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you know this about Cotton?
PROPERTIES OF COTTON
No other material is quite like cotton. It is the most important of all natural
fibers,
accounting for half of all the fibers used by the world's textile industry.
Cotton has many qualities that make it the best choice for countless uses:
Cotton fibers 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 fiber 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was finally repealed in 1736, cotton mills grew in number.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 fibers of cotton. Each fiber
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 fibers 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 fibers are separated from their seeds in a process called "ginning". In the
past this was very time-consuming work - separating one pound of fibers 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 fiber, its color, 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 fibers into a
fabric needs a number of specific stages. First of all the cotton fibers 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 fibers into small tufts and remove much of the
remaining trash. The loose, fluffy fibers 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 fibers 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 fibers 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 fibers 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 fibers 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.
So we are happy to say - Cotton is
here to stay!
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