FIBREFIBRE

FiberFiber is a rope or string used as a component of composite is a rope or string used as a component of composite materials into sheets to make products such as paper or materials into sheets to make products such as paper or felt. Fibers are often used in the manufacture of other felt. Fibers are often used in the manufacture of other materials. The strongest engineering materials are materials. The strongest engineering materials are generally made as fibers, for example carbon fiber and generally made as fibers, for example carbon fiber and Ultra-high-molecular-weight polyethylene. A fibre is a Ultra-high-molecular-weight polyethylene. A fibre is a material which is several 100 times as long as as it’s thick.material which is several 100 times as long as as it’s thick.

Synthetic fibers can often be produced very cheaply and in Synthetic fibers can often be produced very cheaply and in large amounts compared to natural fibers, but for clothing large amounts compared to natural fibers, but for clothing natural fibers can give some benefits, such as comfort, over natural fibers can give some benefits, such as comfort, over their synthetic counterparts.their synthetic counterparts.

FIBRE CONTENTSFIBRE CONTENTS

1 Textile fiber1 Textile fiber 2 Natural fibers2 Natural fibers 3 Synthetic fibers3 Synthetic fibers

• 3.1 Metallic fibers3.1 Metallic fibers• 3.2 Carbon Fiber3.2 Carbon Fiber• 3.3 Silicon carbide fiber3.3 Silicon carbide fiber• 3.4 Fiberglass3.4 Fiberglass• 3.5 Mineral fibers3.5 Mineral fibers• 3.6 Cellulose fibers3.6 Cellulose fibers• 3.7 Polymer fibers3.7 Polymer fibers• 3.8 Microfibers3.8 Microfibers

1. Textile fiber:1. Textile fiber: -A unit in which many complicated textile -A unit in which many complicated textile

structures are built up is said to be textile structures are built up is said to be textile fiber.fiber.

2. Natural fibers:2. Natural fibers: -Natural fibers include those produced by -Natural fibers include those produced by

plants, animals, and geological processes. plants, animals, and geological processes. They are biodegradable over time. They They are biodegradable over time. They can be classified according to their origin:can be classified according to their origin:

- Vegetable fibers are generally based on arrangements of - Vegetable fibers are generally based on arrangements of cellulose, often with lignin: examples include cellulose, often with lignin: examples include cottoncotton, , hemp, jute, flax, ramie, sisal and bagasse. Plant fibers are hemp, jute, flax, ramie, sisal and bagasse. Plant fibers are employed in the manufacture of paper and employed in the manufacture of paper and textile textile (cloth).(cloth).

- Wood fiber, distinguished from vegetable fiber, is from tree - Wood fiber, distinguished from vegetable fiber, is from tree sources. Forms include groundwood, thermomechanical sources. Forms include groundwood, thermomechanical pulp (TMP) and bleached or unbleached kraft or sulfite pulp (TMP) and bleached or unbleached kraft or sulfite pulps. Kraft and sulfite, also called sulphite, refer to the pulps. Kraft and sulfite, also called sulphite, refer to the type of pulping process used to remove the lignin bonding type of pulping process used to remove the lignin bonding the original wood structure, thus freeing the fibers for use the original wood structure, thus freeing the fibers for use in paper and engineered wood products such as fiberboard.in paper and engineered wood products such as fiberboard.

- Animal fibers consist largely of particular Animal fibers consist largely of particular proteins. Instances are silkworm silk, spider silk, proteins. Instances are silkworm silk, spider silk, sinew, catgut, wool, sea silk and hair such as sinew, catgut, wool, sea silk and hair such as cashmere wool, mohair and angora, fur such as cashmere wool, mohair and angora, fur such as sheepskin, rabbit, mink, fox, beaver, etc.sheepskin, rabbit, mink, fox, beaver, etc.

- Mineral fibers include the asbestos group. - Mineral fibers include the asbestos group. Asbestos is the only naturally occurring long Asbestos is the only naturally occurring long mineral fiber. Six minerals have been classified as mineral fiber. Six minerals have been classified as "asbestos" including chrysotile of the serpentine "asbestos" including chrysotile of the serpentine class and those belonging to the amphibole class: class and those belonging to the amphibole class: amosite, crocidolite, tremolite, anthophyllite and amosite, crocidolite, tremolite, anthophyllite and actinolite. Short, fiber-like minerals include actinolite. Short, fiber-like minerals include wollastonite and palygorskite.wollastonite and palygorskite.

3. Synthetic fibers3. Synthetic fibers

- Synthetic generally come from synthetic materials such as - Synthetic generally come from synthetic materials such as petrochemicals but some types of synthetic fibers are petrochemicals but some types of synthetic fibers are manufactured from natural cellulose, including rayon, manufactured from natural cellulose, including rayon, modal, and Lyocell. Cellulose-based fibers are of two types, modal, and Lyocell. Cellulose-based fibers are of two types, regenerated or pure cellulose such as from the cupro-regenerated or pure cellulose such as from the cupro-ammonium process and modified cellulose such as the ammonium process and modified cellulose such as the cellulose acetates.cellulose acetates.

- Fiber classification in reinforced plastics falls into two - Fiber classification in reinforced plastics falls into two classes: (i) short fibers, also known as discontinuous classes: (i) short fibers, also known as discontinuous fibers, with a general aspect ratio (defined as the ratio of fibers, with a general aspect ratio (defined as the ratio of fiber length to diameter) between 20 to 60, andfiber length to diameter) between 20 to 60, and

(ii) long fibers, also known as continuous fibers, the general (ii) long fibers, also known as continuous fibers, the general aspect ratio is between 200 to 500.aspect ratio is between 200 to 500.

