Coats Industrial


Know About Textile Fibres

Bulletin Post 09

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Contents Cotton Plant Field

Fibre Classification
Natural Fibres
Man-made Fibres
Textile Fibre Parameters
Fibre Properties – Comparison

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Textiles have such an important bearing on our daily lives that everyone should know something about the basics of fibres and their properties.

Textile fibres are used for a wide range of applications such as covering, warmth, personal adornment and even to display personal wealth.

Textile technology has come a long way in meeting these requirements. A basic knowledge of textile fibres will facilitate an intelligent appraisal of fibre brands and types and help in identifying the right quality for the application.

This bulletin covers various textile fibres and the properties that are important for a suitable textile application.

Fibre Classification

Textile fibres can be broadly classified into two categories:

  • Natural fibres
  • Man-made fibres

Natural Fibres

Natural fibres are subdivided further, as outlined below, by their origin.

Fibre NameSourceComposition
CottonCotton bollCellulose
KapokKapok treeCellulose
LinenFlax stalkCellulose
JuteJute stalkCellulose
HempHemp or Abaca stalkCellulose
RamieRhea and China grassCellulose
SisalAgave leafCellulose
CoirCoconut huskCellulose
PinaPineapple leafCellulose
HairHair bearing animalsProtein
AsbestosVarieties of rockSilicate of Magnesium and Calcium

Man-made Fibres

Man-made fibres are subdivided as shown below with their various compositions and origin.

Fibre NameSource
RayonCotton linters or wood
AcetateCotton linters or wood
Tri-acetateCotton linters or wood
Non-Cellulosic Polymers
NylonAliphatic polyamide
AramidAromatic polyamid
PolyesterDihydric alcohol and terephthalic acid
OlefinEthylene or propylene
VinyonVinyl chloride
SaranVinylidene chloride
NovoloidPhenol based navolac
PolycarbonateCarbonic acid (polyester derivative)
AzlonCorn, soybean, etc.
RubberNatural or synthetic rubber
MetalAluminum, silver, gold, stainless steel
GlassSilica sand, limestone, other minerals
CeramicAluminium, silica

Hungary- cotton plant- IT1. Natural Fibres


Cotton, the natural fibre most widely used in apparel, grows in a boll around the seeds of cotton plants. A single fibre is an elongated cell that is a flat, twisted, hollow, ribbon-like structure.



  • Fair to good strength
  • Very little elasticity
  • Less resilient and prone to wrinkling
  • Comfortable and soft feel
  • Good absorbency
  • Conducts heat well
  • Damaged by insects, mildew, rot and moths
  • Weakened by extended sunlight exposure


  • Widely used in number of textile products
  • Commonly used in woven and knitted apparel
  • Home textile – bath towels, bath robes, bed covers etc.
  • Used as a blend with other fibres as rayon, polyester, spandex etc.

Cricket Ball with Linen ThreadLinen

Linen, one of the most expensive natural fibres, is made from the flax plant. It is labour-intensive to produce, hence produced in small quantities. However linen fabric is valued for its exceptional coolness and freshness in hot weather.

It is composed of 70% cellulose and 30% pectin, ash, woody tissue and moisture.



  • Strongest vegetable fibre
  • Poor elasticity, hence wrinkles easily
  • Relatively smooth, becomes softer when washed
  • Highly absorbent
  • Good conductor of heat and feels cool
  • Lustrous
  • More brittle, constant creasing in the sharp folds, tends to break
  • Damaged by mildew, perspiration and bleach
  • Resistant to moths and carpet beetles


  • Apparel - suits, dresses, skirts, shirts etc.
  • Home and commercial furnishing items – table cloths, dish towels, bed sheets, wallpaper / wall coverings, window treatments etc.
  • Industrial products - luggage, canvas etc.
  • Used as blend with cotton

Dyed New WoolWool

Wool fibre grows from the skin of sheep and is a relatively coarse and crimped fibre with scales on its surface. It is composed of protein. The fibre appearance varies depending on the breed of the sheep. Finer, softer and warmer fibres tend to be with more and smoother scales. Thicker, less warm fibres have fewer and rougher scales. Normally, the better wool fibres with finer scales are duller in appearance than the poorer quality fibres which have fewer scales.


