High-Resolution\nTotal Internal Reflection-Based Structural\nColoration by Electrohydrodynamic Jet Printing of Transparent Polyethylene\nGlycol Microdomes

Total internal reflection (TIR)-based\nstructural coloration\nis\na brilliant strategy to overcome the need for periodic nanostructures\nand complex fabrication processes. Light entering the microdome structure\nundergoes TIR, and owing to varying reflection paths, it exhibits\na color that changes with the microdome size. Although solution-based\nprinting techniques have been proposed to achieve this effect, they\nfall short of full-color realization owing to resolution limitations.\nHerein, we achieved 3628 dpi of full-color and high-resolution structural\ncolor images by printing transparent microdome structures with 1.2–9.9\nμm diameter using electrohydrodynamic (EHD) jet printing. Additionally,\nhigh-resolution EHD jet-printed structural color images display complex\nencoded information, enhancing the anticounterfeiting effectiveness\nthrough their fabrication simplicity and precise control over the\nmicrodome size. Because of these advantages, this TIR-based structural\ncoloration technique with EHD jet printing is highly suitable for\nanticounterfeiting applications.