SYRINGE, ITS SEALING STRUCTURE AND SEALING METHOD AND SLIDING VALVE FOR SYRINGE

摘要

A waterproof film (11) for covering fitting portions is closely formed on surfaces of a cap (6), barrel (3) and a cylinder body (2) to serve as a sealing construction for a syringe. The film is made of a synthetic resin having a higher fusing point than a temperature of steam which passes at the time of after-sterilization. A substantially wave-shaped inclined lip (24) is continuously formed on and projected from an outer periphery of a short-column shaped elastic body (22) to serve as slide valves for a syringe. An annular lip (23) is formed on an end of the body. A notch (34) for introduction of chemicals is formed on the inclined lip. The inclined lip is constructed such that substantially diverging lips are formed in pairs or in multi-stage or in axial ridges or intersecting one another in a corrugated manner. These slide valves are inserted and mounted without inclination to eliminate accumulation of air inside. In the syringe, an enlarged diameter portion (87) having a larger diameter than that of a cylinder is formed integrally on a tip end side of the cylinder such that it has a larger inner diameter than outer diameters of the slide valves to permit a chemical to be discharged through a gap around the outer periphery. A support projection (94) for the slide valves is formed at a bottom wall of the enlarged diameter portion to provide a bottom gap. A slide valve (90) comprises a body (101) having a smaller diameter than an inner diameter of the enlarged diameter portion, and a support member (102) having a lower elastic modulus than that of the body and a plurality of circumferentially equidistantly distributed support projections which project diametrically from inside of the body and contact with an inner surface of the enlarged diameter portion. The cylinder is of unitary-type, so that passing steam, bacteria and the like are prevented from entering the syringe.