WO2007045894A1

WO2007045894A1 - Closure caps and bottles or containers to receive same

Info

Publication number: WO2007045894A1
Application number: PCT/GB2006/003911
Authority: WO
Inventors: Michael Corcoran; George Callewaert
Original assignee: Spurcourt Limited; Callewaert, William
Priority date: 2005-10-20
Filing date: 2006-10-20
Publication date: 2007-04-26
Also published as: GB0521405D0

Abstract

A tamper- resistant closure for use with a container comprising a cap (2) and a threaded closure body (3) which is encircled by a resilient cylindrical collar (4) wherein said threaded closure body and said resilient cylindrical collar are arranged to define a channel which can receive a guarantee band of the cap secured thereto and wherein said threaded closure body is provided with means for restricting the annular and/or upwards movement of said guarantee band.

Description

Closure caps and bottles or containers to receive same

The present invention relates to tamper-resistant closures, particularly but not solely for bottles of plastics material. The invention also relates to bottles or other containers to receive such closures.

Closures for plastics bottles generally comprise two parts: a cap part with an attached guarantee or security band and a bottle neck part. The cap part acts as the seal for the bottle and the attached guarantee band becomes detached from this cap part when the cap is unscrewed to open the bottle for the first time. Normally the guarantee band is attached to the cap by a variable number of small frangible links or bridges made from the same plastics material used to form the cap and guarantee band parts. These links are severed on opening. The bottle neck part usually includes a top external threaded section for securing the cap below which is a circular bead or flange against which an inner part of the guarantee band may bear on first opening. Below the level of the bottom of the guarantee band there is normally a further flange which affords some protection against tampering via the inner side of the guarantee band and cap; it also facilitates bottle handling operations.

Such closures are well known in the art.

Usually plastics bottles, including the neck part, are manufactured from either polyethylene terephthalate (PET) or polyethylene naphthalate (PEN): the caps for such bottles are often manufactured from polypropylene (PP), which is a relatively hard but flexible material and accordingly ensures the function of the cap: polyethylene (PE) or more particularly high density polyethylene (HDPE) although being a softer and more flexible material is used as an alternative.

US Patent 6,338,414 discloses a claimed improved cap with a guarantee band manufactured from PE and states that for known caps with guarantee bands manufactured from PP, it is believed to be more or less impossible to lever up such caps in order to gain access to the contents of the bottle without causing visible damage to either the cap and guarantee band or to the bottle and neck. If this supposition is correct the public at large can have confidence that, if there is no visible sign of damage to the bottle or its closure, then the contents of the bottle are in their original state and have not been removed or tampered with.

At the early stages of development of most currently used closure caps and bottles it was intended that the closure should be both tamper resistant and tamper evident. As a result of continued development and cost reduction programmes such closures have generally become less robust and the objective of them being tamper resistant has largely been side lined in favour of a simple tamper evident concept. Tamper evidence comes first from a visual inspection of the closure from which it should be seen that the guarantee band is securely attached to the cap part and second that upon opening, a characteristic resistance to opening is felt followed by visible and possibly audible break away of the guarantee band. Normally, the guarantee band, after dropping a short distance remains attached to the bottle neck and when the cap is replaced a small visible gap exists between the cap and the guarantee band. Provided these criteria are met the consumer has been led to believe that the contents of the bottle have not been exposed since manufacture and that they are safe to drink.

This notion that current closure caps are secure against tampering is illusory and public confidence may be misplaced. Caps complete with the guarantee band attached intact and without any readily visible sign of disturbance or damage may easily be removed and replaced using a variety of simple techniques. Any tool or device which keeps the cap and security band held in a constant position relative to each other may be used. The entire cap and attached guarantee band may then be forcefully removed from the bottle neck by unscrewing without there being any visible damage to any part of the closure or to the links between the cap and the guarantee band. This is because, like the cap, the inner restraining device forming part of the guarantee band is fabricated from either PP or PE and is sufficiently flexible to be distorted and removed intact. The simplest example of such a tool is a piece of strong adhesive tape wound externally tightly around the cap and guarantee band. Alternatively any type of external clamp which holds the two parts firmly in the same position relative to each other, e.g. a simple G clamp, is satisfactory for this duty. No particular skill is needed to remove a cap and guarantee band this way and such a cap can easily be reapplied to the bottle from which it has been obtained so as to result in a product in its original condition. In the meantime, of course, the contents of the bottle could have been tampered with or replaced even. In most cases, because PP and PE closures are flexible, they may be removed simply by the use of levers coupled with stretching and unscrewing movements without the necessity to use any clamping devices or tools. More skill is required for this approach but the use of plastic levers minimises any risk of causing visible damage to the closure. A further method for the removal of the cap and guarantee band intact makes use of the wide difference in the softening temperature of the PET/PEN plastics used to form the bottle and the PP/PE plastics used to form the cap and guarantee band. Thus careful heating of the cap and the neck of the bottle, for example with a hot air blower, will result in differential softening of the two plastics materials. A PET bottleneck softens while an attached PP cap remains relatively unchanged. Under these conditions the bottle neck may be displaced internally laterally to enable the cap and guarantee band to be removed intact and, possibly, by applying a previously discarded cap, the bottle neck may be returned to its previously annular form. Under more extreme conditions it is easily possible using the above techniques to destructively disassemble two bottles and to end up with one complete set of components necessary to put up a complete and apparently un-tampered with product. In every case all the components, both the closure and the bottle will be in their original authentic trade dress.

