WO2009115811A1

WO2009115811A1 - Sealed container

Info

Publication number: WO2009115811A1
Application number: PCT/GB2009/000744
Authority: WO
Inventors: Anthony Henry Joseph Fraser; John Hein
Original assignee: Meadwestvaco Corporation
Priority date: 2008-03-19
Filing date: 2009-03-19
Publication date: 2009-09-24
Also published as: EP2268557B1; ATE548289T1; CN102046489A; BRPI0908977A2; EP2268557A1; US20110100988A1

Abstract

A container (1) for the storage of a carbonated drink, comprising a container body with an opening that defines an axis and a removable closure (3) for closing the opening, the closure including a foil (2) for bonding to the container to close the opening in a gas-tight manner, the foil also being connected to, or interacting with, the closure, such that initial rotation of the closure in a loosening direction relative to the container body distorts or deforms the foil in a manner such that further rotation of the. closure results in a peel force being applied to the bond between the foil and the container.

Description

SEALED CONTAINER

TECHNICAL FIELD

The present invention relates to containers, and particularly relates to containers for supplying beverages to consumers. The invention has particular utility for the storage and supply of carbonated and other sparkling drinks, but may also be. used with other types of drinks or other contents.

BACKGROUND ART

For many years there has been a desire among drinks suppliers and container manufacturers to provide practical wide-mouth beverage supply containers which consumers may drink from comfortably in the same manner as from a drinks glass or other drinking vessel, particularly in relation to carbonated drinks such as beers, etc. Despite the tremendous advantages that such a beverage container would provide for drinks suppliers, container manufacturers and consumers alike, no successful beverage container that fulfils these aims has yet been produced. Consequently, bottles and ring-pull cans currently remain the main practical beverage supply containers for consumers. This is because there are significant technical problems associated with wide-mouth containers to overcome, and no practical solution to the problems has successfully been devised. The present invention aims to provide a practical beverage container, which may be a wide-mouth container (although the invention is also applicable to other types of container, including those with a narrow-mouth opening such as a bottle).

It has previously been proposed to use a foil seal to assist in providing an airtight enclosure for such a container. Various proposals are described in WO2006/000773. One of the problems with using a foil seal with a closure, means that is designed to be moved by rotating relative to the container body, is that the bond between the foil seal and the container has a high shear strength so it is very difficult to break this bond by a twisting action which applies a shear force to the bond.

The present invention seeks to provide a container with closure means capable of with-standing increased pressure within the container, e.g. due to the storage of carbonated or other gas containing liquids and/or elevated temperatures and/or shock loads.

The present invention also seeks to provide a container in which the bond between the foil seal and the container can be more easily broken upon twisting of the closure means in an opening direction.

SUMMARY OF THE INVENTION

A first aspect of the invention provides a container for the storage of a carbonated drink, or other contents, comprising a container body including an opening that defines an axis and removable closure means for closing said opening, the closure means comprising a foil for bonding to the container so as to close said opening in a gas-tight manner, the foil also being connected to, or interacting with, the closure means, such that initial rotation, or other movement, of the closure means in an opening direction relative to the container body distorts or deforms the foil in a manner such that further rotation, or other movement, of the closure means results in a peel force being applied to the bond between the foil and the container.

The arrangement is preferably such that initial rotation of the closure in an opening direction is permitted without disturbing the bond between the foil and the container body. However, this initial rotation moves the closure axially away from the container body such that, upon further rotation of the closure, a peal force is applied to the bond rather than a shearing force. A variety of ways of achieving this are described. This may be achieved, for example, by converting rotation of the closure into a lifting action which is applied to the foil Preferably, the closure means or cap provides physical support for the foil, e.g. by limiting the extent to which it can be distorted by pressure increases within the container and/or by reinforcing the connection between the foil and the container. The cap may be generally annular so it lies over the perimeter of the foil around the periphery of the opening and thus assists in holding the foil in contact with the container. In some cases this may also provide sufficient obstruction to limit bowing out of the foil due to internal pressure but, preferably, the cap extends across the entire foil both to provide further obstruction to deflection of the foil, particularly at the centre thereof, but also to protect the foil against damage from physical contact with external objects which might puncture the foil and/or impair its integrity. The cap thus strengthens and/or protects the connection of the foil with the container and provides puncture protection for the foil.

