Investigating cotton dyeing using exotic wood waste sawdust

Investigating cotton dyeing using exotic wood sawdust. The study investigated the possibility of using 
extracts from various species of exotic wood, obtained from waste sawdust, for dyeing cotton fabrics. Material 
from Obeche, Iroko, Merbau, Apple tree, American walnut, Tulip tree, Cumaru and Rosewood were used for the 
tests. Solutions of oxalic acid, tin chloride, aluminum sulfate and ferric chloride were used as mordants, along with 
no-mordant tests. The color was determined in the CIE L*a*b* coordinate system. Color fastness was tested using 
n-hexane for dry cleaning and acidic, alkaline and hydrogen peroxide bleach solutions. The results showed a strong 
dependence on the type of wood, the mortar used and the washing agent and covered a wide spectrum of color 
intensity and fastness. The best results were obtained for Rosewood, Merbau and Apple trees, while Tulip tree and 
American walnut turned out to be practically useless. Among the mordants used, the most intense colors were 
produced by metal salts, including ferric chloride, which strongly darkened fabrics. Dry cleaning proved to be the 
mildest of those tested, with the least effect on color fading.

