Wool fibre

All about wool fiber

1. WOOL FIBER

2. Wool is animal fibrous protein fiber . It comes from fibrous covering of the sheep, goat, camel etc. For thousands of year wool has been used for clothing around the world. Till today wool fiber has great importance because of its unique natural properties that are absent in other natural and synthetic fibers. What is WOOL?

3. Wool and hair both are protein fiber comes from fibrous covering of sheep, goat, and camel. But wool fibers have some special characteristics that are absent in hair. Wool are short, fine, curly, elastic but hair are long, coarse, less elastic, no scale and stiffer than wool. Wool and Hair:

4. Wool Producing Countries:

5. Physical Structure:

6. Polymer System: The wool polymer is linear keratin polymer , with some very short side groups and it normally has a helical configuration. The repeating unit of the wool polymer is the amino acid which has the general formula shown in fig.

7. Hydrogen bond(H-bond) Salt linkage or ionic bonds. Cross-linkage and cystine linkage Vander walls forces. The polymer system of wool is extremely amorphous. It is about 25-30% crystalline and 70-75% amorphous. Different Bond in Wool Polymer:

8. Chemical Composition of Wool:   Component % Wool keratin 45 Wool wax 18 Suint 12 Water 12 Debris 15 Approximate composition of raw wool

9. Elements % Carbon 50 Oxygen 22-25 Nitrogen 16-17 Hydrogen 7 Sulfur 3-4 Keratin:

10. Manufacturing Process:

11. Triming : By this process farmers collect wool from sheep. It’s also called sheering. The sheep is sheared by early spring. Sorting: Wool sorting is done by good skilled workers who shorts according to fineness length and sometimes strength of fiber. Scouring: It involves washing in warm soapy water several times to remove the natural grease or gum from the fiber and the saint dirt and dust. Manufacturing Process:

12. Oiling: The wool fiber is treated by various oil including animal vegetable and mineral because unmanageable. Garneting: The picking and shredding process of recycled and unused wool is called garneting. Carbonizing: After garneting the wool fibers are put through a dilute solution of HCl or H 2 SO 4 Which destroys any vegetable fibers is called carbonizing. Manufacturing Process:

13. Physical Properties: 1.Length and fineness :- Merino wool fibers are very fine (17-25 micro meters) but not very long (60-100 mm) whereas Lincoln wool is coarser ( around 40 micro meters) diameter but much on length. ( 75- 250 mm). 2.Crimp :- The crimp of wool fibers is most pronounced in the fine wool fibers. For example , the best merino wools will have 12 waves to the cm ( 30 per inch) in a fiber. The elasticity of wool fiber is due to it's crimp . Due to the crimp , wool yarn trap air and when used in garments .

14. Physical Properties: 3.Luster :- Wool fiber have natural luster. Luster depends very largely on the nature of the fiber surface. 4.Color :- Most of the wool from modern sheep is white or near -white in color. 5.Tenacity :- The low tensile strength of wool is due to the relativity few hydrogen bonds that are formed. Wool has a tenacity of 8.8-15 CN/Tex in dry state and 7-14 CN/Tex in wet state.

15. Physical Properties: 7. Elastic property :- Wool fibers are highly elastic and resilient because of it's crimped configuration and partly to the alpha-keratin configuration of wool polymers. The elastic recovery of wool fibers is 99% at 2% extensions. 8. Effect of moisture and water :- Under Ordinary atmospheric conditions, Wool will hold 16-18% of it's weight of moisture. 9.Specific gravity :- Wool is a light-weight fibre of specific gravity 1.32

16. 1. Effect of acid :- Wool is decomposes completely by hot concentrated H 2 SO 4 but general resistant to other mineral acids. 2. Effect of alkalis :- Caustic soda, Ammonium carbonate, Borax and Sodium phosphate have minimum effect of wool because the chemical nature of wool fibre is keratin. 3. Effect of bleaching:- Hypochlorite bleaching damage the wool fibre . Normally hydrogen peroxide is used for bleaching. CHEMICAL PROPERTIES

17. 4. Effect of organic solvents:- Wool has a good resistance to dry-cleaning and other common solvents. 5. Insects:- Wool is attacked by moth-grubs and other insects. 6. Micro Organism :- Wool has a poor resistance to mildews and bacteria and it is not advisable to leave wool for too long in a damp condition. 7. Dye ability:- Easy to dye. Acid , mordant, reactive dye is suitable. 8. Effect of heat:- Wool becomes weak loses its softness when heated at the temperature of boiling water for long periods of time. At 130 ○C ,it is decomposes and turns yellow,and it chars at 300 ○c . CHEMICAL PROPERTIES

18. The classification by fleece is as follows:   Lamb’s Wool: The fleece obtained by shearing the lamb of six to eight months old for the first time is known as lamb’s wool.   Classifsication of wool: Hogget Wool: Hogget wool is the one obtained from sheep about twelve to fourteen months old that have not been previously shorn.These are primarily used for warp yarns.

19. Weather Wool : Weather wool is the one obtained from the sheep older than fourteen month. These fleeces contain much soil and dirt. Pulled Wool: Pulled wool is taken from animals originally slaughtered for meat. The wool is pulled from the pelt of the slaughtered sheep using various chemicals. The fibers of pulled wool are of low quality and produce a low-grade cloth.

20. Dead Wool: This is the wool obtained from the sheep that have died of age or accidentally killed.Dead wool fibre is decidedly inferior in grade; it is used in low-grade cloth Cotty Wool: This type of wool is obtained from the sheep that are exposed to severe weather. As discussed; the severe weather conditions hamper the qualities of the fleece obtained. The cotty wool is of a poor grade and is hard and brittle

21. 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 The varieties of merino sheep are chiefly found in Spain, New Zealand, South America, South Africa and Australia Classification of Wool(by sheep):

22. 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 Classification(by sheep):

23. c. Class three wools: This class of sheep originated in the United Kingdom. The fiber are about 4 to 18 inches long ( 100455 mm ) . These are coarser and have less crimps and scales. As a result they are smoother and have more luster . Classification(by sheep):

24. 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. Classification(by sheep):

25. Wool Processing(fleece-fabric):

26. Wool is spun into two types of yarn. 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 Types of Wool Yarn:

27. 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 Types of Wool Yarn:

28. Woolen yarn Worsted yarn Short staple fiber Long staple fiber Only carded Carded and combed Slightly twisted Higher twisted Coarser yarn Finer Weaker Stronger Difference between Wollen and Woested :

29. 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 Sources of Wool Fiber:

30. Sources Fiber Product

31. Source Fiber Product

32. Wool is Natural Renewable Sustainable Biodegradable Energy efficient Wool is Healthy Breathable Humidity control Low allergy Toxic chemical absorption Sound reduction Wool is Safe Flame resistant UV protection Static electricity reduction High thermal resistance Advantage of Wool Fiber:

33. Apparel: Suits, jackets, pullovers, coats, sportswear, skiwear, scarves, gloves, socks, hats, active wear, children's wear, waterproof fabrics, casual wear, shoes, formal wear etc. Interior Textiles: Carpets, duvets, mattresses, pillows, blankets, upholstery, tapestries, lamps, rugs, futons, bedspreads, tablecloths, wall coverings etc. Technical Textiles: Aircraft interiors, thermal insulation, sound insulation, sound vibration control, roof insulation, filtration, fire proof wear, police uniforms etc. Application of Wool:

34. Prepared by: Tanmoy Choudhury B.Sc. in Textile Engineering BGMEA University of Fashion and Technology; Bangladesh