2A Cotton Flashcards
Natural polymers - plant (cellulosic)
Properties (cotton)
- absorbs up to 65% of its weight without dripping (moisture)
- non-static
- cool/breathable
- good strength/abrasion resistance/durability
- biodegradable
- machine wash/dries easily
- poor elasticity: creases badly/shrinks
- highly flammable
- once wet, can take a long time to dry, it may become uncomfortable and can be attacked by mildew
- stains easily (water-borne stains)
Aftercare (cotton)
- can be washed/ironed at high temps.
A typical untreated cotton fibre
- matte appearance
- soft drape
- smooth touch
- feels comfortable to wear
What is cotton made from?
The cellulose from the seed pod (boll) of the cotton plant, where it emerges from the ripe seed boll as a bundle of soft fibres
What is mercerised cotton?
Mercerisation: a treatment that changes the way cotton fibres look and feel, making cotton more lustrous and brighter in colour
What type of fibre is cotton?
A staple and cellulosic fibre
Production of cotton (8)
- harvested by hand/machine
- packed in loose bales
- arrives at a SPINNING MILL to be broken up (removal of seeds/leaves/twigs) via a GINNING machine, which pulls the cotton fibres off the seeds to separate the two - the separated fibres (LINT) have a staple length of 20-50mm
- CARDING machines open out the laps (fibres) using a COMBING mechanism, which are then collected in a ROPE-LIKE form (SLIVER)
- DRAWING: the slivers are passed through rollers to be made more uniform, making them more closely aligned and drawn out to reduce the thickness
- the fibres are then combed to remove short fibres (up to 25%)
- the fibres are then twisted slightly into a ROVING
- SPINNING: the roving is fed from the rollers and twisted as it is wound onto a bobbin (rotating at a high speed), further improving its strength
What conditions do cotton plants grow in?
- tropical climate
- wet soil
Consequences of toxic chemical usage from cotton production
Use of pesticides/dyes/bleach/finishes:
- pollutes waterways (eutrophication)
- kills ecosystems/habitats
- makes water too salty and polluted with chemicals (forms salt deserts)
- makes land barren/infertile (unable to grow crops)
- harms farmers (especially those in developing countries)
- birth defects and blood diseases in children (surrounding areas)
Other damages to the environment from cotton production
- large amounts of water consumption, only to achieve a small amount of cotton production (20,000L of water for 1kg of cotton)
- CO2 emissions from manufacture/distribution
- plastic waste from packaging
- non-biodegradable
Why should we use organic cotton instead?
- more environmentally friendly (use of natural pesticides in farming)
- farmer friendly (less health risks)
- sustainable (largely rain-fed and the soil is fertilised with organic material)
Fabrics (cotton)
- corduroy
- muslin
- denim
- broderie anglaise
- gingham
- seersucker
What is Peruvian Pima cotton?
- naturally coloured cotton (no artificial dyes)
- cotton that is grown organically (doesn’t require fertilisers/pesticides)
- cultivated by the Peruvians 1000s of years ago
Features of Peruvian Pima cotton
- requires little maintenance
- more resistance to insects
- uses less water
- principal colours: cream/beige/brown/chocolate/mauve
- quite dull
- good for jackets/trousers/muted collections (not as much variety in colour compared to non-organic cotton)
End-uses (cotton)
- clothing: e.g. shirts/dresses/underwear/socks
- tents
- towels
- threads
