ROTARY CLOSURE WITH LINER FOR A CONTAINER

Abstract

The invention concerns a rotary closure especially for medication bottles, which has a rotary cap, in which a liner that closes the opening is provided. The liner has at least two layers, which contact each other along a contact surface; the upper layer initially lies in the rotary cap and is joined to it at least in the central part of the face and the lower layer is firmly joined to the annular face of the opening and the liner has a weakening line (4). In order to achieve simple and clean opening, it is prescribed that the weakening line (4) is closed and leads around the central part (3) of the face and that in the area of the contact surface within the weakening line (4) joining of the two layers is strong and outside the weakening line (4) it is not present or only weak.

Claims

1-8. (canceled)

9. A liner for a rotary closure, comprising: at least an upper multilayer and a lower multilayer joined to each other along a contact surface; wherein the liner incorporates a closed weakening line disposed around the contact surface, and the liner is configured so that along the contact surface the connection between the upper multilayer and the lower multilayer is strong, and outside the weakening line the connection between the upper multilayer and the lower multilayer is substantially weaker.

10. The liner of claim 9, wherein the upper multilayer is configured to be attached to at least a central part of a circular inner face of a rotary cap of the rotary closure; and the lower multilayer is configured to be firmly joined to an annular face of a container opening that can be sealed by the rotary cap.

11. The liner of claim 9, wherein the upper multilayer and the lower multilayer are joined to each other along the contact surface by an adhesive.

12. The liner of claim 9, wherein outside the weakening line there is no connection between the upper multilayer and the lower multilayer.

13. The liner of claim 9, including the following structure, listed from uppermost to lowermost: A) PET (polyethylene terephthalate); B) Glue; C) CPP film (unstretched polypropylene); D) Glue; E) Aluminum foil; F) Glue; and G) Sealing film.

14. The liner of claim 13, wherein the weakening line weakens the sealing film layer (G).

15. The liner of claim 14, wherein the contact surface lies within an area including the glue layer (F).

16. The liner of claim 14, wherein the weakening line also weakens the aluminum foil layer (E), and the contact surface lies within an area including the glue layer (D).

17. The liner of claim 9, wherein the weakening line is formed in the liner by a laser beam.

18. A container having a rotary closure; comprising: a rotary cap, wherein in an original closed state the rotary cap is screwed onto an annular face of an opening of the container; a liner that closes the opening of the container, the liner being disposed between a circular face of an inside of the rotary cap and the annular face of the opening; the liner having at least an upper multilayer and a lower multilayer joined to each other along a contact surface, the upper multilayer initially disposed within the rotary cap and attached to at least a central part of the circular face, and the lower multilayer firmly joined to the annular face of the opening; wherein the liner incorporates a closed weakening line disposed around the central part of the circular face, and the liner is configured so that along the contact surface the connection between the upper multilayer and the lower multilayer is strong, and outside the weakening line the connection between the upper multilayer and the lower multilayer is substantially weaker.

19. The container of claim 18, wherein the upper multilayer and the lower multilayer are independent of each other.

20. The container of claim 18, wherein the liner is configured so that the upper multilayer and the lower multilayer are joined to each other along the contact surface by an adhesive, and outside the weakening line there is no connection between the upper multilayer and the lower multilayer.

21. The container of claim 18, wherein the liner has a layered structure including, in order from the circular face of the inside of the rotary cat to the annular face of the container opening: A) PET (polyethylene terephthalate); B) Glue; C) CPP film (unstretched polypropylene); D) Glue; E) Aluminum foil; F) Glue; and G) Sealing film.

22. The container of claim 21, wherein the glue layer (F) is colored.

23. The container of claim 21, wherein the liner is configured so that the weakening line weakens the sealing film layer (G).

24. The container of claim 23, wherein the liner is configured so that the contact surface lies within an area including the glue layer (F).

25. The container of claim 23, wherein the liner is configured so that the weakening line also weakens the aluminum foil layer (E), and the contact surface lies within an area including the glue layer (D).

26. The container of claim 18, wherein the liner further includes a separation line disposed concentric with the weakening line and having a diameter that substantially corresponds to an inside diameter of the rotary cap.

27. The container of claim 18, wherein the lower multilayer is firmly joined to the annular face of the opening by induction sealing.

28. The container of claim 18, wherein the weakening line is formed in the liner by a laser beam.

29. The container of claim 18, wherein the container is a medication bottle.

Description

[0017] The invention is further described below by means of a practical example. The only FIGURE shows a schematic top view of a section from an endless material that already has the two layers in joined form.

[0018] The areas provided with adhesive between the two layers are drawn in this example with a dark color in the purely schematic (as stated) top view. Two areas are involved, which serve as markings 1 for positioning of the liner material 2 during production and assembly.

[0019] A central glue site 3 is arranged within a closed weakening line. The weakening line 4, as is preferred, has a circular shape, the center of the circle is as congruent as possible with the screw axis of the screw cap into which the liner is inserted. In this way undesired shear forces are avoided during first opening.

[0020] A separation line 5 is provided concentric to weakening line 4, which need not actually entail complete separation of the lower and/or upper layer, but which restricts the mechanical stability of the liner material 2 as a whole so that during introduction into the screw cap full separation of both layers occurs along this line and the liner broken out or punched out from the liner material 2 comes to lie on the interior of the screw cap and with the outer layer comes to lie on the inner face of the screw cap, covering its surface as much as possible, and is firmly and reliably glued or welded to it.

