Properties of metallocene complexes during the oxidative crosslinking of air drying coatings

Driers are added to air drying paints to accelerate the hardening of spread coating. For decades cobalt octoate has been the most widely used drier because of its good performance at ambient temperature. Recently, several reports describing possible carcinogenity and genotoxicity of cobalt and cobalt salts, such as cobalt sulfate in aerosols, have appeared. It is necessary to reduce the amount of cobalt compounds in coatings industry. Present study deals with the possibility of using ferrocene and its derivatives as driers for air drying coatings. We concentrated particularly on the synergic effect between these metallocene complexes and the cobalt drier. In the first step the kinetics of autooxidation by FTIR spectroscopy in model systems was investigated. Then the metallocene complexes were applied together with cobalt drier to alkyd resin, where their influence on hardness of spread coatings was examined.