Method for the production of a thin glassy coating on substrates in order to reduce gas permeation

摘要

Disclosed is a process for producing a glasslike, transparent coating on a substrate, by coating the substrate with a solution comprising: a) a polysilazane of the formula -(SiR'R''-NR''')n-, where R', R'', R''' are each chosen from hydrogen, alkyl, aryl, vinyl or (trialkoxysilyl)alkyl, where n is an integer such that the polysilazane has a number-average molecular weight of from 150 to 150 000 g/mol; and b) a catalyst in an organic solvent, subsequently removing the solvent by evaporation to leave a polysilazane layer having a layer thickness of 0.05-3.0 micrometers on the substrate, and irradiating the polysilazane layer with VUV radiation with wavelength fractions 230 nm and UV radiation with wavelength fractions between 230 and 300 nm in a steam-containing atmosphere in the presence of oxygen, active oxygen and optionally nitrogen.