Abstract: The present invention relates to an anti-fouling coating composition that comprises a marine biocide and a binder which is a hydrolyzable film-forming seawater-erodible polymer. The polymer contains sulphonic acid groups in quaternary ammonium salt form.

Abstract: A coating composition comprising an anhydride polymer (A) containing at least two cyclic carboxylic acid anhydride functional groups and a polymer (B) containing at least two functional groups reactive with anhydride groups and selected from hydroxyalkylamino, hydroxyalkoxyalkylamino, hydroxysubstituted acyloxyalkylamino, hydroxysubstituted polyacyloxyalkylamino, mercaptoalkylamino and oxazolidino groups. One of the polymers (A) and (B) comprises at least one flexible polymer chain selected from polyether, polyester, silicone, diene polymer, hydrogenated diene polymer, polyurethane, polyisobutylene and polyacrylate chains. The functional groups characteristic of that polymer are each present as a terminal group at the end of a flexible polymer chain.