Comparison of the Swelling of Treated and Untreated Hair Using an Environmental Electron Microscope (ESEM)

The purpose of this work was to investigate the efficacy of ESEM for the study of hair under different relative humidity environments, as well as to measure integrity of the fiber after a relaxer treatment. In the past, the majority of work done on hair using electron microscopy has been conducted either in high vacuum on metallically coated fibers or at low voltage ( < 5 kV), both conditions being used to mitigate the adverse effects of charging [1]. While providing spectacular images of the cuticle, these images do not always relate to the state of the fiber under ambient conditions and thus must be interpreted with care. Not surprisingly dehydration under high vacuum conditions is one of the most deleterious aspects of conventional SEM studies. In this work we report on measurements of the swelling of hair fiber as a function of relative humidity in an Environmental SEM.