WO2004080818A2

WO2004080818A2 - Receptacle for fragile items, particularly fruit and vegetables

Info

Publication number: WO2004080818A2
Application number: PCT/IB2004/001229
Authority: WO
Inventors: Henri Haist
Original assignee: Hbv Innova Ag
Priority date: 2003-03-12
Filing date: 2004-03-10
Publication date: 2004-09-23
Also published as: WO2004080818A3; EP1633652A2; FR2852300A1

Abstract

The invention relates to a receptacle for fragile items, particularly fruit and vegetables. The receptacle (1) is produced by shaping a sheet of thermoplastic synthetic material and comprises one or more recesses (3) of any shape provided over at least part of the lower or side walls (2) thereof and projecting into the receptacle in such a way that they define a plurality of contact points for the items in the receptacle, wherein said recesses are sealed with a film (6) affixed to the outside of the receptacle (1) in such a way that air is trapped inside the recesses (3), thereby constituting a shock- and vibration-absorbing pad. In one of the embodiments of the invention, the material used to make the walls of the recesses is sufficiently locally stretched to become semi-rigid or even flexible so as to define deformable contact points for the items in the receptacle.

Description

RECEPTACLE FOR FRAGILE PRODUCTS, ESPECIALLY FOR FRUITS AND VEGETABLES

The present invention relates to a receptacle for fragile products. It applies more particularly, but not exclusively, to the field of packaging of fruits and vegetables.

In general, the packaging of fragile products poses numerous problems of protection against shocks and vibrations to which they are exposed during transport and handling carried out in the distribution circuit, then by the consumer.

In the specific field of fruit and vegetables, it is difficult to transport fruit in perfect condition throughout the supply chain from the place of harvest to the point of sale, then to maintain the products in good condition until by the time they are consumed.

It is for this reason that most fruits are today marketed in a state of ripening which is not very advanced, which allows them to better resist the mechanical stresses encountered during this logistic cycle of routing. However, certain categories of consumers, more and more numerous, are demanding quality fruits, so-called "ripe to maturity" fruits, that is to say fruits marketed in a state of maturity sufficient to present optimal organoleptic qualities. : appearance, hygiene, taste, texture, odor, quality of the juice, etc.

All players in the fruit and vegetable sector are therefore looking for effective solutions to meet this consumer expectation.

Current production techniques, post-harvest pre-treatment, conservation and distribution make it possible to guarantee the delivery to the end of the chain of a fruit that meets these quality requirements. The main remaining difficulty comes from conditioning. Indeed, current packaging techniques do not provide sufficient protection for ripe fruit, especially during transport.

Most of the fruits concerned by this quality demand are sold in thermoformed packaging of the "tray" type, which allow on the one hand to obtain an attractive presentation due to their transparency, and on the other hand to protect the fruits well. from a hygienic point of view because they are closed packages.

The problem encountered lies in the fact that the walls of these packages are rigid, in order to maintain their shape. The fruits are therefore permanently supported on the bottom and on the side walls, which generates significant local pressures at the points of contact which can seriously damage ripe or fragile fruits, such as strawberries, currants or exotic fruits. .

Various methods are known for solving this problem.

The best known and most used solution consists in introducing into the bottom of the trays a rectangle cut from a protective film with air bubbles, so as to constitute a mattress which protects the fruits from vertical shocks. The drawback of this solution is that it requires additional operations for cutting, placing, and possibly bonding the mattress, which generates very high costs, if they are compared to the low unit cost price of each packaging. In addition, this solution does not entirely solve the problem, because it only provides protection for vertical impacts, but does not protect the fruit against impact on the side walls of the packaging.

It is interesting, with regard to the invention described below, to recall that the protective films are produced from a flexible plastic film in which the bubbles have been hot preformed, on which a flexible film has been laminated , so as to trap air between the two films. We see that the mattress is always positioned in the bottom of the trays with its flat face upwards and the bubbles below, while it would be better to position the bubbles upwards, so as to maximize the points of contact - which distributes the reaction exerted by the packaging to inertial forces and reduces local pressure on each point of contact -, to ensure better wedging of the fruits, thanks to the lateral supports that the fruit can find on each bubble in contact with it, and to avoid that the fruits remain in contact with the juice which can run off, which is likely to cause incidences of rotting.

US Pat. No. 3,610,509 describes a package, the bottom of which consists of an expanded foam sheet serving as a mattress, the fruits then being sandwiched between this mattress and an upper flexible film which blocks their movement. The disadvantage of this solution is that it forces the fruit to be compressed between the bottom and the upper film in order to keep it in position, which risks damaging the fruit if it is too fragile. In addition, it uses different materials, which is a drawback if environmental criteria are taken into account in the design of packaging.

