Chaptar (2.10.1) Cotton Fibres - the king of fibres

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

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 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):

• 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.

  

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

 

 Picking Cotton

 

Chaptar (2.10) Natural Cellulosic Seed Fibres

Cellulose is the substance that makes up most of a plant's cell walls. Since it is made by all plants, it is probably the most abundant organic compound on Earth.Many varieties of plant fibres exist such as hairs (cotton, kapok), fibre-sheafs of dicoltylic plants or vessel-sheafs of monocotylic plants (e.g. flax, hemp, jute and ramie), and hard fibres (sisal,henequen and coir), not to mention the large number of fibres obtained from trees. Byproducts of agricultural crops are being considered as

Seed/Fruit-hair Fibers

The seeds and fruits of plants are often attached to hairs or fibers or encased in a husk that may be fibrous. These fibers are cellulosic based and of commercial importance, especially cotton, the most important natural textile fiber.

Major Seed/Fruit-hair fibers

Cotton

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 ????? , 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.

Coir

This fiber, obtained from husks of the fruit of the coconut palm, Cocos nucifera (palm family, Arecaceae), is mainly produced in India and Sri Lanka. The fruits are broken by hand or machine, and the fiber extracted from the broken husks from which the coconut has been removed for the copra. The husks are retted in rivers, and the fiber separated by hand beating with sticks or by a decortication machine. The fibers are washed, dried, and hackled, and used in upholstery, cordage, fabrics, mats, and brushes.

Kapok

Kapok fiber is obtained from the seed pods of the kapok tree, Ceiba pentandra, of the Kapok tree family (Bombacaceae) which is indigenous to Africa and southeast Asia; the fiber is produced mainly in Java. The tree grows to a height of 35 m. The seeds are contained in capsules or pods that are picked and broken open with mallets. The fioss is dried and the fiber is separated by hand or mechanically. A nondrying oil is produced from the seeds with properties similar to cottonseed oil. The fiber is exceedingly light, with a circular cross section, thin walls, and a wide lumen. Kapok fibers are moisture resistant, buoyant, resilient, soft, and brittle, but not suitable for spinning. The traditional uses were in life jackets, sleeping bags, insulation, and upholstery; however, synthetics have replaced most of the applications as filling material and now kapok is mainly used for life preservers. Kapok-filled life preservers can support up to three times the weight of the preserver and do not become waterlogged.

Chaptar (2.9 )Properties of Vegetable/Plant/Cellulosic fibres

Chemically, cotton is the purest vegetable fibre, containing >90% cellulose with little or no lignin.

Vegetable/Cellulosic Fiber Properties

Chemically, cotton is the purest vegetable fiber, containing >90% cellulose with little or no lignin. The other fibers contain 40–75% cellulose, depending on processing. Boiled and bleached fiax and degummed ramie may contain >95% cellulose. Kenaf and jute contain higher contents of lignin, which contributes to their stiff- ness. Although the cellulose contents are fairly uniform, the other components, eg, hemicelluloses, pectins, extractives, and lignin vary widely without obvious pattern. These differences may characterize specific fibers. Except for the seed-hair fibers, the vegetable fibers of bast or leaf origins are multicelled and are used as strands.
In contrast to the bast fibers, leaf fibers are not readily broken down into their ultimate cells. The ultimate cells are composites of micro- fibrils, which, in turn, are comprised of groups of parallel cellulose chains. Bast and leaf fibers are stronger (higher tensile strength and modulus of elasticity) but lower in elongation (extensibility) than cotton. Vegetable fibers are stiffer but less tough than synthetic fibers. Kapok and coir are relatively low in strength; kapok is known for its buoyancy.

