NL2010144C2 - PACKAGING AND METHOD FOR MANUFACTURING A PACKAGING - Google Patents

Description

Title: Packaging and method for manufacturing a package

The invention relates to a package comprising a whole of a receptacle with an open side and an annular lid edge which is located on the open side of the receptacle on an outer peripheral edge of the receptacle, and which by means of a relatively weak break-through section with the is connected. The invention also relates to a method for manufacturing such a package.

The invention furthermore relates to a package comprising a whole of a receptacle with an open side and an annular lid rim surrounding the receptacle, on the open side of the receptacle, and which is connected to the receptacle by means of a snap connection.

The packages as described above are generally made from plastic.

An example of the method for manufacturing a package with a whole of tray, break-through part and lid edge is shown in FR 2 618 411. To close the tray from the package, a piece of cover film is provided according to the known method, which at least at the lid edge of the package, and possibly also at the tray. Upon first use of the package, a user breaks through the breakthrough portion between the lid edge and the tray, and then pulls the whole of the lid edge and cover foil away from the tray, thereby breaking any connection between the cover foil and the tray. From that first use, the whole of lid edge and cover foil, which will hereinafter be referred to as lid, can be placed back on the tray or removed from it as desired. Near the open side, the receptacle has a recess into which a portion of lid edge can snap, so that a temporary connection between the lid and the receptacle can always be established on that basis. The tray and the lid rim are manufactured as a whole by means of injection molding, wherein the breakthrough part is on the one hand thick enough to be able to have a plastic flow through this part during the injection molding process, and on the other hand it is thin enough to make it possible for a user of the package make the lid edge come loose when the container is first used.

2

An important advantage of the known method is that the inner space of the container can remain completely closed off from the outside world until the first use. The connection between the cover foil and at least the lid edge can be realized over the entire circumference of the lid edge, so that there is nowhere an interruption in the connection that could be a leak between the inner space of the tray and the outside world. Another important advantage is that material is saved by making the cover film, which is used in the first instance to completely seal the inner space of the container, an integral part of the lid. This is different from many conventional situations in which a piece of cover foil is first connected to a tray, after which a complete lid is placed on the sealed tray, over the cover foil, usually by means of a snap connection. In such situations, a user firstly removes the lid from the tray, then peels off the cover foil from the tray, and throws it away, or possibly leaves it partially pulled away from the tray. In any case, the cover film then no longer has a sealing function. After first use, it is only the lid that actually performs this function.

It is particularly important when packaging foodstuffs that a container for first use is reliably sealed. There is then practically no risk that the container may open unintentionally and that the contents of the container may be lost.

For certain types of food, it may be important to have an airtight seal, because it can then guarantee a certain shelf life of the packaged food.

WO 2005/039997 relates to a method for manufacturing a package with a tray and a lid that comprises a lid edge and a piece of cover film, wherein the tray and the lid edge are formed separately from each other and then brought together, or wherein the tray and the lid rim are connected to each other via one or more pieces of material, which then serve as hinges. In both cases, the lid edge must first be placed correctly on the tray before the cover film is applied.

DE 93 11 330 shows a package with a whole of receptacle, breakthrough section and lid edge, wherein the open side of the receptacle is closed by means of a piece of cover foil connected to the lid edge, and wherein the breakthrough section and the lid edge are the outer peripheral edge of surrounded the container. Prior to the first use, a surface of the lid edge to which the cover foil is connected is located at a higher level than the outer peripheral edge of the tray. Once the breakthrough portion has been breached, the whole of the lid edge and cover foil can be replaced as a lid on the tray, with an inwardly projecting portion of the lid edge engaging the outer peripheral edge of the tray.

A drawback of the method known from FR 2 618 411 is that the design of the package results in that it is practically only possible to produce the whole of tray, break-through part and lid edge by means of injection molding.

The same applies in connection with the manufacturability of the packaging that is known from DE 93 11 10 330. A disadvantage of the method known from WO 2005/039997 is that an additional step of placing the lid edge on the tray must be carried out before the cover foil can be applied to the assembly of tray and lid edges.

It is an object of the invention to provide a method for manufacturing a package with a tray, a break-through portion and a lid edge, wherein the making process can be efficient and relatively inexpensive, which is desirable since the package is typically a product that is suitable for mass production, and wherein it is also possible to provide a reliable closure of the tray prior to a first use, in particular a closure by means of a piece of cover film around the aforementioned advantages of saving material and avoiding the use of cover film that no longer has any function after first use.

The stated object is achieved by a method for manufacturing a package comprising a whole of a container with an open side and an annular lid edge which is located on the open side of the container on an outer peripheral edge of the container, and which is of a relatively weak break-through portion is connected to the tray, wherein a mold having an inner surface formed towards a lower surface of the package is provided, wherein a sheet is provided and placed in the mold, a movement of the sheet is forced to bring the sheet into a state in which it is at least against the inner surface of the mold and is thereby an intermediate shape of the package, with the tray and the lid edge of the package, and wherein material of a portion of the intermediate shape is located at the location of a transition from the tray to the lid edge, is removed in order to break through the break-away portion of the package to realise.

For the sake of completeness, it is noted that the terms "above" and "defect" as used in connection with the package according to the invention must be understood as being related to a normal orientation of the package, i.e., a orientation in which the open side of the receptacle is at the top. The terms "inside" and "outside" are related to a central axis (symmetry axis) of the annular lid edge.

