CONTAINER CLOSURES

Abstract: Various container closures are made from one or more planar members so as to be substantially flat against the container, e.g. carton, wall. Separately formed closures (10) generally comprise first (16) and second members (20), one of which is pivotable with respect to the carton (12) to replace a plug (22) in a hole (28) in the carton or the second member.

Description: CONTAINER CLOSURES This invention relates to a re-closable closure device for use on containers. The closure of the invention has been designed for application to cartons for use in liαuiα packaging, but is suitable for use with all kinds of containers including πgiα or flexible plastics, for a variety of materials including powαers and granules as well as liαuids. Cartons used for packaging liquids are well known, for example cartons for containing milk, fruit juice and the like. Such cartons are generally made from a one-piece blank of carton board, coated on both sides with polyethylene The canon blank is folded to close the bottom and to provide either a slant top. a flat top or an upstanding (gable) too and. after filling, the carton is hermetically sealed. To open the carton, the top is usually folded back and opened out to proviαe a pouring spout. The carton can be re-closed by folding the pouring spout back in again This known method of opening and re-closing a carton is not wholly satisfactory Sometimes it is difficult to open the top to provide a pouring spout, and liquid is easily- spilled during the opening operation. It is also known to provide one-use only closures in the top of cartons For example, a hole is formed in the carton and covered with a simple plastic film closure, which can be penetrated by a straw or otherwise pulled off However, these once-only use closures are not re-closeabie and they are not well designed for pouring. Separately attachable closures are also known for cartons and these can have the advantage of allowing the carton to be re-closed after opening to maintain the freshness of the contents, without the need for tearing or folding the carton. There is nowadays a need in the industry to provide tamper-evident closures. With separately attachable closures, tamper evident features need to be incorporated in the design. For example, pouring fitments for paperboard cartons have been manufactured from plastics materials using injection moulding techniques. Such fitments generally have to be applied to the carton at the time of filling it with liquiα However, the material, manufacturing and aoplication costs of suen fitments are expensive and. in addition, the fitments give stacking problems For example, various different designs of screw cap have been applied to cartons, but such caps are too high and interfere with the stacking and general handling of the carton and the blank. US Patent No 4 934 59Θ describes a separately attachable plastics closure for a carton To open the carton, a rigid lever is pushed downward and rotates nearly 180° By pivoting the lever, a portion of the lever penetrates a scored area of the canon and eventually, another poπion of the lever seats over the opening of the carton to provide a pouring spout A removable cover is then positioned over the ODening, so that re-opening and re-closing of the carton occurs by removing the cover However, the material, manufacturing and application costs of this closure device are high when compared to the standard price of a carton without a fitment and. although this fitment can be flatter than a protruding screw cap. it still provides a rigid upstanding protrusion which can interfere with the general hanαling of the carton Thus, there is still a need for a satisfactory re-closable closure device which can lie substantially flat in closed position on the container without upstanαing significantly from the container surface. In the case of closures for cartons, it is desirable to provide a carton closure wnich can be attacheα to a flat carton blank preferably by the carton manufacturer so that the canon can be assembled and filled by the carton customer using his existing macninery with minimal modifications to the machinery One asDect of the present invention provides a sealed container, such as a canon, having a re-ciosaole device including a plug received in a recess and a generally planar memoer which is pivotable with resϋect to the container to remove the plug from the recess and break the seal The plug may seat in the opening to close it. but it may be lifted clear by rotating the film member about its hinged region Such an arrangement (in closed condition) can lie flat on the container sun ' ace and extend only a millimetre or two above the surface. The seal is preferaoly a hermetic seal so that the container can contain peπsnable product such as miik The plug may be a snap fit in the recess. Althougn the reDiacement of the plug in the recess will not reseal the container it will prevent the ingress of dust and help to minimise spillage should the container be knockeα over The recess wnicn receives the plug may comDπse a hole in the wall of the