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beaded pillows - As early as 1665 the English naturalist Robert Hooke had suggested the possibility of making artificial si_lk, but the first artificial textile fiber was produced in 1884 by a French scientist, Hilaire de Chardonnet, and was manufactured by him in 1889. Unpopular at first because it was too lustrous and laundered poorly, it has been steadily improved. Cellulose, originally from cotton linters but now chiefly from wood pulp, washed, bleached, and pressed into sheets, is dissolved by chemicals, then forced under pressure through minute holes in a metal cap (spinneret), emerging as filaments that unite to form one continuous strand solidified by passage through a suitable liquid or warm air. The spinning solution may be forced through a larger
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orifice or slit to produce a monofilament, a ribbon, or a sheet. 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.
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