Magnetic tape cassette, guide roller, and a method of manufacturing a guide roller

摘要

A magnetic tape cassette and a guide roller in which the magnetic tape can stably travel and the magnetic head can read/write the record correctly, and a method of manufacturing the guide roller are provided. The magnetic tape cassette of the present invention comprises a guide roller 106 rotatably supported by the lower cassette half. The guide roller is almost in the shape of a barrel of which a coefficient of curvature T expressed by the expression [1] representing the extent of curvature of the circumferential surface is in the range between 0.001 and 0.01, and comprises a primary molding and injected resin injected within the primary molding for bulging said primary molding into the shape of said barrel shaped cavity that has a largest diameter at the parting line by the injection pressure.