RECYCLABLE, COLLAPSIBLE TUBE WITH BARRIER PROPERTIES

Abstract

For recyclability in a high value circular recycling material stream, a fluid-tight collapsible polyolefin container comprises a container body (5) formed of a container laminate (1) that is folded to a container-like body, sealed in the overlapping edge regions (2, 3) and coated with a sheathing (4) of polyolefin material to form the container body (5), said container body (5) being provided at one open end with a container head formed from polyolefin material. The container laminate (1) is a laminate having at least three layers, an inner polyolefin layer (6) and an outer polyolefin layer (8) and a barrier layer (7) sandwiched between the outer polyolefin layer (8) and the inner polyolefin layer (6), wherein the barrier layer (7) comprises at least one polyolefin comprising barrier foil like a monolayer foil (71) or a coextruded foil (72 with layers 72a, 72b) or a laminate thereof and wherein at least 90% of all polymers of the container are made of polyolefin of the same kind.

Claims

1. A fluid-tight collapsible polyolefin container that comprises a container body formed of a container laminate, said container laminate being folded to a container-like body and sealed in the overlapping edge regions, said container-like body having an outer surface coated with a sheathing of polyolefin material to form the container body, said container body being provided at one open end with a shoulder/head formed from polyolefin material, wherein said container laminate is a laminate having at least three layers, an inner polyolefin layer and an outer polyolefin layer and a barrier layer sandwiched between the outer polyolefin layer and the inner polyolefin layer, wherein the barrier layer comprises at least one, optionally coextruded, polyolefin comprising oriented barrier foil and wherein at least 90% by weight of the container are made of polyolefin of the same kind.

2. The collapsible container of claim 1, wherein the polyolefin comprising oriented barrier foil is a polymeric coextruded foil.

3. The collapsible container of claim 2, wherein the polyolefin comprising oriented barrier foil is a mono-directional oriented polyethylene-ethylene vinyl alcohol copolymer (MDO-PE-EVOH) foil with an EVOH layer between two PE-layers, namely a PE—tie layer—EVOH—tie layer—PE foil.

4. The collapsible container of claim 2, wherein the polymeric coextruded barrier foil has a thickness in the range of 15 to 30 μm, in particular about 20 μm.

5. The collapsible container of claim 1, wherein the polyolefin comprising oriented barrier foil is an oriented polyolefin monolayer foil,

6. The collapsible container of claim 5, wherein the polyolefin comprising oriented barrier foil is a monolayer foil selected from a mono-directional oriented polyethylene (MDO-PE) foil or an oriented polypropylene (OPP) foil.

7. The collapsible container of claim 6 wherein the polyolefin monolayer foil, has a thickness in the range of 15 to 20 μm, such as 16 to 20 μm.

8. The collapsible container of claim 1, wherein the polyolefin comprising oriented barrier foil comprises at least one functional layer on at least one of its surfaces, said one or more functional layers being selected from the group consisting of metal layers and metal oxide or ceramic layers and layers of barrier lacquers and combinations of a barrier lacquer and a metal layer and combinations of a barrier lacquer and a metal oxide or ceramic layer.

9. The collapsible container of claim 8, wherein the one or more functional layers have a thickness of 5 to 100 nm, preferably 20-80 nm, in particular about 50 nm for metal or metal oxide or ceramic layers, and about 1 to 3 g/m.sup.2, preferably 1 to 2 g/m.sup.2 for cured barrier lacquer layers.

10. The collapsible container of claim 8, wherein the one or more metal layers are aluminium and/or the one or more metal oxide or ceramic layers are chosen from AlxOy and SiOx and/or the one or more layers of barrier lacquers are chosen from water insoluble polyvinyl alcohol based lacquers.

11. The collapsible container of claim 1, wherein the barrier layer is a barrier foil laminate of at least two independently selected polyolefin comprising and oriented barrier foils of the same or different kind, said oriented barrier foils being selected from polyolefin monolayer foils and polymeric coextruded foils and combinations thereof, said two barrier foils optionally comprising one or more functional layers on at least one of their surfaces so that the resulting laminate optionally comprises functional layers on at least one of its surfaces and/or one or more internal functional layer(s).

