Core-shell pigments in antifouling paints

Marine fouling is the result of the settling and subsequent growth of organisms on surfaces immersed in seawater, Fouling of ships' hulls has been traditionally controlled through the use of toxic antifouling paints, but increased ecological awareness and the strict regulations of biocides used in such paints have led to the development of low toxic content or non-toxic coatings to control fouling. Results of investigations on the performance of five antifouling formulations in exposure trials carried out at Mar del Plata harbour (Argentina) are presented. The tests have revealed that these paints, which were formulated with a combination of a thin layer or shell of toxic pigment (cuprous thiocyanate) surrounding a core particle of non-toxic pigment (herein termed core-shell pigments), prevented the settlement of foulers, reducing costs and marine pollution.