Method and apparatus for packaging articles and use of a film for this method

Abstract

In one method for packaging an object in a thermally shrinkable barrier film, a carrier with the object on it is completely wrapped in the barrier film. This involves either creating a negative pressure in the film bag and then sealing the film bag with the negative pressure inside. Alternatively, the finished film bag can have a pressure relief valve attached to the barrier film or a vent hole that is sealed hermetically after shrinking. The film bag is sealed by thermally welding at least two superimposed layers of the barrier film together, and then the barrier film is thermally shrinked to tightly fit the film bag against the carrier with the object on it. The barrier film is two-layered with a thin layer of EVOH film in between to ensure recyclability.

Description

Area of ​​application and state of the art

[0001] The invention relates to a method for packaging an object in a film or with a film, wherein the object lies on a carrier, and this carrier and the object are then wrapped in the film. Furthermore, the invention relates to the use of a so-called barrier film for packaging an object on a carrier according to this method. Finally, the invention also relates to a device with which the inventive method can be carried out.

[0002] It is known, for example, to package food items directly and solely in film. It is also known to place food items on a carrier, for example made of cardboard or a multi-layer plastic tray, with the carrier having a wide, circumferential edge at the top. A multi-layer film is then glued or welded onto this edge for sealing. For this purpose, this film is designed in such a way that it does not allow germs, bacteria, or excessive oxygen to penetrate from the outside to the inside of the food to be packaged. Furthermore, some of these films are relatively thick to ensure that the aforementioned type of connection to the edge of the carrier is permanent and stable. The disadvantage of this multi-layer construction is that the material is not recyclable. A lid can be made of LDPE / EVOH / PP with a thickness of 55 µm, and a carrier can be made of PET or LDPE.

[0003] Furthermore, so-called EVOH shrink films, also known as barrier films, are known from EP 3 530 457 A1, for example. These can also be used for packaging foodstuffs placed on carriers. After wrapping or sealing a package, they can be thermally shrunk in a conventional manner. Task and solution

[0004] The invention is based on the object of creating a method as mentioned above, a corresponding use and a corresponding device with which problems of the prior art can be solved and in particular it is possible to package foodstuffs as objects on a carrier safely, durably and as germ-free as possible or as well as possible, wherein preferably the packaging is as completely recyclable as possible, a carrier is possibly compostable.

[0005] This object is achieved by a method having the features of claim 1, by a use having the features of claim 14, and by a device having the features of claim 15. Advantageous and preferred embodiments of the invention are the subject of the further claims and are explained in more detail below. Some of the features are described only for the method, only for the use, or only for the device. However, they are intended to be able to apply independently and independently of one another to the method, to such a use, and to a corresponding device. The wording of the claims is incorporated into the content of the description by express reference.

[0006] The method serves to package an object in a film, wherein the object is arranged on a carrier. It is also possible for several, in particular similar or identical, objects to be packaged on a single carrier. Preferably, however, it is a single carrier in a single film package. The film is an aforementioned barrier film, preferably an EVOH film, optionally also a multilayer film with a layer of EVOH film, advantageously as a middle layer between two other film layers. It is thermally shrinkable and difficult or impossible for bacteria and germs to penetrate. Likewise, it can be virtually impervious to atmospheric gases such as oxygen, carbon dioxide, or the like. The packaging method comprises the following steps.

[0007] In step A), a carrier is provided on which at least one of the aforementioned objects is located. The carrier projects laterally beyond the object, at least when viewed from above. Advantageously, the carrier can also be higher than the object, i.e., project beyond it, although this is not mandatory. Alternatively, the carrier can be adapted to the object or objects to be packaged, whereby it can also be smaller or the same size. The size of the carrier should deviate from the size of the object by a maximum of 10% in the contact area. Preferably, the carrier is larger or projects just beyond the object.

[0008] In step B), the carrier with the object on it is completely wrapped or wrapped in the barrier film, meaning it is completely enclosed in the film. The film may still be open in at least one spot or on one side of the carrier. On the one hand, this is an intermediate stage during packaging anyway. On the other hand, it can be used because it then offers several options for sealing the film or the resulting film bag with the carrier and object inside.

