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arXiv · 1602.04891

Ring to Mountain Transition in Deposition Pattern of Drying

Xingkun Man·Masao Doi
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Abstract

When a droplet containing a non-volatile component is dried on a substrate, it leaves a ringlike deposit on the substrate. We propose a theory which predicts the deposit distribution based on a model of fluid flow and contact line motion of the droplet. It is shown that the deposition pattern changes continuously from coffee-ring to volcano-like and to mountain-like depending on the mobility of the contact line and the evaporation rate. Analytical expression is given for the peak position of the distribution of deposit left on the substrate.

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Xingkun Man, Masao Doi. 2016-02-16. Ring to Mountain Transition in Deposition Pattern of Drying. https://doi.org/10.1103/physrevlett.116.066101

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