ES2342949T3 - CONTAINER INTEGRATED BY A PLASTIC MATTER CONTAINER OBTAINED BY A REMOVABLE OPEN THERMOSELLED IN THE CORRESPONDING CONTAINER. - Google Patents

Abstract

The invention concerns a package (1) comprising a container (10) provided with a surface (12) delimiting an opening (14), and an inner seal (16) sealed on the surface (129 and removable by peeling. The invention is characterized in that: a) the inner seal (16) comprises a support sheet (20) and an extruded (22') or co-extruded (22) plastic layer, forming or comprising a sealing layer (38', 38); b) said extruded (22') or co-extruded (22) layer is made of a material selected to adhere, through its outer surface, to said support sheet (20), and through its inner surface, to said surface (12) when sealed; c) said support sheet (20) is coated on its outer surface with a metal-plated film 21); d) and in that said extruded (22') or co-extruded (22) layer has a thickness Ec selected such that said peeling of the inner seal (16) brings about a coherent rupture of the extruded (22') or co-extruded (22) layer. The invention provides the advantage that said seals enable a broader selection of sealing techniques.

Description

Container composed of a material container plastic sealed by a heat seal removable operculum in the corresponding container.

Field of the invention

The invention relates to the field of packaging constituted by pots or plastic containers that usually contain fresh dairy products, typically yogurts, sealed by opercles.

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State of the art

These opercles are formed from a soft multilayer material comprising a sealing layer and suitable to be sealed, typically by heat sealing, on a surface of sealing of a pot or plastic container, with a view to shut it up. This sealing surface delimits an opening of filling and extraction, and the operculums, once heat sealed in the pot surface, can be separated from the pot by detachment

These opercles can be form opercles pre-cut, is to constitute a hermetic sealing sheet.

Usually for a known type of container containing food products like yogurt and other foods With a limited shelf life, they are put in pots or hermetically sealed plastic containers then with an operculum made from an aluminum foil or Removable paper / PET composite sheet from the surface of the container. The operculums are constituted by a layer of lacquer which produces, during hot sealing of the operculums, the adhesion of the operculum to the container necessary for closure Germ free. When detaching the operculum from the surface of the container, separation occurs at the interface between the sealing agent and the container substrate in the form of adhesive detachment between the lacquered operculum and the surface of the container.

For example, with the patent document CA 1 336 878, hermetic sealing sheets corresponding to the preamble of claim 1 of the annex and intended to seal large rigid plates. These hermetic sealing sheets They have the following structure: PP and PE sealing layer / layer adhesion promoter / barrier material layer, if any completed with a layer of adhesive and a protective layer. These sheets have a sealing layer of about 12 µm and are manufactured by glued laminate of said sealing layer in the material layer of barrier thanks to the adhesion promoter.

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Issues raised

An inconvenience of the current obstacles It is usual to tear during detachment when opening the containers and then only partially detached from the surface. In addition, there is a risk, if the sealing conditions they are not optimal, particularly in the industrial conditions of sealed, that the adhesion to the boundary surface between the layer sealing of the operculum and the substrate of the sealing surface is so small that it can occur, already during transport, a local separation of the operculum and pot surface in the sealing area and thus an unforeseen opening, and even undetectable in certain cases, from the packaging, so that no the content retention period is guaranteed.

The object of the invention is to provide opercles, in the form of airtight sealing sheets in coil or in form of pre-cut operculum stacks, which do not have The aforementioned drawbacks of the operculations made from an aluminum foil or a paper / PET composite multilayer material currently used and comprising a layer of lacquer sealed.

In addition, the object of the invention is opercles economical to manufacture that meet the current directives of Environmental respect for packaging materials.

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Description of the invention

According to the invention, the package comprises a plastic container with a surface that delimits  a filling and extraction opening, the corresponding container containing a product, typically a food product, and a operculum made from a soft hermetic sealing sheet, heat sealing on the surface of the container with help of a layer of sealing and detachable of this by detachment, the corresponding operculum being solidary with the corresponding surface of the corresponding container by means of a cord of sealed, the sealed sealing sheet comprising a support sheet and an extruded layer or a coextruded layer of plastic material, the corresponding extruded layer forming the corresponding layer of sealed, the corresponding coextruded layer comprising a layer which forms the corresponding sealing layer, the corresponding extruded or coextruded layer having an Ec thickness chosen so that the corresponding release of the operculum causes a cohesive rupture of the extruded or coextruded layer, characterized the container so the corresponding extruded or coextruded layer it is formed from a chosen material so that it adheres, by its outer face, to the corresponding support sheet and, for its face inside, to the corresponding surface during the corresponding heat-sealed, and the corresponding support sheet is coated in its outer face of a metallization layer.

