Metallized multi-layer films, methods of manufacture and articles made therefrom

Abstract

Multi-layer films particularly suited for packaging applications, including a core layer, a seal layer located on one side of the core layer, the seal layer comprising a polyolefin polymer and a silicone gum and a metallized layer located on the opposite side of the core layer from the seal layer are provided. Optionally, the multi-layer film may have a first tie layer located intermediate the core layer and the seal layer and/or a second tie layer located intermediate the core layer and the metallized layer. Embodiments may have the desirable combination of improved metal adhesion and slip properties.

Description

Claims

1. A metallized multi-layer film, comprising: (a) a core layer;(b) a seal layer located on a side of said core layer, said seal layer comprising a polyolefin polymer and a silicone gum, the silicone gum having a viscosity of at least 2 million centistokes at 25° C., wherein the outermost surface of said seal layer has a coefficient of friction less than about 0.4; and(c) a metallized layer located on a side of said core layer opposite said seal layer.

2. The metallized multi-layer film of claim 1, wherein said core layer comprises at least one polymer selected from the group consisting of polypropylene homopolymer, isotactic polypropylene homopolymer, high density polyethylene, high crystalline polypropylene and combinations thereof.

3. The metallized multi-layer film of claim 2, wherein said core layer further comprises a cavitating agent selected from the group consisting of cyclo-olefin polymers and copolymers, polybutylene terephthalate, nylon, solid glass spheres, hollow glass spheres, metal beads or spheres, ceramic spheres, calcium carbonate, talc, chalk and combinations thereof.

4. The metallized multi-layer film of claim 1, wherein said core layer has a thickness in the range of from about 10 microns to about 48 microns.

5. The metallized multi-layer film of claim 1, wherein said core layer has a thickness in the range of from about 13 microns to about 33 microns.

6. The metallized multi-layer film of claim 1, wherein said polyolefin polymer of said seal layer is selected from the group consisting of ethylene-propylene random copolymer, propylene-ethylene random copolymer, propylene-butylene random copolymer, ethylene-propylene-butylene terpolymers, polypropylene plastomers, polyethylene plastomers, and combinations thereof.

7. The multi-layer film of claim 1, wherein said silicone gum has a viscosity greater than 10 million centistokes at 25° C.

8. The multi-layer film of claim 1, wherein said silicone gum has a viscosity greater than 20 million centistokes at 25° C.

9. The metallized multi-layer film of claim 1, wherein said seal layer comprises from about 0.1 wt % to about 2.0 wt % silicone gum.

10. The metallized multi-layer film of claim 1, wherein said seal layer has a thickness in the range of from about 0.5 microns to about 8.0 microns.

11. The metallized multi-layer film of claim 1, wherein said metallized layer comprises at least one polymer selected from the group consisting of ethylene-propylene random copolymer, butylene copolymer, propylene-butylene random copolymer, an ethylene-propylene-butylene terpolymer, high density polyethylene, ethylene vinyl alcohol copolymer, and combinations thereof.

12. The metallized multi-layer film of claim 1, wherein said metallized layer has a thickness in the range of from about 0.2 microns to about 2.0 microns.

13. The metallized multi-layer film of claim 1, wherein said metallized layer has a thickness in the range of from about 0.5 microns to about 1.0 microns.

14. The metallized multi-layer film of claim 1, wherein said metallized layer is treated on the outermost surface with at least one of flame, plasma, corona discharge or polarized flame prior to metallization.

15. The metallized multi-layer film of claim 14, wherein the outermost surface of the metallized layer is vacuum metallized with at least one metal selected from the group consisting of aluminum, gold, silver, chromium, tin, copper and combinations thereof.

16. The metallized multi-layer film of claim 1, wherein said film has a water vapor transmission rate less than 0.5 g/m2/24 hours.

17. The metallized multi-layer film of claim 1, wherein said film has an oxygen transmission rate less than 100 cc/m2/24 hours.

