Roughening transition in a moving contact line

The nonequilibrium dynamics of the deformation of a moving contact line on a disordered substrate was studied. It was found that the relaxation spectrum of a moving contact line is the same as the equilibrium case, but the characteristic relaxation velocity depends on v: It decreases with v until at the critical velocity corresponding to the coating transition it vanishes identically. The progressively slow relaxation of a disordered contact line near the coating transition is in agreement with a nucleation picture of the phase transition. Coating transition was actually understood in terms of a roughening transition of the contact line on the disordered substrate