Global Patent Index - EP 0024692 A3

EP 0024692 A3 19810826 - PROCESS FOR PREPARING ACICULAR FERROMAGNETIC IRON PARTICLES, AND THEIR USE

Title (en)

PROCESS FOR PREPARING ACICULAR FERROMAGNETIC IRON PARTICLES, AND THEIR USE

Publication

EP 0024692 A3 19810826 (DE)

Application

EP 80104974 A 19800821

Priority

DE 2935357 A 19790901

Abstract (en)

[origin: US4295879A] A process for the manufacture of acicular ferromagnetic iron particles by reducing an iron(III) oxide which carries a shape-stabilizing surface coating and has been produced by heating acicular iron(III) oxide hydroxide at 250 DEG -390 DEG C. in an atmosphere containing water vapor at a partial pressure of not less than 30 mbar, with hydrogen at 275 DEG -425 DEG C.

IPC 1-7

H01F 1/06; B22F 9/22; G11B 5/70

IPC 8 full level

G11B 5/706 (2006.01); B22F 9/22 (2006.01); C01G 49/02 (2006.01); C09D 5/23 (2006.01); C09D 7/12 (2006.01); G11B 5/70 (2006.01); H01F 1/06 (2006.01)

CPC (source: EP US)

B22F 9/22 (2013.01 - EP US); H01F 1/061 (2013.01 - EP US); H01F 1/065 (2013.01 - EP US)

Citation (search report)

Designated contracting state (EPC)

DE FR GB NL

DOCDB simple family (publication)

EP 0024692 A2 19810311; EP 0024692 A3 19810826; EP 0024692 B1 19840328; DE 2935357 A1 19810910; DE 3067268 D1 19840503; JP S5641835 A 19810418; US 4295879 A 19811020

DOCDB simple family (application)

EP 80104974 A 19800821; DE 2935357 A 19790901; DE 3067268 T 19800821; JP 11854180 A 19800829; US 17424080 A 19800731