In a preferred embodiment, a projection is provided on the underside of the closure means to reinforce the bond between the foil and the container body. The projection may comprise a bore seal which presses the foil into contact with an internal surface of the container body. This also facilitates the formation of an induction weld therebetween.

The cap may be made from a range of materials but is preferably formed from a plastics material such as polypropylene (PP), polyethylene (PE) or polyethylene terephthalate (PET) and may be formed by injection moulding.

Preferably, the cap is releasably secured to the container body, by a snap-fit and/or screw thread (either directly or via a collar) which securely hold it on the container and is removable from the container body by rotating relative thereto. Preferred embodiments of the invention have a cap-on-collar closure means in which the cap is secured to the container body via a collar so that the container body does not need to be provided with thread features. Suitable forms of capon-collar closure means are described in WO2006/000774, WO2007/091068 and WQ.2008/012539. Venting means are also preferably provided to allow pressure within the container to be vented prior to complete removal of the cap and/or the foil. Controlled venting may, for example, be provided as the foil is peeled off the container.

The foil is preferably attached to the container around a perimeter of the opening by induction heating. Preferably, the attachment to the container, whilst being strong enough to withstand the desired level of pressure within the container, is weaker than the attachment to the cap so that upon removal of the cap, the foil is separated from the container but remains attached to and is removed with the cap.

Preferably, the foil is secured to the closure means so as to be removed therewith when the closure means is removed from the container body; so the container can be opened in a single step. The foil should be attached more securely to the closure means than it is to the container body so it remains attached thereto when the bond with the container body is broken. The foil may be mechanically or adhesively secured to the closure means or welded thereto

References to foil herein include impervious laminates comprising one or more layers which give the foil strength and one or more layers for attaching the upper and/or lower surface of the foil to another article. Such foils are widely used in other fields. Where the foil is to be secured by induction heating, an electrically conductive layer is required. This is usually a metallic layer and most commonly a layer of aluminium. The electrically conductive layer is typically provided with one or more plastic coatings, e.g. of polyethylene, which melt when the electrically conductive layer is heated to bond the foil to an article held in contact therewith. Such foils can be bonded to both glass and plastic articles. Preferably, the foil is constructed so that it can be pre-shaped to facilitate easy assembly of the closure means and bonding to the container body.

The foil is preferably secured to the container in a manner capable of withstanding elevated internal pressures. Laminated foils comprising two or more layers of aluminium are now available which are capable of withstanding pressures of up to 5-6 bar (as might arise if a carbonated drinks container is subject to high temperatures). As well as preventing the egress of gas, the foil also protects the container from ingress of gas, so helps prevent contamination of the beverage and prevent it becoming stale. With such a foil, the beverage container can have a shelf-life of several months, eg 4 months or more (as typically required for beers and other carbonated drinks sold in containers).

In some embodiments, the foil may be constructed so as to reduce the amount by which it deflects under a given internal pressure. This may be achieved, for example, by suitable choice of materials for a laminate foil. In particular, if. one layer of the laminate is more flexible or stretchable in one direction compared to a perpendicular direction, a crossed-laminate may be used, i.e. in which two such layers are orientated in different directions (preferably perpendicular to each other).

When the foil is secured to the cap adhesively, it is preferred that the upper surface of the foil comprises aluminium, ie without a plastic coating, to help create a strong bond. When the foil is secured to the cap mechanically or by welding, it is desirable in some embodiments for the plastic coatings on the two sides of the foil to have different melting points.

The foil may also provide tamper evidence in that if the foil is intact it provides the consumer with reassurance that the product has not been tampered with or previously opened or otherwise exposed to the external atmosphere. This function is further enhanced if the cap is formed of a transparent material.

