NEW APPROACHES TO HAIR SPRAY EVALUATION 629

630 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Figure 8. Photographs of PVP/VA formulation (Formulation õ, Table I) with and without 0.2 wt % Atmul 651K (õ60X magnification) shafts uniformly or evenly and there is little bonding between hair shafts however, the holding power is excellent. Coatability of PVP/VA, polyacrylic and carboxylated vinyl acetate copolymer (Resin R-l) formulations can be improved by addition of surfactants. Good visual examples of this are also possible with SEM t)hotomicrographs to reconfirm observations with the naked eye. Figure 8 shows a PVP/VA formulation with and without 0.2% Atmul 651K* (Formulation 3, Table I). Similar improvements in coatability were achieved by addition of 0.2•o Atmul 651K to a commercial product (Fig. 9). In gener. al, nonionic surfactants were the best of those evaluated while the anionics did not improve coatability. One cationic surfactant, stearyl dimethyl benzyl ammonium chloride, was beneficial with PVP/ VA. Those nonionic surfactants which improved coatability of the various resins are listed in Table II. The surfactants were found to be most effective at overall concentrations of 0.2% by weight. $Vhere coatability was improved, luster, appearance, and lack of flaking im- provements were apparent by qualitative evaluation. But, it should be reemphasized that curl retention improvement of any particular formulation Was much more dependent on the resin than on the coat- ability of the fihn on the hair fibers or the bonding of hair fibers with the film. However, it is reasonable to assume that if the inherently better-holding resins could be made to level better and increase bond- ing between fibers, their holding power would be even better. This is an objective for future work. * •tlas Chemicals Division, ICI America, Wilmington, Del.