The invention also relates to an operculum. intended to be sealed in this package, as well as to a procedure Airtight sealing sheet manufacturing.

The hinges according to the invention solve the issues raised. Indeed, on the one hand, the applicant surprised to see that it was possible to have an extruded layer that guarantee the sealing layer function and contribute in a way important to the thickness of the operculum, as well as its resistance or its "hand", that is to say that the consumer feels manually grab the edge of the operculum with a view to the opening of the sealed container. On the other hand, he could observe at the same time the ease of opening due to operculum detachment and shear force stability, probably thanks to the cohesive rupture of the extruded or coextruded layer, as well as the relative great freedom or tolerance of sealing conditions Hermetic, which is very important in practice. Indeed, he could note that the operculums according to the invention, probably thanks to a fairly large extruded layer thickness, they guaranteed at the same time a great stability of the detachment force and especially a low sensitivity of the final tightness of the containers to heat sealing conditions. Indeed, in particularly in the case where the operculi form a sheet of opercles wide, typically greater than 300 mm, can that there are local pressure differences from the jaws of heat sealing, in the sense of the width of the sealing sheet airtight. Thus, it turned out that the sealing quality of the layer extruded or coextruded was independent of the depth of the annular groove formed by the pressure exerted by a tool sealing during heat sealing.

On the other hand, these obstacles are of economic manufacturing given that an important part of opercle is constituted by an extruded or coextruded layer, of so that at least most of the operculum is a layer extruded or coextruded formed from a thermoplastic material in the least elaborate way, namely in the form of granules

When talking about "cohesive rupture of the extruded or coextruded layer "means that, when taking out by detachment the operculum manufactured from the sheet of operculum according to the invention and sealed against the surface of the opening of a container or continent of plastic material, the material separation occurs inside the layer extruded or coextruded, a part of the extruded layer remaining in the sealing surface of the container and another part on the sheet operculum support.

The structure of the extruded or coextruded layer It is chosen according to the plastic material used for the sheet support and container matter. Indeed, the adhesion between the support sheet and the extruded or coextruded layer on the one hand, and between the extruded or coextruded layer and the container on the other hand, after sealing the operculum on the surface of the container, it has to be superior at least in the parts of the area of sealing determinants for sealing the seal at cohesive adhesion inside the extruded layer or coextruded, to obtain a cohesive rupture of the extruded layer. The layered structure of the extruded or coextruded layer is also choose according to the desired properties for the operculum.

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Description of the figures

Figure 1 is a perspective view of a plurality of packages 1 comprising four continents or plastic containers 10 sealed by hinges 16 sealed and formed from an airtight sealing sheet 17. In one of the containers 10, bottom left, the detachment of an operculum 16 by manually pulling the corner of the operculum or detachment tongue 19. In another of the containers 10, bottom right, operculum 16 has been removed partially in a part of the container 10 in which it is represented the sealing footprint 183 of the sealing bead 18, the operculum 16 being present in the other part where the cord was represented sealing 18.

Figure 2 shows, in enlarged view and in a vertical plane I-I perpendicular to the plane of the operculum, a section of the sealing cord 18 of a container 1 of the Fig. 1, comprising an operculum 16 consisting of a sheet support 20 and an extruded layer 22 'forming the corresponding layer sealing 38 'or by a coextruded layer 22 comprising the corresponding sealing layer 38, the different layers of the corresponding coextruded layer 22 were not represented other than one of the other.

Fig. 3 represents a cross section of an embodiment of a coextruded layer 22 comprising three layers 34, 36 and 38, while Figure 4 represents a cross section of another modality of coextruded layer comprising two layers 34 and 38. In order not to overload the figure, layer 36 was not plumed.

Figure 5 illustrates schematically in cross section analogous to that of figure 3, the manufacture of a hermetic sealing sheet 17 by supply of a support sheet 20 and coextrusion of a layer 22.

In this figure, layers 21 and 40

Figure 6, analogous to the right side of the Figure 5, represents an embodiment of airtight sealing sheet 17 in which the coextruded layer 22 is assembled with a support sheet 20 comprising successively abroad: a primary layer of adhesion 39, a print 41 and a layer of varnish overprint 42. In this figure, layers 39, 40 were not plumed and 42.

