Factors Affecting Fiber Quality

There are many Factors that effect agro-fiber properties. For example,

* What part of the plant the fiber came from

* The age of the plant when the fiber was harvested

* How the fiber was isolated

* Permeability and hydroscopicity of the plant cell wall.


Fiber Length

The variability in fiber length can be explained primarily by genetics. Fiber elongation begins at bloom and continues for about 21 days.Starting with a variety that has better genetic potential for fiber length will minimize the probability of producing fiber length in the discount range.Moisture stress during this period will reduce fiber length in all varieties. Severe weathering after bolls have opened can reduce fiber length because more breakage can be expected in the ginning process.

Fiber Strength

Fiber strength is translated directly to yarn strength. In addition to producing stronger yarns, stronger fibers allow for faster and more efficient processing. Final strength level is achieved early in the fiber development stage; however, weathering can weaken the primary wall and cause strength levels to decline slightly in the weeks after boll opening.

Fiber strength is the most variety-dependent property. Any factor that causes either physical or microbial damage to the fiber can reduce strength. Severe drying at the gin also can reduce strength. The best management practice for fiber strength is variety selection, followed by sufficient potassium levels at the root zone in the soil.

Micronaire

Micronaire is determined both by fiber diameter and the amount of secondary wall development prior to boll opening. Micronaire is an indirect measure of both fiber maturity and fiber fineness (perimeter).

"There must be at least 100 fibers in the cross-section of yarn, so high micronaire fibers can become a limiting factor in spinning fine yarn.Fine fibers that are immature can break during processing and they do not dye well. This is why there are price discounts for both high and low micronaire. Fiber biological fineness is influenced by genetics, but environment and management can substantially affect fiber maturity.

Length Uniformity and Short Fiber Content

Length uniformity is now part of the premium/discount valuation of cotton. Short fibers within a process mix of cotton cannot wrap around each other and contribute little or nothing to yarn strength. Short fibers indirectly cause product defaults and directly contribute to higher waste and lower manufacturing efficiency.

Since short fiber content and length uniformity are derived from length, they are influenced by the same factors as length. Crop management practices that influence where bolls are located on the plant can impact short fiber content levels. Uniform fruit retention patterns encourage better length uniformity.

Color Grade

Both yellowness and brightness (reflectance) define color grade. Less total cellulose production during development can lead to lower brightness levels. The direct impact of color is in the bleaching process. Textile mills must control the color of their cotton within narrow limits to achieve a consistent fabric shade. Cotton loses some luster and brightness the longer it is subject to weathering.

Environmental factors account for 79 percent of the color variability in cottonr. When total rainfall after the cotton opens exceeds 2 inches, loss in color grade will occur. Discoloration can also be caused by the action of microorganisms in connection with boll rot or insect damage. Cotton stored in modules with moisture content above 11 percent, excessive trash, or improper covering can lead to reduction in color.

Leaf Grade

The amount of leaf grade is not a function of physical fiber development. While burs, stems or weed plant material can contribute to leaf grade, the major source of trash is leaf and bract material. Leaf grade has the most direct effect on manufacturing waste in the textile mill. Excessive leaf trash requires more cleaning and air-handling equipment, and impacts product quality.

Variety can impact leaf grade when there are differences in the amount of trichomes (hairiness) in the leaf and bract. Small bits of hairy leaves cling to fibers making their removal more difficult. High plant population, delayed maturity, excessive vegetative growth, lack of weed control and defoliation problems impact harvest efficiency and increase the amount of leaf in a bale. 

Nylon Fiber Properties

Density (g/cc) : 1.14

Moisture Regain(%) : 2.8 to 5.0

Elongationat Break(%) : 17 to 45

BreakingTenacity(g/Denier) : 4.0 to 7.2

InitialModulus(CN/tex) : 400

ThermalShrinkage(@ 177 C) : N/A

L.O.I. : ----

MeltingPoint (C/F) : 216/419

Fluorocarbon -Teflon® (PTFE) Properties

Heat : Very heat resistant -350F to 550F. Melts at 620F.

Bleaches &Solvents : Essentially inert to bleaches & solvents

Acids & Alkalis : Excellent but effected by acids & alkali at high temperatures.

Abrasion : Good

Mildew, Aging &Sunlight : Excellent

Aramid(Kelvar®, Nomex®, Tarwon®, Technora®) Properties

Heat : Difficult to ignite. Does not burn or melt. Decomposes at 800F to 932F.

Bleaches &Solvents : Poor in bleach.Excellent solvent resistance.

Acids & Alkalis : Good in dilute acids & bases. Poor in strong acids & bases.

Abrasion : Fair to Good

Mildew, Aging &Sunlight : Excellent resistance to mildew & aging. Degrades when exposed to sunlight.

Fiber Glass Properties

Heat : Does not burn or melt

Bleaches &Solvents : Excellent solvent & bleach resistance.

Acids & Alkalis : Fair

Abrasion : Good

Mildew, Aging &Sunlight : Excellent

Spandez® / Lycra® Fiber Properties

Heat : Sticks at 350-390F. Melts above 500F.

Bleaches &Solvents : Good resistance to oxidizing agents. Poor resistance to bleaches.

Acids & Alkalis : Good

Abrasion : Good in diluted (weak), but degrades in strong acids & bases.

Mildew, Aging &Sunlight : Excellent aging and mildew resistance. Good resistance to sunlight.

Polyethylene Fiber Properties

Heat : Melts at 525F

Bleaches &Solvents : Excellent

Acids & Alkalis : Excellent

Abrasion : Good to Poor

Mildew, Aging &Sunlight : Excellent resistance to mildew.

Nylon Fibre Properties

Heat : Melts at 419F to430F.

Bleaches &Solvents : Will bleach.Degrades in mineral acids & oxidizing agents.

Acids & Alkalis : Insoluble in organic solvents Resists weak acids, inert to alkalis. Hydrolyzed by strong acids

Abrasion : Excellent

Mildew, Aging &Sunlight : Excellent resistance to mildew and aging. Prolonged sun exposure can cause degradation.

Polyester Fiber Properties

Heat :Melts at 500F.

Bleaches &Solvents : Excellent

Acids & Alkalis : Good resistance to weak alkalis & weak acids. Moderate resistance to strong acids & alkali.

Abrasion : Excellent

Mildew, Aging &Sunlight : Excellent resistance to mildew, good aging. Degrades after prolonged exposure to sunlight.

Fiber Testing

Fiber Elongation

There are Three Types of Elongation

Permanent Elongation 

The length which extended during loading did not recover during relaxation

Elastic Elongation

The extensions through which the fibres does return

Breaking Elongation

The maximum extension at which the yarn breaks i.e.permanent and elastic elongation together Elongation is specified as a percentage of the starting length. The elastic elongation is of deceisive importance, since textile products without elasticity would hardly be usable. They must be able to deforme, In order to withstand high loading, but they must also return to shatpe. The greater resistance to crease for wool compared to cotton arises, from the difference in their elongation. For cotton it is 6 -10% and for wool it is aroun 25 - 45%. For normal textile goods, higher elongation are neither necessary nor desirable. They make processing in the spinning mill more difficult, especially in drawing operations.

Fiber Rigidity

The Torsional rigidity of a fibre may be defined as the torque or twisting force required to twist 1 cm length of the fibre through 360 degrees and is proportional to the product of the modulus of rigidity and square of the area of cross-section, the constant of proportionality being dependent upon the shape of the cross-section of the fibre. The torsional rigidity of cotton has therefore been found to be very much dependent upon the gravimetric fineness of the fibres. As the rigidity of fibres is sensitive to the relative humidity of the surrounding atmosphere, it is essential that the tests are carried out in a conditional room where the relative humidity is kept constant.

The Slenderness Ratio

Fibre Stiffness plays a significant role mainly when rolling, revolving, twisting movements are involved. A fibre which is too stiff has difficulty adapting to the movements. It is difficult to get bound into the yarn, which results in higher hairiness. Fibres which are not stiff enough have too little springiness. They do not return to shape after deformation. They have no longitudinal resistance. In most cases this leads to formation of neps. Fibre stiffness is dependent upon fibre substance and also upon the relationship between fibre length and fibre fineness. Fibres having the same structure will be stiffer, the shorter they are. The slendernesss ratio can serve as a measure of stiffness
Slender Ratio = Fibre Length /Fibre Diameter
Since the fibres must wind as they are bound-in during yarn formation in the ring spinning machine, the slenderness ratio also determines to some extent where the fibres will finish up.fine and/or long fibres in the middle coarse and/or short fibres at the yarn periphery.

Trash Content

In additon to usuable fibres, cotton stock contains foreign matter of various kinds. This foreign material can lead to extreme disturbances during processing. Trash affects yarn and fabric quality. Cottons with two different trash contents should not be mixed together, as it will lead to processing difficulties. Optimising process paramters will be of great difficulty under this situation, therefore it is a must to know the amount of trash and the type of trash before deciding the mixing

Shirley Trash Analyser

A popular trash measuring device is the Shirley Analyser, which separates trash and foreign matter from lint by mechanical methods. The result is an expression of trash as a percentage of the combined weight of trash and lint of a sample. This instrument is used

To give the exact value of waste figures and also the proportion of clean cotton and trash in the material

• To select the proper processing sequence based upon the trash content to assess the cleaning efficiency of each machine

• To determine the loss of good fibre in the sequence of opening and cleaning.

Stricter sliver quality requirements led to the gradual evolution of opening and cleaning machinery leading to a situation where blow room and carding machinery were designed to remove exclusively certain specific types of trash particles. This necessitated the segregation of the trash in the cotton sample to different grades determined by their size. This was achieved in the instruments like the Trash Separator and the Micro Dust Trash Analyser which could be considered as modified versions of the Shirley Analyser.

