Sustainable Dyeing of Wool by Natural Dyes in Conjunction with Natural Mordants

Indians are known as precursors in natural dyeing art. Even though home-grown knowledge mode has been experienced in the past over the years but applications of natural colourants have been reduced due to lack of methodical knowledge of extraction, dyeing procedures and documentation over generations. This leads to failure to commercialisation of natural colourants. All the synthetic colourants being used for dyeing textiles now a days have dire environmental concerns due to their toxicity and non-biodegradability. They generate water pollution, are carcinogenic along with waste disposal problems. Natural colourants are rational solution to all these problems. Thus, it is obligatory to evolve suitable technology for extraction and sustainable applications of natural dyes on textiles. Present study is an approach to extract natural colourants from a variety of plants sources such as Kalanchoe-pinnata, papaya, peepal and banyan using specific extraction techniques to achieve maximum yield in K/S and antioxidant properties. These four natural extracts were tested for their dyeing potential on wool fabric. Dyeing was performed using three different mordanting techniques (pre, meta and post-mordanting) wherein different natural mordants such as harda, amla, pomegranate and orange as well as synthetic mordants such as alum, copper sulphate and ferrous sulphate were used to fix dye on to the textile substrates. A rainbow of natural colours was obtained with varied shades of each colour. Finding of the study shows that all the four natural extracts give satisfactory wash and light colour fastness. The natural mordants give comparable results with synthetic mordants. Thus these natural extracts along with natural mordants can be explored at industrial scale for sustainable colouration of wool.