| 摘要 |
<p>A plastic cap for vacuum sealing glass containers such as bottles or jars is disclosed. The cap includes a top wall and a depending annular side wall which extends over and is adapted to be threadedly secured to the neck of a container. The depending side wall has at its lower edge a lead-in chamfer and suitable threads adapted to engage corresponding threads formed on the exterior of the container to which it is to be secured. In a preferred form, serrations are provided on the exterior surface of the cap for gripping purposes, and a reinforcement shoulder is located on the outer perimeter of the side wall adjacent the lower edge thereof to prevent excessive cap expansion upon application to a container. Vacuum sealing is attained by means of two annular flanges depending from and integrally formed with the top wall of the cap. The two flanges are so located and angled as to engage the inner and outer rim edges of the container to which the cap is applied, whereby the flanges form air-tight seals with the rim edges when the cap is screwed onto the container.</p> |
