Biobased barrier film for packaging material
AssigneeStora Enso OYJ
InventorsIsto Heiskanen, Kaj Backfolk, Katja Lyytikäinen
Life of this patent
Estimating the term…
Abstract
The present invention relates to a biobased barrier film for a paper or paperboard-based packaging material, said barrier film comprising: a substrate layer and a coating layer disposed on at least one surface of the substrate layer, wherein said substrate layer has a grammage in the range of 1-60 g/m2 and comprises at least 50 wt % of highly refined cellulose pulp based on the dry weight of the substrate layer, and wherein said coating layer has a grammage in the range of 1-15 g/m2 and comprises at least 50 wt % of a film forming modified starch and 0.1-10 wt % of a biobased lubricant, based on the dry weight of the coating layer.
Claims18
A biobased barrier film for a paper or paperboard-based packaging material, said barrier film comprising:
- a substrate layer;
- and
- a coating layer disposed on at least one surface of the substrate layer,
- wherein said substrate layer has a grammage in a range of 1-60 g/m2 and comprises at least 50 wt %, based on a dry weight of the substrate layer, of highly refined cellulose pulp having a Schopper-Riegler (SR) number above 70, as determined by standard ISO 5267-1, and
- wherein said coating layer has a grammage in a range of 1-15 g/m2 and comprises at least 50 wt % of a film forming modified starch and 0.1-10 wt % of a biobased lubricant, based on a dry weight of the coating layer.
A method for manufacturing a barrier film for a paper or paperboard based packaging material, comprising the steps of:
- a) providing a substrate layer, wherein said substrate layer has a grammage in a range of 1-60 g/m2 and comprises at least 50 wt %, based on a dry weight of the substrate layer, of highly refined cellulose pulp having a Schopper-Riegler (SR) number above 70, as determined by standard ISO 5267-1;
- b) applying an aqueous coating composition on at least one surface of the substrate layer, wherein said aqueous coating composition comprises at least 50 wt % of a film forming modified starch and 0.1-10 wt % of a biobased lubricant, based on a dry weight of the aqueous coating composition;
- and
- c) drying the aqueous coating composition to obtain a coating layer disposed on the at least one surface of the substrate layer, wherein said coating layer has a grammage in a range of 1-15 g/m2.
Dependencies are inferred from the claim text.