2. FIBERS
Fiber:
It is defined as one of the delicate, hair portions of the
tissues of a plant or animal or other substances that are very
small in diameter in relation to there length. A fiber is a material
which is several hundred times as long as its thick.
Textile Fiber:
Textile fiber has some characteristics which differ between
fiber to Textile fiber. Textile fiber can be spun into a yarn or made into
a fabric by various methods including weaving, knitting, braiding,
felting, and twisting. The essential requirements for fibers to be spun
into yarn include a length of at least 5 millimeters, flexibility,
cohesiveness, and sufficient strength. Other important properties
include elasticity, fineness, uniformity, durability, and luster.
3. • Types of Textile Fiber:
• Generally two types of fiber.
• 1. Natural fiber.
• 2. Manmade fiber.
• Natural Fiber:
• Natural fibers include those produced by plants, animals, and geological processes. They are
biodegradable over time. They can be classified according to their origin.
•
• A class name for various genera of fibers (including filaments) of:
• (1) animal (i.e., silk fiber and wool fiber);
• (2) mineral (i.e., asbestos fiber); or
• (3) vegetable origin (i.e., cotton fiber, flax fiber, jute fiber, and ramie fiber).
• Manmade Fiber:
• Synthetic or man-made fibers generally come from synthetic materials such as
petrochemicals. But some types of synthetic fibers are manufactured from natural cellulose;
including rayon, modal, and the more recently developed Lyocell. A class name for various
genera of fibers (including filaments) produced from fiber-forming substances which may be:
•
• (1) Polymers synthesized from chemical compounds, e.g., acrylic fiber, nylon fiber, polyester
fiber, polyethylene fiber, polyurethane fiber, and polyvinyl fibers;
•
• (2) Minerals, e.g., glasses. The term manufactured usually refers to all chemically produced
fibers to distinguish them from the truly natural fibers such as cotton, wool, silk, flax, etc.e.g:
Glass fiber,
4. PROPERTIES OF FIBERS
A) Physical Properties
1. Length
2. Fineness
3. Crimp
4. Maturity
5. Lusture
6. Softness
7. Resiliency
8. Work of rupture
9. Density
10. Appearance
11. Flexibility
12. Toughness
13. Elorgation
B)Mechanical Properties
1. Strength
2. Elasticity
3. Extensibility
4. Rigidity
6. PROPERTIES:
1. Upper Half Mean Length (in inches)
A. #1 Upland Virgin Staple 0.70 - 1.30
B. Gin Motes 0.50 - 0.80
C. Comber <0.50
D. First Cut linters 0.25- 0.50
2. Fiber Diameter
A. Micronaire 2.0 - 7.0
B. Approximate Denier 0.7 - 2.5
7. 3. Elastic Recovery (by percent)
A. At 2 % Extension 74
%
B. At 5% Extension 45
%
4. Breaking Elongation (dry) 3-
9.5
5. Tensile Strength (g per tex/g
per denier)
A. Dry 27
-
44
/
3.0
-
4.9
B. Wet 28
-
57
/
3.3
-
6.4
8. 6. Moisture Regain at Standard Conditions 7%
7. Water Absorbing Capacity (USP method) >24
grams of water per gram of fiber
8. Density (g/cm3) 1.54
9. Degree of Polymerization9,000 - 15,000
10. Crystallinity by X-ray Diffraction (average)
73%
11. Color (Whiteness Index)90 - 100
9. 12. Thermal Resistance
A. Long exposure to dry heat above 300
0
F will cause gradual decomposition
B. Temperatures greater than 475
0
F cause rapid deterioration
13. Acid Resistance
A. Disintegrated by hot dilute acids or cold concentrated acids
B. Unaffected by cold weak acids
14. Alkali Resistance
A. Swelling in NaOH above 15% concentration but no damage
15. Organic Solvent Resistance
A. Resistant to most common industrial and household solvents
12. PROPERTIES:
Tensile Strength: Linen is a strong fiber. It has a
tenacity of 5.5 to 6.5 gm/den. The strength is
greater than cotton fiber.
Elongation at break: Linen does not stress easily. It
has an elongation at break of 2.7 to 3.5 %.
Color: The color of linen fiber is yellowish to grey.
Length: 18 to 30 inch in length.
