Method for high-speed production of metal-clad articles

摘要

A die used for plastic injection molding is masked on its inner surface with a plating resist to leave only a selected area exposed. A conforming anode is fit into the die leaving a small clearance between the die cavity surface and the anode. A metal layer is electroplated onto the exposed mold surfaces of the die in less than a minute by using a high current density and a turbulent flow of electroplating solution. The die is then assembled with a second die to form a mold. A plastic molding composition is injected into the mold cavity and comes in contact with and adheres to the metal electroplate more tightly than the metal electroplate adheres to the surface of the mold member. As the mold is separated, the metal electroplate remains bonded to the plastic molding composition to form a metal-clad plastic article. Adhesion between the metal electroplate and the plastic can be improved by forming nodular growths on the metal electroplate. This is done by varying the current density and/or the electroplating solution flow-rate near the end of the electroplating process. The electroplating and molding steps may be sequentially combined into an automated process for the continuous production of metal-clad articles.