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The purpose of this study is to check the effectivity of plasma in the natural dyeing of polyester fabric using four natural dyes – Turkey red, Lac, Turmeric and Catechu using plasma and alum mordant. The surface modification on the polyester fabric by plasma along with the use of benign mordant alum is studied. The enhancement of dyeability in polyester fabric with natural dyes is the main focus. Due to surface modification, the wettability increases, which leads to better dye uptake. Better dye uptake and better dye adherence are the main objectives.

Plasma-mediated natural dyeing is the main design of this research work. The effect of plasma treatment on surface modification of synthetic fabric polyester and its subsequent effects on their dyeing with different natural dyes, namely, Turkey red, Lac, Turmeric and Catechu are studied. The dyeability was further enhanced by the use of alum as mordant. The main focus is on the betterment of natural dyeing of polyester fabric using sustainable natural dyes resources for dyeing and to reduce wastewater contamination from the usage of toxic additive chemicals for cleaner production.

Plasma-mediated and alum-mordanted dyeing method facilitated very good dyeability of all the four natural dyes, namely, Turkey red, Lac, Turmeric and Catechu. Color strength (K/S) values and fastness properties of plasma-treated samples were far better than untreated samples. The synergistic effect of plasma and alum mordanting has made natural dyeing of polyester very easy with very good fastness results. Natural dyeing of polyester after 2 min of plasma treatment showed excellent and desirable results. The process is also easy to be adapted by industries.

As polyester is hydrophobic, natural dyeing of polyester fabric is not very easy, but with plasma-mediated natural dyeing, it becomes a very facile dyeing method; thus, there are no limitations. Use of plasma has reduced the need for any chemical additives which are usually added during the dyeing process.

This process of natural dyeing of polyester fabric can be scaled up to industrial dyeing with natural dyes. Plasma pretreatment of the fabric followed by premordanting with alum has facilitated the natural dyeing well.

Use of plasma in place of chemical modifiers can be a green and environmentally friendly approach for sustainable coloration of polyester fabric, providing a clean wet processing for textiles dyeing.

The synergistic effect of plasma-mediated and alum-mordanted natural dyeing of polyester has not been attempted by any researcher. To the best of the authors’ knowledge, this is for the first time that pretreatment with atmospheric plasma followed by alum mordanting of polyester fabric has shown very good dye uptake and fastness properties as the dye molecules could penetrate well after 2 min of the plasma treatment.

Textile industry is considered to be one of the largest consumers of water. There needs to be an alternative for water in textile wet processing. Solvent dyeing can be an approach to replace the use of water in dyeing for water conservation.

In this study, the dyeing of polyester was carried out using conventional and solvent dyeing methods. The solvent used was non-aqueous, deep eutectic solvent (DES) prepared using choline chloride and urea. Dyeing parameters such as time, temperature and pH were optimized for a concentration of dye using the solvent and were compared with the conventional dyeing.

The prepared solvent was characterized in terms of Fourier-transform infrared resonance and ¹H and ¹³C nuclear magnetic resonance to analyze the reaction between choline chloride and urea. Dyeing performance in terms of K/S and fastness properties of dyed fabrics were evaluated and found to be at par against conventional dyeing.

Use of DES as a dyeing medium is a novel approach in the textile industry.

The paper aims to the preparation of novel disperse dye based on azo salicylaldehyde derivatives TF-A [2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde] and full evaluation of their use as disperse dye TF-ASC [bis 2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde Schiff base with 4,4'-methylenedianiline] for dyeing polyester fabric at various conditions.

The dispersed dye was synthesized via Schiff base condensation in the presence of ceric ammonium nitrate cerium ammonium nitrate 10 mmole% as an eco-friendly catalyst at room temperature. The chemical structure of the prepared dye was characterized via elemental analysis, Fourier-transform infrared spectroscopy, 1H- and 13 C-NMR spectroscopic analysis tools. This study thoroughly examined the dyeing of disperse dye TF-ASC on polyester at various conditions. The characteristics of dyed polyester fabric were measured by colour measurements, as well as light, washing, crock fastness and finally, colour strength. The discrete fourier transform (DFT) theoretical studies, including E_HOMO, E_LUMO and optimized geometrical structure, were assumed and discussed in detail.

