664 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS aerosol product. In Fig. 7, it is noted that even though release does occur each time the sample is wetted, the subsequent releases are nominal in comparison to the first. No attempt was made to determine whether or not the formulation changes shown in Table III also affect the release of the aluminum chlor- hydrate. It may be postulated, however, that these changes would affect any dispersed, water-soluble material in the aerosol formulations. We retained the IPM-based aerosol, antiperspirant formulation for the re- maining tests. A number of successive tests were run on a small sample of human subjects of both sexes. It was attempted to establish the range of release characteristics that might be encountered in a broader sampling of sub- jects. This was accomplished by increasing or decreasing the subject's perspiration rate artificially (Fig. 8). In addition, subjects were chosen who represented a considerable difference in normal perspiration rate. Figures 9 and 10 show the variations between two subjects using the same aerosol antiperspirant formulation and encapsulated perfume. Figure 9 shows that the particular subject perspired considerably even before heat was applied, as indicated by the letter, P, at the 5-hour mark. Neverthe- less, release still occurred after 8 hours. It is noted that even though considerable variation does occur from subject to subject repeated release is evident in each case. This demon- lo 9 4 o 3 J IIIIII ENCAPSULATED OIL - OIL ..... RELATIVE WATER VAPOR 1 2_ 3 4 5 6 7 13 TIME HOURS Figure 8. Fragrance release by induced perspiration

ENCAPSULATED PERFUMES 665 strates that the delayed and gradual release of perfume in aerosol prod- ucts can be realized. Antiperspirant products could probably be formu- lated to fulfill specific time-release requirements as well as for subjects lO 9 o 6 4 ¸ o 3 _ IIIIIII ENCAPSLIL01LWATERRbLATIVE ..... VAPOR lO 9 8 7 6 5 ,4 3 2_ 1 2 3 z$ 5 6 7 TIME HOURS Figure 9. Fragrance release with calm snbject " mm mm mm mm mm mm mm mm '' m m m m m m• m m " m m '' m m m m m m llIlII ENCAPSULATED OIL _L •m OIL .... RELATIVE WATER VAPOr 1 2 3 4 5 6 7 8 9 TIME HOURS Figure 10. Fragrance release with nervous subject