Multilayer antisticking coating of improved hardness for aluminium support, articles and kitchen utensils having this coating

摘要

A hard non-stick multilayer coating for aluminum comprises a hard alumina-based layer, formed by micro-arc anodizing of the aluminum in an alkaline solution, and a layer based on polytetrafluoroethylene (PTFE) and chemical agents for forming an anchoring primer for one or more PTFE finishing layers. Independent claims are also included for (i) an aluminum or aluminum alloy article having a coating as described above; and (ii) an aluminum or aluminum alloy culinary utensil having a coating as described above. Preferred Feature: The hard layer is 5-100 mu thick and consists of alpha alumina and gamma alumina covered with a mullite layer. The primer and finishing layers have a thickness of 5-50 mu .