• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    Acicular hyper-magnetite particles, that is, acicular particles of (FeO)xFe2O3 where x is greater than one and not greater than 1.5, are provided with coatings of a cobalt compound, the cobalt providing 1% to 10% of the total weight of the particles. The particles provide superior magnetic recording media.
    公开号:SU921474A3
    申请号:SU772537598
    申请日:1977-10-28
    公开日:1982-04-15
    发明作者:Марк Кантен Томас
    申请人:Миннесота Майнинг Энд Мануфакчуринг Компани (Фирма)；
    IPC主号:
    专利说明:

    The formation of closed shells is carried out to obtain a cobalt content of 1-10% of the weight of the hyper-magnetic particles, and after the formation of closed shells, they are fixed by heat treatment in an inert atmosphere at a temperature of 80-200 ° C. In this case, glyceride may be used as a reducing agent.
    The manufacture of magnetic particles of the working layer of the magnetic recording carrier occurs as follows.
    The alpha-FeOOH needle particles are reduced by heat treatment in an inert atmosphere in the presence of an organic reducing agent, such as glyceride, and the subsequent formation of closed shells on their surface by the application of a cobalt-containing material takes place. At the same time, the restoration of needle particles alpha-FeOOH is carried out during the time interval required for conversion to hyper-magnetic particles, and the formation of closed shells is performed until the cobalt content is equal to 10 of the weight of the hyper-magnetic particles. After the formation of closed shells, heat treatment is performed in an inert atmosphere at 200 ° C,
    The use of the invention makes it possible to significantly reduce the instability of the parameters of the working layer of a magnetic recording medium obtained from magnetic particles produced in accordance with it.
    权利要求:
    Claims (2)
    [1]
    1. A method of making magnetic particles of a working layer of a magnetic recording medium by restoring the needle-like alpha-FeOOH particles by heat treatment in an inert medium in the presence of a reducing agent at a temperature of 300-600 ° C and the subsequent formation of cobalt-containing material on their surface, characterized in that , in order to reduce the instability of the parameters of the working layer of the carrier magnetic
    recordings, the restoration of needle particles alpha-geon will be performed during the time interval required for their transformation into hyper-magnetic particles, the formation of closed shells is carried out until a cobalt content of 1-10 by weight of the hyper-magnetic particles is obtained, and after the formation of closed shells
    made by heat treatment in an inert atmosphere at a temperature of 80-200 ° C.
    [2]
    2. The method according to claim 1, characterized in that a glyceride is used as a reducing agent.
    Sources of information taken into account in the examination
    1. Japan No. iS-AOtO, class, 62 B 7 21.12.73.
    2. Japanese Patent No. 48-1099, cl. 62 В 7. 09.OA.73 (prototype).
    类似技术:
    公开号 | 公开日 | 专利标题
    SU921474A3|1982-04-15|Method of manufacturing magnetic particles of the working layer of magnetic record carrier
    JPS52122213A|1977-10-14|Production of ferromagnetic metal powder
    DE2608022C2|1984-03-29|Process for the production of magnetic recording media with a wear-resistant surface
    JPS5668928A|1981-06-09|Magnetic recording medium
    JPS5240304A|1977-03-29|Manufacturing method of magnetic recording medium
    DE3031768A1|1981-03-26|METHOD FOR PRODUCING FINE METAL PARTICLES
    JPS5316605A|1978-02-15|Improved magnetic recording medium
    JPS5433041A|1979-03-10|Thermal magnetic recording method
    SU881840A1|1981-11-15|Method of making suspension for magnetic record carrier working layer
    JPS59127235A|1984-07-23|Vertical magnetic recording medium
    JPS6199922A|1986-05-19|Magnetic recording medium
    JPS5573803A|1980-06-03|Production of magnetic alloy powder
    JPS6083222A|1985-05-11|Magnetic recording medium
    JPS5332707A|1978-03-28|Magnetic recording/reproducing apparatus and its manufacture
    JPS6452002A|1989-02-28|Acicular magnetized metal fine powder having excellent dispersion and its production
    SU568969A1|1977-08-15|Binder for working coating of magnetic record carrier
    SU712836A1|1980-01-30|Magnetic record carrier working layer
    JPS529900A|1977-01-25|Manufacturing method of ferromagnetic metallic powder
