Papermaking process with improved retention and drainage
US5098520A · kind A · utility
93Cited by
8References
19Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 25, 1991 |
| Grant date | Mar 24, 1992 |
| Priority date | — |
| Expiry date | Jan 25, 2011 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21H17/67
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A papermaking process includes the steps of adding to the papermaking celllulosic slurry first a high molecular weight cationic polymer and then a medium weight anionic polymer. The cationic polymer is added after the addition of filler, but before at least one of the shear stages to which the slurry is subjected prior to sheet formation and drainage. The anionic polymer is added after the shear stage which is subsequent to the addition of the cationic polymer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.