CH717865B1 - Container for food products. - Google Patents

Abstract

A leak-proof container for food products is defined by an envelope (1), formed of a material containing components chosen from the family of cellulosic materials, and comprising a bottom (2); side and head walls (3) which, in reciprocal combination, surround a product receiving cavity; the side and head walls (3) have an upper edge (4) extending continuously along the contour of the envelope (1); an annular reinforcing element (5), formed of a material containing components chosen from the family of cellulosic materials, associated by overlapping and in surface correspondence with the upper edge (4) of the side and head walls (3) ; a film (6) adhering and associated with the envelope (1) serving to completely cover the internal surface of the bottom (2), the internal surfaces of the side and head walls (3) and the free surface of the annular element ( 5) reinforcement so as to create a layer or skin covering the container (100) to protect and ensure the sealing of the product receiving cavity.

Description

The present invention relates to a container for food products.

[0002] In particular, the present invention is intended for a waterproof container, display stand for perishable products, in particular for food products. Currently, the use of containers (also serving as real trays) for the presentation and sale of food products, such as meat, vegetables, fruits, etc., in stores and supermarkets or hypermarkets is very widespread .

[0003] These trays make it possible, in fact, to define a packaging of a product enclosed in a protected environment (thanks to the use, in general, of a plastic covering film), possibly already weighed and provided with the price of sale.

[0004] The manufacture of these containers has until now followed two different philosophies: – The first consists of manufacturing the container in a single body and in plastic material by a process of injection into molds or thermoforming; – The second of these philosophies is to make the container from a paper material, preferably cellulose, derived from sheets of cardboard, paper or cardboard of different weights, thicknesses and in single layer or multilayer depending on the type of food to contain and its “lifespan”.

[0005] As a general rule, the product contained in the capacity compartment of the container is protected by isolating the compartment from the external environment by means of an insulating barrier associated with the container and by creating an environment under vacuum or with a protective atmosphere inside. inside the compartment.

[0006] The gas barrier serves, essentially, to maintain the gas mixture introduced at the time of packaging inside the container for as long as possible.

[0007] Depending on the partial pressure of the gases in the container, we will experience a leak/entry of gas from the inside to the outside or vice versa.

[0008] Normally, the barrier (preferably to gases and liquids) is obtained by applying to the container a thin plastic film (preferably, but not limited to, a multilayer plastic material of appropriate thickness), which is stretched above the contents of the container, subtended to the edges of the same container and welded or glued continuously to the edges of the same container.

[0009] In the case of containers having strictly flat and smooth edges (such as, for example, the aforementioned plastic containers obtained by thermoforming in a mold), the continuous welding of the film can be easily carried out, so that the insulation of the internal compartment of the container is relatively easy to obtain and maintain over time.

[0010] In the case of the aforementioned containers obtained rather by stamping a flat sheet of cardboard, cardboard paper or another equivalent material (of particular interest in the present development), obtaining a weld of the barrier (a plastic film with a barrier to gases or liquids, or a rigid lid) which is able to ensure the sealing of the container is, however, much more difficult to obtain. In fact, the forming process (e.g. by stamping) is responsible for creating characteristic surface undulations (or grooves) of the material which are mainly concentrated around the concave spatial corners demarcated between two contiguous side walls of the container and around the angles in convex space delimited by the edge of the container and the side walls.

[0011] These undulations are in fact due to local folding and overlapping to which the material constituting the sheet is forced to conform in order to take, from a plane configuration, a configuration in space comprising in particular a surface curved and/or folded side.

[0012] Given that these undulations represent potential channels (capillaries) of intercommunication between the internal compartment of the container and the surrounding external environment, the creation of a localized seal in correspondence with these undulations is very problematic.

[0013] To this end, the Applicant has developed its own technology illustrated in patent documents EP 1 365 964 and EP 1 792 844, which provides a solution, in addition to other problems arising from the annular reinforcement of the container, also to the problem of how to obtain better sealing of containers suitable for their use as airtight containers for fresh food products and/or in any case highly perishable by contact with ambient air.

[0014] This technology provides an improvement to the aforementioned problems through the production of special reinforcing edges which have particular geometric conformations capable of continuously overlapping and enveloping the upper parts of the side walls of the container in order to seek to improve the waterproofing.

[0015] Such a known solution has only given, in industrial practice, partially satisfactory results for current gas-tightness requirements, which require a guarantee of tightness for periods of time that this solution does not. can satisfy.

The aim of the present invention is to provide a container for food products which overcomes the disadvantages of the known technique mentioned above.

[0017] In particular, the objective of the present invention is to provide a container for food products capable of combining high resistance of the cellulose container with a high guarantee of tightness of the packaging gases and the contained product .

Another objective of the present invention is to provide a container for food products at low cost and with a strong ecological and recycling gradient.

[0019] These objectives are fully achieved thanks to a container for food products which is the subject of the present invention, which is characterized by the content of the claims provided below.

