Dyeing of cellulose-based fabrics using dyes extracted from plants

Abstract

Unbleached and bleached woven cotton fabrics were scoured with non-bleach washing powder. The first set of fabrics were mordanted once in a mixture of alum [1:120 (w/v)] and vinegar [1:100 (v/v)] while the second set was mordanted thrice (tri- mordanted); first with alum [1:120 (w/v)], then with tannin [1:500 (w/v)] and finally with alum in water. Cooking overnight soaked inflorescences of Tagetes minuta in water in the ratio 1:25 (w/v) and straining, provided the muchneeded dye-bath. Dyeing was accomplished by soaking the mordanted fabrics in the dye-bath and simmering for 1 hour at various temperatures viz: room temperature, ranges of 50—60 ^oC and 80—90 ^oC. Tests performed confirmed the dye produced as a reactive dye. Cotton fabrics that were tri-mordanted produced brighter golden yellow shades vis á vis those that were singly mordanted in alum and vinegar. The dyeing temperature range of 80—90 ^oC produced uniform dyeing of fabric articles hence the optimal dyeing temperature. A khaki (olive green) shade was produced on fabric articles when 38^o Bé sodium hydroxide solution (8 mL/L) was added to the dye bath. The resultant golden yellow shade obtained from Tagetes minuta inflorescences is a big achievement given that it is a primary colour which can be used to generate other colours for dyeing.