JPH0269904A - Manufacture of modified magnetic metal powder - Google Patents
Manufacture of modified magnetic metal powderInfo
- Publication number
- JPH0269904A JPH0269904A JP63221953A JP22195388A JPH0269904A JP H0269904 A JPH0269904 A JP H0269904A JP 63221953 A JP63221953 A JP 63221953A JP 22195388 A JP22195388 A JP 22195388A JP H0269904 A JPH0269904 A JP H0269904A
- Authority
- JP
- Japan
- Prior art keywords
- metal powder
- magnetic metal
- powder
- oxidation
- graphite
- 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
Links
- 239000000843 powder Substances 0.000 title claims abstract description 62
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 58
- 239000002184 metal Substances 0.000 title claims abstract description 58
- 238000004519 manufacturing process Methods 0.000 title claims description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 16
- 239000010439 graphite Substances 0.000 claims abstract description 16
- 238000000576 coating method Methods 0.000 claims abstract description 11
- 239000011248 coating agent Substances 0.000 claims abstract description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 7
- 239000004215 Carbon black (E152) Substances 0.000 claims abstract description 6
- 229930195733 hydrocarbon Natural products 0.000 claims abstract description 6
- 150000002430 hydrocarbons Chemical class 0.000 claims abstract description 6
- 238000006243 chemical reaction Methods 0.000 claims description 10
- 230000003647 oxidation Effects 0.000 abstract description 15
- 238000007254 oxidation reaction Methods 0.000 abstract description 15
- 238000000034 method Methods 0.000 abstract description 14
- 230000005415 magnetization Effects 0.000 abstract description 11
- 229910052742 iron Inorganic materials 0.000 abstract description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 abstract description 4
- 229910045601 alloy Inorganic materials 0.000 abstract description 3
- 239000000956 alloy Substances 0.000 abstract description 3
- 239000002245 particle Substances 0.000 abstract description 3
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 abstract description 2
- 229910052759 nickel Inorganic materials 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 12
- 238000011282 treatment Methods 0.000 description 11
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 8
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 7
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 6
- 229910052799 carbon Inorganic materials 0.000 description 6
- 230000002265 prevention Effects 0.000 description 6
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 4
- 239000001257 hydrogen Substances 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- 230000003197 catalytic effect Effects 0.000 description 3
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000005416 organic matter Substances 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 1
- 230000003064 anti-oxidating effect Effects 0.000 description 1
- 150000001721 carbon Chemical class 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 229910002090 carbon oxide Inorganic materials 0.000 description 1
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- -1 e203 Chemical compound 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000005755 formation reaction Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- UCNNJGDEJXIUCC-UHFFFAOYSA-L hydroxy(oxo)iron;iron Chemical compound [Fe].O[Fe]=O.O[Fe]=O UCNNJGDEJXIUCC-UHFFFAOYSA-L 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 229910052809 inorganic oxide Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 239000011553 magnetic fluid Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 238000011369 optimal treatment Methods 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 238000000197 pyrolysis Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical group 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
- 229910006297 γ-Fe2O3 Inorganic materials 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
- H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
- H01F1/06—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder
- H01F1/061—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys in the form of particles, e.g. powder with a protective layer
Abstract
Description
【発明の詳細な説明】
〔発明の背景〕
（産業上の利用分野）
本発明は、主に磁気記録用途に好適な耐久性および分散
性に優れた改質磁性金属粉末の製造法に関する。DETAILED DESCRIPTION OF THE INVENTION [Background of the Invention] (Industrial Application Field) The present invention relates to a method for producing a modified magnetic metal powder with excellent durability and dispersibility, which is mainly suitable for magnetic recording applications.
（従来の技術）
近年、磁気記録の高密度化の要求に伴い、記録媒体とし
て従来用いられていたγ−Ｆｅ２Ｏ３、Ｃｏ被被着−Ｆ
ｅ２０３などの酸化鉄に代り、高保磁力と高残留磁化を
有する鉄または鉄を主体とする合金の磁性金属粉末が、
実用化されている。(Prior art) In recent years, with the demand for higher density magnetic recording, γ-Fe2O3, Co-coated -F, which has been conventionally used as a recording medium,
Instead of iron oxide such as e203, magnetic metal powder of iron or an iron-based alloy with high coercive force and high residual magnetization is used.
It has been put into practical use.
