GB2447127A

GB2447127A - A container for snack food

Info

Publication number: GB2447127A
Application number: GB0803287A
Authority: GB
Inventors: Gary Orsman
Original assignee: St Neots Packaging Ltd
Current assignee: St Neots Packaging Ltd
Priority date: 2007-02-28
Filing date: 2008-02-22
Publication date: 2008-09-03
Anticipated expiration: 2028-02-22
Also published as: GB0803287D0; GB2447127B

Abstract

A blank for a container for snack food, the blank comprising card or other foldable material, the blank further comprising: a generally rectangular back wall, the two elongate sides of the back wall each being joined by a hinged fold to at least part of respective side walls; and a generally rectangular base; the blank being able to form an assembled container which is generally triangular prism-shaped; the blank further comprising integral hinge means in the form of a foldable web located between two adjacent walls of the blank, wherein the foldable web is folded such that it projects inside the container when the container is assembled; and a foldable flap provided along substantially an entire edge of the web within the container.

Description

Title: Container for Snack Food

Field of the Invention

The present invention relates to a blank for a container for snack food, the blank being made from paper, cardboard or a similar foldable material; a container formed from the blank; and to a method of making the blank for snack food.

Background of the Invention

The snack food industry has rapidly expanded over recent years due to the increased consumption of pre-prepared and take-away food. Sandwiches are a convenient pre-prepared food which are widely available from various outlets.

One of the problems associated with the preparation and marketing of sandwiches is the relatively short shelf-life of the product. It is important that the sandwiches are as fresh as possible when purchased by the consumer.

In order to increase the shelf-life of the sandwiches, it is necessary to provide a sealed container for the sandwiches. The packaging for sandwiches is often constructed from clear, substantially impermeable, plastics material. Such plastics packaging may be sealed after placing the sandwiches inside the container. The use of plastics material for food packaging usually allows for substantially gas tight sealing of foodstuffs, which prevents the packaged food from dehydrating and preserves freshness. Sandwiches contained in such packaging may have a shelf-life of several days. However, such packaging is usually not biodegradable or recyclable.

An alternative packaging for sandwiches may be prepared from paper or card material, as disclosed in, for example, GB 2,391,212 and WO 02/346299. Such packaging may be sealed to increase the shelf-life of the food within the container. However, such packaging has the disadvantage that it is typically structurally weak. Further, a problem with such packaging is leakage of the sandwich filling. In particular, oily or fatty sandwich fillings (e.g. mayonnaise, butter or the like) may frequently cause the formation of unappetising grease stains on the paper or card packaging. Moreover, existing card packaging allows for gas flow exchange through the packaging, leading to dehydration and curling of sandwiches. Another problem associated with known sandwich packaging is that it permits tampering of the food packaging, and in particular permits tampering in a non-evident manner, especially at the rear sides andlor edges of the package.

W02007/012880 discloses a food container made from a foldable blank of card or the like which, inter alia, aims to improve the degree of sealing around the packaged foodstuff and hence extend shelf life. The document discloses a partially assembled container, formed from a blank, the container having triangular side walls and substantially rectangular walls to enable the formation of a generally triangular prism-shaped container with an opening for receiving the food product, with "hinge means comprising a first hinge part hingedly connected to a second hinge part" provided between one of the side walls and one of the end walls. The hinge means comprises a large generally rectangular flap which, in the assembled container, overlies an end wall, and a generally triangular flap bisected by a fold line, which flap forms a foldable web of card which, in the assembled container, lies adjacent to one side wall and helps to reduce gas flow through the container.

In various embodiments the present invention aims to overcome or reduce one or more of the aforementioned problems.

Summary of the Invention

In a first aspect the invention provides a blank for a container for snack food, the blank comprising card or other foldable material, the blank further comprising: a generally rectangular back wall, the two elongate sides of the back wall each being joined by a hinged fold to at least part of respective side walls; and a generally rectangular base; the blank being able to form an assembled container which is generally triangular prism-shaped; the blank further comprising integral hinge means in the form of a foldable web located between two adjacent walls of the blank, wherein the foldable web is folded such that it projects inside the container when the container is assembled; and a foldable flap provided along substantially an entire edge of the web within the container.

