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:
Dec. 30, 1986
Filed:
Aug. 12, 1985
Applicant:
Inventor:
Norvell J Nelson, Palo Alto, CA (US);
Assignee:
Psi Star, Hayward, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
C23F / ; B44C / ; C03C / ; C03C / ;
U.S. Cl.
CPC ...
156656 ; 1566591 ; 156666 ; 156902 ; 252 792 ; 252 794 ;
Abstract
Process and solution for etching copper, for example, to remove it from printed circuit boards. The etching is effected by an aqueous solution of nitric acid, a polymer which inhibits undercutting of the copper, a surfactant, and sulfuric acid and/or an alkane sulfonic acid such as methane sulfonic acid.