Wool is a natural fiber obtained from sheep and other animals, primarily composed of protein and amino acids, with major production in countries like the UK, Australia, and New Zealand. Various types of wool are classified based on sheep breed and fleece, with processing steps such as scouring and combing to ensure quality, leading to woolen and worsted yarn. Wool offers numerous benefits including being biodegradable, breathable, and energy-efficient, and is used in diverse applications from apparel to technical textiles.

1. WOOL

2. Wool
Wool and hair fiber are the natural hair of
certain animals and are composed of protein.
Protein consists of complex organic
compounds containing amino acids.
The chief wool producing countries are UK,
Australia, New Zealand, Argentina, South
Africa and United States.

3. Wool
Wool and hair fiber are the natural hair of
certain animals and are composed of protein.
Protein consists of complex organic
compounds containing amino acids.
The chief wool producing countries are UK,
Australia, New Zealand, Argentina, South
Africa and United States.

4. Wool
Wool and hair fiber are the natural hair of
certain animals and are composed of protein.
Protein consists of complex organic
compounds containing amino acids.
The chief wool producing countries are UK,
Australia, New Zealand, Argentina, South
Africa and United States.

5. Cross sectional view

8. Wool
The sources of wool fiber are:
1. Camel hair
2. Mohair ( obtained from Angora goat )
3. Cashmere ( obtained from Cashmere goat )
4. Llama ( obtained from camel like animal )
5. Alpaca ( obtained from domesticated
animal that resembles llama.

9. CashmereAngora

14. Wool
Classification of Wool:
The sheep may be classified into four types.
1. Merino Wool:
Merino wool ( obtained from Merino sheep) is
considered as best quality wool.
Fiber is strong, fine and elastic.
Merino is used in the best types of wool
clothing.

15. Wool
The staple of Merino wool is relatively short ( 25-
125 mm ). The staple is relatively ranging from 1-
5 inch.
The varieties of merino sheep are chiefly found
in Spain, New Zealand, South America, South
Africa and Australia.

16. Wool
b. Class-Two Wool:
This class of sheep is originated in England,
Scotland, Ireland and Wales.
The staple fiber is relatively longer than
Merino ( 50- 200 mm). It is 2-8 inches.
The fibers are strong, fine and elastic but not
as strong, fine and elastic as merino. It has
scales and crimps but not as more and goods
as merino wool.

17. Wool
c. Class three wools:
This class of sheep originated in the United
Kingdom.
The fiber are about 4 to 18 inches long ( 100-
455 mm ).
These are coarser and have less crimps and
scales.
As a result they are smoother and have more
luster.

18. Wool
d. Class- four wools:
This class of wools are 25-400 mm long (1-16
inch), coarser and hair like having less scales
and little crimp.
Therefore, these wools are smoother and
more lustrous having less strength and
elasticity.

19. Wool
Classification by fleece:
Fleece is the coat of wool shorn from the
sheep at a time.
1. Lamb’s wool:
The first fleece sheared from a lamb about
6-8 months old is known as lamb’s wool or
sometimes referred to as fleece wool or first
clip. Lamb’s wool is immature and not strong
as fully developed wool of same sheep.

20. Wool
2. Hoggest wool:
Hoggest wool come from sheep 12 to 14
months old that have not been previously
shorn. The fiber is soft and fine.
3. Wether Wool:
Any fleece clipped after the first shearing is
called wether wool.
This wool is usually taken from a sheep older
than 14 months.

21. Wool
4. Pulled wool:
When sheep is slaughtered for meat, their
root are pulled. Such wool is called pulled
wool fiber and is inferior for two reasons.
1. Sheep that are raised for meat generally do
not have a good quality of wool.
2. The roots of fibers are damaged by
chemicals and tension exerted in pulling.

22. Wool
5. Dead wool:
The wool recovered from a sheep died or
killed accidently.
6. Cotty wool:
Sheep that are exposed to severe weather
conditions or lack of nourishment yield a wool
that is hard and brittle.

23. http://biotechlearn.org.nz/focus_stories/wool_innovations/wool_processing_fleece_to_fabric

24. • Scouring
if we didn’t wash our hair for a year, imagine what
our hair would be like??????
“Sheep has that same issue”
The scouring process – Just like washing,
Because the sheep picks up contaminants such as dirt
and also releases sweat and grease, so that has to be
removed.

25. • Gilling
Gilling is a process of aligning the wool fibres so
they are parallel to one another. This is done
using a coarse comb. At this stage, the sliver still
contains particles of vegetable matter as well as
short fibres.

