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3D printing allows for the cost-effective fabrication of moulds and can cast complex shapes. In this study, alumina cement and fine aggregates for refractories were used as the main raw materials, and saturation was adjusted to an appropriate level to control the cement binder mixture for sand casting. For cast iron, the mould must withstand temperatures of up to 1400 °C and must exhibit sufficient strength, gas permeability, and thermochemical durability at high temperatures. To accomplish these requirements, 3D printing powder was prepared by adjusting the ratio of fine aggregate (D50: 30 μm) and an even finer cement component (D50: 4 μm). To improve the moulding quality, a green body was used to optimise the cement admixtures to increase the strength, and the saturation level of the 3D printer was adjusted for dimensional accuracy. The high-temperature durability of the mould was evaluated by measuring its strength after heat treatment, using Simultaneous Thermal Analysis (TG-DSC), and through dimensional stability assessment. In addition, the pores of the specimens were analysed through microscale X-ray tomography. The surface resolution and tolerance of the final casting were determined by a 3D image roughness test using a surface roughness scanner. The cement exhibited the shortest curing time and the highest strength when the mass ratio of CA (CaO·Al2O3) to C12A7 (12CaO·7Al2O3) was 8:2. The final mixing mass ratio of cement to the fine aggregate was 8:2, which was determined based on the relationship between flowability and powder bed surface quality. The results proved the high-temperature thermal stability of the 3D-printed mould, which showed a total mass reduction of less than 3% and a low coefficient of linear expansion up to 1300 °C. Consequently, the suitability of the 3D-printed moulded body, composed of casting sand with cement as a binder, for casting at temperatures >1400 °C was demonstrated. Additionally, the final printed porous mould de-powdered easily, and its recyclability was verified by strength testing various mass ratios of fresh and recycled powder. Therefore, through optimisation of the material combinations and adjustment of the 3D printing process parameters, optimal gas permeability and moulding resolution could be achieved without any casting defect, while maintaining handling strength. The findings of this study demonstrate the potential of expanding the scope of powder-bed-based 3D printing of cement material to the casting market.

Attention has recently been paid to ink-jet printing inks to more environmentally friendly types and faster methods with lower energy consumption. The ink-jet printing industry has a preference to use ultraviolet-curable inks for packaging and labeling applications. This research reports a simple approach to prepare a water-based UV-curable ink-jet ink based on urethane acrylate to print onto the transparent flexible polyethylene terephthalate substrate. Isophorone diisocyanate, dimethylolpropionic acid, a low molecular weight polyester resin, and 2-hydroxyethyl methacrylate used to synthesize the urethane acrylate resin. Then, the prepared resin was neutralized with triethylamine and emulsified in deionized water. Fourier transformed infrared spectroscopy spectra characterized the chemical structure of synthesized resin. The gel permeation chromatography was used to determine the synthesized resin's molecular weight. The hydroxyl value, acid value, conversion percentage under UV radiation, transparency, haze, and surface tension results of the emulsified resin were measured. The physical properties of prepared ink-jet ink, such as rheology, surface tension, and dynamic light scattering, were measured. The ink-jet ink could fabricate uniform patterns by a general ink-jet printer onto the transparent polyethylene terephthalate flexible substrate. Eventually, the acceptable appearance was achieved due to the transparency and clarity of the printed polyethylene terephthalate. [ABSTRACT FROM AUTHOR]

Metal halide perovskites have raised huge excitement in the field of emerging photovoltaic technologies. The possibility of fabricating perovskite solar cells (PSCs) on lightweight, flexible substrates, with facile processing methods, provides very attractive commercial possibilities. Nevertheless, efficiency values for flexible devices reported in the literature typically fall short in comparison to rigid, glass‐based architectures. Here, a solution‐processable fullerene derivative, [6,6]‐phenyl‐C61 butyric acid n‐hexyl ester (PCBC6), is reported as a highly efficient alternative to the commonly used n‐type materials in perovskite solar cells. The cells with the PCBC6 layer deliver a power conversion efficiency of 18.4%, fabricated on a polymer foil, with an active area of 1 cm2. Compared to the phenyl‐C61‐butyric acid methyl ester benchmark, significantly enhanced photovoltaic performance is obtained, which is primarily attributed to the improved layer morphology. It results in a better charge extraction and reduced nonradiative recombination at the perovskite/electron transporting material interface. Solution‐processed PCBC6 films are uniform, smooth and displayed conformal capping of perovskite layer. Additionally, a scalable processing of PCBC6 layers is demonstrated with an ink‐jet printing technique, producing flexible PSCs with efficiencies exceeding 17%, which highlights the prospects of using this material in an industrial process. [ABSTRACT FROM AUTHOR]