According to the invention, the whole of tray, breakthrough part and lid edge is manufactured on the basis of a sheet that is brought into a mold in the desired shape, the breakthrough part being obtained by removing material at the position where this part is to be present. . In a practical elaboration of the invention, the sheet is initially flat. The sheet is then subjected to forces in the mold to bring it into the desired shape defined in the mold. This can be done, for example, by applying techniques known as vacuum forming or thermoforming. In general, with these techniques known per se, material is first heated and then plastically deformed. The techniques are eminently suitable for the production of shaped products in mass production of flat sheets, which can also be classified as films or sheets, for example. An additional step according to the invention is the removal of material at the location of a transition from the tray to the lid edge so as to realize the break-through portion.

Vacuum forming or thermoforming is a relatively inexpensive manufacturing method, assuming that the mass production method is used. Furthermore, vacuum forming or thermoforming offers the possibility to use various types of plastic, including PVC (polyvinyl chloride), PET (polyethylene terephthalate) and APET (amorphous polyethylene terephthalate). The latter material is extremely suitable for use in food packaging, since it has good barrier properties, that is, it is capable of exchanging gas between a sealed interior of a package and an environment of the packaging. As a result, it is able to prevent oxygen from the air from getting into a package too quickly, which benefits the shelf life of foodstuffs packed in a protective atmosphere.

5

It is particularly advantageous if the part of the intermediate form of the package which is intended to form the break-through part, that is to say the part of the intermediate form which is situated at the location of the transition from the tray to the lid edge, as a curved part with a concave shape on the lower surface of the intermediate mold, that is, the surface of the intermediate mold facing the inner surface of the mold, and a concave shape on an upper surface of the intermediate mold. On the basis of the curved shape, the intermediate shape of the package clearly defines the place where the break-through part is to be realized, namely in the valley of this shape. For removing material, any suitable tool is used that can easily find the correct position within the curved shape. Because the curved shape is concave at the top, the step of removing material can be carried out while the intermediate shape is still in the mold.

Within the scope of the invention it is possible to carry out the step of removing material that is in the intermediate form at the location of a transition from the tray to the lid edge, simultaneously with a step of detaching the package from surrounding sheet material. The packaging is then, as it were, further completed after the forming process in a single punching movement. Incidentally, the removal of material can be carried out by any suitable machining technique or any suitable cutting technique. Of the latter technique, punching is an example, and gradually loosening another example. It is favorable when the packaging of the packaging takes as little time as possible. Simultaneously performing the steps mentioned can contribute to this.

This does not alter the fact that it is also possible within the scope of the invention to perform these steps in succession.

The removal of material can be carried out in such a way that the portion of the intermediate shape of the package intended to form the break-through portion is made thinner relative to the tray and the lid edge. Because the portion is made thinner, it is achieved that a wall thickness of the resulting breakthrough portion is significantly smaller than a wall thickness of the tray and the lid edge, whereby it is even possible to break through the breakthrough portion with manual force. Instead of making the intended part thinner or in addition to making the intended part thinner, openings can be realized at defined places between the tray and the lid edge 6. The breakthrough portion is then perforated, whereby breaking through this portion is easier than if it were relatively thin, but uninterrupted. With only a thinner breakthrough portion, it is possible to use the package to package contents in an airtight manner, while with a perforated breakthrough portion that usually will not be intended.

In a practical application of the method according to the invention, the sheet is heated before it is moved towards the inner surface of the mold. In general, it can be assumed that the material of the sheet is more easily deformable in the heated state than in the unheated state. This is in any case the case with many common types of plastic.

A desired movement of the sheet against the inner surface of the mold can be realized by applying a pressure difference over the sheet. For example, an underpressure can be created on one side of the sheet that faces the inner surface of the mold.

The package obtained by applying the method of the invention can be provided in a simple manner with a piece of cover foil to close the package. Such a piece of cover foil is then in any case connected to the cover edge. This can be done in a situation in which the lid edge and the receptacle are connected to each other via the break-through part, but it is also possible to do this after the break-through part has first been broken. The lid edge and the container are then detached from each other by forcing a limited mutual movement of the lid edge and the container, thereby breaking through the break-through portion. This can then be done mechanically, while in the first case the breaking through of the break-through part will usually be carried out manually by a user of the package. With regard to the first case, it is further noted that a package can be obtained in which the cover film is at a higher level relative to a bottom of the tray prior to the first use than once the break-through portion has been broken. In particular, this is possible when at least a portion of the lid edge protrudes upwards relative to the tray 30, from the break-through portion when it has not yet been broken, in the normal orientation of the package in which the open side of the tray is located. as stated earlier, and in which the bottom of the tray is at the bottom. As soon as the breakthrough portion has been broken, the whole of the lid edge and piece of cover film, which forms a lid for the tray, is replaced at a lower level on the tray when it is intended to close the open side of the tray, there is an overlap between the receptacle and the lid rim in height direction in order to be able to engage the lid rim on the receptacle. The lower level of the lid after the first use does not present a problem when it is assumed that with the first use the content of the package is reduced because a portion of the content has been removed for consumption. This is in particular the case when the packaging is used for packaging foodstuffs, for example for packaging mushrooms, grapes or strawberries.

In the situation in which the break-through portion is broken during the manufacturing process, the connection of the piece of cover foil to at least the cover edge can be done simultaneously with the release of the cover edge from the tray, but possibly also only once the cover edge and the tray have been removed. have been detached from each other and the mutual movement has ended, or just before that.

