Corrosion inhibition of alkali metal-silicate glass by treatment in a low temperature plasma

A plasma treatment has been included in the cleaning and drying stage of the manufacturing process of precision optical glas parts. By this treatment the optical properties remain unchanged or are even slightly improved compared to the former teatment with chlorofluorocarbons. The corrosion of the plasma treated alkali metal-silicate glasses that have been studied is inhibited and a much better corrosion resistance is obtained. In previous work it was shown, that alkali elements can be removed from float glass surfaces. It also could be shown, that removalof alkali ions corresponds for this type of glas to improved corrosion resistance. In the present work, corrosion resistance of optical glasses was improved without significant removal of alkali elements.