GB2228253A

GB2228253A - Containers

Info

Publication number: GB2228253A
Application number: GB8903694A
Authority: GB
Inventors: Ian Alexander Webb; Timothy Sutton
Original assignee: NPM International
Current assignee: NPM International
Priority date: 1989-02-17
Filing date: 1989-02-17
Publication date: 1990-08-22
Anticipated expiration: 2009-02-17
Also published as: GB8903694D0; GB2228253B

Abstract

A container is made in one piece from polymeric sheet material, e.g. by vacuum forming, and comprises a bottom panel (10), an outer wall (14, 28) joined to an intermediate panel (16) recessed to hold a product, and a cover panel (12). There is an air space (42) between the bottom of the product-holding compartment (38) and the bottom panel (10). The container may be closed with tamper evident means. It is especially suitable for holding foods sold ready to be heated in a microwave oven and then eaten from the container. <IMAGE>

Description

CONTAINERS This invention relates to containers for containing a food product.

Examples of such containers include those in which prepared or partly-prepared food is sold, ready to be eaten from the container itself after the user has heated, cooked or completed the cooking of the food, typically in a microwave oven. Such products are well known as "TV dinners" or the like, and the containers typically comprise a tray with recesses for the various food items, the tray being mounted in a carton which defines the bottom portion with an outer covering. When the food is being cooked, the tray may need to be removed from the carton and the food may be eaten from the tray with the latter resting directly on a table or on the lap of the user; alternatively it may be arranged so that the whole container can be put in the microwave oven and the food eaten from it with the carton resting on the lap or table.

Commonly, the food is packed, for example by aseptic packaging techniques, in retort pouches which are simply placed in the container during the packing operation, to be taken out of the pouches by the user when preparing the food for eating.

Known containers in which food is sold ready for eating from the container after a minimum of preparation and/or heating by the user are composite containers, comprising at least two components of different materials, and are comparatively expensive both to make and to erect, sometimes (for example where the food is packed in retort pouches within the container) calling for some work on the part of the user which partly negates the advantage of having food available that is ready to eat with no preparation other than a short spell in a microwave oven.

According to one aspect of the invention there is provided a container comprising a closable compartment for the contents supported on a base, the compartment being spaced from the base to form an air space to insulate the contents from the base.

Conveniently, the container may be provided with an inlet and an outlet for the passage of air through the air space.

According to another aspect of the invention there is provided a container comprising a profiled tray sandwiched between two faces of the container to form a cavity between the tray and the outer walls of the container.

Conveniently, the container is formed from sheet material in one piece, and comprises a cover panel, an intermediate panel, a bottom panel and a generally upstanding outer wall, and having a base portion which has a front boundary and a rear boundary and which comprises the bottom panel and at least a portion of the outer wall, with the intermediate and cover panels being joined to the base portion along its said front and rear boundaries respectively, the intermediate panel having at least one recessed portion for containing a product, and the outer wall being deeper than the recessed portion or portions, whereby when the container is closed the cover panel overlies the intermediate panel, which in turn overlies the base portion with a space between the bottom of the (or each) recessed portion and the bottom panel.

The container is preferably made of a polymeric sheet material, and by vacuum forming.

The abovementioned space below the recessed portion or portions containing the product is preferably an air space which serves several purposes. If the product is heated in a microwave oven, the container can easily be arranged so that microwave energy can pass through this air space so that the food becomes irradiated from the bottom as well as from other directions. This reduces heating time and makes for more even heating. The air space need not be hermetically closed, so that the air in it can remain at the same pressure as the atmosphere outside the container, and distortion of the container due to heating of the air in the air space (e.g. by conduction from the food via the base of the recess in which it lies) is avoided. Finally, the user can place the container on the lap or on a table without heat from the food reaching the bottom panel in contact with the lap or table.The air in the air space then has a thermal insulating effect which helps keep the food hot.

