Studies for analyzing the restricted ingredients such as 2-(2'-hydroxy-5'-methylphenyl)-benzotriazole

2-(2'-hydroxy-5'-methylphenyl)-benzotriazole (HMB) is nominated as the restricted ingredients in cosmetics in Japanese Pharmaceutical Affairs Act. So the analytical method for HMB was investigated by HPLC. After dissolving HMB in cream or oil with tetrahydrofuran and making the constant volume with methanol, the test solution was prepared. Twenty micro-liter of the test solution was determined by HPLC by using CAPCELL PAK C18 column, the mixture of methanol and water (17:3) as mobile phase, the detection wavelength at 306 nm. The concentrations of 10 to 80 micrograms/ml HMB gave the linear relationship between the concentrations and the peak areas. In creams and oil 0.1% and 1% HMB were sufficiently determined by the established method.