12. The collapsible container of claim 1, wherein the polyolefin is selected from polyethylene and polypropylene,

13. The collapsible container of claim 12, wherein the polyolefin is polyethylene selected from (i) HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE with at least 80% HDPE or mLLDPE or (ii) LLDPE or LDPE or HDPE/LLDPE or HDPE/LDPE with at most 30% HDPE.

14. The collapsible container of claim 1, wherein at least 95% by weight of the container are made of polyolefin of the same kind.

15. The collapsible container claim 1, wherein at least 90% by weight, preferably at least 95% by weight of the container laminate are made of polyolefin of the same kind.

16. The collapsible container of claim 1, wherein the inner polyolefin layer is a coextruded foil,

17. The collapsible container of claim 16, wherein the coextruded foil comprises an internal barrier layer.

18. The collapsible container of claim 17, wherein the coextruded foil comprises as internal barrier layer an EVOH layer, said coextruded foil in general being a PE—tie layer—EVOH—tie layer—PE foil.

19. The collapsible container of claim 1, wherein the outer polyolefin layer is a coextruded foil.

20. A container body for a collapsible container of claim 1 with a container laminate that is a laminate having at least three layers, an inner polyolefin layer and an outer polyolefin layer and a barrier layer sandwiched between the outer polyolefin layer and the inner polyolefin layer, wherein the barrier layer comprises at least one polyolefin comprising oriented barrier foil, said container body being provided with a sheathing of polyolefin, wherein at least 90% by weight, preferably at least 95% by weight of the container body are made of polyolefin of the same kind.

21. The container body for a collapsible container of claim 20, wherein the polyolefin is polyethylene selected from (i) HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE with at least 80% HDPE or mLLDPE or (ii) LLDPE or LDPE or HDPE/LLDPE or HDPE/LDPE with at most 30% HDPE.

22. A container laminate for a collapsible container of claim 1 that is a laminate having at least three layers, an inner polyolefin layer and an outer polyolefin layer and a barrier layer sandwiched between the outer polyolefin layer and the inner polyolefin layer, wherein the barrier layer comprises at least one polyolefin comprising and oriented barrier foil and wherein at least 90% of the container laminate are made of polyolefin of the same kind.

23. The container laminate for a collapsible container of claim 22, wherein the polyolefin is polyethylene selected from (i) HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE with at least 80% HDPE or mLLDPE or (ii) LLDPE or LDPE or HDPE/LLDPE or HDPE/LDPE with at most 30% HDPE.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0073] The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings showing schematic sectional view through a tube foil or tube laminate, respectively, formed from the indicated foils (from inside to outside with a slash indicating an adhesive layer) wherein:

[0074] FIG. 1 is an enlarged fragmentary sectional view of the container or tube body prior to the heading thereof, and wherein the thickness of the various layers of the tube have been exaggerated appreciably for the purpose of clarity and simplification in explanation of the invention.

[0075] FIG. 2 is PE/MDO-PE+metallization (or metal oxide or ceramic)/PE.

[0076] FIG. 3 is PE/MDO-PE+lacquer+metallization (or metal oxide or ceramic)/PE.

[0077] FIG. 4 is PE/MDO-PE-EVOH+metallization (or metal oxide or ceramic)/PE.

[0078] FIG. 5 is PE/MDO-PE-EVOH+lacquer+metallization (or metal oxide or ceramic layer)/PE.

[0079] FIG. 6 is PE/OPP+AlxOy/PE.

[0080] FIG. 7 is PE/OPP+metallization/PE.

[0081] FIG. 8 is PE/OPP+metallization (or metal oxide or ceramic)/OPP+metal oxide or ceramic (or metallization)/PE.

[0082] FIG. 9 is PE/OPP+metal oxide or ceramic/OPP+metallization/PE.

MODES FOR CARRYING OUT THE INVENTION

[0083] As indicated above, one subject matter of the present invention is a recyclable container, in particular a tube comprising a container, preferably a container body and most preferred a container laminate that is at least 90% PE or PP, in particular PE. Some presently preferred container laminates are shown in the Figures. In some embodiments the 90% polyolefins of one kind are only obtained for the container (laminate with sheathing and shoulder/head) or the container body (laminate with sheathing only).

[0084] FIG. 1 is an enlarged fragmentary sectional view of the container or tube body showing the seam section wherein overlapping edges 2 and 3 of the container laminate 1 are sealed and wherein the whole body, in particular also the seal are coated with a sheathing 4. The container laminate 1 is shown as three layer material with an inner polyolefin layer 6, an outer polyolefin layer 8 and a barrier layer 7 sandwiched between these two layers.

