SUSTAINABLE BLISTER PACKAGING

Abstract

A blister packaging comprises a thermoformed web (30) with cavities (10) for a product formed therein, comprising at least two co-extruded layers: a main layer (34) comprising HDPE and up to 2% of a first additive, and a sealing layer (36) comprising HDPE and at most 50% of LLDPE, and a flat lid (20), comprising at least three co-extruded layers: an outer HDPE layer (22) containing up to 5% of a second additive, an intermediate HDPE layer (24) comprising a third additive suitable to decrease elongation at break, and an inner sealing layer (26), wherein the thermoformed web (30) and the flat lid (20) are heat-sealed together. The invention further relates to a packaged pharmaceutical or nutritional product comprising a comprising such a blister packaging, and a pharmaceutical or nutritional product (40) in solid form contained in the cavities. It further relates to a method for producing such a product.

Claims

1. A blister packaging comprising a thermoformed web (30) with cavities (10) for a product formed therein, comprising at least two co-extruded layers: a main layer (34) comprising HDPE and up to 2% of a first additive, and a sealing layer (36) comprising HDPE and at most 50% of LLDPE, and a flat lid (20), comprising at least three co-extruded layers: an outer HDPE layer (22) containing up to 5% of a second additive, an intermediate HDPE layer (24) comprising a third additive suitable to decrease elongation at break, and an inner sealing layer (26), wherein the thermoformed web (30) and the flat lid (20) are heat-sealed together.

2. A blister packaging according to claim 1 characterised in that the first additive in the main layer (34) of the web (30) is an inorganic additive.

3. A blister packaging according to claim 1 characterised in that the second additive in the outer HDPE layer (22) of the lid (20) is an inorganic additive.

4. A blister packaging according to claim 1 characterised in that the first additive in the main layer (34) of the web (30), the second additive in the outer HDPE layer (22) of the lid (20), and the third additive suitable to decrease elongation at break in the intermediate HDPE layer (24) of the lid, are all present in an amount of at least 0.2% in their respective layers.

5. A blister packaging according to claim 1 characterised in that prior to thermoforming the web (30) has a total thickness of 200-600 ?m, preferably 150 to 500 ?m, more preferably 250 to 400 ?m, and/or in that the lid (20) has a total thickness of 30-300 ?m, preferably 50 to 200 ?m, most preferably 80 to 110 ?m.

6. A blister packaging according to claim 1 characterised in that the overall polyolefin content of the blister packaging without a product is above 90%, preferably above 96%.

7. A blister packaging according to claim 1 characterised in that the web and the lid both contain an oxygen barrier layer.

8. A blister packaging according to claim 1, characterised in that the elongation at break of the lid is below 20%, preferably below 10%.

9. A blister packaging according to claim 1, characterised in that the inner sealing layer (26) of the lid (20) consists mainly of an ethylene copolymer, preferably a copolymer comprising Ethylene and vinyl acetate.

10. A blister packaging according to claim 1, characterised in that the inner sealing layer (26) of the lid (20) has a thickness of about 5 to 30 ?m, preferably of about 15 to 25 ?m.

11. A blister packaging according to claim 1 characterised in that the inner sealing layer (26) of the lid (20) comprises up to 2%, preferably up to 1% by weight of a slip agent.

12. A blister packaging according to claim 1 characterised in that the third additive in the intermediate HDPE layer (24) of the lid (20) is an inorganic additive, preferably selected from CaCO.sub.3, TiO.sub.2, Talc, chalk, clay or a metallic salt.

13. A blister packaging according to claim 1, characterised in that the third additive in the intermediate HDPE layer (24) of the lid (20) is a polymer which is incompatible with HDPE.

14. A blister packaging according to claim 1 characterised in that the sealing layer (36) of the thermoformed web (30) comprises 88% to 95% of HDPE and 5%-12% of LLDPE by weight, and/or that the LLDPE is metallocene LLDPE.

