GB1432643A - Manufacture of cobalt-modified ypsilon-iron-iii-oxides - Google Patents
Manufacture of cobalt-modified ypsilon-iron-iii-oxidesInfo
- Publication number
- GB1432643A GB1432643A GB4107273A GB4107273A GB1432643A GB 1432643 A GB1432643 A GB 1432643A GB 4107273 A GB4107273 A GB 4107273A GB 4107273 A GB4107273 A GB 4107273A GB 1432643 A GB1432643 A GB 1432643A
- Authority
- GB
- United Kingdom
- Prior art keywords
- cobalt
- iron
- oxide
- iii
- magnetite
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/62—Record carriers characterised by the selection of the material
- G11B5/68—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
- G11B5/70—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer
- G11B5/706—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material
- G11B5/70626—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances
- G11B5/70642—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances iron oxides
- G11B5/70652—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances iron oxides gamma - Fe2 O3
- G11B5/70668—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances iron oxides gamma - Fe2 O3 containing a dopant
- G11B5/70673—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances iron oxides gamma - Fe2 O3 containing a dopant containing Co
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/62—Record carriers characterised by the selection of the material
- G11B5/68—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent
- G11B5/70—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer
- G11B5/706—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material
- G11B5/70626—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances
- G11B5/70642—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances iron oxides
- G11B5/70652—Record carriers characterised by the selection of the material comprising one or more layers of magnetisable material homogeneously mixed with a bonding agent on a base layer characterised by the composition of the magnetic material containing non-metallic substances iron oxides gamma - Fe2 O3
- G11B5/70663—Preparation processes specially adapted therefor, e.g. using stabilising agents
Landscapes
- Hard Magnetic Materials (AREA)
- Compounds Of Iron (AREA)
Abstract
1432643 Cobalt-modified iron (III) oxide BASF AG 31 Aug 1973 [1 Sept 1972] 41072/73 Heading C1A Cobalt-modified γ-iron (III) oxide is made by (1) providing acicular iron oxide (e.g. α-Fe 2 O 3 ) or oxide hydrate (e.g. α-FeOOH) with a sinterpreventing coating; (2) reducing the coated needles to magnetite (Fe 3 O 4 ) at 350-650‹ C.; and then either (a) oxidizing the magnetite to γ-Fe 2 O 3 , applying a cobalt compound thereto, and then heating the cobalt-treated γ-Fe 2 O 3 to 80-300‹ C., or (b) applying a cobalt compound to the magnetite, and then heating the cobalttreated magnetite to 80-300‹ C., with oxidation to γ-Fe 2 O 3 . The coating on the acicular starting material may be formed by treating, it with oxyacids of phosphorus and/or boron or their salts, or by depositing oxides or hydroxides of Al, Zr, Si, or Cr from salt solutions. The cobalt content of the product may be 0À25-15 wt. per cent based on wt. of iron oxide. The cobalt content may be derived by impregnating the iron oxide with cobalt sulphate. Examples describe the preparation of γ-iron (III) containing 15 wt. per cent cobalt, and its magnetic properties. A magnetic recording tape incorporating the oxide is also described.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE19722243231 DE2243231C2 (en) | 1972-09-01 | 1972-09-01 | Process for the preparation of cobalt-doped γ-iron (III) oxide |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1432643A true GB1432643A (en) | 1976-04-22 |
