Environmentally friendly, cardboard-based blister packaging

Abstract

The subject of the invention relates to environmentally friendly, cardboard-based blister packaging, furthermore to a blister card that may be used for blister packaging, and to a method for the production of the blister card, in the case of which the blister card (1) may be removed from the blister film (2) without residue, and as a result of this the paper and plastic components of the packaging may be selectively collected. An important feature of the solutions according to the invention is that with the method for the production of the blister card (1) a novel unique layer order is created as a result of which the blister card (1) and the blister film (2) do not come into contact with each other in any way whatsoever, and this makes it possible to separate the two types of material without contamination, and without tearing up any fibres.

Description

[0001] ENVIRONMENTALLY FRIENDLY, CARDBOARD-BASED BLISTER PACKAGING

[0002] The subject of the invention relates to environmentally friendly, cardboard-based blister packaging, which has a blister card made from cardboard and blister film with a pocket corresponding to the shape of the packaged product, the blister film is provided with a securing flange surrounding the pocket.

[0003] The subject of the invention also relates to a blister card that may be used for environmentally friendly, cardboard-based blister packaging, which has a cardboard sheet and a heat sealing coating.

[0004] The subject of the invention also relates to a method for the production of the blister card.

[0005] Overall the subject of the invention relates to environmentally friendly, cardboard-based blister packaging and a blister card that may be used to create it, which, after use, make it possible for the plastic and paper components to be separated from each other essentially without any residual material, through which their disposal as selective waste may be realised. This preferable feature of the blister card is a consequence of the special structure, which, in addition to the appropriate layer arrangement, is also a consequence of the production process method used for the production of the card.

[0006] Blister packaging is a packaging method in which the packaged product is enclosed between a blister film made from a transparent plastic sheet or roll and a backing sheet made from cardboard, occasionally a plastic sheet, aluminium foil or a material composed of these, the so-called blister card. During the preparation of the packaging process the plastic sheet or roll is thermally shaped to conform to the shape of the packaged product, then leaving a securing flange surrounding the thermally shaped cavity, it is cut to shape. The blister card, in this case made from cardboard, after having the appropriate graphic elements applied to it using offset printing, is provided with a heat sealing varnish layer. This varnish layer has a dual role. On the first part, it protects the layer of ink carrying the graphic elements and thereby provides the cardboard sheet with a pleasant appearance and a shiny surface, and, on the other part, this varnish layer provides, after the packaging process, the rigid bond between the cardboard blister card and the blister film.

[0007] During packaging the packaged product is placed in a pre-made cavity in the blister film, and then the cardboard blister card and the blister film are fitted up to one another. After this, the blister film is baked onto the blister card using a tool made for this purpose, which, in practice, means that the securing flange of the blister film is pressed onto the cardboard sheet with the application of an appropriate thermal effect. As a consequence of the pressure applied for an appropriate amount of time and the thermal effect , the heat sealing varnish secures the blister film to the blister card along the securing flange.

[0008] In practice the bond created between the heat sealing varnish layer and the blister film is so strong that its tensile strength usually exceeds the internal tensile strength of the cardboard itself. The consequence of this is that, on opening, the packaging does not separate along the meeting line between the heat sealing varnish and the blister film, instead paper fibres are torn out of the cardboard blister card, which, being stuck to the securing flange of the blister film make it difficult to separate the paper and plastic without residual material.

[0009] Multiple use options of blister cards according to the state of the art are presented on pages 92-101 of the book entitled “Csomagolasgepesites 1. Fogyasztoi Csomagolas” [Packaging mechanisation 1, Consumer Packaging] (ISBN:2310001912836).

[0010] The increasingly stricter environmental protection prescriptions are demanding 100% recyclability, one condition for which is the selective collection of plastic and paper constituent elements.

[0011] The solutions currently known of that ensure the separation without residual material of plastic and paper constituents with consideration to environmental aspects approach the problem from several directions.

[0012] The subject of patent document number US2008217199A1 is environmentally friendly plastic-cardboard blister packaging that may be separated. The essence of the solution is that the blister film that has a flange is placed between two cardboard sheets, where the first cardboard sheet is cut out in the shape corresponding with the product storage pockets of the blister film, thereby the 3 layers lie on each other. The sealing of the packaging takes place by gluing together the two cardboard sheets immediately around the flange of the blister film. When the packaging is opened the packaged product may be simply lifted out of the product storage pocket by separating the two cardboard sheets. In this way, as there is no adhesive connection created between the plastic film and the cardboard elements, the plastic and cardboard elements of the packaging may be separated from each other without any residual material and collected selectively.

