Beverage container closures

Abstract

A container for a carbonated beverage has an interrupted external screw thread surrounding its mouth opening engageable with an internal screw thread of a rotatable closure. The rotatable closure is in two parts and has a stiffened top member and a separate, rotatable depending rim to rotatably engage on the container and hold the top member in sealing engagement with the opening of the container. To prevent missiling on opening, pressure venting means such as slots extending through the closure may be provided. Alternatively, the rotatable closure may be configured to have a two stage opening movement. As the rotatable closure is made in two parts it has a low opening torque.

Description

[0001] The present invention relates to the use of a rotatable closure to close a container for carbonated beverages, to a container for carbonated beverages, and to a rotatable closure for a carbonated beverage container.

[0002] British patent No. 2,254,594 discloses a container for beer and other beverages which is particularly suitable for dispensing carbonated beverages to a large number of people at a public venue. The container disclosed in the identified British patent is made of plastics material and has an unrestricted mouth opening such that the container itself can be used as the drinking vessel. The opening has an external screw thread proximate thereto and the proposal of British patent No. 2,254,594 is to provide a correspondingly threaded end closure.

[0003] There are currently large numbers of designs of closures for containers, including many designs of closures arranged to be affixed and removed from the corresponding container by a screw action. However, none of the readily available closures behave entirely satisfactorily with a container of the type disclosed in the above identified British patent.

[0004] The present invention seeks to provide closures which can be used satisfactorily with carbonated beverage containers.

[0005] According to a first aspect of the present invention, there is provided the use of a rotatable closure to close a container for carbonated beverages, wherein said rotatable closure comprises a top member and a separate rim, the rim being held on the top member and being rotatable relative to the top member, and wherein said container has a body member having an opening at one end thereof, and external engagement means formed on said body member proximate to said opening, wherein cooperable engagement means are formed internally of the rim of said rotatable closure, and wherein the container opening is closed by engaging the engagement means of said rim with the engagement means of the container.

[0006] The use of a rotatable closure of an embodiment of the invention, which has a separate, rotatable, rim ensures that the container can be reliably closed against the pressure of its contents, and yet be opened relatively easily. In this respect, to open the container it is only necessary to rotate the rim and not the top member of the closure. If the container has a wide mouth opening, the top member forms a large part of the closure. By this means, the opening torque of the closure is reduced quite considerably.

[0007] The container may be fabricated from any suitable material, for example, from metal or glass. In a preferred embodiment, the container is fabricated from plastics material.

[0008] Preferably, said opening defines an unrestricted mouth opening for the container. For example, the opening may have a diameter exceeding 30 mm, or 50 mm.

[0009] In an embodiment, said cooperable engagement means on said rim and on the container are arranged such that said rotatable closure is engageable and removable from the container by rotating the rim of the rotatable closure relative to the opening of the container.

[0010] As explained, the rotatable closure is removable from the container by rotation of the rim, and preferably, rotation of said rim through less than one complete revolution thereof is effective to enable removal of the closure.

[0011] In one embodiment, the cooperable engagement means comprises an external screw thread provided on said container around said opening. The screw thread on the container may be continuous or interrupted. The screw thread on the container may vary in pitch.

[0012] The cooperable engagement means on the interior of the rim of the closure, for cooperation with the screw thread, for example, on the container, may comprise a plurality of lugs and/or an internal screw thread.

[0013] In a preferred embodiment, a plurality of lugs are spaced around the opening of the container, and an internal screw thread is provided on the interior of the rim of the closure for cooperation with said lugs.

[0014] Preferably, to prevent missiling of the closure on opening, pressure venting means are associated with the closure. For example, said pressure venting means may comprise one or more slots extending through said closure, and/or through said container.

[0015] Additionally and/or alternatively, said pressure venting means comprise means associated with said cooperable engagement means for imparting a two stage opening movement to said rotatable closure relative to the opening of the container.

[0016] The present invention also extends to a container for carbonated beverages comprising a body member having an opening at one end thereof, and external engagement means formed on said body member proximate to said opening, and a rotatable closure engaged on said container to close the opening, the rotatable closure comprising a top member and a depending rim, and wherein cooperable engagement means are formed internally of the rim of said rotatable closure and engage the external engagement means to hold the rotatable closure on the container.

[0017] As previously, the body member may be of any suitable material, for example of glass or metal. However, for use at public venues it is preferred that the body member be fabricated of plastics material.