Desirably, the base is provided attached to a first side wall. In the assembled container the two side walls are each preferably essentially triangular, more especially right-angled triangles, preferably isosceles triangles. In a preferred embodiment, the foldable web (when unfolded) is of substantially similar dimensions to a side wall of the container. Preferably, the foldable web is essentially triangular. Desirably the foldable web is located between the lid and the base of the container.

On assembly of the container, the foldable web is generally folded about a central fold line which bisects the foldable web to generate two sections. During partial assembly of the container, one of the sections is typically folded onto the other section and a surface of one section is adjacent to the inner surface of a side wall of the container. Conveniently, part of one section may be adhered to the inner surface of a side wall of the container. This may desirably be achieved by gluing using a conventional adhesive.

The foldable web reduces the flow of gas both into and out of the container to increase the stability and shelf-life of the contents of the container, reducing dehydration of the sandwiches and preserving freshness. In addition, the foldable web prevents or reduces leakage of any fluid or other matter from the container in use.

The foldable flap is typically smaller than the foldable web. Conveniently it takes the form of a relatively narrow flange-like flap extending along substantially the entire edge of the foldable web. Advantageously, the foldable flap further reduces the flow of air into and out of the container.

In a preferred embodiment, the foldable flap forms a sort of secondary' lid or closure over the inside edge of the foldable web which, in addition to reducing the flow of air into and out of the container, also renders the container more tamper-proof than other similar designs, such that a finger or narrow foreign object cannot readily be poked into the container between the foldable web and the lid.

The foldable flap is desirably trapezoidal, with tapered end portions. The foldable flap may simply be folded over the adjacent portion of the foldable web during assembly of the container.

Alternatively, the foldable flap may be glued or adhered in some way to the adjacent portion of the lid and/or the foldable web to assist in closure of the container.

Conveniently further fold lines are preferably provided in the foldable flap. In particular, the fold line in, and bisecting, the foldable web is continued through the foldable flap, forming a central fold line therein, and two further fold lines, forming approximately a 90 angle to one another, are provided from the edge of the foldable flap which abuts the foldable web and which run to the opposite edge. These fold lines each form an angle of about 45 with the first-mentioned central fold line, and assist in placing the foldable flap in a desired conformation when the container is assembled. These folds create at least three sections in the foldable flap: first and second Sections, at opposite ends of the foldable flap, and a smaller, triangular-shaped central section.

In one embodiment during assembly of the container, the first section of the foldable flap may be folded onto and adhered to the second section of the foldable flap, and a surface of the second section is placed adjacent to and optionally adhered to the inner surface of the lid of the container. In this embodiment the third, central, section of the foldable flap is folded about the central fold line, such that the fold line of the third section forms a continuation of the fold line of the foldable web. Typically, the second section of the foldable flap is adjacent to the lid of the container and a surface of the first section is adjacent to the second section when the container is in the closed configuration. This has the disadvantage that multiple thicknesses of card are positioned adjacent the hinge, such that it may be difficult to close and seal the container.

In an alternative, and preferred arrangement, the first section of the foldable flap is folded onto and adhered to a section of the foldable web, and a surface of the second section of the foldable flap is adjacent to and adhered to the inner surface of the lid of the container. In this embodiment, the first section of the foldable flap is enfolded inwards (i.e. towards the body of the container) and the second section of the foldable flap is enfolded outwards, (i.e. away from the body of the container), such that the two sections are folded in opposite directions. In particular, the second section of the foldable flap is adjacent to the lid of the container and the first section is positioned between the two sections of the foldable web. In this embodiment, the third section is folded about the two fold lines provided between the first, second and third sections of the foldable flap, and the central fold line of the third section forms a continuation of the hinged fold between the foldable web and the foldable flap. This has the advantage that the thickness of card adjacent to the hinge is reduced such that less force is required to close the container. Thus, it is easier for a manufacturer to close and seal the container.

Advantageously, the foldable flap further reduces the flow of air into and out of the container. Additionally, the provision of a foldable flap substantially reduces the risk of tampering of the food packaging, and in particular reduces the risk of tampering in a non-evident manner, especially at the rear sides andlor edges of the package.

In a preferred embodiment, the blank further comprises frangible means provided on the foldable web to facilitate the further opening of the assembled container from an open state to an extended state.

