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:
Jan. 17, 1989
Filed:
Jan. 12, 1988
Applicant:
Inventor:
Jean-Francois Paulet, Siblingen, CH;
Assignee:
Swiss Aluminium Ltd., Chippis, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C25D / ;
U.S. Cl.
CPC ...
204 376 ; 204 58 ; 204228 ; 204D / ; 204D / ;
Abstract
In processes for electrolytically dyeing anodic oxide layers on aluminum or aluminum alloys with direct or alternating current in electrolytes containing metal salts, high requirements are imposed on the uniformity of the dyeing and on the dyeing rate. The improvement of the uniformity of the dyeing and an increased dyeing rate can be achieved by pretreating the oxide layer by means of asymmetric alternating current before it is dyed. Such a process is preferably used in combination with an Sn-containing electrolyte.