EP0276606A1 - Sealed container, especially for alimentary use - Google Patents

Abstract

A container, especially for food use, such as a tray (1), comprising an element forming a body (2) provided with an upper rim (3) of non-circular shape and an element forming a lid (4) having a groove (5) intended to receive the said rim (3) in its base, and comprising a channel (6) radially external to the said groove (5), projecting under the latter towards the inside of the said body and coming into contact with the said rim (3) at the level of the end (9) of the latter in the closure position of the container. The channel (6) has a depth (h) which is smaller in the portions with a small radius of curvature, such as the portions forming an angle (A), than in the lateral portions (L) of the lid (4) with a larger radius of curvature or which are substantially rectilinear. The invention applies especially to the foodstuffs industry. <IMAGE>

Description

The present invention generally relates to a container for food use in particular, and essentially relates to a tray of the type comprising a body element provided with an upper rim of non-circular shape and a cover element having a groove intended to receive at its bottom. said ledge.

The invention finds particular application in the food industry and in particular for the preparation of vacuum packed dishes intended to be reheated in their packaging before consumption.

In the case of a particularly thermoformed tray, the technique of vacuum packaging of food products requires the use of a perfectly sealed cover. When the upper rim of the tray body is circular, there is no particular problem. However, when this rim is of non-circular shape, it is difficult to simultaneously obtain a good seal and an ease of opening.

Thus, it has already manufactured substantially rectangular trays, with rounded corners which are perfectly sealed. However, it is impossible to open such trays without damaging the lid; which leads to a poor presentation of the product.

To solve this problem, that is to say ensuring both a perfect seal of the container and a clean and easy opening thereof, we used a additional plastic film forming a seal, placed between the container lid and its body. Such a film, in order to seal the container, is generally made of a complex multilayer plastic material, and requires an additional heat-sealing or self-adhesive operation on the body of the container.

When the total seal is not reached, the shelf life of the packaged products decreases considerably.

The object of the present invention is to solve the aforementioned problems, by proposing a container of the aforementioned type, of simpler design which makes it possible to package food products in a perfectly sealed manner, which can be easily opened without deterioration of the lid and which does not require not an additional seal.

The solution according to the present invention, to solve this technical problem, consists of a container of the type comprising a body element provided with an upper rim of non-circular shape and a cover element having a groove intended to receive at the bottom said rim of said body, and comprising a groove radially external to said groove, projecting under the latter towards the inside of said body and coming into contact with said rim of the body in the closed position of the container, characterized in that the groove has a shallower depth in the parts of small radius of curvature, such as the parts forming an angle, than in the lateral parts of the cover of greater radius of curvature, or sensiblemcnt rectilinear.

Such a container is perfectly sealed and allows food products to be kept airtight without any risk of deterioration, and can be easily opened without damaging the lid.

According to another characteristic of the invention, the depth of the abovementioned groove, in each part of small radius of curvature, is a function of the length of the arc forming said part of small radius of curvature, and in each lateral part the depth of the groove is a function of the length of said lateral part.

Another object of the present invention is to produce a vacuum packaging of products, in particular food products, which is not deformed by putting under vacuum or under neutral gas. Indeed, when using a thermoformed tray in a flexible material, it is crushed by the vacuum. This results in poor presentation and the impossibility of stacking the trays once filled one above the other. Thus, according to a particularly advantageous characteristic, the lid of a container according to the invention comprises a deformable, preformed part, capable of being deformed, during vacuuming, to conform to the profile of the food contained in the container. . This results in a neat and attractive presentation for consumers, the sealing of the tray also ensuring long-term preservation of food. In addition, such trays once filled can be easily stacked which saves space advantageously during storage.

