Regenerated Textile
Regenerated cellulose textile material is produced by extruding a dissolved wood pulp solution into an acidic spinning bath. Wood pulp is chemically converted into a soluble xanthate before being spun into fine filaments. Viscose staple fiber represents the most common form of this material, produced in short, discrete lengths suitable for blending with cotton or wool.
This fiber combines the comfort and moisture absorption of natural cotton with the processing uniformity of a manufactured yarn.
Manufacturing Sequence
Steeping dissolving pulp in concentrated sodium hydroxide represents the first stage of the chemical conversion process, producing alkali cellulose. This alkali cellulose is aged to reduce the degree of polymerization to the target level before being reacted with carbon disulfide to form sodium cellulose xanthate. Dissolving this xanthate in a dilute sodium hydroxide solution yields the viscous spinning solution known as viscose.
Extruded through fine spinneret orifices into an acid coagulation bath containing sulfuric acid, sodium sulfate, and zinc sulfate, the xanthate decomposes to regenerate the solid cellulose filaments. These continuous filaments are then stretched to align the polymer chains, washed to remove chemical residues, and cut to the desired staple length.
Performance Attribute
High moisture regain and excellent dyeability distinguish this fiber from synthetic alternatives like polyester or nylon. The amorphous region within the regenerated cellulose structure allows water molecules and dyestuffs to penetrate easily, resulting in vibrant colors and excellent comfort in next-to-skin garments. However, the wet strength of standard viscose staple fiber is lower than its dry strength, requiring careful tension control during fabric wet processing.
To mitigate this drop in wet performance, manufacturers can adjust the coagulation bath parameters to produce a higher proportion of crystalline regions in the fiber structure.
Commercial Tolerance
Fiber length and linear density are measured continuously during the extrusion and cutting stages to ensure consistency across production lots. Standard commercial fiber shipments must fall within tight tolerances of the nominal staple length and decitex values to prevent yarn irregularities during high-speed spinning operations. Deviations outside these ranges lead to uneven yarn formation and defects in the final woven fabric.