  • Crimped in appearance
  • Elastic
  • Hygroscopic, readily absorbs moisture
  • Ignites at a higher temperature than cotton
  • Lower rate of flame spread, heat release and combustion heat
  • Resistant to static electricity


  • Clothing – jackets, suits, trousers, sweaters, hats etc.
  • Blankets, carpets, felt and upholstery
  • Horse rugs, saddle cloths

Silk PillowsSilk

Silk is a fine, continuous strand unwound from the cocoon of a moth caterpillar known as the silkworm. It is composed of protein. It is very shiny due to the triangular prism-like structure of the silk fibre, which allows silk cloth to refract incoming light at different angles.





  • Lustrous, smooth and soft texture and not slippery
  • Lightweight, strong, but can lose up to 20% of its strength when wet
  • Elasticity is moderate to poor. If elongated, it remains stretched
  • Can be weakened if exposed to too much sunlight
  • May be affected by insects, especially if left dirty
  • Can regain up to 11% of its moisture


  • Shirts, ties, blouses, formal dresses, high-fashion clothes
  • lingerie, pyjamas, robes, dress suits and sun dresses
  • Many furnishing applications
  • Upholstery, wall coverings, and wall hangings

Other Natural Fibres


Jute is taken from a tall plant of the same name and it is easy to cultivate and harvest. It is the cheapest fibre and is used in great quantities.


  • It is not durable as it deteriorates rapidly when exposed to moisture
  • Less strength
  • Cannot be bleached to make it pure white due to lack of strength


  • Binding threads for carpets, coarse and cheap fabrics, heavy bagging etc.


It is a white hair-like fibre obtained from the seed capsules of plants and trees called Ceiba Pentandra grown in Java and Sumatra (Indonesia), Mexico, Central America and the Caribbean, Northern South America and tropical West Africa.

It is called silk cotton due to its high lustre which is equal to that of silk.


  • Smooth texture
  • Very lustrous
  • Weak
  • Short fibre length
  • Resistant to moisture, dries quickly when wet


  • Mattresses, cushions, upholstered furniture


A woody fibre resembling flax and it is also known as rhea and China grass. It is taken from a tall flowering plant.


  • Stiff
  • More brittle
  • Lustrous


  • Canvas, upholstery, clothing, etc.

2. Man-made Fibres

2.1. Man-made (Regenerated)


They are derived either from the cellulose of the cell walls of short cotton fibres that are called linters or, more frequently from pine wood. There are three types of man made cellulosic fibres:

Rayon, acetate and tri-acetate.

Viscose Rayon and Alcazar ThreadRayon

Rayon is made from naturally occurring polymers that simulate natural cellulosic fibres. It is neither a truly synthetic fibre nor a truly natural fibre.

There are two varieties of Rayon; viscose and high wet modulus (HWM). These in turn are produced in a number of types to provide certain specific properties.





  • Soft, smooth and comfortable
  • Naturally high in lustre
  • Highly absorbent
  • Durability and shape retention is low, especially when wet
  • Low elastic recovery
  • Normally weak, but HWM rayon is much stronger, durable and has good appearance retention.


  • Apparel - blouses, dresses, jackets, lingerie, linings, suits, neck ties etc.
  • Furnishing items - bedspreads, bed sheets, blankets, window treatments, upholstery etc.
  • Industrial uses e.g. medical surgery products, non-woven products, tyre cord etc.
  • Other uses - feminine hygiene products, diapers, towels etc.


Acetate consists of a cellulose compound identified as acetylated cellulose – a cellulose salt. Hence it possesses different qualities compared to rayon.

Acetate is thermoplastic and can be formed into any shape by application of pressure combined with heat. Acetate fibres have good shape retention.


  • Thermoplastic
  • Good drapability
  • Soft, smooth and resilient
  • Wicks and dries quickly
  • Lustrous appearance
  • Weak, rapidly loses strength when wet, must be dry-cleaned
  • Poor abrasion resistance


  • Primarily in apparel - blouses, dresses, jackets, lingerie, linings, suits, neck ties, etc.
  • Used in fabrics such as satins, brocades, taffetas, etc.


