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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.

Chitosan is widely considered as a natural polymer and a diverse finish to impart antibacterial property and enhanced dye uptake of textiles. Herein, the authors have investigated the feasibility of using chitosan/starch blend as a thickener in screen printing of cellulosic fabrics with some natural dyes.

The polymeric blend of chitosan/starch was prepared and used as a thickener for screen printing with three natural dye extracts, namely, Curcuma tinctoria (turmeric), Beta vulgaris (beet) roots and Lawsonia alba (henna) leaves on cellulosic fabrics like cotton and viscose. The viscosity and rheological properties of print paste as a fresh and after overnight shelving were examined. The influence of polymeric blends on cellulosic fabrics' print properties was inspected by determining their colorfastness, rubbing fastness, tensile strength and antibacterial activity.

The results depicted that chitosan/starch blend as printing thickener increased the shade depth with good wet and dry rubbing fastness for all the test natural dyes. The antibacterial activity of resultant printed cellulosic fabrics was found to be satisfactory against broad-spectrum bacterial strains.

This study's outcome is the development of chitosan blend thickeners to print the cellulosic fabrics with indigenous natural dyes.

The authors found no previous report on the synthesis of chitosan-based antibacterial blend thickeners with three distinct natural dyes and their application in screen printing of native and regenerated cellulosic fabrics of cotton and viscose, respectively.

This paper is a review article which presents brief historical information about natural dyes in different historical periods in Egypt. This information will assist archaeologists, dyers, artists and conservators who seek information about ancient dyes in Egypt. For example, the data will help conservators in choosing natural dyes that can be used in producing new models of dyed textile samples that simulate the original historical ones. These models of textile samples can be used as experimental samples in conservation research and training of young conservators. Also, this information can be used by technologists to conduct comparison studies on the technology of natural dyes in ancient Egypt. The dyes are presented according to their alphabetical names in this paper. All data in this paper have been collected from references related to this topic without any changes from the researcher.

Natural colorants are believed to be safe because of their nontoxic, noncarcinogenic and biodegradable nature, and also, the demand for natural dyes is steadily increasing. This study aims to investigate the dyeing of polyethylene terephthalate (PET) fabrics under cold plasma and ultraviolet (UV) radiation conditions with Prangos ferulacea.

In the first, some PET fabrics were modified using UV radiation and some others by cold plasma (oxygen/argon), and then the dyeing of fabrics with the natural dye was done (100°C/130°C) without using metallic mordant. Dyeability (color strengths) of the treated samples, colorfastness to washing, light and rubbing, water absorption time, crease recovery angle, air permeability and mechanical behavior were investigated.

The maximum color strength (k/s = 4.87) was achieved for the fabric exposed to UV radiation for 2 h and then dyed with Prangos ferulacea at 130 °C. The results indicated that the dyed fabric showed acceptable colorfastness (very good–excellent) properties in washing and rubbing fastness except for colorfastness to light (moderate). The strength and the angle of crease recovery of treated and dyed samples have increased, while the time of water absorption and air permeability have decreased.

The surface modification of PET (UV radiation and plasma treatment) provides a new idea to improve the dyeability of PET with Prangos ferulacea natural dye without using metallic mordant.

Considered as one of the most unwanted species by the International Union for Conservation of Nature, the Prosopis juliflora plant is a noxious and invasive weed. Recent studies suggest that the heartwood of the plant has an unusually high amounts of flavonoids with potential medicinal properties and dyeing potentials. In this work, acetonic extracts were successfully valorized into a natural dye.

After extraction and optimization of dyeing conditions, the fabric was treated by using pre-mordanting, simultaneously mordanting and post mordanting techniques. The dyed samples were then evaluated by using standard methods ISO 105-C06, ISO 105-A02, ISO 105-X12 for wash, light and rub fastness, respectively.

Dye fastness ranged from good to very good with mordants improving both wash and rub fastness. Optimum pH for dyeing was found to be at 7.2 at temperatures of 60°C and a dyeing time of 80 min. Application of mordant in dyeing white fabric showed improved dyeing properties in post mordanting than both pre-mordanting and simultaneous mordanting.

To best of the authors’ knowledge, this paper details for the first time how a noxious weed can be transformed into a natural dye, with potential applications to the textile industry.

The dyeing of cellulosic and proteinous fibers with natural and synthetic colorants usually needs large amounts of metal salts to promote the dyeing procedure. To get rid of the necessity to use metal salts, plasma treatment and subsequent attachment of chitosan biopolymer were considered as green processes for surface functionalization of wool and cotton. The purpose of this paper is to investigate the effect of oxygen plasma treatment and attachment of chitosan on the dyeability of wool and cotton fabrics using walnut and weld as model natural dyes, as well as C.I. reactive blue 50 and C.I. acid blue 92 as model synthetic dyes.

