A great deal of attention was addressed to the development of natural dyes that are safe, non-allergic, nontoxic, and environmentally friendly. In this investigation, Limoniastrum monopetalum leaves ...were studied as a source of ecological dye for cotton fabric dyeing. FT-IR spectroscopy indicated that the studied leaves were rich of hydroxyl and carbonyl groups suggesting the presence of phenolic and flavonoid structures. The extraction procedure was performed under different operating conditions; extraction time (5-90 min), temperature (30-120°C), pH (2-11) and aqueous extract concentration (10-90 g/L). Response Surface Methodology (RSM), with the assistance of Minitab17.1.0, was used to estimate the interaction between experimental factors. The optimum conditions for the extraction procedure were; time = 15 min, temperature = 40°C, pH = 9, and dye concentration = 80 g/L. Influences of the main dyeing conditions on the color strength (K/S) and the dye bath exhaustion E (%) were also discussed. The optimal values for dyeing were: pH of dyeing bath = 8.9, temperature = 100°C and dyeing duration = 43 min. The fastness properties of colored cotton samples were found to be improved using alum, chitosan, and pomegranate peel as mordants.
The present study was concerned with the extraction of natural colorant from kermes oak (Quercus coccifera L.) fruits and the application of the extracted dye on wool fibers in the presence and ...absence of various mordants. The effect of dyeing time and dye bath temperature were investigated. The effect of mordant type with different mordanting methods on dyeing quality was also examined. Four salt metals were used in this study; ferrous sulfate, stannous chloride, alum, and copper sulfate. The effect of these mordants on color of dyed wool samples was investigated in terms of CIELab (L*, a*, b*) and K/S values. Light, washing, and rubbing fastness of dyed samples were evaluated according to ISO standards. The obtained shades for the control samples were brown; while the mordanted samples a wide range of light to dark brownish colors with a significant enhancement in color strength values.
The results indicated that mordanting gave deep shades and enhanced fastness properties.
The subjects of this research are the burial clothes of Polish King Sigismund III Vasa and his wife Constance, which were woven and embroidered with silk and metal threads. Fragments of the textiles ...underwent spectroscopic, spectrometric, and thermogravimetric analyses. The hydrofluoric acid extraction method was improved to isolate various classes of dyes from the textile samples that had direct contact with human remains. High-performance liquid chromatography, coupled with diode array and tandem mass spectrometry detectors with electrospray ionization (HPLC-DAD-ESI-MS/MS) facilitated the detection and identification of colorants present in the textiles. Cochineal, indigo-, madder-, orchil-, and tannin-producing plants were identified as the sources of dyes used. Scanning electron microscopy with an energy-dispersive X-ray detector (SEM-EDS) was employed to identify and characterize the silk fibers and mordants and the metal threads. The presence of iron, aluminum, sodium, and calcium in the silk threads suggests their potential use as mordants. The analysis of the metal threads revealed that most of them were made from flattened gilded silver wire, with only a few being cut from a sheet of metal. Typical degradation mechanisms of metal threads were shown, resulting from both burial environment and earlier manufacturing process, and the use of the textiles in clothing, i.e., a significant loss of the gold layer was observed in most of silver gilt threads, caused by abrasion and delamination. The results of the thermal analysis confirmed the presence of silk and silver threads in the examined textiles.
Due to an increasing awareness of the harmful effects of synthetic dyes among the global community, the demand for natural dyes in the textile sector has increased. The current study has been ...conducted to explore coconut coir, that is, Cocos nucifera, as a new dye yielding plant for wool dyeing under ultrasonic (US) radiation. Unirradiated and US-irradiated extracts of coconut coir were utilized to dye unirradiated and US-irradiated wool fabrics. To make the process more sustainable, acacia, henna, turmeric and pomegranate extracts as biomordants were used to dye wool fabric at 65℃ for 45 min. It was found that a good color yield was achieved by dyeing US-treated wool with US-treated acidic methanolic extract at 65℃ for 45 min. It is found that biomordanting profoundly added value in coloration and also enhanced the fastness rating of the dyed wool fabrics. It is concluded that US rays have excellent efficacy for exploring the coloring wealth of plants for dyeing of natural fabrics.
Coloured textile products are more marketable, and are therefore always in higher demand. This has increased the use of synthetic dyes in the textile industry, thus raising environmental pollution ...associated with synthetic dyes. Natural dyes have been shown to be suitable alternatives. However, the use of metallic mordants during dyeing means the process is not eco-friendly, hence the need to develop bio-mordants that can be used as alternatives to some toxic metallic mordants. In this study, the effects of bio-mordants on the dyeing properties of Euclea divinorum Hiern (Ebenaceae) dye extract were assessed using different mordanting methods on cotton fabric. Dyeing characteristics were evaluated in terms of colour fastness and colour strength. Antioxidant textile finishing properties of the natural dye on cotton fabric was determined using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) method. The bio-mordants improved the colour strength for dyed cotton fabric from 0.612 to 0.863 and 0.911 for the cotton fabric mordanted with mango and rosemary, respectively. This study identified an important basis of suitable bio-mordants that can be applicable when dyeing cotton fabric with E. divinorum natural dye. In addition, the good antioxidant activity of 72.5% indicates that E. divinorum dye extract is a promising agent for the future development of bioactive, protective and health textile fabric.
