Food packaging

Abstract

The invention relates to a packaging for foodstuff comprising: a cardboard tray (74) having a base and four walls erected two by two opposite said base, said four erected walls defining four vertices (76, 78, 80, 82) delimiting an opening; a transparent film (110) connected to said four vertices (76, 78, 80, 82) to close said opening. The two vertices (76, 78) of two opposite walls among the four erected walls each comprise a foldable edge (54, 56), the two foldable edges being folded towards each other; and said transparent film (110) is secured to said two folded edges (54, 56). Figure to be published with the abstract: Fig. 5

Description

Title of the invention: Packaging for foodstuffs

[0001] The present invention relates to a packaging for foodstuffs allowing the foodstuffs contained inside the packaging to be viewed from the outside.

[0002] One area of ​​application envisaged is in particular, but not exclusively, that of the packaging of fruits and vegetables.

[0003] It is known to package perishable goods in cardboard trays. The trays have a base and four walls erected two by two opposite the base. The walls are connected laterally to each other and thus form a cavity suitable for receiving the goods. The four erected walls thus define four peaks which delimit an opening.

[0004] It is known to close the trays by means of a lid made of a transparent polymer material. The lid then covers the tops of the four walls. Usually, the lid is provided with lugs adapted to engage in slots made in the edges of the tray to be able to keep the lid in a fixed position on the tray.

[0005] Such a solution is relatively expensive since the lid must be made independently of the tray by thermoforming. And consequently, such a tray has a high carbon footprint.

[0006] Another solution consists of inserting the tray longitudinally, once filled with food, inside a sleeve made of transparent polymer film and pinching and welding the two ends on each side of the tray. This solution requires a large quantity of polymer film and has the same drawbacks as the previous one.

[0007] It is also known to provide a transparent film having adhesive borders, and to apply it to the four tops of the four walls of the tray to close the opening. The adhesive borders are folded against the four walls on the outside to be stuck there. Thus, the transparent film is integral with the tray and it closes the opening, while the perishable goods are visible from the outside through the transparent film.

[0008] The implementation of such a film is relatively complex to mechanize.

[0009] Also, a problem which arises and which the present invention aims to solve is to provide a cheap and easy to mechanize packaging.

[0010] In order to solve this problem, there is proposed, according to a first object, a packaging for foodstuff comprising: a cardboard tray comprising a base and four walls erected two by two opposite said base, said four erected walls defining four vertices delimiting an opening, and a film transparent connected to said four vertices to close said opening.

[0011] And the two tops of two facing walls among the four erected walls each comprise a foldable edge, the two foldable edges being folded towards each other; and said transparent film is secured to said two folded edges.

[0012] Thus, a characteristic of the invention lies in the implementation of two foldable edges in the two tops of two facing walls to be able to fold them towards each other and extend a film from one of the two tops to the other to secure it to the folded edges. As will be explained in more detail in the remainder of the description, such a design for closing the opening of the tray is both easy to implement mechanically and economical.

[0013] Furthermore, the number of erected walls of the cardboard tray is not limited to four. In particular, a tray with four main walls and four secondary walls extending respectively between the main walls is envisaged.

[0014] Advantageously, and according to the invention, said two folded edges each define an internal face located opposite said bottom and an opposite external face, said transparent film being secured to said external faces. In other words, the two external faces of the two folded edges extend substantially in the same plane and it is easy to apply the transparent film flat to the two external faces after having coated them with an adhesive. For example, a hot-melt glue is applied to the two external faces.

[0015] Furthermore, and according to a particularly advantageous embodiment of the invention, said two vertices comprising a foldable edge are substantially bent towards each other to cause tension in said transparent film. Thus, the two vertices of the two facing walls are bent towards each other while the transparent film retains them in this state. And since the walls are originally flat, the two vertices are under stress and they tend to want to move away from each other. And in this way, they exert tension on the transparent film which is then flat. Such a characteristic makes it possible to perfectly view the food contained inside the tray without deformation due to the transparent film.

[0016] Preferably, the cardboard used to make the tray is a double-sided corrugated cardboard. In other words, it has fluted paper sandwiched between two sheets of smooth paper. Consequently, it has significant bending stiffness, ensuring a relatively high restoring force on the transparent film when it is bent.

