Abstract
The typically elongated shape of droplets on chemically
microstriped surfaces has been suggested to depend strongly on
the kinetics during deposition. Here, we unequivocally establish the
importance of impact kinetics by comparing the geometry of pico- to
microliter droplets deposited from an inkjet nozzle with those
obtained by conventional deposition from a syringe. For large Weber
numbers, the strongly enhanced spreading during the impact in
combination with direction-dependent pinning of the contact line
gives rise to more spherical droplets with a low aspect ratio. The
impact energy can be minimized by the prolonged firing of small
picoliter droplets to form larger droplets or, as shown in the past, by
using high-viscosity liquids. In the first case, the impact energy is absorbed by the liquid already present, therewith reducing the
impact diameter and consequently forming markedly more elongated droplets
Original language | English |
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Pages (from-to) | 13137-13142 |
Number of pages | 6 |
Journal | Langmuir |
Volume | 28 |
Issue number | 37 |
DOIs | |
Publication status | Published - 2012 |
Keywords
- 22/4 OA procedure