Method for controlled release of compounds having antimicrobial activity and coating composition

A method for releasing a compound having antimicrobial activity from a matrix at a controlled rate which comprises incorporating an enzyme and a substrate in said matrix beforehand to allow said enzyme and said substrate to react with each other in said matrix to thereby produce said compound having antimicrobial activity, wherein said matrix is a paint film on the surface of structures exposed to water and said compound having antimicrobial activity is a compound having antifouling activity which is to be released into said water,

• and said substrate is at least one member selected from the group consisting of an ester bond-containing compound, an amide bond-containing compound, aliphatic alcohol, aromatic alcohol, aliphatic amine, and chitosan.

A coating composition comprising a film-forming resin, an enzyme, and a substrate, wherein said film-forming resin is a paint film-forming resin and said enzyme reacts with said substrate to produce a compound having antimicrobial activity, and wherein said substrate is at least one member selected from the group consisting of an ester bond-containing compound, an amide bond-containing compound, aliphatic alcohol, aromatic alcohol, aliphatic amine, and chitosan.