Since the container is in one piece, in which connection it may be formed in a single forming operation followed by one simple erecting operation, it can be made quite inexpensively, thus reducing packaging costs.

In a preferred construction the container comprises a blank, for a generally-rectangular container wherein the base portion includes a front portion and a rear portion of the outer wall, defining the respective front and rear boundaries of the base portion, and the outer wall comprises the said front and rear wall portions and a pair of end wall portions, comprises the bottom panel joined to the cover and intermediate panels through the rear and front outer wall portions respectively, and having securing means whereby, when the container is erected with the wall upstanding with respect to the bottom panel, free edges of the intermediate panel and of the end wall portions can be secured so as to hold the container in its erected state.

Where the container is to be used for food or other products for which tamper evidence is required, the container after being filled and closed, is preferably rendered unopenable without breaking a tamper evident means, which may for example comprise an outer envelope applied by shrink wrapping.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a plan view on a blank, laid flat, for a container in a first embodiment; Figure 2 is a section on the line II-II in Figure 1; Figure 3 is a sectional view of the same container when erected, taken generally on the same line II-II; Figure 4 is a scrap section on the line IV-IV in Figure 3; and Figure 5 is a general-view showing a second embodiment of the container, in an unfolded condition.

Figure 6 is a perspective view showing a third embodiment of the container in an unfolded condition.

The blank seen in Figures 1 and 2 is made in one piece of polymeric material in sheet form, and comprises a bottom panel 10, joined to a cover panel 12 through a rear outer wall portion 14 and to an intermediate panel 16 through a front outer wall portion 18.

The panel 10 and wall portions 14 and 18 can be regarded as together constituting a base portion (generally indicated at 20), having a front boundary line 22 along which the panel 16 is joined to it, and a rear boundary line 24 along which the panel 12 is joined to it, these boundaries being the outer limits of the wall portions 18, 14 respectively.

The intermediate panel 16 includes a securing flap 26 extending along its side opposite the line 22. A pair of outer wall end portions 28 extend from the remaining sides of the panel 16, being continuous therewith. Each wall end portion 28 terminates in a securing flap 30.

The cover panel 12 has a front flap 32 with a securing tab 34. Hinge lines 36 are made by any known method along the junctions between the various panels, wall portions, and flaps. In the hinge line between the panel 10 and wall portion 18, a small slot 37 is provided to engage the tab 34 when the container is erected and closed.

The intermediate panel 16 has two dish-like recessed compartments 38, and the bottom panel 10 has a recessed portion 40 to serve as a strengthening and reinforcing means. In this example this takes the form of a cruciform rib, concave downwards as seen in Figure 2. The depth A (Figure 2) of the dish compartments 38 is less than the depth B of each outer wall portion, by an amount greater than the depth C of the rib 40.

In this connection, it should be noted that, for clarity of detail, Figure 2 is not to scale.

The blank may conveniently be made in a single vacuum forming operation, in which its outline, the hinge lines 36, the dish compartments 38, the rib 40 and the slot 37 are all formed simultaneously.

The blank is erected by folding in the appropriate directions at the hinge lines 36 and securing the flaps 26, 30, to give the erected container shown in Figures 3 and 4.

Referring therefore to Figures 3 and 4 which show the container closed, with the tab 34 engaged in the slot 37 the flap 26 is secured by welding (or possibly by a suitable adhesive) to the inside of the rear outer wall portion 14, while the flaps 30 are similarly secured to the bottom panel 10, so that the intermediate panel overlies the base portion 20 and is generally parallel to the bottom panel, from which it is spaced through a generally upstanding outer wall. It will be noticed that this wall consists of the four wall portions 14, 16, 28 and is therefore not closed at the corners.

Because of the relationship between the dimensions A, B and C mentioned above, there is a clear space 42 between the bottom of the dish compartments 38 and the bottom panel 10. With the corners of the outer wall open, this space 42 is open to the atmosphere.

