摘要 |
The present invention relates to a method of producing magnetite particles useful for the production of toners by(a) placing an alkaline component in the form of an aqueous solution in a vessel under a protective gas,(b) adding 1.0 to 3.0 mol %, relative to Fe of the magnetite, of a silicate component to form a reaction mixture,(c) heating the reaction mixture to a precipitation temperature of 60 to 80° C.,(d) adding an iron(II) component at a rate of 0.5 to 1.5 mol of Fe/hour per mol of the alkaline component until the pH of the suspension is 7.0 to 8.5, and(e) oxidizing the suspension with an oxidizing agent at a rate of 20 to 5 mol % of Fe(II)/hour to an Fe(III) content of 65 to 75 mol % of Fe(III).
|