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The study aims to test the color fastness of wool and linen fabrics dyed by simple immersion in ethanol dissolutions of fungal dyes.

Ethanol dissolutions of Talaromyces australis and Penicillium murcianum dyes were prepared to a concentration of 0.3% and used to dye wool and linen samples by immersion. Color fastness to washing, dry cleaning, wet and dry rubbing, perspiration and light, were tested according to AATCC standards.

Color fastness reached acceptable results at dry cleaning and wet and dry rubbing by crocking but did not performed well at laundering, perspiration and light exposure. Results indicate that ethanol dissolutions of tested dyes had better affinity for wool fabrics than linen, but the dyeing method requires further improvements to be considered attractive for full scale applications.

In this work sustainability of fabrics dyeing is improved by using natural pigments produced by filamentous fungi and a method to dye that requires no increment of temperature and mordants.

In recent years, natural dyes have attracted significant attention globally because of growing public awareness of the environment and health hazards associated with synthetic dyes. Natural dyes can provide special aesthetic qualities as well as the ethical significance of a product which is environmentally friendly. By keeping this burning issue in mind, this study aims to explore the dyeing properties of various unexplored environmentally friendly natural dyes.

In this study, the aqueous extract of coconut leaves is used for dyeing purpose. The silk and jute fabrics were dyed with the extract alone as well as in combination with metal salts as mordants by employing pre-, meta- and postmordanting techniques. The dyeing properties of the colored samples were evaluated by measuring their color strength; CIEL*a*b* values; and color fastness to washing, light and rubbing.

A yellow shade was achieved when the fabric samples were dyed solely with the extract. However, shade variations were observed when different mordants and mordanting techniques were applied. In all the cases, metallic salts improved the color fastness properties of dyed samples to washing, light and rubbing especially for the silk fabric.

To the best of the authors’ knowledge, this is the first report on a natural dye extracted from the leaves of coconut. Leaf as the source of dye has added an extra advantage, as it is reproducible and can be collected easily without harming the plants. The reported dye could be an attractive choice for sustainable and eco-friendly dyeing.

The textile industry has consumed large quantities of water and discharged large volumes of wastewater in the dyeing process. The study aims to characterize self-dyed silk with Rhodamine B (RhB) for fashion applications to reduce textile hazards to the environment and increase the added value of silk.

Bombyx mori was fed with RhB-colored mulberry leaves (1500 ppm). The effects of self-dyeing were investigated via color strength K/S, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscope, X-ray diffraction, tensile strength, color fastness to washing, rubbing, perspiration and light.

Self-dyed silk possesses effective coloration and impressive color fastness (4–5/5), higher crystalline index (CrI) (73.26 ± 2.28%), less thermal stability and tenacity, slight change in amino acid composition compared with the pristine and no existence of harmful aromatic azo amines and arylamine salts.

The application of self-dyed silk with RhB dye has expanded new technology into fashion industry, contributing partly to economic growth and adding value to silk in the global supply chain. Besides, the self-dyeing will yield practical values in the reduction of dyeing discharge in textile industry.

Self-dyed silk was characterized for textile applications in comparison with pristine silk in terms of color strength and fastness as well as determined its polymeric properties relating to crystallinity, morphology, chemical composition, tensile properties and thermal stability which have not been investigated before.

The purpose of this study is to extract and characterize a novel natural dye from the leaves of Lannea coromandelica and the extraction with finding ways of dyeing cotton fabric using three mordants.

The colouring agents were extracted from the leaves of Lannea coromandelica using an aqueous extraction method. The extract was characterized using analysis methods of pH, gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared (FTIR), ultraviolet-visible (UV-vis) and cyclic voltammetry measurement. The extract was applied to cotton fabric samples using a non-mordant and three mordants under the two mordanting methods. The dyeing performance of the extracted colouring agent was evaluated using colour fastness properties, colour strength (K/S) and colour space (CIE Lab).

The aqueous dye extract showed reddish-brown colour, and its pH was 5.94. The GC-MS analysis revealed that the dye extract from the leaves of Lannea coromandelica contained active chemical compounds. The UV-vis and FTIR analyses found that groups influenced the reddish-brown colour of the dye extraction. The cyclic voltammetry measurements discovered the electrochemical properties of the dye extraction. The mordanted fabric samples showed better colour fastness properties than the non-mordanted fabric sample. The K/S and CIE Lab results indicate that the cotton fabric samples dyed with mordants showed more significant dye affinities than non-mordanted fabric samples.

Researchers have never discovered that the Lannea coromandelica leaf extract is a natural dye for cotton fabric dyeing. The findings of this study showed that natural dyes extracted from Lannea coromandelica leaf could be an efficient colouring agent for use in cotton fabric.

The purpose of this paper is to synthesise some disperse dyes containing a reactive group and study their applications on polyamide and wool printing by heat transfer and screen printing.

To prepare these dyes, arylhydrazones of acetylacetone were reacted with cyanothioacetamide in boiling ethanolic sodium ethoxide. The resultant salt was collected by filtration and dried, then the salt was dissolved in ethanol and reacted with chloroacetylchloride with stirring for 3 h, where chloroacetylechloride was added dropwise. The final precipitated product was collected by filtration and crystallised with an appropriate solvent. These prepared dyes were used to print polyamide and wool fabrics by using synthetic thickener in the printing paste for all techniques.

The structure of the synthesised dyes were established and confirmed for the reaction products on the basis of their elemental analysis and spectral data (MS, IR and ¹H‐NMR). The suitability of the prepared dyestuffs for either heat transfer printing or traditional printing on nylon 6 and wool fabrics was investigated. The prints obtained from dyes possess high‐colour strength as well as excellent overall fastness properties.

