DISK CARTRIDGE

PURPOSE:To improve a dustproof function by forming a swelling part of specific shape by neighboring to a window at a position along the edge of the window. CONSTITUTION:The swelling part 16 is provided in a direction almost intersecting orthogonally to a sliding direction according to the opening/closing of a shutter along the head window 14 of a case main body 10, and the shape of the part is formed within a range not disturbing the opening/closing of the shutter i.e. with width of around 0.1-2.5mm, height of around 0.1-0.5mm, and length almost equal to that of the window, and also, the swelling part is provided at a position separated from the window by 0.1-5mm, thereby, it is possible to prevent the disk stained by the invasion of dust from the head window to the inside of a case, which heightens the dustproof function.