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arXiv · 1101.0915

Wetting on smooth micropatterned defects

Damien Debuisson·Renaud Dufour·Vincent Senez·Steve Arscott
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Abstract

We develop a model which predicts the contact angle hysteresis introduced by smooth micropatterned defects. The defects are modeled by a smooth function and the contact angle hysteresis is explained using a tangent line solution. When the liquid micro-meniscus touches both sides of the defect simultaneously, depinning of the contact line occurs. The defects are fabricated using a photoresist and experimental results confirm the model. An important point is that the model is scale-independent, i.e. the contact angle hysteresis is dependent on the aspect ratio of the function, not on its absolute size; this could have implications for natural surface defects.

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Damien Debuisson, Renaud Dufour, Vincent Senez, Steve Arscott. 2011-01-05. Wetting on smooth micropatterned defects. https://doi.org/10.1063/1.3657140

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