• La figure 1 est une vue de dessus d'un couvercle conforme à l'invention ;
• La figure 2 est une vue d'un récipient, pourvu de son couvercle suivant la direction II-II de la figure 1 ;
• La figure 3 est une vue de détail de la figure 2, au niveau d'un rebord supérieur illustrant la façon dont est obtenue l'étanchéité du récipient ;
• La figure 4 est une vue en coupe suivant la ligne IV-IV de la figure 3, montrant plus particulièrement la gorge du couvercle conforme à l'invention ;
• La figure 5 représente un corps de récipient rempli de produits alimentaires ;
• La figure 6 est une vue semblable à la figure 5 représentant le corps de boîte rempli, muni d'un couvercle déformable, à l'état non déformé, selon un mode particulier de réalisation de l'invention ; et
• La figure 7 est une vue semblable aux figures 5 et 6 d'un récipient fermé montrant la partie déformable du couvercle épousant le profil des produits alimentaires contenus dans le corps de récipient, après mise sous vide.

The invention will be better understood, and other aims, characteristics and details thereof will appear more clearly on reading the explanatory description which follows, made with reference to the appended schematic drawings given solely by way of nonlimiting example illustrating several presently preferred embodiments of the invention, and wherein :

• Figure 1 is a top view of a cover according to the invention;
• Figure 2 is a view of a container, with its cover in the direction II-II of Figure 1;
• Figure 3 is a detail view of Figure 2, at an upper edge illustrating how the sealing of the container is obtained;
• Figure 4 is a sectional view along line IV-IV of Figure 3, showing more particularly the groove of the cover according to the invention;
• Figure 5 shows a container body filled with food products;
• Figure 6 is a view similar to Figure 5 showing the filled box body, provided with a deformable cover, in the non-deformed state, according to a particular embodiment of the invention; and
• Figure 7 is a view similar to Figures 5 and 6 of a closed container showing the deformable portion of the cover conforming to the profile of the food products contained in the container body, after vacuum.

In these figures, a tray of substantially parallelepiped shape is shown with a substantially rectangular longitudinal section made of polypropylene. However, it will be understood that the general principle of the invention is applicable regardless of the shape of the tray, provided that its upper edge is not circular, and whatever the material from which this tray is made. In particular, it is possible to use any plastic material such as polystyrene, polyvinyl chloride, etc., as well as any suitable multilayer material.

The tray which has been produced and which will be described here is made of polypropylene, and can withstand temperatures of the order of 120 to 130 ° C. without damage. Thus, the food products contained in such trays can be quickly cooked or reheated for example in a microwave oven, and can be eaten immediately after cooking.

Referring to Figure 2, a tray 1 according to the invention comprises a body 2 provided with an upper rim 3 of non-circular shape and a cover 4 having on its internal surface a groove 5 of cross section substantially U-shaped intended to receive at its bottom the rim 3, also of substantially U-shaped cross section.

This rim is connected to the trunk 11 of the body 2 by an angular part 12 intended to come into contact with the bottom of the cover 4 when the container is closed, thus forming a sealing point.

The cover 4 includes a groove or groove peripheral 6 radially external to the groove 5 projecting under the latter towards the inside of the container body 2. The groove 6 comes into contact with the rim 3, at the end 9 of the latter, in the closed position of the container. More specifically, the groove 6 comes to bear under the end 9 of the rim 3.

It is at this level that the perfect seal of the tray is made.

As shown in FIG. 4, the groove 6 has a smaller depth in the parts of small radius of curvature, such as the parts forming an angle A, than in the lateral parts L of the cover, of greater radius of curvature or substantially rectilinear . The invention is in fact based on the discovery that differences in the depth of the groove between the corners and the rest of the periphery of the groove 6 ensure both perfect sealing and the possibility of easily removing the cover without damaging the latter. .

The depth of the groove 6 in each part forming an angle A is chosen as a function of the length of the arc forming said part at an angle A. Thus, the depth of the groove is all the more important as the length of the arc trained is important. In general, this depth h is on the order of 0.3 to 0.8 mm, and preferably 0.3 to 0.4 mm in the example shown, where the length of the arc A is approximately 35 to 40 mm.

