US4425250A
Expired / Lapsed
US
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Preparation of finely divided ferrite powders
Assignee: BASF SE
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Filing: 1982-08-16
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Granted: 1984-01-10
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Expires: 2002-08-16
Abstract
Abstract A process for the preparation of finely divided ferrites of the general formula MeFe.sub.2 O.sub.4 (I) where Me=aMn+bNi+cZn+dCo+eFe(II), and the atomic weight ratios a, b, c, d and e are each from 0 to 1 and their sum is 1, or M.sup.1.sub.2 Me.sup.1.sub.2 Fe.sub.12 O.sub.22 (II) where M 1 is barium, strontium, calcium and/or lead, and Me 1 is divalent manganese, copper, iron, cobalt, nickel, zinc, magnesium and/or equimolar amounts of lithium and trivalent iron, or M.sup.2 (Me.sup.2 Ti).sub.x Fe.sub.12-2x O.sub.19 (III) where M 2 is barium or strontium, Me 2 is zinc, nickel and/or cobalt and x is from 0 to 2.0, wherein the salts required for the particular composition are mixed with sodium carbonate and/or potassium carbonate, the mixture obtained is heated at 700° to 1200° C., and the resulting ferrite is then isolated by leaching with water.
Inventors
- 👤 Hartmut Hibst
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:12
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/34; H01F1/36; C; C01; C01G; C01G49/00; C01G49/0018; C01G49/0036; C01G49/0054; C01G49/0072; C01G49/009; G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/706; G11B5/70626; G11B5/70642; G11B5/70678; C01P; C01P2002/00; C01P2002/30; C01P2002/32; C01P2002/50; C01P2002/52; C01P2002/54; C01P2004/00; C01P2004/20; C01P2004/22; C01P2004/50; C01P2004/60; C01P2004/61; C01P2004/62; C01P2006/00; C01P2006/12; C01P2006/42
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
187 words
A process for the preparation of a finely divided ferrite of the formula MeFe.sub.2 O.sub.4 (I) where Me=aMn+bNi+cZn+dCo+eFe(II), and the atomic weight ratios a, b, c, d and e are each from 0 to 1 and their sum is 1, or M.sub.2.sup.1 Me.sub.2.sup.1 Fe.sub.12 O.sub.22 (II) where M 1 is barium, strontium, calcium and/or lead, and Me 1 is divalent manganese, copper, iron, cobalt, nickel, zinc, magnesium and/or equimolar amounts of lithium and trivalent iron, or M.sup.2 (Me.sup.2 Ti).sub.x Fe.sub.12-2x O.sub.19 (III) where M 2 is barium or strontium, Me 2 is zinc, nickel and/or cobalt and x is from 0 to 2.0, wherein the Me, Me 1 , Me 2 , M 1 and/or M 2 salts required for the particular composition corresponding to the formula (I), (II) or (III), iron(III) chloride and sodium carbonate and/or potassium carbonate aare mixed as powders, with or without a powdered titanium compound to form a mixture of powders, the mixture obtained is heated at from 700° to 1200° C. and the resulting finely divided ferrite of the predetermined composition is isolated from the heated mixture by leaching with water.
Claim 2
Dependent Claim
187 words
A process for the preparation of a finely divided ferrite of the formula MeFe.sub.2 O.sub.4 (I) where Me=aMn+bNi+cZn+dCo+eFe(II), and the atomic weight ratios a, b, c, d and e are each from 0 to 1 and their sum is 1, or M.sub.2.sup.1 Me.sub.2.sup.1 Fe.sub.12 O.sub.22 (II) where M 1 is barium, strontium, calcium and/or lead, and Me 1 is divalent manganese, copper, iron, cobalt, nickel, zinc, magnesium and/or equimolar amounts of lithium and trivalent iron, or M.sup.2 (Me.sup.2 Ti).sub.x Fe.sub.12-2x O.sub.19 (III) where M 2 is barium or strontium, Me 2 is zinc, nickel and/or cobalt and x is from 0 to 2.0, wherein the Me, Me 1 , Me 2 , M 1 and/or M 2 salts required for the particular composition corresponding to the formula (I), (II) or (III), iron(III) chloride and sodium carbonate and/or potassium carbonate aare mixed as powders, with or without a powdered titanium compound to form a mixture of powders, the mixture obtained is heated at from 700° to 1200° C. and the resulting finely divided ferrite of the predetermined composition is isolated from the heated mixture by leaching with water.
