Hydrophobic materials made of silica as a coating for glasses are very attractive. The synthesis (SiO 2 ) from rice husk ash was successfully carried out using the sol-gel method. hydrophobic composition is with four variations silica, consisting 0.5, 1.0, 1.5, 2.0 g and polydimethylsiloxane (PDMS) keep constant in 20 g. raw material first characterized by X-ray Fluorescence (XRF) to investigat...