The cotton fiber, the fleece from the sheep, and the flax must be processed to be made ready for the spinning plant. Raw cotton is put through the cotton gin, which removes seeds and other impurities, before the fiber is shipped in bales to the spinning mill. Various mechanical and chemical operations convert flax into spinnable linen fiber; wool must be sorted, graded, and scoured before it is ready for mill processing into yarn. Silk is unwound from cocoons after the silk gum is softened in warm water to permit ready separation without rupturing the fine fibers. The continuous filaments are gathered and twisted to form multifilament yarns, in a process known as throwing. Broken filaments and waste are converted to staple (short fibers) for manufacture into spun silk yarns, in a manner similar to that used for spinning cotton, wool, or linen fibers.
Synthetic fibers are supplied in either filament or staple form. The continuous filament fiber is processed into yarn in the same manner as silk. Synthetic staple fiber, which consists of short lengths of fiber, is processed as are raw cotton and wool before