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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

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

Article
Publication date: 1 April 2004

G.H. Elgemeie, M.H. Helal and H.M. El‐Sayed

Several new arylazopyrazolo[1,5‐a]pyrimidine derivatives were obtained from 4‐arylazo‐3,5‐diaminopyrazoles. The application and dyeing characteristics of the dyes synthesised were…

Abstract

Several new arylazopyrazolo[1,5‐a]pyrimidine derivatives were obtained from 4‐arylazo‐3,5‐diaminopyrazoles. The application and dyeing characteristics of the dyes synthesised were also reported.

Details

Pigment & Resin Technology, vol. 33 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 2 November 2015

G.H. Elgemeie, K.A. Ahmed, E.A. Ahmed, M.H. Helal and D.M. Masoud

The study aims to synthesise new thiophene-based dyes by an efficient method using sodium a-cyanoketene dithiolates as starting components for synthesis of tetra-substituted…

Abstract

Purpose

The study aims to synthesise new thiophene-based dyes by an efficient method using sodium a-cyanoketene dithiolates as starting components for synthesis of tetra-substituted thiophenes, which act as a coupler for the synthesised dye. The synthesised dyes are applied for printing polyamide and polyester fabrics using the screen printing technique.

Design/methodology/approach

Treatment of 1 with carbon disulfide in alkaline medium forming disodium salt 2, which act as starting point for heterocyclisation to prepare these dye stuff 7. Sodium a-cyanoketene dithiolates 2 react with two moles of phenacyl bromide derivatives, forming alkylsulfanylthiophenes which react with the diazonium salt, forming the target dyestuff. These prepared dyes are used to print polyamide and polyester fabrics by using a synthetic thickener in the printing paste using screen-printing techniques.

Findings

The structure of synthesised dyes were established and confirmed for the reaction products on the basis of their elemental analysis and spectral data (IR and 1H-NMR). The suitability of the prepared dyestuffs for screen printing on polyamide and polyester fabrics has been investigated. The prints obtained from dyes possess high colour strength as well as excellent overall fastness properties.

Research limitations/implications

The diazo coupling reaction of the starting tetra-substituted thiophene 5 with diazotised aromatic amines resulted in the formation of the corresponding dye. The synthesised dyes were utilised in preparing a paste for polyester and polyamide fabric printing. In addition, both of the variations of the substituents on the synthesised dyes and the fastness properties were also studied.

Practical implications

The synthesised dyes are superior in terms of yield, purity, colour strength and fastness properties, which lead to valuable achievements for commercial production.

Social implications

The synthesised dyes are superior for application in fabrics.

Originality/value

The synthesis for novel thiophene-based dye stuff for application in printing properties on polyester and polyamide fabrics and study their fastness properties.

Article
Publication date: 5 May 2015

G.H. Elgemeie, K.A. Ahmed, E.A. Ahmed, M.H. Helal and D.M. Masoud

The purpose of this paper is to synthesize some novel 2-amino-6,6-dimethyl-9-phenyl-3-(phenyldiazenyl)-6,7-dihydropyrazolo-[5,1-b]quinazolin-8(5H)-one derivatives by…

Abstract

Purpose

The purpose of this paper is to synthesize some novel 2-amino-6,6-dimethyl-9-phenyl-3-(phenyldiazenyl)-6,7-dihydropyrazolo-[5,1-b]quinazolin-8(5H)-one derivatives by multi-component one-pot reaction using a microwave as a new tool for green chemistry.

Design/methodology/approach

An equimolor from arylazopyrazole, 5,5-dimethyl-1,3-cyclohexanedione (dimedone) and benzaldehyde derivatives was dissolved in Dimethylformamide (DMF) to be irradiated in a microwave for 15 minutes; after completion of the reaction, as indicated by Thin layer chromatograph (TLC), the reaction mixture was poured into ice water, filtered and then crystallized with an appropriate solvent.

