Coloration Technology最新文献

Agricultural biomass is a well-known renewable resource with a strong possibility of recycling. The current work focuses on extracting, preparing and colouring Napier grass fibre (NGF) with a colourant extracted from Rubia tinctorum (RT) (which is generally known as madder). NGF that had been water-retted was alkaline scoured and bleached using hydrogen peroxide to increase the material's whiteness index and water absorption capacity without degrading its breaking strength. After being mordanted with tannic acid, the bleached NGF was coloured with an aqueous extract of the colourant extracted from RT. The Box–Behnken response surface methodology design model was employed to optimise the dyeing concentration, temperature and time. The dyed fibre showed good colour strength (K/S) and adequate wash, rub and light fastness. Adopting the findings from the current study would increase the efficient utilisation of biomass for use in textiles, which is unnecessarily wasted.

This review concerns the application of disperse dyes to poly(ethylene terephthalate) fibres using aqueous immersion dyeing processes and the roles of both elevated dyeing temperatures and carriers in the disperse dye/polyester fibre and disperse dye/carrier/polyester fibre dyeing systems, respectively. In this part of the paper, a mechanistic model of the disperse dye adsorption process is presented that is based on the role of dye solubility in disperse dye-PET fibre substantivity. It is shown that the dye solubility model of disperse dye adsorption, which can be articulated using a simple mathematical approach, is able to account for the reasons why elevated dyeing temperatures are utilised in HT dyeing processes, and also why dyeing accelerants enable dyeing to be achieved using lower temperatures of ~100°C.

Digital devices are increasingly being used in the colour measurement of textile-made materials. Proper scanner characterisation is crucial for accurate and consistent colour measurement. In the present study a fuzzy inference system based on subtractive clustering, called FIS_SC method, for the colorimetric characterisation of a scanner to measure the colour of the fabrics in a small region of a colour space is proposed. The results of the proposed method for 16 colour sets were obtained and compared with the results of the scanner characterisation using polynomial regression and neural network method. It was shown that the FIS_SC method successfully characterised the scanner in the small colour space, so that its mean of the colour difference was lower than the polynomial regression and neural network methods in almost all colour sets.

Functional fabrics that are economical and environmentally friendly are desired for many applications. Here in, individual inclusion of different additives, such as softeners, polyurethane, polyethylene glycol (PEG-600) and benzophenone in suitable pigment printing formulation were applied to various cellulose containing fabrics, using flat screen and microwave curing methods. The imparted multifunctional and performance finishes to cellulosic fabrics namely ultraviolet (UV) protection, antibacterial, anti-crease, and softening were evaluated. The developed functional properties and the depth of the pigment prints produced are governed by the nature of the substrate, concentration/location/distribution in addition to fixation of the added active compounds and pigment colourants. The surface alteration, morphological modifications, and immobilisation of the certain active components onto the printed substrates have been confirmed by scanning electron microscopy and energy-dispersive X-ray spectroscopy analysis for selected samples.

Mannich-type dyeing of silk fibroin with aromatic primary amine dyes (APADs) is a novel reactive dyeing method that requires mild conditions and exhibits high selectivity and good wet fastness. However, the primary amine group in the APADs significantly decreases the photostability of Mannich-type dyed silk fabrics. To reveal the structure–activity relationship and photofading mechanism of the APADs by Mannich-type dyeing, six pyrazolone-containing APADs with similar structures were designed and synthesised. Variation in amino electron density among the dye analogues was related to differences in colour fixation of the Mannich-dyed fabrics, as determined from the calculated Mulliken charge densities. Using mass spectrometry to monitor the photodecomposition of the dyed silk, it is demonstrated that the Mannich-type dyed silk fabrics undergo photooxidative fading, in contrast to the conventional acidic-type dyed fabrics that undergo photoreductive fading. Furthermore, it is shown that the Mannich-type dyed silk fabric has a higher light fastness than conventional acidic-type dyed fabrics using the same pyrazolone-containing APADs. Evaluation of dye dipole moment and Mannich-type dyeing shows that the APADs with increased dipole moments generally demonstrated increased light fastness.

Fabric defect detection is a crucial aspect of the textile industry. Currently, deep learning methods have demonstrated exceptional performance in fabric defect detection tasks. However, their performance is greatly affected by the number of defect samples, which is a challenge to obtain during actual production. To address this issue, this article proposes an unsupervised anomaly detection method for fabric defects using image reconstruction networks. This method only requires defect-free samples for training. During the training phase, the model compresses defect-free samples to obtain a low-dimensional manifold and reconstruct them. During the inference phase, the method assesses whether a sample is defective by calculating the reconstruction error between the input and output images, and locates the defect region by computing the difference in various patches. Furthermore, since fabric contains rich texture features, with high correlation between neighbouring pixels, a structure similarity index measure combined with mean absolute error is introduced to evaluate the reconstruction error, which enhances the model's representation ability for defect-free samples. Additionally, considering the diverse texture backgrounds in fabric, a multiscale reconstruction module is designed to optimise the reconstruction effect. Experimental results demonstrate that compared with other related approaches, the proposed method achieves high accuracy (image-based area under the curve (AUC) up to 98.2% and pixel-based AUC up to 97.3%) on multiple datasets and has good generalisation ability for different fabric textures.

