Chemical and Physical Evaluation of Natural Dyes from Hibiscus Sabdariffa Linn (Zobo), Bamphia Nitida (Camwood) and Indigofera Tinctoria (Tropical Indigo Plant)

Extraction and characterization of natural dye from Hibiscussabdariffalinn (Zobo), Bamphianitida (camwood) and Indigoferatinctoria (Tropical indigo plant) was studied to ascertain the optimal yields of dye extract using different solvents. Different plants gave yields within the range of 0.5-3.5g. The optimal yields of dye extracts were subjected to UV-analysis. The absorption peaks for Hibiscussabdariffalinn (zobo), Bamphia nitida (camwood) and Indigoferatinctoria (Tropical indigo plant) were obtained using a UV-spectrophotometer and the maximum absorptivity using ethanol, methanol and acetone solvents were found to be 2.350, 3.524 and 1.560 respectively. The highest peaks were deduced from the graph at 500xmax for Hisbiscussabdariffalinn (zobo) 340xmax for Indigofera tinctoria (Tropical Indigo plant) and 480xmax for Bamphia nitida and azo group. The pretreatment of the cotton fabric with two different mordants (Aluminum potassium sulphate and potassiumdichromate) showed that the mordanted cotton fabric using potassium dichromate was unable to penetrate the dyestuff while the mordanted cotton fabric using aluminium potassium sulphate was able to penetrate the cotton fibric. The mordanted cotton fabric had a better absorption of dye compared to the unmordanted fabric. The result of fastness test showed that cotton fabric has a good affinity for dye.