Abstract
The most important function of clothing is to protect the wearer from the environment and to feel comfortable in as wide a range of environment as possible. The suitable clothing for any conditions requires the passage of moisture and heat through clothing.
This paper deals with the water vapor permeabilities through fiber beds and fabrics. The principal measuring way is humidity gradient method and is compared with weighing method using a cup. The humidity gradient method is useful for the evaluation of the moisture-transfer through clothing which is putted on.
The following results are obtained;
(1) The vertical distributions of relative humidity over samples change linearly in the region up to 10mm height above. This region is considered as the diffusion layer.
(2) The rate of moisture-transfer depends on the air gap between water surface and sample. Therefore it is important to keep a constant air gap for correct measurement.
(3) A protective cover is used to avoid disturbing the diffusion layers over sample. Height of cover influences the rate of moisture-transfer, and especially in the presence of air movement, rate of moisture-transfer about no cover of a sample without cover cannot be evaluated precisely by humidity gradient method.
(4) To obtain sufficient correspondence between humidity gradient method and weighing method needs a protective cover with adequate height.
