The invention relates to a container, and particularly, but not exclusively to a food product container for bakery produce.

It is known to provide food product containers comprising a tray/container body for containing the food product, and separate lid formed of another material, such as plastics. The use of a transparent plastics lid is often preferred to allow customers to see the product being sold, but the tray/container body may be formed of some other material, such as paperboard. For the purposes of this specification, the term 'paperboard' is considered to encompass paper, cardboard and other similar materials.

Many retailers now sell food products that are freshly made, sometimes in store, such as baked goods. These products are indented to be consumed shortly after purchase, so hermetically sealed containers are not required. However, where separate trays/container bodies and lids are provided, it is important that the fit between the components is reasonable secure so that the container body and lid do not become separated if, for example, a customer were to pick up the packaged product by the lid rather than the container body. The use of adhesive tape or tabs, or similar additional closure/sealing means is possible, but customers can become frustrated if the resulting packaging is fiddly or difficult to subsequently open, and in-store staff will similarly become frustrated if forming and closing the container is complex and/or time consuming.

One solution to these problems is to include one or more features on the container body to engage with or cooperate with corresponding features provided on the lid. The most common example of this is to provide shaped protrusions from the wall of a plastics lid which engage with corresponding apertures provided in a container body.

A problem, however, still remains with vacuum formed plastics lids. The vacuum forming process places a limit on the size of protrusions that can be formed in the side wall of a lid. If protrusions are made too large, the lid cannot be readily removed/ejected from the vacuum forming machine. The result of this is that the protrusions that can readily be formed in a vacuum forming process are not large enough to engage sufficiently with apertures in the container body to retain the components together. This problem can be addressed, to a certain extent, by making the various components more rigid and providing a tight tolerance between the lid and container body. However, this requires the use of a larger amount of raw materials in the manufacture of each lid and container, and makes it far more difficult for staff to assemble the packaging in store, so is generally undesirable.

It is an object of the present invention to provide a container, and in particular a container body or tray, that overcomes the problems identified above.

According to the present invention there is provided a container as recited in the appended claim 1. Further beneficial features are recited in the associated dependent claims. The container comprises a tray and a lid, the tray having an aperture for receiving a protrusion formed in the lid, and a tab for engagement with the protrusion when the protrusion is received in the aperture.

The engagement of a free edge of the tab with the protrusion provides additional resistance against separation of the tray and lid, and allows for the use of relatively small protrusions in the lid, which is beneficial to the production of the lid component.

Preferably more than one protrusion, tab and aperture are provided. There may be equal numbers of apertures, tabs and protrusions, or the number of apertures and protrusions may exceed the number of tabs, such that each tab engages with more than one protrusion.

To provide resistance around an entire tray, four apertures may be provided for receiving four protrusions. Two or four tabs may be provided for engaging the protrusions. The tray may be formed of paperboard and/or may be formed from a folded blank. Paperboard containers are environmentally sound and easily printed with company specific graphics or information. Fixing means, such as one or more glue dots, may be provided on the blank for securing the tabs in a folded position to simplify manufacture of the container.

The lid may be formed of a plastics material and may be vacuum formed.

The protrusions may be provided in side walls of the lid. The apertures may be provided in side walls of the tray.

A better understanding of the present invention will be obtained from the following detailed description of a preferred embodiment thereof. The description is given by way of example only and makes reference to the accompanying drawings in which: Figure 1 is a perspective view of a tray/container body according to the present invention;

Figure 2 is a perspective view of a lid for use with the tray /container body of Figure 1 ;

Figures 3 to 8 are plan views of the process of forming the tray/container body of Figure 1 from a flat blank; and

Figure 9 is a perspective view of an alternative tray/container body according to the present invention.

An example tray, or container body 1, is shown in Figure 1. A lid 2, for use with the tray 1, is shown in Figure 2. The container body 1 has side walls 4 and end walls 6 which overlap with side walls 8 and end walls 10 of the lid 2 when the when the lid 2 is applied to the container body 1 to form a closed container. The top edges of the end walls 6 of the container body 1 are slightly curved to match a slight curve provided at the top of the lid 2. The side walls 4 of the container body 1 are generally rectangular. The container body 1 of Figure 1 is received within the lid 2 of Figure 2 when the container is assembled and closed, but it is also possible that the lid 2 could be received within the container body 1. Likewise, although the side and end walls 4,6,8,10 of both the container body 1 and the lid 2 are shown in the Figures as substantially vertical, it would be possible to provide a container body 1 with angled walls an a lid 2 with similarly angled side walls.