[0020] The main characteristics of the invention will appear more clearly in the following description of a preferred embodiment illustrated purely by way of example and not limitation in the attached drawing boards, in which: – Figure 1 indicates a container for food products which are the subject of the present invention, in a schematic plan view seen from above; – Figure 2 shows the container for food products shown in Figure 1 in a schematic side view; – Figure 3 indicates a detail of the container for food products indicated in the preceding figures in a first embodiment and in an exploded schematic side view; – Figure 4 indicates a detail of the container for food products indicated in Figures 1 and 2 in a second embodiment and in an exploded schematic side view.

[0021] With reference to the attached drawings, and in particular with reference to Figure 1, the gas-tight and liquid-tight container which is the subject of the present invention, indicated generally by 100, is used to contain perishable products food type.

As we can also observe in Figures 2, 3 and 4, the container 100 is defined by an envelope 1 formed of a material containing components chosen from the family of cellulosic materials, and comprising a bottom 2.

The envelope also includes side and head walls 3 which, in reciprocal combination, surround a cavity for receiving the products. The side and head walls 3 have an upper edge 4 which extends continuously along the contour of the envelope 1 (said edge 4 has a plane development).

The envelope 1 also comprises an annular reinforcing (and therefore also sealing) element 5 associated by overlapping and in surface correspondence with the upper edge 4 of the side and head walls 3.

The annular element 5 is formed of a material containing components chosen from the family of cellulosic materials.

According to what has just been illustrated, the container 100 further comprises a film 6 adhering and associated with the envelope 1 serving to completely cover the interior surface of the bottom 2, the interior surfaces of the side walls and of head 3 and the free surface of the annular reinforcing element 5 so as to create a layer or covering skin of the container 100 to protect and ensure the sealing of the cavity for receiving the products.

[0027] In other words, the container 100 comprises a combination of components capable of maintaining and increasing the rigidity of the envelope, thanks to the annular element and a component having a gas barrier effect and for liquids which, also thanks to the presence of the annular element, can be placed and associated stably with all the surfaces of the envelope to allow perfect sealing of the entire capacity cavity of the container.

Preferably, the film 6 is formed of a plastic material chosen from the family of thermoplastic polymers (for example, but not limited to, PE, PP, PET) having associations with other polymers and/or or copolymers (e.g., but not limited to, PA or nylon, EVOH) to achieve a multilayer structure with a barrier effect to gases and liquids.

Preferably, the film can be made with polymers coming from fossil sources (non-compostable or compostable) or from renewable sources (non-compostable or compostable) single-layer or multi-layer.

Preferably, the annular reinforcing element 5 comprises an intrados surface 7 folded over the edges of the interior surfaces of the side and head walls 3 and on which the covering film 6 is adhered (see Figures 3 and 4).

[0031] The presence of the intrados surface allows linear coverage of the interior edges of the walls 3 while also covering the corner zones of these same walls 3 where the surface undulations characteristic of the material are concentrated during the formation of the envelope .

[0032] Thanks, therefore, to the intrados surface, we obtain a linear surface with a “gentle” angle towards the annular element 5 remaining able to allow both correct and secure adhesion of the film 6, with reduced risks of rupture of the film 6 during its adhesion to the surface, and a high overall barrier effect of the envelope 1.

[0033] In this context, the annular reinforcing element 5 also comprises an extrados surface 8 projecting outside the upper edge 4 of the container 100 and on which the covering film 6 is adhered (see Figure 4 ).

[0034] The presence of the extrados surface 8 makes it possible to apply the film 6 also beyond the bulk of the edge 4 so as to also obtain, if necessary, on one or more of the exterior curves of the surface a “tab” 11 to facilitate gripping and therefore opening the tray once sealed.

[0035] Furthermore, with this conformation, that is to say with the presence of the tab 11 on the container 100, it is also possible to use the container 100 on different packaging lines.

[0036] In other words, thanks to this technical solution, it is possible to adapt, where appropriate, the container 100 to the dimensions and radii of the sealing molds used in the various packaging lines present on the market.

We will note that the container 100 comprises, when in use, a barrier 9 for sealing the container 100 arranged on the envelope 1 and associated, in correspondence with the upper edge 4, with the covering film 6.

[0038] In this context, the barrier may comprise a film 9 of plastic material made adherent, that is to say associated, to the upper edge 4 of the container 100.

Preferably, the plastic film 9 is heat-sealed on the upper edge 4 so as to be associated with the film or skin 6 covering the envelope 1.

[0040] Thanks to the presence of the covering film or skin 6 and the heat-sealed film 9, the product inside the envelope 1 is optimally protected to be able to guarantee the necessary durability of the product itself.

Preferably, the bottom 2 of the envelope 1 comprises at least one slot 10 open on the outside (which may have different shapes, such as linear, continuous curvilinear or dotted) and closed on the inside of the cavity, by the covering film 6 adhering to the bottom 2.

