METHOD OF MAGNETIC LIQUID PREPARATION Russian patent published in 2008 - IPC H01F1/44 

FIELD: instrument making.

SUBSTANCE: invention is related to preparation of magnetic liquids and may find application in division of non-magnetic materials according to density, and also in instrument making and those industries, where magnetic fluid seals are used. Method includes deposition of magnetite particles with alkali from solution, which contains ions of bi- and trivalent iron, determination of magnetite curing completion stage immediately after deposition of its particles. On completion of magnetite curing particles are stabilized and peptised in disperse medium, at that stabiliser is supplied in the form of its solution in organic liquid, which is easily dissolved in water, at that ratio of stabiliser quantity to organic liquid amounts to 1:1 ÷ 1:5. As organic liquid acetone is used, as well as alcohols C₁-C₃, tret-butyl alcohol.

EFFECT: method provides preparation of magnetic liquid stable in uneven magnetic field, reduction of power inputs and quantity of used reagents related to the II class of hazardous substances.

7 cl, 2 tbl, 3 ex