Lyocell Fiber

 This is the primary requirement. The content of impurities and defects (such as fused fibers, hard lumps, etc.) must be extremely low to ensure the production process remains uninterrupted by filter clogging and to guarantee the cleanliness and safety of the final product, especially for hygiene and medical supplies.

 Length: Varies according to the specific process. Spunlace nonwovens commonly use 38mm or 40mm; needle-punched nonwovens may utilize longer fibers, like 51mm or even longer, to enhance fiber entanglement and fabric strength.
 Linear Density:  The range is broad, from the standard 1.7 dtex to finer versions like 1.3 dtex or coarser ones. Fine denier fibers yield softer products with a smoother surface, while coarser denier fibers provide better bulkiness and strength.

 This is a critical indicator for spunlace nonwovens. Conventional viscose fiber has low wet strength and tends to break easily under the high-pressure water jets. In contrast, the high wet strength characteristic of lyocell fiber allows it to perfectly withstand the spunlacing process without significant fiber breakage, resulting in strong, uniform nonwoven fabrics.

 The spin finish applied to the fibers must be compatible with the nonwoven manufacturing process. For instance, it should be easily removable during the spunlacing process and not interfere with subsequent hydrophilic or hydrophobic treatments.