DE102008037214A1 - Method for producing a packaging material - Google Patents

Abstract

The invention relates to a method for producing a packaging material (1), comprising the steps of providing a flexible carrier material (2), applying a metal-containing diffusion barrier layer (3) to the carrier material (2), and applying a protective layer (4) to the diffusion barrier layer (3 ), and a layer material based on a biologically decomposable carrier material (2), in particular for packaging purposes, comprising a metal-containing diffusion barrier layer (3) arranged on the carrier material (2), and a protective layer (4) arranged on the metal-containing diffusion barrier layer (3). A method for producing a packaging material and a layer material based on a fiber-containing carrier material, which can be produced inexpensively and in a simple manner, is created by applying the diffusion barrier layer (3) to the carrier material (2) by means of a vapor deposition method.

Description

The The invention relates to a method for producing a packaging material according to the preamble of claim 1 and a layer material Basis of a fibrous carrier material according to the preamble of claim 13.

Out In practice, a variety of different packaging materials known, in particular for storing liquid-containing substances are suitable. In addition to known cans and canisters made of metals as well as bottles made of plastic or glass it is especially for the packaging of liquid foods known, folded packaging made from a sheet material use. A known layer material of such packaging comprises while a flexible carrier material of a pulp, for example Paper or board on which a diffusion barrier in the form a glued aluminum foil is applied. On the diffusion barrier layer Furthermore, a protective layer is applied, which consists of a plastic, in particular polyethylene, and which is a liquid density Surface forms. The task of between the carrier layer and the protective layer disposed diffusion barrier layer is, molecules to prevent diffusion through the packaging material. Next leakage of molecules from inside the package In particular, it will also allow the penetration of molecules from the outside into the interior of the packaging, which prevents effective even for a long time Storage impurities or changes in taste can be safely avoided. Important here is in particular a good barrier effect of the diffusion barrier layer opposite Oxygen molecules, to prevent premature oxidation of food to avoid.

EP 1 285 744 B1 describes a method for producing a multi-layer packaging material comprising a diffusion barrier layer of aluminum foil. To produce the packaging material, the aluminum foil present in long strips is first coated on one side with a reducing agent, for example vitamin E. Thereafter, the aluminum foil is wound into a roll so that both sides of the foil come into contact with the reducing agent. For the formation of the packaging material, the aluminum foil is then unwound from the roll and glued on a first side by means of a polyolefin resin with a fibrous carrier material, which may for example consist of cardboard. At the same time, another polyolefin layer, which serves as a protective layer, is applied to the aluminum foil on the opposite second side. Furthermore, it can be provided that further layers, for example in the form of printing ink or further plastic layers, are applied. A disadvantage of this method is that the aluminum foil can easily be damaged during the production of the packaging material, which limits its function as a diffusion barrier layer. Pretreating the aluminum foil and rolling it up on a roll are labor intensive and therefore costly. Another disadvantage is that the aluminum foil must have a relatively large thickness in the range of a few micrometers in order to be able to withstand the stresses during the production process. This leads to a relatively thick diffusion barrier layer and a high material consumption, since the functionality of a diffusion barrier layer can already be achieved with a much thinner aluminum layer. Finally, it is disadvantageous that the aluminum foil is connected to the carrier material by means of heat-sensitive polyolefins, so that the risk of detachment of the aluminum foil from the carrier material under the action of heat exists. In the process of bonding undesirable wrinkles of the aluminum foil can occur, which reduce product quality.

DE 195 02 103 B4 describes a method for producing packaging in which a gas comprising silicon is introduced into a plastic packaging, for example a plastic bottle, in order to vaporize a barrier layer of a silicon compound on the inside of the packaging. A disadvantage of this method is that a uniform coating, for example, at corners or edges of the package can be achieved only with difficulty by different geometries of the packaging. A further disadvantage is that a protective layer can not be applied to the thus created diffusion barrier layer without complicated further process steps. Without such a protective layer, however, the thin diffusion barrier layer can easily be damaged.

It The object of the invention is a process for producing a Packaging material and a layer material based on a fibrous Specify carrier material, the cost-effective and can be easily produced.

