Production of paper using slica-based-sols
US7670460B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2006 |
| Grant date | Mar 2, 2010 |
| Priority date | — |
| Expiry date | Dec 23, 2027 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B33/146
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for the production of paper which includes the steps of providing an aqueous suspension containing cellulosic fibers, and optional fillers; adding to the suspension: (a) at least one charged organic polymer; and (b) an aqueous sol containing silica-based particles; wherein the sol has: (i) an S-value within the range of from 10 to 45%; (ii) a viscosity within the range of from 5 to 40 cP; and (iii) a molar ratio of SiO2 to M2O, where M is alkali metal or ammonium, within the range of from 10:1 to 40:1; and (III) forming and draining the suspension on a wire. The invention is further directed to processes for making paper wherein the added sol has: (i) an S-value within the range of from 10 to 45%; (ii) a viscosity within the range of from 5 to 40 cP; and (iii) a silica content of at least 10% by weight, or wherein the added sol has: (i) an S-value within the range of from 10 to 45%; (ii) a viscosity within the range of from 7 to 25 cP; (iii) a silica content of at least 10% by weight; (iv) a molar ratio of SiO2 to M2O, where M is alkali metal or ammonium, within the range of from 10:1 to 40:1; and (v) a pH of at least 10.6. The invention is further directed to a process f…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.