256 JOURNAL OF THE SOCIETY OF COSMETIC CtlEMISTS oo-'1- -t I I I '• I ool o-t- +l+l+l+l+l+l+l+l+l+l+l+l+l+lffl+l+l+l

11.0 10.0 9,0 8,0 7,0 6.0 5,Q 4.,0 3.0 2.0 1,0 EFFECTS OF COSMETIC INGREDIENTS 257 -10 -5 0 5 10 15 20 25 30 35 Temperature tn øC Figure 2. Effect of temperature on normalized modulus values. Stratum corneum extended under solution and normalized to the value for water at 37øC -e-e-e-glycerol:water (1:1) to exert any influence on chapping or related skin disorders, since the temper- ature of the face and hands does not reach 18øC until the air temperature drops to about -12øC [extrapolated from data of Phelps and Vold (7)]. However, the temperature of the lower extremities can reach 18øC at an ambient temperature as high as 19øC (8). The effects of a variety of cosmetic ingredients and of a few chemical treat- ments on the physical properties of stratum corneum at 31% RH are summa- rized in Table I. In examining these data, it must be remembered that only horizontal comparisons are possible since the "control" and "treated" samples