Family
ID=5855337
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB4107273A Expired GB1432643A (en) | 1972-09-01 | 1973-08-31 | Manufacture of cobalt-modified ypsilon-iron-iii-oxides |
Country Status (4)
Country | Link |
---|---|
JP (1) | JPS5737532B2 (en) |
DE (1) | DE2243231C2 (en) |
FR (1) | FR2197818B3 (en) |
GB (1) | GB1432643A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4287233A (en) | 1979-02-13 | 1981-09-01 | Basf Aktiengesellschaft | Manufacture of acicular cobalt-containing magnetic iron oxide |
US4296149A (en) | 1979-02-13 | 1981-10-20 | Basf Aktiengesellschaft | Manufacture of acicular cobalt-containing magnetic iron oxide |
US4501774A (en) * | 1981-10-12 | 1985-02-26 | Ishihara Sangyo Kaisha, Ltd. | Process for the production of cobalt-containing magnetic iron oxide powder |
EP0158240A2 (en) * | 1984-04-12 | 1985-10-16 | BASF Aktiengesellschaft | Process for preparing isotrope magnetic cobalt containing iron oxides |
US4631140A (en) * | 1984-10-18 | 1986-12-23 | Basf Aktiengesellschaft | Ferrimagnetic particles and their preparation |
Families Citing this family (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5719049B2 (en) * | 1974-06-13 | 1982-04-20 | ||
DE2625106C2 (en) * | 1976-06-04 | 1982-03-11 | Bayer Ag, 5090 Leverkusen | Iron oxide black pigments with improved oxidation resistance and process for their preparation |
DE2705967C2 (en) * | 1977-02-12 | 1990-01-04 | Basf Ag, 6700 Ludwigshafen | Process for the production of acicular cobalt-containing magnetic iron oxide |
JPS5413997A (en) * | 1977-07-04 | 1979-02-01 | Sony Corp | Magnetic recording medium and its manufacture |
DE2743298A1 (en) * | 1977-09-27 | 1979-04-05 | Basf Ag | FERROMAGNETIC METAL PARTS CONSISTING MAINLY OF IRON AND THE PROCESS FOR THEIR PRODUCTION |
DE2815712A1 (en) * | 1978-04-12 | 1979-10-25 | Bayer Ag | IRON OXIDES FOR MAGNETIC SIGNAL RECORDING AND PROCESS FOR THEIR PRODUCTION |
US4276183A (en) * | 1978-10-25 | 1981-06-30 | Pfizer Inc. | Cobalt modified magnetic iron oxide |
DE2903593C3 (en) * | 1979-01-31 | 1982-05-06 | Bayer Ag, 5090 Leverkusen | Cobalt-doped ferrimagnetic iron oxides and processes for their production |
JPS55149137A (en) * | 1979-05-11 | 1980-11-20 | Tdk Corp | High performance high coercive force powder and its manufacture |
JPS5626729A (en) * | 1979-08-11 | 1981-03-14 | Tdk Corp | Powdered magnetic material for magnetic recording medium |
JPS5819733A (en) * | 1981-07-28 | 1983-02-04 | Toshiba Corp | Magnetic recording medium and its manufacture |
AU555302B2 (en) * | 1981-12-25 | 1986-09-18 | Ishihara Sangyo Kaisha Ltd. | Cobalt containing iron oxide powder |
JPS59107924A (en) * | 1982-12-08 | 1984-06-22 | Ishihara Sangyo Kaisha Ltd | Manufacture of magnetic iron oxide powder containing cobalt |
JPS6187302A (en) * | 1985-10-18 | 1986-05-02 | Sony Corp | Manufacture of magnetic recording medium |
DE3631193A1 (en) * | 1986-09-13 | 1988-03-24 | Bayer Ag | MAGNETIC IRON OXIDE PIGMENTS AND METHOD FOR THE PRODUCTION THEREOF |
DE3910782C2 (en) * | 1988-12-24 | 2003-08-28 | Toda Kogyo Corp | Process for the production of magnetic iron oxides and pigments thus obtained |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1592214C3 (en) * | 1967-11-25 | 1979-10-18 | Agfa-Gevaert Ag, 5090 Leverkusen | Process for the production of magnetic γ -Fe2 O3 by converting a -FeOOH particles |
NL7004295A (en) * | 1969-05-07 | 1970-11-10 |
-
1972
