TAGS: Skin Care
Kao Corporation’s Skin Care Research Laboratory, Makeup Research Laboratory and Analytical Science Laboratory have analyzed the skin protection functions of the ultra-thin membrane formed by Fine Fiber Technology. The technology forms a layered, ultra-thin membrane which feels light, soft and natural on the skin surface by directly spraying superfine fibers with submicron diameter.
Examines Structure of Fine Fiber Membrane
Kao has examined the functionality of this ultra-thin membrane and elucidated various functions, including the function of keeping the skin in good condition by controlling the transpiration of moisture from the skin surface when the skin is covered with the fine fiber membrane, and the function of smoothing skin roughness and covering spots to obtain a beautiful finish by applying base makeup cosmetics on the fine fiber membrane. This study examined the structure of the fine fiber membrane that protects the skin.
The average diameter of the minute gaps formed by the interfolded fine fibers is 1.8 microns. The fine fiber membrane has a three-dimensional structure in which superfine fibers are interfolded, and contains innumerable minute gaps. In this study, Kao measured the sizes (pore diameter distribution) of these minute gaps using a porosimeter. The results confirmed that the pore diameter of the fine fiber membrane was approximately 1.8 microns, and that this size, which was compared with the sizes of atmospheric pollutants (dirt), could capture PM2.5.
Ultra-thin Membrane Suppresses Dirt Adhesion
A fine fiber membrane was formed on a model skin, and observed by electron microscope after atmospheric pollutants (dirt) such as pollen, dust, graphite and PM2.5 adhered to the membrane. The images confirmed that these atmospheric pollutants were retained within the gaps of the fine fiber membrane or on top of the membrane. Furthermore, removing the membrane with these particles (dirt) adhering to it resulted in nearly complete removal of the atmospheric pollutants from the model skin. Thus, the fine fiber membrane formed on the skin acts like a filter that captures various pollutants and prevents them from adhering to the skin.
Kao's researchers confirmed the protection effects from physical stimulations (such as abrasion and chafing) when a fine fiber membrane was formed on the skin. Five men and women in their 20s to 30s as test participants were asked to wear a face mask for approximately four hours after a formulation which remains on the skin for a certain period was applied and a fine fiber membrane was formed on only one cheek. The residual state of the formulation and the fine fiber membrane on the skin was compared between the two cheeks immediately after putting on a mask and after wearing the mask for four hours, and the degree of abrasion was visualized and quantified.
Membrane Reduces Abrasion and Chafing
The results showed that both the fine fiber membrane and the formulation remained on the skin on the cheek where fine fibers were applied even when the mask was removed after four hours, while most of the film formed by the formulation had disappeared on the cheek where the fine fiber membrane was not applied. This indicates that the fine fiber membrane formed on the skin not only retains the formulation but also reduces the abrasion and chafing by the mask.
Kao's past studies have revealed that a high capillary force acts on the fine fiber membrane due to its porous structure. This led to the expectation that sebum, which is secreted from the skin, may be adsorbed on the inner surface of the membrane, and so tests were conducted.
A fine fiber membrane was formed on one cheek of 29 women in their 20s to 50s, and the sebum was collected from the skin of both cheeks by wiping with a cigarette paper after four hours to quantify the amount of sebum by liquid chromatography-mass spectrometry (LC/MS). The results showed that more sebum remained on the cheek to which the fine fiber was not applied than on the cheek to which it was applied. LC/MS quantification of the fine fiber membrane that was removed from the skin also showed that approximately 70 percent of the secreted sebum had transferred to the membrane.
Kao Corporation hopes to apply these findings of Fine Fiber Technology to areas of high interest, such as air pollution, and to propose new applications. Kao will continue developing products with new perspectives.
Source: Kao