Barrier film comprising microfibrillated cellulose and microfibrillated dialdehyde cellulose and a method for manufacturing the barrier film

Patent metadata

Field	Value
Publication number	US-11162222-B2
Application number	US-201816604489-A
Country	US
Kind code	B2
Filing date	Apr 11, 2018
Priority date	Apr 12, 2017
Publication date	Nov 2, 2021
Grant date	Nov 2, 2021

Abstract

The present invention relates to a method for manufacturing at least one layer of a film wherein the method comprises the steps of; providing a first suspension comprising microfibrillated cellulose, providing a second suspension comprising microfibrillated dialdehyde cellulose, mixing the first suspension with the second suspension to form a mixture, applying said mixture to a substrate to form a fibrous web and drying said web to form at least one layer of said film. The present invention further relates to a film comprising said at least one layer.

First claim

The invention claimed is:

1. A film comprising microfibrillated cellulose wherein the film has an oxygen transmission rate in the range of from 0.1 to 300 cc/m 2 /24h measured according to ASTM D-3985, at a relative humidity of 50% at 23° C. and/or at a relative humidity of 90% at 38° C., and wherein at least one layer of the film comprises a mixture of microfibrillated cellulose and microfibrillated dialdehyde cellulose.

2. The film as claimed in claim 1 , wherein the film has a basis weight of less than 50 g/m 2 .

3. The film as claimed in claim 1 , wherein said film is a multilayer film comprising more than one layer.

4. The film as claimed in claim 1 , wherein said film is a multilayer film and wherein at least one layer of the film is a water vapor barrier film comprising any one of polyethylene (PE), polypropylene (PP), polyamide, polyethylene terephthalate (PET) or ethylene vinyl alcohol (EVOH).

5. The film according to claim 4 , wherein the water vapor barrier film has a grammage between 10-60 g/m 2 .

6. The film according to claim 1 , wherein said film is a multilayer film and wherein at least one layer of the film is a metallized barrier layer.

7. The film according to claim 6 , wherein said metallized barrier layer is a physical vapour deposited metal or metal oxide layer, or a chemical vapour deposited metal or metal oxide layer.

8. The film according to claim 7 , wherein said metal or metal oxide is selected from the group consisting of aluminium, aluminium oxides, magnesium oxides, silicium oxides, copper, magnesium and silicon.

9. The film according to claim 6 , wherein said metallized barrier layer has a weight between 50-250 mg/m 2 .

10. A packaging material comprising a base material and at least one layer of the film as claimed in claim 1 .

11. The packaging material according to claim 10 , wherein the base material is paper or paperboard.

12. The packaging material according to claim 11 , wherein the paper or paperboard has a grammage between 20-500 g/m 2 .

13. The packaging material according to claim 11 , wherein the paper or paperboard has a grammage between 80-400 g/m 2 .

14. The film as claimed in claim 1 , wherein the film has a basis weight of between 10-50 g/m 2 .

15. The film according to claim 4 , wherein the water vapor barrier film has a grammage between 30-50 g/m 2 .

16. The film according to claim 6 , wherein said metallized barrier layer has a weight between 75-150 mg/m 2 .

Assignees

• Stora Enso Oyj

Inventors

• Land Hensdal Cecilia
• Svensson Adrianna
• Bergqvist Liv
• Tran Carlström Amy
• Axrup Lars

Classifications

• B32B27/32

  comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} · CPC title

• B32B2307/7246

  Water vapor barrier · CPC title

• B32B2307/31

  Heat sealable · CPC title

• B32B2255/10

  on synthetic resin layer or on natural or synthetic rubber layer · CPC title

• C08B15/02

  Oxycellulose; Hydrocellulose; {Cellulosehydrate, e.g. microcrystalline cellulose} · CPC title