2. Southeast University
Department Of Textile Engineering
I/A 251,252 Tejgaon Dhaka Bangladesh
Prepared by : Mazadul Hasan sheshir

3. Welcome
to
our presentation

4. •
•
•
•
•
•
•
•
•
•
•
•
Textile & Textile fiber
Man-made fiber & it’s classification
Definition of different types of man made fiber
Flow chart of synthetic process of man made fiber.
Properties of man made fiber.
Influence of chemical structure on man made fiber.
Spinning process & it’s general principle.
Different types of spinning process with figure.
Viscose & it’s manufacturing process
Note on cuprammonium rayon .
Lyocell & its process flowchart.
Notes on cotton count ,Denier, tex , millitex & their conversion.

5. Textile, Textile Fiber & it’s classification
Textile : A textile is a flexible material consisting of a network of natural or artificial
fibers oftenreferred to as thread or yarn.
Textile Fiber: Textile fibers are defined as unit of matters characterized by flexibility,
fineness, and high ratio of length to thickness.
Classification of Textile Fibers:
• Naturally occurring fibers of vegetable origin.
• Naturally occurring fibers of animal origin.
• Regenerated man-made fibers which use some naturally occurring substance as the
raw material.
• Synthetic man-made fibers which use synthetic organic compounds as the raw
material.
• Mineral fibers which are entirely inorganic.

6. Denier
The denier of a yarn is the wt. in gms of a length of 9000m of
that yarn.
• The coarseness of a yarn or a filament is usually gauged as denier.
• Denier is a unit of measure for the linear mass density of fibers.
• If 9000 meters of yarn weigh 100 grams - the yarn is said to be 100
denier.
• The term micro-denier is used to describe filaments that weigh less
than one gram per 9,000 meter length.

7. Denier
• Filament Denier only relates to a single filament.
• Total Denier relates to a yarn, an agglomeration of filaments.
• D.P.F. =
Total Denier
Quantity of Uniform Filaments
(D.P.F is commonly known as Denier per Filament)
• If a yarn of 100 denier is composed of either 20 or 60 filaments,
then the filament denier will be:
• For 20 filaments yarn, D.P.F. =100/20 =5 denier -coarse filament
• For 60 filaments yarn, D.P.F. =100/60 =1.7 denier -fine filament

8. Cotton Count, Tex & millitex
The yarn numbering system based on length and weight originally used for
cotton yarns and now employed for most staple yarns spun on the cotton or
short-staple, system.
• It is based on a unit length of 840 yards, and the count of the yarn is equal
to the number of 840-yard skeins required to weigh 1 pound.
• Under this system, the higher the number, the finer is the yarn.
Tex is a unit of measure for the linear mass density of fibers and is
defined as the mass in grams per 1000 meters.
The most commonly used unit is actually the decitex
abbreviated dtex, which is the mass in grams per 10,000 meters.
When measuring objects that consist of multiple fibers the term
"filament tex" is sometimes used, referring to the mass in grams per
10,000 meters of a single filament.

9. Conversion factor for 1s cotton counts
• 840 yds. of cotton weighs
=1 lb
• 840 m "
"
weighs
=453.6 X 1.093613298 gm
• 9000 m "
"
weighs =453.6 X 1.093613298 X 9000/840 gm
• = 5315 gm or 5315
(equivalent denier or conversion factor)
Therefore, for 25s, Denier (D) = 5315 / 25, that is, D = 5315 / C
• 50s cotton count
• 2/50s cotton count
• 106.3 denier
= 5315/50 = 106.3 denier
= 5315/25
= 212.6 denier
= 5315/106.3 = 50s cotton count

10. From the linear mass density of fibers
9 denier ≈ 1.0000 tex
1 denier ≈ 0.1111 tex
So any number of D (Denier) ≠ any number of T (Tex)
From above
or
or
or
T = D X 0.1111
T = (5315 / C ) 0.1111
(as we know D = 5315 / C)
T = 590.5 / C
TC = 590.5 = 591

11. Man-made fiber & it’s classification
Man-made Fiber : A class name for various fibers (including filaments)
synthetically produced from fiber-forming substances which usually refer
to all chemically produced fibers to distinguish them from truly natural
fibers such as cotton, wool, silk, flax, etc
Classification:
Man made fiber can be classified into three classes:
a. Those made from natural polymers.
b. Those made from synthetic polymers.
c. Those made from inorganic materials.

12. Classification flowchart of man made fiber
Man Made Fibres
Organic
By transformation of
natural polymer
Viscose
Cupro
Acetate
Triacetate
Lyocell
Modal
Elastodiene
Inorganic
From synthetic
polymer
Polyester
Polyamide
Acrylic
Modacrylic
Polypropylene
Polyethylene
Elastane
Aramid
Carbon
Ceramic
Glass
Metal

13. Flow chart of synthetic process of man-made fiber:
Synthetic fiber has its beginning with chemistry
A media is developed & is filtered under pressure
It is then extruded into continuous filaments
The filaments are allowed to solidify
Then they are stretched
A finishing solution is then applied
Then the bundle of filaments is crimped
Cutting the bundle into staple length.