The worldwide demand has been raised to use natural dyes in all applied fields of life due to their environmental-friendly and therapeutic nature. For the current study microwave rays as an ...eco-friendly extraction tool has been used to explore the natural coloring potency of Arjun bark for cotton dyeing. Arjun bark powder was exposed to microwave irradiation for up-to 5 min and was used for extraction of colorant in different media. It has been found that 50 mL of acidified methanol-solubilized extract obtained from 5 min microwave-treated powder has given excellent results when employed onto MW treated cotton at 55°C for 75 min, salt of Fe as chemical mordant and extracts of acacia and turmeric as bio-mordants employed at optimum condition has shown good to the excellent fastness ratings at grey scales. It is concluded that microwave treatment has good potential for the extraction of the colorant from Arjun bark for cotton dyeing and the application of sustainable mordants has made the process more aesthetic and sustainable.
In recent years there has been a great interest in the application of natural dyes in dyeing textiles due to their biodegradability and high compatibility with the environment. According to the ...experts, there is a great potential for using natural dyes to the extent that in some areas they can very easily replace synthetic ones. This paper reports the studies available on the characterization, classification and analysis of natural dyes; extraction of dyes from onion's outer shell and effects of different mordants and mordanting methods on the color shade. From an environmental point of view, replacing synthetic dyes with natural ones is not only a strategy to reduce risk and pollutants, but also an opportunity for new markets and jobs.
In the present work, cotton fabrics were dyed with natural dye extracted from the barks of a plant named Calligonum comosum. The dyed fabrics were mordanting with four mordants (potassium aluminium ...sulphate, black eco-crumb, ferrous chloride, and ferrous sulphate) applied separately. The effect of the mordants was described by XRD, FT-IR, SEM, DSC and TGA techniques. From the obtained results, various bands ratio displayed differences was observed; FT-IR shows a decrease in O-H band intensity; SEM images illustrate that the fabric was firmly woven. Thermal results propose the improvement of the thermal molecular mobility of the cellulose molecules. The evaluation of antimicrobial activity was tested using the modified streak method. The data indicated that the dyed and treated cotton fabrics with ferrous chloride and ferrous sulphate mordants have higher crystallinity indices in agreement with the obtained thermal data and exhibited higher thermal stability as well as expressively altered the morphological structure of cotton fabrics, and imparted a series of functionalities including; antioxidant and antibacterial properties to cotton fabrics.
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In the present study Terminalia chebula was used as an eco-friendly natural colorant for sustainable textile coloration of woolen yarn with primary emphasis on thermodynamic and ...kinetic adsorption aspects of dyeing processes. Polyphenols and ellagitannins are the main coloring components of the dye extract. Assessment of the effect of pH on dye adsorption showed an increase in adsorption capacity with decreasing pH. Effect of temperature on dye adsorption showed 80°C as optimum temperature for wool dyeing with T. chebula dye extract. Two kinetic equations, namely pseudo first-order and pseudo second-order equations, were employed to investigate the adsorption rates. Pseudo second-order model provided the best fit (R2=0.9908) to the experimental data. The equilibrium adsorption data were fitted by Freundlich and Langmuir isotherm models. The adsorption behavior accorded well (R2=0.9937) with Langmuir isotherm model. Variety of eco-friendly and sustainable shades were developed in combination with small amount of metallic mordants and assessed in terms of colorimetric (CIEL∗a∗b∗ and K/S) properties measured using spectrophotometer under D65 illuminant (10° standard observer). The fastness properties of dyed woolen yarn against light, washing, dry and wet rubbing were also evaluated.
Global heat, carcinogenic, and viral diseases created due to industrial pollutants has led people to shift toward natural products particularly natural dyes in all walks of life. In this study, U.S. ...rays up-to 60 min, were used to extract the color in aqueous medium and employed onto silk fabric at selected conditions. It has been observed that good color strength has been found when 30 mL of acidic extract (pH = 4.0) obtained from 6.0 g of Harmal powder containing 3.0 g/100 mL of salt as an exhausting agent was employed onto the US treated silk at 65ºC for 55 min. The utilization of the extract obtained from 7% of pomegranate as post-bio-mordant, 3% of acacia extract as meta-bio-mordant, and 7% of henna extract as meta-bio-mordants has given excellent color strength. In comparison, 5% of Al salt as meta mordant, 5% of Fe salt as pre mordant, and 7% of tannic acid as meta-mordant has given better results. ISO standard methods for fastness employed onto optimum mordanted dyed fabrics have given well to excellent fastness ratings. Hence, natural colorant extracted from Harmal seeds has excellent coloring efficacy to dye silk fabric under sustainable conditions, whereas the addition of eco-friendly mordants for shade development process has made the coloration of silk more sustainable with improved colorfastness properties.
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