The swelling of soft coatings on a tough substrate immersed in solvent is investigated. Equilibrium aspects of the coating deformation due to swelling as well as its kinetics have been explored; in particular, the appearance of patterns on the originally smooth surface of the swollen film is described and modeled. The patterns are the result of a mechanical instability such as buckling or wrinkling. The time dependence of the wrinkles height is measured and, by using the energy dissipation criterion for wrinkle spread, the ratio of the adhesion energy by the bulk modulus is determined as a function of swelling time.