Multilayer barrier film, method for manufacturing multilayer barrier film, and paper or paperboard based packaging material comprising multilayer barrier film

Abstract

The present invention relates to a multilayer barrier film for a paper or paperboard packaging material, said barrier film comprises a first layer comprising a furnish comprising at least 70 wt-% of highly refined cellulose based on the total fiber content of the first layer, a second layer comprising a furnish comprising cellulosic fibers and less than 50 wt-% of highly refined cellulose based on the total fiber content of the second layer wherein the multilayer barrier film has an air permeance above 1000 pm/Pas and a tear index GM above 4.5. The present invention further relates to a paper and paperboard based packaging material comprising such multilayer barrier film and to methods for manufacturing such multilayer barrier film.

Dependencies are inferred from the claim text.