 

The high volume instruments introduced the concept of optical methods of trash measurement which utilised video scanning trash-meters to identify areas darker than normal on a cotton sample surface. Here, the trash content was expressed as the percentage area covered by the trash particles. However in such methods, comparability with the conventional method could not be established in view of the non-uniform distribution of trash in a given cotton sample and the relatively smaller sample size to determine such a parameter. Consequently, it is yet to establish any significant name in the industry.

Quality Testing Instruments

• Fibrogaph-Length

• Pressley Apparatres-Fiber Bundle Strength

• HV I Instrument- Length, Strength, Uniformity, Elongation, Micronaire, Color and Trash

• Stelometer Instrument- Strength, Elongation

• Micronaire -Combined test of fineness & maturity

• Shirley Trash Analyser- Trash Content

• Manual Test- Class & staple length

• Colorimeter- Grey value & yellow ness,Brightness

• Polarised light Microscope or Casricaire test -Maturity

• Photographic film -Neppiness

• Moisture Meter-Moisture

Microfiber

Microfiber is fiber with strands less than one denier. Microfiber is a blend of polyester and polyamide. Fabrics made with microfibers are exceptionally soft and hold their shape well. When high quality microfiber is combined with the right knitting process, it creates an extremely effective cleaning material. This material can hold up to seven times its weight in water. They are also used for some cleaning applications, because of their exceptional ability to absorb oils.

Material of Microfiber

Microfiber is constructed in a blend of 80/20 ratio of polyester/polyamideams. They are made from a warp knitted thread, composed of wedge-shaped polyester filaments with a core of nylon. The fiber's wedge shaped filaments follow surfaces, lift up dirt, and then trap the particles inside the fibers. The capillary effect between the filaments and nylon core creates a high absorbency, which in turn enables this cloth to clean and polish at the same time.
To clean a microfiber cloth, wash with warm soapy water and rinse well. The warm water opens up the fibers, allowing them to release the locked in dirt. Placing the cloths in a washing machine and then drying them in a dryer on low heat is also effective. No fabric softeners of any kind should be used as the chemicals clog up the microfibers, making them less effective. Bleach should also be avoided as it corrodes the fibers over time, making them less effective. Ironing is also potentially damaging.

Functional Uses of Microfiber

Microfiber performance apparel has become a very popular alternative to cotton apparel for athletic wear, such as cycling jerseys, because the microfiber material wicks moisture away from the body, keeping the athlete cool and dry.

Microfiber materials, such as PrimaLoft are also used for thermal insulation as a replacement for down feather insulation in sleeping bags and outdoor equipment, due to its better retention of heat when damp or wet.

Fiber Blending

The process of blending of different fibers into a single fabric is made to improve quality of this fabric and give it the desired properties. But long fibers cannot be used in that process, so they are being cut into smaller staple fibers and only after that they are blended into fabric. Some natural materials in their turn can be blended right away and do not need to be cut into smaller pieces.

Different sorts of natural fibers were used by people of all nations around the world for ages and various fabric weaving techniques allowed them to have different sorts of textile for making clothes. Later, with the development of chemical technologies the number of available materials has ballooned. In fact, new interesting materials are being developed now, so their number is constantly increasing

The production of manmade fibers is more cost effective than that of natural fibers, which is why synthetic fibers are in such great demand in the textile industry. There are two basic types of synthetic material. The first one contains cellulose (it forms cell walls in each plant; cellulose is mainly obtained from wood) like acetate silk, for example, while the other one does not contain any cellulose and is made entirely of chemical substances. And both types of fibers are made in more or less similar way. First of all, the components that are used to form fiber are turned into liquid form by means of solvents. Then this liquid is being squeezed through the very narrow device which is called a spinner. And at the same time thread, that is formed, is treated with special substances to be moulded into solid state. It is a rather uncomplicated process that allows reducing the price of fibers significantly. But still there are certain qualities of natural fibers that synthetic material is deprived of. The simple solution here is blending. Different synthetic materials can be combined with natural material and, thus, fabric will have qualities of both natural and synthetic fibers.

Purposes of Blending

There can be many different purposes of blending, but in most cases blending of different fibers is oriented on getting higher quality of fabrics. Mixing different sorts of fibers leads to better fabric characteristics that can be obtained. But not all sorts of fibers can be blended together, because different qualities of various materials are possible to reach only in certain combinations.

There are many different fibers that are used these days in making clothes and other products that involve cloth. The history of natural materials is pretty long. Fabric weaving has been known for more than 3000 years. The history of manmade fibers is not so impressive. These materials were invented not so long ago, but the quality of synthetic material is just great.

These wonderful qualities give manmade materials a huge range of different uses. They make our everyday life easier and in many professions synthetic materials can even save lives. These materials are also much cheaper in production than usual natural fibers that take a lot of time and efforts to be made. But not all qualities of manmade materials are that great and sometimes it is necessary to have better fabric characteristics.

Lyocell Rayon

A new form of cellulosic fiber, Lyocell is starting to find uses in the nonwovens industry. Lyocell is manufactured using a solvent spinning process, and is produced by only two companies -- Acordis and Lenzing AG. To produce Lyocell, wood cellulose is dissolved directly in n-methyl morpholine n-oxide at high temperature and pressure. The cellulose precipitates in fiber form as the solvent is diluted, and can then be purified and dried. The solvent is recovered and reused. Lyocell has all the advantages of rayon, and in many respects is superior. It has high strength in both dry and wet states, high absorbency, and can fibrillate under certain conditions. In addition, the closed-loop manufacturing process is far more environmentally friendly than that used to manufacture rayon, although it is also more costly.

Tencel Rayon

Unlike viscose rayon, Tencel is produced by a straight solvation process. Wood pulp is dissolved in an amine oxide, which does not lead to undue degradation of the cellulose chains. The clear viscous solution is filtered and extruded into an aqueous bath, which precipitates the cellulose as fibers. This process does not involve any direct chemical reaction and the diluted amine oxide is purified and reused. This makes for a completely contained process fully compatible with all environmental regulations.

Specialty Rayons

Flame Retardant Fibers

Flame retardance is achieved by the adhesion of the correct flame- retardant chemical to viscose. Examples of additives are alkyl, aryl and halogenated alkyl or aryl phosphates, phosphazenes, phosphonates and polyphosphonates. Flame retardant rayons have the additives distributed uniformly through the interior of the fiber and this property is advantageous over flame retardant cotton fibers where the flame retardant concentrates at the surface of the fiber.

Super-Absorbent Rayons

This is being produced in order to obtain higher water retention capacity (although regular rayon retains as much as 100 % of its weight). These fibers are used in surgical nonwovens. These fibers are obtained by including water- holding polymers (such as sodium polyacrylate or sodium carboxy methyl cellulose) in the viscose prior to spinning, to get a water retention capacity in the range of 150 to 200 % of its weight.

Micro-Denier Fibers

Rayon fibers with deniers below 1.0 are now being developed and introduced into the market. These can be used to substantially improve fabric strength and absorbent properties.

Cross-Section Modification of Viscose Rayon

Modification in cross-sectional shape of viscose rayon can be used to dramatically change the fibers' aesthetic and technical properties. One such product is Viloft, a flat cross sectional fiber sold in Europe, which gives a unique soft handle, pleasing drape and handle. Another modified cross section fiber called Fibre ML(multi limbed) has a very well defined trilobal shape. Fabrics made of these fibers have considerably enhanced absorbency, bulk, cover and wet rigidity all of which are suitable for usage as nonwovens .

Polynosic Rayon

Polynosic fibers have a very high degree of orientation, achieved as a result of very high stretching (up to 300 %) during processing. They have a unique fibrillar structure, high dry and wet strength, low elongation (8 to 11 %), relatively low water retention and very high wet modulus.

High Wet Modulus Rayon

These fibers have exceptionally high wet modulus of about 1 g/den and are used as parachute cords and other industrial uses. Fortisan fibers made by Celanese (saponified acetate) has also been used for the same purpose

Cuprammonium Rayon

Cuprammonium Rayon is produced by a solution of cellulosic material in cuprammonium hydroxide solution at low temperature in a nitrogen atmosphere, followed by extruding through a spinnerette into a sulphuric acid solution necessary to decompose cuprammonium complex to cellulose. This is a more expensive process than that of viscose rayon. Its fiber cross- section is almost round.

Acetate Rayon

Cellulose acetate or acetate rayon fiber (1924) is one of the earliest synthetic fibers and is based on cotton or tree pulp cellulose ("biopolymers"). These "cellulosic fibers" have passed their peak as cheap petro-based fibers (nylon and polyester) and have displaced regenerated pulp fibers.

Acetate Fiber Characteristics

• Cellulosic and thermoplastic

• Selective absorption and removal of low levels of certain organic chemicals

• Easily bonded with plasticizers, heat, and pressure

• Acetate is soluble in many common solvents (especially acetone and other organic solvents) and can be modified to be soluble in alternative solvents, including water

• Hydrophilic: acetate wets easily, with good liquid transport and excellent absorption; in textile applications, it provides comfort and absorbency, but also loses strength when wet

• Acetate fibers are hypoallergenic 

Major Industrial Acetate Fiber Uses

Apparel

Blouses, Dresses, Linings, Wedding and party attire, Home furnishings, Draperies, Upholstery and slip covers

High Absorbency Products

Diapers, Feminine Hygiene Products, Cigarette Filters, Surgical Products, and other filters 

Production of Acetate Rayon

The Federal Trade Commission definition for acetate fiber is "A manufactured fiber in which the fiber-forming substance is cellulose acetate. Where not less than 92 percent of the hydroxyl groups are acetylated, the term triacetate may be used as a generic description of the fiber."

