EP0607062B1 - Plastic package for long-shelf-life foodstuffs and method of making same - Google Patents

Description

The invention relates to a plastic packaging for food with a long shelf life at room temperature and to a process for its manufacture.

It is aimed, in particular, at such packaging which is very suitable for packaging in the factory and under excellent aseptic conditions for a food which it is desired to be able to reheat in the packaging in a double boiler or using a microwave oven". If a package of this type, known from WO-A-92/03355, is satisfactory in that it allows, on the one hand, to consume the heated food in the package itself, - without risk of burns - And in that it comprises, on the other hand, a cover which protects the closure lid of the container enclosing the food, it is relatively difficult to manufacture insofar as it must be produced by deep thermoforming of a sheet of composite material, that is to say a technique that is both expensive and whose production rates are not suited to those of high-throughput food packaging plants. In addition, the packaging according to the aforementioned International Application does not include means giving the consumer the assurance that the lid has not been separated from the container in an unauthorized manner to give access to the contents of the container between its release from plant and the consumption of its contents, as generally desired for human food products and, even more strictly, for infant food.

It is therefore a general object of the invention to provide a plastic packaging for food with a long shelf life at room temperature which, while having the qualities of known packaging, does not have the disadvantages of cost and production rate on the one hand, and which on the other hand, can be fitted with tamper-evident indicators.

It is, in this regard, an object of the invention to provide such packaging which, not only is economically acceptable in cost and production rate but which, in addition, is advantageous in terms of marketing. labeling and its presentation at points of sale.

It is also an object of the invention to provide a process for the manufacture of such packaging.

A plastic packaging comprising a container with a bottom and a side wall having, opposite said bottom, an annular sidewalk which provides a sealing area on which a closure cap is sealed, and a cover attached to the container, above said container. cover which it encloses, is characterized, according to the invention, by the characteristics indicated in the second parts of independent claims 1 and 11.

Such a connection can be welding, bonding, riveting or the like.

In a preferred embodiment, the lid is secured to the container by a discrete number of breakable tamper-evident indicators.

Advantageously, the tamper-evident indicators consist of pairs of ears projecting radially from the periphery of the lid and of the container itself or of a member fixed to the latter.

According to another characteristic of the invention, the ears of the container or of the member which is integral therewith and those of the cover are linked together by ultrasonic welding, that is to say a technique which migrates the plastic material from one ear to the other, ensuring a solidarisation particularly effective lid and container which guarantees the breaking of the packaging.

In one embodiment, the container is shaped according to a cup and is produced from a sheet of composite plastic material, advantageously of the polypropylene / EVOH / polypropylene type.

When the packaging is provided with four pairs of ears, which preferably bear a statement indicating their mode of breakability for the separation of the lid and the container, provision is made to position, by locating it in relation to said ears, a label of identification of the contents of the packaging, on the one hand, and to use said ears for the grouping of a plurality of packages in a carton or the like for delivery and presentation at points of sale, on the other hand .

A method according to the invention allows manufacturing at a high rate, which can be of the order of about 60 units per minute.

• la figure 1 est une vue de dessus d'un récipient constitutif d'un emballage selon l'invention ;
• la figure 2 est une vue en coupe selon la ligne II-II de la figure 1 ;
• la figure 3 est une vue de dessus d'une jupe de l'emballage ;
• la figure 4 est une vue en coupe selon la ligne IV-IV de la figure 3 ;
• la figure 5 est une vue d'un couvercle d'emballage selon l'invention ;
• la figure 6 est une vue en coupe selon la ligne VI-VI de la figure 5 ;
• la figure 7 est une vue partielle, en coupe et à plus grande échelle, d'un emballage terminé.

