TAMPER EVIDENT CLOSURE AND CONTAINER NECK WITH INNER RIDGE

FIELU OF THE INVENTION

The present invention relates to closures for containers, and more particularly to tamper-evident closures for containers and including tamper evident dispensing 5 closures and tamper evident child resistant closures together with corresponding container necks .

BACKGROUND TO THE BSYENTTON

Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of i o common, general knowledge in the field.

There exists extensive prior art in relation to the design and manufacture of tamper-evident closures for containers, such as for example (JS Patents Nos. 4,653,657 (Papavasilopolous), 4,807,771 (Roy), 5,660,288 (Kyman), 6,551,093 (Taha), 6,640,988 (Taha) and Australian Patent application 43435/85 ( patent no ) 5 55087S) the disclosures of which are hereby incorporated into this specification by way of cross-reference. More particularly we refer to Australian patent application 2006203297 filed August 1 ^st 2006 the disclosures of which are hereby incorporated entirely herein.

One problem that exists with prior art tamper-evident closures is the loss of 20 sealing between the closure and container opening prior to the tamper-evidence features operating and insufficient visibility of tamper evidence means.

Containers having a generally annular orifice and annular neck portion further shaped to co-operate with corresponding sealing closure weans including threads and 25 sealing means are used in the packaging of household consumables including liquid and dry goods. Said containers are often manufactured by means whereby a mould consisting on more than one portion is used to shape said containers.

Said mould often leaves on the outer surface of said container a surface irregularity or

30 witness mark, or ridge or projection or groove surface irregularity on and/ or adjacent to the area where said portions of said mould abut. Said mould may also have a pin to

form the inner surface or bore of a container neck and said bore of said container neck is generally parallel with the axis of said neck or said bore is tapered slightly to allow withdrawal of said bore forming pin after forming said bore in said container neck.

Said surface irregularity may occur on the neck of said container and at and or adjacent to the outer surface of said neck and including neck sealing surfaces where corresponding sealing closure means sealingly abut said neck sealing surfaces. Often said corresponding sealing closure means incur the additional cost of inserting at least a compressible disc or wad inserted into said closure after manufacture of said closure . Said compressible disc or wad is designed to overcome the problem of said surface irregularities so that upon application of said closure to said container said wad is compressed between the closure and said neck sealing surfaces and said wad sealingly deforms around said surface irregularities thereby forming a seal between closure and container. However such use of said compressible disc or wad increases the cost of the closure and increases the quantity of waste material per used container

Other sealing means such as a deformable or compressible annular projection from the inside surface of a closure sealingly engaging with at least one area of said corresponding neck sealing surfaces are also known,

The aforementioned sealing means have an undesirable aspect especially in respect of closures attached by thread means to a corresponding threaded container and said closure having tamper evidence means whereby upon removal rotation to unscrew said closure from said container said corresponding sealing closure means are moved away from said neck sealing surfaces such that sealing engagement is lost before said tamper evidence means operate,

In some instances a metal foil disc such as an aluminium disc with a surface coating of heat activated adherent material may replace said compressible wad or be inserted into said closure with said compressible wad and said metal foil disc is sealingly affixed to said container neck by application of heating means such as by induced electric

current. Such use of said metal foil disc solves the problem of loss of seal before tamper evidence means on said closure but increases the cost of the closure.

A further problem in prior art closures and containers is that an effective seal between closure and corresponding container relies on the neck of the container having a smooth annular surface whereby said smooth annular surface sealingly engages with a corresponding annular sealing means on a closure,

Extrusion blow moulded containers typically made in a mould having 2 parts exhibit a mould parting line blemish on the moulded container and container neck where the 2 halves of said mould abut. Said blemish is typically a ridge of plastic raised above the level of the rest of the adjacent container surfaces and including the areas which are intended as sealing surfaces . In extrusion blow moulded containers typically require the use of a flexible plastic disc or similar means interposed between closure and container neck whereby when said closure is fully applied to said container neck said flexible plastic disc deforms over said raised ridge and thereby said flexible plastic disc provides a sealing means between closure and container neck. However, the addition of said flexible plastic disc to a closure assembly increases the total cost of said closure. It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

SUMMARY OF THE INVENTION

One aspect of the present invention deals especially with the need for a proper relationship between sealing means and tamper-evidence means such that the tarnper- evicten.ce means operates prior to the seal being breached. This avoids the possibility apparent with many so-called tamper-evident closures whereby by malicious tampering or inappropriate application torque and/or relaxation of the closure causing the seal between closure and container neck to be breached without the tamper- evidettce means operating and allowing the contents to be degraded by action of atmosphere or the malicious introduction of contaminants, Another aspect of the present invention is a means to at least improve sealing cooperation between closures and containers without the need for a foil or compressible wad and or to improve sealing co-operation between closures and containers so that seal between closure and container neck is not lost until after tamper evidence means has been activated.

