Patent Publication Number: US-2004040964-A1

Title: Can top having a space for separately storing a small quantity of a substance

Description:
[0001] The present invention pertains to a can top, and especially a beverage can top, for crimping onto a corresponding can body. The can top is designed so that additives can be stored therein separately from the remaining can contents, which [additives] reach its interior and are thus possibly in contact with the remaining can contents only when opening the can.  
       [0002] For a long time there has been a demand for storing additives for the contents of cans, e.g., beverage flavoring additives separately from the remaining can contents so that they come into contact with the remaining contents only when the can is opened for its specified use. Corresponding internal containers for cans have already been suggested. However, most of these internal containers are only suitable for foamy beverages under gas pressure, since the blending of the separately stored, flavoring substance is linked with the generation of a sudden difference in pressure that forms between a gas-filled space within the internal container connected with the rest of the liquid by a very small opening and the pressure of this liquid. This difference in pressure is used for forcing open the wall of the space in the internal container that is used for storing the additive. Examples of this principle are shown in WO 99/54229 or in EP 965 536 A1.  
       [0003] An internal container has become known from U.S. Pat. No. 5,885,635, which, suitably arranged in the can, breaks by means of contact with a tongue that descends down when opening the can and releases a second liquid, which can then be mixed with the beverage in the can, regardless of the gas pressure in the can. However, this internal container must be a rigidly elastic body that is designed such that it contains energy stored in the form of tension, in such a manner that a slight activation energy only is needed to release this tension by means of breaking the container. The body should, accordingly, have the shape of a cylinder or a pea pod with a lengthwise running bursting edge. U.S. Pat. No. 5,885,635 does not explain how such an internal container [sic, typo in original—Tr.Ed.] could be prefabricated, filled with liquid and then sealed.  
       [0004] U,S. Pat. No. 5,290,574 discloses the suggestion to arrange a gas- and liquid-permeable membrane under the top of beverage cans for foamy beverages and to fasten this [membrane] all-around in the area of the crimped edge. After sealing the can the space between the top and the membrane is then filled—either by pasteurizing or by placing the can upside down—partly with liquid, which then lies on the membrane when standing the can upright, based on the excess pressure prevailing in the can interior. If the can is opened, first the pressure in the compartment located between the top and the membrane drops suddenly, which causes gas to shoot out of the gas space between the liquid level of the beverage and the membrane through its openings into the liquid located above the membrane, which leads to a first formation of foam as well as the formation of seeds for the further formation of gas bubbles after pouring out. If the tear-open strip is opened further by the descending tongue, the membrane can then tear, as a result of which an outlet opening is formed for the beverage. As an alternative, it may be provided that the membrane covers only a portion of the pouring opening. In this case, it does not need to be torn open or otherwise removed, since both the contents of the compartment formed by the membrane with the top and the remaining beverage located in the can are able to be poured next to one another directly through the opening in the can top. Both liquids (the compartment separated by the membrane may additionally contain a foam stabilizer, e.g., a sugar solution) are then mixed when pouring out.  
       [0005] The object of the present invention is to create, using simple means, a space within a can, which is provided for the storage of a small quantity of a substance separately from the remaining contents of the can during the storage of the can, whereby this space, when the can is opened, likewise opens without further measures and delivers liquid or solid substances possibly contained therein to the remaining can contents, regardless of whether or not the can contents are under gas pressure and/or are supposed to foam.  
       [0006] The object of the present invention is accomplished in that the said space is provided in the area of the top of the can and is formed at least partially by a flexible, but essentially non-expandable, gas-tight and liquid-tight wall. This wall does not require any internal tension or any potentially stored kinetic energy here. The space is arranged near the pouring opening, in such a manner that its edge crosses a slit line provided in the top surface, which, when opening the can top, is torn open by means of a likewise provided tear-open strip. When the can is opened, the tongue, to which the strip is fastened, is pressed into the interior of the can, as is well known from the state of the art. The wall in the edge area of the said space is destroyed; an opening is formed, through which the substance inserted into the space beforehand can escape. 
     