container, in wnicn case the plug may comprise a portion of the container wall. The plug may De weakly joineα to the container wail, for example via a score line, to form the seal, and thus when the plug is removed the seal is broken but the plug can still be reDlaced. Alternatively or additionally, the container may be seaieα by means of a film covering a hole in the container wail, a portion of whicn is attacneα to the plug to be removed on lifting the plug to reveal the hole. In an alternative emDodiment of container according to the invention, the closure comprises two generally planar members, one of which covers a hole in the container and may provide the recess for receiving the plug, and the other of which is pivotable to replace or remove the plug. Thus, another aspect of the invention provides a container closure comprising first and seconα generally planar members, in wnich the first member covers a hole in the container in use and the second memDer is pivotable with respect to the container to return or remove a plug to or from the hole. In one emboαiment of the invention illustrated in Figure 1 below, the first member is laminated to the seconα member and the plug is attached to the first member. Thus, the whole closure may be pivotable with respect to the container. In another arrangement, the second member is pivotable with resDect to the first. Thus, the first memDer may be secured to the container to cover the hole. The closure device may be bonded to the container on one side only of the hole, or on two or more sides of the hole. Many suitable methods for attaching the closure device to the container will be known in the art. For example, the closure αevice of the invention may be bonded to the container either by using adhesives or Dy ultrasonically welding the closure device to the container. The first memDer may comprise a pouring lip arranged to extend over an edge ofthe container Thus liquid is directed over the edge of the container and not down the face of the container on pouring, and the lip cleanly cuts off the flow of liquiα wren returning the container to the upright position. The lip preferably ovemangs an eαge of the container by at least 1mm The first memoer may be made of a thin resilient material such as polyethylene tape or foil which, being flexiDle springs back after being pushed or taped down. For the separately attachable closure devices known in the art. which are made of rigid mateπal. this amount of overhang is generally unacceptable, on the ground that it catches on the filling machine and/or interferes with other containers during subsequent packaging operations. However, a film member made of a thin resilient material acts successfully as a pouπng lip with, for example, a 1mm overhang without being unduly obtrusive Such a material may be applied to the container blank or sleeve at fast speed by label-type applicators. The seconα memDer may comprise the plug. Alternatively the plug may be attached to the second member. Either way, the plug may be generally planar The first memoer may define a recess for receiving the plug. The piug may be weakly connecteα to the first memoer to form a seal. The plug may be a snap fit in the recess The first memDer may define a channel for receiving the second memoer. The second member may be received in the channel as a snap fit. for example by undercutting part or ail of the edges of the channel. It is possible to provide some means of directing liquid out of the recess or hole ana containing the liquid from spreading across the container as it comes out of the container. For example, the container can be embossed as a means of flow control. Thin ridges or grooved channels give some side control to liquid flow. Alternatively, the closure device may have sidewalls. which must of course be sufficiently low in height to ensure that they do not interfere with container stacking. It is less important to provide means for preventing the liquid from spreading across the toD of slant top (gable) cartons. For flat top cartons, sidewalls of at least 1mm nigh are Dreferred. The side wails may fold flat. For example, the side wails may fold inwardly towards each other over the pivotable member. This feature could be used to provide tamper evidence. The sidewalls could be incorporated in the first generally planar memoer. The present invention provides a closure device which, in closed condition, is substantially flat in appearance, and which thus does not interfere with the stacKing of cartons or blanks or other containers during production, or with their presentation in suDermarkets etc. For example, the height of a closure device of the present invention (in closed condition) may be 2mm or less. Also. the closure device of the invention can be produced and applied to cartons or other containers at a low cost. Previously, separately attachable plastics closures have had to be applied to cartons on the filling machine, involving large capital investments in applicator costs for each individual customer: whereas the thin closure device of the present invention can also be attached to the