The subject matter of Australian Patent No 2004261315 and PCT applications AU2004/ 001035 and AU2005/000222 and AU2005/001968 and priority documents- referred to by the foregoing and other patent documents referred to therein and/or provisional applications referred to by all of said foregoing documents are by reference incorporated herein.

The present invention is a container preferably formed by extrusion blow molding or injection blow moulding from one or more types of polyolefϊn materials and a closure having tamper evidence means and said closure also preferably formed from one or more types of polyolefin materials and said container neck has an annular projection or ridge adjacent to the uppermost surface of said container neck said annular ridge extending inwards towards the axis of said container neck and said closure having a corresponding annular projection adapted to sealiπgly engage with said annular projection or ridges on said container neck such that upon manipulation to remove said closure from said container neck said sealing engagement is maintained until at least said tamper evidence means operates to indicate that said closure has been manipulated to effect removal of said closure from said container neck.,

BRTEF DESCRIPTION OF DRAWINGS

Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

S Fig, 1 shows a cross sectional elevation of a container neck and a corresponding closure according to a preferred embodiment of- the present invention;

Fig. 2 is an enlarged view of that portion of a cross sectional elevation of a container neck and a corresponding closure circled with dotted line and marked 'A' in Fig.1 showing a preferred embodiment of a container neck and corresponding closure; o Fig. 3 is an enlarged view of that portion of a cross sectional elevation of a container neck and a corresponding closure circled with dotted line arid marked 'A' in Fig.1 and showing another embodiment of the present invention co-operating sealing means between a closure 100 and a container neck, 200 ;

Fig. 4 is an enlarged view of that portion of a cross sectional elevation 5 of a container neck 200 and a corresponding closure 100 circled with dotted line and marked 'A' in Fig.l and showing yet another preferred relationship between cooperating sealing means on closurelOO and neck 200;

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 0

Fig. 1 shows a cross sectional elevation of a container neck 200 and a corresponding closure 100 said closure having an annular disc forming top wall 105 said top wall having outer or upper surface 105A and inner surface 105B and depending from said top wall 105 a skirt wall 110 said skirt wall 110 having an inner surface 111 and 5 thread means 1 12 projecting ftom said inner surface and an annular sealing projection • 130 which is formed to sealingly engage with corresponding container neck 200 and said container neck 200 having a neck wall 210 having an outer neck surface 216 and an inner neck surface 218 and thread means 215 projecting from said outer surface said thread means formed to co-operate with said thread means 112 of closure 100 to 0 threadingly engage and retain said closure 100 on said neck 200 and annular sealing projection and or sealing surface and or neck sealing ring 224 projecting from said

inner neck surface 218 towards the axis of said neok and said annular ring 224 formed to co-operate with said annular sealing projection 130 of said closure 100 to sealingly engage with said closure 100 upon application of said closure to said neck and said sealing ring 224 is formed by contact of a polyolefin material from which the container or at least the container neck is formed with a uniform surface of a moulding device which is shaped to form the orifice of said container neck ( not shown). Said uniform surface of said moulding device enabling the creation of a sealing surface on said container neck which is free from surface irregularities which would otherwise prevent proper sealing engagement between said container neck and said closure. Preferably said neck of said container is formed by extrusion Wow moulding and or injection blow moulding.

Fig. 2 is an enlarged view of that portion of a cross sectional elevation of a container neck 200 and a corresponding closure 100 circled with dotted line and marked 'A* in Fig. T and showing a preferred relationship between co-operating sealing means on closure 100 and neck 200 whereby said annular sealing projection 130 on closure 100 is preferably formed with an inner annular surface 134 located closer to the axis of the closure than outer annular surface 138 said outer annular surface 138 extending between areal38A and area 14OA whereby the diameter of said sealing projection 130 at area 140A is greater than the diameter at area 138A and adjoining and connected to said outer annular surface 138 is outer annular surface 140 extending between area 140A and area 140B and formed such that the diameter of said outer annular surface 140 is the same and forming a cylindrical surface parallel to the axis of said closure or if said diameters vary so as to form one or more annular sealing surfaces other than a cylindrical surface then such difference in diameters still allows for such interference required in fit to effect a sealing engagement between said annular sealing projection 130 and said container neck 200 and said annular sealing surface 140 having a length extending over a vertical height measured parallel to the axis of said closure and represented by the distance ⁴ C between dotted lines ^£ C1 ' and 'C2' . Said distance 'C being at least equal to the axial distance closure 100 moves relative to container neck 200 upon removal rotation of said closure 100 prior to operation of tamper evidence means (tamper evidence means not shown) such that