The results showed that the synthesized organic dye TF-ASC was highly functional and appropriate for this kind of dyeing method. The dyeing fabrics obtained from disperse dye TF-ASC, properties possess high colour strength as well as good overall fastness properties. These dyes had a high affinity for polyester fabric, with just a tiny change in dye affinity when the pH was changed, even under alkaline circumstances. The dye levelness and shade depth of the colour results were good, and there were a variety of hues from light brownish yellow to deep brownish yellow. The results obtained from DFT computational studies such as E_HOMO, E_LUMO, optimized structure, diploe moment µ and electrophilicity index deduced that prepared organic dye TF-ASC is more applicable as a dispersed dye.

This research is significant because it provides a new dye for dyeing polyethylene terephthalate fibres with exceptional brightness and levelness; the method of preparation is a useful pathway due to its being known as a green chemistry method.

This study aims to show the dyeing behaviour of polyester fabrics using four novel heterocyclic disperse dyes.

The four dyes were synthesized based on 5, 5'-(1, 4-phenylene) bis (1, 3, 4-thiadiazol-2-amine) as a diazonium compound. The UV/Vis absorption spectroscopic data of these disperse dyes while dyeing polyester fabrics were investigated. Following this, the dyeing properties of these dyes on polyester fabrics were investigated under acid condition.

The results showed that increasing the dyeing temperature from 80°C to 100°C led to an increase in dye uptake for all dyes, but further increases of the temperature to 130°C led to higher dye uptake for dye 3 as the dye exhaustion increased by about 50% from 55.9% to 91.4%.

This study is important as it introduces new dyes for the dyeing of polyethylene terephthalate (PET) fibres with colours that range from yellowish orange to bluish yellow and scarlet red and all with excellent brightness, levelness and depth of shade.

This study aims to synthesize new disperse dyes based on novel pyrazolyl quinolinone derivatives EQ1 and EQ2 and evaluate their characteristics after dyeing them on a polyester fabric.

New dispersed dyes based on pyrazolyl quinolinone derivatives were prepared and confirmed by different analyses, such as infrared spectroscopy, elemental microanalysis and nuclear magnetic resonance spectroscopy. They were dyed on a polyester fabric. The characteristics of dyed polyester were determined by color measurements such as a*, b*, L*, C*, E, Ho, R% and color strength. The electronic structures of EQ1 and EQ2 in gaseous state were investigated using density functional theory/B3LYP/6-311++G (d, p) level of theory.

The suitability of the prepared dyestuffs for dyeing on polyester fabrics has been investigated. The study was concerned with comparing the contrasting depth of shade and levelness. The study was concerned mainly with dye uptake and color measurements at two different temperatures. The results showed that the exhaustion values of dyes inside the polyester at 130°C were higher than those obtained at conventional dyeing temperature (100°C). The exhaustion values of EQ2 were greater than those of EQ1 at 130°C with 2.2%, while the brightness of EQ2 was higher than that of EQ1 at the two investigated temperatures. The results of molecular orbital calculations show that the studied compounds are planar. In addition, the ionization potential of EQ1 was lower than that of EQ2. The results of the theoretical study helped in understanding the dyeing behavior of the investigated azo dyes.

The prepared disperse dyes based on pyrazolyl quinolinone derivatives could be used in textile dyeing of polyester on an industrial scale.

This paper aims to develop a novel protocol for the synthesis of disperse dyes derived by a triple cascade reaction with lawsone in presence of Zn acetate as a catalyst. The developed novel scaffolds have efficient dyeing properties on nylon and polyester fibers.

This report demonstrates an effectual triple cascade protocol for the synthesis of novel disperse dyes derived from various polynuclear carbaldehyde, urea and lawsone. The Zn acetate was found to be an effective catalyst for this reaction. Their dyeing performance has been studied on nylon and polyester fabrics. The wash fastness, sublimation fastness, color assessment, determination of percentage exhaustion and fixation properties were applied to both the dyed fabrics.

