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  • Cotton is a soft, staple fiber that grows in a form known as a boll around the seeds of the cotton plant (Gossypium sp.), a shrub native to tropical and subtropical regions around the world, including the Americas, India and Africa. The fiber most often is spun into yarn or thread and used to make a soft, breathable textile, which is the most widely used natural-fiber cloth in clothing today. The English name, which began to be used circa 1400, derives from the Arabic (al) qutn قُطْن, meaning cotton

    History

    Cotton was cultivated by the inhabitants of the Indus Valley Civilization by the 5th millennium BCE - 4th millennium BCE.[2] The Indus cotton industry was well developed and some methods used in cotton spinning and fabrication continued to be used until the modern Industrialization of India. Well before the Common Era the use of cotton textiles had spread from India to the Mediterranean and beyond.

    According to The Columbia Encyclopedia, Sixth Edition:

    "Cotton has been spun, woven, and dyed since prehistoric times. It clothed the people of ancient India, Egypt, and China. Hundreds of years before the Christian era cotton textiles were woven in India with matchless skill, and their use spread to the Mediterranean countries. In the 1st cent. Arab traders brought fine muslin and calico to Italy and Spain. The Moors introduced the cultivation of cotton into Spain in the 9th cent. Fustians and dimities were woven there and in the 14th cent. in Venice and Milan, at first with a linen warp. Little cotton cloth was imported to England before the 15th cent., although small amounts were obtained chiefly for candlewicks. By the 17th cent. the East India Company was bringing rare fabrics from India. Native Americans skillfully spun and wove cotton into fine garments and dyed tapestries. Cotton fabrics found in Peruvian tombs are said to belong to a pre-Inca culture. In color and texture the ancient Peruvian and Mexican textiles resemble those found in Egyptian tombs."

    The earliest cultivation of cotton discovered thus far in the Americas occurred in Mexico, some 5,000 years ago. The indigenous species was Gossypium hirsutum which is today the most widely planted species of cotton in the world, constituting about 90% of all production worldwide. The greatest diversity of wild cotton species is found in Mexico, followed by Australia and Africa.

    In Peru, cultivation of the indigenous cotton species Gossypium barbadense was the backbone of the development of coastal cultures such as the Norte Chico, Moche and Nazca. Cotton was grown upriver, made into nets and traded with fishing villages along the coast for large supplies of fish. The Spanish who came to Mexico in the early 1500s found the people growing cotton and wearing clothing made of it.

    During the late medieval period, cotton became known as an imported fiber in northern Europe, without any knowledge of how it was derived, other than that it was a plant; noting its similarities to wool, people in the region could only imagine that cotton must be produced by plant-borne sheep. John Mandeville, writing in 1350, stated as fact the now-preposterous belief: "There grew there [India] a wonderful tree which bore tiny lambs on the endes of its branches. These branches were so pliable that they bent down to allow the lambs to feed when they are hungrie [sic]." (See Vegetable Lamb of Tartary.) This aspect is retained in the name for cotton in many European languages, such as German Baumwolle, which translates as "tree wool" (Baum means "tree"; Wolle means "wool"). By the end of the 16th century, cotton was cultivated throughout the warmer regions in Asia and the Americas.

    India's cotton-processing sector gradually declined during British expansion in India and the establishment of colonial rule during the late 18th and early 19th centuries. This was largely due to the East India Company's exposing of India to foreign competition, which made cotton processing and manufacturing workshops in India uncompetitive. Indian markets increasingly supplied only raw cotton and were obliged to purchase manufactured textiles from Britain.

    The advent of the Industrial Revolution in Britain provided a great boost to cotton manufacture, as textiles emerged as Britain's leading export. In 1738 Lewis Paul and John Wyatt, of Birmingham, England, patented the Roller Spinning machine, and the flyer-and-bobbin system for drawing cotton to a more even thickness using two sets of rollers that traveled at different speeds. Later, the invention of the spinning jenny in 1764 and Richard Arkwright's spinning frame (based on the Roller Spinning Machine) in 1769 enabled British weavers to produce cotton yarn and cloth at much higher rates. From the late eighteenth century onwards, the British city of Manchester acquired the nickname "cottonopolis" due to the cotton industry's omnipresence within the city, and Manchester's role as the heart of the global cotton trade. Production capacity was further improved by the invention of the cotton gin by Eli Whitney in 1793. Improving technology and increasing control of world markets allowed British traders to develop a commercial chain in which raw cotton fibers were (at first) purchased from colonial plantations, processed into cotton cloth in the mills of Lancashire, and then re-exported on British ships to captive colonial markets in West Africa, India, and China (via Shanghai and Hong Kong).

