| 摘要 |
The present invention relates to a process of making paper or paperboard, the process including introducing a dual retention system into a cellulosic thin stock, subjecting the cellulosic thin stock to one or more shear stages, and then draining the cellulosic thin stock on a moving screen to form a dried sheet, wherein the dual retention system consists of a first polymeric retention aid and a second polymeric retention aid, the first polymeric retention aid is a water-soluble cationic polymer exhibiting an intrinsic viscosity of at least 6 dl/g, the second polymeric retention aid is a water-soluble cationic polymer exhibiting an intrinsic viscosity of from 4 to 9 dl/g, and the second polymeric retention aid has a greater cationic charge density than the first polymeric retention aid. |
