Dyeing and Colorfastness Characteristics of Direct-Dyed Ramie in Comparison to Flax and Cotton

A comparison of dyeability and colorfastness characteristics of ramie, flax, and cotton yarns dyed with six direct dyes was made. When dyed in a common dyebath, the shade produced on each of the three fibers varied. Although the magnitude of difference varied among the dyes, there was consistently less difference between the shades produced on ramie and flax (mean Δ E = 2.6) than between ramie and cotton (mean ΔE = 8.7). Even when ramie had a lower actual dye content than either flax or cotton, its relative depth of shade (L-value) was higher. This can be attributed to optical effects arising from the comparatively large cross-sectional size of the fiber and its highly ordered structure. The colors produced on cotton were consistently brighter than those achieved on ramie or flax. This occurred because cotton, being a thinner fiber, contained more dye per volume fiber than ramie and flax. Little difference in colorfastness to laundering was seen among the three fibers.