[0013] The less significant disadvantage of the solution is that even with the use of double the amount of paper, it does not ensure the hermetic sealing of the packaged product, while the really serious problem is that its introduction demands a complete change of process technology, because the conventional blister pack packaging machines cannot be used with this solution.

[0014] The study on the recycling of pharmaceutical blister films accessible on the internet site: https: / / www.sciencedirect.com / science / article / pii / S2772912523000088 presents various chemical solutions for separating the blister film, paper and aluminium as well as multilayer base sheets following use that dissolve the adhesive layer or break down the individual components. These solutions may be preferable for hospitals or nursing homes, for example, where a large amount of blister film waste is created at the same time, but do not represent a solution for occasional users in the appropriate environmentally friendly treatment of individual blister packages.

[0015] In addition to the two concrete examples above, there is also a tendency to completely leave out the transparent blister film from packaging of this type. This is achieved by making the product-holding pocket from cardboard, similarly to the base sheet, the picture of the packaged product is applied to this by printing, and then after inserting the product, the two cardboard elements are glued together.

[0016] It is indubitable that in the case of this solution no plastic waste is created when the packaging is taken apart, therefore it is possible to selectively collect the waste created and recycle it. Its disadvantage, however, is that when the customer makes his / her consumption decision does not see the actual product only an image of it, and so in this way the consumer is unable to determine the quality of production of the product, or the quality of the materials used.

[0017] ,\nother feature that maybe mentioned as a disadvantage of this solution is that this form of packaging cannot be implemented using conventional blister packaging machines. When elaborating the solutions according to the invention we set the objective of creating an environmentally friendly, cardboard-based blister card and, using this, blister packaging, and in the case of the use of this blister card in blister packaging when opening the blister packaging the plastic blister film and the cardboard blister card components may be separated essentially without leaving and residual material, in other words the plastic component may be removed free of any paper residue, and at the same time the conventional blister packaging machines may be used during packaging without any obstacle.

[0018] When elaborating the invention, we set the objective of elaborating a method for the production of the environmentally friendly cardboard blister card described above, and which, with the appropriate selection of the steps of the method, the production parameters and the material characteristics, is suitable for production of a blister card with the desired characteristics at industrial scales.

[0019] An additional objective was to elaborate a method with which the blister card is created in such a way so that the blister card and the blister film may be separated without residue when the packaging is opened, as conventional blister card production technologies are not suitable for the production of such blister cards. It was also an objective for the method to be suitable for the production of the blister card with the desired characteristics at industrial scales by suitably selecting the blister card production method steps, the production parameters and the material characteristics.

[0020] The basis of the idea behind the invention was formed by the recognition that if the blister film is not baked directly to the surface of the cardboard of the blister card but, instead, onto an intermediate plastic separator film, which separator film is affixed to the cardboard surface via connection to the heat-resistant varnish layer coating the surface of the cardboard, then the task may be solved.

[0021] The idea behind the invention also constituted the recognition that it is necessary to place a layer, i.e. a separator film onto the blister card that ensures that the heat sealing vamish is not able to seep in between the fibre of the cardboard sheet when the blister film is baked on, in this way, if unconventional method steps and contributory parameters are used, then the separator film may be reliably applied to the surface of the blister card, and with this the separator film ensures that the blister film may be separated from the blister card without tearing up fibres, and so the task may be solved. In accordance with the set objective, the environmentally friendly, cardboard-based blister packaging according to the invention, - which has a blister card made from cardboard and blister film with a pocket corresponding to the shape of the packaged product, the blister film is provided with a securing flange surrounding the pocket, - is set up in such a way that at least one of the sides of the blister card is coated with a heat-resistant varnish layer, a separator film is affixed to the heat-resistant varnish layer using adhesive, and the other side of the separator film is provided with a heat sealing coating.

[0022] A further feature of the blister packaging according to the invention may be that the heat- resistant varnish layer is a water-based offset varnish.

[0023] In the case of another version of the invention, the separator film is a biaxially-oriented coextruded polypropylene film.

