Toray developed a polyester woven knit that looks like natural fibres, which is named RIRANCHA S2. For the new product, the original yarn is designed to have a structure in which large and small cross-sectional surfaces have alternately appeared along a longitudinal direction, by a special technique of twisting yarns. The structure having different surface sizes reduces an area of contacting the fabric into a user’s skin, and allows not to stick with each other. Also, in the structure, gaps between the original yarns are made larger than those between fabrics made of normal polyester finished yarns, and such gaps allow sweat to be absorbed well and make the fabric breathable. It has water absorbability about 35% higher than that of normal polyester finished yarns. Titanium oxide applied in high concentration suppresses visible light transmission on the fibre surface, which means that the chemical compound helps the fabric lower a level of being see-through. Toray’s aim is to supply it widely in ladies’ and gentlemen’s apparel markets.

JCFA News Letter (No.16) September, 2018/Japan Chemical Fibers Association