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The purpose of this paper is to deal with an identification of a novel ink-jet printing sensor fabrication technology for fabricating flexible carbon heaters of macro and micro sizes, carbon interdigitated (IDT) electrodes and silver IDT electrodes. The technology involved in the proposed ink-jet printing method and materials used for the formulation of homemade nano-conductive inks (digital inks) are discussed in detail. The ink-jet printed flexible carbon heaters of different sizes (macro and micro) and carbon IDT electrodes and flexible silver IDT electrodes can be used as the flexible sensing layers in electrochemical gas sensors for sensitive and selective gas sensing applications. The characterization of ink-jet printed carbon heaters on Kapton substrate and its results are discussed. Similarly, the results of formulation of silver nano-conductive ink and printing of silver IDT electrodes on Kapton and its characterization are reported here for the first time.

Flexible carbon heaters of different sizes (macro and micro), carbon micro-IDT electrodes and silver IDT electrodes patterns were developed using AutoCAD 2D and printed on the Kapton (polyimide sheet) flexible substrate using the home-made nano-conductive inks with the help of EpsonT60 commercial piezo-head-based drop-on demand technology printer with standard printing options.

The proposed novel method is able to print heater patterns and IDT electrode patterns of approximately 12 µm and approximately 1 µm thickness, respectively, on flexible substrate using the home-made nano-conductive inks of carbon and silver by using a commercial low-cost printer. The home-made nano-conductive inks can be re-used for multiple prints up to six months shelf life. The resistance of the carbon heater was measured as 88 O under normal atmospheric condition. The novel flexible carbon heater was tested for its functionality and found to be satisfactory. The resistance of the silver IDT flexible electrodes was measured as 9.5 O which is better than the earlier works carried out in this paper.

The main challenge is associated with cleaning of printing ink ejection system in the existing commercial printers. The customization of the existing printer in the near future can minimize the printing challenges.

The novel ink-jet printing technology proposed in this work is cost-effective, capable of achieving bulk production of flexible sensor elements, and consumes the least device fabrication time and high material yielding. The printing can be done with commercial piezo-head-based ink-jet printers with custom-prepared nano-conductive inks. There is a huge market potential for this paper.

Both the carbon heaters and silver IDT electrodes were printed on Kapton flexible substrate by using the commercial printer for the first time. The paper is promising the revolution in flexible low-cost sensor fabrication for mass production, and it is an alternate for thin film and thick sensor fabrication methods. The future of sensor fabrication technology will be the ink-jet printing method. In this paper, the research developments of flexible carbon heaters and flexible silver IDT electrodes for the time are reported. The characterization of carbon heaters and silver IDT electrodes were carried out and confirmed that the results are favourable for gas sensor applications.

Recent years have seen a rapid development of ink‐jet printing technology. This paper reviews the state‐of‐the‐art in ink‐jet printing technology and gives an overview of ink‐jet printing into the immediate future. The focus is placed on various applications of jet printing technology. The potential of applying jetting technology in the conventionally surface coating dominated applications will also be explored.

Just a few years ago, the laser printer was a new and rather expensive gadget with a promising but unknown future. Today, many laser printers sell on the street for less than $1000. They are fast and reliable, and can produce a variety of high‐quality output. In fact, laser printers now provide a base‐line against which other types of printers should be compared. This article discusses the principal non‐laser types of printers, including dot‐matrix, daisy‐wheel, and ink‐jet printers. Examples of currently available dot‐matrix and ink‐jet printers are discussed.

The purpose of this paper is to prepare anionically surface‐modified organic pigment/binder ink jet inks for printing on chitosan‐pre‐treated silk fabrics.

Anionically surface‐modified organic pigment/binder ink jet inks were prepared in four colours (cyan, magenta, yellow and black). The pigment‐to‐binder ratio was controlled at 1:6.4 for the cyan, magenta and yellow inks, and 1:3.4 for the black ink. Ink formulations (by weight) were assembled and mixed as follows: 8 per cent pigment dispersion, 10 per cent diethylene glycol, 12 per cent glycerol, 5 per cent urea, 10 per cent polyacrylate emulsion binder and 55 per cent deionised water. They were characterised in terms of their particle size, zeta‐potential, particle morphology, viscosity, surface tension and pH. The inks were printed onto silk or the chitosan pre‐treated silk fabrics using a piezo‐type ink jet printer. The fabrics were then heat cured and analysed for the effect of chitosan pre‐treatment on colour gamut, wash fastness and crock fastness.

The formulated ink jet inks yielded an acceptably good ink jetting reliability, one‐year stability and printability. The chitosan pre‐treated silk fabrics gave a wider colour gamut and colour saturation than the non‐treated one. Crock fastness and wash fastness of the chitosan pre‐treated fabrics were relatively better than those of non‐treated fabrics.

The surface‐modified pigments are transparent and thus their inks printed on the chitosan pre‐treated fabrics produced slightly low K/S values of cyan, magenta, yellow, and black colours because the limited chitosan concentration in the pre‐treatment is controlled by its solubility in acidic solution. The higher loading of chitosan pre‐treatment gave higher K/S values and a stiffer touch of the fabrics.

