Closure with Integral Gas Barrier

Abstract

A cap ( 2 ) suitable for use with a PET beverage bottle has an integral gas barrier provided by a plastics-coated aluminium foil disc ( 30 ) having its peripheral edge ( 32 ) embedded into the plastics internal or external surface ( 40 ) of a top panel ( 4 ) of the cap or of a valve ( 20 ). A plastics component ( 28 ) from which the cap ( 2 ) can be produced is described. The component ( 28 ) has a recess ( 48 ) defined by a sacrificial wall ( 50 ) formed inwardly of a resealing valve ( 20 ).

1 - 27 . (canceled)  
   
   
       28 . A method of producing a cap ( 2 ) from an existing plastics component ( 28 ), comprising a top panel ( 4 ) surrounded by a skirt ( 6 ), and a plastics coated aluminium gas barrier foil ( 30 ), the method comprising the steps of placing the barrier foil ( 30 ) adjacent the top panel ( 4 ) and induction heat welding the foil to the panel ( 4 ) by melting the component indirectly by contact with the heated foil.  
   
   
       29 . A reclosable plastics cap ( 2 ) having a top panel ( 4 ), a skirt ( 6 ), a gas barrier ( 30 ) to inhibit gas flow through the cap ( 2 ), and a closed plug ( 92 ) substantially filling a void inside the cap to define a valve ( 20 ) adapted to fit inside and seal against an inner wall of a neck of a container to which the cap is fitted, characterised in that the cap can be resealed and in that the gas barrier is provided by means of a plastics coated aluminium foil ( 30 ) induction heat sealed to plastics material of the cap.  
   
   
       30 . A reclosable plastics cap ( 2 ) having a top panel ( 4 ) and a skirt ( 6 ), wherein a plastics coated aluminium foil liner ( 30 ) has a peripheral edge ( 32 ) that is embedded and fused into an external surface ( 70 ) of the skirt ( 6 ) or top panel ( 4 ) of the cap ( 2 ).  
   
   
       31 . A cap ( 2 ) as claimed in  claim 30 , wherein an opening ( 66 ) is formed in the top panel ( 4 ).  
   
   
       32 . A cap ( 2 ) as claimed in  claim 30 , wherein a valve ( 20 ), adapted to fit inside and seal against an inner wall of a neck of a container to which the cap is fitted, depends from the top panel ( 4 ).  
   
   
       33 . A cap ( 2 ) as claimed in  claim 32 , wherein the valve ( 20 ) is provided on a plate ( 62 ), which traps the foil liner ( 30 ) to an internal surface of the top panel ( 4 ).  
   
   
       34 . A cap ( 2 ) as claimed in  claim 33 , wherein the plate ( 62 ) has an opening ( 68 ) which cooperates with a corresponding opening ( 66 ) in the top panel to enable the foil to be pierced to access the contents of a container closed by the cap in use.  
   
   
       35 . A cap ( 2 ) as claimed in  claim 29 , wherein the foil liner ( 30 ) forms or covers an internal or external end face of the plug ( 92 ).  
   
   
       36 . A cap ( 2 ) as claimed in  claim 29 , wherein an interior of the plug ( 92 ) is defined by a recess ( 90 ) lined with the foil liner ( 30 ).  
   
   
       37 . A cap ( 2 ) as claimed in  claim 29 , wherein an interior of the plug ( 92 ) is lined with EVOH or other similar gas barrier plastics material.  
   
   
       38 . A cap ( 2 ) as claimed in  claim 29 , wherein the plastics coated aluminium foil ( 30 ) extends across the entire width of the valve ( 20 ).  
   
   
       39 . A cap ( 2 ) as claimed in  claim 38 , wherein the aluminium foil also extends up or down the wall of the valve ( 20 ).  
   
   
       40 . An assembly of a cap as claimed in  claim 29  and a glass, plastics, steel or aluminium bottle, jar or any other container.  
   
   
       41 . An assembly of a cap as claimed in  claim 29  and a container made of paperboard or composite material.  
   
   
       42 . An assembly of a cap as claimed as claimed in  claim 29  and a thermoformed container.  
   
   
       43 . A method of producing a cap ( 2 ) from a plastics component ( 28 ) comprising a top panel ( 4 ) surrounded by a skirt ( 6 ), a receiving recess ( 48 ) for a barrier foil, and a sacrificial wall ( 50 ), the method comprising the steps of placing a barrier foil ( 30 ) into the recess ( 48 ) and heating the wall ( 50 ) to melt the plastic material of the wall in order to embed an edge ( 32 ) of the foil ( 30 ) into the cap ( 2 ).  
   
   
       44 . A method as claimed in  claim 43 , wherein the heating step comprises induction heating the foil ( 30 ) to melt the wall ( 50 ).  
   
   
       45 . A method as claimed in  claim 43 , wherein the foil ( 30 ) is oversized and when placed into the recess ( 48 ) has its peripheral edge ( 32 ) pressed against an inner surface of the recess ( 48 ).  
   
   
       46 . A plastics component ( 28 ) for use in manufacturing a cap ( 2 ) by method as claimed in claim  1  or  16 , wherein an annular wall ( 20 ,  50 ) extends from the top panel ( 4 ) in order to define a recess ( 48 ) to receive the foil liner ( 30 ) wherein the wall ( 20 ,  50 ) has an intermediate, reduced cross-section portion ( 56 ) in order to enable a lower part ( 54 ) of the wall to be folded back towards the top panel in order to retain the peripheral edge ( 32 ) of the foil liner during production.  
   
   
       47 . A cap ( 2 ) as claimed in  claim 32 , wherein the plastics coated aluminium foil ( 30 ) extends across the entire width of the valve ( 20 ).  
   
   
       48 . A cap ( 2 ) as claimed in  claim 47 , wherein the aluminium foil also extends up or down the wall of the valve ( 20 ).  
   
   
       49 . An assembly of a cap as claimed in  claim 30  and a glass, plastics, steel or aluminium bottle, jar or any other container.  
   
   
       50 . An assembly of a cap as claimed in  claim 30  and a container made of paperboard or composite material.  
   
   
       51 . An assembly of a cap as claimed as claimed in  claim 30  and a thermoformed container.  
   
   
       52 . A method as claimed in  claim 44 , wherein the foil ( 30 ) is oversized and when placed into the recess ( 48 ) has its peripheral edge ( 32 ) pressed against an inner surface of the recess ( 48 ).