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This paper proposed the inkjet head and the equipment. To realize high resolution printing with QD ink, we had to overcome the problem of robust inkjet head for QD particles. We proposed the inkjet head to eject high viscosity ink and the ink circulation system to avoid aggregation. Also, we proposed the DPN technology for high resolution printing. By combining the inkjet head technology and the equipment technology, we demonstrated QD color converter‐type Micro LEDs display panels. [ABSTRACT FROM AUTHOR]

A passive, low‐cost, paper‐based intelligent reflecting surface (IRS) is designed to reflect a signal in a desired direction to overcome non‐line‐of‐sight scenarios in indoor environments. The IRS is fabricated using conductive silver ink printed on paper with a specific nanoparticle arrangement, yielding a cost‐effective paper‐based IRS that can easily be mass‐produced. Full‐wave numerical simulation results were consistent with measurement results, demonstrating the IRS's ability to reflect incident waves into a desired nonspecular direction based on the inkjet‐printed design and materials. [ABSTRACT FROM AUTHOR]

Cobalt ferrite (CFO), barium titanate (BTO) core-shell nanoparticles (CFO:BTO NPs) exhibit multiferroic properties through the magnetoelectric effect. Inkjet printing is a direct-write, additive manufacturing technique for fabrication of electronic components and devices. Hansen Solubility Parameters (HSP) are a practical tool to understand solution and dispersion behavior of materials in a mixture. This work applies HSP analysis to improve CFO:BTO NPs synthesis and guide the ink formulation process. The estimated HSP values for CFO:BTO core-shell NPs (dD = 15.5, dP = 11.9, dH = 23, r = 4.6), CFO (dD = 15.9, dP = 10.6, dH = 22.5, r = 4.9), and BTO (dD = 16.6, dP = 9.7, dH = 15.4, r = 5.8) are analyzed. Limits and considerations of the HSP are discussed and results are combined with solvent thermal and fluid properties to develop ink formulations for multi-functional, multi-material inkjet printing applications. [ABSTRACT FROM AUTHOR]

Wastewater management is of considerable economic and environmental importance for the dyeing industry. Digital textile printing (DTP), which is based on sublimation transfer and does not generate wastewater, is currently being explored as an inkjet-based method of printing colorants onto fabric. It finds wide industrial applications with most poly(ethylene terephthalate) (PET) and nylon fibers. However, for additional industrial applications, it is necessary to use natural fibers, such as cotton. Therefore, to expand the applicability of DTP, it is essential to develop a novel reactive disperse dye that can interact with the fabric. In this study, we introduced a blocked isocyanate functional group into the dye to enhance binding to the fabric. The effect of sublimation transfer on fabrics as a function of temperature was compared using the newly synthesized reactive disperse dyes with different blocking groups based on pyrazole derivatives, such as pyrazole (Py), di-methylpyrazole (DMPy), and di-tert-butylpyrazole (DtBPy). Fabrics coated with the new reactive disperse dyes, including PET, nylon, and cotton, were printed at 190 °C, 200 °C, and 210 °C using thermal transfer equipment. In the case of the synthesized DHP-A dye on cotton at 210 °C, the color strength was 2.1, which was higher than that of commercial dyes and other synthesized dyes, such as DMP-A and DTP-A. The fastness values of the synthesized DHP-A were measured on cotton, and it was found that the washing and light fastness values on cotton are higher than those of commercial dyes. This study confirmed the possibility of introducing isocyanate groups into reactive disperse dyes. [ABSTRACT FROM AUTHOR]

The application of UV digital inkjet printing onto melamine-faced board (MF) has attracted increasing attention as an efficient and environmentally benign surface decoration method. However, the interface bonding between UV coating and melamine-formaldehyde surface is weak, resulting in poor printing durability. In this study, the MF surface is grafted with 3-(triethoxysilyl) propyl isocyanate (ICPTES) via a urea cross-linking process, and then condensed with γ-methacryloxypropyl trimethoxy silane (KH570) to improve its compatibility with the polyacrylate-based UV ink. A combination of physical (surface polishing) and chemical (dual-silane treatments) activations of MF surface enhances its interface bonding strength with UV coating up to 2.24 MPa, 966.7% and 119.6% higher than those of the untreated and the conventional adhesion promotor treated surface, respectively. FTIR results confirm that effectual chemical bonds are established between MF surface and UV coating by the ICPTES and KH570 dual-silane treatments. SEM imaging shows that a seamless connection between MF and UV coating forms. Thus, MF surface modified by silane is a facile and effective strategy to enhance the adhesion of UV digital ink and this printing method shows enormous potentials in a wide range of applications. [ABSTRACT FROM AUTHOR]

Light‐driven 3D printing can empower the liberty of creation and concretize the original creation in versatile conditions with plenty of choices in resolution or properties. However, photopolymerization‐based 3D printing inks are facing a trade‐off between requiring processing rate and satisfying performance, and a chemical optimization strategy is proposed to achieve the ink demands of rapid direct ink writing utilizing up‐conversion assisted photopolymerization. Since acylphosphonate can generate two reactive radicals and tertiary amine can reinitiate polymerization in oxygen inhibition, the yielded active species in limited irradiation of 3D printing are maximized to accelerate the polymerization by theoretically and experimentally interpreting the roles of up‐conversion particle, photoinitiators, and co‐initiator played in printing. High print speed in depositing and in situ curing (3.56 × 104 mm3 h−1) are realized, and the manufacturing time is shortened by multi‐resolution printing which is impressive compared to current 3D printing methods. The strategy is simultaneously compatible with rigid and elastomeric materials, and will surely contribute to other light‐driven 3D printing technologies for extensive applications. [ABSTRACT FROM AUTHOR]

One of the major applications (40% in Europe) of plastic is packaging, which is often printed to display required information and to deliver an attractive aesthetic for marketing purposes. However, printing ink can cause contamination in the mechanical recycling process. To mitigate this issue, the use of surfactants in an alkaline washing process, known as de-inking, has been employed to remove printing ink and improve the quality of recyclates. Despite the existence of this technology, there are currently no data linking the de-inking efficiency with typical printing ink compositions. Additionally, it is necessary to investigate the de-inking process under the process parameters of existing recycling plants, including temperature, NaOH concentration, and retention time. This study aims to evaluate the performance of commonly used printing inks with different compositions under various washing scenarios for plastic recycling in conjunction with different de-inking detergents containing surfactants or mixtures of surfactants. The results indicate that the pigments applied to the ink have no significant effect on the de-inking process, except for carbon black (PBk 7). Nitrocellulose (NC) binder systems exhibit high de-inkability (over 95%) under the condition of 55 °C and 1 wt.% NaOH. However, crosslinked binder systems can impede the de-inking effect, whether used as a binder system or as an overprint varnish (OPV). The de-inking process requires heating to 55 °C with 1 wt.% NaOH to achieve a substantial effect. Based on the findings in this work, breaking the Van der Waals forces, hydrogen bonds, and covalent bonds between the printing ink and plastic film is an essential step to achieve the de-inking effect. Further research is needed to understand the interaction between surfactants and printing inks, enabling the development of de-inkable printing inks and high-performance surfactants that allow for de-inking with less energy consumption. The surfactant and NaOH have a synergistic effect in cleaning the printing ink. NaOH provides a negative surface charge for the adsorption of the cationic head of the surfactant and can hydrolyze the covalent bonds at higher concentrations (>2 wt.%). [ABSTRACT FROM AUTHOR]

