DE19828381A1 - Packaging for food, which has a gas-tight cover - Google Patents

Abstract

Packaging for food comprises an edge flange, an inner plastic film lining, and a gas-tight plastic cover film sealed onto the edge. A shell section forms the base (41) and side walls (43), and an edge flange (52) is placed inside and forms the collar.

Description

The invention relates to a food packaging ge according to the preamble of claim 1 and a method for Production of such a packaging according to claim 13, a device for performing such a method according to the preamble of claim 19, one for this suitable semifinished product or tray in the form of erect and glued trays according to claim 23 and a method its manufacture.

Food packaging is in great variety the market, with recent special efforts be made, the proportion of non-recyclable Plastics with such packaging to a minimum limit. So far, groceries have packs in the form of deep-drawn plastic trays enforced, which is usually made of a carrier material be thermoformed, which for example made of PVC, poly esterol or polyester is formed.

The conventional ones made of PVC, polyester or poly Shell made from esterol is produced in terms of production technology due to so-called "vacuum forming and filling systems" very uneven thickness distribution due to the available standing output strength in the known thermoplastic Deformation process.

On the one hand, this requires related to the desired Drawing depth and container shape up to a strong starting thickness 1000 µm in order to achieve the required residual wall thickness in the Bo to reach the radii. On the other hand, the thinning leads the one to be used for shaping the plastic shells  Plastic films in the base radii very often too ten "kink breaks", especially during transport may occur.

Series tests have also shown that the results of the Production of the plastic shells used barrier layer layer, preferably made of polyvinyl alcohol (EVOH), which the required oxygen barrier guaranteed and at a previously described application of so-called rigid foil ver bound between the carrier film and the sealing layer is embedded, a much poorer molding result shows d. H. small residual wall thicknesses, too Has EVOH layer.

It is therefore necessary that art backing material of the shells to be formed, for the Dimensional stability is required, with an additional acid barrier layer is equipped. This oxygen barrier Layer usually consists of polyvinyl alcohol. Additional Lich a third layer of film is required to To be able to seal the lidding film.

This requires a so-called multi-component existing, relatively thick multi-layer composite film, the one Recycling, i.e. a single reuse, impossible do.

Such a shell is for example in the EP 0169799. It also contains a method of with a variety of individual, separate Trays in a filling or sealing station be performed. The shells are successively made with one thin plastic layer lined before spitting with sp filled and sent to a sealing station the. A cover film is applied in the sealing station sealed the bowls filled with food. Ent stands a bowl, the carrier material is essentially  Wood grinding or foamed plastic. The advantage of these packaging systems with such trays in that the packaging device is clear can be built, including a modular together Position of the device is possible.

In contrast, attempts have been made to reduce the plastic content such food packaging, which, in order to meet the requirements to achieve residual wall thicknesses in the base radii, must be relatively high, by reducing that coated cardboard is used. Here it has However, it was found that it is difficult to use cardboard coated plastic materials in devices too process in which largely known or already exi permanent modules are used. In addition, at such pressed from pressed cardboard containers maximum mold depths limited to 25 to 30 mm.

Even if through a barrier film lamination such containers manufactured in the cold pressing process are equipped so that they are oxygen-tight due to the cold forming process folds due to the resulting material displacement. This unfolding extend into the edge flange area of the container, making a safe and uninterrupted, but most of all oxygen-tight sealing with the cover film impossible becomes. For example, container depths of more than 30 mm To produce depth of form, containers are made of coated used cardboard, which are formed from blanks. This made of coated cardboard on a separate unit gat are erected, folded and glued and used as loading container fed to the packaging system.

However, it is not possible to use coated ones Cut the manufactured container to the cut or glue order really gas and oxygen tight to connect. Such problems occur in particular with containers  which have an edge flange. With the already known Coating of cardboard blanks is only one White moisture stability achieved, with the open Edges also do not completely remove moisture can be shielded.

However, there is a need for a grocery store Pack according to the preamble of claim 1 create that with little conversion effort on conventional horizontal form, fill and seal system is adjustable, the proportion of plastic on a mini mum is reduced, but at the same time the stability of the Container and the oxygen density on a special high level can be maintained.

Another need is a procedure for the oxygen-tight packaging of food under With the help of a food packaging of the above Kind in such a way that conventional Packaging systems with a higher cycle rate and still running can be operated more economically. After all, one is looking for a device to carry out the aforementioned method, which is characterized by a particularly low susceptibility to faults in packaging systems distinguishes itself even with the highest number of cycles.

To meet these needs, the earlier patent application P 196 54 230, on the content here express reference is made to a food ver pack as well as a process for their production and a Device for performing the method with a suitable Semi-finished product or tray proposed.

The food packaging proposed there has as load-bearing base with a thin plastic composite foil lined cardboard blank, which automatically on straightenable and ver its interior at the cut edges  sticks. The cardboard blank also has an edge flange with individual edge flange segments, on which then the lid film is attached. In addition, the Edge flange according to the invention shaped on the outside so that the Edge flange segments flush in the sealing position close. For this purpose, the individual edge flange segments miter cut lines on the basis of which the win angle position of the edge flange can be determined. By the use of prefabricated cardboard blanks results the advantage that when erecting the cardboard blanks no material thinning occurs, in contrast to the be knew bowl. This means that due to the material ver thinning disadvantages with the invention Food packaging overcome. Because the edge flange segments flush in the sealing position close, there is a closed edge flange top surface, which then securely seals the box tailored to be used.

