3D Printed Microstructures Erasable by Darkness

To advance the applications of direct laser writing (DLW), adaptability of the printed structure is critical, prompting a shift toward printing structures that are comprised of different materials, and/or can be partially or fully erased on demand. However, most structures that contain these features are often printed by complex processes or require harsh developing techniques. Herein, a unique photoresist for DLW is introduced that is capable of printing 3D microstructures that can be erased by exposure to darkness. Specifically, microstructures based on light-stabilized dynamic materials are fabricated that remain stable when continously irradiated with green light, but degrade once the light source is switched off. The degradation and light stabilization properties of the printed materials are analyzed in-depth by time-lapse scanning electron microscopy. It is demonstrated that these resists can be used to impart responsive behavior onto the printed structure, and -critically- as a temporary locking mechanism to control the release of moving structural features.