Hari Raghav Maradiya

Synthesis and Dyeing Performance of Some Novel Heterocyclic Azo Disperse Dyes

The synthesis of some novel heterocyclic azo disperse dyes derived from 5-acetyl-2-amino-4-methylthiazole (1) using various N-alkyl derivatives of aniline (2a-e) and their dyeing performance as disperse dyes have been assessed on polyester and nylon fabrics. The spectral properties of these dyes were measured. The dyed fabrics show moderate to good light fastness, very good rubbing, perspiration, washing fastness and excellent sublimation fastness. These dyes have been found to give bright orange-red colour hues with very good depth and levelness on fabrics. The dyebath exhaustion on fabrics has been found to be very good.

Synthesis, characterization and application of monomeric and polymeric dyes based on N-arylmaleimides

Novel monomeric dyes have been prepared by diazotization of 2,6-dibromo-4-nitroaniline and coupled with various N-arylmaleimides. The polymeric dyes were prepared by free radical polymerization of monomeric dyes. The resultant dyes were characterized by IR spectral studies, intrinsic viscosity, thermogravimetry analysis, elemental analysis and molecular weight was characterized by VPO. The monomeric dyes were also characterized by elemental analysis and IR spectra. The purity of all the dyes were checked by thin layer chromatography and they have also been applied on nylon and polyester fibres as a disperse dye. These dyes have been found to give various colour shades with good to very good depth and levelness on each fibre. The percentage dye bath exhaustion on different fibres have been found to be good to very good. The light, washing, rubbing, perspiration and sublimation fastness properties of the dyed fibres has been found to be very good to excellent.

Synthesis and Application of Disperse Dyes Based on 2-Aminothiazole Derivatives

A series of novel monoazo disperse dyes based on 2-amino-5-nitro-4-(p-nitrophenyl)thiazole were prepared using various N,N-dialkylaniline derivatives as the coupling components. The spectral properties in the IR and visible range of the dyes were investigated. The dyeing performance of these dyes was assessed on nylon fabric. These dyes were found to give a wide range of color shades from reddish brown to indigo with excellent brightness, levelness, and depth on nylon fabric. The dyed fabric showed fairly good light fastness, good to excellent fastness to wash and perspiration, and excellent fastness to sublimation. The dyebath exhaustion and fixation of the dyes on nylon were found to be very good and acceptable.

Thiazole based disperse dyes for nylon and polyester fibers

Nine disperse dyes have been synthesized by diazotization of 2-amino-4-(p-nitrophenyl)-5-nitrothiazole and coupled to substituted N-alkylanilines. Spectral properties in the IR and visible range of the dyes obtained were investigated. The dyeing performance of these dyes was assessed on nylon and polyester fibers. These dyes were found to give reddish brown to bluish violet shades on dyeing with very good depth, brightness and levelness on nylon and polyester fibers. The dyed fibers showed fairly good light fastness, very good to excellent fastness to wash, rubbing, perspiration and excellent fastness to sublimation. The dyebath exhaustion and fixation on the fiber were found to be very good.

Dyeing performance of disperse dyes based on 2-aminothiazole for cellulose triacetate and nylon fibers

A series of monoazo disperse dyes based on 2-amino-4-phenylthiazole was prepared using variousN,N-dialkylaniline derivatives as the coupling component. The dyes were characterized by IR spectral studies, visible absorption spectroscopy and elemental analysis. The dyeing performance of these dyes was assessed on cellulose triacetate and nylon fibers. These dyes were found to give a wide range of colour shades varying from bright red to royal blue with very good depth, brightness and levelness on fibers. The dyed fibers showed good to very good light fastness and very good to excellent fastness to washing, perspiration, rubbing and sublimation. The dyebath exhaustion and fixation on the fibers were found to be very good.

