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Article
Publication date: 2 June 2021

Jiaxue Yu, Jinglin Tang, Xiaoyan Wang, Jinmei Du, Changhai Xu and Shansheng Zhang

This paper aims to synthesize benzothiazole-azo disperse dyes which can be applied not only for dyeing and alkaline reduction of polyester fabric in one bath, but also for…

Abstract

Purpose

This paper aims to synthesize benzothiazole-azo disperse dyes which can be applied not only for dyeing and alkaline reduction of polyester fabric in one bath, but also for dyeing and peroxide bleaching of cotton/polyester blend fabric in one bath.

Design/methodology/approach

The synthesized benzothiazole-azo disperse dyes were confirmed by proton nuclear magnetic resonance (1H-NMR) spectroscopy, mass spectroscopy (MS) and UV–visible spectrophotometry. The performance on resistance to alkaline treatment and peroxide bleaching was tested by measuring the color strength of polyester fabric dyed with the synthesized benzothiazole-azo disperse dyes under high-temperature and high-pressure conditions.

Findings

Increasing the electron-withdrawing ability of the substituents in the diazo component and the electron-donating ability of the substituents in the coupling component resulted in a significant bathochromic shift of the maximum absorption wavelength. Except that the disperse dyes synthesized from the coupling components containing the hydroxyethyl group were unstable in alkaline solution, all others exhibited high resistance to alkaline treatment and peroxide bleaching.

Practical implications

The synthesized benzothiazole-azo disperse dyes provide the opportunities to combine dyeing and alkaline reduction of polyester fabric into one bath, and combine dyeing and peroxide bleaching of cotton/polyester blend fabric into one bath.

Originality/value

The synthesized benzothiazole-azo disperse dyes help to establish short processes of polyester and polyester/cotton blend fabrics so as to reduce energy consumption and raise production efficiency.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 13 November 2007

M.A. El‐Kashouti, G.H. Elgemeie, M.M El‐Molla, H.S. El‐Sayad and K.A.E. Ahmed

To synthesize some new heterocyclic disperse azo dyes and their utilization in textile printing.

Abstract

Purpose

To synthesize some new heterocyclic disperse azo dyes and their utilization in textile printing.

Design/methodology/approach

To prepare 1‐cayno‐1‐substituted aryl azo‐2‐methyl benzothiazole by the reaction of 2‐aminothiophenol with malononitrile and the end product coupled with different diazonium salts. The prepared dyestuffs are established using element analysis, IR measurements, 1H‐NMR and Mass spectra. Printing pastes containing the prepared dyestuffs and a thickener were used for printing polyester and/or nylon 6 using either transfer printing or traditional printing.

Findings

New selected arylazo cyanomethyl benzothiazole dyes were obtained from the reaction of diazotized aniline derivatives with 2‐cyanomethyl benzothiazole as a coupling component. The suitability of the prepared dyestuffs for either heat transfer printing or traditional printing on polyester and nylon 6 fabrics has been investigated. The prints obtained from dyes containing non polar groups which have sublimation properties possess high colour strength as well as good overall fastness properties if compared to those obtained using dyes containing polar groups.

Research limitations/implications

The new heterocyclic disperse azo dyes were prepared from 2‐cyanomethylbenzothiazole and were utilized in preparing pastes for textile printing to print polyester and nylon 6 fabrics. In addition, the variation in substituents on the synthesized dyes could also be studied.

Practical implications

The method of synthesis of the new dyestuffs provides a simple and practical solution to prepare some new heterocyclic disperse azo dyes with low molecular weight, suitable for sublimation in heat transfer printing methods.

Originality/value

The methods for synthesis of the new heterocyclic disperse azo dyes are simple. These dyestuffs could be used in textile printing of polyester and nylon 6 on an industrial scale.

