ABSTRACT
This chapter presents the next level of complexity and treats both the statics and dynamics of three coexisting phases in the context of the topic of wetting. It also treats the problem in the classical manner and shows how a simple analysis of the competing interfacial tensions determines the contact angle of the fluid drop on the solid. The chapter illustrates how the classical theory is related to a more microscopic description of the problem and in particular, uses the theory of the profile of the liquid layer on the solid substrate to relate the contact angle that the macroscopic drop makes with the solid, to the thickness of a thin layer of fluid that covers the substrate in the region between the drops. Finally, the chapter discusses the dynamics of wetting since many experimental situations involve nonequilibrium effects, and mentions recent work on pattern formation in wetting.