The dispersion of low surface polarity ultra-fine powders has been a technical bottle-neck in many industrial applications, including ceramic or glass decoration and solar electrodes. Herein, we report a surface modification method to improve the adsorption strength between the ultra-fine (300 nm) powder and dispersant by coating a layer of mesoporous silica on the surface of a glass frit. The modified ultra-fine glass frit shows a high density of polar surface functional groups which can increase the adsorption amount and strength between the modified powder and the dispersant, as confirmed by the adsorption experiment and IR analysis. The modified powder also was used to prepare ceramic ink which can be completely filtered under a 1 μm sized pores filter, thus satisfying the requirement of industrial ink-jet printing. [ABSTRACT FROM AUTHOR]

The Department of Defense (DOD) and first responder communities are evaluating and developing optical systems for the detection and identification of explosives and components used for assembling homemade explosives (HMEs). Emerging detection technologies must be evaluated with authentic hazard material concentrations to ensure their accurate and reliable use in the field. In this work, infrared (IR) reflectance spectra over the spectral rage of 1000-1700 cm-1 were collected for different concentrations of inkjet-printed RDX (cyclotrimethylenetrinitramine) samples deposited onto aluminum substrates. A plot of the integrated area of both the symmetric and asymmetric NO2 vibrational bands for RDX on aluminum exhibited good linearity over the concentration range 20-500 µg/cm². Detection limits for RDX on an aluminum surface were calculated to be 10.7 µg/cm² for the symmetric NO2 vibrational band and 1.4 µg/cm² for the asymmetric NO2 vibrational band. Evaluation of the NO2 vibrational band areas at different locations of the RDX array demonstrated that the samples exhibited good homogeneity across the surface. The concentration of an unknown sample of RDX on aluminum was determined using the fitted equations; results showed good agreement between the calculated and actual RDX surface concentration. The lot-to-lot variation of RDX on the aluminum surface was compared using the long wavelength infrared (LWIR) spectral band areas for two different lots of standards printed at the same RDX surface concentration. Results showed excellent lot-to-lot agreement indicating good reproducibility of the standards for RDX. [ABSTRACT FROM AUTHOR]

Bioresorbable polymer microparticles are widely used to provide long-lasting drug delivery in several chronic diseases. Having fine control over the physical properties of such microparticles can improve product reproducibility, performance and process efficiency. By using an ink-jet based droplet generator device, a new approach to microparticle manufacture was explored that uses an extremely rapid phase-separation to produce highly uniform, injectable microparticles from PLGA and a PLA/PLGA blend. To demonstrate the possible pharmaceutical applicability of the microparticle printing technique, the approved peptides ciclosporin A and octreotide were formulated, producing low-density microparticles that showed between sustained release over several months. The facile scale-up of the technique was demonstrated by using an array of 256 ink-jet nozzles, allowing over 1 million discrete particles per second to be produced. The new apparatus and methods described herein could be used across a wide range of biomaterials and therapeutic compounds. [ABSTRACT FROM AUTHOR]

The development of new technologies in electronics related to flexible polymeric substrates forces the industry to introduce suitable tools (special type of dispensers) and modern conductive materials for printing electronic circuits. Moreover, due to the wide use of inexpensive polymeric foils (polyethene, PE, or poly(ethylene terephthalate), PET), there is a need to develop materials with the lowest possible processing temperatures. The present paper presents the selection criteria of suitable components and their preparation for obtaining electrically conductive ink with a special nanosilver base. In the case of the discussed solution, all components allow to make circuits in relatively low sintering temperature (even below 130°C). Additionally, the authors show the most significant ink parameters that should be taken into consideration during Research and Development (R&D) works with electrically conductive inks. Moreover, ink stability parameters are discussed and some examples of printed circuits are presented. [ABSTRACT FROM AUTHOR]

