The cellulose wood pulp is dried to produce hard sheets of purified cellulose, also known as “dissolving pulp” or “dissolving cellulose” from selected wood chips or bamboo stalks. The purified cellulose sheets are sometimes bleached with sodium hypochlorite (NaOCl) to remove remaining color. The preprocessing removes most of the lignin, hemicelluloses, free sugars, mineral salts, and starches found in plant cell walls along with cellulose. The resulting purified cellulose sheets contain 87% to 98% long-chain cellulose molecules. Wood chips that are commonly used include spruce, pine, hemlock, beech, and the leaves and inner pith of bamboo. The preprocessing chemicals and amounts used will vary according to the different types of wood.