Yarn is divided into:
① "Short fiber" and "continuous filament" combined yarn, such as: polyester-cotton filament core-spun yarn, etc.
② "Continuous filament": such as: natural silk and chemical fiber filament, with or without twist, smooth filament or textured filament, etc.
③ "Short fiber yarn": It is processed by spinning short fibers (natural short fibers or chemical fiber cut fibers), and is divided into ring-spun yarn, free-end spinning, self-twisted yarn, etc.
The thread is made of two or more single yarns that are combined and twisted.
There are many ways to express the fineness of yarn, such as: number, metric count, imperial count, denier, etc. (see count).
The twist of the yarn is expressed in twists per meter or inch. The direction of the twist is divided into S twist and Z twist.
The twist direction of "single yarn" and the twist direction of the strands are selected according to the use of the strands.
Usually "single yarn" and "strand" adopt the opposite direction, namely ZS or SZ.
The properties of the fibers and the spinning method play a decisive role in the properties of the yarn.
At this time, the fibers with long length tend to tend to the axis of the yarn more, and the fibers with short length tend to tend to the outer layer of the yarn. The finer fibers tend to the axis of the yarn, and the coarser fibers tend to the outer layer of the yarn. The fibers with smaller initial modulus are more located in the outer layer, and the fibers with larger initial modulus are more located in the inner layer.
Reasonable selection of fibers with different properties can be spun into different styles of yarns to adapt to different fabric uses or improve wear performance. Since chemical fibers can be arbitrarily selected in terms of length, fineness and fiber cross-sectional shape, the outerwear fabrics should be blended with cotton and chemical fibers with slightly thicker fibers and shorter lengths to increase the texture of the yarn surface.
Open-end spinning includes yarns spun by air spinning, electrospinning, vortex spinning, etc. Due to the less transfer of fibers inward when twisting, the yarn core is tighter on the inside and loose on the outside than the outer layer, the structure is looser, and the fiber straightness Poor, the cohesion between fibers is poor, the yarn strength is low, but the dyeability and wear resistance are good.
The yarn spun by self-twisted spinning is also called self-twisted yarn. It uses the twisting roller to produce periodic positive and reverse false twists on the whiskers. Periodic non-twist points appear on the finished yarn, so the strength is low. The strands are then woven.
Filament yarn is a bundle of filaments (such as natural silk, chemical fiber or rayon) combined together; mainly polyester filament, viscose filament, nylon filament, etc.
Fancy yarn is mainly manifested as a change in the appearance or color of the yarn. There are mainly wrapping, core wrapping, bamboo knots, pot belly, colored dots, waveforms, braids, towels, circles, knots, feathers, toothbrushes, centipedes, belts, segment dyeing, chenille and so on.