2O8 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS phase equilibria of the system under investigation, the formulator will be able to undertake a more rational and fundamental approach to de- signing a particular product to perform a particular task. (Received May 19, 1967) REFERENCES (1) Dervichian, D. G., Solubilization by association, 2nd International Congress on Surface Activity, Vol. 1, Butterworths, London, 1957, pp. 327-333. (2) Mulley, B. A., Solubility in systems containing surface active agents, in Bean, H. S., et al., Advances in ]harmaceutical Sciences, Vol. 1, Academic Press, London, 1964, pp. 140-151. (3) Lawrence, A. S.C., Internal solubility in soap micelies, Trans. Faraday Soc., 33, 815- 820 (1937). (4) Haydon, D. A., and Taylor, F. H., Adsorption at the oil-water interface and the calcula- tion of electrical potentials in the aqueous surface phase. I., ]hil. Trans. Royal Soc. London, A252• 225-248 (1960). (8) Molyneux, P., Rhodes, C. T., and Swarbrick, J., Thermodynamics of micellization of N-alkyl betaines, Trans. Faraday Soc., 61• 1043-1052 (1965). (6) Boon, P. F. G., Coles, C. L. J., and Tait, M., The influence of the variations in solubilis- ing properties of polysorbate 80 on the vitamin A palmirate: polysorbate 80: glycerol: water system, J. ]harm. ]harmacol., 1•1• 200-204T (1961). (7) Burr, B. W., An approach to emulsion formulation, J. Soc. Cosmetic Chemists, 16• 465-477 (1965). (8) Hyde, A. J., Langbridge, D. M., and Lawrence, A. S.C., Soap q- water q- amphiphile systems, Discussions Faraday Soc., 18• 239-258 (1954). (9) Winsor, P. A., Solvent ]roperties of Amphiphilic Compounds, Butterworths, London, 1954, p. 34. (10) Osipow, L. I., Surface Chemistry, Reinhold, New York, N.Y., 1962, pp. 328-337. (11) Beeher, P., Emulsions: Theory and ]ractice, 2nd ed., Reinhold, New York, N.Y., 1968, pp. 169-208. (12) Beeher, P., The effect of the nature of the emulsifying agent on emulsion inversion, J. Soc. Cosmetic Chemists, 9• 141-148 (1958). (13) Salisbury, R., Leuallen, E. E., and Charkin, L. T., The effect of phase volume ratio on emulsion type, J. Am. ]harm. Assoc., Sci. Ed., 43• 117-119 (1954). (14) Riegelman, S., The effect of surfactants on drug stability, Ibid., 49• 339-343 (1960). (15) Anderson, R. A., and Slxde, A. H., The effect of polyoxyethylene compounds on the hydrolysis of chlorbutanol, J. Pharm. ]harmacol., 18• 640-648 (1966). {16) Mitchell, A. G., and Brown, K. F., The interaction of benzoic acid and chloroxylenol with cetomacrogol, Ibid., 18, 115-125 (1966). ,(17) Anderson, R. A., and Morgan, K. J., Effect of solubilisation on the antibacterial activity of hexachlorophane, Ibid., 18,449-456 (1966). (18) Mitchell, A. G., The hydrolysis of propyl benzoate in aqueous solutions of cetomacrogol, Ibid., 15• 761-765 (1963) The hydrolysis of propyl benzoate in aqueous solutions of surface-active agents, Ibid., 16• 43-48 (1964). (19) Swarbrick, J., and Carless, J. E., Phase equilibria in some betaine-benzaldehyde-water systems, Ibid., 15, 507-517 (1963). (20) Swarbrick, J., and Carless, J. E., Oxidation of benzaldehyde in some single phase betaine- benzaldehyde-water systems, Ibid., 16• 596-602 (1964) Oxidation of benzaldehyde in some multiphase betaine-benzaldehyde-water systems, Ibid., 16,670-676 (1964).

PHASE EQUILIBRIUM DIAGRAMS 209 (21) (22) (23) (24) (25) (26) (27) (28) (29) (30) (31) Mitchell, A. G., and Wan, L. S.C., Oxidation of aldehydes solubilized in nonionic sur- factants, J. Pharm. Sci., 54,699-704 (1965). Swatbrick, J., and Rhodes, C. T., Auto-oxidation of linoleic acid in micellar solution, Ibid., 54,903-906 (1965). Nixon, J. R., and Chawla, B. P.S., Viscosity and stability relations of the system as- eorbie aeid:water:polysorbate 20, J. Pharm. Pharmacol., 17, 558-565 (1965). Lewis, J. M., Coylan, S. Q., and Messina, A., Further observations on the absorption of vitamin A. Influence of the particle size of the vehicle on the absorption of vitamin A, Pediatrics, 5,425-436 (1950). Levy, G., and Reuning, R. H., Effect of complex formation on drug absorption, J. Pharm. Sci., 53, 1471-1475 (1964). Vamada, H., and Vamame, to, R., Biopharmaeeutical studies on factors affecting rate of absorption of drugs. I., Chem. Pharm. Bull. (Tokyo), 13, 1279-1284 (1965). Vamada, H., Iehihashi, T., Kogishi, F., and Vama•noto, R., Biopharmaeeutical studies on factors affecting rate of absorption of drugs. II., Ibid., 14, 786-788 (1966). Sjoblem, L., Studies on the solubilization of oestrone and its percutaneous absorption in mice, Acta Acad. Aboensis, Math. Phys., 20, 75-164 (1956). Bean, H. S., and Berry, H., The bactericidal activity of phenols in aqueous solutions of soap. Part I, J. Pharm. Pharmacol., 2, 484-490 (1950) Part II, Ibid., 3, 639-655 (1951). Swatbrick, J., Solubilized systems in pharmacy, J. Pharm. Sci., 54, 1229-1237 (1965). Wedderburn, D. L., Preservation of Emulsions Against Microbial Attack, in Bean, H. S., et al., Advances in Pharmaceutical Sciences, Vol. 1, Academic Press, London, 1964, pp. 195-268.