With such, gas or oxygen tight Packaging, however, is approaching this to a special degree make sure that the one made over the sealing flanges Tightness guaranteed even over a longer period is. Otherwise, the food technology requirements can no longer be met. With the one already proposed Packaging is the quality of the seal through the Precision of the blanks determined. In other words, the danger that ambient air in the medium term Packaging over capillaries in the sealing flange can only through extremely high precision in the manufacture of the erected trays and when positioning in the Lining and sealing station to be insulated. Hereby the working speed may be unduly reduced become.

The invention is therefore based on the object Food packaging of the type described above  create that through the advantages described above and additionally characterized by the fact that they are faster and more reliable with permanent gas or Oxygen tightness can be made. Another The task is to create a process for a to provide such food packaging, according to a simple process is feasible. After all, it should a device for performing the Manufacturing processes are created that are simple is built and offers the special advantage that conventional packaging systems as much as possible can be integrated into the device. Finally should be a semi-finished packaging or a packaging tray be created, which is particularly advantageous Suitable for the packaging method according to the invention, the design should have the advantage that high Quantity per time unit with such high precision are producible that the quality requirements of a oxygen-tight packaging even with the greatest throughput of Packaging system are ensured.

This task is carried out with regard to Food packaging with the characteristics of Claim 1 solved. According to the Packaging with a continuous collar, which is therefore a continuous surface for sealing the Provides packaging. The continuous, d. H. uninterrupted collar has advantages already when attaching the lining of the inside of the packaging Plastic film, as the best conditions for one large connection between plastic film and Edge flange are formed. In addition there is the additional advantage that even with larger Packing machine one working speeds Damage to the plastic film can be excluded. The decisive advantage is shown when sealing the Packaging. Because the uninterrupted, from the  Plastic film covering the surface of the liner Edge flange offers optimal conditions for a Sealing the cover film as large as possible. It has has shown that in this way the Working speeds of the packaging machine considerably can be increased without running the risk that Capillary-like radial channels between Cover film and lining film arise, one Long-term tightness would be detrimental.

The inventive design of the Food packaging does need something more complex structure of the packaging blank. It appears however, that the circumferential flange in particular advantageously for stabilizing the packaging tray can be used even if the connection between the tray components only selectively or is carried out in areas and not over the entire area.

A particularly advantageous further development results with the further development of claim 2. Because this Design allows weight in the area of the shell part to save what's positive on the DSD fees affects.

Basically, it is possible to put on to form a continuous collar as a closed ring. With the development of claim 3, however achieved particular advantage that a lower waste arises. In other words, cardboard mass can be useful and effective to stabilize the side walls of the Shell part can be used.

If the tabs of the edge flange on the inside attached to the side walls of the shell part, preferably are glued, there is the particular advantage that the Full-surface outside of the side walls for printing,  d. H. can be used as information and advertising space can.

The packaging according to the invention is suitable in special way for a semi-finished product made of cardboard.

According to claim 6, the plastic composite film Oxygen barrier layer, preferably made of polyvinyl alcohol, a sealing layer, preferably made of peelable polyethylene, and an adhesive layer, preferably made of modified Po ethylene, especially a copolymer of ethylene with 6% Methacrylic acid, partially (50%) with Na or zinc ions are neutralized (Surlyn A), so it becomes more flexible Composite used, its oxygen permeability in the front can be set from and also in the embedded Zu was not changed. Therefore one can clearly thinner EVOH layer, which in a flexible ver is embedded, can be used. Due to the Peelability of the plastic film results in a excellent environmental compatibility. The plastic film can - as surprisingly turned out - be kept extremely thin and still the tray, even if it consists of simple cardboard, stabilize in such a way that even relatively deep packaging with sufficient great stability can be produced.

If the food packaging according to the invention Claim 9 preferably with a cardboard blank equips that of one recyclable or preferably two layered cardboard, it becomes a food packaging created that is suitable on the outer layer of the cardboard blank a special advertising effect bear pressure. This in particular becomes a possibility created the food packaging op to emphasize table.  

The design according to claim 10 has the special advantage that the surface structure of the tray is adapted to the specific requirements. For the Lining the shell, it is advantageous if the Form a heated plastic film in a short time intimate connection with the surface of the shell part comes in. In contrast, it happens for the outside of the Shell part depends on it, an appealing appearance and good Requirements for the usually to be done To create printing. It has been shown that the second, d. H. inner layer without further notice recycled cardboard can exist, reducing costs be saved and special advantages in terms of Environmental compatibility can be achieved.

The inventive choice of the lined Kar There is a container in the clay cut-outs, which is used for shrinking into the vacuuming or sealing station except for one Side, namely the upper side, is oxygen-tight. There in addition, the plastic-lined cardboard blank also in the field of those specially trained according to the invention Edge flanges can have a particularly high dimensional stability this edge flange between the seals of the closed NEN sealing tool can be safely recorded so that it according to the invention, only the inner cavity of the shaped door cup must be evacuated. The power consumption of the Packaging system for generating the evacuation is ver wrestles, the cycle number of the packaging system can be raised significantly.

