PROCESS FOR PRODUCING A PROTECTING COATING ON A SURFACE OF A GLASS OR CERAMIC ARTICLE

摘要

The invention relates to a process for producing a protecting coating on a surface of a glass or ceramic article, said coating having an improved resistance to caustic wash treatments. In carrying out the inventive process a stream of an oxygeneous carrier gas containing a thermodecomposable precursor of tin oxide (SnO2) and a thermodecomposable precursor of silicon oxide (SiO2) in a molar ratio of the former precursor to the latter between 0.6 and 3.0, said precursors being present in evaporated form, and further containing water vapor in an amount of at least 1 mole per 100 moles of carrier gas, is uniformly impinged onto the surface to be coated, said surface having a temperature which is above the decomposition temperatures of said precursors and amounts to at least 550 DEG C, to deposit a mixed oxide protecting coating comprising tin oxide and silicon oxide, and the deposition is continued until a coating thickness of between 240 and 1,500 ANGSTROM is obtained.