Recycled fabric. Regenerated fiber, also known as rayon, is made by dissolving cellulose such as straw and bark and spinning. Although recycled fibers have good hand feel, hygroscopicity and air permeability, they are processed by chemical processes, so there must be chemical residues, and their environmental protection performance is worse than that of natural fibers such as cotton.

Commonly have
1. Viscose fiber, which has good moisture absorption performance (standard moisture regain rate is 14%), good air permeability, and is more comfortable to wear; in addition, there are some recycled fiber fabrics such as acetate fiber and cupro fiber (standard moisture regain rate is about 4%) ), although the moisture absorption and air permeability are good, the strength will be significantly reduced after sweat absorption or washing, and the clothes will be easily damaged if the strength decreases.
2. The sources of rayon are petroleum and biology. The rayon derived from biology is called regenerated fiber. The preparation method of regenerated fiber is to extract pure α-cellulose (called pulp) from cellulose raw materials, and use caustic soda. , carbon disulfide treatment to obtain orange-yellow cellulose sodium xanthate, which is then dissolved in dilute sodium hydroxide solution to become a viscous spinning dope, called viscose.
The viscose is filtered, aged (placed at a certain temperature for about 18 to 30 hours to reduce the degree of esterification of cellulose xanthate), and after defoaming, wet spinning is carried out. The coagulation bath is composed of sulfuric acid, sodium sulfate and sulfuric acid. Zinc composition.
The cellulose sodium xanthate in the viscose is decomposed by the action of sulfuric acid in the coagulation bath, the cellulose is regenerated and precipitated, and the obtained cellulose fiber becomes viscose fiber after washing, desulfurization, bleaching and drying. Because carbon disulfide in production is toxic, it is easy to catch fire and explode when mixed with air, so it is necessary to treat the three wastes (exhaust gas, waste water and waste residue), and pay attention to labor protection and safety.