Figure 7 is a perspective view of a hermetic sealing sheet coil 17.

Figure 8 represents, in its upper part, a cross-sectional view of a 17 'stack of opercles precut 16 'and, in its lower part, a top view of a 16 'pre-cut operculum printed.

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Detailed description of the invention

According to the invention, the support sheet 20 can be A sheet of plastic material.

When talking about "support sheet", it is done reference in this case to the sheet that is coated on one side of the extruded layer 22 'coextruded 22. However, the support sheet, although preferably constituted by plastic material, also It can include a sheet of paper and / or aluminum. So, you can apply other layers of plastic, aluminum or paper, eventually printed and provided with a protective lacquer, in the other side of the corresponding support sheet 20.

The corresponding sheet of plastic material is It can be made from a plastic material chosen from: a polyester, in particular terephthalate polyethylene (PET), a polyolefin, in particular a polypropylene * (PP), a polyamide (PA) or a cycloolefin copolymer (COC).

The corresponding support sheet 20 is coated on its inner or outer faces with a layer of metallization 21.

Typically, the corresponding layer of metallization 21 can cover the corresponding outer face of the corresponding support sheet 20, as depicted in the figure 5.

The corresponding support sheet 20 can be obtain either from a sheet of the corresponding material plastic supplied in reel, possibly by means of a second extrusion or coextrusion from the corresponding plastic material supplied in the form of granules.

Whatever the method of obtaining the corresponding support sheet, the corresponding support sheet and / or the corresponding metallization layer may comprise, in at least one of its faces, a layer of an adhesion primary 39, 40

The thickness of the support sheet 20 is usually located between about 7 and 200 µm and depends on the volume and weight of the contents of the container to be closed.

According to the invention, the corresponding layer extruded 22 'or coextruded 22 may have an Ec thickness ranging from 5 µm to 80 µm and typically 15 µm to 60 µm.

According to the type of operculum, the corresponding extruded layer 22 'or coextruded 22 may have an Ec thickness that ranges from 25 µm to 40 µm and typically a thickness ranging from 30 \ mum to 35 \ mum.

As illustrated in Figure 3, the layer coextruded 22 may comprise three layers and have a layer of adhesive 34 assembled with the support sheet 20, an intermediate layer 36 and a sealing layer 38 assembled with the surface 12 of the container 10.

However, as illustrated in Figure 2, coextruded layer 22 may comprise two layers and have a adhesive layer 34 assembled with the support sheet 20 and a layer of sealed 38 assembled with the surface 12 of the container 10.

The adhesive layer 34 may contain less one of the following components: copolymers and / or copo1imers  graft and / or terpolymers comprising acidic groups or ionomers, PE metallocene, linear PE, EVA copolymers, EMA copolymers, EEA copolymers, EBA co-polymers, blends of these components or of a polyolefin with a resin sticky

The corresponding layer of adhesive 34 can have a thickness ranging from 2 µm to 10 µm.

The corresponding sealing layer 38 can contain at least one of the following components: copolymer of ethylene and vinyl acetate (EVA), copolymer of ethylene and methyl acrylate (EMA), copolymer of ethanol and acrylate of Butyl (EBA), ethylene and ethyl acrylate (EEA) copolymer, terpolymers with α-olefin monomers that They comprise esters.

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The corresponding sealing layer can comprise at least one of the corresponding components and At least one sticky resin.

The corresponding sealing layer can have a thickness ranging from 5 µm to 7 0 µm and typically from 10 µm to 30 µm.

The corresponding intermediate layer 36 may contain at least one of the following components: polyamide (PA), homo- and polymer and cycloolefin copolymer (COC) copolymers of polyolefins with or without mineral or organic fillers. The intermediate layer 36 may comprise a mineral filler such as talc for example, in a weight ratio that typically ranges from between 5% and 30%, so as to favor the cohesive rupture of the corresponding intermediate layer during the opening of the corresponding container.

Similarly, the corresponding layer of sealed 38, 38 'may comprise a mineral or organic filler, talc for example, in a weight ratio that typically ranges from between 5% and 30%, so as to favor the cohesive rupture of the corresponding sealing layer during the opening of the corresponding container. The corresponding intermediate layer 36 may have a thickness ranging from 2 µm to 40 µm.

