BATH AND PROCESS FOR THE PHOSPHATIZATION OF METALLIC SUBSTRATES, CONCENTRATES FOR THE PREPARATION OF SAID BATH AND METALLIC SUBSTRATES HAVING BEEN SUBJECTED TO A TREATMENT BY SAIDBATH AND PROCESS

摘要

The invention relates to a bath and to a processfor the phosphatization of metallic substrates as well asa metallic substrate having been subjected to saidtreatment by the said bath and process.The bath according to the invention, whose pH isfrom 1 to 5.5 and comprising the classical components ofthe phosphatization baths, is characterized by the factthat it comprises- from about 0.3 to about 25 g/l of zinc ion,preferably from 0.5 to 10 g/l,- from 5 to about 50 g/l of phosphate ion,preferably from 8 to 30 g/l, et- from about 0.01 to about 10 g/l, preferably from0.03 to 3 g/l of a trivalent cobalt complex represented byone of the formulae (I) or (II).No figure.