Claim 3
Dependent Claim
99 words
A process for the preparation of an isotropic ferrite powder having a spinel structure, of the formula MeFe 2 O 4 (I), where Me=a Mn+b Ni+c Zn+d Co+e Fe(II), and the atomic weight ratios a, b, c, d and e are each from 0 to 1 and their sum is 1, wherein one or more Me salts, iron(III) chloride and sodium carbonate and/or potassium carbonate are mixed as powders to form a mixture of powders, the mixture obtained is heated at from 800°-1200° C. and the resulting isotropic ferrite is isolated from the heated mixture by leaching with water.
Claim 4
Dependent Claim
99 words
A process for the preparation of an isotropic ferrite powder having a spinel structure, of the formula MeFe 2 O 4 (I), where Me=a Mn+b Ni+c Zn+d Co+e Fe(II), and the atomic weight ratios a, b, c, d and e are each from 0 to 1 and their sum is 1, wherein one or more Me salts, iron(III) chloride and sodium carbonate and/or potassium carbonate are mixed as powders to form a mixture of powders, the mixture obtained is heated at from 800°-1200° C. and the resulting isotropic ferrite is isolated from the heated mixture by leaching with water.
Claim 5
Dependent Claim
125 words
A process for the preparation of a hexagonal Me 2 1 Y ferrite of the formula M 2 1 Me 2 1 Fe 12 O 22 (II), where M 1 is barium, strontium, calcium and/or lead and Me 1 is divalent manganese, copper, iron, cobalt, nickel, zinc, magnesium and/or equimolar amounts of lithium and trivalent iron, wherein an M 1 chloride or carbonate, an Me 1 chloride or carbonate, iron(III) chloride and sodium carbonate and/or potassium carbonate are mixed as powders to form a mixture of powders, the mixture obtained is heated at from 800° to 1050° C. and the flaky hexagonal Me 2 1 Y ferrite formed is then isolated from the resulting melt of sodium chloride and/or potassium chloride by leaching with water.
Claim 6
Dependent Claim
125 words
A process for the preparation of a hexagonal Me 2 1 Y ferrite of the formula M 2 1 Me 2 1 Fe 12 O 22 (II), where M 1 is barium, strontium, calcium and/or lead and Me 1 is divalent manganese, copper, iron, cobalt, nickel, zinc, magnesium and/or equimolar amounts of lithium and trivalent iron, wherein an M 1 chloride or carbonate, an Me 1 chloride or carbonate, iron(III) chloride and sodium carbonate and/or potassium carbonate are mixed as powders to form a mixture of powders, the mixture obtained is heated at from 800° to 1050° C. and the flaky hexagonal Me 2 1 Y ferrite formed is then isolated from the resulting melt of sodium chloride and/or potassium chloride by leaching with water.
Claim 7
Dependent Claim
121 words
A process for the preparation of a finely divided hexagonal ferrite of the formula M 2 (Me 2 Ti) x Fe 12-2x O 19 (III), where M 2 is barium or strontium, Me 2 is zinc, nickel and/or cobalt and x is from 0 to 2.0, wherein a barium or strontium salt, iron(III) chloride and sodium carbonate and/or potassium carbonate are mixed as powders, with or without a salt of zinc, nickel and/or cobalt as powders and a powdered titanium compound to form a mixture of powders, the mixture obtained is heated at from 700° to 1100° C. and the resulting finely divided flaky hexagonal ferrite of the above composition is then isolated from the heated mixture by leaching with water.
Claim 8
Dependent Claim
121 words
A process for the preparation of a finely divided hexagonal ferrite of the formula M 2 (Me 2 Ti) x Fe 12-2x O 19 (III), where M 2 is barium or strontium, Me 2 is zinc, nickel and/or cobalt and x is from 0 to 2.0, wherein a barium or strontium salt, iron(III) chloride and sodium carbonate and/or potassium carbonate are mixed as powders, with or without a salt of zinc, nickel and/or cobalt as powders and a powdered titanium compound to form a mixture of powders, the mixture obtained is heated at from 700° to 1100° C. and the resulting finely divided flaky hexagonal ferrite of the above composition is then isolated from the heated mixture by leaching with water.
References Cited (Backward Citations)
US3102099A
Cited
US3150925A
Cited
US3509057A
Cited
US3582266A
Cited
GB1254390A
Cited
US3634254A
Cited
GB1318889A
Cited
GB1317088A
Cited
US3793443A
Cited
US3810973A
Cited
US4120807A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-09 | 1987-07-11 | 1988-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-09 | 1991-07-11 | 1992-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-09 | 1995-07-11 | 1996-01-10 | $7700.00 | Window Closed / Lapsed |