* Metallic fibers* Metallic fibers- Metallic fibers can be drawn from ductile - Metallic fibers can be drawn from ductile

metals such as copper, gold or silver and metals such as copper, gold or silver and extruded or deposited from more brittle extruded or deposited from more brittle ones, such as nickel, aluminum or iron. ones, such as nickel, aluminum or iron. See also Stainless steel fibers.See also Stainless steel fibers.

* Carbon Fiber* Carbon Fiber- Carbon fibers are often based on oxydized - Carbon fibers are often based on oxydized

and via pyrolysis carbonized polymers like and via pyrolysis carbonized polymers like PAN, but the end product is almost pure PAN, but the end product is almost pure carbon.carbon.

* Silicon carbide fiber* Silicon carbide fiber- Silicon carbide fibers, where the basic - Silicon carbide fibers, where the basic

polymers are not hydrocarbons but polymers are not hydrocarbons but polymers, where about 50% of the carbon polymers, where about 50% of the carbon atoms are replaced by silicon atoms, so-atoms are replaced by silicon atoms, so-called poly-carbo-silanes. The pyrolysis called poly-carbo-silanes. The pyrolysis yields an amorphous silicon carbide, yields an amorphous silicon carbide, including mostly other elements like including mostly other elements like oxygen, titanium, or aluminium, but with oxygen, titanium, or aluminium, but with mechanical properties very similar to mechanical properties very similar to those of carbon fibers.those of carbon fibers.

* Fiberglass* Fiberglass- Fiberglass, made from specific glass, and optical - Fiberglass, made from specific glass, and optical

fiber, made from purified natural quartz, are also fiber, made from purified natural quartz, are also man-made fibers that come from natural raw man-made fibers that come from natural raw materials, silica fiber, made from sodium silicate materials, silica fiber, made from sodium silicate (water glass) and basalt fiber made from melted (water glass) and basalt fiber made from melted basalt.basalt.

* Mineral fibers* Mineral fibers- Mineral fibers can be particularly strong because - Mineral fibers can be particularly strong because

they are formed with a low number of surface they are formed with a low number of surface defects, Asbestos is a common one.defects, Asbestos is a common one.

* Cellulose fibers* Cellulose fibers

- Cellulose fibers are a subset of man-- Cellulose fibers are a subset of man-made fibers, regenerated from made fibers, regenerated from natural cellulose. The cellulose natural cellulose. The cellulose comes from various sources. Modal is comes from various sources. Modal is made from beech trees, bamboo made from beech trees, bamboo fiber is a cellulose fiber made from fiber is a cellulose fiber made from bamboo, seacell is made from bamboo, seacell is made from seaweed.seaweed.

• Polymer fibersPolymer fibers

- Polymer fibers are a subset of man-made fibers, which are based on - Polymer fibers are a subset of man-made fibers, which are based on synthetic chemicals (often from petrochemical sources) rather than arising synthetic chemicals (often from petrochemical sources) rather than arising from natural materials by a purely physical process. These fibers are made from natural materials by a purely physical process. These fibers are made from: from: • polyamide nylonpolyamide nylon• PET or PBT polyesterPET or PBT polyester• phenol-formaldehyde (PF)phenol-formaldehyde (PF)• polyvinyl alcohol fiber (PVA) vinylonpolyvinyl alcohol fiber (PVA) vinylon• polyvinyl chloride fiber (PVC) vinyonpolyvinyl chloride fiber (PVC) vinyon• polyolefins (PP and PE) olefin fiberpolyolefins (PP and PE) olefin fiber• acrylic polyesters, pure polyester PAN fibers are used to make carbon fiber .acrylic polyesters, pure polyester PAN fibers are used to make carbon fiber .• aromatic polyamids (aramids) such as Twaron, Kevlar and Nomex. aromatic polyamids (aramids) such as Twaron, Kevlar and Nomex. • polyethylene (PE)polyethylene (PE)• Elastomers can even be used, e.g. spandex Elastomers can even be used, e.g. spandex • polyurethane fiberpolyurethane fiber

• MicrofibersMicrofibers- Microfibers in textiles refer to sub-denier fiber - Microfibers in textiles refer to sub-denier fiber

(such as polyester drawn to 0.5 dn). Denier and (such as polyester drawn to 0.5 dn). Denier and Tex are two measurements of fiber yield based on Tex are two measurements of fiber yield based on weight and length. If the fiber density is known weight and length. If the fiber density is known you also have a fiber diameter, otherwise it is you also have a fiber diameter, otherwise it is simpler to measure diameters in micrometers. simpler to measure diameters in micrometers. Microfibers in technical fibers refer to ultra fine Microfibers in technical fibers refer to ultra fine fibers (glass or meltblown thermoplastics) often fibers (glass or meltblown thermoplastics) often used in filtration. used in filtration.

- Very short and/or irregular fibers have been called - Very short and/or irregular fibers have been called fibrils. Natural cellulose, such as cotton or fibrils. Natural cellulose, such as cotton or bleached kraft, show smaller fibrils jutting out bleached kraft, show smaller fibrils jutting out and away from the main fiber structure.and away from the main fiber structure.

Major properties of fiberMajor properties of fiber::

1. Mechanical properties: 1. Mechanical properties: - Abrasion resistance- Abrasion resistance- Flexibility- Flexibility- Stiffness.Stiffness.