Details

Pigment & Resin Technology, vol. 36 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 12 September 2008

H.Z. Shams, M.H. Helal, I.M. Samir and R.M. Mohareb

The purpose of this paper is to evaluate the dyeing performance of newly designed and synthesised azo dye systems based on polyfunctionally substituted oxopyridine core…

Abstract

Purpose

The purpose of this paper is to evaluate the dyeing performance of newly designed and synthesised azo dye systems based on polyfunctionally substituted oxopyridine core for improved dyeing when applied to synthetic fibres.

Design/methodology/approach

For improved dyeing qualities, various azo dye systems were synthesised based on polyfunctionally substituted oxopyridine core as the coupling component. The heterocyclic moiety was coupled with diazotized aromatic amines or diazotized tetrahydrobenzothiophenes to afford the respective azo or hydrazono systems. Other counterparts were obtained via treatment with different reagents. The structure of the novel systems was elucidated based on elemental analysis and spectral data. Dyeing performance, electronic spectra and optical properties were characterised based on UV and K/S measurements. Fastness properties were also evaluated.

Findings

The novel systems were designed so that the functionalities located on the heterocyclic core afforded structure modification that led not only to good dispersion but also to improved adherence on the fibre. The sites of location led to construction of a resonating system with higher electron mobility and higher absorption maxima.

Research limitations/implications

The azo dyes, used in the present context were synthesised via a step‐wise pathway leading to different systems of dyes. In addition, the variations in substituents and sites of location on the heterocyclic core could also be studied.

Practical implications

The novel azo dye systems based on polyfunctionally substituted oxopyridine core provide a simple practical access to a series of azo dyes with improved dyeing properties. The availability of starting materials, the simplicity and efficiency for production in good yields and high‐purity can lead to valuable achievements for commercial production.

Originality/value

The designed and synthesised azo dye systems could find numerous applications as disperse dyes in the fields of dyeing, printing and surface coating. Moreover, the systems could find applications as reactive dyes for wool, silk and cellulosic fibres.

Details

Pigment & Resin Technology, vol. 37 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 18 September 2007

M.H. Helal, G.H. Elgemeie and D.M. Masoud

This paper aims to synthesize some new heterocyclic disperse azo dyes and their application in dyeing of polyester and polyamide fabrics.

Abstract

Purpose

This paper aims to synthesize some new heterocyclic disperse azo dyes and their application in dyeing of polyester and polyamide fabrics.

Design/methodology/approach

Pyrazolopyrimidine derivatives containing arylazo function by the reaction of 3,5‐ diaminopyrazole with ketene dithioacetals were prepared. The prepared dyestuffs are established using elemental analysis, IR measurements, 1H‐NMR and Mass spectra.

Findings

2,5‐diamino‐3‐arylazo‐N‐aryl‐6‐carboxamide‐7‐methylthio‐pyrazolo[1,5‐a]pyrimidine have been synthesized by the simple method. The dyed fabrics have a very good (4‐5) to excellent (5) results toward washing, perspiration, and rubbing fastness properties. The dyes are superior in terms of preparation and fastness properties.

Research limitations/implications

The disperse azo dyes used in this paper were synthesized via a step‐wise pathway leading to the new azo dyes. In addition, the variations in substituents and sites of location on the heterocyclic moiety could also be studied.

Practical implications

The new azo dye systems based on substituted pyrazolopyrimidine provided a series of azo dyes with improved dyeing properties. The dyes are superior in terms of yield, purity, colour strength, and fastness properties and will lead to valuable achievements for commercial production.

Originality/value

The synthesized disperse azo dyes are superior in terms of preparation, yield, purity, and fastness properties.

Details

Pigment & Resin Technology, vol. 36 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 7 November 2008

M.H. Helal, G.H. Elgemeie and D.M. Masoud

This paper's aim is to evaluate the dyeing performance of newly designed azo dye system based on thiazole substituted for improved dyeing when applied to synthetic fibres.

Abstract

Purpose

This paper's aim is to evaluate the dyeing performance of newly designed azo dye system based on thiazole substituted for improved dyeing when applied to synthetic fibres.

