Sizing composition, its use and a method for producing paper, board or the like
US10407831B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 2015 |
| Grant date | Sep 10, 2019 |
| Priority date | — |
| Expiry date | Sep 4, 2035 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21H23/22
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The invention relates to a composition for sizing of a surface of paper, board or the like and its use for increasing strength properties of paper, board or the like. The composition has a solids content of 3-30%, and it comprises degraded non-ionic starch, and at least 0.5 weight-% of anionic polyacrylamide, which has a molecular weight, MW, >500 000 g/mol and <2 500 000 g/mol and an anionicity in the range of 4-35 mol-%. The invention further relates also to a method for producing paper, board or the like, which comprises addition of a first strength composition, which comprises a cationic agent, to a fiber stock, formation of a fibrous web from the fiber stock, drying of the fibrous web to dryness of at least 60%, and application of a second strength composition, which comprises an anionic hydrophilic polymer and a starch component, on the surface of the fibrous web.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.