Purpose This study aims to focus on intaglio printing and the variety of pigments used in intaglio inks – commonly included and also those for specific applications. Design/methodology/approach Pigments in intaglio inks, as colourants and for hiding, but specifically pigments with functional properties for security inks, have been covered, such as carbon black, cholesteric liquid crystals, magnetite and metallic pigments. Findings Intaglio process is used for diverse applications from textiles to illustrations. As this process results in raised print, it is the preferred printing method for high-value documents. The pigments act as further overt or covert authentication features because of their functional properties, such as magnetism, luminescence and infrared absorption. Originality/value This study gives an overview of intaglio inks and intaglio printing techniques and detailed insight into the pigments used in these inks for their distinctive properties. The types of functional pigments, their synthesis process and structure and working principle are detailed. With rising cases of counterfeiting and fakery, such pigments are becoming increasingly important in security printing inks.

Purpose This study aims to synthesize a coumarin-derived dye and evaluate its application in polyester fabric dyeing, focusing on its potential as a safer alternative to hazardous disperse dyes. By examining the dye’s fastness, fluorescence, thermal behavior and theoretical binding interactions, this research supports more sustainable practices in textile processing. Design/methodology/approach The coumarin dye, 7-diethylamino-3-acetylcoumarin, was synthesized via the Knoevenagel reaction. Polyester fabrics were dyed using this coumarin dye under various conditions, including acidic and alkaline. Dyeing performance was evaluated based on washing, rubbing and light fastness tests, with particular attention to reductive washing for optimal results. The dye’s structural characteristics were analyzed through Fourier transform infrared spectroscopy (FTIR), ultraviolet––visible (UV–Vis) and nuclear magnetic resonance (NMR) spectroscopy. Thermogravimetric analysis assessed thermal stability and degradation behavior. Density functional theory simulations were conducted to elucidate dye–fiber interaction mechanisms at the molecular level. In addition, in vitro cytotoxicity was tested using human skin fibroblast (CCD-1079Sk) cells. Findings The coumarin-derived dye exhibited excellent dye affinity and colorfastness on polyester fabrics, especially in acidic conditions with a 45-minute dyeing process followed by reductive washing. No cytotoxic effects were observed in human skin fibroblast cells, underscoring its potential as a safer alternative to conventional synthetic dyes. UV–Vis spectroscopy confirmed strong absorption properties, making the dye suitable for various textile applications. Research limitations/implications The study focused on polyester fabric; future research should extend the application to other textile types. Moreover, further investigation into aquatic degradation pathways and industrial-scale applicability is needed to fully validate environmental benefits. Practical implications The findings suggest that coumarin-derived dyes could provide a safer and more environmentally friendly alternative to disperse dyes in the textile industry. The successful application of the dye under both acidic and alkaline conditions makes it versatile for use in polyester dyeing, potentially reducing chemical waste and health risks associated with synthetic dyes. Originality/value This study contributes to the growing body of research on sustainable textile dyeing by demonstrating the potential of a coumarin-derived dye for polyester fabrics. Its fluorescence, non-toxic nature, robust fastness properties, eco-friendliness and adaptability to different dyeing conditions make it a valuable alternative to traditional hazardous dyes, supporting the shift toward greener practices in the textile industry.

Purpose The effective removal of harmful dyes from wastewater with green methods is still one of global challenges, and it has attracted great interest. The design and preparation of adsorbent is the core of an adsorption system. From the viewpoint of sustainable development, adsorbents with fewer preparation steps, simpler preparation process, less use of organic solvents are urgently needed and favorable for the adsorption process. In addition, adsorption efficiency is another important factor to be considered. Design/methodology/approach Chitosan metal complex (CTS-Cu) was prepared via a green and facile method with distilled water, and then it was characterized by a series of techniques. Applying the complex, this study was sought to detect the efficacy of removing organic dyes from aqueous solution. Findings The methyl orange (MO) adsorption was significantly affected by adsorption temperature and ionic strength. The adsorption capacity of CTS-Cu for MO was as high as 344.10 mg/g, while that of chitosan (CTS) was 34.14 mg/g at 45°C, indicating the superior advantage of modification and relatively higher affinity of the former adsorbent. It was interesting to find that CTS-Cu exhibited certain adsorption selectivity of MO to methylene blue (MB). However, CTS had certain adsorption selectivity of MB to MO. Research limitations/implications The chitosan–metal complexes with other metals have been prepared. The adsorption behaviors for organic dyes of these materials need further and future investigation. Practical implications CTS-Cu was prepared with distilled water as solvent under room temperature. The costs of CTS and CTS-Cu were relatively low. CTS-Cu could effectively enrich anionic dyes like MO from aqueous solution. Originality/value The preparation process of CTS-Cu was simple and relatively green. The adsorption capacity of CTS-Cu for MO was excellent, and it exhibited certain adsorption selectivity for MO.

