Cotton is a soft staple fibre that grown in a form known as a boll around the seeds of the cotton plant, a shrub native to tropical and subtropical regions.
What Was "King Cotton"?
When in 1793 American inventor Eli Whitney
(1765–1825) developed the cotton gin, a machine that separates raw
cotton fibers from their seeds, he made it possible for cotton to become
the major crop of the American South, that is, "king cotton." In one
day, a single cotton gin operated by one person could clean as much
cotton as fifty slaves did in a day's time. With the gin, cotton growing
became a major industry. Just before Whitney invented the cotton gin,
British-born inventor Samuel Slater (1768–1835) built the first
successful water-powered cotton-thread spinning mill in Pawtucket, Rhode
Island. Slater's mill and the factories that produced woven cloth
increased the demand for cotton fibers. To meet the demand, growers in
the southern states of Alabama, Mississippi, Georgia, and South Carolina
stepped up cotton production. Cotton's importance to the livelihoods of
southerners earned it the nickname "king cotton."
Further Information: Gordon, John Steele. "King Cotton." American Heritage. September, 1992, pp. 18–19; Keeler, Patricia A., and Francis X. McCall, Jr. Unraveling Fibers. New York: Macmillan, 1995; Simonds, Christopher. Samuel Slater's Mill and the Industrial Revolution. Parsippany, N.J.: Silver Burdett, 1990.
Cotton
today is the most used textile fiber in the world. Its current market
share is 56 percent for all fibers used for apparel and home furnishings
and sold in the U.S. Another contribution is attributed to nonwoven
textiles and personal care items. The earliest evidence of using cotton
is from India and the date assigned to this fabric is 3000 B.C. There
were also excavations of cotton fabrics of comparable age in Southern
America. Cotton cultivation first spread from India to Egypt, China and
the South Pacific.
Cotton is a soft, staple fiber that grows in a form known as a boll around the seeds of the cotton plant, 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 derives from the Arabic (al) qutn قُطْن , which began to be used circa 1400.
Each cotton fiber is composed of concentric layers. The cuticle layer on the fiber itself is separable from the fiber and consists of wax and pectin materials.
Cotton
is a soft fibre that grows around the seeds of the cotton plant. Cotton
fibre grows in the seed pod or boll of the cotton plant. Each fibre is a
single elongated cell that is flat twisted and ribbon like with a wide
inner hollow (lumen).
Cotton
is a natural fiber that is grown in countries around the world. It is a
crop that requires adequate moisture and heat to mature and produce
quality fibers. Cotton growing tends to be in warmer climates. Cotton is
a true commodity in the world markets and supply and demand truly
affect prices of raw cotton.
Cotton fibers are mainly made up of cellulose. Cellulose does not form unless temperatures are over 70 °F (21 °C). The cotton fibers are attached to the seeds inside the boll
of the plant. There are usually six or seven seeds in a boll and up to 20,000 f ibers attached to each seed. The length of these fibers (also called staples) is the main determining factor in the quality of the cotton. In general, the longer the staple grows the higher the quality of the cotton. Staple lengths are divided into short, medium, and long
(and extra long, in some cases):
Long staple cottons are considered to be finer quality because they can be spun into finer yarns and those finer yarns can be woven in to softer, smoother, stronger, and more lustrous fabrics. Long staple cottons make stronger yarns, especially in fine yarns, as there are less fibers in a given length of yarn and the longer fibers provide more points of contact between the fibers when they are twisted together in the spinning process. Common areas that grow long staple cottons in the world would be Egypt, Sudan, the United States (Pima cottons grown in the west and southwest are long staple cottons), and Western China. The two most widely known long staple cottons are Egyptian cotton and Pima cotton. Pima cottons are grown mainly in the United States, but also in Peru, Israel, and Australia.
The fibers are sent to a textile mill where carding machines turn the fibers into cotton yarn. The yarns are woven into cloth that is comfortable and easy to wash but does wrinkle easily. Cotton fabric will shrink about 3% when washed unless pre-treated to resist shrinking.
Cotton is prized for its comfort, easy care, and affordability and is ideal for clothing, bedding, towels, and furnishings.