Chemical Composition of Vegetable Fibers, wt %

Fiber	Cellulose	Hemicellulose	Pectins	Lignin	Extractives
Bast Fibers
Flax	71.2	18.6	2.0	2.2	6.0
Hemp	74.9	17.9	0.9	3.7	3.1
Jute	71.5	13.4	0.2	13.1	1.8
Kenaf	63.0	18.0	-	17.0	2.0
Ramie	76.2	14.6	2.1	0.7	6.4
Leaf Fibers
Abaca	70.1	21.8	0.6	5.7	1.8
Phormium	71.3	-	-	-	-
Sisal	73.1	13.3	0.9	11.0	1.6
Seed-hair Fibers
Coir	43.0	0.1	-	45.0	-
Cotton	92.9	2.6	2.6	-	1.9
Kapok	64.0	23.0	23.0	13.0	-

 

Dimensions of Ultimate Fibers and Strands

	Ultimate fiber		Cell cross-section		Fiber strand
Fiber	Length,mm	Diameter,µm	Shape	Diameter,µm	Length,cm	Width,mm
Bast Fibers
Chinese Jute	2-6.5	7.33
Flax	4-69	8-31	Polygonal	8.8-16.1	25-120	0.04-0.62
Hemp	5-55	16	Polygonal	13.1-23.6	100-400	0.5-5
Jute	0.7-6	15-25	Polygonal-Oval	12.3-18.6	150-360
Kenaf	2-11	13-33	Cylindrical		200-400
Ramie	60-250	16-120	Hexagonal-Oval	6.2-32.4	10-180
Sunn	2-11	13-64	Irregular	13.6-24.6	108-216
Nettle	4-70	20-70		50-50
Leaf Fibers
Abaca	2-12	6-40	Oval-Round	14-20	150-360	0.01-0.28
Cantala				13.8-16.4
Caroa	2-10	3-13		3.2-8.2
Henequen	1.5-4	8.3-33.2		11.6-22.2
Istle		9.6-16		1.2-13.4	30-75
Mauritius	1.3-6	15-32	Cylindrical		124-210
Phormium	2-11	5-25	Round	10-3-12.5	150-240
Sansevieria	1-7	13-40
Sisal	0.8-7.5	8-48	Cylindrical	11-16	60-120	0.1-0.5
Seed-hair Fibers
Coir	0.2-1	6.24				1
Cotton	10-50	12-25	Circular Elliptical		1.5-5.6	0.012-0.025
Kapok	15-30	10-30	Round		1.5-3	0.03-0.036
Other Fibers
Broom Root			Others		25-40

  

Mechanical Properties of Vegetable Fibers

Fiber	Fineness km/kg	Tensile Strength, km	Elongation %	Modulus of Elasticity, N/tex	Modulus of repture, mN/tex
Bast (soft) fibers
Flax		2470	2-3	18-20	8-9
Hemp	139	38-62	1-6	18-22	6-9
Jute	489	25-53	1.5	17-18	2.7-3
Kenaf	180	24	2.7
Ramie		32-67	4.0	14-16	11
Urena	342	16	1.9
Leaf (hard) fibers
Abaca	32	32-69	2-4.5		6
Cantala	58	30
Henequen	32	20-42	3.5-5
Istle	34	22-27	4.8
Phormium	38	26
Sansevieria	118	43	4.0
Sisal	40	36-45	2-3	25-26	7-8
Seed-har fibers
Coir	18	16	4.3	16
Kapok	16-30	1.2	13	10

Chaptar (2.8) Natural Cellulose Fibres

 

 Natures own fibres

Cellulose is a fibrous material of plant origin and the basis of all natural and man-made cellulosic fibres. The natural cellulosic fibres include cotton, flax, hemp, jute, and ramie. Cellulose is a polymeric sugar polysaccharide) made up of repeating 1,4-8-an hydro glucose units connected to each other by 8-ether linkages. Strong intermolecular forces between chains, coupled with the high linearity of the cellulose molecule, account for the crystalline nature of cellulosic fibres.

Cellulosic Fibers

The natural fibers are vegetable, animal, or mineral in origin. Vegetable fibers, as the name implies, are derived from plants. The principal chemical component in plants is cellulose, and therefore they are also referred to as cellulosic fibers. The fibers are usually bound by a natural phenolic polymer, lignin, which also is frequently present in the cell wall of the fiber; thus vegetable fibers are also often referred to as lignocellulosic fibers, except for cotton, which does not contain lignin.
Cellulose is a fibrous material of plant Origin and the basis of all natural and man-made cellulosic fibers. The natural cellulosic fibers include cotton, flax, hemp, jute, and ramie. The major man-made cellulosic fiber is rayon, a fiber produced by regeneration of dissolved forms of cellulose.
Cellulose is a polymeric sugar (polysaccharide) made up of repeating 1,4-8-an hydroglucose units connected to each other by 8-ether linkages.
The long 1inear chains of cellulose permit the hydroxyl functional groups on each anhydro glucose unit to interact with hydroxyl groups on adjacent chains through hydrogen bonding and van der Waal s forces. These strong intermolecular forces between chains, coupled with the high linearity of the cellulose molecule, account for the crystalline nature of cellulosic fibers.

