Coloration Technology最新文献

Molecularly imprinted materials based on imprinting dithizone-Zn (II) (DTZ-Zn (II)) complexes onto cotton fabric/silica, and the Color Grab application for the OPPO A54 smartphone, were proposed and applied for the first time to detect Zn (II) ions in water samples. The proposed materials were prepared by using cotton fabrics as cellulosic materials, tetraethoxysilane as silica sources and DTZ-Zn (II) as template molecules. The initial concentration of DTZ and Zn (II), the volume of tetraethoxysilane and the reaction time were optimised to obtain the maximum adsorption of the DTZ-Zn (II) complexes in the imprinted materials. The concentration of hydrochloric acid and the extraction time were optimised to obtain the maximum Zn (II) removal. The results found that 10 mL of a solution containing DTZ (0.20 mM) and Zn (II) (0.30 mM), 25 μL of tetraethoxysilane, with 10 minutes reaction time, exhibited the strongest binding of the template complexes. Zn (II) ions were selectively removed from the materials by using 0.1 M hydrochloric acid for 10 minutes. The morphology of the prepared materials was characterised by scanning electron microscopy–energy-dispersive X-ray spectroscopy and attenuated total reflectance–Fourier Transform-infrared spectroscopy. The smartphone measurement based the cotton fabric/silica materials exhibited linear relationship between saturation (%) and Zn (II) concentrations in the range of 0.1 to 1.0 mg/L, with limit of detection of 0.02 mg/L and limit of quantification of 0.06 mg/L. The proposed method was successfully applied to determine Zn (II) in real-water samples with the % recovery ranging from 98% to 115% and an acceptable relative standard deviation of less than 6 (n = 3).

In this study, an attempt has been made to dye cotton/acrylic blend fabrics in a single-bath-single-stage method considering today's growing market for such blended products. Yarn-blend cotton/acrylic fabric was produced and dyed at 3% shade using indigo dye in the exhaust method to optimise the dyeing conditions by varying the amount of reducing agent, pH, and dyebath temperature. The colour yield of both the acrylic part and cotton components of the blend was influenced by pH levels. Meanwhile, the temperature played a notable role in determining the colour yield of the acrylic portion. Optimised dyeing conditions were obtained at pH 6 and 120°C for the acrylic part, whereas pH 11 and 90°C temperature were obtained for the cotton part. These conditions involved the use of sodium dithionite (15 g/L) as a reducing agent and sodium hydroxide as an alkali. While the yarn-blend fabrics exhibited a unique shadow dyeing effect, solid dyeing results were achieved with fibre-blend fabrics, underscoring the versatility of this single-bath-single-stage method. To assess the overall dyeing performance, comprehensive evaluations including bursting strength measurements, assessments of fastness to washing, perspiration, and rubbing were conducted, all of which provided valuable insights into the durability and colour retention of the yarn-blend fabrics. This research not only addresses the demand for cotton/acrylic blend fabrics in today's market but also demonstrates an efficient and innovative single-bath-single-stage dyeing approach using indigo dye, which holds promise for the textile industry's future sustainability and product diversity.

The tones of iron oxide pigments range from yellow, red, brown and green to black. Iron oxide pigments are non-toxic and have a nanometric particle size, which makes them ideal for use as pigments. The current study synthesised synthetic inorganic pigments based on iron oxides using the alkaline precipitation method. This approach to the synthesis of iron oxide pigments makes them less expensive for obtaining reproducible colours. Iron salts (iron (III) chloride, iron (III) nitrate, iron (II) sulphate [ferrous sulphate] and iron (III) sulphate) have been combined with alkaline solutions (sodium hydroxide, potassium hydroxide and ammonium hydroxide) to form coloured iron oxides, which are widely known as natural inorganic pigments. The 12 samples produced in four different colours (red, yellow, brown and black) were left in aqueous suspension and dispersed in commercial real white estate paint, to evaluate their behaviour as pigments. Structural characterisation (X-ray diffractometry), composition (X-ray fluorescence by dispersive energy), thermal analysis (i.e. thermogravimetric analysis and the differential thermal analysis) and spectroscopy (FTIR and photoacoustic), as well as colorimetry, were performed. The phases indexed by X-ray diffractometry were goethite, haematite, magnetite and lepidocrocite. The inorganic pigments produced are compatible with natural inorganic pigments. They also showed dispersion compatibility in commercial white paint without changing the surface coating powder and are therefore an alternative to synthetic inorganic pigments.