When the cover foil is connected to the lid edge before the lid edge is completely detached from the tray, it is prevented that a situation could arise in which the cover edge moves spontaneously with respect to the tray, for example under the influence of gravity, and with it a adopts an undesired position relative to the container.

The mutual movement of the lid edge and the container aimed at releasing the lid edge from the container, whereby the break-through portion is broken, can be terminated when a surface of the lid edge and a peripheral surface of the container adhering to the open side of the tray, are at a substantially equal level. When the receptacle is considered in the aforementioned normal orientation, in which the open side of the receptacle and the lid edge can be said to be at an upper side, then an annular surface on the upper side becomes with the peripheral surface of the receptacle of the container. It is practical when the shape of the package is chosen to have concentric upper surfaces of the lid edge and the tray, so that it is possible to bring these upper surfaces to a substantially equal level in order to provide a usable support surface for a portion of the piece of cover film. the circumference of the piece. In that situation the desired connection between the cover foil and at least the cover edge can then be realized. This does not alter the fact that it is also possible to establish the aforementioned desired connection earlier, as has already been described above.

In the case of a break-through portion that has already been broken through, it is desirable to have a fixed connection between the tray, the lid edge and the piece of cover foil for first use, in order to prevent the lid, that is, the combination of the lid edge and if the piece of cover film can unintentionally come off the tray and ensure a proper closure of the inner space of the tray from the outside world, it is possible that the piece of cover foil can be connected to both the tray and the lid edge. A stronger connection can then be realized between the piece of cover foil and the lid edge than between the piece of cover foil and the tray, so that the piece of cover foil comes off automatically from the tray and not from the cover edge when a user detaches the foil during first use. When an uninterrupted connection over the entire circumference of the tray, on the open side of the tray, and over the entire lid edge is realized, then a double closure of the interior space of the tray is obtained, which provides extra security when it comes to to protect a possible contents of the container against external influences.

The limited mutual movement of the lid edge and the container, which is forced for the purpose of releasing the lid edge and the container from each other, can be a linear movement. Such a movement is easy to perform. In a practical case, for example, it may be that the lid edge is only moved down a little bit relative to the tray. Furthermore, it is a practical possibility that the mutual movement of the lid rim and the tray is terminated with the establishment of a snap connection between the lid rim 25 and the tray. A making process of the package according to the invention in which the snap connection is already established then comprises the following steps: forming the package as a whole of tray, lid edge and break-through portion, forcing a mutual movement of the tray and the lid edge until these click on each other, breaking through the break-through part, and providing the piece of cover film and fixing the cover film on at least the cover edge.

On the basis of the aforementioned possibility of having a curved shape of the sheet at the area of the break-through portion, it is not necessary for the lid edge and the tray to be formed with components which are adapted to move the lid edge and the tray when the lid is moved relative to one another to establish a click connection between the 9 lid edge and the receptacle. In fact, as soon as the breakthrough portion is broken, the portions of the lid rim and the receptacle that were previously connected to each other, due to tension that has been present in the package up to that point, are slightly extended in a direction towards each other, that is, at the lid edge inwards, and at the tray outwards. The click connection can be established based on this data. The lid edge can be moved over the tray as long as said sections that were previously connected to each other slide over each other, and are connected to each other as soon as the sections come into a mutual position in which they can spring out relative to each other. When the packaging is made of plastic, the flexibility required for this is sufficiently available.

In general, the components of the tray and the lid rim that play a role in establishing a snap connection within the scope of the invention can have any possible suitable shape. The diameter of at least a part of an inner circumferential surface of the lid edge can be adjusted to the outer diameter of an upper part of the tray such that in any case the lid edge is forced to collapse slightly when the lid edge is moved along the tray. The snap connection is hereby realized, which can easily be broken by a user by grasping a part of the lid edge, tilting this part slightly away from the tray and then pulling the entire lid edge away from the tray.

For establishing the connection between the piece of cover foil and at least the cover edge, any suitable technique for allowing two components to adhere to each other can be used. Local heat supply can thus be provided, so that the components melt together at the relevant location.

It may be advantageous to use means to support at least the lid edge during the connection between the piece of cover film and at least the lid edge.

The packaging produced with the method according to the invention can be used for packaging for various materials. As noted earlier, the packaging of food is certainly possible.

In general, the material to be packaged is placed in the tray before the piece of cover film is connected to at least the lid edge.

10

The invention also relates to a package that can be manufactured using the method described above. According to a first aspect of the invention, it is then a package comprising a whole of a container with an open side and an annular lid edge which is located on the open side of the container on an outer peripheral edge of the container, and which is of a relatively weak break-through part is connected to the tray, which is entirely formed on the basis of a sheet, wherein material is removed from the sheet at the break-through part, and where the sheet is curved at the break-through part, with a convex shape on a lower surface of the package, and a concave shape on an upper surface of the package. At the location of the break-through part, the sheet can be made thinner relative to the tray and the lid edge. Thereby or instead the breakthrough portion may be provided with openings. The package can further be made complete with a piece of cover foil which is connected to the lid edge and closes the tray, wherein in practice material is present in the tray.

