Tin-containing granular magnetic oxide particles and process for producing the same
US6596255B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | May 22, 2001 |
| Grant date | Jul 22, 2003 |
| Priority date | — |
| Expiry date | Jan 30, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2004/62
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Tin-containing granular magnetic oxide particles comprising spinel-type crystal represented by the formula:Fe3-xSnxO4wherein x is 0.14 to 0.48, andhaving a Fe2+ content of 17 to 22% by weight, a lattice constant of 8.41 to 8.49 å, a magnetization value of 20 to 50 Am2/kg when measured under an applied magnetic field of 79.6 kA/m, and a depth of a groove of not more than 40 &mgr;m at which three or more continuous lines each having a length of not less than 10 mm are developed in a pigment dispersion test using a grind-meter when measured by Hoover's muller method according to JIS K5101 (1991) 9.1. The tin-containing granular magnetic oxide particles of the present invention exhibit a sufficient blackness, a small magnetization value and an excellent dispersibility.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.