Abstract
A cover film (1) for sealing a base film (2) of a blister pack for drugs, comprising two outer layers, namely, a cover layer (3) and a sealing layer (4), and one or more intermediate layers (5) situated between the cover layer (3) and the sealing layer (4), characterized in that the cover layer (3) and the sealing layer (4) are polypropylene layers (6, 7, 10).
Claims
1.-16. (canceled)
17. A blister pack for drugs that includes a cover film (1), wherein the cover film (1) comprises: two outer layers, namely, a cover layer (3) and a sealing layer (4), and one or more intermediate layers (5) situated between the cover layer (3) and the sealing layer (4), characterized in that the cover layer (3) and the sealing layer (4) are polypropylene layers (6, 7, 10).
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] In the figures:
[0029] FIG. 1: shows a schematic illustration of a multilayer film according to the invention,
[0030] FIG. 2: shows a first exemplary embodiment of the multilayer cover film according to the invention,
[0031] FIG. 3: shows a second exemplary embodiment of the multilayer cover film according to the invention,
[0032] FIG. 4: shows a third exemplary embodiment of the multilayer cover film according to the invention, and
[0033] FIG. 5: shows a fourth exemplary embodiment of the multilayer cover film according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] FIG. 1 shows a schematic illustration of a multilayer film according to the invention. The cover film 1 and the base film 2 are each made up of two outer layers, namely, a cover layer 3 and a sealing layer 4. The cover layer 3 is the side of the cover film 1 that faces the outside or the surroundings. In contrast, the sealing layer 4 is the side of the cover film 1 that faces the drug within a cavity that is typically present in the base film 2. One or more intermediate layers 5 are situated between these outer layers, i.e., the cover layer 3 and the sealing layer 4.
[0035] FIG. 2 shows a first exemplary embodiment of the cover film 1 according to the invention. This cover film comprises two outer layers and one intermediate layer 5, the cover layer 3 and the sealing layer 4 being polypropylene homopolymer layers 6, and the intermediate layer 5 being a copolymer layer 7, in particular a heterophasic random copolymer layer. This cover film is suited for drugs that are less sensitive to water and oxygen, and is easy to press through due to the intermediate layer 5, which is much larger compared to the outer layers, since the intermediate layer 5 made of heterophasic random copolymer 7, compared to the polypropylene homopolymer layers 6, has greater brittleness or rigidity and thus less elasticity.
[0036] FIG. 3 shows a cover film 1 according to the invention that is also suitable for water-sensitive drugs. Between the two polypropylene homopolymer layers 6 as a cover layer 3 and a sealing layer 4, this cover film has a cycloolefin layer 8 as an intermediate layer 5.
[0037] To allow protection to be provided against both water and oxygen, in addition a corresponding cover film is shown in FIG. 4. This cover film likewise includes a polypropylene homopolymer layer 6 in each case as a cover layer 3 and a sealing layer 4, and a total of three intermediate layers 5. The first two intermediate layers 5, which directly adjoin the outer layers, i.e., the cover layer 3 and the sealing layer 4, are a cycloolefin layer 8 in each case. Lastly, situated between the two cycloolefin layers 8 is a polyvinyl alcohol layer 9, which due to its material properties has a high oxygen affinity. The cover film 1 shown here in FIG. 4 thus has a high water vapor barrier and oxygen barrier.
[0038] Lastly, FIG. 5 shows a cover film 1 according to the invention in which the two outer layers, i.e., the cover layer 3 and the sealing layer 4, are nucleated polypropylene homopolymer layers 10, and the cover film has three intermediate layers 5. Here as well, the two outer layers are adjoined in each case by a cycloolefin layer 8, both of which enclose a heterophasic random copolymer layer 7.
[0039] Thus, a cover film for a blister pack as well as a blister pack for drugs are described above, by means of which aluminum may be dispensed with in the film, and the requirements for a high water vapor barrier and oxygen barrier may be met in a cost-effective manner.
LIST OF REFERENCE NUMBERS
[0040] 1 cover film [0041] 2 base film [0042] 3 cover layer [0043] 4 sealing layer [0044] 5 intermediate layer [0045] 6 polypropylene homopolymer layer [0046] 7 copolymer layer [0047] 8 cycloolefin layer [0048] 9 polyvinyl alcohol layer [0049] 10 nucleated polypropylene homopolymer layer
