Material guide – Wool

A popular material throughout history

Wool is a natural, renewable raw material and refers to the soft hair of the undercoat (as opposed to the top hair) of sheep in particular. There are, however, other animals whose wool is used to produce textiles, e.g. cashmere goats (cashmere wool), angora goats (mohair), angora rabbits (angora), camel breeds (alpaca wool and camel hair), musk oxen (quiviut) or yaks (yak's wool). There have been sheep in Europe and Asia for around 2.5 million years. However, before the Ice Age, they were the size of oxen. In around 9,000 BC, the first sheep were kept and bred in South East Asia and were used as the first pets that clothed and fed humans. Wool has been used for clothing for around 10,000 years and is the oldest textile raw material. Even today, despite our new synthetic fibres and widespread cotton, it is still very important in the international economy. Sheep are kept almost everywhere in the world, including in Germany.

Wool as an imported fabric

Nevertheless, wool for textiles is mostly imported, primarily from Australia, New Zealand, South America and South Africa. During the Iron Age and before the invention of scissors, wool was plucked from the animals, and only later was shearing possible. Sheep can be shorn once or twice a year, but nowadays most are shorn using an electric shearing machine so as to not harm the animal. This results in the wool being removed as a continuous pelt (fleece).

Differences in wool quality

Wool has different qualities and value depending on the body part it is shorn from. The most valuable wool is taken from the shoulder area, but the neck and sides also provide high quality material. There are also different wool qualities, depending on the breed of the sheep. The most high quality wool comes from Merino sheep. After shearing, the wool is washed thoroughly and cleaned of dirt residues, dried and can then be spun into thread. Depending on its intended use and the specific properties of other fibres, wool is often blended with other materials such as cotton, polyester or polyamide.

Wool has lots of great properties

The properties of wool are largely thanks to the special structure of the wool fibres, which consist of the outer shell cuticle and the trunk cortex. The interplay between these two sections of the fibre create the wool's specific moisture management. The outer shell is hydrophobic and therefore repels moisture, but allows water vapour to penetrate into the cortex. This means that wool can absorb around 35% of its own weight in water into its interior, without feeling wet. Furthermore, it can conduct away moisture significantly more rapidly than, for example, much-used cotton. In addition, the wool fibre has a mechanical self-cleaning function, as the entangled fibre types located in the cortex begin to swell to different degrees when moisture absorption and release occurs. This means the wool fibres are set in motion, which leads to dirt particles being repelled. Dirt is also unable to penetrate into the interior of the fibre, meaning that textiles made from wool do not become dirty quickly.

Naturalness proves itself

Unlike synthetic fibres, wool absorbs virtually no odours and any odours are quickly released back into the air, so that wool products smell neutral again after a short time in fresh air. In addition, wool fibres are up to 85% air and therefore insulate heat well. This means the body heat is retained beneath the fabric, reflected and does not escape much. Wool fibres are very stretchy and therefore do not wrinkle much, so woollen products do not need to be ironed. They are also antistatic, colour-fast and repel sweat. Another important property is that wool has low flammability. It simply chars and does not burn. However, wool does tend to pill, but this can be reduced by using special equipment. Wool also tends to feel scratchy and uncomfortable against the skin, but this can be reduced by using special techniques.

Textiles made from wool should only be washed by hand or at a maximum of 30° on the washing machine's wool cycle with a wool detergent. Garments should always be turned inside out before washing to protect them and not rubbed or wrung out. After washing, the fabric should be thoroughly rinsed with cold water and carefully rolled up in a hand towel to squeeze out the majority of the liquid.

Take care when drying

In addition, wool garments should never be put into the tumble dryer, left in the bright sunshine or dried on radiators; they are best left to dry lying on a clothes horse. When ironing, the steam setting and light pressure are sufficient. When ironing without steam, place a damp cloth between the garment and the iron to prevent an undesirable sheen.

Hardly any other fibre, whether synthetic or natural, has as many positive attributes as wool. Wool is very versatile and can be used in all clothing textiles. Thanks to its good thermal insulation and low flammability, wool is also often used as a fire protection and insulation material. Wool is also widely used for blankets, furniture upholstery, carpets, mattresses and workwear. It is also used for padding in the vehicle and aircraft industry. Despite its many advantages and positive attributes, wool is used far less than cotton and synthetic fibres in textile production. This is due partly to the fact that wool is not an easy-care material, and can also feel slightly scratchy on the skin and pills quickly.