CORRECTION DES DÉFAUTS DE SABLAGE D’UN VERRE PAR DÉPOSITION DE COUCHES MINCES DE SILICE ET DE PVB

Abstract

The aim of our work is to correct surface defects caused by the impacts of sand particles on the surface of a glass. The procedure consists to deposit a thin layer of silica by sol-gel technique. For this, soda-lime glass samples were sandblasted with different masses and subsequently thin transparent films were filed. The results show that when the sand mass increases, the number of defects and their size increase also. Optical transmission shows a significant drop. It changes from 91.4% (initial value) to 12.96% for a mass of 200g. Meanwhile, the total roughness increases from 0.65 to 11.75 μm. To correct the sandblasting defects, we synthesized a sol-gel solution based precursors SiO2 (TEOS) and we coated the samples. After drying in an oven heated at 50°C for 30 min, the samples were annealed at 550°C for 1 hour. The average thickness obtained for the deposited layers is very low (380-450) nm. Nevertheless, a significant improvement in the optical transmission has been observed (increase from 12.96 to 42.98%). But this last value is not sufficient. To increase again the thickness, another method is adopted. A polymer (PVB) is dissolved in an adequate solvent (DMF) and the obtained solution is deposited on the SiO2 layers. After drying at 60°C for 24 h, the average thickness obtained in this case is important enough (18.7 μm). This value exceeds the values of the total roughness. Finally, the optical transmission increases significantly up to 88% for Mp = 200 g.