According to the invention, the container 10 can be made from a material chosen from: a polystyrene (PS), a polyester (PET), a polyolefin, in particular the polyethylene (PE) or polypropylene (PP), the chlorine polymer of vinyl (PVC).

The corresponding operculum 16 is typically a printed operculum, a printed motif 41 can be formed on one side external of the corresponding support sheet 20 or of the corresponding metallization layer 21 or corresponding layer Primary adhesion 39.

In such a case, an overprint varnish 42 may cover the corresponding printed reason 41.

The corresponding operculum sheet 17 of corresponding operculum 16 may have a thickness ranging from 10 um to 90, the corresponding support sheet 20 presenting a thickness It is and the corresponding coextruded layer 22 presenting a thickness Ec so that the ratio Ec / Es is at least equal to 1 and is typically between 2 and 4.

As illustrated in Figure 2, the corresponding sealing bead 18, formed during the corresponding heat sealing by means of a tool sealed 24, may comprise a narrowed annular central part 180 surrounded by two peripheral tabs 181, 182, a tab inner 181 and an outer flange 182, the corresponding peripheral tabs 181, 182 comprising an excess thickness t 'of the corresponding coextruded layer 22, the corresponding thickness being at least equal to 1.5 Ec.

Another object of the invention is constituted by an operculum 16 intended to obtain, by heat sealing in the corresponding container 10, the corresponding container 1 according to the invention, the corresponding operculum 16 being a part of the corresponding airtight sealing sheet 17 or an operculum precut 16 'of a stack 17' of precut curtains in the corresponding airtight sealing sheet 17.

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Examples of realization

Figures 1 to 8 illustrate examples of embodiment of the invention.

Packages 1 were manufactured according to figure 1.

Fig. 1 shows an arrangement with four plastic pots or containers 10 for the packaging of Fresh products, yogurt for example. In the illustrated example, they assembled four pots 10 with each other. Each pot 10 has a sealing surface 12 surrounding an opening 14 covered with an operculum 15 made from a sealing sheet airtight 17. The operculum sheet 17 was sealed on the surface of sealing 12 according to a sealing cord 18, cord 18 that is only represented below and to the right of figure 1.

The release of operculum 16, as illustrated below and to the left of figure 1 by means of a arrow 44 that symbolizes a manual effort of detachment, gives access to the opening 14 of the pot and allows to remove all or part of the pot content.

The individual pots 10 were assembled by the sealing surface 12, thus forming a plurality of pots sealed, after filling, thanks to an airtight sealing sheet 17 which forms a plurality of operculums 16. To separate the pots 10, common edge edges are provided, which can be separated easily by hand by marked weakening lines or cut into the sealing surface 12, To cover these lines of weakening, hermetic sealing sheet 17 was also cut in individual operculums 16, so that each operculum 16 can be take out individually. Each operculum 16 thus applies freely. on the sealing surface 12 of the pot 10 and sealed according to the sealing cord 18, so that on the outside of this cord of sealed 18, the container 1 comprises a detachment tab 19 at each of the four corners of the sealing surface 12 of each pot 10.

Fig. 2 shows the displacements or material fluences that occur during sheet sealing airtight seal 17 or operculum 16 on the surface of sealed 12 of pot 10 of figure 1. In this same figure also the tear plot, references from S1 to S5, to through the sealing bead 18 during detachment of the operculum 16 when exerting a manual shedding effort 44 in a corner of the operculum to separate it from the sealing surface 12.

Given the high temperature of the sealing tool 24 applied to the airtight sealing sheet 17 and on the sealing surface 12 of the underlying pot 10, tool typically comprising a sealing jaw such As indicated in dashed line in Figure 2, the materials are soften in the sealing zone and the pressure exerted by the sealing tool 24 in operculum 16 leads to formation of a sealing cord 18 that has, in the case of the pots of the Figure 1 and in the plane of operculum 16, the shape of a box with rounded corners.

In cross section, the sealing bead 18 it comprises a narrowed annular central part 180 surrounded by two peripheral tabs 181, 182, an inner flange 181 and a outer flange 182, the corresponding peripheral tabs 181, 182 comprising an excess thickness t 'of the corresponding layer coextruded 22, the corresponding excess thickness being at least equal to 1.5 Ec.