15. A blister packaging according to claim 1 characterised in that thermoformed web (30) further comprises an outer layer (32) comprising HDPE as the main ingredient.

16. A packaged pharmaceutical or nutritional product, comprising a blister packaging according to claim 1, and a pharmaceutical or nutritional product (40) in solid form contained in the cavities.

17. A method for producing a packaged product according to claim 16, said method comprising the following steps: preheating a web material comprising at least two co-extruded layers: a main layer comprising HDPE and up to 2% of a first additive, and a sealing layer comprising HDPE and at most 50% of LLDPE thermoforming the web material to form a web with cavities therein, introducing a pharmaceutical or nutritional product in solid form into each cavity, preheating a lid material comprising at least three co-extruded layers: an outer HDPE layer containing up to 5% of a second additive, an intermediate HDPE layer comprising an additive suitable to decrease elongation at break, and an inner sealing layer, sealing the inner sealing layer of the lid on the sealing layer of the web between the cavities using a heated sealing roll, and cutting the resulting product into blister packaging of a desired format.

18. A method according to claim 17, wherein the first additive in the main layer of the web material is an inorganic additive.

19. A method according to claim 17, wherein the second additive in the outer HDPE layer of the lid is an inorganic additive.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0068] FIG. 1 shows a perspective view of a blister packaging according to the invention containing a product in some cavities,

[0069] FIG. 2 shows a schematic cross-sectional view of the layered structure of a blister packaging according to the invention.

[0070] FIG. 3 shows a perspective view of the blister packaging of FIG. 1 after a product has been removed from a cavity.

[0071] FIG. 4 shows a schematic view of a production line where a packaged pharmaceutical or nutritional product according to the invention is produced.

DETAILED DESCRIPTION

[0072] Embodiments described herein can be understood more readily by reference to the following detailed description, examples, and figures. Elements, devices, and methods described herein, however, are not limited to the specific embodiments presented in the detailed description, examples, and figures. It should be recognized that the exemplary embodiments herein are merely illustrative of the principles of the disclosed invention. Numerous modifications and adaptations will be readily apparent to those of skill in the art without departing from the spirit and scope of the invention.

[0073] In addition, all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, a stated range of 1.0 to 10.0 should be considered to include any and all subranges beginning with a minimum value of 1.0 or more and ending with a maximum value of 10.0 or less, e.g., 1.0 to 5.3, or 4.7 to 10.0, or 3.6 to 7.9.

[0074] All ranges disclosed herein are also to be considered to include the end points of the range, unless expressly stated otherwise. For example, a range of between 5 and 10 or 5 to 10 or 5-10 should generally be considered to include the end points 5 and 10.

[0075] Where only a maximum amount for an ingredient is disclosed, this should be understood as encompassing all amounts above 0 which are detectable and which the person skilled in the art would consider has having a technical effect.

[0076] FIG. 1 shows a perspective view of an exemplary blister packaging 1 with a thermoformed web with cavities 10 formed therein, and a lid 20 sealed on the web 30. The sealing between the lid and the web 30 bonds the lid 20 and web 30 together over the complete contact surface between the lid 20 and the web 30, i.e. everywhere except where cavities 10 are formed.

[0077] FIG. 2 shows a schematic cross-sectional view of a multilayered structure present in the blister packaging 1 of FIG. 1 between the cavities 10. The multilayered structure comprises a lid 20 with three layers 22, 24 and 26 sealed onto a web with three layers 32, 34 and 36.

[0078] The different layers correspond, from top to bottom, to an outer layer 22, an intermediate layer 24, and a sealing layer 26 for the lid, and then a sealing layer 36, a main layer 34, and an outer layer 32 for the web.

[0079] Examples for suitable layer structures are given below. Tables 1 and 3 give examples of suitable layer structures for a lid 20, whereas tables 2 and 4 give examples for suitable layer structures for a web 30. The example lid structures given in tables 1 and 3 can both be combined with each of the example web structures given in tables 2 and 4, i.e. the lid structure of table 1 can be used with the web structure of table 2 or with the web structure of table 4, and the lid structure of table 3 can be used with the web structure of table 2 or with the web structure of table 4.