Acetate is derived from cellulose by deconstructing wood pulp into a purified fluffy white cellulose. The cellulose is then reacted with acetic acid and acetic anhydride in the presence of sulfuric acid. It is then put through a controlled, partial hydrolysis to remove the sulfate and a sufficient number of acetate groups to give the product the desired properties. The anhydroglucose unit is the fundamental repeating structure of cellulose and has three hydroxyl groups which can react to form acetate esters. The most common form of cellulose acetate fiber has an acetate group on approximately two of every three hydroxyls. This cellulose diacetate is known as secondary acetate, or simply as "acetate".

After it is formed, cellulose acetate is dissolved in acetone into a viscose resin for extrusion through spinnerets (which resemble a shower head). As the filaments emerge, the solvent is evaporated in warm air via dry spinning, producing fine cellulose acetate fibers.

Overview of Rayons

Rayon is a manufactured regenerated cellulose fiber. Because it is produced from naturally occurring polymers, it is neither a truly synthetic fiber nor a natural fiber, it is a semi-synthetic fiber.

Rayon is known by the names viscose rayon and art silk in the textile industry. It usually has a high lustre quality giving it a bright shine. Rayon contains the chemical elements carbon, hydrogen, and oxygen

Carbon Fiber

Manufacturing Process of Carbon Fiber

The conversion of PAN to carbon fibers is normally made in 4 continuous stages

• Oxidation

• Carbonisation(Graphitisation)

• Surface treatment

• Sizing

Uses of Carbon Fiber

Carbon fibers are used primarily in composites, these are structures containing two or more components, in the case of fiber reinforced composites this is the fiber and a resin. A composite containing two types of fiber, eg. carbon and glass, is known as a hybrid composite structure.

The origins of textile reinforced composites are linked to the development of glass fibers, which commenced in 1938 by the Owens Corning Fiberglass Corporation (USA). Original large scale applications included air filtration, thermal and electrical insulation and the reinforcement of plastics. As the technology of textile reinforced composites expanded, a growing demand from the aerospace industry for composite materials with superior properties emeged. In particular, materials with higher specific strength, higher specific moduli and low density were required. Other desirable properties are good fatigue resistance, and dimensional stability. Carbon fibers were developed to meet this demand.

Perlon Fiber

Perlon was used as fabric for high pressure hose in airplane tires, as stiff bristles for cleaning weapons, for cords and ropes for parachutes - but also for lady´s stockings as a Christmas present for the wives of I.G.-Farben managers in 1943 and as reinforcement in socks used by the German armed forces. For the time being, the civil use of Perlon was unthinkable. Spinneret for the production of Perlon filaments. (Perlon is produced in the melt spinning process. The material is melted at high temperatures and continuously pressed through spinnerets by gear pumps. When cooled at room temperature, the mass congeals into fine filaments that can be pulled off and wound at a fast rate).

Teflon Fiber

Teflon is the brand name of a polymer compound discovered by Roy J. Plunkett (1910-1994) of DuPont in 1938 and introduced as a commercial product in 1946. It is a thermoplastic fluoropolymer. Teflon is polytetrafluoroethylene (PTFE), a polymer of fluorinated ethylene.

Teflon is also used as the trade name for a polymer with similar properties, perfluoroalkoxy polymer resin (PFA)

PTFE has the lowest coefficient of friction of any known solid material. It is used as a non-stick coating for pans and other cookware. PTFE is very non-reactive, and so is often used in containers and pipework for reactive chemicals. Its melting point varies between 260 °C (FEP) and 327 °C (PTFE), depending on which specific Teflon polymer is being discussed.

PTFE is sometimes said to be a spin-off from the US space program with more down-to-earth applications; this is an urban legend, as teflon cooking pans were commonplace before Yuri Gagarin's flight in 1961. PTFE was discovered serendipitously by Roy Plunkett of DuPont in 1938, while attempting to make a new CFC refrigerant, when the perfluorethylene polymerized in its storage container. DuPont patented it in 1941, and registered the Teflon trademark in 1944.

An early advanced use was in the Manhattan Project, as a material to coat valves and seals in the pipes holding highly-reactive uranium hexafluoride in the vast Uranium enrichment plant at Oak Ridge, Tennessee, when it was known as K416.

It was first sold commercially in 1946 and by 1950, DuPont was producing over a million pounds (450 t) per year in Virginia.

Teflon has been supplemented with another DuPont product, Silverstone, a three-coat fluoropolymer system that produces a more durable finish than Teflon. Silverstone was released in 1976.

Amongst many other industrial applications, PTFE is used to coat certain types of hardened, armour-piercing bullets, so as to reduce the amount of wear on the firearm's rifling. These are often mistakenly referred to as "cop-killer" bullets on account of PTFE's supposed ability to ease a bullet's passage through body armour. Any armour-piercing effect is, however, purely a function of the bullet's velocity and rigidity rather than a property of PTFE.

PTFE is an excellent electrical insulator with good dielectric properties. This is especially true at high radio frequencies, making it eminently suitable for use as an insulator in cables and connector assemblies and as a material for printed circuit boards. Combined with its high melting temperature this makes it the material of choice as a high performance substitute for the weaker and more meltable polyethylene that is commonly used in low-cost applications.

Lyocell Fiber Characteristics

Lyocell is a fibre made from wood pulp cellulose. It was first manufactured in 1992 by Acordis Cellulosic Fibers, Inc. The only current manufacturer in the United States is Tencel Ltd, who market it under the trademarked brand name Tencel.

The product is also manufactured by the Lenzing-based fiber manufacturer Lenzing AG, under the trademark Lenzing Lyocell. The Federal Trade Commission defines lyocell as "a cellulose fabric that is obtained by an organic solvent spinning process". It classifies the fibre as a sub-category of rayon. The fibre is used in the production of many clothes, such as jeans, trousers and coats

Aramid Fiber

Aramid fibers are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic rated body armor fabric, and as an asbestos substitute. The name is a shortened form of "aromatic polyamide". They are fibers in which the chain molecules are highly oriented along the fiber axis, so the strength of the chemical bond can be exploited.

History of Aramid Fiber
Aromatic polyamides were first introduced in commercial applications in the early 1960s, with a meta-aramid fiber produced by DuPont under the tradename Nomex. This fiber, which handles similarly to normal textile apparel fibers, is characterized by its excellent resistance to heat, as it neither melts nor ignites in normal levels of oxygen. It is used extensively in the production of protective apparel, air filtration, thermal and electrical insulation as well as a substitute for asbestos. Meta-aramid is also produced in the Netherlands and Japan by Teijin under the tradename Teijinconex, in China by Yantai under the tradename New Star and a variant of meta-aramid in France by Kermel under the tradename Kermel.

Production of Aramid Fiber World capacity of para-aramid production is estimated at about 41,000 tons/yr in 2002 and increases each year by 5-10%. In 2007 this means a total production capacity of around 55,000 tons/yr.

Aramid Fiber Characteristics

Aramids share a high degree of orientation with other fibers such as Ultra high molecular weight polyethylene, a characteristic which dominates their properties.

General Properties of Aramid

• Good resistance to abrasion

• Good resistance to organic solvents

• Nonconductive

• No melting point, degradation starts from 500°C

• Low flammability

• Good fabric integrity at elevated

• Sensitive to acids and salts

• Sensitive to ultraviolet radiation

• Prone to static build-up unless finished

Major Industrial Uses

• Flame-resistant clothing

• Heat protective clothing and helmets

• Body armor[competing with PE based fiber products such as Dyneema and Spectra

• Composite materials

• Asbestos replacement (e.g. braking pads)

• Hot air filtration fabrics

• Tires, newly as Sulfron (sulfur modified Twaron)

• Mechanical rubber goods reinforcement

Vinyon Fiber

Vinyon is a synthetic fiber made from polyvinyl chloride. In some countries other than the United States, vinyon fibers are referred to as polyvinyl chloride fibers. It can bind non-woven fibers and fabrics. It was invented in 1939.

It has the same health problems associated with chlorinated polymers. In the past, Vinyon was used a substitute for plant-based filters in tea bags

Vinyon Fiber Characteristics

It doesn't flame, but softens at low temperatures(55 C)high resistance to chemicals. Moisture absorption is less than 0.5% and moisture regained is less than 0.1% 

 

Major Vinyon Fiber Uses

Industrial applications as a bonding agent for non-woven fabrics and products

Production of Vinyon Fiber

The U.S. Federal Trade Commission definition for vinyon fiber is "A manufactured fiber in which the fiber-forming substance is any long chain synthetic polymer composed of at least 85 percent by weight of vinyl chloride units (-CH2-CHCl-)."

Spandex Fiber

Spandex or elastane is a synthetic fiber known for its exceptional elasticity (stretchability). It is stronger and more durable than rubber, its major plant competitor. It was invented in 1959, and when first introduced it revolutionized many areas of the clothing industry.

Spandex is the preferred name in North America, while elastane is most often used elsewhere. A well-known trademark for spandex or elastane is Invista's brand name Lycra; another trademark (also Invista's) is Elaspan.

Spandex Fiber Characteristics

• It can be stretched over 500% without breaking able to be stretched repetitively and still recover original length lightweight abrasion resistant

• Poor strength, but stronger and more durable than rubber.

• Soft, smooth, and supple resistant to body oils, perspiration, lotions, and detergents.

• No static or pilling problems 

Major Spandex Fiber Uses

Apparel and Clothing articles where stretch is desired, generally for comfort and fit, such as:

Athletic, aerobic, and exercise apparel swimsuits/bathing suits, brassiere straps and bra side panels, ski pants, slacks, hosiery, socks, belts 

 

Compression Garments :

Surgical hose, support hose, bicycle pants, foundation garments

Shaped Garments :

Bra cups

Polyester Fiber

Polyester is a category of polymer whose monomer contains the ester functional group. Polyesters fibers are often used to make fabric. Liquid crystalline polyesters are among the first industrially used liquid crystalline polymers. In general they have extremely good mechanical properties and are extremely heat resistant. For that reason, they can be used as an abradable seal in jet engines.