18. The metallized multi-layer film of claim 1, wherein said film has an optical density greater than 2.0.

19. The metallized multi-layer film of claim 1, wherein said film has a tensile modulus of at least 2200 N/mm2.

20. The metallized multi-layer film of claim 1, further comprising at least one of (a) a first tie layer located intermediate said core layer and said seal layer, and (b) a second tie layer located intermediate said core layer and said metallized layer.

21. The metallized multi-layer film of claim 20, wherein at least one of said first tie layer and said second tie layer comprises at least one polymer selected from the group consisting of polypropylene homopolymer, isotactic polypropylene homopolymer, high density polyethylene and combinations thereof.

22. The metallized multi-layer film of claim 20, wherein at least one of said first tie layer and said second tie layer comprise at least one opacifying agent selected from the group consisting of iron oxide, carbon black, aluminum, titanium dioxide, calcium carbonate, polybutylene terephthalate, talc, beta nucleating agents and combinations thereof.

23. A metallized multi-layer film comprising: (a) a core layer;(b) a seal layer located on a side of said core layer, said seal layer comprising a polyolefin polymer and a silicone gum, the silicone gum having a viscosity of at least 2 million centistokes at 25° C., wherein said outermost surface of said seal layer has a coefficient of friction less than about 0.4;(c) a metallized layer located on a side of said core layer opposite said seal layer; and(d) a first tie layer intermediate to said core layer and said seal layer.

24. A metallized multi-layer film comprising: (a) a core layer;(b) a seal layer located on a side of said core layer, said seal layer comprising a polyolefin polymer and a silicone gum, the silicone gum having a viscosity of at least 2 million centistokes at 25° C., wherein said outermost surface of said seal layer has a coefficient of friction less than about 0.4;(c) a metallized layer located on a side of said core layer opposite said seal layer;(d) a first tie layer intermediate to said core layer and said seal layer; and(e) a second tie layer intermediate to said core layer and said metallized layer.

25. A method for producing a metallized multi-layer film comprising the steps of: (a) forming a multi-layer film, wherein said film comprises, (i) a core layer;(ii) a seal layer located on a side of said core layer, said seal layer comprising a polyolefin polymer and a silicone gum, the silicone gum having a viscosity of at least 2 million centistokes at 25° C., wherein said outermost surface of said seal layer has a coefficient of friction less than about 0.4; and(iii) a metallized layer located on a side of said core layer opposite said seal layer,(b) treating the outermost surface of said metallized layer with at least one of flame, plasma, corona discharge or polarized flame prior to metallization, and(c) metallizing the outermost surface of said metallized layer with at least one vacuum deposited metal selected from the group consisting of aluminum, gold, silver, chromium, tin, copper and combinations thereof.

26. The method of claim 25, wherein said silicone gum has a viscosity greater than 10 million centistokes at 25° C.

27. The method of claim 25, wherein said silicone gum has a viscosity greater than 20 million centistokes at 25° C.

28. The method of claim 25, wherein said seal layer comprises 0.1 wt % to 2.0 wt % silicone gum.

29. The method of claim 25, wherein said metallized multi-layer film has a water vapor transmission rate less than about 0.5 g/m2/24 hours.

30. The method of claim 25, wherein said metallized multi-layer film has an oxygen transmission rate less than about 100 cc/m2/24 hours.

31. The method of claim 25, wherein said metallized multi-layer film has an optical density greater than about 2.0.

32. A metallized multi-layer film produced according to the method of claim 25.

33. A package comprising a metallized multi-layer film comprising: (a) a core layer;(b) a seal layer located on a side of said core layer, said seal layer comprising a polyolefin polymer and a silicone gum, the silicone gum having a viscosity of at least 2 million centistokes at 25° C., wherein said outermost surface of said seal layer has a coefficient of friction less than about 0.4; and(c) a metallized layer located on a side of said core layer opposite said seal layer,said metallized multi-layer film being formed into a package adapted to contain a product.