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:
Mar. 04, 1986
Filed:
Mar. 29, 1985
Applicant:
Inventors:
John K Dorey, II, Ewing Township, Mercer County, NJ (US);
James T Huneke, Lower Makefield Township, Bucks County, PA (US);
Bruce S Madsen, Nockamixon Township, Upper Bucks County, PA (US);
Theodore F Schaaf, Lawrence Township, Mercer County, NJ (US);
Assignee:
AT&T Technologies, Inc., Berkeley Heights, NJ (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B44C / ; C03C / ; B05D / ; B29C / ;
U.S. Cl.
CPC ...
156655 ; 156668 ; 156902 ; 427 96 ; 427304 ; 427305 ; 427307 ;
Abstract
In a method for making a printed circuit board employing an aqueous type photoresist and including etching of the substrate surface with chromic acid after application of the photoresist mask, chromium is washed from the surface with a reducing agent at a pH of .ltoreq.10.