| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a cap capable of obtaining sufficient sealability when the cap is not unsealed, and preventing excessive increase of internal pressure in a container when the cap is re-sealed after the cap is unsealed. <P>SOLUTION: The cap comprises a cap body 4 having a top plate portion 2 and a cylindrical portion 3, and a packing 5 provided in the cap body 4. The packing 5 has a bottom plate portion 12 and a cylindrical portion 13 extending upwardly from a circumferential edge 12a thereof. A maximum outside diameter portion 18 of the cylindrical portion 13 is abutted on an inner surface 21a of the container. When the internal pressure of the container 20 is increased, the bottom plate portion 12 is swollen upwardly and deformed by the internal pressure of the container. When the bottom plate portion 12 is swollen and deformed, at least a part of the maximum outside diameter portion 18 of the cylindrical portion 13 is separated from the inner surface 21a of the container. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
