Extraction, identification and dyeing studies of Isosalipurposide, a natural chalcone dye from Acacia cyanophylla flowers on wool

► Chalcone dyes are very old natural colorants but they are not mainly investigated on textile dyeing. ► A chalcone compound Isosalipurposide was qualitatively isolated from the flowers of Acacia cyanophylla, a cheap and abundantly available plant in Tunisia, and used to dye woollen fibres at different dyeing conditions. ► The results indicate that Isosalipurposide must be used at low dyeing temperatures in order to avoid its degradation and consequently a fall of the colour yield. ► The obtained shades were bright yellow with good colour fastness properties. ► Post-mordanting improved generally light fastness especially in the case of zinc sulphate as mordant. A chalcone compound Isosalipurposide 1 was qualitatively isolated from Acacia cyanophylla yellow flowers. The dyeing of wool fabrics with this chalcone compound as a natural dye has been studied. The effect of dye bath pH and dyeing temperature were investigated. The obtained shades were bright with generally a good fastness. A post-mordanting method was used in the dyeing of wool with this chalcone dye. It was found that, generally, mordanting improved light fastness especially in the case of zinc sulphate.