carton blank, eliminating any major capital investment for carton customers. The present invention also provides a carton or carton blank or other container having the above-described closure device applied thereto, so as to open and close an aperture formed in a wall of the container. A carton may be made from any suitable sheet material suen as. for example, carton board coated on both sides with a plastics material such as polyethylene, or from unprinted fibre board. The aperture formed in the container can be of any shape, but is preferably pear-shaDeα. whicn shape has been found to be very effective for pouring. When the aperture is pear-shaped, the width of the widest part of the pear snape controls the flow rate, and the narrowest part reduces "glugging". Suitably, the pear-shapeα aperture is about 20mm long, with a radius of about Smm at its widest part and of about 3mm at its narrowest part (but these dimensions are merely examples, and other size apertures can be used). "Glugging" can be eliminated by providing a vent feature or hole in the container, if glugging is perceived to be a problem. The aperture in the carton can be cut in any position which suits the attachment of the closure αevice and pouring of the container contents. The closure device may also include a tamper-evident feature if desired, to indicate when the initially closed device has been opened for the first time. In one advantageous embodiment of container or closure according to the invention. the planar member which is pivotable with respect to the container includes finger grip means. This preferably comprises a further planar member which is pivotably attached to the pivotable planar member. This further member may be weakly secured to the closure or container to provide tamper evidence. Any of the planar members described above may be in the form of thin films. Another aspect of the invention provides a method of assembling a flat walled carton including cutting a flat carton blank having an access hole, and securing a separately formed closure over the access hole with the blank in the flat configuration. Thus, the cartons can be filled and sealed in the usual way without the need for any modifications to current machinery. However, it may be that slightly modified magazines wiil be required to handle stacks of cartons according to the invention. Two edges of the carton blanks are usually sealed together to form a flat sleeve, before supplying to customers. This can be carried out either before or after the application of the closures. Once on site, the cartons are erected using existing machinery, one end is sealed, the cartons are filled and then their tops are sealed. In order that the invention may be more fully understood, embodiments thereof wiil now be described, by way of example only, with reference to the accompanying drawings, wherein: Figure 1 illustrates a first embodiment of closure device in accordance with the present invention: Figure 2 illustrates a second embodiment of closure device in accordance with the Dresent invention: Figure 3 is a Dian view of the second embodiment of closure device illustrated in Figure 2: Figure 4 illustrates a carton having a third embodiment of a closure device of the present invention appiied to its top face: Figure 5 is a piaπ view of the third embodiment of closure device illustrated in Figure 4: and Figures 6 (a) to (f) are various views of a further closure according to the invention. (a) being a Dian view of the closure in its closed configuration, (b) a side elevation of the closed closure fc) a plan view of the closure with the pull tab released (d) a side elevation of the closure partially open. Xe) a plan view of the closure fully open and (f) an end elevation viewed along arrow A in Figure 6 (e) Referring firstly to Figure 1. a closure device 10 is shown on a carton 12 which has a gable top 14. A first plastics film 16 is adhered to the carton 12 and provides a pouring lip 18. A second plastics film 20 carries a thin plug 22. The plug shown in Figure 1 is comprised of a square-shaped plate portion 24 and a protruding portion 26 of the same shape as a pouring aperture 28 cut in the carton 12. The portion 26 of plug 22 must then be of the same shape, so as to fit into the aperture to close it. A "click shut" effect is achieved as portion 26 of plug 22 penetrates the carton apeπure 28 to thereby re-close the carton after first opening. The carton must always be hermetically sealed until the first opening of the re-openable closure device. This may be achieved by having a membrane between the plug 22 and pouring apeπure 28. Alternatively the membrane may be inside the carton and may have a portion adhered to the plug portion 26 to be pulled through the pouring aperture and break away from the remainder on the first opening. The first plastics film 16 mav be a thin polyethylene or foil tape or a slightly more rigid layer or thin sheet. This may also be shaped to give some side control to liquid flow (not shown). The plastics film 16 may be bonded to the carton, for example, with adhesives or by ultrasonic