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J. Soc. Cosmet. Chem. 25, 325-337 (1974) ¸ 1974 Society of Cosmetic Chemists of Great Britain The behaviour of perfumery ingredients in products J. W. K. BURRELL* Presented at the 2nd Joint Perfumery Symposium organized by the British Society of Perfumers and the Society of Cosmetic Chemists of Great Britain at Eastbourne on 7-9th May 1973 Synopsis-•A new technique involving the GLC ANALYSIS of PERFUMERY INGREDIENTS directly from product bases has been developed. This technique has been used to study how materials behave in SOAPS and laundry powders after storage under various conditions. INTRODUCTION Perfumers and cosmetic chemists have for some time been interested in predicting how perfumes will behave in the various bases into which they are to be incorporated. Until now, the perfumer has had to resort to many hours of tedious trial and error to ensure a final pleasing effect and even then he could not be certain that the effect will hold constant over months of storage under possibly adverse conditions. Apart from simple frustration and tedium, this situation presents problems of economics. It is of little value incorporating relatively ex- pensive ingredients in a product if they contribute nothing to the odour over time because of incompatibility with the base or because they are lost by chemical reaction or evaporation. It therefore became imperative that reliable objective methods should be developed to study these problems of behaviour in greater detail. *Proprietary Perfumes Ltd, Ashford, Kent. 325