Extraction of natural dye from camphor leaves and its silk dyeing

A natural dye is extracted from camphor leaves and applied to silk dyeing.Influence of extraction condition on extraction yield,such as NaOH concentration,extraction temperature,extraction time and material ratio are studied.Factors exerting influence on dyeing results including dyeing pH,dyeing temperature,dyeing time,Na2SO4 concentration,as well as effects of mordant type and method on dyeing properties and fastness are discussed.The results show that alkaline condition is more conducive to extraction.The optimum extraction conditions are NaOH 0.3 mol/L,extraction at 90 ℃ for 80 min,material ratio 1∶30.The optimized dyeing process is as follows: pH value 3.00～3.50,dyeing at 90 ℃ for 60 min,bath ratio 50∶1.Furthermore,the silk fabric mordant dyeing with alkaline extracts have improved color fastness.