1. They belong to regenerated cellulose fibers:
Regenerated cellulose fibers are made from natural cellulose such as cotton short staple, wood, bamboo, bagasse, reed, etc. by chemical treatment and mechanical processing.
Viscose, Modal, Lyocell, Triacetate, Polynosic, Cupro and bamboo fibers belong to the category of regenerated cellulose fibers.
2. Viscose and Rayon:
First of all, it needs to be clear that Viscose and Rayon represent viscose fibers, no difference.
Viscose Rayon is also used to represent viscose fibers in some places.
In Europe, the ISO standard used Viscose, while the FTC used Rayon, and later approved Vicose of ISO.
In order to distinguish viscose filaments from staple fibers, some people in China use Viscose to represent filaments, call it rayon, Rayon to represent staple fibers, call it rayon.
3. Modal:
Modal belongs to High-wet-modulus (HWM) regenerated cellulose fibers. (See Table 1, Category II)
In the early 1940s, Japan developed viscose staple fibers with high wet modulus, called "Toramomen Kapok Tiger". China also produced this kind of fiber in 1965, named "Rich and Strong Fiber", or "Rich Fiber" for short. This kind of fiber overcomes the fatal shortcomings of viscose fiber, and its performance is close to that of cotton fiber. In the early 1950s, high wet modulus viscose fibers were industrialized.
The most famous is Lenzing Company of Austria, which named regenerated cellulose fibers with high wet modulus Lenzing Modal. Later, the term Modal was used as a synonym for viscose fibers with high wet modulus. Now the ISO standard already has Modal fiber classification, textile tags can be used to identify Modal.
4. Tencel and Lyocell:
Tencel is the trademark name of Lyocell fiber produced by Acocdis Company, UK. It is registered in Chinese as Tencel. The Lyocell fibers of Lenzing, Austria, are named Lenzing-Lyocell.
Interestingly: In 2004, Austria acquired Tencel subsidiary of Acordis, so Tencel became Lenzing's trademark.
Lyocell fibers belong to high strength regenerated cellulose fibers. (see Table I, Category III) was officially named by the International Commission on Man-made Fibers and Synthetic Fibers in 1989.
FTC in the United States has used Lyocell as a classification under viscose fibers for textile labeling.