2. Absorption properties: It’s a measure of quality of 2. Absorption properties: It’s a measure of quality of water vapors, liquid water etc.water vapors, liquid water etc.

3. Thermal properties: the behavior of textile in the 3. Thermal properties: the behavior of textile in the presence of heat or exposed to a flame.presence of heat or exposed to a flame.

COTTON FIBERSCOTTON FIBERS

INTRODUCTIONINTRODUCTION

Cotton today is the most used textile fiber in the world. Its Cotton today is the most used textile fiber in the world. Its current market share is 56 percent for all fibers used for current market share is 56 percent for all fibers used for apparel and home furnishings and sold in the U.S. Another apparel and home furnishings and sold in the U.S. Another contribution is attributed to nonwoven textiles and personal contribution is attributed to nonwoven textiles and personal care items. It is generally recognized that most consumers care items. It is generally recognized that most consumers prefer cotton personal care items to those containing prefer cotton personal care items to those containing synthetic fibers. World textile fiber consumption in 1998 synthetic fibers. World textile fiber consumption in 1998 was approximately 45 million tons. Of this total, cotton was approximately 45 million tons. Of this total, cotton represented approximately 20 million tons. The earliest represented approximately 20 million tons. The earliest evidence of using cotton is from India and the date evidence of using cotton is from India and the date assigned to this fabric is 3000 B.C. assigned to this fabric is 3000 B.C.

There were also excavations of cotton fabrics of There were also excavations of cotton fabrics of comparable age in Southern America. Cotton comparable age in Southern America. Cotton cultivation first spread from India to Egypt, China cultivation first spread from India to Egypt, China and the South Pacific. Even though cotton fiber and the South Pacific. Even though cotton fiber had been known already in Southern America, the had been known already in Southern America, the large-scale cotton cultivation in Northern America large-scale cotton cultivation in Northern America began in the 16th century with the arrival of began in the 16th century with the arrival of colonists to southern parts of today's United colonists to southern parts of today's United States. The largest rise in cotton production is States. The largest rise in cotton production is connected with the invention of the saw-tooth connected with the invention of the saw-tooth cotton gin by Eli Whitney in 1793. With this new cotton gin by Eli Whitney in 1793. With this new technology, it was possible to produce more technology, it was possible to produce more cotton fiber, which resulted in big changes in the cotton fiber, which resulted in big changes in the spinning and weaving industry, especially in spinning and weaving industry, especially in England. England.

COTTON CONSUMPTION COTTON CONSUMPTION AND PRODUCTION IN AND PRODUCTION IN MILLION TONS IN YEAR MILLION TONS IN YEAR 2012 :2012 :

COUNTRIES PRODUCTION CONSUMPTION

US 38 1.7

India 2.5 3

Pakistan 1.8 1.9

Turkey 0.9 1.4

China 4.8 5.9

Where cotton is grown?Where cotton is grown?

Cotton is a subtropical plant that grows in many warm areas of the world. It Cotton is a subtropical plant that grows in many warm areas of the world. It started out started out as a plant of the tropics but today it is grown in other warm as a plant of the tropics but today it is grown in other warm areas that have at least 200 areas that have at least 200 frost-free frost-free days. The most important cotton-days. The most important cotton-growing countries are the USA, China, India, Pakistan and Australia.growing countries are the USA, China, India, Pakistan and Australia.

China produces about 30% of the world’s cotton fibre, mostly in the China produces about 30% of the world’s cotton fibre, mostly in the eastern part of the country. In the United States cotton is grown in the eastern part of the country. In the United States cotton is grown in the southern states, the biggest cotton producer is Texas. southern states, the biggest cotton producer is Texas.

Cotton needs a hot, sunny climate to grow. The plant needs Cotton needs a hot, sunny climate to grow. The plant needs soil soil that is that is wellwell - - drained drained and a lot of rainfall during the growing season. During the and a lot of rainfall during the growing season. During the harvest harvest season it should be sunny and dry. Some areas grow cotton on season it should be sunny and dry. Some areas grow cotton on irrigated irrigated land. land.

Cotton needs Cotton needs soil soil that has a lot of that has a lot of nitrogen nitrogen in it. Farmers use chemical in it. Farmers use chemical fertilizers fertilizers to to improve improve the the soilsoil . .

Growing and processing cottonGrowing and processing cotton

Cotton plants can reach a Cotton plants can reach a height height of up to 2 meters.of up to 2 meters.

After After plowing plowing the the soil soil in spring cotton in spring cotton seeds seeds are planted are planted in in rows rows by hand or machine. Three weeks after the plants by hand or machine. Three weeks after the plants come out flower come out flower buds buds begin to form. They begin to form. They produce produce white white flowers that turn red and flowers that turn red and fall offfall off . The flowers have a green . The flowers have a green fruit, called boll, which has fruit, called boll, which has seeds seeds in it. White in it. White fiber fiber of of different different lengths lengths grows around the grows around the seedsseeds . Cotton can be . Cotton can be harvested harvested when the boll when the boll bursts bursts open and shows the fibers open and shows the fibers inside. The longest fibers are up to 6 cm long and are used inside. The longest fibers are up to 6 cm long and are used for the best for the best clothcloth . Most fibers, . Most fibers, however however ,are much ,are much smaller smaller

During the During the growth growth period cotton farmers must be careful that period cotton farmers must be careful that their crop does not get any their crop does not get any diseasesdiseases . They . They spray insecticides spray insecticides to keep insects away from the plant. Such insects to keep insects away from the plant. Such insects destroy destroy almost almost 15 % of the world’s cotton every year. 15 % of the world’s cotton every year. Weeds Weeds also do also do damage damage to to the cotton plants. They take away the cotton plants. They take away moisture moisture that plants need so that plants need so much.much.

