| 摘要 |
An injector having an excellent air-tightness and capable of being sufficiently sterilized with a plunger rod, which has a flange, mounted in the injector. The air-tightness is achieved by a back-stop function of the flange located at a position separated from a gasket toward the base end side. A gasket (3) is inserted into a barrel (2) from a base end opening (22) of the barrel (2), a plunger rod (4) is inserted into the barrel (2) to connect the front end of the plunger rod to the gasket (3), and a finger grip (5) is mounted to a flange (23). A disc section (45) is formed at that portion of the plunger rod which is separated from the gasket toward the base end side, and this enables the disc section to make contact with a hole edge (521) of the finger grip. A recessed communication opening (451) is formed in the outer peripheral edge of the disc section (45). In sterilization using hydrogen peroxide gas, the hydrogen peroxide gas entering an open space (26) from the base end opening can also flow into a substantially closed space (25) through the communication opening. |