It is obvious that not all the above tampering methods could easily be used at the point of sale of the drinks products e.g. in a grocery store. However this would not represent an obstacle for a determined tamperer as it would be a simple matter to purchase one product, remove it from the store, recover an intact cap and guarantee band, pocket it, return to the store, open a similar product in a normal way, remove the residual guarantee band and, after tampering with the contents, seal the bottle with the previously obtained intact cap and guarantee band. Alternatively, in a similar scenario, the tamperer could purchase two products, carry out a tampering operation at leisure elsewhere and return one tampered with product to the store on a subsequent visit. -A-

This would be an especially suitable method for carbonated drinks products when prior chilling of the bottle contents would facilitate the tampering operation.

The possibility for tampering with products in the manner outlined above arises not only from the relative ease with which the bottle neck can be softened and the general flexibility of PP and PE plastics materials but also from a ready access to all those parts of the closure required to maintain its integrity. A further less readily apparent factor arises from the manner in which the guarantee band is attached to the cap. Normally the guarantee band is joined to the remainder of the cap by means of a series of small links, spaced around the cap. When the cap is initially turned to unscrew it from the bottle neck the links between the cap and the guarantee band are subjected to a combination of tension and shear forces, such that the links are severed and the cap is released from the guarantee band. This is only possible because the links are relatively weak and not too numerous: on the other hand, the same links must be sufficiently strong to withstand the forces to which they are subjected when the closure is initially applied to the bottle; the strength of the links and the number of them therefore has to be a compromise between two opposing requirements but for closures of PP or PE the links are sufficiently robust to withstand the various removal procedures described above. A yet further factor concerns the lack of any identity association between the cap and bottle, that is to say any one cap and guarantee band, once removed intact, may be reapplied to any bottle.

As a result of the ease with which currently used closures can be compromised as noted above, there is a need for closures with improved security features and resistance to tampering. We have now devised new closures with novel features which meet these needs.

In accordance with the present invention, there is provided a tamper-resistant closure for use with a container comprising a cap and a threaded closure body which is encirc!ed-by a resilient cylindrical collar wherein said threaded closure body and said resilient cylindrical collar are arranged to define a channel which can receive a guarantee band of a cap secured thereto and wherein said threaded closure body is provided with means for restricting the annular and/or upwards movement of said guarantee band.

Typically the resilient cylindrical collar is connected to the threaded closure body via one or more bridges, usually in the form of one or more spokes.

The threaded closure body and resilient cylindrical collar are preferably made of the same material.

The threaded closure body is preferably further provided with a flange, which is situated to define a further channel between the one or more bridges and said flange.

Preferably the one or more bridges extend to form buttresses which connect with said flange.

Typically, for pressurised containers, the thread with which the threaded closure body is provided is non-continuous. The non-continuous sections of the thread are typically in a staggered arrangement.

The threaded closure body may comprise a single start thread or multiple start threads.

The tamper-resistant closure can be used with any suitable container or other storage means. Typical examples include but are not limited to a bottle, a jar and a canister.

The cap and the resilient cylindrical collar may be provided with additional information, such as security information, or may be provided with additional tamper-proof material, such as a heat sensitive coating or heat sensitive printing.

The term 'cylindrical collar' as used herein includes embodiments/structures which are essentially cylindrical-shaped. For example, the term 'cylindrical collar' includes embodiments/structures wherein the walls of the 'cylindrical collar' are straight, barrel- shaped, or are a curved shape at the top and/or the bottom thereof. Embodiments of the present invention will now be described by way of example only and with reference to the accompanying drawings, in which:

FIGURES 1 a -1 c are alternative views of a tamper-resistant closure in accordance with the present invention;

FIGURES 2 a-c illustrate longitudinal and transverse sections through a portion of the tamper-resistant closure shown in Figure 1 ;

FIGURES 2d and 2e illustrate the spatial arrangement of the buttresses and the closure in accordance with the present invention;

FIGURE 2f illustrates a blade which is typically used with a guarantee band as part of the tamper-resistant closure of the present invention;

FIGURE 2g illustrates a section through a portion of the closure showing a cross section of the restraining flange in accordance with the present invention.