The difficulty of dyeing is a disturbing problem for the various application of polyimide fabrics. Alkali treatment has been widely used as a preliminary step before dyeing, denoted as a two-bath method. With more attention being paid to energy resources, this work aims to explore more economical and environmentally friendly dyeing technology, combining the alkali treatment and the dyeing process together, named a one-bath method. Surprisingly, the K/S value of the one-bath dyed fabric is much higher than that of the two-bath sample, in which the red colour value is enhanced by 59.9% for the one-bath sample. As for the effect of dyeing on the physical properties, the two-step method has been demonstrated to exert more severe damage on the fibre, with lower crystallinity and tensile strength. To explain such results, it is deduced that when alkali is added together with dyes, it can play a bridge role between the dyes and the fibre, anchoring the dyes wherever the alkali can permeate. Furthermore, 17.25 J of the energy is calculated to be saved for the dyeing of 60 g of fabric, which is very inspiring for large-scale application.

The high demand for novel antimicrobial textiles by the medical, healthcare, hygiene, sportswear, personal protective equipment and filtration sectors has promoted the growth of functional textiles. However, the efficacy of antimicrobial agents against different pathogens is a considerable challenge because of the distinctive mechanisms of action and resistance. The development of novel synergistic antimicrobial dyes may offer numerous opportunities to enhance antimicrobial effectiveness. In this work, a novel imidazole-based azo dye with a p-methoxyphenyl group in the N-1 substituent of the imidazole ring (AzoIz-a), and corresponding amidrazone precursor (AmIz-a), were combined with polyvinylpyrrolidone-coated silver nanoparticles (AgNPs). The molecules, alone and combined with the AgNPs, were characterised by ultraviolet-visible spectrophotometry and zeta potential. Their synergistic effect was assessed against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The results were compared with a previously reported imidazole-based azo dye and precursor containing a methyl group in the imidazole ring (AmIz-b and AzoIz-b). The results showed interesting antimicrobial properties of the novel AzoIz-a molecules when combined with a very small concentration of AgNPs. The combination showed an additive effect for S. aureus and a synergistic effect for E. coli and P. aeruginosa. Considering the synergistic results, the effective concentration of the AzoIz-a decreased from more than 128 to 16-32 μg.mL⁻¹ by the addition of a small concentration of AgNPs (0.6-1.3 μg.mL⁻¹), which displayed comparable results with the AzoIz-b molecule. Thus, the application of these conjugates in textiles may lead to highly coloured materials with remarkable anti-bacterial properties, which warrant further exploration.

Traditional textile dyeing processes usually require large quantities of water and energy and generate wastewater that can be harmful to the environment. Dyeing in supercritical carbon dioxide (sc-CO₂) media is promising in textile coloration due especially to it providing a waterless process and eliminating the need for an energy intensive drying step. The natural anthraquinone emodin showed promising results for dyeing different fibres through sc-CO₂ process. However, emodin is mutagenic. The aim of this study was to develop non-mutagenic derivatives of emodin that can be applied to textiles using sc-CO₂. Emodin structure was modified incorporating acryloyl groups, which are considered suitable for decreasing potential for DNA intercalation, and thus mutagenicity. The presence of acryloyl groups would also enable atmospheric plasma induced bonding with fibres. Molecular modelling studies showed that emodin derivatives became less planar with increasing number of attached acryloyl groups, making intercalation unlikely. The derivatives produced were tested to assess mutagenicity in vitro (Salmonella/microsome assay, TA1537, 10% S9) and in vivo (micronucleus test in hemocytes of aquatic crustacean). We found that emodin can be derivatised using acryloyl chlorides to give mono- and di-acrylate esters suitable for dyeing polyester fibres in sc-CO₂. However, the new dyes presented mutagenicity for both in vitro and in vivo. Although the derivatives provided greenish-yellow alternatives to emodin for dyeing synthetic fibres, they do not appear to be viable alternatives from the point of view of preserving human and environmental health. Plasma bonding studies are underway.