The frangible means conveniently comprises a readily rupturable attachment between one section of the web and a side wall of the container and/or between one section of the web and another section of the web. Advantageously the frangible means can be readily ruptured (e.g. by a consumer pulling on the container), allowing the folded web of the container to be unfolded and opened out. This can both facilitate access to, and removal of, the packaged foodstuff when it is to be consumed, and the unfolded web forms an enlarged surface or tray on which the foodstuff can be vested.

In one embodiment, the frangible means is provided on the surface of the foldable web adjacent to the side wall of the container. In another embodiment, the frangible means is provided on the surface of the section of the foldable web which is folded onto the other section of the foldable web. In a further embodiment, the frangible means is provided on both the surface of the foldable web adjacent to the side wall of the container and the surface of the section of the foldable web which is folded onto the other section of the foldable web.

Preferably, the frangible means is adhered to the side wall of the container or other surface of the foldable web by means of, for example, cold-melt adhesive or glue.

The frangible means can include any one or more (in any combination) of the following: weakened portions, regions surrounded by perforations and/or the like. In one embodiment, the frangible means comprises a portion of the blank defined by a perforated boundary. This has the advantage that, in the assembled state, the container is secured and held in position by the adhesive, but that when the assembled container is opened from an open state to an extended state, only that region surrounded by perforations is adhered to the side wall of the container.

Conveniently, the frangible means facilitates the opening of the container to form a tray on which one half of the sandwich may be placed whilst the other half is consumed by a person eating the sandwich.

In a preferred embodiment, part of the foldable web is glued or otherwise adhered to another part of the container (e.g. a side wall or other part of the foldable web) and the area of adhesion is circumscribed by a line of perforations or other form of weakening.

Desirably, the weakened or perforated portion covers a small area of the container. Typically, the weakened or perforated portion has a substantially circular boundary.

In another embodiment, one of the side walls of the container comprises two triangular sections which may be brought into close juxtaposition in the folded conformation to form a side wall.

The triangular sections are typically joined by a hinged fold to the back wall and base of the container, respectively. Preferably, the two triangular sections are essentially half the size of the side wall of the container. Conveniently, a foldable flange is provided at one edge of one of the triangular sections. On assembly of the container, the two triangular sections are brought into close juxtaposition to form a side wall and the foldable flange overlaps with and is adhered to a surface of the other triangular section, thus holding the side wall in position. Advantageously, the provision of a foldable flange which overlaps with one of the triangular sections helps to preserve the freshness of the contents of the container.

Desirably the blank of the invention further comprises a generally rectangular lid portion. This may be joined, typically by a hinged fold, to any suitable portion of the blank. Preferably the lid portion is attached by a hinged fold to the longest edge of one of the triangular side walls.

Advantageously the lid comprises a window portion formed from a transparent or translucent material, such that a snack food inside the container can be viewed by a prospective consumer when the container is assembled. A preferred material for the transparent or translucent portion of the lid is a biodegradable substance, such as a cornstarch film. In one embodiment of the present invention, the window portion may extend over substantially the entire length of the lid, although the window portion may cover a shorter length of the lid.

Preferably, the invention provides a container for snack food having a lid comprising a window portion, which window portion comprises a transparent or translucent film which is substantially free of folds and creases, especially transverse folds or creases. This has the advantage of allowing a prospective consumer to see clearly the food inside the container, especially a sandwich filling. In a preferred embodiment, the window portion extends over at least 35% of the area of the lid, more preferably over at least 40% and most preferably over at least 45% of the area of the lid.

Typically, a foldable flange is provided on the outer edges of one or more (jreferably all) of the side walls, back wall and the base of the container (i.e. those edges which are not hinged to another part of the packaging). Conveniently in assembling the container, the flanges are folded outwards (away from the body of the container) and the lid may be adhered to the flanges, thus forming a seal and closing the snack food container.

In a preferred embodiment, all or at least part of one side of the card or other foldable material (which side forms the inner surface of the assembled container) is provided with a polyethylene coating. When heated, the coating partially melts. Accordingly, the polyethylene-coated card can be heated to seal the lid to the flanged portions of the side and back walls and the base.

In one embodiment, a tab is provided on the lid, preferably at one corner thereof. Conveniently, pressure may be applied to the tab by the consumer to separate the lid from the body of the container, thus opening the container and allowing food to be removed by the consumer.

The container is typically a single use carton and is disposed of after use.

