FIELD OF THE INVENTION

The present invention relates to plastic packaging, in general and, in particular, to plastic packaging including tamper evidence.

BACKGROUND OF THE INVENTION

Conventional plastic packaging includes a bottom portion, which is a container that holds the products, and a lid to close the container. Plastic containers can be formed by several different technologies. One known technology is mennoforming, typically vacuum forming. Conventional thermoformed packaging having tamper evidence includes a single clam shell-like unit including an integrally manufactured lid and bottom portion, hinged to one another by a flexible plastic hinge. This means that they must both be made of the same material, of the same thickness and the same color.

A second technology for forming plastic packaging is injection molding.

Plastic containers formed by injection molding are typically formed of two separate parts, a lid and a bottom portion, which may be formed of different materials, and/or of different colors, if desired. However, injection molding for food packaging requires polypropylene as the raw material and has a very high tooling cost, so the molds for these containers are very expensive.

Many types of tamper evidence are known in packaging that make unauthorized access to products inside the container easily detectable. Frangible or break-away locks and one-way pull-tight and ladder locks which cannot be reattached are also used.

Tamper evidence can be provided on injection molded and on thermoformed packaging. Typically, tamper evidence in clamshell packaging is provided by the hinge portion that connects the two parts of the clamshell that must be torn in order to open the packaging. Tamper evidence can also be provided on two part packaging, typically only on the lid, or only on the bottom part of the container, a portion of which must be torn off in order to permit separation of the lid from the bottom portion to open the packaging.

Accordingly, there is a long felt need for inexpensive but effective tamper evidence on a two part packaging, and it would be very desirable if this tamper evidence lock is arranged on the two parts of the packaging.

SUMMARY OF THE INVENTION

The present invention relates to plastic packaging formed from a bottom portion and a complementary lid that are separately and independently formed, preferably, although not necessarily, by thermoforming. When coupled to one another, the lid and the bottom portion form a tamper evident lock that must be broken in order to open the packaging and separate the lid from the bottom portion. Separately thermoforming the lid and the bottom portion permits the use of a lid that is significantly thinner than the bottom portion, resulting in savings in manufacturing costs. In addition, the lid and the bottom portion can be formed of different materials and/or of different colors, as desired.

Thus, there is provided, according to the present invention, a plastic container including a bottom portion, a complementary lid formed separately and independently from the bottom portion, and a tamper evidence lock including a frangible portion. The tamper evidence lock has a first portion integrally formed with the lid and a complementary second portion integrally formed with the bottom portion, for locking the lid to the bottom portion when the first portion is locked to the second portion forming the tamper evidence lock.

According to some embodiments of the invention, the lid and the bottom portion are formed independently by memoforming.

There is also provided, according to embodiments of the invention, a method for providing tamper evidence for a plastic container, the method including forming a lid having an integrally formed first portion of a tamper evident lock, separately and independently forming a complementary bottom portion having an integrally formed second portion of the tamper evident lock, the tamper evident lock including a frangible portion, placing the lid on the bottom portion, and lockingly engaging the first portion and the second portion of the tamper evident lock so as to frangibly lock the lid to the bottom portion.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be further understood and appreciated from the following detailed description taken in conjunction with the drawings in which:

Figure 1 is a schematic illustration of tamper-evident plastic packaging constructed and operative in accordance with one embodiment of the present invention;

Figure 2 is a schematic illustration of the packaging of Figure 1, once the frangible portion is removed or folded away;

Figure 3a is a sectional illustration of the tamper evident lock of Figure 1; Figures 3b to 3e are sectional illustrations of the method of operation of the tamper evident lock of Figure 1;

Figure 4a is a schematic illustration of tamper-evident plastic packaging constructed and operative in accordance with an alternative embodiment of the present invention;

Figure 4b is a schematic illustration of the packaging of Figure 4a, once the frangible portions are removed or folded away;

Figures Sa to Sd are sectional illustrations of the operation of the tamper evident lock of Figure 4a;

Figure 6a is a schematic illustration of tamper-evident plastic packaging constructed and operative in accordance with another alternative embodiment of the present invention;

