Billerudkorsnas Ab

Jonas Almkvist

Constantinos Xenopoulos

Ove Lindström

Ove LINDSTRÖM

Ove Lindstrom

Daniel Söderström

Carina Leandersson

There is provided a method of making white sack paper having a grammage of 50-140 g/m2 and a Gurley porosity (ISO 5636/5) of 2-10 s, comprising the steps of: a) providing bleached pulp, such as bleached sulphate pulp; b) subjecting the pulp to high consistency (HC) refining and optionally low consistency (LC) refining to the extent that the sack paper obtains the Gurley porosity; c) adding cationic polymer, such as cationic starch, to the pulp in an amount of 1.5-5.0 kg/ton paper; and d) adding size to the pulp in an amount of 0.4-2.0 kg/ton paper; and e) forming the sack paper from the pulp, wherein less than 2 kg/ton paper of anionic starch is added to the pulp.

Production of sack paper

There is provided a multilayered paper material for use in a valve sack for a hydraulic binder, comprising a paper layer, such as a Kraft paper layer, provided on at least one side with a pre-coating layer and a moisture barrier coating layer, wherein the pre-coating layer comprises inorganic filler and binder in a dry weight ratio of between 4:1 and 20:1.

Coated sack paper

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Solna, Sweden

Jonas Almkvist