Olefin Fiber

Olefin fiber is a synthetic fiber made from alkenes. It is used in the manufacture of various textiles. Olefin is also referred to as polypropylene, polyethylene or polyolefin. The name comes from the term olefiant gas, an early name for ethylene meaning "oil-forming".

Major Fiber Properties

A manufactured fiber in which the fiber forming substance is any long-chain synthetic polymer composed of at least 85% by weight of ethylene, propylene, or other olefin units.Olefins are produced as a monofilament, multifilament, staple fiber, tow and slit or fibrillated film years with variable tenacities.The fibers are "waxy" colorless, often round in cross section.The fibers are also resistant to moisture and chemicals. Polypropylene is used more for textiles because of its high melting point. The fibers do not take dye very well so colored olefin fibers are produced by adding dye directly to the polymer prior to or during "melt spinning".

Some interior designers prefer olefin to most other fibers because of its attractive appearance and other positive performance aspects along with the low cost aspect as compared to similar products made with different fibers. Along with being moisture and chemical resistant, it is also abrasion resistant, low static, stain resistant, colorfast, strong, very comfortable and extremely lightweight .olefin is the lightest textile fiber. Fiber properties can be modified in a wide range with additives (e.g. UV-, thermal resistance, antibacterial, flame retardant).

Manufacturers of Olefin Fiber

The first commercial producer of an olefin fiber in the United States was Hercules, Inc. (FiberVisions). In 1996, polyolefin was the world's first and only Nobel Prize winning fiber.Other U.S. olefin fiber producers include: Asota, American Fibers and Yarns Co, American Synthetic Fiber LLC, Color-Fi, FiberVisions, Foss Manufacturing Co. LLC, Drake Extrusion, Filament Fiber Technology Inc., TenCate Geosynthetics, Universal Fiber Systems LLC.

Uses of Olefin Fiber

Apparel

Sports & active wear, socks, thermal underwear, lining fabrics. Used in blends for pantyhose, saris, and swimwear.

Home Furnishing

Indoor and outdoor carpets and carpet tiles, carpet backing, Upholstery, draperies, wall coverings, slipcovers, floor coverings

Automotive

Interior fabrics, sun visors, arm rests, door and side panels, trunks, parcel shelfs, resin replacement as binder fibers.

Industrial

Carpets, ropes, geo-textiles that are in contact with the soil, filter fabrics, bagging, concrete reinforcement, heat-sealable paper (e.g. tea- and coffee-bags)

Nylon Fiber

Nylon is a synthetic polymer, a plastic, invented on February 28, 1935 by Wallace Carothers at the E.I. du Pont de Nemours and Company of Wilmington, Delaware, USA. The material was announced in 1938 and the first nylon products; a nylon bristle toothbrush made with nylon yarn (went on sale on February 24, 1938) and more famously, women's stockings (went on sale on May 15, 1940). Nylon fibres are now used to make many synthetic fabrics, and solid nylon is used as an engineering material.

Chemically, nylon is a condensation polymer made of repeating units with amide linkages between them: hence it is frequently referred to as a polyamide. It was the first synthetic fibre to be made entirely from inorganic ingredients: coal, water and air. These are formed into two intermediate chemicals, most commonly hexamethylene diamine and adipic acid (a dicarboxylic acid), which are then mixed to polymerise. The most common variant is nylon 6,6, also called nylon 66, which refers to the fact that both the diamine and the diacid have 6 carbon backbones. The diacid and diamine units alternate in the polymer chain. Therefore, unlike natural polyamides like proteins, the direction of the amide bond reverses at each bond.

Nomex Fiber

NOMEX® is the brand name of a flame retardant meta-aramid material marketed and first discovered by DuPont in the 1970s. It is sold in both fiber and sheet forms and is used as a fabric wherever resistance from heat and flame is required. Both the firefighting and vehicle racing industries use Nomex to create clothing and equipment that can stand up to intense heat. It is the meta variant of the para-aramid Kevlar.


A Nomex hood is a common piece of firefighting equipment. It is placed on the head on top of a firefighter's face mask. The hood protects the portions of the head not covered by the helmet and face mask from the intense heat of the fire. Race car drivers commonly use a similar hood to protect them in the event that a fire engulfs their car. Military pilots wear one-piece coveralls (flight suits) made of over 92% Nomex, to protect them from the possibility of cockpit fires and other mishaps.

Lycra Fiber

Lycra is INVISTA's trademark for a synthetic fabric material with elastic properties of the sort known generically as "spandex". Lycra is commonly used in athletic or active clothing. Lycra as a clothing material is fetishized by some people, perhaps on the basis that the garment forms a "second skin" that acts as a fetishistic surrogate for the wearer's own skin. This is known as lycra fetishism. Lycra is normally one of the fabrics in leggings.

Kevlar Fiber

Kevlar, also known as Twaron and poly-paraphenylene terephthalamide, is a synthetic fibre that is five times stronger than steel, weight for weight. Kevlar is very heat resistant and decomposes above 400 °C without melting. It is usually used in bulletproof vests, in extreme sports equipment, and for composite aircraft construction. It is also used as a replacement for steel cords in car tires, in fire suits and as an asbestos replacement. Kevlar was invented by the DuPont corporation in the early 1960s, following the work of Stephanie Kwolek. Kevlar is a registered trademark of E.I. du Pont de Nemours and Company.

Properties of Kevlar

Kevlar is a type of aramid that consists of long polymeric chains with a parallel orientation. Kevlar derives its strength from intra-molecular hydrogen bonds and phenyl stacking interactions between aromatic groups in neighboring strands. These interactions are much stronger than the van der Waals interaction found in other synthetic polymers and fibers like dyneema. The presence of salts and certain other impurities, especially calcium, would interfere with the strand interactions and has to be avoided in the production process. Kevlar consists of relatively rigid molecules, which form a planar sheet-like structure similar to silk protein.

These properties result in its high mechanical strength and its remarkable heat resistance. Because it is highly unsaturated, i.e. the ratio of carbon to hydrogen atoms is quite high, it has a low flammability.
Kevlar molecules have polar groups accessible for hydrogen bonding. Water that enters the interior of the fiber can take the place of bonding between molecules and reduce the material's strength, while the available groups at the surface lead to good wetting properties. This is important for bonding the fibers to other types of polymer, forming a fibre reinforced plastic. This same property also makes the fibers feel more natural and "sticky" compared to non-polar polymers like polyethylene.

Production of Kevlar

Kevlar is synthesized from the monomers 1,4-phenyl-diamine (para-phenylenediamine) and terephthaloyl chloride. The result is a polymeric aromatic amide (aramid) with alternating benzene rings and amide groups. When they are produced, these polymer strands are aligned randomly. To make Kevlar, they are dissolved and spun, causing the polymer chains to orient in the direction of the fiber. 

 

Kevlar has a high price at least partly because of the difficulties caused by the use of concentrated sulfuric acid in its manufacture. These harsh conditions are needed to keep the highly insoluble polymer in The chemical synthesis of kevlar from 1,4-phenyl-diamine (para-phenylenediamine) and terephthaloyl chlorid.

Acrylic Fiber

Acrylic fibers are synthetic fibers made from a polymer (Polyacrylonitrile) with an average molecular weight of 100,000, about 1900 monomer units. To be called acrylic in the U.S, the polymer must contain at least 85% acrylonitrile monomer. Typical comonomers are vinyl acetate or methyl acrylate.

Production of Acrylic

The polymer is formed by free-radical polymerization in aqueous suspension. The fiber is produced by dissolving the polymer in a solvent such as N,N-dimethylformamide or aqueous sodium thiocyanate, metering it through a multi-hole spinnerette and coagulating the resultant filaments in an aqueous solution of the same solvent (wet spinning) or evaporating the solvent in a stream of heated inert gas (dry spinning). Washing, stretching, drying and crimping complete the processing. Acrylic fibers are produced in a range of deniers, typically from 1 to 15 as cut staple or as a 500,000 to 1 million filament tow. End uses include sweaters, hand-knitting yarns, rugs, awnings, boat covers, and upholstery; the fiber is also used as a precursor for carbon fiber. Production of acrylic fibers is centered in the Far East, declining in Europe and now shut down (except for precursor) in the U.S. Former U.S. brands of acrylic were Acrilan (Monsanto). Creslan (American Cyanamid) and Orlon (DuPont).

Textile Uses of Acrylic

Acrylic is lightweight, soft, and warm, with a wool-like feel. It dyes very well and has excellent colorfastness. It is resilient, retains its shape, and resists shrinkage and wrinklesAcrylic has recently been used in clothing as a less expensive alternative to cashmere, due to the similar feeling of the materials. The disadvantages of acrylic is that it tends to fuzz (or pill) easily and that it does not insulate the wearer as well as cashmere. Many products like fake pashmina or cashmina use this material to create the illusion of cashmere to the consumer. Acrylic is resistant to moths, oils, and chemicals, and is very resistant to deterioration from sunlight exposure. However, static and pilling can be a problem. Acrylic fiber is a synthetic polymer fiber that contains at least 85% acrylonitrile.

Synthetic Fibers

Synthetic fibers are the result of extensive research by scientists to improve upon naturally occurring animal and plant fibers. In general, synthetic fibers are created by forcing, usually through extrusion, fiber forming materials through holes (called spinnerets) into the air, forming a thread. Before synthetic fibers were developed, artificially manufactured fibers were made from cellulose, which comes from plants. These fibers are called cellulose fibers.

