Electrohydrodynamic (EHD) Printing has long been known as a potentially superior printing technology compared to conventional inkjet. Back in the 80s, EHD was explored for graphical applications by major players but has long since been abandoned. Beginning of the century, new activities have emerged mainly in relation to emerging industrial applications like printed electronics. The problems that keep the technology from becoming industrially relevant remain the same. EHD printheads are not manufacturable with large nozzle counts, mainly because of cross-talk issues, unbearably high driving voltages as well as general long-term stability challenges.
Through technology from Scrona, the first MEMS-based EHD printheads have been created that eliminate all these problems at once. Scrona’s new EHD printheads contain nozzles at a density that can be more than five times higher than that of modern piezo-driven inkjet heads and they can be individually operated with less than 100V which makes them compatible with massively scaled and commercially available driving electronics. Specialized nozzle architectures not only keep liquid in place, but also strongly reduce clogging issues by a highly efficient recirculation flow.
During the talk, Patrick will discuss key success factors and examples that demonstrate the unseen performance in terms of printing resolution and droplet placement precision, all of that in direct connection to applications in the printed electronics realm.
While other additive manufacturing technologies operating at sub-5µm printing resolution generally require extremely precise control of printhead-substrate distance, Patrick will show how a printhead can place droplets with sub-micron precision even at distances of 1mm and more, and the possibility to adapt nozzle size to make them compatible to various demands in terms of resolution, ink viscosity and particle size. Results will be presented on a newly developed printhead class adapted for high-viscosity printing. By scaling the nozzle size and slight design adaptations, printing of inks up to 10Pa.s is possible, at droplet sizes that in principle align with those that standard inkjet printheads have achieved with inks a thousand times less viscous.
Short bio of Patrick Galliker / CEO
World-renowned expert in the area of electrohydrodynamic printing, and in this field has filed 13 patent families and is main author of one of the most cited scientific publications. Received a PhD from the mechanical engineering department of ETH Zurich, while simultaneously obtaining a master of advanced studies in management, technology and economics from the same school. By nature, combines a vivid interest in technology and entrepreneurship and has therefore not only acted as the main inventor of Scrona’s multi-nozzle MEMS platform but also led several financing rounds and grant proposals that provided the company with more than 10 million dollars in funding so far.
