Patent · US Expired

Magnetic recording medium

US5795642A · kind A · utility

12Cited by
3References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 1, 1996
Grant dateAug 18, 1998
Priority date
Expiry dateNov 1, 2016

Classification

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

Abstract

Magnetic recording media comprising a nonmagnetic substrate, a surface layer and a back layer, the surface layer having an intermediate layer provided on the surface side of the nonmagnetic substrate and a magnetic layer as a top layer, the back layer having a backcoating layer provided on the back side of the nonmagnetic substrate, the magnetic layer containing a ferromagnetic metal powder and a binder, wherein the surface layer has a residual solvent content of 5 to 1000 ppm, the ferromagnetic metal powder is a ferromagnetic metal powder mainly comprising iron and containing 0.8 to 20 parts by weight of at least one element selected from Group IIIa elements, inclusive of lanthanides, of the Periodic Table per 100 parts by weight of Fe atoms, the magnetic layer has a thickness of 0.05 to 0.6 .mu.m, the magnetic layer has a center-line surface roughness Ra of 1 to 5 nm, the back layer has a residual solvent content of 5 to 800 ppm, and the backcoating layer has a center-line surface roughness Ra of 2 to 8 nm, exhibit excellent electromagnetic characteristics and storage stability.

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