process for the preparation of coatings of zinc phosphate crystal surfaces of steel and zinc and zinc phosphating solution, which will be used in the process

摘要

The quality of a crystalline zinc phosphate conversion coating deposited on a ferrous or zinciferous surface from an aqueous, acidic, non-gassing phosphating solution is improved by the addition thereto of a polymeric additive which is an addition copolymer of an unsaturated carboxylic acid and a selected ethylenic monomer.