[0018] The rotatable closure defined above, and the rotatable closure incorporated in an embodiment of a container of the invention, may be fabricated, at least in part, of metal. Closures incorporating metal generally have a lower coefficient of friction than closures made entirely of plastics material and the use, therefore, of metal reduces the opening torque.

[0019] The rim of the rotatable closure may be made of any suitable material, for example, of plastics or of metal.

[0020] The top member of the rotatable closure is preferably suitably shaped to provide stiffness thereto.

[0021] In a preferred embodiment, the top member of the rotatable closure is deformed inwardly. This deformation provides the closure with a large surface area and thereby stiffens the closure and enables it to withstand the pressure of the carbonated contents of the container.

[0022] In a preferred embodiment, the inward deformation of the top member is utilised to form a seal between the closure and the container.

[0023] Preferably, the engagement between the rotatable closure and the container is arranged such that the closure may be removed by rotating it through less than one complete revolution thereof. This ensures quick and easy removal of the closure, a feature which is very important if the container is being used to dispense beverages at a public venue.

[0024] The container is also, preferably, provided with pressure venting means to prevent missiling of the closure. Preferably, the pressure venting means are associated with the closure. For example, slots may extend through the closure and/or the container. In one embodiment, these slots are adjacent to the engagement means of the closure.

[0025] Additionally and/or alternatively, means may be associated with the engagement means of the closure to impart a two stage opening movement thereto. For example, such means may be arranged to halt an opening movement of the closure relative to the container opening. For example, appropriate stops may be provided on the closure and/or on the container. As the closure is rotated to effect opening, part of the closure or of the container will abut against the stops. This arrest of the opening movement is designed to provide for pressure venting. The effect of the stops can be overcome by, for example, pressing down on the closure whereby the rest of the opening rotation is enabled.

[0026] In an embodiment, cooperable engagement means on said rim and on the container are arranged such that said rotatable closure is engageable and removable from the container by rotating the rotatable closure relative to the opening of the container. For example, said rotatable closure may be removable by rotating said closure relative to the periphery of the opening, and wherein rotation of said closure through less than one complete revolution thereof is effective to enable its removal.

[0027] Preferably, the cooperable engagement means comprises an external screw thread provided on said container around said opening. The screw thread on the container may be continuous or interrupted.

[0028] The cooperable engagement means on the interior of the rim of the closure, for cooperation with the screw thread, for example, on the container, may comprise a plurality of lugs and/or an internal screw thread.

[0029] In an alternative embodiment, the cooperable engagement means comprise an internal screw thread on the rim of said rotatable closure.

[0030] Said screw thread on the rim may be interrupted, and/or may vary in pitch.

[0031] In this embodiment, said cooperable engagement means further comprise a plurality of lugs provided on said container and spaced around said opening, said lugs being engageable with said internal screw thread.

[0032] The container as defined above may have any of the features of the use of the rotatable closure as defined above, and/or any of the features of the rotatable closure as defined below.

[0033] Similarly, the use of the rotatable closure as defined above may incorporate any of the features of the container as defined above, and/or any of the features of the rotatable closure as defined below.

[0034] The present invention also extends to a rotatable closure for a carbonated beverage container, said rotatable closure comprising a top member, and a peripheral rim depending relative to said top member, and wherein the top member is shaped to stiffen the closure.

[0035] In an embodiment, said peripheral rim is separate from the top member and is held on the top member to be rotatable around the periphery thereof.

[0036] The rotatable closure may be fabricated and configured as defined above.

[0037] Embodiments of the present invention will hereinafter be described, by way of example, with reference to the accompanying drawings, in which:

[0038] FIG. 1 shows schematically a carbonated beverage container with a closure therefor,

[0039] FIGS. 2a, 2b, and 2c show respectively the mouth opening of a container having engagement means in the form of a series of lugs, an extended view of the mouth opening, and an extended view of the internal surface of a closure cooperable therewith,

[0040] FIGS. 3a and 3b show schematically part of a thread provided on a rotatable closure and the lugs on the container mouth opening, and illustrate the closing and opening movements of the closure,

[0041] FIG. 4 shows a section through an embodiment of a rotatable closure, for use with a carbonated beverage container,

[0042] FIG. 5 shows a further rotatable closure of the type shown in FIG. 4,

[0043] FIG. 6 shows a still further embodiment of a rotatable closure of the type shown in FIG. 4, and

[0044] FIG. 7 shows an alternative embodiment of a rotatable closure of the type shown in FIG. 4,

[0045] FIG. 8 shows an embodiment of a rotatable closure of the present invention, wherein part of the rotatable closure is illustrated in position on the annular periphery of a mouth opening of the container.

