Okamoto Masayuki, Yakawa Ryoko, Mamada Akira, Inoue Shigeto, Nagase Shinobu, Shibuichi Satoshi, Kariya Emiko, Satoh Naoki
Kao Corporation, Analytical Research Center, 1334 Minato, Wakayama-shi, Wakayama 640-8580, Japan.
J Cosmet Sci. 2003 Jul-Aug;54(4):353-66.
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.
人们已经对吹干引起的热处理对头发纤维的影响进行了研究。结果发现，热干燥后头发呈现出发白且粉状的外观，尤其是深色头发从湿润状态快速干燥时。通过光学显微镜观察，对于所有类型的头发，在角质层表面都证实出现了大量闪闪发光的斑点。带有闪闪发光斑点的头发横切面和纵切面的扫描电子显微镜图像显示，吹干产生的角质层分层不仅发生在角质细胞的最外层，也发生在细胞界面的内部。水分通过纤维表面的释放和吸收会引起角质细胞的变形，这可能是由于细胞的各向异性膨胀或干燥所致。发现带有闪闪发光斑点的角质层很脆弱，并且在与梳理力等其他机械应力共同作用时很容易受损。此外，作者还发现了一种有效的系统，既能改善头发光泽，又能防止吹干/梳理过程对角质层造成损伤。
