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US 7,828,934 B2Granted
Reactive cationic resins for use as dry and wet strength agents in sulfite ion-containing papermaking systems
AssigneeHercules Incorporated
InventorsShane Cyr, Henk Bakker, Willem Marinus Stevels, Ronald Richard Staib
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Abstract
This invention relates to resins useful for imparting strength to paper, the process of incorporating these resins into paper and the paper produced containing the resins. In particular the invention relates to resins useful for imparting dry-strength and wet-strength to paper under conditions of high sulfite ion concentrations.
Claims7
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.
3 more elements
Dependencies are inferred from the claim text.