Coloration Technology最新文献

Detection of defects is an essential quality control method in fabric production. Unsupervised deep learning-based reconstruction algorithms have recently been deeply concerned owing to scarce fabric defect samples, high annotation cost, and deficient prior knowledge. Most unsupervised reconstruction models are prone to overfitting and poor generalisation performance, resulting in blurred images, residual defects, and uneven textures in the reconstruction results. On this account, an unsupervised fabric surface defect detection method using the Progressive Mask Repair Model (PMRM) has been developed. Specifically, PMRM with transformer architecture gathers detailed feature information. In order to pay closer attention to the textural properties of fabrics, the model incorporates structural similarity as a constraint in the training stage. In the detection stage, we designate the non-defective area of the fabric image as the background and the defective area as the foreground. Next, a progressive mask is applied to repair the background of the defective area, which avoids defect false detection resulting from the poor reconstruction effect of the traditional reconstruction model in the non-defective area. Finally, image processing methods such as image difference, frequency-tuned salient detection, and threshold binarisation are used to segment the defects. Relative to the other six unsupervised defect detection methods, the proposed scheme increases the F1 score and intersection over union (IoU) by at least 9.34% and 8.49%, respectively. According to the earlier results, PMRM is effective and exhibits superiority.

A nitrobenzoxadiazole (NBD)-based colorimetric chemosensor CNA (N,N,N-trimethyl-2-(2-(7-nitrobenzo[c][1,2,5]oxadiazol-4-yl)hydrazineyl)-2-oxoethan-1-aminium chloride) was synthesised. The sensor CNA can detect hypochlorite (ClO⁻) via colour variation of yellow to colourless. The detection limit for ClO⁻ by CNA was analysed to be 0.36 μM. Moreover, the naked-eye test strip was successfully applied for ClO⁻ detection. The probing mechanism of CNA to ClO⁻ was proposed to be a hydrolytic cleavage reaction of CNA by ClO⁻ and was demonstrated by electrospray ionisation mass spectrometry (ESI-MS), Fourier-transform infrared (FTIR), proton nuclear magnetic resonance (¹H NMR) analysis and density functional theory (DFT) calculations.

This review concerns the application of disperse dyes to poly(ethylene terephthalate) (PET) fibres using aqueous immersion dyeing processes and the roles of both elevated dyeing temperatures and carriers in such dyeing systems. This part of the paper presents a review of the fundamental properties and characteristics of PET fibres, disperse dyes and dyeing accelerants. In the next part of the paper, the various theories and concepts that have been proposed to explain the promotional effects imparted by elevated dyeing temperatures and carriers to disperse dye uptake on PET and other types of fibre, are reviewed and analysed, from the viewpoints of the essential physico-chemical aspects of both the aqueous disperse dye/PET and disperse dye/carrier/PET systems. Later parts of the paper will present a mechanistic model of the disperse dye adsorption process based on dye solubility as well as a novel plasticisation model of dye diffusion.

Since the water-insoluble dispersing dye has both absorption and scattering characteristics, a spatial resolution hyperspectral measurement approach and experimental testing was proposed in this article, which can collect spectral and spatial data from samples simultaneously. The concentration of 81 groups of three-component disperse dye samples were measured. However, the hyperspectral data of dye solutions in the 420–800 nm band is saturated, resulting in the inability for multispectral data processing. A segmented concentration quantitative analysis model was developed. For the unsaturated band (420–510 nm), the partial least squares (PLS), the N-way partial least squares (NPLS), and support vector machine (SVM) models using the data points on the X-axis of a two-dimensional light intensity distribution map were established. The predicted performance of PLS model was worse slightly than that of the other two models, The coefficient of determination (R²) values of concentrations for red, orange and blue disperse dye were 0.888, 0.796 and 0.959, respectively. For saturated band (520–670 nm), the NPLS and SVM models using the data points on the X- and Y-axis were established. Results shows that the prediction accuracy of concentrations of the three-component disperse dye was increased by adding additional data points on the Y-axis, with R² values of 0.944, 0.807, and 0.912, respectively. For the strong scattering band (680–800 nm), a SVM model was established, and R² of concentration of the three dyes reached 0.974, 0.933 and 0.995, respectively. The results showed that multidimensional spectroscopy method can improve the prediction accuracy of component concentration of disperse dye solution, by using more spectral information from X and Y directions.

The versatility of nanofibres enables them to be used for various technological applications such as filtration, biomedicine and healthcare, composites, protective and functional textiles. Recently, in addition to the functional properties of electrospun nanofibrous mats, their aesthetic properties have been explored. Herein, attempts have been made to develop digital ink-jet printing of regenerated cellulose nanofibrous mats with reactive inks. First, a cellulose acetate polymer was created to fabricate electrospun cellulose acetate nanofibrous mats, which were then converted into regenerated cellulose nanofibrous mats through deacetylation. Next, the cellulose nanofibrous mats were treated with an alkaline solution then coloured with four (cyan, magenta, yellow and black) commercially available reactive inks by a digital ink-jet printing method using a piezoelectric digital ink-jet printer. Various parameters were investigated, including the optimal concentration of the pretreatment agents, fixation temperature and time, colour yield and the absorbency of the electrospun nanofibrous mats. The digital ink-jet printed cellulose nanofibrous mats exhibited excellent colour yield and colour fastness properties. Morphological analysis through scanning electron microscopy and chemical analysis through Fourier Transform–infrared were also carried out.