[0009] The film bag is then generally produced or sealed. A first option for sealing the barrier film around the carrier with the object on it is to create a vacuum in the film bag thus formed. This can be achieved in several ways, which are explained in more detail below. The vacuum serves to ensure that the film bag adapts somewhat, largely, or completely to the carrier and the object on it. Furthermore, it helps to shrink the barrier film or film bag more effectively, which is explained in more detail below. In any case, according to step C), the film bag is sealed with a vacuum inside it, whereby the vacuum can advantageously be between 0.1 bar and 0.5 bar.

[0010] As an alternative to the aforementioned step C), in a step D), a complete closure of the barrier film around the carrier with the object thereon to form a film bag can be provided, with a pressure relief valve being attached to the finished film bag. Such a pressure relief valve can be designed in a similar way to that known, for example, from packaging for coffee beans or the like. It can advantageously be attached to an upper side of the film bag, particularly advantageously offset to one side or attached such that it is not located at the highest point of the packaging or film bag due to the packaged object. This pressure relief valve also serves for the subsequent thermal shrinkage.

[0011] According to a third possibility, according to a step E), which can be carried out alternatively to step C) or alternatively to step D), a vent hole can be created or present in the film bag formed from sealed barrier film. This can be done, for example, by simple perforation. The film bag formed in this way can release excess pressure and heated air from the film bag through this at least one vent hole during the subsequent step of thermally shrinking the film bag. After the barrier film has been thermally shrinked, the vent hole is hermetically sealed again, for example by means of a patch or an adhesive label or the like, which can consist of barrier film in order to retain the desired advantageous properties in this area as well, or can consist of another material or another film.

[0012] The film bag is sealed, or the barrier film forms the film bag during sealing, by placing at least two layers of barrier film on top of each other and joining them by thermal welding, i.e., the film bag is thermally welded. This can generally be done in a known manner, as explained in more detail below.

[0013] Subsequently, in step F), the barrier film or film bag is heated to shrink the barrier film through thermal action. This causes the film bag formed by the film bag to fit tightly against the carrier with the object on it. This results in a more visually appealing, mechanically easier to handle and grasp package with the carrier and object inside, since the barrier film, stretched over or onto the carrier, further stabilizes it. This results in a fundamentally highly practical packaging.

[0014] During thermal exposure, any air trapped in the film bag will generally expand due to the heating. If a negative pressure or sufficient negative pressure is created in the film bag as per step C), this negative pressure atmosphere will not expand significantly even upon heating during thermal shrinkage. At least, this expansion is not so significant that it would disrupt or impair the thermal shrinkage process itself. After cooling, the carrier with the at least one object on it is tightly and securely wrapped in the film bag, preferably under tension.

[0015] In step D), the pressure relief valve serves to release the non-pressurized air in the film bag, which expands due to heating, to the outside. Since the pressure relief valve is a one-way valve, no ambient air is drawn in during cooling, allowing the barrier film to shrink very effectively, and the result is packaging in a thermally shrunk film bag, just as in step C). The pressure relief valve simply remains attached to the film bag.

[0016] In the procedure according to step E), the at least one vent hole serves, similar to the pressure relief valve, to equalize or release the excess pressure generated due to the heating of the air in the film bag. After shrinking, preferably before complete cooling, the vent hole is closed or glued or taped. This prevents gases, bacteria, germs, etc., from entering through this vent hole. Furthermore, by closing it before complete cooling, a negative pressure can also be achieved, albeit a relatively small or weak negative pressure.

[0017] Thus, within the scope of the invention, there are several possibilities to achieve the goal of an object wrapped in a shrunk barrier film on a carrier.

[0018] The measures of step C), step D) or step E) each serve to reduce or prevent thermal shrinkage of the barrier film with temperature-induced expansion of air or gases contained in the film bag.

