Package of flexible material, particularly for sterilisable food products

The present invention relates to a packaging of a flexible material according to the preamble of claim 1, particularly suitable for containing food products in a liquid or slurry state or in a solid state with a preserving liquid intended for subjecting to thermal treatment in an autoclave, such as jams, fruit juices and the like. However, the packaging according to the invention can also be used for containing granular or solid products, not necessarily of the edible type.

[0002] While remaining in the sector of liquid, sterilizable food products to which the present invention is particularly addressed, these products are now packaged in hermetically sealed cans or aluminum trays.

[0003] These types of packaging have various drawbacks, ranging from relatively high costs, through the complexity of the manufacturing and filling processes of packaging, to the difficulties associated with opening them. European patent application EP-A-1679269 discloses a package according to the preamble of claim 1.

The object of the present invention is to overcome the above-mentioned disadvantages by providing a package of elastic material that is simple and cheap to manufacture, as well as easy to open.

[0005] Another object of the present invention is to provide such a package that is capable of guaranteeing the absolute sterility of the products contained therein.

[0006] These objects are achieved by the package according to the invention, which has characteristics

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The appended independent appended claims detailed in patent 1.

[0007] Preferred embodiments of the invention are described in the dependent claims.

[0008] Typically, the flexible packaging material is multilayer and comprises at least one inner layer of aluminum having a barrier function or another barrier layer, such as a silicon dioxide or alumina coated polyester layer, and in a similar manner the elastic closing panel material is multi-layered and it contains a peelable inner layer to allow easy opening sealing.

[0009] The sealing of the panel to the circumference of the opening formed in the package follows a path that is disposed on both sides of the edge of said opening so that the heat from the heat sealing causes the inner layer to soften, which "overlaps" the edge of the opening, covering the edge of the layer with aluminum.

[0010] In this way, any contact between the liquid or viscous product contained in the package and the aluminum layer that would cause oxidation or corrosion is avoided and the sterile conditions inside the package are ensured.

[0011] The flexible packaging is preferably obtained from a continuous coil which is previously cut into the die at regular intervals to obtain the above-mentioned openings closed by the flap and sent to the shaping mandrel, which can take the form and type of filling to make it around forming the packaging and filling it with the product.

In particular, the package according to the invention has four longitudinal seals, such as fin type seals, or even inner-to-inside seals, on the four longitudinal edges of the package, seals that serve to give

The package is of rigid consistency, one of which also serves to longitudinally close the coil, forming a pipe.

[0013] The packaging is then finished using two transverse seals and folding them into a pleated fan.

[0014] In the use position of the shaped package, the above-mentioned longitudinal seals are arranged horizontally, forming perpendicular edges of the lower and upper surfaces that stiffen the package and allow the package to remain in a stable upright position, with a peelable patch on the upper surface.

For example, the flexible packaging film according to the invention preferably consists of four layers disposed from the outside in the following order: a first layer of non-oriented polypropylene (CPP), a hot-sealing biaxially oriented polypropylene (BOPP) or a poly (terephthalate) heat-sealed foil. ethylene oxide); a second layer of aluminum; a third layer of polyethylene terephthalate or nylon; the fourth layer of non-oriented polypropylene.

[0016] On the other hand, the window closure film may be three-layered and may comprise, again from the outside: polyethylene terephthalate, aluminum, non-oriented or peelable polypropylene film.

[0017] Further characteristics of the invention will be further refined by the following detailed description, referring to a purely exemplary and therefore non-limiting implementation, illustrated in the accompanying drawings, where:

Figure 1 is an axonometric view of a package according to the invention, shown in the use position, with the optional re-closing lid;

Fig. 2 is a plan view from above of the package shown in Fig. 1, without a lid;

PZ / 1339 / AG Fig. 3 is a sectional view taken along the line III-III shown in Fig. 2;

Fig. 4 shows an enlarged detail of the letter A in Fig. 3;

Figs. 5 to 8 schematically illustrate the successive stages of the process for making a package according to the invention.

[0018] With reference to the above-mentioned drawings and now in particular to Fig. 1, the reference numeral 1 indicates the package according to the invention as a whole, particularly for sterilizable food products in liquid or semi-liquid state, possibly containing solid pieces.

The package 1 has the shape of a parallelepiped box and has a (rectangular) base 2, a top wall 3, a front wall 4, a rear wall 5 and two side walls 6 and 7.

[0020] A rectangular opening or window 8 is formed on the top wall 3, which is closed by the peelable sheet or panel 9, in a way that will later be more precisely described.

[0021] Peripherally to the base 2 and the top wall 3 there is a respective protruding edge 10, obtained by sealing the edge of the film constituting the package, as will be described below, and serving to give the package stiffness and stability.

[0022] Of course, in an alternative embodiment, the edge 10 may be absent.

[0023] A possible manufacturing process for a package according to the invention will now be described with reference to Figures 5 to 8, and should be understood as completely schematic. In fact, in the aforementioned figures, and in particular in Figure 6, the step of forming the window 8 and closing this window with the panel 9 is shown when the package is practically formed and only its closure is missing. In fact, the windows 8 are preferably cut out on the die on a roll of material sheet in regular

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These are spaced and closed by the panels 9 before the packaging is formed, i.e. before the embodiment shown in FIG. 5, in which the coil of material has been closed to form a tube and schematically illustrated already cut to the correct length to form the package 1.

