Raw materials used in Textile Industries

Introduction

Raw material (RM) is the primary substance which is used as an input to a production process for subsequent modification and finally modified into a finished good. Raw materials may be in processed or unprocessed state. Most of the times raw materials are natural resources such as cotton, oil, rubber etc. They are also altered to be used in different processes before being used in the final manufacturing process. So we can say that, the processed or unprocessed materials which are used to produce final textile products are called TRM.

Types of TRM

TRM may be of different types as follows –

• Fibre
• Yarn
• Fabric
• Dyes
• Chemicals and Auxiliaries

Fibre

The textile industries use different types of fibres which are derived from nature or manually produced. These fibres are used to produce dresses, towels, blankets etc. Some of these fibres were known and used in the earlier years of civilization, as well as in modern times. Other fibres have acquired varied degrees of importance in recent years. The factors influencing the development and utilization of all these fibres include their ability to be spun, their availability in sufficient quantity, the cost or economy of production, and the desirability of their properties to consumers.

Classification

Type	Name of Fibre	Source or Composition
Vegetable	Cotton	Cotton ball (Cellulose)
	Linen	Flax stalk (Cellulose)
	Jute	Jute stalk (Cellulose)
	Hemp	Hemp or abaca stalk (Cellulose)
	Sisal	Agave leaf (Cellulose)
	Kapok	Kapok tree (Cellulose)
	Ramie	China grass (Cellulose)
	Coir	Coconut husk (Cellulose)
	Pina	Pineapple leaf (Cellulose)
Animal	Wool	Sheep (Protein)
	Silk	Silkworms (Protein)
	Hair	Hair bearing animals (Protein)
Mieral	Asbestos	Varieties of rocks (silicate of magnesium and calcium)
Cellulosic	Rayon	Cotton linters or wood
	Acetate	Cotton linters or wood
	Triacetate	Cotton linters or wood
Noncellulosic Polymers	Nylon	Aliphatic polyamide
	Aramid	Aromatic polyamide
	Polyester	Dihydric alcohol and terephthallic acid
	Acrylic	Acrylonitrile (at least 85%)
	Modacrylic	Acrylonitrile (35% - 84%)
	Spandex	Polyurethane (at least 85%)
	Olefin	Ethylene or propylene (at least 85%)
	Vinyon	Vinyl chloride (at least 85%)
	Saran	Vinylidene chloride (at least 80%)
	Novoloid	Phenol based novalac
	Polycarbonate	Carbonic acid (polyester derivative)
	Polybenzimidazole	Tetraminobiphenyl and diphenyl isophthalate
	Alginate	Calcium alginate
	Fluorocarbon	Tetrafluoroethylene
	Graft	Molecular graft of polymers
	Matrix	Mixture of polymers
	Anidex	Monohydric alcohol and acrylic acid
	Lastrile	Acrylonitrile ((10-50%) and a diene
	Nytril	Vinlylidene dinitrile (at least 85%)
	Vinal	Vinyl alcohol (at least 50%)
Protein	Azlon	Corn, soybean
Rubber	Rubber	Natural or synthetic rubber
Metallic	Metal	Aluminum, silver, gold, stainless steel
Metal	Glass	Silica sand, limestone
	Ceramic	Alumina, silica

Yarn

Yarns can be made of staple fibres by several techniques. The method used is dependent upon such factors as the economic implications, the fibres to be used and desired properties of the yarn to be produced. Rings pinning is the oldest and most wide spread technique. Open end spinning is another major method. The development of short fibres, or staple, into yarn, when started in terms of basic manufacturing processes, is as follows:

Carding

↓

Combing

↓

Drafting

↓

Twisting

↓

Winding

As the fibres pass through these processes, they are successively formed into lap, sliver, roving and finally yarn. Here the manufacturing operation in which these stages occur:

• Lap to card sliver by the carding process
• Card sliver to comb sliver by the combing process (if the fibre is to be combed)
• Sliver to roving by the drafting, or drawing process
• Yarn reeled on bobbins, spools or cones by the winding process

Fabric

Fabric is a planar textile structure produces by interlacing yarns or filaments. Most fabrics are produced through knitting or weaving, but some are produced by non-woven processes such as braiding, felting, and twisting.

Weaving

A major method of fabric construction is weaving. The technique probably became known before spinning. Primitive people may have observed the interlaced grasses and twigs in the nests of birds, and thus discovered how they could make clothing for themselves. Spinning developed when people discovered that the raw materials could be improved before they were woven. In course of time, rude looms were made, which were crudely simple and hand-operated. The modern power loom used in the textile industry today essentially performs the same operations as the simple hand operated loom.

Knitting

Knitting is the second most frequently used method of fabric construction. The popularity of knitting has grown tremendously within recent years because of the increased versatility of techniques, the adaptability of the many new man-made fibres, and the growth in consumer demand for wrinkle resistant, stretchable, snug-fitting fabrics, particularly in the greatly expanding areas of sportswear and other casual wearing apparel. Today, the usage of knitted fabrics ranges from hosiery, underwear, sweaters, slacks, suits and coats, to rugs and other home furnishings.

Some commercial names of fabric are as follows:

• Aertex
• Angora
• Braid
• Brocade
• Chiffon
• Canvas
• Chambray
• Denim
• Fleece
• Hopsack

Dyes

The dye is a complex compound which is applied in the textile materials represent color and contains chromophore and auxochrome groups in its chemical structure. It is necessary to know which dyes have an affinity for the vegetable, animal, or man-made fibres to select the proper dye for a fibre.

Different types of dyes are used in the textile industries as raw materials are as follows –

• Basic dyes
• Acid dyes
• Mordant dyes
• Substantive direct dyes
• Developed dyes
• Azoic dyes
• Disperse dyes
• Vat dyes
• Reactive dyes
• Pigment dyes

Chemicals and Auxiliaries

Dyeing chemicals and auxiliaries enables a processing operation in preparation, dyeing, printing or finishing to be carried out more effectively, or which is essential if a given effect is to be obtained.

Different types of chemicals and auxiliaries used in dyeing, printing and finishing are as follows –

• Whitening agent
• Wetting agent
• Fixing agent
• Detergent
• Silicon
• Stiffering agent
• Water proofing agent
• De-foaming agent
• Enzymes
• Caustic soda
• Soda ash
• Acetic acid
• Oxalic acid