Classification of Vegetable Fibers

Vegetable fibers are classified according to their source in plants as follows: (1) the bast or stem fibers, which form the fibrous bundles in the inner bark (phloem or bast) of the plant stems, are often referred to as soft fibers for textile use; (2) the leaf fibers, which run lengthwise through the leaves of monocotyledonous plants, are also referred to as hard fibers; and (3) the seed-hair fibers, the source of cotton, which is the most important vegetable fiber. There are >250,000 species of higher plants; however, only a very limited number of species have been exploited for commercial uses (<0.1%).
The fibers in bast and leaf fiber plants are integral with the plant structure, providing strength and support. In bast fiber plants, the fibers are next to the outer bark in the bast or phloem and serve to strengthen the stems of these reed-like plants. The fibers are in strands running the length of the stem or between joints. To separate the strands, the natural gum binding them must be removed. This operation is called retting (controlled rotting). For most uses, particularly for textiles, this long composite-type strand fiber is used directly; however, when such fiber strands are pulped by chemical means the strand is broken down into much shorter and finer fibers, the ultimate fibers.
The long leaf-fibers contribute strength to the leaves of certain nonwoody, monocotyledonous plants. They extend longitudinally the full length of the leaf and are buried in tissues of a parenchymatous nature. The fibers found nearest the leaf surface are the strongest. The fibers are separated from the pulp tissue by scraping because there is little bonding between fiber and pulp; this operation is called decortication. Leaf fiber strands are also multicelled in structure. Ancient humans used cordage in fishing, trapping, and transport, and in fabrics for clothing. Rope and cord making started in Paleolithic times, as seen in cave drawings. Rope, cords, and fabrics were made from reeds and grasses in ancient Egypt (400 BC). Ropes, boats, sails, and mats were made from palm leaf fibers and papyrus stalks and writing surfaces, known as papyrus, from the pith section. Jute, fiax, ramie, sedges, rushes, and reeds have long been used for fabrics and baskets. Jute was cultivated in India in ancient times and used for spinning and weaving. The first true paper is believed to have been made in southeastern China in the second century AD from old rags (bast fibers) of hemp and ramie and later from the bast fiber of the mulberry tree.
World markets for vegetable fibers have been steadily declining in recent years, mainly as a result of substitution with synthetic materials. Jute has traditionally been one of the principal bast fibers (tonnage basis) sold on the world market; however, the precipitous decline in jute exports by India indicate the decreasing market demand for this fiber that has been vitally important to the economies of India (West Bengal), Bangladesh, and Pakistan.

  

Seed Fibers

	Cotton is the most commonly used natural cellulosic fiber. Cotton fibers grow from the seeds in the boll (seedpod). Each boll contains seven or eight seeds, and each seed may have up to 20,000 fibers growing from it.
	Coir is from the fibrous mass between the outer shell and husk of coconuts.  It is a stiff fiber.  It is usually used to make highly durable indoor and outdoor mats, rugs, and tiles.
	Kapok fiber is from the seed of the Java or Indian kapok tree.  The fiber is soft, lightweight, and hollow.  It breaks down easily and it is difficult to spin into yarns. It is used as fiberfill and as the stuffing for pillows. It used to be used as a stuffing for lifejackets and the mattresses on cruise ships because it is very buoyant.

