Patent ID: 8758562
Filing Date: 2014-06-24
Classification: D21H

Abstract:
1. A method for manufacturing paper, paperboard or cardboard comprising the steps of (a) pulping a cellulosic material containing a starch; (b) treating the cellulosic material containing the starch with one or more biocides in an amount sufficient to prevent microbiological degradation of at least a portion of the starch; and (c) adding an ionic polymer and an auxiliary ionic polymer to the cellulosic material; wherein the ionic polymer and the auxiliary ionic polymer are cationic; wherein the relative difference between the ionicity of the auxiliary ionic polymer and the ionicity of the ionic polymer is at least 5 mole.-%, wherein the ionicity is the molar content of ionic monomer units relative to the total amount of monomer units; and wherein the ionic polymer has a higher average molecular weight than the auxiliary ionic polymer.