Dyeability and Dyeing Properties of Disperse disazo Dyes on Polyester and Nylon Fabrics

Abstract

The four properties in general the dye must possess are intense colour, solubility in aqueous solution, substantivity and colorfastness. The modern tendency in textile dyeing is towards insistence on dyes which possess good fastness properties to light, washing, rubbing and bleaching. Further it may be considered as an ingenious developments and modification of dyeing. Dyeing of fiber depends on the secondary forces between dye and fiber and penetration of the dye into fiber. Dyeing therefore implies some affinity between the fiber and dyes. Thus the dyes which possess this affinity are termed as substantive dyes. All fibers do not possess affinity for the same dyes for example many dyes for wool and silk have little affinity for cotton and rayon. Therefore dyestuff for dyeing of textile is generally classified according to their method of application. polyester is quantitatively the most important synthetic fiber because of inexpensive production from petrochemical raw materials and excellent textile properties alone and in combination with natural fibers is the universal applicability. Polyester fibers are hydrophobic and can be dyed easily with water insoluble small molecular dyes. Although a large variety of disperse dyes are available for coloring polyester fibers, most of disperse dyes are azo compounds.