LID FOR A BEVERAGE CAN OR SIMILAR

Abstract

The invention relates to a lid for a beverage can or similar, having a lid surface and a closure unit which is to be opened and is re-closable, which is disposed in the region of the lid surface. The closure unit has the property of selectively uncovering or closing a drinking opening in the lid surface. On the outer side of the lid a foil which, on the outer side of the lid, covers the closure unit and, around the closure unit, is entirely connected to the lid surface so as to be tight in such a manner that, on account of the connection between the foil and the lid surface, ingress of moisture is prevented or at least substantially prevented, is disposed.

Description

The invention relates to a lid for a beverage can or similar, having a lid surface and a closure unit which is to be opened and is re-closable, which is disposed in the region of the lid surface, and which selectively uncovers or closes a drinking opening in the lid surface.

The lid, in the use state, has an inner side pointing to the inside of the can and an outer side pointing to the environment.

Lids of this type are known from DE 10 2010 027 821, for example. Lids of this type for re-closable beverage cans are used, for example, for beverage cans which are in two parts and are known per se, consisting of a can body which is in one part and lid which is connected thereto. The can body here is typically shaped from aluminium or tinplate (steel), and on a longitudinal side initially includes an opening into which a beverage, for example, is filled at the bottling plant. After filling, the can body is closed by means of a lid, wherein typically the lid is connected in a tight manner to the can body by means of a double fold. In the case of conventional beverage cans which are not re-closable, the lid in most cases is entirely composed of aluminium. A lid of this type typically has a centrally disposed lid surface which, in the vicinity of the connection to the can body, is surrounded by a reinforcement bead. Typically, a drinking opening is provided in the lid surface, which drinking opening, in the case of conventional lids, is defined by a lid portion which can be torn open. As is known, a beverage can of this type is opened in that a weakening line, which defines the lid portion which can be torn open, is torn open by means of a grip tab, and the lid portion that can be torn open is simultaneously removed or bent so as to be out of the way. Beverage cans having lids of this type cannot be re-closed after having been initially opened.

In order to be able to re-close a beverage can after having been initially opened, cans having re-closable lids are known. Corresponding closure elements are described in DE 10 2010 027 821 cited above or also in WO 2005/068312, for example.

The invention is based on the object of improving beverage cans of this type.

According to the invention, this object is achieved by a lid for a beverage can or similar, having a lid surface and a closure unit which is to be opened and is re-closable, which is disposed in the region of the lid surface. The closure unit has the property of selectively uncovering or closing a drinking opening in the lid surface. In the use state of the lid, a side pointing to the inside of the can is the inner side of said lid, and a side pointing to the environment is the outer side of said lid. According to the invention, on the outer side of the lid a foil which, on the outer side of the lid, covers the closure unit and, around the closure unit, is entirely connected to the lid surface so as to be tight in such a manner that, on account of the connection between the foil and the lid surface, ingress of moisture is prevented or at least substantially prevented. This is relevant in order to ensure a hygienic environment in open cavities of the closure unit by suppressing the formation of germs for as long as possible.

The foil is multi-layered and includes at least one metallic layer and one plastic layer and one adhesive or sealing layer.

In this manner, the foil prevents or at least minimizes the risk of moisture absorption in various hollow spaces of the closure unit and thus excludes the risk of microbiological growth. In fact, the invention includes the finding that re-closable lids for beverage cans are more problematic in this respect than conventional tear-open lids, since most of the closure units on the outer side of the lid have a more complex geometry than the usual tear-open lids and are thus more sensitive to microbiological contamination. Moreover, closure units often include plastic component parts which are more receptive to microbiological contamination that the bright or lacquer-coated metallic faces of conventional tear-open lids.

According to a preferred embodiment, on the outer side of the lid the foil completely covers the closure unit. According to alternative embodiments, however, the foil may have clearances, wherein in this case the the periphery or the peripheries of a respective clearance is/are connected to a surface of the closure unit in a tight manner—preferably likewise entirely. On its part, the surface of the closure unit which lies within such a clearance in the foil is preferably completely closed, such that, together with the foil and the lid surface, a completely closed surface results.

The foil and the connection of the foil to the lid surface are preferably conceived such that the foil is irreversibly deformed during removal. This permits the additional functionality of proof of being genuine.