The container body is typically formed of a plastics material, e.g. polyethylene terephthalate (PET), or of glass. The container may be shaped to resemble a conventional drinking vessel, e.g. a beer glass, shaped in the form of a bottle or of some other shape. The opening of the container body preferably is a wide-mouth opening. By a "wide-mouth opening" is meant (at least in its broadest sense) an opening of a size suitable for a person to drink from the container in the same manner as from a drinks glass or similar drinking vessel. That is, in its broadest sense, the wide-mouth opening of the container (for embodiments of the invention having a wide-mouth opening) generally renders the container suitable as a drinking vessel, from which a beverage supplied in the container may be conveniently drunk (in contrast to conventional narrow-necked bottles and ring-pull cans which generally are not regarded as comfortable drinking vessels). In practice, , this requirement means that the diameter of the wide-mouth opening of the container will normally need to be at least 40mm, preferably at least 45mm, and more preferably at least 50mm. Additionally, an excessively wide opening is generally difficult for the consumer to drink from, and thus the wide-mouth opening preferably has a diameter no greater than 150mm, more preferably no greater than 100mm, and especially no greater than 80mm. A particularly preferred diameter range for the wide-mouth opening is 50 to 80mm, and examples of particular preferred diameters included 53mm and 63mm.

The container may also have a narrow-mouth opening, e.g. a bottle-type opening. Such an opening may for example, have a diameter of 40mm or less. Conventional standard bottle mouth sizes include diameters of 28mm and 38mm and the opening may be of this size.

The container body (whether wide-mouth or narrow-mouth) preferably has no thread or thread segments on its exterior so a smooth lip can be provided. Consequently, the container body preferably is comfortable for a consumer to drink directly from the container body.

As indicated at the beginning of this specification, although the containers described herein may be used for other types of beverages, the invention is particularly suited to the storage and ^"supply of carbonated and other sparkling ^' drinks, for example beers, ciders, sparkling wines (including champagne), other fizzy alcoholic beverages, and non-alcoholic fizzy and sparkling beverages, including sparkling water and carbonated soft drinks or the storage of any other liquid capable of generating an elevation pressure within the container.

Other preferred and optional features will be apparent from the following description and from the subsidiary claims of the specification.

The invention also relates to the use of a beverage container of the type described for containing a carbonated beverage and to a method of sealing such a container.

BRIEF DESCRIPTION OF DRAWINGS

Figures IA to ID show views of a first embodiment of a container according to the present invention. Figures IA and IB are perspective views illustrating folding over of a foil seal. Figure 1C is a cross-sectional view through the container when closed and Figure ID is an enlarged view of part of Figure 1C during removal of the closure means.

Figures 2A to 2D show views of a second embodiment of a container according to the present invention. Figure 2A is a cross-sectional view of the container when closed and Figure 2B is an enlarged view of part of Figure 2A. Figure 2C is a cross-sectional view during removal of the closure, means and Figure 2D is an enlarged view of part of Figure 2C.

Figure 3 is a cross-sectional view of part of a modification of the second embodiment shown in Figure 2.

Figures 4A to 4D show views of a third embodiment of a container according to the present invention. Figure 4A is a perspective view of a foil seal secured to a container body. Figure 4B is a cross-sectional view of the container when closed. Figure 4C is a perspective view of the foil seal during removal of the closure means (which is omitted for clarity). Figure 4D is a cross-sectional view of the container during removal of the closure means. Figure 5 is a perspective view of a foil seal secured to a container body in a modification of the third embodiment shown in Figure 4.

Figures 6A to 6D show views of a fourth embodiment of a container according to the invention. Figure 6A is a perspective view of the parts thereof prior to assembly. Figure 6B is a cross-sectional view of the container when closed. Figures 6C and 6B are perspective views of the foil seal during removal of the closure means (which is omitted for clarity).

Figures 7 A - 7B show views of a fifth embodiment of the invention. Figure 7A is a cross-sectional view of part of the container when closed and Figure 7B is a similar view during removal of the closure means.

