Some properties of pad printed electroconductive elements

Abstract

In this paper pad printed conductive elements using carbon based conductive ink on paper substrate have been analyzed. The investigation was primary directed to checking the possibility to print different elements, using pad printing technique, as narrow as possible but still conductive. The evaluation includes the shape sustainability, thickness and width of printed elements and inevitable resistance, in dependence on the number of wet to wet overprinted layers under predefined curing time. For the research we have printed various lines, straight, curved, right and cut angled in open and closed form, with the width of 50-500 :m. Those elements were single, double and triple printed (wet to wet). The evaluation of printed elements (width and thickness) was carried out using micrographs obtained with optical microscope (magnification of 140×) and Scanning Electron Microscope using image processing software ImageJ. Also, EDS (Energy Dispersive Spectroscopy) analysis was done in order to give a deeper characterisation of used ink. Resistance measurements were carried out using HP 4194A Impedance/Gain-Phase Analyzer. Throughout the experiment we have determined the narrowest conductive line that can be printed under specified printing conditions. The results showed the influence of multiple layer printing on resistance and on the changes in the shape of the elements in terms that multiple layer printing decreases resistance but increases line width.