[0017] Furthermore, according to the invention, said foldable edges have respectively two opposite ends coming to bear on the tops of the two other facing walls. In this way, the foldable edges are held in abutment against the tops by means of the transparent film which connects them. Consequently, the transparent film is itself held in a fixed position and does not obstruct the view of the food from outside the tray.

[0018] Also, each of the vertices of the other two facing walls advantageously has, according to the invention, two opposite corners and a notch in each of said corners. In this way, the deflection of the two vertices of the facing walls can be increased. Therefore, greater tension is exerted in the transparent film. Consequently, the transparent film remains taut despite the significant deformations undergone by the tray during its transport.

[0019] Furthermore, and according to a particularly advantageous embodiment of the invention, said four walls are of general isosceles trapezoidal shape and have a small side connected to said bottom to form a conical tray. Consequently, the trays can be shaped beforehand and stacked for storage.

[0020] According to another object, in accordance with the invention, there is provided a cardboard blank for producing a package as described above. It comprises: a central panel having two first sides opposite each other and two second sides opposite each other; two first panels respectively hinged on said two first sides and two second panels respectively hinged on said two second sides; and it comprises two edges respectively hinged on said first panels along a fold line, each opposite said central panel.

[0021] Also, according to the invention, said two second panels advantageously each have two opposite cut angles.

[0022] Furthermore, said two edges each have two ends opposite each other extending respectively beyond said fold line.

[0023] Furthermore, the blank according to the invention comprises two times two tabs respectively articulated opposite one another on said two first panels. As will be explained below, the two times two tabs make it possible to hold the walls together laterally. They are preferably glued.

[0024] According to yet another object, in accordance with the invention, a method for packaging foodstuff is proposed. It comprises the following steps: a) a transparent film and a blank as described above are provided; b) said two first panels and said two second panels are erected relative to said central panel to form a tray comprising a bottom and four walls erected two by two opposite said bottom, said four erected walls defining four vertices delimiting an opening, two vertices of two opposite walls respectively comprising said articulated edges; c) said tray is filled with foodstuff; d) said edges are folded towards each other; and, e) said transparent film at said folded edges.

[0025] Preferably, the panels are connected to each other by means of the aforementioned tabs.

[0026] Also, a hot melt glue is advantageously deposited on the folded edges before applying a transparent film. In this way, the transparent film adheres to the folded edges after the glue has cooled.

[0027] According to a preferred characteristic of the invention, before step e), said two vertices comprising said articulated edges are brought together, and the vertices are kept close together during step e). In other words, the two vertices of the two folded edges are brought together before the transparent film is secured there. Then, the film is secured there. Then said two vertices are released, which then puts the film under tension.

[0028] Other features and advantages of the invention will emerge from reading the description given below of a particular embodiment of the invention, given for informational purposes but not as a limitation, with reference to the appended drawings in which:

[0029] [Fig.l] is a schematic top view of a blank according to the invention;

[0030] [Fig.2] is a schematic perspective view of an element of the invention obtained thanks to the object of [Fig.l];

[0031] [Fig.3A] is a schematic top view of the object of [Fig.2] in a first phase of the method according to the invention;

[0032] [Fig.3B] is a rear schematic view of the object of [Fig.3A];

[0033] [Fig.4A] is a schematic top view of the object of [Fig.3B] in a second phase of the method according to the invention;

[0034] [Fig.4B] is a rear schematic view of the object of [Fig.4A];

[0035] [Fig.5] is a schematic top view of the object of [Fig.4B] in a third phase of the method according to the invention; and,

[0036] [Fig.6] is a flowchart of the steps of the method according to the invention.

[0037] [Fig.l] shows, seen from above, a blank 10 cut from a cardboard plate corrugated and allowing a tray to be formed as will be explained below. The blank 10 extends in a longitudinal direction D, and over a length of between 250 mm and 300 mm in the example presented here. It has a first face 12 oriented towards the front of [Fig.l] and a second opposite face 14 oriented towards the rear of [Fig.l].

