280 JOURNAL OF COSMETIC SCIENCE (2) J. A. Swift, Further comments on "Pathways for aqueous diffusion in keratin fibres," Text. Res. J., 70, 277-278 (2000). (3) F.-J. Wortmann, G. Wortmann, and H. Zahn, Pathways for dye diffusion in wool fibres, Text. Re•. J., 67, 720-724 (1977). (4) J. D. Leeder, J. A. Rippon, F. E. Rothery, and I. W. Stapleton, Use of transmission electron microscope to study dyeing and diffusion processes, Proc. 7th Int. Wool Text. Res. Conf, Tokyo, 5, 99-108 (1985). (5) J. D. Leeder, Comments on "Pathways for aqueous diffusion in keratin fibres," Text. Res. J., 69, 229 (1999). (6) J. A. Swift, Electron histochemistry ofcystine containing proteins in thin transverse sections of human hair. J. Royal Microscop. Soc., 88, 449 (1968). (7) C.L. Gummer, R. P. R. Dawber, and V. H. Price, Trichothiodystrophy: An electron-histochemical study of the hair shaft, Br. J. Dermatol., 110, 439-449 (1984).

J. Cosmet. Sci., 52, 281-295 (September/October 2001) Dynamic hairspray analysis. II. Effect of polymer, hair type, and solvent composition j. JACHOWICZ and K. YAO, International Specialty Products, Wayne, NJ 07470. Accepted for publication May 31, 2001. Synopsis A texture analyzer was employed to study the properties of hairspray resins by measuring a number of mechanical parameters of hair modified by them. Hairset stiffness, stiffness retention at high humidity, and duration and magnitude of polymer film tackiness during drying were the properties employed to charac- terize fixative-treated hair. They were investigated for formulations containing ethyl ester of PVM/MA copolymer, butyl ester of PVM/MA copolymer, vinyl caprolactam/PVP/dimethylaminoethyl methacrylate copolymer, VA/butyl maleate/isobornyl acrylate copolymer, and polymer blends such as poly(methylvi- nylether) (PMVE) - ethyl ester of PVM/MA copolymer. It was demonstrated that the properties of hair treated with a fixative are affected by the concentration and molecular weight of a polymer, low-molecular- weight additives that can modify the mechanical, surface, or interfacial properties of a polymer film, and the presence of water in the formulation. It was also shown, that the type of hair employed, such as virgin, untreated hair or hair damaged by bleaching, can also have an effect on the performance of a given hairspray formulation. For compositions based on blends of PMVE and ethyl ester of PVM/MA copolymer, the employed method demonstrated the sensitivity of the properties of polymer blends to the presence of a hydrophilic component such as PMVE. INTRODUCTION It has been shown in previous studies that hairsprays, and hair fixatives in general, can be analyzed in terms of several measurable parameters to characterize their consumer- perceptible attributes. Dynamic hairspray analysis, which employs a texture analyzer for mechanical measurements, was recently used to collect data on hairset stiffness, stiffness retention at high humidity, and duration and magnitude of polymer film tackiness during drying (1). It was suggested that these parameters can be affected by (a) the concentration and molecular characteristics of a principal polymeric component of a fixative system, (b) the properties of an interface between a polymer and the hair surface, (c) the low-molecular-weight additives that can modify the mechanical, surface, or interfacial properties of a polymer film (for example, plasticizers), and (d) the type and/or composition of a solvent. For a system containing a single resin, the key parameters are the molecular weight of a polymer and its concentration in the formulation. In a two-component polymer system, frequently employed in commercial formulations, com- position is an important parameter since it determines the polymer blend properties. 281