These Task is for the method mentioned in the invention by the characterizing features of claim 1 and for the The aforementioned layer material according to the invention by the characterizing features of claim 13 solved.

The method according to the invention for producing a packaging material comprises the steps of providing a flexible carrier material, applying a metal-containing diffusion barrier layer on the carrier material and applying a protective layer on the diffusion barrier layer, wherein the application of the diffusion barrier layer is carried out on the carrier material by means of a vapor deposition method. By using a vapor deposition method for applying the diffusion barrier layer to the flexible carrier material, it is advantageously possible to securely apply a particularly thin diffusion barrier layer to the carrier material, without the risk of damage being caused by mechanical stresses on the diffusion barrier layer material. Another advantage is that the diffusion barrier layer is applied directly and without the provision of a further network layer, such as an adhesive layer, on the substrate, resulting in a particularly intimate, material connection between the diffusion barrier layer and the substrate.

By the relatively thin formation of the diffusion barrier layer the process still needs only a relatively small amount Amount of barrier material, which is a significant cost reduction means and continues to have the advantage of better recyclability of the packaging material. When using a roll present carrier material, for example a cardboard or a paper, can with the invention Process continues the production time of the packaging material be reduced, since immediately after a vapor deposition of the substrate a protective layer may be applied to the diffusion barrier layer can. It is also possible immediately after vapor deposition additional layers, for example a reducing agent, to which Apply diffusion barrier.

Preferably is the sputtering process selected from the group comprising physical vapor deposition, in particular sputtering and / or thermal evaporation processes, and chemical vapor deposition. By means of said methods, it is cheap and safe possible also large areas of the flexible carrier material to vaporize completely. Furthermore, it is easy possible, the steaming step even with existing To use plants for the production of packaging materials, since for a steaming system for a procedure the group mentioned only relatively little space is needed.

expedient For example, the metal-containing diffusion barrier layer comprises aluminum. Especially the barrier material can be made of pure aluminum, a Alumina, another aluminum compound, an aluminum alloy or a combination of these materials, with pure Aluminum or alumina is preferred as the barrier material becomes. Aluminum offers the advantage of being good for use to be suitable for food packaging because it is non-toxic and forms a good diffusion barrier to oxygen. Furthermore, aluminum offers the advantage of a very high opacity, what a shelf life of stored in the packaging food further increased. It is understood that in addition to aluminum also more Materials used to form the diffusion barrier layer especially other metals such as gold or platinum. These offer at higher costs for the starting material also provides excellent protection of the materials surrounding the packaging material.

Preferably the thickness of the diffusion barrier layer is less than 5 microns, the thickness more preferably even less than 1 micron. Such, compared to a conventional aluminum foil significantly smaller thickness the diffusion barrier layer is already sufficient to provide excellent Barrier effect against penetrating molecules and also to achieve light. At the same time means the formation of a barrier layer with such small thickness a considerable Material savings compared to conventional packaging materials, which in addition to a cost reduction also to a better recyclability the packaging material with conventional recycling methods leads.

Suitably, the application of the protective layer to the diffusion barrier layer by means of an adhesive method. In particular, when the diffusion barrier layer is made of a polymeric material, the protective layer can also be applied directly to the diffusion barrier layer, for example by application or spraying. Preferably, the protective layer material is a polymeric material, for example polyethylene or polylactide. Alternatively, however, this may also be a fibrous material, for example cardboard, or a mixture of a fibrous material and a polymer material. It is understood that further layers can be applied to the resulting layer material. These may in particular be color layers of printing and / or reinforcements in the form of further polymer materials and / or fiber materials. Suitably, the protective layer material is selected so that the protective layer can come into direct contact with a packaged medium, in particular a food, without fear of damage to the protective layer or impairment of the food. Thus, the interior of the packaging facing surface of the protective layer, in particular for beverage packaging from a liquid-impermeable material, such as polyethylene, may be formed. Conversely, in a packaging material for less sensitive and / or aggressive substances protection layer of a particularly good recyclable and / or decomposable material may be formed, for example, a polylactide.

expedient is the flexible carrier material made of a fibrous material Material formed. This may in particular be a material selected from the group comprising paper, cardboard, cellulose, Act felt and vegetable fiber materials. These materials are cheap and available in large quantities, are due to their non-toxicity to food packaging suitable and have a good impermeability Light up. Further, these materials are easily recyclable and environmentally neutral.

