Magnetic recording medium
US5510177A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1992 |
| Grant date | Apr 23, 1996 |
| Priority date | — |
| Expiry date | Dec 21, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31971
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording medium having two or more magnetic layers is disclosed, comprising a first magnetic layer and a second magnetic layer which-have been provided in this order on a surface of a nonmagnetic support, and which contain ferromagnetic particles and a binder, wherein said second magnetic layer (outermost layer) contains nonmagnetic particles having a pH of less than 7, and a Mohs' hardness of 6 or more, in an amount of from 1 to 20 parts by weight, per 100 parts by weight of the ferromagnetic particles in the second magnetic layer, and said first magnetic layer contains nonmagnetic particles having a pH of 7 or more, and a Mohs' hardness of 6 or more, in an amount of from 5 to 50 parts by weight, per 100 parts by weight of the ferromagnetic particles in the first magnetic layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.