TiO.sub.2 Pigment coated with dense silica and porous alumina/silica
US4075031A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 30, 1976 |
| Grant date | Feb 21, 1978 |
| Priority date | — |
| Expiry date | Sep 30, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/60
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A coated titanium dioxide pigment and the process for its preparation consisting essentially of a core of pigmentary titanium dioxide (TiO.sub.2), a dense inner coating of dense amorphous silica (SiO.sub.2) in an amount from 1 to 10% by weight, based on the uncoated pigment, and, optionally, up to 15% of alumina (Al.sub.2 O.sub.3) and a porous outer coating of porous silica (SiO.sub.2) and alumina (Al.sub.2 O.sub.3), said porous silica being present in an amount from 0.5 to 15% by weight and said alumina being present in an amount from 0 to 15% by weight, based on the uncoated pigment. As a component of coating compositions, this pigment providesa high degree of hiding power and durability for indoor and outdoor applications.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.