Tri-acetate consists of acetylated cellulose that retains acetic groupings, when it is being produced as triacetate cellulose. It is a thermoplastic fibre and is more resilient than other cellulosic fibres


  • Thermoplastic
  • Resilient
  • Shape retentive and wrinkle resistant
  • Shrink resistant
  • Easily washable, even at higher temperatures
  • Maintains creases and pleats well


  • Primarily apparel
  • Used in clothing where crease / pleat retention is important e.g. skirts and dresses
  • Can be used with polyester to create shiny apparel

2.2. Man-made – Non-cellulosic 

Polymer Fibres

This group of fibres is distinguished by being synthesised or created from various elements into larger molecules that are called linear polymers.

The molecules of each particular compound are arranged in parallel lines in the fibre. This arrangement of molecules is called molecular orientation.

The properties of such fibres are dependent on their chemical composition and kinds of molecular orientation.


In nylon, the fibre forming substance is a long-chain synthetic polyamide in which less than 85% of the amide linkages are attached directly to two aromatic rings. The elements carbon, oxygen, nitrogen and hydrogen are combined by chemical processes into compounds which react to form long-chain molecules, chemically known as polyamides and are then formed into fibres. There are several forms of nylon. Each depends upon the chemical synthesis.

They are: Nylon 4; 6; 6.6; 6.10; 6.12; 8; 10; and 11.


  • Highly resilient
  • High elongation and elasticity
  • Very strong and durable
  • Excellent abrasion resistance
  • Thermoplastic
  • Has the ability to be very lustrous, semi-lustrous or dull
  • Resistant to insects, fungi, mildew and rot


  • Apparel – pantyhose, stockings, leggings, etc.
  • Home furnishing
  • Industrial applications - parachutes, tyre cords, ropes, airbags, hoses, etc.


In polyester, the fibre forming substance is any long-chain synthetic polymer composed of at least 85% by weight of an ester of a substituted aromatic carboxylic acid, but not restricted to substituted terapthalate units and para-substituted hydroxybenzoate units.

In producing such fibres, the basic elements of carbon, oxygen and hydrogen are polymerised. Variations are possible in the methods of production, in the combination of ingredients and in the ultimate molecular structures of the fibre forming substance.


  • Thermoplastic
  • Good strength
  • Hydrophobic (non absorbent)


  • Apparel – woven and knits, shirts, pants, jackets, hats etc.
  • Home furnishing – bed sheets, blankets, upholstered furniture, cushioning material
  • Industrial uses – conveyor belts, safety belts, tyre reinforcement


The fibre forming substance used to produce spandex is any long-chain synthetic polymer composed of at least 85% of segmented polyurethane. Variations are possible when producing this fibre.

The basic elements of nitrogen, hydrogen, carbon and oxygen are synthesised with other substances to ethyl ester compounds in polymer chains of soft segments or sections that provide stretch and harder segments that hold the chain together.

Trademarks of three spandex fibres are Cleer-span, Glospan and Lycra.


  • Highly elastic
  • Comfortable
  • High shape retention
  • Durable


  • Never used alone, but always blended with other fibres
  • Apparel and clothing items with stretch for comfort and fit
  • Hosiery
  • Foundation garments
  • Swimwear, athletic, aerobic apparel
  • Lingerie, leggings and socks
  • Shaped garments e.g. bra cups
  • Gloves

Sofa Acrylic TextileAcrylic

In acrylics, the fibre forming substance is any long chain polymer composed of at least 85% by weight of acrylonitrile units. Using complicated processes, carbon, hydrogen and nitrogen, the basic elements are synthesised with small amounts of other chemicals into larger polymer combinations. Variations are possible in the methods of production, in the combination of ingredients and in the ultimate molecular structures of the fibre forming substance.



