Abstract
Hair components were extracted in order to macroscopically observe the component most involved in formation of permanent waving by thioglycolic acid. In addition, we investigated the influence of treatment with hydrolyzed keratin on permanent wave formation in hair damaged by repeated bleaching treatment. We found that microfibrils is a mandatory component for the desired shape formation of permanent wave by thioglycolic acid, and plays a major role in the shape formation in primary bond than the cuticle and matrix do. Impregnating damaged hair with hydrolyzed keratin resulted in improvement of both permanent waving efficiency and the damage of hair. We hypothesize that hydrolyzed keratin increasing the efficiency of permanent wave formation by maintaining both the shape formation ability of primary bond and the resistance to gravity at the time of secondary bond.
