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Purpose – Wearable electronic devices have emerged which require compact, flexible power storage devices such as batteries and supercapacitors. Recently, energy storage devices have been developed based on supercapacitor threads. However, current supercapacitor energy storage threads which use electrolytes based on aqueous gels have a 1 V potential window. This is much lower than the voltage required by most electronic devices. This current contribution presents an approach for fabricating a multilayer supercapacitor working as a circuit unit, in which series combinations of the multiple layer structures can achieve a higher potential window, which can better meet the needs of wearable electronic devices. Design/methodology/approach – Two-capacitive layer thread supercapacitors were fabricated using a semi-automatic dip coating method by coating two capacitive layers sequentially on a 50 μm stainless steel core wire, each capacitive layer includes ink, aqueous-based gel electrolyte and silver conductive paint layers. Findings – Two capacitive layers of the single thread supercapacitor can work independently, or as combination circuits – parallel and series. Cyclic voltammograms showed that all flexible circuits have high electrochemical stability. For the case of series circuit configuration, with H3PO-polyvinyl alcohol (PVA) gel electrolyte, a working potential window of 2 V was achieved. Originality/value – A flexible single thread supercapacitor of multilayer structure, with working voltage above 1 V in H3PO4-PVA gel electrolyte, has not been reported before. A semi-automatic dip coating setup used to process the thread supercapacitor has high potential for transfer to an industrial environment for mass production.

PurposeMicrocontact printing is a process used to print high‐resolution protein arrays for biosensors. The paper aims to investigate using these techniques to print electrically conductive fine line structures for electroluminescent (E/L) light sources.Design/methodology/approachThe viability of using microcontact printing as a process for electronics fabrication is investigated. Polydimethylsiloxane stamps inked with alkanethiol compounds form self‐assembled monolayers on substrate surfaces, acting as the resist to subsequent etching processes. The printed lines are characterized with regard to their performance as high‐electric field generators in electroluminescent displays.FindingsIt has been demonstrated that microcontact printing is a cheap, repeatable process for fabricating electronic devices. The results demonstrate the viability of the process to fabricate electric field generator structures for E/L light sources with reduced driving voltages.Originality/valueThe paper demonstrates that microcontact printing can produce electrically conductive fine‐line structures with high resolution, confirming its viability in printed electronics manufacture.

PurposeIt has been shown that circuit interconnects and various passive components can be fabricated on a variety of flexible substrates using the offset lithographic process. This paper reports on a feasibility study investigating the manufacture of voltaic cells deposited via offset lithography.Design/methodology/approachThe Leclanché cell, an established battery chemistry, was chosen as an appropriate technology for adaptation to the offset lithographic process. Development of inks with appropriate rheological properties for lithographic printing was undertaken. Zinc and carbon electrodes were fabricated with silver‐based current collectors. Electrolyte composition was investigated along with separator materials.FindingsZinc and carbon‐based inks have been produced which result in deposited material appropriate for use as electrodes. A separator material soaked in electrolyte has been combined with these electrode structures and an MnO2 paste to form a voltaic cell. A printed battery, made up of these voltaic cells, with a capacity greater than 8 mAh at 6 V has been produced.Originality/valueThe fabrication of voltaic cells via offset lithography facilitates the production of electronic systems with power sources provided by the same printing process. This paper provides information of interest to all those involved in the developing industry of printed and flexible electronics.

Many people believe that Eisler invented the printed circuit board (PCB) in the mid‐1930s, but the origins actually lie nearly before 50 years this. If this is true then who invented the PCB? This review offers an alternative view of the history of the PCB including early developments and contributions from the world of art and printing, through innovations in science and engineering to the key developments of the modern electronics industry.

Conductive lithographic films (CLF) are an emerging fabrication process for electronic interconnect and a range of passive component structures. This paper reviews the manufacture, properties and applications of CLF conductors, and discusses other lithographically deposited electronic materials including resistive, dielectric and ferrite films. Recent developments in CLF technology, including multilayer structures and concurrent printing of interconnect with printed passive components, are presented.

This paper concerns a novel process for forming additive copper interconnect on flexible substrates via printing and plating processes. Building on the established conductive lithographic film and CLF plating seeding technologies, the described process enables low‐cost substitutes for existing flexible electronic wiring boards to be manufactured without precious metals.