Figures 8A - 8F show views of a sixth embodiment of the invention. Figure 8A is a cross-sectional view of part of a closure, prior to assembly (with the container body omitted for clarity). Figure 8B is a cross-sectional view of the closure once, assembled on a container body. Figure 8C is a cross-sectional view illustrating opening of the container. Figure 8D is a cross-sectional view illustrating re- closure of the container. Figure 8E is an enlarged cross-sectional view similar to Figure 8B and Figure 8F is a perspective view from beneath, part broken away, of components of the closure shown in Figures 8A-8E.

Figures 9A - 9D show a further embodiment of the invention. Figure 9A is a cross-sectional view of a closure, prior to assembly with a container body. Figure 9B is a cross-sectional view of the closure once assembled on the container body. Figure 9C is a cross-sectional view illustrating opening of the container. Figure 9D is a cross-sectional view illustrating re-closure of the container DESCRIPTION OF PREFERRED EMBODIMENTS

Figure 1 shows a container comprising a container body 1 with a widemouth opening IA surrounded by a lip IB, a foil seal 2 applied across the opening IA and closure means in the form of a cap 3 and collar 4.

The foil seal 2 is secured to the top of the lip IB, e.g. by induction welding, along a weld line 2A as shown in Figure IA. The foil seal 2 is of a diameter which projects beyond the lip IB of the container body 1 and the outer part thereof is then folded back on itself as shown in Figure IB. The folded back portion 2B of the foil, which has a pleated form, is then welded to the inner surface of the cap 3 along the weld line 2C which is radially inwards of the weld line 2A.

Figure 1C shows a cross-section of the cap 3 when in the closed position on the container body 1. When the cap 3 is rotated in the loosening direction, as indicated by arrow Al, it results in axial movement of the cap 3 relative to the collar 4 and the container body 1, as indicated by arrow A2. It will be appreciated that initial rotation of the cap 3 is permitted by the pleated form of the folded back portion 2B of the foil 2 without disturbing the bond 2A between the foil 2 and the container body 1.

As the cap 3 rises (as it is unscrewed), the portion 2B of the foil becomes taut. so further rotation and axial movement of the cap 3 applies a peeling force to the; bond 2A via the portion 2B as illustrated in Figure ID. The force applied by the portion 2B to the bond 2A has both upward and inward components, as indicated by arrow A3, so that the foil 2 is peeled away from the container lip IB.

Once the foil 2 has separated completely from the container body I₁ it is removed with the container lid 3 (it still being welded to the underside thereof).

To minimise the risk that the folded back portion of the foil 2B does not bond to the upper surface of the portion of the foil extending across the opening IA, the upper surface of the foil (in the position shown in Figure IA) may comprise an aluminium_. layer.

Figure 2 illustrates a second embodiment having a container body 11, a double layer foil 12 instead of a folded back foil, a cap 13 and collar 14.

The foil 12 comprises an upper foil 12A and a lower foil 12B. The lower foil 12A is welded to the top of the lip HA of the container body along weld line 12C. The upper foil 12A has its lower surface welded to the upper surface of the lower foil 12B around the perimeter thereof along weld line 12D (see Figure 2B) and has its upper surface welded to the interior of the cap i3 at a weld area 12E radially inward of the weld lines 12C and 12D.

The upper and lower foil 12A, 12B are thus bonded to each other only around their perimeter and so form an empty pillow, e.g. in the form of an empty, circular tea-bag. To prevent the internal surfaces of the upper and lower foils 12A, 12B bonding to each other these are preferably formed by aluminium layers (except in the area of weld line 12D).

When the cap 12 is rotated in the loosening direction (indicated by arrow Al) and the cap rises axially (indicated by arrow A2), the central portions of the upper and lower foils 12A, 12B separate slightly as illustrated in Figures 2C and 2D. The upper foil 12A is also twisted during this movement of the cap 13. Once the upper foil 12A has been distorted to a certain degree, it becomes taut and applies a peeling force to the bond line 12C. This peeling force has an ^" upward and radially inward component as indicated by arrow A3 in Figure 2D.

