Thermal Comfort Properties of Bi-Layer Knitted Fabrics

Transmission of sensible and insensible perspiration is an important factor for fabric comfort. Improvement in the thermal comfort properties of knitted fabrics results in the achievement of fabric comfort. In this research, the thermal comfort properties of six bi-layer knitted fabrics were studied. The bi-layer knitted fabrics were made with different combinations of yarn in the inner layer and outer layer. The yarn combinations selected were polyester staple yarn-polyester staple yarn, polyester staple yarn-cotton, cotton-cotton, polypropylene-cotton, micro denier polyester-cotton, and micro denier polyester- micro denier polyester for the inner and outer layers, respectively. To find the thermal comfort properties of the six bi-layer knitted fabrics, an objective fabric test was carried out. The results showed that the bi-layer fabrics made from micro denier polyester, both in the inner and outer layers, exhibit better thermal comfort properties, thereby providing a higher level of comfort; hence, they are preferred for active sportswear. The water vapour permeability, air permeability, thermal resistance and thermal conductivity of the bi-layer knitted fabric made up of micro denier polyester as the outer and inner layer were found to be higher when compared to the other bi-layer structures. The results were discussed together with one – way ANOVA test results at a 0.05 significance level.