Regarding the sealing surface 12 of pot 10, this comprises an annular groove 26, deep t, which corresponds to the narrowed annular central part 180, and two sealing rings 28 and 29 corresponding to the tabs peripherals 181 and 182 of the sealing bead 18. Indeed, the matter expelled by the formation of slot 26 thus leads to the formation of sealing rings 28 and 29 of both parts of the slot 26. By varying the sealing conditions, you can vary the depth t of the sealing rings 28 and 29, which it can typically range from 0.1 mm to 1 mm, while preserving the sealing tightness.

Regarding the sealing sheet airtight 17 or the operculum 16, with the pressure of the tool sealed 24, the coextruded layer 22 is largely ejected out of the groove 26 on the sealing surface 12 of the pot 10, so that a narrowed annular central part 32 is formed which corresponds substantially to the corresponding annular central part narrowed 180 of the sealing bead 18, and forming tabs concentric rings 30 and 31 with a thickness t 'greater than the thickness Ec of the coextruded layer 22, above the sealing rings 28 and 29.

The sealing cord 18 thus presents, in particular thanks to these displacements of matter, a strong adhesion between the support sheet 20 and the coextruded layer 22, to the time between the coextruded layer 22 and the surface 12 of the pot or container 10, which leads to a great tightness of the cord of sealing 18, in particular in the corresponding sealing areas to references S1 to S5 of Figure 2.

During detachment of the sealing sheet airtight 17 or operculum 16 by manual effort 44 which tends to separate the operculum from the sealing surface 12 of the pot 10 of figure 1, a tear 33 appears, first in the area S1 in the coextruded layer 22, typically in the sealing layer 38, tear that then spreads, from zone S1 to zone S5, until the complete separation of operculum 16, in the form of rupture cohesive

Indeed, the mechanical characteristics of the support sheet 20, in particular the hardness of the materials, are higher than those of coextruded layer 22, so that tearing 33 is propagated by the thickness of the coextruded layer 22.

In the example shown, the sealing sheet airtight 17 has for example a support layer 20 of 12 µm of polyethylene terephthalate (PET) with a coextruded layer 22 with a weight of 30 g / m2 and the pot or container 10 is constituted by polystyrene (PS). In addition, for example, the support sheet 20 can print and provide a protective lacquer with a weight of 1 g / m2.

To form container 1, a sheet of airtight seal 17 comprising the extruded layer 22 'forming the corresponding sealing layer 38 'according to figure 2.

To form container 1, a airtight sealing sheet 17 comprising the coextruded layer 22 according to Figure 3. This coextruded layer 22 comprises three layers: one adhesive layer 34, an intermediate layer 36 and a sealing layer 38. An airtight sealing sheet 17 which comprises the coextruded layer 22 according to figure 4. This coextruded layer 22 It comprises three layers: an adhesive layer 34 and a sealing layer 38.

An airtight sealing sheet was also manufactured 17 as illustrated schematically in Figure 5: supplied a support sheet 20 comprising an outer layer of metallization 21 and an inner layer of an adhesion primary 40, and on this support sheet 20 a layer coextrusion was performed 22 comprising a layer of adhesive 34 intended to adhere to the adhesion primary layer 40, an intermediate layer 36 and a sealing layer 38. Thus the corresponding sealing sheet was obtained Hermetic 17 shown on the right side of Figure 5.

Similarly, the sealing sheet was manufactured airtight 17 of figure 6. In this form of sheet 17, the layer coextruded 22, or extruded layer 22 ', was assembled with a sheet support 20 comprising successively outside: a layer of primary adhesion 39, a print 41 and a varnish layer of overprint 42.

Whatever the sheet mode of airtight seal 17, an airtight seal sheet 17 was obtained in coil form, as illustrated in figure 7.

A 17 'stack of operculi was also formed pre-cut 16 'from hermetic sealing sheet 17 in coil of figure 7.

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Advantages of the invention

The invention has great advantages.

Indeed, on the one hand, the opercles 16, 16 ' according to the invention they can be sealed in pots by means of cords of sealed 18 of variable depth, without this harming the tightness of container 1 or adhesion of the operculum to the pot, which is very advantageous in practice because it increases tolerances Adjusting the sealing tools in industrial line and decreases considerably as the amount of waste and health risks derived from a failure of watertightness of packaging 1.

On the other hand, the invention allows obtaining opercles 16, 16 'or economical hermetic sealing sheets 17 of manufacture to the extent that it is possible to obtain operculums from which a fraction of at least 50% of the thickness or at least minus 50% of the mass, corresponds to an extruded layer 22 'or coextruded 22 formed from plastic material in granules. This fraction can be much higher and reach a 60, a 70, even 80%.