The obtained results indicate that the Zn acetate is an efficient catalyst for the developed triple cascade protocol. The prepared novel disperse dye greatly impacted their dyeing properties on nylon and polyester fibers. They have shown brilliant shades, higher affinity, adsorption capacity, superior tinctorial strength than the lawsone. The percentage exhaustion value, fixation value, color strength (K/s) value, washing and sublimation fastness properties have been found very well in all dyed nylon samples compared to polyester samples. These results discloses that these disperses dyes are very useful to the growing importance of nylon and polyester fibers.

The present protocol synthesizes the racemic mixture of the prepared molecules.

Developed protocol can be used for various other triple cascade processes. Also these molecules can be used for dyeing of other fabrics.

With the help of commercialization of prepared molecules, it may provide the better alternative of the current disperse dyes. This may affect the various segments of society.

This report represents a novel protocol for the synthesis of modified novel disperse dyes with an efficient dyeing properties on nylon and polyester fibers.

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.

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.

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.

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.

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.

The purpose of this paper is to highlight the one bath dyeing method for polyester/wool (PES/Wo) blend fabric with two different semi-synthetic azo dyes developed by chemically modifying the outer skin of Allium cepa.

Chemical modification is the most heartening way to impart improved properties to natural sources. Two different primary amines were coupled with the Allium cepa skin extract by a diazo coupling reaction. Synthesised dyes were characterized for their percentage yield, solubility tests, melting point, particle size analysis as well as FTIR spectroscopy and UV-Visible analysis. One bath dyeing methodology was used for application of synthesized dyes on PES/Wo blend fabric. Dyeing was performed at boil without any additional auxiliary and further percentage dye exhaustion was evaluated.

Dyeing yielded solid shade on PES/Wo blend fabric with satisfactory levelness in dyeing. The efficacy of synthesized dyes for dyeing of PES/Wo fabric was studied by wash, rub, light and sublimation fastness properties, which are in good agreement with commercial requirements. The antimicrobial activity of the synthesized dyes shows excellent activity in dye powder form (AATCC 147 test method) as well as on dyed fabrics (AATCC 100 test method).

Present research work is a first successful attempt to dye PES/Wo blend fabric with semi-synthetic azo dyes in single bath at boil. Such approach facilitates minimum consumption of energy, cost and time.

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.

This study aims to the synthesis of some novel 4-arylazo-3-hydroxythiophene analogues containing sulphapyridine and sulphathiazole dyestuffs and studying their application in dyeing polyester fabrics and rendering their antibacterial efficacy.

Simultaneous dyeing and antibacterial finishing for polyester fabric using a new antibacterial disperse dye having a modified chemical structure to thiophene dyes were studied. Construction of the thiophene dyes was carried out by diazo-coupling of diazotized sulphonamide-containing heterocyclic rings sulphapyridine and sulphathiazole with ethyl α-phenylthiocarbamoyl-acetoacetate followed by cyclizing the produced 2-arylazo-thioacetanilide with various α-halogenated reagents. All newly synthesized compounds were characterized by elemental analysis and extensive study of their spectral data (IR and ¹H-NMR). The dyeing characteristics of these thiophene dyestuffs were evaluated at optimum conditions. Antibacterial activities of the obtained thiophene dyes were studied against some Gram-positive and Gram-negative bacteria.

The synthesized thiophene-containing sulphonamides dyes were applied on polyester fabric. The modified dyes exhibited a good fastness properties and antibacterial efficacy against some Gram-positive and Gram-negative bacteria. Synthesized dyes showed higher antibacterial potency than the reference standard drug.

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

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

Thiophene dyes are used for dyeing polyester fabrics with brilliant colour and good fastness properties. The presence of sulphonamides moieties increase their fastness properties and elevate their antibacterial properties. Moreover, they can be used as antimicrobial finish due to their bactericidal properties on dyed textiles. This work afforded a new thiophene colorant that can be used in many different uses like polyester packing, thread Surgery, blends and other uses in medical textile.