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This paper aims to develop a new method of protein detection in fabric using purified henna extract targeted to be used as a precautionary step by protein contact dermatitis (PCD) patients.

Henna contains lawsone, which is known for its reaction with amino acid, resulting in the formation of a highly coloured compound. Dye exhaustion test of 2 per cent purified henna extract was done on both protein and non-protein fabric, and the results were analysed using independent samples t-test to assess the significant differences of the comparison. Then, protein fabric indicator was developed by incorporating purified henna extract. It was tested for its dye ability and stability.

Protein fabrics showed a significant higher dye exhaustion (p = 0.001) in which pure silk came in first with 21.70 per cent ± 2.53, silk/rayon, 13.96 per cent ± 0.55, viscose/wool, 9.57 per cent ± 1.36, cotton/spandex, 5.89 per cent ± 0.86, linen/cotton, 5.26 per cent ± 1.29, cotton, 4.87 per cent ± 1.51, polyester/viscose, 4.69 per cent ± 1.09, linen, 4.56 per cent ± 0.86, polyester/cotton, 3.90 per cent ± 0.29 and polyester and 3.88 per cent ± 0.66. Two different forms of protein fabric indicator were developed: capsule and tablet. Both indicators showed good observable dye exhaustion and fixation results. Orange henna dye was fixed on protein fabric while non-protein fabric returned to its original colour after washing procedure. However, the tablet form showed better performance in terms of functionality and stability.

This study will help general community to better understand fibre and its constituents, especially protein where clothing is an integral part of human life because it comes in direct contact with the human skin. As PCD caused by clothing and textile is an uncommon disease, it may also help in creating awareness on how some people may develop contact dermatitis through fabric. This is because the fabric’s protein content is a causative allergen, which most people tend to overlook. For the researcher, this study helps to elucidate some critical areas in PCD for clothing and textile as this topic can be considered an understudy. There is no standard method to detect protein in fabric, especially blended fabric. Thus, a portable kit to detect protein in fabric will be developed in this study. This kit will benefit PCD patients to ease them in finding the right fabric for their skin.

Fibre reactive dyes are very popular for cellulosic garments as they are environmentally safe and having good overall fastness properties. But application of these dyes requires a very high concentration of salt. The salt released from garment dyeing increases salinity in drain water stream which has a negative impact on environmental ecology. The present work aims to eliminate the usage of salt during dyeing of cotton goods with reactive dyes.

The methodology adopted here, for the elimination of salt in cotton dyeing, was based on the principle of cationisation (to develop a positive charge) of cotton. The same was achieved by subjecting the caustic pretreated cotton fabric samples to a treatment of 1, 2 dichloroethane followed by methylamine to introduce amino groups in the cellulose structure. The treated cotton when dyed from slightly acidic bath generates positive sites due to protonation in the amino group. The reactive dyes being anionic (negatively charged) in solution get attracted to the positive charges on the fibre which eliminates the salt requirements for satisfactory dye exhaustion.

The investigation was conducted for cold brand, hot brand and highly exhaustive reactive dyes. The modified cotton showed excellent dye exhaustion for all the dyes in the absence of salt. The treatment was found to improve the dye fixation also. The modification was assessed through elemental analysis.

This study may be further extended to viscose material after suitably modifying the treatment conditions.

A pretreatment to cotton which could eliminate the usage of salt in its dyeing with reactive dyes is revealed.

The study explored a newer technique of cotton dyeing without salt usage. Both garment dyeing units and fabric/yarn finishing industries would thus be helpful.

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.

Dyeing of silk fabric was studied to increase dye uptake using eco-friendly glycerine based eutectic solvent (GES), which acts as a swelling agent.

The swelling behaviour of silk fabric in GES was analyzed using three-dimensional laser scanning microscope. Dyeing parameters such as time, temperature and GES concentration were optimized using design of experiments.

In total, 5.34 F-value and 0.0014 p-value of ANOVA represent that the model is significant. An optimized GES assisted dyeing was carried out with two different classes of dyes such as Acid Blue 281 and Acid Red 151 and further compared with that of conventional aqueous dyeing method.

At 70°C, silk fabric achieves desired colour strength after 35 min of dyeing (10 min lesser than conventional) using GES assisted dyeing method. % Dye exhaustion of GES assisted dye bath was carried out and found to be very good. Fastness properties such as washing, light and rubbing fastness of conventional and GES assisted dyed silk fabric showed comparable results.

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.

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.

Commercial natural dyes are quite costly as manufacturers are to follow multi-step extraction and purification procedures for standardisation purposes. Upon cost comparison, they lose in the market to synthetic dyes. However, in the handicraft sector, reproducibility may be of lesser importance against cost. In the present study, a domestic method of dyeing silk with the aqueous extract of raw plant/tree components (flower, leave, bark and root) by using a natural mordant and alum will be described. Good dyebath exhaustion and washing and light fastness are observed for some of the natural colouring matters.

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.

Pitting inhibition efficiency of SO₄⁻ and NO₃⁻ on AISI 316L stainless steel in contact with Cl⁻-containing fiber dyeing solutions together with the influence of the anions on absorption behavior of the solutions were investigated. The purpose of the study is to experimentally determine an optimized dyeing solution efficient on both – inhibition of the steel’s pitting and exhaustion of the dyes dissolved.

Methods such as electrochemical cyclic polarization, UV-visible range spectrophotometry and scanning electron microscopy have been used to assess the performance of two inhibitors on both pitting inhibition of the steel and dissolving ability over the reactive dyes. To find out a promising dyeing solution mixture in both aspects, Cl content of the original dyeing solution was replaced gradually with the inhibiting anions, where the total anionic content was kept constant to unchange the dye exhaustion potential of the solution. Then, those solutions came out with diverse pitting inhibition, and dye absorption levels were compared together for reducing/avoiding the pitting issues of the reactive dyeing vessels of the industry.

Rather high absorption levels detected by visible range spectrophotometry on the solutions showing sound inhibition levels indicated possibility of unaltered reactive dyeing qualities with an enhanced vessel lifetime as the inhibitive anions replace Cl⁻. Nitrate performed better than sulfate both on inhibition and absorption in the dyeing solutions. Also, 316L vessels became open to an extra anodic protection in inhibitor added solutions.

The findings are valid for a certain group of reactive dyes and dyeing solutions held at 70°C. However, the testing methods are available to almost any dyeing solution and dyeing temperature.

The work presents a combined testing of pitting inhibition and absorption behavior of dyeing solutions involving Cl⁻ that has not been reported so far. It shows that solution recipes least harmful to the steel vessels can be outlined for various reactive or other types of dye groups.

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.