DISK CARTRIDGE

PROBLEM TO BE SOLVED: To simplify the manufacturing processes by integrally forming a shutter plate and a slider and forming the tip part of engaging structure portion with thickness which gradually becomes thinner toward the inside of the cartridge case to load such integrated shutter plate and slider to the cartridge case with one action. SOLUTION: The shutter plates 16a, 16b and slider 17 are integrally formed of synthetic resin by the ejection molding method to form an integrated shutter/ slider body. The front side engaging structure tip part 26 of the shutter/slider integrated body is engaged with the engaging portion structure element 22 formed along one end edge of the upper half 11 and lower half 12 of the cartridge case and these are held to slide along one end edge of the cartridge case. Thickness of the tip part 26 is thinner than the narrowest gap g2 of the engaging portion and the tip part 26 easily passes through the narrow gap g2, allowing insertion of cartridge with one action when adequate pressure is applied owing to elastic deformation of the front side engaging structure 24 and slit structure 40.