It has been shown that the invention formed edge flanges a high stability is achieved and even when filling the bowl with food uncontrolled break did not occur. The Betriebsverver The device can also be non-permissible be raised by the fact that the between the carrier interiors are designed as sealing webs  Edge flanges from below using parallel to the transport screed aligned slide and guide rails become. The training is also advantageous that the Be container in the filling section from below using a support belt running synchronously with the transport device be supported.

By inventing the erected cardboard blanks according to claim 15 in rows in the forming station are arranged, it is possible that between adjacent cardboard blanks a widened sealing surface the edge flanges is formed. This ensures that the sealing is achieved safely. Furthermore, it is achieved that several cardboard blanks are made at the same time can, and through the widened sealing surface because of the adjacent edge flanges the Versie is simplified.

These further developments result in particular Advantages of largely simplifying a ver packaging system, since no separate Thermoforming stamp station or special preheating system are more needed. Nevertheless, the necessary for this The flow path according to the invention for the sub bring the filling station are used and thereby a space-saving design of such a packaging system will create.

The overall system can either be considerably shorter or the filling section can, if necessary, can be used much better, which makes the filling process is facilitated.

With the food packaging according to the invention the proportion of non-recyclable plastics Reduce minimum, with the invention  The choice of material for the cardboard blanks is an additional advantage problem-free self-rotting.

Finally, the power consumption of the packaging system, especially in the area of the forming station wrestles because the time it takes to warm a normal one Chen hard film from approx. 500 to 1000 µm (PVC, polystyrene or polyester) can be significantly reduced. The be required inherent stability of the container is inventively by using the cardboard blank he described is enough, especially if the cover film on the art fabric that lines the cardboard blank, attached is.

The food packaging according to the invention experiences ge compared to foodstuffs also using cardboard blanks tel packaging has increased dimensional stability and is in egg high degree of torsional stability.

An advantageous development of the Manufacturing process results from further training of claim 15. By tacking the Plastic film on the edge flanges of the trays the latter reliably and particularly precisely in the Packaging system can be taken over. The result is additional advantage that the filling system Module of the packaging system largely unchanged can be maintained while an upstream Module for feeding the trays particularly space-saving, namely with an overlap of one cycle feed length can be positioned in the system.

The development of the method according to claim 17 leads not only at an extremely high throughput speed, but in particular in connection with the inventive design of the shell part the advantage that the vacuum can be used extremely effectively to  the film of the lining in the shortest possible time Pull the interior of the shell part. Because the uninterrupted according to the invention, forming the edge flange Collar allows the shell part to be cut to size shape that the side walls through the erect Condition of the shell part are separated by a slot.

Advantageous embodiments of the device for The procedure is the subject of Subclaims 19 to 25. That of the invention Tray belonging to food packaging is the subject of Claims 23 to 29. The tray can be used with almost any Shaping, the special Advantages can be achieved if the shell part is a exceeds a certain minimum depth. Preferably, the Bottom a polygon shape.

With the method of making the tray according to Claim 30 manages to in the two parts of the tray in the shortest possible time and with the greatest possible accuracy join together, with the advantage that the Manufacture of the trays on the working speed of the Packaging system remains independent. The trays are preferably nested in a magazine for cardboard trays given and from there individually on a carrier belt of the Transfer module of the packaging machine given.

Objects are further advantageous refinements of the other subclaims. Below is a schematic table drawings an embodiment of the invention explained in more detail.

Show it

Figure 1 is a schematic side view of a first embodiment of the packaging system according to the invention.

Fig. 2 is an exploded view of a first embodiment of a cardboard trays for use in the manufacture of a package according to the invention;

Fig. 3 is a plan view of a carton blank for the collar of the packaging according to Fig. 2;

FIG. 4 shows a plan view of the blank according to FIG. 3 with angled tabs ready for assembly; FIG.

Fig. 5 is a plan view of the corresponding carton blank for the shell part;

FIG. 6 shows a top view of the blank according to FIG. 5 in an upright form; FIG.

Fig. 7 is a perspective view of a number of erect carton blanks;

Fig. 8 in side view on an enlarged scale the molding station of the packaging system.

Fig. 9 is a front view of the molding station shown in Fig. 8 with an inserted cardboard blank arranged in rows like a row and the Kunststoffverbundfo lie, which is supplied for the lining.

Fig. 10 is a perspective view of laterally arranged in series carton blanks that have already been lined with the composite plastic film, being shown in a direction shown in a somewhat enlarged scale cross-sectional view of FIG. 10A along the indicated by the arrow line of the row-wise carton blanks of the heat-laminated edge flange .

Fig. 11 is a front view of the vacuum or Versie gelungsstation with inserted cardboard blanks, which are already lined with plastic composite film and thus connected to a row.

Fig. 12 is a perspective view of the connected cardboard blanks with plastic composite film and sealed cover film, the details of the cardboard blank and the adhering layers are shown more clearly in Fig 12A on an enlarged scale.

FIG. 13 is a perspective view of a dung according OF INVENTION household or consumer-ready package;

FIG. 14 is a perspective view of fiction, modern dish with partially detached cover sheet;

Figure 15 is a perspective view of the bowl to the invention OF INVENTION partially detached cover sheet and partially dissolved out inner film.

Fig. 16 in a schematic representation a section of the manufacturing line of the cardboard trays;

FIG. 17 shows an exploded view corresponding to FIG. 2 of a modification of the tray; and

Fig. 18 a of FIG. 1 similar view of the packaging machine, in which the trays according to Fig be processed 17th.

