188 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS 1.0 0.6 E 0.4 0.2 - wt% ß Liquid paraffin 28 . ß i•-G+SCS 2 ß Glyceryl monostearate 2 ß Water 68 I I I I 0 0.2 0.4 0.6 0.8 1.0 I•-G/( jS-G + SCS ) (wt. rat io) o C Figure 12. Effect of [•-G on emulsion stability. Centrifugation: 3000 rpm, 30 , 15 min. oils in this experiment ranged from 10.2 to 17.0. Stability of the emulsions observed after ten days storage at room temperature demonstrated that [3-G has enough emulsi- fying ability for various oils lying over a wide range of HLB values. Furthermore, the effect of [3-G on emulsion stability was investigated by partially replacing •3-G with SCS as shown in Figure 12. Stability of the emulsion was judged by volume ratio of residual emulsified layer after centrifugation. It is obvious that the addition of gives rise to prominent stabilization of emulsions probably due to gel formation. ACKNOWLEDGEMENTS We wish to thank Dr. S. Yamazaki and Dr. A. Okubo, Department of Agricultural Chemistry, Faculty of Agriculture, University of Tokyo, for the measurement of NMR spectra and critical discussion. We are indebted to Dr. H. Yoshioka, Shizuoka College of Pharmacy, for valuable advice. Thanks are also due to Mr. H. Futagoishi, emeritus

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