A novel outline of a planar photoelectrochemical cell consisting of a semiconductor layer topped by subsequent layers of a digitated insulator and counter electrode is introduced. The use of vertically separated electrodes represents a major development in reducing the footprint (inactive areas) of planar electrochemical cells. The cells, consisting of a nanoparticular titania photoanode and a digitated, metallic cathode, were fabricated by a strictly additive process employing material printing as the exclusive deposition and patterning tool. Transparent conductive oxide-coated glass and polyethyleneterepthalate sheets were used as substrates; nanocrystalline titania dispersion bonded by a novel organosilica binder was used for the fabrication of the photoanode and gold or carbon inks for the fabrication of the digitated cathodes. Due to the digitated shaping of the cathode, photoelectrochemical response was not suffering from iR drop down to low electrolyte ionic strengths. The printed cells were used for electroassisted photocatalytic degradation experiments with aqueous solutions of coumarin. Considerable acceleration of the coumarin degradation rate compared to the plain photocatalytic mode was observed. [ABSTRACT FROM AUTHOR]

An eddy current sensor with an ink-jet printed flexible inductor has been designed and fabricated. The inductor has been designed by means of software developed in-house. It has been fabricated by ink-jet printing with silver ink on a flexible substrate. The inductor is a part of the oscillator circuit whose oscillating frequency is measured by a microcontroller. The sensor characteristics have been analyzed for two types of application. The first considered application is the displacement of a large conductive target in a direction perpendicular to the inductor plane. The second considered application is the displacement of a small steel ball parallel to the inductor plane. Inductance and oscillating frequency have been measured in order to completely characterize the sensor. The obtained results validate the use of the sensor for both considered applications, and are in good agreement with the simulations. The advantages of this type of sensor are low cost, the possibility for the inductor to match any curved surface and flexibility and precision of the inductor design.

High‐performance, ink‐jet printable OLED materials have been successfully developed. Our wide libraries of platforms and small molecule hosts were effective for improving efficiency and lifetime of OLEDs. For wide color gamut, new emitters with deep in color and narrow full‐width at half maximum were developed. Further, solvent systems having physical properties suitable for improving film uniformity in pixels were found. [ABSTRACT FROM AUTHOR]

Printing systems operate in general as a system of color its color scale is limited as compared with the system color satellite images. Satellite image is building from very small cell named pixel, which represents the picture element and the unity of color when the image is displayed on the screen, this unit becomes lesser in size and called screen point. This unit posseses different size and shape from the method of printing to another, depending on the output resolution, tools and materials of each system scribal. Lithography using ink pasta, the laser uses a powder color. Ink-jet uses liquid inks water and photography based on the optically sensitive colors. All of these factors and substances affect the quality of the printed image. In this paper different printing systems were used to print an image of SPOT-4 satellite, caver part of Sharm Elshekh area, Sinai, Egypt, on the same type of paper as much as possible, especially in the photography. This step is followed by measuring the experimental data, and analyzed colors to determine the best printing systems for satellite image printing data. The laser system is the more printing system where produce a wider range of color and highest densities of ink and access much color detail. Followed by the offset system which it recorded the best dot gain. Moreover, the study shows that it can use the advantages of each method according to the satellite image color and quantity to be produced.

