Acetate (Triacetate). The oldest man-made fibre and the first one made using tree pulp.
Filament fibres having a practically unlimited or infinite length are called filaments. Filament fibres are continuous (long) fibre. It may be natural like silk or synthetic like Nylon. Filament fibres are measured in yards or meters.
Man-made fibre. Viscose and Acetate, derived from cellulose, were almost all the human-made fibres in existence before World War II. During the 1930s, after intensive fibre research, several new synthetic fibres were produced which led to the production of nylon.
Textile Fibre Overview with links
Viscose or rayon is an artificial fibre, made from wood pulp, which on the face of it seems more sustainable. However, often the tree planted is eucalyptus, which draws up large amounts of water, causing problems in sensitive landscapes.