β-Cyclodextrin assisted simultaneous preparation and dyeing acid dyes onto cotton fabric

Acid dyes are applied onto the cellulosic textiles through the modification of the textile surfaces with cationic groups. The conventional dyeing of the cellulosic textiles with acid dyes is usually performed over two main steps including, the preparation of the acid dyes and then the applying of these prepared dyes onto modified cellulosic textiles. Herein, a new strategy for simultaneous preparation and dyeing of the cotton fabrics with acid dyes in one step was developed. The innovative strategy was involved in two steps. The first step: β-CDs were grafted onto cotton fabrics through citric acid in the presence of sodium hypophosphite as catalyst and subsequently, the β-CDs grafted cotton fabrics were loaded with naphthols. In the second step; the acid dyes were formed directly onto the modified fabrics by the in-situ coupling of the diazonium salt of the different amines with the naphthols/β-CDs grafted cotton fabrics complexes. The amounts of the grafted β-CDs on the cotton fabrics were evaluated by qualitative and quantitative methods. The cotton fabrics were evaluated by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Finally, the coloration and fastness properties of the dyed modified cotton fabrics were investigated. The results displayed that, the dyed modified cotton fabrics were shown the different color shades according to the naphthols and amines with remarkable fastness properties. [Display omitted] •Facile development of dyeing of cotton fabrics with acid dyes.•Simultaneous preparation of colorant and dyeing of cotton fabrics in one step.•In-situ formation of acid dyes onto the cotton fabrics assisted with β-cyclodextrin as hosting molecules.