Purpose The study aims to synthesize chitosan nano polymers (CSNPs) using ion gelation and load them onto hydroxypropyl cellulose (HPC) polymer to form a CS/HPC nanocomposite to preserve dyed linen textiles. Design/methodology/approach Several examination and analysis methods were used to study the properties of the prepared nanocomposite. For instance, transmission electron microscopy (TEM) was used to measure the diameter of the particles and the morphology of the prepared nanocomposite, and the well-cut diffusion technique in agar was used to evaluate the antimicrobial activity of CS/HPC nanocomposite. The study adopted the experimental approach supported by many examination and analysis methods, such as scanning electron microscopy (SEM), infrared spectroscopy (FTIR), color change value and tensile strength in evaluating the properties of linen textiles treated with CS/HPC nanocomposite. Findings The study showed that the diameter of the prepared nanocomposite particles ranged from 8 to 14 nm. Additionally, it illustrated the high microbial effectiveness of the CS/HPC nanocomposite against the isolated fungal and bacterial strains. The properties of the treated linen textiles were significantly improved, as tensile strength and elongation increased, and the surface morphology improved. FTIR also showed that the functional groups of linen textiles were unaffected by treatment with CS/HPC nanocomposite. Originality/value The novelty of the study is the preparation and use of nanoparticles of natural chitosan polymer by ion gelation method as a sustainable reinforcing and antimicrobial agent of linen textiles.

Purpose This paper aims to realize the possibility of three-dimensional (3D) decorative textures in furniture surface decoration by using the technical characteristics of multilayer deposition and instantaneous curing of UV inks. Design/methodology/approach The size, density and arrangement of the dots in the polka-dot decorative pattern on the surface of the plate should be tested by eye movement to determine the polka-dot pattern that best meets the visual effect of the surface of the furniture product. The surface of the plate is coated with a 3D microdimensional polka-dot decorative texture using UV inkjet printing. The printed polka-dot texture coating is then subjected to a series of tests to assess its adhesion, luster, hardness, abrasion resistance and other physical characterization properties. Findings Results suggest that a more favorable visual impact is achieved with a 4 mm dot diameter and twice the density of the wave point. Through the depositing of the polka-dot pattern with a white ink concentration nine times the average, a solid and vibrant 3D perception is realized. The average height of the coating texture was measured at 164.84 µm, and the gloss was averaged at 2.06. Furthermore, the coating displayed adhesive strength of grade 2 and hardness of 4H, aligning with the application standards for surface paint films on general decorative plates. Originality/value Integrating the 3D polka-dot decorative texture into furniture panels broadens the surface decorative design from two to three dimensions, intensifying the visual and emotional allure of surface decoration for panel furniture products.

Purpose The purpose of this study is to replace synthetic dyes with natural dyes and metal mordants with natural mordants which can result in a complete sustainable dyeing solution. Design/methodology/approach Coloration of textiles using synthetic dyes involves a high concentration of supportive chemicals, which leads to effluent release. Nowadays, there has been great interest in addressing this problem by exploring natural dyes as a potential solution. However, these dyes are applied with metal mordants that may have toxic effects if not removed properly. Findings In this study, the natural dye has been extracted from Sesbania aculeata leaves and applied to silk fabric using lemon juice as a mordant, which has no environmental impact. Dyeing was done with varying dye extract concentration, mordant concentration and dyeing temperature using a meta-mordanting technique. Results indicate that color strength (K/S), rubbing fastness, washing fastness and staining fastness were significantly improved, whereas light fastness showed a slight improvement. Dye exhaustion of 31% was calculated from the absorbance of dye solutions. Originality/value The method explored in this research ensures sustainable development in dyeing by comparing natural and metal mordanting systems. Sesbania aculeata with lemon juice has been explored for the first time for silk, showing good opportunities in sustainable dyeing technology.

