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''This article contains a glossary section at the end.'' Many modern papermaking machines are based on the principles of the Fourdrinier Machine, which uses a specially woven plastic fabric mesh conveyor belt (known as a ''wire'' as it was once woven from bronze) in the forming section, where a slurry of fibre (usually wood or other vegetable fibres) is drained to create a continuous paper web. After the forming section the wet web passes through a press section to squeeze out excess water, then the pressed web passes through a heated drying section. The original Fourdrinier forming section used a horizontal drainage area, referred to as the ''drainage table''. Paper machines have four distinct operational sections: *Forming section, commonly called the wet end, is where the slurry of fibres filters out fluid a continuous fabric loop to form a wet web of fibre. *Press section where the wet fibre web passes between large rolls loaded under high pressure to squeeze out as much water as possible. *Drying section, where the pressed sheet passes partly around, in a serpentine manner, a series of steam heated drying cylinders. Drying removes the water content down to a level of about 6%, where it will remain at typical indoor atmospheric conditions. *Calender section where the dried paper is smoothened under high loading and pressure. Only one ''nip'' (where the sheet is pressed between two rolls) is necessary in order to hold the sheet, which shrinks through the drying section and is held in tension between the press section (or breaker stack if used) and the calender. Extra nips give more smoothing but at some expense to paper strength. Paper machines are long-lived assets that usually remain in service for several decades. It is common to rebuild machines periodically to increase production and improve quality or to change the paper grade. ==History of paper machines== Long before the invention of continuous paper making, paper was made in individual sheets by stirring a container of pulp slurry and either pouring it into a fabric sieve called a sheet mould or dipping and lifting the sheet mould from the vat. While still on the fabric in the sheet mould the wet paper is pressed to remove excess water and then the sheet was lifted off to be hung over a rope or wooden rod to air dry. In 1799, Louis-Nicolas Robert of Essonnes, France, was granted a patent for a continuous paper making machine.〔 At the time Robert was working for Saint-Léger Didot, with whom he quarrelled over the ownership of the invention. Didot thought that England was a better place to develop the machine. But during the troubled times of the French Revolution, he could not go there himself, so he sent his brother in law, John Gamble, an Englishman living in Paris. Through a chain of acquaintances, Gamble was introduced to the brothers Sealy and Henry Fourdrinier, stationers of London, who agreed to finance the project. Gamble was granted British patent 2487 on 20 October 1801. With the help particularly of Bryan Donkin, a skilled and ingenious mechanic, an improved version of the Robert original was installed at Frogmore Mill, Apsley, Hertfordshire, in 1803, followed by another in 1804. A third machine was installed at the Fourdriniers' own mill at Two Waters. The Fourdriniers also bought a mill at St Neots intending to install two machines there and the process and machines continued to develop. Thomas Gilpin is most often credited for creating the first U.S cylinder type papermaking machine at Brandywine Creek, Delaware in 1817. This machine was also developed in England, but it was a cylinder mould machine. The Fourdrinier machine wasn't introduced into the USA until 1827.〔Hills, Richard, "Papermaking in Britain 1488–1988", Athlone Press, 1988.〕 However, records show Charles Kinsey of Patterson, NJ had already patented a continuous process papermaking machine in 1807. Kinsey’s machine was built locally by Daniel Sawn and by 1809 the Kinsey machine was successfully making paper at the Essex Mill in Paterson. Financial stress and potential opportunities created by the Embargo of 1807 eventually persuaded Kinsey and his backers to change the mill’s focus from paper to cotton and Kinsey's early papermaking successes were soon overlooked and forgotten. Gilpin's 1817 patent was similar to Kinsey’s, as was the John Ames patent of 1822. The Ames patent was challenged by his competitors, asserting that Kinsey was the original inventor and Ames had been pilfering other peoples' ideas, their evidence being the employment of Daniel Sawn to work on his machine. The method of continuous production demonstrated by the paper machine influenced the development of continuous rolling of iron and later steel and other continuous production processes. 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「Paper machine」の詳細全文を読む スポンサード リンク
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