Figures 6b and 6c are schematic illustrations of the packaging of Figure 6a, once the frangible portions are partially and completely removed or folded away, respectively; Figures 7a and 7b are sectional illustrations of the tamper evident lock of Figures 6b and 6c, respectively;

Figure 8a is a schematic illustration of tamper-evident plastic packaging constructed and operative in accordance with a further alternative embodiment of the present invention;

Figure 8b is a schematic illustration of the packaging of Figure 8a, once the frangible portion is partially and completely removed or folded away;

Figure 8c is a sectional illustration of the tamper evident lock of Figure 8a;

Figure 9a is a schematic illustration of the packaging of Figure 8a, once the frangible portion is removed or folded away;

Figure 9b is a sectional illustration of the tamper evident lock of Figure 8a, once the frangible portion is removed or folded away;

Figure 9c is a schematic illustration of the packaging of Figure 8a in the open orientation; and

Figure 9d is a sectional illustration of the tamper evident lock of Figure 9a.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to plastic packaging having tamper evidence. In particular, it relates to plastic packaging including a bottom portion which contains the goods or products, a complementary, separately and independently formed lid, and a tamper evident lock, portions of which are formed on the lid and complementary portions of which are formed on the bottom portion. The complementary portions of the tamper evidence lock are locked to one another after filling the container such that the packaging can only be opened by breaking the lock. When the lock is broken, it provides evidence of possible opening of the lid from the bottom portion. Thus, a frangible plastic lock, that provides tamper evidence, is formed of two portions complementary to one another, one integrally formed with the lid and one integrally formed with the bottom portion and arranged to lock to one another after the container is filled. Preferably, the edges of the lid fit securely into an undercut or groove or channel in the inner wall of the bottom portion or in another relatively inaccessible portion of the bottom portion. In this way, it is very difficult to insert a finger or tool and pry, partially or completely, the lid from the bottom without tearing or removing the frangible portion. In this way, the lock provides an indication of whether the package has been opened and the contents possibly tampered with.

Referring now to Figure 1, there is shown a schematic illustration of tamper- evident packaging 10 constructed and operative in accordance with one embodiment of the present invention. Packaging 10 includes a lid 12 and a complementary bottom portion 14. Lid 12 and bottom portion 14 are formed individually and independently, preferably, although not necessarily, by tiiermoforming. A first portion of a tamper evident lock is formed on the lid 12 and a second, complementary portion of the lock is formed on the bottom portion 14. In this embodiment, the frangible portion of a tamper evident lock 16 is integrally formed with bottom portion 14. Tamper evident lock 16 includes a frangible breakaway or foldable component 18 which cannot be reattached after tearing or bending. Frangible portion 18 may be defined by perforated or scored lines or lines weakened in any other known manner. This prevents access to the goods inside the packaging until the packaging is opened, and demonstrates that the packaging has not been opened. Once the frangible portion is removed or folded away, as shown schematically in Figure 2, the user can open the packaging by separating the lid from the bottom portion.

Figure 3a is a sectional illustration of the tamper evident lock 16 of Figure 1 in use. Goods (not shown) have been inserted into the packaging bottom portion 14 and the bottom portion is closed with the lid 12. The second portion of the tamper evident lock 16 that is integrally formed with the bottom portion 14 is sealingly coupled to the complementary first portion, here illustrated as a locking member 17 that is integrally formed with the lid 12.

Figures 3b to 3e are sectional illustrations of the method of locking the tamper evident lock of Figure 3a. As can be seen most clearly in Figure 3b, the second portion of the tamper evident lock 16 of this embodiment includes three portions- a base portion 20, a frangible portion 18, and a locking portion 22, separated by weakened lines 23 and 25. Base portion 20 defines an upstanding protrusion 24. Locking portion 22 includes a locking recess 26 which is configured to frictionally engage a complementary locking recess 28 on the first portion of the tamper evident lock 16, namely, a locking member 17 integrally formed with the lid 12.