According to a second aspect of the invention, a package is provided which comprises a whole of a receptacle with an open side and an annular lid rim surrounding the receptacle, on the open side of the receptacle, and which is connected to the receptacle by means of a snap connection. is formed entirely on the basis of a sheet, wherein the lid edge and the container are broken away from each other, an inner peripheral edge of the lid edge being partially curved, and wherein an outer peripheral edge of the container is also partially curved. The specific shapes of the peripheral edges as mentioned are then based on the curved shape that may be present at the location of the break-through portion in the package, before the break-through portion has been broken, as previously described.

The package as defined above can further be completed with a piece of cover foil which is at least connected to the lid edge and closes the tray, wherein in practice material is present in the tray. A plane of the lid edge and a peripheral surface of the tray that is located on the open side of the tray 30 can be at a practically equal level. This is particularly favorable with regard to an embodiment of the package in which the piece of cover foil is connected to both the tray and the lid edge, wherein the piece of cover foil can lie flat on the package. As noted earlier, in the case of a double connection of the cover foil, it is advantageous if a connection between the piece of cover foil and the lid edge is stronger than a connection between the piece of cover foil and the tray, so that it can be guaranteed that the cover remains intact when the packaging is opened for the first time.

The invention will be further elucidated on the basis of the following description of a method for manufacturing a package, wherein a sheet in a mold is made into a whole of a tray and a lid edge with a relatively weak break-through part in between, in particular by deforming the sheet and removing material from the sheet, and wherein the tray is closed using a piece of cover film, possibly not before the break-through portion is first broken. Reference will be made herein to the drawing, in which like reference numerals indicate like or comparable parts, and in which: figure 1 shows a package according to the invention schematically and in cross-section; Figure 2 schematically shows a top view of the package; Figure 3 shows schematically and in cross-section a detail of the package; Fig. 4 schematically shows a part of a break-through part between a tray and a lid edge of the package; Figure 5 shows schematically and in cross-section a part of a mold and a part of a sheet which is formed into the package using the mold, with the sheet in a flat condition; Figure 6 shows schematically and in cross-section a part of the mold and a part of the sheet, with the sheet in deformed state; Figure 7 illustrates how a piece of cover film is connected to the lid edge of the package, wherein an edge portion of the tray and the lid edge are supported; Figure 8 shows the same detail of the package as Figure 3 for a state of the package in which the break-through portion has been broken and a releasable connection between the tray and the lid edge has been established; and Figure 9 illustrates how a piece of cover film is connected to both the tray and the lid edge in the condition of the package as shown in Figure 8, supporting an edge portion of the tray and the lid edge.

12

Figures 1 and 2 show a package 1 according to the invention, which in a preferred embodiment is entirely made of plastic, and which comprises a whole of a container 10, a lid edge 20 and a relatively thin break-through portion 30 between the container 10 and the lid edge 20. In the example shown, the tray 10 has a bottom 11 and an upright wall 12 which extends from the bottom 11 and which has a substantially round circumference. Any shape of the tray 10 is possible within the scope of the invention, the tray 10 having at least one open side 13. In the following description, a normal orientation of the tray 10 will be assumed, that is, an orientation in which the bottom 11 of the tray 10 is at the bottom, and wherein the open side 13 is at the top. At the open side 13, the container 10 is provided over the entire circumference with a specially designed edge portion 14 with an upper surface 15, which is a peripheral surface of the container 10, as can clearly be seen in the detail of the package 1 shown in Figure 3 The function of the edge portion 14 will be explained below.

The lid edge 20 is annular and completely surrounds the tray 10 at the open side 13, the lid edge 20 being firmly connected to the tray 10, on an outer peripheral edge 16 of the tray 10. The peripheral shape of the lid edge 20 is aligned with the peripheral shape of the tray 10. The annular shape of the lid edge 20 can therefore be round, but also, for example, rectangular or square, depending on the circumferential shape of the tray 10.

The break-through portion 30 is located between the lid edge 20 and the tray 10. Figure 4 illustrates the fact that the break-through portion 30 can be perforated, so that although there is a mutual connection between the tray 10 over the entire circumference of the tray 10 and the lid edge 20. and the lid edge is 20, but there are also interruptions 31 at defined places. As a result, an action of breaking through the break-through section 30, as will be described below, requires less force than if the break-through section 30 were to be uninterrupted.

The lid edge 20 has an inner protrusion 21 and an outer protrusion 22. The functions of these protrusions 21, 22 will be explained below. Viewed in the normal orientation of the whole 1 of the tray 10 and the lid edge 20, the protrusions 21, 22 of the lid edge 20 extend substantially in the vertical, downward direction.

13

A manufacturing process of the package 1 is explained with reference to Figures 5 and 6. In the example shown, a flat plastic sheet 40 forms the basis of the package 1. A part of this sheet 40 is shown in figures 5 and 6. Furthermore, in the said figures a part of a mold 41 can be seen which is applied 5 for the manufacturing process in which the sheet 40 is deformed.

An inner surface 42 of the mold 41 has a shape that is precisely matched to the desired shape of the package 1, in particular the desired shape of a lower surface 17 of a whole of the tray 10 and the lid edge 20. For the purpose of deforming of the sheet 40, the sheet is placed in the mold 41 and heated. Subsequently, an underpressure is created on one side of the sheet 40 which faces the inner surface 42 of the mold 41, so that the sheet 40 is sucked towards and comes to lie against the inner surface 42. The condition of the sheet 40 thus obtained is shown in Figure 6. It is noted that the process with which the sheet 40 is deformed is known as vacuum forming or thermoforming. In a manner known per se for the purpose of creating said underpressure, the mold 41 can be provided with openings (not shown) at suitable positions through which air can be extracted from the space between the sheet 40 and the inner surface 42 of the mold 41 .

