초록 ▼

A heating appliance including a metal substrate, at least a part of which is covered with a self-cleaning coating including at least one oxidation catalyst selected from the platinoid oxides, and at least one dopant of said oxidation catalyst selected from the rare-earth oxides. The self-cleaning co

A heating appliance including a metal substrate, at least a part of which is covered with a self-cleaning coating including at least one oxidation catalyst selected from the platinoid oxides, and at least one dopant of said oxidation catalyst selected from the rare-earth oxides. The self-cleaning coating is a bilayer coating including: an inner layer at least partially covering the metal substrate and including the dopant; and an outer layer in contact with the ambient air and including the oxidation catalyst. Also provided is a method for producing such a heating appliance.

대표청구항 ▼

1. A heating appliance comprising a metal support, at least a portion of which is covered with a self-cleaning coating in contact with the ambient air, said coating comprising at least one oxidation catalyst chosen from platinum group metal oxides and at least one dopant for said oxidation catalyst

1. A heating appliance comprising a metal support, at least a portion of which is covered with a self-cleaning coating in contact with the ambient air, said coating comprising at least one oxidation catalyst chosen from platinum group metal oxides and at least one dopant for said oxidation catalyst chosen from rare earth metal oxides, wherein said self-cleaning coating is a bilayer coating comprising: an internal layer at least partially covering the metal support and comprising said dopant, andan external layer in contact with the ambient air and comprising said oxidation catalyst. 2. The appliance as claimed in claim 1, wherein the dopant is chosen from cerium oxides, yttrium oxides and their mixtures. 3. The appliance as claimed in claim 1, wherein the oxidation catalyst is chosen from palladium oxides, platinum oxides and their mixtures. 4. The appliance as claimed in claim 1, wherein said self-cleaning coating is a bilayer coating which is composed of an internal layer of cerium oxide or yttrium oxide and of an external layer of palladium oxide. 5. The appliance as claimed in claim 1, wherein the thickness of the external layer, measured according to the RBS method, is between 10 nm and 500 nm and preferably between 15 nm and 60 nm. 6. The appliance as claimed in claim 1, wherein the thickness of the internal layer, measured according to the RBS method, is between 30 nm and 60 nm. 7. The appliance as claimed in claim 1, wherein it additionally comprises an intermediate protective layer located between the metal support and the internal layer of the self-cleaning coating, said intermediate protective layer being composed of a material chosen from aluminum alloys, enamel and their mixtures, so as to form a support which is catalytically inert as regards the oxidation. 8. The appliance as claimed in claim 7, wherein said intermediate protective layer is made of enamel. 9. The appliance as claimed in claim 1, wherein it is provided in the form of an iron sole plate comprising an ironing surface and in that the self-cleaning coating covers the ironing surface. 10. The appliance as claimed in claim 1, wherein it is provided in the form of a cooking appliance comprising walls capable of coming into contact with contaminants of organic origin, said self-cleaning coating covering these walls. 11. A process for producing a heating appliance comprising a metal support, at least a portion of which is covered with a self-cleaning coating, comprising the following stages: i. the surface of the metal support to be covered is heated to a temperature of 300° C. and 400° C. in an oven or under infrared radiation;ii. a solution of an oxidation catalyst precursor is sprayed over the surface of the metal support to be covered, said oxidation catalyst precursor being chosen from platinum group metal salts, in order to obtain a self-cleaning coating layer,iii. the surface of the metal support covered with the self-cleaning coating layer is baked in an oven or under infrared radiation for a few minutes,wherein the process additionally comprises the doping of said self-cleaning coating layer by a dopant chosen from rare earth metal oxides. 12. The process as claimed in claim 11, wherein the doping and the fixing of said self-cleaning coating layer are carried out during stage ii by addition, to the solution of oxidation catalyst precursor, of a dopant precursor chosen from rare earth metal salts, so as to form a monolayer self-cleaning coating. 13. The process as claimed in claim 11, wherein the doping and the fixing of said self-cleaning coating layer are carried out between stages i and ii as follows: i.1 a solution of a dopant precursor chosen from rare earth metal salts is sprayed over the surface of the metal support to be covered, in order to form an internal coating layer,i.2 the surface of the metal support is again heated to a temperature of between 250° C. and 400° C. in an oven in the infrared radiation sense. 14. The process as claimed in claim 11, wherein the dopant salts or oxidation catalyst salts are acetates, chlorides or nitrates.