A technical overview of thermal comfort properties of bi-layer knitted sportswear: A review

This study investigates the thermal comfort characteristics of various bi-layer knitted fabrics constructed using Modal/Bamboo yarn for the outer layer and Microfiber polyester, polyester, or acrylic yarn for the inner layer. A total of seven different bi-layer knitted textiles were produced, and their comfort properties were evaluated through both objective and subjective assessments. The results revealed that the bi-layer fabric with a one-tuck point, made with bamboo as the outer layer, exhibited the best performance. It demonstrated lower moisture absorption and superior air permeability, water vapor permeability, wicking ability, and drying rate compared to the other materials tested. Bi-layer knitted fabrics are being explored due to their advantages over single-layer knits, including better breathability, thermal insulation, and moisture-wicking capabilities. Furthermore, the study provides valuable scientific insight into how different fabric structures and fiber compositions affect thermal comfort. It also discusses various methods for evaluating these comfort-related properties, such as air and water vapor permeability, wicking, and drying rate. These findings can help textile manufacturers develop more advanced, functional sportswear that offers improved comfort and performance for the wearer. In39 addition, by understanding the fabric structure–performance relationship, the research supports innovation and potential use of eco-friendly materials in bi-layer fabric construction.