The fabric usage and the number of spinning branches determine the fiber size and the number of single fibers. With the same size of the core filament, the finer the filament and the more the number of filaments, the fabric is soft and smooth; On the contrary, the less the number of pieces, the harder and straighter the fabric. In the case of no need to consider the luster of the core wire for the coated products, the smooth core wire can be used to reduce the production cost; For bare products, the luster of the core wire should be considered, and the smooth core wire should be avoided as far as possible, so that the product will produce aurora and affect the use effect. If 11.8tex (50s) polyester cotton core spun yarn is produced, 5.56tex (50D) / 24F polyester semi smooth filament should be selected as shirt or skirt fabric, and 5.56tex (50D) / 24F ordinary low tensile strength fiber should be selected. Generally, polyester core spun yarn with high gloss length, high elongation and single filament number of 7.78tex (70D) / 36F is used for sewing. 56 tex (68D) / 36F polyester fiber is used as a burnt out coat. However, as the core spun yarn used in rags, the size of core yarn is relatively large. Generally, 7.22-8.33tex (65-75d) / 36F polyester filament is used, and light or semi light can not be used, so as to avoid too thin and too thin rags, resulting in Aurora. The elastic fabric adopts the core spun yarn, and the size of the core yarn can be selected according to the usage. The draw ratio of ordinary polyester 7.78 tex (70D) spandex is about 3.8 times that of polyester fiber. When the size of spandex core yarn is moderate (medium and low count), the strength of spandex core yarn is high, up to 3.8 ~ 4.0 times, which ensures that stretch pants, hips and knees have greater elasticity. Second, the choice of outsourcing fiber.
If the cotton fiber is used for the outer packing cotton, theoretically, the long count raw cotton should be used with high maturity. However, if high-speed sewing thread is not used to make shirt fabric or skirt material, or other fancy decorative cloth, it is unnecessary to use high-quality raw cotton, because there is no need to experience strong friction and high-temperature melting like high-speed sewing thread, so there will be no "peeling" phenomenon, and 30mm long raw cotton can meet the requirements. However, as cotton fiber is the core spun yarn of rags, its neps and impurities are less. If it is wrapped with cotton, it has low strength, good dyeability and less impurity neps.
