GB2041884A

GB2041884A - Cartons

Info

Publication number: GB2041884A
Application number: GB8000419A
Authority: GB
Original assignee: BEMROSE UK Ltd
Current assignee: BEMROSE UK Ltd
Priority date: 1979-02-22
Filing date: 1980-01-07
Publication date: 1980-09-17

Abstract

A carton of the kind which is erected from a scored blank of card has a tray with a base (1) and side walls (2, 3, 4, 5), and a lid (7). The lid is securely attached around its periphery to the side walls so as to hold the side walls upright. The carton may form a wholly sealed impervious foodstuffs container, and access to the contents of the container may be obtained by removal of a central portion of the lid, for example, by tearing along perforations (13). <IMAGE>

Description

SPECIFICATION Cartons This invention relates to cartons of the kind, hereinafter referred to as the kind described, which are formed by erection from a carton blank of card or other stiff or semi-stiff sheet material which is appropriately shaped and provided with fold lines as for example by scoring.

With a carton of the kind described which is in the form of a tray having a base and upstanding side walls, in accordance with conventional carton erection techniques, the side walls may be held in upright disposition by glueing of folded corner. structures between ends of adjacent side walls. Also a lid may be provided for attachment over the tray whereby a closed container suitable for use as a storage receptacle for foodstuffs or the like may be formed.

With this arrangement, however, it will be appreciated that formation of the closed container involves a number of steps, namely: erection of the blank, glueing of the corner structures, and attachment of the lid. Formation of such container may therefore involve undue expense and/or inconvenience.

An object of the present invention is to provide a carton in the form of a closed container which can be formed in a convenient and inexpensive manner.

According to the invention therefore there is provided a carton of the kind described in the form of a tray having a base and upstanding side walls, and a lid attached to upper peripheral portions of said side walls, characterised in that the attachment of the said lid to said peripheral portions acts to hold said side walls securely in said upstanding position thereof.

With this arrangement it will be appreciated that formation of the carton need involve essentially only two steps: erection of the carton blank and attachment of the lid. Formation of the carton can therefore be effected in a simple, convenient and inexpensive manner.

The lid is preferably integral with the tray and extends from and is formed in one piece with the upper peripheral portion of one said side wall. In this way, the entire carton may be formed from a single, flat carton blank.

Upper peripheral portions with which the lid is not formed in one piece may be turned over to form a lip or rim and the lid may be attached to same by glueing or heat sealing, preferably the latter.

Preferably, the side walls extend along all sides of the base and adjacent side walls are joined to each other and to the base by folded corner structures, and all inner surfaces of the tray are formed from an impervious material or are provided with an appropriate impervious coating or skin, so that the tray can be used as a leakproof receptacle. Also, the lid may be sealed around its entire periphery relative to the said upper peripheral portions, and may be formed from or covered with an impervious material whereby the carton may be used as a wholly sealed, leak-proof container suitable, for example, as a container for foodstuffs. By appropriate selection of the material which the inner surfaces of the carton are formed from or covered with, the carton may be used as a container in which foodstuffs may be cooked in an oven.Card coated with an inner polyester skin is a particularly suitable material for the carton when it is to be used for cooking foodstuffs in a microwave oven.

Such polyester can also be utilised as a heat sealing material for the attachment of the lid to said upper peripheral portions as aforesaid. Card coated with a conventional heat sealing lacquer may be used where the carton is not required to be used in a microwave oven, such lacquer providing a heat sealing medium for attachment of the lid to said upper peripheral portions as aforesaid.

The carton may take any suitable form and in one embodiment has a rectangular base with four strip-shaped side walls coextensive with the respective side edges of the base.

With regard to the lid this may be simply a flat structure which is permanently secured in position and which must therefore be cut or torn to provide access to the contents of the container.

Tc facilitate such access, the lid may be provided with perforations. Alternatively, and particularly in the case where the carton is required to be fully sealed, the lid may be imperforate and printed lines or the like may be provided thereon as a guide to cutting.

The invention will now be described further by way of example only and with reference to the accompanying drawings in which: Fig. 1 is a plan view of a blank for use in forming one form of carton according to the invention; and Fig. 2 shows the carton in a semi-erected state.

As shown in Fig. 1 the carton is formed from a flat blank of a semi-stiff card material which is coated with a thin transparent skin of a fluid impermeable polyester material.

The blank is shaped to define a rectangular base region 1, four side wall regions 2, 3, 4, 5, projecting from and coextensive with side edges of said base region 1, four corner structures 6 connecting the ends of adjacent side wall regions with each other and with the corners of the base region 1, a lid region 7 projecting from the edge of one long side wall region 2 remote from the base region, which lid region 7 is rectangular and projects slightly beyond each end of the said side wall edge to which it is connected, and narrow strip-shaped lip regions 8,9,10 projecting from the edges of the other three side wall regions 3,4,5, remote from the base region 1, the lip regions 8,10, of the short side wall region 3,5, are coextensive with the pertaining side wall edges and the lip region 9 of the long side wall region 4 projects slightly beyond each end of the pertaining edge thereof.

