Yarn: Long continuous strands made up of fibres twisted together.
Fibres must be spun into yarns before weaving or knitting into fabrics.
Staple yarns - short, staple fibres are carded (combed) so they lie in the same direction, before twisting together. Staple yarns = hairy, good at trapping air between fibres - good insulators.
Filament fibres can be blended with staple fibres, but filaments need cutting into short staple fibres before spinning. Fibres must be same length for successful blend.
Continuous filament yarns = smooth, not good at trapping air - fabrics are not good insulators. Blending continuous filaments results in multi-filament yarn, e.g. polyester and nylon.
Plied yarn: single yarns twisted together. 2 ply=2 yarns, 3 ply=3 yarns etc.
Tex/dernier: measure of the weight of a yarn - indicates how densely spun it is. (Think tights)
spinning 2 or more types of fibres together to make a blended yarn - it enables fabrics to be made which are better suited to the product.
Reasons for blending
- Reduces cost of fabric
- Gives different effects in texture and handle of fabric
- Allow for novelty effects when dyed
- Makes fabric with specific properties for a particular end use.
- To make fabric stronger
- To make fabric easier to care for
- Enable crease resistance
- Allow for heat setting (e.g. setting pleats of a skirt in place)
Yarns can be…