Glass surfaces, including those of automotive glazing, show insufficient scratch resistance. In order to improve this, a sol-gel process has been developed by means of which scratch resistant and transparent corundum coatings may be deposited on glass suraces. Coatings which were produced by using commercial boehmite (AlOOH) dispersions could also be completely transformed. Coatings produced by an alkoxide-gel process from aluminium butoxide were dense at a thickness of maximal 100nm and adhered very well to the glass surface which had been slightly roughened by HF etching. A scratch test with a quartz grain showed that the damage of the glass surfaces coated in this way was less than 2% compared to that of uncoated surfaces. Transmission of these glasses was about 90% in the visible wavelength range.
