Container closure

Abstract

The invention relates to a container closure (11) comprising: a pouring element (13) which is made of a plastics material and transitions into a container body (19a) or can be fastened to a container body (19b) and has a neck (21) having an upper and a lower end (23a, 23b) and having an external screw thread (25); and a fiber-based closure cap (15) for closing a pouring opening (17) provided within the pouring element (13). The closure cap (15) has a circular head plate (27) and a cylindrical threaded part (29) which surrounds the head plate (27) and has an open edge (31) and an internal thread (33). The internal thread (33) interacts with the external thread (25) of the pouring element (13). On the open edge (31) of the fiber-based closure cap (15), a first retaining element (41) is formed which interlockingly interacts with a second retaining element (41) formed on the pouring element (13).

Description

[0001] Container closure

[0002] Field of the invention

[0003] The invention relates to a container closure according to the preamble of claim 1.

[0004] State of the art

[0005] Fiber materials have gained new importance as packaging materials in recent years due to their particularly sustainable nature. Advances in wet forming technology for components with undercuts, such as containers and bottles, are opening up new fields of application. Other new technologies, such as the dry forming of fiber mats, are enabling new fiber-based bodies such as closures. These products compete with previously known products made primarily of plastic. One disadvantage of fiber-based closures is that the functionalities commonly found in plastic closures and taken for granted by consumers, such as a tamper-evident seal or a tamper-evident seal, have not yet been implemented.

[0006] Object of the invention

[0007] The disadvantages of the described prior art give rise to the task of creating a closure with a fiber-based closure cap which has a tamper-evident seal.

[0008] Description

[0009] The stated problem is solved in a container closure by the features stated in the characterizing portion of patent claim 1. Further developments and / or advantageous embodiments are the subject of the dependent patent claims.

[0010] The invention is preferably characterized in that a first retaining element is formed on the open edge of the fiber-based closure cap, which engages in a positive fit with a second retaining element formed on the pouring element. This allows the lower part of the closure cap to be permanently held to the pouring element when the closure cap is unscrewed for the first time. A tamper-evident seal can therefore be implemented in a manner similar to that used for plastic closure caps with a tamper-evident ring.

[0011] In a particularly preferred embodiment of the invention, a tamper-evident ring is formed on the closure cap, which is connected to the threaded part by a plurality of predetermined breaking ribs. The first opening of the container closure can be indicated by the breaking of the predetermined breaking ribs, and the open edge and the first retaining element are provided on the tamper-evident ring. Thus, the predetermined breaking ribs make it immediately apparent whether the closure is originally sealed or has already been opened.

[0012] It has proven useful to create the breakaway ribs by means of perforations running circumferentially along the threaded part, with the breakaway ribs serving as the separating sections between the perforations. The perforations can be easily created by horizontal cuts using a circular blade or a laser.

[0013] In another particularly preferred embodiment, the first retaining element is realized by a circumferential, outwardly curved rim on the open edge. The rim can be bent outward during the pressing process, in which a fiber mat is formed into the closure cap. The rim is pushed past the second retaining element when screwed onto the pouring element for the first time. When screwed on for the first time, the rim hooks onto the underside of the second retaining element.

[0014] The invention is also preferably characterized in that the second retaining element is implemented as a roof covering a circumferential groove formed at the lower end of the neck, wherein the groove is formed by the neck, a base, and an outer cylinder. The rim can be pushed past the roof covering during the initial screwing and can then be reliably locked to the underside of the roof covering. This allows the tamper-evident ring to be reliably held in the groove, and the predetermined breaking bars break before the tamper-evident ring can be pulled out of the groove by axial forces.

[0015] In another preferred embodiment, the rim is formed as a first circumferential barb. The first barb slides particularly easily past the canopy when the cap is first screwed on, as it can be bent radially inward. Once engaged in the groove, the barb permanently hooks onto the underside of the canopy.

[0016] The canopy is conveniently formed from a plurality of second barbs. The brim slides past these with little resistance when screwed on for the first time, as the second barbs can be folded radially outward. When a radial force is applied from below, such as when the cap is first unscrewed, the second barbs are pulled inward, thus holding the brim in place.

