The Jet Behavior of Non-Contact Electric Field-Driven Jet Micro 3D Printing

Electrohydrodynamic (EHD) jet printing is a promising method for high-resolution manufacturing; however, it often suffers from jet deflection owing to the accumulation of residual charges within printed structures. These residual charges lead to jet deflection. This study introduces a novel noncontact electric field-driven (NEFD) jet micro 3D printing technique to address these challenges. By decoupling the high-voltage power supply from both the printing material and substrate, NEFD jet micro 3D printing eliminates the pathway for charge injection into the printing material, reducing residual charges by a factor of five or more compared to EHD jet printing. Our research revealed an inherent attractive force between the material jet and previously deposited material, regardless of the material used. Furthermore, we demonstrate that employing a pre-defined allowance printing strategy during fabrication reduces the standard deviation of actual fiber spacing values from 11.4 µm to 1.5 µm, thereby improving the fiber spacing consistency. This enhanced control enabled the successful fabrication of line patterns with 20 ± 1 µm fiber diameters and 61.1 ± 1.9 µm fiber spacing, demonstrating the feasibility of NEFD jet micro 3D printing. This technique offers a novel solution for mitigating the challenges associated with electric fields and charge accumulation in EHD jet printing, paving the way for enhanced resolution and material compatibility in micro-/nanoscale additive manufacturing.