The first artificial fiber, known as artificial silk, became known as viscose around 1894, and finally rayon in 1924. A similar product known as cellulose acetate was discovered in 1865. Rayon and acetate are both artificial fibers, but not truly synthetic, being made from wood. Although these artificial fibers were discovered in the mid-nineteenth century, successful modern manufacture began much later (see the dates below). Nylon, the first synthetic fiber, made its debut in the United States as a replacement for silk, just in time for World War II rationing. Its novel use as a material for women's stockings overshadowed more practical uses, such as a replacement for the silk in parachutes and other military uses.

Common Synthetic Fibers include :

• Rayon (1910) (artificial, not synthetic)

• Acetate (1924) (artificial, not synthetic)

• Nylon (1939)

• Modacrylic (1949)

• Olefin (1949)

• Acrylic (1950)

• Polyester (1953)

• Carbon fiber (1968)

Specialty Synthetic Fibers include :

• Vinyon (1939)

• Saran (1941)

• Spandex (1959)

• Vinalon (1939)

• Aramids (1961) - known as Nomex, Kevlar and Twaron

• Modal (1960's)

• Dyneema/Spectra (1979)

• PBI (Polybenzimidazole fiber) (1983)

Asbestos Fiber

Asbestos , the fibrous form of several minerals and hydrous silicates of magnesium. The name may also be applied to the fibrous forms of calcium and iron. Asbestos fibers can be molded or woven into various fabrics. Because it is nonflammable and a poor heat conductor, asbestos has been widely used to make fireproof products such as safety clothing for fire fighters and insulation products such as hot-water piping. The first recorded use of the word asbestos is by Pliny the Elder in the 1st century ad, although the substance itself was known as early as the 2nd century bc. The Romans made cremation cloths and wicks from it, and centuries later Marco Polo noted its usefulness as cloth.

Asbestos is of two principal classes, the amphiboles and the serpentines, the former of relatively minor importance. Chrysotile, in the serpentine class, constitutes most of the world supply of asbestos. Countries that have produced asbestos include Russia, Kazakhstan, China, Brazil, and Canada.

Asbestos is obtainable by various underground mining methods, but the most common method is open-pit mining. Only about 6 percent of the mined ore contains usable fibers.

The fibers are separated from the ore by crushing, air suction, and vibrating screens, and in the process are sorted into different lengths, or grades. The most widely used method of grading, the Québec Standard Test Method, divides the fibers into seven groups, the longest in group one and the shortest, called milled asbestos, in group seven. The length of the fibers, as well as the chemical composition of the ore, determines the kind of product that can be made from the asbestos. The longer fibers have been used in fabrics, commonly with cotton or rayon, and the shorter ones for molded goods, such as pipes and gaskets.

Asbestos has been used in building-construction materials, textiles, missile and jet parts, asphalt and caulking compounds and paints, and in friction products such as brake linings. Exposure to asbestos fibers and dust, however, can cause asbestosis, a disease of the lungs caused by the inhalation of asbestos particles, and, after a latent period of up to 30 years and more, various cancers, especially lung cancer and mesothelioma, which is an inoperable cancer of the chest and abdominal lining . At present no wholly satisfactory substitutes are available for asbestos in many of its applications; because of health risks posed by asbestos use, however, research into replacements has been accelerated. In 1986 the Environmental Protection Agency proposed an immediate ban on the major uses of asbestos and a complete ban on all asbestos products within the next decade.

Quartz Fiber

Quartz, second most common of all minerals in Earth's crust after feldspar. Quartz is composed of silicon dioxide, or silica, SiO2. It is distributed all over the world as a constituent of rocks and in the form of pure deposits. It is an essential constituent of igneous rocks such as granite, rhyolite, and pegmatite, which contain an excess of silica. In metamorphic rocks, it is a major constituent of the various forms of gneiss and schist; the metamorphic rock quartzite is composed almost entirely of quartz. Quartz forms veins and nodules in sedimentary rock, principally limestone. Sandstone, a sedimentary rock, is composed mainly of quartz. Many widespread veins of quartz deposited in rock fissures form the matrix for many valuable minerals. Precious metals, such as gold, are found in sufficient quantity in quartz veins to warrant the mining of quartz to recover the precious mineral. Quartz is also the primary constituent of sand.

Properties of Quartz

Quartz crystallizes in the rhombohedral system, with six faces each shaped like a rhombus. The size of the crystals varies from specimens weighing a metric ton to minute particles that sparkle in rock surfaces. Quartz is also common in massive forms, which contain particles ranging in size from coarse-grained to cryptocrystalline (grains invisible to the naked eye but observable under a microscope). The mineral has a hardness of 7 and specific gravity of 2.65. The luster in some specimens is vitreous; in others it is greasy or splendent (shining glossily). Some specimens are transparent; others are translucent. In the pure form, the mineral is colorless, but it is commonly colored by impurities.

Quartz crystals exhibit a property called the piezoelectric effect, that is, they produce an electric voltage when subjected to pressure along certain directions of the crystal. Because of this property, quartz crystal has had important applications in the electronics industry, including controlling the frequency of radio waves. It also has the optical property of rotating the plane of polarized light and has been used in polarizing microscopes.
Quartz crystals undergo structural transformations when heated. Ordinary, or low, quartz, when heated to 573°C (1063.4°F), is converted into high quartz, which has a different crystal structure and different physical properties. When cooled, however, high quartz reverts to low quartz. Between 870° and 1470°C (1598° and 2678°F), quartz exists in the form called tridymite, and above 1470°C (2678°F), the stable form is known as cristobalite. At about 1710°C (3078°F), the mineral melts.

Uses Of Quartz

The different forms of chalcedony and many of the crystalline varieties of quartz are used as gemstones and other ornamental materials. Pure rock crystal is used in optical and electronic equipment. In the form of sand, quartz is used extensively in the manufacture of glass and silica brick, and is also used in cement and mortar. Ground quartz is used as an abrasive in stonecutting, sandblasting, and glass grinding. Powdered quartz has been used in making porcelain, scouring soaps, sandpaper, and wood fillers. Large amounts of quartz have been used as a flux in smelting operations. Natural high-grade quartz crystal has been an important raw material in the electronics industry. Quartz crystals can also be made synthetically.

Glass Fiber

Fiberglass, (also called fiberglass and glass fiber), is material made from extremely fine fibers of glass. It is used as a reinforcing agent for many polymer products; the resulting composite material, properly known as fiber-reinforced polymer (FRP) or glass-reinforced plastic (GRP), is called "fiberglass" in popular usage. Glassmakers throughout history have experimented with glass fibers, but mass manufacture of fiberglass was only made possible with the invention of finer machine tooling. In 1893, Edward Drummond Libbey exhibited a dress at the World's Columbian Exposition incorporating glass fibers with the diameter and texture of silk fibers. This was first worn by the popular stage actress of the time Georgia Cayvan.

The Nature of Glass

Glass is typically viewed as an elastic solid in which no significant crystallization has occurred. Thus there is no long-range ordering or extended formation of any Bravais lattice. It follows that glass, even as a fiber, has little crystalline structure (see amorphous solid). The properties of the structure of glass in its softened stage are very much like its properties when spun into fiber. One definition of glass is "an inorganic substance in a condition which is continuous with, and analogous to the liquid state of that substance, but which, as a result of a reversible change in viscosity during cooling, has attained so high a degree of viscosity as to be, for all practical purposes, rigid."

Generally speaking, the atomic or molecular structure of glass exists in a metastable state with respect to its crystalline form. This essentially reflects their formation from a non-equilibrium supercooled liquid state. Fundamental principles of Gibbs free energy minimization dictate this thermodynamic driving force towards crystallinity, long-range symmetry and thermodynamic equilibrium. 

Types of Fiber Glass

Two types of fiberglass are most commonly used.

They are S-glass and E-glass.

• E-glass has good insulation properties and it will maintain its properties up to 1500 degree F(815 deg C).

• S-glass has a high tensile strength and is stiffer than E-glass. 

Properties of Glass

Glass fibers are useful because of their high ratio of surface area to weight. However, the increased surface area makes them much more susceptible to chemical attack. By trapping air within them, blocks of glass fiber make good thermal insulation, with a thermal conductivity of the order of 0.05 W/(mK).

The strength of glass is usually tested and reported for "virgin" or pristine fibers -- those which have just been manufactured. The freshest, thinnest fibers are the strongest because the thinner fibers are more ductile. The more the surface is scratched, the less the resulting tenacity. Because glass has an amorphous structure, its properties are the same along the fiber and across the fiber. Humidity is an important factor in the tensile strength. Moisture is easily adsorbed, and can worsen microscopic cracks and surface defects, and lessen tenacity.

In contrast to carbon fiber, glass can undergo more elongation before it breaks. There is a correlation between bending diameter of the filament and the filament diameter. The viscosity of the molten glass is very important for manufacturing success. During drawing (pulling of the glass to reduce fiber circumference), the viscosity should be relatively low. If it is too high, the fiber will break during drawing. However, if it is too low, the glass will form droplets rather than drawing out into fiber.

Uses of Glass

Uses for regular fiberglass include mats, thermal insulation, electrical insulation, reinforcement of various materials, tent poles, sound absorption, heat- and corrosion-resistant fabrics, high-strength fabrics, arrows, bows and crossbows, translucent roofing panels, automobile bodies, electrical insulation and boat hulls.

Mineral Fibers

Mineral fibers comprise asbestos. Asbestos is the only naturally occurring long mineral fiber. Short, fiber-like minerals include wollastonite, attapulgite and halloysite.

Other Mineral Fibers Include Glass Fiber and Quartz.