In a second aspect, the invention provides a partially assembled container, which takes the form of a blank in accordance with the first aspect defined above, at least partly folded and glued. The partially assembled container is still substantially flat (for convenient storage) but portions of the blank overlie other portions. The blank is preferably such that the partial assembly can be effected by processing the blank through automated folding/gluing apparatus, of the sort typically employed in industry. Once partially assembled, the container can easily be opened out into a ready-to-use conformation, simply by pulling or pushing (e.g. pushing at opposite ends of the partially assembled container).

Preferably, a container in accordance with the present invention consists substantially or entirely of biodegradable material. The container of the present invention is inexpensive and disposable.

Preferably, the snack food container of the present invention is used to hold one or more diagonally cut sandwich slices. Typically, the snack food container is designed to hold two diagonally cut sandwich slices. Alternatively, the snack food container may be designed to hold three or four diagonally cut sandwich slices. The dimensions of the blank can be adjusted in a manner which will be apparent to those skilled in the art.

According to one embodiment of the present invention, the sandwich slices may be placed on the inner surface of one of the side walls and the packaging may be folded and assembled around the sandwich. Alternatively, the packaging may be folded prior to the insertion of the sandwich. In either event, the lid is sealed as a last step, once the sandwich is placed inside the container.

Preferably, the carton is formed form a single blank.

Advantageously, the container blank may be stored in a flat conformation prior to use, thus minimising the space required to store the packaging.

In accordance with one embodiment, the outer surface of the packaging may be coloured andior printed with labelling. In another embodiment, the outer surface of the packaging may be laminated.

The blank of the present invention advantageously provides a substantially sealed container when in a closed configuration, thereby making it suitable for the storage of food products therein so as to maintain the freshness of the food for an extended time period when compared to existing cartons.

One advantage of the container of the present invention is that it provides, in preferred embodiments, a configuration which lends itself to processing on an automated production line.

More specifically the container can be readily held in an open, assembled configuration, with the lid open, and then transferred to an insertion configuration (in which, for example, a sandwich may more readily be introduced into the container) without requiring any human manipulation.

Typically the container can be held in an open, assembled configuration simply by application of gentle pressure, e.g. by holding the container between two pinch belts or rollers. Preferably this pressure is applied to the respective apices of the side walls at or near (i.e. within 3cm, preferably within 2cm, most preferably within 1cm) the point where they contact the back wall and base. This allows one side wall to be readily opened outwards by the simple expedient of a projecting finger or the like, passage of the container past the finger causing a resistance to the advance of the side wall which is forced outwards, opening the container into an insertion configuration.

Desirably, once opened into this insertion configuration, the container may be deposited into another belt or line, preferably having grooves, apertures, recesses or the like being so shaped and dimensioned as to accept the container and retain it in the insertion configuration. The containers are then advanced past a packing station, at which the contents are inserted into the container. This will normally be done by human operatives, but in principle this step too could also be automated.

The container may then be advanced past another finger or projection to return it to the open assembled configuration, and past a cam, finger or the like to close the lid. With the lid closed, the container may be advanced to a heating station to seal the lid to the rest of the container. In this way, partial opening of the container (to facilitate insertion of the foodstuff) and its closure can be performed in an entirely automated manner.

In accordance with a third aspect, the present invention provides a method of producing a snack food container in accordance with the second aspect defined above or a blank therefor, and in a fourth aspect provides a method of packaging sandwiches using the container of the invention.

Detailed Description of the Invention

The invention will be further described by way of illustrative example, and with reference to the following drawings wherein: Figure 1 shows an underside view of a blank from which a container for snack food can be formed, in accordance with the one embodiment of the invention; Figure 2 is a perspective view of a container for snack food in accordance with a similar embodiment of the invention as shown in Figure 1, wherein the container is in an open, partially extended configuration; and Figure 3 is a perspective view of a container for snack food in accordance with the same embodiment of the invention as shown in Figure 2, wherein the container is in an assembled, open configuration.

