2.2. Instruments
The mordanting and dyeing processes were conducted using a Gyrowash machine (James H. Heal & Co. Ltd., England). A UV–visible spectrophotometer (Halo DB-20, UV-Vis Double Beam Spectrophotometer, Australia) was used for absorbance measurement using quartz cells of path length 1 cm. The CIE L*, a*, b* and color strength in terms of K/S values of dyed samples were measured using a spectrophotometer (Hunter Lab Color Quest XE, USA) with illuminant D65 at 10 degree observer.