An Evaluation Method for Shampoos Using Human Hair Keratin Film

The study evaluated the use of keratin film, derived from human hair protein, as a substitute for hair in assessing damage caused by factors like UV rays and heat. The research tested the film's resistance to commercial shampoos and conditioners and its utility in analyzing friction and adsorption. Results showed that the keratin film's mass and microstructure were largely unaffected by these treatments. Using a friction tester, the film's mean friction coefficient (MIU) was significantly higher than that of hair bundles, but it remained stable even after 20 repeated measurements in both dry and wet conditions. Notably, the MIU decreased significantly when treated with conditioners alone or in combination with shampoos, varying by product. Energy-dispersive X-ray analysis revealed that films treated with silicone-containing products had uniformly adsorbed silicon. These findings suggested that keratin film could effectively measure and evaluate hair texture and adsorption properties.