Table 6 shows the effect of pre-mordanting with Zr-oxychloride
on the K/S as well as washing and rubbing fastness properties
of the obtained natural dyeings. For a given set of pretreatment
and dyeing conditions, it is clear that: (i) pre-mordanting with the
nominated mordant brings about a significant enhancement in the
K/S values of the obtained dyeings, regardless of the used natural
dye, (ii) the extent of improvement is governed by the physical
and chemical states of the dye and degree of fixation, (iii) premordanting
followed by dyeing gives dyeings with better fastness
properties than those dyed without pre-mordanting and, (iv) the