This study aims to develop microbial indigo reduction by comparing the reducing power between Dietzia sp. KDB1 and yeast (Saccharomyces cerevisiae) at some reduction conditions. Oxidation–reduction potential (ORP), colour strength (K/S), and fluorescence intensity (FI) were applied to evaluate the reduction level as a function of microorganism concentration, pH, and glucose addition at 30°C. For both of the microbial systems, ORP decreased further −20 mV and K/S increased more than two by adding glucose. The reduction level became higher slightly by adding glucose, which played a role of metabolite in both of the reduction systems. Overall, reduction level of the yeast system was about a half of KDB1 system at the same reduction condition of 45 mL volume, 15 g/L natural indigo, 6 g/L reducing agents, pH 10.0, 30°C and glucose added.

The current study provides the first review of alizarin, a natural dye, in terms of its historical aspects and its potential for functional applications in textiles. The review begins with a brief overview of natural alizarin and its occurrence in Rubiaceae family plants, followed by a discussion of alizarin acquisition from its botanical sources through conventional and advanced extraction methods. A special emphasis of this study is on the identification of natural alizarin colourants in archaeological and cultural textiles by using analytical methods based on reflectance, Raman spectroscopy, mass spectrometry and chromatographic profiles. In addition, the functional properties of natural alizarin, including its antimicrobial activity, anti-oxidant activity, insect repellence and ultraviolet protection, are analysed. This paper summarises the methods for obtaining alizarin for coloration, as well as advanced techniques for detecting alizarin in historical textiles, and potential applications of natural alizarin as a functional textile dye.

The discharge of coloured textile printing and dyeing wastewater causes environmental pollution. Disposing of wastewater efficiently, simply and with low consumption, is a problem that must be addressed. Herein, a catalytic method for rapid decolorisation of organic dyes was devised employing a terpyridine iron complex to activate oxidised permonosulphate. CI Acid Red 1 was used as the simulated pollutant, the influences of operating parameters on the fading effects of wastewater were explored. According to the results, the produced catalytic system exhibits a universal catalytic effect. Even when the dye concentration reaches 76.4 mg/L, the dyeing wastewater may be effectively decolorised. In addition, when anions (HCO₃⁻, SO₄²⁻, Cl⁻) were present in the solution, the degradation effect of CI Acid Red 1 was still effective. Interestingly, active species such as sulphate radicals and singlet oxygen were detected in the catalytic degradation system by radical capture experiments. The removal rate of total organic carbon can achieve a percentage of 26.22% in 2 hours. This research provides a unique, enzyme-like catalytic system for the rapid breakdown of dye contaminants.

In the current study, to obtain environmentally friendly printed cotton fabrics with a clear contour edge, ethylene glycol diglycidyl ether (EGDE) as a crosslinking agent and guar gum as a thickener were used with natural madder dye. The solid content of the thickener was assessed to determine the optimal viscosity of the printing paste. Scanning electron microscopy images and colour depth (K/S) values were used to analyse the surface morphology and printing properties. The pattern outline of the printed cotton fabric was assessed with an optical microscope. Also, the overall fastness properties of the printed fabrics were evaluated. The results showed that when the solid content of guar gum was 2.5%, the viscosity of the printing paste was close to 10 000 mPa.s, which was suitable for printing cotton fabrics. Scanning electron microscopy analysis showed that most of the printing paste was removed during the washing process, and did not affect the microstructure of the cotton fabric. Compared with direct printed cotton fabrics, the K/S values of mordant and crosslinked printed cotton fabrics increased by 3.12 and 4.01, respectively. In the optical microscopy photographs, the mordant and crosslinked printed cotton fabrics displayed a clear outline sharpness of the printed pattern, and excellent printed products were obtained. The colour fastness to washing, rubbing and light of the crosslinked printed cotton fabric were significantly improved, reaching levels of 4-5.

The practical application of a sulphur black dye relies on its ability to dye cotton fibres with pure black colour and maintain the colour with high light fastness. Here, we report a synthesis method to prepare a novel water-soluble reactive sulphur black dye. The approach involves the reduction of CI Sulphur Black 1 to its leuco form and subsequent reaction with a water-soluble intermediate containing reactive groups synthesised from amino acid and cyanuric chloride. The optimal carboxyl and reactive group content of the water-soluble reactive sulphur black dye is 141 mmol/100 g, and the water solubility can reach 92 g/L. The fixation of the reactive sulphur black dye on cotton reaches 89% in a pad dyeing process without using sodium sulphate. The reactive sulphur black dye can achieve a light fastness of grade 6-7, a dry rub fastness of grade 4 and a wet rub fastness of grade 2, comparable or higher than the conventional CI Sulphur Black 1. The dyeing results showed that the novel water-soluble reactive sulphur black dye has excellent performance and good application prospects.