Animal Fibre – Wool: Types, Properties, Processing, Uses

The hair of wool-producing animals such as sheep, angora rabbits, goats, alpacas, and camels are used to make wool fibres. Fleece refers to the wool coat of certain animals. In winter, this coat keeps human bodies warm. To keep warm, prehistoric people covered their bodies with the skin of sheep or other animals. This may have inspired them to turn this animal fibre covering into yarn and textiles. In this article, let’s discuss everything about on particular Animal Fibre – Wool in detail.

What are Animal Fibres?

Wool and silk are animal fibres. All animal fibres are made from proteins. Hair on the body of most animals is keratin, a tough protein material. Wool is obtained from fur (hair) of sheep, Angora goat, cashmere goat, yak, rabbit, camel, llama, and alpaca.

Silk is obtained from cocoons of silkworms.

Types of Animal Fibres

Natural fibres are threads obtained from plants and animals. The fibres are obtained from plants that are used to make fabric (or cloth). For example, cotton plants give us cotton fibres used for making cotton fabrics (or cotton cloth). Cotton, flax and jute are all plant fibres. The fibres are obtained from animals and are hence called animal fibres. The two important animal fibres are:

1. Wool,
2. Silk

The wool comes from animals such as sheep, goats and yak, etc., whereas silk comes from silkworms. So, wool and silk are animal fibres. Wool is used for knitting sweaters and weaving shawls and other woollen cloth. Silk is used for making saris and other dresses. We will now discuss the production of wool in detail.

Wool

Wool is the yarn woven from the fine under hair of those animals which have soft fur or fleece.

Wool Yielding Animals

Wool is obtained from several breeds of sheep. In addition, some breeds of angora or cashmere goat, yak, Bactrian camel, angora rabbit, llama and alpaca also provide wool.

Wool Obtained from Different Animals

1. From Sheep: Sheep have two types of hair that form the fleece:
   Outer coarse hair is known as kemp. The undercoat of fine soft hair close to the skin.
2. From Goat: Wool is obtained from the undercoat of goats. Cashmere goats yield pashmina wool. Angora woolis obtained from the angora goat. These goats are reared in Jammu and Kashmir.
3. From Angora Rabbit: Angora wool is obtained from the soft white fur of the angora rabbit. It is a fine quality of wool.
4. From Yak: Yak occurs in Tibet and Ladakh. The wool obtained from the yak is brown or blackish in color.
5. Llama and Alpaca: They are found in South America. They belong to the camel family. They have soft and fine hair. The yarns are spun from the fleece of these animals. They are very soft and warm.

A list of Indian breeds of sheep

Examples of Animal Fibres

Camel, llama and yak are some animals that yield wool.

Physical Properties of Wool

Wool has the following physical properties.

1. Smoothness: A wool fibre feels smooth to the touch.
2. Tensile strength: It has a very high tensile strength, i.e., it can bear a great pull without breaking. It can increase in length by up to \(70\%\) when pulled in water. Kept stretched in boiling water for about half an hour, the fibre does not return to its original length.
3. Absorption of water: Wool absorbs more water than any other fibre. It absorbs up to one-third of its weight of water.

Chemical Properties of Wool

Wool has the following chemical properties.

1. Action of heat: It starts changing colour at \(100\,^\circ {\rm{C}}\) but does not catch fire easily. It also becomes yellowish when left in a hot, humid atmosphere for a long time. So, the wool on the body of a sheep living in a hot, humid region may be yellowish.
2. Action of acids and bases: It dissolves in acids and alkalis.
3. Action of bleaching agents: The fibre can be bleached without loss of strength.

Production of Wool

Sheep provide the majority of the wool. Sheep are raised and bred for wool, and their hair is clipped and processed into wool. We’ll start with sheep rearing and breeding, then move on to how sheep’s hair (called fleece) is chopped and processed to generate wool (or wool yarn).