In an alternative embodiment is the flexible substrate selected from the group comprising plastics and biological degradable materials, the carrier material being particularly may preferably consist of polyethylene or polylactide. These materials are also for the production of food packaging very well suited, being polyethylene with per se known methods easily recyclable and polylactide is biodegradable.

It it is understood that on the side facing away from the diffusion barrier layer Side of the flexible substrate applied more layers can be. Especially when the diffusion barrier layer opposite side of the flexible carrier material to a Outside of a manufactured from the packaging material Packaging shows, a printing layer can be provided on this side become. Likewise, another protective layer, in particular a polymer material, another by means of a sputtering process applied layer, an adhesion-promoting layer or a combination be provided from these layers. If another means applied by a sputtering process applied layer of a metal is, by these advantageous a graphical representation, in particular in the form of a hologram.

Preferably is the packaging material produced by the process for Production of packaging, in particular for liquids or liquid-containing substances used. The packing can be folded and glued in a conventional manner or formed by lamination.

The Layer material according to the invention based on a fibrous carrier material, in particular for Packaging purposes, includes one on the substrate arranged metal-containing diffusion barrier layer and one on the metal-containing diffusion barrier layer arranged protective layer, wherein the metal-containing diffusion barrier layer on the carrier material evaporated. The thus formed layer material has a particularly easy to manufacture, opaque and mechanical loads against particularly stable diffusion barrier layer on. The diffusion barrier layer is advantageous here directly connected to the substrate without any intermediate Adhesive layer must be provided so that is beneficial a cohesive connection between the carrier material and diffusion barrier layer. The layer material thus has especially against thermal and mechanical stresses special Stability on.

Preferably is an adhesion-promoting layer between the metal-containing diffusion barrier layer and the protective layer. This makes it possible, a protective layer in a known per se on the diffusion barrier layer Apply by gluing. Alternatively, the protective layer made of a polymer material and is immediately without providing an adhesion promoting layer on the diffusion barrier layer applied. By means of both possibilities can be a liquid-tight Surface of the packaging material are created.

Preferably For example, the diffusion barrier layer comprises aluminum or an aluminum compound. A Diffusion barrier layer of aluminum or an aluminum compound produces advantageous a particularly opaque and oxygen-impermeable intermediate layer in the layer material.

expedient the thickness of the diffusion barrier layer is less than 5 micrometers, with a thickness of less than 1 micrometer being preferred is.

Preferably is the layer material as a folded vessel for liquid-containing substances used. Especially for Foods such as drinks or liquids pasty or solid foods can thus be an opaque, creating gas impermeable packaging material, which allows safe storage of food.

Further Features of the invention will become apparent from the following description preferred embodiments and from the dependent Claims.

The Invention will be described below with reference to the appended Figures closer on the basis of preferred embodiments explained.

1 shows a first embodiment of a layer material according to the invention in not true-to-scale cross-sectional view.

2 shows a second embodiment of a layer material according to the invention in not true to scale cross-sectional view.

3 shows a third embodiment of a layer material according to the invention in a non-scale true cross-sectional view.

This in 1 shown layer material 1 consists of a carrier layer of a carrier material 2 on which a diffusion barrier layer 3 and protective layer 4 are applied. The carrier material 2 has a thickness of about 1 mm and is made of cardboard. In the preferred use of the layer material 1 as a packaging material for liquid-containing substances that forms of the diffusion barrier layer 3 remote outer surface 5 of the carrier material 2 an outside of the outside facing the packaging. Accordingly, on the outside surface 5 a printing (not shown) may be provided. Alternatively, or additionally, may be to the outer surface 5 further layers of the layer material 1 connect, for example, a further diffusion barrier layer and / or a liquid-tight sealing layer.

