The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 25, 1989
Filed:
Oct. 20, 1987
Metallgesellschaft Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
Disclosed is a process of producing a phosphate coating on a metal having a surface which consists at least in part of iron or steel. The metal is contacted at a temperature in the range from 30.degree. to 50.degree. C. with a phosphatizing solution which contains 5 to 25 g/l zinc, 1 to 10 g/l manganese, 0.1 to 13 g/l iron(II), 5 to 40 g/l phosphate (calculated as P.sub.2 O.sub.5), 5 to 50 g/l nitrate, and which also contains 0.5 to 5 g/l fluoroborate (calculated as BF.sub.4), and 0.05 to 3 g/l tartaric acid and/or citric acid. The solution has been adjusted to weight ratios of Zn:P.sub.2 O.sub.5 =(0.5 to 3):1 and of Mn:Zn=(0.04 to 0.5):1 and to a ratio of free acid to total acid of (0.04 to 0.2):1. It is preferred to add nickel, copper and/or calcium to the phosphatizing solution and to adjust it to a content of Fe(II) not in excess of 10 g/l. The process is particularly suitable for preparing metals for cold working.