Patent · US Expired

Perpendicular magnetic recording medium and manufacturing method thereof

US4731300A · kind A · utility

18Cited by
1References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 26, 1986
Grant dateMar 15, 1988
Priority date
Expiry dateFeb 26, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/12931
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A perpendicular magnetic recording medium comprises a recording medium base, a low coercivity layer formed on the recording medium base and having a low coercivity in an in-plane direction thereof, and a high coercivity layer formed on the low coercivity layer and having a high coercivity in a direction perpendicular to a surface of the low coercivity layer. The low coercivity layer and the high coercivity layer are formed from the same magnetic material and constitute a magnetic layer. A method of manufacturing this perpendicular magnetic recording medium comprises a single magnetic layer forming process of successively and continuously forming the low coercivity layer and the high coercivity layer on the recording medium base by using the same magnetic material as a depositing material.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.