Dyeing of silk using binary mixture of harmal seeds and safflower petals

Abstract

This study introduces a novel, sustainable binary extract-based dyeing strategy for silk, utilizing natural colorants sourced from harmal (Peganum harmala) seeds and flowers of safflower (Carthamus tinctorius) petals. A central composite design was employed to systematically optimize essential dyeing parameters, fastness properties, and the use of mordant, and was done with the objective of maximizing color strength (K/S). After application of eco-friendly chemicals and bio-coating of silk, the dyed silk exhibited superior colorfastness properties, achieving ratings of 4–5 for washing, 4–5 for rubbing (dry and wet), and 5–6 for light fastness, confirming the durability of the coloration. The biological activities have shown good attributes of binary plant colorant for silk beneficial for the community. The use of central composite design in conjunction with microwave treatment has enabled the dyeing of silk at 70°C for 40 min with a binary extract at pH 5 obtained from 6 g of harmal and safflower binary powder. It is concluded that binary agrowaste can be used as a value-added natural dye for fabric using this modern approach and stable colorfast shades can be obtained using eco-friendly additives.