Findings

The structure of the synthesized dyes was established and confirmed for the reaction products on the basis of their elemental analysis and spectral data (MS, IR and 1H-NMR). These prepared dyes were used to print polyester and polyamide fabrics using synthetic thickener in the printing paste for the silk screen technique. The synthesized dyes are superior in terms of yield, purity, color strength and fastness properties and will lead to valuable achievements for commercial production.

Originality/value

An efficient method for synthesis of pyrazoloquinazolinone dyes was designed. The novel procedure features short reaction time, moderate yields and simple workup. The authors studied its application in printing polyester and polyamide fabrics.

Details

Pigment & Resin Technology, vol. 44 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 April 2003

G.H. Elgemeie, M.H. Helal and H.M. El‐Sayed

Several novel pyrazolo[1,5‐a]pyrimidine derivatives containing two arylazo functions were synthesised from 4‐arylazo‐3,5‐diaminopyrazoles. Such derivatives were used as starting…

Abstract

Several novel pyrazolo[1,5‐a]pyrimidine derivatives containing two arylazo functions were synthesised from 4‐arylazo‐3,5‐diaminopyrazoles. Such derivatives were used as starting components. The characteristics of and the application properties of the dyes synthesised from 4‐arylazo‐3,5‐diaminopyrazoles were investigated and reported.

Details

Pigment & Resin Technology, vol. 32 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

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 a…

1175

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

Article
Publication date: 1 August 2003

S.Y. Alqaradawi

The synthesis of novel cycloalkane ring‐fused arylazopyrazolo[1,5‐a]pyrimidines, using 4‐arylazo‐3‐aminopyrazol‐5‐ones as starting components, is described in this paper. The…

Abstract

The synthesis of novel cycloalkane ring‐fused arylazopyrazolo[1,5‐a]pyrimidines, using 4‐arylazo‐3‐aminopyrazol‐5‐ones as starting components, is described in this paper. The dyeing application and the dyeing characteristics of the dyes synthesised are also reported.

Details

Pigment & Resin Technology, vol. 32 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 20 March 2009

E. Abdel‐Latif, F.A. Amer, M.A. Metwally and M.E. Khalifa

The purpose of this paper is to synthesise some new 5‐arylazothiazole disperse dyes and study their application in dyeing polyester fibres.

Abstract

Purpose

The purpose of this paper is to synthesise some new 5‐arylazothiazole disperse dyes and study their application in dyeing polyester fibres.

Design/methodology/approach

A series of 5‐arylazo‐2‐(arylidenehydrazino)‐4‐substituted‐thiazole dyes were prepared by cyclocondensation of hydrazonoyl bromides with various thiosemicarbazone derivatives.

Findings

The dyed fibres exhibit very good washing, perspiration, sublimation and light fastness properties with little variation in the moderate to good rubbing fastness. The ease of preparation and the acceptable fastness properties makes these dyes particularly valuable.

Research limitations/implications

In the present paper, the synthesis of 5‐arylazo‐2‐(arylidenehydrazino)‐thiazole disperse dyes was achieved by one step pathway. In addition, the variations in substituents on the aryl and thiazole moieties could also be studied.

Practical implications

The new arylazo‐thiazole disperse dyes are superior in terms of yield, purity, colour strength, and having fastness properties of an order acceptable for commercial utilisation.

Originality/value

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

Details

Pigment & Resin Technology, vol. 38 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 June 2004

M.H. Helal

A series of azo dye systems, namely, 5‐arylazo‐pyridin‐2‐one dye systems (5a‐k), was synthesised and characterised. The effects of the structural configuration of the pyridinone…

Abstract

A series of azo dye systems, namely, 5‐arylazo‐pyridin‐2‐one dye systems (5a‐k), was synthesised and characterised. The effects of the structural configuration of the pyridinone dye systems on the shifts of the ultraviolet‐visible absorption maxima were investigated. The structural effects of the polyfunctionally substituted pyridinone dye systems on the intensity of colour and fastness properties of the dyed fabrics were also discussed.

Details

Pigment & Resin Technology, vol. 33 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

11 – 20 of 27