Fibres, Yarns and Fabrics
This domain examines fibre classification, yarn structure and fabric construction. The exam tests how fibre origin and yarn and fabric structure produce properties such as strength, absorbency, shrinkage, drape and care needs.
Fibre classification
Natural fibres are vegetable (cotton, linen, jute), animal (wool, silk) or mineral. Man-made fibres are regenerated (viscose, modal) or synthetic (polyester, nylon, acrylic). Staple fibres are short; filament fibres are continuous. Cotton is absorbent and breathable but creases and shrinks. Polyester is strong and quick-drying but less absorbent. Silk is lustrous and strong with poor resistance to sunlight and perspiration.
Yarn structure
Yarn is made by spinning staple fibres or twisting filaments. Twist direction is S or Z; higher twist gives a stronger, harder yarn, lower twist gives softness. Blends combine properties, for example polyester-cotton gives strength with absorbency.
Fabric construction
Woven fabrics use warp and weft; basic weaves are plain, twill and satin. Knitted fabrics use interlooping and stretch more. Non-woven fabrics are bonded fibres. Fabric weight is expressed as GSM. Thread count, ends per inch and picks per inch describe woven density.
Worked example
A kurta must be cool in humid Assam weather and hold colour after washing. Cotton provides absorbency and comfort, but pure cotton shrinks. A cotton-viscose blend improves drape, and pre-shrunk or compacted cotton reduces shrinkage. Reasoning: fibre choice follows climate and care requirements, not appearance alone.
Traps
Calling viscose synthetic (it is regenerated). Confusing staple with filament. Assuming silk is the strongest fibre in all conditions. Forgetting that knit stretches and needs different handling from woven fabric.
Key points
- Fibres are natural or man-made, staple or filament.
- Plain, twill and satin are basic woven structures.
- Knits stretch because of interlooping.
- GSM measures fabric weight per unit area.
- Blends are chosen to balance cost, comfort and durability.