PAPPERSTILLVERKNINGSFORFARANDE

摘要

In a process for making paper from an aqueous paper pulp, especially a pulp containing bleached/unbleached mechanical pulps or unbleached chemical pulps, a combination of chemicals is added for improving drainage and retention. As drainage-and retention-improving aids are added a cationic polyacrylamide and a sol of colloidal inorganic particles having at least one surface layer of aluminium silicate or aluminum-modified silicic acid.