Packaging for food, and method for its manufacture.

The invention relates to a package for foods according to the preamble of claim 1 and 13, as well as a method for producing the package according to the preamble of claim 19th

It is known, in a pack, the pack or the like from an outside of a rigid material, such as cardboard, paperboard., Is to provide an inner packing which is completely enclosed by the outer package. This package has the advantage that the inner package can be hermetically sealed, which is necessary for maintaining the freshness and flavor of the packaged goods. To optimize the use of materials it is therefore gone over the overpack pretty stiff material and the inner package of a soft viscoelastic material such as film, produce, so that the inner package has an extremely low vapor permeability.

The inner pack is formed so that a goods carrier is provided, which is closed at the top by a film, wherein both heat-sealing and bonding the foil to the product carrier has been applied.

This type of internal packaging but difficulties arise when the film to be printed quickly, to quickly get to the goods. Firstly, an aroma-tight seal must be achieved in the composite body, otherwise the aroma would escape einzusiegelnde here. Secondly, this joint must be long-term stabilized, since the shelf life of the goods to be stored can optionally be months.

Thirdly, the joint must be equal to mechanical stresses. It has been shown that, etc. in the usual rather rough handling of chocolates packs. the seam can burst despite using an overpack, if the inner package is glued to the outer pack down and the outer package is greatly deformed to press the department on the film.

For this reason, a package with inner packing and outer packing is known, wherein the inner package comprises a heat-sealed foil.

In order to allow a secure fastening of the film to the goods carrier, which is provided for heat sealing the edge of the product carrier is several millimeters wide.

In contrast, it is for the earth's dung to create a package, in which a low-cost and simple production is possible, but the pack aroma tight is long-term and can be sealed the package easy and aesthetically pleasing tearing.

This object is achieved by claim. 1 Advantageous further developments result from the further claims.

By forming the flange parallel to the closing film and above this, the inner pack can just bear with their seam on the outer package. Thereby, even when the product presses against the sealing foil during transport, an increased counter pressure of the outer pack applied to the seam, so that the Aufreißgefahr is reduced. Already hereby conditionally can be comparatively weakly developed the seam. Surprisingly therefore the impact resistance of the package is greater than with all-over design of the overpack.

The closing film can also be designed visually appealing, with the package mirror presents the viewer.

By moving the connecting seam between the foil closure and the product carrier to the inside, several advantages are achieved. First, the breaking load of the joint is increased in compression and distortion of the pack. The shear stress of the seam at damaging the outer package is lower, because the introduced force is better distributed through the outwardly extending connection seam free edge of the article carrier.

Further, the sealing film to open the package can be easily and residue-free, ie without stuck foil scraps, pull. The closing film is stabilized by their connection free edge so that it is less prone to breaking from the outset. Further, the pulling direction is deflected, that is introduced as a shearing force even during rapid tearing of the pack most of the time spent tearing as tension in the seam, but not in the sealing foil. This is achieved in that the closure film forces are deflected when tearing through the above the connecting seam extending edge of the outer package and the sealing foil is supported with the torn and the folded portion at the inner surface of the edge of the outer package.

In addition, the free edge of the closure overlying film also acts as a resilient support between the edge of the product carrier and the flange of the outer package.

Particularly favorable for the invention effect to be achieved, if the seam inside the free edge of the flange of the outer package is arranged since then pretty much foil material is not available outside of the seam.

The closure sheet can be handled outside of the seam at an edge of the package, at least partially, and it is particularly advantageous if a piece of folded-over sheet is used as a pull tab. This may be covered in the closed state of the flange part, however, so that a sufficient grip length is available. To facilitate the touch and to prevent the tearing of the closure film to tab portion, the tab has in the region of the connecting seam the width of the sealing foil and running to conically from its free end.

It if for achieving one hand aroma-tight, on the other hand easily openable package a heat sealable film for the goods carrier is used is particularly favorable. This - to be distinguished from the closing film - film is advantageously designed as a composite film which is thermoformed according to the invention. Surprisingly can be personalized with the inventive method, product carriers by thermoforming produced at such a depth that they or the like for even for products ,, as chocolate or confectionery individual items, chocolates. sufficient. A drawing depth of 18 mm can be achieved. For this purpose, a composite film with aluminum core is plastic laminated or coated on both sides.

It is favorable to use a heat-sealable plastic film, such as rigid PVC, as the upper inner layer of the article carrier.

When using a composite film according to claim 7, the polyamide layer is conveniently thinner than the aluminum layer and the aluminum layer is formed thinner than the PVC layer.

Conveniently, the edge inventive construction on two opposite sides, particularly on the long sides, the package is provided, and one of the two largest surfaces of the cuboid, prismatic, full- or half-cylindrical shaped pack basic form is covered by the closing film. A tear device is integral with the closure film, in particular in the form of the sealing foil lengthening flap, formed on a narrow side of the pack.

The seam may consist of a gas-tight adhesive or weld. Furthermore, the product carrier has at least one sorting tray for chocolates, where necessary, a web is provided which divides the goods carrier, the web is up considerably narrower than the peripheral edge of the article carrier.

