The fiber textile obtained from animals such as sheep is called wool. It also includes animals such as camelid wool, angora from rabbits, qiviut from muskoxen as well as mohair and cashmere from goats. There are many different qualities that wool has that make it different from fur or hair. For one thing, wool is elastic and crimped.
Skin follicles produce wool. These are located on the skin’s uppermost layer and pushed lower into the dermis when the fibers of wool grow. There are secondary and primary follicles. There are three fiber types produced by primary follicles. These include true wool fibers, medullated fibers, and kemp wool. True wool fibers are only produced by secondary follicles. The crimp and scaling of wool make it easily spun into fleece since each fiber attaches to each other. Wool fabrics have more bulk than other fabrics due to their crimp. Wool can also hold air, which helps in heat-retention. There is a high heat coefficient with wool, so it does not release heat. This is an advantage for people that need insulation including the Tuaregs, Bedouins, and other desert people.
Wool felting happens when wool fibers hook together after getting hammered. The crimp amount is related to the wool fiber fineness. Merino and other fine wool have up to a hundred times more crimp per inch. Karakul and other coarse wool might have as little as two crimps. On sheep, Kemp is what fleece is called. Depending on the breed of sheep, fleece can be used for carding, felting or spinning into quilt batts or other products for insulation including the famous Scotland tweed cloth.
Moisture is readily absorbed by wool fibers although these are not hollow. Moisture can be absorbed by wool up to a third of its own weight. Like many other fabrics, wool absorbs sound as well. It has a creamy general color although random colors like silver; brown and black are also naturally produced by sheep.
Compared to cotton, wool ignites at high temperatures. There is a low flame spread rate and a lower combustion heat and heat release compared to cotton as well. For environments that require higher safety, wool carpets are the recommendation. Also, for environments such as aircraft and trains, wool is the preferred carpeting of choice. For soldiers and firefighters that are exposed to a high fire likelihood, wool is the specified garment of choice as well.
Aside from being used for clothes, wool is also used for upholstery, insulation, felt, carpeting, saddle cloth, horse rugs, and blankets. Wool felt covers hammers in a piano and is used for absorbing noise in heavier speakers. Helmets were lined with wool in ancient Greece. Traditionally, wool was used to cover diapers made of cloth. Since wool repels water and the interior absorbs, it is a good choice for covering wet diapers, so the outer garment remains drier. Wool can also be dyed any color of your choice from a reputable dye supplier