Wool is the protein fibre obtained from sheep and certain other animals. The wool from sheep is different from the wool from other animals; goats produce cashmere and mohair, and rabbits produce Angora. 75% of wool comes from Australia, New Zealand, Argentina, South Africa, and Uruguay.
How It Is Made
Different geography areas have different breeds of animals, each suited for the climate and land type. This is just one of the many factors that will affect the quality of wool fabric; the breed of the animal, its physical condition, where on the animal the wool is obtained from, and the finishing processes.
The natural colour of wool fibre can vary from white, near white brown to black. It is available in many different weights, along with different textures.
Wool takes dye well and evenly and is available in a whole palette of colours. The fibres are hydrophilic meaning they repel water. Initially the water will lie on the surface of the fabric (you can brush it off!). Once the water seeps into the fabric it will readily absorb it. Wool can absorb almost one-third of its own weight without feeling damp or clammy. Once a stain has set into the wool, it can be difficult to remove. A common stain is perspiration, which can cause discoloration. Wool is great in absorbing perspiration and keeping a layer of dry air next to the skin; so whilst it can stain, it is also great for helping you to stay dry.
The wool fabrics adhere dirt and requires to be thoroughly cleaned. Care should be taken while laundering as the fibre is softened by moisture and heat. Wool is weaker when wet, losing about 25 percent of its strength, so be careful. It can result in shrinking and felting of the fabric. Thus wool fabrics should never be pulled or wrung while wet. They should be lifted and squeezed. Wool shrinks when wash, through dry cleaned wools shrink less.
The wool fibres curl like little coils springs, which create spaces that make wool spongy, and causes it to be more insulating. These “springs” elongate when extended and retract when released. This also allows wool fibres to stretch up to 50% when wet and 30% when dry and still bounce back to their original shape when released. The springs also hold air which causes the fabric to keep heat, though it also used to keep heat out. It’s like built-in climate control!
Wool recovers faster when in a humid environment which is why a steam iron is recommended for pressing wool and steaming a wool garment freshens it. To keep this natural elasticity, hang your woollen garments properly after wearing and allow them to relax sufficiently.
If let damp for a long time, it will be affected by mildew.
Wool is the weakest of all natural fibres. Sometimes it is strengthened by the use of ply yarns – a two ply yarn is stronger than a single twisted yarn.
Wool ignites at a higher temperature than cotton and some synthetic fibres. It has a lower rate of flame spread, a lower rate of heat release, a lower heat of combustion, and does not melt or drip. |t also is self extinguishing For these reasons wool is usually specified for garments for firefighters, soldiers, and others in occupations where they are exposed to the likelihood of fire.
It has a naturally high UV protection and is considered hypoallergenic.
Wool is measured in grades. These grades are based on the measurement of the wools diameter in microns and its style. Any wool finer than 25 microns is generally used for garments, while coarser grades are used for outerwear or rugs. The finer the wool, the softer it is, while coarser grades are more durable and less prone to pilling.
|Grade / Name||Microns|
|Ultrafine Merino||< 15.5|
|Superfine Merino||15.6 – 18.5|
|Fine Merino||18.6 – 20|
|Medium Merino||20.1 – 23|
|Strong Merino||> 23|
|Comeback||21 – 26|
|Fine Crossbred Corriedales||27 – 31|
|Medium Crossbred||32 – 35|
|Downs||23 – 34|
|Coarse Crossbred||> 36|
|Carpet Wools||35 – 45|
Note that downs will typically lacks luster and brightness compared to other wool styles. Some examples of downs are Aussie down, Dorset Horn down and Suffolk down.