Purpose This paper aims to prepare a kind of the UV-curable waterborne polyurethane (UVWPU) and its application in volatility organic compound (VOC)-free advanced water-based varnish. Design/methodology/approach In this paper, a series of UVWPU systems with emulsion stability and excellent film properties were prepared by internal emulsification was obtained from polycarbonate glycol, isophorone diisocyanate and dimethylolpropionic acid as raw materials; acryloyloxy group is introduced through hydroxyethyl methacrylate (HEMA) or pentaerythritol triacrylate (PETA) to obtain photosensitive performance, then neutralized with triethylamine and dispersed with water. A photoinitiator was added to UVWPU, and the coating film was cured by ultraviolet light and the properties were tested. Findings The results show that when the mass ratio of –NCO and –OH was 2.0, the content of dimethylolpropionic acid is 5.5% and the molar ratio of HEMA to PETA is 3.5, solid content of the emulsion is 40% and UVWPU had excellent dispersion performance in water and storage stability. When the photoinitiator is added to the UVWPU emulsion with a mass fraction of 5%, the light curing duration time is 60 s, water absorption of cured film was 8.8%, the adhesion was 0 level, pencil hardness reached 4 H and impact strength is 50 kg·cm, the cured coatings exhibited not only greater hardness, excellent adhesion and excellent mechanical properties but also good thermal stability. The authors successfully obtained a high-performance UVWPU and can meet the requirements of advanced water-based varnish. Research limitations/implications Because of the limitation of experimental conditions, some performances have not been tested. Therefore, researchers are encouraged to conduct further tests. Practical implications The paper established a method to synthesize UVWPU with green surfactants can be used in the coatings, adhesives, finishing agents and so on. Originality/value As an excellent surface treatment material, UVWPU is widely used in wood, construction industry, automobile coating and other fields. The paper provides a method of preparing the UVWPU. A photoinitiator was added to UVWPU, and the coating film was cured by ultraviolet light and the film is uniform and endowed with remarkable heat resistance, high gloss, good fullness and to meet the requirements of VOC-free advanced water-based varnish.

Purpose This study aims to optimize and validate the heat-setting process parameters of cationic dyeable polyester (CDP) knitted fabric to enhance its dimensional stability. Design/methodology/approach The experiments were designed using the Box-Behnken design, with temperature (°C), time (sec) and stretch (%) as key independent variables. The responses analyzed included grams per square meter (GSM), dimensional stability in the course and wales directions and bursting strength of the heat-set knitted fabric. Findings The optimized heat-setting parameters significantly influenced the dimensional stability, GSM and bursting strength of CDP knitted fabric. The optimized heat-setting parameters identified for cationic dyeable interlock knitted polyester are a temperature of 170.5 °C, a time of 90 s and a stretch of 8% in the course direction. GSM decreased primarily with stretch (C), while dimensional stability was mainly affected by temperature (A), time (B) and stretch (C), with minor interactive effects. Bursting strength improved with temperature and time but decreased with excessive stretch. Overall, temperature and stretch played a key role in fabric weight and stability, whereas process time mainly influenced mechanical strength. Originality/value Polyester and CDP exhibit differing thermal responses. While extensive research has been conducted on optimizing the heat-setting process for 100% polyester, studies specifically addressing 100% CDP remain limited. Moreover, previous research on CDP has focused on the effect of adding modifiers with a sulfonate group and their impact on structural changes and thermal properties. This highlights a gap in existing knowledge. This study aims to systematically investigate the influence of these parameters on the dimensional stability, weight of fabric and mechanical properties of 100% CDP interlock knitted fabric.