A method for the preparation of finely divided magnetic hexa ferrites by spray drying of barium salts with iron oxides as well as the use of the resultant hexa ferrites

摘要

the present invention relates to a process for the production feinteiliger magnetic hexaferrite the general composition of $a m (i) 1 - xm and ym (ii) (iii) zfe12 - (y + z) o19, with $o x = 0.5, 0 = (y + z) = 3, o = and = 1.5, o = z = 1.5 and (x + y + z) = 1.0 $a m (i) = ba, sr, ca, pb or a combination of re and the singlet cation group li, na, rb, cs, ag, tl and re = la, y, sc,bi or other rare earth elements, and $a m (ii) = fe (ii), mn, co, ni, zn, cu, cd, mg, sn (ii) and (iii) $a m = ti, zr, hf, ga, sn (iv), ge, in, sc, nb, ta, v, as, sb, bi, al, cr (iii), mo, w $a mean and the use of these hexaferritpigmente in magnetic aufzeichnungsmedien, sicherheitsmarkier activity, markers of banknotes, transferbu00e4ndern and tickets.