26. • Combing
There’s usually small particles of vegetable
matter – seeds and leaf– picked up by the
sheep.
So combing removes vegetables matters. It also
removes the short fibres, because short fibres
are hard to control in the yarn. It’s much easier
for the spinner to organise longer fibres.

27. Growth of Wool Fiber:
The wool fibers grows up in groups of 5-80
hairs .
There are about 10,000 to 22,000 scales per
square inch.
The average rate of growth of wool fiber is 1
inch in two month.

28. Quality of Wool
The quality of wool varies with;
Breed of sheep.
Conditions under which it has lived.
The quality and price of raw wool depends on;
Fineness
Length
Strength
Purity
Color

29. Fineness - fiber diameter
Thicker Thinner
Fine
$$$$
Crossbred
Medium
Long
Coarse
Grade refers to the relative diameter of the wool fibers (fineness).
< 17µ> 40 µ

30. Average Fiber Diameter ( Microns) Wool Grades
Under 17.70 Finer than 80’s
17.70-19.14 80’s
19.15-20.59 70’s
20.60-22.04 64’s
22.05-23.49 62’s
23.50-24.94 60’s
24.95- 26.39 58’s
26.40-27.84 56’s
27.85- 28.29 54’s
29.30-30.99 50’s
31.00-32.69 48’s
32.70-34.39 46’s
34.40-36.19 44’s
36.20-38.09 40’s
38.10-40.20 36’s
Over 40.20 Coarser than 36’s

31. Types of wool Yarn
Wool is spun into two types of yarn.
1. Woolen yarn:
Woolen yarn is thick, and fibers in woolen
yarn are held loosely and subjected to only
limited twist during spinning.
These yarn are woven into thick bulkier
material.

32. 2. Worsted yarn:
Worsted yarns are finer, smoother and
stronger than woolen yarns.
The fibers in worsted yarn are twisted strongly
to form fine and strong yarn.
These yarns are woven into fine dresses.

34. Properties of Wool
Tensile strength:
Wool has tensile strength of 17000-29000 lbs
per square inch.
Elongation:
Wool has an elongation at break 25-35 %
under standard conditions of testing.

35. Elastic properties:
Wool is an elastic fiber. It has elastic recovery
of 99 % at 2% extension and 63 % at 20%
extension.
Specific gravity:
It has specific gravity of 1.32.
Effect of moisture:
Moisture regain of wool is 16 %.

36. Effect of heat:
At 130 degree centigrade, it decomposes and
turns yellow.
Wool becomes weak and loses its softness
when heated to temperature of boiling water
for long period of time.

37. Effect of age:
Wool shows little deterioration with age when
stored carefully.
Effect of sunlight:
Wool is weakened by prolonged exposure to
sunlight. The wool becomes discolored and
develops a harsh feel.

38. Effect of Acids:
Wool is attacked by hot sulphuric acid and
decomposes completely.
Dilute acids are used for removing impurities
without damaging the wool fibers.

39. Effect of alkalis:
Unlike cotton, structure of wool is sensitive of
alkaline substances.
Wool will be dissolved by caustic soda
solutions. The scouring and bleaching of wool
is carried under low alkaline solution like
sodium phosphate and ammonium carbonate
which have minimum effect on wool.

40. Effect of insects:
The proteins of wool is a modified form of
meat so it can be easily attacked by moth
grubs and other insects.
Micro organisms:
Wool has a good resistance to mildews and
bacteria.

42. Advantages of Wool fiber
• Wool is Natural
Renewable
Sustainable
Biodegradable
Energy efficient
• Wool is Safe
Flame resistant
UV protection
Static electricity reduction
High thermal resistance
• Wool is Healthy
Breathable
Humidity control
Low allergy
Toxic chemical
absorption
Sound reduction

43. Applications of wool
Apparels
Technical Textiles
Interior Textiles
http://www.iwto.org/wool/wool-applications/

44. Apparel:
Suits, jackets, pullovers, coats, sportswear, skiwear, scarves, gloves, socks, hats,
active wear, children's wear, waterproof fabrics, casual wear, shoes, formal wear, hand
knitting wool, uniforms.
Interior Textiles:
Carpets, duvets, mattresses, pillows, blankets, upholstery, tapestries, lamps, rugs,
futons, bedspreads, tablecloths, wall coverings, sofas.
Technical Textiles:
Aircraft interiors, thermal insulation, sound insulation, sound vibration control, roof
insulation, filtration, fire proof wear, police uniforms, military uniforms, air conditioning,
bandages, second skin injury prevention, piano felts, wool filters for dust chemical
odours, billiard cloths, automotive composites, tennis balls