Nbsp; nbsp; synthetic filament is composed of several single fibers, such as 165dtex/48f, which means that 48 single fibers are combined into 165dtex composite filament. In the production process, the filament must go through winding, merging, twisting, finishing and other processes under the stress state, while in the weaving process, it must undergo repeated friction of guide rollers, heddles and reeds. The friction of silk yarn is more than ten thousand times, while the speed of water-jet loom is usually 500-700 r/min. The high-speed friction monofilament is very easy to fuzz, which not only affects the weaving efficiency, but also leads to the failure of weaving seriously, and the quality of products is obviously reduced. Therefore, sizing of non-twisted or low-twisted filaments is necessary. Sizing warp yarn can withstand friction during processing and weave smoothly, and ensure product quality.
Sizing mechanism
After sizing, the slurry forms a layer of sizing film around the silk body to resist the friction of various equipment; and the slurry penetrates into the single fibers, which binds the single fibers, improves the clustering and strength of the multifilament, so as to ensure the smooth completion of the tasks of the later process. Because of the hairiness of staple yarn, the sizing effect requires that the material should be mainly covered, while the sizing of synthetic filament should be mainly permeated and supplemented by draping. Because of the low moisture regain, the standard moisture regain of polyester filament is 0.8 dtex (70 denier) nylon filaments consist of 16, 18, 36 and 48 single filaments. This kind of synthetic filament often needs sizing before it can be woven. If the single filament number of polyamide filament is reduced to less than 10 by reducing the number of single filament and increasing the diameter of polyamide filament, no sizing is needed, as long as the warp axle is woven by oil or wax treatment during warping. However, this method is difficult to use because the reduction of the number of single filaments or the increase of the diameter will harden the handle and make the appearance of the fabric worse, especially for polyester filament fabrics.
