J. Cosmet. Sci., 64, 19–33 (January/February 2013) 19 Alignment control and softness creation in hair with glycylglycine STEVEN BREAKSPEAR, MASAKI FUKUHARA, TAKASHI ITOU, YUJI HIRANO, MASAYOSHI NOJIRI, AKIRA KIYOMINE, and SHIGETO INOUE, Beauty Research Center, Kao Corporation, 2-1-3 Bunka, Sumida-ku, Tokyo 131-8501 (S.B., M.F., T.I., Y.H., M.N., A.K.), and Analytical Science Research Laboratories, Kao Corporation, 1334 Minato, Wakayama-shi, Wakayama 640-0112 (S.I.), Japan. Accepted for publication May 9, 2012. Synopsis Thick and coarse hair, as typically found among the Japanese population, frequently lacks softness that con- sumers are acutely aware of. Such poor feeling is accentuated by daily grooming, weathering, and chemical treatments, in particular, which can cause changes in the hair shape and the creation of frizzy or irregularly shaped hair. Existing technologies to improve the soft feel of hair, though effective, usually concentrate on the surface of the fi ber and often leave the hair feeling either overconditioned or sometimes even sticky from product buildup. Hair softness is said to be governed by a number of factors, but primarily hair diameter and surface condition. In this study, we have also identifi ed hair alignment as playing a critical role in hair softness. In addition, by studying how Japanese women perceive hair softness when touching their hair, we have identifi ed that the strain on the hair fi ber associated with these manipulations is far smaller than previously considered. With these factors in mind, we have studied the mechanisms behind a new softening technology containing gly- cylglycine (GG). It has been found that treatment with GG can give a tangible feeling of hair softness by dramatically improving alignment in unruly hair and by lowering the modulus of the fi ber. Moreover, using the atomic force microscope, it has been revealed that the properties of the cell membrane complex of the hair cortex may be modifi ed after GG treatment the role of this additive in modifying the internal properties of the hair to create softness will thus be discussed. INTRODUCTION Little information has been published about the softness of human hair fi bers. Instead, research has focused on a close cousin to the human hair fi ber: wool. Stevens (1) defi nes softness purely as (i) having a smooth surface or fi ne texture and (ii) yielding to pressure or easily deformed. Both of these characteristics may equally apply to a bulk of fi bers or This paper was presented at the 16th International Hair Science Symposium (HairS’09), September 9–11, 2009, Weimar, Germany.