摘要 |
<p>The anticorrosive properties of a coating autodeposited on a metal substrate are improved by contacting the autodeposited coating with an aqueous solution containing Group IIA or Group IIB metal cations (e.g., calcium or zinc cations) and phosphate anions prior to curing. The rinse solution is preferably acidic and can be prepared, for example, from calcium nitrate and an oxy acid of phosphorus or zinc dihydrogen phosphate. Optionally, the rinse solution also includes an accelerator such as hydroxylamine.</p> |