[0046] FIG. 9 shows an interior plan view of a top member of the closure of FIG. 8, and

[0047] FIG. 10 shows an alternative embodiment of the closure and opening configuration as shown in FIG. 8.

[0048] The invention is described herein specifically with reference to a carbonated beverage container of plastics material as described, for example, in UK patent No. 2,254,594. However, whilst the present invention has been specifically designed for use with such a container, the invention is not limited to containers as described and claimed in the British patent. For example, a carbonated beverage container of the invention may be made of a plastics material, or of glass, or of metal, or of any other suitable material.

[0049] FIG. 1 shows an example of a beverage container of plastics material for use for dispensing beer or other carbonated beverages. In this respect, the container comprises of substantially cylindrical body member 2 of plastics material having a closed end 4 and a generally circular mouth opening 6 at the end thereof opposed to said closed end 4. An interrupted external screw thread 8 is provided on the body member 2 and surrounds, but is spaced from, the mouth opening 6.

[0050] The container of FIG. 1 is also provided with a closure 100 having an internal screw thread (not visible) arranged to engage the screw thread 8 of the container. Thus, when the body member 2 has been filled, the closure 100 can be engaged thereon by engaging the screw threads of the closure and of the body member and then rotating or screwing the closure to its closed position. When it is required to have access to the contents of the container, the closure 100 is removed and may be discarded.

[0051] The construction and configuration of the closure 100, and the method of its engagement on the container, has to be chosen with care to meet a number of desired criteria. It is, of course, required that the closure 100 is able to withstand the pressure of the contents of the container when the container has been filled with a carbonated beverage. However, it is also generally required that the closure can be removed quickly. Where the closure is engaged by rotation or by screw action, the requirement for easy and speedy access generally means that the closure should not have to be rotated more than one complete revolution in order to release it. However, in general, the smaller the amount of revolution required to remove the closure, the greater the danger that the closure will be missiled off due to the pressure of the container contents.

[0052] Similarly, it is required that there be a seal between the closure and the container when the container is closed in order to keep the beverage pressurised. However, the greater and more effective the seal, the greater the risk that the required opening torque will be unacceptably large.

[0053] FIG. 4 illustrates an embodiment of a two-part rotatable closure 100 for use with a container as indicated in FIG. 1. The closure 100 comprises a top member 102, for example, made of a metal, which is generally in the form of a circular disc but has an annular channel 104 provided therein. Furthermore, the top member 102 is also formed to have a radially extending flange 106. The top member 102 carries a depending peripheral rim 108 which has two axially spaced, radially extending flanges 110 and 112 engageable with the flange 106 of the top member to hold the rim 108 relative to the top member 102. On the internal annular surface of the rim 108, engagement means, such as a screw thread 120, are provided. The rim 108 is held on the top member 102 to be freely rotatable relative thereto.

[0054] The engagement means may comprise a plurality of lugs arranged to engage with the screw thread 8 on the body member 2 of the container. Where the screw thread 8 is interrupted, for example as shown in FIG. 1, the lugs on the closure may be spaced apart by a distance substantially the same as the length of each length of the screw thread 8. With this arrangement, the rotatable closure 100 of FIG. 4 may be engaged with the body member by a screw action which is effective to position each lug beneath a length of the screw thread 8. Removal of the closure 100 is effected by a reverse screw action.

[0055] The top member 102 of the closure is shaped to provide stiffness to the construction and, therefore, to provide the ability for the closure 100 to withstand the pressure within the beverage container. In this respect, the top member 102 may have any suitable shape which imparts the necessary stiffness. For example, a double curve may be imposed on the top member and/or a star shape may be impressed therein. Frequently, shapes in which the top member 102 is inwardly deformed will be used as such shapes facilitate the incorporation of sealing means as described further below.

[0056] The embodiments described so far show the use of an interrupted screw thread on the body member 2 of the container for engagement with a screw thread or with lugs provided on an inner surface of a rim of the closure. However, it will be appreciated, that any cooperable engagement means, which enable the closure to be reliably engaged on the container, and enable removal of the closure by a twisting action may be utilised. For example, threads may be provided on the body member or on the closure and such threads may be continuous or interrupted. The other of the closure and the body member may be provided with cooperating threads, with lugs, recesses, guides, or other formations.

