2009133084A1, WO 2009133085A1, It is described in any of WO 2009156608 A2 and WO 2009156609 A2.

The catalyst of the biocidal first coating layer composition is preferably present in an amount of from 0.01 to 4% by weight based on the total weight of the coating composition.

Preferably, the biocidal first coating layer composition according to the present invention also includes one or more fillers, pigments, additional catalysts and/or solvents. Examples of suitable fillers are barium sulphate, calcium sulphate, calcium carbonate, vermiculite or citrate (such as talc, feldspar and china clay), aluminum paste/flakes, bentonite or other clays. Some fillers, such as fumed vermiculite, can have a thixotropic effect on the coating composition. The proportion of the filler may range from 0 to 25 wt% based on the total weight of the coating composition. The clay is preferably present in an amount of from 0 to 1% by weight, and the thixotropic agent is preferably present in an amount of from 0 to 5% by weight based on the total weight of the coating composition.

Examples of suitable pigments are black iron oxide, red iron oxide, yellow iron oxide, titanium dioxide, zinc oxide, carbon black, graphite, red molybdate, yttrium vanadate yellow, yellow molybdate, zinc sulfide, cerium oxide, cobalt oxide. /zinc titanium Green, zinc titanate/tin orange, sulphide orange and red, manganese violet pyrophosphate, sodium sulfosyl citrate, quinacridone, indigo blue, indigo green, black iron oxide, indanthrene blue, oxidation Cobalt aluminum, carbazole dioxazine, chromium (III) oxide, isoporphyrin orange, tolidiole, benzimidazolone, quinophthalone yellow, isoporphyrin yellow , tetrachloroisoindolinone and quinophthalone yellow. The proportion of the pigment may range from 0 to 10% by weight based on the total weight of the coating composition. Suitable solvents include aromatic hydrocarbons, alcohols, ketones, esters and mixtures of the above with one another or aliphatic hydrocarbons. Preferred solvents include methyl isoamyl ketone and/or xylene. The solvent is preferably present in an amount of from 10 to 40% by weight based on the total weight of the composition.

The composition may optionally comprise an adhesion promoting material, typically in an amount of from 0.01 to 0.5 wt%, based on the total weight of the composition. Examples of suitable adhesion promoters include decane such as amino decane, epoxy decane, methacryloxypropyl decane and decyl decane.

The adhesion promoter is preferably an amine decane of the type: (RO) _x R _3-x SiR ¹ N(R ² ) ₂ wherein each R is independently selected from a C1-8 alkyl group (eg methyl, ethyl) , hexyl, octyl, etc.), C1-4 alkyl, O, C2-4 alkyl; aryl (eg phenyl) and aryl C1-4 alkyl (eg benzyl); R ¹ selected from (CH ₂ ) _1-4 , methyl-substituted trimethylene and (CH ₂ ) _2-3 , O, (CH ₂ ) _2-3 ; R ² is selected from hydrogen, alkyl, cycloalkyl, aralkyl a aryl or aryl group or (CH ₂ ) _2-4 -NH ₂ .

Alternatively, the adhesion promoter is of the following type "dipodal" decane (R ³ O) ₃ SiR ¹ NHR ² Si(OR ⁴ ) ₃ or (R ³ O) ₃ SiR as mentioned in WO 2010018164 ¹ NHR ⁵ NHR ² Si(OR ⁴ ) ₃ wherein R ¹ , R ² and R ^{5 are} independently C1 to C5 alkyl and R ³ and R ⁴ are independently selected from methyl or ethyl.

Alternatively, the adhesion promoter is an epoxy decane of the following type: A-Si(R) _a (OR) _(3-a) wherein A is an epoxide-substituted monovalent hydrocarbon group having 2 to 12 carbon atoms; And each R is independently selected from C1-8 alkyl (eg, methyl, ethyl, hexyl, octyl, etc.), C1-4-alkyl-, O-, C2-4-alkyl; aryl (eg, Phenyl) and aryl C1-4 alkyl (eg benzyl); and a is 0 or 1.