Figure 3 illustrates a modification of the embodiment shown in Figure 2. In this case, the lower foil 12B is bonded to an inner portion of the container body lip HA (rather than an upper portion or outer portion thereof). The underside of - the cap 13 is also provided with a projection 13A which, when the cap is in the closed position, provides reinforcement of the bond between the lower foil 12B and the container body 11 by pressing against the perimeter of the double foil layer. In this case, the peel force acts upwards and outwards on the bond between the lower foil 12B and the container body 11, ie the peel initiates at the radially inward end of the welded bond. A further embodiment of this type is described below with reference to Figures 8A to 8F.

Other arrangements can be envisaged in which initial rotation of the cap is permitted by a portion of the foil seal without disturbing the bond line with the container so that a peeling force can then be applied to this band line by further rotation of the cap.

Figures 4-6 illustrate further embodiments in which this initial movement is enabled or facilitated by a line of weakness or tear initiator in the foil seal.

As indicated above, foils are now available which are capable of withstanding very high bursting pressures. This type of foil is very strong so it is very difficult to tear or rupture the foil unless a weak point or tear initiator is provided therein (unless the foil is subject to cutting or piercing by a sharp edge or sharp point).

The embodiment shown in Figure 4 comprises a container body 21, a foil seal 22, a cap 23 and a collar 24. The foil 22 is welded to the container lip 21A along a weld line 22A and projects beyond the lip as shown in Figure 4A. The projecting portion of the foil 22 is provided with one or more tear initiators, e.g. in the form of a slit or cut-out 22B and the upper surface of the foil 22A is locally welded to the interior of the cap 23 by a weld area 22C on the projecting portion of the foil and adjacent the cut-out 22B.

In this case, when the cap 23 is rotated in a loosening direction, as indicated by arrow Al, the portion of the foil 22 welded to the underside of the cap 23 is subjected to a circumferential force which is then applied to the tear initiator 22B whereby the foil 22 begins to deform or tear as shown in Figure 4C. As the cap 23 also moves axially (arrow A2) as it is rotated, this portion of the foil 22 is also lifted away from the container 21 so initiating peeling of the foil away from the container 21 (as indicated by arrow A3). Figure 5 illustrates a modification of the embodiment shown in Figure 4. In this case, the foil 22 is provided with a plurality (four in the example shown) of tear initiators 22B at spaced apart positions around its perimeter and a weld area 22C is provided adjacent each of these for bonding the foil 22 to the interior of the cap 23.

Figure 6 shows another embodiment in which a line of weakness is provided in a foil in order to permit an initial unscrewing movement of the cap so that a peel force can then be applied to the foil.

This embodiment comprises a container body 31, a foil 32, a cap 33 and a collar 34. The foil 32 is provided with an upwardly projecting tab 32A and this is secured to the interior of the cap 33 by a localised weld area 32B. The foil 32 also has a circular line of weakness 32C at a radius slightly smaller than the radius of the container lip 3 IA and a tear initiator 32D at the foot of the tab 32A. The foil 32 is bonded to the upper surface of the container lip 31A along a weld line 32E.

When the cap 33 is rotated in a loosening direction (arrow Al), the tab 32A is moved circumferentially (and upwards) and the force applied thereto initiates a tear of the foil 22 at tear initiator 32D. This tear extends inwards until it reaches the line of weakness 32C whereupon it extends around this line of weakness (as illustrated in Figure 6C). The outer ring of the foil 32 is thus peeled away from the container until the whole foil 32 is detached therefrom whereupon it is removed (still attached to the interior of the cap 33) as illustrated in Figure 6D by arrow A2.

In a modification (not shown) of the above embodiment, the tab 32A may be omitted and the localised weld area 32B provided on a portion of the foil adjacent the tear initiator 32D. The weld area 32B may be in line with the weld line 32E although the tear initiator 32D should, of course, be provided just outside the weld line. Figure 7 illustrates an embodiment which operates on similar principles to those described above although implemented in a different manner.

This embodiment comprises a container body 41, a foil 42 on a relatively rigid substrate 42A, a cap 43 and a collar 44.

