Abstract
In this paper, the stain resistance of external finishing materials containing titanium dioxide that has the effect of photocatalyst was investigated. Exposure tests to compare the stain resistance of photocatalyst coating materials were performed in Yokohama. The changes in difference of luminosity was observed for 1 years. It was found that photocatalyst coating materials showed the best stain resistance among coating materials, but there were problems of weather resistance and with recoating. Therefore attention is indispensable when adopting photocatalyst coating materials.