The water‐based pigmented inks having the sulphonate group on the pigment surface can be printed on the fabric surface pre‐treated with chitosan molecules which have the protonated amino groups to give good colour appearance. It is anticipated that this type of ink can be applied to any textile surface which has been pre‐treated with the protonated chitosan.

The modified organic pigments having the sulphonate group on their surface can be used to produce novel water‐based ink jet inks which can print on the chitosan pre‐treated silk fabric. Ionic interactions between the sulphonate group of the pigment and protonated amino groups of chitosan in conjunction with polyacrylate binder enhance colour strength, widen colour gamut and chroma, and produce good adhesion for fabric operational properties such as wash fastness and crock fastness.

This paper aims to present combination of poly-jet technology and ink-jet technology in a multidisciplinary way in order to exploit advantages of these rapid prototyping techniques in manufacturing a demonstrator device – a variable interdigital capacitor.

The platform of 3D complex geometry, with optimized design and cavity under the capacitor's fingers (plates), was fabricated using Alaris 3D printer, whereas silver conductive segments were fabricated using Dimatix ink-jet printer and thanks to the mechanical flexibility the platform has been covered using these segments.

When one side of the capacitor's structure changes angular position (in the range from 0 to 90°) with reference to the fixed part, the variation in total capacitance is obtained. The total capacitance decreases (in the range from 20.2 to 1.5 pF) with decrease in effective overlapping area for the variation of angular position from 0 to 90° The maximum measured tuning ratio for the proposed design of the variable capacitor was 13.5:1.

Presented variable capacitor can be used for detection angular position in the range from 0 to 90°.

The new horizon has been opened combining the rapid prototyping equipment in electronics and mechanical engineering in an interdisciplinary way to manufacture, for the first time, variable capacitor using poly-jet and ink-jet technologies. These techniques do not require higher mask counts which makes the fabrication fast and cost-effective.

This work, for the first time, demonstrates the combination of ALARIS 30 3D printer and Dimatix DMP-3000 materials deposition printer in order to fabricate the interdigital capacitor with complex 3D geometry. ALARIS 3D printer has been used for manufacturing plastic platform (with the possibility to precisely adjust angular position of one comb related to another) and Dimatix printer has been used to print silver conductive inks on flexible substrates (Kapton film), and this mechanically flexible structure was used to cover capacitor's fingers on the platform (assembly).

The PCB industry is quickly gearing up for the digital printing age. While photo imaging and screen‐printing have been commonly used as recognized and established techniques in the PCB industry, their high tooling costs and time‐consuming procedures are willingly exchanged by digital printing, following the establishment of this technology both in everyday office uses and in a variety of industrial applications. In the PCB industry, a number of companies have recently begun to offer various digital printing system configurations. This paper discusses the basic requirements of PCB ink‐jet printing systems. Possible solutions and basic system engineering considerations are presented, to show the optimal system configuration.

The British Post Office uses a phosphorescent machine readable code to enable letters to be sorted automatically. The phosphorescent material is printed in the form of a dot pattern in two rows across the face of the envelope. When activated by passing the latter under an Ultra‐violet light the phospor dots will start to glow and will continue glowing for some time after leaving the activating light source. This afterglow is read by a photodetector and the code pattern is interpreted by the machine electronics which instructs the machine mechanics to place the letter in the correct sortation box.

This paper will review digital ink‐jet printing on textiles and the advantages it offers to textile industry and consumers in comparison with conventional printing. The paper also reports on some of the results of a large project, which has been undertaken in the University of Leeds to address a number of issues concerning the problems associated with this technique. One of the important issues associated with digital ink‐jet printing on textiles is speed and reliability, as this has commercial implications for the industry. The research carried out in Leeds has addressed this problem and solutions are proposed which will be covered in detail in this paper. Further research has also been carried out to establish the issues surrounding digital ink‐jet printing and print quality when different types of designs are being printed. The paper will address the results of this research on quality assessment of digital ink‐jet printing on textiles.

To review opportunities for use of digital printing in the printed circuit board (PCB) industry and to introduce background to ink jet printing, process development and applications in order to reduce costs, enhance efficiency and to enable PCB producers to operate in a more sustainable and flexible manner.

This paper has been written to provide a review of ink jet printing applications in the PCB industry. Ink jet print technology background, ink development and the processes made possible by ink and print head improvements have been described together with a description of the benefits available through digital printing.

It was found that there have been significant developments over recent years in both hardware technology (print heads and accurate print platforms) as well as improvements in the design of inks both for ink jet print performance and functional characteristics. These improvements have been integrated to provide an exciting new technology which can be applied in the manufacture of PCBs to reduce manufacturing costs and increase flexibility of manufacture.

The value of the paper lies in its ability to provide information on the scope of opportunities for ink jet printing in the PCB manufacturing process through the use of a range of new inks having specific properties. The design and development of highly accurate machinery provides the opportunity to attain the desired print resolution.

Presents a technology forecast for ink‐jet head technology in 3D printers used in rapid prototyping. Gathers information via an expert opinion survey and from the Georgia Tech Library and the World Wide Web about future development and possible impacts. Shows that the technology is still in its infancy but receiving increased interest. Predicts the path the market may take and presents an outcome table for impact assessment. Considers the potential role of public policy in the technology development.