This study explores the potential benefits of combining different printing techniques to improve the production of flexible printed sensors, which is a relevant application for modern coating and surface design. The demand for cheap, flexible, precise, and scalable sensors for wearable electronics is increasing, and printed electronics techniques have shown great potential in meeting these requirements. To achieve higher performance and synergy, the paper introduces the concept of hybrid printing of electronics by combining aerosol jet printing and screen printing. This multi-process approach allows for large-scale production with high printing precision. The study prepares hybrid connections on a flexible substrate foil for use in flexible printed sensor manufacturing. The research team tests different combinations of printed layers and annealing processes and finds that all prepared samples exhibit high durability during mechanical fatigue tests. Surface morphology, SEM images, and cross-section profiles demonstrate the high quality of printed layers. The lowest resistance among the tested hybrid connections obtained was 1.47 Ω. The study's findings show that the hybrid printing approach offers a novel and promising solution for the future production of flexible sensors. Overall, this research represents an interdisciplinary approach to modern coating and surface design that addresses the need for improved production of wearable electronics. By combining different printing techniques, the study demonstrates the potential for achieving high-volume production, miniaturization, and high precision, which are essential for the ever-growing market of wearable sensors. [ABSTRACT FROM AUTHOR]

The contradiction between the growing demand from consumers for "nutrition & personalized" food and traditional industrialized food production has consistently been a problem in the elderly diet that researchers face and discuss. Three-dimensional (3D) food printing could potentially offer a solution to this problem. This article reviews the recent research on 3D food printing, mainly including the use of different sources of protein to improve the performance of food ink printing, high internal phase emulsion or oleogels as a fat replacement and nutrition delivery system, and functional active ingredients and the nutrition delivery system. In our opinion, 3D food printing is crucial for improving the appetite and dietary intake of the elderly. The critical obstacles of 3D-printed food for the elderly regarding energy supplements, nutrition balance, and even the customization of the recipe in a meal are discussed in this paper. By combining big data and artificial intelligence technology with 3D food printing, comprehensive, personalized, and customized geriatric foods, according to the individual traits of each elderly consumer, will be realized via food raw materials-appearance-processing methods. This article provides a theoretical basis and development direction for future 3D food printing for the elderly. [ABSTRACT FROM AUTHOR]

Recent advances in pigment production resulted in the possibility to print with RGBW primaries instead of CMYK and performing additive color mixing in printing. The RGBW pigments studied in this work have the properties of structural colors, as the primary colors are a result of interference in a thin film coating of mica pigments. In this work, we investigate the angle-dependent gamut of RGBW primaries. We have elucidated optimal angles of illumination and observation for each primary ink and found the optimal angle of observation under diffuse illumination. We investigated dot off dot halftoned screen printing with RGBW inks on black paper and in terms of angle-dependent dot gain. Based on our observations, optimal viewing condition for the given RGBW inks is in a direction of around 30°C to the surface normal. Here, the appearance of the resulting halftoned prints can be estimated well by Neugebauer formula (weighted averaging of the individual reflected spectra). Despite the negative physical dot gain during the dot off dot printing, we observe angularly dependent positive optical dot gain for halftoned prints. Application of interference RGBW pigments in 2.5D and 3D printing is not fully explored due to the technological limitations. In this work, we provide colorimetric data for efficient application of the angle-dependent properties of such pigments in practical applications. [ABSTRACT FROM AUTHOR]

To maximize the potential of 3D printing, several technological issues must be overcome, especially in the case of semisolid extrusion (SSE), where the 3D model is built up through the well‐defined extrusion of polymeric ink. Focusing on natural polymers, their physicochemical properties should be deeply investigated to evaluate 3D printability. This study aims to produce tablets easy to swallow, exploiting as 3D printing ink a crosslinked alginate hydrogel added of sorbitol, speculating that the plasticising action of sorbitol should allow to improve tablets' swallowability. Three different amounts of 70% sorbitol solution (5%, 15%, 25% v/v) are evaluated to identify the best composition in terms of both printing and technological properties. The data obtained from the chemical, rheological, and mechanical evaluation of each ink are related to the printing performance, to reach the best manufacturing reproducibility. Linear regression fitting study (r2 = 0.9982) confirms the predictable relationship between residual mass of final platforms and sorbitol amount loaded. To characterize the final products, all dried batches are subjected to technological evaluation highlighting differences in the matrix softability as well as in the swelling/erosion properties after the interaction with biological fluids. [ABSTRACT FROM AUTHOR]

Interest in moving from 3D printing to 4D printing, which would enable rapid and precise motion in reaction to a given stimulus, is evolving. Thermally responsive hydrogels are one of the most common types of soft 4D devices. They are capable of changing shape or behavior autonomously in a manner resembling natural movement, and a bio‐inspired soft actuator has been fabricated by combining stimuli‐responsive nanoparticles with 3D printable hydrogels. We formulated and tested an N‐isopropylacrylamide (NIPAm) and polyethylene glycol thiol‐coated gold nanorod (P‐AuNR) hydrogel nanocomposite as an active ink material for use in the fabrication of heat‐sensitive soft actuators for photo‐responsive soft robotic motions. Due to their surface plasmon resonance (SPR), those highly dispersible P‐AuNR was able to absorb near‐infrared (NIR) light and release heat into their surroundings. This system was not immersed in water and reacted quickly and sensitively to NIR exposure. The 3D structure designed and fabricated with these inks was able to deform selectively only in a very localized part in response to non‐contact external stimuli, leading to various types of controlled shape‐morphing. [ABSTRACT FROM AUTHOR]

Thermochromic inks (TC) have received increasing attention in recent years, particularly in the design and packaging industries. Their stability and durability are crucial for their application. This study highlights the detrimental effects of UV radiation on the lightfastness and reversibility of thermochromic prints. Three commercially available TC inks with different activation temperatures and in different shades were printed on two different substrates, cellulose and polypropylene-based paper. Used inks were vegetable oil-based, mineral oil-based and UV-curable. The degradation of the TC prints was monitored using FTIR and fluorescence spectroscopy. Colorimetric properties were measured before and after exposure to UV radiation. The substrate with a phorus structure exhibited better colour stability, suggesting that the chemical composition and surface properties of the substrate play a crucial role in the overall stability of thermochromic prints. This can be explained by the ink penetration into the printing substrate. The penetration of the ink into the structure (cellulose fibres) protects the ink pigments from the negative effect of the UV radiation. Obtained results suggest that although the initial substrate may appear suitable for printing, its performance after ageing may not be optimal. In addition, the UV curable prints show better light stability than those made of mineral- and vegetable-based inks. In the field of printing technology, understanding the interplay between different printing substrates and inks is critical to achieve high-quality, long-lasting prints. [ABSTRACT FROM AUTHOR]