[0024] In the case of another different embodiment of the blister packaging at least one start mark is arranged on the blister card.

[0025] In accordance with the set objective, the following blister card according to the invention for environmentally friendly, cardboard-based blister packaging, - which has a cardboard sheet and a heat sealing coating, - is set up in such a way that a separator film is affixed to the one side of the cardboard sheet preferably using adhesive, and the side of the separator film opposite to the cardboard sheet is provided with a heat sealing coating.

[0026] A further feature of the blister card according to the invention may be that at least the side of the cardboard sheet facing the separator film is coated with a heat-resistant varnish layer.

[0027] In the case of a further embodiment of the invention, the heat-resistant varnish layer is a water-based offset varnish.

[0028] In the case of another version of the blister card, the separator film is a biaxially-oriented coextruded polypropylene film.

[0029] In the case of another different embodiment at least one start mark is arranged on the blister card.

[0030] In accordance with the additional set objective, the method according to the invention for the production of an environmentally friendly blister card is based on the principle that the from side of the cardboard sheet is coated with a heat-resistant varnish layer, additionally one side of the separator film is coated with a heat sealing coating, following this, the other side of the separator film and the front side of the cardboard sheet coated with a heat-resistant varnish layer are affixed together using peel-off adhesive, then the blister card is cut to size as required.

[0031] A further feature of the method according to the invention may be that a dispersion varnish heat-resistant up to 240 °C is used as the heat-resistant varnish layer.

[0032] In the case of another implementation of the method the application of the heat-resistant varnish layer is performed using a large-dip screen roller.

[0033] In the case of another embodiment of the method according to the invention, flexo varnish is used as the heat sealing coating, which is applied to the surface of the separator film using flexo technology.

[0034] In the case of yet another different version of the method, the application of the heat sealing coating is performed with an anilox screen roller.

[0035] In the case of yet another different implementation of the method, during the coating with the heat sealing coating, the heat sealing coating is applied using a photopoiymer plate and then dried using hot air at a temperature of 80 °C.

[0036] In the case of another implementation of the method overprint varnish is used as the heat sealing coating, which is applied to the surface of the separator film using gravure printing technology.

[0037] From the point of view of the method according to the invention it may be preferable if the cutting to size is performed using stamping or by cutting out.

[0038] In the case of another different version of the method, the cutting to size is performed using straight cutting.

[0039] In the following embodiments that support the scope of the protection are presented with reference to figures, wherein

[0040] Figure 1 depicts a perspective view of an embodiment of the blister packaging made using the blister card according to the invention, Figure 2 depicts a schematic cross-sectional view of the blister packaging according to the invention taken at the securing flange,

[0041] Figure 3 depicts a cross-sectional view of a version of the blister card according to the invention.

[0042] Figure 1 shows a possible version of the blister packaging made using the blister card 1 according to the invention, after the packaging has been performed, but in a state without the packaged product. The two main constituent elements of the blister packaging are the blister card 1 and the blister film 2 according to the invention. In the present case the blister card 1 is rectangular, and has rounded off comers, and is provided with a start mark 8 on the side facing the blister film 2. The blister film 2 has a pocket corresponding to the shape of the packaged product, following the contours of the product, and preferably created using thermoforming. A securing flange 3 is created around the pocket, closely surrounding it. The securing flange 3 preferably represents the edge of the blister film 2. in other words it constitutes its outline. The shape and rigidity of the blister card 1 is provided by the cardboard sheet la marked in figure 2.

[0043] Moving over now to figure 2, it may be observed in it that in the case of this version the heat- resistant varnish layer 5 covers the entire surface of the cardboard sheet la on the side of the packaged product. The separator film 4 is affixed to the heat-resistant varnish layer 5 with adhesive 7. A heat sealing coating 6 may be found on the side of the separator film 4 opposite the cardboard sheet la.

[0044] The start mark 8 of the cardboard sheet la coated with the separator film 4 obtains a function when the separator film 4 is removed from the cardboard sheet la.

[0045] While the product is being packaged the product to be packaged is placed into the product pocket of the blister film 2, then the blister film 2 and the blister card 1 covered with the separator film 4 are fitted together in such a way that the securing flange 3 on the blister film 2 rests on the blister card 1 , more precisely on the heat sealing coating 6 of the separator film 4. Following this, using a dedicated tool, the blister film 2 is baked onto the separator film 4 along the securing flange 3 by melting the heat sealing coating 6. It is important to emphasise that the packaging process and the apparatus used for this are exactly the same in the case of the blister packaging according to the invention and in the case of conventional packaging. When creating the invention this was an important objective which when implemented in accordance with the invention ensures that the packaging machines used in the past may continue to be used for sealing the packaging according to the invention without being changed.

