Dynamics of Dewetting on a Surface of Substrate

Abstract

The Dynamics of droplets on the surface of substrate, i.e., impact, wetting and dewetting, were studied abundantly. These phenomena are not only interesting from the viewpoint of basic science but also important for industrial applications, for example, designs of ink in inkjet-printers or of pesticides.

When a droplet is pure and does not contain the chemicals which interact with the surface of a substrate, the impact, wetting and dewetting are simple. In this case, the shape of a droplet will approach the equilibrium one, depending on the contact angle between a droplet and a substrate. When a droplet contains such chemicals that interact with the surface of a substrate, however, the wetting and dewetting become more complicated. And for almost all industrial applications, such complicated phenomena, which are called as reactive dewetting, should be controlled. Reactive dewetting is observed when a droplet contains chemicals (surfactants) which interact with the surface of a substrate. Here, we will show the experimental results regarding reactive dewetting and analyze them semi-quantitatively. We will also consider the application potency of these results.