Modern logo design is characterized by its ability to convey information through the use of various images and text compositions. These designs often use simple elements such as lines to capture the essence of a product. When using thermochromic inks in logo design, it is important to consider their composition and behavior, as they differ significantly from conventional printing inks. This study aimed to determine the resolution capabilities of the dry offset printing technique when using thermochromic ink, with the ultimate goal of optimizing the thermochromic ink printing process. Horizontal and vertical lines were printed using both thermochromic and conventional inks to compare the edge reproduction characteristics of the two ink types. Moreover, the impact of the type of applied ink on the share of mechanical dot gain of the print was investigated. Additionally, modulation transfer function (MTF) reproduction curves were generated for each print. Moreover, scanning electron microscopy (SEM) was conducted to investigate the surface of the substrate and prints. It was found that the quality of the printed edge produced by thermochromic inks can rival that of conventional inks. Thermochromic edges showed lower raggedness and blurriness values for horizontal lines, whereas line orientation proved to be insignificant in the case of vertical lines. MTF reproduction curves confirmed higher spatial resolution for vertical lines in the case of conventional inks, whereas they were identical for horizontal lines. The share of mechanical dot gain is not highly influenced by the ink type. SEM micrographs confirmed that the conventional ink smooths out the micro-roughness of the substrate. However, on the surface, the microcapsules of thermochromic ink (measuring 0.5–2 µm) are observable. [ABSTRACT FROM AUTHOR]

Inkjet printing is a popular technique for depositing high-precision ink lines. This study reports the printing parameters' influence on the electrical properties of the sensing devices. The electrochemical sensors are fabricated with a commercial piezoelectric printer and silver ink. Different substrates are evaluated in the printing process, including paper, polyimide, and polyvinyl chloride (PVC) tapes. Ink depositions' temperature, ink drop spacing, length, and the number of the ink layer are also evaluated in this study. Higher temperatures (40 °C) make the substrate surface smoother, improving the printing quality. Controlling the ink drop spacing produces narrow continuous ink lines. The number of ink layers changes the film thickness, altering their electroactive surface area. The best printing parameters are PVC tape at 40 °C, 17 µm drop spacing, one layer, and 13 mm length. Under optimized conditions, three-electrode electrochemical systems are fully printed with silver ink, showing batch-to-batch reproducibility (RSD = 3%). Their analytical performance is evaluated for picric acid, hydrogen peroxide, and glucose quantification. The sensors are modified with glucose oxidase to quantify glucose in artificial saliva, confirming their analytical applicability. Therefore, this work reports fundamental aspects of inkjet printing, bringing valuable findings to guide new research involving inkjet-printed electrochemical biosensors/sensors ((bio)sensors). [ABSTRACT FROM AUTHOR]

In this paper, a MOD (Metal organic decomposition) Al doped ZnO (AZO) ink was directly used for inkjet printing transparent and conductive AZO films. The ink was synthesized by using zinc acetate dihydrate and aluminum nitrate nonahydrate as precursor, 1,2-diaminopropane as a complexing agent, ethyl alcohol as solution, ethyl cellulose as addition agent. The thermal decomposition behavior of the MOD ink was investigated. The various MOD AZO inks were inkjet printed and heated at different temperatures for different times. The films were studied by X-ray diffraction, scanning electron microscopy, resistivity measurements and ultraviolet–visible spectroscopy. The results demonstrated that 0.2 M AZO (2 at%) film heated at 250 °C for 120 min showed highly preferential growth along the c -axis, uniform microstructure with a resistivity of 0.03 Ω cm and high transmittance more than 90% in the visible range of the spectrum with an optical band gap at 3.326 eV. [ABSTRACT FROM AUTHOR]

The direct-ink-writing (DIW) has been widely used to print various functional devices using different self-leveling inks. Due to the complicated rheological behavior and multiple processing parameters, how to rapidly determine the crucial parameter for high-precision printing is still challenging. Here we adapt a widely used commercial silver paste and identify the critical parameter for dominating the flatness through observation of the microstructure evolution for the line-to-layer forming process. An analytical model for flatness with printing parameters was established. Using the proposed model, the printing process parameters for achieving high flatness can be directly determined, avoiding the high cost of extensive experimental exploration. [ABSTRACT FROM AUTHOR]

Currently, there is a shortage of pediatric medicines on the market, and 3D printing technology can more flexibly produce personalized medicines to meet individual needs. The study developed a child-friendly composite gel ink (carrageenan-gelatin), created 3D models by computer-aided design technology, then produced personalized medicines using 3D printing to improve the safety and accuracy of medication for pediatric patients. An in-depth understanding of the printability of different formulations was obtained by analyzing the rheological and textural properties of different gel inks and observing the microstructure of different gel inks, which guided the formulation optimization. Through formulation optimization, the printability and thermal stability of gel ink were improved, and F6 formulation (carrageenan: 0.65%; gelatin: 12%) was selected as the 3D printing inks. Additionally, a personalized dose linear model was established with the F6 formulation for the production of 3D printed personalized tablets. Moreover, the dissolution tests showed that the 3D printed tablets were able to dissolve more than 85% within 30 min and had similar dissolution profiles to the commercially available tablets. This study demonstrates that 3D printing is an effective manufacturing technique that allows for flexible, rapid, and automated production of personalized formulations. [ABSTRACT FROM AUTHOR]

Mechanofluorochromic materials that render sensitive fluorescence color/pattern change upon mechanical stimuli have drawn extensive attention. However, traditional mechanofluorochromism relies on the chemical transformations of mechanophores, but their types are quite few. It remains challenging to develop mechanofluorochromic materials with customized fluorescence color changing response. Herein, a generally applicable strategy is proposed to present a class of double-layer mechanofluorochromic hydrogels based on the facile integration of two different-colored fluorescent hydrogels. Due to the UV transmittance change of top layer under Poisson's effect, the emission intensity ratio of the upper and lower hydrogels exhibits a strain-dependent change, resulting in a force-triggered overlapping color variation. Both the UV transmittance of top layer and the fluorescence emission of bottom layer can be readily modulated to enrich the variety of mechanofluorochromism. Besides, the bottom layer is available to be printed by ion inks to fabricate patterned double-layer fluorescent hydrogel, holding great potential to design flexible mechanofluorochromic platforms for smart display and information encryption. [ABSTRACT FROM AUTHOR]

