| 摘要 |
Conventional adhesive and contact welding methods for holding the paperboard and plastic components of a composite closure together present a number disadvantages and do not lend themselves easily to mass production. The present invention describes two novel approaches, firstly the pre-assembly heating of the closure components with directed hot air to partially melt the thermoplastic surfaces and allow the parts to be immediately assembled sealingly and, secondly, a novel construction of plastic and paperboard composite closure in which the plastic rim is of a two-piece snap-fit constructions which firmly grips the top panel of the paperboard lid. |