FIGURES 3a and 3b illustrate a typical cap which can be used as part of the tamper- resistant closure of the present invention;

FIGURES 4a and 4b illustrate alternative views of a cap which can be used with the tamper-resistant closure of the present invention;

FIGURES 5a-c illustrate a cap and the threaded closure body of the tamper-resistant closure of the present invention having security information printed on the side thereof;

FIGURE 6 illustrates the tamper-resistant closure of the present invention having security information printed separately on the cap and the threaded closure body; and FIGURES 7a-f illustrates schematically how the tamper resistant closure of the present invention can be manufactured.

Referring to Figures 1a-1c and 2a-c, there is provided a tamper-resistant closure 1 comprising a cap 2 and a threaded closure body 3. The upper section 3a of the threaded closure body engages with the cap 2, and the lower section 3b can be formed into a suitable container (not shown).

The upper section 3a is provided with an external annular cylindrical collar 4. The external annular cylindrical collar 4 is connected to the upper section 3a of the threaded closure body 3 via a series of spokes 5. The upper section 3a of the closure body is provided with a screw thread 6. When the contents of the bottle or container are pressurised the screw thread 6 is non-continuous in order to prevent what is known as the 'missile phenomenon' from occurring. The 'missile phenomenon' happens on opening a pressurised container secured with a threaded closure whereby there is a sudden release of pressure when the cap just parts company with the neck, i.e. the pressure has essentially been maintained by a seal formed by the thread. The cap can act like a missile as a result of the sudden release of pressure. The gaps in the thread act to release the pressure immediately on unscrewing the cap thereby avoiding this phenomenon.

In addition, the breaks 7 in the screw thread 6 are staggered in order to prevent a third party from inserting a probe, such as a fine needle or other device, under the cap 2 and into the container.

Connecting the external annular cylindrical collar 4 to the threaded closure body 3 via a series of spokes 5 ensures that any liquid entering the thus formed channel is free to drain away and cannot act as a source of contamination. Such liquid could arise from spillage during filling or from water or other liquid used as a lubricant during the cappmg operation.

The upper section 3a is further provided with a flange 8 which connects with the spokes 5 via a series of buttresses 9. The spokes 5 extend upwards to form the buttresses 9. The bottom face of the flange 8 acts as an undercut against which an inner part of a guarantee band (not shown) of the cap 2 can bear.

Apart from the bottom, the buttresses 9 are provided with three additional external surfaces as shown in Figures 2d and 2e: one of which (9a) is perpendicular to the external wall of the upper section 3a, the second (9b) runs parallel to the external wall of the upper section 3a, and the third (9c) is at an angle to the external wall of the upper section 3a. The perpendicular wall is formed as a result of the face of the buttress forming a 90° angle with a plane tangential to the neck of the container at the point of contact. Alternatively, the faces of the buttresses (other than the parallel face) can be curved as required. In certain cases the angle between the face 9a and the point of contact can be reduced, e.g. by 60° in order to provide the most effective co-operation with different shaped blades (Figure 2e). The shape of the buttresses 9 typically corresponds to the shape of the spokes 5. The buttresses 9 are designed to restrain the movement of blades located on the inside of the guarantee band of the cap 2.

Conventional guarantee bands used in the art maybe provided with blades, which when the cap is unscrewed, bear on a restraining flange and thereby facilitate separation of the guarantee band. Such blades may be of varying shape but in general have only one functioning edge. In contrast the blades incorporated into the guarantee band of the present invention are in general tooth-shaped with three functioning edges. These blades help to restrict the movement of the guarantee band, and as a result prevent the guarantee band from being removed from the container to which it is attached.

A blade which is typically used with the closure 1 is shown in Figure 2f. The blade has three functioning edges 14a, 14b and 14c. The first edge 14a is in contact with the 'perpendicular' restraining face 9a of the buttress 9, the second edge14b is in contact with the flange 8, and the third edge 14c, which is angled, is in contact with the angled face 9c of the buttress 9. The angled edge 14c facilitates displacement of the blade over the buttresses when the cap is screwed on. Advantageously, as shown in Figure 2g, the bottom face of the flange 8 may be angled downwards e.g. by 60° so as to provide the most effective co-operation with different shaped blades. The primary function of the blades and buttresses as well as the flange is to impede the removal of the cap and guarantee band intact. Once separated from the cap it is possible to remove the guarantee band. However, this is more difficult with the closure of the present invention than with those known^'in the art.