[0057] However, there is an advantage to utilising a screw thread on one of the container and the closure, and lugs on the other of the closure or container, as such an arrangement enables pressure venting for the closure to be provided.

[0058] In this respect, FIG. 2a shows part of the body member 2 of a is container having a plurality of lugs 30 provided externally of the body member 2 and around the mouth opening 6. FIG. 2b shows an extended view of the neck showing the lugs 30, whereas FIG. 2c shows an extended view of the inner cooperating surface of a depending peripheral rim of a closure, as 100, which is provided with an interrupted screw thread 40. This closure 100 is to be used with the body member 2 of FIG. 2a.

[0059] FIGS. 3a and 3b show adjacent sections or lengths of the interrupted screw thread 40 provided on the inner surface of the rim of the closure 100. As can be seen, the lengths of the screw thread 40 are shaped to guide the lugs 30 during opening and closing, and at one end, each length of the screw thread 40 has an angle flat section 42 and at its other end, each length of screw thread 40 has a further flat 44 terminated in a stop 46. A lug 30 of the body member 2 of the container will lie on a respective angle flat 42 in the closed condition of the closure.

[0060] When the closure 100 is to be opened, its depending peripheral rim 108 is rotated relative to the mouth opening 6 whereby each lug 30 is moved along the corresponding length of the screw thread 40 until the lug 30 is received in the position 30′. In that position, the stop 46 prevents further relative rotation between the closure rim and the container. However, if the closure is then pressed downwardly, the lug 30 is positioned above the stop 46, and further rotation of the closure rim, and hence removal of the closure, can be achieved. This two stage opening of the closure allows pressure to be vented whilst the closure and the container are still engaged. Thus, the stops 46 are effective as anti-missiling stops.

[0061] It will be appreciated that in the arrangement shown in FIGS. 3a and 3b, the lengths of screw thread 40 are shaped to have a variable pitch. By this means, the removal of the closure from the body member employs a camming action derived from the variation in pitch. Of course, alternative constructions can be provided.

[0062] The particular screw thread and lug configuration illustrated is arranged to enable removal of the closure upon rotation thereof through less than one complete revolution. Preferably, removal is arranged to occur after about one quarter of one revolution of the closure.

[0063] As is illustrated in FIG. 4, when the closure 100 is in position closing a container, the periphery of the container's mouth opening, as 6, is received within the annular channel 104 as earlier described. In this respect, and as indicated in FIG. 4, a sealing compound 122 may be received within the channel 104. The sealing of the container in the closed position of the closure 100 can thereby be ensured.

[0064] Alternative sealing means, such as a rubber ring (not shown), may be housed within the channel 104.

[0065] To open a container closed by the closure 100, the rim 108 is grasped, in normal manner, and is rotated relative to the container. However, whereas with a conventional one part closure the whole of the closure has to be rotated, opening of the container utilising a closure as 100 can be achieved by rotation of the rim 108 only whereby the opening torque is considerably reduced.

[0066] The closure 100 shown in FIG. 4 may additionally and/or alternatively be provided with pressure venting means, for example, in the form of slots (not shown) extending through the rim 108 from its inner to its outer surface. Such slots, for example, may extend upwardly from an opening in the inner surface of the rim 108 and exit in the flange 110. When the rim 108 is rotated to open the container, the action of the screw thread 120 on the corresponding thread or lugs of the container lifts the closure and may be sufficient to partially or fully break any seal between the closure and the container. This enables pressure from the interior of the container to be vented by way of the vent slots in the closure. Continued rotation of the rim 108 then effects removal of the closure 100.

[0067] Of course, the pressure venting slots may be incorporated in any suitable area of the closure and/or container. For example, pressure venting slots may extend through the screw thread 120 of the closure, and/or through the corresponding screw thread or other engagement means of the container.

[0068] The rim 108 of the closure may be made of any suitable material. For example, the rim 108 may be made of a plastics material. Alternatively, the rim 108 may be made of metal, for example, it may be a spun or pressed metal threaded band.