The group A in the epoxy decane is preferably an alkyl group substituted with a glycidoxy group, such as 3-glycidoxypropyl. The epoxy decane may, for example, be 3-glycidoxypropyltrimethoxydecane, 3-glycidoxypropyltriethoxydecane, 3-glycidoxypropyldiethoxymethoxydecane, 2 - glycidyloxypropyltrimethoxydecane, 2-(3,4-epoxy-4-methylcyclohexyl)-ethyltrimethoxydecane, 5,6-epoxy-hexyltriethoxy Decane; or an oligomer thereof.

The adhesion promoter is more preferably N-2-aminoethyl-3-aminopropyltrimethoxydecane. Additional optional additives include dispersing agents such as unsaturated polyphthalate salts.

Subsequent coating layer, soil release layer

The composition of the (equal) subsequent coating layer is not particularly limited, but the composition preferably comprises a polymer. The polymer preferably forms an elastomer. More preferably, it is a polyorganosiloxane. Even more preferably, it is a polydimethyl siloxane. In addition, the polyorganosiloxane also comprises two or more polyorganosiloxanes of different viscosities. alkyl.

The polyorganosiloxane has one or more, preferably two or more such as a hydroxyl group, an alkoxy group, an ethyloxy group, a carboxyl group, a hydroquinone group, an amine group, an epoxy group, a vinyl group or a fluorene group. Reactive functional group.

Alternatively, the polymer may be as described in WO 2008132196, wherein the polymerization system is a polyorganosiloxane polyoxyalkylene block copolymer in the form of PS-(A-PO-A-PS)n, wherein PS represents A polyorganosiloxane block, PO represents a polyoxyalkylene block, A represents a divalent moiety and n has a value of 1 or greater.

The polymer has two or three reactive groups X per molecule of polyorganosiloxane block, which can self-condense and crosslink in the presence or absence of a catalyst (as previously defined in this document). It may optionally be crosslinked with another organic rhodium crosslinking agent containing two or more groups Y reactive with the groups X.

The (or other) polyorganosiloxane polymer is preferably present in an amount of from 30 to 90% by weight based on the total weight of the coating composition.

The polymer is preferably crosslinkable. The coating composition may require a crosslinking agent depending on the type of crosslinkable polymer. The presence of the crosslinking agent is only required if the curable polymer cannot be cured by condensation. This will depend on the type and amount of functional groups present in the polymer. If the polymer comprises an alkoxy-decyl group, the presence of a small amount of water and optionally a condensation catalyst is generally sufficient to achieve complete cure of the coating after application. For such compositions, atmospheric moisture is generally sufficient to induce curing, and typically will not require heating of the coating composition after application.

The crosslinking agent which may optionally be present may be a crosslinking agent comprising any one or more of a functionalized decane and/or an ethoxylated, alkoxy, decylamino, alkoxy and fluorenyl group. Examples of such crosslinkers are set forth in WO 99/33927, page 19, line 9 to page 21, line 17. Mixtures of different crosslinkers can also be used.

The crosslinking agent is preferably present in an amount of from 1 to 25 wt% based on the total weight of the coating composition.

Where the polymerization system of the subsequent coating layer composition is crosslinkable, the composition may optionally comprise a catalyst. Examples of suitable catalysts are the carboxylates of various metals such as tin, zinc, iron, lead, bismuth and zirconium. The salts are preferably long chain carboxylates such as dibutyltin dilaurate, dibutyltin dioctoate, iron stearate, tin(II) octoate and lead octoate. Additional examples of suitable catalysts include organic rhodium and organotitanium compounds and organophosphates such as bis(2-ethyl-hexyl)hydrogen phosphate. Other possible catalysts include chelating agents such as dibutyltin acetylacetonate. Further, the catalyst may comprise a halogen substituent having at least one carbon atom at a [α]-position relative to the acid group and/or at least one carbon atom at a [β]-position relative to the acid group. The halogenated organic acid of the halogen substituent may be hydrolyzed under condensation reaction conditions to form a derivative of the acid.

