Page 27 - Curriculum Visions Dynamic Book

(Left and right) Wool is used in sweaters, rugs, and carpets. It has a better feel than many synthetics and can be harder wearing. However, it tends to be expensive, is harder to wash, and is subject to attack by moths.
plant fibres. They are made of overlapping
scales. Most wool diameters are between 16
to 40 microns (millionths of a metre) and
up to 20 cm long. Longer fibres are used for
fabrics called worsteds and for suits and
other smoother fabrics; shorter fibres are used
for tweeds and other coarser fabrics. Natural
wool ranges in colour from white to grey and brown and black.
Wool has good resistance to breaking but is weaker when wet than when dry. Once pulled out of shape, wool will spring back to its original length. This helps the fabric retain its shape during washing and helps in its crease resistance.
Wool also has a natural waviness, or crimp. This means that the fibres interlock easily and leave natural gaps that trap air. That helps the wool appear soft, while the trapped air acts as an insulator and helps the wool feel warm. Wool has quite a low density, so that it can be made into lightweight products. Wool is also easily dyed.
Wool acts as a natural moisture absorber and wick, soaking up moisture from the body and transferring it to the air. Moisture is absorbed and
(Below left) Cashmere is the very fine fibre from the goats that live in the Kashmir Himalayas of Asia.
The hair used to make shawls and other garments is the fine undercoat beneath the coarse wool. It is combed out during the molting season. The fibres it yields are between 3 and 10cm long.
The amounts of this undercoat are small, and one pullover needs the product of about five goats. The hair has scales like that of wool, but finer. The fibres are also finer than any wool, averaging about 15 micrometres in diameter. The most common colour is grey, but hairs can be white, black, and brown.
It is not as strong a fibre as wool, nor does it have the durability of wool. It is therefore exclusively a fashion item.
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