Cotton is Cotton is harvested harvested about 150 to 200 days after farmers plant it. about 150 to 200 days after farmers plant it. In In industrial countries picking machines industrial countries picking machines drive through the drive through the fields, fields, harvest harvest the cotton and transport it onto a the cotton and transport it onto a trailertrailer . In the . In the Third World cotton harvesting is often done by hand.Third World cotton harvesting is often done by hand.

Gins separate Gins separate the cotton fiber from the the cotton fiber from the seedsseeds . Cotton is then . Cotton is then combedcombed , dried, cleaned and pressed into , dried, cleaned and pressed into balesbales . Cotton buyers . Cotton buyers or or brokers brokers buy the buy the raw raw cotton and then sell it to cotton and then sell it to textile millstextile mills . . There, spinning There, spinning machines spin machines spin cotton into cotton into yarnyarn . The yarn is . The yarn is woven woven into cloth, which is into cloth, which is bleached bleached and sometimes and sometimes dyeddyed . .

CHARATERISTICSCHARATERISTICS OFOF COTTONCOTTON

Cotton, as a natural cellulosic fiber, has a lot of characteristics, Cotton, as a natural cellulosic fiber, has a lot of characteristics, such as:such as:

Comfortable Soft hand Comfortable Soft hand Good absorbency Good absorbency Color retention Color retention Prints well Prints well Machine-washable Machine-washable Dry-cleanable Dry-cleanable Good strength Good strength Drapes well Drapes well Easy to handle and sew.Easy to handle and sew.

END USES OF COTTON:END USES OF COTTON:

Apparel - Wide range of wearing apparel: Apparel - Wide range of wearing apparel: blouses, shirts, dresses, children's wear, blouses, shirts, dresses, children's wear, active wear, separates, swimwear, suits, active wear, separates, swimwear, suits, jackets, skirts, pants, sweaters, hosiery, jackets, skirts, pants, sweaters, hosiery, neckwear. neckwear.

Home Fashion - curtains, draperies, Home Fashion - curtains, draperies, bedspreads, comforters, throws, sheets, bedspreads, comforters, throws, sheets, towels, table cloths, table mats, napkinstowels, table cloths, table mats, napkins

FIBER STRUCTURE AND FIBER STRUCTURE AND FORMATIONFORMATION

The botanical name of American The botanical name of American Upland cotton is Upland cotton is Gossypium HirsutumGossypium Hirsutum and has been developed from and has been developed from cottons of Central America. Upland cottons of Central America. Upland varieties represent approximately varieties represent approximately 97% of U.S. production. 97% of U.S. production.

RAW COTTON RAW COTTON COMPOSITION:COMPOSITION: Cellulose 80-90%

Water 6-8%

Waxes and fats 0.5 - 1%

Proteins 0 - 1.5%

Hemicelluloses and pectin

4 - 6%

Ash 1 - 1.8%

REPEAT UNIT OF CELLULOSE :REPEAT UNIT OF CELLULOSE :

The current consensus regarding cellulose crystalline (X-ray The current consensus regarding cellulose crystalline (X-ray diffraction) is that fibers are essentially 100% crystalline and that diffraction) is that fibers are essentially 100% crystalline and that very small crystalline units imperfectly packed together cause the very small crystalline units imperfectly packed together cause the observed disorder. observed disorder.

The density method used to determine cellulose crystalline is The density method used to determine cellulose crystalline is based on the density gradient column, where two solvents of based on the density gradient column, where two solvents of different densities are partially mixed. Degree of Crystalline is different densities are partially mixed. Degree of Crystalline is then determined from the density of the sample, while densities of then determined from the density of the sample, while densities of crystalline and amorphous cellulose forms are known (1.505 and crystalline and amorphous cellulose forms are known (1.505 and 1.556 respectively). Orientation of untreated cotton fiber is poor 1.556 respectively). Orientation of untreated cotton fiber is poor because the crystallites are contained in the micro fibrils of the because the crystallites are contained in the micro fibrils of the secondary wall, oriented in the steep spiral (25-30o) to the fiber secondary wall, oriented in the steep spiral (25-30o) to the fiber axis. axis.

PHYSICAL PROPERTIES OF COTTONPHYSICAL PROPERTIES OF COTTON     FIBER LENGTH : ItFIBER LENGTH : It is described as the average length of is described as the average length of

the longer one-half of the fibers. This measure is taken by the longer one-half of the fibers. This measure is taken by scanning a "beard " of parallel fibers through a sensing scanning a "beard " of parallel fibers through a sensing region. The beard is formed from the fibers taken from the region. The beard is formed from the fibers taken from the sample, clasped in a holding clamp and combed to align the sample, clasped in a holding clamp and combed to align the fibers. Typical lengths of Upland cottons might range from fibers. Typical lengths of Upland cottons might range from 0.79 to 1.36 inch. 0.79 to 1.36 inch.

LENGTH UNIFORMITY: LENGTH UNIFORMITY: Length uniformity ratio is Length uniformity ratio is determined as a ratio between the mean length and the determined as a ratio between the mean length and the upper half mean length of the fibers and is expressed as a upper half mean length of the fibers and is expressed as a percentage. percentage.