    
    
     [0007] The figures show various embodiments of the present invention:  
     [0008] In the embodiment of FIG. 1, the space is limited toward the can interior by a foil, toward the top by the top material itself.  
     [0009]FIG. 1 a  shows a lateral view of this embodiment with the tear-open tongue pressed inwards, and  
     [0010]FIG. 1 b  shows this embodiment schematically viewed from the interior, whereby the point of intersection of the slit line and the edge area of the space can be seen.  
     [0011]FIG. 2 shows another embodiment, in which the space is formed by two foils that are connected with one another in their edge area, such that they form a pocket. The pocket is fastened in the interior of the top surface.  
     [0012]FIG. 2 a  represents a lateral view of this embodiment, likewise with the tear-open tongue pressed inwards, and  
     [0013]FIG. 2 b  shows a top view of this embodiment on the inside of the top, whereby a notch can be seen in the area of intersection between the slit line and the connected edge area of the pocket.  
     [0014]FIG. 3 shows a spatial view of a foil partially detached from the top by the tongue. 
    
    
     [0015] The present invention is especially suitable for beverage cans, e.g., made of metal, since, when the substance stored separately beforehand is opened, whether it now be gaseous, solid or liquid, it can reach into the beverage or the atmosphere surrounding the beverage and can bring about a flavoring or enrichment of the beverage. Thus, a solid in the form of a powder or crystals or a liquid, when opening the can, can come into contact with the remaining beverage contents and possibly be mixed therewith, e.g., a concentrate, a flavoring, a coloring or the like. Even a gaseous or highly volatile aroma may be stored in the said space. This [aroma] stimulates the sense of smell when consuming the can contents, especially if one drinks directly out of the can. Besides or instead of odor-giving or taste-giving substances, the space provided at the can top may also be used for accommodating food supplements. This may be, e.g., the agent of choice, if the stability of these substances is not guaranteed for the long term in a liquid or if the additive might enter into conversion reactions with the contents of the beverage. An important field in this regard are sports or health beverages, which may be enriched with pro- or prebiotic substances, as well as with the muscle-building preparation creatine. It is advantageous to mix together such substances only immediately before consuming the beverage.  
     [0016] The wall, by which the additional substance to be stored is separated from the remaining contents of the can, should be flexible and at least essentially impermeable to liquids and gases; “essentially impermeable” should mean that a gaseous substance, with which the space arranged according to the present invention may be filled, also remains effective for a long time in this space, while the wall must represent only a moderately effective barrier for oxygen, but also possibly is gas-tight against oxygen. The material for this wall may be selected at random as long as it is not expandable in such a manner that it gives way to the pulling of the tear-open strip when opening. Examples of suitable materials are metal foils, e.g., aluminum foils, plastic films or optionally cardboard coated with a material or such paper that repels the main content(s) of the can and/or the substance to be stored separately.  
     [0017] In a simple embodiment of the present invention, the space for the storage of the said substance is formed by a foil or another flexible material being fastened at the top surface with the formation of a hollow space. The external outline of the foil may be selected at random, e.g., round, oval or even polygonal, as long as the edge of the body or of the foil connected with the top surface crosses the slit line at at least one point. As an example for this embodiment of the present invention, a round or oval aluminum foil may be mentioned, which is arranged centrally in the top surface and fastened at the top surface on its outer edge. In this case, it crosses the slit line at two points. However, it should be clear that it is sufficient if the foil crosses the slit line at only one point.  
     [0018] In this embodiment of the present invention, the substance to be stored separately is arranged on the inside of the preshaped top, which is otherwise preferably ready, and is optionally fixed by means of cold or another measure. The top surface may optionally have a small, circumferential projection in order to hold a drop or the like in position. Subsequently, the foil is applied and is fastened in a sealing manner, e.g., glued, heat-sealed or sealed, whereby the space for storing this substance is sealed. It is only opened when the can—after filling and sealing with the top, e.g., by crimping—is opened by pulling on the tear-open strip.  
