Pigments
US5114486A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 1991 |
| Grant date | May 19, 1992 |
| Priority date | — |
| Expiry date | Mar 26, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2004/84
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A new process for the production of pigments suitable for use in paper laminates has been developed in which a metal oxide is treated with a water-soluble salt of zinc and a phosphate or phosphoric acid and subsequently with an alkali metal aluminate in such a manner that there is deposited on the metal oxide a coating containing zinc and phosphate ions together with aluminium ions. The pH of the dispersion following the metal oxide is maintained at a value not exceeding 8.0 during precipitation. A particularly useful pigment is produced which has a coating containing zinc ions in an amount of 0.5 to 5% by weight as ZnO, phosphate ions in an amount of 0.2 to 3% as P.sub.2 O.sub.5 and aluminium ions in an amount of 0.5 to 5% expressed as Al.sub.2 O.sub.3 on the weight of TiO.sub.2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.