The various regions of the blank mentioned above are separated from each other by scored fold lines 11. Three fold lines 1 2 are also provided in each corner structure 6, said fold lines 12 diverging outwardly from the respective corners of the base region 1.

The lid region 7 is provided with a continuous line of perforations 13 running parallel to and spaced inwardly of the three free edges of the lid region 7 and terminating at each end level with the fold line 11 separating the lid region 7 from the connected side wall region 2.

As can be seen from Fig. 2, the carton blank is erected by folding the side wall regions 2,3,4,5 upwardly (with the polyester coated side of the blank on the inside) and folding the corner structures 6 inwardly in fluted fashion until the side wall regions from upstanding side walls at right angles to the flat base region 1. In this position, the base region 1 and side walls define a tray which is sealed at the base and around the sides thereof by the continuous peripheral arrangement of side walls and fluted corner structures.

The lip regions 8,9,10 are bent outwardly so as to extend parallel to the base region 1 and the lid 7 can then be folded down over the top of the tray to bring the free edges of the lid into alignment with the long free edges of the lip regions 8,9,10.

By application of heat and pressure to the superimposed lid periphery and lip regions, the lid 7 can be securely sealed to the lip regions 8,9,10 the polyester coating of the card material acting as a heat seal medium.

After this heat sealing operation has been effected it will be appreciated that the carton is in the form of a totally sealed container (apart from the perforations) since the lid 7 is sealed around its entire periphery to the upper peripheral portions of the side walls (by connection to the side wall 2 and by heat sealing to the lip regions 8,9,10). Also it will be appreciated that the attachment of the lid 7 to the lip regions 8,9,10 acts to secure the side walls in their upright positions, and indeed such attachment constitutes the only means of securing the side walls in such positions.

With this arrangement it will be appreciated that a sealed container can be formed from a flat carton blank simply by erecting the carton and heat sealing the lid. There is no need for any glueing or other fixing of the corner structures 6 to be effected. Formation of the container can therefore be effected in a particularly simple, convenient and inexpensive manner.

Prior to sealing of the lid in position, the tray defined by the base region and upturned side walls may be filled with foodstuff or other goods and the lid 7 can then be sealed in position.

Subsequently, access to the contents of the container can be had by tearing the central portion of the lid 7 along the perforations 13 so that such central portion can be hinged upwardly.

In the case where the carton contains food, the carton with the contents may be heated in an oven to cook or heat up the food food after the carton is opened. In particular, the carton and contents may be heated in a microwave oven, the polyester coated card used for the carton being particularly suitable for use in this context.

It is of course to be understood that the invention is not intended to be restricted to the details of the above embodiment which are described by way of example only.

Claims

1. A carton of the kind described in the form of a tray having a base and upstanding side walls, and a lid attached to upper peripheral portions of said side walls, characterised in that the attachment of the said lid to said peripheral portions acts to hold said side walls securely in said upstanding position thereof.

2. A carton according to claim 1, wherein the lid is integral with the tray and extends from and is formed in one piece with the upper peripheral portion of one said side wall.

3. A carton according to claim2, wherein the cntire carton is formed from a single, flat carton blank.

4. A carton according to claim 2 or 3, wherein the lid is attached to upper peripheral portions with which the lid is not formed in one piece by glueing or heat-sealing.

5. A carton according to claim 4, wherein said upper peripheral portions with which the lid is not formed in one piece are turned over to form a lip or rim to which the lid is glued or heat-sealed.

6. A carton according to any one of claims 1 to 5, wherein the side walls extend along all sides of the base and adjacent side walls are joined to each other and to the base by folded corner structures.

7. A carton according to claim 6, wherein all inner surfaces of the tray are impervious.

8. A carton according to claim 7, wherein the lid is sealed around its entire periphery relative to the said upper peripheral portion and is also impervious.

9. A carton according to any one of claims 1 to 8, formed from card coated with an inner skin.

10. A carton according to any one of claims 1 to 9, which has a rectangular base and four stripshaped side walls coextensive with the respective side edge of the base.

11. A carton according to any one of claims 1 to 10, wherein the lid has a portion which is bounded by perforations and is intended to be removed to provide access to contentsof-he carton.

12. A carton according to any one of claims 1 to 10, wherein the lid has a portion which is intended to be cut out to provide access to contents of the carton, said portion being bounded by lines providing a guide to cutting.

1 3. A carton substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

14. A carton according to any one of claims 1 to 13, which is sealed and contains foodstuffs.