Roll-to-roll (R2R) solution processing of thin film devices offers savings to cost, time, and material waste. Emerging technologies in electronics, optoelectronics, and microfluidics could potentially benefit from these manufacturing advantages. However, the associated complex pattern requirements are difficult to attain with traditional solution-based methods, barring significant concessions to device performance and process scalability. In this paper, we present and implement a novel hybridization of continuous ( e.g ., slot die) and on-demand ( e.g ., inkjet) techniques designed to address these shortcomings, wherein outflow from localized regions of an extrusion die is actuated in real time to produce patterns. Pattern features were produced with aqueous solutions of poly(vinyl alcohol) (PVA), and poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), and deposition phenomena were observed in situ using a specialized roll feed imaging system. Minimum feature size is shown to be directionally dependent, with transient flow effects dominating along the axis coincident with substrate motion, and sensitive to several process inputs as well as coating material properties. Strategies for managing residual fluid in the die cavity and beneath the die lip are illustrated, through flow actuation mechanisms and exploitation of deposition phenomena, to optimize pattern fidelity. [ABSTRACT FROM AUTHOR]

The paper reports a capacitive sensor for measuring liquid level which was fully fabricated with the inkjet printing technology. The liquid level measurement based on capacitive sensing is already well known technique. The novelty of presented capacitive sensor is used technology, obtained structure flexibility and its dimension. The sensor structure was printed on a thin Kapton substrate with dimensions of 210 mm x 12 mm, and the thickness approximately 27 μm. The sensor was tested on a vessel witch was filled and emptied with water. The tests shown sensor linearity in liquid level sensing and the lack of hysteresis. Obtained sensitivity of the prototype sensor was approximately 74·10 -3 pF/mm. The sensor structure can be applied to any shape of vessel. Furthermore, its construction is very simple and in mass production costs could be extremely low. This type of sensor was designed especially for autonomous cleaning and washing machines for large areas. [ABSTRACT FROM AUTHOR]

The ink-jet printing has been widely applied in the decoration of ceramic tiles in last ten years since its excited characteristics provide the possibility to produce the customized ceramic tiles with higher image definition at a lower cost in a shorter duration. The number of ink-jet printers in operation worldwide increased rapidly in recent years. Besides the printer, one of the critical factors for an effective printing is inks. This paper focuses on the ceramic ink and reviews recent development on the preparation of ceramic inks by various methods, such as sol–gel, reverse microemulsion, polyol, hydrothermal and mechanical grinding. Some aspects for future development are proposed based on the application of ceramic inks in industries. [ABSTRACT FROM AUTHOR]

In this study, the cotton fabrics were modified with different polyamidoamine (PAMAM) dendrimer concentrations to yield antimicrobial and efficient polymeric materials for ink-jet printing. PAMAM dendrimer has been covalently grafted on cotton fabric via the reaction of cellulosate anion with the cynuric chloride. The obtained modified cotton fabrics were characterized by FTIR and TGA. The morphology and yellowness of modified cotton fabrics were analysed by SEM and UV spectroscopy. The ink-jet printing onto modified cotton fabrics were evaluated at different pHs. The results at optimum pH indicated that by increasing the PAMAM dendrimer concentration in modified cotton fabric not only the colour strength of reactive ink-jet printed fabric increased but also the antimicrobial cotton fabric produced. A comparision between printing modified and unmodified cottons suggest that the PAMAM dendrimer has the potential for using in single-phase ink-jet printing. The yielded prints demonstrate excellent colour fastness for washing and dry/wet crocking properties. [ABSTRACT FROM AUTHOR]

We report the performance of inkjet printed red, green and blue OLEDs, with focus on transition from evaporated blue common layer to printed blue panel design. Printed OLED device efficiencies and colors are reported, and we demonstrate that in these metrics, printed red, green and blue OLEDs are now comparable to state-of-the-art vapor-processed devices. [ABSTRACT FROM AUTHOR]

Highlights: [•] Clear evidence that temperature could be used to manipulate the wetting properties. [•] Usability studies of organic solar cell materials never investigated previously. [•] Implementation of ZnO nanorod layers, which are a very promising materials for various applications. [•] Proof those elevated temperatures permanently reverse the effects of plasma treatment. [Copyright &y& Elsevier]