Once the sheet 40 has been deformed in the manner described above, an intermediate form 2 of the package 1 has been obtained in which the tray 10 and the lid edge 20 connect directly to each other and no weakening has yet been realized in the sheet 40 around the breakthrough portion to obtain. In the intermediate mold 2 there is also a piece 43 of the sheet 40 which surrounds the lid edge 20. In order to move from the intermediate mold 2 to the final package 1, at least two further actions must therefore be carried out, after the step of deforming the sheet 40. These actions involve the removal of material at a position where the tray 10 and connecting the lid edge 20 to each other and releasing the package 1 from the surrounding piece 43 of the sheet 40. The actions can be carried out in the mold 40, the actions being carried out simultaneously for a very efficient manufacturing process of the package 1 to be realized. The actions can be realized by means of a punching process, wherein punching tools (not shown) are applied and movements are made through the intermediate mold 2 at the appropriate positions, so that cuts are made at the appropriate positions. On the basis of the material being cut away from a part 3 which is situated at the location of the transition 14 between the tray 10 and the lid edge 20, the relatively weak breakthrough part 30 is then formed, optionally with interruptions / openings 31 as previously based on Figure 4 is described. The realization of the breakthrough portion 30 can for instance also be regarded as pre-grooving of the connection of the lid edge 20 to the tray 10. Removing material can also involve moving material. Furthermore, the intermediate shape 2 of the surrounding piece 43 is cut off from the sheet 40. At that moment the package 1 is ready.

The shape of the inner surface 42 of the mold 41 is aimed at providing the sheet 40 with a strong curvature at the area 3 of the intermediate mold 2 intended to be formed into the break-through portion 30 of the package 1 whereby the portion 3 acquires a substantially U-shaped appearance. In particular, the U-shape is oriented upright, that is, at the location of the curvature, the lower surface 17 of the intermediate mold 2 is convex and an upper surface 18 of the intermediate mold 2 is concave. The said shape has the advantage that in the intermediate shape 2 the position where the break-through part 30 is to be formed by removing material is clearly defined, namely in the valley of the U-shape. It is also possible to have the punching tool or any other tool used to form the breakthrough portion 30 find itself a path within the U-shape to the correct position. These aspects of the design contribute to the accuracy and reproducibility of the manufacture of the package 1, and also enable efficient and rapid manufacture.

Once the package 1 has been formed, preferably in the manner as described above, a next production step can be carried out, which is illustrated in Figure 7. This next production step is aimed at providing and applying a piece of cover film 50 around the open side 13 of the receptacle 10, and to form a complete lid 23 together with the lid edge 20.

In the mutual position that the edge portion 14 of the tray 10 and the lid edge 20 have relative to each other when the break-through portion 30 is intact, an upper surface 24 of the lid edge 20 extends at a higher level than the upper surface 15 of the edge portion 14 of the tray 10. The top surface 24 of the lid edge 20 can thus support the piece of cover foil 50 on the circumference. If it is desired to provide the piece of cover film 50 in this situation, the piece of cover film 50 is only connected to the cover edge 20, preferably over the entire circumference of the upper surface 24 of the cover edge 20. This achieves that the tray 10 is closed, and also that the lid 23 is assembled, wherein there is a firm connection between the piece of cover foil 50 and the lid edge 20. The piece of cover film 20 is located at a higher level than the upper surface 15 of the edge portion 14 of the container 10, which is favorable for packaging foodstuffs such as mushrooms, grapes or strawberries, because then the container 10 can be filled completely to the top without the cover foil 50 pressing against the filling once it has been applied. If it is desired to have an airtight seal of the tray 10, then this is possible with a connection between the piece of cover foil 50 and the cover edge 20 over the entire circumference of the upper surface 24 of the cover edge 20, and thereby an intact break-through portion 30 that is thin, but not perforated.

A possibility for establishing the connection between the piece of cover foil 50 and the cover edge 20 is the local application of heat, so that the cover foil 50 melts onto the cover edge 20 at a defined location. This can be done in a manner known per se with the aid of appropriate tools 60, generally also referred to as knives, a part of which is schematically shown in Figure 7. It can be favorable to support the lid edge 20, and optionally also the edge portion 14 of the tray 10, during the connection process. A suitable support 61 is then used for this purpose, part of which is shown schematically in Figure 7.

The assembly of the tray 10 and the lid 23 is intended to be used for packaging material (not shown) which is placed in the tray 10 at any suitable moment prior to the application of the piece of cover film 50 . In particular, it can be foodstuffs, for example mushrooms, grapes and strawberries as mentioned earlier, and for example also salads, nuts, butter and other dairy products such as yogurt. In the case of foodstuffs, it may be important that the container 10 is completely closed prior to the first use. This can be achieved with the method described above if the breakthrough portion 30 is thin, but uninterrupted. The container 10 may optionally be sealed under a protective atmosphere or under other desired conditions.

