Droplet Printing Enabled by Cavity Collapse Ejection

The behavior of cavity collapse in liquids is of fundamental
importance
in natural and industrial applications. It is still challenging to
use the phenomenon of cavity collapse ejection in on-demand droplet
printing technology. In this study, we investigate the cavity collapse
ejection phenomenon in the submillimeter to millimeter scale and demonstrate
that the cavity capillary energy is a critical factor affecting the
state of the generated jet. Based on this phenomenon, we developed
a droplet printing technology that can print nanoliter satellite-free
droplets from a millimeter-sized nozzle, which reduces the risk of
nozzle clogging. Using this printing technology, we demonstrated the
printing of a nanoparticle suspension with 60% mass loading. Finally,
we also showcased the printing of various inks for different applications
using this technology, demonstrating the printability of cavity collapse-ejection
printing technology in functional inks and showing potential to be
applied in scenarios such as bioassays, the electronics industry,
and additive manufacturing.