A new set of different ink-jet inks to be apply as a 3D object and extrafine layers to protect the decoration made by ink-jet technology. These new inks are obtained through the development of new frits based on monophasic crystal vitro structures that allows ceramic effects obtained via digital decoration. The new inks improve the ability of application by ink-jet heads in order to achieve aesthetics and decorative effects than those obtained with conventional decoration.Se han desarrollado un conjunto de diferentes tintas ink-jet, para aplicar como objeto 3D y capas extrafinas con el fin de proteger la decoración realizada mediante tecnología ink-jet. Estas nuevas tintas se obtienen a través del desarrollo de nuevas fritas basadas en estructuras vitro cristalinas monofásicas que permiten obtener efectos cerámicos mediante decoración digital. Las nuevas tintas mejoran la capacidad de aplicación mediante cabezales ink-jet con el fin de conseguir efectos estéticos y decorativos superiores a los obtenidos con la decoración convencional.

Abstract: Cellulose linen fabric samples subjected to cationization using different cationizing agents: dodecyl trimethyl ammonium bromide (DTAB), tetra methyl ammonium hydroxide (TMAH), and Quat-188, via pad batch technique, followed by ink jet printing with reactive dyes. The %N as well as the K/S of the cationized samples was found to be depends on: (a) the nature of the cationizing agent and (b) on the time of batching. As the latter increases both of the nitrogen content and K/S increases to a maximum depending on the nature of the reagent used. Further increase in the batching time up to 30h is accompanied by a decrease in both the %N and K/S irrespective of the nature of the cationizing agent used. Cationization improves the printability of reactive dye ink jet printed linen fabrics with no remarkable effect on the overall color fastness properties. [Copyright &y& Elsevier]

UV-curable inks based on a poly(ethylene glycol) diacrylate (PEGDA) matrix and containing a dispersion of aqueous Ag nanoparticles in different amounts from 10 to 50% are prepared for the fabrication of inkjet printed resistors. The composition is adapted to the inkjet requirements in terms of viscosity, surface tension, and particle size. The gel content, glass transition temperature, conversion, UV-Vis absorption, morphology, and DC electrical properties of the materials are characterized. It is found that the NPs dispersed in the polymeric matrix realize a percolating path by aligning themselves in chains, which results in a reduction of the percolation threshold. Thus, resistivity is well beyond the dissipative range. [ABSTRACT FROM AUTHOR]

Copyright of Technical Journal / Tehnički Glasnik is the property of Polytechnic of Varazdin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An eddy current sensor with an ink-jet printed flexible inductor has been designed and fabricated. The inductor has been designed by means of software developed in-house. It has been fabricated by ink-jet printing with silver ink on a flexible substrate. The inductor is a part of the oscillator circuit whose oscillating frequency is measured by a microcontroller. The sensor characteristics have been analyzed for two types of application. The first considered application is the displacement of a large conductive target in a direction perpendicular to the inductor plane. The second considered application is the displacement of a small steel ball parallel to the inductor plane. Inductance and oscillating frequency have been measured in order to completely characterize the sensor. The obtained results validate the use of the sensor for both considered applications, and are in good agreement with the simulations. The advantages of this type of sensor are low cost, the possibility for the inductor to match any curved surface and flexibility and precision of the inductor design. [ABSTRACT FROM AUTHOR]

Abstract: In this work, we propose a piezoelectric droplet generator for injection of well-defined amounts of sample in capillary electrophoresis. We demonstrate stable, precise and drop-on-demand droplet formation for various solutions, with precise control of waveform driving piezoelectric crystal inside the ink-jet head. By tuning the waveform, we can also manipulate the droplet size and delivery frequency. This injector was used in sampling for capillary electrophoresis. As a state-of-the-art application, the analysis of theobromine, caffeine and theophiline using micellar electrokinetic chromatography was developed. The volume of sample (single droplet) analyzed in this experiment was 179pL (RSD=1.2%, n=10). The detection limits for caffeine, theobromine, and theophiline are 0.02, 0.08 and 0.06mML−1, respectively. Compared with conventional methods, the combination of picoliter droplet dispenser with capillary electrophoresis allows precise and accurate sampling, as well as for reduced sample consumption, which will prove to be an efficient tool in quantitative separation and analysis. [Copyright &y& Elsevier]