  • Soft, warm handling characteristics similar to wool
  • Resilient
  • Shape retentive


  • Apparel
  • Home furnishing

3. Man-made – Protein Fibres

The protein from such products as corn and milk has been processed chemically and converted into fibre. However, such fibres are not commercially successful.

4. Man-made – Rubber Fibres

The fibre forming substance is comprised of natural and synthetic rubber. The treated rubber is produced in strands, so that the cross-section is either round or square and the longitudinal surface is relatively smooth.

Metallic thread on jeans5. Man-made – Metallic Fibres

These fibres are composed of metal, plastic-coated metal, metal-coated plastic, or a core completely covered by metal. These fibres are usually produced in flat, narrow, smooth strips which possess high lustre.



  • Decorative yarns in apparel and home furnishing items.

6. Man-made – Mineral Fibres

Various minerals have been manufactured into glass, ceramic and graphite fibres having prescribed properties for specific uses.


Although glass is a hard and inflexible material, it can be made into a fine, translucent textile fibre that has an appearance and feel of silk.

Natural minerals such as silica sand, limestone, soda ash, borax, boric acid, feldspar and fluorspar have been fused under very high temperatures into glass which is processed into a fibre.


  • Inert
  • Highly flame resistant


  • Heat resistant industrial applications

Textile Fibre Parameters

Fibrous materials should possess certain properties to become a suitable textile raw material. Properties which are essential for acceptance as a suitable raw material may be classified as ‘primary properties’. The other properties which add specific desirable character or aesthetics to the end product and its use may be classified as ‘secondary properties’.

Primary Properties

  1. Length
  2. Tenacity (strength)
  3. Flexibility
  4. Cohesion
  5. Uniformity of properties

Secondary Properties

  1. Physical shape
  2. Specific gravity (influence weight, cover etc.)
  3. Moisture regain and absorption (comfort, static electricity etc.)
  4. Elastic character
  5. Thermo plasticity (softening point and heat - set character)
  6. Dyeability
  7. Resistance to solvents, corrosive chemicals, micro-organisms and environmental conditions
  8. Flammability
  9. Lustre

Physical Properties


Microscopic appearanceFlat, twisted and ribbon-like
LengthStaple fibre, length ranges from 1 to 5.5 cm
ColourCreamy white in natural form, unless treated
LustreMedium, unless treated for lustre
Moisture absorptionExcellent
HeatWill withstand moderate heat / Decomposes after prolonged exposure to temperatures of 150°C / 320°F or over
FlammabilityBurns readily


Microscopic appearanceCross-section is made up of irregular polygonal shapes
LengthLong staple, 25 to 120 cms
ColourOff white
Moisture absorptionGood
HeatWill withstand moderate heat
FlammabilityScorches and flames readily


Microscopic appearanceCrimped
LengthStaple fibre, up to 40 cms
ColourGenerally creamy white, some breeds of sheep produce natural colours such as black, brown, silver, and random mixes.
Moisture absorptionTends to repel initially, but good absorption.
HeatBecomes harsh at 100°C / 212°F, decomposes at slightly higher temperatures.
FlammabilityScorches at 204°C / 400°F, will char


Microscopic appearanceTriangular prism-like structure
LengthContinuous filament
ColourUsually off white, and also shades of pale beige, brown, and grey
Moisture absorptionGood
HeatSensitive and gets decomposed
FlammabilityBurns at 165°C / 330°F


Microscopic appearance

Striations seen in viscose and high strength rayon

If delustred, scattered specks of pigment can be seen

LengthFilament and Staple
ColourTransparent unless dyed

Fair to excellent
Regular rayon has fair strength
High tenacity types have good strength


Regular rayon: low
High strength rayon: good

ResilenceHigh wet strength rayon is better
Moisture absorption

Higher than natural cellulose
Fibres swell in water
Weaker when wet


Loses strength above 148°C / 300°F
Decomposes between 176°C / 350°F and 204°C / 400°F

FlammabilityBurns rapidly unless treated
Electrical conductivityFair – static charge can be reduced with special finishes