Alternatively, the catalyst may be, for example, WO 2007122325 A1, WO 2008055985A1, WO 2009106717A2, WO 2009106718A2, WO 2009106719A1, WO 2009106720A1, WO 2009106721A1, WO 2009106722A1, WO 2009106723A1, WO 2009106724A1, WO 2009103894A1, WO 2009118307A1, WO 2009133084A1. It is described in any of WO 2009133085A1, WO 2009156608A2 and WO 2009156609A2.

The catalyst is preferably present in an amount of from 0.05 to 4% by weight based on the total weight of the coating composition.

Preferably, the subsequent coating layer composition according to the present invention also comprises one or more fillers, pigments, catalysts and/or solvents. Examples of suitable fillers are barium sulphate, calcium sulphate, calcium carbonate, vermiculite or citrate (such as talc, feldspar and china clay), aluminum paste/flakes, bentonite or other clays. Some fillers such as fumed vermiculite may have a thixotropic effect on the coating composition. The proportion of the filler may range from 0 to 25 wt% based on the total weight of the coating composition. The clay is preferably present in an amount of from 0 to 1% by weight, and the thixotropic agent is preferably present in an amount of from 0 to 5% by weight based on the total weight of the coating composition.

Examples of suitable pigments are black iron oxide, red iron oxide, yellow iron oxide, titanium dioxide, zinc oxide, carbon black, graphite, red molybdate, yellow molybdate, zinc sulfide, cerium oxide, sodium sulfosilicate, Quinacridone, indigo blue, indigo green, black iron oxide, indanthrene blue, cobalt aluminum oxide, carbazole dioxazine, chromium oxide, isoindoline orange, bis-acetamidine-toluene Azole, benzimidazolone, quinacridone yellow, isoindoline yellow, tetrachloroisoindolinone, and quinophthalone yellow. The proportion of the pigment may range from 0 to 25 wt% based on the total weight of the coating composition. Suitable solvents comprise aromatic hydrocarbons, alcohols, ketones, esters and mixtures of the above with one another or aliphatic hydrocarbons. Preferred solvents include methyl isoamyl ketone and/or xylene. The solvent is preferably present in an amount of from 0 to 40% by weight, based on the total weight of the composition.

The soil release performance of the coating system of the present invention is generally improved when the (or) subsequent coating layer composition forms a substantially hydrophobic or amphiphilic soil release coating when dried or cured. The overall and surface hydrophobicity of the (or subsequent) coating layer can be characterized by a variety of methods, such as by seawater absorption measurements or surface contact angle measurements. The seawater absorption of the (equal) subsequent coating layer is preferably less than 30% by mass, more preferably less than 25% by mass. The equilibrium water contact angle of the (equal) subsequent coating layer is preferably greater than 30 degrees at 23 °C.

In a preferred embodiment, the (and subsequent) coating layer composition contains an incompatible fluid or grease. In the context of the present invention, an incompatible fluid means a polyoxo, organic or inorganic molecule or polymer, usually a liquid, but optionally an organic soluble grease or wax, and the subsequent coatings The layer (the elastomeric network) is immiscible (all or part). Once the first coating layer and the subsequent coating layer are cured, the fluid will be formed to be enriched on the surface of the (or subsequent) coating layer and enhance its soil release properties. Examples of incompatible fluids are provided in WO 2007/10274. In WO 2007/10274, a fluorinated polymer or oligomer in the incompatible flow system polyoxyalkylene coating; due to the difference in surface energy, the fluorinated polymer/oligomer is enriched in the cured polyfluorene The process of the surface of the oxyalkylene coating layer is thermally driven. The low surface energy provided by the fluorinated polymer or oligomer is combined with the elastomeric properties provided by the cured polyoxyalkylene to improve the soil release properties of the coating.

