초록 ▼

A process of making printed circuit boards in which the individual substrates involved are hot set formed from a suitable thermosetting resin and filler composition, with the cure being limited to the resin B stage. The side surfacing of the individual substrates that is to bear the metallic electri

A process of making printed circuit boards in which the individual substrates involved are hot set formed from a suitable thermosetting resin and filler composition, with the cure being limited to the resin B stage. The side surfacing of the individual substrates that is to bear the metallic electrically conductive circuiting is catalyzed and then electrolessly plated with copper or the like electrically conductive metallic material to a thickness in the range of from about 50 to about 100 millionths of an inch, and thereafter the thusly plated substrates are hot set to fully cure same and perfect the bond between the substrate and its plating. Each substrate then has a masking and non-conductive resist applied to its plated side (that is to bear the circuit), in a pattern that defines the printed circuit configuration and exposes the underlining electroless plating in the configuration of the circuit for electroplating, after which the substrate is electroplated with copper or the like in the circuit defining voids of the resist thereafter, the resist is stripped from the substrate, and the electroless plating thereby exposed is removed by etching.

대표청구항 ▼

In the method of making printed circuit boards that are to include a dielectric substrate having printed circuitry applied thereto in a pattern defined by a film of electrically conductive metal electrolessly plated on the substrate that is electroplated over in conformity to such pattern, with the

In the method of making printed circuit boards that are to include a dielectric substrate having printed circuitry applied thereto in a pattern defined by a film of electrically conductive metal electrolessly plated on the substrate that is electroplated over in conformity to such pattern, with the remainder of the film being etch removed from the substrate, the manner of making the substrate which comprises the steps of: hot setting a thermosetting resin and filler mixture to form and cure the substrate in planar configuration defining opposed side faces forming the substrate side surfacings, with the cure being limited to the resin B stage cure, catalyzing at least one side surfacing of the substrate, then electrolessly plating said substrate one side surfacing with the film of electrically conductive metal, then taking a plurality of said substrates, stacking them with elastomeric sheets in intercalated relation therebetween, with one of said elastomeric sheets engaged with each said one side surfacing, in coextensive relation therewith, for each substrate in the stack, and subjecting said stack to compressive pressure, acting normally of said substrates and said sheets, and heat, to hot pressure set said substrates to cure same through their C stage cure, while, in the case of each substrate, compressing said film thereof against said one side surfacing thereof with uniform pressure over said one side surfacing thereof through the elastomeric sheet engaging same.