[0069] FIG. 5 shows schematically an alternative embodiment of the closure 100 in which the top member 102 is inwardly deformed. In the embodiment shown in FIG. 5, the top member 102 is inwardly indented. FIG. 6 shows an alternative embodiment in which the top member 102 is inwardly domed. In both of the embodiments of FIGS. 5 and 6, the inward deformation of the top member 102 increases the surface area of the top member and hence increases the stiffness of the closure and its ability to withstand pressure as described earlier.

[0070] FIG. 7 shows a still further embodiment of the closure 100 in which the radially extending flange 110 of the rim 108 extends over the top member 102. In the embodiment illustrated in FIG. 7, the periphery of the mouth opening of a container 160 is shown received within the annular channel 104 of the closure 100.

[0071] FIGS. 8 and 9 show an embodiment of a rotatable closure 200 of the present invention. Specifically, FIG. 8 shows part only of the closure 200 engaging on the annular periphery of the mouth opening 6 of a container as 2 to close the mouth opening.

[0072] As previously, the rotatable closure 200 is a two-part closure having a top member 202 from which a depending peripheral rim 208 extends. The closure 200 shown in FIG. 8 acts as a bore and top seal which is dynamically sealed in and on the mouth opening 6.

[0073] In the embodiment shown in FIG. 8, the engagement means on the exterior of the annular periphery of the mouth opening 6 are not shown. However, it will be appreciated that such engagement means are provided and are arranged to be engaged by screw threads 220 provided on the depending rim 208.

[0074] The top member 202 of the closure 200 comprises, as can be seen in FIG. 9, a substantially circular, planar, disc 212 with a flat outer surface and a plurality of stiffening ribs 210 on its internal surface. The top member 202 has a radially extending, circumferential portion 213 extending around the outer circumference thereof. A first, inner annular rim 214 and a second, outer annular rim 216 each depend downwardly from said circumferential portion 213. In the embodiment illustrated, there are six radially extending internal ribs 210 which extend from the centre of the disc 212 to the downwardly depending inner rim 214. It will be seen that the two rims 214 and 216 together define a downwardly open annular channel 224 which extends annularly around the circumferential portion 213 of the top member 202.

[0075] The top member 202 may be made of a plastics material or of a metal. Where it is formed of a plastics material it may be a coextrusion or co-injection of foil and polypropylene or other plastics material. It is possible, for example, to mix the plastics material with an oxygen scavenger before moulding the disc 212.

[0076] As the top, external surface of the central disc 212 is substantially planar, instructions for use and/or advertising material may be affixed to the external surface of the top member 202.

[0077] Preferably, the external diameter of the inner rim 214 of the top member 202 is the same as, or slightly larger than, the internal diameter of the mouth opening 6 of the container. This means that the top member 202 has to be forced into position during closure of the container whereby a very good and efficient seal is produced within the mouth opening 6.

[0078] As described previously, a sealing member, such as a gasket (not shown), may be provided in the channel 224 in the top member 202. Additionally and/or alternatively, sealing compound, such as compound 122, may be provided in the channel 224. In the embodiment shown in FIG. 8, the top of the mouth opening 6 of the container is provided with a projection 260. This projection is made stiff so that it can deform the surface of the channel 224 with which it comes into contact. In this way, further enhanced sealing of the closure on the mouth opening 6 can be achieved.

[0079] As previously, the rim 208 of the closure is engaged on and depends from the top member 202 and is rotatably engaged by way of screw threads 220 on screw threads (not shown in FIG. 8) on the outer periphery of the mouth opening 6.

[0080] It will be seen from FIG. 8 that the rim 208 has a radially extending flange 230 which, in the closed position of the closure 200, engages on the top, external surface of the radially extending circumferential portion 213 of the top member 202. Thus, when the separate rim 208 of the closure is engaged on the mouth opening 6 to close the container, the rim 208 holds the channel 224 of the top member 202 in position on the mouth opening 6 to make and retain a pressure withstanding seal therebetween. Where the contents of the container are carbonated, the pressure of the contents will tend to push the inner depending rim 214 of the top member 202 against the mouth opening 6 whereby a further pressure seal is made and retained. The strengthening ribs 210 on the top member 202 prevent bowing of the disc 212 outwardly by the pressure of the contents.

