The effect of tetrakis(hydroxymethyl)phosphonium chloride (THPC) and peroxydisulfate (PS) anion pretreatments on the dyeing properties of wool with metallized azo dyes was studied and characterized. Chrome-metallized azo dyes containing pyrazolone or acetoacetanilide moieties dyed THPC and PS-treated wools to different shades than those found for untreated wool, whereas treated and untreated wools dyed with chrome-metallized azo dyes containing aromatic benzenoid rings on both sides of the azo group gave much smaller color differences. The particular mordant used did not significantly affect the nature of color differences observed when treated and untreated wools dyed with mordant dyes containing a pyrazolone moiety were metallized; however, the pH-sensitivity of the mordant-dyed wools was reduced by metallization, with sodium dichromate and cuprous sulfate metallization providing the greatest degree of stabilization.
STUDIES ON THE DYEING PROPERTIES OF ACID AZO DYES (PART IV)