16

In the example shown, the assembly of the tray 10 and the cover 23 is ready for first use after the piece of cover film 50 has been applied. In that first use, a user grasps the lid edge 20 at a location on the outer protrusion 22, and exerts forces on the lid edge 20 aimed at breaking the breakthrough portion 30, so that an inner peripheral edge 25 of the lid edge 20 comes off from the outer peripheral edge 16 of the tray 10, after which the lid 23 can be removed from the tray 10. After the first use, the user can reclose the tray 10 by placing the lid 23 back on the tray 10, thereby exerting slight downward pressure, whereby a snap connection between the cover 23 and the tray 10 can be established. A possible mutual position of the tray 10 and the lid edge 20 in that case is shown in Figure 8. In this position, the lid edge 20 engages the edge portion 14 of the tray 10, the inner peripheral edge 25 of the lid edge 20 not being vertical. can easily move beyond the outer peripheral edge 16 of the tray 10. Re-opening the steps of the container 10 by lifting the click connection and removing the lid 23, and closing the container 10 again by placing the lid 23 on the container 10 and establishing the click connection can be done as desired repeated, as often as desired.

A favorable aspect of the design of the package 1 is that as soon as the breakthrough portion 30 is broken, the tension that was previously present in the whole of the container 10 and lid edge 20 falls away, whereby a portion 19 of the container 10, which is connected to a free one end has the outer peripheral edge 16 of the tray 10, and the inner protrusion 21 of the lid edge 20, which has the outer peripheral edge 25 of the lid edge 20 at a free end. As a result, the aforementioned portion 19 of the tray 10 comes out slightly more, and the inner protrusion 21 of the lid edge 20 comes up slightly more. Thus, no additional design aspects are required, such as lugs, recesses, and the like, to enable a snap connection. Instead, said portion 19 of the tray 10 and the inner protrusion 21 of the lid edge 20 are automatically adapted to hook one after the other through the break-through portion 30. A snap connection is accomplished by pressing down the lid edge 20 on the tray 10, with the inner protrusion 21 of the lid edge 20 slightly invading until the inner peripheral edge 25 of the lid edge 20 moves beyond the outer peripheral edge 16 of the tray 10. To release a snap connection, a user can initially hold a portion of the lid edge 20 at the outer protrusion 22 and thereby tilt the inner protrusion 21 away from the outer peripheral edge 16 of the tray 10.

As an alternative to the method described above for applying a piece of cover foil 50 to the package 1 in order to close the tray 10, it is possible that first the lid edge 20 is brought to a lower level with respect to the tray 10, wherein the break-through portion 30 is broken so that the mutual position of the lid edge 20 and the tray 10 as shown in Fig. 8 is obtained, i.e. a mutual position in which the upper surface 15 of the edge portion 14 of the tray 10 and the upper surface 24 of the lid edge 20 are at substantially the same level. The following describes how the further process proceeds in that case.

In a first step, a downward pressure is exerted on the lid edge 20, wherein the breakthrough portion 30 is completely broken, and the lid edge 20, as a result, comes off the tray 10. As noted earlier, for this process of breaking away the lid edge 20 from the tray 10 less force is required when the break-through portion 30 is perforated. At a given moment during the downward movement of the lid edge 20, the snap connection described above is established between the lid edge 20 and the tray 10. The downward movement is stopped when the top surface 15 of the edge portion 14 of the tray 10 and the top surface 24 of the lid edge 20 are at substantially the same level. At that moment a next production step can be carried out, as illustrated in figure 9. This next production step is aimed at providing and applying a piece of cover film 50 to close the open side 13 of the tray 10, and together with the lid edge 20 to form a complete lid 23.

Because the top surface 15 of the edge portion 14 of the tray 10 and the top surface 24 of the lid edge 20 extend at a substantially equal level, these two top surfaces 15, 24 can support the piece of cover film 50 on the circumference. In the example shown, the piece of cover film 50 is connected to the package 1 at two places, namely on the top surface 15 of the edge portion 14 of the tray 10, over the entire circumference, and on the top surface 24 of the lid edge 20, also over the entire circumference. This ensures that the tray 10 is sealed airtightly, and that the cover 23 is also assembled, wherein there is a firm connection between the piece of cover foil 50 and the cover edge 20.

It is possible to connect the piece of cover film 50 to the upper surface 24 of the cover edge 20 earlier. This is even possible during the mutual movement 5 of the tray 10 and the lid edge 20 which is designed to come to the snap connection and to bring the aforementioned upper surfaces 15, 24 to a substantially equal level. Advantages are that the making process can be faster, and that the lid edge 20 cannot move beyond the desired position relative to the edge portion 14 of the tray 10. Because the connection between the piece of cover foil 50 with the tray 10 usually has to be less strong than the connection between the piece of cover foil 50 and the cover edge 20, the establishment of the latter connection usually requires more time than for establishing the first-mentioned connection. If the connection that requires more time is already at least partially realized during the mutual movement of the tray 10 and the lid edge 20, time can be saved, and the costs of the manufacturing process can therefore be lower.

In line with what has been noted previously, a possibility for establishing the connections between the piece of cover foil 50 and the tray 10 and the cover edge 20 is the local supply of heat, so that the cover foil 50 at 20 defined places on the tray 10 and melt the lid edge 20. This can be done in a manner known per se with the aid of appropriate tools 60, a part of which is shown schematically in Figure 9. It can be advantageous to support the lid edge 20, and optionally also the edge portion 14 of the tray 10, in the connection process. A suitable support 61 is then applied for this purpose, a part of which is shown schematically in Figure 9.