Chemical structure and properties Chemical structure and properties of cotton of cotton

Highly crystalline cellulose has been shown to Highly crystalline cellulose has been shown to decompose at higher temperatures, for instance decompose at higher temperatures, for instance 380 C. Blocking the primary hydroxyl groups of 380 C. Blocking the primary hydroxyl groups of cellulose prevents depolymerization, thus cellulose prevents depolymerization, thus reducing production of volatiles. The reduction of reducing production of volatiles. The reduction of flammable gases is accompanied by more flammable gases is accompanied by more complete intra-ring and inter-ring dehydration, complete intra-ring and inter-ring dehydration, giving rise to keto-enol tautomers and ethermic giving rise to keto-enol tautomers and ethermic linkages, respectively. The carbonyl groups so linkages, respectively. The carbonyl groups so formed can participate in a variety of reactions, formed can participate in a variety of reactions, leading to cross-linking, thus increasing char leading to cross-linking, thus increasing char formation as well as carbon dioxide. formation as well as carbon dioxide.

Fiber developmentFiber development Fiber structures during cell growth:Fiber structures during cell growth: The structure of cotton fibers has been mainly from The structure of cotton fibers has been mainly from

investigation of the matured fibers in their dried state. investigation of the matured fibers in their dried state. Although the biochemical nature of cotton cell structure, Although the biochemical nature of cotton cell structure, particularly during early cell growth, has been extensively particularly during early cell growth, has been extensively studied, the development macrostructure of the main studied, the development macrostructure of the main constituent of the fiber, cellulose, is not as well understood. constituent of the fiber, cellulose, is not as well understood. Cotton fibers are the largest (longest) single cells in nature. Cotton fibers are the largest (longest) single cells in nature. The fibers are single-celled outgrowths from individual The fibers are single-celled outgrowths from individual epidermal cells on the outer integument of the ovules in the epidermal cells on the outer integument of the ovules in the cotton fruit. The primary cell walls continue to elongate cotton fruit. The primary cell walls continue to elongate until reaching the final fiber lengths of 22 to 35 mm inabout until reaching the final fiber lengths of 22 to 35 mm inabout 20 to 25 days. This primary cell wall is very thin (0.2 to 0.4 20 to 25 days. This primary cell wall is very thin (0.2 to 0.4 mm) and extensible. Secondary wall synthesis starts mm) and extensible. Secondary wall synthesis starts around 15 to 22 days past anthesis and continues for 30 to around 15 to 22 days past anthesis and continues for 30 to 40 days. The cellulose formation is about 130 ng/mm.40 days. The cellulose formation is about 130 ng/mm.

Twist and convolution Twist and convolution The formation of twists or convolution occurs when the fully The formation of twists or convolution occurs when the fully

hydrated cylindrical fibers collapse from the loss of fluids hydrated cylindrical fibers collapse from the loss of fluids and drying upon maturation and boll opening or as and drying upon maturation and boll opening or as previously shown during light microscopy observation. on previously shown during light microscopy observation. on developing SJ-2 fibers, typical twists were observed on 28- developing SJ-2 fibers, typical twists were observed on 28- dpa fibers whereas 21 dpa fibers tend to roll and fold onto dpa fibers whereas 21 dpa fibers tend to roll and fold onto themselves. The lateral dimensions of convoluted fibers are themselves. The lateral dimensions of convoluted fibers are characterized by their ribbon or fiber width and twist characterized by their ribbon or fiber width and twist thickness. The fiber widths decrease from drying. The twist thickness. The fiber widths decrease from drying. The twist thicknesses increase with fiber development, from 6.5 mm thicknesses increase with fiber development, from 6.5 mm at 21 dpa to 10.5 mm at 40 dpa and maturity. The twist at 21 dpa to 10.5 mm at 40 dpa and maturity. The twist frequency or the lengths between twists have been found frequency or the lengths between twists have been found to be highly irregular along an individual fiber as well as to be highly irregular along an individual fiber as well as among fibers. among fibers.

Cotton fiber qualityCotton fiber quality Measures of cotton fiber quality may be described Measures of cotton fiber quality may be described

by any of, or in relation to, the chemical and by any of, or in relation to, the chemical and physical properties. The reason for attributing physical properties. The reason for attributing value to cotton is to gain premiums from the value to cotton is to gain premiums from the market on the basis of that cotton’s suitability for market on the basis of that cotton’s suitability for particular end uses. In fact it can be said that particular end uses. In fact it can be said that cotton fibre quality is the utility particular cotton cotton fibre quality is the utility particular cotton achieves in the textile processes involved in its achieves in the textile processes involved in its conversion to the final product. Traditionally, the conversion to the final product. Traditionally, the most desirable cotton (most desirable cotton (Gossypium spp.Gossypium spp.) is said to) is said to

be as white as snow, as strong as steel, as fine as be as white as snow, as strong as steel, as fine as silk and as long as wool.silk and as long as wool.

