Viscose Fibers CV

Regenerated cellulosic fibers (Kiilter et al, 1990b) are produced according to the viscose spinning method, which is the most common process among the wet-spinning methods and consists of three steps  

The flow chart for the production of viscose is depicted in Fig. 2.26, and the spinning method is shown in Fig. 2.27. 

After spinning, the filaments need to be drawn so as to achieve a regular orientation of the chain molecules. The drawing procedure improves the fiber properties such as tenacity and abrasion resistance. The total draw ratio is about 20% for standard fibers and up to 150% for high-tenacity fibers. 

Right after spinning, the filament yarns or staple fibers are subjected to further treatments to remove impurities, to even out certain characteristics or increase the brightness, and to improve adhesive and frictional properties. These treatments include washing, desulfurization, bleaching, application of finish, and drying. 

The viscose spinning method is flexible in terms of chemical and physical process parameters, which allows manipulation of the properties of the final fibers to a great extent. On the basis of their properties, fibers are distinguished as (Kulter et al, 1990b)  

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