[0019] As a further alternative to steps C), D) and E), gas and / or air can be forced out of the film bag before it is completely closed, either partially or largely, for example 10% to 40% or even up to 60%. This can preferably be done by applying pressure to the film bag from one side, in particular from above. This is particularly advantageous if it is done over a large area and is yielding or flexible, so that excess air or gas can be forced out of the film bag or the bag is slightly flattened. The effect is similar to that when suction is drawn out of the film bag shortly before it is completely closed. During the subsequent thermal shrinkage, the sealed film bag then expands to a lesser extent or not at all due to the air or gas it contains. This ultimately also allows for better thermal shrinkage.

[0020] In an embodiment of the invention, the barrier film can have a thickness of between 10 µm and 40 µm, preferably between 15 µm and 30 µm. The relatively low thickness can reduce the amount of plastic waste generated. The film for the film bag or for the packaging can consist of two separate webs of flat film, whereby the two webs advantageously have the same width and are guided over one another with some spacing, with the carrier with the object to be packaged in or on it lying between the two webs. The process then involves forming four airtight weld seams to produce the film bag, whereby these weld seams preferably adjoin one another and run continuously around the film bag.Alternatively, a so-called half-tube can be formed from a single web of flat film, so that a single web of flat film is folded onto itself along one long side. The result is a so-called half-tube. The carrier with the object inside is then inserted into this half-tube in order to ultimately be packaged as a film bag, with only three weld seams being formed for this purpose. Where in a process with two separate webs of flat film the fourth weld seam was, the film web is, so to speak, continuous due to the folding. The weld seams formed are then located on the end sides of a package or film bag in the direction of travel and laterally along one of the long sides. In a further embodiment of the invention, a barrier film is advantageously sealable orcan be sealed or welded by heat, either with other materials or, advantageously, with itself. For this purpose, it can have two film layers, advantageously made of PE, which have a so-called barrier layer between them.

[0021] These film layers and the barrier layer are firmly bonded together. The barrier film is co-extruded, which is particularly advantageous for thermal shrinkage.

[0022] In a further embodiment of the invention, it can be provided that the negative pressure is created and maintained during complete closing. It can fluctuate during this process. Under certain circumstances, the negative pressure can also be created or an attempt can be made to actively create it until shortly before the film bag is closed or the film layers are welded, for example by pressing on the film bag or by suction, but this is then stopped. Shortly after stopping, preferably a maximum of 2 seconds or a maximum of 1 second afterwards, the film bag can then be completely closed. Complete pressure equalization cannot take place within this very short time, so that a sufficient negative pressure still exists inside the sealed film bag. In this way, air can still be sucked out or escape through the last remaining opening in the film bag, which is then only closed at the last moment.

[0023] In an advantageous embodiment of the invention, the barrier film can be shrinked by thermal action. Hot air, steam, or a water bath can be used for this purpose in a conventional manner; it can advantageously be carried out in a shrink tunnel mentioned above. Particularly advantageously, shrinking takes place as the film bag with the carrier and the article inside passes through.

[0024] Preferably, the negative pressure that has been generated or exists in the film bag in step C) after complete sealing and before shrinking of the barrier film can be between 0.01 bar and 0.9 bar, particularly preferably between 0.1 bar and 0.5 bar. This is sufficient to keep the expansion of air in the sealed film bag in a subsequent thermal shrinking process so low that it does not negatively affect or prevent the shrinkage of the film.

[0025] In an advantageous embodiment of the invention, it can be provided that the carrier with the object thereon is first inserted into the barrier film in such a way that the barrier film is below the carrier and, on a first lateral side, overlaps continuously and uninterruptedly upwards onto the carrier and the object thereon. On the opposite, second lateral side, both film layers can protrude beyond the carrier and the object thereon. This is then a so-called film half-tube, which can be produced, for example, according to EP 806 346 A2 and has the advantage that only a single film web is required and needs to be welded along only a single lateral side, namely the first lateral side.The two film layers can then be welded together on this second lateral side, in particular at a distance from the second lateral side of the carrier that is less than 20% or less than 10% of the distance between the two lateral sides. Any film overhang outside the film bag can be cut off.