Short fiber contentShort fiber content:: The most common definition of short fiber content (SFC) is The most common definition of short fiber content (SFC) is

the proportion by weight of fiber shorter than one half inch the proportion by weight of fiber shorter than one half inch (12.7 mm). The value is of concern to textile manufacturers (12.7 mm). The value is of concern to textile manufacturers because it relates directly to the amount of waste extracted because it relates directly to the amount of waste extracted in combing and cotton with high values has a detrimental in combing and cotton with high values has a detrimental effect on the quality of yarn. Short fiber content measured effect on the quality of yarn. Short fiber content measured by the HVI is referred to as short fiber index (SFI) and is the by the HVI is referred to as short fiber index (SFI) and is the most widely used value to describe SFC in a sample, even most widely used value to describe SFC in a sample, even though short fibers are not actually measured directly by though short fibers are not actually measured directly by the HVI Fibro graph, nor can the instrument be calibrated. the HVI Fibro graph, nor can the instrument be calibrated. Typical SFI values vary from 4–12% in ginned lint and are Typical SFI values vary from 4–12% in ginned lint and are much lower in un-ginned lint. Precision is generally poor by much lower in un-ginned lint. Precision is generally poor by comparison with test methods for other properties. comparison with test methods for other properties.

Measurement of fiber maturityMeasurement of fiber maturity:: It is easy to define fiber maturity, measurement is more It is easy to define fiber maturity, measurement is more

difficult. Limitations of the test methods currently available difficult. Limitations of the test methods currently available are slow test times making large numbers of are slow test times making large numbers of measurements impractical and/or the test methods measurements impractical and/or the test methods measure fiber parameters not solely related to fiber measure fiber parameters not solely related to fiber maturity, e.g. Micromere measures specific surface area by maturity, e.g. Micromere measures specific surface area by the air pressure differential across a weighed plug of the air pressure differential across a weighed plug of randomly distributed fibers. Maturity can also be expressed randomly distributed fibers. Maturity can also be expressed as the absolute wall thickness or wall area measured as the absolute wall thickness or wall area measured directly from microscope images of transverse sections. directly from microscope images of transverse sections. However, because average wall thickness tends to increase However, because average wall thickness tends to increase with increasing perimeter, it is an unsuitable measure for with increasing perimeter, it is an unsuitable measure for comparing levels of maturity between different cottons. comparing levels of maturity between different cottons. Moreover, the process of sectioning cotton fibers and Moreover, the process of sectioning cotton fibers and measuring their cross-sectional area is a process fraughtmeasuring their cross-sectional area is a process fraught

with experimental and sampling type. with experimental and sampling type.

Measurement of fiber finenessMeasurement of fiber fineness: : The Micromere is the most widely used test method for The Micromere is the most widely used test method for

obtaining estimates of cotton fiber fineness. The test obtaining estimates of cotton fiber fineness. The test measures the resistance offered by a weighed plug of fibers measures the resistance offered by a weighed plug of fibers to a metered airflow. The test was incorporated into HVI to a metered airflow. The test was incorporated into HVI lines from the beginning of their development and has been lines from the beginning of their development and has been changed to improve test time and precision from the earlier changed to improve test time and precision from the earlier laboratory bench-top instrument of the late 1940s, which laboratory bench-top instrument of the late 1940s, which took a couple of minutes to measure a well blended and took a couple of minutes to measure a well blended and conditioned sample of 50grains (3.24 grams) in weight. The conditioned sample of 50grains (3.24 grams) in weight. The HVI version now takes a 10 gram sample of raw, unblended HVI version now takes a 10 gram sample of raw, unblended but conditioned fiber from the bale sample and completes but conditioned fiber from the bale sample and completes the test in seconds. The scale on the Micronaire is marked the test in seconds. The scale on the Micronaire is marked in micrograms per inch, which is based on an observed in micrograms per inch, which is based on an observed linear relationship between air permeability and linear linear relationship between air permeability and linear density for a range of cotton samples of similar maturity. density for a range of cotton samples of similar maturity.

The Economics of Roller Ginning The Economics of Roller Ginning Technology and Implications for Technology and Implications for

African Cotton SectorAfrican Cotton Sector This study undertaken after the completion of the This study undertaken after the completion of the

comparative analysis of organization and performance of comparative analysis of organization and performance of cotton sectors in Sub-Saharan Africa. It is published bycotton sectors in Sub-Saharan Africa. It is published by

the World Bank in 2008. The objective of this the World Bank in 2008. The objective of this complementary study is to assess the advantages and complementary study is to assess the advantages and disadvantages of the main available technologies to disadvantages of the main available technologies to separate the lint from the raw cotton roller ginning and separate the lint from the raw cotton roller ginning and saw ginning – and carry out an economic analysis of the saw ginning – and carry out an economic analysis of the respective benefits of these two technologies for cotton respective benefits of these two technologies for cotton producing countries of Sub-Saharan Africa. The study producing countries of Sub-Saharan Africa. The study documents the history and current state of cotton ginning documents the history and current state of cotton ginning technology throughout the world, provides a basic technology throughout the world, provides a basic description of the main technologies used, their recent description of the main technologies used, their recent developments and gives an overview of the ginning developments and gives an overview of the ginning process.process.

It examines and compares the performance of roller and It examines and compares the performance of roller and saw technologies in terms of investment and processing saw technologies in terms of investment and processing costs, operational requirements, quality and prices of lint. costs, operational requirements, quality and prices of lint.

It assesses the relevance of roller ginning for Sub-Saharan It assesses the relevance of roller ginning for Sub-Saharan countries, particularly for West and Central African countries, particularly for West and Central African countries, and discusses the incidence that the use of this countries, and discusses the incidence that the use of this technology could have on the future competitiveness of technology could have on the future competitiveness of cotton sectors. The study shows that the choice of ginning cotton sectors. The study shows that the choice of ginning technology is an important factor of performance and is in technology is an important factor of performance and is in turn influenced by the cotton sector structure. The typeturn influenced by the cotton sector structure. The type

of ginning technology also has an impact on lint quality, of ginning technology also has an impact on lint quality, and, as roller ginning is less damaging to the fiber than saw and, as roller ginning is less damaging to the fiber than saw ginning, it can generate a price premium. ginning, it can generate a price premium.

