GB1221434A - PROCESS FOR THE PRODUCTION OF HIGHLY COERCIVE NEEDLE-SHAPED gamma-Fe2O3 AND MAGNETIC RECORDING MEMBERS PREPARED THEREWITH - Google Patents

PROCESS FOR THE PRODUCTION OF HIGHLY COERCIVE NEEDLE-SHAPED gamma-Fe2O3 AND MAGNETIC RECORDING MEMBERS PREPARED THEREWITH

Info

Publication number
GB1221434A
GB1221434A GB619668A GB619668A GB1221434A GB 1221434 A GB1221434 A GB 1221434A GB 619668 A GB619668 A GB 619668A GB 619668 A GB619668 A GB 619668A GB 1221434 A GB1221434 A GB 1221434A
Authority
GB
United Kingdom
Prior art keywords
feooh
nuclei
fe2o3
needle
production
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
Application number
GB619668A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bayer AG
Original Assignee
Bayer AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Bayer AG filed Critical Bayer AG
Publication of GB1221434A publication Critical patent/GB1221434A/en
Expired legal-status Critical Current

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
    • G11B5/70663—Preparation processes specially adapted therefor, e.g. using stabilising agents
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G49/00—Compounds of iron
    • C01G49/02—Oxides; Hydroxides
    • C01G49/06—Ferric oxide (Fe2O3)
    • 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
    • G11B5/70657—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 with a skin
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/10—Particle morphology extending in one dimension, e.g. needle-like
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/54—Particles characterised by their aspect ratio, i.e. the ratio of sizes in the longest to the shortest dimension
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/42—Magnetic properties

Abstract

1,221,434. αFeOOH; γFe 2 O 3 . FARBENFABRIKEN BAYER A.G. 8 Feb., 1968 [8 Feb., 1967], No. 6196/68. Heading C1A. [Also in Division H1] A circular α-FeOOH, which is subsequently dehydrated, reduced, and re-oxidized to γ- Fe 2 O 3 , is obtained by precipitation in the presence of α-FeOOH nuclei from a ferrous salt solution by the addition of an oxidizing agent, at a pH of 2-6, a temperature of 40- 150‹ C., and an α-FeOOH formation rate of 0À5-15 g./l./hr., precipitation being effected by addition of a base or substance which forms ammonia in situ. The solution may contain FeSO 4 or FeCl 2 at a concentration of 1-150g./l. The oxidizing agent may be O 2 , air, or nitrobenzene. The precipitating agent may be an alkali metal or alkaline earth metal hydroxide or carbonate, e.g. NaOH or Na 2 CO 3 , or gaseous NH 3 , hexamethylene, tetramine, or urea. The nuclei may be formed by preciptating Fe(OH) 2 rapidly from FeSO 4 with NaOH, then oxidizing to α-FeOOH with air. 2-40 g./l. of nuclei may be used. The acicular α-FeOOH has a length : width ratio from 15 : 1 to 5 :1, which is preserved in the γ-Fe 2 O 3 . The α- FeOOH may be dehydrated to α-Fe 2 O 3 at 400‹ C., reduced to Fe 3 O 4 in H 2 and steam at 400‹ C., cooled in N 2 , and oxidized to γ-Fe 2 O 3 in O 2 at 250‹ C.
GB619668A 1967-02-08 1968-02-08 PROCESS FOR THE PRODUCTION OF HIGHLY COERCIVE NEEDLE-SHAPED gamma-Fe2O3 AND MAGNETIC RECORDING MEMBERS PREPARED THEREWITH Expired GB1221434A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEF0051456 1967-02-08

Publications (1)

Publication Number Publication Date
GB1221434A true GB1221434A (en) 1971-02-03

Family

ID=7104621

Family Applications (1)

Application Number Title Priority Date Filing Date
GB619668A Expired GB1221434A (en) 1967-02-08 1968-02-08 PROCESS FOR THE PRODUCTION OF HIGHLY COERCIVE NEEDLE-SHAPED gamma-Fe2O3 AND MAGNETIC RECORDING MEMBERS PREPARED THEREWITH

