Composite closure with enhanced sealing

Abstract

A composite closure includes a plastic outer closure cap, and an inner sealing liner positioned adjacent to an inside surface of a top wall portion of the outer cap. In order to enhance sealing integrity with an associated container, the liner is configured to include inward and outwardly facing sealing surfaces, with the provision of an annular sealing bead providing a top/side seal with an associated container, and an annular sealing plug fitting within the mouth of an associated container for providing an inside seal. The closure construction has been found to maintain sealing integrity with an associated container when the closure and container package is subjected to relatively high temperatures.

What is claimed is:  
     
         1 . A composite closure for a container, comprising: 
 an outer closure cap having a top wall portion and an annular skirt portion, said closure cap including an annular shoulder extending inwardly of said skirt portion in spaced relationship to said top wall portion; and    a sealing liner positioned adjacent an inside surface of said top wall portion,    said sealing liner including an annular outside sealing portion positioned adjacent to said annular shoulder, and an annular inside sealing plug spaced inwardly from said outside sealing portion, and defining therewith an annular recess for receiving said container,    said outside sealing portion including an outwardly, downwardly tapering guide surface adjacent said shoulder, and an outside sealing surface extending from said guide surface into said annular recess, and a transition region extending therebetween    said sealing plug including an inwardly, downwardly tapering guide surface, an adjacent inside sealing surface extending into said annular recess,    said guide surfaces facilitating fitment of said closure to a container and disposition of said container in said annular recess between said outside and inside sealing surfaces.    
     
     
         2 . An composite closure in accordance with  claim 1 , wherein: 
 said guide surface and said sealing surface of said sealing plug are arranged at an obtuse angle to each other.    
     
     
         3 . A composite closure in accordance with  claim 2 , wherein: 
 said sealing surface of said sealing plug is vertically oriented.    
     
     
         4 . A composite closure in accordance with  claim 1 , wherein: 
 said sealing surfaces are arranged in converging relationship in said angular recess.    
     
     
         5 . A composite closure in accordance with  claim 3 , wherein: 
 said sealing liner includes a downwardly facing top sealing surface extending between the sealing surface of said outside sealing portion and the sealing surface of said sealing plug, said top sealing surface being perpendicular to said sealing surface of said plug.    
     
     
         6 . A composite closure in accordance with  claim 1 , wherein: 
 said outer closure cap defines an annular recess positioned between said annular shoulder and said top wall portion into which said annular sealing portion of said liner extends.    
     
     
         7 . A composite closure for a container, comprising: 
 an outer closure cap having a top wall portion and an annular skirt portion, said closure cap including an annular shoulder extending inwardly of said skirt portion in spaced relationship to said top wall portion; and    a disc-shaped sealing liner positioned adjacent to an inside surface of said top wall portion,    said sealing liner including an annular outside sealing bead portion positioned adjacent said annular shoulder, and an annular inside sealing plug spaced inwardly from said outside sealing bead portion, and defining therewith an annular recess for receiving said container,    said sealing bead portion including an outwardly, downwardly tapering guide surface adjacent said shoulder, and an outside sealing surface extending from said guide surface into said annular recess,    said plug including an inwardly, downwardly tapering guide surface and an adjacent inside sealing surface extending into said annular recess arranged vertically and at an obtuse angle to said plug sealing surface,    said sealing surfaces being arranged in converging relationship in said annular recess, and extending to a downwardly facing top sealing surface which is perpendicular to said vertical sealing surface of said sealing plug.    
     
     
         8 . A composite closure in accordance with  claim 7 , wherein: 
 said outer closure cap defines an annular recess positioned between said annular shoulder and said top wall portion into which said annular sealing bead portion of said liner extends.    
     
     
         9 . A composite closure in accordance with  claim 8 , wherein: 
 said sealing liner defines a radius between said sealing surface of said bead portion and said top sealing surfaces of at least about 0.005 inches.    
     
     
         10 . A composite closure in accordance with  claim 8 , wherein: 
 said sealing plug defines a radius between the guide and sealing surfaces thereof of at least about 0.010 inches.    
     
     
         11 . A composite closure in accordance with  claim 8 , wherein: 
 said guide surface of said sealing plug extends at an angle of 15°, ±10° relative to the horizontal.