Cotton
was once harvested by hand, often by slave labor or tenant farmers. As
recently as 1965, over a fourth of the U.S. cotton crop was picked by
hand. Today, harvesting cotton is highly mechanized.
Harvesting machines called strippers and pickers efficiently remove the cotton, while leaving the plants undisturbed. Spindle harvester, also called a picker, has drums with spindles that pull the cotton from the boll in one or two rows at a time. Even a one row mechanical picker can do the work formerly done by 40 hand pickers.
In stripper harvesting, the stripper moves along rows of plants, passing them between revolving rollers or brushes that pull off the cotton. Strippers also pull twigs and leaves with the cotton.
Cotton gins separate the fibers, called lint, from the seeds. After ginning, the cotton goes to the bale press that packs it into 480 pound bales about the size of a large refrigerator.
From
the field, seed cotton moves to nearby gins for separation of lint and
seed. The cotton first goes through dryers to reduce moisture content
and then through cleaning equipment to remove foreign matter. These
operations facilitate processing and improve fiber quality. The cotton
is then air conveyed to gin stands where revolving circular saws pull
the lint through closely spaced ribs that prevent the seed from passing
through. The lint is removed from the saw teeth by air blasts or
rotating brushes, and then compressed into bales weighing approximately
500 pounds. Cotton is then moved to a warehouse for storage until it is
shipped to a textile mill for use.
A typical gin will process about 12 bales per hour, while some of today’s more modern gins may process as many as 60 bales an hour.
Cotton Harvest
Further Information: Gordon, John Steele. "King Cotton." American Heritage. September, 1992, pp. 18–19; Keeler, Patricia A., and Francis X. McCall, Jr. Unraveling Fibers. New York: Macmillan, 1995; Simonds, Christopher. Samuel Slater's Mill and the Industrial Revolution. Parsippany, N.J.: Silver Burdett, 1990.
Cotton
Cotton
today is the most used textile fiber in the world. Its current market
share is 56 percent for all fibers used for apparel and home furnishings
and sold in the U.S. Another contribution is attributed to nonwoven
textiles and personal care items. The earliest evidence of using cotton
is from India and the date assigned to this fabric is 3000 B.C. There
were also excavations of cotton fabrics of comparable age in Southern
America. Cotton cultivation first spread from India to Egypt, China and
the South Pacific.Cotton is a soft, staple fiber that grows in a form known as a boll around the seeds of the cotton plant, 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 derives from the Arabic (al) qutn قُطْن , which began to be used circa 1400.
Each cotton fiber is composed of concentric layers. The cuticle layer on the fiber itself is separable from the fiber and consists of wax and pectin materials.
Properties of Cotton
Properties of Cotton
Cotton
is a soft fibre that grows around the seeds of the cotton plant. Cotton
fibre grows in the seed pod or boll of the cotton plant. Each fibre is a
single elongated cell that is flat twisted and ribbon like with a wide
inner hollow (lumen).- 90% cellulose, 6% moisture and the remainder fats and impurities
- The outer surface is covered with a protective wax like coating which gives fibre an adhesive quality
Cotton fibers are mainly made up of cellulose. Cellulose does not form unless temperatures are over 70 °F (21 °C). The cotton fibers are attached to the seeds inside the boll
of the plant. There are usually six or seven seeds in a boll and up to 20,000 f ibers attached to each seed. The length of these fibers (also called staples) is the main determining factor in the quality of the cotton. In general, the longer the staple grows the higher the quality of the cotton. Staple lengths are divided into short, medium, and long
(and extra long, in some cases):
- Short staple cotton is between 3/8” to 15/16” (.95cm to 2.4cm) in length
- Medium staple cotton is between 1” to 1-1/8” (2.54cm to 2.86cm) in length
- Long staple cotton is between 1-3/16” to 2-1/2” (3cm to 6.35cm) in length
Properties of Cotton Products
- Comfortable – there are no surface characteristics of cotton that make it irritating to human skin. Cotton feels good against skin; it has a soft hand.
- Hydrophilic – cotton has a natural affinity for water – it attracts moisture away from your body.
- Moisture passes freely through cotton – aiding in evaporation and cooling
- Good Heat Conductivity – Cotton allows heat to dissipate making it a wonderful fiber to maintain a comfortable sleeping temperature.
