Role of Hair Coverage and Sweating for Textile Friction on the Forearm

Abstract

Friction of textiles on the human forearm is an important factor in comfort sensations of garments. We built an experiment to measure friction for textiles sliding on the forearm under loading conditions which are characteristic for wearing shirts or jackets. The hair coverage of the participants’ forearm was quantified by image analysis of photographs of the arm in the region of contact. Friction results for five standard textiles suggest to treat hair coverage in two classes. Sweating after physical activity leads to an increase of friction by factors of 2 to 5 for participants with less hairy forearms, while an increase by a factor of 1 to 1.7 only was found for participants with more hairy forearms. We introduce a method of wetting the forearm of study participants in a controlled way with water, which results in similar friction as for the sweating forearm after physical activity. The method allows for efficient studies of the role of skin moisture for friction including varying hair coverage of the skin.

Multidimensional outline of experimental techniques for human skin tribology: A scoping review

“…Sweating increases the friction of hairy arms to a large extent in comparison to the non-hairy arms. 16 Tribological study of human skin is also used to study the feasibility of skin care products concluding volar forearm to be independent of age, gender and ethnicity. 77 Skin hydration leads to skin softening that tends to increase in contact area and ultimately increasing the adhesion phenomena which is specific to gender.…”

“…Frictional behaviour of human skin with materials popularly used in prosthetic development is investigated through sclerometer considering factors such as hair on skin, sweat, skin moisture, indentation, interaction velocity etc. 14 Role of hair and sweating on the skin-textile frictional characteristics of forearm is studied 16 through experimental setup as shown in Figure 9. Studies having forearm as site of investigation are tabulated in Table 3.…”

“…The structure of the human skin is composed of three layers -epidermis (0.7 mm), dermis (0.8 mm) and subcutaneous tissue (1.65-14.65 mm) being the innermost. Micro parameters affecting the friction of human skin are the ridges between the fingerprint in case of finger pad/tip and sole of the foot, Sweat secretion characterstics, 14,15 hair on skin, 16 textures, [17][18][19] relative humidity, [20][21][22] temperature, 20 hydration [23][24][25] etc. Factors affecting the human skin frictional behaviour are depicted in Figure 2.…”

“…Figure 9. (a) Digital photograph of the contact area, (b) binary version of the photograph, the fraction of black pixels of 6.3% is taken as the hair coverage, and (c) experimental setup for the measurement of sliding friction between textiles and the human forearm under conditions which are relevant for comfort sensations of garments 16. …”

Influences of Wettability and Geometry on Adhesion Force between Sportswear Fabric and Human/Artificial Skin

“…Studies on the interface between wet fabric and skin have shown that the friction force increases as the interface becomes saturated with water [16]. Liu also reported that the presence of body hair on the skin reduces the friction effect when water is added, suggesting that its impact may depend on the geometry of the skin [17]. While some models have been proposed to explain the contact Toshiaki Nishi 1) *, Atsushi Matsumura 1) , Manami Koshida 2) , Tatsufumi Matsumoto 2) and Takeshi Yamaguchi 1,3) between fabric and skin [18,19], the mechanism underlying the substantial increase in friction when water is introduced remains unclear [20].…”