Thermoformed container

Abstract

A thermoformed container comprises a tray having walls that join a bottom surface and form an opening opposite the bottom surface. The walls are curved where they join the bottom surface. A tray flange surrounds the opening and extends outwardly from the walls. A lid has a recessed panel surrounded by peripheral sides, wherein the lid and the tray are configured to lock together. A lid flange surrounds the peripheral sides and extends outwardly therefrom. Marks on the bottom surface are configured to indicate increments of the bottom surface.

Description

FIELD OF THE INVENTION

The present invention relates generally to the field of plastic packaging and particularly to thermoformed containers.

BACKGROUND

Packaging of a wide variety of food products has increasingly used thermoformed containers. The wide variety of food products is typically held in the thermoformed containers until consumed by a consumer or for a period of time corresponding to an adequate shelf life of the contained food products. The thermoformed containers may be reclosable or re-sealable to protect food products, such as spreads, dips and the like, with a cover or lid. The thermoformed container may be designed to be an adaptable combination of a tray and a lid. The lid for such reclosable thermoformed containers is disconnectedly adapted to fit a flange of the tray to permit access to an interior of the container. Depending upon the type of food products, the tray is typically designed to be formed with one or more compartments.

The thermoformed containers are typically formed by heating a plastic sheet between two heated platens and drawing it down into a mold cavity or over a form utilizing vacuum, or pressure, or both. The thermoformed plastic containers are rigid or semi-rigid plastic film structures with relatively sturdy walls, of the type that are intended for long-term use by the consumer. The thermoformed containers are useful for hot and cold foods as they provide a degree of thermal insulation.

Conventionally, a retail bar package for cream cheese is difficult to open and remove the product. The retail cream cheese package can be a wrapper folded over a rectangular shaped cream cheese bar and sealed along two short sides and a longer side of the wrapper. Retail cream cheese can also often be hot filled as a liquid into a pouch and then sealed, cooled and cartoned. In addition the current retail cream cheese packages are not equipped with re-sealable sides or edges. Further, consumers generally tend to desire a product packaging that provides a visual marking that may denote an incremental division of the packaged product.

In view of the above discussed problems, it would desirable to provide a rigid reclosable thermoformed container that facilitates easy removal of the packaged product and that includes incremental markings.

BRIEF SUMMARY

In accordance with an embodiment of the present invention, a thermoformed container comprises a tray having walls that join a bottom surface and form an opening opposite the bottom surface. The walls are curved where they join the bottom surface. A tray flange surrounds the opening and extends outwardly from the walls. A lid has a recessed panel surrounded by peripheral sides, wherein the lid and the tray are configured to lock together. A lid flange surrounds the peripheral sides and extends outwardly therefrom. Marks on the bottom surface are configured to indicate increments of the bottom surface.

In another embodiment of the invention, a thermoformed container for holding a food product comprises a tray having walls that join a bottom surface and form an opening opposite the bottom surface. The walls are curved where they join the bottom surface. A tray flange surrounds the opening and extends outwardly from the walls. A lid has a recessed panel surrounded by peripheral sides, such that the lid and the tray are configured to lock together. A lid flange surrounds the peripheral sides and extends outwardly therefrom. Marks on the bottom surface are configured to indicate increments of the bottom surface, such that images corresponding to the marks are transposed on the food product after settling into the tray, to enable easy division of the food product into increments corresponding to the marks when the food product is removed from the thermoformed container.

In yet another embodiment, a combination of a food product in a thermoformed container comprises a volume of food extruded out of a metering device and settled into a tray of the thermoformed container. At least one image on a bottom surface of the food product corresponds to at least one mark on a bottom surface of the tray. The at least one image enables easy division of the food product into increments when the food product is removed from the thermoformed container.

