Method of making paper containing cationic starch and an anionic retention aid
AssigneeAnheuser-Busch, Incorporated
InventorsJohn E. Voigt, Herbert Pender, Jr.
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Abstract
This application covers the use of a cationic starch and a polyacrylamide polymer as a retention aid in the manufacture of paper. The resulting paper containing the additives is characterized by improved retention of pigments.
Claims2
A method of papermaking comprising the steps of adding from about 0.015% to about 4% by weight based on the weight of dry pulp of a cationic starch having a degree of substitution of about 0.0034 to about 0.07 and consisting essentially of the reaction product of starch and an amine alkene halide salt and from about 5 ppm to about 250 ppm based on dry pulp of an anionic polyacrylamide polymer to the pulp in a papermaking process prior to depositing the pulp on a screen, said polymer having an average molecular weight of about 4 .times. 10.sup.6 to about 6 .times. l0.sup.6.
Dependencies are inferred from the claim text.