The outer surface 5 of the carrier material 2 opposite surface forms a first interface 6 between the diffusion barrier layer 3 and the carrier material 2 out. Thereby, that the diffusion barrier layer 3 on the carrier material 2 was evaporated, is along the interface 6 a particularly intimate, material connection between the barrier layer material and the carrier material 2 given. It is advantageous that no adhesion promoter such as adhesive between the diffusion barrier layer 3 and the carrier material 2 is present. The diffusion barrier layer 3 is in this case made of pure aluminum, wherein the diffusion barrier layer 3 has a thickness of about 1 micrometer. It should be noted that the representation in 1 not to scale. In particular, there is also an unavoidable roughness of the first interface 6 in the illustration according to 1 not recognizable. An advantage of the formation of the diffusion barrier layer 3 by vapor deposition of the carrier material 2 is that, despite an unavoidable, at least atomic roughness of the substrate 2 a continuous, gap-free diffusion barrier layer 3 is trained.

Between the diffusion barrier layer 3 and the protective layer 4 is one of the first interface 6 opposite second interface 7 formed at the the diffusion barrier layer 3 to the protective layer 4 borders. The protective layer 4 is formed here of polyethylene and has a thickness of about 10 microns. The protective layer 4 is by direct application of the polyethylene material to the diffusion barrier layer 3 has been formed so that the diffusion barrier layer 3 and the protective layer 4 are directly interconnected materially. The protective layer 4 forms a liquid-tight layer, wherein in the preferred use of the layer material 1 as a packaging material for liquid-containing substances that of the diffusion barrier layer 3 opposite side surface 8th the protective layer 4 forms an interior of an inside facing the package.

It is understood that the protective layer 4 in an alternative embodiment of the layer material also by means of a along the second interface 7 applied adhesion-promoting layer with the diffusion barrier layer 3 can be connected. This is particularly advantageous if the protective layer is formed of a material that is of little use on the diffusion barrier layer 3 adheres; for example, if the protective layer 4 made of paper or cardboard. Preferably, in this case, further layer materials close to the protective layer 4 at least one of which forms a liquid-tight layer.

2 shows a further embodiment of a layer material 101 , Compared to the first embodiment are functionally comparable elements with 100 denoted by reference numerals.

The layer material 101 comprises a carrier layer of a carrier material 102 , which is formed here from Polylactidfolie. It is understood that alternatively, another polylactide-containing carrier material can be provided, for example a polylactide-containing woven or nonwoven fabric or a fiber-reinforced polylactide material. On the carrier material 102 is a diffusion barrier layer 103 sputtered from aluminum. It proves to be particularly advantageous that the polylactide has a very low surface roughness, so that the first interface 106 between the carrier material 102 and the diffusion barrier layer 103 runs very flat and already with a very thin diffusion barrier layer 103 With a thickness of less than 1 micron, a sufficiently high barrier effect, in particular with respect to the diffusion of oxygen molecules can be achieved. On the carrier material 102 opposite side of the diffusion barrier layer 103 is a protective layer 104 made of polyethylene, wherein between the diffusion barrier layer 103 and the protective layer 104 a second interface 107 is trained. The of the diffusion barrier layer 103 opposite side surface 108 the protective layer 104 indicates when using the coating material 101 as a packaging material for liquid-containing substances to an inside of the packaging, so that the protection layer 104 polyethylene forms a liquid-tight inside of the packaging material.

On the diffusion barrier layer 103 opposite outside 105 of the carrier material 102 is a print layer 109 applied, which when using the layer material 101 as packaging material facing an outer area of the packaging. By means of the print layer 109 On the outside of the packaging information and graphics can be reproduced. Alternative to the print layer 109 may be a hologram (not shown) on the substrate 102 be arranged.

The layer material 101 has the advantage that it is particularly easy to recycle. By heating the layer material, the polylactide portion can be easily melted off and removed so that only the protective layer 104 made of polyethylene and because of the small thickness of the barrier layer 103 negligible aluminum content remains. The remaining protective layer 104 made of polyethylene can therefore be reused directly by means of the usual for polyethylene films recycling process.

3 shows a further embodiment of a layer material 201 , Compared to the first embodiment are functionally comparable elements with 200 denoted by reference numerals.