Design/methodology/approach

For improved dyeing qualities, various azo dye systems were synthesised based on polyfunctionally substituted thiazole as the coupling component. The heterocyclic moiety was coupled with diazotised aromatic amines to afford the respective azo or hydrazono systems. The structure of the novel systems was elucidated based on elemental analysis and spectral data. Dyeing performance, electronic spectra and optical properties were characterised based on UV and K/S measurements. Fastness properties were evaluated.

Findings

The novel systems were designed so that the functionalities located on the heterocyclic ring afforded structure modification that led not only to good dispersion but also to improved adherence on the fibre. The location of the sites led to constructing a resonating system with higher electron mobility and higher absorption maxima.

Research limitations/implications

The azo dyes, used in the present context were synthesised via a step‐wise pathway leading to new dyes. In addition, the variations in substituents and location of sites on the heterocyclic core could also be studied.

Practical implications

The novel azo dye systems based on polyfunctionally substituted thiazole provided a simple practical access to a series of azo dyes with improved dyeing properties. The availability of starting materials, the simplicity and efficiency to production in good yields and high purity lead to valuable achievements for commercial production.

Originality/value

The designed azo dye systems could find numerous applications as disperse dyes in the fields of dyeing, printing and surface coating. Moreover, the systems can find applications as reactive dyes for wool, silk and cellulosic fibres.

Details

Pigment & Resin Technology, vol. 37 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 1 August 2001

Galal H. Elgemeie, Maher H. Helal and Heba M. El‐Sayed

The synthesis and chemistry of nitrogen heterocyclic azo compounds have been extensively studied. Many derivatives of this type were proved to be excellent dyes. Presents…

Abstract

The synthesis and chemistry of nitrogen heterocyclic azo compounds have been extensively studied. Many derivatives of this type were proved to be excellent dyes. Presents a systematic and comprehensive survey of all recently synthesised nitrogen heterocyclic azo dyes according to dyeing methods.

Details

Pigment & Resin Technology, vol. 30 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 1 April 1994

Y.M. ElKholy and S.A. Abd El‐Hafiz

In recent years heterocyclic azo dyes have been the subject of an intense research by dye manufacturers. Even so, little has been devoted to technical properties, so we…

Abstract

In recent years heterocyclic azo dyes have been the subject of an intense research by dye manufacturers. Even so, little has been devoted to technical properties, so we have recently directed our research activities towards studying the ability of thiazole azo and hydrazono disperse dyes for dyeing of polyester and cellulose acetate.

Details

Pigment & Resin Technology, vol. 23 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 5 September 2016

Hatem Gaffer, Mounir Salem and Magda Marzouk

The present study aims to focus on the possibility of developing new eco-friendly azo dyes with good colouristic application properties, exhibiting biological and…

Abstract

Purpose

The present study aims to focus on the possibility of developing new eco-friendly azo dyes with good colouristic application properties, exhibiting biological and pharmacological activities.

Design/methodology/approach

Coupling of 4-hydroxycoumarin with a variety of aromatic diazonium salts of 2-aminothiazole, 2-aminobenzothiazole, 4-aminoantipyrine, 4-aminoacetophenone, adenine sulphate, a-naphthylamine and sulphadimidine to produce novel azo dyes. The compounds were fully characterised using spectroscopic and analytical methods. All of the compounds were tested for their antimicrobial, anticancer and antioxidant activities. The prepared dyestuffs were dyed on polyester fabrics and subsequently their dyeing properties, light, washing, perspiration, rubbing and sublimation fastness were determined.

Findings

The spectroscopic data of the synthesised compounds have provided decisive evidence that such compounds exist in the solid state as the azo-dike to form C and in solution in equilibrium tautomer forms A, B and D. The prepared dyestuffs are suitable for either heat transfer printing or traditional printing on polyester and nylon 6 fabrics. The prints obtained from the dyes possess high colour strength, as well as good overall fastness properties. Also the synthesised compounds exhibit good biological and pharmacology activity.