Country Status (3)

Country Link
JP (1) JPS4822915B1 (en)
DE (1) DE1592398A1 (en)
GB (1) GB1221434A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2230590A1 (en) * 1973-05-22 1974-12-20 Bayer Ag
FR2376195A1 (en) * 1977-01-11 1978-07-28 Euteco Spa PROCESS FOR THE PREPARATION OF IRON HYDROXIDE PIGMENT
FR2376889A1 (en) * 1977-01-11 1978-08-04 Euteco Spa PROCESS FOR PREPARING A RED IRON OXIDE PIGMENT
EP0024693A2 (en) * 1979-09-01 1981-03-11 BASF Aktiengesellschaft Process for the preparation of acicular ferrimagnetic iron oxide, and its application
EP0045028A2 (en) * 1980-07-29 1982-02-03 Bayer Ag Process for the preparation of magnetic iron oxides
FR2517292A1 (en) * 1981-11-27 1983-06-03 Ishihara Mining & Chemical Co PROCESS FOR THE PREPARATION OF ACICULAR A-FEOOH FOR MAGNETIC RECORDING MATERIAL
WO1996029288A1 (en) * 1995-03-22 1996-09-26 Pers Kemi As Method of producing alpha-hematite hydrate from galvanising sludge
CN101913656A (en) * 2010-08-09 2010-12-15 铜陵瑞莱科技有限公司 Method for preparing iron oxide yellow pigment by using titanium white by-product of ferrous sulfate

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3974079A (en) * 1971-05-06 1976-08-10 Bayer Aktiengesellschaft Production of gamma iron oxide
DE3228669A1 (en) * 1982-07-31 1984-02-02 Basf Ag, 6700 Ludwigshafen METHOD FOR PRODUCING NEEDLE-SHAPED FERROMAGNETIC METAL PARTICLES, ESSENTIALLY IRON
CN106904657B (en) * 2017-03-21 2018-08-17 安徽师范大学 FeOOH nano-particle of size adjustable and preparation method thereof

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2230590A1 (en) * 1973-05-22 1974-12-20 Bayer Ag
FR2376195A1 (en) * 1977-01-11 1978-07-28 Euteco Spa PROCESS FOR THE PREPARATION OF IRON HYDROXIDE PIGMENT
FR2376889A1 (en) * 1977-01-11 1978-08-04 Euteco Spa PROCESS FOR PREPARING A RED IRON OXIDE PIGMENT
EP0024693A2 (en) * 1979-09-01 1981-03-11 BASF Aktiengesellschaft Process for the preparation of acicular ferrimagnetic iron oxide, and its application
EP0024693A3 (en) * 1979-09-01 1981-03-18 Basf Aktiengesellschaft Process for the preparation of acicular ferrimagnetic iron oxide, and its application
EP0045028A2 (en) * 1980-07-29 1982-02-03 Bayer Ag Process for the preparation of magnetic iron oxides
EP0045028A3 (en) * 1980-07-29 1983-09-07 Bayer Ag Process for the preparation of magnetic iron oxides
FR2517292A1 (en) * 1981-11-27 1983-06-03 Ishihara Mining & Chemical Co PROCESS FOR THE PREPARATION OF ACICULAR A-FEOOH FOR MAGNETIC RECORDING MATERIAL
WO1996029288A1 (en) * 1995-03-22 1996-09-26 Pers Kemi As Method of producing alpha-hematite hydrate from galvanising sludge
CN101913656A (en) * 2010-08-09 2010-12-15 铜陵瑞莱科技有限公司 Method for preparing iron oxide yellow pigment by using titanium white by-product of ferrous sulfate

Also Published As

Publication number Publication date
JPS4822915B1 (en) 1973-07-10
DE1592398A1 (en) 1970-12-17

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