| 摘要 |
<p>The present invention addresses the problem of providing a chrome-free coating composition and metal plates coated with the coating composition, said chrome free coating composition: being capable of forming a coating film with excellent corrosion resistance not only on the general parts of a coated metal plate, but on processed parts and the ends; and being particularly effective in improving the corrosion resistance of steel sheets that have not been subjected to plating, or steel sheets subjected to plating composed mainly of aluminum. As a means of solving such a problem, a coating composition containing (A) a coating film-forming resin containing a hydroxyl group, (B) a cross-linker, and (C) an anti-corrosive pigment mixture is provided, said coating composition being characterized in that the anti-corrosive pigment mixture (C) comprises: (1) at least one type vanadium compound selected from a group comprising vanadium pentoxide, calcium vanadate, magnesium vanadate, and ammonium metavanadate; (2) a phosphoric acid-containing metal salt containing at least magnesium, said salt being a salt of at least one type of acid selected from a group comprising phosphoric acid, phosphorous acid, and triphosphoric acid; and (3) silica with magnesium ion exchanging capacity.</p> |