Here, the end portions of the webs in radii are best auslaufend formed which diverge seen from the jetty so that two shell-shaped recesses are formed by a web and web-radius of the deep-drawn wall is formed in the drawing direction extending pleats in the transition region.

Deep drawing can be carried out advantageously with a known thermoforming mold, where points are advanced relatively low pulling stress of the film and are particularly exposed to spacers that reduce the presser foot pressure in places large bending stress.

Advantageously, prior to thermoforming a lubricant, in particular isopropanol, applied to the top layer.

According to an advantageous embodiment, the size of the radii is determined in the side walls of the product carrier by reduced for a given composite sheet, the radii and / or the sidewall height is increased to adapt to the radii of longitudinal folds in thermoforming direction.

Further details, features and advantages of several embodiments of the invention are explained in detail in the following description. Show it:<ul><li>1 is a perspective view of an embodiment of the package according to the invention, wherein the outer pack is shown with opened lid;</li><li>2 shows the pack according to FIG. 1 in cross section without lid,</li><li>3 shows a schematic side view of another embodiment of a product carrier according to the invention; and</li><li>4 is a plan view of the embodiment of the article carrier in accordance with Fig.3.</li></ul>

The package 10 shown in FIG. 1 has an outer package 12 and an inner pack 14th The outer package consists of cardboard or a similar stiff material. The inner pack is composed of a sealing film 16 and a product carrier 18, as is apparent from FIG. 2. The product carrier 18 is also composed of a foil as it is explained in detail below.

In the embodiment shown in FIG. 1, the outer package 12 a hinged lid 20 which is hinged in a known per se at an upper longitudinal edge by forming a Scharnierfalzes and integrally formed on the outer package 12.

The overpack 12 is erected in the preparation of a package blank. The finished inner pack 14 is not shown pivoting walls - either at the bottom side or on the front sides of the outer package - introduced, wherein the closure means of the known plug-in tabs is carried out, so that the outer packing 12 has a of a cardboard box corresponding having in its box-like configuration.

According to the invention 12, a flange 22 is at the top of the outer pack is provided, which extends at least along the upper longitudinal edges of the outer pack 12 and in the illustrated embodiment is formed circumferentially. The flange 22 has along the longitudinal edges on a constant width of, for example, about one tenth of the package width. Along the upper end edges of the outer package 12 of the flange 22 is tapered toward the figure axis.

The closing film 16 has a tear device to a folded flap 24, which serves to rupture the package or to pull off the sealing film 16 of the product carrier eighteenth The flap 24 tapers toward the packing center and lies flat on the sealing foil 16th

When tearing the package 10, the tab 24 is now pulled obliquely upwards-left in the representation of FIG. 1. Tearing of a seam 26 shown in Fig. 2 between the goods carrier 1 8 and the closing film 16 begins at the narrow point 28 of the flange 22 approximately in the center of the upper end-side edge of the article carrier 18. The starting gradually increasing from the narrow point 28 width of the flange 22 allows for a smooth transition of the resistance that the connecting seam 26 due to the force application angle entgegengestzt opening, up in the corner regions 30 and 32 inside. In the corner areas 30 and 32 of the flange 22 is rounded with a small radius, so that the decrease in the strength does not take place abruptly.

Since peel off the sealing film 16 of the product carrier 18 along the longitudinal sides of the connecting seam 26 is acted upon by a combination of shear and transverse forces, a smooth mounting is possible. Surprisingly, the impingement of the joint 26 is suitable to shear forces during tearing open the pack to reduce the risk of cracks in the sealing foil sixteenth

That the application of shear forces is favorable here is so surprising because the connecting seams shear forces usually larger resistances oppose the transverse forces in the best for the tearing direction.

According to the invention, the film is stabilized, characterized in that outside of the connection seam 26, a peripheral free edge of the film 34 is formed, as can be seen from FIG. 2.

The free sealing foil edge 34 slides during the tearing of the package 10 between a also apparent in Fig. 2 free edge 36 of the product carrier 18 and the flange 22 inwardly laterally and so at the same time forms a guide for the below-open areas of the closing film. In addition, the sealing film 16 is folded in rupture of the package 10, so that the flange 22 - also due to the applied forces - is slightly pushed up and pull out the sealing foil edge 34 is facilitated.

The narrow portion 28 is opposite - also for aesthetic reasons - a further narrow point 38 provided in the flange 22nd

In addition, the provision of the narrow point further provides the possibility of 38, the strap 24, if desired, also be provided at the narrow point 38, to which it is particularly suitable for right-handers.

Optionally, each may be provided at the narrow locations 28 and 38 and two flaps.

From Fig. 2, the design of the inner pack 14 is seen in detail. The sealing foil 16 is connected via a circumferential connecting seam 26 sealingly connected to the goods carrier eighteenth The joining seam is made in accordance with an advantageous embodiment, by heat sealing, wherein the product carrier 18 consists of a sealing foil, the heat sealing allowed. Within the product carrier 18 insets are provided for chocolates on two levels. The product carrier 18 has side walls 40 and 42, the slightly tapered downwards - converge - at an angle of 10 degrees. In this way, the stability of the package is increased on the one hand, on the other hand the removal is facilitated. Furthermore, the product carrier 18 has rounded corners on all sides, that is, both in the corner regions 30 and 32, as well as to its bottom wall 44 toward, at, to reduce the risk of injury to the user.