With reference to Figure 1, a blank from which a wedge-shaped container for snack food (2) can be formed is shown. The container is predominantly made from cardboard and comprises a generally rectangular back wall (4) having two elongate side edges (6,6') and two short edges (8,8'). The elongate side edges (6,6') and short edges (8,8') are approximately 12cm and 7cm in length, respectively. Generally triangular side walls are provided. One side wall is formed by 10. A further side wall comprises two triangular sections (24, 24') which may be brought into close juxtaposition in the assembled conformation to form a side wall. The triangular sections are joined by a hinged fold to the back wall (4) and to a base (12) of the container. A foldable flange (26) is provided at the edge of one of the triangular sections (24). On assembly of the container, the two triangular sections (24, 24') are brought into close juxtaposition and the foldable flange (26) is adhered to a surface of the other triangular section, thus holding the side wall in position. The base (12) of the container has a length of about 12cm and a width of about 7cm. A foldable web (14a, 14b) is provided adjacent one corner of the container, between the base and one of the side walls (10) of the container. The foldable web (14a, 14b) has essentially the same dimensions as the side walls of the container.

One side of the card (which forms the inner surface of the assembled container) is provided with a polyethylene coating. The triangular side wall (10) is attached to a lid (13) via a fold line provided along the longest edge (11) of the side wall (10). The longest edge (11) of the side wall (10) is approximately 17cm in length. Flange portions (20, 20', 20") are provided on the outer edges of the side wall (formed by 24, 24'), back waIl (4) and base (12). In assembling the container, the flanges (20, 20', 20") are folded outwards (i.e. away from the body of the container). After assembly, the region of the container wherein the lid (13) is in contact with the flanges (20, 20', 20"), is heated to partially melt the polyethylene coating such that the lid (13) is adhered to the flanges (20, 20', 20"), therefore closing and sealing the container. The flange portions (20, 20', 20") are approximately 1cm wide.

During assembly, the foldable web folds about a central fold line (17) which bisects the foldable web to form two sections (14a, 14b) that project inside the container. One section (14a) of the inner surface of the foldable web is adjacent to the side wall (10) of the container. The outer surfaces of the two sections (14a, b) of the foldable web are adjacent to one another in the assembled container.

A region surrounded by perforations (15) is provided on one section (14a) of the foldable web.

The region surrounded by perforations (15) is glued to the side wall (10) in the assembled container.

A foldable flap (16, 16', 16") is provided along substantially the entire length of the foldable web. The foldable flap (16, 16', 16") is smaller than the foldable web and approximately 8cm in length. The foldable flap takes the form of a relatively narrow flange-like flap and is trapezoidal in shape, with tapered end portions. Following assembly, the foldable flap (16, 16', 16") is folded over and adhered to the adjacent portion of the foldable web.

The lid (13) is provided with a window portion (22) formed from a transparent or translucent material, such as a cornstarch film. The transparent film protects the contents of the packaging whilst allowing a prospective consumer to view the interior of the container.

The container is ideally suited to holding a diagonally cut sandwich, wherein two parts of a sandwich are placed next to each other within the packaging. The dimensions of the assembled container (and hence of the unfolded blank) are selected to accommodate the sandwich. The sandwich is placed onto the inner surface of one of the side walls and the packaging is assembled by folding along the relevant fold lines. The packaging is then sealed.

Figure 2 is a perspective view of the wedge-shaped container for snack food in an open, partially extended configuration. The embodiment shown in Figure 2 is similar to that shown in Figure 1, although the foldable flange (26) shown in Figure 2 is larger than the foldable flange (26) shown in Figure 1. The container is formed from a blank and when assembled, the foldable web is folded about a central fold line (17) which bisects the foldable web to form two sections (14a, l4b), such that the inner surface of one section is adjacent to the inner surface of one of the side walls (10) of the container, and the outer surface of the two sections (14a, 14b) of the foldable web are adjacent to one another. The foldable web reduces the flow of gas into and out of the container to keep the contents of the container fresh and increase the shelf-life thereof.

A foldable flap extends along the edge of substantially the entire length of the foldable web (i.e. along the edge of both sections (14a, 14b) thereof. Further fold lines are provided in the foldable flap. In particular, the fold line (17) in, and bisecting, the foldable web is continued through the foldable flap, forming a central fold line (32, best seen in Fig. 1), and two further fold lines (30, 30'), forming a 900 angle, are provided from the edge of the foldable flap which abuts the foldable web and which run to the opposite edge. These fold lines (30, 30') each form an angle of 450 with the first-mentioned fold line (17), and assist in placing the foldable flap in a desired conformation when the container is assembled. These folds create at least three sections in the foldable flap: first and second sections (16, 16") at opposite ends of the foldable flap, and a smaller, triangular shaped central section (16'). The first and second sections (16, 16") of the foldable flap have essentially the same dimensions and are approximately 8cm in length. The third section (16') has three sides, two sides having a length of approximately 2cm, and a third side having a length of approximately 2.5cm.

