The Coloration of Wool and Wool Blends with Disperse Dyes

Wool has a low affinity for disperse dyes, consequently they give low colour yields, pale colours and dyeings of poor wet fastness. However, by treating wool with simple organic compounds, and applying disperse dyes to the treated material using dry heat at 180 – 200 °C, or steam at 150 – 180 °C, satisfactory dyeings can be obtained. Various compounds have been evaluated, including amides, certain polyhydric alcohols and certain hydroxycarboxylic acids; glycerol, thiodiethylene glycol and lactic acid are particularly effective. The compounds are applied to the fibres from aqueous solution by a pad-dry procedure, in amounts ranging from 10 – 30 % o.w.f.