Patent EP 0 823 387 A1 describes a wedging process specially intended for the packaging of bananas consisting of a chain of air cushions which are placed manually between the fruits in order to wedge them. This solution, if it responds well to the specific problem of bananas, is ill-suited to the packaging of round fruits such as peaches, nectarines, apricots or tomatoes, and to that of small fruits such as strawberries, grapes, raspberries or currants.

Patent EP 0 378 783 A1 describes a package consisting of a rigid and concave outer wall, in which a flexible film is welded at various points, so as to constitute “cushions” of air capable of absorbing shocks when the fruits come into contact with this flexible wall.

The idea is interesting but has not been commercially successful because its implementation requires complex specific tools, which makes the process relatively expensive and technically quite difficult to master on the scale of an industrial production. In addition, this solution does not guarantee that the contact pressure will be well distributed over the entire surface of the wall of the packaging, since each cushion individually has a flat and slightly deformable contact surface, so that the fruit has tendency to crash locally on this wall as on a rigid wall. It is interesting to note that in this process, the lower concavity of the packaging is used to form air cushions inside the volume of the latter, by stretching a membrane between various connection points located at the inside the packaging, which basically differentiates this solution from that which is proposed by the invention described below.

Finally, the patents DE 197 58 126 and DE 197 58 127 describe a folding box comprising a zone provided with concentric orifices allowing the passage of tubular elements, and the side walls of which include sheets forming a series of folds, which, when 'they are superimposed, allow to stiffen the periphery of the box. Consolidation of the packaging is thus obtained by superposition with an offset of the folds of the inserted sheet. According to a variant, the wedging and the consolidation are carried out by introduction into the box of sheets comprising bosses directed inwards.

These solutions are undoubtedly effective, but they impose a modification of the packaging before use, multiple and complex preparation operations to fold and set up the external wedging elements, and therefore additional costs.

The present invention aims to provide a solution that is both effective, simple to implement and economically efficient to the problems described above.

To this end, it offers a receptacle made from a sheet of thermoplastic material, consisting of a rigid external wall formed according to the conventional thermoforming process, in which cavities are produced locally whose concavity is oriented towards the outside. of the receptacle, so as to constitute a plurality of support points for the packaged products, which makes it possible to reduce the contact pressure and to ensure better timing. According to another characteristic of the invention, said cavities can be closed by adding a film on the external surface of the receptacle, so as to constitute air bubbles serving as shock absorber for the packaged products, which increases the effectiveness of protection.

The external film making it possible to close the bubbles can be a plastic film glued or heat sealed, or else an adhesive label, possibly printed, based on paper or plastic. This film can be added at the time of manufacture of the receptacle, just after the thermoforming operation, or else at the time of packaging. This last option makes it possible to reduce the transport and storage volumes by reducing the stacking step of the empty receptacles, and it makes it possible to affix a printed film carrying variable graphic information according to the nature of the product packaged, the date or the place. packaging, etc.

According to a variant, during the constitution of the cavities, a greater material stretching is carried out locally than in the current zone, for example by suction, so that the walls of the stretched cavities are no longer rigid but semi-rigid, or even flexible, and constitute a plurality of deformable support points for the packaged products, which makes it possible to better protect them from shocks and vibrations.

The invention will be better understood through the description below of various embodiments, with reference to the accompanying drawings, in which:

FIGS. 1a and 1b show in section and in perspective a receptacle produced according to the invention, with an attached outer film,

FIG. 2 is a sectional view of a thermoforming mold making it possible to cause a local stretching of material, so as to produce flexible cavities according to the invention,

- Figure 3 shows an installation for manufacturing the receptacles made according to the invention, in which the outer film is continuously reported just after the forming of the receptacle and heat sealed - Figures 4a and 4b show the comparison between a stack of receptacles made according to the invention in which the outer film is attached at the time of packaging with a stack of receptacles in which the film is attached at the time of manufacture of the receptacle.

FIG. 5 shows a receptacle produced according to the invention in which the cavities are grooves arranged in the bottom of the receptacle,

FIG. 6 shows a receptacle produced according to the invention comprising both cavities in the bottom of the receptacle and grooves on the side walls of the receptacle,

FIG. 7 shows in section a receptacle produced according to the invention in which the cavities have a variable height, in order to maintain a good distribution of the packaged products over the entire surface of the bottom,

FIG. 8 shows in section a receptacle produced according to the invention in which the cavities have a shape adapted to the shape of the packaged products, in order to ensure perfect wedging,

FIG. 9 shows a receptacle produced according to the invention in which the cavities are telescopic,

FIG. 10 shows a receptacle produced according to the invention in which the outer film itself consists of a rigid or semi-rigid thermoformed film, which allows for example to stiffen the bottom of the receptacle, and

- Figure 11 shows a receptacle made according to the invention in which the cavities contain a liquid or powder product having an active function for the preservation of products.