Using image extracted colours as the colour source for product colour matching is a common design strategy. The process of colour scheme design involves both source colour combination optimisation and continuous variable optimisation. As a commonly used optimising tool, interactive genetic algorithm (IGA) recombines the colours between alleles, that is, the same area in different colour schemes. Two types of invalid schemes are prone to arise during optimisation. The first is the colour duplication in a colour scheme's areas, which are supposed to be painted differently. The second is the unexpected new colours generated through interpolation between alleles. This article proposes a non-allelic IGA (NA-IGA) method, which allows colour recombination among non-alleles, to avoid invalid schemes and improve algorithm efficiency. The crossover, evaluation, and selection operators are redesigned. NA-IGA tries to maintain the features of extracted colours in the colour schemes while taking user preference into consideration. Thus, interaction methods for colour matching optimisation are designed to extend the evaluation mode of traditional IGA, including colour shuffling, continuous fine-tuning, and so forth. An application test is conducted in the rail vehicle's painting design. The comparison experiment with traditional IGA shows that NA-IGA significantly reduces the generation of invalid schemes and significantly improves efficiency and effectiveness of the optimisation.

The effect of fibre length and grammage on the electrophotographic digital printing process was investigated in this study. While integral optical density values on handsheets have shown no significant change, unprinted handsheets have shown an increasing change as short fibre content has increased. Because of structural changes in the paper surface, the measured results for print chroma, brightness, contrast, and delta gloss differed between paper groups. This research confirmed that these changes have nothing to do with grammage or fibre length content. Regardless of the fibre length ratios, significant increases in tone values of ink, were accompanied by a decrease in the grammage of the handsheets among the grammage groups provided. The specimen grammage affected the universal colour diagrams, but not the fibre length. The discrepancies in all of these printing outcomes were thought to be caused by the random distribution of fibres and the distances between them on the paper's surface.

In the current study, a sequencing batch reactor (SBR), a sequencing batch biofilm reactor (SBBR) and a moving bed biofilm reactor (MBBR) were designed and used to treat actual samples of combined domestic and dye (Congo red) wastewaters over a 10-hour cycle. A new application of reusing plastic bottle caps in the SBBR and MBBR was examined. In the SBR, maximum chemical oxygen demand (COD) removal of up to 66% ± 3% was achieved after nine cycles of operation. In the SBBR, a rapid increase in COD removal efficiency was observed during the first cycle, with a noticeable improvement in performance in subsequent cycles, eventually reaching a maximum COD removal efficiency of 77% ± 3%. In the MBBR, maximum COD removal of up to 88% ± 3% was achieved after nine cycles of operation. The biodegradation occurred during two phases in the SBR and SBBR, as an anaerobic phase in the first 2 hours and then as an aerobic phase in the last 8 hours of operation; the MBBR operated in the fully saturated aerobic phase for 10 hours. Of the three reactors used, results for the MBBR in the fully aerobic condition by using polyethylene terephthalate caps as a biocarrier, demonstrated the optimum conditions under which to treat and biodegrade Congo red at all concentration in each cycle. The maximum removal efficiency, which equalled 99% ± 1%, was recorded at an optimal concentration of 50 mg/L. Additionally, five kinetic models were proposed to assess microbial growth activity, and the results demonstrated the elimination of toxic effects when using polyethylene terephthalate caps as biocarriers in the MBBR. The laboratory experiments were consistent with the Monod model.

Colour fading with laser application has now become a well-known and frequently used process in the denim industry. However, in practice, high strength losses and even tears may occur in the trousers as a result of incorrect or excessive laser application. In this study, the effects of resolution (dpi) and pixel time (μs), which are the two main parameters of laser colour fading, and also the effects of two-passage laser treatments on colour fading and fabric strength were examined statistically and optimum conditions were determined. When the results of the studies are evaluated in general, it can be said that as the resolution (dpi) increases during the laser process, the colour fading effect increases, but when it is above the 31 dpi value, the strength loss increases excessively. As the second important parameter, the pixel time, increased, the colour fading effect increased. When the time exceeds 80 μs, there is a marginal increase in the strength loss value. Furthermore, it was observed that colour fading (%) values increase if laser process is applied in two passages, but in this case also the tear strength loss increases. It can be said that optimising the laser processing conditions in enterprises according to the product type (fibre content, weight, etc.) is a more accurate approach in terms of both the fading performance to be obtained and product quality. For 11.25 ounce trousers made of 95.3% cotton/3.4% polyester (T400)/1.3% elastane used in this study, it can be said that laser application could be made in two passages if necessary for obtaining high colour fading, however it should be noted that resolution and pixel time should not exceed 31 dpi and 80 μs, respectively. Provided that resolution and pixel time does not exceed 31 dpi and 80 μs, respectively, they can be changed depending on the degree of colour fading needed.