Abstract: The color stability of tussah silk fabrics which were dyed with natural dye hematoxylin using iron mordant dyeing and fixing treatment was studied by testing the color indexes (L﹡, a﹡, b﹡, c﹡values and K/S value) and color fastness of the dyed silk fabric. It was found that the color and color stability were both influenced and the color stability of the dyed fabric could be increased in dye bath with different pH value when the dyed fabric by treated with fixing agent NC. The color fastness to washing of the dyed fabric could be significantly improved and color stability could not be enhanced using iron mordant dyeing method. By using iron mordant dyeing and fixing treatment, photo stability and peroxide stability were improved and the color stability could not be increased under high temperatures. Fixation made the dyed fabric brighter.

Key words: color fixation, iron mordant dyeing, dyed tussah silk, hematoxylin dye, stability