1. Product Development Department POLA Chemical Industries, Inc. 560 Kashio‐cho, Totsuka‐ku Yokohama 244‐0812 Japan
2. Frontier Research Center POLA Chemical Industries, Inc. 560 Kashio‐cho, Totsuka‐ku Yokohama 244‐0812 Japan
3. Department of Dermatology Kizawa Memorial Hospital 590 Shimokobi, Kobi Minokamo, Gifu 505‐8503 Japan