The receptacles according to the invention, represented by a tray designated under the general reference (1) and an example of which is shown in section and in perspective in FIGS. 1a and 1b, are produced according to conventional thermoforming techniques. The invention makes it possible to obtain excellent protection of the products against shock and vibration, and this thanks to two characteristics.

The first characteristic is that at least one of the external walls (2) of the receptacle (1) comprises a plurality of cavities (3) whose bottom (4) is semi-rigid, even flexible. In the example shown in (Figures 1a and 1b, the cavities (3) are formed on the base of the receptacle (1). They could just as easily be formed on one or more of the side walls, without this modifying the explanations given below.

An advantageous method for obtaining cavities with flexible walls consists in locally causing a stretching of material in the zones of cavities greater than in the current zone, for example by means of suction channels (5) located at the bottom of each cavity ( 3), as shown in FIG. 2 which shows in section a thermoforming mold making it possible to cause a local stretching of material to produce flexible cavities according to the invention.

The second characteristic is that there is attached to the outside of the wall (2) of the receptacle a film (6) glued or heat sealed, so as to close the volume of the cavities (3) and to trap air inside.

Each closed cavity thus formed becomes an air cushion capable of deforming when the product rests on it, and therefore of ensuring a wedging function by adapting to the exact shape of each product, to produce an effect of shock absorption, due to its ability to deform under the effect of a pressure exerted by the product, to produce an elastic reaction to the stresses exerted by the products on the walls, which considerably improves the protective effect against shock and vibration,

The result obtained, even if the process for obtaining it differs completely, is comparable to an air bubble mattress integrated into the walls of the receptacle, the latter being able to be further adapted to the particular characteristics of weight, shapes and dimensions of the packaged product. . It will be advantageous to choose an external film of sufficient rigidity so that, when the product exerts pressure on the wall, the flexible internal face of the cavity (3) deforms and the external film (6) does not deform or little, so that the trapped air is compressed and can play its role of elastic damper.

The invention can be implemented in a simple and inexpensive manner on the scale of industrial mass production.

The film (6) can be printed before installation, so as to allow graphic and informative communication intended for the consumer. It can consist, for example, of an adhesive label made of paper or plastic. It can also consist of a plastic film which is preferably, but not necessarily, identical to the material which constitutes the rigid body of the receptacle. In this case, the film can be glued, welded or heat sealed on the outer wall of the receptacle.

The film (6) can be continuously and automatically added immediately after the receptacle has been formed and heat sealed, as shown in FIG. 3.

The film (6) can also be added at the time of packaging of the products, manually or using a heat-sealing or labeling machine, depending on the volumes and production rates. In this case, the transport and storage volume is reduced because the stacking pitch of the receptacles (1) is limited, because the cavities (3) of the superimposed receptacles can be nested one inside the other, as illustrate it in Figures 4a and 4b.

In addition, this option makes it possible to place a personalized label according to each product packaged, while using a single packaging model for the entire range, which makes it possible to rationalize the supply of packaging and the management of packaging stocks. .

The cavities (3) can have any shape. They can, for example, be in hemispherical or ovoid form, or take the form of longitudinal grooves (3 ′), as shown in FIG. 5. It is possible in this case to generate in the bottom (2) of the container (1) parallel grooves or else interleaved grooves in the form of braces.

As already mentioned above, the cavities (3) can be located on the bottom (2) of the receptacle (1) or on the side walls (2 '), so as to absorb shocks side, as shown in figure 6.

It is moreover interesting to note that the packages of this type all have a certain taper open upwards, due to the release requirements.

Because of this taper, the balancing of gravity forces naturally tends to crush the fruits against each other and on the side walls, especially when it comes to small fruits such as strawberries, cherries or currants . The presence of cavities on the side walls effectively solves this problem.

When the cavities (3) are located on the side walls (2 '), it is preferable to give them the form of grooves (3') oriented vertically, as shown in Figure 6, to allow easy removal of the receptacle after forming. However, there is nothing to prevent horizontally oriented grooves or point cavities being formed on the side walls, for example by using a mold comprising retractable drawers to allow demolding.

Of course, depending on the applications, it is possible to produce receptacles comprising both cavities on the bottom and on the side walls, as also shown in FIG. 6.

