DRILL

PROBLEM TO BE SOLVED: To provide a drill that sufficiently secures a biting performance to a material to be cut when drilling a hole with a drill, and shortens the time necessary for stabilizing a cutting resistance.SOLUTION: In the drill, a lip clearance angle of a cutting blade formed from a chisel edge corner to an outer periphery corner, is continuously reduced from the chisel edge corner toward the outer periphery corner. The lip clearance angle at the chisel edge corner is controlled between more than 15° and 25° or less, and also at the outer periphery corner between 3° or more and less than 8°.