Lee Yoonhee, Kim Youn-Duk, Hyun Hye-Jin, Pi Long-Quan, Jin Xinghai, Lee Won-Soo
Department of Dermatology and Institute of Hair and Cosmetic Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea.
Ann Dermatol. 2011 Nov;23(4):455-62. doi: 10.5021/ad.2011.23.4.455. Epub 2011 Nov 3.
Hair dryers are commonly used and can cause hair damage such as roughness, dryness and loss of hair color. It is important to understand the best way to dry hair without causing damage.
The study assessed changes in the ultra-structure, morphology, moisture content, and color of hair after repeated shampooing and drying with a hair dryer at a range of temperatures.
A standardized drying time was used to completely dry each hair tress, and each tress was treated a total of 30 times. Air flow was set on the hair dryer. The tresses were divided into the following five test groups: (a) no treatment, (b) drying without using a hair dryer (room temperature, 20℃), (c) drying with a hair dryer for 60 seconds at a distance of 15 cm (47℃), (d) drying with a hair dryer for 30 seconds at a distance of 10 cm (61℃), (e) drying with a hair dryer for 15 seconds at a distance of 5 cm (95℃). Scanning and transmission electron microscopy (TEM) and lipid TEM were performed. Water content was analyzed by a halogen moisture analyzer and hair color was measured with a spectrophotometer.
Hair surfaces tended to become more damaged as the temperature increased. No cortex damage was ever noted, suggesting that the surface of hair might play a role as a barrier to prevent cortex damage. Cell membrane complex was damaged only in the naturally dried group without hair dryer. Moisture content decreased in all treated groups compared to the untreated control group. However, the differences in moisture content among the groups were not statistically significant. Drying under the ambient and 95℃ conditions appeared to change hair color, especially into lightness, after just 10 treatments.
Although using a hair dryer causes more surface damage than natural drying, using a hair dryer at a distance of 15 cm with continuous motion causes less damage than drying hair naturally.
电吹风被广泛使用,且会导致头发损伤,如毛糙、干枯和褪色。了解在不造成损伤的情况下吹干头发的最佳方法很重要。
本研究评估了在一系列温度下用吹风机反复洗发和吹干后头发的超微结构、形态、水分含量和颜色的变化。
使用标准化的干燥时间将每束头发完全吹干,每束头发共处理30次。在吹风机上设置气流。将发束分为以下五个测试组:(a) 不处理,(b) 不使用吹风机干燥(室温,20℃),(c) 在距离15厘米处用吹风机吹干60秒(47℃),(d) 在距离10厘米处用吹风机吹干30秒(61℃),(e) 在距离5厘米处用吹风机吹干15秒(95℃)。进行扫描和透射电子显微镜(TEM)以及脂质TEM检测。通过卤素水分分析仪分析水分含量,并用分光光度计测量头发颜色。
随着温度升高,头发表面往往受损更严重。从未观察到皮质损伤,这表明头发表面可能起到防止皮质损伤的屏障作用。仅在自然干燥且未使用吹风机的组中观察到细胞膜复合物受损。与未处理的对照组相比,所有处理组的水分含量均降低。然而,各组之间的水分含量差异无统计学意义。在环境温度和95℃条件下干燥,仅经过10次处理后似乎就会改变头发颜色,尤其是亮度。
虽然使用吹风机比自然干燥造成更多的表面损伤,但在距离头发15厘米处持续移动使用吹风机比自然吹干头发造成的损伤更小。