| 摘要 |
A process for making paper which has a high dry strength by adding a cationic polymer to the paper stock and draining the latter with sheet formation, or by applying a cationic polymer onto the surface of paper, the said polymer being used in each case in an amount of from 0.05 to 3.0% by weight, based on dry fiber or dry paper. There is used as the cationic polymer a water-soluble copolymer of a compound of the formula wherein X is an acid radical, containing as copolymerized units, from 1 to 30% by weight of said compound and from 99 to 70% by weight of acrylamide and/or methacrylamide, the K value of said copolymer being from 50 to 250. Apart from its high dry strength, the polymer shares virtually no tendency to foam under processing conditions and, when added to the paper stock, exhibits only slight sensitivity to interfering substances. |
