India is a major producer, consumer and exporter of 100% cotton yarns as well as blended yarns. The major types of blended yarns exported from India are polyester/cotton and polyester/viscose yarns. The blended fabric market has grown at a CAGR of 10.1 % during 2006-13. The share of blended fabrics in the year 2012-13 is around 15% out of total fabric production. The market trend shows that the cotton yarn demand growth is expected to slow down to 5.1 percent annually between 2009-10 and 2014-15, as compared to 6.2 per cent CAGR recorded in the previous 5 years. At the same time, it is expected that the demand for blend yarn will outpace the demand for cotton yarn in near future. Presently poly/cotton and poly/viscose are the major yarn types exported from India. Other major blend yarn types exported are cotton/viscose, acrylic/cotton, poly/acrylic, poly/wool etc. Most of the blended yarns produced are binary yarns (two component yarns). Tertiary yarns are also produced to some extent. Figure 1 shows the production figures of spun yarns in the last 5 years for 100% cotton yarns, blended yarns and 100% Non cotton yarns. It can be seen that though 100% cotton yarns dominate the spun yarn market, the production of blended yarns are on the rise. The Compound Annual Growth Rate (CAGR) of blended yarns during 2006-13 is 4.3 %.

Some of the major blended yarn types produced by Indian spinning industry along with their end-use applications are given in Table 1.

 

Table 1: Major types of blended yarns

Sl.No.

Blends

End uses

Contribution of fibres to end use

1

Poly/cotton

Shirtings, suitings, uniforms, dresses, casual wear etc.

Polyester contributes to durability and wrinkle resistance.

Cotton contributes to comfort.

2

Poly/viscose

Uniforms, Suitings, Pants, skirts etc.

Polyester contributes to resiliency shape retention, improves wet strength.

Viscose contributes to absorbency and texture.

3

Cotton/viscose

Dresses, suits, sportswear, Sarees, men's shirts etc.

Cotton contributes to comfort.

Viscose gives lustre & softness to blend.

4

Acrylic/cotton

Sweaters

Acrylic contributes to softness, warmthness and durability.

Cotton contributes to comfort.

5

Poly/acrylic

Overcoats, blankets etc.

Polyester contributes to strength.

Acrylic contributes to soft handle and warmth.

6

Poly/wool

Suitings

Polyester for shape retention, to reduce cost of blended fabric.

Wool provides warmth, resiliency, drapability.

Cotton blended yarns


Cotton and Polyester


Polyester in blend with cotton is the most popular blend in the market. Fabrics of various blend ratios are available in the market today. A blend of 65% polyester and 35% cotton is common. Other blend ratios are 67/33, 70/30, 50/50, 45/55, 52/48, 80/20 of polyester and cotton respectively. A blend of 65/35 polyester and cotton produces a fabric much suitable for daily wear. With P/C blend, the excellent crease resistance, shape retention, easy care, and durability of polyester combine with the good absorbency and heat conduction of cotton. In various proportions, this mix of fibres offers superior practical performance over cotton alone. The 'cotton-rich' blends (that is, more than 50% cotton in the blend) offer more of the characteristics of cotton. P/C blends are used in a variety of shirts, slacks, dresses, blouses, sportswear and many home textile items.


Cotton and Viscose


Cotton/Viscose blended fabric has superior comfort, enhanced lustre, higher uniformity and softer feel. Poor wet modulus of viscose is compensated by blending with cotton. Cotton and viscose fibre are generally blended in proportions of 55/45, 65/35 70/30, and 85/15. They are being used for making towels, shirting, denim, trousers, knitwear, sarees, dhoties and home linens.


Cotton and Acrylic


In a cotton/acrylic blend, acrylic contributes to softness, warmthness and durability whereas cotton contributes to comfort. Such blend offers more comfortable, warm, and yet light garment. The general blend proportions are cotton/acrylic 75/25, 60/40 and 50/50.


Cotton blends with other fibres


Cotton is blended with many natural, semi-synthetic and synthetic fibres to produce products for desired end use. Wool contributes to warmth, absorbency, body, drape, and hand to a cotton/wool blend. Silk contributes to sheen, drape and light weight to cotton/silk blend. Nylon adds strength, smoothness, silkiness and wrinkle resistance in a cotton/nylon blend. Spandex (5 to 30%) provides good elasticity in a cotton/spandex blend. Additions of Kevlar fibres to cotton enhance the tensile and tear strength of cotton fabrics. Polypropylene blends with cotton reduces yarn cost, improves bulk and strength of yarn whereas blending very small quantities (5-10%) of X-static (silver fibre) provides anti-static and anti-microbial properties to cotton blend yarn.


