Abstract
The luster of human hair was studied in relation to the physical properties of hair surface. The luster was evaluated by means of Rod Method (visual evaluation) and Goniophotometry (instrumental evaluation). From the relationship between both methods, it was found that it may be possible to evaluate the luster of human hair by S value as a parameter.
In order to clarify the factors which influence the luster of human hair, the physical properties of lusterous hair were compared with those of non-lustrous hair. The factors discussed here were as follows: (1) refraction index of hair surface, (2) Number and width of hair cuticles, (3) Number of cuticle cell layers. The physical properties, from root end to tip, of human hair were also investigated in relation to the luster.
In addition, the effects of cosmetic treatments such as cold waving, brushing and blowing with heat were examined. Brushing and cold waving were found to have a great effect on the decrease of the luster.
