Color properties of cellulase-treated cotton denim fabric manufactured by torque-free ring spun yarn

Torque-free ring spinning is a new spinning technology that produces yarns with low twist and balanced torque. This study examined whether the impact of cellulase treatment was different on denim fabrics having torque-free ring spun yarn in the warp direction. Commercially produced torque-free ring spun cotton yarn was used for manufacturing denim fabric. One specimen of denim fabric had torque-free ring spun yarn in the warp direction and conventional ring spun yarn in the weft direction while the other had normal conventional ring spun yarn in both warp and weft directions. Both warp yarns of the fabrics were dyed with the same indigo dyeing process. The denim fabric samples were treated with neutral cellulase under the same conditions, and weight change and color properties, such as reflectance, K/S value, CIE Lab values, and color fastness ratings, were measured. Experimental results showed that the weight loss percentages of the denim fabric samples after cellulase treatment were very similar. The specimen with torque-free ring spun yarn in the warp direction produced a lower reflectance value and higher color yield compared with the specimen with conventional ring spun yarn in both warp and weft directions. Meanwhile the denim fabric manufactured by torque-free ring spun yarn demonstrated a larger color difference but no significant effect on colorfastness properties after cellulase treatment.