[0021] The area outside the separation line 5 does not enter the closure cap and does not belong to the closure and this part of the liner material 2 after introduction, of the litter into the screw cap is disposed of. The large-area annular glue site 6 outside the separation line 5 serves for precise fixation of the two layers relative to each other to obtain geometric correlation. Since no effect on the later liner occurs from areas outside the separation line 5, the glue surface here 6 can he modified in a variety of ways, for example. In several rings or a number of glue points and it is also possible to create additional glue sites in the areas that are the corner areas of the liner material 2 present as endless material in the FIGURE.

[0022] It is likewise possible to conduct gluing of both layers to be separated in the annular area between the weakening line 4 and the separation line 5, which, however, must be much weaker than the central glue surface 3, for example, in order not to compromise separation of the two layers during first opening.

[0023] The following can be mentioned as an example for the structure of such a closure, stated from the cap side (usually top) to the container side (usually bottom), in which this example of the structure is essentially simple and much more complex systems are known for the liner material in the prior art. The joint can be produced both by lamination and by extrusion or coextrusion and the adhesives, film materials and basis weights to be employed are then modified in ways known to one skilled in the art and with knowledge of the invention he therefore has no problems.

TABLE-US-00001 Example for thickness/ Cap inside basis weight A) PET (polyethylene 5-50 m terephthalate) B) Adhesive see below C) CPP film (unstretched 70-140 m polypropylene) (preferably around 100) D) Adhesive see below E) Aluminum foil 6-50 m (preferably around 30) F) Adhesive, optionally see below colored G) Sealing film 15-100 m Container edge

[0024] Instead of CPP, blown PP or orientated PP may be used with good results, too.

[0025] The glue is, for example, one- or two-component glue based on polyurethane and other peelable glues can also be used. The employed amounts, as known to one skilled in the art, can vary over a broad range and lie between 0.001 g/m.sup.2 and 5 g/m.sup.2.

[0026] Within weakening line 4 gluing of the layers must occur strongly tram the cap to the sealing film G, since all these layers A-G mast remain in this area on the cap. Outside the weakening line 4 gluing between the layers being separated, i.e., either glue layer F or D, is provided weakly or not at all, in order to permit separation along this contact surface.

[0027] As already mentioned above, it is possible to provide separation of the layers being separated in the area of glue layer D and glue in the area outside the weakening line 4 is then applied so sparsely that loosening can occur and not only the sealing film G but also the aluminum foil E in the area of weakening line 4 (preferably flush with it) need only be weakened so that during first opening the area within the weakening line 4 remains firmly joined to the cup and the weakening line tears off in the aluminum foil E.

[0028] This weakening line is to be applied from the side of the sealing film G which must be separated anyway and the aluminum foil on the one hand, must also be mechanically weakened in this case but, on the other hand, must completely fulfill its barrier property reliably in the area of the weakening line.

[0029] One thus obtains a partial joint remaining on the container, which contains in the surface outside the weakening line 4 (and the weakening line in the aluminum foil) the sealing film G and aluminum foil E, and therefore still has excellent barrier properties and high mechanical stability but entails some demands for this purpose in terms of accuracy of the weakening line, which must be formed through the sealing film G up to but in no case through the aluminum foil E.

[0030] If simpler production of the weakening line 4 is a primary concern, this is to be created from the later container side so that it causes the sealing film G to reliably rupture during first opening and can reach up to the aluminum foil E but not into it or only scarcely so; separation of the layers occurs in the area of glue layer F, which therefore is or contains the contact surface.

[0031] In a weakening line 4 designed in this way the aluminum foil E remains joined in its entirety to the cap and during first opening carries along the material of sealing film G placed within the weakening line. For this purpose the glue joint between the sealing layer and aluminum foil is designed strongly within the weakening line 4 but is weak or not present at all outside of it.

[0032] The weakening line may be created by any way known in the prior art, preferred by use of a laser beam, or a high energy ion beam, or by using a mechanical tool, e.g. a cutting tool. The man skilled in the art knows which technology to use when he or she takes into account the kind of container and the kind of goods.

[0033] The sealing of the liner to the container, namely the rim of the opening of the container, would in many cases be achieved by the use of induction sealing, with the heating of the aluminum foil by electro-magnetic waves, as it is known for such caps. Of course, the use of heat, provided by conductive heat transmission, without induction, and of pressure, as it is known since long time for all kinds of sealing purposes, may be used, too.

[0034] To summarize, one can state that the invention concerns a rotary closure for a container, like a bottle, especially a medication bottle or the like, which in the original closed state has a rotary cap that is screwed onto the opening of the container, in which case a liner that closes the opening is provided between the circular face of the inside of the rotary cap and the annular face of the opening, which has at least two multilayers independent of each other, which are in surface contact with each other along a contact surface, which optionally contains glue, in which case the upper layer initially lies in the rotary cap and is joined to it at least in the central area, of the face and in which the lower layer is firmly joined to the annular face of the opening and in which the liner has a weakening line 4, characterized by the fact that the weakening line 4 is closed and leads around the central part of the face and that in the area of the contact surface within the weakening line 4 joining of the two layers is strong and it is not present or only weak outside of the weakening line 4.

[0035] For jurisdictions, where it is possible, the contents of the CA 2,179,840, the DE 37 06 962, the EP 40 797, the EP 1 046 595, the EP 1 278 630, the EP 1 462 381, the EP 1 582 477, the FR 2 943 321, the U.S. Pat. No. 2,646,183, the U.S. Pat. No. 4,719,740, the WO 2012/079971, are, independently from each other, incorporated into the disclosure of this description by reference.

TABLE-US-00002 List of reference numbers: 01 Marking 02 Liner material 03 Central glue site 04 Weakening line 05 Separation line 06 Annular glue site