Lyocell

Lyocell is the cleanest of the regenerated-cellulose fibers, a kind of rayon made by dissolving wood pulp, often eucalyptus, in a non-toxic solvent and spinning it back into thread in a closed loop that recovers almost all of the solvent for reuse. That process makes it far less polluting than ordinary viscose rayon, and the fiber itself is soft, strong even when wet, breathable, and biodegradable. First developed in the 1970s and commercialized in the 1990s, it is widely sold under the brand Tencel, and it is the fiber most often reached for when a soft, silky cloth with a smaller environmental footprint is wanted.