Further aspects and advantages of the invention are described below in conjunction with the present embodiments

BRIEF DESCRIPTION OF THE DRAWING

The invention, together with the advantages thereof, may be understood by reference to the following description in conjunction with the accompanying figures, which illustrate some embodiments of the invention:

FIG. 1 is a perspective assembly view of a thermoformed container with a tray and a lid in accordance with one embodiment of the invention;

FIG. 2 is shows perspective views of the thermoformed container illustrated in FIG. 1 with the lid removed from the tray;

FIG. 3a-3d are a bottom view and a cross-sectional view along line A-A of the assembled container, a close up of a cross sectional view of lid projections engaged with tray grooves along circle C, and a bottom view of the lid in accordance with an embodiment of the invention; and

FIG. 4 is a bottom perspective view of the assembled thermoformed container illustrated in FIG. 1.

DETAILED DESCRIPTION

While the present invention may be embodied in various forms, there is shown in the drawings and will hereinafter be described some exemplary and non-limiting embodiments, with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiments illustrated.

In this application, the use of the disjunctive is intended to include the conjunctive. The use of definite or indefinite articles is not intended to indicate cardinality. In particular, a reference to “the” object or “an” object is intended to denote also one of a possible plurality of such objects.

Referring to FIG. 1, a thermoformed container 10 is generally shown. The thermoformed container 10 has a tray 12 and a lid 14. Both the tray 12 and the lid 14 are generally box-like structures. The tray 12 is formed by a sidewall having four interconnected peripheral walls 16 and 18, namely two opposing long walls 16, and two opposing short walls 18. In addition, the tray 12 has diagonally opposed corners 20 and 22. The diagonally opposed corners 20 and 22 are diagonally pair matched in relation to tray 12. The lid 14 is formed by a relatively shallow sidewall having four interconnected peripheral sides 24 and 26, namely two opposing long sides 24 and two opposing short sides 26. The four interconnected peripheral sides 24 and 26 are commonly connected at one end to a recessed panel 27. The peripheral sides 24 and 26 form a depression surrounded by a peripheral lid flange 28 that extends outwardly therefrom.

Referring to FIG. 2, the four peripheral walls 16 and 18 taper at one respective end to an integral bottom wall 25, and form at another respective end an opening 37. The opening 37 is surrounded by a tray flange 38 that extends outwardly therefrom. The diagonally opposed corners 20 and 22 are thus pair matched diagonally in relation to the bottom wall 25. As such, one diagonal pair of corners 20 has a larger radius than that of the other diagonal pair of corners 22. Alternately, corners 20, and 22 can have substantially the same radius.

The peripheral lid flange 28 has a bottom surface that substantially mirrors an upper surface of the tray flange 38 for sealing purposes. Alternately, the lid flange 28 may overlap the tray flange 38 in at least one corner. For example, to enable an ease of opening of the container 10 in one corner the lid flange 28 may be configured with a correspondingly greater radius than the tray flange 38.

Still referring to FIG. 2, a thermoformed container 10 is provided as an adaptable reclosable combination of the tray 12 and the lid 14. To prevent access to an interior of the container 10, an external peripheral side surface of lid 14 adjacent to the lid flange 28 is configured to fit an interior peripheral surface of the tray sidewall adjacent to the top flange 38. The recessed panel 27 facilitates pushing the lid 14 down into the opening 37 of the tray 12 to lock the lid 14 onto the tray 12 to close the thermoformed container 10. Accordingly, the lid 14 will be securely positioned in the tray 12. By locking the lid 14 to the tray 12, inadvertent or otherwise undesirable opening of the container 10 prior to an intentional opening can be substantially minimized. In one embodiment, the peripheral sides 24 and 26 of the lid 14 have a depth of about ⅛″ to about ¼″, and more preferably about ¼″.

In accordance with an embodiment of the invention, the lid 14 sealably closes the tray 12 in a substantially tight closure while rendering the container 10 readily openable. The substantially tight closure of the container 10 minimizes any release of the closure due to jerky and motions of the closed container 10. The closure also provides protection from the outside environment while the container 10 is closed. The container 10 is preferably configured to be opened with a moderate amount of force by a smooth and constant pulling force applied to the lid 14. Alternately, the closure minimizes a susceptibility to leaking.

