Rust preventing coating composition

摘要

A rust preventive coating composition having a long pot life and providing a coating in which generation of white rust is greatly reduced, said coating composition being obtained by incorporating a small amount of at least one salt selected from the group consisting of molybdate salts, tungstate salts, phosphomolybdate salts and phosphotungstate salts into a coating composition comprising as main components an alkali metal silicate or ammonium silicate and zinc powder.