Coloration Technology最新文献

Colour has been an indispensable element for humanity from past to present. Colour, which in the past was used only to add visual appeal and to differentiate from others, is now also used for various functional purposes (such as textiles that change colour with heat). The aim of this study is to investigate whether the fabric colour has an effect on the handle perception and warm/cool feeling of the user. Studies have shown that, in subjective evaluations, fabrics with warm colours (yellow, red and orange) cause softer and warmer feeling than those with cool colours (blue, green and purple). In fact, considering that there is no statistically significant difference between the handle and temperature values determined by objective test methods, it can be said that this perception may arise from the psychological effect of colour. All these results reveal that colour, beyond adding visual appreciation to the fabric, also has an effect on handle perception and warm/cool feeling, which play an important role in the purchasing process for customers.

In the modern period, scientists are interested in the functional properties of natural materials. The present study is the first report on the use of safflower (Carthamus tinctorius L.) yellow dye extract combined with chitosan bio-mordant for enhancing the anti-bacterial and ultraviolet-protective activities of silk. The presence of flavonoid-based compounds in the dye extract was verified using liquid chromatography–mass spectrometry, Fourier transform-infrared spectroscopy, and ultraviolet-visible techniques. Moreover, alum mordant was also utilised in the silk dyeing process to compare the efficiency of bio and metallic mordanting agents. Experiment outcomes revealed that the chitosan mordanted-dyed silk sustained adequate fastness after being tested by washing, light, wet-rubbing, and dry-rubbing. In addition, superb bacterial inhibition percentages of 89% and 76% against Escherichia coli and Staphylococcus aureus, individually, were accomplished. Furthermore, the ultraviolet-protective behaviour of this silk sample was demonstrated with a 50+ ultraviolet protection factor and low-grade ultraviolet transmittance. This study reveals the great performance of an organic flavonoid dye as a sustainable and environmentally-friendly substance for dyeing and functionalising silk, as well as the efficacy of a green mordant over a metallic mordant in increasing the dyeability and functional activities of silk.

Cotton/modal blended fabrics are favoured by the market because not only do they have the advantages of the dimensional stability of cotton and drape wear resistance of modal, they also overcome their shortcomings, displaying a sense of stiffness and smooth feel. However, because of the differences in the physical and chemical properties between each component, the dyeing of blended fabrics with reactive dyes is prone to problems such as low fixation percentage, different dyeing percentages and colour depth. Here, two cationic modifiers, 2,3-epoxypropyltrimethyl ammonium chloride (GTA) and methaacryloyloxyethyltrimethyl ammonium chloride (DMC), were applied for cationic modification of cotton/modal blended fabrics, and their role in the dyeability and union dyeing of cotton/modal blended fabrics was studied. The results showed that the K/S and fixation percentage of the blended fabric treated with GTA and DMC cationic agents could be significantly improved compared with the control group, and that the colour fastness of the blended fabric can reach grade 4-5. Compared with GTA, DMC-modified cotton/modal blended fabric showed better union dyeing properties because of its better diffusion performance in the fibre. The mesoporous volume of the cotton fibre is higher than that of the modal fibre, while the micropore volume is the opposite. Consequently, DMC macromolecules, through free radical graft polymerisation, were more likely to diffuse into cotton fibres with more mesoporous content, increased the interaction force between anionic reactive dye and cotton fibre, and improved the dyeability of the cotton component and the union dyeing performance of the blended fabric.

In this study, surface modification of wool fabrics by oxygen plasma was carried out to enhance colour, dyeability and fastness properties. Avocado (Persea americana) seed was selected as the natural dye source, plasma activated wool samples were dyed with the extracted colourant and tartaric acid (10% and 20% owf) was used for simultaneous mordanting. All samples exhibited very good washing and dry rubbing fastness grades. It was observed that plasma treated samples have darker and more saturated colours with a persistent hue and increased wet rubbing fastness grades. Applying plasma treatment and using tartaric acid as bio-mordant provided a noticeable increase in chroma and colour strength, and a slight improvement in fastness to light. Effect of pH of the dye bath on dyeability and the bio-mordant role of tartaric acid were also investigated for four mordant concentrations (2%, 5%, 10% and 20% owf), and it was detected that using 5% owf or higher concentrations of tartaric acid provided different colour characteristics and dyeability when compared to the dye solutions prepared with inorganic acid. Based on findings of the study, it was concluded that modifying the fabric surface by oxygen plasma can be used to enhance the dyeing performance without causing a major change in the characteristic hue of the colourant extracted from avocado seeds. The use of tartaric acid - solitary or accompanied with plasma treatment - to increase the affinity between the colouring matter and the fibre was also recommended.

Textile printing processes consist of the localised application of colour on textile substrates to obtain well-defined designs and patterns. Currently, there are many textile printing techniques; however, the limitations and selectivity of these techniques still keep the printing method of rotary screen printing the most important and used among them. One of the advantages of rotary printing is its excellent application versatility, which can be used for any fabric and non-wovens, fibre, or mixtures, with high production speed, quality, colour fastness, and definition. However, due to its high complexity, rotary printing requires great technical knowledge. Rotary printing requires specific application care depending on the fabric structure, fibrous composition, grammage, and type of intended effect. Regardless of the technique used, printed articles need to ensure that the colour remains attached to the substrate, either by direct dye–fibre or indirect pigment–binder–fibre bonding, to resist the conditions of use, that is, light, abrasion, stretching, and washing. The rise in recent publications reflects the search for economic and sustainable textile printing alternatives, focusing on screen printing variables. Based on this, this review aimed to present a comprehensive guide containing all the care and essential technical information for processes based on rotary printing.

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.