SOL OF SILICIC ACID AND METHOD FOR MANUFACTURING PAPER Russian patent published in 1997 - IPC

FIELD: paper making. SUBSTANCE: invention relates to silicic acid sol and a method for manufacturing paper using this sol. Sol of invention has content of silica disperse phase corresponding to S-value in the range 15 to 40%, advantageously 15 to 35%, and contains silica particles modified and not modified with aluminium with specific surface area 300-700 sq.m/g, advantageously 400 to 650 sq.m/g. Method of manufacturing paper consists in adding to pulp fiber-containing cellulose, polymer, and anionic sol of silicic acid as described above followed by shaping and dehydrating the pulp on cloth. Polymer used is a cationic, e.g. acrylamide-based or amphoteric polymer. As polymer, cellulose pulp containing filler is used. EFFECT: essentially increased retention and dehydration effect. 9 cl, 2 tbl