2023 Volume 74 Issue 12 Pages 704-713
This study investigated the wearing comfort of four types of summer undershirts with different fiber compositions and knitting structures under hot(30℃, 60% 35 RH) and comfortable (26℃, 55% RH) conditions. The purpose was to examine the characteristics of knitted fabrics preferred as summer underwear by comparing the wearing evaluations by young men and the internal environments of the clothing. The results of the wearing experiment are as follows.
(1) The relationship between the wearing evaluations and knitted fabric properties:
Sample A (58% nylon, 31% cupro, 11% polyurethane) and sample B (88% polyester, 12% polyurethane) received high ratings for thermal comfort, feel of fabric against the skin, and overall evaluation in both hot and comfortable environments. This may be attributed to the finer yarns, higher knitting density, and lower Sa roughness. In the hot and humid environment, sample B, with its thinner knitted fabric and higher air permeability, tended to receive higher ratings than sample A. Sample C (100% polyester) showed no significant difference from Samples A and B in thermal comfort in both environments, but received significantly lower skin feel ratings due to its lower knitting density, stiffness, and higher Sa roughness. Sample D, (100% cotton) was rated the lowest for all evaluation categories in both environments. The thicker knitted fabric and lower heat loss may have influenced the results. The differences in temperature and humidity inside the clothing among the samples were small. In the hot environment, significant negative correlation was observed between the temperature inside the clothing and the thermal comfort-related evaluations.
(2) Knitted fabric characteristics preferred for summer undershirts:
Knitted fabrics are desirable for both thermal and skin comfort in both hot and comfortable environments, with high thermal ratings being a major requirement in hot environments, and good skin comfort in comfortable environments. The results of multiple regression analysis indicate that the preferred knitted fabric for summer undershirts is thin and highly breathable, knitted with a high density of fine yarns, soft and flexible, and stretchable with the incorporation of a polyurethane blend.