    SU911604A1|1982-03-07|Method of making magnetic lacquer for magnetic record carrier working layer
    SU525154A1|1976-08-15|Method of making magnetic recording medium
    JPS5216202A|1977-02-07|Manufacturing method of magnetic recording medium
    JPS5613527A|1981-02-09|Magnetic recording medium
    SU940219A1|1982-06-30|Method of producing magnetic particles of magnetic record carrier sensitive layer
    SU593239A1|1978-02-15|Magnetic head unit
    JPS6083221A|1985-05-11|Magnetic recording medium
    同族专利:
    公开号 | 公开日
    FR2369214B1|1984-06-29|
    AU514316B2|1981-02-05|
    JPS5360399A|1978-05-30|
    NL7711724A|1978-05-03|
    IT1090198B|1985-06-18|
    BR7707242A|1978-08-08|
    DE2749010A1|1978-05-11|
    ATA771777A|1981-05-15|
    AR214343A1|1979-05-31|
    DE2749010C2|1983-01-20|
    NL188483B|1992-02-03|
    AT365356B|1982-01-11|
    BE860291A|1978-04-28|
    NL188483C|1992-07-01|
    GB1594727A|1981-08-05|
    AU2969177A|1979-04-26|
    FR2369214A1|1978-05-26|
    CA1097057A|1981-03-10|
    ZA775470B|1978-07-26|
    US4137342A|1979-01-30|
    JPS5852927B2|1983-11-26|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    JPS5029157B1|1971-05-27|1975-09-20|
    JPS5225959B2|1972-01-13|1977-07-11|
    US3977985A|1972-02-23|1976-08-31|Tdk Electronics Company, Limited|Magnetic recording medium comprising cobalt or cobalt alloy coated particles of spicular magnetite|
    US3932293A|1972-05-22|1976-01-13|Minnesota Mining And Manufacturing Company|Metallic ferromagnetic particles for use in environmentally stable magnetic recording media|
    US4064292A|1972-09-01|1977-12-20|Badische Anilin- & Soda-Fabrik, Aktiengesellschaft|Manufacture of cobalt-modified γ-ironoxides|
    JPS5321118B2|1973-03-05|1978-06-30|
    JPS5242363B2|1973-03-20|1977-10-24|
    US4010310A|1973-03-20|1977-03-01|Tdk Electronics Company, Limited|Magnetic powder|
    JPS5133758A|1974-09-17|1976-03-23|Fuji Photo Film Co Ltd|
    JPS608606B2|1975-07-02|1985-03-04|Fuji Photo Film Co Ltd|
    JPS5853493B2|1975-07-02|1983-11-29|Fuji Photo Film Co Ltd|US4364988A|1978-07-31|1982-12-21|Hitachi Maxell, Ltd.|Magnetic recording medium|
    JPS6348810B2|1979-05-11|1988-09-30|Tdk Electronics Co Ltd|
    JPS5626729A|1979-08-11|1981-03-14|Tdk Corp|Powdered magnetic material for magnetic recording medium|
    EP0076142B1|1981-09-28|1987-09-16|Xerox Corporation|Post treatment of perpendicular magnetic recording media|
    US4388367A|1981-09-28|1983-06-14|Xerox Corporation|Perpendicular magnetic recording medium and fabrication|
    US4501774A|1981-10-12|1985-02-26|Ishihara Sangyo Kaisha, Ltd.|Process for the production of cobalt-containing magnetic iron oxide powder|
    DE3143870A1|1981-11-05|1983-05-11|Basf Ag, 6700 Ludwigshafen|METHOD FOR PRODUCING NEEDLE-SHAPED, FERRIMAGNETIC IRON OXIDES|
    DE3224325A1|1982-06-30|1984-01-05|Basf Ag, 6700 Ludwigshafen|METHOD FOR PRODUCING NEEDLE-SHAPED, FERRIMAGNETIC IRON OXIDES|
    US5151206A|1983-04-25|1992-09-29|Daikin Industries, Ltd.|Acicular iron carbide particulate material and process for producing same|
    US4842759A|1983-04-25|1989-06-27|Daikin Industries, Ltd.|Acicular process for producing particulate material|
    JPS60143431A|1983-12-29|1985-07-29|Alps Electric Co Ltd|Recording medium for vertical magnetic recording|
    US5219554A|1986-07-03|1993-06-15|Advanced Magnetics, Inc.|Hydrated biodegradable superparamagnetic metal oxides|
    US5069216A|1986-07-03|1991-12-03|Advanced Magnetics Inc.|Silanized biodegradable super paramagnetic metal oxides as contrast agents for imaging the gastrointestinal tract|
    US4814546A|1987-11-25|1989-03-21|Minnesota Mining And Manufacturing Company|Electromagnetic radiation suppression cover|
    US5106437A|1987-11-25|1992-04-21|Minnesota Mining And Manufacturing Company|Electromagnetic radiation suppression cover|
    US6030695A|1996-03-28|2000-02-29|Imation Corp.|Coated magnetic recording medium, paint for coated magnetic medium and method for producing coated magnetic medium|
    US5932330A|1993-09-30|1999-08-03|Imation Corp.|Coated magnetic recording medium, paint for coated magnetic medium and method for producing coated magnetic medium|
    WO1996013461A1|1994-10-31|1996-05-09|Minnesota Mining And Manufacturing Company|Method of producing magnetic iron oxide|
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    US05/736,744|US4137342A|1976-10-29|1976-10-29|Cobalt-doped acicular hyper-magnetite particles|
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