During assembly of the container, a first section (16) of the foldable flap is folded onto and adhered to the second section (16") of the foldable flap, and a surface of the second section (16") is placed adjacent to and adhered to the inner surface of the lid (13) of the container. The third central section (16') of the foldable flap is foldedabout the central fold line (32), such that the fold line in the third section forms a continuation of the fold line (17) in the foldable web. The second section (16") of the foldable flap is adjacent to the lid of the container and a surface of the first section (16) is adjacent to the second section (16") when the container is in the closed configuration.

In an alternative arrangement, the first section (16) of the foldable flap is folded onto and adhered to a section (14b) of the foldable web, and a surface of the second section (16") of the foldable flap is adjacent to and adhered to the inner surface of the lid (13) of the container. The first section (16) of the foldable flap is enfolded inwards (i.e. towards the body of the container), and the second section (16") of the foldable flap is enfolded outwards (i.e. away from the body of the container), such that the two sections are folded in opposite directions. The first section (16) of the foldable flap is adjacent to the lid (13) of the container and the second section (16") is positioned between the two sections (14a, 14b) of the foldable web.

The region surrounded by perforations (15) provided on the foldable web is adjacent and adhered to the inner surface of one of the side walls (10) of the container when the container is in the assembled configuration. The region surrounded by perforations (15) is circular in shape and small in area, such that when assembled, the foldable web is adhered to the side wall (10), but when the container is opened out to the extended state, only the region surrounded by perforations (15) remains adhered to the side wall (10), therefore facilitating the opening of the container.

The container is provided with a lid (13). Foldable flanges (20, 20' 20") are provided on the outer edges of the side wall (formed by 24, 24'), back wall (4) and base (12). In assembling the container, the flanges (20, 20', 20") are folded outwards.

Figure 3 is a perspective view of a snack food container in an assembled, open configuration, in accordance with the same embodiment shown in Figure 2. One side of the card (which forms the inner surface of the container) is provided with a polyethylene coating. Once assembled, the region of the container wherein the lid (13) is in contact with the flanges (20, 20', 20") is heated sufficiently to cause the polyethylene coating to partially melt such that the lid (13) is adhered to the flanges (20, 20', 20"), thus closing and sealing the container. The foldable flap is secured in position to further minimise gas flow within the container and to reduce the risk of tampering of the food packaging.

The container shown in the drawings may conveniently be transferred between an open, assembled configuration and an insertion configuration in an automated manner. For example, the container may be held in a first conveyance between two pinch belts or rollers which pinch the side walls near their respective apices or near the point where they contact the back wall and base, with the lid (13) open, the aperture of the container preferably facing upwards or towards the direction of travel of the container (or at an intermediate position therebetween). A finger or projection contacting the side wall (10) will force the side wall (10) to open outwards as the container advances, typically causing the side wall (10) and base (12) to rotate through approximately 90 , causing the container to adopt an insertion configuration.

Conveniently, the container may at this juncture be transferred to a second belt or other conveyance, typically situated below the pinch belts or rollers and running at an angle thereto (e.g. perpendicular). Advantageously the container is dropped or deposited Onto the second belt or other conveyance, which is preferably provided with a plurality of grooves, apertures, recesses or the like which are so shaped and dimensioned so as to accept a container and retain it in the insertion configuration. In this configuration the container is advanced past a packing station at which a sandwich or other snack food is placed into the container. Advancement of the container past further suitably positioned fingers or projections: returns the container to the open, assembled configuration; and closes the lid. The lid is then heat-sealed to the rest of the container at a sealing station.

Those skilled in the art will appreciate that the "handedness" of the blank illustrated in the drawings may be reversed without substantially affecting the invention. Arrangements which allow for automated handling and processing of the blank are preferred. Thus, for example, in Figure 2, panel 10 and lid 13 could be transposed with foldable web 14; and/or panels 24 and 24' could be transposed etc.