- 1972-09-01 DE DE19722243231 patent/DE2243231C2/en not_active Expired
-
1973
- 1973-08-30 JP JP9678673A patent/JPS5737532B2/ja not_active Expired
- 1973-08-31 GB GB4107273A patent/GB1432643A/en not_active Expired
- 1973-09-03 FR FR7331734A patent/FR2197818B3/fr not_active Expired
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4287233A (en) | 1979-02-13 | 1981-09-01 | Basf Aktiengesellschaft | Manufacture of acicular cobalt-containing magnetic iron oxide |
US4296149A (en) | 1979-02-13 | 1981-10-20 | Basf Aktiengesellschaft | Manufacture of acicular cobalt-containing magnetic iron oxide |
US4501774A (en) * | 1981-10-12 | 1985-02-26 | Ishihara Sangyo Kaisha, Ltd. | Process for the production of cobalt-containing magnetic iron oxide powder |
EP0158240A2 (en) * | 1984-04-12 | 1985-10-16 | BASF Aktiengesellschaft | Process for preparing isotrope magnetic cobalt containing iron oxides |
EP0158240A3 (en) * | 1984-04-12 | 1988-07-06 | BASF Aktiengesellschaft | Process for preparing isotrope magnetic cobalt containing iron oxides |
US4631140A (en) * | 1984-10-18 | 1986-12-23 | Basf Aktiengesellschaft | Ferrimagnetic particles and their preparation |
Also Published As
Publication number | Publication date |
---|---|
JPS4969588A (en) | 1974-07-05 |
JPS5737532B2 (en) | 1982-08-10 |
DE2243231A1 (en) | 1974-03-21 |
FR2197818A1 (en) | 1974-03-29 |
FR2197818B3 (en) | 1976-08-06 |
DE2243231C2 (en) | 1982-01-28 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB1432643A (en) | Manufacture of cobalt-modified ypsilon-iron-iii-oxides | |
US3931025A (en) | Magnetic iron oxides with improved orientability and a process for their production | |
GB1392980A (en) | Production of acicular magnetic iron oxides | |
US4400432A (en) | Coating iron oxide particles for magnetic recording | |
US4287233A (en) | Manufacture of acicular cobalt-containing magnetic iron oxide | |
GB1347615A (en) | Cobalt doped magnetic iron oxide particles | |
US4069367A (en) | Magnetic powder material comprising iron oxide particles with a copper-cobalt alloy coating | |
KR880001711B1 (en) | Manufacturing method of a magnetic substance | |
US4064292A (en) | Manufacture of cobalt-modified γ-iron(III)oxides | |
US4122216A (en) | Ferro-magnetic acicular particles for recording medium and process for preparing the same | |
GB1441183A (en) | Magnetic recording particles | |
GB1455616A (en) | Magnetic iron oxide pigments with orientability and a process for their production | |
US3902888A (en) | Process for preparing ferromagnetic alloy powder | |
US3977985A (en) | Magnetic recording medium comprising cobalt or cobalt alloy coated particles of spicular magnetite | |
GB644639A (en) | Improvements in or relating to magnetic materials | |
US4594267A (en) | Process for producing cobalt-containing magnetic iron oxide powder | |
GB1496890A (en) | Manufacture of magnetic materials which exhibit exchange anisotropy | |
US3243375A (en) | Precipitation process for preparing acicular magnetic metal oxide particles | |
GB1458623A (en) | Production of acicular cobalt-containing ferri-magnetic iron oxides | |
JPS62108737A (en) | Production of ferromagnetic iron oxide powder | |
US4664947A (en) | Multi-layer process for cobalt treatment of ferromagnetic oxides | |
GB1395704A (en) | Magnetic materials | |
GB1520756A (en) | Manufacture of gamma-iron (iii) oxide | |
US3654163A (en) | Cobalt ferrite magnetic powder for tape recording | |
JPS54122103A (en) | Magnetic recording medium and production of the same |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed | ||
PCNP | Patent ceased through non-payment of renewal fee |