abstract
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 offlax fabric. The dyeing
property of pretreatedflax textiles during dyeing with EFCS was determined by dyeing experiments
through the control variate method. UVevis absorption spectra of EFCS were recorded to calculate the
dye uptake. The colorimetric parametersL*,a*,b*,DE, 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 offlax 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.