Referring to FIGS. 3a-3d, in one embodiment of the invention, to enhance the closure of the container 10, the tray 12 includes grooves 29 and the lid 14 includes projections 39. The grooves 29 open on the inside surface of the tray walls 16 and 18 are formed along a substantially horizontal direction near the tray flange 38. The grooves 29 project outwardly from the outside surface of the tray walls 16 and 18. The projections 39 are formed in horizontal series in the peripheral sides 24 and 26 near the lid flange 38, and project outwardly thereform. The grooves 29 engage the corresponding projections 39 to secure the lid 14 to the tray 12. When the tray 12 is closed with the lid 14, the downward sliding movement of the lid 14 into the tray 12 is arrested when lid projections 39 snap into the corresponding grooves 29. Those skilled in the art will appreciate several alternative structures configured to secure the lid 14 to the tray 12. For example, locking lugs, and the like can be configured in the tray 12 and the lid 14.

In one alternate embodiment, the tray 12 and the lid 14 include tapered sides and walls to create a friction fit type of locking or securing closure of the container 10. In another alternate embodiment, the lid flange 28 and the tray flange 38 include a pressure sensitive adhesive that enables the container 10 to be opened and reclosed.

In a preferred embodiment, the tray 12 and the lid 14 are formed from a rigid plastic film structure. The rigid plastic film structure acts an oxygen barrier to improve the shelf life of the food products enclosed in the thermoformed container 10. The tray 12 is formed out of a molded single sheet of thermoplastic material. In the molding process, the bottom wall 25 is concavely molded near the upwardly extending walls 16, and 18.

Preferably, both the tray 12 and the lid 14 are made from materials that contain a release or non-stick agent such as glycerol mono stearate, and the like. The release agent allows the contained products to be easily removed or popped out of container 10 by the consumer. Alternately, the inner surfaces of the tray 12 and a bottom surface of the lid 14 can be treated with a suitable releasing agent in order to prevent sticking. For example, by applying the releasing agent to the inner surfaces of the tray 12, a block of cheese can be removed substantially in its entirety from the tray 12.

When initially filled, the container 10 is hermetically sealed across the tray flange 38 and the lid flange 28. The tray flange 38 and lid flange 28 are provided with sealant layers 41 on respective mirror surfaces. That is, the sealant layers 41 are applied to a top surface of the tray flange 38 that mirror a bottom surface of the lid flange 28. In one embodiment, the sealant layer 41 is a peelable seal that allows the lid 14 to be easily removed from the tray 12 by the consumer. The sealant layers 41 are designed to release the lid flange 28 from the tray flange 38 by a cohesive failure of the seal. To facilitate easy opening of the container 10, the sealant layers 41 are applied to the entire sealing surfaces of the flanges 28 and 38. Accordingly, the sealant layers 41 are not heat sealed along a distal portion of at least one of the flange corners of both the tray 12 and the lid 14. In this way, the container 10 is easily opened at the corresponding corners of the tray 10.

The sealant layers 41 can also enable the container 10 to be resealed when the sealant layers 41 of the tray flange 38 and the lid flange 28 come in contact with each other again. The sealant layers 41 can comprise pressure sensitive adhesive to facilitate opening and re-closing of the tray 12 with the lid 14. In the preferred embodiment, the container 10 and the sealant layers 41 are strong enough that the container 10 will not bulge or burst when a stacking pressure is applied to the container 10. For example, the container 10 is subjected to stacking pressure when positioned in a similar stack of containers 10. The sealant layers 41 protect food products in the container 10 from oxygen and moisture. The peelable sealing layers 41 are designed to promote a separation of the closing surfaces of the lid flange 28 and the tray flange 38 with a moderate amount of force. Concurrently, the lid 14 is readily removable from the tray 12 to provide access to the interior of the container 10.