Marino Wool Fiber

The Merino is the most economically influential breed of sheep in the world, prized for its wool. Super fine Merinos are regarded as having the finest and softest wool of any sheep. Recently the low price of wool has led to more emphasis on the market and sale of the animal's meat. Poll Merinos have no horns (or very small stubs, known as scurs), and horned Merino rams have long, spiral horns which grow close to the head.

Characteristics of Marino Wool Fiber

The Merino is an excellent forager and very adaptable. It is bred predominantly for its wool, and its carcase size is generally smaller than that of sheep bred for meat. The South African Meat Merino (SAMM) and merinofleischschaf have been bred to balance wool production and carcase quality. Merino wool is finely crimped and soft. Staples are commonly 2.5-4 inches (65-100 mm) long. A Saxon Merino produces 3 to 6 kg of greasy wool a year while a good quality Peppin Merino ram produces up to 18 kg. Merino wool is generally less than 24 micron (µm) in diameter. Basic Merino types include: strong (broad) wool 23-24.5 µm, medium wool is 19.6-22.9 µm, fine 18.6-19.5 µm, superfine 15-18.5 µm and ultra fine 11.5-15 µm. Ultra fine wool is suitable for blending with other exclusive fibres such as silk and cashmere. New Zealand retails luxury, lightweight knits made from Merino wool and possum fur.

The term merino is widely used in the textile industries with very varied meanings. Originally it denoted the wool of Merino sheep reared in Spain, but due to the superiority of Australian and New Zealand wools the term now has broader use. In the dress-goods and knitting trades the term "Merino" still implies an article made from the very best soft wool.

Regions of Merino Husbandry

In Argentina, Australia, New Zealand, South Africa and the western United States where sheep are bred for their wool rather than their mutton, Merino sheep dominate. Australia produces about 80% of the world's Merino wool. In Australia and New Zealand Merino ewes are crossed with Border Leicesters and other English long wool breeds to produce first cross prime lamb mothers and prime lamb wethers. The prime lamb mothers are crossed again with Poll Dorsets and other short wool breeds and the resultant second cross lambs slaughtered as prime lambs.

Llama Fiber

Llamas also have a fine undercoat which can be used for handicrafts and garments. The coarser outer guard hair is used for rugs, wall-hangings and lead ropes. The fiber comes in many different colors ranging from white, grey, redish brown, brown, dark brown and black.

The individual shafts of the wool can be measured in micrometres.
1 micrometre = 1/1000 millimeter.

Technically the fiber is not wool as it is hollow with a structure of diagonal 'walls' which makes it strong, light and good insulation. Wool as a word by itself refers to sheep fiber. However, llama fiber is commonly referred to as llama wool or llama fiber.

The llama (Lama glama) is a South American camelid, widely used as a pack animal by the Incas and other natives of the Andes mountains. In South America llamas are still used as beasts of burden, as well as for the
production of fiber and meat.

The height of a full-grown, full-size llama is between 5.5 feet (1.6 meters) to 6 feet (1.8 m) tall at the top of the head. They can weigh between approximately 280 pounds (127 kilograms) and 450 pounds (204 kilograms). At birth, a baby llama (called a cria) can weigh between 20 pounds (9 kilograms) to 30 pounds (14 kilograms). Llamas are very social animals and like to live with other llamas as a herd. Overall, the fiber produced by a llama is very soft and is naturally lanolin free. Llamas are intelligent and can learn simple tasks after a few repetitions. When using a pack, llamas can carry about 25%-30% of their body weight for several miles.

Llamas appear to have originated from the central plains of North America about 40 million years ago. They migrated to South America and Asia about 3 million years ago. By the end of the last ice age (10,000-12,000 years ago) camelids were extinct in North America.As of 2007, there were over 7 million llamas and alpacas in South America and, due to importation from South America in the late 20th century, there are now over 100,000 llamas and 6,500-7,000 alpacas in the US and Canada.

Cashmere Fiber

Classification : Hair fibre Primary
Uses : Men's and women's coats, jackets and blazers, skirts, hosiery, sweaters, gloves, scarves, mufflers, caps and robes.

General Characteristics : Luxuriously soft, with high napability and loft; provides natural light-weight insulation without bulk. Cashmere is extremely warm (in order to serve its original purpose of protecting goats from cold mountain temperatures.) Fibres are highly adaptable and are easily constructed into fine or thick yarns, and light to heavy-weight fabrics. Appropriate for all climates. A high moisture content allows insulation properties to change with the relative humidity in the air.

Source : The Cashmere (Kashmir) or down goat. From the fine, soft undercoat or underlayer of hair. The straighter and coarser outer coat is called guard hair.

Geographic Origin : From the high plateaus of Asia. Significant supplier countries are: China, Mongolia and Tibet. Today, little is supplied by the Kashmir State of India, from which its name is derived. The cashmere products of this area first attracted the attention of Europeans in the early 1800's.

Gathering Process : The specialty animal hair fibres are collected during molting seasons when the animals naturally shed their hairs. Goats molt during a several-week period in spring. In China and Mongolia, the down is removed by hand with a coarse comb. The animals are sheared in Iran, Afghanistan, New Zealand and Australia.

Production : The coarse hairs and down hairs of the cashmere goat and camel are separated by a mechanical process known as dehairing.

Annual Yield : Up to half a kilo of fibre per goat, with an average 150 gram of underdown.

Natural Colors : Gray, brown and white.

Angora Wool

Angora wool or Angora fiber refers to the downy coat produced by the Angora rabbit. While their names are similar, Angora fiber is distinct from mohair, which comes from the Angora goat. Angora is known for its softness, low micron count (i.e. thin fibers), and what knitters refer to as a halo (fluffiness). It is also known for its silky texture.

Angora rabbits produce coats in a variety of colors, from white to black. Good quality angora fiber is around 12-16 microns in diameter, and can cost around 10 - 16 dollars per ounce. It felts very easily, even on the animal itself if the animal is not groomed frequently.

The fiber is normally blended with wool to give the yarn elasticity, as angora fiber is not naturally elastic. The blend decreases the softness and halo as well as the price of the finished object.

The Angora Rabbit

There are four different ARBA recognized types of Angora rabbit: English, French, Satin and Giant. There are many other breeds, one of the more common being German. Each breed produces different quality and quantity of fiber, and has a different range of colors.

 

Fur Production

Angora fur is produced in Europe, Chile, China and the United States. Harvesting occurs up to four times a year (about every 4 months) and is collected by plucking, shearing, or collection of the molting fur.

Most breeds of Angora rabbits molt with their natural growth cycle about every four months. Many producers of the fiber pluck the fur of these breeds. Plucking is, in effect, pulling out the molted fur. Plucking ensures a minimum of guard hair, and the fur is not as matted when plucked as when it is collected from the rabbit's cage. However, plucking a rabbit is time consuming, so some producers shear the rabbit instead. While this results in slightly lower quality fleece as the guard hairs are included, it does take less time and results in more fleece. Also, not all breeds of angora molt, and if the rabbit does not naturally molt, it cannot be plucked. German angoras do not molt.
The rabbits must be groomed at least once or twice a week to prevent the fur from matting and felting. There is also a danger that a rabbit will ingest its own molted fur; unlike a cat, a rabbit cannot easily be rid of the build up.

Alpaca Fiber

Alpaca fleece is the natural fiber harvested from an Alpaca. It is a light-weight, soft, durable, luxurious and silky natural fiber. While similar to sheep's wool in that it is a natural fiber, it is warmer, not prickly, and has no lanolin which makes it hypoallergenic. However, this lack of lanolin also prevents Alpaca fiber from being naturally water-repellent. It also has less crimp, thus making it much less elastic. Alpaca fleece is made into various exports, from very simple and inexpensive garments made by the aboriginal communities to sophisticated, industrially made and expensive products such as suits.

History of Alpacas

Alpaca have been bred in South America for thousands of years. Vicuñas were first domesticated and bred into alpacas by the ancient Andean tribes of Peru, but also appeared in Chile and Bolivia. In recent years alpacas have also been exported to other countries. In countries such as the USA, Australia and New Zealand breeders shear their animals annually, weigh the fleeces and test them for fineness. With the resulting knowledge they are able to breed heavier-fleeced animals with finer fiber. Fleece weights vary, with the top stud males reaching annual shear weights up to 7 kg total fleece and 3 kg good quality fleece. The discrepancy in weight is because an alpaca has guard hair which is often removed before spinning.

 

Types of Alpacas
There are two types of Alpaca: Huacaya (which produce a dense, soft, crimpy sheep-like fiber), Mop-like Suri (with silky pencil-like locks, resembling dread-locks but not actually matted fibers). Suris are prized for their longer and silkier fibers, and estimated to make up between 19-20% of the Alpaca population. Since its import into the United States, the number of Suri alpacas has grown substantially and become more color diverse. The Suri is thought to be rarer, possibly because it is less hardy in the harsh South American mountain climates, as its fleece offers less insulation against the cold.

By-Products of Wool

The use of waste is very important to the wool industry. Attention to this aspect of the business has a direct impact on profits.
These wastes are grouped into four classes:

Noils

These are the short fibers that are separated from the long wool in the combing process. Because of their excellent condition, they are equal in quality to virgin wool. They constitute one of the major sources of waste in the industry and are reused in high-quality products.

 

Soft Waste

This is also high-quality material that falls out during the spinning and carding stages of production. This material is usually reintroduced into the process from which it came.

 

Hard Waste

These wastes are generated by spinning, twisting, winding, and warping. This material requires much re-processing and is therefore considered to be of lesser value.

Finishing Waste

This category includes a wide variety of clippings, short ends, sample runs, and defects. Since this material is so varied, it requires a great deal of sorting and cleaning to retrieve that which is usable. Consequently, this material is the lowest grade of waste.

