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A new series of the title pyrazole azo dye systems has been synthesized. The new dyes are applied on nylon and cellulose acetate fibers to give dyed fabrics with excellent properties of colour intensity and fastness properties. The physical and spectral data of the investigated dyes are illustrated. The shifts of ultraviolet‐visible absorption maxima affected by the structural configuration of the pyrazole dye systems are investigated. The structural effects of the polyfunctionally substituted pyrazole dye systems on the intensity of colour and fastness properties of the dyed fabrics are discussed. The data of these studies are listed. The colour shades of the synthesized dyes on nylon and acetate fabrics are indicated.

This work aims to synthesize a series of novel acyclic and/or heterocyclic systems, as precursors for dyes with potential antimicrobial activity that could be used for simultaneous dyeing and antimicrobial textile finishing. Thus, a series of novel pyridine, thiophene and pyrazolo[3,4-b]pyridine derivatives were synthesized, and their antimicrobial and textile finishing properties were studied and evaluated.

The synthesis, structure elucidation and antimicrobial activities of the newly synthesized compounds based on 4,4-dicyano-3-phenyl-but-3-enoic acid phenylamide (1) were demonstrated. The minimal inhibitory concentration in μg/mL of the compounds showed significant antimicrobial activity against most of the tested organisms. On the other hand, their spectral characteristics and fastness properties were measured and evaluated. Antimicrobial activities of the dyed fabrics in terms of inhibition zones (mm) were measured and evaluated.

A series of novel heterocyclic compounds (Schemes 1-3) were synthesized based on starting material (1). Compounds (1), 2, 4a, 8a and 9c exhibited comparable or even higher antibacterial activities than the selected standards (ampicillin), while compounds 2, 3c, 3d, 4a and 8b revealed higher antifungal activities than the selected standard (cycloheximide). On the other hand, some dyes showed high antimicrobial evaluation on the dyed fabrics (nylon 66, acetate and polyester) expressed as size (mm) of inhibition zones (Tables I-IV).

Results revealed that many hydrazo and azo derivatives were synthesized from some pyridines and thiophenes. The antimicrobial evaluation and textile finishing of the newly synthesized products revealed significant and potent values of antimicrobial activity.

All the synthesized compounds were novel and most of them exhibited higher antimicrobial activities than the selected standards antibiotics, thus are valuable for simultaneous dyeing and antimicrobial functional finishing of textile fabrics.

The purpose of this paper is to evaluate the efficiency of modifying reactive azo dyes using pyrazolo[1,2‐a]pyrazole fused systems as the chromophoric moiety which could satisfy many and varied criteria drawn from economic, synthetic, physicochemical and fastness properties.

Six novel heterocyclic disazo reactive dyes were prepared, containing monofunctional sulphatoethylsulphone (SES) and hetero‐bifunctional monochlorotriazine (MCT)/SES reactive groups. Dyes intermediates based on 4‐arylazo‐1,5‐dioxopyrazolo[1,2‐a]pyrazole chromophoric moieties are initially synthesised and coupled with two different diazonium salts having the aforementioned reactive groups, thus yielding the new target reactive dyes. The synthesised dyes are applied to cotton, wool and silk fabrics under the typical exhaust dyeing conditions and their dyeing properties were investigated.

The results assessed for dyeing indicate high‐quality dyeing properties. However, the heterobifunctional MCT/SES dyes showed higher exhaustion and fixation values, colour yields and fastness properties than those of the monofunctional SES dyes.

The method developed provided a simple and practical procedure for producing fused pyrazolo[1,2‐a]pyrazole disazo chromophoric systems that afford valuable reactive dyes. In addition, the dyes intermediates based on 4‐arylazo‐1,5‐dioxopyrazolo[1,2‐a]pyrazole as well as their disazo counterparts could be applied as acid dyes to wool and silk.

The method for producing novel disazo reactive dyes could find numerous applications for affording a variety of reactive dyes with different binding linkages and structural reactivity. These could be valuable as reactive dyes with different colour shades.

Three series of azo dye systems are considered, namely, 5‐oxo‐2‐pyrazoline azo dye systems 9 a‐d,1‐oxo‐pyrazolo pyrazole azo dye systems 10 a, b, c, e, 11 a, b, c, e, 12 a, b, c, e, 13 a‐d and 6‐oxo‐pyranopyrzole azo dye systems 14 a‐d. The shifts of ultraviolet‐visible absorption maxima affected by the structural configuration of the pyrazole dye systems are investigated. The structural effects of the polyfunctionally substituted pyrazole dye systems on the intensity of colour and fastness properties of the dyed fabrics are also discussed. The data of these studies are listed. Colour shades of the synthesized dyes on nylon and acetate fabrics are indicated.

A new series of polyfunctionally substituted pyridine azo‐ and hydrazono dyes suitable for screen printing of polyester, cotton and polyester/cotton blend fibres have been synthesised. The prints are characterised by high depth of colour and good fastness to light and wet processings. Proofs of structure of the synthesised compounds based on microanalytical and spectroscopic data are given and discussed. The effect of substituents on the electronic absorption spectra and on the dye/fibre binding mechanism has been studied.

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.

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.

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.

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.

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.

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.

The purpose of this paper is to synthesise, characterise and find out properties of some new bifunctional reactive azo dyes using pyrazolo[1,2‐a]pyrazole 3‐carboxylic acid fused systems as the chromophoric moiety, bearing good colour strength, lightfastness, and other favourable properties.