Microscopic appearance

Striations farther apart than viscose rayon
Lobed cross-section

LengthFilament and staple
ColourTransparent unless dulled by pigments
LustreBright, semi bright or dull
StrengthModerate, less than rayon when it is wet
ElasticityNot very high, similar to rayon
Moisture absorption6%, little strength loss when it is wet
HeatIroning temperatures of 135°C / 275°F are satisfactory
FlammabilitySlowly combustible
Electrical conductivityGood


Microscopic appearanceVery smooth and even
LengthFilament and staple
ColourOff white
LustreHigh natural lustre that can be controlled
StrengthExceptionally high
ElasticityExceptionally high
ResilienceVery good
Moisture absorption3.8%
HeatHigh resistance, melts at 250°C / 482°F
FlammabilityMelts slowly Does not support combustion
Electrical conductivityLow, generates static


Microscopic appearanceSmooth, even, rod like, different cross sectional shapes
LengthFilament and staple
LustreBright or dull
StrengthGood to excellent
ElasticityFair to good
Moisture absorptionLess than 1%
HeatSoftening or sticking temperature is above 204°C / 400°F
FlammabilityBurns slowly
Electrical conductivityAccumulates static charges


Microscopic appearanceUniform and smooth surface Irregular spaced striations
LengthMainly a staple fibre
LustreBright or dull
StrengthFair to good strength
Moisture absorption1 - 3%

Yellowing may occur above 148°C / 300°F
Softening or stocking about 232°C / 450°F

FlammabilityBurns with yellow flame
Electrical conductivityFair to good

Fibre Properties - Comparison


FibreMoisture regain*
Cotton7 -11
Wool13 - 18
Acrylic1.3 - 2.5
Glass0 - 0.3
Nylon4.0 - 4.5
Polyester0.4 - 0.8
Rayon HWM11.5 - 13
Spandex0.75 - 1.3

*Moisture regain is expressed as a percentage of the moisture-free weight at 70º Fahrenheit and 65% relative humidity.

Thermal properties

FibreMelting PointSoftening Sticking PointSafe Ironing Temperature
CottonNon melting425218
FlaxNon melting450232
SilkNon melting300149
WoolNon melting300149
Acrylic400 - 490204 - 254300 - 350149 - 176
AramidDoes not melt, carbonises above 426°C / 800°F
Glass1400 - 3033
Nylon 6414212340171300149
Nylon 66482250445229350177
Polyester PET480249460238325163
Polyester PCDT550311490254350177
RayonNon melting375191

Effects of Acids

CottonDisintegrates in hot dilute and cold concentrated mineral acids
LinenDisintegrates in hot dilute and cold concentrated acids
WoolDestroyed by hot sulphuric, otherwise unaffected by acids
SilkOrganic acids do not harm, concentrated mineral acids will dissolve
RayonDisintegrates in hot dilute and cold concentrated acids
AcetateSoluble in acetic acid, decomposed by strong acids
Tri-acetateSoluble in acetic acid, decomposed by strong acids
NylonDecomposed by strong mineral acids, resistant to weak acids
PolyesterResistant to most mineral acids; disintegrated by 96% sulphuric acid
SpandexResistant to most mineral acids, some discolouration can happen
AcrylicResistant to most acids
GlassResistant to most acids

Effects of Alkalis

CottonNot harmed by alkalis
LinenHighly resistant
WoolAttacked by weak alkalis, destroyed by strong alkalis
SilkDamaged only under high temperature and concentration
RayonDisintegrates in concentrated solutions
AcetateNot affected, unless high concentration and temperature is applied
Tr-acetateNot affected, unless high concentration and temperature is applied
NylonLittle or no effect
PolyesterResistant to cold alkalis, slowly decomposed at a boil by strong alkalis
AcrylicDestroyed by strong alkalis at boil, resists weak alkalis
GlassAttacked by hot weak alkalis and concentrated alkalis

Effects of Organic Solvents

CottonOxidises, turning yellow and losing strength on long exposure
LinenResistant than cotton, gradually deteriorate from prolonged exposure
WoolStrength loss due to prolonged exposure
SilkContinuous exposure weakens
RayonGenerally resistant, loses strength after long exposure
AcetateApproximately same as rayon
Tri-acetateResistant, loses strength after long exposure
NylonGood resistance
PolyesterGood resistance
SpandexGenerally not affected, prolonged exposure weakens
AcrylicLittle or no effect