[0026] In an advantageous embodiment of the invention, the welding takes place at least on the second lateral side, advantageously on both lateral sides, in a continuous process. Particularly advantageously, it takes place constantly or at a constant speed, or at least without interruption.

[0027] During packaging in the barrier film or film bag, the carrier with the object thereon can be moved along a transport direction, with the two film layers being connected to one another in a transverse direction running transversely to this transport direction or being connected by welding. This can already have been done on a front side of the carrier as seen in the transport direction, which is also known in serial packaging from the aforementioned prior art. Preferably, the film bag can be finally sealed by welding the two film layers together on a rear side opposite the front side; this is essentially the final weld seam.

[0028] In one embodiment of the invention, the interior of the foil bag can contain normal air, i.e., no protective gas, advantageously with the negative pressure. This saves the effort that would be significant, especially when applying or generating the negative pressure.

[0029] Alternatively, the interior of the film bag can contain a protective gas, for example a common protective gas for food such as carbon dioxide or nitrogen, advantageously also with a negative pressure. Nevertheless, the aforementioned negative pressure can still be present here. Yet another option is dry ice, which is placed inside the package. In some applications, it is easier to handle than gaseous carbon dioxide. When the dry ice outgasses, carbon dioxide is released, which completely replaces the air inside the film bag, leaving an atmosphere of 100% carbon dioxide in the film bag. This escaping air or excess carbon dioxide must escape from the film bag via the pressure relief valve or the vent hole until the dry ice has completely evaporated.

[0030] In an embodiment of the invention, the negative pressure according to step C) can be generated in the film bag by inserting or placing an elongated, inherently stable pipe or other suction pipe or hose into the not yet fully sealed film bag. This can then be used to extract air from the film bag or to generate the negative pressure, with the air being extracted, in particular, while the film bag is being sealed. The pipe should be removed before the film bag is completely sealed, i.e., while the film bag is only partially sealed.

[0031] In another embodiment of the invention, the negative pressure according to step C) can be generated in the film bag by generating a negative pressure in a laterally sealed film tube for several film bags. In this film tube, several objects are always lined up one behind the other and are advantageously moved largely continuously. A welding stamp running transversely to the longitudinal direction or a so-called cross-welding device can then seal or close and separate the first object in the film tube outside of a functional unit generating the negative pressure. The cross-welding device should preferably be designed to move, at least for a short distance, so that it can seal or close and separate while moving. In this way, the movement of the film bags or the objects to be packaged does not need to be interrupted. An aforementioned suction pipe or the like.To generate the negative pressure, it can then stand immobile or statically in the film tube, advantageously in the area of ​​the cross-sealing device, particularly advantageously 10 mm to 70 mm, for example 40 mm, away from it.

[0032] Such a transverse welding device can generally be provided to divide the film bags in the longitudinal direction and, above all, to weld and thus also close them.

[0033] In yet another embodiment of the invention, as an alternative to steps C), D), and E), gas and / or air can be forced out of the film bag before the film bag is completely closed, i.e., not sucked out. This can preferably be done by applying or exerting pressure from one side, in particular from above, across a flat and resilient or flexible area on the film bag. This can be done with a soft-elastic or resilient plate, brush, or a foam pad, or the like. Alternatively, it can be done with compressed air, which has the advantage of less wear and less risk of damage.

[0034] A so-called barrier film can advantageously be used to package an object on a carrier using a method described above. Such a barrier film can have a thickness between 10 µm and 30 µm. It can advantageously be almost a monomaterial and, for example, consist of 95% PE, whereby it can be multi-layered and consist of two thin layers of PE film. The barrier film can consist of 5% of another material, which forms a barrier layer between the two layers of PE film. This barrier layer prevents the penetration of bacteria, germs, etc. Such a barrier film has the great advantage of being very easily recycled. This also applies to the aforementioned carrier, for example, if it is made of cardboard or paper, even if it has a thin coating of wax, thin film, or the like, which makes the carrier waterproof or moisture-resistant.However, for better recycling, this should be avoided; if necessary, a separate absorbent fleece made of compostable or recyclable material can be provided on the carrier.