When applying cover foil 50 in the situation in which the break-through portion 30 has already been breached, it can be chosen to only establish a connection between the cover foil 50 and the cover edge 20. Incidentally, for both this connection and the possible connection between the cover foil 50 and the edge portion 14 of the tray 10, the connection does not necessarily have to be over the entire circumference. In view of the desire to obtain a sturdy lid 23, wherein the lid edge 20 and the piece of cover foil 50 cannot easily be pulled apart, a complete connection between the piece of cover foil 50 and the lid edge 20 is, however, preferred. In general, the places where a connection must be made can be determined as required, taking into account in particular a possible desire to completely close off the interior space of the tray 10.

In the example shown, the assembly of the tray 10 and the lid 23 is ready for first use after the desired connections have been made. In that first use, a user grasps the lid edge 20 at a location on the outer protrusion 22, breaks the snap connection between the lid edge 20 and the tray 10, and pulls the lid 23 off the tray 10, the connection between the cover foil 50 and the tray 10 is broken, while the connection between the cover foil 50 and the lid edge 20 remains intact. If during the making process of the assembly the piece of cover foil 50 is connected to both the tray 10 and the lid edge 20, then it can be chosen to make the connection with the tray 10 less strong than with the lid edge 20, as already noted earlier so that it is ensured that only the connection between the piece of cover foil 50 and the tray 10 is broken. Important advantages of the assembly of the tray 10 and the lid 23 described above and the way in which this can be manufactured are listed below.

- The assembly is suitable for packaging foodstuffs which must be packaged air-tight prior to first use, because a connection between the piece of cover foil 50 and the tray 10 can be established over the entire circumference. If the connection between the piece of cover foil 50 and the cover edge 20 is also over the entire circumference, there is even a double seal, although the seal on the cover edge 20 is somewhat less reliable, because it passes beyond a transition from the tray 10 to the lid edge 20 is positioned.

25 - Closing the tray 10 prior to the first use does not require a separate piece of cover film that no longer has a function after the first use, unlike in many conventional situations. This makes the assembly more environmentally friendly. Because the piece of cover foil 50 is integrated in the cover 23, a relatively light cover 23 is obtained, whereby material is saved.

The tray 10 and the lid edge 20 which forms part of the lid 23 can be manufactured in a relatively simple and inexpensive manner by means of thermoforming or vacuum forming, starting from a flat sheet 40 and using a mold 41. The lid edge 20 is directly in the correct position with respect to the tray 10, possibly after breaking through a relatively thin break-through portion 30 between the tray 10 and the lid edge 20. The lid 23 does not have to be manufactured separately and no additional step is required to position lid 23 on tray 10.

- The assembly is easy to handle by a user, wherein during first use the cover 23 can be pulled off in a simple manner, and wherein during further use a snap connection between the cover 23 and the tray 10 is always easily established or can be broken.

It will be clear to a person skilled in the art that the scope of the invention is not limited to the examples discussed above, but that various variations and modifications thereof are possible without departing from the scope of the invention as defined in the appended claims .

With regard to the piece of cover film 50, it is noted that it can be made from any suitable material, for example plastic or aluminum. The piece of cover film 50 can also be provided with a print, for example for informational and / or advertising purposes.

The invention can be summarized as follows. A package 1 comprises a whole of a container 10 with an open side and an annular lid edge 20 which is located on the open side 13 of the container 10 on an outer peripheral edge 16 of the container 10, and which is provided by means of a relatively weak break-through portion 30 is connected to the tray 10. For the purpose of manufacturing the package 1, a mold 41 with an inner surface 42 formed to a lower surface 17 of the package 1 is provided. A sheet 40 is also provided and placed in the mold 41, a movement of the sheet 40 being forced to bring the sheet 40 into a state in which it abuts at least the inner surface 42 of the mold 41 and thus an intermediate mold 2 of the package 1, with the tray 10 and the lid edge 20 of the package 1. Material of a portion 3 of the intermediate form 2 of the package 1 which is located at the location of a transition from the tray 10 to the lid edge 20, is removed to realize the breakthrough portion 30 of the package 1, whereby the package 1 of surrounding material 43 is detached from the sheet 40. Furthermore, a piece of cover foil 50 is provided and at least connected to the cover edge 20.

21

The break-through portion 30 can be broken prior to the application of the piece of cover foil 50, but this is not necessarily necessary. In any case, the lid edge 20 and the tray 10 are preferably adapted to be brought into engagement with each other by means of a snap connection after they no longer form an integral whole with each other via the break-through part 30.

Claims (29)

