Innovative application of extracted binary colorant from henna and walnut for dyeing of mordanted silk

The revival of natural dyes has once again revolutionized the globe with its aesthetic charm and sustainable behavior. In this study using central design and MW treatment for a selection of dyeing conditions, the binary mixture from walnut and henna as an anthraquinone source of dye has been appraised for silk. Using an extract of 5 pH from binary powder (3 g + 3 g) at 70°C for 65 min having 3 g/100 mL of salt has given better yield (K/S = 6.20), which was enhanced after MW treatment up to 6 min (K/S = 6.66). Color fastness was formed by using Fe ⁺² (pre 3%, post 1%, meta 2.5%), Al ⁺³ (pre 1.5%, post 3%, meta 1%), and Tannic Acid (pre 3%, post 1%, meta 3%) as inorganic mordants onto silk. In comparison, using bio sources, extracts of clove (pre 3%, post 1%, meta 3%), cinnamon (pre 2%, post 1.5%, meta 2.5%), myrobalan (pre 2%, post 2.5%, meta 1%) and red sumac (pre 3%, post 1%, meta 3%) has given colorfast shades also. The ISO standards for colorfastness to light washing and rubbing have shown good to excellent results that reveal the potential of MW treatment, eco-friendly mordanting process, and statistical tool addition for process optimization.