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Microcontact 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.

The 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.

It 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.

The paper demonstrates that microcontact printing can produce electrically conductive fine‐line structures with high resolution, confirming its viability in printed electronics manufacture.

New types of substrates were used for fabrication of printed electroluminescent structures. Polymer foils mainly used as substrates for such optoelectronic elements were replaced with paper and textiles. Printing on non-transparent substrate requires elaboration of printed transparent electrode, while usually polyester foils with sputtered ITO transparent electrodes are used. The paper aims to discuss these issues.

Electroluminescent structures were fabricated with elaborated polymer compositions filled with nanomaterials, such as carbon nanotubes and graphene platelets, dielectric and luminophore nanopowders. Structures were printed as “reverse stack”, where transparent electrode is printed on top of the last luminophore layer. For that carbon nanotubes and graphene platelets filled composition was used, deposited with spray-coating technique.

Main issue with new substrates is proper wetting with the use of screen-printing pastes, and much higher roughness especially for textiles.

Fully functional structures were obtained, but several disadvantages were observed that needs to be eliminated in further studies.

Demanding technical requirements of thin film electroluminescent display modules and hard competition in electronic display markets set boundaries for the setting of goals in the development of an extremely thin display module. To meet the targets the problems of electronic packaging concepts had to be considered from the point of view of total optimisation. As a result, a packaging concept was developed which had an influence on all design decisions starting from the end user's requirements and extending to the selection of a special semiconductor manufacturing process. A set of customised high voltage integrated driving circuits was developed. High density interconnection problems were solved by the tape automated bonding of semiconductors and a single‐sided two‐layer polymer thick film circuit board. Throughout the assembly process surface‐mounted components and reflow soldering methods were applied to form a large area printed polymer hybrid module. Viable volume production methods for a flat dot‐matrix display could be suggested.

The paper aims to present the research results related to transparent heating elements made from carbon nanomaterials. Heating elements were fabricated only with cost-effective techniques with the aim to be easily implemented in large area applications. Presented materials and methods are an interesting alternative to vacuum deposition of transparent resistive layers and etching of low-resistive patterns. Fabricated heating elements were designed to be used as de-icing structures in roof-top windows.

The paper presents the research results related to transparent heating elements made from carbon nanomaterials. Heating elements were fabricated only with cost-effective techniques with the aim to be easily implemented in large area applications. Presented materials and methods are an interesting alternative to vacuum deposition of transparent resistive layers and etching of low-resistive patterns. Fabricated heating elements were designed to be used as de-icing structures in roof-top windows.

The sheet resistance of obtained layers was between 9 and 11 kΩ/□; however, double-walled carbon nanotubes showed significantly higher optical transmission (around 70 per cent) than graphene nanoplatelets (around 55 per cent for visible and near infrared range). The amount of polymer resin had the influence on the paints stability, electrical properties and coatings adhesion.

Results show a novel method of fabrication of a large area and transparent heating elements with tunable resistance done through the change of spray coating paint composition.

The purpose of this paper is to focus on the development of highly efficient emission materials for light‐emitting diodes (LEDs).

The equilibrium geometries of silole‐based derivatives are optimised by means of DFT/B3LYP method with the 6‐31G(d) basis set in this paper. The geometries of single‐excitation are optimised using the ab initio configuration interaction with single excitations/6‐31G(d), the first singlet excited states and optical properties are calculated by using time‐dependent density‐functional theory based on the 6‐31G(d) basis set.

The highest occupied molecular orbital and lowest unoccupied molecular orbital suffer larger effects from the variation of the substituent groups of methyls and phenyls. The absorption wavelengths of all the cases are similar, but the emission wavelengths are significantly different.

Solid‐state stacking effect is not included in this paper.

In view of the application of silole‐based derivatives systems, the control of photophysical properties and electronic structures by structural modification is relevant to further molecular design.

The aims of this paper are to investigate the influence of direct current (DC) electric field on separation and orientation of carbon nanotubes (CNTs) in spray-coated layers and apply this method to the fabrication of elastic and transparent electrodes. The orientation of CNTs in the form of paths in the direction of electrical conduction should increase the electrode conductivity without decreasing its optical transmission.

Materials are deposited using vacuum-free, ultra-fine nozzle spray coating technique, easily applicable for large-scale production. After the deposition of carbon nanomaterials, nanoparticles are oriented in the electric field and initially cured with infrared halogen lamp to evaporate solvents and preserve orientation of the nanoparticles in the deposited layer. Afterwards, layers are cured in a chamber dryer to obtain desired properties. Nanoparticles orientation and carbon nanomaterials separation via DC electric field are analysed, and the optical and electrical properties of prepared electrodes are measured.

Experiments described in this paper showed that DC electric field can be applied provide separation and orientation of CNTs and combined with spray coating technique, can be used as additional tool for tuning the conductivity of flexible and transparent electrodes by decreasing the sheet resistance about five times.

The results showed that spray coating combined with electric field orientation is a promising solution of obtaining elastic and transparent electrodes with oriented carbon particles. According to the authors’ knowledge, none of the experiments was directed to obtain DC electric field-oriented transparent layers produced with the use of spray coating technique.

The inorganic high‐luminosity electroluminescent (EL) panel used in this study is a distributed‐type EL panel, which can be produced using a printing technique. We obtained a panel with a high luminosity of 7940 cd/m2 at 6 kHz. In addition, we believed that the panel temperature and luminosity of this panel were closely related. Therefore, we considered the relationship between the temperature change in the dielectric layer and the luminosity since this relationship is responsible for the supply of electric charge to the phosphor layer. A change in the amount of electric charge by heating in a high‐voltage domain originates at the Curie point of BaTiO3 ferroelectric particles. This indicates that the influence of BaTiO3 was strong.

This paper concerns an all‐solid‐state, high‐contrast electroluminescent (EL) flat panel display which is becoming the potential for multifunctional avionic displays. In this ACTFEL (a.c. thin film electroluminescent flat panel) device, an active layer, doped with manganese (ZnS:Mn) is sandwiched between the two dielectric layers followed by conductive layers. All the layers are transparent except the back conductive layer. In the basic mode of operation, an alternating voltage is applied across any two crossing electrodes. When this voltage exceeds the ‘threshold voltage’, light is emitted from the active layer. EL mechanism (the generation of electrons, acceleration of these electrons to optical energies, and collision excitation of the Mn ions yielding light emission) occurs within the film or at the surface of the ZnS:Mn layer. A bright yellow light, in the visible region and with a relatively broad spectrum, is emitted. The TFEL display's thinness, compactness, low weight, moderately low power requirements and durability are its prime advantages. The characteristics of various thin films utilised in TFEL have been studied, and the data in this paper show the optimum requirements for luminance, efficiency and reliability of the light emission in ACTFEL.

Purpose This study aims to apply the impedance spectroscopy (IS) for analyzing the electrical behavior and extracting the equivalent circuit of single-layer flexible organic light-emitting diodes (OLEDs) with poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) anode.

The preliminary ultraviolet (UV) treatment of the flexible substrate of polyethylene terephthalate (PET) influenced the conductivity of PEDOT:PSS anodes.

The IS showed that the OLED with UV-treated PET/PEDOT:PSS anodes had lower values of the contact resistance and higher value of the interface capacitance.

The obtained data were used for modeling of flexible OLEDs with polymeric anodes and calculation of important display parameters such as pixel refresh ratio, signal delays and energy losses due to contact resistances. These parameters were compared for PEDOT:PSS anodes deposited on PET treated and non-treated by UV.