Figures 3a and 3b illustrate a cap 10 which can be used as part of the tamper resistant closure of the present invention. The cap 10 comprises an upper portion 11 and a guarantee band 12. The upper portion 11 and the guarantee band 12 are connected via conventional means (not shown), i.e. a variable number of frangible links or bridges which are made from the same material as the cap 10. The guarantee band 12 is provided with blades 13 which act against the flange 8. Some of the blades 13a also act against the buttresses 9.

Once the cap 10 has been placed on the tamper-resistant closure 1 any attempt to remove it would result in the guarantee band 12 being detached from the cap 10 as a result of the buttresses 9 restricting the movement of the blades 13 of the guarantee band 12. The annular movement of the blades 13 of the guarantee band 12 would be limited by the walls of adjacent buttresses 9.

In addition, vertical movement of the cap 10 (when still attached to the guarantee band) is constrained by the tips of the blades 13 of the guarantee band 12 acting against the lower side of the flange 8.

Accordingly, the arrangement of the blades 13 and buttresses 9 would prevent any movement of the guarantee band 12 without irreversibly separating the guarantee band 12 and the cap 10.

The external annular cylindrical collar 4 would prevent the use of any tools or clamps to remove the cap 10 and guarantee band 12 intact.

Figures 4a and 4b illustrate an alternative cap 15 which may be used with the tamper- resistant closure 1 of the present invention. In Figure 4a the cap 15 is provided with a lip 16 which further prevents tampering by a third party. The lip 16 also prevents any spilt liquid or other contaminant from entering the channel formed by the cylindrical collar and the closure.

In Figure 4b the cap 15 is shown with the blades 13a, that would have acted against the buttresses 9, having been removed in order to reduce the possibility of the cap 10 becoming jammed when placed on the tamper proof closure 1. This further also ensures that once the cap 10 has been fitted there is no stretching of the guarantee band 12, and also that the guarantee band 12 falls once the cap 10 has been separated therefrom.

It would be possible to use the guarantee band shown in Figure 4b, i.e. with the blades 13a removed, with the cap shown in Figure 3a. Similarly the guarantee band shown in Figure 3a, i.e. with the blades 13a present, can be used with the cap shown in Figure 4a.

In the event that it is possible to remove and subsequently replace the cap 10 and guarantee band 12 intact, the force and manipulation required would result in damage to the guarantee band 12 at least. Such damage would be visible to a third party through the gaps between the spokes 5. In a similar way, any attempt to manipulate the blades 13 of the guarantee band 12 would result in damage which would also be visible through the gaps in the spokes 5.

The positioning of the spokes 5 is selected such that when the guarantee band 12 and the cap 10 have been separated the guarantee band 12 will drop and a visible gap between the two will be created. This provides additional evidence of the integrity of the tamper proof closure 1 when the cap 10 is fitted.

It will be obvious to those skilled in the art that a workable closure could be provided"by omitting the buttresses 9 (Figure 1b) and by utilising a cap 10 (Figure 3a) or 15 (Figure 4a) with a guarantee band fitted with a full set of blades (Figure 3b) or some other restraining means. However, because the cap and guarantee band could then be removed intact more easily, such a closure would be generally less satisfactory. Third parties can also attempt to remove a cap from a container by first applying heat to soften and deform the cap prior to manipulating it from the container. However when using the tamper proof closure of the present invention this would result in the spokes and external annular cylindrical collar also being deformed. It would, thereafter, be extremely difficult to replace the cap on the container.

One additional means for tampering is to insert a probe under a cap, e.g. the cap 10. The presence of the external annular cylindrical collar 4 and the flange 8 make this extremely difficult to achieve. In addition, the use of staggered breaks 7 in the thread 6 further reduces the possibility of inserting a needle into the container. Current designs for pressurised container necks include gaps in the threaded part to prevent the 'missile phenomenon' as described previously. However, these gaps are stacked vertically thereby potentially allowing a third party to insert a probe into the container.

A further advantage of providing the external annular cylindrical collar is that there is created a surface on which it would be possible to print information, e.g. security information. This would provide a unique identity for both the cap and the closure.

In a preferred design a cap can be shaped such that it is aligned with the cylindrical collar to allow for printing and/or etching of such information. This feature would also help prevent any spilt liquid or other contaminant from entering the gap between the cylindrical collar and the closure. In the cap of Figure 4a, the provision of the lip 16 gives rise to a vertical surface 17. This is contiguous with a surface 18 on the cylindrical collar. It would then be possible to print or etch a single piece of security information over both surfaces 17 and 18. Such information could be in the form of a number, a letter, a barcode, graphic or other suitable information. It would then be impossible to replace the original cap with another cap as the information printed on the new cap would be different from that printed on the cylindrical collar. The difference in the information would be evidence of tampering.

