Array-Nozzle EHD Print Head and Its Drop-on-Demand Experimentation

EHD (ElectroHydroDynamic) printing has critical merits in printing micro/nano size patterns compared to other inkjet printing technologies; however, the development of multi-nozzle EHD print heads is essential for high throughput printing and commercialization of this inkjet head technology. This paper introduces a novel nozzle array EHD print head that features control electrodes designed for electrostatic ejection and screening to reduce electric field interference. The printer head consists of a nozzle plate, an insulator, and control electrodes, and it is assembled by stacking the components. Experimental prototypes were fabricated by using micro-CNC, EDM, and ceramic processing. Two experiments were conducted to verify functions of the head, i.e. (i) drop-on-demand printing without the control electrodes and (ii) printing with the control electrodes. Preliminary experimental results show a successful drop-on-demand printing with an array of nozzles. The control electrodes were used to reduce the operating voltage and electric field interference among the nozzle array.