Function of Environmental Humidity Control of Commodity Textiles

The function of environmental humidity control (B-value) of Nylon6 fabric, Rayon fabric and Tencel fabric was evaluated as the representative of commodity textiles showing a moisture sorption-desorption. B-value of these textiles was depending on their moisture sorption: the nearly same value as Woolen fabric for Rayon fabric, the somewhat higher value than Cotton fabric for Tencel fabric and the considerably lower value than Cotton fabric for Nylon6 fabric were obtained at the specimen's weight of 0 to 20g/a volume of closed vessel (V=0.012m3). The change of moisture sorption in each textile during measurement of B-value was given as the difference between the moisture sorption isotherm at the side of lower temperature (25°C) and the moisture desorption isotherm at the side of higher temperature (35°C) . Based on this fact, the calculated relation curve of B-value and specimen's weight (g/V), using the moisture sorption isotherm at 25°C and the moisture desorption isotherm at 35°C, agreed well with the observed one. Furthermore, the B-values at 7.5g/V of a mixture composed of various fabrics including fabrics in previous paper [Sen'i Gakkaishi, 52, 234 (1996)], basically, was given as the average value with a mixed ratio of the B-value at 7.5g/V of its each component. Moreover, even if the relation curves of B-value and Wo/V between each component in a mixture was markedly different, it was given as the conversion B-value for a kind of component which was determined in this paper.