 

Bast Fibers

	Flax is one of the oldest textile fibers, but its use has declined since the invention of power spinning for cotton. Flax fabric is linen, although the word linen is now often used to refer to table, bed, and bath fabrics made from other materials
	Ramie fibers are 4 to 6 inches long. The fibers are whiter and softer than flax. Ramie does not retain dyes well unless it is dry-cleaned. Ramie is strong for a natural fiber, but it lacks resiliency, elasticity, and elongation potential. It is resistant to mildew, insects, and shrinkage. It is used for apparel, window treatments, ropes, paper, and table and bed linens
	Hemp is similar to flax. The fibers range in length from 3 to 15 feet. Hemp production is illegal in the U.S. Hemp has a low environmental impact; it does not require pesticides. It produces 250% more fiber than cotton and 600% more fiber than flax on the same amount of land. Hemp plants can be used to extract zinc and mercury pollutants from soil. Hemp is used for ropes, apparel, and paper. Potheads are willing to pay inflated prices for hemp apparel because it is related to the marijuana plant
	Jute is one of the cheapest textile fibers, and one of the weakest cellulosic fibers. Jute has poor elasticity, elongation, sunlight resistance, mildew resistance, and colorfastness. It is used to produce sugar and coffee bagging, carpet backing, rope, and wall coverings. Burlap is made from jute.

  

Leaf Fibers

	Piña fibers are from the leaves of the pineapple plant. It is used to make lightweight, sheer, stiff fabrics for apparel, bags, and table linens.  It is also used to make mats.
	Abaca is from a member of the banana tree family. The fibers are coarse and very long (up to 15 feet). It is a strong, durable, and flexible fiber used for ropes, floor mats, table linens, apparel, and wicker furniture.

  

Natural Cellulosic Fiber Characteristics

Fiber	Properties
Ramie Ramie is one of the oldest fibre crops, having been used for at least six thousand years. It is also known as china grass.	Ramie requires chemical processing to de-gum the fibre. It is fine absorbent, quick drying fibre, is slightly stiff and possesses high natural lustre. Its plant height is 2.5m and its strength is eight times more than cotton
Hemp Depending on the processing used to remove the fiber from the stem, the hemp naturally may be creamy white, brown, gray, black or green.	It is yellowish brown fibre Hemp fibers can be 3 to 15 feet long, running the length of the plant Characteristics of hemp fibre are its superior strength and durability, resistance to ultraviolet light and mold, comfort and good absorbancy
Jute Jute is one of the cheapest natural fibres and is second only to cotton in amount produced and variety of uses. Jute fibres are composed primarily of the plant materials cellulose and lignin.	Jute is a long, soft, shiny vegetable fibre that can be spun into coarse, strong threads. It is thus a ligno -cellulosic fibre that is partially a textile fibre and partially wood. The plant grows up to a height of 2.5m and its fibre length is about 2m. It is generally used in geo textiles. It has a good resistance to micro organisms and insects. It has low wet strength, low elongation and inexpensive to produce
Coir Fibre mechanically extracted from dry mature coconut husk after soaking.	It is long, hard and strong fibre but with lower softness, lower water absorption capacity, and shorter life than long retted fibre.
Kapok Kapok fiber is a silky cotton-like substance that surrounds the seeds in the pods of the ceiba tree.	It can support as much as 30 times its own weight in water and loses only 10 percent of buoyancy over a 30-day period. It is eight times lighter than cotton It is extremely used as a thermal-insulator. It is also lightweight, non-allergic, non-toxic, resistant to rot and odorless. Since it is inelastic and too fragile, it can't be spun. It has outstanding characteristics of lightness, impermeability, thermal-isolation and eco- naturality.

Natural Fibres (excerpt)

Natural fibre 

 

 

Chaptar(2.7) Natural Fibres

 

Fibres from the nature

All fibres which come from natural sources (animals, plants, etc.) and do not require fibre formation or reformation are classed as natural fibres. The natural fibres are vegetable, animal, or mineral in origin. Some of the natural fibres like vegetable fibres are obtained from the various parts of the plants. They are provided by nature in ready-made form. It include the protein fibres such as wool and silk, the cellulose fibres such as cotton and linen, and the mineral fibre asbestos.

Natural Fibers

Textile fibers are normally broken down into two main classes, natural and man-made fibers. All fibers which come from natural sources (animals, plants, etc.) and do not require fiber formation or reformation are classed as natural fibers.
Natural plant and animal fibres have provided the raw materials to meet our fibre needs. No matter which climatic zone humans settled, they were able to utilize the fibres of native species to make products such as clothes, buildings and cordage. The use of composite materials dates from centuries ago and it all started with natural fibres.

