GB1395704A - Magnetic materials - Google Patents

Magnetic materials

Info

Publication number
GB1395704A
GB1395704A GB1157071A GB1157071A GB1395704A GB 1395704 A GB1395704 A GB 1395704A GB 1157071 A GB1157071 A GB 1157071A GB 1157071 A GB1157071 A GB 1157071A GB 1395704 A GB1395704 A GB 1395704A
Authority
GB
United Kingdom
Prior art keywords
alkali metal
feo
oxidation
salt solution
ferrous salt
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
GB1157071A
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.)
Eastman Kodak Co
Original Assignee
Eastman Kodak Co
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 Eastman Kodak Co filed Critical Eastman Kodak Co
Priority to GB1157071A priority Critical patent/GB1395704A/en
Publication of GB1395704A publication Critical patent/GB1395704A/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
    • G11B5/70678—Ferrites
    • G11B5/70684—Ferro-ferrioxydes
    • 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)
    • 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
    • C01G49/08—Ferroso-ferric oxide (Fe3O4)
    • 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
    • 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
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/50—Solid solutions
    • C01P2002/52—Solid solutions containing elements as dopants
    • C01P2002/54—Solid solutions containing elements as dopants one element only
    • 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
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
    • 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
    • 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
    • C01P2006/80—Compositional purity

Abstract

1395704 Magnetic materials EASTMAN KODAK CO 1 May 1972 [27 April 1971] 11570/71 Heading C1A Fe 3 O 4 and γ-Fe 2 O 3 crystalline particles with a minimum acicularity ratio not below 15 and with a basicity of at least 0À04 meq./g. due to alkali metal ions are claimed per se. The alkali metal may be Na or K. The crystalline particles may be not more than 0À8 microns in length and have a coefficient of polydispersion higher than 2. They may also contain Co, Ni, Cr, Zn, Cd and/or Mn; they may contain alkaline earth metal ions situated mainly on the surface. α-FeO.OH may be made from a ferrous salt solution by precipitation with excess alkali metal hydroxide followed by oxidation and boiling, the ferrous salt solution may be added to the hydroxide solution by the method of Specification 1,328,115. γ-Fe 2 O 3 may be made from suitable α-FeO.OH by dehydration, reduction to Fe 3 O 4 and oxidation. The prducts are suitable for the production of magnetic recording materials.
GB1157071A 1971-04-27 1971-04-27 Magnetic materials Expired GB1395704A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1157071A GB1395704A (en) 1971-04-27 1971-04-27 Magnetic materials

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1157071A GB1395704A (en) 1971-04-27 1971-04-27 Magnetic materials

Publications (1)

Publication Number Publication Date
GB1395704A true GB1395704A (en) 1975-05-29

Family

ID=9988671

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1157071A Expired GB1395704A (en) 1971-04-27 1971-04-27 Magnetic materials

Country Status (1)

Country Link
GB (1) GB1395704A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4167582A (en) * 1976-08-27 1979-09-11 Victor Company Of Japan, Limited Magnetic metallic powder containing iron and magnetic recording medium using same powder
DE3103989A1 (en) * 1980-02-05 1981-11-26 Mitsui Toatsu Chemicals, Inc., Tokyo "METHOD FOR PRODUCING PARTICLES OF AN IRON COMPOUND FOR USE IN MAGNETIC RECORDING"
FR2487326A1 (en) * 1980-07-24 1982-01-29 Kodak Pathe PROCESS FOR THE PREPARATION OF ACIDIC PARTICLES OF MAGNETIC IRON OXIDE
EP0045246A1 (en) * 1980-07-24 1982-02-03 EASTMAN KODAK COMPANY (a New Jersey corporation) Process for preparing acicular iron oxide particles
US4323596A (en) * 1978-04-12 1982-04-06 Bayer Aktiengesellschaft Coating iron oxide particles for magnetic recording
FR2513419A1 (en) * 1981-09-24 1983-03-25 Hitachi Maxell MAGNETIC RECORDING MEDIUM AND METHOD FOR PRODUCING THE SAME
EP0191998A1 (en) * 1985-02-19 1986-08-27 Kodak-Pathe Process for preparing facetted nodular particles and isotropic magnetic recording elements containing such particles

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4167582A (en) * 1976-08-27 1979-09-11 Victor Company Of Japan, Limited Magnetic metallic powder containing iron and magnetic recording medium using same powder
US4323596A (en) * 1978-04-12 1982-04-06 Bayer Aktiengesellschaft Coating iron oxide particles for magnetic recording
US4400432A (en) * 1978-04-12 1983-08-23 Bayer Aktiengesellschaft Coating iron oxide particles for magnetic recording
DE3103989A1 (en) * 1980-02-05 1981-11-26 Mitsui Toatsu Chemicals, Inc., Tokyo "METHOD FOR PRODUCING PARTICLES OF AN IRON COMPOUND FOR USE IN MAGNETIC RECORDING"
EP0045246A1 (en) * 1980-07-24 1982-02-03 EASTMAN KODAK COMPANY (a New Jersey corporation) Process for preparing acicular iron oxide particles
WO1982000287A1 (en) * 1980-07-24 1982-02-04 Kodak Co Eastman Process for preparing acicular iron oxide particles
US4376714A (en) 1980-07-24 1983-03-15 Eastman Kodak Company Process for preparing acicular iron oxide particles
FR2487326A1 (en) * 1980-07-24 1982-01-29 Kodak Pathe PROCESS FOR THE PREPARATION OF ACIDIC PARTICLES OF MAGNETIC IRON OXIDE
FR2513419A1 (en) * 1981-09-24 1983-03-25 Hitachi Maxell MAGNETIC RECORDING MEDIUM AND METHOD FOR PRODUCING THE SAME
EP0075991A2 (en) * 1981-09-24 1983-04-06 Hitachi Maxell Ltd. Magnetic recording medium and method for the production thereof
EP0075991A3 (en) * 1981-09-24 1984-09-26 Hitachi Maxell Ltd. Magnetic recording medium and method for the production thereof
EP0191998A1 (en) * 1985-02-19 1986-08-27 Kodak-Pathe Process for preparing facetted nodular particles and isotropic magnetic recording elements containing such particles
WO1986005026A1 (en) * 1985-02-19 1986-08-28 Kodak-Pathe Facetted nodular particles, their preparation and use

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Legal Events

Date Code Title Description
PS Patent sealed
PCNP Patent ceased through non-payment of renewal fee