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:
Jul. 28, 1992
Filed:
Dec. 21, 1990
Hans-Fr Schmidt, Eurasburg, DE;
Helmut Hadwiger, Munich, DE;
Milan Prochazka, Munich, DE;
Eddy Roelants, Asse, BE;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
A solder resist and a positively-acting photoresist are successively applied on a surface-wide basis onto a printed circuit board, whereupon the photoresist is selectively exposed and developed in the region of plated-through holes and/or solder pads of a printed conductor pattern carried on the printed circuit board, preferably with the assistance of laser beams. Subsequently, the solder resist is stripped in the regions not protected by the photoresist, i.e. in the regions of plated-through holes and/or solder pads and, as a last step, the remaining photoresist is likewise stripped. The method is particularly suited for the application of a solder resist layer onto three-dimensional printed circuit boards since traditional mask techniques for structuring the solder resist cannot be employed with respect to three-dimensional printed circuit boards.