LANOLIN DERIVATIVES IN PRESSURIZED FORMULATIONS II 37 Crystal formation occurred with water soluble wool alcohols "oe0" (x) in the paraffin/alcohol system (N). Water (Systems O-Q Table H) The solvent power of the two systems incorporating halocarbon pro- pel!ants (O,P) has decreased marginally, while that of the butane system (Q) has increased to a similar extent. In general there have been only minor changes in solubility during the test period. Crystal formation occurred with wool alcohols, O.P. (ii) in both halocarbon propellant systems (O,P). Storage for 6 weeks at OøC The solvent power of all seven propel!ant systems decreased (Table II). In all propellant systems there is a marked decrease in the solubility of anhydrous lanolin, B.P. (i), and a moderate decrease in the solubility of liquid lanolin "R.I.C.2" (vii). With the other eight products, the decrease in solubility is almost negligible when compared with that obtained after six weeks' storage at 20øC. Agglomeration of separated matter is more prevalent. Storage for 6 weeks at OøC, followed by storage for 24 hours at 20øC In general, the solubilities are similar to those noted after storage for 6 weeks at 20øC, with the exception of liquid lanolin "R.I.C.2" (vii) in the presence of propel!ant 114 systems (L) and (P). Spray results (Table VI) Spray failure occurred only in systems incorporating propellant 114. (L),(P), and was generally caused by agglomerated particles jamming in the valve housing. Anhydrous lanolin, B.P. (i), liquid lanolin "A.C.E." (iii), liquid lanolin 'TS.O." (vi), liquid lanolin "L.I.N." (viii) did not cause valve blockage in any of the propellant systems tested. Spray characteristics Table III indicates that quick-breaking foams were obtained with wool alcohols, B.P. (ii), and alcohol soluble lanolin (iv) in propellant 114/IMS/ water (P), and in butane/IMS/water (Q) systems. Also with water soluble alcohols "20" (x) in the propellant 12/paraffin system (K). With wool alcohols, B.P. (ii) a stable foam on impingement was obtainable. Effect of shaking on separated matter All containers were shaken for • minute and the time taken for the

38 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS settling of the redispersed matter was noted. The results are detailed in Table VI. CONCLUSIONS By adding the numbers in Tables I and L/ both horizontally and vertically, a total for each individual lanolin product in all propellant systems is obtained, together with a total for each individual propellant system containing all lanolin products. The lower the total, the better the solubility or solvent power. Liquid lanolin "50 Super" (v) was found to be the most soluble product, whereas anhydrous lanolin, B.P. (i), wool alcohols, B.P. (ii), alcohol soluble lanolin (iv), and water soluble lanolin "75" (ix) are almost identically least soluble. The solubility of anhydrous lanolin, B.P. (i), wool alcohols, B.P. (ii), liquid lanolin "A.C.E." (iii), and water soluble lanolin "75" (ix) in the various propellant systems decreases on storage, whereas that of liquid lanolin "50 Super" (v) increases during the storage period. As might be expected, only water soluble lanolin "75" (ix), and water soluble wool alcohols "20" (x) are moderately soluble in the aqueous systems (O-Q), but the limited extent of this is somewhat disappointing. Storage at 0øC materially affects the solubility characteristics of anhydrous lanolin B.P. (i), and of liquid lanolin "R.I.C.2" (vii). Propellants 11/12/liquid paraffin/IMS (N) was found to be not only the best propellant system in respect of solvent power, but also far superior to all the other six propellant systems, the solvent powers of which decreased on storage, as will be seen from Tables I and !I, The results obtained with the propellant 114/IMS/water system (P) should be treated with a certain amount of reserve because of the irre- versible separation into two liquid phases recorded after 6 weeks' storage at OøC (Table V). (Received: 7`1th June 796,t) REFERENCE (1) Herzka, A. J. Soc. Cosmetic Chemists 14 331 (1963).