Synthesis of active methylene azo disperse dyes based on 4-Amino-3-Nitrobenzaldehyde as diazo component and their application on polyester and Nylon 6.6 fabric

Active methylene azo disperse dyes were synthesized and characterized. A good percentage yield of each of the dyes were obtained in the range of 58-82 %. The dyes have well defined melting points in the range of 270 – 404 C. The visible absorption spectra of the dyes showed that the dyes absorbed maximally within the visible region of the electromagnetic spectrum. The results of halochromism of the dyes showed that the dyes exhibited both negative and positive halochromism. The molar extinction coefficient of the dyes was generally high indicating high hue strength. On application of the dyes on fabric, a high percentage exhaustion of 73 and 69 percent was obtained on polyester and nylon 6.6 fabrics respectively. The assessment of fastness properties of the dyes showed that the dyes have ratings of 4-5 for wash fastness, fastness to pressing and perspiration on both fabrics.