[0017] Conveniently, the rim is a first circumferential step. This preferably protrudes radially from the tamper-evident ring and preferably interacts with the second barbs. It is also conceivable that the first and second barbs are provided as retaining elements for a particularly stable connection.

[0018] It is advantageous if the canopy is a second, circumferential step. Such a second step, which can also be referred to as a cam, allows forced demolding from the injection mold in which the pouring element is cast, without the need for slots on the outer wall of the groove for demolding purposes.

[0019] The roof is advantageously formed from second steps with slots between them. The slots allow the pouring element to be demolded, even if the second steps are taller, since the steps can be moved outward during demolding.

[0020] In a further preferred embodiment of the invention, the second barbs are flaps that are angled inward. The flaps can be removed from the injection mold and provide a particularly stable, form-fitting hold for the brim. When screwed on for the first time, the flaps fold outward from the brim and then fold back into their normal position when the brim is below the flaps.

[0021] In a particularly preferred embodiment of the invention, the height of the closure cap from the inside of the head plate to the open rim is smaller than the height of the pouring element from the top of the neck to the top of the base. These height dimensions allow the tamper-evident ring to fall into the groove after the predetermined breaking bars have broken. As a result, after the closure is first opened, the tamper-evident ring is spaced from the bottom of the closure cap by a distance equal to the difference between the two heights defined above. It is therefore immediately and clearly recognizable when the closure has already been opened.

[0022] For convenience, the pouring element has a collar attached to the neck. This collar serves as an adhesive surface, allowing the pouring element to be glued to a composite beverage carton. The base of the groove can also be used as a collar if the pourer is to be attached to the beverage carton from the outside.

[0023] It is advantageous if the base part is the collar and the collar extends radially beyond the groove. The protruding part of the collar also allows the pouring element to be glued to a beverage carton from the inside.

[0024] Because the fiber-based closure cap is coated with a polymer at least on the inside of the head plate, it is protected from liquids. If the inner wall of the threaded part is also coated with a polymer, this has the advantage that the polymer coating increases rigidity in this area. The coating of the internal thread allows the maximum tightening torque of the closure to be increased. In addition, the friction surfaces, such as the thread, prevent fibers from being released from the surface due to the surfaces moving against each other, which would impair the function of the closure after repeated use.

[0025] To create a "cone sealer," the head plate features a shoulder that interacts with the upper end of the neck to form a seal. This allows the cap to reliably seal the pouring element, despite being fiber-based.

[0026] Further advantages and features will become apparent from the following description of three exemplary embodiments of the invention with reference to the schematic representations. They show, not to scale:

[0027] Figure 1: a first embodiment of a container closure in a side view and with a sectional view to the right of the rotation axis; Figure 2: a second embodiment of the container closure in a side view and with a sectional view to the right of the rotation axis and

[0028] Figure 3: a third embodiment of a container closure in a side view and with a sectional view to the right of the rotation axis.

[0029] Figures 1 to 3 show three different embodiments of a container closure, which is designated overall by the reference numeral 11. The container closure 11 has a plastic pouring element 13 and a fiber-based closure cap 15 for closing a pouring opening 17 provided within the pouring element 13.

[0030] The pouring element 11 merges into a container body 19a or can be attached to a container body 19b. The pouring element 13 comprises a neck 21 with an upper and lower end 23a, 23b and an external thread 25. The neck 21 preferably has the shape of a cylindrical shell, which defines the pouring opening 17. The pouring element is preferably injection-molded in a mold.

[0031] The closure cap 15 has a circular head plate 27 and a cylindrical threaded portion 29 surrounding the head plate 27, with an open edge 31 and an internal thread 33. The internal thread 33 cooperates with the external thread 25 of the pouring element 13.

[0032] A fiber-based closure cap 11, as used in this application, is understood to mean that the closure cap is produced by dry forming fiber mats, by heating the fiber mat and pressing it in a mold so that the fiber mat takes on the shape of the closure cap. To make the closure cap 15 watertight, at least the inside of the head plate 27 is coated, preferably with a polymer. It is preferred if the inside of the threaded portion 29 is also polymer-coated.

