Abstract
The water vapor permeabilities of polypropylene spunbond non-woven fabrics were investigated with varying the apparent density at 2$0^{\circ}C$, 3$0^{\circ}C$ and 4$0^{\circ}C$ by applying the hygroscopic method. At each temperature 50,65 and 80% PH conditions were used. The results indicated that the water vapor permeability rate increased with decreasing the distance between the sample fabrics and absorbent. The weight of permeated water vapor can be functionalibed with the distance between the sample fabrics and the absorbent as Y: ae-bx + c. The esutive distance between the sample fabrics and the absorbent was founto to be 0.92cm. Thus, all the measurements were made by setting the distance,0.75 cm, which is less than 0.92 cm, to maintain optimal measurement condition through out this work. The total water vapor permeability resistance of the sample was found to be independent of the temperature and the relative humidity used.