[0035] These and other features emerge not only from the claims but also from the description and the drawings. The individual features may be implemented individually or in combination in an embodiment of the invention and in other fields, and may represent advantageous and individually protectable embodiments for which protection is claimed here. The division of the application into individual sections and subheadings does not limit the generality of the statements made therein. Short description of the drawings

[0036] Embodiments of the invention are illustrated schematically in the drawings and explained in more detail below. The drawings show: Fig. 1a side view of a salmon fillet in a tray-shaped cardboard carrier, which are to be packed subsequently, Fig. 2the carrier with the salmon fillet made of Fig. 1 wrapped in a foil bag, Fig. 3 a top view of the foil bag from Fig. 2 , Fig. 4 a simplified representation during a packaging process for the carrier including salmon fillet from Fig. 2 , whereby air is sucked out of the not yet sealed foil bag, Fig. 5 a plan view of a foil bag closed at the edges according to Fig. 3 with a vent hole, Fig. 6 a representation similar Fig. 5 with a shrunk film bag, the vent hole being hermetically sealed by a sticker, Fig. 7 a side view of a possibility for exerting pressure on the film bag in a form-elastic manner according to Fig. 4 before the vent hole is closed, and Fig. 8 a representation of a foil bag similar Fig. 3 with a pressure relief valve on top. Detailed description of the implementation examples

[0037] In the Fig. 1 A piece of salmon fillet 11 is depicted as a food or as an object to be packaged, lying on a carrier 13. The carrier 13 is made of cardboard, possibly with a very thin coating on its upper side towards the salmon fillet 11. Alternatively, a separate layer of absorbent fleece can be provided. The carrier 13 should preferably be free of plastic and / or be recyclable. It is designed in a tray-like manner with a carrier base 14 and a circumferential carrier edge 15 bent over at the top and projecting outwards. This is also shown by a comparison with the illustration of the Fig. 3 Such carriers 13 are known in the prior art. A separate layer of absorbent fleece prevents the cardboard carrier 13 from being soaked through by the juices of the salmon fillet 11, thus remaining stable.

[0038] This bundle of salmon fillets 11 on the carrier 13 must now be packaged for sale in a foil bag. This is best done in a factory where the salmon is also cut into salmon fillets 11. Fig. 2 Such a film bag 18 is shown around the carrier 13 with the salmon fillet 11 therein, with the film bag 18 already shrunk here and thus closely adapted to the shape or contour of the carrier 13 with the salmon fillet 11 therein. Such shrinking is carried out thermally, as previously explained, advantageously by passing through a thermal shrink tunnel, whereby a film material of the film bag contracts and ensures a tight fit of the film. Another advantage of this tight fit is that the package consisting of the carrier 13 with the salmon fillet 11 therein is somewhat stabilized. The film for the film bag 18 is a special barrier film, or so-called EVOH film, as described above.

[0039] The foil bag 18 is in Fig. 3 Shown in plan view for better explanation with a transport direction T. The film bag 18 has a bottom 19, a top 20, and three circumferential side weld seams 22a, 22b, and 22c. On the fourth side 23, i.e., the left side, the film runs continuously from the bottom 19 to the top 20. The film bag 18 is thus formed with the aforementioned half-film tube and therefore only needs to be joined on three sides by means of thermal welding.

[0040] The edge welds 22a to 22c seal the film bag 18 hermetically, so that no impurities or germs can enter the film bag 18 and the salmon fillet 11. To avoid the aforementioned problems with heating of the remaining air within the closed film bag 18 during shrinking, Fig. 4During the sealing process, negative pressure is generated in the film bag 18 or air is sucked out. Fig. 4 This is illustrated in a very simplified schematic by the fact that the carrier 13 with the salmon fillet 11 thereon has already been wrapped into the half-film tube at the top and bottom, as is known from the aforementioned prior art. The front edge weld seam 22a has already been created by severing the essentially continuous half-film tube by means of a simplified cross-welding device 35. This front edge weld seam 22a extends across the entire width and seals the film bag here, connecting the bottom 19 and top 18 firmly and airtight to one another.

