Biocidal foul release coating systems

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.

1 - 11 . (canceled) 
     
     
         12 . A 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 formed from a coating composition containing a biocide, the at least one subsequent coating layer formed from a subsequent coating composition containing less biocide than the coating composition forming the first coating layer and which is free or substantially free of biocide, and wherein the first and the at least one subsequent coating layers form a biocidal foul release coating system, and wherein at least one of the first coating layer and the at least one subsequent coating layer comprise a polyorganosiloxane.   
     
     
         13 . The structure according to  claim 12 , wherein the ratio of the release rate of biocide from the foul release coating system 5 days after application of the coating (R 5 ) and the release rate of biocide 30 days after application of the coating (R 30 ) R 5 /R 30 ≦1.5. 
     
     
         14 . The structure according to  claim 13 , wherein the ratio R 5 /R 30 ≦1.33. 
     
     
         15 . The structure according to  claim 12 , wherein at least one of the first coating layer and the at least one subsequent coating layer comprises an elastomeric polymer. 
     
     
         16 . The structure according to  claim 12 , wherein the substrate is coated with an anticorrosion coating and the first coating layer is used as a tie coat over said anticorrosion coating. 
     
     
         17 . The structure according to  claim 12 , wherein the biocide in the first coating layer is an organic or metal-organic biocide. 
     
     
         18 . The structure according to  claim 12 , wherein the biocide is one or more of a 2-trihalogenomethyl-3-halogeno-4-cyano pyrrole derivative substituted in position 5 and optionally in position 1 or a 1,4-dithiaanthraquinone-2,3-dicarbonitrile. 
     
     
         19 . The structure according to  claim 12 , wherein the at least one subsequent coating layer comprises an incompatible fluid. 
     
     
         20 . The structure according to  claim 12 , wherein the substrate is a marine or an aquaculture structure. 
     
     
         21 . The structure according to  claim 20 , wherein the marine or aquaculture structure is a ship hull, a boat hull, a buoy, a drilling platform, an oil rig, a floating production storage and offloading vessel (FPSO), a pipe, a cooling water intake in a power plant, a fish net or a fish cage. 
     
     
         22 . A method of controlling the rate of release of biocide from a foul release coating system, the method comprising
 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 formed from a coating composition containing a biocide, the at least one subsequent coating layer formed from a subsequent coating composition containing less biocide than the coating composition forming the first coating layer and which is free or substantially free of biocide,   wherein the ratio of the release rate of biocide from the foul release coating system 5 days after application of the coating (R 5 ) and the release rate of biocide 30 days after application of the coating (R 30 ) R 5 /R 30 ≦1.5.   
     
     
         23 . The structure according to  claim 13 , wherein at least one of the first coating layer and the at least one subsequent coating layer comprises an elastomeric polymer. 
     
     
         24 . The structure according to  claim 13 , wherein the substrate is coated with an anticorrosion coating and the first coating layer is used as a tie coat over said anticorrosion coating. 
     
     
         25 . The structure according to  claim 13 , wherein the biocide in the first coating layer is an organic or metal-organic biocide. 
     
     
         26 . The structure according to  claim 15 , wherein the biocide in the first coating layer is an organic or metal-organic biocide. 
     
     
         27 . The structure according to  claim 13 , wherein the biocide is one or more of a 2-trihalogenomethyl-3-halogeno-4-cyano pyrrole derivative substituted in position 5 and optionally in position 1 or a 1,4-dithiaanthraquinone-2,3-dicarbonitrile. 
     
     
         28 . The structure according to  claim 16 , wherein the biocide is one or more of a 2-trihalogenomethyl-3-halogeno-4-cyano pyrrole derivative substituted in position 5 and optionally in position 1 or a 1,4-dithiaanthraquinone-2,3-dicarbonitrile. 
     
     
         29 . The structure according to  claim 13 , wherein the at least one subsequent coating layer comprises an incompatible fluid. 
     
     
         30 . The structure according to  claim 15 , wherein the at least one subsequent coating layer comprises an incompatible fluid. 
     
     
         31 . The structure according to  claim 13 , wherein the substrate is a ship hull, a boat hull, a buoy, a drilling platform, an oil rig, a floating production storage and offloading vessel (FPSO), a pipe, a cooling water intake in a power plant, a fish net or a fish cage.