Examples of suitable fluids are: a) linear and trifluoromethyl branched fluorine terminated perfluoropolyethers (eg Fomblin Y®, Krytox K® fluid or Demnum S® oil); b) linear di-organic (OH) Blocked perfluoropolyether (eg Fomblin Z DOL®, Fluorolink E®); c) Low MW polychlorotrifluoroethylene (eg Daifloil CTFE® fluid).

In all cases, the polymer or oligomer containing a fluorinated alkyl or alkoxy group does not substantially participate in any crosslinking reaction. It is also possible to use other mono- and di-organic functional end-capped polymers or oligomers containing fluorinated alkyl or alkoxy groups (for example polymers containing carboxyl groups, ester functional fluorinated alkyl groups or alkoxy groups or low) Polymer).

Alternatively, the fluid may be a polyoxygenated oil, for example, of the formula: Q ₃ Si-O-(SiQ ₂ -O-) _n SiQ ₃ wherein each group Q represents a hydrocarbon group having 1 to 10 carbon atoms and the n system is such that The polyoxygenated oil has an integer of from 20 to 5000 mPa s. Typically at least 10% of the groups Q are methyl and at least 2% of the groups Q are phenyl. Most preferably, at least 10% of the -SiQ ₂ -O- units are methyl-phenyloxirane units. Most preferably, the polyoxyphthalic acid is a methyl terminated poly(methylphenyl siloxane). The oil preferably has a viscosity of from 20 to 1000 mPa s. Examples of suitable polyoxygenated oils are sold by Bluestar Silicones under the trademarks Rhodorsil Huile 510V100 and Rhodorsil Huile 550. The polyoxyxene oil improves the resistance of the coating system to aquatic fouling.

The fluid can also be an organopolyoxygen as shown below: among them:

- R1 may be the same or different and are selected from alkyl, aryl and alkenyl groups, depending on The case is substituted with an amine group, an oxygen-containing group of the formula OR5, wherein R5 is hydrogen or a C1-6 alkyl group and a functional group according to formula (I): -R6-N(R7)-C(O)-R8-C (O)-XR3 wherein: - R6 is an alkyl group selected from the group consisting of an alkyl group of 1 to 12 carbon atoms, a hydroxyalkyl group, a carboxyalkyl group, and a polyoxyalkylene group of up to 10 carbon atoms; - R7 is selected from the group consisting of hydrogen, 1 An alkyl group having 6 carbon atoms, a hydroxyalkyl group, a carboxyalkyl group, and a polyoxyalkylene group having 1 to 10 carbon atoms; R7 may be bonded to R8 to form a ring; - R8 has 1 to 20 carbon atoms An alkyl group; - R9 is hydrogen or an alkyl group having from 1 to 10 carbon atoms optionally substituted with an oxygen-containing or nitrogen-containing group; - X is selected from the group consisting of O, S and NH; At least one R1 group in the oxirane polymer is a functional group according to the above formula (I) or a salt derivative thereof; - R2 may be the same or different and is selected from the group consisting of an alkyl group, an aryl group and an alkenyl group; - R3 and R4 They may be the same or different and are selected from alkyl, aryl, capped or unblocked polyoxyalkylene, alkaryl, aralkyl and alkenyl; - a is an integer from 0 to 50,000; b is an integer from 0 to 100; and - a+b is at least 25. In one embodiment, -R2, R3 and R4 are independently selected from the group consisting of methyl and phenyl, more preferably methyl.

- R6 is an alkyl group having 1 to 12, more preferably 2 to 5 carbon atoms.

- R7 is hydrogen or an alkyl group having 1 to 4 carbon atoms.

- R8 is an alkyl group having 2 to 10 carbon atoms.

- R9 is hydrogen or an alkyl group having 1 to 5 carbon atoms.

- X-type oxygen atom.

- a+b is in the range of 100 to 300.

In one embodiment, the flow system is present from 0.01 to 10 wt% based on the total weight of the coating composition. The fluid is preferably present in the range of 2 to 7 wt%.