Synthesis of novel azo dyes containing the thiophene moiety

A series of disperse dyes have been synthesized by diazotation of 2-aminothiophene derivative and coupling with various N-arylmaleimides. The dyes were characterized by IR spectral studies, visible absorption spectra, and elemental analysis. The dyeing performance of these dyes was assessed on nylon fabric. These dyes were found to give yellowish brown to reddish violet shades on dyeing with very good depth, levelness, and brightness on fabric. The percentage dyebath exhaustion and fixation on fabric was found to be very good. The dyed fabric showed poor light fastness and good to excellent fastness to washing, rubbing, perspiration, and sublimation.

Polymeric dyes based on thiadiazole derivatives

A series of polymeric dyes were synthesized by free radical addition polymerization of monomeric dyes. The 2-amino-5-mercapto-1,3,4-thiadiazole was diazotized and coupled with various N-arylmaleimides to give monomeric dyes. All the polymeric dyes were characterized by elemental analysis, infrared spectroscopy, visible absorption spectroscopy, viscometry, and thermogravimetric analysis. Color and dyeing properties of the polymeric dyes were discussed by comparing them with those of the corresponding monomeric dyes. The dyeing performance of these dyes was assessed on nylon fiber. These dyes were found to give various color shades with good to very good depth and levelness on the fiber. The dyeing of the monomeric dyes showed moderate fastness to light and good to excellent fastness to washing, perspiration and sublimation and their corresponding polymeric dyes showed excellent fastness properties. The dyebath exhaustion and fixation on nylon fiber has been found to be good.

MONOMERIC AND POLYMERIC DISPERSE DYES BASED ON HETEROCYCLIC COMPOUND FOR HYDROPHOBIC FABRIC

A series of monomeric dyes have been prepared by diazotization of 2-aminothiadiazole and coupled with various N-arylmaleimides. The polymeric dyes have been prepared by free radical polymerization of monomeric dyes and they are characterized by intrinsic viscosity, molecular weight by vapor pressure osmometry, thermogravimetry analysis, IR, visible spectroscopy, and elemental analysis. The monomeric dyes have also been characterized by elemental analysis and IR spectra. The purity of all the dyes have been checked by thin layer chromatography and also applied on polyester fiber as a disperse dye. Color and dyeability of the polymeric dyes have been discussed by comparing them with their corresponding monomeric dyes. The percentage dyebath exhaustion and fixation on fiber have been found to be from good to very good. The dyeing of monomeric dyes showed very good color fastness properties and their corresponding polymeric dyes showed excellent fastness to light, washing, perspiration, solvent resistance, and sublimation.

Thiadiazole-Based Monomeric and Polymeric Dyes for Cellulose Triacetate Fiber

A series of monomeric dyes was prepared by diazotization of 2-amino-5-mercapto-1,3,4-thiadiazole and coupled with various N-arylmaleimides. The polymeric dyes were prepared by free radical polymerization of monomeric dyes and characterized by IR, intrinsic viscosity, molecular weight by vapor pressure osmometry, thermogravimetry analysis, and elemental analysis. The monomeric dyes were also characterized by elemental analysis and IR spectra. The purity of all the dyes were checked by thin layer chromatography and by application on cellulose triacetate fiber as disperse dyes. All the dyes were found to give various color shades with good-to-very good depth and levelness on fiber. The percentage dyebath exhaustion and fixation on fiber was found to be good-to-very good. The dyeing of monomeric dyes showed very good fastness properties, and their corresponding polymeric dyes showed excellent fastness to light, washing, perspiration, solvent resistance, and sublimation.

Synthesis of 2-Azobenzo[b]thiophene Derivatives and Their Application on Nylon Fibre

A series of novel monoazo disperse dyes derived from the coupling of diazotized 2-aminobenzo[b]thiophene derivatives with N-arylmaleimides is described. The monoazo disperse dyes applied to nylon fabric and their dyeing performance has been assessed. These dyes have been found to give light yellow to reddish pink color shades with very good depth and levelness on nylon fabric. The dyed fabric shows moderate light fastness and excellent washing, rubbing, perspiration, and sublimation fastness. The percentage dyebath exhaustion on nylon fabric has been found to be good and acceptable.