Lusture: It is brighter than cotton fiber and it is
slightly silky.
Elastic Recovery: Linen fiber has not enough elastic
recovery properties like cotton fiber
13. Moisture Regain (MR %): Standard moisture
regain is 10 to 12%.
Resiliency: Very poor.
Effect of Heat: Linen has an excellent resistance
to degradation by heat. It is less affected than
cotton fiber by the heat.
Effect of Sun Light: Linen fiber is not affected by
the sun light as others fiber. It has enough ability
to protect sun light.
14. Effect of Acids: Linen fiber is damaged by highly
densified acids but low dense acids does not
affect if it is wash instantly after application of
acids.
Effects of Alkalis: Linen has an excellent
resistance to alkalis. It does not affected by the
strong alkalis.
Effects of Bleaching Agents: Cool chlorine and
hypo-chlorine bleaching agent does not affect
the linen fiber properties.
Effect of Organic Solvent: Linen fiber has high
resistance to normal cleaning solvents.
15. Effect of Micro Organism: Linen fiber is attacked
by fungi and bacteria. Mildews will feed on linen
fabric, rotting and weakling the materials.
Mildews and bacteria will flourish on linen
under hot and humid condition. They can be
protected by impregnation with certain types of
chemicals. Copper Nepthenate is one of the
chemical.
Effects of Insects: Linen fiber does not attacked
by moth-grubs or beetles.
Dyes: It is not suitable to dye. But it can be dye
by direct and vat dyes.
19. • End use
• Jute is used for making yarn, twine, rope,
sacking, cloth, hessian cloth, carpet
backing cloth, carpet, mat, wall cloth,
shopping bag, and as packing materials.
21. PROPERTIES:
Composition: The silk fibre is chiefly composed of 80% of fibroin, which is
protein in nature and 20% of sericin, which is otherwise called as silk gum.
Strength: Silk as a fibre, has good tensile strength, which allows it to
withstand great pulling pressure. Silk is the strongest natural fibre and has
moderate abrasion resistance. The strength of the thrown yarns is mainly due
to the continuous length of the fibre. Spun silk yarn though strong is weaker
than thrown silk filament yarns.
Elasticity: Silk fibre is an elastic fibre and may be stretched from 1/7 to 1/5 of
its original length before breaking. It tends to return to its original size but
gradually loses little of its elasticity. This would mean that the fabric would be
less sagging and less binding resulting in the wearers comfort.
Resilience: Silk fabrics retain their shape and have moderate resistance to
wrinkling. Fabrics that are made from short – staple spun silk have less
resilience.
22. Drapability: Silk has a liability and suppleness that, aided
by its elasticity and resilience, gives it excellent
drapability.
Heat Conductivity: Silk is a protein fibre and is a non-
conductor of heat similar to that of wool. This makes silk
suitable for winter apparel.
Absorbency: Silk fabrics being protein in nature have
good absorbency. The absorptive capacity of the silk
fabric makes comfortable apparel even for warmer
atmosphere. Fabrics made from silk are comfortable in
the summer and warm in the winter. Silk fibre can
generally absorb about 11 percent of its weight in
moisture, but the range varies from 10 percent to as
much as 30 percent. This property is also a major factor in
silk’s ability to be printed and dyed easily.
23. Cleanliness and Washability: Silk fabric does not attract dirt
because of its smooth surface. The dirt, which gathers can be
easily removed by washing or dry cleaning. It is often
recommended for the silk garments to be dry-cleaned. Silk
fabrics should always be washed with a mild soap and strong
agitation in washing machine should be avoided. Silk water –
spot easily, but subsequent washing or dry cleaning will
restore the appearance of the fabric.
Reaction to Bleaches: Silk, like wool, is deteriorated with
chlorine bleaches like sodium hypochlorite. However, mild
bleach of hydrogen peroxide or sodium per borate may be
used for silk.
Shrinkage: Silk fabrics are subjected only to normal shrinkage
which can be restored by ironing. Crepe effect fabrics shrink
considerably in washing, but careful ironing with a moderately
hot iron will restore the fabric to its original size.
24. Effect of Heat: Silk is sensitive to heat and begins to decompose at 330° F
(165° C). The silk fabrics thus have to be ironed when damp.
