Patent · US Expired

Magnetic recording medium comprising a mixed magnetic region having a thickness relative to the total thickness of magnetic layers

US6063489A · kind A · utility

21Cited by
5References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 6, 1998
Grant dateMay 16, 2000
Priority date
Expiry dateAug 6, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/265
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A magnetic recording medium having a lower magnetic layer 3 and an upper magnetic layer 4 is disclosed, wherein the lower magnetic layer 3 contains tabular magnetic particles and acicular nonmagnetic inorganic particles and has a thickness of 0.5 to 2.5 .mu.m, the tabular magnetic particles being oriented with their plane having the longest diameter tilted at an angle of 70 to 90.degree. in average with the plane of the magnetic recording medium, the upper magnetic layer 4 contains acicular magnetic particles and has a thickness of not greater than 0.3 .mu.m, and a mixed magnetic region 6 which comprises tabular magnetic particles and acicular magnetic particles, mixed together, and formed between the upper and lower magnetic layers, a thickness m of the mixed magnetic region 6 being 1 to 20% of the total thickness T of all the magnetic layers.

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