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:
Feb. 28, 1978
Filed:
Aug. 09, 1976
Perstorp AB, Perstorp, SW;
Abstract
In a process for the production of a multilayer printed board built up by starting from a desired number of insulating bases clad on both sides with an unpatterned metal layer, the improvement consisting in that the metal layers, whereout conductive patterns are to be etched and which layers are to be hidden inside the finished multilayer printed board, are coated with a plating resist in the shape of a negative of the desired conductive pattern, that the remaining visible parts of the metal layers, which are to form the conductive patterns, are coated by electroplating with a thin, rough, adhesion-promoting metal layer comprising copper, zinc, nickel, tin or any one of their alloys, that an etch resist layer of nickel, tin or any one of their alloys is electroplated on top of the adhesion-promoting layer, if the latter consists of copper, zinc or any one of their alloys, that the negative plating resist is removed, that the parts of the metal layers thus uncovered are etched away and that the insulating bases provided with conductive patterns are laminated to a multilayer printed board.