| 摘要 |
PURPOSE: To provide a cap which is capable of keeping the hermetic condition during the heat treatment and sanitarily and easily openable in one action by positioning a container holding means along an inner surface so as to be cooperatively engaged with a plastic container, and holding an upper part so that an upper part holding means is cooperated with an inner surface of a side wall. CONSTITUTION: A heat-fusible metallic disk 40 is placed inside a cap 10, and the cap 10 is screwed to a neck part 13 of a container 12 filled with nutritious food. As an inclined inner surface 35 of the cap 10 is brought into mechanical contact with an outer part 45 of the metallic disk 40, the pressing-down force is applied to the metallic disk 40 through the inclined inner surface 35. The plastic container 12 is preferably formed of polypropylene, and when the cap 10 is exposed to the electromagnetic energy source to be generated by an induction coil like an electromagnetic flow, the particles of the metallic disk 40 are excited to melt a coated layer 42, and a lower surface 41 of the metallic disk 40 is melted and attached to an end face 16 of a spout of the container. When the fusion and attachment is once achieved, a hermetic seal is obtained, and the hermetic seal capable of withstanding the heat treatment up to 135 deg.C can be obtained. |