Abstract: A gas sensor formed by a Platinum (Pt) nanoparticle film and a poly(2-hydroxyethyl methacrylate) (PHEMA) polymer layer is discussed in this paper. The Platinum nanoparticles which have been produced by a modified magnetron sputtering technique are deposited on flexible polyimide substrate. The substrate has been initially patterned with gold interdigitated electrodes (IDEs). A second layer of PHEMA polymer has been delivered on top of the Pt nanoparticles using an ink-jet micro printer. By taking advantage of PHEMA''s known susceptibility in alcohol or humidity vapors, chemical gas sensors of varying sensitivity can be produced by controlling the nanoparticle deposition time. As a result an inexpensive alternative to gas sensors using conventional silicon technology can be realized. [Copyright &y& Elsevier]

Abstract: In this work, an automatic multi-channel ink-jet for chemiluminescence (CL) analysis was developed. The four-channel ink-jet device was controlled by a home-made circuit. Differing from the classic flow injection CL, the whole procedure for CL analysis was automatically completed on a hydrophobic glass side. CL reaction of luminal and hydrogen peroxide for the determination of horseradish peroxidase (HRP) was selected as an application to automatic CL analysis platform. All solutions delivered by different channels were precisely ejected to the same position of the glass slide for the CL analysis. The consumption of reaction solution was reduced to nanoliter level. The whole CL analysis could be completed in less than 4min, which was benefited from the prompt solution mixing in small size of droplet. The CL intensity increased linearly with HRP concentration in the range from 0.01 to 0.5μgmL−1. The limit of detection (LOD) (S/N=3) was 0.005μgmL−1. Finally, the automatic CL system could also be used for the detection of HRP in HRP–protein conjugates, which showed its practical application in immunoassay. [Copyright &y& Elsevier]

Design considerations for ultraviolet-nanoimprint lithography resists were investigated focusing on the major issues of ink-jetting performance, pattern formability, release property, and dry etching resistance. Regarding ink-jetting performance, small droplet ink-jetting of 0.7 pl was successfully demonstrated by adjusting the resist fluid property to the ink-jet coater and controlling the resist volatilization. Regarding pattern formability, a resist pattern was imprinted from a mold pattern of 28 nm in width and 60 nm in depth without pattern dimension change. It was thought that modulus control of the resist was more important than resist shrinkage in achieving excellent pattern formability. As for release property, resist with fluorine monomer and with nonreactive fluorine antisticking agent were compared. The results indicated that resist design has the capability to both reduce separation force and maintain a clear mold surface. The mold release agent decomposed with an increasing number of imprint shots, but the low release-force resist with nonreactive antisticking agent was able to control degradation of the mold release agent and thus improve release property endurance. Regarding etching resistance, it was found that increasing the ring parameter of resist is essential for high etching resistance, and resulted in improved etched pattern features of the substrate. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, three-dimensional ordered microbeads structure (3 DOS) was controllably constructed, and was firstly adopted in the enzyme-linked immunosorbent assay (ELISA) for the detection of IgA. The 3 DOS analytical matrix greatly increased the reaction surface and improved the sensitivity of ELISA microassay. Briefly, the 3 DOS dot microarray for bio-analysis was dispensed by the ink-jet micro-device, and assembled in a close box with controlled relative humility (RH). The influence of supporting substrate material, concentration of microbeads suspension, and RH on the conformation of 3 DOS was also discussed in detail. Then the optimum conditions for the uniform and stable 3 DOS for microassay were achieved, and the uniform and stable 3 DOS microarray for the enzyme-linked immunosorbent assay (ELISA) was built up. Finally, the ELISA microassay on the 3 DOS microarray was done to detect IgA and compared with the classic 96-well plate and blank PDMS surface. The results have shown that 15 times reaction time was shortened due to the decreasing of the mass transferring distance; Almost 10 times sensitivity was obtained owing to the increased reaction surface; the large dynamic range was achieved in the 3 DOS ELISA microarray. [Copyright &y& Elsevier]