[0081] Where the contents of the container are beer, for example, it is generally preferred to fill the container at a temperature of 3° C. or lower to maintain its carbonation during filling. However, the container has to be capable of withstanding the pressure of its contents and maintaining the seal of its closure at temperatures up to 40° C. In a preferred embodiment, at least the material of the separate rim 208 of the closure 200 and of the body of the container defining the mouth opening 6 is the same so that the two elements react similarly as the container is subjected to differing temperatures. Preferably, both the container body and at least the separate rim 208 of the closure are of an appropriate plastics material.

[0082] It will be appreciated that the container and its closure 200, as illustrated in FIGS. 8 and 9, provide sealing against the pressure of the container contents both within the inner diameter, or bore, of the mouth opening 6 and at the top surface of the mouth opening. This top and bore seal is, because of the construction of the closure 200, dynamically reactive to the pressure of the contents. Nevertheless, because only the separate rim 208 of the closure has to be rotated to release the closure, opening of the container by removal of the closure 200 is relatively simple. Once the rim 208 is rotated in an opening direction, the top seal begins to be released whereby the bore seal can similarly be released. In general, the construction of the closure and the sequential release of the seals thereof enable gas to be vented from the container so that there is no danger of missiling of the closure. However, pressure venting means to further allow venting on opening and thereby prevent missiling may also be provided.

[0083] FIG. 10 show an alternative embodiment, similar to that of FIG. 8, but with an annular projection 270 formed on an interior surface of the separate rim 208. When the closure 200 is in its closed position, the outer depending rim 216 of the top member 202 is pinched between the separate rim 208 and the mouth opening 6 of the container to assist in sealing the container. The pinching action is able to maintain the seal even where there are different amounts of creep or contraction in the plastics material of the container and the closure.

[0084] It will be appreciated that variations to and modifications in the embodiments as described and illustrated may be made within the scope of the invention as defined in the appended claims.

Claims

1. The combination of a container for a carbonated beverage and a rotatable closure for the container,

the container comprising a body member having an opening at one end thereof, said opening having an annular periphery and defining an unrestricted mouth opening for the container,

the rotatable closure comprising a top member having a periphery and a separate depending rim, the rim being engageable with the periphery of the top member and being rotatable relative to the top member, and

the combination further comprising first external engagement means formed on said body member proximate to said opening and second engagement means formed internally of the rim of said rotatable closure, said first and second engagement means being engageable to allow said rotatable closure to be engaged on and removed from the container by rotating the rim of the rotatable closure relative to the opening of the container,

wherein the rotatable closure is selectively rotatable to a closed position that closes and seals said opening and being arranged, in said closed position, to withstand a pressure of and substantially maintain a pressurized state of the contents of the container when the container has been filled with a carbonated beverage,

wherein the top member of the rotatable closure comprises a substantially circular panel and a radially extending, circumferential portion extending around the outer circumference of said circular panel, and a first, inner annular rim, and a second, outer annular rim, each said rim depending downwardly from said circumferential portion,

said inner and outer rims being spaced to define therebetween a downwardly open annular channel extending around the circumferential portion of the top member, wherein the annular periphery of the container opening is received within said annular channel in the closed position of the rotatable closure to provide a seal at the top of the container opening, and,

in the closed position of the rotatable closure, the inner rim of the top member is engaged against an interior surface of the annular periphery of the container opening to provide a seal within the container opening, and

wherein the circular panel of the top member is stiffened to withstand the pressure of the contents of the container.

2. A combination according to claim 1, wherein the circular panel is siffened by a plurality of stiffening ribs formed on an interior surface of the circular panel.

3. A combination according to claim 1, wherein the annular periphery of the container opening is provided with an annular projection for receipt within, and engagement with, the annular channel of the top member in the closed position of the rotatable closure.

4. A combination according to claim 1, wherein an internal surface of the separate depending rim carries an annular projection arranged to engage the second, outer annular rim of the top member in the closed position of the rotatable closure.

5. A combination according to claim 1, wherein the material of the body member of the container and the material of the separate depending rim of the rotatable closure are the same.

6. A combination according to claim 1, further comprising pressure venting means defined by at least one of said container and said rotatable closure for allowing pressure to be vented from the interior of the container upon rotation of the rim of said rotatable closure out of the closed position during opening of the container.

7. A combination according to claim 6, wherein said pressure venting means comprise one or more slots extending through said rotatable closure.

8. A combination according to claim 6, wherein said pressure venting means comprise one or more slots extending through said container.

9. A combination according to claim 6, wherein said pressure venting means comprise means associated with said first and second engagement means for imparting a two stage opening movement of said rotatable closure relative to the opening of the container.

