Dyeing of Cationized Cotton with Natural Colorant from Purple Corncob

In this investigation, dyeing of cotton fabric with natural dye extracted from purple corncob was attempted by means of pretreatment with a cationic agent, 3-chloro-2-hydroxypropyltrimenthylammonium chloride (CHTAC). Maximum color yield results were achieved when the fabric was pretreated with CHTAC at a concentration of 125g/L, followed by dyeing at 100 degrees C for 30min in a dye bath adjusted to pH 9. The influence of meta- and post-mordanting with AlK(SO4)(2), CuSO4, FeSO4, and gallnut was subsequently explored. Compared with the unmordanted sample, post-mordanting enhanced K/S values and slightly improved light fastness, but both meta- and post-mordanting caused a reduction in wash fastness from an excellent to a fair level, with the exception of CuSO4. Meanwhile, mordanting with gallnut increased the acid and alkaline perspiration fastness from a poor and fair to a good level.