Production of a chromium-containing passivating layer on a metal surface comprises producing a solution containing complexed chromium ions, producing an acidic solution and applying to the metal surface

摘要

Production of a chromium-containing passivating layer on a metal surface comprises producing a solution containing complexed chromium (III) ions to which are mixed a chromium source, a phosphate source and a complex former to form chromium (III) complexes, producing an acidic solution and applying the acidic solution to the metal surface producing the passivating layer. Independent claims are also included for the following: (1) Material mixture containing a chromium (III) complex; and (2) Passivating layer produced by the above process.