Dyeing cotton/polyamide blend fabrics with 1 : 2 metal complex acid dyes

The ability to dye blends of cotton and polyamide fibers has attracted much interest, especially in the case of wool/cotton blends, with success havin g typically been achieved using complicated procedures. In this work sample s of wool/cotton, silk/cotton, and nylon/cotton fabrics were pretreated usi ng a long liquor exhaustion method using different pretreatment agents and subsequently dyed with several 1:2 metal complex acid dyes. The pretreated dyeings showed excellent dye uptake with respect to their untreated counter parts. The blended fabrics that had been pretreated showed only slight diff erence in color or in depth of shade between the cotton portion and the pol yamide portion. The color difference visible between the two fibers and the overall color strength of the dyeing was dependent upon the pretreatment a gent used.