| abstract |
A pretreatment composition and a method for pretreating a metal substrate is disclosed. The method comprises:n (a) pretreating the metal substrate with a Group IV(b) metal ion, followed by (b) treating the substrate of (a) with a composition comprising:n (i) a Group IV(b) metal ion, (ii) a copper ion, (iii) a fluoride ion, and (iv) an organophosphonic acid, followed by n (c) electrodepositing a cationic electrodepositable composition on the metal substrate. |