A method for manufacturing a package (1) comprising a whole of a container (10) with an open side (13) and an annular lid edge (20) located on the open side (13) of the container (10) is located on an outer peripheral edge (16) of the tray (10), and which is connected to the tray (10) by means of a relatively weak break-through portion (30), wherein a mold (41) with an inner surface (42) facing a bottom surface (17) of the package (1) is formed, provided, wherein a sheet (40) is provided and placed in the mold (41), a movement of the sheet (40) being forced to cause the sheet ( 40) into a state in which it is at least against the inner surface (42) of the mold (41) and is thus an intermediate form (2) of the package (1), with the tray (10) and the lid edge ( 20) of the package (1), and wherein material of a portion (3) of the intermediate mold (2) which is located at the location of a transition of the tray (10) that the lid edge (20) is located, is removed in order to realize the breakthrough portion (30) of the package (1). 15 A method according to claim 1, wherein the portion (3) of the intermediate mold (2) located at the transition from the tray (10) to the lid edge (20) is formed as a curved portion with a convex mold on the lower surface (17) of the intermediate mold (2), that is, the surface (17) of the intermediate mold (2) that faces the inner surface (42) of the mold (41), and a concave mold on an upper surface (18) of the intermediate mold (2). 3. Method according to claim 1 or 2, wherein the package (1) of surrounding material (43) is detached from the sheet (40), and wherein the removal of material from the part (3) of the intermediate mold (2) is located at the location of the transition from the tray (10) to the lid edge (20), while this is carried out simultaneously. 4. Method as claimed in any of the claims 1-3, wherein during removal of material from the part (3) of the intermediate mold (2) which is situated at the transition from the tray (10) to the lid edge (20) said portion (3) relative to the tray (10) and the lid edge (20) is made thinner. 5. Method as claimed in any of the claims 1-4, wherein during removal of material from the part (3) of the intermediate mold (2) which is situated at the transition from the tray (10) to the lid edge (20) there are openings (31) between the receptacle (10) and the lid edge (20) at defined places. The method of any one of claims 1-5, wherein the sheet (40) is heated before the sheet (40) is moved toward the inner surface (42) of the mold (41). A method according to any of claims 1-6, wherein pressure difference 15 is applied over the sheet (40) to move the sheet (40) against the inner surface (42) of the mold (41). A method according to claim 7, wherein an underpressure is created on one side of the sheet (40) that faces the inner surface (42) of the mold (40). 20 A method according to any of claims 1-8, wherein a piece of cover film (50) is provided and connected to the lid edge (20) to close the tray (10). A method according to any of claims 1-8, wherein the lid edge (20) and the tray (10) of the package (1) are detached from each other by a limited mutual movement of the lid rim (20) and the tray (10). ), wherein the breakthrough portion (30) is broken, and wherein a piece of cover film (50) is provided and at least is connected to the lid edge (20) to close the tray (10). The method of claim 10, wherein the piece of cover film (50) is connected at least to the lid edge (20) during the mutual movement of the lid edge (20) and the tray (10). The method according to claim 10, wherein the piece of cover film (50) is connected at least to the lid edge (20) once the lid edge (20) and the tray (10) have been detached from each other and the mutual movement has ended. 5 A method according to any of claims 10-12, wherein the mutual movement of the lid edge (20) and the tray (10) is terminated when a surface (24) of the lid edge (20) and a peripheral surface (15) of the receptacle (10) located on the open side (13) of the receptacle (10) is at a substantially equal level. A method according to any of claims 10-13, wherein the piece of cover film (50) is connected to both the tray (10) and the lid edge (20). A method according to claim 14, wherein a stronger connection between the piece of cover foil (50) and the lid edge (20) is realized than between the piece of cover foil (50) and the tray (10). A method according to any of claims 9-15, wherein the connection between the piece of cover film (50) and at least the cover edge (20) is established under the influence of local heat supply. 17. Method according to any of claims 9-16, wherein means (61) are used to support at least the lid edge (20) during the connection between the piece of cover film (50) and at least the lid edge (20). 18. Method according to any of claims 9-17, wherein material to be packaged is placed in the tray (10) before the piece of cover film (50) is connected to at least the lid edge (20). A package (1) comprising a whole of a container (10) with an open side (13) and an annular lid edge (20) which is located on the open side (13) of the container (10) on an outer peripheral edge (16). ) of the tray (10), and which is connected to the tray (10) by means of a relatively weak break-through portion (30), which is entirely formed on the basis of a sheet (40), wherein at the break-through portion ( 30) material is removed from the sheet (40), and wherein the sheet (40) is curved at the area of the break-through portion (30), having a convex shape on a lower surface (17) of the package (1), and a concave shape on an upper surface (18) of the package (1). A package (1) according to claim 19, wherein at the break-through section (30) the sheet (40) is made thinner relative to the tray (10) and the lid edge 10 (20). The package (1) according to claim 19 or 20, wherein the breakthrough portion (30) is provided with openings (31). A package (1) according to any of claims 19-21, comprising a piece of cover film (50) which is connected to the lid edge (20) and closes the tray (10). The package (1) according to claim 22, wherein material is contained in the tray (10). 20 A package (1) comprising a whole of a container (10) with an open side (13) and an annular lid edge (20) surrounding the container (10) on the open side (13) of the container (10) ), and which is connected by means of a snap connection to the tray (10), which is entirely formed on the basis of a sheet (40), the lid edge (20) and the tray (10) being broken away from each other, an inner peripheral edge (25) of the lid edge (20) is partially curved, and an outer peripheral edge (16) of the tray (10) is also partially curved. 25. Package (1) according to claim 24, comprising a piece of cover foil (50) which is at least connected to the lid edge (20) and closes the tray (10). The package (1) of claim 25, wherein a face (24) of the lid edge (20) and a peripheral face (15) of the tray (10) located on the open side (13) of the tray (10) , are at practically the same level. The package (1) according to claim 25 or 26, wherein the piece of cover film (50) is connected to both the tray (10) and the lid edge (20). A package (1) according to claim 27, wherein a connection between the piece of cover foil (50) and the lid edge (20) is stronger than a connection between the piece of cover foil (50) and the tray (10). 29. Package (1) according to any of claims 25-28, wherein material is present in the tray (10).