F2 laser formation of SiO2 protective layer onto polycarbonate for lightweight vehicle window

Silicone-coated polycarbonate (PC) through an acrylic primer was photochemically modified into silica (SiO2) by 157 nm F2 laser. The photomodified surface showed high scratch resistance comparable to the case in a bulk silica. Corresponding to the conversion of silicone into silica on PC, the photomodified surface was found to be shrunk, measured by a surface profilometer. For instance, the coated silicone on PC reduced the thickness of approximately 15 % when the F2 laser modified silicone into silica 0.59 μin thickness. An excess irradiation of F2 laser for the photochemical modification induced the degradation of acrylic primer underneath silicone.