Research limitations/implications

Synthesis of these seven azo dyes for textile dyeing had never been reported previously.

Practical implications

The dyestuffs derived from 4-hydroxycoumarin are reasonable azo disperse dyestuffs giving good all round fastness properties on polyester fabrics.

Social implications

Production of less expensive and new eco-friendly dyes exhibit antimicrobial and anticancer activity.

Originality/value

It provided a potentially simple way to synthesize novel coumarin azo-dyes exhibit good biological and pharmacology activity and also exhibit good overall fastness properties.

Details

Pigment & Resin Technology, vol. 45 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 4 January 2016

A.A. Fadda and N.S. Abbas

– The purpose of this paper is to discuss the synthesis of new azo disperse dyes containing pyridine ring for dyeing acetate polyester and other fibres.

Abstract

Purpose

The purpose of this paper is to discuss the synthesis of new azo disperse dyes containing pyridine ring for dyeing acetate polyester and other fibres.

Design/methodology/approach

Cycloaddition reaction of 3-formylchromone (Compound 1) with ethyl vinyl ether (Compound 2) afforded 3-ethoxy-4,4a-dihyro-3H,10H-pyrano[4,3-b]chromen-10-one (Compound 3). Reaction of 3 with aqueous ammonium sulphite in ethanol furnishes 3-(2-hydroxybenzoyl)pyridine (Compound 5). Compound 5 was fully characterised by spectroscopic techniques. Ten arylazo derivatives of Compound 6 have been prepared for use as dyestuffs. The effect of the nature and orientation of substituents in the diazonium component on the colour of azo dyes is discussed. Dyeing performance of the dyes on different fibres has also been assessed.

Findings

Most of the dyes showed good affinity to polyester fibres. On the other hand, polyacrylic fibres were only stained to weak shades.

Originality/value

No details regarding the synthesis and dyeing performance of such dyes are reported before in the literature.

Details

Pigment & Resin Technology, vol. 45 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 11 January 2008

M.H. Helal, G.H. Elgemeie, M.A. El‐kashouti and K.A. El‐zaher Ahmed

The purpose of this paper is to synthesise new heterocyclic disperse azo dyes based on benzothiazapine moiety and their printability on synthetic fabrics.

Abstract

Purpose

The purpose of this paper is to synthesise new heterocyclic disperse azo dyes based on benzothiazapine moiety and their printability on synthetic fabrics.

Design/methodology/approach

Ethyl cyanoacetate was refluxed with aniline derivatives for 3 h to form cyanoacetanilides which coupled with different diazonium salts. The products obtained were cyclised with 2‐amino thiophenol to form arylazo benzothiazapine derivatives. The structures of the new dyes were characterised by micro‐analysis as well as IR, 1H NMR and 13C NMR. Printing pastes containing the dyestuffs prepared and thickened with sodium alginate were used for printing synthetic fabrics using either transfer printing or traditional screen printing.

Findings

New heterocyclic monoazo dyes derived from benzothiazabine moiety were obtained by the coupling of diazotised aniline derivatives with ethylcyanoacetate anilides followed by cyclisation with 2‐amino thiophenol. The use of synthesised dyes for transfer‐ or screen‐printing polyester and nylon 6 fabrics has been studied. The synthesised dyes which contain electron withdrawing substituents (NO2) in the phenyl ring attached to the azo groups and electron‐donating (OCH3) group on the other phenyl ring exert a bathochromic effect.

Research limitations/implications

Synthesis of azo dyes containing benzothiazapine moiety has never been reported in textile printing.

Practical implications

Production of simple and less costly dyes.

Originality/value

Synthesis of aryl azo benzothiazapine dyes by a simple method and application in printing of synthetic fabrics.

Details

Pigment & Resin Technology, vol. 37 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

1 – 10 of 108