In Fig. 1 is a side view of the packaging system is shown which is substantially five has main stations, namely a stitching station HS for attaching a liner sheet 134 for pre-formed trays, a forming station (FS), in which the plastic film is formed into the trays, a pouring line (BS), a sealing and vacuuming station (VS) and a preferably two-stage separating system 181 , 182, the latter also being designed in one stage.

The transport of the cardboard blanks or trays 110 arranged in a precise fit to the individual stations is preferably carried out via a transport chain 148 or, when used on a so-called "tray sealer", via a specially designed transport belt with receiving spaces for the adjacent cardboard blanks.

To stretch have relief of the transport chain 148 support belts not shown may be provided in addition below the transport chain 148th

The module labeled "I" of the actual packaging machine, which is largely designed as a commercially available machine and can only be redesigned in certain areas, is preceded by a further module II, via which the separation of the trays 110 nested in a magazine or dispenser 112 and their transfer to module I.

Specifically, the prefabricated cardboard blanks 110 - preferably in rows with 2 to 5 trays next to one another - are clock-controlled, with the aid of a preferably pneumatically operating separating device VV9, placed on a conveyor belt 112 , with which at least one of the cardboard cuts is transported clock-controlled into a transfer station US . There, the at least one tray 110 is also lift-controlled in a clock-controlled manner by means of an excavation station 114 by means of a special transport stamp 113 vertically up to the plane EKF of the plastic film 134 and into the area of the stapling station HS, in which the lining film is preferably punctually at the front by means of a heated stamp 118 - and / or trailing areas of the edge flange of the trays is tacked. In the case of a tray sealer system, the cardboard blanks are placed in corresponding receiving spaces in the transport chain 148 .

With this design, Module II is very successful space-saving arrangement and the overlap area ÜB in Saving transport direction.

Starting from this stapling station, in which the pre-fabricated trays arranged in rows and close to one another are located on the plastic film and entering the molding station FS, the actual molding or lining process of the trays 110 begins by means of the plastic, preferably the plastic composite film 134 . In the molding station, the lining of the inner surface of the cardboard trays 110 arranged one behind the other is carried out with an oxygen-blocking plastic composite film 134 .

The plastic composite film 134 is drawn from an endless roll 133 , which is fastened to a support arm above the inlet section of the packaging system, via deflection rollers (not specified in any more detail) via the trays 110 arranged in rows in the receiving molds, essentially parallel to the transport chain 148 .

When using a tray sealer, the transport chain 148 leads the trays 110 arranged in rows in the receiving spaces of the transport chain under a molding station FS, the working principle of which is to line the inner surface of the trays 110 with the plastic composite film 134 on a molding, filling - and sealing system used MULTIVAC iso-pack system.

Thereafter, the trays 110 are conveyed by means of the transport chain 148 into the area of a filling section BS, which is also designed in such a way that they permit a row-by-row filling.

To relieve the transport chain 148 which is now hanging together by the plastic composite film 134 trays 110 can by a support band that same cycle works with the transport chain, are supported.

From the filling section BS, the filled trays run into a vacuuming and sealing station VS, with a cover film 120 guided by an endless roller 122 via a deflection roller system being guided essentially parallel to the transport route into the vacuuming and sealing station VS. The operation of the vacuuming and sealing station VS corresponds to conventional systems, e.g. B. from Multivac and is described in Fig. 12 in detail.

After the filled packaging containers have been sealed, they are in turn fed to the individual stations 181 , 182 by means of the transport chain, the trays 110 which are arranged in a row in a row being supported once again by a conveyor belt 150 which operates in the same cycle.

As can also be seen in Fig. 1, the transport route of the transport chain 148 and the support belt 150 extends from the donor to immediately behind the two-stage Ver single station 181 , 182 , so that the entire system works in the same cycle.

The special feature of the packaging device is that on the one hand a specially designed tray 110 is used and on the other hand this tray 110 is manufactured in a special way and is supplied to the packaging system as a semi-finished product.

Contrary to conventional designs of such packaging systems, the dispenser 112 feeds a tray 10 which has already been formed and is dimensionally stable, for example, by adhesive bonding, with an upper edge flange 52 . The semi-finished products or trays 10 fed to the packaging device - as shown in an exploded view in FIG. 2 - have edge flanges 52 which are specially designed according to the invention and which are formed by a continuous collar which is placed on a shell part 40 .

Fig. 2 shows the two components of the tray 10 in the preformed state, immediately before the parts are assembled and connected, preferably glued. In FIGS. 3 to 5, the parts are shown in plan view in detail.

Both parts are designed as a cardboard blank, preferably a two- or multi-layer cardboard is used, so that the outside of the tray can have a different quality than the inside. The cut of the collar forming the edge flange 52 has, as shown in FIG. 3, incisions for forming trapezoidal tabs 51 which hang on the edge flange via predetermined bending lines.

The shell part 40 has a blank according to Fig. 5 and 6. At a bottom part 41 hanging over bend lines 42, the side wall portions 43 which extend in the erected state (Fig. 6 and Fig. 2) touch.

Because the angled tabs 51 are connected, preferably glued, to the side walls 43 when placed on the shell part 40 , the latter are stabilized by the edge flange 52 , so that with low use of material - low cardboard weight - a high torsional rigidity of the tray results.

The adhesive connection is preferably point-shaped or line-shaped, as indicated by the hatched areas 47 in FIG. 2.

