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:
Aug. 21, 1990
Filed:
Jan. 23, 1989
Daniel P Walsh, Peabody, MA (US);
Philip D Knudsen, South Berwick, ME (US);
Polyonics Corporation, Newburyport, MA (US);
Abstract
Bath surfaces of a polyimide sheet are coated with a layer of electroless nickel or cobalt which can also include a thin electroless copper layer on the Ni. or Co. This tenaciously bonded coating is subsequently treated in such a way so as to increase its permeability or porosity without substantially altering its resistive properties. The induced porosity allows water and other volatiles trapped in the dielectric polyimide sheet to be removed while the preserved electrical continuity of the metal layer is sufficient to support electrolytic copper plating which services the dual purpose of providing a copper thickness useful for the subsequent production of electronic circuitry and preventing the readsorption of water into the dielectric core by permanently sealing or coating said porous metal layer.