When the packaging has been filled (not shown), the lid 12 is placed on the bottom portion 14, such that the edge 13 of the lid frictionally engages the upper edge IS of the bottom portion. See Figures 3b to 3e, enlarged illustrations of the tamper evident lock of Figure 1. In this position, protrusion 24 of base portion 20 of the tamper evident lock 16 is located beneath and adjacent to locking recess 28 of the lid. Frangible portion 18 and locking portion 22 are now folded along scored or perforated or otherwise weakened lines 23 and 25, and locking recess 26 is pressed into complementary locking recess 28 until the lid is locked to the base, as by snap fit of the first and second portions of the tamper evident lock. The distal end 27 of the locking portion 22 rests against and engages a portion of the lid. In this way, the lid cannot be separated from the bottom portion and the tamper evident lock cannot be disengaged and unfolded without breaking the frangible portion 18. If desired, the tamper evident lock can be further strengthened by defining an undercut (not shown) in the portion of the lid against which locking portion 22 rests and locking portion 22 can be slightly longer than the locking member 17. In this way, the distal end 27 of locking portion 22 can be inserted into the undercut, thereby providing reinforcement to the tamper evident lock.

Figures 4a to 5d are schematic illustrations of tamper-evident packaging 30 constructed and operative in accordance with an alternative embodiment of the present invention. Figure 4a is a schematic illustration of tamper-evident packaging 30 in a closed and locked orientation. Packaging 30 includes a lid 32 and a bottom portion 34. Lid 32 and bottom portion 34 are formed, individually and independently, preferably, although not necessarily, by mermoforming. A first portion of a tamper evident lock is formed on the lid 32 and a second portion of the lock is formed on the bottom portion 34. Packaging 30 is similar to packaging 10 but the frangible portion of tamper-evident lock 36 is integrally formed with lid 32 instead of with bottom portion 34. Tamper evident lock 36 includes a frangible breakaway or foldable component 38 which cannot be reattached after tearing or bending. Frangible portion 38 may be perforated or scored or weakened in any known manner. This prevents access to the goods inside the packaging until desired, and demonstrates that the packaging has not been opened. In the illustrated embodiment, two tamper-evident locks 36 are provided, one on either side of the packaging.

In order to gain access to the goods (not shown) in the bottom portion 34 of the packaging of Figure 4a, the frangible portion 38 must be torn and removed. Once the frangible portion is removed or folded away, as shown schematically in Figure 4b, the user can open the packaging by separating the lid from the bottom portion.

Figures Sa to 5d are sectional illustrations of the tamper evident lock of Figure 4b. The first portion of tamper evident lock 36 of this embodiment includes three sections - a top section 40, a frangible section 38 and a locking section 42. Top section 40 defines a depending protrusion 44. Locking section 42 includes a locking recess 46 which is configured to frictionally engage a complementary locking recess 48 on the locking member 37 of the second portion of the lock, on the bottom portion 34.

When the packaging has been filled (not shown), the lid 32 is placed on the bottom portion 34 such that the edge 33 of the lid frictionally engages a channel 35 formed by the upper edge of the bottom portion. In this position, protrusion 44 of top portion 40 of the tamper evident lock 36 is disposed above and adjacent to locking recess 48 of the bottom portion. Frangible portion 38 and locking portion 42 are now folded along scored or perforated or otherwise weakened lines 43 and 45 and locking recess 46 is pressed into complementary locking recess 48 until the lid is locked to the bottom portion by the tamper evident lock, as seen in Figures 5c and 5d. The distal end 47 of the locking portion 42 rests against and engages a depending skirt on locking member 37 of the lid.

If desired, the tamper evident lock can be further strengthened by defining an undercut (not shown) in the portion of the lid against which locking portion 42 rests and locking portion 42 can be slightly longer than the locking member 37. In this way, the distal end 47 of locking portion 42 can be inserted into the undercut, thereby providing reinforcement to the tamper evident lock.

