Journal of Textile Science & Engineering

Development of Directionally Oriented Compressive Weft Knitted Fabrics

Abstract

Cruz J, Sampaio S and Fangueiro R

Polyamide/elastane knitted fabrics with directionally oriented compressive ability was studied. Knitting designs with coursewise, diagonal, walewise, and both coursewise and walewise compressive orientations were created and analysed at four different angles (0º, +45º, -45º and 90º) and up to 50% elongation. At the same stretching and same direction (angle), the tensile force was higher for samples from Serie B (only the elastane was producing miss stitches) than for samples from Serie A (polyamide and elastane yarns were simultaneously producing miss stitches), in most of the cases. There are higher differences between tensile force values of samples from Serie B with the different number of miss stitches, however, very little difference in tensile force values is seen between samples from Serie A with the different number of miss stitches, in most of the cases. Also the tensile force is the highest when samples from Serie B with walewise compressive orientation are stretched at 90º direction, the tensile force value was two times and half higher than that of the same compressive orientation but from Serie A. At 0º direction, the force values of the samples with coursewise compressive orientation from Serie A were higher than that of samples from Serie B due to miss loops force orientation. At the +45º and -45º directions, the force values of the two Series are similar, showing that the designs and the yarns used are less important due to force orientation. Fabrics with diagonal compressive orientation have force values similar among each sample, in all four directions, the diagonal structure enables the control of fabric anisotropy. The prediction of force values in relation to the number of miss stitches sequences and in relation to the different angles are made using regression model. This analysis helps engineer compressive devices with adjustable and directionally oriented stretch structures.