Fluorescent anti-counterfeit printing technology is applied in the special fluorescent printing ink used for logos, which in conjunction with additional light excitation to expose the encrypted information play an anticounterfeiting role. Fluorescent anti-counterfeiting is mostly used in film or solid state; therefore, it is necessary for fluorescent ink to have strong luminescent properties in both states. Aggregation-induced emission (AIE) molecules are a class of molecules that emit weak or even no light in a single molecule state and exhibit strong luminescence in an aggregated state. As a typical AIE molecule with simple synthesis and high fluorescence intensity, the salicylaldehyde Schiff base molecule has a stimulus-responsive fluorescence mechanism. Its different fluorescence characteristics in acid-base environments make this kind of molecule outstanding in the field of anti-counterfeit printing. In this study, the salicylaldehyde Schiff base AIE molecule was prepared by a one-step nucleophilic addition reaction of salicylaldehyde and amine, and its application in anti-counterfeit printing was further demonstrated. Through the characterization of the molecule in different environments, the role of its AIE characteristics and stimulus response fluorescence mechanism in anti-counterfeit printing applications was elucidated. The experimental raw materials are easy to obtain, safe, low cost, and the required instruments are routine, which meets the requirements of laboratory teaching. Through this experimental training, students not only master the preparation method of Schiff base compounds, but also learn the application of stimulus response fluorescence of salicylaldehyde Schiff base molecules in anti-counterfeit printing. The combination of classroom teaching and extended reading, enables students to further understand the characteristics of anti-counterfeit printing products and design concepts. [ABSTRACT FROM AUTHOR]

Bis(2-ethylhexyl) phthalate (DEHP) is a plasticizer that has been massively used since the second part of the twentieth century by the plastic industry to provide softness properties to PVC. This chemical is considered as toxic to reproduction and endocrine disrupting, and a wide range of uses are now forbidden by the EU. Despite these regulations, DEHP is still found to be a widespread contaminant in watersheds in the EU. In this study, we calculate retrospective and prospective scenarios of past and future emissions of DEHP in the environment (water, soil, air) in the EU 28, taking into account the entire lifecycle of the substance, from its production and its inclusion in polymer (mainly PVC) and non-polymer products (adhesive and sealant, ceramic and printing ink) to the recycling and end of life of these products. We develop a stock and flow model based on dynamically estimating the stocks of DEHP present in products on the market. Our results show that the introduction of recent regulations to limit the use of DEHP (that bring a 70% reduction of DEHP contained in products placed on the market in 2020 and 75% in 2040) will not reduce significantly future emissions. This persistence of emissions is explained by the high stocks built in the economy and the long-term presence of soft PVC waste in landfills. Our results suggest that DEHP will remain a cause of environmental contamination many decades after uses have declined and even ceased, and it appears to be too late for market regulation at the market stage to offset the effect of past stock buildup and landfilling. It is likely that several chemicals that are not considered as persistent and therefore not the focus of international regulations could exhibit the same characteristics. Regulations should avoid possible use patterns that make hazardous chemicals persistent in products, because they have the potential to create long-term and almost irreversible environmental pollution and impacts. [ABSTRACT FROM AUTHOR]

The printing ink on the plastic surface will greatly reduce the quality of recycled plastic products. In this work, quaternary ammonium-modified waste cooking oil (WCOEQ) was fabricated using waste cooking oil, epichlorohydrin, and trimethylamine aqueous solution as raw materials, through ring-opening esterification and quaternary amination reaction. The synthesis conditions of WCOEQ were optimised, and the structure and properties of WCOEQ were characterised by Fourier transform infrared spectroscopy, zeta potential, and 1H NMR. Furthermore, WCOEQ had excellent emulsifying performance, low kraft point, low critical micelle concentration value, good foaming, and stability, which could effectively reduce the surface tension of water, showing application potential in the field of plastic deinking. Importantly, compared with the waste cooking oil without deinking effect, the WCOEQ had an excellent deinking performance on the ink on the plastic surface, and the deinking efficiency could be improved by increasing the concentration of the deinking agent, the deinking temperature, and prolonging the pre-soaking and stirring time. The results of atomic force microscope, energy-dispersive spectroscopy, optical photos, and Leica microscope showed that the roughness changed significantly and the ink molecules were gradually peeling off. This work highlighted the potential of quaternary ammonium-modified waste cooking oil for excellent removal of printing inks on the plastic surface. [ABSTRACT FROM AUTHOR]

Combining liquid fluidity and metallic conductivity, gallium–indium (Ga–In) alloys are making a splash in areas such as stretchable electronic circuits and wearable medical devices. Due to high flexibility, direct ink write printing is already widely employed for printing Ga–In alloys. Currently, pneumatic extrusion is the main method of direct ink write printing, but the oxide skin and low viscosity of the Ga–In alloys make it challenging to control after extrusion. This work proposed a method for direct ink write printing of Ga–In alloys utilizing micro-vibration-driven extrusion. Micro-vibration reduces the surface tension of Ga–In alloy droplets and avoids the appearance of random droplets during printing. Under micro-vibration, the nozzle tip pierces the oxide skin to form small droplets which have a high moldability. The droplet growth process is significantly slowed down by optimizing suitable micro-vibration parameters. Therefore, the Ga–In alloy droplets with high moldability can be maintained at the nozzle for a long period, which improves printability. Furthermore, better printing outcomes were obtained with micro-vibrations by choosing the proper nozzle height and printing speed. Experiment results demonstrated the superiority of the method in terms of Ga–In alloys extrusion control. With this method, the printability of the liquid metals is enhanced. [ABSTRACT FROM AUTHOR]

3D printing is gaining prospects thanks to the ease of manufacturing energy storage devices with programmable geometry at the macro‐ and microscales. Herein, a direct ink writing 3D printing approach for preparing all‐printed flexible micro‐supercapacitors is demonstrated using rationally designed poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS)/MXene composite gels as inks without the tedious processes and toxic organic additives. Among the printable inks, the homogeneously distributed MXene nanosheets can boost the printability of PEDOT:PSS solution and also regulate the interconnected electronic structures of the PEDOT:PSS undergoing a micellar to linear structure transition. The resulting 3D printed micro‐supercapacitors and integrated devices can deliver exceptionally large areal capacitances, remarkable rate performance, and high cycling stability with thickness‐independent capacitances even under exceptional deformations and low temperatures. This study thus provides a simple yet environmental‐friendly approach for preparing the conducting‐polymer‐based inks for 3D printing of customized, multiscale, and integrated energy devices. [ABSTRACT FROM AUTHOR]

In the last decade, 3D printing systems have greatly evolved both in terms of processable materials and printing resolutions, becoming a top seed technology for many academic and industrial applications. Nevertheless, manufacturing polymeric materials characterized by a trabecular porosity and functionally graded architecture—where both the local porosity and chemical composition of the matrix change in the 3D space—through additive platforms remains an open technical challenge. In this study, a 3D extrusion printing strategy to tackle this problem is presented. The proposed systems are based on a flow‐focusing microfluidic printing head—to continuously generate oil‐in‐water emulsion inks—and on an agarose fluid–gel used as a temporary support bath for the deposition of the photo‐curable emulsion inks. It is demonstrated that through this strategy one can design a priori and build with high accuracy both discontinuous and continuous functionally graded polymeric foams, where both the density and composition of the materials could be varied independently within arbitrarily complex 3D architectures. This study provides new means for the synthesis of microporous, polymeric FGMs which could find applications ranging from interface tissue engineering to automotive and construction industries. [ABSTRACT FROM AUTHOR]