14. Different types of man made fiber.
Regenerated Fiber: The man-made fibres, derived from naturally occurring
polymers are known as regenerated fibres. For instance rayon and acetate are
made of the same cellulose polymers that make up cotton. In the case of rayon
and acetate, the cellulose is acquired in an altered state usually from woodPulp operations.
Synthetic Fiber: Another group of man-made fibres is the synthetic
fibers. Synthetic fibres are made of polymers that do not occur
naturally. They are produced entirely in the chemical plant or
laboratory, almost always from by-products of petroleum. Fiber
produced from these polymers include nylon, polyesters, acrylics, the
polyurethanes, etc

15. Inorganic Fiber: The man made fiber ,derived from inorganic substance is
called inorganic fiber.Glass , Carbon, Ceramic & Metal are the example of
inorganic fiber.
Basic Characteristics: A synthetic polymer must have to have suitable
characteristics with respect to several physical and chemical properties.
These are:
a. A high softening point.
b. Adequate tensile strength .
c. Soluability or melting ability for spinning.
d. A high modulus or stiffness.

16. In addition to the primary requirements, many other
properties of the material are important
Chemical
Physical
Biological
Fabric Properties
Stability towards
-acids
-bases
-solvents
-bleaches
-heat
-sunlight
-ageing
-flammability
-dyeability
Mechanical
-tenacity
-elongation
-stiffness
-abrasion resistance
-tensile recovery
Thermal
-melting point
-softening point
-glass transition
temperature
-decomposition
temperature
Electrical
-surface resistivity
Toxicological
Dermatological
Resistance to
-bacteria
-molds
Appearance
-drape
-hand
-lustre
Comfort
-warmth
-water sorption
-moisture retention
-wicking
Stability
-shape
-shrinkage
-felting
-pilling
-crease resistance
-crease retention
-insects

17. Influence of chemical structure on properties
Olefins (alkenes), a family of hydrocarbon compounds—which are produced from the refining of
petroleum and natural gas —contains one double bond between two carbon atoms. The
general chemical formula can be represented as CH2=CHR, with R representing any of
several possible atoms or groups of atoms.
As the repeating unit of a polymer,
CH2
CH
the compound has the following chemical structure:
n
Polypropylene is a material of moderately high melting
R
temperature (176 °C) that can be melt-spun into fibres
useful for several types of clothing, upholstery, carpets, and nonwoven fabrics. When R is
hydrogen (H), the polymer is polyethylene, a relatively low-melting material (137 °C) that
finds use as a fibre in industrial applications—e.g., nonwoven fabrics—but not in most
household applications.
Still another variation is found when R represents a cyano, or nitrile, group (-C≡N), containing
carbon and nitrogen linked by a triple bond. In this case the polymer obtained
is polyacrylonitrile, an acrylic that does not melt without decomposition and therefore must be
solution-spun into fibres used in clothing, drapes, and carpets.
It is observed from the structural variations that the methyl and cyano groups in polypropylene and
polyacrylonitrile raise melting points.

18. Different Types of Spinning
There are typically three types of spinning for polymers: Melt, Dry and
Wet.
▪ Melt spinning is used for polymers that can be melted easily.
▪ Dry spinning involves dissolving the polymer into a solution that can
be evaporated.
▪ Wet spinning is used when the solvent cannot be evaporated and
must be
removed by chemical means.

19. Melt spinning
Melt spinning is the preferred method of manufacture for polymeric fibers. The
polymer is melted and pumped through a spinneret (die) with numerous holes
(one to thousands). The molten fibers are cooled, solidified, and collected on a
take-up wheel. Stretching of the fibers in both the molten and solid states
provides for orientation of the polymer chains along the fiber axis. Polymers
such as poly(ethylene terephthalate) and nylon 6,6 are melt spun in high
volume.

20. Dry Spinning
Dry Spinning: In dry spinning the fibre-forming substance is dissolved in a
solvent before the solution is extruded. As the jets of solution emerge from the
spinneret, a stream of hot air causes the solvent to evaporate from the spinning
solution, leaving solid filaments. Acetate is dry spun by extruding acetone
solutions of cellulose acetate into hot air.

21. Wet Spinning
Wet Spinning: In wet spinning the solution of fibre-forming material is extruded into a
coagulating bath that causes the jets to harden as a result of chemical or physical
change.Viscose, for example, is wet spun. The solution of cellulose xanthate is
extruded into an aqueous solution of acids and salts, in which the cellulose is
regenerated to form solid filaments

22. Comparative features of melt, dry and wet spinning
Features
Melt
Dry
Wet
Investment Cost
Low
High
Low
Hazard
Non-toxic
(Risk of explosion)
Toxic
Heat of Spinning
High
High
Low
300-900
20,000-75,000
2500-3000
ft/min
150-300 ft/min
Spinneret Hole
Spinning Speed
2 to many
thousand
2500-3000
ft/min
Toxic

23. Manufacture of viscose rayon
Viscose rayon is a regenerated cellulose fibre. Because it is produced from naturally
occurring polymers.The raw materials for viscose rayon may be cotton linters, the
short fibres adhering to the cotton seed, or wood pulp derived from northern spruce,
western hemlock, eucalyptus, or southern slash pine. The pulps of these soft woods,
containing about 94 percent cellulose, are especially suited to fibre manufacture.
Wood contains other substances like lignin, besides cellulose. So it is purified, treated
with caustic soda, which converts it into alkali cellulose, then treated with carbon
disulphide, which converts it into sodium cellulose xanthate and then dissolved in
dilute solution of caustic soda. The solution is then “ripened” and then spun into an
acid coagulating bath, which precipitates the cellulose in the form of a viscose
filament.

24. Manufacture Process Flow Chart
Preparation of the wood pulp
Conditioning of Wood Pulp
Steeping (formation of soda cellulose)
Shredding (cutting)
Ageing
Churning (Xanthation or Sulphidising)
Mixing (dissolving)
Ripening
Spinning
Wind up/Cutting