Method for controlling the release rate of biocide

According to the present invention, there is provided a method for releasing a controlled release coating systems of the kill rate of biocide from the soil, where 5 days after application of the coating from fouling release coating system the rate of release of the biocide (R ₅₎ and 30 days after application of the coating Ratio of release rate (R ₃₀ ) of biocide R ₅ /R ₃₀ 1.5. The method comprises: a. providing a substrate, b. coating the substrate with a first coating layer, c. applying at least one subsequent coating layer on top of the first coating layer, the first coating layer comprising a biocide The subsequent coating layer contains less biocide than the first coating layer and is free or substantially free of biocide.

In one embodiment, the method of the present invention is capable of controlling the rate at which the biocide is released from the soil release coating system such that the ratio R ₅ /R _{30 is} less than or equal to ( ) 1.33, and preferably less than or equal to ( ) 1.11.

The first coating layer and/or the (or subsequent) coating layer suitably comprises an elastomeric polymer. The elastomeric polymerization system is as described in all of the above paragraphs.

The first coating layer and/or the (or subsequent) coating layer suitably comprises a polyorganosiloxane. The (equal) subsequent coating layer is as described in all of the above paragraphs.

The substrate is suitably coated with a corrosion resistant coating and the first coating layer is used as a bonding coating on the corrosion resistant coating.

The biocide in the first coating layer is suitably an organic or metal-organic biocide. The biocide is as described in all of the above paragraphs.

The biocide is suitably any one or more of the above biocides, and is most suitably 2-trihalomethyl-3-halo-4- substituted at position 5 and optionally at position 1. A cyanopyrrole derivative or 1,4-dithiazepine-2,3-dicarbonitrile.

The (equal) subsequent coating layer suitably comprises an incompatible fluid, such as a polyfluorene oxide, an organic or inorganic molecule or polymer, which is immiscible with the (or subsequent) coating layer.

application

The coating system according to the present invention can be applied to the substrate by conventional techniques such as brushing, rolling, dip coating or spraying (no air and conventional).

After the (and subsequent) subsequent coating layer is cured, it can be immediately immersed and provide immediate protection against fouling and scale release. The resulting coating system has relatively good anti-fouling and scale release properties. This makes the coating system according to the invention extremely suitable for preventing fouling in marine and freshwater applications. The coating system can be used in dynamic and static structures such as boats and boats, buoys, drilling platforms, oil rigs, floating production storage and unloading vessels (FPSO), pipelines, power plants Cooling water inlets, fish nets, fish cages and other aquaculture and marine equipment/structures and their analogues that are fully or partially immersed in water. The coating system can be applied to any of the substrates used in such structures, such as metals (e.g., steel, aluminum), concrete, wood, plastic, or fiber reinforced resins.

The coating system of the present invention in addition to having a controlled release coating systems of the release rate of biocide from the soil, so that application of the coating system 5 days after the release coating of the release rate of biocide (R ₅₎ from dirt and application of the coating 30 The ratio of R ₃ /R ₃₀ of the release rate (R ₃₀ ) of the biocide is less than or equal to ( ) 1.5 (better) 1.33), it has also been found to be effective against (i) slime deposits, (ii) seagrass fouling, (iii) soft scale and (and) compared to systems that do not contain biocide or soil release coatings. Iv) A wide range of scale types of hard scale, especially in slow moving water containers.

The coating system can be applied directly to an untreated substrate. Alternatively, the coating system of the present invention can be applied to a substrate to which a surface treatment or other coating layer has been previously applied. Examples of such surface treatments and other coating layers include anti-corrosive coatings, biocidal anti-fouling coatings, seal coatings, adhesive coatings, adhesion promoting layers, and the like.

With regard to application to newly built boats and hulls, the system is typically applied directly to a substrate having one or more corrosion resistant coatings. When servicing and repairing or recoating, the mechanism is typically applied to existing coating mechanisms (with optional chain coatings) or the existing coating mechanism is removed and one or more corrosion resistant applications are applied. The coating layer is applied directly to the substrate.