The overall economic advantage of roller gins vs. The overall economic advantage of roller gins vs. saw gins appears to be significant in the Sub- saw gins appears to be significant in the Sub- Saharan African context and likely to increase in Saharan African context and likely to increase in the future as the demand for quality is becomingthe future as the demand for quality is becoming

more and more stringent. Thus, although there more and more stringent. Thus, although there are technical and organizational issues to address are technical and organizational issues to address in order to fully capture the benefits of the in order to fully capture the benefits of the technology, the introduction of roller ginning is technology, the introduction of roller ginning is likely to improve the competitiveness of African likely to improve the competitiveness of African cotton and facilitate the transition towards more cotton and facilitate the transition towards more competitive cotton sectors.competitive cotton sectors.

GENETIC STUDIES OF FIBER GENETIC STUDIES OF FIBER QUALITY CHARACTERS IN QUALITY CHARACTERS IN

UPLAND COTTONUPLAND COTTON Five upland cotton cultivars were crossed in a Five upland cotton cultivars were crossed in a

complete dialed crossing system to investigate complete dialed crossing system to investigate inheritance pattern and combining ability of inheritance pattern and combining ability of parents for different fiber quality traits like staple parents for different fiber quality traits like staple length, fiber strength, fineness and uniformity. length, fiber strength, fineness and uniformity. The study was carried out in the Department of The study was carried out in the Department of Plant Breeding and Genetics, University of Plant Breeding and Genetics, University of Agriculture, Faisalabad during the years 2005-07. Agriculture, Faisalabad during the years 2005-07. Highly significant differences were found among Highly significant differences were found among the genotypes for all the traits under study. the genotypes for all the traits under study. Genetic analysis of the data also revealed highly Genetic analysis of the data also revealed highly significant effects due to general as well as significant effects due to general as well as specific combining ability (P ≤ 0.01) for all the specific combining ability (P ≤ 0.01) for all the fiber quality characters. fiber quality characters.

Upland cotton (Upland cotton (Gossypium hirsutum)Gossypium hirsutum) is the most important is the most important fiber crop in the world, and in Pakistan it is the mainstay of fiber crop in the world, and in Pakistan it is the mainstay of the economy. Cotton is the main source of foreign the economy. Cotton is the main source of foreign exchange earnings and brings about 65 % of the total exchange earnings and brings about 65 % of the total annual earning from the export of raw cotton material and annual earning from the export of raw cotton material and the finished products. The crop not only meets the needs of the finished products. The crop not only meets the needs of fiber requirements of local industry but also provides food fiber requirements of local industry but also provides food in the form of edible oil. Due to immense importance of in the form of edible oil. Due to immense importance of cotton crop in the country’s economy, the cotton breeders cotton crop in the country’s economy, the cotton breeders made great strides for improving cotton plant utilizing made great strides for improving cotton plant utilizing available genetic resources which resulted in numerous available genetic resources which resulted in numerous high yielding cultivars with better fiber quality traits. But high yielding cultivars with better fiber quality traits. But due to the increasing consumption of fiber, there is need to due to the increasing consumption of fiber, there is need to further speed up efforts for continued genetic improvement further speed up efforts for continued genetic improvement in cotton plant for yield and fiber quality traits.in cotton plant for yield and fiber quality traits.

MATERIALS AND METHODS:MATERIALS AND METHODS:

- Genetic material.- Genetic material.

- Green house experiment. - Green house experiment.

- Field experiment.- Field experiment.

- Laboratory testing.- Laboratory testing.

- Statistical analysis.- Statistical analysis.

RESULTS AND DISCUSSIONRESULTS AND DISCUSSION

In the present investigations, data on four fiberIn the present investigations, data on four fiberquality characters i.e. staple length, fiber fineness, fiberquality characters i.e. staple length, fiber fineness, fiberstrength and fiber uniformity were subjected to analysisstrength and fiber uniformity were subjected to analysisof variance. Highly significant differences (P ≤ 0.01)of variance. Highly significant differences (P ≤ 0.01)were found among the genotypes for all the traits. were found among the genotypes for all the traits. Significant mean squares for each of the charactersSignificant mean squares for each of the charactersallowed the use of Griffing’s approach (1956) to studyallowed the use of Griffing’s approach (1956) to studythe magnitude of variance due to the effects of combiningthe magnitude of variance due to the effects of combiningabilities of the parents and inheritance pattern of variousabilities of the parents and inheritance pattern of variousfiber traits. Genetic analysis of the data revealed highlyfiber traits. Genetic analysis of the data revealed highlysignificant effects due to general and specific combiningsignificant effects due to general and specific combiningability (P ≤ 0.01) for all the fiber quality characters.ability (P ≤ 0.01) for all the fiber quality characters.