[0085] FIG. 2 shows a container laminate 1 with—from inside to outside—PE 6/adhesive 9/MDO-PE 71+metallization 10 or metal oxide or ceramic layer 11/adhesive 9/PE 8.

[0086] A presently preferred embodiment of the above material with a thickness of approx. 160 μm is composed as follows from inside PE (6) to outside PE (8):

[0087] For the flexible route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—20 μm MDO-PE with metallization—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm LDPE.

[0088] For the rigid route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—20 μm MDO-PE with metallization—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE.

[0089] FIG. 3 shows a laminate with—from inside to outside—PE 6/adhesive/MDO-PE 71+lacquer 12+metallization 10 or metal oxide or ceramic layer 11/PE 8.

[0090] A presently preferred embodiment of the above material with a thickness of approx. 160 μm is composed as follows:

[0091] For the flexible route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—20 μm MDO-PE with PVOH based barrier lacquer (approx. 1 g/m.sup.2) and optional metallization 10 or metal oxide or ceramic layer 11—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm LDPE.

[0092] For the rigid route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—20 μm MDO-PE with PVOH based barrier lacquer (approx. 1 g/m.sup.2) and optional metallization 10 or metal oxide or ceramic layer 11—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE.

[0093] FIG. 4 shows a laminate with—from inside to outside—PE 6/adhesive 9/MDO-PE-EVOH 72 (PE-layers 72a and EVOH layer 72b)+metallization 10 or metal oxide or ceramic layer 11/adhesive 9/PE 8.

[0094] A presently preferred embodiment of the above material with a thickness of approx. 160 μm is composed as follows:

[0095] For the flexible route:70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—20 μm MDO-PE-EVOH with optional metallization or metal oxide or ceramic layer—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm LDPE.

[0096] For the rigid route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—20 μm MDO-PE-EVOH with optional metallization or metal oxide or ceramic layer—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE.

[0097] FIG. 5 shows a laminate with—from inside to outside—PE 6/adhesive 9/MDO-PE-EVOH 72 (PE-layers 72a and EVOH layer 72b)+barrier lacquer 12+metallization 10 or metal oxide or ceramic layer 11/adhesive 9/PE 8.

[0098] A presently preferred embodiment of the above material with a thickness of approx. 160 μm is composed as follows:

[0099] For the flexible route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—20 μm MDO-PE-EVOH with barrier lacquer (approx. 1 g/m.sup.2) and with optional metallization 10 or metal oxide layer 11—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm LDPE.

[0100] For the rigid route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—20 μm MDO-PE-EVOH with barrier lacquer (approx. 1 g/m.sup.2) and with optional metallization 10 or metal oxide layer 11—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE.

[0101] In an alternative embodiment of FIG. 5 (not shown) the following sequence of the layers is present (from inside to outside): PE 6/adhesive 9/barrier lacquer 12 on MDO-PE-EVOH 72 (PE-layers 72a and EVOH layer 72b)+metallization 10 or metal oxide or ceramic layer 11/adhesive 9/PE 8.

[0102] FIG. 6 shows a laminate with—from inside to outside—PE 6/adhesive 9/OPP 71+metal oxide or ceramic 11/adhesive 9/PE 8.

[0103] A presently preferred embodiment of the above material with a thickness of approx. 160 μm is composed as follows:

[0104] For the flexible route:70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—15-20 μm, such as 16-20 μm OPP with AlxOy or SiOx—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm LDPE.

[0105] For the rigid route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—15-20 μm, such as 16-20 μm OPP with AlxOy or SiOx—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE.

[0106] FIG. 7 shows a laminate with—from inside to outside—PE 6/adhesive 9/OPP 71+metallization 10/adhesive 9/PE 8.

[0107] A presently preferred embodiment of the above material with a thickness of approx. 160 μm is composed as follows:

[0108] For the flexible route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—15-20 μm, such as 16-20 μm OPP—metallization—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm LDPE.

[0109] For the rigid route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—15-20 μm, such as 16-20 μm OPP—metallization—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—70 μm HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE.