[0041] The right-hand edge weld seam 22b is also completely produced, specifically by means of a side welding device 37, which is also known from the prior art. Such side welding devices 37 are known, for example, from DE 199 05 888 A1 or DE 10 2006 018 083 A1. Corresponding transverse welding devices are known, for example, from DE 102011 075 532 A1. A camera 38 is arranged on the side welding device 37. This camera is part of a monitoring device with which the quality or the desired and proper production of the edge weld seam 22b on the side can be monitored. Should quality problems arise here, the corresponding packaging can be directly ejected and disposed of, or the carrier 13 contained therein, including the salmon fillet 11, can be repackaged.

[0042] On the rear side of the carrier 13 or the film bag 18 in the transport direction T, on which Fig. 3To effect the edge weld seam 22c, a suction pipe 39 is inserted from the rear into the film bag 18, which is still open in this area. Here, air is sucked out of the film bag 18, or a negative pressure is created therein. This causes the underside 19 of the film bag to adhere to the support base 14 from below and to its side walls, but above all, the upper side 20 of the film to rest on the upper side of the salmon fillet 11. Due to the usually slightly moist upper side, the film also adheres here, which has the advantage that no air can then flow in. Fig. 4It can be seen that when the film bag 18 with carrier 13 and salmon fillet 11 therein is transported along the transport direction T, the suction pipe 39 slips out of it or no longer protrudes into it and thus can no longer generate negative pressure. Air could therefore easily flow in again. For this reason, the cross-sealing device 35 is clearly close to the suction pipe 39 in the plan view. As soon as the rear carrier edge 15 is below the cross-sealing device 35 or a little further away, the cross-sealing device 35 welds the underside 19 and top side 20 of the film bag 18 and closes it. The suction pipe has been pulled out of the film bag shortly beforehand. Due to the aforementioned circumstances, this can be achieved in such a way that at least a slight negative pressure still prevails in the now closed film bag 18.The closed film bag 18 can then be heated in the usual way, which need not be illustrated here, to thermally shrink its film. This is advantageously carried out in a shrink tunnel mentioned above, as known, for example, from DE 199 20 057 A1 or US 3,777,446. Due to the negative pressure or the very small air volume within the film bag 18, no significant volume expansion can occur due to the heating, which in turn does not, or not significantly, disrupt the thermal shrinkage of the film and thus the contraction. After cooling, the film is in accordance with the . Fig. 2 and 3 a foil bag 18 which fits tightly or is shrunk tightly onto the carrier 13 with the salmon fillet 11 on it.

[0043] Since behind the foil bag 18 according to the Fig. 4If the next film bag with a carrier 13 containing a salmon fillet 11 is immediately transported, the suction pipe 39 cannot remain stationary in this position. It may have to be inserted anew each time from the rear into a partially closed film bag. Alternatively, the half-film tube can continue continuously with carriers 13 in it towards the rear carrier edge 15, where the edge weld seam 22c is placed. In this case, it may be sufficient if the suction pipe 39 extends into this half-film tube and sucks out air well in front of the cross-sealing device 35 and the side-sealing device 37, for example 1 m or 2 m. Air can flow into the half-film tube on the right-hand side, while at the front the edge weld seam 22a is always closed by the cross-sealing device 35.Despite this inflow of air, a negative pressure can be maintained in the film bag until the moment at which it is closed with the transverse sealing device 35 and thus also separated from the remaining half-film tube, which promotes air extraction.

[0044] An alternative way to avoid or compensate for the problem of volume expansion during thermal shrinkage is described in the Fig. 5 and 6 The top view of the Fig. 5 shows accordingly Fig. 2 and 3 a completely sealed foil bag 118 with a carrier 13 and salmon fillet 11 therein. The foil bag 118 is continuous on the left free side 123, as it is formed from a half-film tube as described above. It is welded at the edge welds 122a, 122b and 122c as shown in the illustration of the Fig. 4However, on a top side 120, the film bag 118 has a vent hole 125, which may have a diameter of, for example, 2 mm or 3 mm. This can be introduced in various ways. It can be created by piercing, or alternatively by thermal treatment to strengthen the edges of the vent hole 125 so that it cannot tear further as easily. Instead of being located on the top side 120, it could also be located close to one of the edge welds 122a to 122c.