- Strong and abrasion resistance
- The unfavorable attributes of cotton include its lack of resiliency (cotton tends to wrinkle) and its lack of luster (colors are usually dull).
Properties of Cotton Fiber
- It has 8% moisture regain
- The cellulose is arranged in a way that gives cotton unique properties of strength, durability, and absorbency
- It is fresh, crisp, comfortable, absorbent, flexible, has no pilling problems and has good resistance to alkalis
- It has poor wrinkle resistance, shrinkage, poor acid resistance, less abrasion resistance, susceptible to damage by moths and mildew, needs lots of maintenance and stains are difficult to remove
- Its fibre length ranges from ½ inches to 2inches
- It has 10%increase in strength when wet.
- It has a flat twisted tube shap
Long Staple Cotton
In general, long staple cottons are needed to spin the yarns needed in the weaving of the finer down proof cotton fabrics.Long staple cottons are considered to be finer quality because they can be spun into finer yarns and those finer yarns can be woven in to softer, smoother, stronger, and more lustrous fabrics. Long staple cottons make stronger yarns, especially in fine yarns, as there are less fibers in a given length of yarn and the longer fibers provide more points of contact between the fibers when they are twisted together in the spinning process. Common areas that grow long staple cottons in the world would be Egypt, Sudan, the United States (Pima cottons grown in the west and southwest are long staple cottons), and Western China. The two most widely known long staple cottons are Egyptian cotton and Pima cotton. Pima cottons are grown mainly in the United States, but also in Peru, Israel, and Australia.
The fibers are sent to a textile mill where carding machines turn the fibers into cotton yarn. The yarns are woven into cloth that is comfortable and easy to wash but does wrinkle easily. Cotton fabric will shrink about 3% when washed unless pre-treated to resist shrinking.
Cotton is prized for its comfort, easy care, and affordability and is ideal for clothing, bedding, towels, and furnishings.
Classing Cotton
Cotton
buyers judge cotton on the basis of samples cut from the bales. Skilled
cotton classers grade or "class" the cotton according to standards
established by the US Department of Agriculture such as cleanliness,
degree of whiteness, length of fiber, and fiber strength.
The classers pull a sample. They discard most of the cotton until just a pinch of well-aligned fibers remains. They measure the length of the fibers, referred to as staple fibers. Longer staple fibers are higher-grade cotton and are sold at higher prices. Long staples range from 1.1 inches to 1.4 inches long.
The classers pull a sample. They discard most of the cotton until just a pinch of well-aligned fibers remains. They measure the length of the fibers, referred to as staple fibers. Longer staple fibers are higher-grade cotton and are sold at higher prices. Long staples range from 1.1 inches to 1.4 inches long.
Harvesting
Cotton
was once harvested by hand, often by slave labor or tenant farmers. As
recently as 1965, over a fourth of the U.S. cotton crop was picked by
hand. Today, harvesting cotton is highly mechanized.Harvesting machines called strippers and pickers efficiently remove the cotton, while leaving the plants undisturbed. Spindle harvester, also called a picker, has drums with spindles that pull the cotton from the boll in one or two rows at a time. Even a one row mechanical picker can do the work formerly done by 40 hand pickers.
In stripper harvesting, the stripper moves along rows of plants, passing them between revolving rollers or brushes that pull off the cotton. Strippers also pull twigs and leaves with the cotton.
Cotton gins separate the fibers, called lint, from the seeds. After ginning, the cotton goes to the bale press that packs it into 480 pound bales about the size of a large refrigerator.
Cotton Ginning
From
the field, seed cotton moves to nearby gins for separation of lint and
seed. The cotton first goes through dryers to reduce moisture content
and then through cleaning equipment to remove foreign matter. These
operations facilitate processing and improve fiber quality. The cotton
is then air conveyed to gin stands where revolving circular saws pull
the lint through closely spaced ribs that prevent the seed from passing
through. The lint is removed from the saw teeth by air blasts or
rotating brushes, and then compressed into bales weighing approximately
500 pounds. Cotton is then moved to a warehouse for storage until it is
shipped to a textile mill for use.A typical gin will process about 12 bales per hour, while some of today’s more modern gins may process as many as 60 bales an hour.
Ginning Process Flowchart
Cotton Harvest
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