Effect of Light: Silk fabric weakens on exposure to sun light. Raw silks are
more resistant to light than degummed silk.
Resistance to Mildew: Silks will not mildew unless left for sometime in a
damp state or under the extreme conditions of tropical dampness.
Resistance to Insects: Silk may be attacked by the larvae or clothe moths or
carpet beetles.
Reaction to Alkalis: Silk is not as sensitive as wool to alkalis, but it can be
damaged if the concentration and the temperature are high. A mild soap or
detergent in lukewarm water is thus advisable.
Reaction to Acids: Concentrated mineral acids will dissolve silk faster than
wool. Organic acids do not harm silk.
Affinity for Dyes: Silk has good absorbency and thus has good affinity for dyes.
Dyed silk is colourfast under most conditions, but its resistance to light is
unsatisfactory.
Resistance to Perspiration: Perspiration and sunlight weakens and yellows silk
fabrics. The silk itself deteriorates and the colour is affected causing staining.
Garments worn next to the skin should be washed or other wise cleaned after
each wearing.
25. USES:
Silk fiber is widely used to make different items.
In apparel industry Silk is used for making
Dresses, Blouses, Skirts, Jackets, Pants, Scarves
and ties.
30. PROPERTIES:
Moisture Absorption
It absorbs more moisture than cotton. Moisture Content of Coton is
6% at 70 deg F and 65% RH, and for Viscose Rayon it is 13% under the
same conditions.
Tensile Strength
The Tensile Strength of the fibre is less when the fibre is wet than
when dry. It is 1.5-2.4 gpd in the dry state and 0.7-1.2 gpd in the wet
state. For high tenacity variety the values are 3-4.6 gpd and 1.9 to 3.0
gpd.
Elasticity
The elasticity of Viscose Rayon is less than 2-3%. This is very important
in handling viscose yarns during weaving, stentering etc when sudden
tensions are applied.
31. Elongation at Break
Ordinary Viscose rayon has 15-30% elongation at break,
whule high tenacity rayon has only 9-17% elongation at
break.
Density
The density of Viscose rayon is 1.53 g/cc. Rayon filaments
are available in three densities: 1.5, 3.0 and 4.5
Action of Heat and Light
At 300 deg F or more, VR loses its strength and begins to
decompose at 350-400 deg F. Prolonged exposure to
sunlight also weakens the fibre due to moisture and
ultraviolet light of the sunlight.
32. Action of Acids:
The resistance of regenerated cellulose rayon’s to acids is
generally less than that of cotton to the same concentrations
of the same acids. Therefore , acid treatments must not be
too drastic with respect to concentration ,temperature and
time .Organic acids can be safely used in 1 to 2 percent
concentration without injury to the fiber. Inorganic acids such
as hydrochloric & nitric can be used in surprisingly strong
concentrations provided the temperatures are not too high
and the treatment is brief. Oxalic acid for removal of iron
stains is not recommended except at temperatures lower than
150°F.At high temperatures and concentrations all acid will
destroy or carbonize regenerated rayon’s. No harmful action
will result if applied at .5 to 3 percent solution at room
temperature.
33. Action of Solvents
Textile solvents can be used on Viscose rayon without any
deteriorating effect. Viscose rayon dissolves in
cuprammonium hydroxide solution.
Effect of Iron
Contact with iron in the form of ferrous hydroxide
weakens viscose rayon yarns. Therefore staining, marking
or touching of rayon to iron or iron surface should be
avoided.
Action of Microorganisms
Microorganisms ( moulds, mildew, fungus, bacteria) affect
the colour, strength, dyeing properties and lustre of
rayon. Clean and dry viscose rayon is rarely attacked by
moulds and mildew.
34. USES:
• ayon typically has an elevated luster quality giving it a
brilliant gloss
• Mainly, Rayon fibres are used in apparel industry such
as Aloha shirts, blouses, dresses, Jackets, Lingerie,
scarves, suits, ties, hats and socks…,
• Some rayon fibres are for filling in Zippo lighters,
furnishings including bedspreads, bedsheets, blankets,
window covers, upholstery and slipcovers..,
• For industrial purposes such as medical surgery
products, non-woven items, tire cord and some other
uses like diapers, towels, feminine hygiene products..,
36. PROPERTIES:
• Length
• The length of the acrylic fibre can be controlled. That means, it may be in filament or staple
form.