Abstract: An ink-jet printing method was proposed to solve several conventional problems of ink jet process. PVK (poly(9-vinylcarbazole)) thin film was synthesized and simultaneousely patterned by the reactive ink-jet process (RIP). Gel permeation chromatography shows a linear relationship between the molecular weight of the PVK and the reaction time. The as-synthesized PVK with a controlled molecular weight was applied to an OLED device. Most of the OLED with the RIP–PVK film performed better compared to the reference OLEDs. The luminance graphs indicated the existence of a proper molecular weight leading to the optimum structural conformity which was matched well to the modified OLED structure, showing a linear relationship with the reaction time in the turn-on threshold. This result implies that one can control the proper molecular weight of a polymer and thus the electrical properties of an OLED device via the RIP method. [Copyright &y& Elsevier]

Ink-jet deposition enables more efficient, economic, scalable manufacturing for a wide variety of materials than other additive techniques. The impact of droplets onto a substrate is critical for accuracy control and optimisation of the droplet deposition process. However, most previous research about droplet impact focused on the spreading radius of the droplet, which does not provide enough information for manufacturing purposes. This paper presents a new measure of droplet shape characterisation so that the droplet deposition process can be optimised to build desired geometries. A dimensional analysis is conducted to reduce the number of parameters of the impact conditions. Then the shape evolution of a wide range of impact conditions is simulated with a validated numerical model. The effects of the dimensionless numbers on the shape evolution are examined and analysed. Successive multiple droplets impact is also investigated. [ABSTRACT FROM PUBLISHER]

Abstract: Printing systems operate in general as a system of color its color scale is limited as compared with the system color satellite images. Satellite image is building from very small cell named pixel, which represents the picture element and the unity of color when the image is displayed on the screen, this unit becomes lesser in size and called screen point. This unit posseses different size and shape from the method of printing to another, depending on the output resolution, tools and materials of each system scribal. Lithography using ink pasta, the laser uses a powder color. Ink-jet uses liquid inks water and photography based on the optically sensitive colors. All of these factors and substances affect the quality of the printed image. In this paper different printing systems were used to print an image of SPOT-4 satellite, caver part of Sharm Elshekh area, Sinai, Egypt, on the same type of paper as much as possible, especially in the photography. This step is followed by measuring the experimental data, and analyzed colors to determine the best printing systems for satellite image printing data. The laser system is the more printing system where produce a wider range of color and highest densities of ink and access much color detail. Followed by the offset system which it recorded the best dot gain. Moreover, the study shows that it can use the advantages of each method according to the satellite image color and quantity to be produced. [Copyright &y& Elsevier]

Abstract: Hyperbranched polyurethane-methacrylates were synthesized and used as oligomers for ink-jet printing of LCD color filters. Pigment-based inks containing these hyperbranched polymers (HBPs) were ink-jet printed and fixed by a UV curing reaction to make color patterns on glass substrates. The HBPs exhibited excellent compatibility with pigments and other UV-curable compositions in inks. Surfactants were added and hyperbranched polymers were changed to adjust the rheology of the inks; this adjustment improved the ink for ink-jet printing, with regard to performance such as straight jetting trajectory, deposition accuracy, and uniform drop size. The UV-cured patterns that incorporated HBPs as ink components exhibited good chemical resistance and high nanoindentation hardness. [Copyright &y& Elsevier]

Abstract: An ink-jet method for fabrication of fine and smooth front side highly conductive silver lines on crystalline Silicon substrate is described. The fabricated conductive silver lines on different substrates are characterized by means optical microscope, optical profilometers, scanning electron microscope (SEM), and electrical measurements. The coffee-ring effect is controlled by increasing the solid loading of the ink from 20W% to 40W% and printing at optimum substrate temperature (90–100°C) and optimum printing parameters. Smooth printed conductive silver lines, with line thickness ranges from 0.8∼0.9μm for single pass, are obtained. When increased substrate temperature, a significant reduction of spreading of ink was observed. And conductive silver lines obtained at optimum substrate temperature (90–100°C), free of periodic wrinkles and line bleeding, are produced. The influence of annealing temperature on line resistance, the morphology and functionality of the printed conductive silver lines is optically and electrically analyzed. To deposit thicker lines multiple passes of ink-jet printing were done on polished single crystalline silicon (sc-Si) and standard alkaline (NaOH) textured n+/p single crystalline silicon (n+/p sc-Si). Moreover, the printed conductive silver lines are characterized optically and electrically. And, promising results in terms of printed line thickness and electrical property are achieved. [Copyright &y& Elsevier]

