

Spinning
System Produces Core-Wrapped Yarn in a Single StepBy Amy Spillman May 14, 2002Tandem spinning, a U.S.-patented
technology, produces soft, yet strong, bicomponent yarn more than 10 times
faster than conventional ring spinning systems allow. The tandem system, a
combination of two different spinning technologies, was developed by
Agricultural Research Service scientists
at the Southern Regional Research Center (SRRC) in New
Orleans, La. To improve the strength or performance of fabrics, many textile
manufacturers combine two fiber classes, such as cotton and polyester, into one
strand of yarn. Fabrics made from such yarn are called intimate blends.
Although stronger than 100 percent cotton, these intimate-blend fabrics
sometimes exhibit undesirable properties. For example, they frequently pill, or
make lint balls on their surface as they wear, and they do not provide the
comfort of a 100-percent-cotton surface. A few years ago, scientists at the SRRC developed new spinning technologies
to form bicomponent, or core-wrap, yarn in which the core material
is usually a strong, synthetic fiber and the wrap/sheath is 100 percent cotton.
The core contributes excellent mechanical and functional properties to the
yarn, such as wrinkle resistance, and the cotton wrap provides the desired
comfort characteristics. Fabric made from core-wrap yarn has added strength
because of the yarns synthetic core, yet it maintains the soft texture of
cotton. To increase the productivity of core-wrap spinning, SRRC scientists, led by
cotton technologist Paul Sawhney, successfully developed a tandem spinning
system. The resulting yarn is exceptionally soft and well-covered and is
produced at a speed at least 10 times greater than that allowed by the
conventional method. In a test at SRRC, a prototype of the tandem spinning system produced a
bicomponent yarn with a polyester core and a cotton sheath. The yarn was
converted to twill fabric that had an almost 100-percent-cotton surface. After
it was heat-set, the fabric showed unusual properties of softness, satisfactory
shrink resistance and acceptable wrinkle resistance upon laundering. ARS, the chief scientific research agency of the
U.S. Department of Agriculture, has a patent
on the system, which is available for licensing (Patent 5,802,826). U.S. Department of Agriculture | |