A package is formed a closed bag made of a multilayer film and contents enclosed in the bag. The film is folded to form the bag and has flat film sides and outer edges that are reinforced by weld seams. The film of the bag has a density of 0.5 g/cm 3 to 0.9 g/cm 3 , a printable outer layer forming an outside surface of the package, an inner seal layer made of a sealable polymer forming an inside surface of the package, and a foamed polymer core layer between the outer layer and the inner layer. The contents are a lumpy or granular bulk material.
1. A package comprising a closed bag made of a multilayer film and contents enclosed in the bag, wherein the bag is formed by folding the film and has an outer shape defined by the folded film, flat film sides, and outer edges that are reinforced by weld seams, the film of the bag having
a density of 0.5 g/cm 3 to 0.9 g/cm 3 and a printable outer layer forming an outside surface of the package,
an inner seal layer made of a sealable polymer forming an inside surface of the package, and
a foamed polymer core layer between the outer layer and the inner layer, the contents being a lumpy or granular bulk material.
2. The package according to claim 1 , wherein the contents is chunk-type, pelletized, or granular dry food for animals.
3. The package according to claim 1 , wherein the contents is chunk-type food products.
4. The package according to claim 1 , wherein the film has a mass per unit surface area of between 30 g/m 2 and 150 g/m 2 .
5. The package according to claim 1 , wherein the foamed polymer core layer has a microcellular structure generated by physical foaming.
6. The package according to claim 1 , wherein the outer layer is applied to a multilayer polyethylene film that has a foamed polymer core layer, and unfoamed polyethylene layers on both sides of the core layer.
7. The package according to claim 6 , wherein the multilayer polyethylene film is made of PE-LD, PE-LLD, or a mixture of PE-LD and PE-LLD, and has a density of between 0.6 g/cm 3 and 0.8 g/cm 3 .
8. The package according to claim 1 , wherein the polymer of the foamed polymer core layer contains inorganic nucleating agents.
9. The package according to claim 1 , wherein the foamed polymer core layer has a layer thickness of 20 μm to 200 μm.
10. The package according to claim 1 , wherein the outer layer is made of polyester, BOPP, or a polyolefin.
11. The package according to claim 1 , further comprising:
a barrier layer made of a metallized polymer between the outer layer and the foamed polymer core layer.