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:
Nov. 19, 1991
Filed:
Sep. 24, 1990
Lawrence R Daley, Lexington, KY (US);
Gerald G Leslie, II, Lexington, KY (US);
International Business Machines Corp., Armonk, NY (US);
Abstract
Transfer printing from pad (9) is made in a pattern of resist (15) which covers a via (3) on a circuit board (1) metalized with a continuous copper layer (7). After transfer of resist material (14) to the pad, the pattern on the pad is hardened enough to be self-supporting by applying moderate radiation or allowing solvent to escape from the resist on the pad. The resist is transferred from the pad to the circuit board (1) and is then fully hardened, and the circuit board is immersed in etchant to remove unprotected copper (7). Copper in the covered vias is protected and therefore separate metalizations of vias is avoided. Since pad printing is particularly useful in general with three dimensional circuit boards, the use of pad printing to avoid separate metalization of vias is economic since it involves little additional to the general use.