Gravure printing is widely used in food, pharmaceutical, and other packaging industries. As a green printing material, water-based ink has problems such as non-volatile and poor drying on non-absorbent packaging substrates, which has a great impact on its application. To solve these difficulties, this study adopts the volume of fluid (VOF) method and user-defined function (UDF) to establish a multiphase flow impinging air jets drying model of water-based ink in the gravure printing process, taking a water-based ink droplet as an example. The model was used to simulate the ink drying state in the impinging air jets region and analyze the effects of impinging air jets' temperature and velocity, as well as ink viscosity and thickness, on the ink drying efficiency. Meanwhile, the heat and mass transfer mechanism between impinging air jets and water-based ink was investigated. The results show that the higher impinging air jet temperature and velocity, the faster the drying rate of the ink; a lower viscosity and thinner thickness of ink can also enhance the drying efficiency of the ink. The multiphase impinging air jets drying model based on the computational fluid dynamics (CFD) method provides a new research idea for the analysis of drying characteristics of water-based ink on non-absorbent substrates, and the research results provide theoretical support to promote its application. [ABSTRACT FROM AUTHOR]

Featured Application: Wearable Antenna Technology. Screen-printed and inkjet-printed conductive fabric antennas have been investigated in this manuscript. The former showed optimal radiation performance after fabrication and measurement, which was the basis for developing a new fabric antenna feeding technique. The aperture-fed technique is achieved with a single coaxial cable overlayed on a cut-out slot on the ground layer of the patch antenna. The cable is connected with conductive silver-based epoxy paste with high resilience to mechanical stress. Two antenna models for Bluetooth low energy (BLE) and long-range (LoRa) wireless applications were designed, fabricated, and measured at 2.44 GHz and 868 MHz, respectively, with good impedance and radiation performance. The measured antennas operated from 2.4 to 2.48 GHz (BLE) and 853 to 886 MHz (LoRa) at −10 dB S11. Measured results also showed a 56% radiation efficiency at BLE and 44.9% at LoRa. The screen-printing procedure and feeding technique have been presented in this manuscript. [ABSTRACT FROM AUTHOR]

This research explores the interactions of tripolyphosphate-chitosan-pea protein (TPP-CS-PP) in improving the stability and storage of 3D printing food inks. Chitosan (CS) and pea protein (PP) were complexed at various concentrations with 80 % palm olein to produce high internal phase Pickering emulsions (HIPPEs) 3D printing food inks. The resulting CSPP HIPPEs exhibited shear-thinning behaviour and the flexibility to switch between solid and liquid states, ideal for 3D printing. CSPP1:150 achieved the best 3D printing resolution and shape fidelity due to electrostatic attraction of CS-PP and excess PP enhancing adhesion at the oil/water interface. After spraying tripolyphosphate (TPP), crosslinking with CS and phosphorylation of PP further improved HIPPE resistance to deformation and oiling off for 2 days post-printing. This is a significant improvement over the control. Thus, further investigation on the interaction of TPP with CS and PP is warranted to further improve the storage stability of 3D printed food inks. [Display omitted] • Increasing PP/CS ratio improves 3D print resolution. • TPP spray extends HIPPE shelf-life post-printing by 2 days at room temperature. • CS-PP-TPP interaction contributed towards longer storage capacity of HIPPE. [ABSTRACT FROM AUTHOR]

The elderly face malnutrition and dysphagia. 3D printing with high-protein surimi offers an innovative way to customize nutrition and texture of foods for the elderly. This study explored whether tilapia-based surimi ink (TBSI) with Ulva powder (UP, 0–3 %) could improve physicochemical properties and printability as an alternative to traditional pollock-based surimi ink (PBSI). TBSI showed a more uniform microstructure, greater water-holding capacity (WHC), and better printability with consistent extrusion than PBSI. Adding UP to TBSI promoted cross-linking and enhanced microstructure and WHC. Rheological analysis revealed that all inks exhibited shear-thinning behavior. UP increased complex viscosity, storage modulus, and loss modulus. Notably, UP above 2 % improved protein matrix uniformity, structural integrity, and printability, as confirmed by FT-IR and 3D printing tests. The hardness of steamed TBSI fish cake increased when infill density increased. This study highlights the potential of TBSI with UP for 3D printing to prepare personalized and elderly-friendly food. [Display omitted] • Tilapia-based surimi ink (TBSI) offers superior printability for 3D printing. • TBSI matches pollock-based ink in protein and has superior water-holding capacity. • Adjusting infill density in 3D printing effectively controls product hardness. • Ulva powder, especially above 2 %, improves print performance with kept hardness. [ABSTRACT FROM AUTHOR]

[Display omitted] • A photo-responsive HIPPEs with 96% internal oil phase were tolerant to pH variations (pH = 2~12). • The microstructure of porous materials was regulated by UV irradiation. • A color-changing writing ink for 4D printing was obtained without any additives. High internal phase Pickering emulsions (HIPPEs) have attracted increased interest due to their diverse applications in fields such as food and material science. The pH value may vary in different application fields; however, maintaining the stability of HIPPEs at various pH levels presents a notable challenge. Here we describe photo-responsive HIPPEs tolerant to different pH values (pH = 2–12) with up to 96 % internal phase through one-step emulsification without pre-treatment (such as ultrasonic dispersion). The emulsifier was formed by the host–guest interaction between chitosan-grafted cyclodextrin (CS-CD) and azobenzene (C 4 AzoC 6 N). The microstructure of the porous materials prepared from the HIPPEs can be regulated by the photo-triggered adsorption of supramolecular polymers at the oil–water interface. Moreover, due to the photochromism properties of C 4 AzoC 6 N, a colour-changing writing ink can be obtained without any additive, making it an ideal candidate for 4D printing. This strategy provides a simple and efficient method for preparing pH-tolerant HIPPEs in a one-step process, expanding the range of applications in 4D printing and functional materials. [ABSTRACT FROM AUTHOR]

We fabricated a sensing layer from ink-printed WS 2 flakes and utilized it for UV-activated gas sensing. The optical imaging of the structure made by repeated printing revealed the continuous layer comprising sub-µm flakes, confirmed independently by small-area AFM images (1×1 µm2). The activity of the sensing surface was investigated locally via AFM scanning of the surface with a polarized probing tip. The results indicated that the applied UV light amplifies the existing conducting paths in the dark. These hot spots are associated with the sensing activity of the WS 2 surface (local adsorption-desorption centers). Gas sensing experiments revealed that the DC resistance of the WS 2 sensor changes in the opposite direction for increasing concentrations of NO 2 and NH 3, which correlates with the electron-accepting and electron-donating properties of these species. On the contrary, low-frequency noise intensifies gradually in both gases, and relative changes in noise responses are higher than DC resistance responses for all investigated concentrations. The lowest detection limit obtained was 103 ppb from DC responses for NO 2 and 168 ppb from noise responses for NH 3. The studies of sensing responses for mixtures of the mentioned target gases revealed that the amplitude of resistance fluctuations is not a direct summation of spectra obtained for pure compounds. Such an effect observed for mixed gases indicates that the intermittent reactions between both species before adsorbing at the sensing surface or in the adsorption centers impact their detection. [Display omitted] • UV light activates hot spots in the ink-printed WS 2 enhancing sensing responses. • The lowest detection limit obtained was 103 ppb for NO 2 and 168 ppb for NH 3. • NO 2 and NH 3 produce opposite DC responses in correlation with redox properties. • Low-frequency noise increases gradually for increasing concentration of both gases. • Concentration of NO 2 and NH 3 can be determined from gas mixtures by SVM algorithm. [ABSTRACT FROM AUTHOR]

