3D inkjet-printed UV-curable inks for multi-functional electromagnetic applications

Inkjet printing of multiple materials is usually processed in multiple steps due to various jetting and curing/sintering conditions. In this paper we report on the development of all inkjet-printed UV-curable electromagnetic responsive inks in a single process, and the electromagnetic characterization of the developed structure. The ink consists of iron oxide (Fe3O4) nanoparticles (nominal particle size 50-100 nm) suspended within a UV curable matrix resin. The viscosity and surface tension of the inks were tuned to sit within the inkjet printability range.Multiple layers of the electromagnetic active ink were printed alongside passive UV-curable ink in a single manufacturing process to form a multi-material waffle shape. The real permittivity of the cured passive ink, active ink and waffle structure at a frequency of 8-12 GHz were 2.25, 2.73 and 2.65 F/m, respectively. This shows the potential of additive manufacturing (AM) to form multi-material structures with tunable electromagnetic properties.