Dyeing properties and color fastness of cellulase-treated flax fabric with extractives from chestnut shell

Flax fabric was pretreated with acid cellulase and then dyed with a natural dye extracted from chestnut shell (EFCS). Suitable conditions were selected for the enzymatic treatment of flax fabric. The dyeing property of pretreated flax textiles during dyeing with EFCS was determined by dyeing experiments through the control variate method. UV-vis absorption spectra of EFCS were recorded to calculate the dye uptake. The colorimetric parameters L*, a*, b*, ΔE, and color strength of samples were measured to select the optimal dyeing conditions. Finally, the fabric was dyed with metal-salt mordant after enzymatic treatment under the optimal treatment condition. The color fastness to washing, rubbing of the dyed samples was determined according to AATCC test methods, whereas the color fastness to light was tested according to the ISO standard. Optimum dyeing results were achieved when dyeing with 16 g/L of EFCS solution at 95 °C for 50 min and at pH 4. The contrast of colorimetric parameters of treated fabric and untreated fabrics indicate that enzymatic treatment improved the softness of flax fabric and slightly enhanced the dyeing behavior of flax during dyeing with EFCS in that the K/S value increased around 15%. Flax fabric dyed without mordant had a shade of yellowish-brow, while the mordanted ones exhibited a variety of pale to dark shades. The overall color fastness of dyed samples showed good level except for fabric mordanted with ferrous sulfate. EFCS dyeing combined with enzymatic treatment is an ecological and promising approach for textile industry.