• The disposable screen-printed electrodes were designed to detect DCP, enabling rapid assessment of this biomarker. • This experiment uses screen ink printing electrode, which can effectively control the contact area of the electrode. • Flower-like gold nanoparticles were produced on the surface of ITO electrode by electrodeposition. A multi-signal amplification system using an ITO electrode printed with disposable screen ink was developed for the rapid detecting des-gamma-carboxy prothrombin (DCP). Gold nanoparticles, uniformly shaped, were electrodeposited on the ITO electrode to improve conductivity and biocompatibility. To boost the sensor's sensitivity, isoreticular metal–organic framework-3 (IROMF-3) and methylene blue (MB) were employed to expand the electrode's surface area and intensify the current signal. Additionally, the avidin-loaded silver nanoelectrode, capable of binding more biotinylated DCP antibodies, further heightened sensitivity. The developed immunosensor effectively detected trace DCP in serum, with a linear range of 0.31 ng/mL to 40 ng/mL, a detection limit of 0.138 ng/mL, and a recovery rate of 97.9–109.2 % under optimal experimental conditions. This study offers a promising approach for the rapid field detection of trace DCP in serum. [ABSTRACT FROM AUTHOR]

• The water-in-oil Pickering PDMS emulsion is for the first time successfully used as printing ink to fabricate multi-walled carbon nanotube (MWCNT) / silicone rubber foams through direct ink writing three-dimensional printing. Moreover, the yield stress of the emulsion is the highest compared with that of the reported printing inks with microscale porogens. • The highest resolution was achieved with printed filament diameter of 229±19 μm. • The prepared composite foam demonstrated excellent stretchability, ultralow compression modulus and hyper compressibility/cycling endurance. • The prepared composite foam exhibited excellent piezoresistive performance including rapid response time, high linear sensitivity (3.32 KPa-1) over a broad working range (27 - 900 KPa) and prominent long-term durability. Conductive nanomaterial/silicone composite foam with stable electrical conductivity, high porosity and ultra elasticity is an ideal flexible material in sensor field. High porosity of composite foams has been achieved through direct ink writing (DIW) three-dimensional (3D) printing. However, low thixotropic properties of printed inks hinder the realization of complex, high-resolution 3D porous structures. On the other hand, the distribution of nanofillers in composite foams make it hard to simultaneously obtain stable electrical conductivity and outstanding elasticity. Herein, ultra-elastic multi-walled carbon nanotube (MWCNT) / silicone rubber foams with stable electrical conductivity and high hierarchical porosity were fabricated through DIW 3D printing. Complex shaped and high-resolution 3D printed porous scaffold structures were achieved through a high-performance printing ink which was a water-in-oil Pickering emulsion fabricated from the emulsification of MWCNT aqueous dispersion in a silicone precursor through a solid emulsifier amphiphilic SiO 2 nanoparticles. Combining highly hierarchical porosity with unique distribution of MWCNTs, the 3D-architectured MWCNT/silicone rubber foams exhibit excellent stretchability (156 % strain), ultra-low compression modulus of 0.73 KPa and outstanding compressibility/cycling endurance (near-zero stress/strain loss under 1000 compression cycles). Excellent piezoresistive performance, including rapid response time (180 ms) and high linear sensitivity (3.32 KPa−1) over a broad working range (27-900KP), is demonstrated for such foams, together with prominent durability (18000 compression cycles at 200 KPa). A wearable piezoresistive sensor assembled from the as-prepared MWCNT/silicone rubber foam could capture various movements from wrist bending to small deformation resulted from human pulse. [ABSTRACT FROM AUTHOR]

[Display omitted] • The anti-counterfeiting SERS tag (Ag@SiO 2) encoding with flexible information was fabricated. • The anti-counterfeiting Ag@SiO 2 shown high security, excellent stability and anti-interference property. • The Ag@SiO 2 was successfully printing on surface of paper through security ink and shown excellent anti-counterfeiting effect. The core–shell structured Ag@SiO 2 nanomaterial integrated with surface-enhanced Raman scattering (SERS) spectroscopy promises a critical application in anti-counterfeiting. Security labels have been fabricated based on Ag@SiO 2 embedded with Raman reporters. The Ag@SiO 2 nanomaterial shows good stability and excellent anti-interference property for anti-counterfeiting. Multiple kinds of Raman probe molecules have been anchored in the Ag@SiO 2 labels to provide specific and abundant encoding information. The flexible encoding security information could be controlled conveniently by adjusting probe molecules, which not only enrich the SERS information but also improve the level of anti-counterfeiting. Furthermore, the Ag@SiO 2 shown excellent stability in organic solvent, and successfully used in ink for the anti-counterfeiting application. [ABSTRACT FROM AUTHOR]

For a specified ink formulation and a printer equipped with a particular light source, an optimal curing depth exists, which can be empirically determined. This depth is critical for maintaining shape fidelity of the printed object. In multilayered prints, each successive layer undergoes multiple exposures, collectively referred to as the cumulative exposure time. Consequently, when fabricating components of varying thicknesses, precise adjustment of exposure time is required to ensure that each layer fulfils the optimum cumulative exposure time criterion This can be achieved by increasing the exposure period for layers with thicknesses below the curing depth or by altering the printing orientation (to increase the number of the sliced layers, if applicable). [Display omitted] 3D printing, also known as additive manufacturing, continues to reshape manufacturing paradigms in healthcare by providing customized on-demand object fabrication. However, stereolithography-based 3D printers encounter a conflict between optimizing printing parameters, requiring more time, and print efficiency, requiring less time. Moreover, commonly used metrics to assess shape fidelity of 3D printed hydrogel materials like 'circularity' and 'printability' are limited by the soft nature of hydrogels, that can cause irregularities in their boundary. To unlock the full potential of 3D printing of biomaterials, it is also necessary to understand correlation between printing parameters and ink properties. In this work, a method based on curing depth, overcuring (cumulative cure), and print thickness was developed, which enables a time-efficient and reliable determination of printing conditions for complex geometries using gelatin methacrylate hydrogel biomaterial ink. We also examined the impact of printing direction on the print quality in terms of object/print thickness and aspect ratio. Moreover, the effects of dye concentration, exposure time, and layer thickness on print quality were evaluated, with discussions focused on the correlation between print dimension to layer thickness. Further evaluation was achieved by successfully printing bioinspired corneal stroma-like scaffold and delicate structures like a contact lens and a model eyeball, substantially expanding the scope of this method in producing high-quality prints with intricate details. We also demonstrate the effectiveness of 'Feret ratio,' another measure of object shape, in assessing the shape fidelity of different prints. Overall, the results highlight the practical potential of this method in enhancing the speed and reliability of the 3D printing processes involving complex geometries using a low-cost 3D printers. [ABSTRACT FROM AUTHOR]

