VISUALIZING HAIR LIPIDS BY ASE-SEM 301 Figure 2. SEM images of transversely polished hair planes without ASE (a) and with ASE (b). ASE-SEM image (b) includes a circular pattern (CP) and a stitch pattern (SP) in the magnified image of the cortex. Cu: cuticle. Co: cortex.

302 JOURNAL OF COSMETIC SCIENCE Figure 3. ASE-SEM images of transversely polished hair planes at no tilting angle (a) and at a tilting angle of 45 degrees (b) toward the primary electron beam. The arrow in each image shows the same region. Figure 4. A TEM image (a) of a transversely ultra-thin section of a hair fiber and an ASE-SEM image (b) of the adjacent hair plane. The arrows in each image show the same regions. suggests that CP and SP in ASE-SEM images correspond to melanin granules and the CMC, respectively (Figure 4). EFFECTS OF HAIR TREATMENTS ON ASE-SEM IMAGES The effects of various treatments of hair fibers on ASE-SEM images of the polished hair planes were then examined. When a hair fiber was treated with a mixture of CHC1 3 / CH 3 OH/water (v/v/v 18:9:1) for 24 hr at room temperature, SP but not CP disappeared in the ASE-SEM images (Figure Sb compare with the untreated control, Figure Sa). On