[0045] The film bag 118 with carrier 13 and salmon fillet 11 therein can then be heated in a thermal shrink tunnel as described above. This shrinks the film of the film bag 118 and fits tightly against the carrier 13 including the salmon fillet 11, as described above. Heated and thus expanded air within the film bag 118 can escape through the vent hole 125 during the shrinking process. After shrinking, the film bag can then be Fig. 6 a sticker 126 is affixed to the top side 120 and over the vent hole 125. This sticker 126 can advantageously also contain information about the contents of the foil bag 118, as an alternative to its special packaging type, for example a brand name of this special packaging type. This can prevent the aforementioned contaminants or germs from entering the foil bag 118 and reaching the salmon fillet 11 through the vent hole 125. This possibility corresponds to the step E mentioned above), while the representation of the Fig. 4 corresponds to the aforementioned step C).

[0046] In the Fig. 7 A possibility is shown how a foil bag 218 can be used Fig. 5 with one in Fig. 7through a vent hole that cannot be seen, so that as much air as possible can be removed from it. For this purpose, the film bag 218 with carrier 13 and salmon fillet 11 inside can be placed on a base. A type of soft stamp 241, for example with an elastic foam base 242, is applied from above. This foam base 242 is so soft that it essentially presses air out of the film bag 218, which can escape through the vent hole. At the same time, however, it does not damage or impair the contents of the film bag 218. As an alternative to such a stamp 241, compressed air could also be blown onto it from above, and also from below, which has the same effect on the entire film bag 218 with its contents. After removing the stamp 241, the vent hole can be closed again as previously explained, for example by means of a sticker, see the Fig. 6 .

[0047] Another possibility corresponding to the above-mentioned step D) is in Fig. 8 Here, a pressure relief valve 328 is provided on the upper side 320 of a foil bag 318 with carrier 13 and salmon fillet 11 therein. It can, for example, be connected to a vent hole similar to the Fig. 5be applied, advantageously after the production of the essentially finished film bag 318 with edge weld seams 322a to 322c. Such pressure relief valves 328 are generally known from food packaging, for example from bags for coffee beans. They have a central outlet opening 329 and an invisible membrane or the like inside. If excess pressure builds up inside the film bag 318, for example during the previously described thermal shrinking of the film with volume expansion due to heating, the air can escape through the pressure relief valve 328 and the outlet opening 329. The excess pressure is therefore dissipated without any problems. In the other direction, the pressure relief valve 328 is airtight. This means that the film can contract during shrinking because the excess or contained air can escape.However, after cooling or even during the cooling process, no air can flow into the foil bag, which is also advantageous for hygiene reasons.

[0048] In a further embodiment of the invention, the carrier 13, including the salmon fillet 11 therein, can be inserted into a pre-printed film such that the imprint is located at a precisely desired and predetermined location, in particular on a top side 20. The imprint can also be such that a desired image is obtained after a precisely defined shrinkage of the film. This is known per se from the prior art and need not be explained in further detail here.

Claims

1. A method for packaging an object in a film, wherein the film is a barrier film that is thermally shrinkable and impermeable to bacteria and germs and preferably almost impermeable to atmospheric gases such as oxygen, CO2, the method comprising the following steps: A) providing a carrier and the object on the carrier, wherein the carrier projects laterally beyond the object in plan view, B) completely enveloping the carrier with the object thereon in the barrier film, C) completely sealing the barrier film around the carrier with the object thereon to form a film bag, and generating a negative pressure in the film bag such that the film bag is sealed with negative pressure therein, D) alternatively to step C), the barrier film is completely sealed around the carrier with the object thereon to form a film bag,and the finished film bag is provided with a pressure relief valve attached to the barrier film, in particular to a top side of the film bag. E) alternatively to step C) or D), the barrier film is completely sealed around the carrier with the object thereon to form a film bag, and a vent hole is created in the film bag or a vent hole is present in the film bag for venting the film bag during the thermal exposure according to step F), wherein the vent hole is hermetically sealed after shrinking the barrier film, wherein the film bag is sealed by thermally welding at least two superimposed layers of the barrier film. F) shrinking the barrier film by thermal exposure to allow the film bag to fit tightly against the carrier with the object thereon.

