US Patent 7967533 Surface-coated cutting tool

A surface-coated cutting tool includes a coating layer (108) formed on a substrate (104), wherein assuming that the average thickness of the coating layer (108) on a first surface (106) and a second surface (107) of the substrate (104) is A, a difference between the maximum and minimum thicknesses of the coating layer (108) is 0.04×A or less. Also, a surface-coated cutting tool includes a coating layer (108) formed on a substrate (104), wherein assuming that the average thickness of the coating layer (108) on a first surface (106) of the substrate (104) is B1, and the average thickness of the coating layer (108) on a second surface (107) of the substrate (104) is B2, a value obtained by dividing an absolute difference value between B1 and B2 by a larger value of B1 and B2 is 0.04 or less.