[0033] A tamper-evident ring 35 is formed on the closure cap 15, which is connected to the threaded portion 29 by a plurality of predetermined breaking ribs 37, wherein the initial opening of the container closure 11 can be indicated by the breaking of the predetermined breaking ribs 37. The tamper-evident ring 35 or the predetermined breaking ribs 37 can be easily manufactured by providing perforations 39 in the circumferential direction on the threaded portion 29. These perforations 39 can be created by cutting with a laser or a circular knife. The predetermined breaking ribs 37 are the separating sections between the perforations 39. The tamper-evident ring 35 is thus created by cutting the perforations 39.

[0034] A first retaining element 41 is formed on the open edge 31 of the fiber-based closure cap 15, which cooperates in a form-fitting manner with a second retaining element 43 formed on the pouring element 13. The open edge 31 and the first retaining element 41 are provided on the guarantee ring 35. The first retaining element 41 can preferably be formed as a first step 41a or as a first barb 41b.

[0035] When the closure cap 15 is opened for the first time, the first and second retaining elements 41, 43 interlock, thereby holding the guarantee ring 35 to the pouring element 13. As a result, the predetermined breaking ribs 37 break when the closure cap 15 is unscrewed for the first time, and the guarantee ring 35 remains on the pouring element 13. When the closure cap 15 is screwed back on, the predetermined breaking ribs 37 are broken, and the vertical distance between the threaded portion 29 and the guarantee ring 35 is increased. This immediately indicates that the container closure 11 has been opened for the first time.

[0036] The first retaining element can be realized as a circumferential, outwardly bent rim 41 or as a "hat rim" on the open edge 31. The rim 41 can be produced during the pressing process of the closure cap. The rim cannot be bent inward during the pressing process, and an inwardly bent rim cannot be demolded. The rim can be formed as a first circumferential step 41a at an angle of 90 degrees to the threaded part 29 (Figures 1 and 2). The rim can also be bent further upwards to form a first barb 41b at an angle of between 120 and 170 degrees to the threaded part (Figure 3).

[0037] The second holding element can be implemented as a roof 43 of a circumferential groove 45 formed at the lower end 23b of the neck 21. The groove 45 is formed by the neck 21, a base 47, and an outer cylinder 49. The roof 43 can be shaped as a second circumferential step 43a or a cam (Figure 1) and can be forcibly removed from the injection mold. If the step height is increased to ensure a particularly secure hold of the guarantee ring 35, slots 51 must be provided on the outer cylinder 49 so that the pouring element 13 can be removed from the injection mold (Figure 3). The roof can also be implemented as second barbs 43b. So that the second barbs can be removed from the injection mold, they are implemented as a plurality of flaps 43b that are angled inwards (Figure 2). How the step 41a interacts with the second barbs 43b is shown in Figure 2.A combination of the first barb 41b with the steps 43a is illustrated in Figure 3. Other combinations of the first and second retaining elements 41, 43 are also possible. It is essential that the tamper-evident ring 35 is reliably held in the groove 45 during initial opening and that the predetermined breaking webs 37 break safely.

[0038] The height 53 of the closure cap 15 from the inside of the head plate 27 to the open edge 31 is smaller than the height 55 of the pouring element 13 from the upper end 23a of the neck 21 to the top of the base 47. This allows the tamper-evident ring 35 to fall into the groove 45 after the initial opening until it rests on the base 47. As a result, when the closure cap 15 is screwed on again, a gap is created between the upper edge of the tamper-evident ring and the lower edge of the threaded portion, which gap corresponds to the difference between the two heights defined above. This makes it immediately apparent that the container closure 11 has already been opened.

[0039] The base 47 corresponds to a collar 57 or is part of a collar 57 that projects beyond the base. The projecting part can function as a connecting surface 59. The upper side of the connecting surface 59 can then be connected, in particular glued, to the inside of a composite beverage carton 19b. Accordingly, the container closure 11 can be used as a closure for a composite beverage carton 19b.

[0040] The fiber-based closure cap 15 can also be formed as a so-called "cone sealer." For this purpose, the shoulder 61 on the head plate can be pressed during the pressing process of the fiber mat. The shoulder 61 is intended to interact sealingly with the upper end 23a of the neck 21.

