Yarn is divided into:
① staple fiber yarn, by the short fiber (natural short fiber or chemical fiber cut-section fiber) by spinning processing, divided ring, free end spinning yarn, such as yarns.
② continuous filament, such as natural silk and synthetic filament, divided by or without the addition of, smooth filament or deformation filament.
③ short fiber and continuous filament combined yarn, such as polyester filament core-spun yarn.
The line is composed of two strands or more than two strands of single yarn combined. The fineness of the yarn can be expressed in many ways, such as number, metric number, Imperial count, Dan Neil, etc. (see count). The twist of the yarn is indicated by the number of twists per metre or inch. The direction of the twist is divided S-Twist and Z-Twist. In a certain twist range, the strength of the yarn increases with the increase of twist. The twist of single yarn and the twist of strand are chosen according to the use of strand. Usually the single yarn and the Strand line use opposite twist, namely ZS or SZ. There is an optimum ratio between single yarn and strand, in which the strength of strand line increases with the increase of strand ratio, and the strength of strand line decreases when it exceeds the critical value. Fiber properties and spinning methods play a decisive role in the performance of yarns. Ring yarn In the twisting process, due to the transfer of fiber, from the yarn inside to the outer layer, and then from the outer layer to the inner layers, repeatedly transferred, the fiber around the yarn axis is helical, spiral radius along the axis of alternating increase or decrease. At this time the length of the fiber more tend to the axis of yarn, the length of the short fiber more tend to the outer layer of yarn. The fineness of the fiber tends to the axis of the yarn, and the fineness of the coarse fiber tends to the outer layer of the yarn. The fibers with small initial modulus are more in the outer layer, and the fibers with large initial modulus are more in the inner layers. Reasonable selection of different characteristics of the fiber, can be spun into different styles of yarn, to adapt to different fabric use or improve the performance. As the chemical fiber can arbitrarily choose the length, fineness and Fiber section shape, the coat fabric should be selected fiber slightly thicker, slightly shorter length of the chemical fiber and cotton blended, in order to increase the wool-like texture of the yarn surface. Underwear fabric should choose fiber slightly thin, longer length of chemical fiber, so that the cotton fiber in the outer layer of the yarn in order to improve moisture absorption and wear comfort. Free-end spinning includes airflow spinning, electrostatic spinning, eddy current spinning yarn, as a result of twisting when the fiber inward transfer less, the core and the outer layer, the inner tight outside loose, the structure is loose, the fiber straightness is poor, the fiber between the holding force is poor, the yarn strength is low, but the dyeing sex and wear-resisting property is good.
Self-twisting spinning yarn is also called spin yarn, is the use of rubbing roller on the need to produce periodic positive and negative to the false, yarn on the occurrence of periodic no point, so the strength is lower, general partnership into the stock line after weaving.
Filament yarn is made of filament (such as natural silk, chemical fiber wire or rayon) and together with the loading bundle, mainly polyester filament, viscose filament, nylon filament and so on. Fancy yarn is mainly expressed as the change of yarn appearance or color. Mainly wrapped, core, bamboo, big belly, color points, waveforms, braids, towels, circles, seeds, feathers, toothbrushes, centipedes, belts, Duan Dyeing, snow Neil and so on.