Investigation On Tensile And Elastic Recovery Properties Of Seamless Underwear Knitted Fabrics

Seamless knitted underwear called the second skin of the body is almost fully-fashioned byseamless knitting technology, which can produce definite pressure that will keep the size andshape on the human body. The seamless knitted underwear attains its shape by changing differentstitches on different parts of the body. In order to make the clothes more comfortable andunconstrained, the fabric should follow performance of the skin closely when one moves. In otherwords, the fabric stitches of every part of the seamless knitted underwear not only guarantee thatthe elastic elongation and elastic recovery rate must fit the skin extension when one moves, butalso ensure that the pressure produced by the clothes is the most suitable to the body. The structurecharacteristics of most seamless knitted underwear and the weft knitted fabrics are the same. Andthe fabric wale and course have the most significant contact. The loop transfer will happen whenstretches. The elastic deformation on many parts such as the elbow is not only on single directionwhen moves. Therefore, in order to know the characteristics and mechanical properties of eachstitches of seamless knitted underwear deeply, it’s necessary to investigate the single or biaxialtensile and elastic recovery properties and the relationship with the pressure properties of differentseamless knitted underwear fabrics.The paper firstly had a brief introduction of the structure and the knitting principle of eachfabrics, and nine different fabric samples including jersey plating, mock rib and cross stitch wereprepared on a single seamless knitting machine. After relaxation processing, the samples attainedthe stability as ready to wear. To find out the tensile and elastic recovery properties of the samples,single and biaxial tensile experiments are made by the X-Y biaxial electronic tester. It is concluded by dater analyses and polynomial fitting that under the same extens ion rates, the jerseyplanting fabric exhibits the smallest tensile force and poorest elastic recovery; the tension forceand elastic recovery of the mock ribs rises with the increase of the length of float; and1+1crossstitch with tight structure shows the largest tensile force but the poorer elastic recovery.Under the condition that the raw material of the yarn and the yarn feeding tension keeps thesame but changing the sinking depth, taking the1+1mock rib for instance, tensile experiment wasmade, and conclusions are that under the same extension rates, the tension force and the surfacedensity reduced and the loop length rose with the increase of the sinking depth.To find out the relation between the tensile and elastic recovery properties and the pressureproperties, the three-dimensional s imulation of pressure test of different seamless knitted fabricswas made. After the contrast analyses of the data, we find that under the same extension rates, theregularity between the dynamic or static pressure and the tension force looks is the same; thetendency between the dynamic or static fatigue and the elastic recovery rates is opposite, but theyall reflect the same fabric elasticity. The detailed data of each experiment have the definitesignificant guide to the stitch design of the seamless knitted underwear.