Heated tool for used with a form for molten plastic or metal has core separated from electrical conducting ceramic coating by layer of electrical insulation

摘要

A heated tool used with a form for molten plastic or metal consists of a substrate material with a coating of electrically-conducting ceramic material with a cavity surface. The substrate is separated from the ceramic material by a layer of electrical insulation that is rendered free of distortion and fissures by thermal oxidation. The thermal insulation layer is a polymer e.g. Polyimide (PI), liquid crystalline polymer (LCP), polyetherketone (PEK) or polyethersulfone (PES), applied as a self-adhesive foil. In an alternative embodiment the insulating layer is a pressure setting plastic, laminar materials, or is applied by plasma or chemical vapour deposition. The insulation material properties are similar to those of the ceramic material. The insulation material is less than 0.15 mm thick.