Development of a Repair Technology for the Inside of Human Hair with Basic Amino Acids

Abstract

The number of women who have trouble with hair protruding from the silhouette increases with aging. When we observed the protruding hair and the normal hair by Transmission Electron Microscope, there were gaps in the Cell Membrane Complex （CMC） of the protruding hair. Based on this result, we focused on CMC constituents and studied the effect of protrusion inhibition. Consequently, L-Histidine （L-His） and L-Arginine （L-Arg） had high effects, and we confirmed that the amount of these amino acids in the female hair decreased with aging. Then we developed a hair conditioner which could highly inhibit protrusion, by penetrating and retaining both amino acids inside the hair. It was found that Phytosteryl／Octyldodecyl Lauroyl Glutamate retained the amino acids inside the hair. Moreover, L-His and L-Arg, which were added to the conditioner formulations, were confirmed by stable isotope imaging to have penetrated inside the hair. According to this study, the hair-repair effect of L-His and L-Arg was obtained.