| 摘要 |
PROBLEM TO BE SOLVED: To provide a cap for liquid storage containers which is provided with an upper lid connected through a hinge, in addition to a spike for opening the container, and has excellent reliability.SOLUTION: With a polypropylene resin as a raw material, a cap 11 is produced as follows. A body part 12 fitting over a neck part 42 of a container 41, a top plate 13 covering the upper surface of the body part 12, an upper lid 14 covering the upper surface of the top plate 13, a hinge 15 connecting the upper lid 14 to the body part 12 and an elastic band 16 applying a biasing force to the upper lid 14 are molded in an integrated manner. A spike 31 to break through the container 41 is engaged in the lower surface of the top plate 13; a flange 33 is formed in the side peripheral surface of the spike 31; an annular wall 26 containing the flange 33 is formed on the lower surface of the top plate 13; and two or more ribs 27 pressing the outer edge of the flange 33 are formed on the inner peripheral surface of the annular wall 26. The structure causes the spike 31 to pierce the center of the neck part 42, even when the outside diameter of the flange 33 and the inside diameter of the annular wall 26 is not controlled strictly, ensuring completion of an opening operation. |
