Process for the production of paper
US6918995B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 6, 2001 |
| Grant date | Jul 19, 2005 |
| Priority date | — |
| Expiry date | Aug 31, 2021 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21H21/16
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The invention relates to a process for the production of paper from an aqueous suspension containing cellulosic fibers, and optional fillers, which comprises separately adding to the suspension a cationic organic polymer having one or more aromatic groups and an anionic polymer having one or more aromatic groups, the anionic polymer being selected from step-growth polymers, polysaccharides and naturally occurring aromatic polymers and modifications thereof, forming and draining the suspension on a wire, with the proviso that if the anionic polymer is a step-growth polymer it is not an anionic melamine-sulphonic acid condensation polymer. The invention further relates to a process for the production of paper from an aqueous suspension containing cellulosic fibers, and optional fillers, which comprises separately adding to the suspension a cationic organic polymer having one or more aromatic groups and an anionic polymer having one or more aromatic groups, forming and draining the suspension on a wire, with the proviso that the anionic polymer is not an anionic polystyrene sulphonate or anionic melamine-sulphonic acid condensation polymer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.