The cover panel 12 overlies the intermediate panel so that, when closed, it covers the products (indicated at 44 in Figure 3) placed in the dish compartments 38.

These products may for example be foodstuffs suitable for cooking in a microwave oven.

In use for food packaging, the container can be employed in any convenient manner. For example, the food may be placed in the container in an aseptic filling and closing machine, the cover 12 then being mechanically closed and the container sealed while still within the sterile environment of the machine. The container may be provided with venting apertures as required.

Sealing of the container may be carried out in any convenient way. It should be noted that only the joint between the cover panel 10 and intermediate panel 16 need be sealed as far as preserving the product from contact with the atmosphere is concerned. Thus, strips 50 of peelable adhesive may be provided along the underside (the upper side in Figure 2) of the panel 12 at the side edges of the latter, with the front flap 32 being for example provided with a conventional tamperindicating tear portion as indicated at 52 in Figure 1 and being secured adhesively to the front of the outer wall below this tear portion, in known manner. The tab 34 and slit 37 then may not be necessary. Instead of adhesive the container may be sealed by other methods such as crimping or ultrasonic seam welding.Ideally the cover or top section should be ultrasonically welded with a tear strip to open the container.

Alternatively, with the cover simply held closed by the tab 34, the whole filled container may be hermetically sealed within an outer wrap, for example by a conventional shrink wrapping process. Printed labels or ribbons may be attached to the container or any tearoff device which may be used in a promotional capacity or for competition purposes.

The user opens the pack so that the cover panel 12 loosely overlies the food, and then cooks the food in a microwave oven for a suitable time. The cooking process is facilitated by the fact that the food is spaced at 42 from the bottom panel 10, enabling microwave energy to reach the food from below as well as from above and from the sides. The food may then be eaten direct from the container, with the latter resting on the user's lap, which is then insulated from the heat of the food by virtue of the air space 42.

The container may be made of a transparent or opaque material.

The side walls of the container may be attached to the cover or lid to prevent ingress of dirt at the point of sale.

Numerous variations may be envisaged, apart from those mentioned above. A few examples of such variations will be touched upon below.

The wall portions 28 may extend from the bottom panel 10 as indicated at 28 in Figure 1, either instead of extending from the panel 16 or in addition. In the former case their flaps 30 may be welded to the underside of the panel 16; in the latter case, at each end of the container, the two wall portions are secured together to form together the full height of the outer wall. In this case the wall end portions need not each be the full height of the wall. They can be secured together by welding or by a suitable adhesive, or by purely mechanical means, such as simple securing tabs projecting from the edge of one of the portions and engaging in slots in the other. In Figure 1, such tabs and slots are indicated in phantom at 60 and 62 respectively.

Similarly, instead of using welding or an adhesive to secure the flap 26 to the wall portion 14, tabs 64 and slots 66 may be provided.

Another variation is shown in Figure 5, in which the body portion of the container is in the form of a hollow dish 120 which may for example be vacuum formed.

It comprises the bottom panel 110 and the outer wall 108, upstanding from the panel 110 and formed integrally with it. The front and rear boundary lines 122 and 124, along which the intermediate panel 116 and cover panel 112 are respectively joined, are again hinge lines at the top of the body portion. The height of the wall 108, and the depth of the other dish compartment 138, in which product is placed, are again so chosen that there is a free space between the dish compartment 138 and bottom panel 110.

The wall 108 may be perforated to enable this free space to communicate with the atmosphere.

The containers need not he for foodstuffs but may be used for other products; similarly they need not be intended for holding a product to be heated.

Nevertheless they are particularly suitable for holding footstuffs or other products to be heated in a microwave oven. They need not be of polymeric or other synthetic plastics materials, and may for example be of paperboard, metal or a laminate of one or more layers, any or all of which may be of a plastics material, paper or metal.

Metal of course cannot be used in microwave ovens. One suitable material, where the container is to be used for microwaveable foodstuffs, is polyethylene terephthalate.

