Patent · US Expired

Magnetic recording medium

US5792570A · kind A · utility

21Cited by
2References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 5, 1996
Grant dateAug 11, 1998
Priority date
Expiry dateNov 5, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/25
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A magnetic recording medium comprising a substrate and a magnetic layer provided thereon, the magnetic layer containing: PA1 a binder, PA2 (a) an acicular ferromagnetic metal powder having an average major axis length of 0.05 to 0.14 .mu.m and a coercive force of 1700 to 2300 Oe or (c) a tabular hexagonal ferrite powder having a tabular diameter of 0.01 to 0.07 .mu.m and a coercive force of 1400 to 2200 Oe, and PA2 (b) a spherical or amorphous spinel ferrite powder having an average particle size of 0.005 to 0.09 .mu.m and a coercive force of more than 0 and less than 150 Oe, wherein the mixing ratio of the spinel ferrite powder (b) to the ferromagnetic metal powder (a) or the hexagonal ferrite powder (c), i.e., (b)/(a) or (b)/(c), is 0.03 to 0.3 by weight.

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