[0041] The present container closure 11 makes it possible to provide a tamper evident seal for a fiber-based closure cap 15. Legend:

[0042] 11 Container closure

[0043] 13 Pouring element

[0044] 15 Fiber-based cap

[0045] 17 Pouring opening

[0046] 19a, 19b Container body, composite beverage carton

[0047] 21 Neck

[0048] 23a, 23b Upper and lower ends

[0049] 25 external thread

[0050] 27 Headstock

[0051] 29 Threaded part

[0052] 31 Open edge of the threaded part

[0053] 33 internal thread

[0054] 35 Guarantee ring

[0055] 37 predetermined breaking bars

[0056] 39 perforations

[0057] 41 First holding element, circumferential brim.

[0058] 41a, 41b First stage, first barb

[0059] 43 Second holding element, roofing

[0060] 43a, 43b Second stage, second barb, flared flaps

[0061] 45 Circumferential groove

[0062] 47 Bottom of the groove

[0063] 49 Outer cylinder

[0064] 51 slots

[0065] 53 Height of the cap

[0066] 55 Height of the pouring element

[0067] 57 collar

[0068] 59 connecting surface

[0069] 61 paragraph

Claims

1. Container closure (11) comprising a pouring element (13) made of plastic, which merges into a container body (19a) or can be fastened to a container body (19b) and comprises a neck (21) with an upper and lower end (23a, 23b) and an external thread (25), and a fiber-based closure cap (15) for closing a pouring opening (17) provided within the pouring element (13), the closure cap (15) comprising a circular head plate (27) and a cylindrical threaded part (29) surrounding the head plate (27) with an open edge (31) and an internal thread (33), which cooperates with the external thread (25) of the pouring element (13), characterized in that a first holding element (41) is formed on the open edge (31) of the fiber-based closure cap (15), which holding element can be positively connected to a second holding element (41) formed on the pouring element (13).

2. Container closure according to claim 1, characterized in that a guarantee ring (35) is formed on the closure cap, which is connected to the threaded part (29) by a plurality of predetermined breaking webs (37), wherein the first opening of the container closure (11) can be indicated by breaking of the predetermined breaking webs (37) and the open edge (31) and the first holding element (41) are provided on the guarantee ring (35).

3. Container closure according to claim 2, characterized in that the predetermined breaking webs (37) are provided by perforations (39) running in the circumferential direction on the threaded part (29), whereby the predetermined breaking webs (37) are the separating sections between the perforations (39).

4. Container closure according to claim 1 or 2, characterized in that the first holding element is realized by a circumferential outwardly bent rim (41) on the open edge (31).

5. Container closure according to one of the preceding claims, characterized in that the second holding element is realized as a roof (43) of a circumferential groove (45) formed at the lower end (23b) of the neck (21), wherein the groove (45) is formed by the neck (21), a base (47) and an outer cylinder (49).

6. Container closure according to one of claims 4 or 5, characterized in that the rim (41) is formed as a first circumferential barb (41b).

7. Container closure according to claim 5, characterized in that the roof (43) is formed from a plurality of second barbs (43b).

8. Container closure according to one of claims 4, 5 or 7, characterized in that the rim (41) is a first circumferential step (41a).

9. Container closure according to one of claims 5, 6 or 8, characterized in that the roof (43) is a second circumferential step (43a).

10. Container closure according to one of claims 5, 6 or 8, characterized in that the roof is formed from second steps (43a) between which slots (51) are provided.

11. Container closure according to claim 7, characterized in that the second barbs are flaps (43b) which are inclined inwards.

12. Container closure according to one of claims 5 to 11, characterized in that the height of the closure cap (15) from the inside of the head plate (27) to the open edge (31) is smaller than the height of the pouring element (13) from the upper end (23a) of the neck (21) to the top of the base (47).

13. Container closure according to one of the preceding claims, characterized in that the pouring element (13) has a collar (57) adjoining the neck (21).

14. Container closure according to one of claims 5 to 13, characterized in that the base (47) is part of the collar (57) and the collar (57) projects beyond the groove (45) in the radial direction.

15. Container closure according to one of the preceding claims, characterized in that the fiber-based closure cap (15) is coated with a polymer at least on the inside of the head plate (27).

16. Container closure according to one of the preceding claims, characterized in that to realize a «cone sealer» the head plate (27) has a shoulder (61) which cooperates sealingly with the upper end (23a) of the neck (21).

17. Use of the container closure (11) as a closure of a beverage carton (19b).

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