The cavities (3) can all be identical or have different shapes and heights. We can for example alternate cavities of low height with cavities of greater height, as shown in Figure 7, so as to ensure a good distribution of products (9) packaged over the entire surface of the bottom (2) and better wedging, especially when these are small. When the packaged product (9) has a relatively constant and repetitive shape from one product to another, the cavities (3) can have shapes specifically adapted to the shape of the product, so as to ensure perfect wedging, as it is shown in Figure 8.

This characteristic is common when the packaged product is an industrial manufactured product, such as for example a light bulb, but it is rarely encountered when it comes to fruits or vegetables, which are natural agricultural products, of random shape.

However, genetic selection techniques and post-harvest sizing make it possible to obtain products whose geometry is relatively constant, in particular for round fruits such as tomato, peach or nectarine and large fruits such as avocado, mango or the melon. On the other hand, this characteristic does not apply well to small fruits or to very irregular fruits like grapes.

When the cavities are rigid, their function consists in ensuring the setting of the products and distributing the reaction of the walls over several contact points.

It is possible to produce cavities capable of deforming when the products come into contact with them, which, on the one hand, ensures better wedging due to the automatic adaptation of the packaging to the exact shape of the packaged products and, on the other hand, makes it possible to obtain a shock and vibration damping effect.

A solution shown in FIG. 9 consists, for example, in giving the cavities (3) the shape of a pyramid (3 "), the successive stages (7) of which are capable of falling into each other telescopically when the product s press at the end.

A possible variant consists in closing the cavities (3) from the outside not with a flexible or semi-rigid film, but with a sheet (6 ') which has itself been previously thermoformed, so as to obtain specific results. research. This variant allows for example, as shown in Figure 10, to strengthen the rigidity of the bottom (2) of the receptacle (1) by stiffeners. It is particularly advantageous when the weight of the packaged products is large or when the surface of the receptacle is large relative to its height, which harms the rigidity of the assembly.

It also allows, for example, to constitute support legs in the bottom or drainage channels capable of receiving the juice which flows from the fruit.

Finally, another possible variant shown in FIG. 11 consists in introducing inside the cavities (3) a flowable product (8) such as a powder or a liquid which can perform an additional function in the receptacle, such as, for example example, a moisture or oxygen absorber which improves the shelf life of packaged products. This variant assumes that the film constituting the receptacle is not impermeable to the active product, and allows its diffusion inside the receptacle, either by natural permeability, or by means of micro-perforations previously made.

Although the invention has been described above with reference to various modes and implementation, it may receive various variant embodiments without departing from the scope defined by the claims.

Claims

1. Receptacle intended for the packaging of fragile products, in particular but not exclusively for the packaging of fruits and vegetables, produced by forming a film of thermoplastic synthetic material and characterized in that: it comprises on at least one of its lower walls or lateral

(2) one or more cavities (3) of any shape, the concavity of which is oriented towards the interior of the receptacle (1), so as to constitute a plurality of contact points for the packaged products, said cavities (3) are closed by a film (4) attached to the outside of the receptacle (1), so as to trap the air inside the cavities (3) to form a cushion for shock and vibration absorption.

2. Receptacle according to claim 1, characterized in that the material constituting the wall of the cavities (3) has undergone a local stretching sufficiently large to become semi-rigid, so as to constitute deformable support points for the packaged products.

3. Receptacle according to claims 1 or 2, characterized in that the cavities (3) consist of grooves (3 ').

4. Receptacle according to claims 1 or 2, characterized in that the cavities (3) consist of pyramids (3 ") whose successive stages

(7) can be retracted one inside the other

5. Receptacle according to any one of the preceding claims, characterized in that cavities (3) are provided on the bottom (2) of the receptacle (1).

6. Receptacle according to any one of the preceding claims, characterized in that cavities (3) are provided on the side walls (2 ') of the receptacle (1).

7. Receptacle according to any one of the preceding claims, characterized in that the film (6) for closing the cavities (3) is heat sealed on the external wall (2) of the receptacle (1).

8. Receptacle according to one of claims 1 to 6, characterized in that the film (6) for closing the cavities (3) is an adhesive label.

9. Receptacle according to one of claims 1 to 6, characterized in that the film (6) for closing the cavities (3) consists of a flexible plastic film.

10. Receptacle according to one of claims 1 to 6, characterized in that the film (6) for closing the cavities (3) consists of a film of semi-rigid plastic.

11. Receptacle according to any one of the preceding claims, characterized in that the film (6) for closing the cavities (3) is printed.

12. Receptacle according to any one of the preceding claims, characterized in that the cavities (3) are filled by means of a substance (8) preserving the packaged products.