The present invention relates to a coating composition containing 0.1 to 50 parts by weight of (A) an organosilicate and/or its condensates per 100 parts by weight of a resin solid content in the coating composition, and 0.1 to 50 parts by weight of (B) an acid surface active agent or a boric acid compound per 100 parts by weight of a solid content of the component (A).