Natural fibre is any hair like raw material directly obtainable from animals, vegetables or mineral source and convertible into nonwoven fabrics such as felt or after spinning into yarns or woven cloth.

Natural fibres from vegetable fibres are obtained from the various parts of the plants. These fibres are classified into three categories depending on the part of the plant from which they are extracted. Those three categories are bast or stem fibres (jute, mesta, banana etc.), leaf fibres (sisal, pineapple, screw pine etc.) seed fibres (cotton, coir, old palm etc.). Many of the plant fibres such as coir, sisal, jute, banana, pineapple and hemp find applications as a resource for industrial materials. Properties of natural fibres depend mainly on the nature of the plant, locality in which it is grown, age of the plant, and the extraction method used.
A natural fibre also may be further defined as a agglomeration of cells in which the diameter is negligible in comparison with the length. In some applications, natural fibres are replacing glass fibres in reinforced polymers, where the tensile strength of the fibre is not as important as the specific stiffness. Natural fibre reinforced polymers are generally restricted for use in non-structural products.
In contrast, fibers from natural sources are provided by nature in ready-made form.
Natural fibers include the protein fibers such as wool and silk, the cellulose fibers such as cotton and linen, and the mineral fiber asbestos.
Plant fibers can be further on classified as:

• Fibre occurring on the seed (raw cotton, java cotton)
• Phloem fiber (flax, ramie, hemp, jute)
• Tendon fibre from stem or leaves (manila  hemp, sisal hemp etc)
• Fibre occurring around the trunk (hemp palm)
• Fibre of fruit/ nut shells (coconut fibre – Coir)

Cotton and Linen (made from Flax pant) are the most important among them.

Advantages and Disadvantages of Natural Fibres

Advantages

Disadvantages

Producible with low investment at low cost, which makes the material an interesting product for low-wage countries. Thermal recycling is possible, where glass causes problems in combustion furnaces. Low specific weight, which results in a higher specific strength and stiffness than glass. This is a benefit especially in parts designed for bending stiffness It is a renewable resource, the production requires little energy, CO2 is used while oxygen is given back to the environment.

Price can fluctuate by harvest results or agricultural politics. Lower durability, fibre treatments can improve this considerably. Moisture absorption, which causes swelling of the fibres. Lower strength properties, particularly its impact strength.

  

Natural Fibers, Quilts & the Textile Arts

 

Chaptar (2.6) Ginning

What does Ginning mean?

The process of removing the seeds from the cotton.

Rawr Denim explains Ginning

Ginning is the process of removing the seeds and debris from cotton. The term comes from the cotton gin, invented by Eli Whitney in 1794. In modern ginning, the cotton is first dried to remove moisture, then cleaned to remove any burs, stems, leaves, or other foreign matter. A series of rotating saws with teeth then remove the fibers from the seeds. Afterwards, the cotton fibers are compressed into 500-pound bales to be sent to textiles mills.

Additional Resources

Here is the industrial process of ginning:

Textile Yarns processing technology

ssing technology

Ginning: The process of separating the seeds from the cotton fibers is known as ginning.
There are 3 types of ginning processes. They are:

1. Knife roller gin for Indian and Pakistani cotton
2. Mscarthy roller gin for Long staple cotton
3. Saw gin used for American, West African, Pakistani cotton

Points to be considered for fiber during processing:

Main Factors

• Length
• Fineness
• MaturityUniformityTrash Content

Other Properties

• Pliability
• Cohesiveness
• Tensile Strength

 Cotton Ginning Process Video Part-1

 

 

Cotton Ginning Process video part 2 

 

Chaptar (2.5) Timeline of Man made Fibers

A useful filament was not produced until the last part of the 19th century, when Swann and de Chardonnet extruded a solution of cellulose nitrate (collodion) through small holes (spinnerets). These pioneer manmade fibres were replaced by rayon fibres which were spun from an alkaline cellulose xanthate solution (viscose), which were in turn supplemented by cellulose acetate and many synthetic fibres.

