Viscose rayon fiber is a kind of medium and heavy fiber with good strength and wear resistance. It has hydrophilic property (the moisture regain is 11%). This fiber can be dry cleaned and can be washed under good condition. It will not produce static electricity or pilling, and the price is not expensive.
Rayon will lose 30% to 50% strength in wet state, so when washing, it needs to be careful, after drying, the strength can be recovered (improved viscose rayon - HWM viscose fiber, without this problem), the elasticity and resilience of rayon are poor, and it will shrink greatly after washing, and it is also moldy moth.
1. strength is high. Short fiber strength is 2.6 to 5.7cN/dtex, and high strength fiber is 5.6 polyester.
8.0cN/dtex. Because of its low moisture absorption, its wet strength is basically the same as that of dry state. The impact strength is 4 times higher than that of nylon and 20 times higher than that of viscose fiber.
2. good elasticity. The elasticity is close to wool, and when the elongation is 5% to 6%, it can almost completely recover. Wrinkle resistance is better than other fibers, that is, the fabric is not wrinkled and has good dimensional stability. The modulus of elasticity is 22 to 141cN/dtex, 2~3 times higher than that of nylon.
3. heat resistance and thermal stability are the best among synthetic fabrics.
4. the surface of polyester is smooth, and the internal molecules are tightly arranged.
5. good wear resistance. Wear resistance is second only to the best wear-resistant nylon, which is better than other natural fibers and synthetic fibers.
6. good light resistance. Light resistance is second only to acrylic fiber.
7. corrosion resistance. It is good for bleaching agents, oxidants, hydrocarbons, ketones, petroleum products and inorganic acids. Weak alkali resistant, not afraid of mold, but hot alkali can be decomposed.
8. dyeability is poor, but color fastness is good, and it is not easy to fade.
The shrinkage rate is closely related to the composition of the fabric and the fiber characteristics of the fabric, the fabric structure and the processing process. The hygroscopicity of all kinds of fibers is different. The shrinkage of the fibers with high moisture absorption is large, whereas the shrinkage rate is small. The hygroscopicity of natural fibers, such as cotton, wool, silk and hemp, is relatively large, and the rate is large, and the moisture absorption of polyester and polypropylene fibers. The tight structure of the knot will also affect the shrinkage of the fabric. The shrinkage of the fabric with loose structure is larger than that of the close structure. The shrinkage of some common fabrics is provided for reference. Cotton mercerized flat cloth: the shrinkage rate is 3.5%, latitude 3.5%; cotton mercerized twill cloth: the shrinkage rate is 4%, the weft is 3%; the cotton is plain cloth: the shrinkage rate is 6%, the weft is 2.5%; the general worsted wool: the shrinkage rate is 4%, the weft to 3.5%; the silk crepe de crepe is to 10%, and the weft is 3%.