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Summary: The comfort in wear of textiles has been studied extensively on the level of textile construction. The influence of the fibre material is present in the experience of textile consumers, but objective assessment is rather difficult. Some recent works are reviewed here. TENCEL® is a man-made cellulosic fibre of the generic fibre type lyocell. The background of the special comfort in wear of textiles made from TENCEL® fibres is explained as a consequence of the fibres' water-absorbing nanostructure. The basis for these properties are found in the high absorption of water and water vapour, which leads to high heat capacity and heat balancing effect for thermoregulation, comparable with the action of phase change materials. The thermal wear properties resulting are the cool and dry touch, the active cooling effect in sports wear, and the warming properties when used as an insulation layer. These effects are to a certain extent adaptive to the environment, providing comfort in a wide range of climatic conditions. Moreover, neutral electric properties, retarded bacterial growth and good skin sensory perception add to the overall skin friendly properties, which were also shown in wear studies with patients suffering from skin diseases.

Efficient stabilization of cellulose solutions in NMMO(1) against side reactions and their harmful effects meansprevention of both homolytic and heterolytic side reactions, which is mainlyaccomplished by trapping radicals, formaldehyde, andN-(methylene)iminium ions (5). Whileradical trapping is commonly reflected by the antioxidativeefficiency, the effectivity against heterolyticdegradationin the Lyocell dope can be expressed by the newly introduced term‘formaldehyde trapping capacity’ (FTC). Propyl gallate (PG,4), the most widely applied Lyocell stabilizer nowadays, actsas a phenolic antioxidant, and is finally oxidized to a deeply colored, highlyconjugated chromophore (11) via ellagicacid (10). It was demonstrated that 4 is alsoa quencher of formaldehyde and N-(methylene)iminium ions,both in organic solutions of NMMO and in Lyocell dope. The processes of radicaltrapping and scavenging of HCHO/5 are competitive in the caseof propyl gallate. A novel oxa-chromanol derivative, PBD (14),was designed as stabilizer for Lyocell solutions. In analogy to propyl gallate,PBD acts as a scavenger of all three dangerous species, namely HCHO,5 and radicals. Upon oxidation by radical species, PBDreleasesacetaldehyde which acts as a very efficient HCHO trap. Thus, in contrast topropyl gallate, radical trapping and HCHO trapping are not competitive. Boththeantioxidative efficiency and the capacity to trap HCHO and 5are higher for PBD as compared to propyl gallate. In preliminary stabilizertesting, mixtures of PBD and PG proved to be especially effective.

Regenerated cellulosic fibers, such as viscose, modal and lyocell, combine the advantages of natural and synthetic fibers and offer unique properties in textile and nonwoven applications. Their production is feasible under environmentally friendly and essentially pollution-free manufacturing conditions. The viscose production line at Lenzing AG, Austria, which is based on dissolution of cellulose, is a simple and intrinsically clean route to regenerated fibers. The fiber products are presented, including recent developments of specialty fibers.