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contour pillows - Filaments are doubled and twisted into smooth, si_lklike yarns or cut into staple lengths and spun. Spun rayon can be treated to simulate wool, linen, or cotton. There are four methods of manufacturi_ng rayon, using different materials and processes. In the nitrocellulose process developed by Chardonnet, no longer of commercial importance, cellulose is treated with nitric and sulf_uric acids. In the viscose process discovered in 1892, it is treated with carbon disulfide, then dissolved in caustic soda, forced through a spinneret, and hardened in sulf_uric acid. Viscose rayon is the most important type commercially, being used in most kinds of weari_ng apparel, f_urniture fabric, and carpets. For cuprammonium rayon, the cellulose is dissolved in copper oxide and ammonia,
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forced through holes larger than the intended diameter, then, by a process known as stretch spinning, is elongated and twisted under tension to yield a very fine, strong yarn used for sheer fabrics and hosiery. Rayon produced by these three methods is classified as regenerated, since the final product, like the original material, is cellulose. The fourth type, saponified acetate rayon, originated in England in 1918, is an acetate derivative of cellulose made by steeping cellulose in acetic acid, then treating it with acetic anhydride. Acetate rayon is more resistant to stains and creasing, is plasticized by heat, and requires special dyes, thus allowing two-tone effects with a single dye when acetate is combined with other fibers. An acetate filler is used to make shatterproof glass.
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