In recent years, regenerated cellulose fibers (such as viscose, Modal, Tencel and other fibers) have continued to appear, meeting people’s needs in a timely manner, while also partially alleviating today’s problems of resource scarcity and damage to the natural environment.
Because regenerated cellulose fiber has the dual performance advantages of natural cellulose fiber and synthetic fiber, it is being widely used in textiles on an unprecedented scale.
Today we will take a look at the differences between the three most common fibers: viscose fiber, modal fiber, and lyocell fiber.
1 Ordinary viscose fiber
Viscose fiber (Viscose) , the full name of viscose fiber, is a cellulose fiber obtained by extracting and reshaping fiber molecules from natural wood cellulose using “wood” as the raw material.
Preparation method
It is made by alkalizing plant cellulose Alkali cellulose reacts with carbon disulfide to form cellulose xanthate, which is dissolved in dilute alkali solution and the resulting viscous solution is called viscose. The viscose is made into viscose fiber after wet spinning and a series of processing steps.
The unevenness of the complex molding process of ordinary viscose fibers will make the cross-section of ordinary viscose fibers waist-round Or irregular, with holes inside and irregular grooves longitudinally. Viscose has excellent hygroscopicity and dyeability, but its modulus and strength are low, especially the wet strength.
2 Modal fiber
Modal fiber It is the trade name of high wet modulus viscose fiber. The difference between it and ordinary viscose fiber is that Modal fiber improves the shortcomings of low strength and low modulus of ordinary viscose fiber in the wet state. It also has high strength and modulus, so it is often called high wet modulus viscose fiber.
Similar products from different fiber manufacturers also have different names, such as Austrian Lenzing Company’s ModalTM brand fiber (Lenzing ModalTM), glass Nosik fiber (Polynosic), Fuqiang Fiber, tiger kapok and Newal (Newal) and other product names.
Preparation method
High wet modulus properties are obtained by Given by the special craftsmanship of the production process. The differences from the general viscose fiber production process are:
(1) Cellulose should have a high average degree of polymerization (about 450).
(2) The prepared spinning solution has a higher concentration.
(3) Prepare the appropriate coagulation bath composition (such as increasing the content of zinc sulfate), and reduce the coagulation bath temperature to slow down the molding speed, which is beneficial to obtaining a dense structure and crystallinity Higher fiber. The inner and outer layers of the fiber obtained in this way have a relatively uniform structure. The sheath-core structure of the fiber cross-section is not as obvious as that of ordinary viscose fibers. The cross-sectional shape tends to be round or waist-round, and the longitudinal surface is also smooth. The fiber is in the wet state. It has high strength and modulus, and its excellent hygroscopic properties are also suitable for underwear.
The structure of the inner and outer layers of the fiber is relatively uniform. The sheath-core structure of the fiber cross-section is not as obvious as that of ordinary viscose fiber. The cross-sectional shape tends to be round or waist-round, and the longitudinal direction is smooth. It has high strength and modulus in wet state, and has excellent hygroscopic properties.
3 Lyocell fiber
Lyocell fiber is made from natural cellulose polymer and is a kind of man-made cellulose fiber. It was invented by the British Cotauer Company and later produced by the Swiss Lenzing Company. The trade name is Tencel. The trade name in my country adopts its homophonic “Tencel”.
Preparation method
Lyocell is an aqueous solution of N-methyl morphine oxide (NMMO) As a solvent, cellulose pulp can be directly dissolved to obtain a spinning solution, and then a wet spinning or dry-wet spinning method can be used to shape the fiber using a certain concentration of NMMO-H2O solution as a coagulation bath, and then the spun fiber can be A new type of cellulose fiber made from virgin fibers by stretching, washing, oiling and drying.
Compared with conventional viscose fiber production methods, the biggest advantage of this spinning method is that NMMO can directly dissolve cellulose pulp and spin The production process of the original solution can be greatly simplified, and the recovery rate of NMMO can reach more than 99%, and the production process hardly pollutes the environment.
The morphological structure of Lyocell fiber is completely different from that of ordinary viscose. The cross-sectional structure is uniform and round, and there is no distinction between skin and core layers. The longitudinal surface is smooth and has no grooves. Has specific viscosityThe fiber has excellent mechanical properties, good dimensional stability when washed (shrinkage is only 2%), and high hygroscopicity. Beautiful luster, soft hand feel, good drape, and good elegance.
The difference between viscose, modal and lyocell
1 Fiber cross section
2 Fiber characteristics
Viscose fiber
It has good hygroscopicity and meets the physiological requirements of human skin. The fabric is soft, smooth, has good air permeability, is not prone to static electricity, is anti-ultraviolet, comfortable to wear, easy to dye, and has bright color after dyeing. It has good color fastness and good spinnability. The wet modulus is low, the shrinkage is high and it is easy to deform. It feels hard after being put into water, and has poor elasticity and wear resistance.
Modal fiber
Soft to the touch, Smooth and clean, bright color, good color fastness, particularly smooth fabric feel, bright cloth surface, better drape than existing cotton, polyester, and viscose fiber, with the strength and toughness of synthetic fibers, and silk-like luster The fabric has wrinkle resistance and easy-iron properties, and has good water absorption and air permeability, but its fabric has poor stiffness.
Lyocell fiber
Tools The various excellent properties of natural fibers and synthetic fibers include natural luster, smooth hand feel, high strength, basically no shrinkage, good moisture and air permeability, softness, comfort, smoothness and coolness, good drape, and durability.
3 Scope of application
Viscose fiber
Short fibers can be spun purely or blended with other textile fibers, and are suitable for making underwear, outerwear and various decorative items. The filament fabric is light and thin. In addition to being suitable for clothing, it can also be used to weave quilts and decorative fabrics.
Modal fiber
Modal knitting The fabric is mainly used to make underwear, but also used in sportswear, casual wear, shirts, high-end ready-to-wear fabrics, etc. Blending with other fibers can improve the shortcomings of poor stiffness of pure Modal products.
Lyocell fiber
Covers all fields of textile, whether cotton, wool, silk, High-quality and high-end products can be produced in linen products, knitting or woven fields. </p
