MIT EINER SELBSTREINIGENDEN BESCHICHTUNG BESCHICHTETES HEIZGERÄT

A heating device has metal walls which are at least partly covered with a self-cleaning coating having an outer layer in contact with ambient air, made of at least one oxidizing catalyst chosen from among the platinum oxides, and at least one inner layer (3) between the metallic support and the outer layer made of an oxidation catalyst chosen from the oxides of Group 1b transition elements. The catalyst in the outer layer is an oxide of palladium or platinum or a mixture of these. The catalyst in the inner layer is an oxide of copper, silver or a mixture of these. In particular, the outer layer is a palladium oxide and the inner layer a silver oxide, or the outer layer is a mixture of palladium oxide and silver oxide. The thickness of the outer layer, measured using the RBS method, is 10-500 nm, preferably 20-120 nm. The thickness of the inner layer, measured using the RBS method, is 20-50 nm. An additional intermediate layer (5) can be placed between the metallic support and the inner layer, forming a catalytically inert support made of aluminum, enamel, polytetrafluoroethylene or a mixture of these. The intermediate layer is made of enamel. The device is in the shape of a cooking device with walls which are prone to be in contact with organic dirt and the coating covers these walls. An Independent claim is included for coating the metallic support of a heating device with a self-cleaning coating as described above, by (i) heating the surface of the metallic support to 400degreesC, (ii) placing it in contact under infrared at 400-600degreesC for several seconds, (iii) spraying a solution of a catalytic precursor to form the inner layer, (iv) reheating the surface in an oven to ca. 400degreesC, (v) placing it again under infrared at 400-600degreesC for several seconds, spraying a solution of a catalytic precursor to form the outer layer, and (vii) reheat the metallic support with infrared for several minutes.