Global Patent Index - EP 0043921 B1

EP 0043921 B1 19840516 - FERROMAGNETIC METAL PARTICLES ESSENTIALLY CONSISTING OF IRON WITH SURFACE COATING, PROCESS FOR THEIR MANUFACTURE AS WELL AS THEIR USE IN MAKING MAGNETIC-RECORDING MEDIA

Title (en)

FERROMAGNETIC METAL PARTICLES ESSENTIALLY CONSISTING OF IRON WITH SURFACE COATING, PROCESS FOR THEIR MANUFACTURE AS WELL AS THEIR USE IN MAKING MAGNETIC-RECORDING MEDIA

Publication

EP 0043921 B1 19840516 (DE)

Application

EP 81104590 A 19810615

Priority

DE 3026696 A 19800715

Abstract (en)

[origin: US4360377A] Ferromagnetic metal particles, consisting essentially of iron and comprising a core, containing not less than 85% by weight of metallic iron, and an iron oxide plus chromium oxide surface layer surrounding this core, which layer additionally contains one or more elements selected from the group comprising zinc, phosphorus in the form of phosphate, aluminum, calcium, strontium, barium, cadmium, lead, cobalt and nickel in a total amount of not more than 9.5% by weight, based on the total amount of the metal particles, and a process for the production of such particles.

IPC 1-7

G11B 5/70; H01F 1/06; B22F 1/02; B22F 9/24

IPC 8 full level

B22F 1/02 (2006.01); B22F 1/16 (2022.01); B22F 9/24 (2006.01); G11B 5/70 (2006.01); H01F 1/06 (2006.01); H01F 1/09 (2006.01)

CPC (source: EP US)

B22F 1/16 (2022.01 - EP US); B22F 9/24 (2013.01 - EP US); H01F 1/061 (2013.01 - EP US); H01F 1/09 (2013.01 - EP US); Y10T 428/12181 (2015.01 - EP US)

Designated contracting state (EPC)

DE FR GB NL

DOCDB simple family (publication)

EP 0043921 A1 19820120; EP 0043921 B1 19840516; DE 3026696 A1 19820218; DE 3163612 D1 19840620; US 4360377 A 19821123

DOCDB simple family (application)

EP 81104590 A 19810615; DE 3026696 A 19800715; DE 3163612 T 19810615; US 27866381 A 19810629