726 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Society of Cosmetic Chemists Journal Advertising takes your message straight to the Chemists of the Cosmetic Industry For information address: Editorial Assistant Society of Cosmetic Chemists 2758 Pine Hill Drive Birmingham, Michigan 48008

•. Soc. Cosmetic Chemists, I5, 7:27-743 (1963) THE USE OF CONSTANT-TEMPERATURE DILATOMETRY FOR THE STUDY OF SURFACE ANOMALIES OF FATTY SUBSTANCES By E. MAHLER, ING. CI-II:M.* Presented )•une 22-26, I964, Third Congress International Federation of Societies of Cosmetic Chemists, New York City ABSTRACT Surface defects of suppositories, lipsticks, eyebrow pencils, etc. may be due to one of the following: (1) Formation of crystals due to the presence of a foreign substance (2) Contamination by molds, fungi, etc. (3) Excrescence of solid fatty substances (4) Formation of wrinkles and (5) Exudation of liquid substances. The appearance of these surface defects is demonstrated photographically. A method for constant temperature dilatometry is described, and experimental data obtained by this procedure permit further insight into the causes of some of these surface defects. Techniques for the prevention of formation of surface defects are discussed. INTRODUCTION Recent experimental studies of several triglyceride bases used in the manufacture of lipsticks, eyebrow pencils and suppositories permitted ob- servations of numerous changes, such as bloom, etc., on the surface of these preparations. In order to reduce the incidence of these defects or to elim- inate them entirely, the conditions of appearance of these anomalies and their nature were studied. A variety of classical preparations, notably cosmetic sticks, pencils and pharmaceutical suppositories, were investigated. These preparations have one common feature: they consist largely of fatty acid esters, spe- cifically glycerides, with melting points ranging from +30 to d-52øC. In addition, they may contain emulsified or suspended liquid or powdered components. In view of the complexity of the formulas and multiplicity * Sociat• Gattefoss• SFPA, Lyon 3e, France. 727