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PLANT AND SOCIETY. ESTELLE LEVETIN & KAREN MCMAHON Chapter 18. CLOTH MAKING. Plant fibers Fibers used to wave cloths-Textile fibres Cordage fibers Filling fibres Animal fibres (wool, silk) protein Plant fibres cellulose. Surface fibres on covering of seed, leaves or fruits

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Chapter 18


  • Plant fibers

  • Fibers used to wave cloths-Textile fibres

  • Cordage fibers

  • Filling fibres

  • Animal fibres (wool, silk) protein

  • Plant fibres cellulose

  • Surface fibres on covering of seed, leaves or fruits

  • Linen are soft fibres or bast fibres (dicot trees)

  • Hard fibre from vascular bundles in veins (both xylem and phloem)

  • Monocot leaves source of hard fibres (Manila Hemp)

  • Hard fibres have high lignin than soft fibres

Extracting Fibres

  • Fibres separated from source material through Ginning

  • Soft fibres extracted from stem through Retting

  • Degradation of soft tissues through microbial action, leaving tough fibres strand intact and freed

  • Decortication-Unwanted tissues scraped away by hand or machine for hard fibres

Spinning into yarn

  • Fibres freed from source then cleaned

  • Fibres are combined and laid parallel to each other to form a strand

  • Strand stretched or pulled with fingers and individual strands are twisted together to form thread

  • Spindle made spinning easier

  • Rotation of spindle that twists and holds the fibres together forming a yarn


  • Arab introduced cotton to Muslim Spain

  • Qutn

  • Top cotton producing country China

  • United States, India, Pakistan, Egypt, Brazil


  • Most popular natural fiber accounting for half of world’s textiles

  • Cloth made from seed fibres from Gossypium sp.

  • Malvaceae

  • 20-30 species in genus Gossypium native to parts of Asia, Africa and Central America

  • Cotton is shrubby plant with palmately lobed leaves

  • Most species perennial

  • Grows best in warm climate

  • Flower color from white to purple

  • Fruit is capsule (commercially called ball) when open splits along five seams, revealing white mass of fibres

  • In cotton plant, fibres are hairs that extend extending from seed coat of each of 10 or so seeds in every fruit

  • 20,000 seed hairs may grow from single seed

  • Each cottonseed hair (actually a single seed coat cell) is twisted, hollow strand of cellulose upto 7.62cm (3 inches) in length and flattens at maturity

  • Seed hairs may be

  • Lint or staples (long, slender fibres)

  • Linters (shorter, fuzzy hairs)

  • High quality cotton from longest of lint

  • Purity of cotton cellulose (90 %) and natural twist make cotton excellent fibre for spinning into yarn

SEM Cotton fibers

Cotton Gin

  • Cotton balls mature 50-80 days after fertilization

  • Defoliants sprayed, leaving only bolls for picking

  • Machine process

  • Harvested bolls or fibres sent to a gin

  • During ginning lint is removed from seed

Old and New Varieties of cotton

  • Commercially new important sp. are G. hirsutum and G. barbadense

  • G. arboreum and G. herbaceum old varieties

Operation of Cotton Gin

  • Saw gin a roller studded with spikes covered by metal mesh

  • Spikes draw in lint but seeds do not pass through mesh and left behind

  • Whitney’s Gin separates cotton fibers from seed much quickly

  • Whitney’s Gin produce 50 pounds (22.5kg) of cotton fibres per day

  • Cotton seeds source of cottonseed oil

  • Ginning fibres packed into large bales

    and graded for quality

  • Graded bales shipped to yarn or cloth manufacturers

  • Lint is straightened, sorted into parallel bundles of similar size in preparation for spinning into yarn

Finishing and Sizing

  • May alter the appearance and modify function of textile

  • Plant fibres bleached to remove natural color

  • Bleaching may involve soaking into sour milk or cow’s dung

  • A bath in buttermilk followed

  • After washing cloth spread on grass until exposure to sun bleached it white

  • Macerization, finishing process improves strength, luster and affinity for dyes

  • Cotton macerization involves passing cotton through caustic soda (NaOH)

  • Permanent press involves shape-retentive finish

  • Cellulose fibres like cotton wrinkle and crush easily

  • Chemicals applied that cross-link cellulose fibres giving built-in-memory , shape of garment retained even after laundering, ironing

Bio-engineered Cotton

  • Bollgard trade name for transgenic cotton

  • Incorporation of toxin producing genes from Bacillus thurigiensis

  • Bt toxin effective insecticide against three

    particularly noxious pest of cotton-cotton bollworm , pink bollworm, tobacco budworm

  • Agracetus-biotech company

  • Working on transgenic cotton plants that combine breathability and feel of cotton cloth with low-maintenance and heat-retaining properties of polyester

  • Created transgenic cotton plant that fill the hollow middle of cellulose seed hairs with small amount of polyester material

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