Thursday, December 26, 2013

CLASSIFICATION OF TEXTILE FIBRES

There are various systems of classifying textile fibres. The simplest way of classifying textile fibres are on the basis of natural fibres and manufactured fibres.

1. Natural Fibres: Natural fibres may be divided into three categories; animal, vegetable and mineral.

a. Naturally occurring fibres of vegetable origin

The chief vegetable fibre is cotton, indeed it is the main textile material. Cotton is a seed-hair and consists of a single cell. Other vegetable fibres are flax, hemp, jute and ramie, which are best fibres. Best fibres are obtained from the inner barks of the stems of the plants.

b. Naturally occurring fibres of animal origin.

Wool and silk are the chief animal fibres. In addition to animal hairs form sheep, other animal fibres are obtained from goats, namely, mohair from Angora goat and cashmere from Cashmere goat, other are camel-hair, bear hair, horse-hair etc.
Cultivated silk is 2nd in importance to wool among the animal fibres and may be regarded as the aristocrat of textiles (queen of fibres). Silk is produced from cocoon.

c. Mineral fibres are of natural in category.

These are entirely inorganic in nature. The chief mineral fibre is asbestos, which has little textile merit but is famous on account of its resistance to heat; similarly glass and metal fibres have no textile merit. 

2. Manufactured fibres: Manufactured fibres may be divided into two main categories, regenerated and synthetic.

a. Regenerated man-made fibres which use some naturally occurring substance as the raw material.

Regenerated fibres may be classified according to the nature of parent material, cellulose or protein, and the commonest is viscose rayon prepared from cellulose in the form of wood pulp. Another type is regenerated from a solution of cellulose in cuprammonium hydrate e.g. Bamberg rayon. Artificial silk can be regenerated with casein as the raw material. For casein fibres raw material is obtained form skimmed milk. Casein-fibres do not possess elasticity, its dry strength is moderate and wet strength poor; so its use is limited. Cellulose derivative e.g. cellulose nitrate, cellulose acetate are also regenerated and fall in this group but no commercial importance.


b. Synthetic man-made fibres which use some artificially prepared organic compound as the initial raw material.

Synthetic fibres are prepared synthetically from artificially prepared organic compounds as the initial raw material. Synthetic fibres do not require raw material of high molecular weight as their starting point but may be built up or synthesized from the simple atoms. Pe-Ce was the 1st synthetic fibre but nylon is the most famous. Other examples are Polyester, Dacron, Tetron, Terylene etc.

So classification may be:
a. Natural cellulose fibres e.g. cotton, flax, jute etc.
b. Natural protein fibres e.g. wool and silk.
c. Regenerated cellulose fibres or rayons, including cellulose derivatives.
d. Regenerated protein fibres e.g. casein fibre.
e. Synthetic fibres e.g. nylon, Perlon, Terylene, Orlon etc.
f. Mineral fibres e.g. asbestos.

Another system of classification:
1. Cellulose fibres, native and regenerated.
2. Protein fibres, native and regenerated.
3. Synthetic fibres
4. Mineral fibres

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