The effects of heat-setting on the properties of polyester/viscose blended yarns

30 tex and 20 tex yarn bobbins consisting of 67% PES - 33% viscose were subjected to heat-setting at 90 degrees C & 110 degrees C, and under a pressure of 630 mmHg in order to investigate the effects of heat-setting conditions on the properties of twisted yarns. Both heat-set and unset yarns were dyed. The tensile strength properties (tenacity and elongation at break) of each yarns were measured before heat-setting, after heat-setting and after dyeing. The inner middle and outer sections of the yarn bobbins were measured with a spectrophotometer to fund differences in color As a result, heat-selling and dyeing processes were found to be effective in the tenacity and elasticity of yarns.