Year	Description
1664	English naturalist Robert Hooke first suggested the possibility of producing a fiber that would be “if not fully as good, nay better” than silk.
1855	The first patent for “artificial silk” was granted in England in 1855 to a Swiss chemist named Audemars. He dissolved the fibrous inner bark of a mulberry tree, chemically modifying it to produce cellulose. He formed threads by dipping needles into this solution and drawing them out - but it never occurred to him to emulate the silkworm by extruding the cellulosic liquid through a small hole.
Early 1880's	Sir Joseph W. Swan, an English chemist and electrician, inspired by Thomas Edison's new incandescent electric lamp. He experimented with forcing a liquid similar to Audemars solution through fine holes into a coagulating bath. His fibers worked like carbon filament, and they found early use in Edison's invention. In 1885 he exhibited in London some fabrics crocheted by his wife from his new fiber, but he focused on electric lamps and abandoned work on textiles.
1889	French chemist Count Hilaire deChardonnet displayed fabric “artificial silk” in the Paris Exhibition.
1890	Count Hilarie deChardonnet built the first commercial rayon plant at Besancon, France and secured his fame as the father of the rayon industry.
1893	Arthur D. Little of Boston, invented cellulosic acetate and developed it as a film.
1910	The American Viscose Company, formed by Samuel Courtaulds and Co., Ltd., began production of rayon.
By 1910	Camille and Henry Dreyfus were making acetate motion picture film and toilet articles in Basel, Switzerland. During World War I, they built a plant in England to produce cellulose acetate dope for airplane wings and other commercial products. Upon entering the War, the United States government invited the Dreyfus brothers to build a plant in Maryland to make the product for American warplanes.
1924	First commercial textile uses for acetate in fiber form were developed by the Celanese Company.
Mid-1920's	Textile manufacturers could purchase the rayon and acetate fibers for half the price of raw silk, and so began manufactured fibers' gradual conquest of the American fiber market. This modest start in the 1920's grew to nearly 70% of the national market for fiber by the last decade of the century.
1931	American chemist Wallace Carothers reported on research carried out in the laboratories of the DuPont Company on “giant” molecules called polymers. He focused his work on a fiber referred to simply as “66,” a number derived from its molecular structure. Nylon, the “miracle fiber,” was born. The Chemical Heritage Foundation is currently featuring an exhibit on the history of nylon.
1938	Paul Schlack of the I.G. Farben Company in Germany, polymerized caprolactam and created a different form of the polymer, identified simply as nylon “6.” Nylon's advent created a revolution in the fiber industry. Rayon and acetate had been derived from plant cellulose, but nylon was synthesized completely from petrochemicals. It established the basis for the ensuing discovery of an entire new world of manufactured fibers.
1939	Vinyon was first produced in 1939 by American Viscose, now FMC Corporation.
1939	Vinyon was first produced in 1939 by American Viscose, now FMC Corporation.
1939	DuPont began commercial production of nylon. The first experimental testing used nylon as sewing thread, in parachute fabric, and in women's hosiery. Nylon stockings were shown in February 1939 at the San Francisco Exposition and the most exciting fashion innovation of the age was underway. American women had only a sampling of the beauty and durability of their first pairs of nylon hose when their romance with the new fabric was cut short when the United States entered World War II.
1941	The War Production Board allocated all production of nylon for military use. During the War, nylon replaced Asian silk in parachutes. It also found use in tires, tents, ropes, ponchos, and other military supplies, and even was used in the production of a high-grade paper for U.S. currency. At the outset of the War, cotton was king of fibers, accounting for more than 80% of all fibers used. Manufactured and wool fibers shared the remaining 20%.
August 1945	By the end of the war cotton stood at 75% of the fiber market. Manufactured fibers had risen to 15%. After the war, GI's came home,families were reunited, industrial America gathered its peacetime forces, and economic growth surged. The conversion of nylon production to civilian uses started and when the first small quantities of postwar nylon stockings were advertised, thousands of frenzied women lined up at New York department stores to buy. In the immediate post-war period, most nylon production was used to satisfy this enormous pent up demand for hosiery.
Late 1940's	Nylon was also being used in carpeting and automobile upholstery. At the same time, three new generic manufactured fibers started production. Dow Badische Company (today, BASF Corporation) introduced metalized fibers; Union Carbide Corporation developed modacrylic fiber; and Hercules, Inc. added olefin fiber.