The substrate to be inhibited from fouling is not particularly limited and includes any steel, plastic, concrete, wood, fiber reinforced resin, and aluminum.

Typically, for application to boats and hulls, a first coating layer will be applied to produce a dry film thickness in the range of 100 to 200 μm, and the (or) subsequent coating layer will be applied to produce between 100 and 200 Dry film thickness in the range of μm. When a larger dry film thickness is desired, the desired film thickness can be produced by sequential application, each having a dry film thickness of 100 to 200 μm. On other substrates, the first coating layer will be applied to produce a dry film thickness in the range of 50 to 500 μm, and the (or) subsequent coating layer will be applied to produce a dry film thickness in the range of 50 to 500 μm.

The invention will now be described with reference to the following examples. The invention is intended to be illustrative, and is not to be construed as limiting the scope thereof.

Instance Examples 1 to 8

Eight different coating systems (Examples 1 through 8) in accordance with the present invention were prepared.

The biocide leaching rate of each coating system was determined experimentally. In summary, the replication plates coated with each coating system are immersed in a storage tank for synthetic seawater. The plates were periodically transferred to a fresh synthetic seawater leaching rate measuring vessel and gently stirred for a fixed time. At the end of the period, the plates are returned to the hopper and the amount of biocide that has been leached into the container is determined by chemical analysis. The biocide leaching rate can be determined as expressed in μg cm ^-2 d ^-1 by knowing the measured amount of the leaching biocide, the exposed surface area of the coated plate, and the soaking time in the leaching rate measuring container.

Artificial seawater

Artificial seawater was prepared using commercially available Instant Ocean Sea Salt by mixing 33 g of salt per liter of deionized water.

Plate preparation

A 15 x 10 cm polycarbonate plate was masked to give a known surface area (typically about 100 cm ² ). A 125 μm dry film thickness of a 2-piece epoxy anti-corrosive coating (Intershield 300, International Paint) was applied by a lower drawbar, followed by application of a biocide-containing coating layer at a dry film thickness of 100 μm via a lower drawbar. After drying, a final "finish" coating was applied to the film via a lower drawbar at a dry film thickness of 15 μm (except for Example 5 using a dry film thickness of 100 μm). The masking tape was removed and the edges of the coated panels were sealed with a 2-piece epoxy anti-corrosion coating (Intershield 300, International Paint) using a brush. Each coating is cured under ambient conditions prior to application of the subsequent coating layer and prior to immersion in the hopper.

Storage tank

The plates were completely immersed in 40 liters of artificial seawater in an absolutely clean glass tank and water was constantly circulated through the activated carbon filter to avoid accumulation of biocide or its degradation products. The temperature of the hopper is maintained at about 22 to 23 °C. All plates remained immersed in the hopper during the experiment, except during the leaching rate measurement period using the leaching rate measuring container for the predetermined number of days of measurement.

Leach rate measuring container

At the scheduled measurement days, the plates were transferred to individual absolutely clean capped polypropylene containers (15 x 8 x 8 cm, l x w x h) containing 100 ml of artificial seawater at a temperature of about 22 to 23 °C. The containers were gently agitated using an orbital mixer for 2 hours and then the plates were returned to the hopper.

Leach rate determination - conventional

The concentration of biocide in the leaching rate measuring vessel can be determined using standard analytical methods known to those skilled in the art, such as high performance liquid chromatography (HPLC). The leaching rate can then be used to measure the concentration of biocide in the vessel, using the following equation to determine the leaching rate R.

Wherein C is the equivalent concentration of the biocide in the leaching rate measuring container, V is the volume of the artificial seawater in the leaching rate measuring container (liters), the soaking period (hours) of the t-plate in the leaching rate measuring container, and A The exposed surface area (cm ² ) of the coating system on the plate.