TABLE-US-00001 TABLE 1 Example layer structure for a lid Example % by weight Thickness component within Layer [microns] Component(s) (trade name) layer Outer 20 HDPE Lyondell basell 99.5% layer CaCO.sub.3 Alathon M6020SB 0.5% Intermediate 65 HDPE Lyondell basell 95.00 layer Alathon M6020SB Talc Imerys Luzenac? 5.00 R-7 Talc Sealing 15 EVA 28% Dow Elvax 265 99.60 layer Slip agent Crodamide ER 0.40

TABLE-US-00002 TABLE 2 Example layer structure for a web Example % by weight Thickness component within Layer [microns] Component(s) (trade name) layer Sealing 20 HDPE HDPE Sabic PCG0863 90.00 layer mLLDPE Sabic Supeer 8318 10.00 Main 210 HDPE Lyondell basell 99.50 layer Alathon M6020SB Talc Imerys Luzenac? 0.50 R-7 Talc Outer 20 HDPE Lyondell basell 100.00 layer Alathon M6020SB

TABLE-US-00003 TABLE 3 Example layer structure for a lid Example % by weight Thickness component within Layer [microns] Component(s) (trade name) layer Outer 20 HDPE Lyondell basell 99.5% layer CaCO.sub.3 Alathon M6020SB 0.5% Intermediate 50 HDPE Lyondell basell 97.00 layer Alathon M6020SB Nucleating Milliken 3.00 agent HYPERFORM? HPN-20E Sealing 10 EVA 28% Dow Elvax 265 99.60 layer Slip agent Crodamide ER 0.40

TABLE-US-00004 TABLE 4 Example layer structure for a web Example % by weight Thickness component within Layer [microns] Component(s) (trade name) layer Sealing 20 HDPE HDPE Sabic PCG0863 50.00 layer mLLDPE Sabic Supeer 8318 50.00 Main 210 HDPE Lyondell basell 98.00 layer Alathon M6020SB Nucleating Milliken 2.00 agent HYPERFORM? HPN-20E Outer 20 HDPE Lyondell basell 100.00 layer Alathon M6020SB

[0080] In the example of table 1 above, the lid 20 consists of a HDPE outer layer 22 with a thickness of 20 ?m which contains 0.5% of CaCO.sub.3, an intermediate layer 24 with a thickness of 65 ?m which contains 95% HDPE and 5% of talc, and a sealing layer 26 with a thickness of 15 ?m which contains 99.6% of EVA 28%, i.e. ethylene-vinyl acetate (EVA) with 28% of vinyl acetate content, and 0.4% of an amide serving as a slip agent. In the example of table 3, the talc in the intermediate layer 24 is replaced by 3% of a nucleating agent.

[0081] In the case of the example in table 1, the addition of 5% talc to the HDPE in the intermediate layer 24 decreases elongation at break. The same accounts for the addition of 0.5% CaCO.sub.3 to the outer layer 22, and, in the case of the example of table 3, for the addition of 3% of a nucleating agent to the HDPE in the intermediate layer. The resulting elongation at break is below 10% for the complete lid 20 with the structure as given in table 1 and also for the lid with the structure as given in table 3, depending on direction measurement for the lid material, resulting in an opening force that is at the level which is desired for CRSF certification.

[0082] In the example of table 2, the web 30 comprises a sealing layer 36 with a thickness of 20 ?m and having 90% of HDPE and 10% of metallocene LLDPE to improve adhesion, an HDPE main layer having 99.5% of HDPE with 0.5% of talc and an HDPE only outer layer with a thickness of 20 ?m.

[0083] In the example of table 2, the material chosen for the main layer 34 may also contain an optional nucleating agent which further improves the moisture barrier.