The layer material 201 comprises a carrier layer of a carrier material 202 made of paper. On when using the coating material 201 Inner side of the carrier material turned as packaging material into a packaging interior 202 is a first diffusion barrier layer 203 made of aluminum by means of an evaporation process. On the first diffusion barrier layer 203 is a first protective layer 204 made of polyethylene, whose surface 208 forms a liquid-tight inside.

On the outside facing away from the inside 205 of the carrier material 202 is a second diffusion barrier layer 210 applied, the present one of the first diffusion barrier layer 203 corresponding thickness and texture. To the second diffusion barrier layer 210 closes a second protective layer 211 on, like the first protective layer 204 made of polyethylene. That of the second diffusion barrier layer 210 remote second protective layer 211 forms an outer surface 212 of the layer material 201 , It is understood that on the outside surface 212 also a printing layer (not shown) or a hologram (not shown) may be arranged. By providing a second diffusion barrier layer 210 and a second protective layer 211 a particularly resistant layer material is created.

above were different embodiments of an inventive Layer material exemplified. It goes without saying that in each of the described embodiments, layer sequences changed or supplemented by further layers can be. It is further understood that described Materials of functionally comparable layers interchanged can be.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• EP 1285744 B1 [0003]
• - DE 19502103 B4 [0004]

Claims (17)

Method for producing a packaging material ( 1 ; 101 ; 201 ), comprising the steps of providing a flexible carrier material ( 2 ; 102 ; 202 ), Applying a metal-containing diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) on the carrier material ( 2 ; 102 ; 202 ), and applying a protective layer ( 4 ; 104 ; 204 . 211 ) on the diffusion barrier layer ( 3 ; 103 ; 203 . 210 ), characterized in that the application of the diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) on the carrier material ( 2 ; 102 ; 202 ) takes place by means of a vapor deposition process. Method according to claim 1, characterized in that that the sputtering process is selected from the group comprising physical vapor deposition, in particular sputtering and / or thermal evaporation processes, and chemical vapor deposition. Method according to claim 1 or 2, characterized in that the metal-containing diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) Aluminum. Method according to one of claims 1 to 3, characterized in that the thickness of the diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) is less than 5 microns. Method according to one of claims 1 to 4, characterized in that the application of the protective layer ( 4 ; 104 ; 204 . 211 ) on the diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) by means of an adhesive method. Method according to one of claims 1 to 5, characterized in that the protective layer ( 4 ; 104 ; 204 . 211 ) comprises a polymer material and / or a fiber material. Method according to one of claims 1 to 6, characterized in that the flexible carrier material ( 2 ; 102 ; 202 ) is formed of a fibrous material. Method according to one of claims 1 to 7, characterized in that the flexible carrier material ( 2 ; 102 ; 202 ) is selected from the group comprising paper, cardboard, cellulose, felt and vegetable fiber materials. Method according to one of claims 1 to 7, characterized in that the flexible carrier material ( 2 ; 102 ; 202 ) is selected from the group comprising plastics, in particular polyethylene, and biodegradable materials, in particular polylactide. Packaging material produced by a process according to one of claims 1 to 9. Packaging, in particular for liquids, at least predominantly formed from a packaging material according to claim 10. Packaging according to claim 11, characterized in that the diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) of the packaging material on a side of the carrier material ( 2 ; 102 ; 202 ) is arranged. Layer material based on a biodegradable support material ( 2 ; 102 ; 202 ), in particular for packaging, comprising one on the substrate ( 2 ; 102 ; 202 ) arranged metal-containing diffusion barrier layer ( 3 ; 103 ; 203 . 210 ), and one on the metal-containing diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) arranged protective layer ( 4 ; 104 ; 204 . 211 ), characterized in that the metal-containing diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) on the carrier material ( 2 ; 102 ; 202 ) is evaporated. Layer material according to claim 13, characterized in that an adhesion-promoting layer between the metal-containing diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) and the protective layer ( 4 ; 104 ; 204 . 211 ) is arranged. Layer material according to claim 13 or 14, characterized in that the diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) Aluminum or an aluminum compound. Layer material according to one of claims 13 to 15, characterized in that the thickness of the diffusion barrier layer ( 3 ; 103 ; 203 . 210 ) is less than 5 microns. Use of the layer material according to one of the claims 13 to 16 as a folded vessel for liquid-containing Substances.