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The electrical performance of screen‐printed dry electrodes on thermoplastic polyurethane substrates are evaluated according to their conformance to international standards, skin‐electrode impedance, and ability to gather high quality electrocardiograms. The electrical behavior of seven screen‐printed electrodes (Ag, Ag/PEDOT:PSS, Ag/AgCl, Ag/AgCl/PEDOT:PSS, C, C/AgCl, and PEDOT:PSS) is compared to two commercially available gel electrodes (3M RedDot 50 and Philips NeoLead) which represent the state‐of‐the‐art. After basic standard electrical characterization (electrode‐electrode impedance, DC offset voltage, defibrillation recovery, bias stress, and noise), it is shown that layers like AgCl or PEDOT:PSS help to reduce the contact impedance of dry electrodes. However, the quality of the electrical signal is primarily governed by the skin impedance, which, without physical disruption or preparation, maintains a high impedance. For this reason, the impedance of all screen‐printed dry electrodes allows the collection of electrocardiograms with a quality equal to that of gel electrodes. Dry electrodes, while capable of obtaining similar electrical signal quality also bring the advantages of reusability, comfort, and the capability for long‐term measurements.

In this paper we present elastomeric large-area arrays of pressure sensors based on printed electronics. Two applications are presented to demonstrate the versatility and scalability of the presented technology. The first consists of a shoe inlay with over 700 sensors (5 mm pitch) and the second consists of large-area sensor mat (30 cm × 40 cm) for posture detection. Both designs have been manufactured using sheet-to-sheet screen printing on stretchable polyurethane substrates yielding sensors thinner than 350 μm.

A distributed chemical sensor is developed by coating multiple Bragg gratings in a single glass fiber with chemical responsive coatings. The composition of the coating is tuned to the target chemicals to be measured and the optical response of the coated grating is optimized by changing the coating thickness. Specific recoaters were used to apply the responsive coatings reproducibly onto the glass fibers. The coating compositions can be based on UV curing or solvent based systems. In this paper we show the development and application of a distributed gas sensor for CO 2 , H 2 S and H 2 O that can be used for down-hole monitoring in the oil and gas industry. We have developed a toolbox for the design and modeling of the responsive polymer coatings, and the performance of the actual sensors corresponded well with the predicted behavior.

A study on via drilling and channel scribing on PEN and PET substrates for flexible electronic application is discussed in this paper. For the experiments, both KIF excimer laser (248 nm) and frequency tripled Nd:YAG (355 nm) laser are used. Different measurement techniques like optical microscopy, Dektak profilometer, Confocal microscopy and scanning electron microscopy (SEM) were employed to characterize the quality of the channels and vias. The patterned structures were filled by three different methods using a conductive paste or ink that is cured in an oven at an elevated temperature. The cross-sectional measurements of channels and vias were carried out using SEM to study the uniformity of filling.