Laminated Container Seal With Removal Tab Bound By Adhesive

Abstract

A sealing member for a container including a polyethylene or polypropylene foam or film layer bonded to a foil layer. A first PET tab defining layer over at least a first portion of, but is not bonded to the first portion of, the polyethylene or polypropylene foam or film layer. A polypropylene film layer bonded to both a second portion of the polyethylene or polypropylene foam or film layer not covered by the first PET tab defining layer and also to the first PET tab defining layer itself, the bonds being established by an adhesive resin and catalyst to provide a bonding strength sufficient to hold against a manually generated force. The sealing member also includes a second PET layer bonded to the polypropylene film layer.

1 . A sealing member for a container having a rim surrounding a container opening, the sealing member comprising:
 a heat actuated sealant or adhesive layer for securing the sealing member to the rim of a container;   a metal foil layer over the heat actuated sealant or adhesive layer;   a polyethylene or polypropylene foam or film layer bonded to the foil layer;   a first PET tab defining layer over at least a first portion of, but not bonded to the first portion of, the polyethylene or polypropylene foam or film layer to form a tab;   a polypropylene film layer bonded to both a second portion of the polyethylene or polypropylene foam or film layer not covered by the first PET tab defining layer and also to the first PET tab defining layer itself, the bonds being established by an adhesive resin and catalyst to provide a bonding strength between the polyethylene or polypropylene foam or film layer and the polypropylene film layer so that the entire sealing member may be removed from the container in one piece by pulling on the tab;   a second PET layer bonded to the polypropylene film layer; and   wherein the first PET tab defining layer and portions of the polypropylene film layer immediately above and bonded to the first PET tab defining layer and portions of the second PET layer immediately above and bonded to the polypropylene film layer serve as the tab to facilitate removal of the sealing member from a container to which it has been adhered.   
     
     
         2 . A sealing member in accordance with  claim 1  wherein the polyethylene or polypropylene foam or film layer is polyethylene film. 
     
     
         3 . A sealing member in accordance with  claim 1  wherein the polyethylene or polypropylene foam or film layer is polyethylene foam. 
     
     
         4 . A sealing member in accordance with  claim 1  wherein the polypropylene film layer is a blown film in the range of 0.002 to 0.006 inches thick. 
     
     
         5 . A sealing member in accordance with  claim 1  wherein the polyethylene or polypropylene foam or film layer is 0.002 to 0.006 inches thick. 
     
     
         6 . A sealing member in accordance with  claim 1  wherein the polypropylene film layer and the polyethylene or polypropylene foam or film layer are more than twice the thickness of any of the PET layers. 
     
     
         7 . A sealing member in accordance with  claim 1  wherein a third PET layer lies between the heat activated sealant or adhesive layer and the metal foil layer. 
     
     
         8 . A sealing member for a container having a rim surrounding a container opening, the sealing member comprising:
 a hot melt bonding material or adhesive layer that, when heated, can secure the sealing member to the rim of the container, forming a seal to the container rim;   a sealing layer bonded to the hot melt bonding material or adhesive layer, the sealing layer comprising a metal foil layer;   a polyethylene or polypropylene foam or film layer, having a melting point near to or above 125 degrees Celsius and sufficiently thick to prevent heat from damaging the sealing member elements above this layer, bonded to the foil layer;   a first PET tab defining layer extending over and covering at least a first portion of, but not bonded to the first portion of, the polyethylene or polypropylene foam or film layer;   a polypropylene film layer bonded to a second portion of the polyethylene or polypropylene foam or film layer not covered by the first PET tab defining layer and also bonded to the first PET tab defining layer itself by a two-part urethane adhesive resin and catalyst having a bonding strength near to or above 3500 g/in;   a second PET upper layer bonded to the polypropylene film layer; and   wherein the first PET tab defining layer and portions of the polypropylene film layer immediately above and bonded to the first PET tab defining layer and the second PET upper layer immediately above and bonded to the polypropylene film layer together form a removal tab that facilitates removal of the sealing member from a container to which it has been adhered by inductive heating.   
     
     
         9 . A sealing member in accordance with  claim 8  wherein the polyethylene or polypropylene foam or film layer is polyethylene film. 
     
     
         10 . A sealing member in accordance with  claim 8  wherein the polyethylene or polypropylene foam or film layer is polyethylene foam. 
     
     
         11 . A sealing member in accordance with  claim 8  wherein the polyethylene or polypropylene foam or film layer is polypropylene film. 
     
     
         12 . A sealing member in accordance with  claim 8  wherein the polyethylene or polypropylene foam or film layer is polypropylene foam. 
     
     
         13 . A sealing member in accordance with  claim 8  wherein the polyethylene or polypropylene foam or film layer is a co-extruded film comprised of both polyethylene and polypropylene. 
     
     
         14 . A sealing member in accordance with  claim 8  wherein the polyethylene or polypropylene foam or film layer is a blend comprising approximately 70% HDPE blended with MDPE. 
     
     
         15 . A sealing member in accordance with  claim 8  wherein the polyethylene or polypropylene film or foam layer is a blown film in the range of 0.002 to 0.006 inches thick. 
     
     
         16 . A sealing member in accordance with  claim 8  wherein the polyethylene or polypropylene film or foam layer is a foam layer in the range of 0.003 to 0.009 inches thick. 
     
     
         17 . A sealing member in accordance with  claim 8  wherein the polypropylene film layer is a polypropylene blown film in the range of 0.002 to 0.006 inches thick. 
     
     
         18 . A sealing member in accordance with  claim 8  wherein the polypropylene film layer is a co-extruded film comprising HDPE and polypropylene. 
     
     
         19 . A sealing member in accordance with  claim 8  wherein the adhesive resin and catalyst that bonds the polypropylene film layer to the second portion of the polyethylene or polypropylene foam or film layer not covered by the first PET tab defining layer and also to the first PET tab defining layer has a bonding strength near to or above 4000 g/in. 
     
     
         20 . A sealing member in accordance with  claim 8  wherein the sealing layer further comprises a PET layer between the metal foil layer and the hot melt bonding material or adhesive layer.