sufficient of said annular sealing surface 140 is in sealing engagement with said container neck 200 to keep the container sealed until tamper evidence means on said closure has operated to show that the container has been un-sealed and connected to said outer annular surface 140 is outer annular surface 145 forming annular channel 145 A said channel 145 A spaced apart from said inner surface 105B towards said outer surface 105 A ;

said container neck 200 having annular sealing surface 224 which is preferably spaced apart from inner neck surface 218 by a distance 'E' and said distance 'E' being such that annular surface 140 of closure 100 is spaced apart from and does not interfere with inner surface 218 and annular sealing surface 224 is preferably formed; at a diameter providing an interference fit with annular surface 140 of annular sealing projection 130 of closure 100 and such interference preferably being less than distance 'B' whereby upon removal rotation to remove said closure from said container neck said annular sealing surface 224 remains in sealing engagement with said annular surface 140 of closure 100 to seal the container, until tamper evidence means on said closure has operated to show thai the container has been un-sealed.

Fig. 3 is an enlarged view of that portion of a cross sectional elevation of a container neck 200 and a corresponding closure 100 circled with dotted Jitie arid marked 'A' in Fig.l and showing an alternate preferred relationship between co-operating sealing means on closure 100 and neck 200 to that relationship shown in Fig. 2 and whereby said annular sealing surface 224 on container neck 200 is formed with a curved shape such that sealing projection 130 on closure 100 makes annular sealing contact at the point on said annular sealing surface 224 which is closest to the axis of said container neck.

Fig, 4 is an enlarged view of that portion of a cross sectional elevation of a container neck 200 and a corresponding closure 100 circled with dotted line and marked 'A' in Fig.1 and showing yet another alternate preferred relationship between co-operating sealing means on closurelOO and neck 200 to that relationship shown in Fig. 2 and Fig, 3 and whereby said annular sealing surface 224 on container neck 200 is formed

with more than one curved shape such that sealing projection 130 on closure 100 makes sealing contact at more than one area viz. annular area 224A and annular area 224B on said annular sealing surface 224.

The various aspects of the present invention described above may be combined with any one or more of the following:

(i) Various child resistant features, such as is disclosed in Australian patent 43435/85 ( 550878 ) the disclosures of which are hereby incorporated in this application and one of said features may be of the type whereby it is necessary to exert downward force either on the top of the closure or on the top of an over-cap which fits over the top of the closure, such that the downward force overcomes resistance thereby allowing engagement means between the over-cap and the closure to enable removal rotation of the closure to operate the tamper-evident feature and remove the closure from the neck of the container, (ii) child-resistant tamper-evident closures, including a "squeeze dropper" type dispensing closure.

(iii) Dispensing closures for liquids, such as oils. (iv) Dispensing closures for particulate matters, such as granular powders and the like.

(v) The moulding of the closure from more than one type of material. For example, it would assist recycling if the closure tamper-evident band was moulded in the same material as the container. In another example a different colour or type of material may be used to mould the tamper band promoting visual difference between closure body and tamper band or physical performance of the tamper band.

(vi) Various dispensing means such as, but not limited to, a perforated or partially perforated closure with flip top cover, a flexible membrane with cruciform or other pattern slits or openings to thereby permit the dispensing of container contents or a pump action dispenser or a push/pull valve closing/opening feature.

(vii) A closure applied by axial rather than rotational motion and closures with more than one thread means,

(viii) A closure with a cooperating ratchet or engagement means between the tamper-evident band and features on the neck of the container such that cooperation between the said engagement means or any of them upon removal rotation of the threaded closure tends to promote severing of the frangible ribs connecting the tamper-evident band to the skirt of the closure. Said engagement means having ramped surfaces which cooperate during application of said closure to said container neck to reduce rotational force on the tamper-evident band during application reducing the possibility of severing the frangible ribs connecting the tamper-evident band to the skirt of the closure.

(ix) Various means of employing an additional foil seal to ensure freshness of the contents of a container and which may include a means to pierce the foil.

(x) Closures made of metal or plastic materials, or a combination of metal and plastic materials as may be useful in hot fill or retorted or vacuum seal packages.

(xi) Containers made of plastic, metal and glass materials. Although the various aspects of this invention have been described with reference to specific examples it will be appreciated by those skilled in the art that the invention may be embodied in many other forms.

Fig. 1 is as per Fig.1 of Australian provisional application No, 2006904829 filed September 4 ^th , 2006

Fig. 2 is as per Fig.2 of Australian provisional application No. 2006904829 filed September 4 ^th , 2006

Fig. 3 is as per Fig,3 of Australian provisional application No, 2006904829 filed September 4 ^th , 2006

Fig 4 is as per Fig.4 of Australian provisional application No. 2006904829 filed September 4 ^th 2006