Effect of washing process of knitted fabrics on the tensile characteristics of blended yarns

The main purpose of this study was to define the effect of washing process of knit wear on tensile characteristics of blended yarns. The tensile characteristics such as specific stress, elastic and remain strains, degree of elasticity and hysteresis of deknitted yarns were compared with the same parameters of deknitted washed yarns. The investigations were carried out with cotton/acrylic (PAN) and wool/acrylic (PAN) ring spun blended yarns. The samples were knitted in a 1x1 rib pattern on a flat V-bed knitting machine in a gauge of 10 E. After knitting the samples were washed several times (1, 3 and 5 cycles) in an automatic washing machine according to the programmes for cotton and for wool fabrics and then were dried by spreading them on a horizontal surface. It was stated that after washing process the cotton/PAN blended yarns had lost their elasticity. The values of remain strain and hysteresis have increased. The effect of washing process on tensile characteristics for wool PAN blended yarns wasnt significant. It was determined that all tested indices of yarns depend on the value of total strain, which was kept at the level of 2, 4 and 6%.