LIGHT SCATTERING IN HAIR CUTICLES 365 a) Figure 18. Mean total number of cuticle layers before and after cleansing/combing cycle. In order to evaluate the protection effect of the MA/BOE against damage to the cuticle, a decrease in the number of the cells was counted after 150 times through the hair care cycle: shampooing/rinsing/blow-drying with combing. Figure 18 shows the comparison of the mean total number of cuticle layers before and after hair care cycles. The lack of cuticle layers was confirmed in fibers both with and without MA/BOE treatment during the cycles, but the fracture of cuticle layers was suppressed by MA/BOE treatment. It can be said, therefore, that MA/BOE treatment is effective both for developing hair shine and for protection from cuticle damage by the blow-drying/combing process. ACKNOWLEDGMENTS The authors are grateful to Dr. Tatsushi Wakisaka, Mr. Yoshikazu Ohtsuka, and Ms. Yoshiko Chikawa of the Analytical Research Center, Kao Corporation, for their technical assistance and helpful discussions. The authors also thank Mr. Itomi Homma, Director of Hair-Care Laboratories, and Dr. Koichi Nakamura of Hair-Care Laboratories, Kao Corporation, for helpful discussions and guidance. REFERENCES (1) S. Nagase, S. Shibuichi, M. Ohshika, M. Okamoto, Y. Masukawa, A. Mamada, and N. Satoh, Light- scattering control at medulla enhances human hair shine, Proceedings of the 21st IFSCC International Congress 2000, Berlin, 153-159 (2000), and references therein. (2) S. Nagase, S. Shibuichi, K. Ando, E. Kariya, M. Okamoto, A. Mamada, and N. Satoh, Structure factors of hair fiber influencing beautiful appearance of hair, Proceedings of the 21st IFSCC International Congress 2000, Berlin (2000). (3) M. Okamoto, A. Mamada, R. Yakawa, S. Inoue, S. Nagase, S. Shibuichi, and N. Satoh, Hole generation mechanisms in hair medulla and its repairing technique, Proceedings of the 21st IFSCC International Congress 2000, Berlin (2000). (4) S. Nagase, S. Shibuichi, K. Ando, E. Kariya, and N. Satoh, Influence of internal structures of hair fiber

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