welding. The second plastics film 20 may also be a thin polyethylene or foil tape, and the piug 22 may ce made of a thin layer of plastic. As wiil be understood with reference to Figure 1. the film 20 may be pulled up. so that it rotates about a hinge region 34. to thereby pull portion 26 of plug 22 out of the aperture 28 to open the carton 12. The tape 20 may then be lowered so that poπion 25 of piug 22 clicks into the aperture 28 so as to re-close the carton 12. When the film 20 is rotated to a vertical position (as shown in Figure 1 ), the Iower edge 36 of the piug 22 can rest against the carton 12 and the plug 22 thus remains substantially upright with the aperture open for pouring. With reference to Figure 2. a second embodiment of closure device 40 is shown on a flat top carton 42. A first plastics film 44 is adhered to the carton 42. so as to cover an aperture in the carton 42. and provides an aperture 56 and a pouring lip 46 to direct liquid from aperture 56 over the edge 48 of the carton 42. A second plastics film 50 carries the piug and is positioned over film 44 in the closeα configuration, overhanging the carton edge. Both plastics films 44.50 may be of foil or polyethylene. A thin relatively rigid plastics square 55 is bonded onto the outside of plastics film 50. The plastics square is cut so as to provide a middle region, which forms the opening piug 52. and two side panels 60. A "click shut" effect can be achieved by under-cutting the edges of side panels 60 (thereby providing a corresponding angle on the sides of the walls of plug 52). As with the first-described embodiment, the foil or polyethylene film 50 is pulled up so that it rotates about a hinge region 54, carrying the plug 52 with it. so that the plug 52 no longer covers the pouring aperture 56. The wails of the side panels 60 provide some side control to liquid flow. As an alternative the arrangement described above the rigid plastics square could be sandwiched between films 44 and 50. as shown in Figure 3 in - J ^ 206 plan view. Figure 3 shows the plug 52 in its closed condition. The piug 52 may then be lifted clear of the aDerture 56 by rotating film 50 about its hinged region 54 When the closure device 40 is in- its closed condition, the foil or polyethylene fiim 50 may be folded back and bonded weakly to the top surface of piug 52 or film 50 This Dond then breaks when film 50 is pulled UD to rotate about its hinge region 54 For example, double sided taDe 51 may be used to attach the film 50 to the top suπ ' ace of the plug 52. wnen the plug is in its closed position. This may proviαe a degree of tamper-evioence. In orαer to hermetically seal the carton, the film 44 may include a tear away portion in the shape of a hole 56 which is lifted with the piug 52 at the first opening of the carton to ODen the aperture 56. Referring to Figure 4. a flat top carton 72 is shown, having a third embodiment of closure device 70 bonded to its top face. Plastics film 74 is adhered to the top of the carton 72 and provides a pouring aperture and lip 76. The second plastics or coated paper film 78 carries the plug 80 which may be cut out from the first film 74 The entire closure device may be made of a thin plastic, coated Daper. or foil. As the film 78 is pulled up so that it rotates about hinge region 82. it carries plug 80 with it. so that plug 80 is moved from its closed position, in which the aperture is closed, to an open position in which the aperture is open for pouring. Sidewalls 84 are Drovided to contain the liquid from spreading across the carton. The side walls fold over towards each other to hold down piastics film 78 so as to re-close the carton. Figure 5 shows this closure device in plan view, and like parts are designated the same numpers The closure device 70 is shown in its closed condition. If the closure αevice 70 was to overlie an aperture in a carton, the piug 80 (see Figure 4) would be seated over the aperture to close it. and would be lifted clear by lifting film member 78 and rotating it about its hinged region 82. Sidewalls 84 fold inwardly towards each other so as to hold down plastics film 78 which carries the plug, when the closure device is in its closed condition. When film member 78 is lifted and rotated about its hinged region 82. the sidewalls 84 no icr-ger fold flat, but are moved to be upstanding so as to provide sidewalls 84 of. for example, at least 1mm high. The sidewalls 84 prevent liquid from SDreading across the top of a carton during pouring. Whilst the foregoing is described as an arrangement of two separate films 74. 