[0046] The heat-resistant property of the heat-resistant varnish layer 5 has significance when sealing the packaging, the reason for this is that in the lack of this during the packaging process, when the blister film 2 is baked on, the adhesive 7 securing the separator film 4 may melt and a bond with the cardboard sheet 1 a of a strength exceeding the internal tensile strength of the cardboard may be created, which makes it impossible to remove the separator film 4 from the cardboard sheet la without causing damage. The heat-resistant varnish layer 5 created on the cardboard sheet la prevents the adhesive 7 securing the separator film 4 and melting during baking from seeping between the paper fibres of the cardboard sheet 1 a and thereby prevents a bond of undesired strength being created between the separator film 4 and the cardboard sheet la. In the interest of this a heat-resistant varnish layer 5 is used to coat the surface of the cardboard sheet la that has a heat-resistance that is in excess of the thermal loading elicited during the baking process.

[0047] When the packaging is opened the user first removes the blister film 2 from the blister card 1 coated with the separator film 4. In practice this means the destructive opening of the bond created by the heat sealing coating 6 between the separator film 4 and the blister film 2, where the tensile force exerted between the blister film 2 and the blister card 1 exceeds the adhesive or breaking strength of the heat sealing coating 6.

[0048] In the case of the solution according to the invention, during the removal of the blister film the paper fibre contamination problem occurring in the case of conventional blister packaging does not occur during the removal of the blister film 2, because the blister film 2 does not come into contact with the cardboard material of the cardboard sheet la.

[0049] Following this, starting preferably at the start mark 8, the user pulls the separator film 4 from the blister card L At this time the separator film 4, along with the adhesive 7 present on it, becomes separated from the heat-resistant varnish layer 5 coating the cardboard sheet la. With a view to that the heat-resistant varnish layer 5 has prevented an undesired increase in binding force between the separator film 4 and the blister card 1 in the vicinity of the securing flange 3, the separator film 4 may be pulled off the blister card 1 with an even force without obstruction. In other words, according to the above the paper-based cardboard sheet la may be non-destructively separated from the plastic separator film 4, as well as from the, also plastic, blister film 2, thereby enabling the selective collection of the individual components of the used packaging.

[0050] Moving over to figure 3, it shows a cross-sectional view of the structural arrangement of a possible embodiment of the blister card 1.

[0051] The separator film 4 covers the entire surface of the packaged product-side of the cardboard sheet la. The adhesive 7 secures the separator film 4 to the surface of the cardboard sheet la. On its side opposite to the cardboard sheet la the separator film 4 is provided with a heat sealing coating 6. The securing flange 3 of the blister film 2 is located on the side of this heat sealing coating 6 opposite to the separator film 4. The heat-resistant varnish layer 5 indicated in figure 2, does not appear here, but its presence improves the full separation of the blister film 2 and the blister card 1.

[0052] In the case of the blister card 1 according to the invention, the function-oriented selection of the binding materials and the individual material properties has particular significance in the interest of the separation during the opening of the packaging taking place between the blister film 2 and the separator film 4, and so that the packaging technology does not differ from that used previously.

[0053] T his is achieved by determining the order of the layers as a result of the tests performed continuously during the development process, as well as the concentration of the binding materials used. Heat sealing varnish is used on the printed cardboard surface in the case of conventional blister packaging, with which the blister film creates a bond strong enough to safely retain the product, and protect it from external impacts and contamination. However, this strong bond is damaging when the packaging is opened, in accordance with the objective of the invention the strong bond between the blister film 2 and the upper layers of the cardboard sheet la of the blister card 1 had to be eliminated. An additional heat-resistant layer of varnish would not be a solution in itself, as the two layers with opposite functions are not compatible, in addition the complete drying of the varnish is questionable when applied at this thickness. If the blister film 2 were to be directly baked onto the heat-resistant varnish, the bond would not be formed with the blister card 1 due to the heat-resistant properties of the layer. The same problem would be created if the heat-resistant varnish were to be placed under the heat sealing varnish. The heat sealing varnish layer cannot be in contact with the cardboard.

