Manufacture of acicular cobalt-modified magnetic iron oxide

Details Manufacture of acicular cobalt-modified magnetic iron oxide Manufacture of acicular cobalt-modified magnetic iron oxide

1978-01-25

1980-02-12

Cooper, Jack

Compositions

Magnetic

Iron-oxygen compound containing

427127, 427215, C01G 4906

Patent

active

041883020

ABSTRACT:
A process for the manufacture of an acicular magnetic iron oxide containing from 0.5 to 10 percent by weight of cobalt and up to 24 percent by weight of divalent iron, each based on the amount of iron(III) oxide, wherein an aqueous suspension of gamma-iron(III) oxide, containing cobalt(II) and iron(II) ions, the suspension having a hydroxyl ion concentration of more than 3.6.times.10.sup.-6 moles/liter, is heated at from 50.degree. to 100.degree. C. for at least 15 minutes, and the resulting precipitate is filtered off, washed until neutral, dried at below 100.degree. C. and thereafter heated at from 100.degree. to 200.degree. C.
The products thus obtained give, even when their cobalt content is low, a very high coercive force, while the effect of temperature on the coercive force and residual induction is very slight.

REFERENCES:
patent: 4015030 (1977-03-01), Sasazawa et al.
patent: 4066564 (1978-01-01), Sasazawa et al.

Affiliated with

Also associated with

Rating

Manufacture of acicular cobalt-modified magnetic iron oxide does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Manufacture of acicular cobalt-modified magnetic iron oxide, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Manufacture of acicular cobalt-modified magnetic iron oxide will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1854357