Abstract: The present invention is directed to a method of preparing a substrate to improve the adherence of a metallic coating to the substrate and the product thereof. More particularly, a method of manufactiring a molded circuit board and unique circuit board produced thereby, is disclosed. A molding compound, such as an epoxy resin is blended with a plating additive, such as calcium carbonate that is relatively inert to the molding compound. The blended mix can then be molded into a desired shape which, for a printed circuit board, can be a relatively flat plate configuration with a recessed groove and hole formation pattern. The high relief areas of the circuit board can be masked with a protective material. The plating additive can then be chemically etched from the grooved recessed area and holes, for example, by a hydrochloric acid bath. Appropriate catalyst and accelerators can be applied to the recessed groove pattern before the protective mask material is removed.
Type:
Grant
Filed:
November 3, 1975
Date of Patent:
March 21, 1978
Assignee:
Metropolitan Circuits Incorporated of California
Inventors:
Edward A. Cuneo, Makoto Kato, Michael S. Wilson, Aaron L. Pinkerton