Takashige Yoneda

Mechanical durability of water repellent glass

Water repellent films were formed on various glass substrates at room temperature using polyfluoroalkyl isocyanate silane as a starting material. Initial water repellency and mechanical durability of the water repellent film were examined. It was found that the water repellency and the mechanical durability were dependent on the surface state and the surface roughness of the glass substrate. The dependence of the mechanical durability on the surface state of the glass substrates is explained by the density of the absorbed water repellent molecules bonded to silanol groups on the surface of glass substrates. Roughed surface structure of the glass substrate prevented the water repellent film from abrasion and improved durability of it against abrasion. Silica film formed on the substrate using TMOS and the silica fine particles effectively improved the durability of the water repellent film. The durability mechanisms are described in detail based on the results of XPS, IR, Static SIMS and AFM analysis.