Plug seals for user-friendly cap assemblies

Abstract

A container closure assembly includes: a container neck having side walls defining an opening at one end thereof and a lip extending around the opening; a closure for the neck, the closure having a base portion and a threaded skirt portion; a first screw thread on the neck; a second screw thread on an inner surface of the threaded skirt of the closure; said first and second screw threads being configured to enable a user to secure, remove and resecure the closure into a sealing position on the neck by rotation of the cap on the neck; a sealing plug extending from the base portion of the closure inside and substantially concentric with the skirt portion of the closure, wherein the sealing plug includes one or more circumferential sealing ribs on an outer surface of said sealing plug for engagement with an inner surface of the container neck proximate to said lip when the closure is secured on the container neck; a sealing skirt extending from the base portion of the closure intermediate to the sealing plug and the threaded skirt portion of the closure and substantially concentric with the sealing plug and the threaded skirt portion of the closure; and one circumferential sealing rib on an inner surface of the sealing plug for engagement with an outer surface of the container neck proximate to said lip when the closure is secured on the container neck.

1 . A container closure assembly comprising: 
 a container neck having side walls defining an opening at one end thereof and a lip extending around the opening;    a closure for said neck, the closure having a base portion and a threaded skirt portion;    a first screw thread on the neck;    a second screw thread on an inner surface of the threaded skirt of the closure;    said first and second screw threads being configured to enable a user to secure, remove and resecure the closure into a sealing position on the neck by rotation of the cap on the neck;    a sealing plug extending from said base portion of the closure inside and substantially concentric with said threaded skirt portion of the closure, wherein the sealing plug comprises one or more circumferential sealing ribs on an outer surface of said sealing plug for engagement with an inner surface of the container neck proximate to said lip when the closure is secured on the container neck; and    a sealing skirt extending from said base portion of the closure intermediate said sealing plug and said threaded skirt portion of the closure and substantially concentric with said sealing plug and said threaded skirt portion of the closure, wherein the sealing skirt comprises one or more circumferential sealing ribs on an inner surface of said sealing plug for engagement with an outer surface of the container neck proximate to said lip when the closure is secured on the container neck;    wherein in use a first one of said sealing ribs on the sealing plug is located substantially the same longitudinal distance from the base portion of the closure as a first one of the circumferential sealing ribs on the sealing skirt, whereby the lip of the container neck is pinched between the said first sealing ribs when the closure is in the secured position on the container neck.    
   
   
       2 . A container closure assembly according to  claim 1 , wherein at least one of the sealing ribs has a substantially triangular cross-section.  
   
   
       3 . A container closure assembly according to  claim 1 , wherein the sealing ribs has a height in the range of 10 to 250 micrometers.  
   
   
       4 . A container closure assembly according to  claim 1 , comprising a plurality of said circumferential sealing ribs on said outer surface of said sealing plug  
   
   
       5 . A container closure assembly according to  claim 4  wherein the sealing rib furthest from the base of the closure has a greater height than the sealing rib closest to the base of the closure.  
   
   
       6 . A container closure assembly according to  claim 1 , further comprising at least one flexible sealing fin located between the sealing plug and the sealing skirt for engagement with the lip of the container when the closure is secured on the container neck.  
   
   
       7 . A container closure assembly according to  claim 6 , wherein at least one said sealing fin extends downwardly and outwardly from the base of the closure.  
   
   
       8 . A container closure assembly according to  claim 7 , further comprising a second sealing fin extending downwardly and inwardly from the base of the closure between the sealing rings.  
   
   
       9 . A container closure assembly according to  claim 7 , wherein at least one said sealing fin has a height of from 1 to 4 mm.  
   
   
       10 . A container closure assembly according to  claim 8 , wherein the sealing plug and the sealing skirt comprise at least one stop surface proximate to the base of the closure, whereby at least one sealing fin abuts against the stop surface when the closure is secured on the container neck.  
   
   
       11 . A container closure assembly according to  claim 1 , wherein respective lower ends of the sealing skirt and the sealing plug distal from the base of the closure are profiled to provide a jaw having a vertex on each of the sealing skirt and the sealing plug for gripping the neck of the closure.  
   
   
       12 . A container closure assembly according to  claim 1 , wherein the container lip is semi-circular.  
   
   
       13 . A container closure assembly according to  claim 1 , wherein the closure can be secured and resecured on the container neck by a single smooth rotation through 360° or less, preferably through 180° or less, and more preferably through about 90°.  
   
   
       14 . A container closure assembly according to  claim 1 , wherein the first and second threads are multiple start threads.  
   
   
       15 . A container closure assembly according to  claim 1 , wherein the first and second threads are substantially continuous helical threads.  
   
   
       16 . A container closure assembly according to  claim 1 , wherein the container and closure further comprise complementary locking elements on the container neck and the closure that block or resist unscrewing of the closure from the fully secured position on the container neck until a predetermined minimum opening torque is applied.  
   
   
       17 . A container closure assembly according to  claim 1 , further comprising a projecting stop surface on one of the container neck and the closure skirt for abutment against a second stop or a thread on the other of the container neck or the closure to block over-tightening of the closure beyond a predetermined angular sealing position of the closure on the container neck.  
   
   
       18 . A container closure assembly according to  claim 1 , wherein the torque required to secure the closure in a sealing position on the container neck is from about 0.7 Nm to about 0.9 Nm.  
   
   
       19 . A container closure assembly according to  claim 1 , wherein the assembly achieves a sealing pressure around at least one circumferential surface between the container neck and the closure at the fully closed position of at least about 7 MPa (1000 psi).  
   
   
       20 . A container closure assembly according to  claim 19 , wherein the assembly provides at least two such circumferential seals between the container neck and the closure at the fully closed position.  
   
   
       21 . A container closure assembly according to  claim 1 , wherein an inner surface of the side wall of the container neck proximate to said lip is inwardly tapered.  
   
   
       22 . A beverage container comprising a container closure assembly according to  claim 1 .  
   
   
       23 . A beverage container according to  claim 22  which is a carbonated beverage container.  
   
   
       24 . A container closure assembly comprising: 
 a container neck having side walls defining an opening at one end thereof and a lip extending around the opening;    a closure for said neck, the closure having a base portion and a threaded skirt portion;    a first screw thread on the neck;    a second screw thread on an inner surface of the threaded skirt of the closure;    said first and second screw threads being configured to enable a user to secure, remove and resecure the closure into a sealing position on the neck by rotation of the cap on the neck;    a sealing plug extending from said base portion of the closure inside and substantially concentric with said threaded skirt portion of the closure, wherein the sealing plug comprises one or more circumferential sealing ribs on an outer surface of said sealing plug for engagement with an inner surface of the container neck when the closure is secured on the container neck;    a sealing skirt extending from said base portion of the closure intermediate said sealing plug and said threaded skirt portion of the closure and substantially concentric with said sealing plug and said threaded skirt portion of the closure, wherein the sealing skirt comprises one or more circumferential sealing ribs on an inner surface of said sealing plug for engagement with an outer surface of the container neck when the closure is secured on the container neck.