Process for manufacture of paper
AssigneeNational Starch and Chemical Investment Holding Corporation
InventorsVelayudhan N. G. Kumar, Patrick G. Jobe
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Abstract
A process for the manufacture of paper from pulp employs at least one graft copolymer of starch selected from the group consisting of starch graft-polymethacrylic acid, starch graft-polyacrylic acid, cationic starch graft-polymethacrylic acid and cationic starch graft-polyacrylic acid as a wet-end additive. The graft copolymer preferably has an add on amount of acid of from about 0.1 to about 50% based on the weight of the starch, and is typically added to cellulosic pulp in an amount of from about 0.1 to about 10% based on the weight of the pulp. Such wet-end additives are also useful in processes involving relatively high alum levels of up to about 15 or 25%, based on the weight of the pulp.
Claims9
In a process for the manufacture of paper from an aqueous pulp furnish, the improvement comprising adding to the aqueous pulp furnish at least about 0.1% based on the weight of the pulp, of at least one graft copolymer of starch selected from the group consisting of starch graft-polymethacrylic acid, starch graft-polyacrylic acid, cationic starch graft-polymethacrylic acid and cationic starch graft-polyacrylic acid, wherein said graft copolymer has an add-on amount of polymethacrylic or polyacrylic acid of from 0.1 to 5% by weight of starch.
Dependencies are inferred from the claim text.