• Fineness
• Fineness of this fibre is also controllable. The filament yarns are made 75 to 200 denier
ranges while staple fibres are made 2 and 3 denier cut into 1.5”, 2”, 3” and 4” length.
• Strength and Extension
• It is fairly strong fibre. Its tenacity is 5 gm per denier in dry state and 4.8 gm per denier in wet
state. Extension at break is 15%. Good recovery from deformation.
• Elasticity
• It has an elastic recovery of 85% after 4% extension when the load is extremely released.
• - See more at: http://textileapex.blogspot.com/2015/03/properties-of-acrylic-
fibre.html#sthash.KpQfZWf9.dpuf
37. • Cross-sectional shape
• Normally round but cross-section of this fibre could be varied.
•
• Appearance
• It is about 30% bulkier than wool. Regarding insulating warmth, it has
about 20% greater insulating power than wool.
•
• Effects of chemical
• Acid: It has good resistance to mineral acid.
• Alkali: The resistance to weak alkali is fairly good but hot strong alkali
damages this fibre.
• Solvent: It has excellent resistance to common solvents, oils, greases, and
natural salts.
• Water: moisture regain of this fibre varies from 1.5% to 3%. Easy to wash
and quick drying.
• - See more at: http://textileapex.blogspot.com/2015/03/properties-of-
acrylic-fibre.html#sthash.KpQfZWf9.dpuf
38. • Effect of heat and sunlight
• This fiber has very good thermal stability. Safe ironing temperature
is at 1600C. At 230 – 2350C acrylic sticks with the iron i.e. melting
occurs. High temperature may sometime causes yellowing of this
fibre.
•
• Effect of Biological agents
• This fibre is unaffected by mildew, moulds, larves and insects.
•
• End use
• 100% acrylic is used mainly in sweater, jersey, knit outer wear fabric
and blankets. It is used as a blend component with cotton,
viscose, wool etc. It has good warmth and recovery property. It is
also used for making carpet due to good resiliency property.
• - See more at: http://textileapex.blogspot.com/2015/03/properties-
of-acrylic-fibre.html#sthash.KpQfZWf9.dpuf
40. PROPERTIES:
• Tenacity: Polyester filaments and staple fibre are
strong due to their crystalline nature. The crystalline
nature permits for the formation of highly effective
Vander wall’s forces as well as since hydrogen bonds
which provided the fibre its good tenacity. The tenacity
remains unchanged when wet since the fibre resists
the entry of water molecules to a significant extent.
• Elastic plastic nature: The very crystallinity of the fibre
prevents wrinkling and creasing. Repeated stretching
and straining causes, distortion of the polymer system
as the Vander wall’s forces cannot withstand much
stretching.
41. Thermal properties: It is a poor heat conductor
and it has low resistance to heat. It melts on
heating. Polyester textile materials can be
permanently heat-set. It is a thermoplastic fibre
meaning that it is capable of being shaped or
turned when heated. Thermoplastic fibres
heated under strictly controlled temperatures
soften and can then be made to similar to a flat,
creased or pleated configuration. When cooled
thermoplastic fibres retain the new
configuration.
42. • Effect of acids: These polymers are resistant to acids.
• Effetc of alkalis: Alkaline conditions as seen in laundering
hydrolyse the ester groups in polyester polymers. The
crystalline nature prohibits hydrolysis to a greater extent
and it is the surface of filament which gets hydrolysed.
Continued laundering results in hydrolysis and materials get
fewer as the surface film of the fibre gets lost.
• Effect of bleaches: It does nor requie bleaching. It retains
its whiteness and requires only chlorine bleaches to be
used when essential.
• Sunlight: It withstands the sun’s ultra-violate radiations and
is resistant to acidic pollutants in atmosphere.
• Color Fastness: It is not easy for dye molecule to penetrate
the fibre when dyed, it retains its color after regular wash.
• Micro-Organisms: It is resistant to bacteria and other mcro-
organisms.
43. USES:
Polyester is used in the manufacturing of all
kinds of clothes and home furnishings like
bedspreads, sheets, pillows, furniture, carpets
and even curtains. The disco clothing of the 70s
with all its jazz and flash was made of polyester.
