Optical behavior of spirooxazine incorporated vinyl functional silicates thin film under UV irradiation

Photochromic film of Spirooxazine-incorporated organosillicates material was prepared by sol-gel method and deposited on quartz substrate. The film was examined through the variation of UV irradiation power and exposure time for optical behavior characterizations. Investigations have been carried out by UV-Vis spectrophotometry and spectroscopic reflectometry. It was found that the absorption spectra of film at the region of 230-250nm were decreased indicating the reduction of C=C to C-C bond with increased of power and exposure time of UV irradiation were increased. On the other hand, we observed that the photo transformation absorption peak was also change at the region of 610nm to 620nm when different duration of UV irradiation applied. In addition, this UV curing process also increased the refractive index of film since the structures become compacted due to reduction of pore size volume in the system. Thus it will limit the film ability to performed photo transformation which will contribute to the reduction of film coloration upon UV irradiation. It is concluded that consideration of power and duration of UV irradiation is significant for designing the function of photochromic film in led their successful use in various applications.