Rearing and Breeding of Sheep

Sheep rearing include taking care of the sheep by providing them with food, shelter, and health care. Shepherds are the people who look after the sheep (or rearers). Sheep are herbivores who prefer grass and leaves to eat.

Shepherds therefore transport their flocks of sheep to the countryside to graze. The sheep are fed a mixture of pulses, corn, jowar, oil cakes (the material left over after the production of oil from oil-seeds), and minerals in addition to grazing grass.

Sheep are housed within during the winter and given leaves, grains, and dry forage. Certain breeds of sheep have a thick coat of hair on their body which yields good quality wool in large quantities. These are called sheep of good breeds. Such sheep are ‘selectively bred’ by choosing at least one parent sheep of good breed.

Sheep breeding is done to create breeds of sheep that produce high-quality wool in huge quantities. As a result, both the quality and quantity of wool produced improve.

The hair of the reared sheep is chopped off once they have established a thick covering of hair in order to obtain wool. Fleece is a sheep’s cut-off ‘wool coat’ (together with a thin covering of skin). Soft woollen fibres make up the fleece. Sheep’s fleece is normally retained ‘in one piece.’

How Wool is Obtained from Sheep?

The steps involved in wool production are as follows:

Shearing

The process of removing and collecting the hair from the animal is called shearing. This is done without harming the animal by using shearing tools. These tools are similar to the common shaving machines used by barbers. Shearing is usually done during the summer season. This allows animals to grow back hair by the time winter arrives. The amount of wool produced by one sheep varies from \(1\) to \(3\;\rm{kg}.\)

Scouring

Wool obtained after shearing of sheep is called ‘raw’ or ‘grease wool’. It contains dust and dirt, therefore, requires thorough cleaning. This is called scouring. This makes the wool suitable for making fabric. Scouring involves washing the shorn wool in hot water and detergent and then drying.

Sorting and Grading

After scouring, some wool gets damaged. The damaged or inferior wool is carefully removed. This process is called sorting. The wool is also sorted according to the length, colour and texture of fibres. This is called grading. The grade of the wool determines the price of the wool. The fine wool is priced high. Fine wool is used to make lightweight textiles.

Carding

Before the wool can be used for making fabric, it is straightened and cleaned. The tangled fibres are separated to form continuous fibres. This process is called carding. In carding, the wool fibres are passed through a series of metal teeth to straighten the fibres. The woollen fibres are given different colours using dyes or chemicals.

Spinning and weaving

Carded wool is then stretched and twisted into a thin yarn. These thin yarns are spun and joined together to form a single strand of yarn. Woollen yarn is woven or knitted into fabric, which is then used to make finished products such as clothes and bags.

Uses of Wool

1. Fabrics, shawls, blankets, carpets, felt (compressed wool), and upholstery are all made from wool.
2. Piano hammers are covered with wool felt. It’s also utilised in heavy machines and stereo speakers to absorb noise.
3. The used wool is used to make shoddy. The current wool fabric is chopped into small pieces and then carded to make shoddy. After that, the carded wool is spun into yarn. This yarn is inferior to fresh wool and is used to make low-cost woollen clothing and blankets.

Australia is the largest producer of wool, followed by former Soviet Republics, New Zealand, China, Argentina, South Africa and Uruguay.

Quality of Wool

The quality of wool is judged by the wool length, diameter, elasticity, strength, durability, effectiveness as an insulator and its ability to take up colouring dyes.

Summary

Wool, as we know, comes from sheep and some other animals. The other animals are goats, antelopes (deer-like animals), llama, rabbit and yak. Wool is the fleece covering the entire skin of the animal. Fleece protects the body of the animal.

Wool is present as a thick coat of hair on the body of wool yielding animals. Air gets trapped in the spaces between the wool fibres and does not allow the body heat to escape as it is a bad conductor of heat. Hence woollen clothes keep us warm in winter. This article learns about the different examples of wool fibres, properties of wool fibres, processing of wool and uses of wool.

FAQs on Animal Fibres – Wool

The most commonly asked questions about wool are answered here: