Non-magnetic composite particles, process for producing the same and magnetic recording medium using the same
US6544647B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 2000 |
| Grant date | Apr 8, 2003 |
| Priority date | — |
| Expiry date | Jul 25, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2998
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Non-magnetic composite particles composed of non-magnetic core particles having an average particle size of 0.01 to 0.3 &mgr;m, and inorganic fine particles having an average particle size of 0.001 to 0.07 &mgr;m. The fine particles are present in an amount of 0.1 to 20% by weight based on the weight of the non-magnetic particles are on the surface of each non-magnetic particle, and are fixed or anchored on the surface of each non-magnetic particle through a silicon compound.The non-magnetic composite particles have a high polishing effect and a high dispersibility, and are useful as a non-magnetic undercoat layer for a magnetic recording medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.