Cationic pigments
US5336311A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 7, 1992 |
| Grant date | Aug 9, 1994 |
| Priority date | — |
| Expiry date | Jul 7, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2004/61
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
This invention relates to structural aggregate pigment products that are cationic, and have improved wet-end retention. A method for converting anionic pigments to cationic pigments is also provided. More particularly, a structural aggregate pigment comprising a clay and/or titanium dioxide or other particulate components, and a functional microgel made from silicon and aluminum or zinc gel formers and a gelling agent such as calcium chloride, can be cationized by adding an effective amount of modified or unmodified epichlorhydrin dimethylamine condensate to a slurry of the structured pigment. The resulting cationic pigments have superior papermaking characteristics and a much improved retention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.