2. Method according to claim 1, characterized in thatthe barrier film has a thickness between 15 µm and 30 µm.

3. Method according to claim 1 or 2, characterized in that the barrier film is sealable or has two film layers made of PE with a barrier layer in between, wherein the barrier film is preferably co-extruded.

4. Method according to one of the preceding claims, characterized in that the negative pressure is created and maintained during complete closure.

5. Method according to one of the preceding claims, characterized in that the shrinking of the barrier film is carried out by thermal action using warm air, steam or in a water bath in a shrink tunnel, preferably as the film bag with the carrier and the object inside passes through.

6. Method according to one of the preceding claims, characterized in thatthe negative pressure created in step C) in the film bag after complete closure and before shrinking of the barrier film is between 0.01 bar and 0.9 bar, preferably between 0.1 bar and 0.5 bar.

7. Method according to one of the preceding claims, characterized in that the carrier with the object thereon is first introduced into the barrier film in such a way that the barrier film is below the carrier and on a first lateral side overlaps continuously and uninterruptedly upwards onto the carrier together with the object thereon, wherein on the opposite second lateral side both film layers protrude beyond the carrier and the object thereon, wherein preferably afterwards on this second lateral side the two film layers are welded to one another, in particular at a distance from the second lateral side which is less than 20% or less than 10% of the distance between the two lateral sides.

8. Method according to claim 7, characterized in that the welding takes place at least on the second lateral side in a continuous process, preferably at a constant rate.

9. Method according to claim 7, characterized in that when packing in the barrier film, the carrier with the object thereon is moved along a transport direction, wherein the two film layers are connected to one another in a transverse direction running transversely to this transport direction by welding, in particular on a front side of the carrier seen in the transport direction, wherein preferably the film bag is finally closed by welding the two film layers to one another on a back side opposite the front side.

10. Method according to one of the preceding claims, characterized in thatthe interior of the foil bag contains protective gas or dry ice, whereby the dry ice is introduced into the package and carbon dioxide is released through the outgassing of the dry ice, which completely replaces the air inside the foil bag.

11. Method according to one of the preceding claims, characterized in that the negative pressure according to step C) is generated in the film bag by introducing an elongated, inherently stable pipe into the not yet completely closed film bag and then sucking air out of the film bag through the pipe, wherein in particular the air is sucked out while the film bag is being closed, wherein preferably the pipe is pulled out of the partially closed film bag before the film bag is completely closed.

12. Method according to one of the preceding claims, characterized in thatthe negative pressure according to step C) is generated in the film bag by generating a negative pressure in a laterally closed film tube in which a plurality of objects are lined up one behind the other, wherein a welding stamp running transversely to the longitudinal direction and preferably moving with it seals and separates the first object in the film tube outside a unit generating the negative pressure, wherein in particular a suction pipe for generating the negative pressure is immovable or static in the film tube.

13. Method according to one of claims 1 to 12, characterized in that alternatively to steps C), D) and E), gas and / or air are expressed from the film bag before the film bag is completely closed, preferably by applying pressure from one side, in particular from above, to the film bag in a flat and yielding or flexible manner, preferably with a soft-elastic plate or with compressed air.

14. Use of a barrier film for packaging an object on a carrier using a method according to one of the preceding claims, wherein the barrier film preferably has a thickness between 10 µm and 40 µm and is in particular a multi-layer film.

15. Device for carrying out the method according to one of claims 1 to 13, characterized in that it has means for generating a negative pressure in the not yet completely sealed film bag, wherein the means for generating a negative pressure preferably have an elongated suction line.

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