[0038] The corrugated cardboard used is a double-sided cardboard where a fluted paper is engaged between two sheets of flat paper. The fluted paper has a thickness of between 1 mm and 2 mm. Obviously, a corrugated cardboard of another shape and having other dimensions can be used depending on the needs.

[0039] Thus, the blank 10 comprises a central panel 16 of rectangular shape. This panel central 16 has two first small sides opposite each other 18, 20 and two first large sides opposite each other 22, 24.

[0040] The blank 10 also comprises two large panels 26, 28 respectively hinged, opposite one another, on the first two large opposite sides 22, 24, and two small panels 30, 32 respectively hinged opposite one another on the first two small opposite sides 18, 20.

[0041] It will be observed that the two large panels 26, 28 are symmetrical to each other with respect to a longitudinal center line, while the two small panels 30, 32 are symmetrical to each other with respect to a transverse center line.

[0042] In addition, the two large panels 26, 28 are of isosceles trapezoidal shape. They thus have two second small sides respectively common with the two first large opposite sides 22, 24 and two second large sides 34, 36 opposite and parallel.

[0043] They also have, one of the two large panels 26, two first inclined sides 38, 40 along which two first tabs 42, 44 are hingedly mounted, the other of the two large panels 28, two second inclined sides 46, 48, along which two second tabs 50, 52 are hingedly mounted.

[0044] Furthermore, the two large panels 26, 28 have two edges 54, 56 respectively articulated on the two second large sides 34, 36, which large sides 34, 36 respectively form two fold lines.

[0045] The two edges 54, 56 each have two opposite ends 58, 60 which extend projecting beyond the two second large sides 34, 36. Their projecting extensions are in the form of circular segments.

[0046] As regards the two small panels 30, 32, they are also of general isosceles trapezoidal shape. They respectively have two opposite free edges 62, 64 respectively parallel to the first two small sides 18, 20.

[0047] It will be observed that the distance which extends respectively between the free edges 62, 64 and the first two small sides 18, 20 is substantially equal to the distance which extends between the two second large sides 34, 36 of the two large panels 26, 28 and the two corresponding first large sides 22, 24.

[0048] According to one embodiment of the invention, the distance between the first two large sides 22, 24 is 80 mm, while the distance which extends between the first two small sides 18, 20 is 150 mm. And the distance which extends respectively between the free edges 62, 64 and the first two small sides 18, 20 is 60 mm. According to this embodiment, the two borders 54, 56 have a width of 20 mm.

[0049] The dimensions of the different elements of the blank 10 of this embodiment are obviously not limiting.

[0050] Furthermore, the two small panels 30, 32 each have two opposite cut angles 66, 68.

[0051] Furthermore, it will be observed that the blank 10 is cut from the corrugated cardboard sheet so that the grooves are oriented in a direction perpendicular to the longitudinal direction D of the blank 10.

[0052] We will now refer to both the flowchart of [Fig.6] and the side 10 of [Fig.l]. Thus, in a first step 70, the first two tabs 42, 44 are raised towards the front of [Fig.l] relative to the large panel 26, along the first two inclined sides 38, 40 and the second two tabs 50, 52 are also raised towards the front of [Fig.l] relative to the other large panel 28 along the second two inclined sides 46, 48.

[0053] In addition, the first 42, 44 and second 50, 52 tabs are coated with an adhesive on the second face 14 of the blank 10, i.e. at the rear. Preferably, the adhesive is a hot-melt polymer, for example a polyamide or a polyester.

[0054] In a second step 72, the two large panels 26, 28 are erected relative to the central panel 16, then the two small panels 30, 32 so that they come to rest respectively against the first 42, 44 and second 50, 52 tabs, on their coated face.

[0055] A tray 74 is thus formed as illustrated in [Fig.2]. On the one hand, there is the central panel 16 forming a base and on the other hand, the two large panels 26, 28 and the two small panels 30, 32 which then form two large walls and two small walls respectively facing each other. The two large walls thus define two large peaks 76, 78 and the small walls define two small peaks 80, 82.

[0056] We also find the two borders 54, 56, respectively at the top of the two large walls. They extend respectively in the planes defined by the two large panels 26, 28.

[0057] Also, at the tops 80, 82 of the small walls we find the free edges 62, 64 of the two small panels 30, 32. We also find the two opposite ends 58, 60 of the two borders 54, 56 which extend projecting beyond the two free edges 62, 64 respectively.