[0084] In the example of table 4, the web 30 comprises a sealing layer 36 with again a thickness of 20 ?m, but having 50% of HDPE and 50% of metallocene LLDPE leading to a further improved adhesion as compared to the example for a web of table 2, without leading to sticking issues in manufacturing. Furthermore, the main layer of the example of table 4 has 98% of HDPE and 2% of nucleating agent, namely Milliken HYPERFORM? HPN-20E, which is a 1,2-Cyclohexanedicarboxylic acid, calcium salt:zinc stearate. The main layer has a thickness of 210 ?m. The outer layer is again an HDPE only layer with a thickness of 20 ?m.

[0085] As already mentioned above, additional oxygen barrier layers can be included in or on top of the lid 20 or the web 30 in some embodiments. For the web 30, an EVOH layer (typically in between two bonding layers, also called tie layers) is preferred, because EVOH barrier properties are not altered during thermoforming. For the lid 20, an EVOH layer can also be used in some instances, but coatings providing an oxygen barrier are a suitable alternative in some cases.

[0086] FIG. 3 illustrates the reaction of the lid 20 when an adult presses on the blister packaging 1 to remove a tablet from the blister. The lid 20 ruptures around the cavity 10, thereby creating an opening through which the tablet can be removed, while leaving all other cavities still covered by the lid material 20, and the sealing between the lid 20 and the web 30 intact.

[0087] In another aspect, a method for producing a blister packaging according to the invention containing a product is now described with reference to FIG. 4.

[0088] A web film 30 with a thickness of 250 ?m is unwound using an unwinder 100, and then pre-heated between two plates at 125? C. at pre-heating station 102 before being thermoformed at a temperature of 130? C. in a thermoforming unit 104. The thermoforming unit 104 is a blister machine from Industria Macchine Automatiche S.P.A. (IMA) designed to produce conventional polyvinyl chloride (PVC) blisters with lid foil of type C80. The line speed can be set up at 250 blisters per minute. After the thermoforming step, the thermoformed web is cooled (not shown in FIG. 4), and a tablet feeder 106 feeds tablets 40 into the cavities 10. A second unwinder 108 unwinds a lid film 20 with 100 ?m thickness. The lid film 20 is then pre-heated at the pre-heater roll 110 at a temperature of 110? C. and heat sealed onto the thermoformed web 30 at 140? C. and a pressure of 5 bar pressure using a heat sealing roll 112 and a cooled format roll 114. The direct contact heat seal established a sealing connection between the sealing layer 26 of the lid film 20, and the sealing layer 36 of the thermoformed web film 30. At this sealing step, the lid film 20 and the thermoformed web film 30 are in between a first face of a direct contact heat sealer, namely the heated sealing roll 112, and an opposing second face of direct contact heat sealer, namely the cooled format roll 114. The heated sealing roll 112 makes physical contact with the outer layer 22 of the lid 20, and the cooled format roll 114 makes physical contact with the outer layer 32 of the web 30. Heat and pressure are applied by the heated sealing roll 112, over a defined period of time, to impart the direct contact heat seal between the two films 20,30. The cooled format roll 114 causes a cooldown to a temperature of below 25? C., for example around 12? C., to limit deformation due to plastic behaviour of the thermoformed blister web 30. The cooled format roll 114 is carved out to match the shape of the thermoformed blister in order to obtain a direct contact on the whole surface of the thermoformed cavity.

[0089] The combination of thermoformed web 30 with the tablets 40 in the cavities and the lid 20 sealed onto the web 30, can be embossed or printed at this stage to mark variable data, such as a lot number, expiry date, or manufacturing site. The blister is then punched or cut at a cutting station 116 and prepared for packaging.

[0090] The heat seal between the thermoformed web 30 and the lid 20 is of sufficient quality to pass leak tests where the complete blister packaging 1 is placed into a vacuum container under 2 bar of depression which has been filled with methylene blue dye mixed with water for a time of 2 minutes.