The synthesised heterocyclic reactive disperse azo dyes were prepared from the reaction of arylhydrazones of acetylacetone and thiocyanoacetamide to form the corresponding pyridinethione salts which underwent further reaction with chloroacetylchloride. The obtained dyes were utilised in preparing a paste for polyamide and wool fabric printing. In addition, both of the variation of the substituents on the synthesised dyes and the fastness properties were also studied.

The synthesis and use of reactive disperse dyes provide practical solution to over come the low fastness on polyamide and wool, when they are printed with disperse dyes only.

The result of the work aimed to define the scope and limitation of the authors' procedures for the synthesis of novel reactive disperse azo dyes to improve the low‐fastness properties of polyamide and wool, the dyes were synthesised in a simple way.

The purpose of this study is to investigate the physical, ultraviolet (UV), colour appearance and colour fastness properties of selected fabrics dyed with natural dyes from Daboya and Ntonso communities of Ghana. The study further highlights the rich cultural heritage of traditional dyeing from these two communities. Craftsmen in West Africa especially Ghana, have sustained the traditional dyeing methods to produce textile products for consumers.

In this study, two sample fabrics were purchased from craftsmen at Ntonso and Daboya communities in Ghana. These fabrics were analysed at the laboratory under standard test methods for their physical, UV, colour appearance and colour fastness properties.

Results showed that all the sample fabrics have good UV shielding performance (ratings above 50+). Daboya sample fabrics (dyed with indigo dyes) produced more colour stains than the sample fabrics from Ntonso (dyed with black “kuntunkuni” dyes). The K/S_sum value or colour yield reduced after washing but that alternatively increased the calculated ultraviolet protection factor.

Findings from this study exposed the unique UV performance of dyed traditional fabrics (using natural dyes) from Ntonso and Daboya communities in Ghana. This inspires and enforces the need for craftsmen to improve their production cycle to produce these fabrics in different sizes which provides the necessary UV shielding abilities for consumers in the wake of climate changes.

This study demonstrated that the natural dyeing process at the two communities produced relatively good UV and colour fastness properties of the sample fabrics. These eco-friendly dyeing practices have survived over time to maintain and promote the concept of sustainability within the textile and fashion industry in Ghana.

Equisetum arvense L. (Equisetum) is a weed that is very difficult to remove because of its deep roots. The purpose of this paper is to examine the dyeability and antioxidant activity of Equisetum extracted from hot water.

Dry Equisetum was extracted at 100°C for 2 h, and its dyeability according to time, temperature and repetition cycle, and the mordant effect by skim milk powder were confirmed. The color change according to the K/S, fastness to rubbing, light, sweat and washing, UV protection rate and antioxidant activity were evaluated.

UV‒Vis spectroscopy showed that the Equisetum extract contained a flavonoid compound. The addition of Equisetum to artificial silk produced the greatest color difference when dyed at 60°C for 1 h, and the K/S value increased slightly after the pre-mordant treatment. In the fastness test, light and washing had no significant effect, but the fastness to rubbing was very good at Grades 4 and 5, and there was also a considerable improvement in the UV protection rate. The antioxidant activity of the extract was confirmed by an analysis of the radical scavenging ability through the DPPH (1,1-diphenyl 2-picryl-hydrazyl) and ABTS ([2,2’- azino-bis (3-ethylbenzothialzoline-6-sulfonic acid) diammonium salt]) tests.

These results revealed a new natural antioxidant-containing dyestuff, weed grass, which is easy to obtain, easy to use as a dyeing material and has excellent antioxidant activity in an extracted dye solution and dyeing fabric.

The purpose of this paper is to evaluate the efficiency of ultrasonication on new natural dye obtained from leaves and stem extracts of Daphne papyraceae using metal mordant for good cotton, silk and wool dyeing prospects. It also proposes to effect the characterisation of the colorant.

For effective natural dyeing with leaves and stem extracts of D. papyraceae, both conventional and sonication methods for cotton, silk and wool dyeing were carried out using metal mordants. The purpose of using sonication was for betterment of dye uptake, improved dye adherence and good wash and light fastnesses. Results show marked improvement by the chosen dyeing method. Simultaneously, chemical characterisation of the colorant was carried out by first column chromatographic separation of the crude extract, followed by spectral analysis of the isolated products.

The superiority of sonicator dyeing over conventional dyeing in terms of enhanced resource productivity and, as a result, reduced wastes makes it the established best available technique in the natural dyeing industry. This fact has been examined for several natural dyes. Use of sonicator shows marked enhancement for cotton‐, silk‐ and wool‐dyed fabrics. Typical bath liquor to fabric ratio for conventional dyeing varies from 20:1 to 15:1 and for sonicator dyeing from only 12:1 to 10:1, thereby reducing specific water and energy consumption by 30 and 50 per cent, respectively. The cycle time for dyeing was also reduced by 50 per cent and this would benefit the dyeing process with more tonnage of fabric per unit time and with lower waste generation. This would also result in improved capacity utilization leading to enhanced productivity levels in the dyeing houses.

Although metal mordanting with copper sulphate and potassium dichromate is not ecofriendly, only 2 per cent of these metal salts has been used to prepare different shades with leaves and stem extracts of D. papyraceae for cotton, silk and wool fabrics.

The method developed for natural dyeing of cotton, silk and wool fabrics using sonication in conjunction with metal mordanting has shown marked improvement. The chemical composition of the crude extract shows the presence of flavonoids and other specific natural pigments.

The method developed for natural dyeing of cotton, silk and wool fabrics using stem and leaves extracts of D. papyraceae under sonication in conjunction with metal mordanting has shown marked improvement in terms of dye adherence and fastness properties and can thus be recommended for industrial application. This is a new source of natural dye.

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.