     [0019] In another simple embodiment of the present invention, the space for accommodating the substance to be stored separately is formed by a pocket or another flexible hollow body, which is fastened in the top surface of the can top. A pocket is obtained if a foil-type material is used. E.g., the foils, which were mentioned above for the simple embodiment, are suitable as materials.  
     [0020] The pocket or the other flexible hollow body, finished and completely filled, may be fastened at the inside of the top, whereby the fastening can be performed, e.g., by means of gluing with an adhesive permitted in accordance with food laws or by means of sealing. To produce the pocket, e.g., two foils are connected, e.g., glued, sealed or heat-sealed, with one another in their edge area, between which the substance to be stored separately is arranged. As an alternative, e.g., half of a foil may be placed onto the other half and sealingly connected with same, e.g., glue or be connected by sealing. The bond preferably has a width of about 1 mm (e.g., 0.5 mm) up to a few millimeters (e.g., 5 mm). Preferably the pocket or the hollow body is relatively flat, e.g., has a lens-shaped design. Regarding the remaining geometry, the person skilled in the art is free in his choice, as long as the lateral edge of the pocket or of the otherwise flexible hollow body crosses the slit line at at least one point. In this embodiment, “crossing” does not have to inevitably mean that the edge itself is connected with the top at the slit line; it is sufficient if the connection area is arranged sufficiently close to the slit line and the movability of the material at this point is sufficiently low that a tear in the foil or the like is forced when opening the tear-open strip.  
     [0021] If the space for the substance to be stored separately is provided in the form of a pocket or otherwise hollow space, it is preferred that a notch, which weakens the wall at this point and functions as a desired tear point, is provided in the edge area that extends over the slit line.  
     [0022] The present invention shall be explained below in detail based on figures:  
     [0023]FIGS. 1 a  and  1   b  show an embodiment of the present invention, in which the space  8  provided for the substance to be stored separately is formed by a foil  4 , which is fastened with its lateral edge  6  on the inside of the top  1 . FIG. 1 a  shows a lateral view, while FIG. 1 b  shows a top view of the inside of the top. It can be seen from a combination of the two views that, when opening the can, in which the tongue  2  is pressed into the interior of the can, the foil is detached by means of the rivet  12  up to the slit line  3  approximately from the point of intersection  11  between the slit line  3  and its edge  6  up into the area of a vertical line  13  to the axis of symmetry S. This area of detachment  5  is shown shaded in FIG. 1 b.    
     [0024]FIG. 3 shows the result of this detachment process in a spatial view. The top surface is designated by  14  here.  
     [0025]FIG. 2 shows an embodiment of the present invention, in which the space for the substance to be stored separately is designed as a pocket  9 . This [pocket] is formed by two foils  4 ′,  4 ″, which are connected with one another on their lateral edges in the area  6 ′. The foil  4 ′ facing towards the top surface is connected with same over the greater portion of its underside, but not in the area of the edge  6 ′. In the example of this figure, the pocket is shown as round; however, it could also, e.g., be formed by means of only an oval or round foil by folding the left half onto the right half. FIG. 2 b  shows the notch  7 , which is arranged in the area, in which the edge  6 ′ of the pocket crosses the slit line  3 . The notch is less wide than the edge width, such that a narrow bridge to the outer edge  10  of the interior remains. FIG. 2 a  shows that this bridge, when opening the can and when pressing in the tongue  2 , is torn inwards, so that the contents of the pocket can reach the environment, e.g., the beverage. If the substance is a liquid and/or gaseous aroma, the consumer feels an intensive olfactory experience, since the aroma is released directly at the top and thus when drinking directly from the can near the nose of the consumer.