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History: />
7000 years ago the history of wool began in Babylon, Egypt and China. Already in the Iron Age cutting tools for wool were invented. In the 14th century Merino wool was bred and in the 18th cenutry there was the beginning of sheep breeding. And today only Australia rears (aufziehen) about 160 million sheep, which is 14 % of the sheep population on the earth.
Wool production:
Shearing: The sheep is shorn by electric shears. The shearing must happen carefully because the coat must be separated intact and the coat is called the fleece. The wool from the legs is short, because of that, this wool is separated.
Classing: After the shearing the wool is divided into 4 categories (1= best; 4= worst). The grader classifies the wool according to fineness, crimp, length, impurities, and colour and the most contaminated place is found in the belly area.
Scouring: The removal of all impurities from grease wool can use water, detergent, and sometimes a mild alkali. The wool weight is 1-6 kg and about 40% of this weight is grease, dirt and burs.
Carbonizing: Wool containing excessive amounts of vegetable material is carbonized using an aqueous acid treatment. This act is done to remove the vegetable material of the wool.
Processing: The wool fibres are spun into fine, smooth yarns by the Worsted process, and into coarser, more bulky yarns by the Woollen process.
Classification of wool:
There are many different types and breeds of sheep, therefore they are classified in five basic types:
Wool types
Fine
Medium, Crossbred
Long ,Coarse
Breed (examples)
Merino
Southdown
Karakul
Length
50 -120 mm
120 - 150 mm
Over 150 mm
Crimp,
Waviness
Highly crimped
Normal crimp
Low crimp
Sources
(examples)
Australia, Africa.
Argentinia, Uruguay
New Zealand, Great Britain
Applicati-ons
Fine outerwear, shawls, socks.
Sporting clothing, is heavier most robust
For carpets and furniture
Wool is also classificated into:
Shearing:
§ Lambswool: from the first shearing, after six months (fine, not very strong, fine tips..)
§ Yearling wool: after first or second shearing 10 - 12 months later
§ Six- month, Eight- month, Twelve- month wool: shorn with six, eight or twelve months' distance.
Source:
Australia, New Zealand, Cape .
Origin:
§ Virgin wool: from living healthy sheep
§ Dead wool, Fallen wool: from sheep that have died form natural causes
§ Skin wool: from the skin of slaughtered sheep
§ Recovered wool: is made of worn clothing which is recovered in a mechanical way.
Recovered wool has a low quality.
Construction of Wool Fibre:
1. scales 2 bilaterial structure 3. Fibrial bundles 4 fibrils 5. protein macromolecule
Clothing Comfort:
Thermal insulation: Bulky woollen yarns have a looser structure and so their air lock is excellent.
Moisture absorption: wool fibre can absorb up to a third of its weight. This is called very good moisture absorption.
Next to skin comfort: Lambswool and Merino wool are very fine, but wools which are coarser can irritate the skin.
Other Important Properties:
Strength: is sufficient, wool is not particularly durable
Extensibility: is very good
Elasticity: is excellent
Felting: is when water, heat and mechanical action act on the clothing.
PRODUCTS MADE OF WOOL:
Apparel Fabrics: pullovers, waistcoats, overcoats, dresses.
Accessories: ties, hats, socks..
Household textiles: carpets, drapes, furnishings
Industrial textiles: fire protection clothing, industrial felts
Typical Wool Fabrics:
Cheviot, Donegal, Flannel, Shetland, Tweed..
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