Fiber after treatment.

The production of fabric from fiber involves various intermediate steps between spinning and weaving.
They must be scoured, lubricated, sized, dyed and may undergo various treatments.

Scouring.

The removal of impurities from textile materials is called scouring. This is done by surface active agents such as soap and synthetic detergents. On the surface of fibres oils,fats etc are present naturally or purposely added during various process. The principle function of this process is removing these impurities.

Lubrication.

In order to reduce friction against themselves and against the processing machinery, lubrication is done. The lubricants are generally mineral or vegetable oil or suitably refined petroleum products.

Sizing.

Size is surface coating in order to protect the yarn during weaving. It makes the yarn smooth by binding the protruding fibres onto the core of yarn. Starch is used to size cotton and to some extend wool and rayon.

Protruding fibers.

Dyeing.

Dyeing is fixing the dye (colorant) to the substrate. Dye is distinct from pigment because it is soluble in water and it possess attractiveness for their substrate, these two properties are not possess by pigments. Natural cellulosics and protein fibers are well known dye. The synthetic fibres are often very difficult to dye.

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