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Show How Cellophane Is Made From Spruce Wood Pulp TUa firct cton in the. m a ntif artnre I nriH solution onH fnwmo The first step in the manufacture of cellophane is steeping sheets of pure spruce wood pulp in a caustic soda solution. This converts the pulp sheets into alkali cellulose. The sheets are then dumped into hoppers leading to shredding machines. ma-chines. After shredding the cellulose cellu-lose is white and fluffy, and looks like bread crumbs. Carbon disul-phide disul-phide is then added, changing the cellulose cel-lulose crumbs into an orange color. This is dissolved in another caustic - JL acid solution, and forms vicose which ripens under carefully controlled con-trolled conditions. Then it goes to a casting machine, where in an acid bath it is coagulated from a liquid into a solid film, and then it rolls along through one bath after another, an-other, becoming progressively purer, pur-er, more transparent, tougher and more pliable. Then it goes through heavy squeeze rolls, which press out all the liquid. Then it is wound on a core as the finished product. |