Synthesis and dyeing performance of some amphiphilic naphthalimide azo disperse dyes on polyester fabrics

A series of monoazo disperse dyes were synthesized by coupling diazotized 4-amino-N-dodecyl-1,8-naphthalimide with N,N-dialkyl anilines and naphthol derivatives. The synthesized intermediates and the dyes were characterized using FTIR, 1H-NMR, 13C-NMR, mass spectroscopy and elemental analysis (CHN). Visible absorption spectra of the dyes were examined in solvents of different polarities. The electronic absorption spectra cover a wavelength (?max) range of 515-535 nm in DMF at uniformly absorption intensity between 1.59-3.00?104 L mol-1 cm-1. The dyes gave deep and bright intense hues of light violet, maroon, pink and neon red on polyester fabrics. The dyes generally showed good washing and perspiration rating but poor to moderate light fastness properties on woven polyester fabric and could be recommended for commercial outlets.

Synthesis and evaluation of novel antibacterial monoazo disperse dyes based on sulfonamide derivatives on polyester

Purpose This paper aims to present the design and synthesis of a series of novel antibacterial monoazo disperse dyes based on sulfonamide derivatives to combine the dyeing and functional finishing steps on polyester into one process. Design/methodology/approach The diazoniom salts of sulfonamides, namely, 4-amino-N-(2-pyrimidinyl) benzenesulfonamide, 4-amino-N-(4-methyl-2-pyrimidinyl) benzenesulfonamide and 4-amino-N-(4,6-dimethyl-2-pyrimidinyl) benzenesulfonamide were prepared and then coupled to N,N-diethyl aniline, N,N-dicyanoethyl aniline and N,N-dihydroxy ethyl aniline, respectively, to produce the dyes. Findings The structures of the dyes were characterized using their spectral data (FTIR, 1H-NMR, UV-Vis) and elemental analysis. The results indicated that all the dyes exhibit positive solvatochromism in more polar solvents. Dispersion of the dyes was prepared in water and applied to polyester fabrics. The synthesized dye 3a which had good exhaustion on the fabric (89.98 per cent) and were tinctorially stronger (28899 l/mol.cm) showed higher visual colour yield (16.51). The antibacterial efficacy of the dyes was assessed, and they showed activity against both gram-positive and gram-negative bacteria but in different levels depending on their structures. Research limitations/implications A simple way to combing functional finishing and dyeing in one process was successfully performed via design and synthesis of disperse dyes with an antibacterial moiety incorporated into dye molecules. The dyes were fully charaterized and evaluated on polyester. Originality/value A series of novel antibacterial monoazo disperse dyes based on sulfonamide derivatives were synthesized. The authors studied their application for dyeing of polyester fabric. The dyes offered good results in terms of preparation, yield, purity, visual colour yield, fastness properties and activity against bacteria.

Photostability of Monoazo Disperse Dyes in Different Solvents

Twelve monoazo disperse dyes were synthesized and then characterized by melting point (m.p.) measurement, elemental analysis and1H-NMR. The photostability of monoazo disperse dyes in solvents with different polarities was evaluated thereafter the dyes in each solvent were irradiated with visible light for 8 hours. The percentage of photostability of the dye decreased from the initial value in the range of 5-10%. The photostability was affected by the substituted group of the dyes regardless of the solvent used. Different R1group on the diazo component increased the photostability in order of H˃CN˃Cl. The photostability of the dye was also higher when R2group on the coupling component was a methyl group.