The foil 42 is provided on the underside of a substrate, e.g. a relatively rigid sheet 42A formed of paperboard or a plastics material, and is bonded to the container lip 41A along a weld line 42B. The sheet 42A projects beyond the lip 41A of the container 41 and lies above an internal projection 43A of the cap 43.

In this case, when the cap 43 is rotated in a loosening direction (arrow Al) and thus moves upwards (arrow A2) relative to the container body 41, the foil 42 is engaged and lifted upwards by the projection 43A which lifts the portion of the sheet 42A which projects beyond the container lip 41A. The foil 42 is thus subjected to a peeling force as illustrated in Figure 7B.

It will be appreciated that this is similar to the above embodiments except that, instead of an upper portion of the foil being bonded to the cap so it is lifted as the cap moves upwards, the foil is lifted by a mechanical engagement with the cap via a substrate which is sufficiently rigid to transmit this upward force to the weld line 42A.

Figures 8A-8F illustrate a sixth embodiment which is a further development of that shown in Figure 3 above-

In this embodiment, a pre-formed foil 52 is mechanically secured to the underside of a cap 53 by engaging apertures 52A in the foil over projections 53A on the underside of the cap 53 and then pressing a securing plate 55 onto the projections 53A so a central portion of the foil is clamped to the underside of the cap 53. Other forms of mechanical connection may be used. The projections 53A may, for example, be hot-studded once the foil 52 is in place so as to enlarge their heads so the foil cannot be removed therefrom. An adhesive connection or welded bond may also be used (as in the embodiments described above).

An annular projection 53B is also provided on the underside of the cap 53 to form a bore seal which fits against the interior of a container body (as described further below).

The foil 52 is preferably, pre-formed so that an outer portion thereof fits around the bore seal 53B and lies against an outer surface thereof (as shown in Figure 8B). Thus, when the cap 53 is assembled onto a container body 51 (as shown in Figure 8B), the outer portion of the foil 52 is trapped between the bore seal 53B and an internal surface 51B of the container body.

The lip of the container body 51 provides a mass of plastic material behind the surface 51B. This is important as part of the surface tends to melt when bonded to the foil 52. As shown in Fig 8A, prior to bonding, the surface 51B has a convex form whereas after bonding it is substantially flat (as shown in Fig 8B).

The bore seal 53B applies pressure to the foil 52 to hold it against surface 51B. It thus re-enforces the bond between the foil 52 and the container body 51. In the closed position shown in Figure 8B, forces on the foil 52 due to elevated pressure with the container can only be applied parallel to the plane of the bond between the foil 52 and the surface 51B, i.e. as a shear force to the bond (and not as a peel-force).

The above arrangement is also advantageous as, during assembly, the bore seal 53B holds the foil 52 tightly against the surface 51B thus facilitating the formation of a bond therebetween by induction welding.

The above arrangement employs a welded bond between the foil 52 and the container body and a welded, mechanical or adhesive attachment of the foil 52 to the cap 53. If the foil is welded to both the container body and the cap, the lower surface of the foil 52 is required to bond to the surface 51B of the container and the upper surface of the foil 52 is bonded to the underside of the cap 53. However, the formation of a bond between the upper surface of the foil 52 and the bore seal 53B should be avoided. One way to do this is to laminate a different material onto the two sides of the foil 52 with different melting temperatures, eg two different forms of polyethylene. Thus, the upper surface may be designed to weld at a given temperature, say 210 degrees C, and the lower surface at a lower temperature, say 190 degrees C. A welding temperature between these two temperatures can therefore be used to weld the lower surface of the foil to the surface 51B without the upper surface of the foil being welded to the bore seal 53B. A higher welding temperature can then be used in a localised area (away from the bore seal 53B) to weld the upper surface of the foil to the underside of the cap.

If a foil is used which has a plastic coating on both sides, the above feature can be used to avoid the Upper surface of the foil becoming welded to the bore seal, however, the foil is attached to the cap. Alternatively, the plastic coating on the upper side of the foil can be omitted or removed in the vicinity of the bore seal.

