A METHOD FOR THE DETERMINATION OF VISCOELASTIC PARAMETERS OF HUMAN HAIR IN RELATION TO ITS STRUCTURE

An analytical model and the corresponding experimental procedure are p resented, which make it possible to separately analyze the viscous and elastic components of human hair. Moreover, a computerized experiment al system is described with which a standardized quantitative determin ation of the most important mechanical parameters of human hair can be performed. Comparative investigations of the mechanical behavior of h air specimens obtained from the frontoparietal and occipital scalp reg ions of 10 healthy human subjects showed no statistically significant differences with regard to their mechanical parameters. Nevertheless, the paired analysis of the mechanical parameters of thin and thick hai r specimens revealed that the values of two of these parameters are si gnificantly higher in thin than in thick hair specimens. These finding s suggest that there are mechanical parameters of human hair related t o gross hair morphology, whereas others depend on hair microstructure.