Protrusions 12 are provided in the side walls 8 of the lid 2 for engagement with apertures 14 in the side walls 4 of the container body 1. Four apertures 14 are shown in the container body 1 of Figure 1 (although only three are visible), and four corresponding protrusions 12 are shown in Figure 2. More, or fewer, apertures and protrusions could be provided if desired, and could alternatively, or additionally, be provided in other walls of the container body 1 and the lid 2. It is possible that only one aperture 14 and one protrusion 12 could be provided for engagement. At the top of the side walls 4 of the container body 1, tabs 16 are provided. Although the tabs 16 are shown as extending along substantially the full length of the container body 1, is also possible that smaller tabs could be provided only in the regions above the apertures 14. As the container body 1 is received within the lid 2, these tabs 16 are folded down towards the side walls of the container body 1. There is sufficient space between the lid 2 and the container body 1, and sufficient flexibility in the two components, to allow the protrusions 12 of the lid 2 to pass over the folded down tabs 16 as the lid 2 is pressed down, and the protrusions 12 engage with the apertures 14 in the container body.

The free edges 18 of the folded down tabs 16 are located adjacent the apertures 14 in the container body 1. The free edges 16, therefore, engage with the protrusions 12 on the lid 2 to help to retain the lid 2 in position and resist removal of the lid 2 from the container body 1. The additional resistance provided by the tabs 16 means that the engagement of the protrusions 12 with the apertures 14 need not be sufficient, on its own, to retain the lid 2 and container body 1 together. As such, the protrusions 12 on the lid 2 need not be so large as would otherwise be the case, which simplifies manufacture of the lid 2. The container body 1 as shown is formed of paperboard. It may be preferable for the paperboard to comprise some form of barrier coating or film layer to prevent the ingress of fats or liquids that could damage the container integrity. Alternatively, the container body 1 could be formed of a thin plastics material.

The lid 2 shown in Figure 2 is vacuum formed from a plastics material.

The container body 1 of the preferred embodiment is formed form a flat blank 20 of paperboard, shown in Figure 3, which is folded and secured in shape to form the finished container body 1. The blank 20 can be joined together in such a way that it can be part formed and then folded flat for shipping, as shown in Figure 8, before being finally assembled to form the container body 1 of Figure 1 in store. The formation of the container body 1 from the blank 20 is shown in Figures 3 to 8. Starting from the flat blank 20 of Figure 3, the end walls 6 are folded in to lie flat against a central, substantially rectangular, base panel 22 to the position shown in Figure 4. End wall panels 24, provided at the outer corners of the end walls 6, are then folded back at diagonal fold lines 30 to lie against the folded end walls 6 as shown in Figure 5. Next, side wall panels 26 provided at the ends of the side walls 4 are folded to lie flat against the side walls 4 as shown in Figure 6.

The side walls 4 are then folded inwardly at fold lines provided between the side walls 4 and the base panel 22 to reach the configuration shown in Figure 7. The side wall panels 26 (not visible in Figure 7) now overlie the end wall panels 24, and the side wall panels 26 and end wall panels 24 are bonded together in the regions where they overlap. Finally, the tabs 16 are folded back against the sidewalls 4 as shown in Figure 8. This is possible because of cut lines 28 provided between the tabs 16 and side wall panels 26 (see Figure 3).

This folded blank 20 shown in Figure 8 can be opened up from its flat position to form the container body 1 of Figure 1. The bonding of the side wall panels 26 and end wall panels 24, together with the fold lines 30 between the end wall panels 24 and the end walls 6, mean that the side and end walls 4,6 stand up as the container 1 is opened out. To finally form the container, tabs 32 provided on the side wall panels 26 are inserted into slots 34 at the base of the end walls 6 (see Figure 3).

It may be preferable if the tabs 16 are secured to the side walls 4 in some way, such as through the application of a glue dot to the side wall 4, to hold the tabs 16 in their folded configuration once the blank 20 is folded as shown in Figure 8. This avoids the need for the flaps 16 to be folded, or re-folded, when the container 1 is to be used, and thus simplifies the assembly of the container body 1 and lid 2. The glue dot or other fixing means could readily be applied to the blank 20 during production before the folding process begins.

Figure 9 shows an alternative container body 101 according to the present invention. The container body 101 of Figure 9 is similar in many respects tot eh container body 1 shown in Figure 1. The notable exception is that instead of a single long tab 16 being provided at the top of each side wall 4 of the container body 1, the container body 101 of Figure 9 has two separate smaller tabs 116 provided at the top of each side wall 104. Each smaller tab 116 is provided in the region of an aperture 114 in the side wall 104, and it should be clear that more or fewer tabs 116 of a similar type could be provided, especially if more or fewer apertures 114 were provided in a side wall 104.

The container body 101 can be formed from a blank very similar to the blank 20 shown in Figure 3, using similar steps as described above with reference to Figures 3 to 8. The invention is not considered to be limited to the specific preferred configurations described above.