Manufacturing of Wool

The major steps necessary to process wool from the sheep to the fabric are: shearing, cleaning and scouring, grading and sorting, carding, spinning, weaving, and finishing.

Shearing

Sheep are sheared once a year-usually in the springtime. A veteran shearer can shear up to two hundred sheep per day. The fleece recovered from a sheep can weigh between 6 and 18 pounds (2.7 and 8.1 kilograms); as much as possible, the fleece is kept in one piece. While most sheep are still sheared by hand, new technologies have been developed that use computers and sensitive, robot-controlled arms to do the clipping

Grading and Sorting

Grading is the breaking up of the fleece based on overall quality. In sorting, the wool is broken up into sections of different quality fibers, from different parts of the body. The best quality of wool comes from the shoulders and sides of the sheep and is used for clothing; the lesser quality comes from the lower legs and is used to make rugs. In wool grading, high quality does not always mean high durability.

Cleaning and Scouring

Wool taken directly from the sheep is called "raw" or "grease wool." It contains sand, dirt, grease, and dried sweat (called suint); the weight of contaminants accounts for about 30 to 70 percent of the fleece's total weight. To remove these contaminants, the wool is scoured in a series of alkaline baths containing water, soap, and soda ash or a similar alkali. The byproducts from this process (such as lanolin) are saved and used in a variety of household products. Rollers in the scouring machines squeeze excess water from the fleece, but the fleece is not allowed to dry completely. Following this process, the wool is often treated with oil to give it increased manageability. 

 

Carding

Next, the fibers are passed through a series of metal teeth that straighten and blend them into slivers. Carding also removes residual dirt and other matter left in the fibers. Carded wool intended for worsted yarn is put through gilling and combing, two procedures that remove short fibers and place the longer fibers parallel to each other. From there, the sleeker slivers are compacted and thinned through a process called drawing. Carded wool to be used for woolen yarn is sent directly for spinning.

Spinning

Thread is formed by spinning the fibers together to form one strand of yarn; the strand is spun with two, three, or four other strands. Since the fibers cling and stick to one another, it is fairly easy to join, extend, and spin wool into yarn. Spinning for woolen yarns is typically done on a mule spinning machine, while worsted yarns can be spun on any number of spinning machines. After the yarn is spun, it is wrapped around bobbins, cones, or commercial drums. 

 

Weaving

Next, the wool yarn is woven into fabric. Wool manufacturers use two basic weaves: the plain weave and the twill. Woolen yarns are made into fabric using a plain weave (rarely a twill), which produces a fabric of a somewhat looser weave and a soft surface (due to napping) with little or no luster. The napping often conceals flaws in construction. Worsted yarns can create fine fabrics with exquisite patterns using a twill weave. The result is a more tightly woven, smooth fabric. Better constructed, worsteds are more durable than woolens and therefore more costly.

Finishing

After weaving, both worsteds and woolens undergo a series of finishing procedures including:

• Fulling (immersing the fabric in water to make the fibers interlock)

• Crabbing (permanently setting the interlock)

• Decating (shrink-proofing)

• Occasionally, dyeing.
  

Although wool fibers can be dyed before the carding process, dyeing can also be done after the wool has been woven into fabric.

Wool Fiber

Wool is the fiber derived from the hair of domesticated animals, usually sheep.

History of Wool As the raw material has been readily available since the widespread domestication of sheep and similar animals, the use of wool for clothing and other fabrics dates back to some of the earliest civilizations. Prior to invention of shears - probably in the Iron Age - they probably plucked the wool out by hand or by bronze combs.

In medieval times, the wool trade was serious business. English wool exports - which bordered on European monopoly - were a significant source of income to the crown. Over the centuries, various British laws controlled the wool trade or required the use of wool even in burials. In 1699 English crown forbade its American colonies to trade wool with anyone else but the England itself.

Australia and New Zealand are leading commercial producers of wool. Most of the wool comes from the Merino breed of sheep when breeds of Lincoln and Romney produce coarser fibers that are usually used for making carpets. In the United States, Texas, New Mexico and Colorado also have large commercial sheep flocks and their mainstay is the Rambouillet, or French Merino. There is also a thriving 'home flock' contigent of small scale farmers who raise small hobby flocks of specialty sheep for the handspinning market. These small scale farmers may raise any type of sheep they wish, so the selection of fleeces is quite wide.

Processing of Wool
Wool straight off a sheep contains a high level of grease which contains valuable lanolin, as well as dirt, dead skin, sweat residue, and vegetable matter. This state is known as "grease wool" or "wool in the grease". Before the wool can be used for commercial purposes it must be scoured, or cleaned. Scouring may be as simple as a bath in warm water, or a complicated industrial process using detergent and alkali. In commercial wool, vegetable matter is often removed by the chemical process of chemical carbonization. In less processed wools, vegetable matter may be removed by hand, and some of the lanolin left intact through use of gentler detergents. This semi-grease wool can be worked into yarn and knitted into particularly water-resistant mittens or sweaters, such as those of the Aran Island fishermen. Lanolin removed from wool is widely used in the cosmetics industry, such as hand creams.
After shearing, the wool is separated into five main categories: fleece (which makes up the vast bulk), broken, pieces, bellies and locks. The latter four are pressed into wool packs and sold separately. The quality of fleece is determined by a technique known as wool classing, whereby a qualified woolclasser groups wools of similar gradings together to maximise the return for the farmer or sheep owner. Prior to Australian auctions all Merino fleece wool is objectively measured for micron, yield (including the amount of vegetable matter), staple length, staple strength and sometimes color and comfort factor.

Silk Fiber

Silk.is a natural fiber that can be woven into textiles. It is obtained from the cocoon of the silkworm larva, in the process known as sericulture, which kills the larvae.

Silk was first developed in early China, possibly as early as 6000 BC and definitely by 3000 BC. Legend gives credit to a Chinese Empress Xi Ling Shi. Though first reserved for the Emperors of China, its use spread gradually through Chinese culture both geographically and socially. From there, silken garments began to reach regions throughout Asia. Silk rapidly became a popular luxury fabric in the many areas accessible to Chinese merchants, because of its texture and lustre. Because of the high demand for the fabric, silk was one of the staples of international trade prior to industrialization.

Perhaps the first evidence of the silk trade is that of an Egyptian mummy of 1070 BC. In subsequent centuries, the silk trade reached as far as the Indian subcontinent, the Middle East, Europe, and North Africa. This trade was so extensive that the major set of trade routes between Europe and Asia has become known as the Silk Road.

Uses of Silk

Silk's good absorbency makes it comfortable to wear in warm weather and while active. Its low conductivity keeps warm air close to the skin during cold weather. It is often used for clothing such as shirts, blouses, formal dresses, high fashion clothes, negligees, pyjamas, robes, skirtsuits, sun dresses and underwear.

Silk's elegant, soft luster and beautiful drape makes it perfect for many furnishing applications. It is used for upholstery, wall coverings, window treatments (if blended with another fiber), rugs, bedding and wall hangings

While on the decline now, due to artificial fibers, silk has had many uses; parachutes, bicycle tires, comforter filling and artillery gunpowder bagsFrom the blackpowder era, until roughly World War I, early bulletproof vests were made from silk

A special manufacturing process which removes the outer irritant sericin coating of the silk makes it suitable as non-absorbable surgical sutures. This process has also recently led to the introduction of specialist silk underclothing for children and adults with eczema where it can significantly reduce itch

Silk cloth is also used as a material on which to write and paint.

 

Physical Properties of Silk

Silk fibers have a triangular cross section with rounded corners. This reflects light at many different angles, giving silk a natural shine. It has a smooth, soft texture that is not slippery, unlike many synthetic fibers. Its denier is 4.5 g/d when dry and 2.8-4.0 g/d when moist.

Silk is one of the strongest natural fibers but loses up to 20% of its strength when wet. It has a good moisture regain of 11%. Its elasticity is moderate to poor: if elongated even a small amount it remains stretched. It can be weakened if exposed to too much sunlight. It may also be attacked by insects, especially if left dirty.

Silk is a poor conductor of electricity and thus susceptible to static cling.

Unwashed silk chiffon may shrink up to 8% due to a relaxation of the fiber macrostructure. So silk should either be pre-washed prior to garment construction, or dry cleaned. Dry cleaning may still shrink the chiffon up to 4%. Occasionally, this shrinkage can be reversed by a gentle steaming with a press cloth. There is almost no gradual shrinkage or shrinkage due to molecular-level deformation.

 

Chemical Properties of Silk

Silk is made up of the amino acids GLY-SER-GLY-ALA-GLY and forms Beta pleated sheets. Interchain H-bonds are formed while side chains are above and below the plane of the H-bond network.

The high proportion (50%) of glycine, which is small, allows tight packing and the fibers are strong and resistant to stretching. The tensile strength is due to covalent peptide bonds. Since the protein forms a Beta sheet, when stretched the force is applied to these strong bonds and they do not break.

Silk is resistant to most mineral acids but will dissolve in sulfuric acid. It is yellowed by perspiration.

Cultivation of Silk

Silk moths lay eggs on specially prepared paper. The eggs hatch and the caterpillars (silkworms) are fed fresh mulberry leaves. After about 35 days and 4 moltings, the caterpillars are 10,000 times heavier than when hatched, and are ready to begin spinning a cocoon. A straw frame is placed over the tray of caterpillars, and each caterpillar begins spinning a cocoon by moving its head in a "figure 8" pattern. Two glands produce liquid silk and force it through openings in the head called spinnerets. Liquid silk is coated in sericin, a water-soluble protective gum, and solidifies on contact with the air. Within 2-3 days, the caterpillar spins about 1 mile of filament and is completely encased in a cocoon. The silk farmers then kill most caterpillars by heat, leaving some to metamorphose into moths to breed the next generation of caterpillars.

