Textiles
The Textiles domain tests fibre classification, properties, yarn and fabric construction, and finishing. Expect questions that ask you to match a fibre to an end use and justify the choice on performance properties rather than brand names.
Fibre classification
- Natural: vegetable (cotton, linen, jute - cellulose), animal (wool, silk - protein), mineral (asbestos).
- Man-made: regenerated (viscose rayon, acetate from cellulose) and synthetic (polyester, nylon, acrylic from petrochemicals).
Key properties
Cotton: absorbent, air-permeable, strong when wet, low elasticity, creases. Linen: stronger, stiffer, quick-drying, creases badly. Wool: elastic, insulating, felts, harmed by hot water and agitation. Silk: lustrous, strong, but degrades in sunlight and perspiration. Polyester: hydrophobic, thermoplastic, oleophilic, durable, quick-drying.
Yarn and fabric
Spinning makes yarn; twist gives strength. Simple, ply and fancy yarns. Woven fabrics have lengthwise warp and crosswise weft; plain, twill and satin are the three basic weaves. Knitting is loop-based and stretchy; non-wovens are bonded.
Finishes
Mercerisation of cotton with sodium hydroxide increases lustre, strength and dye uptake. Sanforisation controls shrinkage. Calendering gives a smooth surface.
Worked example. Choose a fabric for Kerala summer school uniforms. Cotton: high absorbency and air permeability allow sweat evaporation; blends with polyester add crease resistance and durability but reduce comfort. Reason from properties, not preference.
Traps. Mercerisation applies to cotton, not silk; warp is lengthwise; and "silk is a plant fibre" is a classic error.