Human hair: A unique physicochemical composite

Anatomy and Physiology of Hair

“…Several microfibrils come together to form larger units called macrofibril which represents almost 50% of the cortex material. The cortex comprises the bulk of the shaft and also contains melanin [2,15,16] Medulla is located in the center of the hair shaft preferably presented in coarser fibers. The hair medulla contains structural proteins that are markedly different from other hair keratins and eosinophilic granules that are filled by an amino acid, citrulline and eventually form internal coatings within the membranes of mature cells [14,16,17].…”

“…Cuticle has also important protective properties and barrier functions against physical and chemical insults [14][15][16].…”

Biology of Human Hair: Know Your Hair to Control It

“…Hair reactivity is complex and depends not only on the presence of reactive groups in the fibre, but also on their availability. The latter is significantly affected by fibre morphology and molecular structure [2]. Hair is mostly proteinaceous in nature, while structural lipids and other materials represent only a minor fraction of its constituents.…”

“…The amino acid makeup of the protein components was reviewed by Wolfram and is depicted in Fig. 1 [1,2,18,19].…”

Friction and Surface Temperature of Wet Hair Containing Water, Oil, or Oil-in-Water Emulsion

“…Bhushan and Speakman et al indicated that an increase in moisture increases the elasticity and frictional resistance of human hair 3,4 . In addition, Wolfram found a deformation of the cuticle layer on the hair s surface due to swelling 5 . Furthermore, the surface properties of human hair are changed by adsorption of oil or surfactant molecules.…”