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:
Feb. 03, 1998
Filed:
Dec. 20, 1996
Stefan Hoveling, Osnabruck, DE;
Dirk Rode, Osnabruck, DE;
Helmut Protzer, Osnabruck, DE;
Ruzica Luetic, Osnabruck, DE;
KM Europa Metal Aktiengesellschaft, Osnabruck, DE;
Abstract
A passthrough method is provided in which the surface of an industrial grade, low-grease precursor made of copper, with a defined surface roughness, is patinated. For this purpose the precursor material, connected as the anode, is passed through an electrolysis bath, containing sodium carbonate and/or sodium hydrogencarbonate as well as sodium sulfite and/or sodium disulfite, with a temperature of 30.degree. C. to 90.degree. C. and a current density of 1 A/dm.sup.2 to 20 A/dm.sup.2 as bath parameters, for a residence time of 10 seconds to 12 minutes. The precursor material is rinsed and then moved through a fixing bath at a temperature of 35.degree. C. to 95.degree. C. for a residence time of 10 seconds to 120 seconds, and lastly, after a further rinsing, is dried. The fixing bath contains at least one of the oxidation agents: hydrogen peroxide (H.sub.2 O.sub.2), potassium chlorate (KClO.sub.3), potassium peroxodisulfate (K.sub.2 S.sub.2 O.sub.8), potassium permanganate (KMnO.sub.4), of copper sulfate (CuSO.sub.4.5H.sub.2 O).