The Natural Fiber

Vegetable Fibers

Of the several vegetable fibers,each drived from a different plant,two are recognize as major textile fibers,cotton and linen.

Cotton

The cotton fiber grows in the scedpod,or boll,of the cotton plant.Each fiber is a single clongated cell that is flat,twisted,and ribbinlike with a wide inner hollow ( lumen).It is composed of about 90 percent cellulose and about 6 percent moisture;the reminder consists of natural impurities.The outer surface of the fiber is covered with a protective waxlike coating, which gives the fiber a somewhat adhesive quality.

The characteristic combined with its natural twist contribute to making cotton an excellent fiber for spinning into yarn.Cotton yarn is used for all types of apparel,home furnishings and industrial applications.

Linen

The linen fiber is obtained from the stalk of the flax plant. The hair like fibers,which are held together by a gummy substance called pectin,comprise the core of the flax stalk.It,too,has a lumen and is composed of about 70 percent cellulose and 30 percent protein,ash,woody tissue and moisture.

Linen fiber is relatively smooth,straight, and lustrous.Linen fiber is more brittle and less flexible than cotton. It is more difficult to prepare and spin into yarn.Linen yarn can be very strong and lustrous, and is used for apparel,home furnishings, and upholstery.

Animal Fibers

There are several animal fibers,each obtained from a different source,but only two are recognized as major textile fibers.They are wool and silk. ( Minor hair fibers-camel.lama,alpaca,mohair,cashmere,vicuna,guanaco,rabbit and qiviut.

Wool.Wool fibers grows from the skin of sheep.It is composed of a protein known as keratin.Wool is relatively coarse fiber.It is crimpy (wavy) and has scales on its surface.Depending upon the breed of sheep,the appearence of the wool varies with some having a great deal of crimp and smaller,finer scales to those having little crimp and coarser scales. The thicker,,coarser,less-warm fibers have fewer and rougher scales.The better fibers with more crimp and finer scales are duller in appearance than the poorer quality wool fibers with fewer scales.

Underneath the scales is the main fiber body consisting of intermediate cells that hold the color pigment.These cells provide the fiber's strength and elasticity.In the center of the fiber is the medulla,which consists of spiral-shaped,air-filled cells.Some wool fibers that have no cortical(outer)layer are compensated with a larger proportion of medullary cells.This fact lessens the affinity for dyes,because the medulla has more fat than has the rest of the fiber.The finer wools,having no medulla,absorb dyes more readily.

Silk.Silk fiber is a fine continuously strand unwound from the cocoon of a moth caterpillar known as the silkworm.While silkworms are generally cultivated,another type,wild ( or tussah) silk,is obtained from uncultivated silkworm cocoons.The letter produces a coarser fiber.Silk is essentially composed of protein.

Silk fiber is relatively lustrous,smooth,lightweight,strong,and elastic.Historically,it has always been a highly desired fiber which has been used for apparel,home furnishings and upholstery.Its desirability is one of the factors that prompted the production of manmade fibers to simulate silk.

Mineral Fibers

Asbestos.Asbestos is a natural fiber obtained from varities of rock.It is a fibrous from of silicate of magnesium and calcium,containing iron,aluminium and other minerals.Asbestos is a acidproof,rustproof and flameproof.Consequently,it has been used for materials requiring certain of these characteristics.However,asbestos fiber particles that ludge in the lungs have been found to be carcinogenous and its use has therefore been restricted.