The tabs 51 are attached to the inside of the side walls 43 so that the outside of the side walls remains continuous, which is conducive to printing.

The height H43 of the walls 43 is greater than the height H51 of the tabs 51 , ie the tabs only overlap the side walls to a fraction of the area, which saves weight and thus DSD fees.

In Fig. 7 erected, rows of cardboard blanks 10 are shown in perspective, just in case an optionally provided recessed grip GM is to be known, which can be provided on an edge segment of the edge flange 52 .

In the side view according to FIG. 8 it can be seen in which way in the forming station FS the tool halves 116 and 118 interact with the trays lying one behind the other and by means of a heating device 172 line the inside or surfaces of the trays 10 lying one behind the other with the plastic composite film 134 .

The tool of the molding station FS, which works according to the so-called skin method, consists of a lower mold 116 and an upper mold 118 , which are moved apart and moved in a clocked manner in accordance with the arrow shown in FIG. 8. Here, the lower mold 116 preferably has a pro fil for the positive reception of the cardboard blanks 10 , so that the edge flanges 52 of the cardboard blanks 10 are supported in a sealed manner. The upper mold 118 is also designed so that a heating device 172 can be accommodated. With 173 and 173 A recesses in the upper and lower part 116 , 118 are shown, which are designed according to the recessed grips GM.

In Fig. 4, the front view of the molding station FS is shown ge. It can be seen that the lower mold 116 has web-like inserts 166 , the shape of which is adapted to the cross section of the trays 10 arranged in rows. In this case, the closely spaced edge flanges of adjacent trays 10 fit precisely on these web-shaped inserts, so that when the tool halves 116 and 118 are moved together, the individual trays are additionally positively supported by the provided mold inserts 158 , the surface contours of which match the shape of the trays. The functionality of the forming station FS, in particular the skin process, is briefly described below:
If a row of erected cardboard blanks, which lie close together with their edge flanges in a row and thus form a saddle-shaped support, is introduced into the forming station FS via the attached plastic film 134 (stitching points), the lower tool part 116 of the forming station FS previously moved downward moves Up arrow direction. When moving the tool lower part 116 against the upper tool part 118, an almost complete vacuum is applied in the upper tool part 118 . The plastic composite film 134 lying over the closely spaced rows of cardboard blanks 10 is thereby applied over the entire surface of the heating plate 172 and heated.

After the specified heating time, the tool upper part 118 is ventilated with simultaneous evacuation of the lower tool part 116 . This change creates a differential pressure of approx. 1 bar, which causes full-surface heat lamination between the plastic composite film and the inside of the tray (see dashed line 134 A). Since line-shaped openings remain between the side wall sections 43 due to the design of the shell part 40 , the drawing in of the film can even be promoted.

At the same time, the continuous edge flanges 52 are heat-laminated over the entire surface.

Since the inner surfaces of the closely spaced cardboard blanks are now lined with the plastic composite films, the forming station FS is opened at the same time, which now releases the trays connected by the plastic composite film and is conveyed onwards for filling with the transport chain 148 .

FIG. 10 shows the row of trays formed by the closely spaced trays 10 and lined with plastic composite film 134 on the inside, as it leaves the molding station FS. As can also be seen, the plastic composite film 134 also covers the grip hole recess GM in the edge flange.

FIG. 10A (section along the edge flange 52 of a tray 10 with the composite film 134 lying thereon) shows the individual layers forming the composite film. The plastic composite film 134 has an oxygen barrier layer 136 , preferably made of polyvinyl alcohol (EVOH) and a sealing layer 138 , preferably made of peelable polyethylene, and an adhesive layer 137 , preferably made of modified polyethylene. It has been shown that the inner coating of the carrier material forming the food packaging can be made extremely thin. The film thickness is preferably in the range of the residual wall thicknesses in the base radii between 25 and 30 µm.

By selecting a suitable surface structure of the cardboard on the inside of the tray 10 , the interlocking of the film 134 with the cardboard can still be optimized.

The plastic composite film 134 can also be constructed and its behavior controlled so that it can be detached from the cardboard carrier after use of the packaging, so that pure components are available for disposal or recycling. According to the invention, the finger hole recess GM also serves this purpose.

After leaving the forming station FS, the trays 10 to be connected run through the filling station along the filling section BS, during which time they are filled with the foods to be packaged. The transport of the coherent trays 10 takes place at intervals, as it were, through the joint installation. The filled trays 10 run from the filling section BS into the vacuuming and sealing station VS, in which they are received by the lower part 116 by means of appropriate mold inserts (see FIG. 11). Such a vacuum or sealing station of the conventional type consists of a lower part 216 and an upper part 218 , which are moved together and moved apart in a clocked manner. The lower mold 216 preferably has a profile for completely receiving the trays 10 designed according to the invention such that the edge flanges of the shells can be supported in a sealed manner. The upper part is designed so that it can receive a heating plate having a line pattern 274 movable in the vertical direction Rich.

The line pattern is designed in such a way that it defines surface areas on which a sealing of the cardboard cut edge flange with the cover film 120 is to take place.