[0054] This means that the heat sealing varnish needs a separate carrying layer. It must also be possible to remove the separator film 4 layer, which is used as carrying layer, without the creation of cardboard fibre contamination, as the purpose of the whole packaging is selective collection.

[0055] The commercially available repositionable film that is already provided with adhesive is not suitable for this purpose, as heat sealing varnish cannot be applied to it. Due to this the film layer is applied to the cardboard surface with the use of a repositionable adhesive 7. However, the adhesive 7 does not have a heat-resistant property, due to this when the blister film 2 is baked on the now dried adhesive 7 softens along the securing flange 3 in the heat sealing zone and creates a similarly strong bond in the upper layer of the cardboard, which also means that fibres will be tom up when the packaging is separated. In order to avoid this, during the printing step a heat-resistant varnish layer 5 is applied to the cardboard surface, which prevents the adhesive 7 becoming adhered to the cardboard surface, at the same time it does not inhibit the repositionable property of the dried adhesive 7 and provides suitable adhesion for the separator film 4.

[0056] In the solution according to the invention the heat-resistant varnish layer 5 is preferably a water-based offset varnish, which has a high-gloss property, dries quickly, is highly wearresistant and is sufficiently flexible for the assembly. It is a glossy varnish that was developed for the production of packaging required for subsequent heat-shaping, and has a high resistance to heat. After heat-shaping the varnish does not lose its water and grease resistance.

[0057] Biaxially-oriented coextraded polypropylene film that may be welded, is non-toxic and thereby suitable for use as food packaging is preferably used as the separator film 4. It is strong and light, and is resistant to both high and low temperatures. In spite of its low density, it has a high tensile strength. During production the film is stretched in both the longitudinal and lateral directions, in this way its size increases, and its thickness and lateral breaking strength are reduced. The advantages of the use of biaxially-oriented polypropylene (BOPP) film include its ease of welding, outstanding glossiness and its resistance to mechanical impacts. In addition to this it is taste and odour-neutral. In the following the method according to the invention is presented in more detail. In advance of the detailed presentation it must be stated in general that at the beginning of the development we performed test productions taking the most logical and simplest technological approach. For this we acquired commercially available corona treated PET film manufactured with an adhesive layer for use as the separator film and applied it to the printed surface on the machine owned by the subcontractor employed in the project.

[0058] The adhesion of the film onto the cardboard was implemented, and it could be pulled off the surface of the cardboard, although this was quite difficult. The main problem here was the adhesion of the PET. blister film, during the internal tests this was only fulfilled partially in the heat sealing zones (180 - 210 °C), which represents a risk from the point of view of the safe storage of the packaged product. We found it to be essential to coat the separator film with heat sealing varnish in advance, which guarantees appropriate heat sealing even in the case of conventional blister packaging. Also, it is not possible to apply varnish to thermofilm.

[0059] We saw the solution in continuing the tests with cold film application. In this technology method while the film is being applied the adhesive layer is applied between the cardboard and the film. An adhesive is required that makes it possible to remove the separator film from the surface of the cardboard. We found a type of adhesive that allows this. Corona treated 25 micron and 12 micron PET film originating from several suppliers was tried out during cold film application. All of these proved to be of very bad quality in terms of their running on the film application machine (cutting of curves, laying flat) and in terms of their performance during the test welding.

[0060] Producing the separator film from PET material proved to be a dead end, so we transferred our attention to BOPP film, which presented no problems when cutting curves. The laying flat of the 30 micron thick film tested first was not satisfactory, and the colour and appearance of the print was very distorted.

[0061] The next step was to test the thinner, 15-micron BOPP film, which ran well on the machine and was easy to cut, and did not negatively affect the appearance of the print.

[0062] We started to test this film type with heat sealing varnish. After the tests were completed we obtained varnishing parameters that, beside conventional blistering parameters (180 - 210 °C) guaranteed a strong bond between amorphous polyethylene terephthalate (APET) blister film and the separator film. Already during the tests in connection with the heat sealing varnish we experienced that due to the effect of the high temperature a strong bond was created by the peel-off adhesive applied between the separator film and the cardboard between the two material surfaces in the heat sealing zone. This resulted in that it was not possible to peel off the separator film from the print without tearing up the cardboard.

