2.2.5. Dyeing. Dyeing was carried out in exhaust method
with the dye extracts as per standard dyeing conditions
recommended for silk fabric [18]at80
∘
Cfor60minutes
under pH 5, keeping material to liquor ratio 1 : 50 in a IR
sample dyeing machine. Opticid PSD (1.5 g/L) was used as a
buffering agent in the extracted dye liquor.