| 摘要 |
PROBLEM TO BE SOLVED: To improve the liquid-tightness during the sliding of a gasket or the cooling in a high pressure steam sterilizing process by pressing a point of the gasket to a point surface of a plunger by adding the internal pressure of a hollow barrel to an outer surface of the gasket point part, and further radially pressing an inner surface of the hollow barrel by the point part. SOLUTION: This syringe 1 keeps the liquid-tightness by pressing an inner surface of a hollow barrel 2 by a point rib 15 and a basic rib of a gasket 3 during a high pressure steam sterilizing process in the manufacturing. In a cooling stage of the high pressure steam sterilizing process, an outside air temperature is lowered faster than the liquid medicine in the hollow barrel 2, as a result, the internal pressure is produced in the hollow barrel 2. By this internal pressure, the liquid-tightness at the point rib 15 and the basic rib is needed more, on the other hand, as the high pressure steam sterilizing process is in a stage with a temperature lowered to some degree, which dissipates the fear on thermal deformation of the inner surface of the resin hollow barrel 2. In the cooling stage, a point part 7 of the gasket 3 is pressed by the internal pressure in the hollow barrel 2, which enlarges a diameter of the point rib 15, and the sufficient liquid-tightness can be kept to the inner surface of the hollow barrel 2. |