By the 1950's	The industry was supplying more than 20% of the fiber needs of textile mills. A new fiber, “acrylic,” was added to the list of generic names, as DuPont began production of this wool-like product. Meanwhile, polyester, first examined as part of the Wallace Carothers early research, was attracting new interest at the Calico Printers Association in Great Britain. There, J. T. Dickson and J. R. Whinfield produced a polyester fiber by condensation polymerization of ethylene glycol with terephthalic acid. DuPont subsequently acquired the patent rights for the United States and Imperial Chemical Industries for the rest of the world. A host of other producers soon joined in.
Summer 1952	“Wash-and-wear” was coined to describe a new blend of cotton and acrylic. The term eventually was applied to a wide variety of manufactured fiber blends. Commercial production of polyester fiber transformed the wash-and-wear novelty into a revolution in textile product performance.
1953	Polyester's commercialization was accompanied by the introduction of triacetate. The majority of the 20th century's basic manufactured fibers now had been discovered, and the industry's engineers turned to refining their chemical and physical properties to extend their use across the American economy.
Early 1960's	Manufactured fiber accounted for nearly 30% of American textile mill consumption.
By 1965	The manufactured fiber industry was providing over 40% of the nation's fiber needs.
1960's	Manufactured fiber production accelerated as it was spurred on by continuous fiber innovation. The revolutionary new fibers were modified to offer greater comfort, provide flame resistance, reduce clinging, release soil, achieve greater whiteness, special dullness or luster, easier dyeability, and better blending qualities. New fiber shapes and thicknesses were introduced to meet special needs. Spandex, a stretchable fiber; aramid, a high-temperature-resistant polyamide; and para-aramid, with outstanding strength-to-eight properties, were introduced into the marketplace. Consumers bought more and more clothing made with polyester. Clotheslines were replaced by electric dryers, and the “wash and wear” garments they dried emerged wrinkle free. Ironing began to shrink away on the daily list of household chores. Fabrics became more durable and color more permanent. New dyeing effects were being achieved and shape-retaining knits offered new comfort and style.
Late 1960's	One dramatic new set of uses for manufactured fibers came with the establishment of the U.S. space program. The industry provided special fiber for uses ranging from clothing for the astronauts to spaceship nose cones. When Neil Armstrong took “One small step for man, one giant leap for mankind,” on the moon on July 20, 1969, his lunar space suit included multi-layers of nylon and aramid fabrics. The flag he planted was made of nylon. Today, the exhaust nozzles of the two large booster rockets that lift the space shuttle into orbit contain 30,000 pounds of carbonized rayon. Carbon fiber composites are used in as structural components in the latest commercial aircraft, adding strength and lowering weight and fuel costs.
Early 1970's	A wave of consumer protection demands emerged, most notably one for a mandated Federal flammability standard for children's sleepwear. The manufactured fiber industry spent $20 million on flammability research and development in 1972 and 1973, and manufactured fiber fabrics became predominant in this market. Flammability standards were also issued for carpet and other products. In the U.S. carpet market, 99% of all surface fibers are now manufactured fibers.
Late 1973	When the U.S. was struck by a severe energy crisis, the manufactured fiber industry reduced the energy required to produce a pound of fiber by 26%. By then, the industry was using but 1% of the Nation's petroleum supply to provide two-thirds of all fibers used by American textile mills. Innovation is the hallmark of the manufactured fiber industry. Fibers more numerous and diverse than any found in nature, are now routinely created in the industry's laboratories.
1990's	Nylon variants, polyester, and olefin are used to produce carpets that easily can be rinsed clean even 24 hours after they've been stained. Stretchable spandex and machine-washable, silk-like polyesters occupy solid places in the U.S. apparel market. The finest microfibers are remaking the world of fashion.
Late 1990’s	Increased environmental awareness further encourages manufacturers to become green manufacturers, reducing energy consumption, cleaning up or eliminating air and water pollution, and recycling production supplies and finding environmentally safe uses for fabric waste.
2001	Cargill Dow introduces the first completely renewable fiber made of plant dextrose from cornstarch, polylactide (PLA) and markets it as InGeo. It competes in durability with the petrochemicals and can be disposed of safely as completely biodegradable end use products. PLA has application in interior design materials and carpeting, apparel, packaging, and industry.
Today	Fiber research and improvement continues. As they always have, manufactured fibers continue to mean, “life made better.”