Depth assessment for mixture shades

A proposed method of determining standard depth based on lightness at maximum chroma produced a gap in the standard depth curve in the green sector of the hue circle. The technique described in this paper enables the gap in the green region, previously obtained for single dyes, to be filled. Mixture shades of yellow and turquoise reactive dyes on cotton were produced and the colours compared with the colour predicted by a commercial match prediction program. The differences were sufficiently small to enable predicted shades to be used with confidence, obviating the need for physical dyeing. A range of green shades was generated by entering colorant concentrations on a trial and error basis, and from this a series of greens evenly spread through that segment of the hue circle was selected. The proposed method therefore appears to apply both for substrates dyed with single dyes and mixture shades.