Digital printing processes are gaining more and more interest as an approach to implement electrical functionality (conductive patterns, sensors etc.) on different types of substrate materials. Focusing on the inkjet-printing process, the paper presents results that were gathered with-in the research project “FKIA”, funded by the Bavarian Research Foundation. In the paper, the applicability of inkjet printing of silver nanoparticle ink on technical thermoplastics substrate materials commonly used in automotive applications such as glass fiber filled PA, but also on phenolic paper substrates (FR-2) is investigated. In this context, the influence of the surface roughness of the molding tool on the printing results was examined. Besides thermal sintering of nanoparticles, photonic sintering as one alternative approach is discussed. In addition, the long-term behavior of the produced conductor tracks was investigated. Parts were exposed to thermal cycling between −20°C and +100° for 1500 cycles. Besides the stability of the electrical properties also the mechanical stability of the metallic layers on the different substrates was compared with the findings prior to any exposure.