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:
Oct. 18, 1977
Filed:
Dec. 22, 1976
Robert William Peiffer, Jackson, NJ (US);
E. I. Du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
Printed circuit boards with plated through-holes are prepared by an electroless plating process using a self-supported, adherent, photohardenable sheet. The self-supported photohardenable sheet preferably is composed of a photopolymerizable material and may be a thick, homogeneous sheet or it may be a sheet reinforced with a foraminous material therein. The self-supported sheet is imagewise exposed to actinic radiation to form an adherent circuit pattern thereon comprising the unexposed areas. Through-holes are introduced into the pad areas of the circuit pattern, powdered catalyst is applied to the adherent pattern and through-holes and the catalytic image is plated in an electroless plating bath. The self-supported sheet may be used without additional catalyzing steps to make single sided, two-sided or multilayered printed circuit boards with plated throughholes and interconnections.