The invention will be better understood from the following description, given by way of example and with reference to the appended drawing in which:

• Figure 1 is a top view of a container of a package according to the invention;
• Figure 2 is a sectional view along line II-II of Figure 1;
• Figure 3 is a top view of a skirt of the package;
• Figure 4 is a sectional view along the line IV-IV of Figure 3;
• Figure 5 is a view of a packaging cover according to the invention;
• Figure 6 is a sectional view along line VI-VI of Figure 5;
• Figure 7 is a partial view, in section and on a larger scale, of a finished package.

A plastic packaging for food with a long shelf life at room temperature intended, - without this indication having any limiting nature whatsoever - to be consumed preferably hot without having to be transferred from said original packaging comprises a container 10, Figures 1 and 2, in the general shape of a dish or soup dish in the embodiment described and shown, and whose capacity can be between 100 and 250 g. The container 10, the opening 11 of which is bordered by an annular sidewalk 12 thus has a bottom 13, a side wall 14 cut along a flat 15, and on the top face 16 of the annular sidewalk 12, a sealing area of a closing cover 17. The container 10 is advantageously made from a sheet of simple plastic material, or preferably from a composite sheet, allowing it to be heated in a water bath or using a micro oven. -waves, on the one hand and which, on the other hand, has "barrier" properties preventing gas exchange to ensure the product enclosed in the container 10 a very long shelf life at room temperature (equal to or greater than 12 months), an example of such a composite sheet being a polypropylene / EVOH / polypropylene complex.

The container 10, which has just been defined, is associated with a cover 20, FIGS. 5, 6 and 7, which encloses and protects the cover 17 as long as the cover is not removed from the packaging and which, according to the invention is secured to the container 10 by a permanent connection which can only be broken by being destroyed when the packaging is opened.

In one embodiment, this connection results from the bonding of a flange of the cover and of the sidewalk 12.

In a variant, the cover is fixed to the sidewalk 12 by plastic rivets.

In the embodiment described and shown, this connection involves a weld and is constituted by break-in tamper-evident indicators formed both on said cover and on a skirt 21, FIGS. 3 and 4, fixed to the container 10 by the intermediate sidewalk 12. More specifically, the skirt 21, in the general shape of a ring, comprises a side wall 23 partly cylindrical, -as shown in 28-, and partly frustoconical, -as shown in 29-, this last part connecting by a leave to an annular flange 22 extending in a plane substantially perpendicular to the axis XX of the skirt. The side wall 23 has, at its free edge 24, first radial lugs 25 ₁ , 25 ₂ , 25 ₃ , 25 ₄ arranged at 90 ° from one another and each connected to said wall 23 by one or more bridges 26 ₁ , 26 ₂ , 26 ₃ , 26 ₄ divisible by torsion. Unstacking ribs, such as 27 ₁ , 27 ₂ , 27 ₃ , ... are provided inside the skirt to facilitate handling.

As can be clearly seen in FIGS. 5 and 6, the cover 20 is closed by a disc 31 and its side wall 30, of shape close to that of the side wall 23 of the skirt 21, has, on its free edge 32, second radial ears 33 ₁ , 33 ₂ , 33 ₃ , 33 ₄ shape and arrangement combined with those of the ears 25 and which bear, on their top face, indications 35, written or in the form of pictograms, which explain their mode of use. Similarly to the ears 25, the ears 33 are connected to the wall 30 by bridges 34 ₁ , 34 ₂ , 34 ₃ , 34 _{4 which can be} broken by twisting.

On the inner surface of the side wall 30, and in the vicinity of its free edge 32, the cover 20 is provided with bosses as 36, Figures 5 and 6, which, during assembly, keep the cover away from the rest of assembly to create chimneys like c , the role of which will be explained below.

To make a packaging according to the invention from its constituent elements which have just been described, the skirt 21 is first fixed to the container 10, advantageously by ultrasonic spot welding of the underside of the sidewalk 12 on the flange 22 of the skirt, as shown at 37 in FIG. 7, and then the ears 25 and 33 of the skirt and the cover are secured, preferably also by ultrasonic spot welding, as shown at 38 in this same figure. Such a technique, which migrates the plastic from one ear to the other, ensures a particularly effective joining of the cover 20 and the skirt 21, which guarantees the tampering of the packaging.

