By: K. A. Vijay Kumar and M.K. Vittopa
The South India Textile Research Association, Coimbatore - 641 014



Introduction

Coir is natural vegetable hard fibre, extracted from the exocarp of the fruit of Coconut palm, Cocos nucifera (Linn). These fibres are widely cultivated in the tropics, particularly in India, Srilanka, Malaysia, Indonesia and Philippines. However India and srilanka are the main producers of Coir in the world1.

Coir fibres are largely used in the manufacture of Yarn, Cordage and wide range of furnishings such as mats, mattings, rugs, carpets, cushioning, insulation and packaging materials. The physical characteristics and chemical compositions2 of coir fibre are provided in table 1 and table 2 respectively.



Due to the presence of high quantity of lignin, coir fibre is very hard. Because of the relatively lower Length/Breadth ratio*, spinning of coir fibres is rather difficult. Hence, softening of coir fibres is necessary to enhance their spinnability. Some research studies were conducted earlier to improve the softness of coir fibres. Padmanabhan C.V.3 had tried with oil and water, Bhat J.V. et.al4 had used micro organisms and Prabu G.N.5 had used some organic & inorganic chemicals, to improve the flexibility of coir fibres. In all these techniques flexibility of coir fibres has improved to some extent, but the improvement was not found sufficient to enhance the spinnability of coir fibres substantially.

Earlier, SITRA has conducted extensive trials on softening of pineapple leaf fibres (PALF) towards enhancing its spinnability6. Studies were also carried out to improve the spinning quality of jute by the action of enzymes and other bio-agents7.

Hence, the present study has been conducted to achieve substantial reduction in the rigidity of coir fibres through appropriate softening which is essential for coir spinning.

* L/B ratio of cotton : 1300

L/B ratio of Pine Apple Leaf Fibres : 450

Softening of Coir Fibres

Physical and Chemical Impurities present in Coir Fibres

Mechanically extracted & retted coir fibres were tested for the Length Distribution and presence of physical and chemical impurities using Analytical Methods9,10. The results are given in Table 3.