The rate of diffusion of slip additive to the surface of the polymer film varies as a function of chemical structure. The lower molecular weight oleamide migrates to the film surface more rapidly and is often referred to as a 'fast blooming' slip (see Figure 1). Although 'slow blooming' erucamide develops its lubricating effect at a slower rate initially, after 4-6 hours it produces lower COF values than equal quantities of oleamide (see Figure 1 and Figure 2).