Patent · US Expired

Transparent magnetic recording layers and photographic elements containing the same

US5252441A · kind A · utility

19Cited by
9References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 6, 1990
Grant dateOct 12, 1993
Priority date
Expiry dateNov 6, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B5/633
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A photographic element including a light-sensitive layer and a transparent magnetic layer wherein the magnetic particles in the transparent binder are cobalt surface treated gamma iron oxide (Fe.sub.2 O.sub.3) having a specific area of at least 30 m.sup.2 /g, the particles being coated with from about 10 to about 50% by weight of a material having a refractive index less than that of the binder, the particles having a powder coercivity greater than about 450 Oe.

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