Patent ID: 10441720

Abstract:
Medical syringe having a gasket excellent in sealability and slidability. The syringe includes a hollow cylindrical syringe barrel (11) and a gasket (13) fitted in syringe barrel (11). Gasket (13) includes a main body of an elastic material laminated with an inert resin film and has a circumferential surface portion (17) substantially maintained in contact with an inner surface (16) of syringe barrel (11). Gasket 13 also has an annular projection (22), provided on circumferential surface portion (17), extending circumferentially of circumferential surface portion (17). Projection (22) has a contact surface portion maintained in contact with inner surface (16) of syringe barrel (11) and having a width of 30 μm to 40 μm. Circumferential surface portion (17) has non-contact surface portions located out of contact with inner surface (16) of syringe barrel (11) on widthwise opposite sides of projection (22) and having a width of at least 30 μm.