358 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS capiris neonatorum, the sebum leaking scab was no longer observed after four days, and it was nearly cured in eight to ten days. In two cases of facial pimples, no new ones developed after ointment application had begun, and the number of existing pimples decreased until none were observed at all. In two cases of desquamating eczema, scale decreased remarkably after four days, and the scale on the head and face almost vanished. Further, in two cases of eczema erythematosum and contact dermatitis, reddening decreased after three days. In the two ineffective cases, the symptoms were those of serious cases of dermatitis even oral or topical steroid hormone therapy (even in massive doses) was not fully effective, especially if the side effect induced by this hormone is considered. Further, 162 cases of pityriasis simplex capiris and seborrhoea capiris were treated with a lotion containing ethyl alcohol, Tween 80* and 0.02% pyridoxine-3,4-dipalmitate. This lotion was effective in 75% of cases of scaling, in 77% of cases of itching and in 85% of cases of dry dandruff (10). SUMMARY Pyridoxine-3,4-diacylates have been shown to be useful cosmetic ingredients. The diesters of pyridoxine are considered to be more effective than the corresponding triesters since the former's content of the pyridoxine moiety is considerably larger. When heat- and light-stability, fat-solubility, percutaneous ab- sorbability and the effective content of pyridoxine are taken into ac- count, pyridoxine-3,4-dioctanoate emerges as the most suitable deriva- tive for cosmetic purpose. (Received September 14, 1964) REFERENCES (1) Sakuragi, T., and Kummerow, F. A., J. Am. Chem. Soc., 78,839 (1956). (2) Sakuragi, T., and Kummerow, F. A., J. Am. Oil Chemists' Soc., 33, 116 (1956). (3) Sakuragi, T., and Kummerow, F. A., J. Nutrition, 58, 557 (1956). (4) Sakuragi, T., and Kummerow, F. A., Arch. Blochem. Biophys., 63, 32 (1956). (5) Rocheggiani, G., Soap, Perfumery Cosmetics, 34, 547 (1961). (6) Osaka City Institute of Hygiene, reports in files of Nihon Surfactants Industries Co. Ltd. (7) Dept. Dermatology, Osaka Medical College, report in file of Nihon Surfactants Indus- tries Co. Ltd. Kamada, A., Personal communication. Kamada, A., Personal communication. Yasuda, T., Japan. J. Dermatol., 73,487 (1963). * Atlas Chemical Industries, Wilmington, Del. (8) (9) (10)

J. Soc. Cosmetic Chemdsts, 16, 359-363 (1965) A New Procedure for the Preparation of Polyethylene-Mineral Oil Gels PAUL THAU, B.S., and CHARLES FOX, B.A.* Synopsis--A new procedure is described for the preparation of polyethylene-mineral oil gels. This procedure utilizes high shear mixing equipment to maintain a fine dispersion of the polyethylene wax during a critical phasc of the cooling process. The consistencies of gels produced by this procedure are independent of cooling rates. In contrast to existing methods of preparation, this innovation offers advantages in terms of simplified processing and greater formulation flexibility. INTRODUCTION In recent years, polyethylene-mineral oil gels have been employed as vehicles in various dermatologicals (1). The advantages of this type of base over the conventional oleaginous bases are: (a) very little change in consistency over a wide range in temperature, (b) excellent stability at elevated temperatures, (c) improved spreadability (2, 3, 4), (d) release rates of various medicaments which exceeds that from other oleaginous bases (5), and (e) bland and inert characteristics. This type of vehicle is, of course, also useful for the preparation of various cosmetic formulations. However, the previously published procedure (6) for preparing these polyethylene-mineral oil gels has limitations which severely reduce its application to the manufacture of cosmetic preparations. For example, a temperature of 130øC is re- quired to dissolve the high molecular weight (approximately 20,000) polyethylene in mineral oil, and a three hour holding period is said to be required to effect solution. The solution which is then allowed to cool to a temperature just above its cloud point (95øC-100øC) must then * Warner-Lambert Research Institute, Morris Plains, N.J. 07950. 359