FIBRES FOR ACTIVE SPORTSWEAR:
Developments in synthetic fibres which are tailor-made have opened up enormous avenues for their use in sportswear to meet specific requirements. In active sportswear single fibre is seldom used. Mostly, speciality fibres are used in conjunction with normal fibres. Examples of such fibres are given below:

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Hygra: Unitika Limited has launched Hygra, which is a sheath­-core type filament yarn (Fig 1) composed of fibre made from water ­absorbing polymer and nylon'°. The water-absorbing polymer has a special, network structure that absorbs 35 times its own weight of water and offers quick releasing properties that the conventional water-absorbing polymer cannot do. On the other hand, nylon in the core gives tensile strength and dimen­sional stability.' Hygra also has superior antistatic properties even under low wet conditions. The main apparel applications include sports­wear like athletic wear, skiwear, golf wear etc.

*            Lumiace: Lumiace is also a product from Unitika. It is a collec­tion of polyester filaments having different fineness (0.5 - 2.0 denier per filament) and irregular cross sections. Hygra - Lumiace combination in knitted fabric is very popular in top Japanese athletes.
*        Dryarn: Dryarn is the new fibre from Aquafil. It is a completely recyclable polypropylene microfibre. Fabric from Dryarn is very lightweight and comfortable and used in different sports. In addition it has a soft handle and a high thermo­regulatory capacity and also dries quickly. Bacteria cannot settle on smooth surface of the fibre which avoids unpleasant odour associated with decomposition of bacteria.
*            Killat N: Killat N from Kanebo Ltd is a nylon hollow filament. The hollow portion is about 33 per cent of the cross section of each filament due to which it gives 


good water absorbency and warmth retentive property. The manufacturing techno­logy of Killat N is very interesting. The yarn is spun as bi-component filament yarn with soluble polyester copoly­mer as the core portion and nylon as the skin portion. Then by giving alkali weight loss treatment the soluble polyester copolymer of the bi-component filament will dissolve and a large hollow portion (exceeding 30 per cent of the cross section) will be created.

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Triactor: Toyobo Co Ltd has developed Triactor, which is a perspiration absorbing/quick drying polyester filament. Polyester is hydrophobic and does not absorb moisture but by changing the fila­ments to Y shaped cross section Toyobo has realized quick perspira­tion absorbency by capillary action the hydrophobic nature and large filament surface of polyester filaments realize quick drying and refreshing properties at the same time.

There are many other fibres, which have good sweat absorption and fast drying property. Most of them are either nylon or polyester.
CoolMAX: It is a tetra-channel polyester fibre with a cross section like a double scallop. It has improved wicking capability and moisture vapour permeability.


FIBRE BLEND: Knitted fabrics made from polyester/wool blends or polypropylene /wool blends can improve wicking and insulation properties within a single layer fabric structure.
CORTERRA: Corterra is a PTT (polytrimethyleneterephthalate) used for sportswear as stretch, softness, comfort, performance, drape, durability and permanent strain-resistance.
NATURE WORKS: Independent evaluation of Nature Works PLA (polyactide) fibres made from corn, by the reputable Hohenstein Research Institute, Germany, demonstrated that Nature Works fibres offered better wear comfort in a two-layer fabric than PES, according to Mr. Dartee, Cargill Dow, Holland. The inside layer consisted of Nature Works or PES and the outside layer of cotton, as a liquid sweat buffer. The combination of superior hand, drape, strong wicking performance, and resilience and UV stability makes Nature Works PLA an attractive candidate for active-wear end uses.