Wool The Natural Fibre
Limited supply and exceptional characteristics have made wool the world's premier textile fibre
Sheep (Ovis aries) were first domesticated 10 000 years ago.As sheep were among the first animals to be domesticated, the first textiles were probably woven from their fleece. Sheep currently number about 1 billion head, in 200 breeds, worldwide.
Sheep are shorn of their wool usually once a year. After scouring to remove grease and dirt, wool is carded and combed, then spun into yarn for fabrics or knitted garments. Merino sheep produce up to 18 kg of greasy wool a year.
Today wool is still the world’s leading animal natural fibre: its complex protein structure is responsible for unique characteristics and properties – such as exceptional resilience and elasticity – that synthetic fibres just cannot match. Wool has natural crimpiness and scale patterns that make it easy to spin. Fabrics made from wool have greater bulk than other textiles, provide better insulation and are resilient, elastic and durable.
The wool fibre varies from super fine Merino fibre similar to cashmere, to very coarse hairy wools. The diameter of the fibre determines its final use and value. Fibre diameter ranges from 16 microns in superfine merino wool (similar to cashmere) to more than 40 microns in coarse hairy wools.
Some 37% of the world's wool production is classed as fine wools, 22% as medium wools, and 41% as coarse wools.
CNR-ISMAC, Biella, Italy
The world's leading animal fibre, wool is produced in about 100 countries on half a million farms. Major producers are Australia, Argentina, China, India, the Islamic Republic of Iran, New Zealand, Russia, South Africa, United Kingdom and Uruguay. Depending on the country and region, wool producers range from small farmers (above, in Peru) to large scale commercial grazing operations.
Production and Trade
Sheep are usually shorn once a year in the spring/summer months, although in some countries shearing may take place as many as three times a year. Where production systems are advanced, the wool is rigorously tested to determine properties and different grades are packed separately.
The second step in the production chain is known as "early" processing, in which the wool is scoured to remove grease and dirt, carded and combed. It is then spun into yarn for use in fabrics, knitted garments or hand-knitting wool.
The Food and Agriculture Organization of the United Nations (FAO) estimates annual wool production at around 2.1 million tonnes per year. Australia produces one fifth of that total, while China, New Zealand, Iran, Argentina and the UK each produce more than 50 000 tonnes. Exports of greasy plus scoured wool amount to around 800 000 tonnes annually, exported to major textile centres to be spun and woven. China is the primary importer of raw wool (310 000 tonnes in 2007), followed by Italy. The retail value of sales of wool products is around US$80 billion a year.
Uses of Wool
Wool is a multifunctional fibre with a range of diameters that make it suitable for clothing, household fabrics and technical textiles.
Its ability to absorb and release moisture makes woollen garments comfortable as well as warm. Two thirds of wool is used in the manufacture of garments, including sweaters, dresses, coats, suits and "active sportswear". Blended with other natural or synthetic fibres, wool adds drape and crease resistance.
Slightly less than a third of wool goes into the manufacture of blankets anti-static and noise-absorbing carpets, and durable upholstery (wool's inherent resistance to flame and heat makes it one of the safest of all household textiles).
Industrial uses of wool include sheets of bonded coarse wool used for thermal and acoustic insulation in home construction, as well pads for soaking up oil spills.