Method for making paper and cardboard with high dry strength and resulting papers and cardboards
US7883603B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 2006 |
| Grant date | Feb 8, 2011 |
| Priority date | — |
| Expiry date | Jan 26, 2028 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21H17/45
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A method for making a sheet of paper and/or cardboard and the like, comprises, prior to forming said sheet, adding to the fibrous suspension, separately or mixed, in any sequence of introduction, into one or more injection points, at least three dry strength agents respectively: first agent corresponding to a (co)polymer having a cationic filler density higher than 1 meq/g and exhibiting primary amine functions; a second agent corresponding to a synthetic organic (co)polymer having cationic filler density higher than 0.1 meq/g; and a third agent corresponding to a (co)polymer having an anionic filler density higher than 0.1 meq/g.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.