Granted Patent B2

US 9,206,551 · App. 14/105,259 · Granted Dec 8, 2015

Abstract

Claims (13)

1. A process for the production of paper, board and cardboard having high dry strength,

the process comprising:

metering into a paper stock an aqueous composition comprising a nanocellulose comprising cellulose fibers and a water-soluble cationic polymer comprising a polymer comprising a vinylamine unit;

draining the paper stock to obtain paper product; and

drying the paper product.

2. The process according to claim 1 , wherein the nanocellulose has a length dimension below 1000 μm and a fiber thickness is in a range from 50 μm to 3 nm.

3. The process according to claim 2 , wherein at least 80% of the cellulose fibers of the nanocellulose have a fiber thickness in a range from 50 μm to 3 nm.

4. The process according to claim 3 , wherein at least 80% of the cellulose fibers of the nanocellulose have a fiber thickness in a range from 1 μm to 5 nm.

5. The process according to claim 1 , wherein the nanocellulose has a length dimension below 1000 μm, a fiber thickness in a range from 50 μm to 3 nm, and

wherein the nanocellulose comprises from 5 ppm to 2% by weight of an ionic fluid, based on a total mass of the nanocellulose.

6. The process according to claim 5 , wherein at least 80% of the cellulose fibers of the nanocellulose have a fiber thickness of from 50 μm to 3 nm and comprise from 5 ppm to 2% by weight of an ionic liquid, based on a total mass of the nanocellulose.

7. The process according to claim 1 , wherein a molar mass M w of the cationic polymer is in a range from 5000 to 5 million g/mol.

8. The process according to claim 1 , wherein a charge density of the cationic polymer is in a range from 0.5 to 23 meq/g.

Assignments (11)