PROCEDURE FOR OBTAINING PHOSPHATE METALLIC SURFACES IN NON-AQUEOUS PHOSPHATE BATHS.

摘要

A process for phosphating metallic surfaces in nonaqueous phosphating baths comprising low-boiling halogenated hydrocarbons, aqueous phosphoric acid as the phosphating agent, alcohols as the solubilizer, and, optionally, further known components, e.g., stabilizers, inhibitors, or accelerators, comprising dipping the workpieces to be phosphated at least twice for at least 10 seconds into the boiling phosphating bath and, in the interval, leaving them for at least 20 seconds in the gaseous phase.