Abstract

Exposure to UV light, i.e., UV-A (320-400 nm) or UV-B (290-320 nm) radiation, can cause skin cancer. Titanium dioxide (TiO2) effectively disperses UV light. Therefore, it is used as a physical UV filter in many UV light blockers. Usually, the TiO2 content in commercialized UV blockers is 25 % at most. To block UV-B, a chemical UV blocker, octyl-methoxy cinnamate (OMC) is used. OMC is commonly used in combination with TiO2. In this study, TiO2 and OMC were mixed in different proportions to produce UV blockers with different compositions. Also the changes in the sun protection factor (SPF) based on the composition and TiO2 particle sizes were investigated. In order to analyze the TiO2 particle size, dynamic light scattering (DLS) and asymmetrical flow field-flow fractionation (AsFlFFF) were used. The results showed that the SPF was influenced by the proportion of TiO2 and OMC, where the proportion of TiO2 induced a more significant influence. In addition, changes in the TiO2 particle size based on the proportion of OMC were observed.