Razor blade with discontinuous teflon film.
Topography and Lateral Force Images

As a typical commercial razor blade is used for cutting the teflon coating on the blade gradually erodes until a thin residual layer is all that remains. The continuity of this layer is difficult to resolve in a topographic image of the surface. With the use of the lateral force imaging mode (LFM), however, the low-friction behavior of the teflon stands out strongly from the relatively higher friction metallic substrate, revealing the degree of dispersion of the teflon. In the LFM image above, the brighter metallic regions are "stickier" than the slippery teflon regions.