When the container is to be opened, rotation of the cap 53 relative to the collar 54 causes the cap to begin to rise relative to the container body 51 so the bore seal 53B moves upwards and releases the pressure applied to the outer portion of the foil. Rotation of the central portion of the foil 52 attached to the underside of the cap 53 thus causes a peel-force to be applied to the bond between the foil and the container body (in the manner , described in the embodiments referred to above) and as illustrated in Figjjre 8C.

Although the foil 52 remains secured to the underside of the cap 53, it does not interfere with a temporary re-application of the cap 53 to the container body 51 (e.g. to cover the contents and/or reduce the risk of spillage once the seal between the foil 52 and the container body 51 has been broken). Figure 8D illustrates re-application of the cap 53 to the container body 51 in this manner. Figure 8E is an enlarged version of Figure 8B. A further advantage of the arrangement shown is that the bore seal feature 53B can be formed in an injection moulding without the need to use side cores in the mould as undercut features of the skirt of the cap 53 can be formed via aperture 53D provided in the upper portion of the cap 53. It also shows that the edge of the foil 52 adjacent the bore seal 53B stops short of the underside of the cap, This is important to avoid the edge of foil 52 boding to the cap.

Figure 8F shows a view of the cap from the underside, showing the projections 53A for receiving the clamping plate 55 and the annular bore seal 53B.

The above embodiments illustrate containers in which the closure comprises a cap which fits over a collar by means of which the cap is secured to the container body Other forms of closure may however be used which do not employ such a collar. A cap may, for example be applied directly to the container body and secured thereto by a band or collar around the exterior of the cap, eg as described in WO2006/003453. Other fastening means may be used to help secure the cap to the container body. Generally, for wide mouth containers from which a consumer may drink, the provision of a thread on the container body is preferably avoided. However, the provision of thread features on container bodies having a narrower opening, eg a bottle neck, may be acceptable.

Figures 9A-9D illustrate another embodiment in which a seal similar to that described above in relation to Figure 8 is used with a single piece closure 63 applied to a narrow-mouth opening of a container body 61. The closure 63 is designed to be pushed onto the container body 61 in an axial direction so that parts of a skirt 63C of the cap snap-fit with features 61C of the neck of the container body 61 but to be released from engagement with those features by rotation between the cap 63 and the container body 61. Such a closure (without a foil seal) is described further in WO2007/057659. In this embodiment, a pre-formed foil 62 is adhesively secured to the underside of the cap 63 as shown in Fig 9B (although other forms of connection may be used).

An annular projection 63B is provided on the underside of the cap 63 to form a bore seal which fits against the interior of the container body 61.

As in the previous embodiment, the foil 62 is pre-formed so that an outer portion thereof fits around the bore seal 63B and lies against an outer surface thereof (as shown in Figure 9B). Thus, when the cap 63 is assembled onto the container body 61 (as shown in Figure 9B), the outer portion of the foil 62 is trapped between the bore seal 63B and an internal surface 61B of the container body,

The foil preferably has a plastic coating on its underside for bonding to the surface 61B but no coating on its upper side so the metal layer of the foil can be adhered directly to the underside of the cap 63.

The bore seal 63B applies pressure to the foil 62 to hold it against surface 61B. It thus re-enforces the bond between the foil 62 and the container body 61. In the closed position shown in Figure 9B, forces on the foil 62 due to elevated pressure with the container can only be applied parallel to the plane of the bond between the foil 62 and the surface 61B, i.e. as a shear force to the bond (and not as a peel-force).

When the container is to be opened, rotation of the cap 63 relative to the container body 61 causes the cap 63 to begin to rise relative to the container body 61 so the bore seal 63B moves upwards and releases the pressure applied to the outer portion of the foil 62. Rotation of the central portion of the foil 62 attached to the underside of the cap 63 then causes a peel-force to be applied to the bond between the foil 62 and the container body 61 (in the manner described in the embodiments referred to above) and as illustrated in Figure 9C. Th e foil 62 remains secured to the underside of the cap 63, but does not interfere with a temporary re-application of the cap 63 to the container body 61 (e.g. to cover the contents and/or reduce the risk of spillage once the seal between the foil 62 and the container body 61 has been broken). Figure 9D illustrates re-application of the cap 63 to the container body 61 in this manner.

