Container for foodstuff made from an aluminium-free planar composite with a covered hole as part of a closure system
A planar composite for the production of a container surrounding an interior having a. a carrier layer; b. a barrier layer of plastic joined to the carrier layer; c. at least two layers of thermoplastic plastic which are provided on the side of the barrier layer of plastic facing away from the carrier layer. The carrier layer has at least one hole which is covered by the barrier layer of plastic and the at least two layers of thermoplastic plastic. The composite is useful for the production of a container. Also disclosed is a process for the production of a container using the composite and a container obtainable by this process.
1. A planar composite for the production of a container surrounding an interior, comprising
a. a carrier layer;
b. a barrier layer of plastic joined to the carrier layer; and
c. at least two layers of thermoplastic plastic are provided on the side of the barrier layer of plastic facing away from the carrier layer, wherein at least one of the at least two layers of plastic is a plastics mixture of at least two plastics;
wherein the carrier layer has at least one hole;
wherein the at least one hole is covered by the barrier layer of plastic and the at least two layers of thermoplastic plastic as hole-covering layers, wherein no metal foil is provided between the carrier layer and the at least two layers of thermoplastic plastic.
2. The composite according to claim 1 , wherein at least one of the at least two layers of thermoplastic plastic has a melting temperature below the melting temperature of the barrier layer of plastic.
3. The composite according to claim 1 , wherein the at least two layers of thermoplastic plastic have a melting temperature in the range of from 80 to 155° C.
4. The composite according to claim 1 , wherein at least one of the at least two layers of thermoplastic plastic is filled with a particulate inorganic solid.
5. The composite according to claim 1 , wherein the at least two layers of thermoplastic plastic are made of a polyethylene or a polypropylene or a mixture of at least two of these.
6. The composite according to claim 5 , wherein the plastics mixture comprises a polyolefin prepared by means of a metallocene as one of at least two mixture components.
7. The composite according to claim 6 , wherein the plastic mixture comprises as one of the at least two mixture components 10 to 50 wt. %, based on the plastics mixture, of the polyolefin prepared by means of a metallocene.
8. The composite according to claim 6 , wherein the plastic mixture comprises as one of the at least two mixture components 50 to 95 wt, %, based on the plastics mixture, of the polyolefin prepared by means of a metallocene.
9. The composite according to claim 1 , wherein at least one further layer of thermoplastic plastic is joined to the carrier layer on the face of the carrier layer opposite the barrier layer.
10. The composite according to claim 9 , wherein the further layer of thermoplastic plastic comprises a polyethylene, a polypropylene or a mixture of these.
11. The composite according to claim 9 , wherein the at least one further layer of thermoplastic plastic has a melting temperature in a range of from 80 to 155° C.
12. The composite according to claim 9 , wherein the barrier layer of plastic has a melting temperature in a range of from more than 155 to 300° C.
13. The composite according to claim 9 , wherein the barrier layer of plastic is made of polyamide or polyethylene vinyl alcohol or a mixture thereof.
14. A container made from the composite according to claim 1 .
15. A process for the production of a container surrounding an interior, comprising the steps
α. providing a planar composite, comprising
a. a carrier layer;
b. a barrier layer of plastic joined to the carrier layer; and
c. at least two layers of thermoplastic plastic which are provided on the side of the barrier layer of plastic facing away from the carrier layer,
wherein at least one of the at least two layers of plastic is a plastics mixture of at least two plastics,
wherein the carrier layer has at least one hole, and
wherein the at least one hole is covered by the barrier layer of plastic and the at least two layers of thermoplastic plastic as hole-covering layers, wherein no metal foil is provided between the carrier layer and the at least two layers of thermoplastic plastic;
β. folding the planar composite to form a fold with at least two fold surfaces adjacent to one another; and
χ. joining respectively at least a part region of the at least two fold surfaces to form a container region.
16. The process according to claim 15 , wherein the composite is provided with the steps comprising
providing a carrier layer which has at least one hole; and
applying the barrier layer of plastic and the at least two layers of thermoplastic plastic to the carrier layer as hole-covering layers, wherein the at least one hole is covered by the hole-covering layers.
17. The process according to claim 15 , wherein at least one of the at least two layers of thermoplastic plastic in step β. is heated above the melting temperature thereof.
18. The process according to claim 15 , wherein at least one of the at least two layers of thermoplastic plastic in step β. is kept below the melting temperature thereof.
19. The process according to claim 15 , wherein the container is filled with a foodstuff before step β. or after step χ.
20. A container obtainable by the process according to claim 15 .