[0024] As shown in Fig. 1, four longitudinal seals 11 of the fin type seals in which the inner edges of the foil are contacted and sealed are formed on a web of material which is produced first along a mandrel usually vertically oriented. One of these longitudinal seals 11, shown by thickening in Fig. 5 to distinguish it from other seals, closes the web of the material sheet to form a tube.

Next, a lower transverse seal 12 (Fig. 6) is formed, which closes the tube from below, followed by the bending of the fan 14 (Fig. 7) and finally by a further transverse seal of the upper surface 13 and by a further bending of the fan 15 (Figure 8) to close the package.

[0026] In a molded mandrel, around this form and whose type of practice if the package 1 has a filling, in which the package is filled during manufacture, when the transverse seal 13 is formed to close the package, then the lower transverse seal 12 is formed in at the same time on the packaging immediately following it, which is then separated by cutting from the preceding packaging.

The shaped package is then placed in a use position, as shown in Fig. 1, in which the above-mentioned longitudinal seals 11 form upper and lower peripheral peripheral edges 10 of the package 1, with two fan bends 14 and 15, which are arranged in this way, to form the respective side walls 6 and 7.

[0028] Referring now particularly to FIGS. 1 to 4, the method of applying a panel 9 to close the opening 8 will be better described.

[0029] As shown by using a gray surface in the figures 1 and 2, the panel 9 is sealed to the top wall 3 of the package 1 along the sealing path 20 which is located on both sides of the circumferential edge of the opening 8. In this way, the heat that the surface of the sheet 9 undergoes during heat sealing causes the material to soften on the surface of the sealing path 20 not overlapping the wall 3 under this path, and said material covers the inner edge of the hole 8.

This situation is schematically illustrated in an exaggerated manner in the enlarged section illustrated in Fig. 4, where the flexible film of the package 1 is shown as a laminar material composed of four layers, and the film of the peel-off sheet 9 as a laminar material consisting of three layers. layers.

[0031] In particular, by way of example, going from the outside and thus from the top surface to the bottom with reference to Figure 4, the packaging film comprises a first non-oriented polypropylene (CPP) film layer 31, a hot-sealed biaxially oriented polypropylene film ( BOPP) or a heat-sealed polyester (PET); a second layer 32 of aluminum; a third layer 33 of polyester or nylon and a fourth layer 34, again of non-oriented polypropylene film.

The foil sheet 9, on the other hand, contains, again from the outside, i.e. from the upper surface to the bottom, a first layer 91 from polyester, a second layer 92 from aluminum and a third layer 93 from a non-oriented polypropylene film.

[0033] As schematically illustrated in Fig. 4, the melting of the layer 93 from CPP polypropylene foil 9

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During hot sealing, this "overflows" this material to the inner edge of the opening 8, and in particular covering the aluminum layer 32, preventing the contents of the package 1 from contact with the edge of the aluminum layer, thus preventing any possible oxidation or corrosion. that could harm the sterility of the contents of the package.

[0034] As previously described, in fact, the packaging according to the invention is particularly suitable for containing sterilizable products, namely products which, after packaging, can be subjected to a thermal treatment in an autoclave.

[0035] Therefore, the materials of the flexible films used to make the package 1 of the sheet 9 are so resistant to high temperatures are suitable for being used to open the pulling of the edges of said flap selected to be sterilized.

[0036] If the package does not have to be heat treated, it is in the case where it is intended for containing non-sterile products into a variety of polyethylene film layers instead of polypropylene or polyester.

[0037] Fig. 1 illustrates schematically like packages 1 by lifting and airfoil 9 and by removing the ability to peel a heat-formed seal along a path 20.

[0038] After removing the panel 9, the content of the package 1 can be consumed even by directly collecting the contents from the package, for example using a spoon.

[0039] Optionally, the lid 40 for covering the package 1 can be placed on the top wall 3, where the sheet 9 is located, for reasons of hygiene, and may optionally be used to close the package again in case of partial consumption of its contents.

[0040] The cover 40 shown in Figure 1 consists of a rectangular wall reproducing the shape of the top wall 3 of the package 1, with a downwardly directed circumferential edge 41 that surrounds the protruding upper edge 10 of the package. .

The sealing of the cover is provided by two oppositely directed tongues 42 (only one can be seen in FIG. 1) which are inserted into the respective fan-shaped folds 14 and 15 provided on the side walls 6 and

7 packages.

The lid 40 may be made of cardboard, plastic or other materials. Alternatively, it may be made of a material of heat-shrinkable plastic that adheres to the top peripheral edge of the package from the outside.

[0043] However, it is clear that the invention is not limited to the particular embodiment previously described and illustrated in the attached figures, but may be subjected to numerous modifications regarding details within the reach of a person skilled in the art, thus without departing from the scope of the invention as submitted in the attached claims.

PZ / 1339 / AG EP 2 174 886 B1