The reciprocal effects were non-significant for staple length, The reciprocal effects were non-significant for staple length, fiber strength and fiber fineness while fiber uniformity, fiber strength and fiber fineness while fiber uniformity, demonstrated significant reciprocal effects. The magnitude demonstrated significant reciprocal effects. The magnitude of genetic variance due to specific combining ability of genetic variance due to specific combining ability appeared to be greater than that of general combining appeared to be greater than that of general combining ability for staple length, fiber strength, fiber fineness and ability for staple length, fiber strength, fiber fineness and fiber uniformity respectively resulting in the magnitude of fiber uniformity respectively resulting in the magnitude of variance due to dominance was greater than that of variance due to dominance was greater than that of additive effects. These results revealed that staple length, additive effects. These results revealed that staple length, fiber strength, fiber fineness and fiber uniformity were fiber strength, fiber fineness and fiber uniformity were conditioned largely by non-additive gene effects as the conditioned largely by non-additive gene effects as the magnitude of dominance variance was greater than magnitude of dominance variance was greater than additive variance for all the characters suggesting the additive variance for all the characters suggesting the occurrence of heterosis. Thus based on this information, the occurrence of heterosis. Thus based on this information, the present genetic material may be utilized for exploitation of present genetic material may be utilized for exploitation of hybrid vigor through the development of hybrid seed for hybrid vigor through the development of hybrid seed for the characters. the characters.

Cotton Consumption in Cotton Consumption in BangladeshBangladesh

Year Production Land used Consumption Fabric producedYear Production Land used Consumption Fabric produced

ton Hactre ton meterton Hactre ton meter

2012/13 23455 40000 980000 6.4 billion2012/13 23455 40000 980000 6.4 billion 2013/14 26182 45000 1080000 6.6 billion2013/14 26182 45000 1080000 6.6 billion

Cotton is the second important cash crop in Bangladesh after Jute.Cotton is the second important cash crop in Bangladesh after Jute.

Bangladesh Cotton Development Board (CDB) conducts adoptive fields trails of Bangladesh Cotton Development Board (CDB) conducts adoptive fields trails of cotton varieties/hybrids and also responsible for providing extension cotton varieties/hybrids and also responsible for providing extension services to the cotton farmers.services to the cotton farmers.

Short staple upland cotton locally known as Comilla cotton.Short staple upland cotton locally known as Comilla cotton.

Abbreviations and AcronymsAbbreviations and Acronyms

AFIS Advanced Fiber Information System (Uster Technologies AG)AFIS Advanced Fiber Information System (Uster Technologies AG) ARS Agricultural Research Service (USDA)ARS Agricultural Research Service (USDA) BCGA British Cotton Growers AssociationBCGA British Cotton Growers Association BPH Bales per HourBPH Bales per Hour CFC Common Fund for CommoditiesCFC Common Fund for Commodities CFDT Compagnie Française pour le Développement des Fibres TextilesCFDT Compagnie Française pour le Développement des Fibres Textiles CFR (C+F) Cost and FreightCFR (C+F) Cost and Freight CIS Community of Independent StatesCIS Community of Independent States cts/lb Cents per Poundcts/lb Cents per Pound DR Double RollerDR Double Roller ELS Extra Long StapleELS Extra Long Staple ESA East and Southern AfricaESA East and Southern Africa est. Estimatedest. Estimated EXW Ex-worksEXW Ex-works G. GossypiumG. Gossypium G&P Ginning and pressingG&P Ginning and pressing GM Genetically ModifiedGM Genetically Modified GOT Ginning outturn ratioGOT Ginning outturn ratio GPT Gram per TexGPT Gram per Tex HD High densityHD High density hp Horsepowerhp Horsepower HS High SpeedHS High Speed HVI High Volume InstrumentHVI High Volume Instrument

ICAC International Cotton Advisory CommitteeICAC International Cotton Advisory Committee kg Kilogramkg Kilogram ksh kg of lint per saw per hourksh kg of lint per saw per hour kWh KiloWatt per hourkWh KiloWatt per hour lb Poundlb Pound L/C Lint cleanerL/C Lint cleaner LS Long StapleLS Long Staple M MiddlingM Middling mm Millimetermm Millimeter NM New MexicoNM New Mexico t Metric tont Metric ton N/A Non availableN/A Non available Ne English yarn countNe English yarn count RG Roller GinRG Roller Gin Rp RupeeRp Rupee rpm Revolutions per minuterpm Revolutions per minute SCCL Sudan Cotton Company LtdSCCL Sudan Cotton Company Ltd SCF Seed coat fragmentSCF Seed coat fragment SFC Short fiber contentSFC Short fiber content SG Saw GinSG Saw Gin

SITC Standardized Instrument for Testing of CottonSITC Standardized Instrument for Testing of Cotton SJV San Joachin Valley (California)SJV San Joachin Valley (California) SLM Strict Low MiddlingSLM Strict Low Middling SM Strict MiddlingSM Strict Middling sqm Square metersqm Square meter SR Single RollerSR Single Roller SSA Sub-Saharan AfricaSSA Sub-Saharan Africa TCB Tanzanian Cotton BoardTCB Tanzanian Cotton Board UD Universal DensityUD Universal Density UHML Upper High Mean LengthUHML Upper High Mean Length UNIDO United Nations Industrial Development OrganizationUNIDO United Nations Industrial Development Organization USAID United States Agency for International DevelopmentUSAID United States Agency for International Development USDA United States Department of AgricultureUSDA United States Department of Agriculture US$ U.S. dollarUS$ U.S. dollar WACIP West African Cotton Improvement Program (USAID)WACIP West African Cotton Improvement Program (USAID) WCA West and Central AfricaWCA West and Central Africa

Thanks to all.Thanks to all. A.k.m. Tahjibur RahmanA.k.m. Tahjibur Rahman Lecturer buft;shantamarium Lecturer buft;shantamarium

universityuniversity Cell :01711046722Cell :01711046722 E mail:t_rahman71@yahoo.comE mail:t_rahman71@yahoo.com