Optimization of extraction and dyeing parameters for dyeing of khadi cotton fabric using waste/used marigold flower petals (Tagetes erecta)

Abstract

The aim of the present study is to standardize a protocol for optimization of pre-treatment, mordanting and dyeing of cotton khadi fabric with waste marigold flower petals. The effects of different single and combined double mordanting on dye-ability and colour fastness properties have been studied after optimization of aqueous extraction of marigold flower as natural dye. Mordants used are potash alum, aluminium sulphate, stannous chloride as metallic salt mordant and harda (myrabolan) from natural source as mordant assistant. After finalizing the mordants, dyeing process variables are standardized for dyeing cotton khadi fabric with waste marigold flower extract as selective natural dye applied on 3% H₂O₂ (30%) bleached cotton khadi fabric. Dyeing process variables studied are dyeing time, temperature, MLR, pH, mordant concentration, dye concentration and salt concentration for dyeing with prefixed mordant. Colour fastness to washing, rubbing, light and perspiration against use of different mordants and also against different dyeing process variables are also investigated. The results indicate that, this particular natural dye renders better appreciation of colour yield by pre mordanting with 15% aluminium sulphate and harda (50:50) as compared to other single mordants (potash alum and stannous chloride) and double mordants used. Use of double mordant in 15 % application level, shows maximum K/S value with overall good colour fastness than others.