Patent · US Expired

Magnetic recording medium

US4239835A · kind A · utility

27Cited by
11References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 13, 1977
Grant dateDec 16, 1980
Priority date
Expiry dateJul 13, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31678
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A magnetic recording medium wherein a ferromagnetic substance consisting of Fe, Co, Ni or alloy thereof is vacuum evaporated and deposited on a substrate made of a plastic film or a sheet of non-magnetic metal. The thin ferromagnetic film has the columnar crystal structure, and the columnar crystals are coated with a layer of oxide of the ferromagnetic substance.

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