[0058] Thus, the tray 74 defines a housing 84 having an opening 86 delimited by the four vertices 76, 78, 80, 82.

[0059] Furthermore, it will be observed that the two opposite cut angles 66, 68 of the blank 10 form a notch 88 in each upper corner of the tray 74.

[0060] The tray 74 thus formed is, in a third step 90, subjected to filling. Thus, foodstuffs 85 are poured through the opening 86, for example, into the housing 84 that it defines.

[0061] In this way, a tray 74 filled with foodstuffs 85 is obtained, such as as illustrated in [Fig.3A].

[0062] Then, in a fourth step 92, the tray 74 is driven in its longitudinal direction following the arrow F, relative to a pair of upper guide ramps 94, 96 and to a pair of lower guide ramps 98, 100 shown schematically in [Fig.3A].

[0063] [Fig.3B] shows the tray 74 seen from the front and, on the one hand, the pair of upper guide ramps 94, 96 and, on the other hand, the pair of lower guide ramps 98, 100.

[0064] Thus, as the tray 74 is driven along the arrow F through the pair of upper guide ramps 94, 96, the two edges 54, 56 are progressively driven to pivot towards each other along the arrows T and -T, around the two fold lines formed respectively by the two second large sides 34, 36.

[0065] Concomitantly, the lower guide ramps 98, 100 which are applied against the two large walls formed by the two large panels 26, 28, under the two fold lines formed respectively by the two second large sides 34, 36, exert stresses according to the arrows R, -R and cause the two peaks 76, 78 to move towards each other. Consequently, these two large walls flex substantially. The amplitude of the movement of the two peaks 76, 78 is increased by virtue of the notches 88. Also, by virtue of the orientation of the grooves, the walls flex perpendicular to these grooves. In this way, the resistance to bending is greater, and the return forces will be all the greater, as will be explained below.

[0066] Also, the two edges 54, 56 are driven to pivot by substantially more than 90° and their two opposite ends 58, 60 come to bear respectively on the two opposite free edges 62, 64, as illustrated in [Fig.4B]. Thus, the two edges 54, 56 are held in a fixed position against the opposite free edges 62, 64. They have an internal face corresponding to the first face 12 of the blank 10, oriented opposite the central panel 16 forming a bottom, and an external face corresponding to the second face 14 of the blank 10 and oriented towards the outside.

[0067] Furthermore, the two vertices 76, 78 remain close to each other. Therefore, the two edges 54, 56 are also maintained in a position in which they are substantially close to each other.

[0068] Also, as illustrated in [Fig.4A], in a fifth step 102, while keeping the two edges 54, 56 close to each other by means of the lower guide ramps 98, 100, not shown, a hot-melt adhesive 104 is applied to the external face of the two edges 54, 56 by means of two injection nozzles 106, 108. The hot-melt adhesive 104 is applied over the entire length of the two edges 54, 56.

[0069] As the adhesive 104 is applied, a strip of transparent film 110 made of a polymer, for example biodegradable, is unwound. For example, transparent and biodegradable polyester films exist.

[0070] The transparent film 110 has a width substantially equal to the maximum width of the tray 74 and it is compressed onto the adhesive 104.

[0071] As it cools, the hot melt adhesive seals the transparent film 110 simultaneously on both edges.

[0072] The strip of transparent film 110 is then cut transversely when a length corresponding to the maximum length of the tray 74 has been unwound. Reference will be made to [Fig. 5] showing the tray 74 seen from above after the strip of transparent film 110 has been cut.

[0073] Also, the stresses exerted according to the arrows R, -R on the vertices 76, 78, then remain for a short time by means of the lower guide ramps 98, 100, so as to allow the cooling of the adhesive and perfect sealing of the transparent film 110 on the two edges 54, 56.

[0074] After this short moment, of a few seconds, the moving tray 74 leaves the lower guide ramps 98, 100, and the two peaks 76, 78 are released. In this way, the two large bent walls formed by the two large panels 26, 28 tend to return to their original shape and thus exert in return a tension on the transparent film 110 in two opposite directions T, -T, by means of the two edges 54, 56. The return forces imparted by the two large panels 26, 28 are relatively significant thanks to the orientation of the grooves mentioned above.

