FR2624104A1 - Cooking Tray - Google Patents

Abstract

Cooking tray made of plastic material comprising a body covered by a detachable cover supported on a collar. According to the invention, the collar 3 is covered with a thermal protection layer 6, 7, 8, a pre-cut line 4 being formed in order to detach the central section of the cover 2 and leave a protective ring on the collar. Applications: Cooking at a temperature higher than the melting temperature of the plastic material.

Description

COOKING TRAY
The present invention relates to a plastic cooking tray, intended for reheating the food contained in the tray, or for their cooking, and optionally for the formation of a gratin.

The development and improvement of the characteristics of plastic materials have made it possible to envisage new applications of these, especially at relatively high temperatures.

Plastic trays have in this case, compared to metal trays, the advantage of allowing heating or cooking by water bath, microwave oven or household oven by convection of heat emitted by resistors.

A material such as crystallized polyethylene (CPET) resists an ambient temperature in convection of around 2700 C.

The problem with this type of trays is that they must undergo, after filling the tray, and possibly a first stage of food processing, a sterilization operation, the contents of the closed tray being subjected to a temperature of the order from 1300C. At this time, an overpressure may occur inside the container, and it is for this reason that it is necessary to close the container hermetically, so that its contents are not altered until final cooking. It is also known to close such a tray with a seal whose edges are sealed at the top of the tray and, in the case where there is a flange, on and around said flange.

For the actual cooking of food, or the final stage of cooking to brown the crust or the upper part of food -which, in household ovens, is performed using a "grill" position ", the temperature becomes higher than 2700C if using forced convection or a grill. I1 follows that, in the case where the tray has an upper flange, it can melt and in general, the parts which are not in contact with the content may be altered or degraded. The object of the invention is to overcome this drawback.

According to the present invention, the plastic cooking tray comprising a body, the upper part of which forms a collar, the container being closed by a cover, detachable during the final preparation, is characterized in that the collar comprises protective means against heat.

Thus, it is possible to use temperatures higher than the melting temperature of the material constituting the tray. Such a tray therefore makes it possible to carry out cooking in a household oven without degrading the container.

Other characteristics and advantages of the invention will appear during the description which follows of particular embodiments, given only by way of nonlimiting examples, with reference to the drawings which represent - FIG. 1, a tray produced according to a first mode of
embodiment of the invention - Figure 2, a vertical sectional view. partial of a
tray according to Figure i - Figure 3, a view of a seal before its establishment
on the container - Figure 4, a view of the seal placed on the
container - Figures 5 and 6, a tray according to the invention in a
second embodiment - Figures 7 and 8, a perspective view, respectively
and in section, of a tray according to a third mode of
production.

 Surira figure 1, the container comprises a hollow body 1, of generally parallelepiped shape, advantageously made of a material such as crystallized polyethylene terephthalate, closed by a seal 2 sealed on a horizontal flange 3. The seal Z has a line of pre -incision 4 and a tear-off tab or ring 5. The structure of the protection of the flange appears better in FIG. 2. The cover 2 is constituted by a first layer of aluminum 6, by an insulating layer for example in cardboard 7, and by a second outer layer 8. The outer layer 8 is, according to a characteristic of the invention, a reflective layer for example of aluminum, which has the power to reflect a large fraction of the infrared rays emitted by the grill. In addition to this reflection, the insulating layer 7 prevents the transmission of the heat induced in the ring 8 to the collar 3. Thus, the collar 3 remains at a temperature much lower than that which it would reach if it was directly in front of the heat source. The layer 7 being relatively thick, is more rigid than the sheets 6 and 8, and perfectly defines the part to be torn off. Preferably, the pre-incision line 4 cuts only the layers 7 and 8 of the cover, the lower layer 6 remaining intact but being torn during opening, by adhesion to the rigid layer 7, along the edges pre -incised with this layer. Indeed, in the case of cooking the cover must be opened so that the heat effectively reaches the food. The opening can thus be carried out without tools or cutting. We schematized by the reference P the product contained in the tray.

FIG. 3 represents, in perspective, a cover of the type which can be used to close a container such as that which is represented in FIG. 1. It naturally includes the pre-incision lines 4 and the pull-out tongue or ring 5. Furthermore, in addition to the upper surface, the cover has four sides 9 which can be folded over the edges of the collar, and it is thus possible to obtain a complete package with a decoration and a definitive presentation.

Of course, between the different layers constituting the cover, are arranged layers of adhesive (not shown), the cover itself being sealed by thermocompression, high frequency induction or ultrasound.

As shown in FIG. 4, the sides 9 of the cover 2 are folded down, then welded or glued at their junction points with the flange or on the walls of the container 1. They can also be simply folded perpendicularly to the flange for give the whole an exactly parallelepiped shape. They can also be placed under a heat-resistant plastic film, for example made of polyetherimide, giving the assembly mechanical homogeneity. The decoration can be pre-printed on the sides and the top of the cover.

Figures 5 and 6 show a second embodiment in which, on the cover 2, there is an insulating ring 10 which covers the part to be protected and remains in position, after tearing off the cover along the inner contour of the insulating ring 10. This rim 11 protects against the infrared radiation, substantially perpendicular to the collar, the upper part of the container which is not in contact with the products to be heated. On the other hand, the products absorb heat as long as they have not been calcined, so that they protect their packaging for the parts which are not in contact. Advantageously, the ring 10 projects slightly inside the container (reference 11) to allow better protection of the collar 3.

Figures 7 and 8 show a third embodiment, the previous references having been preserved.

In this embodiment, the cover is constituted for example by an aluminum foil or a metallized film, and it has, as before, a pre-incision line 4 making it possible to tear off the cover without a cutting tool. As in the previous embodiment, the annular part of the cover remains in place and glued to the flange 3, overflowing with a thickness 11 of a millimeter for example, on the interior of the container 1. At the tearing off the cover, for cooking, there remains on the collar 3, a reflective layer which allows its protection 3.

As in the first embodiment, a layer of adhesive (not shown) is placed between the collar 3 and the protective layer 8 or 10.

It goes without saying that many variants can be introduced, in particular by substitution of technically equivalent means without departing from the scope of the invention.

Claims (6)

1. Plastic cooking tray comprising a  body whose upper part has a collar, the  flange being covered by a detachable cover,  characterized in that the collar (3) has  means of protection (6, 7, 8, 10) against heat. 2. Tray according to claim 1, characterized in that  the cover has a pre-incision line (4) leaving  remain on the collar (3) at least one layer of  reflective or insulating protection. 3. Tray according to claim 1, characterized in that  the cover is a multilayer complex, comprising at  at least one reflective top layer (8) and at least  an insulating layer (7). 4. Tray according to one of claims 1 or 2,  characterized in that the protective layer (10) is a  insulating layer placed above the collar (3). 5. Tray according to one of claims 1 or 2,  characterized in that the protective layer is a  reflective layer (8). 6. Tray according to one of claims 4 or 5,  characterized in that the width of the protection (8, 10)  is greater than the width of the collar (3) so  to project (11) inside the container (1).