It can be seen that the foil edge 34 is located between the flange 22 and the free edge 36 of the product carrier 18 and thus seen from the package center is located outside of the seam 26th As a sealing film 16, any commercially available composite or aluminum foil is concerned, which allows heat sealing of the seam 26 and is also get printable.

Particularly low as closing film 16 is a laminated plastic laminated aluminum foil from a 30 μ thick aluminum layer and a 40 μ thick polypropylene layer, instead of polypropylene and a polyethylene layer can be used. This film has a very high tensile strength in the longitudinal direction, which is favorable for the present application, and it is readily possible to print them. A coloring of the film from below, which is desirable in view of the folded pull-tab can be performed by pigmentation of the adhesive layer between the plastic and the aluminum layer. The heat sealing or optionally the bond is between the plastic layer and the product carrier.

The further embodiment shown in FIG. 3 has an article carrier 18 with two ridges 48 and 50 which extend over the entire height of the goods carrier and extending in the transverse direction of the package, as is also evident from Fig. 4.

The webs 48 and 50, the inner pack is divided into three bowl-shaped individual containers 52, 54 and 56, which are covered by a common foil seal sixteenth

The connecting seam 26 extends also through the webs 48 and 50 so that the individual containers 52, 54 and 56 are sealed from each other. On the webs 48 and 50, however, the joining seam is for example only 1.5 mm wide, while it is formed circumferentially 4 mm wide. In addition, the adhesion of the seam to the webs 48 and 50 is reduced so far that a break of the film is 16 excluded on the webs 48 and 50 by respective production technical measures.

This measure is necessary because 48 and 50 upon opening of the inner pack there is no support to a flange 22 of the outer package on the webs.

The formation of the joint on the webs 48 and 50 allows the individual containers 52, 54 and 56 to break each separately and keep sealed aroma-tight depending still sealed individual containers.

In this embodiment, the steepness of the side walls 42 and 40 is slightly less than in the embodiment according to Fig. 2, so that the angle relative to the vertical is 15 °. The web walls of the webs 48 and 50 each have the same slope. Further, the radii of the corner regions 32 and 30 and at the opposite corner regions are enlarged. In this case, the individual containers 52, 534 and 56 are each constructed symmetrically, so that the same radii at the end regions 58, 60, 62, 64 of the webs 48 and 50 occur, as is apparent from Fig. 4.

According to the article carrier 18 is constructed from deep-drawn composite film in this embodiment. The composite film of the invention has an aluminum core, which is surrounded by plastic layers that are applied by a conventional method adherent to the aluminum foil.

In the present embodiment, the following layer structure is provided:

An upper inner layer 66 consists of 60 μ rigid polyvinyl chloride. A core layer 68 consists of 45 μ aluminum. A lower outer layer 70 consists of 25 μ polyamide. Surprisingly this composite film can be drawn at a depth sufficient for chocolates, namely about 18 mm without breakage occurs. The flow properties of polyvinyl chloride contribute to channel occurring in the core layer 68 and voltages to equalize so that the composite sheet 72, consisting of the specified layer structure, does not tear during thermoforming.

The inventive method for this purpose is especially designed and is described in the following.

It is built from a conventional thermoforming mold punch and die, wherein the die of the male part is surrounded by a holding-down device which acts on a pull ring. Redraw ring and clamp on the edge 36 of the composite film 72 is formed.

The distance between the inside diameter of the drawing ring and the outside diameter of the punch is in this case more than one material thickness of the composite film, in order to allow free formation of the side walls 40 and 42nd According to the invention it is provided to use spacers between the blank holder and the drawing ring, which are incorporated between the free edge 36 and the hold-down and have a thickness of about 1 mm. The spacers extend along the entire free edge 36, ie circumferentially about the goods carrier 18th

The effect of the spacers lies in the fact that the hold-down pressure is reduced. In particular in the region of the webs 48 and 50 so the flow of material is more easily possible, so that a deep-drawing in the specified order is possible.

According to the invention it is possible in this case that barely perceptible longitudinal folds in the material flow forming at the edge 36, while 48 and 50 are provided on the radii of the end 58, 60, 62 and 64 of webs likewise longitudinal folds. it, if this area is acted upon by relatively small holder pressure, so that there the flow of material can be carried out in the best way, is particularly favorable.

There resulting small creases do not interfere with the appealing Gsamteindruck the inner pack, however, contribute to the stabilization. The maximum potential for current production ratio is achieved when the pleats are folded over a maximum as far as it corresponds to the simple material thickness.

In an inventively experiment conducted in isopropanol was used as a lubricant was applied to the upper inner layer 66th Due to the comparatively thin design of plastic layers surrounding the core layer 68, the aluminum nature of the product carrier 18 is not impaired.

As part of a comparative experiment was tried, the composite film in reverse direction, that is, with lower side PVC layer, deep draw. Here, however, cracking was already at a drawing depth of 12 mm.