Similarly, in each lateral part L, the depth of the groove is a function of the length of said side portion. In general, this depth can be of the order of 0.8 to 1.1 mm and in the example shown the depth of the groove in the side parts of greater length (about 150 mm) is 1 , 1 mm while it is about 0.8 mm in the shorter side parts (about 70 mm).

Between each part of small radius of curvature and the part of greatest radius of curvature adjacent is a connecting portion of the groove R which has a concave profile followed by a convex profile.

Advantageously, the length of each connection portion R is chosen, in particular as a function of the length of the arc formed by the part of associated small radius of curvature A. Thus, the greater the depth of the groove in a connection portion, the greater the length of the arc formed by the associated angled part A. In the example shown, for a length of the part of small radius of curvature A of approximately 35 to 40 mm, each connection part extends over a length of approximately 12 to 15 mm.

As shown in particular in Figure 3, the cover 4 comprises a peripheral end edge 10 plane and substantially horizontal facilitating the gripping of the cover therefore the opening of the closed container.

FIGS. 5 to 7 show a particular embodiment of the invention which finds particular application in the packaging of products packed under deep vacuum. The cover comprises a deformable part 8 preformed, capable to be deformed during the evacuation, to match the profile of the food P contained in the container. The deformable part 8 is a convex wall of convex shape in the non-deformed state which can be easily obtained by molding.

The tray obtained after filling and evacuating (Figure 7) has various advantages. In particular, in addition to a good presentation of the finished product, these full trays can be easily stacked, hence an appreciable saving of space during storage.

Claims (10)

1. Container for food use in particular such as a tray, of the type comprising a body element provided with an upper edge of non-circular shape and a cover element having a groove intended to receive at its bottom said edge of said body, and comprising a groove radially external to said groove, projecting under the latter towards the inside of said body and coming into contact with said edge of the body in the closed position of the container, characterized in that said groove (6) has a depth more weak in the parts of small radius of curvature, such as the parts forming an angle (A), than in the lateral parts (L) of the cover of greatest radius of curvature, or substantially rectilinear. 2. Container according to claim 1, characterized in that in each part of small radius of curvature (A), the depth of the aforementioned groove (6) is a function of the length of the arc forming said part of small radius of curvature , and in that in each lateral part (L) the depth of the groove is a function of the length of said lateral part. 3. Container according to claim 1 or 2, characterized in that the depth of the aforementioned groove (6) is of the order of 0.3 to 0.8 mm for an arc length of approximately 35 to 40 mm . 4. Container according to one of claims 1 to 3, characterized in that each connecting portion of the groove, between a part of greater radius of curvature and the part of adjacent small radius of curvature has a concave profile followed by a convex profile. 5. Container according to claim 4, characterized in that the length of each aforementioned connection portion is chosen in particular as a function of the length of the arc formed by the part of small radius of curvature. 6. Container according to claim 5, characterized in that each said connection part has a length of about 12 to 15 mm, for a length of the part of said small radius of curvature of about 35 to 40 mm. 7. Container according to one of claims 1 to 6, wherein the above-mentioned upper rim (3) is of substantially rectangular shape, characterized in that the depth of the aforementioned groove (6) is 0.8 to 1.1 mm on the side parts (L) of the cover and from 0.3 to 0.4 mm in the parts of small radius of curvature forming an angle (A). 8. Container according to one of claims 1 to 7, characterized in that it is made of a thermoplastic material, such as in particular polypropylene. 9. Container according to one of claims 1 to 8, intended in particular for the sealed packaging of food products, characterized in that the above-mentioned cover element (4) has a deformable part (8) preformed, capable of being deformed under the effect of vacuum, to match the profile of the food contained in said container. 10. Container according to claim 8, characterized in that the above-mentioned deformable part (8) of the cover is a convex wall of convex shape in the non-deformed state.

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