Studying the mechanisms of titanium dioxide as ultraviolet-blocking additive for films and fabrics by an improved scheme

Titanium dioxide (TiO2) has good ultraviolet (UV)-blocking power and is very attractive in practical applications because of such advantages as nontoxicity, chemical stability at high temperature, and permanent stability under UV exposure, for example. Development of nanoscience and -technology provides new ways for better treatment for UV-resistant films and fabrics using TiO2, However, the exact mechanisms of TiO2 as a UV-blocking additive are still not very clear, and researchers hold different views on this issue. The aim of this investigation was to study systematically the mechanisms of TiO2 as a UV-blocking additive for films and fabrics. To achieve this goal, the conventional scheme describing light interactions with fabrics was revised based on more recent progress in optical theory, and special experiments and analytic methods were used in the investigation. Several effects attributed to the nanoscale additives were identified. Moreover, detailed analyses based on the results yielded a few important suggestions useful in developing or improving both inorganic UV-blocking agents and the UV-protective films and textiles. (C) 2004 Wiley Periodicals, Inc.