Design and simulation of a hybrid inkjet printhead for ejecting high viscous inks

Printing high-viscosity inks continues to remain a challenge in inkjet technology, and thus far, extensive numerical simulations have been performed to resolve this issue. In this paper, we present a novel hybrid inkjet printhead that combines piezoelectric and electrohydrodynamic (EHD) forces. The hybrid inkjet printhead is designed using multi-physics numerical simulation technology and by investigating jetting high-viscous ink. The proposed method enables precise control of the droplet volume and velocity. We also investigated the performance of our hybrid inkjet printhead and optimized the piezoelectric and EHD waveforms with rising, dwell, and falling times. Further, we designed an EHD driving device to generate the EHD jetting force. We used a hybrid inkjet printing simulation to jet a high-viscous ink of up to 100 cp, which confirms that the jetting performance of the hybrid inkjet printing method is superior to that of the existing piezoelectric inkjet printing methods. The proposed high-viscosity hybrid inkjet head technology can be applied to various industrial fields, including display manufacturing processes, semiconductor packaging processes, 3D printing, and manufacturing processes for biomedical artificial structures.