Traditional planar-thick electrodes cannot significantly enhance the energy density of sodium-ion batteries (SIBs) due to the long and tortuous ion diffusion path within the high-tortuosity electrodes, resulting in low utilization rate of active materials. Constructing three-dimensional structured electrodes (3DSEs) with low-tortuosity has been proven an effective strategy to improve the energy density of SIBs. In this study, the 3DSEs with a linear arrayed structure are designed and fabricated using the direct ink writing (DIW) method. The influences of several key fabrication parameters on the morphology structures and electrochemical performances of 3DSEs are experimentally investigated. Results demonstrate that the 3DSEs present a much higher areal capacity and a superior rate performance than the planar electrodes. The 3DSEs with three printing layers fabricated using a nozzle diameter of 0.4 mm and a printing interval of 1.2 mm deliver a high areal capacity of 1.7 mAh cm−2 at 50 mA g−1 and a long-term cycling performance over 400 cycles at 500 mA g−1. This work provides helpful guidance for making low-tortuosity 3DSEs by optimizing the processing parameters. [ABSTRACT FROM AUTHOR]

[Display omitted] • A pyridine-coumarin based probe senses cyanide ion in water. • The probe showed color change from red to blue fluorescence with turn-on response. • The probe used as a digital printing ink material and showed color change for CN− ion. • The developed probe effectively detects cyanide ion in different water samples. The work designed and described here is for the effective recognition of cyanide ion. A novel core (PC) with coumarin moiety as a signaling unit and pyridinium as an acceptor unit and these moieties linked by π-conjugation. In which CN− ion binds in the pyridine ring via nucleophilic addition and produces changes that are captured by different techniques to prove its sensing efficiency. The probe displays a visual color variation to pale orange from purple and also exhibits blue fluorescence from red fluorescence upon cyanide addition. The probe PC sensing ability towards CN− ion has been confirmed by various spectral measurement. In UV–visible technique, a blue shift was observed by the probe with CN− ion. In fluorescence measurements, a peak appeared at 704 nm, which corresponds to the probe encountering a peak enhancement with the added cyanide ion. The binding stoichiometric ratio among the probe and CN− ion is to be 1:1 in jobs method. The probes detection limit and binding constant were calculated to be 0.39 nM and 7.07x104 M. The probe is used as a single component ink and injected into a cartridge and printed on paper which is used as a tool to detect cyanide in water. Besides, the probe successfully senses cyanide ion in various water samples. [ABSTRACT FROM AUTHOR]

Double perovskites of diyttrium magnesium titanate are synthesized by low-temperature combustion method at 1173 K - 4 h, marking a decrease in thermal budget 625 K - 5 h with conventional practice. From the UV–visible spectra, the bandgap is obtained as 3.653 eV. A series of Dy3+ ions are doped in the crystal lattice giving pure white emission at 353 nm excitation and red emission at 980 nm excitation. The crystal structure is confirmed by FESEM and Raman analysis. The optimal 2 wt% elemental doping is inveterate from the XPS analysis whereas the phosphors remain stable under extreme thermal conditions, realized from the TGA. Further monovalent Li+, divalent Sr2+, or trivalent Sm3+ ions are co-doped in the crystal matrix, which chiefly enhances the crystalline, optical, and luminescence properties for Li+ sensitization. These CIE parameters are amended to ideal white light with coordinates (0.326, 0.333), color temperature of 5819 K, and color purity of 2.5 %, signifying a novel ideal white light emission. Anti-counterfeit inks are prepared using PVA due to the red emission of the phosphor under NIR excitation, distinctive for double wavelength fluorescence printing ink technique to tackle serious counterfeiting. [ABSTRACT FROM AUTHOR]

This work investigated the effect of octenyl succinic anhydride starch (OSA S) on the 3D printing performance of corn starch-based emulsion-filled gels containing egg yolk. The influence of OSA-S concentration on emulsion droplet size, ζ-potential and stability, as well as the printing performance, rheological properties and microstructure of gel were discussed. The results indicated that the addition of OSA-S significantly improved the accuracy of the printed objects, with the best accuracy of the models printed using OSA-1.6 and OSA-2.0 inks. Emulsion tests showed that increasing the OSA-S content reduced the droplet size, increased its ζ-potential, and enhanced the stability of the emulsion. Rheological analyses showed that the energy storage modulus, loss modulus, and apparent viscosity of the gels were slightly enhanced with increasing OSA-S content. Microstructural analysis showed that OSA-S increased the density of the gel microstructural network. In addition, the addition of OSA-S enhanced the thermal stability of the gels and facilitated the transition of water molecule states from free water to bound water. The melting temperature of the gel gradually increased from 135.72 °C to 147.52 °C with the increase of OSA content. This study aims to develop promising 3D printing ink to facilitate its industrial applications. • Developed a starch-based emulsion-filled gel system stabilized with octenyl succinic anhydride starch (OSA S) for 3D printing • OSA-S improved storage stability of emulsion. • OSA-S slightly enhanced the mechanical strength and viscosity of the gel. • OSA-S densified the microscopic network structure of gel. • OSA-S improved 3D printing accuracy of starch-based emulsion-filled gel. [ABSTRACT FROM AUTHOR]

There is a great demand for dysphagia diets as the number of old dysphagic patients is increasing rapidly with the aging population trend. This study is aimed to develop attractive dysphagia diets using 3D printing based on succinylated lactoferrin-luteolin nanocomplexation incorporated with combinations of low acyl gellan gum (LAG), high acyl gellan gum (HAG) and gelatin (GL). Rheological, textural, and gel strength of tested inks were examined to assess the potential of the inks for dysphagic diets. The combination of 0.2 g/100 g HAG, 2 g/100 g LAG, and 2 g/100 g GL displayed the optimal printing quality, self-supporting ability, and stability. Concomitantly, it had exceptional water holding capacity and water content. The feasibility of inks as dysphagia diets was evaluated using IDDSI tests, which showed HAG\LAG\GL can be classified as level 4-puree/extremely thick foods and was specifically designed for dysphagic individuals. Radical scavenging assays and in vitro digestion simulations demonstrated the HAG\LAG\GL possessed substantial antioxidant capabilities and maximally enhanced the bioaccessibility of luteolin. Correlation analysis showed quite significant difference between the control and HAG\LAG\GL. These findings underscore the importance of precise colloidal content and types in ensuring optimal printability in 3D printing applications, and provide insights on the development of attractive 3D printing dysphagia diets. • Lactoferrin-luteolin nanocomplexation were creatively loaded into 3D printing inks. • Nanocomplexation-based HAG\LAG\GL ink is appropriate for dysphagic individuals. • Succinylated nanocomplexation-based inks presented excellent antioxidant capacity. • IDDSI confirmed printing ink is classified as level 4-puree/extremely thick foods. • Newly designed 3D printing ink have tremendous potential in dysphagia diets. [ABSTRACT FROM AUTHOR]

