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:
Oct. 15, 1985
Filed:
Sep. 21, 1984
Werner Rausch, Oberursel, DE;
Gerhard Muller, Hanau am Main, DE;
Metallgesellschaft Aktiengesellschaft, Frankfurt, DE;
Abstract
A process of electrodepositing zinc on steel wherein zinc-containing aqueous sulfuric acid electrolytes are used which contain one or more oxyacids of sulfur in which the sulfur has an oxidation number from +5 to +1. The phosphatizing of the resulting zinc coatings results in phosphate coatings which are virtually free of spots. Suitable oxyacids are sulfurous acid (H.sub.2 SO.sub.3), sulfoxylic acid (H.sub.2 SO.sub.2), hyposulfurous acid (H.sub.2 S.sub.2 O.sub.4) and/or thiosulfuric acid (H.sub.2 S.sub.2 O.sub.3) in the form of acids, salts and acid anhydrides. The oxyacids should be present in the electrolyte in a concentration of 0.05 to 10 g/l, preferably 0.1 to 2 g/l.