Magnetic recording medium possessing a magnetic layer having plural oxygen-containing regions
US6861126B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 6, 2003 |
| Grant date | Mar 1, 2005 |
| Priority date | — |
| Expiry date | Feb 6, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
On a polymeric substrate 1, there is formed with a single magnetic layer 2 containing a ferromagnetic metal and oxygen. The magnetic layer 2 is divided into three regions equally in the depth direction from the polymeric substrate 1 to the surface of the magnetic layer 2, wherein the three regions are defined as a first region 21, a second region 22 and a third region 23 respectively in accordance with a process of forming the magnetic layer 2. With defining that a maximum value of oxygen concentration in the first region 21 is “Max 1”, a minimum value of oxygen concentration in the second region 22 is “Min 2”, and a maximum value of oxygen concentration in the third region 23 is “Max 3” respectively, these values “Max 1”, “Min 2” and “Max 3” have relations of “Min 2”<“Max 1” and “Min 2”≦“Max 3”≦“Max 1”.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.