[0075] In this way, the transparent film 110 extends along a plane and thus offers an undistorted view of the foodstuffs contained inside the tray 74.

[0076] According to a particularly advantageous embodiment of the invention, at least one 54 of the two edges 54, 56, at one of its ends 60, has an elongation 55 shown in broken lines on the side 10 of [Fig. 1]. In addition, the fold line formed by the large side 34 between the edge 54 and the large panel 26 is a perforation line.

[0077] The extension 55 is found in [Fig. 5], at the end 60 of the edge 54. Thus, the extension 55 forms a tab which extends freely beyond the edge of the transparent film 110. In this way, opening the tray is facilitated by grasping the tab and exerting sufficient traction on it to tear the edge 54 along the fold line.

Claims

Claims

1. Packaging for foodstuff comprising: - a cardboard tray (74) comprising a base (16) and four walls erected two (26, 28) by two (30, 32) opposite each other with respect to said base, said four erected walls defining four vertices (76, 78, 80, 82) delimiting an opening (86); - a transparent film (110) connected to said four vertices (76, 78, 80, 82) to close said opening (86); characterized in that the two vertices (76, 78) of two opposite walls among the four erected walls each comprise a foldable edge (54, 56), the two foldable edges being folded towards each other; and in that said transparent film (110) is secured to said two folded edges (54, 56).

2. Packaging according to claim 1, characterized in that said two folded edges (54, 56) each define an internal face located opposite said base (16) and an opposite external face, said transparent film (110) being secured to said external faces.

3. Packaging according to claim 1 or 2, characterized in that said two vertices (76, 78) comprising a foldable edge are substantially bent towards each other to cause tension in said transparent film (110).

4. Packaging according to any one of claims 1 to 3, characterized in that said foldable edges (54, 56) respectively have two opposite ends (58, 60) bearing on the tops (62, 64) of the two other facing walls (30, 32).

5. Packaging according to any one of claims 1 to 4, characterized in that each of the vertices (80, 82) of the two other facing walls has two opposite corners and a notch (66, 68) in each of said corners.

6. Packaging according to any one of claims 1 to 5, characterized in that said four walls (26, 28, 30, 32) are of general isosceles trapezoidal shape and have a small side connected to said base (16) to form a conical tray (74).

7. Cardboard blank for producing packaging according to any one of claims 1 to 6, characterized in that it comprises: - a central panel (16) having two first sides opposite each other of the other (22, 24) and two second sides opposite each other (18, 20); - two first panels (26, 28) respectively hinged on said two first sides (22, 24) and two second panels (30, 32) respectively hinged on said two second sides (18, 20); and in that it comprises two edges (54, 56) respectively hinged on said first panels (26, 28) along a fold line (34, 36), each opposite said central panel (16).

8. Blank according to claim 7, characterized in that said two second panels (30, 32) each have two opposite cut angles (66, 68).

9. Blank according to claim 7 or 8, characterized in that said two edges (54, 56) each have two opposite ends (58, 60) from each other extending respectively beyond said fold line.

10. Blank according to any one of claims 7 to 9, characterized in that it comprises two times two tabs (42, 44; 50, 52) respectively articulated opposite one another on said two first panels (26, 28).

11. Method for packaging foodstuffs, characterized in that it comprises the following steps: a) providing a transparent film (110) and a blank (10) according to any one of claims 7 to 10; b) erecting said two first panels (26, 28) and said two second panels (30, 32) relative to said central panel (16) to form a tray comprising a base and four walls erected two by two opposite said base, said four erected walls defining four vertices (76, 78, 80, 82) delimiting an opening (86), two vertices (76, 78) of two opposite walls respectively comprising said articulated edges (54, 56); c) filling said tray (74) with foodstuff (85); d) folding said edges (54, 56) towards each other; and, e) securing said transparent film (110) to said folded edges (54, 56).

12. Packaging method according to claim 11, characterized in that before step e), said two vertices (76, 78) comprising said articulated edges (54, 56) are brought closer to each other, and the vertices are kept close together during step e).

Images