The emerging of flexible package market compels us to develop printing inks that are eco-savvy and suitable for polymer films. Owing to the advantages of low toxicity, environmental-friendly and cost-effective, water-based inks growingly occur to researchers and the studies on binders for water-based inks unprecedentedly flourish. Notwithstanding, the adhesion on polymer films and the slower dryness rate constrain the water-based inks to be the mainstream in the field of flexible package printing. In this work, a crosslinkable polyacrylate emulsion for water-based inks binders was successfully synthesized via semi-continuous seed emulsion polymerization to improve the adhesion and dryness rate of ink films. Particularly, crosslinkable monomer allyl acetoacetate (AAA) was utilized as crosslinkable monomers, hexamethylenediamine (HDA) was added as a crosslinker. Isobornyl methacrylate (IBOMA) was employed to endow the emulsion with desirable adhesion for water-based inks. The viscosity, surface tension, water contact angle, particle size distribution and glass-transition temperature (Tg) were evaluated to research the influence of the AAA and HDA crosslinkable system. Performances of the acrylate emulsion and the latex films, with emphasis on resistance to Ca2+ and thermal stability were obviously superior to other polyacrylate emulsions synthesized in this paper. The 100 % adhesion ratio on polyvinyl chloride (PVC) and polyethylene (PE) films and 80.08 % adhesion ratio on biaxially oriented polypropylene (BOPP) was attained with AAA-HDA crosslinkable polyacrylate emulsion. The dryness rate was accelerated from 23 mm/30 s to 40 mm/30 s. This work provides ideas and inspiration for design of the water-based inks that served in flexible package. • Synthesis of self-crosslinkable polyacrylate latex binder with allyl acetoacetate-hexamethylenediamineresin • Preparation of red water-based inks with AAA-HDA self-crosslinkable polyacrylate emulsion as binders • Calculating the adhesion ratio of the latexes on PE, PVC and BOPP films • Evaluating the dryness rate of prepared water-based inks [ABSTRACT FROM AUTHOR]

With the increasing prevalence of swallowing difficulties among the elderly, 3D printing technology has emerged as a promising approach to create attractive and appetitive dysphagia diets. This study focused on synthesizing bigels composed of beeswax oleogel (OG) and gellan gum hydrogel (HG) to explore their potential for 3D printing dysphagia diets. The ratio of OG to HG plays a pivotal role in determining the gel network structure, rheological properties, and water distribution of the bigels, thereby influencing their suitability as 3D printing ink. Notably, a bicontinuous structure achieved with an OG to HG ratio of 1:1 (sample 1-1) imparted desirable properties for 3D printing, including moderate shear-thinning behavior, ensuring smooth extrusion, excellent thixotropy for maintaining structural integrity, and adequate storage modulus for self-supporting during printing. These were indicated by lower flow index (n value) of 0.18, longer time respond to the applied stress (λ value) of 9.51 ± 0.32 s, higher creep recovery rate of 55.51 ± 1.36%, thixotropic recovery rate up to 93.23 ± 0.72%, and uniform moisture distribution across semi-bound water and free water with ratio of 56.94 to 43.06, compared to bigels with OG-in-HG and HG-in-OG structures. Evaluation of the 3D printed bigels through the International Dysphagia Diet Standardization Initiative (IDDSI) confirmed that sample 1-1 (classified as Level 5-Minced and Moist) was suitable for individuals with swallowing difficulties. This study provides new insights into developing visually appealing dysphagia diet using 3D printing. [Display omitted] • 3D-printed bigels are emerging as a promising application for dysphagia diets. • Micro/macro-properties of bigel can be modulated by adjusting oleogel-hydrogel ratio. • 3D printing and swallowing properties are closely related to rheology of bigels. • Bigel with oleogel-hydrogel ratio of 1:1 is optimal for printing and swallowing. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO) is a derivative of graphene, which has been widely used as the conductive pigment of many water-based inks and is recognized as one of the most promising graphene-based materials for large-scale and low-cost production processes. In this work, we evaluate a custom functionalised reduced graphene oxide ink (f–rGO) via inkjet-printing technology. Test line structures were designed and fabricated by the inkjet printing process using the f–rGO ink on a pretreated polyimide substrate. For the electrical characterisation of these devices, two-point (2P) and four-point (4P) probe measurements were implemented. The results showed a major effect of the number of printed passes on the resulting resistance for all ink concentrations in both 2P and 4P cases. Interesting results can be extracted by comparing the obtained multipass resistance values that results to similar effective concentration with less passes. These measurements can provide the ground to grasp the variation in resistance values due to the different ink concentrations, and printing passes and can provide a useful guide in achieving specific resistance values with adequate precision. Accompanying topography measurements have been conducted with white-light interferometry. Furthermore, thermal characterisation was carried out to evaluate the operation of the devices as temperature sensors and heaters. It has been found that ink concentration and printing passes directly influence the performance of both the temperature sensors and heaters. [ABSTRACT FROM AUTHOR]

The robocasting technique has shown great potential due to its versatility, allowing the fabrication of custom-shaped, dense or porous structures, through layer-by-layer deposition. The technical feasibility of robocasting depends on rigorous control of the rheological properties of printing inks, which needs to have fluidity for pumping and plasticity for extrusion/printing, while being able to withstand the weight of overlapping layers. The aim of this work is to produce cellular glass structures by direct printing (robocasting) using bentonite to overcome the lack of plasticity of glass powders. Ceramic inks containing recycled glass powders (d 50 < 4 μm) and bentonite (6.5–9.5 wt%) were blended and printed using a 1.60 mm printing nozzle at a printing speed of 10 mm/s. The three-dimensional structures were dried at room temperature for 24 h and then fired at 700 °C for 1 h at a heating rate of 10 °C/min. The components obtained from recycled glass showed porosities of up to 53%, pore sizes between 1090 and 1870 μm and compressive strength of ∼18 MPa. [ABSTRACT FROM AUTHOR]

The printing ink on the plastic surface greatly reduces the quality of recycled plastic products. In this work, quaternary ammonium-modified waste cooking oil (WCOQE) was fabricated, using waste cooking oil, epichlorohydrin and trimethylamine aqueous solution as raw materials, by ring-opening esterification and quaternary amination reaction. The synthesis conditions of WCOQE were optimized, and the structure and properties of WCOQE were characterized by FTIR, zeta potential and 1H NMR. Furthermore, WCOQE had excellent emulsifying performance, low kraft point, low CMC value, good foaming and stability, which could effectively reduce the surface tension of water, showing application potential in the field of plastic deinking. Importantly, compared with the waste cooking oil without deinking effect, the WCOQE had an excellent deinking performance on the ink on plastic surface, and the deinking efficiency could be improved by increasing the concentration of deinking agent, the deinking temperature, and prolonging the pre-soaking and stirring time. The results of AFM, EDS, optical photos and Leica microscope showed that the roughness changed significantly, and the ink molecules were gradually peeling off. This work highlighted the excellent potential of quaternary ammonium-modified waste cooking oil for the removal of printing inks on the plastic surface. [ABSTRACT FROM AUTHOR]