In this research article, it is reported the preparation and characterisation of four types of blended cotton-polyester based textile materials in different dye ratios with four kinds of natural dyes of agro waste (walnut shell, onion peel) and wildflowers (tansy, Hypericum) with/without mordants as antibacterial and antifungal species for shoe materials. The dyed samples were spectrophotometrically measured and the results were obtained as colour strength (K/S) as well as CIELab values. As a result, dyed fabrics with natural dyes showed yellow, grey, orange and brown colours. With the help of a mordant, aluminium-potassium, the dyed fabrics obtained natural, not distorted shades of these colours, and with the addition of copper sulphate, they showed changing yellow to light green, orange to dark red, grey to a darker shade of grey and brown to a darker colour. The dyed samples were tested for colour fastness to circle rubbing and satisfactory results were found. The fabrics dyed only with natural dyes and treated with natural dye and mordants were evaluated for antibacterial and antifungal properties against Escherichia coli, Staphylococcus aureus, and Candida albicans. The results indicated that fabrics treated with these natural dyes and mordants had excellent antibacterial and antifungal activity. All natural dyes and mordants used in this study were the most effective and showed the maximum inhibition zone, indicating the best antimicrobial and antifungal activity against tested microbes. The results showed that all these natural dyes can provide some antibacterial and antifungal activity on mixed fabrics.

Electrochromic materials (ECMs) have important potential applications in the field of intelligent optoelectronic displays. However, ECMs and its devices cannot be truly applied on a large scale until the problem of their long-period performance degradation is really solved. This article focuses on summarising the attenuation mechanism of common ECMs, which is mainly divided into three types: structural damage, irreversible reaction and ion capture, and summarises four optimisation strategies for the cyclic stability of ECMs at the present stage: doping is used to change the internal structure of the material in order to achieve the purpose of improving the cyclic stability; composite means to allow a variety of materials to interact with each other in order that the original material has no excellent performance; improve the cyclic stability of ECMs by the special characteristics of nanostructures; and enhance the performance by optimising the preparation process and regulating the parameters in the preparation process. Finally, the article discusses the potential for optimising the long-term stability of ECMs in the future, based on the earlier-mentioned research.

Hypochlorite is a kind of endogenously produced reactive oxygen species (ROS) in the human immune system and plays a crucial role in many pathophysiological processes. In this work a novel fluorescent probe derived from 6-methylthio coumarin was designed and synthesised for detection of hypochlorite in acetonitrile/phosphate-buffered saline (MeCN/PBS) (1:1, v/v, pH 7.4) medium. The probe displayed high specificity toward hypochlorite over other ROS analytes, rapid response to hypochlorite within 30 s, and a broad applicable range of pH 3–8. The detection limit was calculated to be 1.48 μM. Application of this probe for in vitro Hecat cell imaging to detect hypochlorite ions was confirmed. A sensing mechanism based on thioether to sulfoxide oxidation by hypochlorite was proposed and demonstrated. The study presented an effective approach for construction of highly efficient hypochlorite chemosensors from hydrophilic methylthio-substituted coumarins considering their facile access.

Accurate whiteness measurement is critical across various industries including textiles, paper, and detergents. With the advent of fluorescent whitening agents (FWAs), the assessment of whiteness has evolved from simply measuring reflectance to determining the spectral radiance factor (SRF) of materials. While multispectral imaging (MSI) can effectively measure object reflectance and colour, its accuracy is compromised by FWAs that significantly augment spectral reflectance. Thus, reliable whiteness measurement requires the determination of both reflectance and SRF. This article presents the design of a specialised light source equipped with an ultraviolet (UV) filter to provide adjustable illumination within an integrating sphere system. By tuning the position of the UV filter, multispectral images are captured of a fabric under varying UV exposures. These images are subsequently processed and combined to reconstruct full-range visible spectrum information. This approach is shown to achieve high accuracy and spatial uniformity in quantifying the whiteness of textiles using MSI.