Example 1 to 8 leaching rate determination - bromine nitrile

At the end of the agitation period, about 12 ml of artificial seawater from each leaching rate measuring vessel was transferred to a glass vial. The vial was maintained at 45 ° C overnight to ensure quantitative conversion of the leached bromide to 3-bromo-5-(4-chlorophenyl)-4-cyano-1H-pyrrole-3-carboxylic acid (BCCPCA) ).

By using a Agilent 1100 HPLC system equipped with a Pursuit UPS 2.4 μm C18 column (50 x 3 mm) and using a mixture of acetonitrile, water and orthophosphoric acid in a volume ratio of 50:49.95:0.05 as a mobile phase via direct injection, The concentration of BCCPCA in the treated samples was determined by high performance liquid chromatography (HPLC).

A minimum of 6 calibration standards covering a range of 10 to 500 μg liter ^-1 are freshly prepared daily by appropriately diluting 1000 μg liter ^-1 stock solution of BCCPCA in tetrahydrofuran with artificial seawater. Artificial seawater blank samples were analyzed before and after the standards and after each sample set. The calibration standard was performed after every 5 samples to check the reproducibility of the analytical method. At each time point, it was confirmed that the analytical method was proved to be reproducible.

The equivalent concentration of bromospira in the leaching rate measuring vessel at the end of the stirring period is calculated by multiplying the measured BCCPCA concentration by the relative molar mass of bromospira and BCCPCA, and then calculating the bromospira according to the following equation Leach rate R: Wherein C _bromine nitrile is the equivalent concentration of bromospira in the leaching rate measuring container, V is the volume of artificial seawater in the leaching rate measuring container (liters), and the soaking period of the t-plate in the leaching rate measuring container (hours) And the exposed surface area (cm ² ) of the A-based coating system on the plate.

Table 3 shows the leaching rate results and R ₅ /R ₃₀ collected at the days of measurement 5 (R ₅ ) and 30 (R ₃₀ ). In each case, these results are the average of the replicated plates for each coating system.

It can be seen that each coating system exhibits controlled leaching as defined within the framework of the present invention, and none of these coatings exhibit biocide leaching rate behavior corresponding to the biocide leaching rate proportional to the square root of time. In addition, by varying the specific parameters of the (or subsequent) coating layer, the biocide leaching rate behavior can be controlled to increase, decrease, or substantially remain constant over time.

In addition, different average biocide leaching rates can be achieved and By varying the specific parameters of the subsequent coating layer, the biocide leaching rate can be controlled so that a higher or lower biocide leaching rate can be obtained at any given point in time.

¹⁾ : Biocide release rate after 5 days of soaking ²⁾ : Biocide release rate after 30 days of soaking

Examples 9 to 12

As shown in Table 4, additional coating systems (Examples 9 through 12) in accordance with the present invention were prepared for comparison with commercial biocide-free soil release coating systems (all examples).

Test plates were prepared to determine the ability of each coating system to control the biocide leaching from the first coating layer and inhibiting fouling. The coating systems of Examples 9 through 12 were applied to a 60 x 60 cm marine plywood panel by means of a roller to provide a dry film thickness of about 100 and 150 μm, respectively, of the first coating layer and the subsequent coating layer. The panels were pre-primed with one of two sets of epoxy anti-corrosive coatings (Intershield 300, International Paint), each having a DFT of about 125 μm. One half of each plate (left hand side) was coated with a coating system corresponding to one of the coating systems of Examples 9 to 12, and the other half of the plate (right hand side) was released with a commercial soil release adhesive coating (Intersleek 737, International Paint) ) Coating as a control. A standard soil release finish (Intersleek 757, International paint) was then applied to both sides. Each coating was fully cured under ambient conditions prior to application of the subsequent coating layer and prior to testing.

The test plate was simultaneously immersed in natural tropical seawater at a depth of 0.5 to 1.0 m in Singapore (the scale growth is known to be severe). The plates were periodically removed from the water, photographed and the scale growth on the coating system was evaluated before re-soaking the plates.