[0110] FIG. 8 shows a laminate with a barrier layer that is a barrier foil laminate. In detail, FIG. 8 shows—from inside to outside: PE 6/adhesive 9/metallization 10 (or metal oxide or ceramic 11) on OPP 71/adhesive 9/OPP 71+metal oxide or ceramic 11 (or metallization 10)/adhesive 9/PE 8.

[0111] A presently preferred embodiment of the above material with a thickness of approx. 250 to 500 μm, such as 300 to 500 μm (comprising a LDPE sheathing) is composed as follows:

[0112] For the flexible route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—15-20 μm, such as 16-20 μm OPP with metallization (or AlxOy or SiOx)—SF polyurethane based adhesive (approx. 1 μm)—15-20 μm, such as 16-20 μm OPP with AlxOy or SiOx (or metallization)—SF adhesive (approx. 1.5 g/m.sup.2)—70 μm LDPE.

[0113] For the rigid route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—15-20 μm, such as 16-20 μm OPP with metallization (or AlxOy or SiOx)—SF polyurethane based adhesive (approx. 1 μm) −15-20 μm, such as −20 μm OPP with AlxOy or SiOx (or metallization)—SF adhesive (approx. 1.5 g/m.sup.2)—70 μm HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE.

[0114] FIG. 9 shows a laminate with—from inside to outside—PE 6/adhesive 9/OPP 71+metal oxide or ceramic 11/adhesive 9/OPP 71+metallization 10/adhesive 9/PE 8.

[0115] In one embodiment, the above material with a thickness of approx. 250 to 500 μm, such as 300 to 500 μm is composed as follows:

[0116] For the flexible route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—15-20 μm, such as 16-20 μm OPP+AlxOy—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—15-20 μm, such as 16-20 μm OPP with metallization—SF polyurethane based adhesive (approx. 1 μm)—70 μm LDPE.

[0117] For the rigid route: 70 μm HDPE/LLDPE or HDPE/LDPE—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—15-20 μm, such as 16-20 μm OPP+AlxOy—SF polyurethane based adhesive (approx. 1.5 g/m.sup.2)—15-20 μm, such as 16-20 μm OPP with metallization—SF polyurethane based adhesive (approx. 1 μm)—70 μm HDPE or mLLDPE or HDPE/LLDPE or HDPE/LDPE.

[0118] Independent of the specific laminates outlined above, in a preferred embodiment for the flexible route, the inner PE-foil 6 is of a mixture of HDPE/LLDPE or HDPE/LDPE, preferably in a ratio of 30% to 70%, and the outer PE-foil 8 is of LDPE.

[0119] In another preferred embodiment, for the rigid recycling route, the inner PE-foil 6 is of a mixture of HDPE/LLDPE, preferably in a ratio of ≥80% HDPE and ≤20% LLDPE, and the outer PE-foil 8 is of HDPE/LDPE, preferably in a ratio of ≥80% HDPE and ≤20% LDPE.

[0120] In yet another preferred embodiment, the inner PE-foil 6 is a barrier foil composed of PE/tie/EVOH/tie/PE with the PE for the rigid recycling route being HDPE or HDPE/LLDPE or HDPE/LDPE, preferably in a ratio of ≥80% HDPE and ≤20% LLDPE or ≥80% HDPE and ≤20% LDPE, and for the flexible recycling route the PE is LDPE, LLDPE or HDPE/LDPE or HDPE/LLDPE with at most 30 HDPE.

[0121] Such an inner foil is especially suited for containers comprising a content with compounds the migration of which has to be prevented since they might affect one of the further layers, especially the laminating adhesive. Also with such an inner foil the outer PE-foil 8 is as described above.

[0122] In another embodiment for the flexible recycling route both, the inner PE-foil 6 and the outer PE-foil 8 are of MDPE.

[0123] With regard to the barrier effect, a coextruded barrier foil is preferred, namely a highly oriented EVOH layer with small thickness (1-3 μm) within a MDO (mono-directionally oriented) PE foil.

[0124] The barrier effect of any of the polymeric barrier foils can be enhanced by applying at least one functional layer selected from a barrier lacquer, a metallization like Al and/or a metal oxide or ceramic thin film barrier like AlxOy or SiOx.

[0125] The adhesive layers can be the same or different but preferably are the same and much preferred are two-component polyurethane based and solvent-free or water based adhesives.

[0126] While there are shown and described presently preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.