Whilst, in many cases, the closure will be secured to the container body such rotation of the closure relative to the container body is required to remove the closure therefrom, in some cases other forms of movement may be required, eg a lifting, bending or prising movement, instead of rotation. Examples of this are also described in WO2006/003453. In such cases, the closure may still be rotated to some degree in order to twist the foil and hence initiate a peeling force on the foil prior to the closure being removed by a lifting, bending or prising movement. In other cases, a pealing action may be initiated by a lifting, bending or prising movement without the need for any rotation of the closure. Embodiments such as those shown in the Figures may, for example, be modified so the a pealing action is initiated by lifting a portion of the closure.

It will be appreciated that all the above embodiments decouple the point of attachment of the foil to the container from its attachment to the cap thus allowing the cap to start turning and lifting off before meeting the resistance of the shear strength of the foil to container bond and the geometry is arranged such that the force then applied to the foil to container bond is a peeling force so the foil can be peeled away from the container.

The embodiments described enable a foil to be used so as to provide a better seal of the container than provided by conventional caps and seals, enables the majority of the pressure retention to be provided by the foil (so reducing the performance requirements, and hence the cost, of the cap) and provides the consumer with a convenient and intuitive opening action for removing the cap and the foil in one simple action.

Claims

1. A container for the storage of a carbonated drink, or other contents, comprising a container body including an opening that defines an axis and removable closure means for closing said opening, the closure means comprising a foil for bonding to the container so as to close said opening in a gas-tight manner, the foil also being connected to, or interacting with, the closure means, such that initial rotation, or other movement, of the closure means in an opening direction relative to the container body distorts or deforms the foil in a manner such that further rotation, or movement, of the closure means results in a peel force being applied to the bond between the foil and the container.

2. A container as claimed in claim 1 in claim 1 in which the foil is bonded to the container body and to the closure means, the bond to the closure means being at a different radial distance from, said axis than the bond to the container body.

3. A container as claimed in claim 2 in which the foil is secured to an interior of the closure means and bonded to a lip of the container body.

4. A container as claimed in claim 3 in which the foil is bonded to an inner portion of the container body lip.

5. A container as claimed in claim 4 in which the underside of the cap has a projection which, when the cap is in the closed position, provides reinforcement of the bond between the foil and the container body.

6. A container as claimed in claim 5 in which the projection provides a bore seal which presses the foil into close contact with an internal surface of the container body.

7. A container as claimed in 3 in which the foil has a portion which extends beyond the lip of the container body and is folded back beneath the closure means.

8. A container as claimed in any preceding claim in which the foil comprises a lower foil attached at its^' periphery to the container body and an upper foil which is attached at its periphery to the periphery of the lower foil and has an upper surface attached to the interior^'of the closure means.

9. A container as claimed in claim 1 in which the foil is attached to a lip of the container body and has a portion which extends beyond the lip of the container body, said portion comprising at least one tear initiator and being locally attached to the closure means adjacent the tear initiator.

10. A container as claimed in claim 1 in which the foil is attached to a lip of the container body, has at least one tab projecting therefrom which is attached to the closure means and has a tear initiator adjacent said tab.

11. A container as claimed in claim 10 in which the foil has a line of weakness radially inward of its attachment to the lip of the container body.

12. A container as claimed in claim 1 in which the foil is mounted to a relatively rigid substrate, the foil being attached to a lip of the container body and the substrate extending beyond the lip of the container body to engage with the closure means such that axial movement of the closure means upon rotation thereof in an opening direction lifts the substrate and hence the foil away from the lip of the container body.

13. A container as described in any preceding claim in which the foil is mechanically or adhesively secured to the closure means.

14. , A container as claimed in any preceding claim in which the closure means comprises a cap securable to the container body via a collar.

15. A container as claimed in any preceding claim in which the foil is attached to the closure means so as to be removed therewith when the closure means is removed from the container body.