    By the 1840s, India was no longer capable of supplying the vast quantities of cotton fibers needed by mechanized British factories, while shipping bulky, low-price cotton from India to Britain was time-consuming and expensive. This, coupled with the emergence of American cotton as a superior type (due to the longer, stronger fibers of the two domesticated native American species, Gossypium hirsutum and Gossypium barbadense), encouraged British traders to purchase cotton from plantations in the United States and the Caribbean. This was also much cheaper as it was produced by unpaid slaves. By the mid 19th century, "King Cotton" had become the backbone of the southern American economy. In the United States, cultivating and harvesting cotton became the leading occupation of slaves.

    During the American Civil War, American cotton exports slumped due to a Union blockade on Southern ports, also because of a strategic decision by the Confederate Government to cut exports, hoping to force Britain to recognize the Confederacy or enter the war, prompting the main purchasers of cotton, Britain and France, to turn to Egyptian cotton. British and French traders invested heavily in cotton plantations and the Egyptian government of Viceroy Isma'il took out substantial loans from European bankers and stock exchanges. After the American Civil War ended in 1865, British and French traders abandoned Egyptian cotton and returned to cheap American exports, sending Egypt into a deficit spiral that led to the country declaring bankruptcy in 1876, a key factor behind Egypt's annexation by the British Empire in 1882.

    During this time cotton cultivation in the British Empire, especially India, greatly increased to replace the lost production of the American South. Through tariffs and other restrictions the British government discouraged the production of cotton cloth in India; rather the raw fiber was sent to England for processing. The Indian patriot Mahatma Gandhi described the process:

    English people buy Indian cotton in the field, picked by Indian labor at seven cents a day, through an optional monopoly.

    This cotton is shipped on British bottoms, a three-week journey across the Indian Ocean, down the Red Sea, across the Mediterranean, through Gibraltar, across the Bay of Biscay and the Atlantic Ocean to London. One hundred per cent profit on this freight is regarded as small.

    The cotton is turned into cloth in Lancashire. You pay shilling wages instead of Indian pennies to your workers. The English worker not only has the advantage of better wages, but the steel companies of England get the profit of building the factories and machines. Wages; profits; all these are spent in England.

    The finished product is sent back to India at European shipping rates, once again on British ships. The captains, officers, sailors of these ships, whose wages must be paid, are English. The only Indians who profit are a few lascars who do the dirty work on the boats for a few cents a day.

    The cloth is finally sold back to the kings and landlords of India who got the money to buy this expensive cloth out of the poor peasants of India who worked at seven cents a day. (Fisher 1932 pp 154-156)

    In the United States, Southern cotton provided capital for the continuing development of the North. The cotton produced by enslaved African Americans not only helped the South but also enriched Northern merchants. Much of the Southern cotton was transshipped through the northern ports.

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کلمات کلیدی: Cotton - الیاف - علوم الیاف

Cotton is a natural fiber harvested from the cotton plant. Cotton is one of the oldest fibers under human cultivation, with traces of cotton over 7,000 years old recovered from archaeological sites. Cotton is also one of the most used natural fibers in existence today, with consumers from all classes and nations wearing and using cotton in a variety of applications. Thousands of ...

هر ماده ليفي شکل را نمي توان بعنوان ليف نساجي استفاده کرد،ليف نساجي داراي خصوصياتي است که در زير آنها را بررسي مي کنيم: 1- نسبت طول به قطر:اين نسبت بايد بيشتر از 100 از نظر تئوري و از نظر عملي بايد بيشتر از 1000باشد. بعنوان مثال : پنبه

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