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:
Sep. 27, 1977
Filed:
Aug. 22, 1975
Hajime Inoue, Kamakura, JA;
Fumio Harada, Yokohama, JA;
Kazunobu Kato, Yokohama, JA;
Syoji Oikawa, Yokohama, JA;
Hitachi, Ltd., , JA;
Abstract
After copper of printed circuit board lined with copper foil is etched with an acidic etching solution containing chloride ions, the resulting etching solution containing copper ions is placed in a cathode compartment partitioned with a diaphram from an anode compartment, while placing a caustic soda solution in the anode compartment, and subjected to electrolysis. In the cathode compartment, copper is deposited on an electrode without any redissolution of the deposited copper, and recovered, whereas in the anode compartment chlorine formed on an anode is absorbed into the caustic soda solution without any discharge to the atmosphere. The etching solution thus freed from the copper ions is admixed with the same kind of chemicals as consumed by the etching, and used again as a regenerated etching solution.