Entrainment of liquid films by vertically moving thin rods

Abstract

When a thin rod is withdrawn vertically from a liquid bath a film of that liquid adheres to the rod. A short review of the theories describing this process is given. The application of these theories to three model systems using glycerol solution, kerosene and an oil as the coating liquids is discussed. The effect of surface active agents on the equilibrium film thickness is explained in terms of additional forces at the liquid-air interface impeding film drainage.