Metal surface treatment

摘要

Disclosed is a method of coating a metal surface by contacting it with an aqueous acidic solution containing hexavalent chromium and either a non-ionic surfactant having the formula RO(CH2CH2O)nH wherein R = a saturated or unsaturated aliphatic radical of 5 to 25 carbon atoms N = 2 TO 30 OR GLYCINE FOLLOWED BY DRYING AND BAKING THE SURFACE. Preferably, the solution also contains urea.