title: Accurate determination of the structural elasticity of human hair by a small-scale bending test.
abstract: This paper reports on a small-scale bending method for human hair. The test sample, which is elliptical in cross-section, is fixed to a hollow steel needle using resin to form a cantilever. A loading probe is used to subject this to a lateral load, where the load is applied parallel to either the long or short axis of the elliptical cross-section. From these tests, load-displacement relationships for the hair were obtained. From the experimental data and analysis, we found that the structural elasticity determined is independent of the direction of bending, and precise measurements of the structural elasticity of human hair with scattering of less than 5% were realized using this test scheme. Finally, changes in the structural elasticity of hair due to hair treatments were detected and the changes are discussed based on a theoretical model of the multi-layered structure.
authors.affiliation: Department of Nanomechanics, Tohoku University, Sendai, Japan. tohmyoh@ism.mech.tohoku.ac.jp
authors.forename: Hironori
authors.initials: H
authors.lastname: Tohmyoh
authors.forename: Mitsuharu
authors.initials: M
authors.lastname: Ishihara
authors.forename: M A Salam
authors.initials: MA
authors.lastname: Akanda
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yamaki
authors.forename: Tomoko
authors.initials: T
authors.lastname: Watanabe
authors.forename: Tokuro
authors.initials: T
authors.lastname: Iwabuchi
mesh_terms: D004548:Elasticity / Q000502:physiology*; D006197:Hair / Q000502:physiology*; D006801:Humans; D008954:Models, Biological; D016474:Weight-Bearing / Q000502:physiology*