Since the foil completely covers the closure unit on the outer side of the latter, the foil has to be initially removed in order to be able to open a respective beverage can. By providing that the foil is irreversibly deformed in the process, the deformed foil, in the manner of a seal, may serve as proof and indication of the respective beverage can having been closed at origin. According to a variant of an embodiment, the foil and the connection of the foil to the lid surface are conceived such that the connection to the lid surface is so strong that the foil is stretched and thus irreversibly deformed during removal.

According to the invention, the foil is multi-layered and preferably includes at least one metallic layer, such that the foil not only makes for a liquid-tight closure but also for a gas-tight closure. The foil here includes at least three layers, namely one metallic layer, one plastic layer, and one adhesive or sealing layer. The latter serves for connecting the foil to the lid surface.

Alternatively, the foil may also be breathable, in that said foil is composed of a plastic which contains breathable polymers, for example.

In light of the fact that at least some component parts of the closure unit typically reach outwards beyond the lid surface, it is preferable for the foil to be pre-shaped in such a manner that said foil is adapted to a contour of component parts of the closure unit which reach outward beyond the lid surface. The foil is thus preferably pre-fashioned in such a manner that said foil follows the contour of the closure unit. This implies that the portions of the foil which are intended for connection to the lid surface already run at least approximately in the plane of the lid surface, when a foil of this type is applied to the lid. That is to say that the application of the foil to the lid does not coincide with comparatively large deformations of the foil, such that in this manner a reliable and tight connection between the foil and the lid surface can be more easily ensured.

In the case of usual lids, the lid surface is part of a shell which, besides the lid surface, also includes at least one reinforcement bead which entirely encloses the lid surface and which, in a surface inclination, transitions into the lid surface. In lids of this type it is preferable for the foil to be connected to the shell not only in the region of the lid surface but also beyond a circumferential periphery of the lid surface. This is particularly advantageous where a drinking opening which is to be closed by the closure unit is disposed close to the periphery of the lid surface and thus also comparatively near the reinforcement bead. In this case, the face of the lid surface which is available between the closure unit and the circumferential periphery of the lid surface is so narrow that it is advantageous for the foil to reach beyond this circumferential periphery and to also be fixedly connected to the surface inclination which is adjacent to the circumferential periphery. In this manner, a more secure and tighter connection between the foil and the shell of the lid can be manufactured. The shell of the lid is typically formed by an integral metal plate which is correspondingly shaped.

According to the invention, a method for manufacturing a lid of the type mention above is also proposed, according to which method the foil is applied to the remainder of the lid by means of a flexible, for example an elastic, pressing stamp, wherein the pressing stamp is configured such that it adapts to the contour of the closure unit during application of the foil. It can be ensured in this manner that the foil during application to the remainder of the lid, securely and entirely bears on the lid, more specifically on the shell of said lid. This is particularly significant because the region between the closure unit and the circumferential periphery of the lid surface is typically very small.

According to a preferred variant of the method, the foil, after application, is thermally treated. In this manner, it can be ensured, in particular, in the case of a foil which is substantially formed by a thermoplastic material that the shape of the foil after application accurately adapts to the surface contour of the lid, including the closure unit. The thermal treatment of the foil may take place by way of various media and, for example, may be conjoint with mechanical pressing by means of an elastic stamp, for example. However, the thermal treatment of the foil may also take place in a non-contacting manner.

The invention is now to be explained in more detail by means of an exemplary embodiment with reference to the figures. In the figures:

FIG. 1a shows a cross section through a lid according to the invention, including the closure unit and the foil; and

FIG. 1b shows a lid, similar to that in FIG. 1a, having an alternative foil.

In FIGS. 1a and 1b, in each case one lid 10 or 10′, respectively, which, in the manner of known lids, includes a shell which is shaped from an integral metal plate and which forms a lid surface 12, a reinforcement bead 14, and a core-wall inclination 16, is illustrated. The lid surface 12 here is entirely enclosed by the reinforcement bead 14. In the plan view, the shape of the reinforcement bead 14 is typically circular. The reinforcement bead 14, in a surface inclination 18, transitions into the lid surface 12.

The lid surface 12 includes a through-opening which, in the case of re-closable lids, is closed by a closure unit 20 which typically includes a closure element 22 lying on the inside and an actuation element 24 lying on the outside. Since the closure element 22 is disposed on the inner side of the lid 10 or 10′, respectively, in the case of carbonated beverages said closure element 22, on account of an internal pressure prevailing in a beverage can, is pressed from the inside against the shell of the lid 10 or 10′, respectively, such that a secure closure is also ensured in the case of beverage cans having internal pressure. The closure element 22 lying on the inside is typically connected to the actuation element 24 lying on the outside by way of a variously designed drive, such that, by means of the actuation element 24 lying on the outside, said closure element 22 can be moved into a position in which the closure element 22 uncovers the opening in the lid surface 12. Details of the design of closure units of this type are known from the prior art.

