Method of making a printed circuit board

Abstract

Adhesive is applied to a substrate for a printed circuit board in a pattern corresponding to that of the printed circuit. If the adhesive is of the type which contains a solvent, the substrate and adhesive are heated after application of the latter in order to drive off the solvent. Subsequently, a thin foil of a material which is capable of bonding to a chemically deposited metal is pressed onto the adhesive. The adhesive is then permitted to set which causes those portions of the foil in contact with the adhesive to adhere tightly to the latter. Once the adhesive has set, the foil is peeled from the adhesive. The portions of the foil which contact the adhesive remain bound to the adhesive thereby forming a base which is capable of receiving a chemically deposited metal. The thus-coated substrate is immersed in a bath where an electrically conductive metal for forming the printed circuit is chemically deposited in a pattern corresponding to that of the adhesive and, consequently, of the printed circuit.

Dependencies are inferred from the claim text.