Effects of Sunlight

CottonOxidises, turning yellow and losing strength on long exposure
LinenResistant than cotton, gradually deteriorate from prolonged exposure
WoolStrength loss due to prolonged exposure
SilkContinuous exposure weakens
RayonGenerally resistant, loses strength after long exposure
AcetateApproximately same as rayon
Tri-acetateResistant, loses strength after long exposure
NylonGood resistance
PolyesterGood resistance
SpandexGenerally not affected, prolonged exposure weakens
AcrylicLittle or no effect

Cleanliness and Washability

FibreBehaviour and effect
CottonLaunders well and gives up dirt easily
LinenLaunders well and gives up dirt easily
WoolAttracts dirt, unless thoroughly cleaned it retains odors
SilkPrevents dirt from settling. Smooth surface allows stains to be easily washed away
RayonPrevents dirt from settling. Smooth surface allows stains to be easily washed away
AcetatePrevents dirt from settling. Smooth surface allows stains to be easily washed away
Tri-acetatePrevents dirt from settling. Smooth surface allows stains to be easily washed away
Nylon 6.6Prevents dirt from settling. Smooth surface allows stains to be easily washed away
PolyesterPrevents dirt from settling. Smooth surface allows stains to be easily washed away
SpandexLaunders well
AcrylicLaunders well

Effects of Perspiration

CottonResistant to alkali perspiration, slight deteriorating effect with acid perspiration
LinenResistant to alkali perspiration, slight deteriorating effect with acid perspiration

Weakened by alkali perspiration 

Discolouration happens in general with perspiration

SilkDeteriorates and Colour is affected causing stains
RayonFairly resistant to deterioration
AcetateGood resistance
Tri-acetateGood resistance
Nylon 6.6Resistant, Colour may be affected
SpandexGood resistance to degradation
AcrylicNo deterioration

*Perspiration can be acidic or alkaline, depending on the individual's metabolism.

Effects of Mildew

FibreBehaviour and effect
CottonAffected in a damp condition
LinenAffected in a damp condition
WoolNot susceptible in ordinary condition, but in damp condition
SilkNot susceptible in ordinary condition, but in damp condition
RayonAffected in a damp condition
AcetateHighly resistant
Tri-acetateExtremely high resistance
NylonNo effect
PolyesterAbsolutely resistant
SpandexGood to excellent resistance

May form, but will have no effect

Can be easily wiped off

Effect of Heat

FibreBehaviour and effect

Withstand moderate heat

Will scorch and burn with prolonged exposure to high heat


Withstand moderate heat 

Will scorch and burn with prolonged exposure to high heat

WoolNot easily combustible, becomes harsh at 100°C / 212°F and will scorch at 204°C / 400°F and eventually char
SilkSensitive to heat, decomposes at 165°C / 330°F
RayonBehaves similar to cotton as a cellulosic fibre
AcetateThermoplastic in nature, gets sticky at 176°C / 350°F and becomes stiff later
Tri-acetateThermoplastic in nature, gets sticky at 298°C / 570°F and becomes stiff later
NylonWill melt under high temperature, Nylon 6 melts at 215°C / 420°F and Nylon 6, 6 248°C / 480°F

Will melt under high temperature 

Becomes sticky at 226°C / 440°F to 243°C / 470°F and melts and flames at 248°C / 480°F to 290°C / 554°F depending on its type

SpandexYellows and loses elasticity and strength at over 148°C / 300°F, sticks at 175°C / 347°F and melts at 230°C / 446°F
AcrylicBecomes sticky at 229°C / 455°F and melts at higher temperature

Effects of Insects

FibreBehaviour and effect
CottonNot damaged
LinenNot damaged
WoolVulnerable to moths and carpet beetles
SilkMay be attacked by larvae of cloth moths or carpet beetles
RayonNot attracted
AcetateNot attracted
Tri-acetateNot attracted