Process for the production of paper
US5858174A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 8, 1996 |
| Grant date | Jan 12, 1999 |
| Priority date | — |
| Expiry date | Jul 8, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L2205/02
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The invention relates to a process for the production of paper from a suspension of cellulose containing fibers, and optional fillers, comprising adding to the suspension a low molecular weight cationic organic polymer, a high molecular weight cationic or amphoteric polymer and anionic inorganic particles, forming and draining the suspension on a wire, wherein the low molecular weight polymer has a molecular weight below 700,000 and the high molecular weight polymer has a molecular weight above 1,000,000, said polymers being simultaneously added to the suspension. The invention further relates to a polymer mixture in the form of an aqueous dispersion comprising at least one high molecular weight cationic or amphoteric acrylamide-based polymer having a molecular weight above 1,000,000, at least one low molecular weight cationic organic polymer having a molecular weight below 700,000 and at least one water-soluble inorganic salt, the weight ratio of said high molecular weight polymer to said low molecular weight polymer being within the range of from 9:1 to 1:2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.