Animal Fibers

Animal fibers are natural fibers that consist largely of particular proteins. Instances are silk, hair/fur (including wool) and feathers. The animal fibers used most commonly both in the manufacturing world as well as by the hand spinners are wool from domestic sheep and silk. Also very popular are alpaca fiber and mohair from Angora goats. Unusual fibers such as Angora wool from rabbits and Chiengora from dogs also exist, but are rarely used for mass production.

Not all animal fibers have the same properties, and even within a species the fiber is not consistent. Merino is a very soft, fine wool, while Cotswold is coarser, and yet both merino and Cotswold are types of sheep. This comparison can be continued on the microscopic level, comparing the diameter and structure of the fiber. With animal fibers, and natural fibers in general, the individual fibers look different, whereas all synthetic fibers look the same. This provides an easy way to differentiate between natural and synthetic fibers under a microscope.

Soybean Fiber

As early as 1937 soybean fiber was showing promise of usefulness in the textile field. It was the first textile filament to be spun from the protein of vegetable origin. Soybean is exceptionally rich in protein, nearly 50% is protein.

Initially the fiber was manufactured by crushing beans under pressure and extracting oil. The protein in turn was extracted by passing the meal through a saline solution; it was then combined with various chemicals to form a liquid about as thick as molasses to be used in a spinning solution. This was forced through a spinneret containing as many as 500 holes and the filaments were then hardened in an acid bath.

Early soybean fiber research was a problem for scientists who were unable to produce firm, tough protein filaments which would resist wear and deterioration. This was due to a molecular arrangement very different from the structure of natural fibers.

The fiber was white to light tan color and had the appearance and texture similar to wool and silk, was warm and soft to the feel, had natural crimp and a high degree of resiliency. It did not absorb moisture as easily as wool or casein and thus didn't mold as readily as casein fiber. Because its chemical properties were similar to wool it could be dyed the same as wool.

It blended well with wool, rayon and cotton and was woven and knitted into goods by the usual textile methods. Ford Motor company experimented with it for car seats in the early 1940s which proved to be quite satisfactory. Fiber was used also for suitings and other upholstery fabrics but there was never any major production.

Bamboo Fiber

Three to four years old green bamboo is used to produce natural and eco-friendly fiber without any chemical additives.

The bamboo fiber fabric production flow is:Bamboo-Thick pulp-Fine pulp-Bamboo fiber-Bamboo yarn-Fabric

Bamboo pulp is refined from bamboo through a process of hydrolysis-alkalization and multi-phase bleaching. After which, bamboo pulp is processed into bamboo fiber. Repeated tests have proven that bamboo fiber has strong durability, stability, and tenacity. The thinness and whiteness of bamboo fiber is similar to classic viscose. Moreover, because of the bamboo fiber's abrasion-proof capacity, it spins nicely from bamboo fibers are now being exported to Europe.

Linen Fiber

It is strong, durable, and resists rotting in damp climates. It is one of the few textiles that has a greater breaking strength wet than dry. It has a long "staple" (individual strand length) relative to cotton and other natural fibers.

Production History of Linen

Up until the 1950's or so the finest linen yarn was made in Scotland, Ireland, and Belgium. The climates of these locations were ideal for natural processing methods called "retting". As years went by many of the finest factories in those areas closed, and most linen is currently made in China.

The decrease in use of linen may be attributed to the increasing quality of synthetic fibers, and a decreasing appreciation of buyers for very high quality yarn and fabric. Very little top-quality linen is produced now, and most is used in low volume applications like hand weaving and as an art material.

Uses of Linen

Linen is also used for cloth, canvases, sails, tents, and paper. Due to its one-time common use to make fine fabric, "linens" became the generic term for sheets and pillowcases, although these are now often made of cotton or synthetic fibers

Due to its strength, in the Middle Ages linen was used for shields and gambesons, but also for underwear and other clothing's.

Cotton Fiber

Cotton is a soft fiber that grows around the seeds of the cotton plant . The fiber is most often spun into thread and used to make a soft, breathable textile.

Cotton is a valuable crop because only about 10% of the raw weight is lost in processing. Once traces of wax, protein, etc. are removed, the remainder is a natural polymer of pure cellulose. This cellulose is arranged in a way that gives cotton unique properties of strength, durability, and absorbency. Each fiber is made up of twenty to thirty layers of cellulose coiled in a neat series of natural springs. When the cotton boll (seed case) is opened the fibres dry into flat, twisted, ribbon-like shapes and become kinked together and interlocked. This interlocked form is ideal for spinning into a fine yarn.

History of Cotton

Cotton has been used to make very fine lightweight cloth in areas with tropical climates for millennia. Some authorities claim that it was likely that the Egyptians had cotton as early as 12,000 BC, and they have found evidence of cotton in Mexican caves (cotton cloth and fragments of fiber interwoven with feathers and fur) which dated back to approximately 7,000 years ago. There is archaeological evidence that people in South America and India domesticated independently different species of the cotton plant thousands of years ago. 

 

Production of Cotton

Today cotton is produced in many parts of the world, including Europe, Asia, Africa, the Americas and Australia, using cotton plants that have been selectively bred so that each plant grows more fiber. In 2002, cotton was grown on 330,000 km² of farmland. 47 billion pounds (21 million t) of raw cotton worth 20 billion dollars US was grown that year.

Sisal Fiber

Sisal plants consist of a rosette of sword-shaped leaves about 1.5 to 2 meters tall. Young leaves may have a few minute teeth along their margins, but lose them as they mature. Sisals are sterile hybrids of uncertain origin; although shipped from the port of Sisal in Yucatán (thus the name), they do not actually grow in Yucatán, the plantations there cultivate henequen (Agave fourcroydes) instead. Evidence of an indigenous cottage industry in Chiapas suggests it as the original location, possibly as a cross of Agave angustifolia and Agave kewensis.

The sisal plant has a 7-10 year life-span and typically produces 200-250 commercially usable leaves. Each leaf contains an average of around 1000 fibers. The fibers account for only about 4% of the plant by weight. Sisal is considered a plant of the tropics and subtropics, since production benefits from temperatures above 25 degrees Celsius and sunshine.

Uses of Sisal

Traditionally, sisal has been the leading material for agricultural twine (binder twine and baler twine) because of its strength, durability, ability to stretch, affinity for certain dyestuffs, and resistance to deterioration in saltwater. but the importance of this traditional use is diminishing with competition from polypropylene and the development of other haymaking techniques, while new higher-valued sisal products have been developed. Apart from ropes, twines and general cordage sisal is used in low-cost and specialty paper, dartboards, buffing cloth, filters, geotextiles, mattresses, carpets, handicrafts, wire rope cores and Macrame. In recent years sisal has been utilized as an environmentally friendly strengthening agent to replace asbestos and fiberglass in composite materials in various uses including the automobile industry.. The lower grade fiber is processed by the paper industry because of its high content of cellulose and hemicelluloses. The medium grade fiber is used in the cordage industry for making: ropes, baler and binders twine. Ropes and twines are widely employed for marine, agricultural, and general industrial use. The higher-grade fiber after treatment is converted into yarns and used by the carpet industry.

Coir Fiber

Coir is a coarse fiber obtained from the tissues surrounding the seed of the coconut palm, Cocos nucifera. The intact fruit has a smooth leathery skin above the thick fibrous layer. This surrounds the stony dark brown shell, which is actually part of the fruit rather than the seed. Inside the shell are the papery brown outer layer of the seed surrounding the nutritious white flesh and the embryo.

Brown Fiber Processing

The fibrous husks are soaked in pits or in nets in a slow moving body of water to swell and soften the fibres. The long bristle fibres are separated from the shorter mattress fibres underneath the skin of the nut, a process known as 'wet-milling'.

The mattress fibres are sifted to remove dirt and other rubbish, dried and packed into bales. Some mattress fiber is allowed to retain more moisture so that it retains its elasticity for 'twisted' fiber production. The coir fiber is elastic enough to twist without breaking and it holds a curl as though permanently waved. Twisting is done by simply making a rope of the hank of fiber and twisting it using a machine or by hand.

White Fiber Processing

To separate the white fibres, the immature husks are suspended in a river or water-filled pit for up to ten months. During this time micro-organisms break down the plant tissues surrounding the fibres to loosen them - a process known as retting. Segments of the husk are then beaten by hand to separate out the long fibres which are subsequently dried and cleaned. Cleaned fiber is ready for spinning into yarn in the home using a simple one-handed system or a spinning wheel. The final operation is grading before sale and shipping. 

 

Uses of Coir

Brown coir is used in brushes, doormats, mattresses and sacking. A small amount is also made into twine, used in this country as hop strings. Pads of curled brown coir fibre, made by 'needle-felting' (a machine technique that mats the fibres together) are shaped and cut to fill mattresses and for use in erosion control on river banks and hillsides. A major proportion of brown coir pads are sprayed with rubber latex which bonds the fibres together to be used as upholstery padding for the automobile industry in Europe. The material is also used for insulation and packaging.

The major use of white coir is in rope manufacture. Mats of woven coir fiber are made from the finer grades of bristle and white fiber using hand or mechanical looms.

Major Producers of Coir Fiber

Total world coir fiber production is 250,000 tonnes. The coir fiber industry is particularly important in some areas of the developing world. India, mainly the coastal region of Kerala State, produces 60% of the total world supply of white coir fiber. Sri Lanka produces 36% of the total world brown fiber output. Over 50% of the coir fiber produced annually throughout the world is consumed in the countries of origin, mainly India. Together India and Sri Lanka produce 90% of the 250,000 metric tons of coir produced every year.