According to the invention, on the outer side of the lid 10 or 10′, respectively, a foil 30 or 30′, respectively, which completely covers the component parts of the closure unit 20 which lie on the outside, and the outer periphery of which is connected to the lid surface 12 and optionally also to the surface inclination 16 in a fixed manner but, when used, in a releasable manner, is provided. This connection may be established by way of an adhesive layer of the foil 30 or 30′, respectively, or else also by way of a sealing layer which is connected to the lid surface 12 and optionally the surface inclination 18 under the effect of heat, for example.

In the case of the exemplary embodiment in FIG. 1a, the foil 30 is formed by a preferably thermoplastic layer and, moreover, also includes a sealing or adhesive layer.

In the case of the exemplary embodiment in FIG. 1b, the foil 30′ is of multi-layered construction and includes an outer plastic layer and a metallic layer lying therebeneath. The metallic layer makes for good gas tightness of the foil 30′. In turn, the metallic foil, on its inner side (that is to say the side facing the lid surface), may be laminated with a further plastic layer, or also be directly provided with an adhesive or sealing layer. In particular, a foil 30′ according the variant depicted in FIG. 1b has the property of irreversibly deforming during removal and, having been removed once, of thus not being able to be re-applied to the lid 10′ in its original state. In this case, a pristine foil 30′ indicates to a consumer that the respective can has indeed never been opened but has been closed at origin.

LIST OF REFERENCE SIGNS

• 10, 10′ Lid
• 12 Lid surface
• 14 Reinforcement bead
• 16 Core-wall inclination
• 18 Surface inclination
• 20 Closure unit
• 22 Closure element
• 24 Actuation element
• 30, 30′ Foil

Claims

1. A lid for a beverage can or similar, having a lid surface and a closure unit which is to be opened and is re-closable, which is disposed in the region of the lid surface, and which selectively uncovers or closes a drinking opening in the lid surface, wherein the lid, in the use state, has an inner side pointing to the inside of the can and an outer side pointing to the environment,

characterized in that on the outer side of the lid a foil which, on the outer side of the lid, completely covers the closure unit and, around the closure unit, is entirely connected to the lid surface by means of an adhesive or sealing layer so as to be tight in such a manner that, on account of the connection between the foil and the lid surface, ingress of moisture is prevented or at least substantially prevented, is disposed, wherein the foil is multi-layered and includes at least one metallic layer and one plastic layer and the adhesive or sealing layer.

2. The lid according to claim 1, wherein the foil and the connection of the foil to the lid surface are conceived such that the foil is irreversibly deformed during removal.

3. The lid according to claim 1, wherein the foil is breathable.

4. The lid according to claim 1, wherein the foil is pre-shaped in such a manner that said foil is adapted to a contour of component parts of the closure unit which reach outwards beyond the lid surface.

5. The lid according to claim 4, wherein the foil is pre-fashioned in such a manner that said foil follows the contour of the closure unit in such a manner that the portions of the foil which are intended for connection to the lid surface already run at least approximately in the plane of the lid surface, when a foil of this type is applied to the lid.

6. The lid according to claim 1, in which the lid surface is part of a shell which, besides the lid surface, includes a reinforcement bead which encircles the lid surface and which, in a surface inclination, transitions into the lid surface, characterized in that the foil is connected to the shell beyond a circumferential periphery of the lid surface.

7. The lid according to claim 1, wherein the foil completely covers the closure unit on the outer side of the lid.

8. Method for manufacturing a lid according to claim 1, wherein on the outer side of the lid a foil which, on the outer side of the lid, completely covers the closure unit and, around the closure unit, is entirely connected to the lid surface by means of an adhesive or sealing layer so as to be tight in such a manner that, on account of the connection between the foil and the lid surface, ingress of moisture is prevented or at least substantially prevented, is applied, wherein the foil is applied to the remainder of the lid by means of a flexible, for example an elastic, pressing stamp, wherein the pressing stamp is configured such that it adapts to the contour of the closure unit during application of the foil.

9. The method according to claim 8, wherein the foil, after application, is thermally treated.