Flexible magnetic disk having an embossed circular hole

摘要

A flexible magnetic disk comprises a jacket and a flexible magnetic disk sheet housed in the jacket. The flexible magnetic disk sheet is provided at the center with a circular hole for engagement with a sheet positioning member of an information writing and read-out apparatus. The jacket has an aperture for exposing the circular hole of the flexible magnetic disk sheet. The peripheral edge portion of the circular hole which comes into contact with the sheet positioning member is embossed to decrease the coefficient of friction of the peripheral edge portion to 0.45 or less, so that the flexible magnetic disk sheet is correctly positioned by the sheet positioning member.