HAIR PHOTOCHEMISTRY 99 (3) G. Reese and N. Maak, Die Bestiindigkeit von Haafarben unter dem Einflu[3 von Sonne, Wasser, Salz, ß alrztl. Kosmetol., 12, 373-379 (1982). (4) E. Tolgyesi, Weathering of hair, Cosmet. Toiletr., 98, 29-33 (1983). (5) M. Tatsuda, M. Uemura, K. Torii, and M. Matsuoka, Studies on hair damage and demelanization by ultra violet light, J. Soc. Cosmet. Chem. Japan., 21, 43-49 (1987). (6) R. Crippa, V. Horak, G. Prota, P. Svoronos, and L. Wolfram, "Chemistry of Melanins," in The Alkaloids, Vol. 36, A. Brossi, Ed. (Academic Press, 1989). (7) T. Horiuchi, Nature of damaged hair, Cosmet. Toiletr., 93, 65 (1978). (8) S. Kanetaka, K. Tomizawa, H. Iyo, and Y. Nakamura, The effect of UV radiation on human hair concerning physical properties and fine structure of protein, International Federation Societies of Cosmetic Chemists, Yokohama (1992). (9) R. Beyak, G. S. Kass, and C. F. Meyer, Elasticity and tensile properties of human hair. II. Light radiation effects, J. Soc. Cosmet. Chem., 22, 667•578 (1971). (10) F. G. Lennox and R. J. Rowlands, Photochemical degradation of keratins, Photochem. Photobiol., 9, 359-367 (1969). (11) L. J. Wolfram, "Reactivity of Human Hair, a Review," in Hair Research: Status and Future Aspects, Organos, Montagna, and Stiittgen, Eds. (1981), pp. 479-500. (12) C. R. Robbins and M. Bahl, Analysis of hair by electron spectroscopy for chemical analysis, J. Soc. Cosmet. Chem., 35, 379-390 (1984). (13) K. RiSper and E. Finnimore, Chemical structure of chromophores formed during photoyellowing of wool, Int. Wool Text. Res. Conf. Tokyo, IV, 21-31 (1985). (14) A Deftandre, J. C. Garson, and F. Leroy, Photoaging and photoprotection of natural hair, Interna- tional Federation Societies of Cosmetic Chemists Congress, New York, October 1990. (15) J. A. Swift and B. Bews, The chemistry of human hair cuticle. I. A new method for the physical isolation of cuticle, J. Soc. Cosmet. Chem. 25, 13-22 (1974). (16) D. H. Spackman, W. H. Stein, and S. Moore, Automatic recording apparatus for use in the chro- matography of amino acids, Anal. Chem., 30, 1190-1206 (1958). (17) U. Schumacher-Hamedat, J. FiShles, and H. Zahn, Intermediate steps in the oxidation of cystine in the bleaching process, Textilveredlung, 21, 121-125 (1986). (18) Commision Internationale de L'Eclairage (CIE): Empfehlungen fiir die Gesamt-bestrahlungsstiirken und die spektrale Verteilung kiinstlicher Sonnenstrahlung fiir Priifzwecke, CIE-Publication No. 20 (1972). (19) G. Geutler, MeJ3gutachten Lichttechnik TU Berlin (1988). (20) F. Leroy, A. Deftandre, and J. C. Garson, Photoaging of human hair, Haarwissenschaftl. Symp. Bad Neuenahr (Nov. 1990). (21) U. Schumacher-Hamedat, Modellstudien zur Entstehung von partiell oxidierten Cystin-derivaten bei oxidativer Veredlung von Wolle, Thesis RWTH Aachen (1986). (22) This radical reaction mechanism is suggested by the reviewer. (23) N. L. Sakina and A. E. Dontsov, Inhibition oflipid photooxidation by melanin, Biochem. USSR, 51, 744-747 (1986).

j. Soc. Cosmet. Chem., 46, 100-116 (March/April 1995) Fingerprinting of cosmetic formulations by dynamic electrokinetic and permeability analysis. II. Hair conditioners J. JACHOWICZ, Clairol Inc., 2 Blachley Road, Stamford CT Received October 26, 1994. Synopsis Dynamic electrokinetic and permeability analysis (DEPA) was employed to investigate complete formula- tions of rinse-off hair conditioners as well as several types of raw materials frequently used as active ingredients in such compositions. Quaternary ammonium surfactants, fatty amines, and silicone emulsions were employed as model systems. Zeta potential and permeability data collected before and after the treatment of hair plugs with 0.5% or 1% solutions of single- or multi-component solutions, respectively, allowed the comparison of their ability to modify hair surface. In general, the conditioners were found to deposit layers of surfactants or polymers with a thickness in the range of 0.6-3.2 •m as calculated from the permeability data obtained for the wet fibers. The systems containing positively charged species were also shown to reverse the surface charge of hair, while those based on neutral, fatty acid-fatty amine complexes or hydrocarbon oil (petrolatum) did not affect significantly the electrostatic surface characteristics. The removability of the conditioner residues was tested by consecutive application of a conditioner and a shampoo solution. The effectiveness of this process was gauged by comparing the thickness of the surface deposits and a value of zeta potential before and after the shampoo application. INTRODUCTION In a previous publication we described the application of dynamic electrokinetic and permeability analysis (DEPA) for testing the interactions of hair with shampoos (1). The technique enabled us to detect and quantify (in terms of streaming potential, zeta potentials, conductivity, and permeability) the adsorption and desorption of various shampoo ingredients on hair. We have now extended this line of research to the analysis of complete formulations of commercial and model hair conditioners. These composi- tions are usually based on surfactants, polymers, or oils possessing high affinity to keratin, and are formulated in such a way that the deposition of active materials occurs within a short period of contact time with the hair surface (2,3). The extent of the surface modification, which is related to the conditioning effect, can be controlled by the choice of the type and concentration of active ingredients, emulsifying agents, pH, etc. The author's present address is International Specialty Products, 1360 Alps Road, Wayne, NJ 07470. 100