[0063] Then, after solving the blistering of the film, an additional problem had to be solved. The heat-resistant varnish was introduced into the experiments, which had been applied to the surface of the cardboard sheet during the printing step. The function of this layer is to prevent the transfer of heat between the adhesive and the cardboard, and so the strong adhesive bond between the cardboard and the adhesive was eliminated in the heat sealing zones.

[0064] In summary the joint use of the heat-resistant surface of the cardboard sheet (front side), the peel-off adhesive applied to the separator film, and the heat sealing varnish applied to the opposite side (the side facing the blister film) ensures the retention and protection of the product, and disposal as selective waste after the packaging has been opened, and the blister card produced with the method according to the invention may be processed on the automatic packaging machines of the packaging contractors in the same way as conventional blister cards.

[0065] In the following the method according to the invention is presented in detail with reference to examples.

[0066] Example 1:

[0067] During the production of the environmentally friendly blister card 1 according to the invention, first of all the cardboard sheet constituting the frame of the blister card 1 is prepared. The front side of the cardboard sheet facing the packaging was coated with a heat- resistant varnish layer 5. The task of the heat-resistant varnish layer is to prevent the peel-off adhesive 7 from seeping between the fibres of the cardboard sheet la when the blister packaging is sealed, in other words when the blister film is baked on. Accordingly, the heat- resistant varnish used was a dispersion varnish that is heat resistant up to a heat effect of at least 240 °C. The application of the heat-resistant varnish layer was performed with a large- dip screen roller, preferably with offset technology. Optionally, using the offset technology, the heat-resistant varnish layer 5 was applied to the cardboard sheet la together with the layer of ink providing the surface pattern of the blister card 1. In addition to the above and independently of the above we also produced the separator film 4. During this the separator film 4 was provided with a heat sealing coating 6. Here, this work process was performed using high-pressure flexo technology, during which flexo varnish was applied to the surface of the separator film 4. It should be noted here that flexo printing is a raised printing technique that uses flexible printing forms and low-viscosity inks and varnishes, and the printing can take place from roll to roll. During this photopolymer printing plates were used that we positioned between the rotating rollers. In order to promote faster drying we used air at a temperature of 80 °C, and quick-drying ink or varnish, and we used a screen roller to apply the ink or the varnish to the printing form. We used an anilox roller to apply the heat sealing coating 6 with flexo printing.

[0068] After coating the front side of the cardboard sheet la with the heat-resistant varnish layer 5 and the surface of the separator film 4 with the heat sealing coating 6 the surface of the separator film 4 without the coating was combined with the front side of the cardboard sheet la coated with the heat-resistant varnish layer 5 using peel-off adhesive 7, in other words they were glued together.

[0069] An aqueous dispersion adhesive was used as the peel-off adhesive 7, the advantage of which is that it does not contain organic solvents or materials that are hazardous to health, and does not constitute a fire hazard. Without being exhaustive, such adhesive basic material may be, for example, an aqueous dispersion of an acrylic acid ester copolymer or an aqueous dispersion of styrene acrylic copolymer.

[0070] The combining of the cardboard sheet la and the separator film 4 was performed in the given example using a film lamination machine, where the separator film 4 was fed from a roll of film into the application unit. The peel-off adhesive used as the adhesive 7 was loaded into the application unit, applied to the separator film 4 and evenly distributed. The separator film 4 coated with the peel-off adhesive used as the adhesive 7 was pre-dried on a heated lamination roller during transportation. The cardboard sheet la coated with the heat-resistant varnish layer 5 was fed into the lamination unit via a sheet feeder. The separator film 4 and the cardboard sheet la were fitted up to each other, and then the two materials were glued together under pressure between the lamination and the counter-rollers, and then the film as cut to size. Following this the cardboard glue together with the separator film 4 was forwarded to the sheet delivery unit of the machine. The cutting to size of the environmentally friendly blister card 1 may be performed in multiple ways. It may be performed during production, but also independently, or when the product is packaged as the first step of use. Accordingly, cutting to size may mean establishing the transportation or storage size, but it may also mean the cutting of the blister card 1 to the shape corresponding to the blister packaging. The cutting to size may be implemented by stamping or cutting, with straight cutting, or using other processes, such as laser cutting.