[0042] In this context, the bottom 2 of the envelope 1 comprises a plurality of slots 10 open to the outside and closed, inside the cavity, by the covering film 6 adhering to the bottom 2.

[0043] The presence of these slots 10 makes it possible to adhere the covering film 6 optimally and safely during the phase of application of the film itself, thanks to the use of an air vacuum system or vacuum (preferably with the simultaneous help of control and adjustment of the temperature above room temperature).

Preferably, the envelope 1 is made from a sheet of material containing components chosen from the family of cellulosic materials which may be the same as the material in which the annular element 5 is formed.

Other layers of material other than cellulose can be applied to this material to increase its physical characteristics.

Preferably, the annular reinforcing element 5 is made with a material containing components chosen from the family of cellulosic materials.

The annular element 5 can be formed of a material different from the material from which the envelope 1 is obtained.

Alternatively, the annular element 5 can be formed of a material similar to the material from which the envelope 1 is obtained. For the annular reinforcing element 5 also, one or more thermoplastic materials are applied, in variable percentages, to its main cellulose component on one or both surfaces of the annular reinforcing element 5 to increase its physical characteristics.

[0049] The present invention also provides an embodiment of a container for perishable food-type products comprising the following steps: – predisposing a flat cutting die formed of at least components chosen from the family of cellulosic materials; – predispose an annular reinforcing element 5 formed of at least components chosen from the family of cellulosic materials; – form an envelope 1, by stamping, starting from the cutting die so as to define a bottom 2, side and head walls 3 which, in reciprocal combination, surround a cavity for receiving the products; the side and head walls 3 have an upper edge 4 which extends continuously along the contour of the envelope 1; – associate the annular reinforcing element 5 on the upper edge 4 of the envelope 1.

Furthermore, before or after the formation of the envelope 1, a step is provided consisting of making at least one slot 10 on the bottom 2 of the envelope 1; and – adhere a covering film 6 along the interior surfaces of the bottom 2, the side and head walls 3 and on the exterior surface of the annular reinforcing element 5.

Preferably, the step of forming the at least one notch 10 on the bottom 2 comprises the formation of a plurality of notches 10 on the bottom 2 itself. Furthermore, the step of producing at least one slot 10 on the bottom 2 of the envelope 1 is carried out before the formation of the envelope 1.

The step consisting of adhering the film 6 to the surfaces of the envelope and of the reinforcing element 5 is carried out using an air vacuum source (passing through the notches 10).

Claims (10)

1. Waterproof container for perishable food-type products defined by an envelope (1), formed of a material containing components chosen from the family of cellulosic materials, comprising: – a base (2); – side and head walls (3) which, in reciprocal combination, surround a product receiving cavity; the side and head walls (3) having an upper edge (4) extending continuously along the contour of the envelope (1); – an annular reinforcing element (5), formed of a material containing components chosen from the family of cellulosic materials, associated by overlapping and in surface correspondence with the upper edge (4) of the side and head walls (3 ), characterized in that it further comprises a film (6) adhering and associated with the envelope (1) serving to completely cover the interior surface of the bottom (2), the interior surfaces of the side and head walls (3) and the free surface of the annular reinforcing element (5) so as to create a layer or skin covering the container (100) to protect and ensure the sealing of the product receiving cavity. 2. Container according to claim 1, in which the film (6) is formed of a plastic material chosen from the family of thermoplastic polymers having associations with PA or EVOH to obtain a barrier effect to gases and liquids . 3. Container according to claim 1 or 2, in which the annular reinforcing element (5) comprises an intrados surface (7) folded over the edges of the interior surfaces of the side and head walls (3) and on which the covering film (6) is adhered. 4. Container according to any one of the preceding claims, in which the annular reinforcing element (5) comprises an extrados surface (8) projecting outside the upper edge (4) of the container (100) and on which the covering film (6) is adhered. 5. Container according to any one of the preceding claims, comprising, during its use, a closing barrier (9) ensuring gas and liquid tightness of the container (100) arranged on the envelope (1) and associated , in correspondence of the upper edge (4), to the covering film (6). 6. Container according to claim 5, in which the barrier comprises a film (9) of plastic material made adherent, that is to say associated with the upper edge (4) of the container (100). 7. Container according to any one of the preceding claims, in which the bottom (2) of the envelope (1) comprises at least one slot (10) open to the outside and closed, inside the cavity, by the covering film (6) adhering to the bottom (2). 8. Container according to claim 7, in which the bottom (2) of the envelope (1) has a plurality of slots (10) open to the outside and closed, inside the cavity, by the film ( 6) covering adhering to the bottom (2). 9. Container according to any one of the preceding claims, in which the envelope (1) is made with a sheet of material containing components chosen from the family of cellulosic materials other than the material chosen for the annular element (5) . 10. Container according to any one of the preceding claims from 1 to 8, wherein the annular reinforcing element (5) is made of a material containing components chosen from the family of cellulosic materials.