The coating system containing bromospirit (Example 9) and nitrile sulfonium (Example 10) remained substantially free of fouling even after 8 months of soaking. After 8 months, it contains pyridine The coating system of copper thione (Example 11) and zinc pyrithione (Example 12) exhibited more serious scale growth than Examples 9 and 10, but its fouling growth was less severe than the control coating.

In all cases, the coating systems of Examples 9 through 12 contained no bubbles and cracks after 8 months of soaking.

These results clearly show that the ability of the coating system according to the present invention to inhibit fouling over an extended period of time is significantly improved over standard commercial soil release coating systems.

Claims (15)

A structure coated with a biocidal soil release coating system obtained by: a. providing a substrate, b. coating the substrate with a first coating layer, c. at the top of the first coating layer Applying at least one subsequent coating layer, the first coating layer comprising a biocide, the (or subsequent) coating layer comprising less biocide than the first coating layer and which is free or substantially free of biocide, And the first and the (or subsequent) coating layers form a biocidal soil release coating system exhibiting controlled leaching of the biocide. The structure of claim 1, wherein the rate of release of the biocide from the soil release coating system after 5 days of application of the coating (R ₅ ) and the rate of release of the biocide after 30 days of application of the coating (R ₃₀ ) ₅ /R ₃₀ 1.5. The structure of claim 2, wherein the ratio R ₅ /R ₃₀ 1.33. The structure of any one of claims 1 to 3, wherein the first coating layer and/or the (or subsequent) coating layer comprises an elastomeric polymer. The structure of any one of claims 1 to 3, wherein the first coating layer and/or the (or subsequent) coating layer comprises a polyorganosiloxane. The structure of any one of claims 1 to 3, wherein the substrate is coated with an anti-corrosive coating and the first coating layer is used as a bonding coating on the anti-corrosion coating. The structure of any one of claims 1 to 3, wherein the biocide in the first coating layer is an organic or metal-organic biocide. The structure of claim 4, wherein the biocide in the first coating layer is an organic or metal-organic biocide. The structure of claim 7, wherein the biocide is a 2-trihalomethyl-3-halo-4-cyanopyrrole derivative substituted at position 5 and optionally at position 1, or 1,4- One or more of dithiazepine-2,3-dicarbonitrile. The structure of claim 8, wherein the biocide is a 2-trihalomethyl-3-halo-4-cyanopyrrole derivative or a 1,4-substituted group at position 5 and optionally at position 1. One or more of dithiazepine-2,3-dicarbonitrile. The structure of any one of claims 1 to 3, wherein the (equal) subsequent coating layer comprises an incompatible fluid. The structure of any one of claims 1 to 3, wherein the substrate is a structure of a maritime or aquaculture industry, such as a hull, a boat body, a buoy, a drilling platform, a production rig, a floating production storage and unloading container (FPSO) ), pipelines, power plant cooling water inlets, fish nets or fish cages. The structure of claim 4, wherein the substrate is a structure of a maritime or aquaculture industry, such as a hull, a boat body, a buoy, a drilling platform, a production rig, a floating production storage and unloading container (FPSO), a pipeline, a power plant. Cooling water inlet, fish net or fish cage. The structure of claim 6, wherein the substrate is a structure of a maritime or aquaculture industry, such as a hull, a boat body, a buoy, a drilling platform, a production rig, a floating production storage and unloading container (FPSO), a pipeline, a power plant. Cooling water inlet, fish net or fish cage. Coating a controlled release system releases the methods of killing rate of biocide from the soil, where 5 days after application of the coating system from the release coating soil release rate of biocide (R ₅₎ and application of the coating release biocide 30 days Rate of rate (R ₃₀ ) R ₅ /R ₃₀ 1.5. The method comprises: a. providing a substrate, b. coating the substrate with a first coating layer, c. applying at least one subsequent coating layer on top of the first coating layer, the first coating layer comprising a biocide The subsequent coating layer comprises less biocide than the first coating layer and is free or substantially free of biocide.