Dr. A.N. Desai, Director, BTRA
Cotton versus Man-made fibres
Cotton, inspite of severe competition from manmade fibres continues to hold its position in the textile industry world wide accounting around 45% of fibres used ; in India 60% of fibre used by the industry is cotton. While cotton has many desirable characteristics like good moisture absorption ,wicking and cotton fabrics are breathable , the fibre suffers from some disadvantages as well ; for instance poor wrinkle recovery and does not have easy care properties like synthetics. Plasma technology can be used for durable finish of cotton using non-hazardous chemicals . Another research area in this durable finish foe wrinkle recovery is iconic crosslinking. These technologies are clean and eco-friendly and need to be explored.Thus competitiveness of cotton is also related to technology change and diversified end uses. Creating new markets for cotton or introducing cotton in existing products is an area that needs to be looked into. In industrial or technical textiles use of cotton needs non traditional technologies.
Cotton in personal care sector in uses like wipes , feminine hygiene products is a valuable raw material since it is comfortable for next to skin applications . Its superior wet strength enhances its tear strength in tough applications like domestic wipes. Product development like Hi-DriTM – hydrophobic purified cotton for use in hygiene or medical products while keeping fabric and skin dry is desired. Propensity of cotton to absorb moisture can often be a negative in some applications. Development of moisture management technology for cotton where consumers can enjoy fast drying and moisture wicking performance seen in synthetics but coupled with comfort and softness of cotton is highly desirable. Only two fibres are of commercial significance in this regards in products designed to pick up liquids and to wipe surface dry – cotton and cellulose pulp. Cotton is exceptionally suitable for both single use or long term use wipes .Some patented products of these types are Tran Dry ®which allows fabric to work and spread perspiration as well as or better than synthetics which helps in a T-shirt with wicking and fast drying performance . Another patented technology is Wicking Window eliminates feeling of wet, saturated fabric against the body . The technology forces the transfer of moisture away from skin to outside of fabrics when it can evaporate, keeping the wearer drier and comfortable , say during an exercise. Self cleaning cotton fabric development is another area that needs attention.
Galloping innovation
Many conventional water repellent treatments inhibit fabric breathability and transfer of moisture . STORM Cotton TM and STORM Denim TM are examples of durable highly water repellent finish at same time breathable. Technologies like Plasma application – a clean and green technology with minimum water usage – can be applied by many finishes in eco-friendly ways – wrinkle recovery, breathable but water repellent , fabrics including denims and many multifunctional finishes like a fabric having at the same time properties such as fire retardant , antibacterial and UV protective.
In the area of protective textiles in applications where heat stress influences productivity – in chemical protective clothing ,reports indicate cotton non-woven treated to enhance water repellency performed better than synthetics. Cotton needle punched nonwovens are reported to be a very feasible idea for accoqusticinsulation. In industrial filters, filtration performance of fibres depends on physical ,mechanical and chemical properties as well as on fibre morphology and stress – strain response to filtration environment. Cotton ranks high in filtration efficiency of both liquid and gas in those environment which are compatible with cellulose.
Steps to promote cotton consumption
India being the 2nd largest producer of cotton needs to look beyond the conventional yarn and fabric production techniques. Research efforts for product / process development is imperative for new outlets for cotton usage, improved finishes for current products and technology development to replace or attain the properties of synthetics . Use of cotton in technical textiles and nonwovens is negligible in India. With nonwoven industry picking up in India , hydro entanglement and thermal bonding to cotton nonwovens need to be promoted to developnew products and replace some of the synthetic products. Research efforts on the lines of Cotton Incorporated in the USA are necessary to promote use of cotton and protect the interests of cotton growers, cotton trade and other stakeholders of cotton economy . Perhaps a Centre of excellence to promote cotton or allot different areas of post harvest cotton technology to different research institution is worth exploring.