A method according to the invention makes it possible to obtain a practical production rate of the order of 60 packages per minute, including the positioning of a positioned label being identified by the ears before the packages are grouped in boxes. where they are held by the ears, ready to be displayed for sale as soon as the box is opened.

A packaging according to the invention also makes it possible, by its skirt 21, to avoid the consumer from burning himself when he eats the contents of the container 10 after heating in a water bath or in a microwave oven. For such use, the cover 17, which is advantageously a composite sheet of polypropylene / aluminum / polyethylene, is first pierced or removed after the cover has been detached from the container and, when the cover is again placed on the skirt. , it is through the chimneys c that the steam generated during heating is evacuated.

Claims (14)

1. A packaging of plastics material comprising a receptacle (10) having a bottom (13) and a side wall (14) having, opposite the said bottom (13), an annular flange (12) which provides a sealing area (16) on which a closing cover (17) is sealed and a lid (20) attached to the receptacle above the said cover which it encloses, characterised in that it comprises a skirt (21) fixed to the said receptacle by means of the said flange (12), the said skirt (21) being provided on its periphery with first radial lugs (25) and in that the cover (20) comprises second radial lugs (33) of a form and size which match those of the first lugs on the skirt, the first and second lugs being connected inter se.
2. A packaging according to claim 1, characterised in that the said fixing of the lugs inter se is a weld or an adhesive connection or a riveted connection.
3. A packaging according to claim 1, characterised in that the fixing of the skirt (21) to the receptacle (10) and that of the lugs inter se is a multi-point ultrasonic weld.
4. A packaging according to one of claims 1 to 3, characterised in that the first and second lugs are divisible indicators of penetration.
5. A packaging according to one of the preceding claims, characterised in that the first (25) and second (23) lugs are each four in number and are regularly spaced from the angular point of view and advantageously bear markings indicating their manner of divisibility for separation of the cover and of the receptacle.
6. A packaging according to one of the preceding claims, characterised in that the receptacle is shaped like a dome and is made from a sheet of composite plastics material of the polypropylene/EVOH/polypropylene type.
7. A packaging according to one of the preceding claims, characterised in that it comprises a label to identify its contents and which is positioned while being marked in respect of the said lugs (25, 33).
8. A packaging according to one of the preceding claims, characterised in that the skirt and the cover have a first and a second lateral wall (23, 30), the said walls being disposed outside the annular flange (12), the said first and second lugs being disposed at one end of the lateral wall.
9. A packaging according to claim 8, characterised in that the first and second lateral walls (23, 30) are frustoconical.
10. A packaging according to claim 9, characterised in that the first and second lateral walls are disposed below the annular flange (12).
11. A method of producing a packaging according to claim 1, characterised in that:

    . after having placed -on the annular collar (22) of the skin (21) which is provided with first radial lugs (25) on its periphery - the flange (12) of the receptacle (10) filled with a food product and closed by the cover (17), the collar (22) of the skirt is fixed to the flange on the receptacle,

    . on the sub-assembly thus formed is placed the cover provided with second radial lugs (33) of a shape and disposition to match those of the said first lugs on the skirt, and

    . the lugs on the skirt and those on the cover (20) are fixed to one another.
12. A method according to claim 11, characterised in that both the fixing of the skirt (21) to the receptacle (10) and that of the lugs (25, 33) to one another is achieved by multi-point ultrasonic welding.
13. A method according to claim 11, characterised in that fixing of the skirt (21) to the receptacle (10) and/or that of the lugs to one another requires an adhesion.
14. A method according to claim 11, characterised in that fixing of the skirt (21) to the receptacle (10) and/or that of the lugs to one another is achieved by a riveting or the like.

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