Contact angle hysteresis on rough hydrophobic surfaces

In this short note, we report a quantitative investigation of the hysteresis of the Cassie and Wenzel drops on a given rough surface. The Cassie drop shows Much less hysteresis compared to a Wenzel drop and is therefore preferred in applications involving moving droplets. The experimental measurements are compared with the various theoretical models for the apparent contact angles and recommendations are made. (C) 2004 Elsevier B.V. All rights reserved.