78. plus separate sidewalls. the closure device could be cut out of a web of material as a singie piece, that is to say, material is cut and creased on a rotary cutter, then suDsequently formed into a design with sidewalls which fold flat. For example, side wail portions 84 can be folded inwardly from the edges of base film 74 and film member 78 could be formed as an extending tab from the same piece of film. It may also have an inner polyethylene patch and/or a tamper pull tab (not shown). As an alternative to the above embodiments of the invention. it would be possible to stamp into the carton blank the outline of a removable plug, but without puncturing the inner polyethylene layer, which would then remain as a hermetic seal. To open the carton, a plastics film bonded to the plug could be lifted to pull the plug out of the pouring aperture of the carton, with the weak inner layer of polyethylene tearing as the plug is removed. The plastics film carrying the plug may then be lowered so that the plug clicks into the aperture so as to re-close the caπon. This feature could be incorporated in any of the embodiments of the invention described above. Figure 6 illustrates a further closure device according to this invention. This closure device 100 is again designed to be secured over a hole in a carton. The device generally comprises three planar members which overlie each other in the dosed configuration, namely a base member 101 which lies against the carton surface in use. a lid member 102 which is pivotable with respect to the base member to open or close the closure, and a handle or tab member 103 which is pivotable with respect to the lid member 102 and is used for lifting the lid member 102. Each of the three members 101. 102. 103 is in the form of a relatively rigid plastics film or thin sheet. The closure may be injection moulded as one piece, preferably in the open flat configuration shown in Figure 6 (e). The base member 101 includes a lip portion 105 wnich typically overhangs the carton eαge in use to Drovide a pouring lip. A slightly thicker central region 106 includes a central plug portion 107. The outline of the plug portion 107 is a weaK moulded break line so that it is weakly attached to the remainder of the central portion 106 Finally the base member 101 includes thicker side regions 108 " 39 wnich define a channel for receiving the lid memDer 102. As shown in Figure 6 ff) the edges of regions 108. 109 are slightly undercut and the lid member 102 is likewise snaped. at least at ends remote from the pivot eαge. so that the lid memDer 102 is received between regions 108. 109 as a snaσ fit (The same edge cutting feature can be used to achieve a " click-shut effect in the foregoing embodiments of the invention) The lid memDer 102 is moulded as a flat sheet weakly attached to the base member 101 so as to be pivotable with respect to the base member. A slight circular indentation 115 may be provided to facilitate gripping the handle member 103 The portion adjacent the hinge axis may be slightly narrowed so that only the forward eαges snap fit in the base member. The handle member 103 is generally planar and includes a ring portion for manual gripping The arcuate region remote from the pivot eαge may σe slightly thicker Side tabs 116. 117 overnang the side regions 108 109 of the base. After moulding the completed closure 100 is folded concertina-wise with the lid portion 102 overlying the base member 101 and the handle member 103 folded back over the lid member 102. The lid member is then attached to the plug portion 107 of the base member, for example by heat staking. The tabs 116. 117 of the handle member 103 are attached to side regions 108. 109. again preferably by heat staking. The attachment of the side tabs 116. 117 to the base portion 101 is an optional feature mainly intended to provide tamper evidence but also useful for ensuring that the closure remains flat during handling. The closure is now ready for application to a carton. The carton is provided with a hole ano the closure is secured over it. for example by adhesive. This operation may be carried out with the carton still in its flat configuration, either as an ODen blanκ or a folded sleeve. Once the closure has been secured to the carton the carton can be assembled and filled in the usual way, without the need for additional eαuipment. In fact, all of the closures described above are suitable for application to a flat carton blank to avoid the need for any modifications to existing liquid packaging eαuipment. The closure is opened as follows: The ring portion of the handle portion 103 is lifted to break the tabs away from the side regions 107. 108. and then lifted further to pivot lid portion 102 anti-clockwise as shown in Figure 6 (d). The attachment of the plug portion 107 to lid portion 102 is made sufficiently strong that the plug poπion becomes detached from base poπion 101 and stays attacned to lid poπion 102. as indicated by dotted lines in Figure 6 (e). The hermetic seal of the canon is now broken, but the closure can be reclosed by replacing the lid portion over the base portion. The preferred material for this closure is a plastics material such as polypropylene or meαium density polyethylene although other materials may prove suitable. It wiil be appreciated that the third planar member 103 could be emitted and the memDer 102 could simply be lifted with a fingernail. Tamper evidence, if required, could then be built in by suitable modifications to member 102. All ofthe emDodiments of the invention described above are suitable for use with flat topped or "gable " toDped or slant topped cartons.