Claims

Claims 1. A blank for a container for snack food, the blank comprising

card or other foldable material, the blank further comprising: a generally rectangular back wall, the two elongate sides of the back wall each being joined by a hinged fold to at least part of respective side walls; and a generally rectangular base; the blank being able to form an assembled container which is generally triangular prism-shaped; the blank further comprising integral hinge means in the form of a foldable web located between two adjacent walls of the blank, wherein the foldable web is folded such that it projects inside the container when the container is assembled; and a foldable flap provided along substantially an entire edge of the web within the container.
2. The blank of claim 1, wherein the base is attached to a first side wall.
3. The blank of claim 1 or 2, wherein in the assembled container the two side walls are each substantially triangular.
4. The blank of any one of claims 1, 2 or 3, wherein the foldable web, when unfolded, is of substantially similar dimensions to a side wall of the container.
5. The blank of any one of claims 1 to 4, wherein the foldable web is essentially triangular.
6. The blank of any one of claims 1 to 5, wherein on assembly of the container, the foldable web is generally folded about a central fold line which bisects the foldable web to generate two sections.
7. The blank of any one of the preceeding claims, wherein during assembly, one section of the foldable web is folded onto another section of the foldable web.
8. The blank of claim 6 or 7, wherein part of one section is adhered to the inner surface of a side wall of the container.
9. The blank of claim 8, wherein the foldable flap is foldable over the adjacent portion of the foldable web.
10. The blank of claim 8 or 9, wherein the foldable flap is folded over and adhered to the adjacent portion of the foldable web.
11. The blank of any one of the preceding claims, wherein further fold lines are provided in the foldable flap.
12. The blank of claim 11, wherein the further fold lines create three sections in the foldable flap: first and second sections, at opposite ends of the foldable flap, and a smaller, triangular shaped central section.
13. The blank of claim 12, wherein a first section of the foldable flap is folded onto and adhered to a second section of the foldable flap, and a surface of the second section of the foldable flap is adhered to the inner surface of the lid of the container.
14. The blank of claim 12, wherein a first section of the foldable flap is folded onto and adhered to a section of the foldable web, and a surface of a second section of the foldable flap is adjacent to and adhered to the inner surface of the lid of the container.
15. The blank of any one of the preceding claims, wherein frangible means are provided on at least one of the two sections of the foldable web to facilitate the further opening of the assembled container from an open state to an extended state.
16. The blank of claim 15, wherein the frangible means comprises a readily rupturable attachment between one section of the web and a side wall of the container andlor between one section of the web and the other section of the web.
17. The blank of claim 15 or 16, wherein the frangible means is adhered to the side wall of the container or other surface of the foldable web by means of cold-melt adhesive or glue.
18. The blank of any one of claims 15 to 1 7, wherein the frangible means covers a small area of the container.
19. The blank of any one of claims 15 to 18, wherein the frangible means has a substantially circular boundary.
20. The blank of any one of the preceding claims, wherein one of the side walls of the container comprises two triangular sections which are brought into close juxtaposition in the assembled conformation to form a side wall.
21. The blank of claim 20, wherein a foldable flange is provided at one edge of one of the triangular sections and wherein, on assembly of the container, the two triangular sections are brought into close juxtaposition to form a side wall and the foldable flange overlaps with and is adhered to a surface of the other triangular section, thus holding the side wall in position.
22. The blank of any one of the preceding claims, comprising a generally rectangular lid portion.
23. The blank of claim 22, wherein the lid is joined by a hinged fold, to any suitable portion of the blank.
24. The blank of claim 22 or 23 wherein the lid comprises a window portion formed from a transparent or translucent material.
25. The blank of any one of the preceding claims, wherein a foldable flange is provided on the outer edges of one or more of the side walls, back wall and the base of the-container.
26. The blank of claim 25, wherein in assembling the container, the flanges are folded outwards, away from the body of the container, and the lid is adhered to flanges, thus forming a seal and closing the snack food container.
27. The blank of any one of the preceding claims, wherein all or at least part of one side of the card or other foldable material is provided with a polyethylene coating.
28. A container formed from a blank in accordance with any one of the preceding claims.
29. The container in accordance with claim 28, wherein the container consists substantially or entirely of biodegradable material.
30. The container in accordance with claim 28 or 29, wherein the container provides, in preferred embodiments, a configuration which lends itself to processing on an automated production line where the container can be readily held in an open, assembled configuration, with the lid open, and then transferred to an insertion configuration (in which, for example, a sandwich may more readily be introduced into the container) without requiring any human manipulation.
31. A container as hereinbefore described and with reference to the accompanying drawings.
32. A blank as hereinbefore described and with reference to the accompanying drawings.