Figures 5 and 6 illustrate alternative examples as to how the printing of such information can be achieved. In addition, the process for printing on a container is rather random in respect of the location of the print on the container. As containers move along a production line they rotate and therefore the precise location of printing relative to a fixed point on the container varies between consecutive containers. Accordingly, if each container is printed with the same information the chances of locating two with such information at the exact same place on the closure would be extremely small. Thus as illustrated in Figure 5b if a cap from one bottle is applied to another, the two parts of the printed information will no longer be correctly aligned thereby providing visible evidence of tampering.

It would also be possible to provide the cap and closure with an adhesive security label, which is difficult with the caps that are currently available. As a resuit of the relative location of the surfaces 17 and 18 (Figure 4a) it would be possible to apply one or more small adhesive labels to connect the two faces. Although the consumer would most probably need to break any such label before removing the cap, e.g. with a thumbnail, it would make undetected removal of the cap almost impossible.

The security of the tamper-resistant closure and cap can also be improved by using heat sensitive markings. Such markings would typically change colour on the application of heat. Accordingly, in the event that a third party attempted to deform the neck of the container using heat the markings would change colour thereby indicating that the tamper-resistant closure had been tampered with.

The tamper-resistant closure of the present invention can be manufactured using known technology. A schematic illustration of how this can be achieved in a single moulding operation is shown in Figures 7a-f. Figure 7a illustrates the mould prior to addition of the plastic material which forms the tamper-resistant closure. The plastic material is injected into the mould at high temperature and pressure. Figure 7b illustrates the mould once the plastic material has been added. Figures 7c-e illustrates the stepwise removal of the sections of the mould thus enabling removal of the tamper-resistant closure. In Figure 7e the closure has begun to be removed from the mould. Figure 7f illustrates the individual sections of the mould once the closure has been completely removed. These individual sections of the mould can then be re-assembled for preparation of another tamper-resistant closure. In this way the tamper-resistant closure can be produced in single moulding operation with both a high volume and high throughput.

Further modifications and improvements may be incorporated without departing from the scope of the invention herein described.

Claims

1. A tamper-resistant closure for use with a container comprising a cap and a threaded closure body which is encircled by a resilient cylindrical collar wherein said threaded closure body and said resilient cylindrical collar are arranged to define a channel which can receive a guarantee band of a cap secured thereto and wherein said threaded closure body is provided with means for restricting the annular and/or upwards movement of said guarantee band.

2. A tamper-resistant closure as claimed in Claim 1 wherein the resilient cylindrical collar is connected to the threaded closure body via one or more bridges.

3. A tamper-resistant closure as claimed in Claim 2 wherein the one or more bridges are in the form of one or more spokes.

4. A tamper-resistant closure as claimed in any of Claims 1 - 3 wherein the threaded closure body and resilient cylindrical collar are made of the same material.

5. A tamper-resistant closure as claimed in any of the preceding Claims wherein the threaded closure body is further provided with a flange.

6. A tamper-resistant closure as claimed in Claim 5 wherein the flange is situated to define a further channel between the one or more bridges and said flange.

7. A tamper-resistant closure as claimed in any of the preceding Claims wherein the one or more bridges extend to form buttresses which connect with said flange.

8. A tamper-resistant closure as claimed in any of the preceding Claims the thread with which the threaded closure body is provided is non-continuous.

9. A tamper-resistant closure as claimed in Claim 8 wherein the non-continuous sections of the thread are typically in a staggered arrangement.

10. A tamper-resistant closure as claimed in any of the preceding Claims wherein the threaded closure body comprises a single start thread or multiple start threads.

11. A tamper-resistant closure as claimed in any of the preceding Claims wherein the tamper-resistant closure can be used with any suitable container or other storage means.

12. A tamper-resistant closure as claimed in Claim 11 wherein the container is a bottle, a jar or a canister.

13. A tamper-resistant closure as claimed in any of the preceding Claims wherein the cap and the resilient cylindrical collar is provided with additional information.

14. A tamper-resistant closure as claimed in Claim 13 said additional information is security information.

15. A tamper-resistant closure as claimed in any of the preceding Claims wherein the closure is provided with additional tamper-proof material.

16. A tamper-resistant closure as claimed in Claim 15 wherein said additional tamper-proofing material is a heat sensitive coating or heat sensitive printing.