Metal additions to pigments of pseudobrookite-titanium dioxide structure
US4036662A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 1975 |
| Grant date | Jul 19, 1977 |
| Priority date | — |
| Expiry date | Oct 20, 1995 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2002/52
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
In the production of temperature-stable inorganic pigment of pseudobrookite-titanium dioxide structure having the composition Fe.sub.2 TiO.sub.5.sup.. x TiO.sub.2, wherein x is from 0 to about 15, by preparing a suspension of finely divided titanium dioxide or titanium dioxide hydrate and at least one of finely divided iron oxide, iron oxide hydroxide, iron hydroxide and iron carbonate, removing the aqueous phase of the suspension from a solid residue and calcining the residue at a temperature in the range of about 600.degree. to 1100.degree.C, the improvement which comprises including in the suspension or in the solid residue at least one compound of a metal selected from the group consisting of lithium, sodium, potassium, magnesium, zinc, calcium, aluminum, copper, vanadium, chromium, manganese, cobalt and nickel, the compound being present in a quantity to provide about 0.1 to 10 % by weight of metal based on the pigment. With the addition of compounds of lithium, sodium, potassium, magnesium, zinc, calcium or aluminum even in small amounts a much purer yellow color results.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.