| 摘要 |
A seal and method of manufacture is provided for sealing containers such as bottles, jars and the like. The seal (i.e., closure) (300) is formed with a lower sheet-like structure (301) having a non-foam, heat-distributing layer (330) thereon. The lower structure includes a foil support layer and has a polymer layer (320), such as a PET layer disposed on its bottom surface. A heat-activated sealant layer (340) is provided under the bottom surface of the PET layer to bond the seal to a container opening. The non-foam, heat-distributing layer is preferably a polyolefin film. Seals in accordance with preferred embodiments of the invention also include a top portion (302), which is only partially bonded (directly or indirectly) to the bottom portion, so as to leave a tab portion (303) extending from the seal. The top portion is advantageously bonded from periphery to periphery of the bottom portion and at or slightly offset from the diameter (middle) of the bottom portion. The top portion is advantageously formed with polymer material, such as an ethylene vinyl acetate (EVA) layer (360), having a layer (350) of PET bonded on the top thereof. A release strip (370), which can have a release layer (371) coated on the bottom thereof, is adhered to the top or bottom structures and used to prevent the tab from adhering to the lower structure. |
