188 JOURNAL OF COSMETIC SCIENCE ASIAN AND CAUCASIAN HAIR- DIFFERENCES OF INFLUENCE FOR THE FORMULATION? J. Kahre•., P. Bush •, B. Salka 2, N. Totani 3 and W. Poly 3 •Henkel KGaA, D-40191 Diisseldorf Germany 2 Henkel Corp., Ambler, PA 19002 3Henkel Japan Ltd., Tokyo, Japan Introduction: Hair is undoubtedly one of the most important features of people in all cultures. For the past several centuries hair has played an important role. Style, length and color changes are influenced by fashion trends. The hair often allows for feelings of health and beauty, and thus its influence is of great importance. Therefore hair has been studied greatly as cited in numerous publications.Three major types of hair are known: african, asian and caucasian hair. The differences of the hair types are related to the diameter, geometry and other physical parameters. Closely related to these parameters are the biophysical factors, tensile strength and combing forces, which might be influenced by cosmetic formulations that are applied to hair. We examined asian and caucasian hair and applied shampoo and conditioner formulations in order to study their effects. Experimental: Bioph¾sical measurements: Asian and caucasian hair from Alkinco New York was used. Tensfie strength and combing forces were measured using a robotic system as described in the literature (1/2). Results: A - Combing Work and Tensile Strength The differences in the morphology (area, thickness, half axes) influence physical properties (see figure I and 2). B - Application of different shampoos The addition of protein hydrolysates increases the tensile strength of damaged hair of both types. A special shampoo for fine hair (94/145/11) shows differences in the objectively measured efficacy. It is best applicable on caucasian hair for which it was developed. It seems that a ,,world formulation" is possible by adjusting the concentration of quaternary polymers (see figure 3, 4 and 5). C - After Hair Treatments The tested formulations have the same efficacy on both hair types. The addition of emol- lients shows more of a increase on asian hair than on caucasian hair (see figure 6 and 7). Conclusion: Due to the differences in the morphology we found differences in the biophysical behavi- our of asian and caucasian hair. We also found differences in the efficacy of shampoo and conditioners. Therefore it is better to develop different products for different hair types. Literature 1) Busch, P., Thiele, K., Fischer, D. Seifen, Ole, Fette, Wachse 108 305-309 (1989) 2) Busch, P. •rztliche Kosrnetologie 19 270-315, 1989

PREPRINTS OF THE 1998 ANNUAL SCIENTIFIC SEMINAR 189 •!1/Differences of Asian and Caucasian Hair •./• and Wet Tensile $b'en•th of SI• •m Differences of Asian and Caucasian Hair "1 [" -.. . .. Influence of Shampoos •_../- Wet Tm•lle •tmngth of Perreed Hair Al•llcatlon of P•oteln Hydroly•t• and Smf•ctant• ß Influence of Shampoos. •.,,./* Dry and Wet Combing Work . Influence of Shampoos •.,/o Formulations - Dry and Wet Combing Work .,lh . After Hair Treatments ,•.,/o Dry and Wet Combing Application of Conditionera . .• •. .,' • c•uc.•.i•m After Hair Treatments Wet Combing Work I Emollients in ConditJonem •: , .:, •.',• ß .:• ) .... ] iiiiiiiiiiiiiiii ii