Lyocell is a new generic name given to a cellulosic fiber which is produced under an environmentally friendly process by dissolving cellulose in the tertiary amine oxide Nmethylmorpholine-N-oxide (NMMO). Lyocell fiber shows some superior characteristics over other cellulosic fibers; for instance, a high dry and wet tenacity and high wet modulus. For the majority of the last century, commercial route for the manufacturing of regenerated cellulosic fibers have given the scope for making a good cellulose solution by using an easy to dissolve derivative (e.g. xanthane in the case of viscose rayon) or complex (e.g. cuprammonium rayon). For this purpose advanced cellulosic fibers are defined as those made from a process involving direct dissolution of cellulose. The first example of such fibers has now been generically designed as lyocell fibers to distinguish them from rayon's, and the first commercial lyocell fiber is Courtaulds' Tencel.

This article will consider the range of aesthetic supplication possible and the dyeing and finishing techniques that can be used to generate them. It will also introduce a number of the innovative dyeing and finishing systems.

Lyocell is the first in a new generation of cellulosic fibers made by a solvent spinning process. A major driving force to its development was the demand for a process that was environmentally responsible which should utilize renewable resources as their raw materials. The first samples were produced in 1984 and commercial production started in 1988. A wide range of attractive textile fabrics can be made from Lyocell that are comfortable to wear and have good physical performances. This physical performances combined with its absorbency also makes Lyocell ideal for nonwoven fabrics and papers. The cellulose fibers produced by direct dissolution have the generic name of Lyocell.

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Originally Published in Textile Review, January-2012

Aravin Prince Periyasamy is an Asst Professor with D.K.T.E Society's Textile Engineering College, Ichalkaranji, Maharashtra & Murugesan Arumugam is Lecturer with SSM Institute of Textile Technology, Komarapalayam, Tamilnadu.