抄録
Surface of Taiheiyo coal was observed by an atomic force microscope (AFM) equipped with an environment-controlled chamber. Surface properties and mechanical properties of coal under inert atmosphere were discussed. In coal surface, three components are recognized; a layered structure at several microns, unstructured and soft component, and fibrous component which gives a long range repulsive force Such unusual long range force is elucidated by comparing force curve of coal and thermally treated char.