ANCHORING OF A LIQUID BY A CHEMICAL DISCO NTINUITY ON A SURFACE

Using the Wilhelmy method, we studied the behaviour of a liquid edge o n the chemical dicontinuity between two solid surfaces with different wettabilities. We observed and discussed two different regimes : when the liquid covered the hydrophilic part, the contact line was pinned o n the boundary as long as the contact angle ranged between limits that we determined; on the contrary, when the liquid was on the hydrophobi c part, the contact line was unstable on the boundary.