Abstract: An insulator with a molding made of ceramic and a hydrophobic coating applied to the surface of the molding is disclosed, the hydrophobic coating comprising a plasma polymer having been applied directly to the ceramic. The previously customary glaze on the surface of the ceramic is replaced by the plasma polymer. Such an insulator has high long-term stability with regard to its electrical insulating capability. It is possible to dispense with complicated shaping of the molding to increase the leakage path over the surface of the ceramic and with the application of a glaze, which means a considerable cost saving.

Abstract: An electrical insulator is produced by coating a molded part of the insulator with a hydrophobic plasma-polymer coating. The plasma-polymer coating is produced by igniting a plasma in a non-polar working gas or a working gas having non-polar groups at a working pressure of between 0.001 Pa (1·10−5 mbar) and 50 Pa (5·10−1 mbar). The electrical power input per chamber volume lies between 0.5 and 5 kW/m3, the gas flow per chamber volume lies between 10 and 1000 sccm/m3. A durable, hard and hydrophobic plasma-polymer coating is created, the quality of which is independent of the material of the molded part.

Abstract: A process is described for producing porcelain, in particular high-strength porcelain and a ceramic insulator. To produce the porcelain, calcined bauxite is used instead of alumina. The simultaneous addition of clay and kaolin, in each case containing more than 5% by weight of foreign metal oxide inclusions, results in a porcelain which, compared to an alumina porcelain of the same mechanical strength, can be produced at significantly lower cost. The porcelain is suitable in particular for applications for highly mechanically loaded components used in electrical insulation.

Abstract: A process is described for producing porcelain, in particular high-strength porcelain and a ceramic insulator. To produce the porcelain, calcined bauxite is used instead of alumina. The simultaneous addition of clay and kaolin, in each case containing more than 5% by weight of foreign metal oxide inclusions, results in a porcelain which, compared to an alumina porcelain of the same mechanical strength, can be produced at significantly lower cost. The porcelain is suitable in particular for applications for highly mechanically loaded components used in electrical insulation.

Abstract: The present invention relates to surface-modified insulators obtained by coating an insulator body with a preparation containing at least one organofluorine-functional silane and/or siloxane, at least one mineral acid and at least one metal salt of aluminum(III), tin(II), tin(IV), iron(III) or titanium(III) as catalyst, to a process for their preparation and to the use of the preparation for coating insulators.

Abstract: An insulator with a molding made of ceramic and a hydrophobic coating applied to the surface of the molding is disclosed, the hydrophobic coating comprising a plasma polymer having been applied directly to the ceramic. The previously customary glaze on the surface of the ceramic is replaced by the plasma polymer. Such an insulator has high long-term stability with regard to its electrical insulating capability. It is possible to dispense with complicated shaping of the molding to increase the leakage path over the surface of the ceramic and with the application of a glaze, which means a considerable cost saving.

Abstract: An electrical insulator is produced by coating a molded part of the insulator with a hydrophobic plasma-polymer coating. The plasma-polymer coating is produced by igniting a plasma in a non-polar working gas or a working gas having non-polar groups at a working pressure of between 0.001 Pa (1·10−5 mbar) and 50 Pa (5·10−1 mbar). The electrical power input per chamber volume lies between 0.5 and 5 kW/m3, the gas flow per chamber volume lies between 10 and 1000 sccm/m3. A durable, hard and hydrophobic plasma-polymer coating is created, the quality of which is independent of the material of the molded part.

Abstract: The present invention relates to a process for the production of polycrystalline silicon mouldings substantially free of low lifetime edge regions and the use of these mouldings.