Finally, the invention allows obtaining, at from the same support sheet 20, a whole family of operculums 16, 16 'or airtight sealing sheet 17 by varying the composition of the extruded layer 22 'or coextruded 22, so that it is easy to obtain a great variety of operculums, presenting various properties, both as regards its weight, its "hand", its barrier properties, its adhesion and its strength of detachment or opening force, etc.

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List of references

Container

one

Continent or container

10

Heat sealing surface from 10

12

Filling opening of 10

14

Opercle

16

Opercle precut

16 '

Sealing sheet airtight

17

Operculum stack precut

17 '

Cord sealed

18

Central part narrowed

180

Eyelash inside

181

Eyelash Exterior

182

18 footprint 12

183

Tongue detachment

19

Support sheet

twenty

Layer of metallization

twenty-one

Coextruded layer

22

Extruded layer

22 '

Tool of sealed

24

Annular groove of 12

26

Annular tabs of 12

28, 29

Annular Thicknesses of 22

30, 31

Annular central part narrowed 22

32

18 tear

33

Adhesive layer 22

3. 4

Intermediate layer 22

36

Sealing layer 22

38, 38 '

Primary Adhesion of 20 or 21 (external)

39

Primary Adhesion of 20 or 21 (internal)

40

Print

41

Varnish overprint

42

Manual effort detachment

44

Claims (24)

1. Container (1) comprising a plastic container (10) provided with a surface (12) that delimits a filling and extraction opening (14), the corresponding container containing a product, typically a food product, and an operculum (15) made from a soft hermetic sealing sheet (17), sealed by heat sealing on the surface (12) of the container (10) with the aid of a sealing layer and detachable from it by detachment, the corresponding operculum being integral with the corresponding surface of the corresponding container by means of a sealing cord (18), the hermetic sealing sheet (17) comprising a support sheet (20) and an extruded layer (22 ') or a coextruded layer (22) of matter plastic, the corresponding extruded layer (22 ') forming the corresponding sealing layer (38'), the corresponding coextruded layer (22) comprising a layer forming the corresponding sealing layer (38), the corresponding ca extruded (22 ') or co-extruded (22) having a chosen thickness Ec so that the corresponding release of the operculum (16) causes a cohesive rupture of the extruded (22') or co-extruded layer (22), characterized in that the corresponding extruded layer (22 ') or coextruded (22) is formed from a material chosen so that it adheres, on its outer face, to the corresponding support sheet (20) and, on its inner face, to the corresponding surface during the corresponding heat seal, and the corresponding support sheet (20) is coated on its outer face with a metallization layer (21). 2. Container according to claim 1 wherein the Support sheet (20) is a sheet of plastic material. 3. Container according to claim 2 wherein the plastic material sheet is made from a plastic material chosen from: a polyester, in particular polyethylene terephthalate (PET), a polyolefin, in particular a polypropylene (PP), a polyamide (PA) or a cycloolefin copolymer (COC). 4. Package according to any one of the claims 1 to 3 wherein the corresponding support sheet (20) and / or the corresponding metallization layer (21) comprises, in at least one of its faces, a layer of an adhesion primary (39, 40). 5. Package according to any one of the claims 1 to 5 wherein the corresponding extruded layer (22 ') or coextruded (22) has an Ec thickness ranging from 5 µm to 80 µm and typically 15 µm to 60 µm. 6. Container according to claim 5 wherein the corresponding extruded layer (22 ') or coextruded (22) has a Ec thickness ranging from 25 µm to 40 µm and typically a thickness that goes from 30 µm to 35 µm. 7. Package according to any one of the claims 1 to 6 wherein the coextruded layer (22) comprises three layers and presents a layer of adhesive (34) assembled with the support sheet (20), an intermediate layer (36) and a sealing layer (38) assembled with the surface (12) of the container (10). 8. Package according to any one of the claims 1 to 7, wherein the coextruded layer (22) comprises two layers and presents a layer of adhesive (34) assembled with the support sheet (20) and a sealing layer (38) assembled with the surface (12) of the container (10). 9. Package according to any one of the claims 7 to 8 wherein the adhesive layer (34) contains at least one of the following components: copolymers and / or graft copolymers and / or terpolymers comprising acid groups or ionomeric, metallocene PE, linear PE, EVA copolymers, EMA copolymers, EEA copolymers, EBA copolymers, blends of these components or of a polyolefin with a resin sticky 10. Package according to any one of the claims 7 to 9 wherein the corresponding adhesive layer (34) has a thickness ranging from 2 µm to 10 µm. 11. Package according to any one of the claims 1 to 10 wherein the sealing layer (38, 38 ') It contains at least one of the following components: copolymer of ethylene and vinyl acetate (EVA), copolymer of ethylene and methyl acrylate (EMA), copolymer of ethylene and acrylate Butyl (EBA), ethylene and ethyl acrylate (EEA) copolymer, terpolymers with α-defined monomers that They comprise esters. 12. Container according to claim 11 wherein the corresponding sealing layer (38, 38 ') comprises at least one of the corresponding components and at least one resin sticky 13. Package according to any one of the claims 1 to 12 wherein the corresponding sealing layer (38, 38 ') has a thickness ranging from 5 µm to 70 µm. 14. A container according to claim 7, characterized in that the intermediate layer (35) contains at least one of the following components: polyamide (PA), cyclo-olefin polymer or copolymer (COC), homopolymer or copolymer of polyolefins, with or without mineral or organic loads. 15. Package according to any one of the claims 1 to 14 wherein the corresponding sealing layer (38, 38 ') comprises a mineral or organic load.

