No other material is quite like cotton. It is the most important of all natural fibres, accounting for half of all the fibres used by the world's textile industry. Cotton has many qualities that make it the best choice for countless uses: Cotton fibres have a natural twist that makes them so suitable for spinning into a very strong yarn.
The ability of water to penetrate right to the core of the fibre makes it easy to remove dirt from the cotton garments, and creases are easily removed by ironing.
Cotton fabric is soft and comfortable to wear close to skin because of its good moisture absorption qualities.
Charges of static electricity do not build up readily on the clothes.
HISTORY OF COTTON
Nobody seems to know exactly when people first began to use cotton, but there is evidence that it was cultivated in India and Pakistan and in Mexico and Peru 5000 years ago. In these two widely separated parts of the world, cotton must have grown wild. Then people learned to cultivate cotton plants in their fields.
In Europe, wool was the only fiber used to make clothing. Then from the Far East came tales of plants that grew "wool". Traders claimed that cotton was the wool of tiny animals called Scythian lambs, that grew on the stalks of a plant. The stalks, each with a lamb as its flower, were said to bend over so the small sheep could graze on the grass around the plant. These fantastic stories were shown to be untrue when Arabs brought the cotton plant to Spain in Middle Ages.
In the fourteenth century cotton was grown in Mediterranean countries and shipped from there to mills in the Netherlands in western Europe for spinning and weaving. Until the mid eighteenth century, cotton was not manufactured in England, because the wool manufacturers there did not want it to compete with their own product. They had managed to pass a law in 1720 making the manufacture or sale of cotton cloth illegal. When the law was finally repealed in 1736, cotton mills grew in number. In the United States though, cotton mills could not be established, as the English would not allow any of the machinery to leave the country because they feared the colonies would compete with them. But a man named Samuel Slater, who had worked in a mill in England, was able to build an American cotton mill from memory in 1790.
GROWING THE COTTON
Cotton plant's leaves resemble maple leaves and flowers look very much like pink mallow flowers that grow in swampy areas. They are relatives and belong in the same plant family. Cotton is grown in about 80 countries, in a band that stretches around the world between latitudes 45 North to 30 South. For a good crop of cotton a long, sunny growing season with at least 160 frost-free days and ample water are required. Well drained, crumbly soils that can keep moisture well are the best. In most regions extra water must be supplied by irrigation. Because of it's long growing season it is best to plant early but not before the sun has warmed the soil enough.
Seedlings appear about 5 days after planting the seeds. Weeds have to be removed because they compete with seedlings for water, light and minerals and also encourage pests and diseases. The first flower buds appear after 5-6 weeks, and in another 3-5 weeks these buds become flowers.
Each flower falls after only 3 days leaving behind a small seed pot, known as the boll. Children in cotton-growing areas in the South sometimes sing this song about the flowers:
First day white, next day red,
third day from my birth - I'm dead.
Each boll contains about 30 seeds, and up to 500 000 fibres of cotton. Each fibre grows its full length in 3 weeks and for the following 4-7 weeks each fiber gets thicker as layers of cellulose build up the cell walls. While this is happening the boll matures and in about 10 weeks after flowering it splits open. The raw cotton fibres burst out to dry in the sun. As they lose water and die, each fibre collapses into what looks like a twisted ribbon. Now is time for harvesting. Most cotton is hand-picked. This is the best method of obtaining fully grown cotton because unwanted material, called "trash", like leaves and the remains of the boll are left behind. Also the cotton that is too young to harvest is left for a second and third picking. A crop can be picked over a period of two months as the bolls ripen. Countries that are wealthy and where the land is flat enough usually pick cotton with machines - cotton harvesters.
MANUFACTURING THE COTTON
After the harvested cotton has been dried and much of the trash removed, the fibres are separated from their seeds in a process called "ginning". In the past this was very time-consuming work - separating one pound of fibres by hand was considered a good day's work. In 1793, an American Inventor named Eli Whitney changed the way this was done when he invented a machine known as the cotton gin. It separated the fiber and the seeds mechanically and it was able to separate fifty pounds per day. Since then, many improvements of this machine have been made. Following separation the cotton is pressed into bales and wrapped for protection. The seeds are not wasted, and are used to make cotton seed oil and food for cattle.
The next step is "classing" to decide the quality of cotton. The "classer" judges cotton samples by hand and by eye. The value depends on the length of fibre, its colour, its feel and the amount of remaining trash. Once the quality of the bale is decided, the price is set and the cotton is taken to the market. It is sold to a local mill or to a cotton merchant who sells cotton to mills farther away or abroad.
Even though we do not grow much cotton in Canada the following processes can be done here. To turn a tightly packed bale of raw cotton with its millions of tangled fibres into a fabric needs a number of specific stages. First of all the cotton fibres have to be spun. From ancient times it was done by hand. But, in 1765, the spinning jenny was invented by an Englishman named James Hargreaves. This machine was able to spin eight to eleven threads at the same time. In 1769, Richard Arkwright, introduced a roller spinning method, which pulled and twisted the yarn and wound it on large spools in one operation.
Today, spinning is done by very sophisticated machines: the contents of several bales are fed into opening machines that open out fibres into small tufts and remove much of the remaining trash. The loose, fluffy fibres are then formed into a long sheet that is wound into a roll called a lap which is fed into a carding machine that untangles the cotton into single fibres and forms them into a long soft rope called a sliver. Several slivers are fed into a drawing machine that combines them into a single sliver that is finally drawn into a much finer strand of fibres called roving. The roving is wound onto a bobbin and drawn out to its final size on a spinning frame, the process is called "ring spinning". Here it is twisted into what is known as yarn. A more recent process called "open-end" spinning sends the sliver into a machine that twists it directly into yarn.
The best quality yarn is combed cotton which is passed through a machine that removes short fibres before spinning. This gives a much stronger, cleaner, and smoother yarn. It is also more expensive to make, since as much as one-fifth of the fibres may be removed during combing.
After the yarn is spun it is wound on special tubes ready to be dyed. Following dyeing the single strands of yarn are twisted together into various thicknesses. After that the yarn is wound on tubes of different weights ready to be sold.
As you can see the process from a seed to yarn is a long and laborious one but because of cotton's many good qualities it is well worth the effort. Popularity of cotton yarn and fabric is great and growing.
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