10. A combination according to claim 1, wherein said unrestricted mouth opening for the container has a diameter which exceeds 30 millimeters.

11. A combination according to claim 10, wherein said unrestricted mouth opening has a diameter exceeding 50 millimeters.

12. A combination according to claim 1, wherein the top member of said rotatable closure is made of metal.

13. A combination according to claim 1, wherein the top member of said rotatable closure is made of plastics material.

14. A combination according to claim 13, wherein an oxygen scavenger has been combined with said plastics material.

15. A combination according to claim 1, wherein the separate depending rim of the rotatable closure is made of a plastics material.

16. A combination according to claim 15, wherein the body member of the container is made of a plastics material which is the same as the plastics material of the separate depending rim.

17. A combination according to claim 1, wherein said rotatable closure is removable from the container by rotating the rim of the rotatable closure relative to the opening of the container, and wherein rotation of said closure through less than one complete revolution thereof is effective to enable its removal.

18. A combination according to claim 1, wherein said first and second engagement means comprise lugs and/or stops provided on one of the rim and of the container, and corresponding recesses, guides and/or stops provided on the other of the container and of the rim.

19. A combination according to claim 1, wherein said first engagement means comprises an external screw thread provided on said container around said opening.

20. A combination according to claim 19, wherein said external screw thread on the container is interrupted.

21. A combination according to claim 19 or claim 20, wherein said second engagement means further comprises a plurality of lugs on the interior of the rim of said rotatable closure for engagement with said external screw thread.

22. A combination according to claim 19 or claim 20, wherein said second engagement means comprises an internal screw thread on the rim of said rotatable closure for engagement with said external screw thread.

23. A combination according to claim 1, wherein said second engagement means comprise an internal screw thread on the rim of said rotatable closure.

24. A combination according to claim 23, wherein said internal screw thread is interrupted.

25. A combination according to claim 23 or claim 24, wherein said screw thread varies in pitch.

26. A container according to claim 23, wherein said first engagement means comprise a plurality of lugs provided on said container and spaced around said opening, said lugs being engageable with said internal screw thread.

27. A combination according to claim 6, wherein said second engagement means are formed on an inner surface of said rim of the rotatable closure, and said pressure venting means are associated with said second engagement means.

28. A combination according to claim 6, wherein said pressure venting means comprise one or more slots extending in said rim of the rotatable closure.

29. A combination according to claim 27 or claim 28, wherein said pressure venting means comprise means associated with said second engagement means and arranged to cause said rotatable closure to require a two stage opening movement.

30. A combination according to claim 27 and claim 28, wherein said pressure venting means comprise one or more anti-missiling stops associated with said second engagement means.

31. The combination of a container for a carbonated beverage and a rotatable closure for the container,

the container comprising a body member fabricated from plastics material and having an opening at one end thereof, said opening having an annular periphery and defining an unrestricted mouth opening for the container,

the rotatable closure comprising a top member having a periphery and a separate depending rim, the rim being engageable with the periphery of the top member and being rotatable relative to the top member, and

the combination further comprising first external engagement means formed on said body member proximate to said opening and second engagement means formed internally of the rim of said rotatable closure, said first and second engagement means being engageable to allow said rotatable closure to be engaged on and removed from the container by rotating the rim of the rotatable closure relative to the opening of the container,

wherein the rotatable closure is selectively rotatable to a closed position that closes and seals said opening and being arranged, in said closed postion, to withstand a pressure of and substantially maintain a pressurized state of the contents of the container when the container has been filled with carbonated beverage,

wherein the top member of the rotatable closure comprises a substantially circular panel and a radially extending, circumferential portion extending around the outer circumference of said circular panel, and a first, inner annular rim, and a second, outer annular rim, each said rim depending downwardly from said circumferential portion,

said inner and outer rims being spaced to define therebetween a downwardly open annular channel extending around the circumferential portion of the top member, wherein the annular periphery of the container opening is received within said annular channel in the closed position of the rotatable closure to provide a seal at the top of the container opening, and,

in the closed position of the rotatable closure, the inner rim of the top member is engaged against an interior surface of the annular periphery of the container opening to provide a seal within the container opening,

and wherein pressure venting means are defined by at least one of said container and said rotatable closure, for allowing pressure to be vented from the interior of the container upon rotation of said rim of said rotatable closure out of said closed position during opening of the container.