摘要 |
An improved metal coating for a video disc of a grooved polymer disc, a conductive metal coating thereon and a dielectric coating on said metal coating comprising a trilayer film of a first layer of copper about 25-50 angstroms thick, a second layer about 200 angstroms thick of an alloy of nickel, and chromium and, optionally, iron, containing from about 20 to about 30 atomic percent of oxygen, and a third layer, of copper, about 25-50 angstroms thick. |