| 摘要 |
<p>The tube has the mouth of its neck sealed by a membrane. A cap with a central boss to pierce the membrane screws onto the neck. The neck extends beyond the threaded portion (5) at the end towards the tube for a distance (3) at least equal to the length of the boss (7). Between this part (3) and the threaded one is a ring (4) protruding outwards, against which an internal bead (8) in the cap (6) of smaller dia. than the ring bears.</p> |
