Patent ID: 7828934
Filing Date: 2010-11-09
Classification: C08F,D21H

Abstract:
1. A process for making paper with improved strength comprising the steps of: a. forming an aqueous suspension of cellulosic fibers wherein the aqueous suspension contains a sulfite level in excess of 20 ppm, b. adding an effective amount of a cationic resin to the aqueous suspension of cellulosic fibers, c. forming the cellulosic fibers into a sheet, and d. drying the sheet to produce a paper, wherein the improvement to strength is provided by the cationic resin of step b) and wherein the cationic resin of step b) comprises a single component copolymer produced from acrylamide, diallyldimethylammonium chloride, and glyoxal wherein the diallyldimethylammonium chloride comprises greater than 25 mole % of the copolymer before reaction with dialdehyde.