Process and composition for treating phosphated metal surfaces.

摘要

Phosphated metal surfaces, particularly those which are iron-based or zinc-based, are treated, especially prior to cationic electrocoating, with an aqueous solution containing: (a) at least 0.05 g/l (as ZrO2) of water-soluble fluorozirconium compound; and (b)at least 0.05 g/l of myo-inositol phosphate and/or water-soluble salt thereof; the aqueous solution having a pH in the range 3 to 7, and the molar ratio of (a) to (b) being in the range 1:1 to 50:1.