[0071] Example 2:

[0072] In the case of the given method the process was the same as the previous with the difference that the heat sealing coating 6 was applied to the surface of the separator film 4 using gravure printing technology, and overprint varnish was used for this.

[0073] The most important practical advantage of the blister card according to the invention is that it makes it possible to separate, and collect selectively, the plastic and paper components created during the opening of the packaging in a much better way compared to the conventional solutions. In addition to all this in order to implement the packaging process there is no need to acquire new equipment, the packaging may be implemented using the previously used blister packaging machines without them having to be changed.

[0074] An important advantage of the blister packaging according to the invention is that as the heat- resistant varnish layer has prevented the undesired increase in the binding force between the separator film and the blister card in the vicinity of the securing flange, the separator film may be pulled off the blister card with an even force without obstruction, and in this way these structural elements can be essentially completely separated from each other.

[0075] An advantage of the method according to the invention is that as a result of it the production of the new type of environmentally friendly blister card may be implemented at industrial scales. List of reference signs blister card la cardboard sheet blister film securing flange separator film heat-resistant varnish layer heat sealing coating adhesive start mark

Claims

Claims1. Environmentally friendly, cardboard-based blister packaging, which has a blister card (1) made from cardboard and blister film (2) with a pocket corresponding to the shape of the packaged product, the blister film (2) is provided with a securing flange (3) surrounding the pocket, characterised by that at least one of the sides of the blister card (1) is coated with a heat-resistant varnish layer (5), a separator film (4) is affixed to the heat-resistant varnish layer (5) using adhesive (7), and the other side of the separator film (4) is provided with a heat sealing coating (6).

2. Blister packaging according to claim 1, characterised by that the heat-resistant varnish layer (5) is a water-based offset varnish.

3. Blister packaging according to claim 1 or 2, characterised by that the separator film (4) is a biaxially-oriented coextruded polypropylene film.

4. Blister packaging according to any of claims 1 to 3, characterised by that at least one start mark (8) is arranged on the blister card (1).

5. Blister card for environmentally friendly, cardboard-based blister packaging, which has a cardboard sheet (la) and a heat sealing coating (6), characterised by that a separator film (4) is affixed to the one side of the cardboard sheet (la) preferably using adhesive (7), and the side of the separator film (4) opposite to the cardboard sheet (la) is provided with a heat sealing coating (6).

6. Blister card according to claim 5, characterised by that at least the side of cardboard sheet (la) facing the separator film (4) is coated with a heat-resistant varnish layer (5).

7. Blister card according to claim 6, characterised by that the heat-resistant varnish layer (5) is a water-based offset varnish.

8. Blister card according to any of claims 5 to 7, characterised by that the separator film(4) is a biaxially-oriented coextruded polypropylene film.

9. Blister card according to any of claims 5 to 8, characterised by that at least one start mark (8) is arranged on the blister card.

10. Method for the production of an environmentally friendly blister card, characterised by that the front side of the cardboard sheet (la) is coated with a heat-resistant varnish layer(5), additionally one side of the separator film (4) is coated with a heat sealing coating (6), following this, the other side of the separator film (4) and the front side of the cardboard sheet (la) coated with a heat-resistant varnish layer (5) are affixed together using peel-off adhesive (7), then the blister card (1) is cut to size as required.11 Method according to claim 10, characterised by that a dispersion vamish heat- resistant up to 240 °C is used as the heat-resistant varnish layer (5).

12. Method according to claim 10 or 11, characterised by that the application of the heat- resistant vamish layer (5) is performed using a large-dip screen roller.

13. Method according to any of claims 10 to 12, characterised by that flexo varnish is used as the heat sealing coating (6), which is applied to the surface of the separator film (4) using flexo technology.

14. Method according to any of claims 11 to 13, characterised by that the application of the heat sealing coating (6) is performed with an anilox screen roller.

15. Method according to any of claims 10 to 14, characterised by that during the coating with the heat sealing coating (6), the heat sealing coating (6) is applied using a photopolymer plate and then dried using hot air at a temperature of 80 °C.

16. Method according to any of claims 10 to 15, characterised by that overprint varnish is used as the heat sealing coating (6), which is applied to the surface of the separator film (4) using gravure printing technology.

17. Method according to any of claims 10 to 16, characterised by that the cutting to size is performed using stamping or by cutting out.

18. Method according to any of claims 10 to 16, characterised by that the cutting to size is performed using straight cutting.

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