Wool and cotton fabrics were modified with oxygen plasma and coated with chitosan solution. The un-modified and modified samples were dyed with the above-mentioned dyes under constant conditions. The color strength, color coordinates and fastness properties of the dyed samples were determined and compared.

The results showed that oxygen plasma treatment could improve the dyeability and fastness properties of wool and cotton fibers when dyed with all of the above-mentioned dyes. Attachment of chitosan to the plasma-treated samples significantly improved the dyeability of wool and cotton fibers with walnut, acid and reactive dyes. The fastness properties of the dyed samples were enhanced by plasma treatment and chitosan coating.

This study uses plasma treatment as an environmentally friendly pre-treatment for attachment of chitosan on wool and cotton. This process improved the dyeing properties of both fibers. The use of metal salts in not needed for dyeing of wool and cotton according to the investigated process.

In nature, thousands of different colours and shades exist. Basic set of dyes, namely, yellow, red, blue and green are necessary for a complete colour gamut. Creating a complete gamut with natural dyes with one common extraction and application procedure is not exploited hitherto. The paper aims to discuss this issue.

In this study, an attempt was made to create a complete colour gamut with easily available natural dyes with one common extraction and application procedure.

Silk fabrics were dyed using various natural dyes alone and in combination to yield various shades, namely, yellow, red, green, blue. Pre-mordanting of silk fabrics was carried out with mordants, namely, alum, ferrous sulphate, copper sulphate, stannous chloride, potassium dichromate followed by dyeing. The fastness properties and colour strength values of all the shades obtained were determined.

Creating a complete gamut with natural dyes with one common extraction and application procedure is not exploited hitherto.

The paper aims to investigate the feasibility of developing natural dyes from the barks of Araucaria columnaris and leaves of Macaranga peltata, Averrhoa bilimbi. The paper also deals with the application of natural dyes in textile coloration.

Dye extraction was carried out using the aqueous method. The dyeability of the aqueous extract was assessed on cotton, silk and polyester yarns using different mordants (alum, acetic acid, CuSO₄, lemon juice) and without mordant. UV–Visible spectral analysis and pH of different natural dyes were determined. Percent absorption, K/S values, CIELab values and fastness properties of the selected dyed yarns were also assessed.

The percentage values for dye exhaustion differed with various mordants. The K/S values were found to be influenced by the addition of mordants. Different hues were obtained with the usage of different mordants. Fastness results exhibited good to very good grades.

The effective application of aqueous method of dye extraction in the study avoids solvent toxicity. The current results proved that the dyeing could be achieved at room temperature for different yarns (cotton, silk, polyester). At present, no report exists in the literature of research work on the extraction of natural dyes from the leaves of M. peltata, A. bilimbi and their dyeing potential on cotton, silk and polyester.

The present work offers new environment-friendly dye as well as simple dyeing method. Barks and leaves are promising sources of dye. Enormous availability of barks and leaves avoids the exploitation of the plant parts for the extraction of natural dyes.

The important feature of this study was the effective dyeing of natural and synthetic fibers at room temperature. The novel sources of natural dyes would contribute significantly to the existing knowledge of dyeing, and the natural dyes reduce the environmental impact of synthetic dyes.

This paper aims to investigate the feasibility of developing an eco-friendly dyeing process for a regenerated polyester fiber (polytrimethylene terephthalate) using a natural dye (Lac) and bio-mordant.

The effects of temperature, time, initial pH of dye bath, material to liquor ratio and mordant concentration on color strength of polytrimethylene terephthalate fiber dyed with Lac were examined. The results were compared using three bio-mordant (catechu, myrobalan and pomegranate) and three inorganic mordant (alum, ferrous sulfate and stannous chloride). Single replicate of 25-design methodology was used to identify three significant factors affecting color strength, and optimization was done using response surface methodology based on 2³-central composite rotatable design.

Color strength achieved using catechu as a bio-mordant was close to that with ferrous sulfate and higher than with stannous chloride. Temperature, initial pH and mordant concentration were identified as significant factors affecting color strength of dyed fiber with catechu. Optimization revealed temperature of 133OC, initial pH of 6 and bio-mordant (Catechu) concentration of 10 per cent to be the optimal conditions for dyeing, with K/S value of 4.55.

The study revealed the possibility of satisfactory dyeing of regenerated polyester fibers with natural dyes, replacing disperse dyes. The comparison of color strength achieved indicated the possibility of replacing inorganic mordant with bio-mordant in such dyeing process. The dyeing process could thus be made more eco-friendly by removal of toxic chemicals from effluents.

EVEN though, as all technical journals should be, we are completely apolitical, we cannot but notice that a General Election will be over by the time these words reach our readers. Who will win is, at this stage, anybody's guess—and many persons' hopes and fears.