Claims: Claims 1. A sealed container having a re-closable device closure including a plug received in a recess and a generally planar member which is pivotable with respect to the container to remove the piug from the recess and break the seal. 2. A container as claimeα in claim 1 in which the plug is a snaσ fit in the recess. 3. A container as claimed in claim 1 or 2 in which the recess is a hole in the wall of the container. 4. A container as claimed in claim 3 in which the piug comprises a poπion of the container wall. 5. A container as claimed in claim 4 in which the plug is weakly joined to the container wall. 6. A container as claimed in any preceding claim which is sealed by means of a film covering a hole in the carton wall, a portion of which is attached to the plug to be removeα on rating the piug to reveal the hole. 7. A container closure comprising first and second generally planar members, in which the first member is designed to surround a hole in the container and the second memoer is pivotable with respect to the container to return or remove a plug to or from the hole. 8. A container closure as claimed in claim 7 in which the first member is laminated to the seconα memoer and the plug is attached to the first member. 9. A container closure as claimed in claim 7 in which second member is pivotable with respect to the first. 10. A container closure as claimed in claim 9 in which the first member provides a pouring lip arranged to extend over an edge of the container. 11. A container closure as daimed in claim 9 or 10 in which the plug is attached to the second member. 12. A container closure as claimed in claim 9 or 10 in which the second member comprises the plug. 13. A container closure as claimed in claim 9, 10. 11 or 12 in which the first member defines a recess for receiving the piug. 14. A container closure as claimed in claim 13 in which the plug is weakly connected to the first member to form a hermetic seal. 15. A container closure as claimed in claim 13 or 14 in which the plug is a snap fit in the recess. 16. A container as claimed in claim 13. 14. or 15 in which the edges of the piug and/or recess are at least partially undercut whereby the piug fits into the recess as a snap fit. 17. A container closure as claimed in any of claims 7 to 16 in which the first member defines a channel for receiving the second member. 18. A container closure as claimed in claim 17 in which the second member is received in the channel as a snaσ fit. 19. A container closure as claimed in claims 17 or 18 in which the sides of the channel are at least partially undercut whereby to receive the second member as a snap fit. 20. A container closure as claimed in claim 17. 18 or 19 in which the edges of the second member are at least partially undercut. 21. A carton closure as claimeα in any of claims 7 to 20 having an overall thickness of no more than 10mm. 22. A carton closure as claimeα in any of claims 7 to 21 having an overall thickness of no more than 5mm. 23. A carton closure as claimeα in any of claims 7 to 22 having an overall thickness of no more than 3mm. 24. A container closure as claimed in any of claims 7 to 23 having an overall thickness of no more than 2mm. 25. A carton closure as claimed in any of claims 7 to 24 having tamper evident means 26. A container as claimed in any of claims 1 to 6 or a container closure as claimed in any of claims 7 to 19 in which the generally planar member which is pivotable with respect to the container includes finger grip means. 27. A container or carton closure as claimed in claim 26 in which the finger grip means are formed from a further generally planar member. 28. A container or container closure as claimed in claim 27 in which the further member is pivotable with respect to the planar member to which it is attached. 29. A container or container closure as claimed in ciaim 28 in which the further member overlies the planar member to which it is attached. 30. A container or container closure as claimed in claim 28 or 29 in which the further member is weakly secured to the remainder of the closure or the container. 31. A container provided with a closure as claimed in any of claims 7 to 30. 32. A method of assembling a flat walled carton including cutting a flat carton blank, and securing a separately formed closure over " the access hole with the blank in the flat configuration. 33. A method as claimed in claim 32 further comprising the steps of defining an access hole in the carton blank. 34. A method as claimed in ciaim 33 further comprising scoring the outline of the access hole in the carton blank. 35. A method as claimed in claim 34 in which the carton is formed of mateπai coated with a waterproof layer and said scoring penetrates all but the waterproof layer. 36. A method as claimed in claim 33 in which the access hole is completely cut out of the carton blank. 37. A method as claimed in any claims 32 to 36 further comprising the step of sealing two edges of the blank together to form a sleeve, either before or after the application of the closure. 38. A method of packaging a fluid material in a flat walled carton including the method of any of claims 32 to 37 and further comprising the step of erecting the sleeve and sealing the iower end. filling the carton with the material and sealing the upper end.

Inventors: HALL JAMES, MICHAEL MICHAEL JAMES, HALL, JAMES, MICHAEL, MICHAEL, JAMES
Applicants: HALL JAMES, MICHAEL MICHAEL JAMES, REXAM PKL LIMITED, HALL, JAMES, MICHAEL, MICHAEL, JAMES
Application year: 1996
Main classification: B65D5
IPC codes: B65D5