Study on the sorption of calcium ion to human hair

• Published in: Journal of Society of Cosmetic Chemists of Japan Vol. 22; no. 2; pp. 88 - 95
• Main Authors: Uzu, Atsushi, Watanabe, Taichi, Ogino, Hidekazu, Hirota, Hajime
• Format: Journal Article
• Language: English
• Published: The Society of Cosmetic Chemists of Japan 1988
• ISSN: 0387-5253; 1884-4146
• DOI: 10.5107/sccj.22.88

The effects of increased calcium content in hair caused by coldwaving on the mechanical nature of the hair were studied. It was revealed that the heavy sorption of calcium ion to the hair made its rigidity increased. The sorption behavior of calcium ion to the hair was also investigated. Namely, the distribution of the ion in the hair was examined by electron probe microanalyzer. The influences of pH of the bathing solution and the chemical modification of the hair on the sorption were studied. The results indicated that calcium ion penetrated into the hair cortex, as well as adsorbed on the hair surface, and that the sorbing site was mainly the dissociated carboxyl group of the hair keratine. Furthermore, to elucidate the cause of the high calcium uptake of the permed hair, the sorption isotherm and the sorption rate were investigated. The both results obtained implied that the high calcium uptake of the permed hair was derived from the increased difussion coefficient of the ion into the hair, and from the increase of the dissociated carboxyl group.