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INTRODUCTIONConventional cotton is one of the most environmentally unfriendly crops grownanywhere in the world. Grown from a seed, cotton can be a sustainable andorganically grown crop. If all the cotton in the world were grown organically, the useof insecticides could be reduced by 25 percent! Cotton remains the most miraculousfiber under the sun, even after 8, years. o other fiber comes close to duplicatingallof the desirable characteristics combined in cotton.

"he fiber of a thousand faces and almost as many uses, cotton is noted for itsversatility, appearance, performance and above all, its natural comfort. #rom all typesof apparel, including astronauts$ in%flight space suits, to sheets and towels, and

tarpaulins and tents, cotton in today$s fast%moving world is still nature$s wonder fiber.It provides thousands of useful products and supports millions of &obs as it movesfrom field to fabric .

Properties of Cotton Fibres :Length of cotton ber:

Physically t he individual cotton bres c onsist of a single long tubular cell. Itslength is about 1200-1500 times t han its breadth. Length of cotton bre variesfrom 16mm to 52 mm depending upon the type of cotton.Indian cotton- 16-25 mmAmerican cotton- 20-30 mmSea Island- 38-52 mmEgyptian cotton- 30-38 mm

Fineness of cotton ber:

Longer the bre, ner the bre in case of cotton bre. It is e xpressed in term ofdecitex and it varies f rom 1.1 to2.3 decitex.Indian= 2.2-2.3dtexAmerican= 2.1-2.2 d texEgyptian= 1.2-1.8 dtexSea Island= 1.0-1.1 dtexFineness m ay b e more in case of immature bre. So it is n ecessary to expressmaturity with neness.

Strength and extension of cotton ber:Cotton bre is f airly a mong natural bres in relation to tenacity which is 3-

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3.5g/dtex. Its tensile strength is between wool and silk bre but disadvantageis l ow extension at break which is 5 -7%.

!astic properties of cotton:Recovery from deformation of cotton bre, yarn or fabric from applied load isvery low. By a pplying heat it cant be achieved. This p roperty c an be achievedby -1.Chemical treatment to improve crease recovery, but the problem is t hematerials b ecome harsher due to chemical treatment 2. blending or mixing ofcotton with elastic bre, e.g. polyester, blend ratio depends o n the end use ofthe fabric. The initial modulus is fairly high=05 g/dtex (wool=0.25 g/dtex)Cross"section:Cross-section of cotton bre is s ome what ribbon like. The cell wall is r ather

thin and the lumen occupies a bout two-third of the entire breadth and showsup very p rominent in polarized light. Fibre cross-section b ecomes r ound whenmercerized.#ppearance:Cotton bre is f airly s hort, ne and creamy w hite color. Color of the bredepends o n soil of growth. By a dding chemicals i n the soil, color of the cottonbre m ay be varied.Cri$p:

Cotton bre is m ore or less twisted on its l ongitudinal axis w hich cab not beseen from out side is c alled convolution. The twist in the bre does n ot to becontinuous in one direction i.e. if at rst right direction, then left direction. Thisproperty o f cotton fbre h elps i n spinning.