Chemical fiber. The chemical fibers are produced artificially and are classified into two large groups: semi-synthetic fibers and totally synthetic fibers. This term comprises all fibers artificially produced from macromolecular materials by nature. These fibers are given the generic name rayon, because "artificial silk" has fallen into disuse. They are also known as "regenerated cellulose fiber" or "regenerated fiber." They are industrial derivatives of cellulose, cellulose nitrate or cellulose acetate that through a chemical process are converted into new fibers. Rayon fibers are made from cellulose extracted from the pulp. First, cellulose is dissolved in various chemicals. The resulting liquid is pumped through conduits or holes, called "rows," and is immersed in another chemical solution, where it solidifies into fine strands. Several of these strands are twisted (spun) together to produce rayon yarn with which the fabrics and clothing are woven.