Abstract: An all-printed photosensor based on polyfluorene derivatives has been developed for high illuminance range detection (>100klux). The active layer is a blend of hole-accepting poly(9,9′-dioctylfluorene-co-bis-N,N′-(4-butylphenyl)-bis-N,N′-phenyl-1,4-phenylenediamine) (PFB) and electron-accepting poly(9,9′-dioctylfluorene-co-benzothiadiazole) (F8BT). A top-absorbing architecture was used with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as the transparent electrode. The surface energy of the PEDOT:PSS ink was modified in order to allow printing directly onto the hydrophobic surface of the PFB:F8BT blend layer, placing the transparent electrode at the top of the light sensor structure. The all-printed photosensor shows a linear response over multiple measurements within the illuminance range of (100–400) klux. [Copyright &y& Elsevier]

Abstract: We report a rapid patterning method for interconnects fabrication combining the ink-jet printing of silver nanoparticles and laser sintering on the ceramic substrate. The optimal parameters of laser irradiation were found. As-fabricated interconnects on ceramic substrate possess a sheet resistance 0.38Ω/sq and have good adhesion to substrate. Also, the pulsed laser annealing of silver particles after drying on polyimide substrate was investigated, and optimal parameters of laser irradiation were found to form peeling-free structures. The conductivity of as-prepared lines reached about 20% of bulk silver. [ABSTRACT FROM AUTHOR]

Abstract: Organic thin film transistors with channel lengths below 20μm have been fabricated on plastic substrates using a combination of rotogravure and ink-jet printing exclusively. Gravure is utilized to deposit thin, smooth, and narrow metal lines ideal for gate electrodes; a poly(4-vinylphenol) dielectric; and a poly(2,5-bis(3-tetradecylthiophene-2-yl)thieno[3,2-b]thiophene) (pBTTT) semiconductor using a heated roll. A novel fluid guiding technique is used to maintain closely spaced ink-jet printed source and drain (S/D) contacts. Together these printing processes yield aggressively scaled yet easily manufacturable TFTs with operating frequencies of 18kHz. [ABSTRACT FROM AUTHOR]

Abstract: A technique for the fabrication of chemiresistive sensors using ink-jet printing is reported. Gold nanoparticles stabilised in water were ink-jet printed on gold interdigitated electrodes patterned on an oxidized silicon wafer. As a first step the influence of substrate functionalization, electrode spacing, and nanoparticle density were investigated by electrical measurements and microscopy imaging. Finally a second layer of PHEMA polymer was printed on top of the gold nanoparticle films. The device was exposed to vapours of humidity and ethanol and the obtained results are presented. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we presented a novel water-based nanoparticle printing ink which can easily be used in producing electric-conductive patterns for the microfabrication and microelectronic devices by commercial printers. The well-dispersed nanoparticle ink was composed of metallic colloids which had a gold core less than 5nm in diameter and were protected by two overlapped layers of polymers, poly(N-vinylpyrrolidone) (PVP) and acrylic resin (AR). The double layer protected gold nanoparticle (AuNP) ink was stable against aggregation for more than 1 year even at gold concentration higher than 20%. Viscosity of as-prepared ink was similar to the commercial inks which could be used in producing continuous and smooth lines 10μm in width and could be printed on various substrates. It has been found that the obtained gold patterns after sintered at 500°C for 3h would convert to electrical conductive ones. The density of metallic particles as well as the conductivity of patterns can be controlled by mediating the number of printing layers and the conditions of sintering process. A 50-layer printed line obtained in our experiment showed apparent conductivity of 8.0×104 Scm−1 which was near to the conductivity value of the bulk gold metal. [Copyright &y& Elsevier]