Section A: Yarns

Types of yarns:

All fibres need to be made into yarns before they are knitted/woven. Yarns are essentially long, continous strands made up of fibres twisted together.

Continous filament yarns: lightly twisting filament fibres together.

Staple yarns: short, staple fibres; they have to be carded/combed so the fibres lie in the same direction.

Blending:  modern fabrics contain more that 1 fibre. Blending is achieved by spinning 2 or more fibres together. To make a successful blend, the fibres MUST be the same length.

Reasons for blending: 

• reduce costs
• different effects
• stronger
• easier to care for.

Popular blends: 

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  • poly-cotton; cancels out shrinkage; creasing and slow-drying. Also makes the fabric more absorbant. However it is dangerous when set alight. 

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  • wool and nylon; softer, warmer, improves strength and resistance to abrasion, makes fabric lighter, prevents shrinkage + reduces costs!

Yarns and textures:

The characteristics of continous filament fibres can be changed by crimps, crinkles, snarls. The methods depend on the thermoplastic nature of the fibres.

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  • False…