This fibre was launched in 1959 by an American producer, who is still their major producer in the world. Its use became however widespread only some years ago when the stretch comfort became a must, so that, at a certain moment, available capacities were no longer sufficient to cover the market demand, and expansions and new plants had to be provided. Some new producers were also attracted by this promising market outlet.
Concerning this leading fibre, it has to be taken in mind that the yarn, although looking like a single continuous filament yarn, is actually composed of a bundle of thin filaments joined together. Main end-uses are: stockings and panty-hoses, tubular knit fabrics for ladies' underwear and sportswear, warp knit fabrics for ladies' lingerie and swimwear, warp knit fabrics for corsetry and sundry applications.
The elastomeric yarn is used in different percentages, depending on type of fabric and on its end-use; even only 2% is sufficient to improve the quality of the product by imparting liveliness, drape and better recovery properties. The yarn has the same dyeability and processing characteristics as a synthetic fibre and can be integrated, in the nude state, into many textile structures. It can however be covered with another yarn
or with another fibre. The covering can be either single or double; alternatively it is possible to produce stretch core yarns which, during weaving or knitting, are doubled with non-elastic yarns, thus obtaining fabrics of greater value, more comfortable and with better wear properties.
A third alternative is interlacing: an anelastic multifilament yarn is caused to pass through an air jet together with the strained elastomeric yarn. As a result of an air jet, the yarns get interlaced and the elastomeric yarn gets partially covered.