It will be appreciated mat, in these embodiments, the tamper evident lock is structured in such a way as to allow the user to bend or shape it into place. Once it is snap-fit or pressed into place, there is no access to edges of the packaging to permit someone to separate the lid from the bottom portion and the tamper evident lock cannot be disengaged and unfolded without breaking the frangible portion.

Referring now to Figures 6a to 7b, mere are shown schematic illustrations of tamper-evident packaging 50 constructed and operative in accordance with an alternative embodiment of the present invention. Packaging 50 includes a lid 52 and a separately and independently formed bottom portion 54. Packaging 50 preferably is formed by thermoforming, although other methods of manufacture can, alternatively, be employed. Packaging 50 includes a tamper evident lock 56, a first portion thereof being formed on lid 52 and a second portion thereof being formed on bottom portion 54. Tamper evident lock 56 includes a frangible breakaway or foldable portion 58, which may be perforated or scored or weakened in any known manner. In this embodiment, frangible portion 58 is integrally formed with bottom portion 54. A locking member 57 on the lid is arranged for interlocking engagement by the snap-fit of its edges under the tamper evident lock. Once the frangible portion is removed or folded away, as shown in Figure 6c, the user can open the packaging by separating the lid from the bottom portion.

Figures 7a and 7b are sectional illustrations of the tamper evident lock of

Figure 6a. As can be seen, tamper evident lock 56 of this embodiment includes three sections - a base section 60, frangible section 58, and a locking recess 62. When the packaging has been filled (not shown), the lid 52 is placed on the bottom portion 54. As the lid is pressed into place, locking member 57 engages locking recess 62 and creates the tamper-evident lock. In this way, the lid cannot be separated from the bottom portion and the tamper evident lock cannot be disengaged and unfolded without breaking the frangible portion.

Figures 8a to 8c are schematic illustrations of tamper-evident packaging 70 constructed and operative in accordance with an alternative embodiment of the present invention in a sealed orientation. Packaging 70 includes a lid 72 and a separately and independently formed bottom portion 80. Packaging 70 preferably is formed by thermofonning, although other methods of manufacture can, alternatively, be employed. Bottom portion 80 defines a peripheral channel 82 and a central recess 84 for receiving goods to be packaged. Lid 72 is an integral lid having three parts. A sealing portion 74 is substantially coextensive with the bottom portion 80. Sealing portion 74 includes a depending ridge 76 adapted and configured to frictionally and sealingly engage peripheral channel 82 of the bottom portion. An openable and recusable portion 78 of lid 72 is affixed by a hinge 79 to sealing portion 74. Lid 72 also includes a tamper-evident lock 90 having a first, frangible portion 92 formed on the lid. Frangible portion 92 is disposed in registration with a recess 86 in bottom portion 80, which serves as a second portion of the tamper evident lock 90.

As shown in Figures 9a to 9d, breaking frangible portion 92 of tamper- evident lock 90 permits openable portion 78 of lid 72 to be separated or torn from sealing portion 74 to provide access to goods inside central recess 84. Frangible breakaway or foldable portion 92 may be perforated or scored or weakened in any known manner.

It will be appreciated that, since the lid and the bottom portion of the packaging of the present invention are separately and independently formed, they can be formed of different materials, of the same material but of different thicknesses, of different colors or textures, or in any other fashion that is desired. Suitable materials include not only polypropylene, but also MPET, polystyrene, and other suitable polymers. In addition, a heat-sealed foil can be provided to cover goods in the packaging before the lid is sealed to the bottom portion, if desired. This is the case for any of the embodiments described or illustrated herein.

It will further be appreciated that, in each of the embodiments of the invention, tamper evidence is provided by a tamper evidence lock having a first portion integrally formed with the lid and a second portion integrally formed with the bottom portion. When the first portion is locked to the second portion, the tamper evidence lock is created between the lid and the bottom portion. The tamper evidence lock includes a frangible portion which, when broken, provides access to an edge of the lid so that the lid to be removed from the bottom portion to open the packaging, and provides evidence that the packaging has been opened.

While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made. It will further be appreciated that the invention is not limited to what has been described hereinabove merely by way of example. Rather, the invention is limited solely by the claims which follow.