Once the seal has been broken, the container 10 may be opened by applying opposing finger pressures to the lid flange 28 and to the tray flange 38. Alternately, overlapping release tabs (not shown) can be included in the lid flange 28 or in the tray flange 38, or both, which extend outwardly to provide finger graspable regions. In one embodiment, the lid 14 has instructional indicia positioned on the lid flange 28. For example, the lid flange 28 can include instructions to the consumer on how to break the seal and how to separate the lid 14 from the tray 14.

From the foregoing, the tray 12 and the lid 14 can be locked together by pushing down on the recess panel 27 of the lid 14, or by engaging the projections 39 into the grooves 29 or by the sealant layers 41 when the lid flange 28 and the tray flange 38 are brought into contact with one another, or by any combination of these alternatives.

A cream cheese product is preferably packaged under conditions such that the package has an adequate shelf life, in an unopened and refrigerated state, of at least three months, and, more preferably, at least four months or longer. Referring to FIG. 4, for home or other retail uses, the thermoformed container 10 may preferably contain about 4 ounces to about 16 ounces and more preferably, about 8 ounces of food product, such as for example cream cheese. In one preferred embodiment, raised marks 42 are formed into the bottom wall 25 of the tray 12. The raised marks 42 are configured to transpose their respective images onto the contained food product. Corresponding marks 44, such as numbers or letters, or both, are also formed into the tray 12 and are also configured to transpose their images to the contained food product. In one embodiment, the marks 44 indicate the size of the increments, for example 1 oz. In this preferred embodiment, when the contained food product is removed from the tray 12 and deposited upside down onto a working surface, the tranposed raised marks 42 and 44 enable the consumer to easily divide the product in uniform increments. Alternately, the marks 42 or 44, or both, may be formed onto at least one sidewall 16, and 18 of the tray 12.

In a preferred embodiment, the tray 12 and the lid 14 are configured to provide a relatively stable stack of filled containers 10. For example, it is desirable that a stack of containers remain in vertical alignment with no substantial lateral play between the lids and the trays of each container. To enable the containers 10 to be stacked to a desired height, an inner surface of the recess panel 27 is configured to accommodate the concave surface of the bottom wall 25 of the tray 12. As such, the bottom wall 25 is configured to substantially engage the next adjacent lid 14 in the stack of containers 10 while minimizing a lateral movement of the stacked containers 10 relatively to one another. Accordingly, configuring the tray 12 and lid 14 in accordance with the preferred embodiment enable the containers 10 to be stacked in such a way so as not to become jammed together when subjected to an axial compressive load.

In one embodiment, packing of the tray 12 with food products, such as cheese, is carried out by extruding the cheese out of a metering device, such as piston filler (not shown) into the tray 12. When a desired amount of cheese product has been metered out, the cheese product will settle into the tray 12. The open tray 12 is then closed and sealed with the lid 14 by pushing the lid 14 into the tray 12, or by lockingly engaging the projections 39 into the grooves 29, or by pressing both flanges 28 and 38 together to heat seal the sealant layers 41 deposited on the corresponding surfaces of the tray flange 28 and the lid flange 28.

Preferably, one may apply a printed label (not shown) or wrap the container with a printed paperboard sleeve (not shown) to provide packaging information on the container 10.

While a preferred embodiment of the invention has been described, it should be understood that the invention is not so limited, and modifications may be made without departing from the invention. For example, the raised marks may be formed into a bottom surface of the recesses panel so that they are potentially visible to the consumer, and corresponding marks are transposed on a topside surface of the cheese product when the lid is initially locked together with the tray 12. These transposed surface markings, represented by numbers or letters, or both, provide the consumer with an easy indication of the product increments and their corresponding sizes. The marks may include inks, dyes, food colorings, and the like. Therefore, it is intended that all such variations and modofications fal within the scope of the appended claims, and equivalents thereof.

