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Papermaking is the process of making paper, a material which is used universally today for writing and packaging. In papermaking, a dilute suspension of fibres in water is drained through a screen, so that a mat of randomly interwoven fibres is laid down. Water is removed from this mat of fibres by pressing and drying to make paper. Since the invention of the Fourdrinier machine in the 19th century, most paper has been made from wood pulp because of cost. But other fibre sources such as cotton and textiles are used for high-quality papers. One common measure of a paper's quality is its non-wood-pulp content, e.g., 25% cotton, 50% rag, etc. Previously, paper was made up of rags and hemp as well as other materials. ==History== (詳細はChina about 105 CE, when Cai Lun, an official attached to the Imperial court during the Han Dynasty (202 BCE-220 CE), created a sheet of paper using mulberry and other bast fibres along with fishnets, old rags, and hemp waste.〔Papermaking. (2007). In: ''Encyclopædia Britannica''. Retrieved April 9, 2007, from Encyclopædia Britannica Online.〕 However a recent archaeological discovery has been reported from Gansu province of paper with legible Chinese writings on it dating from 8 BCE,〔(World Archaeological Congress eNewsletter 11 August 2006 )〕 while paper had been used in China for wrapping and padding since the 2nd century BCE.〔Needham, Joseph (1986). ''Science and Civilization in China: Volume 5, Part 1''. Taipei: Caves Books, Ltd. Volume 5, 122.〕 Paper used as a writing medium became widespread by the 3rd century〔Needham, Volume 5, 1.〕 and, by the 6th century, toilet paper was starting to be used in China as well.〔Needham, Volume 5, 123.〕 During the Tang Dynasty (618-907 CE) paper was folded and sewn into square bags to preserve the flavour of tea,〔 while the later Song Dynasty (960-1279 CE) was the first government to issue paper-printed money. In the 8th century, paper spread to the Islamic world, where the rudimentary and laborious process of papermaking was refined and machinery was designed for bulk manufacturing of paper. Production began in Samarkand, Baghdad, Damascus, Cairo, Morocco then Muslim Spain. In Baghdad, this was under the supervision of the Grand Vizier Ja'far ibn Yahya. In general, Muslims invented a method to make a thicker sheet of paper. This helped transform papermaking from an art into a major industry.〔Loveday, Helen. Islamic paper: a study of the ancient craft. Archetype Publications, 2001.〕 The earliest use of water-powered mills in paper production, specifically the use of pulp mills for preparing the pulp for papermaking, dates back to Samarkand in the 8th century. The earliest references to paper mills also come from the medieval Islamic world, where they were first noted in the 9th century by Arabic geographers in Damascus.〔 〕 Papermaking was diffused across the Islamic world, from where it was diffused further west into Europe. Modern papermaking began in the early 19th century in Europe with the development of the Fourdrinier machine, which produces a continuous roll of paper rather than individual sheets. These machines are considerably large, up to 150 meters in length, produce up to 10 meters wide sheet, and running around 100 km/h. In 1844, Canadian inventor Charles Fenerty and German inventor F.G. Keller had invented the machine and associated process to make use of wood pulp in papermaking.〔(Burger, Peter ). ''Charles Fenerty and his Paper Invention''. Toronto: Peter Burger, 2007. ISBN 978-0-9783318-1-8 pp.25-30〕 This would end the nearly 2,000-year use of pulped rags and start a new era for the production of newsprint and eventually almost all paper was made out of pulped wood. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Papermaking」の詳細全文を読む スポンサード リンク
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