JPS56159839A - Magnetic recording medium - Google Patents

Magnetic recording medium

Info

Publication number
JPS56159839A
JPS56159839A JP6230880A JP6230880A JPS56159839A JP S56159839 A JPS56159839 A JP S56159839A JP 6230880 A JP6230880 A JP 6230880A JP 6230880 A JP6230880 A JP 6230880A JP S56159839 A JPS56159839 A JP S56159839A
Authority
JP
Japan
Prior art keywords
iron oxide
magnetic
backing material
magnetic recording
powder
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.)
Pending
Application number
JP6230880A
Other languages
Japanese (ja)
Inventor
Yasutaro Kamisaka
Sanehiro Kudo
Hideo Fujiwara
Masahiro Amamiya
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.)
Hitachi Ltd
Maxell Holdings Ltd
Original Assignee
Hitachi Ltd
Hitachi Maxell Ltd
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 Hitachi Ltd, Hitachi Maxell Ltd filed Critical Hitachi Ltd
Priority to JP6230880A priority Critical patent/JPS56159839A/en
Publication of JPS56159839A publication Critical patent/JPS56159839A/en
Pending 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
    • G11B5/712—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 surface treatment or coating of magnetic particles

Abstract

PURPOSE:To form a medium suitable for vertical magnetic recording by using ferromagnetic iron oxide powder formed with iron oxide layers contg. cobalt on the surface parts thereof. CONSTITUTION:Granular ferromagnetic iron oxide (e.g.; gamma-Fe2O3, magnetite, etc.) is dispersed in a soln. containing a bivalent cobalt salt (may be used in combination with a bivalent iron salt) and an alkali and this is heated in a nonoxidation atmosphere, where iron oxide layers containing cobalt are formed on the surface layers of ferromagnetic iron oxide powder. Next, the resultant magnetic powder and a binder are mixed to form a magnetic coating. Thence, while a magnetic field is being applied vertically to the surface of a nonmagnetic backing material, the magnetic coating is applied on the surface of the backing material, and the easy magnetization axis of the magnetic powder is oriented perpendicularly to the surface of the backing material, whereby the vertical magnetic recording medium is obtained.
JP6230880A 1980-05-13 1980-05-13 Magnetic recording medium Pending JPS56159839A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6230880A JPS56159839A (en) 1980-05-13 1980-05-13 Magnetic recording medium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6230880A JPS56159839A (en) 1980-05-13 1980-05-13 Magnetic recording medium

Publications (1)

Publication Number Publication Date
JPS56159839A true JPS56159839A (en) 1981-12-09

Family

ID=13196369

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6230880A Pending JPS56159839A (en) 1980-05-13 1980-05-13 Magnetic recording medium

Country Status (1)

Country Link
JP (1) JPS56159839A (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5484300A (en) * 1977-12-19 1979-07-05 Hitachi Maxell Method of producing magnetic powder
JPS54145106A (en) * 1978-04-30 1979-11-13 Hitachi Maxell Magnetic recording medium

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5484300A (en) * 1977-12-19 1979-07-05 Hitachi Maxell Method of producing magnetic powder
JPS54145106A (en) * 1978-04-30 1979-11-13 Hitachi Maxell Magnetic recording medium

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