Claims

1. A thermoformed container comprising:

a tray having walls that join a bottom surface and form an opening opposite the bottom surface,

wherein the walls are curved where they join the bottom surface;

a tray flange surrounding the opening and extending outwardly from the walls;

a lid having a recessed panel surrounded by a peripheral sidewall,

wherein the lid and the tray are configured to lock together;

a lid flange surrounding the peripheral sidewall and extending outwardly therefrom; and

marks on the bottom surface that are configured to indicate measure increments.

2. The thermoformed container of claim 1, wherein the marks further comprise numbers.

3. The thermoformed container of claim 1, wherein the marks further comprise letters.

4. The thermoformed container of claim 1, wherein the marks are configured to indicate substantially equal increments.

5. The thermoformed container of claim 1, wherein the marks are transposed on a contained product, thereby enabling easy division of the contained product into corresponding increments when the contained product is removed from the thermoformed container.

6. The thermoformed container of claim 1, wherein the recessed panel comprises a structure that enables the lid to be pushed down into the opening to lock the lid and the tray together.

7. The thermoformed container of claim 1, wherein a bottom surface of the lid flange substantially mirrors structurally at least a portion of an upper surface of the tray flange for sealing purposes.

8. The thermoformed container of claim 1, wherein the tray flange and the lid flange comprise structures that form a hermetic seal.

9. The thermoformed container of claim 8, wherein the flange of the tray and the flange of the lid further comprise sealant layers to hermetically seal the container.

10. The thermoformed container of claim 8, wherein the hermetical seal comprises a peelable seal that enables the lid to be easily removed from the tray.

11. The thermoformed container of claim 1, wherein the tray and the lid comprise substantially rigid plastic film structures.

12. The thermoformed container of claim 1, wherein the tray and the lid comprise substantially semi-rigid plastic film structures

13. The thermoformed container of claim 11, wherein the substantially rigid plastic film structure comprises an oxygen barrier material.

14. The thermoformed container of claim 12, wherein the substantially semi-rigid plastic film structure comprises an oxygen barrier material.

15. The thermoformed container of claim 11, wherein the substantially rigid plastic film structure comprises a release agent.

16. The thermoformed container of claim 12, wherein the substantially semi-rigid plastic film structure comprises a release agent.

17. The thermoformed container of claim 13, wherein the release agent comprises glycerol mono stearate.

18. The thermoformed container of claim 14, wherein the release agent comprises glycerol mono stearate

19. The thermoformed container of claim 1, wherein the tray walls further comprise grooves thereon and the lid sides further comprise projections thereon.

20. The thermoformed container of claim 19, wherein the projections engage the grooves when the lid and the tray are brought together.

21. The thermoformed container of claim 19, wherein the projections comprise structures arranged in series.

22. The thermoformed container of claim 19, wherein the lid and the tray are configured such that a downward sliding movement of the lid into the tray is arrested when the lid projections engage the corresponding grooves of the tray.

23. The thermoformed container of claim 1, wherein the tray and the lid further comprise corresponding locking lugs.

24. A thermoformed container for holding a food product comprising:

a tray having walls that join a bottom surface and form an opening opposite the bottom surface,

wherein the walls form a curved surface where they join the bottom surface;

a tray flange surrounding the opening and extending outwardly from the walls;

a lid having a recessed panel surrounded by a peripheral sidewall,

wherein the lid and the tray are configured to lock together;

a lid flange surrounding the peripheral sidewall and extending outwardly therefrom; and

marks on the bottom surface that are configured to indicate increments of the bottom surface,

wherein images corresponding to the marks are transposed on the food product after settling into the tray, thereby enabling easy division of the food product into increments corresponding to the marks when the food product is removed from the thermoformed container.

25. The thermoformed container of claim 24, wherein the marks further comprise at least one of numbers and letters to indicate a size of the increments.

26. In combination, a food product in a thermoformed container, the combination comprising:

a volume of food extruded out of a metering device and settled into a tray of the thermoformed container; and

at least one image on a bottom surface of the food product, the at least one image corresponding to at least one mark on a bottom surface of the tray,

wherein the at least one image enables easy division of the food product into increments when the food product is removed from the thermoformed container.