Cotton, wool and other fibers to twist back wrapped yarn called staple fiber yarn, the structure of the complex and due to the spinning method of twisting slightly different. Generally speaking, in the center of the yarn is composed of fiber-dense core, and the yarn on the surface of the fiber head exposed to form a fluff area. The structure of a spun staple yarn shows that there are more and more complicated links between the layers of the yarn core than filament yarns. There are many fiber junctions in low-quality staple yarns. Due to the random arrangement of fibers, along with the change of twist and fineness, the coarse detail of the yarn length is caused. With the addition of different methods, the quality and uniformity of staple yarn is still very big difference.
The short staple yarn structure is expanded, the appearance is plump, has the good adiabatic and the comfortable feeling; this is mainly due to the void in the yarn that contains air.