Cotton blended yarns in technical textile applications


In India, the production of different technical textile items has been steadily increasing. As per the baseline survey of technical textile industry in India, the Indian technical textile industry has grown at an annual rate of 11% to reach an estimated market size of Rs. 70,151 Crore in 2012-13 from Rs. 41,756 Crore in 2007-08. Cotton in blend with polyester has numerous applications in technical textile segment. Poly/cotton blends are used in making sewing threads, filter cloths, sports garments, surgical gowns & drapes, bed sheets, conveyor belts, seat covers etc. In most of the applications, P/C of 50/50 and 65/35 are the common blend proportions used for producing products.


Works @ CIRCOT on Blends


The Central Institute for Research on Cotton Technology (CIRCOT) has undertaken various studies on development and production of blended textiles, particularly with cotton as a major component in the blend. Speciality fibres such as hollow polyester fibres, trilobal fibres, micro-denier fibres etc. were blended with cotton to produce textiles with different functional properties.


CIRCOT has also developed methods for blending cotton with short wool as well as speciality animal fibres such as Angora rabbit hair. A processing technology in the cotton system for blending cotton with ramie fibres has also been developed. Tropical rich feel suiting and jackets from cotton/wool blends and knitted garments from cotton/ramie blends were produced. Table 2 summarises the past works done at CIRCOT on cotton blends.


Table 2: Work done at CIRCOT on cotton blends

Sl. No.

Study

Description

Year

1

Blends of Indian cotton with polyester fibres

Sujata, Suvin, PSH, Hybrid 4, Varalaxmi varieties were blended with polyester to spin 50s and 80s count yarns

1974

2

Cotton-jute blend

Jute caddies blended with short staple cotton and Jute staple fibre with long staple cotton.

1977

3

Cotton-pineapple fibre blend

Cotton-pineapple fibre blend attempted

1987

4

Cotton with specialty polyester fibres

Specialty fibres like hollow polyester, trilobal, microdenier fibres were blended with cotton.

1990s

5

Cotton /ramie blend

Cotton/Ramie blend of 65/35 proportion was attempted and yarn counts upto 40s count was spun.

2007

6

Blending Indian short wool and Angora rabbit hair with cotton

16s & 20s yarn spun by blending wool with DCH 32 and J34 cottons.

30s yarn produced by blending Angora rabbit hair with Suvin and DCH32 cottons.

2007

Presently CIRCOT is working on "Cotton-rich blends" with fibres like PLA and bamboo viscose targeting end-use applications in sports and medical field. Binary and tertiary blends of cotton with other fibres are being produced. PLA fibre of length 38 mm and 1.3 D was blended with MCU-5 cotton of 31.5 mm length and 1.2 D fineness. PLA fibre was blended with combed cotton at the blowroom stage. A 40s Ne ring spun yarn was produced using different cotton/PLA blend ratios of 80/20, 65/35 and 50/50 with different twist levels using compact ring spinning technology. The produced yarns were knitted into plain fabrics and tested for moisture management and other performance related characteristics. Results show that Cotton-rich/PLA blend fabrics are excellent in terms of moisture management capacity and are suitable for sportswear. Further trials are currently in progress for improving the functionality of these fabrics.

 

Conclusion


Over the decades, share of manmade fibres has risen and that of natural fibres has fallen. However, the world fibre demand has continued to grow and natural fibre still account for almost one-third of the total. Cotton alone accounts for about 30% of world fibre demand and therefore continues to have a major effect on the world fibre market. Cotton is a major fibre in India and it still remains as a dominant fibre as far as the Indian textile industry is concerned. Cotton drives growth both in yarn and fabric production. Cotton fibre blends with polyester, viscose and acrylic have proven to be useful in various apparel and home textile applications. The blend yarn market is growing both in domestic and export sector.


The extent to which cotton fibres remain as a constituent in a fibre blend is a major challenge considering the recent introduction of regenerated cellulosic fibres like lyocell, modal, and bamboo viscose. As the availability of these fibres is unaffected by the vagaries of nature or by decisions of farming community, they pose a serious threat to cotton and other natural fibres. In the technical front, apart from regenerated cellulosics, new fibres like soybean protein fibre, PLA fibre provide specific functionalities to the end product. These fibres, in addition to regenerated cellulosics, can be blended with cotton in a "cotton-rich" blend to utilise their specific properties in the end product. Realising this need, CIRCOT has now undertaken a project on cotton-rich blends in which some of the new generation fibres are blended with cotton, targeting end uses in performance apparels, home textile, and medical applications.



The authors are associated with the Central Institute for Research on Cotton Technology, Matunga, Mumbai, India.