Process for the production of paper
AssigneeEka Nobel AB
InventorHans E. Johansson
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Abstract
A process for the production of paper by forming and dewatering a suspension of cellulose containing fibres, and optional fillers, on a wire. The forming and dewatering is carried out in the presence of a combination of an aluminum compound, a cationic retention agent and a polymeric silicic acid having a high specific surface area. The combination of substances improves dewatering and retention of fines and fillers.
Claims25
A process for the production of paper comprising forming and dewatering a suspension of cellulose containing fibers on a wire, wherein the forming and dewatering takes place in the presence of three components comprising an aluminum compound, a cationic polymeric retention agent and a polymeric silicic acid having a specific surface area of at least 1050 m.sup.2 /g, said components being separately added to the stock prior to the forming and dewatering and wherein said aluminum compound is selected from the group consisting of alum, aluminates, aluminum chloride, aluminum nitrate, polyaluminum chlorides, polyaluminum sulfates, polyaluminum chlorides containing sulfate, and mixtures thereof, and further wherein said aluminum compound, calculated as Al.sub.2 O.sub.3, being added in a weight ratio to polymeric silicic acid of at least 0.01:1.
Dependencies are inferred from the claim text.