Sustainable dyeing and printing with natural colours vis-à-vis preparation of hygienic viscose rayon fabric

Abstract

The use of natural colorants will offer no effluent problem and will provide a natural finish to textiles treated with these materials. However natural dyes are known to have limitations like lower dyeing efficiency, process complexity, availability etc. In this work viscose rayon fabrics were coloured with commercially available natural dyes namely, madder, harde and turmeric with the help of metallic salts. Exhaust dyeing is the most common method to carry out dyeing of goods. In spite of that the main problem with conventional exhaust method especially when using natural dyes is low exhaustion. In this study an attempt has been made to overcome this drawback along with minimizing wastage of natural colorants, when dyeing with natural dyes on viscose rayon fabric by using two different padding techniques namely pad-dry-steam and cold-pad-batch; giving encouraging results. Cold-pad-batch technique performed better in terms of shades observed visually, which could not be attained by pad-dry-steam methods. Later on printing was done using the same set of natural dyes on the dyed viscose rayon fabrics with a variety of shades; resulting in moderate to good light fastness and good to very good washing fastness. Finally, bromophenol blue test revealed that these dyed samples developed good microbial resistance too.