Fig. 12 is to the function of such a rungs- Vakuumie or show sealing tool according to the invention used. Well-known and proven conventional systems with minor changes can also be used for this process. Fig. 12 shows the sub form 216 with the web-like inserts 266 , the shape of which is adapted to a cross section of the saddle forming between two adjacent edge flanges of the trays 10 , so that in the collapsed state of the tool halves 216 and 218 the connected trays 10 through the intended mold insert 258 , the surface of which corresponds to the shape of the tray lying thereon, is positively supported. With 270 seals are marked, against which the edge flanges or the saddle webs of the connected trays 10 lie in the collapsed state of the tool 216 and 218 , so that vacuuming of the individual carton blanks, which already contain the food in this state, can be carried out .

With 274 heating devices are designated, which are accommodated accordingly a pattern aligned with the edge webs in the upper tool half 218 , so that in the collapsed state of the tool halves 216 and 218, a welding of the cover film 120 with the relevant edge flanges of the individual containers takes place such that a circumferential continuous sealing surface comes about.

Due to the special design of the continuous edge flange 52 , the seal is free of capillary channels via which a gas exchange with the surroundings could take place.

At this point it should be emphasized that a commercially available vacuuming station can be used, in which after evacuation gassing, for example with the usual gas mixture N ₂ / CO _2, usually in a ratio of 70:30, can also be used. The heating plate 274 located in the upper part of the tool 218 is preferably designed with relief-shaped sealing webs, the cover film being sealed by the action of heat and pressure with the sealing coating of the peripheral edge flange and the saddle webs of the connected trays formed thereby.

FIG. 12 shows how the trays 10 filled, sealed and connected with food have now left the vacuuming and sealing station.

As can be seen from the selected hatching, the entire plastic composite film 134 is welded to the intended sealing surfaces with the cover film 120 . Le diglich in the region of the recessed grip with GM in the rear edge flange area (seen in the direction of travel), the sealing with the plastic composite film 134 with the cover film 120 is prevented by a special configuration of the sealing tool. Using the punched hole GM provided in the rear edge flange and the cover film 120 not sealed at this point with the plastic composite film 134 , this enables the film cover to be removed later or the plastic composite film to be removed from the tray 10 .

After leaving the vacuuming and sealing station VS, the filled trays connected via the cover film and plastic composite film 134 are fed to a preferably two-stage separating system 181 , 182 .

It is also possible to use a complete punching and separation of the individual food packaging. In the case of a complete punching, the second stage of separation is therefore omitted. After leaving the singling station, the individual trays are present as shown in FIG. 13.

With the above food packaging it is possible depending on the desired shape, by on average around 20 g per food packaging save more recyclable plastic, d. H. about 70% of what occurs with conventional packaging of this type.

The working width of the device is a matter of course not limited. However, it has been shown that the widths should be at least about 420 mm to the Economy of the device on a particularly ho to maintain your level.

The cover film 120 is preferably also made of a plastic composite film 134 , which contains an oxygen barrier layer, which on the side facing the cardboard cut is covered by a peelable plastic layer, preferably made of modified polyethylene. This layer then forms the seal seams with the plastic composite film 134 via sealing webs of the edge flanges.

The film or the heating or sealing element 272 facing is preferably formed from a film quality with a particular high melting point or a heat-blocking layer, which preferably contains polyethylene and which lies over the oxygen barrier layer, in order to seal and seal with the lower part for a sufficient shape and To ensure surface stability during the sealing process. Since the gel layers of both the cardboard blank surface and the lid film 120 are preferably "peelable", a firm connection is created when these two sealing layers are sealed, which can largely be peeled off by hand without destroying the cardboard blank film 34 (see FIG. 14).

Of course, be different from the previous be written embodiments possible without the Grundge  thank to leave the invention. So it is self-evident of course, the number of feeds lined up Vary trays per row or cycle.

It is also conceivable that the tray rows after the Leaving the forming station FS via a special pre direction should be made sterile or sterile. Here it is advantageously a so-called "Hydrogen Peroxide Shower".

Due to the method according to the invention applied to both the oxygen-tight plastic composite film and the oxygen-tight cover film 120 , a composite combination of films from the polyolefin group can be used. This composite combination can be recycled as a monofilm. It has been shown that this regranulate can be used as filling material in the field of PE heavy film production.

Due to the internal coating made by means of the plastic composite film, the stability of the tray is considerably improved, particularly via the edge flanges designed according to the invention. After solidification, the plastic composite film 134 loses considerable flexibility and additionally stiffens the entire tray over the edge flanges.

Through the subsequent sealing with the cover film The carton is sealed over the peripheral edge flanges cut an additional torsional stiffness or Dimensional stability.

An extremely secure seal with those with a barrier laminated film-lined trays through the Barrier cover film is ge according to the invention create that the circumferential edge flange due to the process close together, so-called saddle bars with egg  form a sealing surface, which is increased to a double than with conventional edge flanges.

Since the entire available sealing surface, which is heat-laminated with the sealing side of the barrier plastic composite film 134 , is available as a sealing surface with the cover film 120, the individualizing of the packs only after sealing has ensured that there is always a sufficiently wide area to form a secure sealing seam maintained.

With individually fed trays, which do not have this particular design of the edge flange according to the invention, a uniformly wide and thus sufficient secure sealing surface cannot be achieved due to tolerances when fixing the trays in the process or due to the manufacturing-related fluctuations in the carton blank design. The separation of the oxygen-tight film inner component from the actual stabilizing cardboard blank is a further essential point of the invention (see FIG. 14). The plastic composite film lining the inside of the tray is heat-bonded to the fibers of the inner walls and the bottom of the cardboard blank.