The container is particularly useful under controlled laboratory conditions or in controlled atmospheric packaging.

The container need not be rectangular in plan, but may be of any other desired shape, for example round, oval, or with parallel front and back walls but curved end walls. In the case of a round or oval body portion, the outer wall then consists, of course, of a single wall portion.

The dished compartment for holding the product can be of any number (Figure 5 shows a single such compartment) and of any shape and size in plan.

Integral reinforcing means may be provided in the cover panel 12 or 112, and/or in the base of each recess 38 or 138. Reinforcing means are optional in the bottom panel 10 or 110, but are desirable to ensure sufficient rigidity in the pack for stacking purposes and, especially after opening. The reinforcing means can be of any desired shape and dimensions, and may be formed by pressing, thermoforming injection moulding or folding fabrication.

The third embodiment shown in Figure 6 is similar to Figure 5 and shows a profiled tray 208 sandwiched between two faces 209 and 210 of the container generally indicated at 230. The depth of the tray compartment 211 is shallower than that of the container to form a cavity between the tray and the outer walls of the container 230.

It will be appreciated that the container can be used with the contents under very hot or very cold conditions.

The relatively rigid construction of the container with the isolated contents compartments particularly lends itself to the packaging of fragile materials, e.g.

laboratory samples or electrical components which are "cradled" from knocks or sharp objects.

The space surrounding the compartments may be filled with heat insulating materials e.g. plastic foam which can easily follow the contours of the compartments.

It will be understood that the container may be provided with any convenient number of compartments to accommodate food, i.e. the main course and the sweet as well as for cutlery, napkins and condiments all of which can be hermetically sealed in a sterile environment.

Claims

CLAIMS:

1. A container comprising a closable compartment for the contents supported on a base, the compartment being spaced from the base to form an air space to insulate the contents from the base.

2. A container according to Claim 1 wherein the container is provided with an inlet and an outlet for the passage of air through the air space.

3. A container comprising a profiled tray sandwiched between two faces of the container to form a cavity between the tray and the outer walls of the container.

4. A container formed in one piece from sheet material, comprising a cover panel, an intermediate panel, a bottom panel and a generally upstanding outer wall, and having a base portion which has a front boundary and a rear boundary and which comprises the bottom panel and at least a portion of the outer wall, with the intermediate and cover panels being joined to the base portion along its said front and rear boundaries respectively, the intermediate panel having at least one recessed portion for containing a product, and the outer wall being deeper than the recessed portion or portions, whereby when the container is closed the cover panel overlies the intermediate panel, which in turn overlies the base portion with a space between the bottom of the (or each) recessed portion and the bottom panel.

5. A container according to any of the preceding Claims, made from polymeric sheet material.

6. A container according to Claim 4, wherein at least the bottom panel is provided with reinforcing means.

7. A container according to Claims 5 and 6, wherein the reinforcing means comprise at least one further recessed portion.

8. A container according to Claim 5 or Claim 7, wherein the (or each) recessed portion of the container is made by vacuum forming.

9. A container according to any one of the preceding claims, wherein the base portion includes a front portion and a rear portion of the outer wall, defining the respective front and rear boundaries of the base portion.

10. A container according to Claim 9, wherein the outer wall comprises the said front and rear wall portions and a pair of end wall portions.

11. A container according to Claim 10, wherein the end wall portions are continuous with the intermediate panel, means being provided to attach the end wall portions to the base portion.

12. A container according to Claim 9 or Claim 10, wherein the base portion is in the form of a hollow dish comprising the entire outer wall joined integrally with the bottom panel.

13. A container according to Claims 5 and 12, wherein the base portion is formed by vacuum forming.

14. A blank for a generally-rectangular container according to Claim 10, the blank comprising the bottom panel joined to the cover and intermediate panels through the rear and front outer wall portions respectively, and having securing means whereby, when the container is erected with the wall upstanding with respect to the bottom panel, free edges of the intermediate panel and of the end wall portions can be secured so as to hold the container in its erected state.

