Patent ID: 8080118
Filing Date: 2011-12-20
Classification: B29C,B29L,B32B,B65D,Y10T

Abstract:
1. A method of manufacturing a two-piece container seal suitable for sealing a container having a removable closure and for lining said closure, the method comprising: contacting a first thermoplastic surface of a moving web of a first flexible sheet material with a second thermoplastic surface of a moving web of a second flexible sheet material, the webs of the first and second flexible sheet materials moving at substantially the same speed and in the same direction; ultrasonically forming at least one array of spaced, frangible ultrasonic welds between the first and second thermoplastic surfaces, thereby producing a flexible multilayer sheet material comprising a first outer surface from the first flexible sheet material, a second outer surface from the second flexible sheet material, and an adhesive-free interface between the first and second thermoplastic surfaces of the first and second flexible sheet materials; and cutting a container seal from the multilayer sheet material; wherein, when the first outer surface of the container seal is bound over a container finish as a seal and the second outer surface is bound to a closure engaged with the container finish, the first flexible sheet material separates from the second flexible sheet material by shearing of the frangible ultrasonic welds when the closure is removed from the container finish, thereby leaving the first flexible sheet material on the container finish as a seal and leaving the second flexible sheet material as a liner in the closure.