By known methods, for example the Multivac Skin system, in which the heated, thus made plastic Plastic composite film with the specially trained Ka Schierschicht, which is preferably a Surlyn blend of Dupont company or a mixture (PE type) with particularly high hem (preferably over 20%) ent ethylene vinyl acetate holds, the plasticized composite film is through the corresponding pressure difference on the inside of the tray pressed and can into the fibers of this inner surface penetration.  

The cover film 120 is firmly connected to the lower part of the packs after evacuation or gassing in the sealing station via the circumferential edge flanges and the saddle webs of the row-shaped connected trays, which are coated with a sealing layer as described in the method.

The intended semi-oval punching (GM) of the rear edge flange lying in the transport direction and the ent speaking design of the sealing tool in this loading rich creates the possibility of a so-called Griffla cushions that are not covered with liner at this point sealed lidding film is formed on the intended Grip hole trough GM the entire composite from the then pure To remove the cardboard blank, which contains the pure composite is stable.

It belongs to the field of application of food packaging also peeling off the cover film from the sealing bars to Open the package to its contents easily and without any work to be able to remove stuff. This can be done through a special Design of the sealing tool in the sealing station oh a major changeover.

In this case, the consumer removes the cover film from the sealing surfaces until he can easily remove the contents (see Fig. 15). The plastic composite film and the not completely peeled-off cover film are then detached from the actual cardboard blank on the grip hole recess provided for this purpose via the grip tab. This ensures that the separation is sorted and that the individual materials can be recycled.

In Fig. 16 is a schematic view of a tool shown for the production of the trays 10th The cardboard blank 40 is erected in a bottom mold 316 and stabilized with a precise fit by means of an air suction device 319 . Aligned above the bottom shape is the upper shape 318 , which carries the erected collar with edge flange 52 .

The molds 316 , 318 are moved together after a cold or hot glue has been applied to one of the overlapping surfaces of side walls and / or tabs. If hot glue is used, the setting time can be controlled more precisely and the cycle frequency during production can be increased further. In Fig. 16 are the areas on which the adhesive is applied, indicated differently shaped, which is intended to express that there is a range of variation in the design, depending on the requirements profile of the trays.

Of course, deviations from the variants shown are possible without departing from the basic idea of the invention. FIG. 17 is a slightly modified design shows the tray. The collar 452 is designed without tabs and is placed exactly over the angled edge flange segments 444 of the side walls 443 of the shell part 440 and is thus firmly connected, preferably glued. "X" denotes those areas where adjacent wall segments 443 are connected to one another by overlapping tabs 443 A.

With this tray, a modification of the packaging system according to FIG. 18 can be useful. Erected or prefabricated trays 510 are removed from a magazine 512 in rows and transferred to a clocked conveyor belt 511 . The trays 510 are then transported under a stamping device with a stamp 517 , in which the edge flange formed by the segments 444 is broken before the collar 452 is put on in the gluing station KS, in such a way that the surface which is as flat as possible for the fitting of the collar arises with sections 444 which are as flush as possible. The stamp 517 is designed in such a way that the edge flange 552 is broken into the sealing position which is possible depending on the fermentation cut at the ends of the edge flange segments 444 with a corresponding inclination. The transfer station US (see FIG. 1) is connected to the gluing station.

If a method according to the known tray sealer is used, the transport chain 148 then transports the trays 10, which are closely arranged one after the other, in a clock-controlled manner into the forming station FS. The molding station FS can be designed in the same way as, for example, a station of a molding, filling and closing system according to the Multivac CD6000 which works according to the skin system.

The invention thus creates food packaging in the form of a stable cardboard blank with one peripheral peripheral flange on the top, according to the invention is continuous and is placed on the shell part. The Sealing surface along the flange gets this way a special quality that is watertight in the long run guaranteed.

The carrier shell consists of cardboard and carries in on the lower side in the area of the rim flanges Fold an oxygen-saving plastic film to the Sealing with the cover film is suitable.

A method, a device, is also described device for the production of an oxygen-tight food packaging, whereby preformed and dimensionally stable trays from a dispenser system or in the case of a Use via a so-called tray sealer, d. H. from Dispensers form the transport chain directly into the receptacle of a tray sealer can be used. These trays are made in a molding station with a plastic composite film, the  preferably contains an oxygen barrier layer dresses.

Claims (32)