The dyes are synthesised by diazotisation, coupling and cyclisation reactions. Firstly, synthesised 4‐arylazo‐1,5‐dioxopyrazolo[1,2‐a]pyrazole 3‐carboxylic acid chromophoric moieties and coupled with diazonium salts having the aforementioned reactive groups, thus yielding the new target reactive. The synthesised dyes were applied to cotton and wool fabrics under the typical exhaust dyeing conditions and their dyeing properties were investigated. The structures of these dyes are characterised and confirmed by melting point, elemental analysis, infrared, ultraviolet‐visible spectroscopy (UV/VIS) and nuclear magnetic resonance (1H‐NMR) data.

The wavelength of maximum absorptions, molar extinction coefficients are strongly dependent on the electron donating ability of the substituents on the coupling moiety. The absorption bands of these dyes move towards longer wavelength as the polarity of the solvents and electron density of substituents on the coupling moiety increase. The dyes applied on cotton and wool showed higher exhaustion and fixation values, colour yields and fastness properties.

The method developed provided a simple producing fused pyrazolo[1,2‐a]pyrazole disazo chromophoric systems based on 4‐arylazo‐1,5‐dioxopyrazolo[1,2‐a]pyrazole 3‐carboxylic acid as well as reactive dyes applied on wool and cotton dyes.

In this paper, three series of pyrazolo[1,2‐a]pyrazole derivatives dyes are synthesised and characterised. They have not been registered in the literature previously.

A new series of printing inks that satisfy non‐absorbent substrates, namely, metals and metal foils has been formulated. The suggested ink formulations are well adapted for the Lithographic and Flexographic Printing Processes. The inks are subjected to different testings and controllings to fulfill the requirements of printers in the graphic trade.

The presence of heavy metals in milk causes many acute and chronic physiological dysfunctions in human organs. The present study aims to investigate the heavy metals in cow's and buffalo's milk of two major cities, Karachi and Gujranwala, Pakistan to estimate metal intake by humans from this source.

In total, 48 milk samples from 2 cities were drawn from animals' udder to avoid contamination. Each sample was digested with nitric acid at 105 ^oC (degree Celsius) on a pre-heated electric hot plate to investigate the metals by atomic absorption spectroscopy (flame type). Air-acetylene technique analyzed chromium, cadmium and lead, and the hydride method analyzed arsenic in the milk samples.

The results revealed the highest mean lead concentration (19.65 ± 43.86 ppb) in the milk samples, followed by chromium (2.10 ± 2.33 ppb) and arsenic (0.48 ± 0.73 ppb). Cadmium was not detected in any sample, assuming cadmium's occurrence was below the detection level. The concentrations of all the metals in the samples of the two cities do not differ statistically. Lead concentrations in the buffalo's milk were higher than in cow's milk (p < 0.05). However, the concentrations of arsenic and chromium between buffalo's and cow's milk do not differ statistically. The present study reveals a lower level of metals in the milk than those conducted elsewhere. The mean concentrations of all the metals met the World Health Organization's (WHO) safety guidelines (1993).

Although cadmium causes toxicity in the human body, cadmium could not be measured because cadmium's concentration was below the detection level, which is 1 ppb.

This study will help reduce the toxic metals in our environment, and the sources of heavy metals, particularly from the industrial sector could be identified. The feed and water consumed by the milking animals could be carefully used for feeding them.

This study will help reduce the diseases and malfunction of human organs and organ systems since these heavy metals cause toxicity and carcinogenicity in humans. Arsenic and chromium cause cancer while lead causes encephalopathy (a brain disease).

The study reports heavy metal concentrations in the two attributes of four independent variables of raw milk samples that were scarcely reported from Pakistan.

The purpose of this paper is to synthesise, characterise and find out properties of some new bifunctional dyes bis (monochlorotriazine) using tetrahydrobenzo[b]thiophene systems as the chromophoric moiety, bearing good colour strength, lightfastness, and other favourable properties.

The novel reactive dyes were prepared, containing bis monochlorotriazine as reactive groups. The dye is synthesised by diazotization and coupling reactions. Firstly the authors synthesised the ethyl 2‐amino 4,5,6,7‐tetrahydrobenzo[b]thiophen‐3‐carboxylate chromophoric moiety compound which in turn underwent diazotization and coupling then diazotized and coupled reaction with either 1‐amino‐8‐naphthol‐3,6‐disulphonic acid (H‐acid) and or 2‐amino‐8‐naphthol‐6‐sulphonic (γ acid) to give the monoazo dye intermediates compounds. The latter products reacted with 2,4,6‐trichloro‐1,3,5‐triazine in 1:1 molar ratio afforded, via nucleophilic displacement when subjected to condensation 2,4,6‐trichloro‐1,3,5‐triazine in 1:1 molar ratio afforded via nucleophilic displacement, which reacted with 1,4‐phenylenediamine in 2:1 molar ratio to give reaction with the 1,4‐phenylenediamine in 2:1 molar ratio, the bisazobifunctional bismonochlorotriazine reactive dyes.bisazo bifunctional bismonochlorotriazine reactive dyes thus yielding the new target reactive. The synthesised dyes were applied onto cotton fabric under the typical exhaust dyeing conditions and their dyeing properties were investigated.

The results assessed for dyeing indicate high quality dyeing properties However, the homobifunctional (bis MCT) dyes showed higher exhaustion and fixation values, colour yield and fastness properties.

The described method showed the synthesis of bis monochlorotriazines derived from the tetrahydrobenzo[b]thiophene derivative 3 followed by their application towards cotton fabric.

Social implications are to prepare new reactive dyes having higher fastness and uses for dyeing cotton which is the commonest fabric use.

In this work, the novel reactive dyes derived from the tetrahydrobenzo[b]thiophene derivative 3 were synthesized and their structures were based on the analytical and spectral data. Such a group of compounds are considered to be excellent reactive dyes with different colour shades.