Control of local wetting by microscopic particles
Résumé
We perform experiments to investigate how particles of micro-meter size modify the wetting of a completely wettable solid surface. The motion of a macroscopic contact line (MCL) is observed to be altered in the region surrounding the particles. The MCL is accelerated locally by a single particle to advance approximately 10 times faster than that in the absence of the particle. Different geometrical arrangements of particles produce different wetting speeds and different MCL shapes through multiple MCL-particle interactions. These results suggest a method to control the wetting without surface patterning by chemical treatment.