Potential Human Hair and Sheep Wool Dyeing Characteristics of Hair Colour Formulations Prepared from Four Vegetable Dyes.

Abstract

Man insatiable desires often leads him to many choices. Some functional, others for the purpose of decoration or acceptability. The dyeing of hair can be comfortably placed in any of the three categories. The production of hair colours is a multi-billion dollar industry that involves the use of both plant-derived and synthetic dyes. Unlike synthetic dyes which can be toxic and harmful to the environment; natural dyes are biodegradable, non-toxic and compatible with environment. In the present study the comparative black – brown colouring effect of seven dye formulations made from ethanol and chloroform extracted pigments of some local dye yielding plants; Lawsonia inermis, Loncocarpus cyanescens, Pterocarpus osun and Trema orientalis on grey human hair and sheep wool was observed and recorded after two hours of dye uptake; storage at room temperature for 4 days and exposure to sunlight for 4 days. % yield of extracted dye ranged from 1.04 - 3.20 in the order Lawsonia inermis < Trema orientalis < Lonchocarpus cyanescens < Pterocarpus osun dye. The colours of the dyes obtained were orange (Lawsonia inermis), yellow (Loncocarpus cyanescens), dark red (Pterocarpus osun) and dark green (Trema orientalis). The human hair took up the dye more readily than the sheep wool and the black-brown colouring effect was maximum with formulation 7 and in the order PF 7>PF 3 > PF 5 > PF 4 > PF 1> PF 6 >P2 with the colour being retained for the greatest period of time at room temperature while fading gradually with the length of exposure to sunlight for both human hair and wool. The colour deepened however for sheep wool, with length of stay at room temperature. In conclusion, the natural dye formulations coloured the hair better than sheep wool, it may therefore be suitable for the formulation of hair colouring solution, after toxicity tests, colour fixing and modification studies have been carried out on the dyes. Keywords: Lawsonia inermis, Loncocarpus cyanescens, Pterocarpus osun, Trema orientalis, Human hair, Sheep wool, Vegetable dyes.