2023 Volume 74 Issue 9 Pages 499-510
Hygroscopically exothermic fibers have certain related issues: an excessive exothermic effect when the body is becoming hot and sweaty, and a low exothermic effect when it is cooling and perspiration is suppressed. The purpose of this study was to improve the properties of hygroscopically exothermic fibers by adhering microcapsules of a latent heat storage material as a core material to hygroscopically exothermic nonwoven fabrics.
The results revealed that the duration of the exothermic peak caused by exposure to high-humidity air was lengthened by increasing the adhesion rate of the microcapsules. The duration of a temperature increase of 2℃ or more was only 1 min 20 s in the nonwoven fabrics without adhesion, whereas it was 8 min 20 s in those with microcapsule adhesion (adhesion rate: 167%). This relatively long duration of the temperature rise was maintained even after switching back from high-humidity air to low-humidity air. In addition, this tendency became clearer when the melting point of the core materials of the microcapsules was lowered: the high-temperature state was maintained longer when materials with a melting point of 18.1℃ or lower were used.