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16. Package according to any one of the claims 7 or 14 wherein the corresponding intermediate layer It has a thickness ranging from 2 µm to 40 µm. 17. Package according to any one of the claims 1 to 16 wherein the container (10) is made to from a material chosen from: a polystyrene (PS), a polyester (PET), a polyolefin, in particular polyethylene (PE) or polypropylene (PP), the vinyl chlorine polymer (PVC). 18. Package according to any one of the claims 1 to 17 wherein a printed motif (41) is formed in an external face of the corresponding support sheet (20) or of the corresponding metallization layer (21) or corresponding primary bonding layer (39). 19. Container according to claim 18 wherein an overprint varnish (42) covers the corresponding motif printed (41). 20. Packaging according to any one of the claims 1 to 19 wherein the corresponding cord of sealed (18), formed during the corresponding heat sealing by means of a sealing tool (24), comprises a part narrowed central ring (180) surrounded by two peripheral tabs (181, 182), an inner flange (181) and an outer flange (182), the corresponding peripheral tabs (181, 182) comprising an excess thickness t 'of the corresponding coextruded layer (22), the corresponding over thickness being at least equal to 1.5 Ec. 21. Package according to any one of the claims 1 to 20 wherein the corresponding cord of sealed, formed during the corresponding heat sealing by of a sealing tool, it can comprise a central part narrowed ring surrounded by two peripheral tabs, one tab inside and an outer tab, the corresponding tabs peripherals comprising an excess thickness t 'of the corresponding coextruded layer, the corresponding excess thickness being at least equal to 1.5 Ec. 22. Operculum (16) intended to be sealed by heat sealing on the surface (12) of the container (10) of the corresponding container (1) according to any one of the claims 1 to 21, the corresponding operculum (16) being a part of the corresponding airtight sealing sheet (17) or a pre-cut operculum (16 ') of a stack (17') of pre-cut opercles in the corresponding airtight sealing sheet (17). 23. Procedure for manufacturing a sheet of hermetic seal (17) intended to form the corresponding operculum according to claim 22 or to be part of the corresponding container according to any one of the claims 1 to 21, in which: a) the corresponding support sheet (20), typically in the form of a coil, is supplied, the corresponding support sheet being typically coated with the corresponding metallization layer (21), and a sheet typically chosen among the sheets of: PET, PA, PP, COC, the corresponding sheet having a thickness ranging from 7 µm to
200 µm, b) is applied by coextrusion on the inner face of the corresponding support sheet (20) a coextruded layer (22, 22 ') comprising, inside, the corresponding layer of adhesive (34) intended to adhere to the corresponding support sheet (20) and, on the outside, the corresponding sealing layer (38), the corresponding coextruded layer (22, 22 ') presenting an Ec thickness ranging from 25 µm to 40 µm.

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24. Method according to claim 23 in which the corresponding coextruded layer (22, 22 ') comprises, between the corresponding layers of adhesive (34) and sealing (38), the corresponding intermediate layer (36) whose thickness ranges from 2 µm to 40 µm.