Artificially damaged hairs: preparation and application for the study of preventive ingredients.

We have developed a method for preparing artificially damaged hairs, similar to those generally observed in permed hair. Moreover, we have established two models of hair for testing preventive ingredients. A model for scale lift was prepared using alkaline protease digestion following lyophilization. A model for splitting, was prepared by successive extraction of the cortical protein, re-oxidation, and lyophilization. The practical application of these models was confirmed through the evaluation of the preventive effect of a polymer or peptides.