1. Food packaging with a peripheral edge flange, which is lined on the inside with a plastic film, in particular a plastic composite film, which grips the edge flange and whose interior is sealed or sealed gas-tight, in particular oxygen-tight, via the edge flange, characterized by a the packaging base ( 41 ) and the side walls ( 43 ; 443 ) at least partially forming shell part ( 40 ) and an uninterrupted collar placed thereon, forming the edge flange ( 52 ). 2. Food packaging according to claim 1, characterized in that the edge flange ( 52 ) stabilizes the side walls ( 43 ). 3. Food packaging according to claim 2, characterized in that the edge flange has tabs ( 51 ) which are attached to the side walls ( 43 ) of the shell part ( 40 ). 4. Food packaging according to claim 3, characterized in that the tabs ( 51 ) on the inside of the side walls ( 43 ) are attached. 5. Food packaging according to one of claims 1 to 4, characterized in that the shell part ( 40 ) and / or the collar ( 52 ) is formed by a cardboard blank. 6. Food packaging according to one of claims 1 to 5, characterized in that the plastic composite film ( 134 ) an oxygen barrier layer ( 136 ) preferably made of polyvinyl alcohol and a sealing layer ( 138 ) preferably made of peelable polyethylene and an adhesive layer ( 137 ), preferably from a modified polyethylene, in particular a copolymer of ethylene with 6% methacrylic acid, which is partially (50%) neutralized with Na or zinc ions (Surlyn A). 7. Food packaging according to one of claims 1 to 6, characterized in that the cover film ( 120 ) is formed by a plastic composite film ( 134 ) which on the tray ( 10 ) facing a preferably peelable plastic layer, preferably made of polyethylene and overlying at least one oxygen barrier layer, preferably made of polyvinyl alcohol and a covering heat barrier layer, for example made of polypropylene. 8. Food packaging according to one of claims 1 to 7, characterized in that the plastic film depending an initial thickness in the range between 100 and 150 µm. 9. Food packaging according to one of claims 1 to 8, characterized in that the shell part ( 40 ) and / or the collar ( 52 ) consists of a recyclable, preferably multi-layer cardboard. 10. Food packaging according to one of claims 1 to 9, characterized in that the carton is one of the With the outer layer facing the packaging a first surface structure that z. B. as Suitable information carrier layer, and an inside second layer with a specific Has surface structure.   11. A food pack according to claim 10, characterized characterizes that the second layer preferably recycled cardboard. 12. Food pack according to one of claims 3 to 11, characterized in that the tabs ( 51 ) are glued to the side walls ( 43 ). 13. Process for gas-tight or oxygen-tight packaging of food in a food packaging one of claims 1 to 12, wherein the from Tray part and edge flange of existing trays in cycles a molding station (FS) and a filling section (BS) go through one of the vacuuming and sealing station (VS) is connected downstream, the trays () be arranged in rows in the forming station (FS). 14. The method according to claim 13, characterized in that the trays ( 10 ) of the molding station (FS) are supplied in the prefabricated state. 15. The method according to claim 13 or 14, characterized in that the lining of the inner surface of the carrier shells is preferably carried out in rows and by means of a covering the entire sealing surface of the edge flanges ( 52 ) plastic composite film ( 134 ), which is arranged in a transfer station upstream of the molding station (FS) (ÜS) is attached to the edge flanges () of the trays () (attachment points). 16. The method according to claim 15, characterized in that the transport of the trays ( 10 ) through the subsequent stations takes place by means of the plastic film forming the lining ( 134 ) which is gripped by grippers of a transport device, preferably a transport chain ( 148 ). 17. The method according to any one of claims 13 to 16, characterized in that the plastic composite film ( 134 ) is optionally formed after heating by producing a pressure difference in the trays ( 10 ) and firmly with the relevant flange and the inside of the associated trays ( 10 ) is heat-laminated. 18. The method according to any one of claims 13 to 17, characterized in that through the lining plastic composite film ( 134 ) coherent carrier shells in the vacuuming and sealing station (VS) with a cover film ( 120 ) are preferably continuously welded over the rim flange. 19. Device for performing the method according to one of claims 13 to 18, characterized in that the molding station (FS), the filling section (BS) and the sealing station (VS) are combined to form a first module (I), the one a second Module (II) forming supply unit for the prefabricated trays ( 10 ) is connected upstream, the two modules (I and II) overlapping in the transport direction of the trays ( 10 ). 20. The apparatus according to claim 19, characterized in that the first module (I) has a stapling station (HS) upstream of the forming station (), below which is a transfer station (ÜS) for the trays ( 10 ) of the second module (II). 21. The apparatus according to 20, characterized in that the transfer station (ÜS) has a vertically movable lifting device supporting the edge flanges () and the stitching station (HS) has stitching bodies ( 118 ) which can be moved vertically in opposite directions, with which the lining (11) running therebetween ) forming plastic film ( 134 ) is attached to the edge flanges ( 52 ). 22. The apparatus according to claim 21, characterized in that the stitching body ( 118 ) are heatable. 23. Tray for a packaging according to one of claims 1 to 17, characterized by a shell part ( 40 ) at least partially forming the packaging base and the side walls and an uninterrupted collar () placed thereon and forming the edge flange ( 52 ). 24. Tray according to claim 23, characterized in that the edge flange ( 52 ) stabilizes the side walls ( 43 ). 25. Tray according to claim 24, characterized in that the edge flange has tabs ( 51 ) which are attached to the side walls ( 43 ) of the shell part ( 40 ). 26. Tray according to claim 25, characterized in that the tabs ( 51 ) on the inside () of the side walls ( 43 ) are attached. 27. Tray according to one of claims 23 to 26, characterized in that the shell part ( 40 ) is a cardboard blank. 28. Tray according to one of claims 23 to 27, characterized in that the side walls ( 43 ) taper downwards. 29. Tray according to one of claims 23 to 29, characterized in that the bottom ( 41 ) has a polygonal shape. 30. A method for producing a tray according to any one of claims 23 to 29, characterized in that the blank of the shell part is first erected in a first shape ( 315 ), and that the collar ( 52 ) is then positioned precisely by means of a second shape ( 318 ) placed on the shell part ( 40 ) and connected to it via selected areas, preferably glued. 31. The method according to claim 30, characterized in that the connection is made using a cold adhesive. 32. The method according to claim 30, characterized in that the gluing is done with a hot glue.