Colorimetric studies of some newly synthesized bisazo reactive dyes

A series of cold brand bisazo reactive dyes (4a-h) were obtained by the coupling of tetrazotised 4,4′-methylene-bis(2-methyl-5-nitro aniline) (2) with various cyanurated coupling components (3a-h) in good yield. Their dyeing performances as reactive dyes have been assessed on silk, wool and cotton fabrics. These dyes were characterized by UV-Vis, FTIR, 1H NMR spectroscopic techniques elemental analysis. The percentage dye bath exhaustion and fixation on different fibers were found to be very good. The dyed fabric showed moderate to very good light fastness and good to excellent washing and rubbing fastness properties. Spectral properties and colorimetric data (L∗, a∗, b∗, C∗, H∗, K/S) have also been studied in detail.