15. A pack comprising a container according to any one of claims 4 to 13, with a product in the or each of the said recessed portions of the intermediate panel, the container being closed and being sealed by tamper evident means.

16. A pack according to Claim 15, wherein the tamper evident means comprises an outer envelope applied by shrink wrapping.

17. A pack according to Claim 16, wherein the tamper evident means comprises an outer envelope applied by shrink wrapping.

17. A blank for a container, substantially as hereinbefore described with reference to Figures 1 and 2 of the accompanying drawings.

18. A container substantially as hereinbefore described with reference to Figures 3 and 4 of the accompanying drawings.

19. A container substantially as hereinbefore described with reference to Figure 5 of the accompanying drawings.

20. A container substantially as hereinbefore described with reference to Figure 6 of the accompanying drawings.

Amendments to the claims have been filed as follows 1. A packaging container for containing at least one product such as a foodstuff, comprising a recessed support element, for holding the product and adapted so that an operation can be carried out on the product in the support element, a base element supporting the support element and defining a space between the base element and the support element for thermal insulation, and a cover element for overlying the support element so as to close the container, the container comprising a single piece of ovenable material in sheet form whereby the product can be heated in the container.

2. A container according to Claim 1, wherein the material is polymeric.

3. A container according to Claim 2, wherein the material is polyethylene terephthalate.

4. A container according to any one of the preceding claims, wherein at least the support element and the base element are thermoformed.

5. A container according to any one of the preceding claims, wherein the container is provided with an inlet and an outlet for the passage of air through the said space.

6. A container according to any one of the preceding claims, comprising a cover panel of the cover element, an intermediate panel constituting the support element, a bottom panel, and a generally upstanding outer wall, the base element comprising a base portion which has a front boundary and a rear boundary and which comprises the bottom panel and at least a portion of the outer wall, with the intermediate and cover panels being joined to the base portion along its said front and rear boundaries respectively, the intermediate panel having at least one recessed portion for containing a product, and the outer wall being deeper than the recessed portion or portions, whereby when the container is closed the cover panel overlies the intermediate panel, which in turn overlies the base portion with a said space between the bottom of the (or each) recessed portion and the bottom panel.

7. A container according to Claim 6, wherein the base portion includes a front portion and a rear portion of the outer wall, defining the respective front and rear boundaries of the base portion.

8. A container according to Claim 7, wherein the outer wall comprises the said front and rear wall portions and a pair of end wall portions.

9. A container according to Claim 7 or Claim 8, wherein the base portion is in the form of a hollow dish comprising the entire outer wall joined integrally with the bottom panel.

10. A container according to any one of the preceding claims, wherein the cover element is in the form of a hollow dish having a flange around its open mouth, the base element having a complementary flange whereby, when the container is closed, an inner face of the cover element flange overlies, and is releasably sealed to, an outer face of the base element flange.

11. A container substantially as hereinbefore described with reference to Figs. 3 and 4 of the accompanying drawings.

12. A container substantially as hereinbefore described with reference to Fig. 5 of the accompanying drawings.

13. A container substantially as hereinbefore described with reference to Fig. 6 of the accompanying drawings.

14. A blank for a generally-rectangular container according to Claim 8 or Claim 9, wherein the bottom panel is joined to the cover panel and to the intermediate panel through the rear and front outer wall portions respectively, the blank including securing means whereby, when the container is erected with the outer wall upstanding with respect to the bottom panel, free edges of the intermediate panel and of the end wall portions can be secured so as to hold the container in its erected state.

15. A blank for a container, substantially as hereinbefore described with reference to Figs. 1 and 2 of the accompanying drawings.

16. A pack comprising a container according to any one of Claims 1 to 13, with a product in the support element, the container being closed and being sealed by tamper evident means.