title: Influence of internal structures of hair fiber on hair appearance. III. Generation of light-scattering factors in hair cuticles and the influence on hair shine.
abstract: The effects of thermal treatments on hair fiber induced by blow-drying have been investigated. It was found that the hair shows whitish and powdery appearance after heat drying, especially when dark hair is rapidly dried from a wet condition. For all kinds of hair, the appearance of numerous glittering speckles was confirmed on the cuticle surface by optical microscopic observations. SEM images of hair transverse and longitudinal sections with glittering speckles revealed that the splitting of cuticle layers generated by blow-drying occurred not only at the outermost parts of cuticle cells but also at the inner parts of the cellular interfaces. The release and uptake of moisture through fiber surfaces induces deformation of cuticle cells, probably because of anisotropic swelling or drying of the cells. The cuticles with glittering speckles are found to be fragile and are easily damaged in combination with other mechanical stresses such as combing force. Furthermore, the authors have found an efficient system for both improving hair shine and preventing cuticle damage caused by the blow-drying/combing process.
authors.affiliation: Kao Corporation, Analytical Research Center, 1334 Minato, Wakayama-shi, Wakayama 640-8580, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Okamoto
authors.forename: Ryoko
authors.initials: R
authors.lastname: Yakawa
authors.forename: Akira
authors.initials: A
authors.lastname: Mamada
authors.forename: Shigeto
authors.initials: S
authors.lastname: Inoue
authors.forename: Shinobu
authors.initials: S
authors.lastname: Nagase
authors.forename: Satoshi
authors.initials: S
authors.lastname: Shibuichi
authors.forename: Emiko
authors.initials: E
authors.lastname: Kariya
authors.forename: Naoki
authors.initials: N
authors.lastname: Satoh
mesh_terms: D000328:Adult; D005260:Female; D006197:Hair / Q000648:ultrastructure; D006801:Humans; D008027:Light; D008855:Microscopy, Electron, Scanning; D012542:Scattering, Radiation; D017550:Spectroscopy, Fourier Transform Infrared