この磁性金属粉末は、表面の活性が高いので、空気中で
激しく酸化されて磁気特性が急激に劣化する性質を有す
るため、そのまま磁性塗料の原料として使用することは
できない。そこで、磁性金属粉末の急激な酸化を防止す
ることを目的とした防錆処理手段が従来からいくつか提
案されている。Since this magnetic metal powder has a highly active surface, it has the property of being violently oxidized in the air and rapidly deteriorating its magnetic properties, so it cannot be used as is as a raw material for magnetic paint. Therefore, several anti-rust treatment methods have been proposed for the purpose of preventing rapid oxidation of magnetic metal powder.
このうち、通常用いられている方法は、金属粉末の表面
を徐々に酸化させて、酸化膜で覆うことにより、金属粉
末内部の急激な酸化を防止する方法（徐酸化法）であり
、例えば、金属粉末を有機溶剤中に懸濁させ、５０〜９
０℃に加温した状態で溶液中に酸素を含むガスを吹き込
み、これを金属粉末の表面に溶液中で接触させて酸化膜
を形成させる方法が知られている。Among these methods, the commonly used method is to gradually oxidize the surface of the metal powder and cover it with an oxide film to prevent rapid oxidation inside the metal powder (slow oxidation method). Metal powder is suspended in an organic solvent, and 50-9
A method is known in which an oxygen-containing gas is blown into a solution heated to 0° C., and the gas is brought into contact with the surface of metal powder in the solution to form an oxide film.
しかし、上記の処理方法は、酸化処理によって磁性金属
粉末の一部が非磁性の酸化物に変わるため、個々の磁性
金属粉末の磁性特性が酸化処理前に比べ゛Ｃ劣化すると
いう欠点かあった。具体的には、例えば、形成させた鉄
粉を、」１記従来の方法によって防錆処理すると、飽和
磁化σＳは２０〜５０％低下してしまう。However, the above treatment method had the disadvantage that the magnetic properties of each magnetic metal powder deteriorated by C compared to before the oxidation treatment, as a part of the magnetic metal powder was converted into a non-magnetic oxide by the oxidation treatment. . Specifically, for example, if the formed iron powder is subjected to rust prevention treatment by the conventional method described in 1., the saturation magnetization σS will decrease by 20 to 50%.
また、他の防錆処理方法として、有機または無機物の表
面処理が行なわれている。しが腰有機物処理は初期の一
定期間の耐蝕性を増すことは出来ても、長期の使用では
有機物は耐久性がない為有効でなく、最適なものは見つ
かっていない。また、Ｓ ｉ Ｏ２やＡ １２０３を主
体とする無機の酸化物の被覆法も実用化されているが、
表面での吸着が不均一になるためこれらは分散性向上に
は有効であっても防錆処理としては殆んど役に立つこと
はなかった。In addition, as another rust prevention treatment method, surface treatment with organic or inorganic substances is performed. Although organic matter treatment can increase corrosion resistance for an initial period of time, it is not effective in long-term use because organic matter is not durable, and the optimal treatment has not yet been found. Additionally, coating methods with inorganic oxides mainly composed of SiO2 and A1203 have been put into practical use;
Since adsorption on the surface becomes non-uniform, although these are effective for improving dispersibility, they are of little use as anti-rust treatment.
（要 旨）
本発明は、」１記従来技術の問題点を解決するためにな
されたもので、その目的は、磁性金属粉末の表面に酸化
膜を形成させずに飽和磁化σＳの低下を防ぐことができ
る防錆方法を提供することにある。(Summary) The present invention was made in order to solve the problems of the prior art described in 1. The purpose is to prevent the decrease in saturation magnetization σS without forming an oxide film on the surface of magnetic metal powder. The purpose is to provide a rust prevention method that can prevent rust.
すなわち、本発明による改質磁性金属粉の製造法は、磁
性金属粉末に炭化水素ガスまたは水性ガスを接触させて
反応させることによって、該磁性金属粉末の表面に黒鉛
被膜を形成させること、を特徴とするものである。That is, the method for producing modified magnetic metal powder according to the present invention is characterized in that a graphite film is formed on the surface of the magnetic metal powder by bringing the magnetic metal powder into contact with hydrocarbon gas or water gas and causing a reaction. That is.
（効 果）
本発明は磁性金属粉表面の触媒作用を巧みに利用したも
のであって、炭化水素または水性ガスを原金属粉末表面
に接触させてこれを分解させて該金属粉末の表面に緻密
な黒鉛膜を形成させる。この黒鉛被膜により徐酸化法の
欠点である飽和磁化σＳの大幅な低下が抑制され、かつ
酸化防止性能か付与された改質磁性金属粉末が得られる
。(Effects) The present invention skillfully utilizes the catalytic action of the surface of magnetic metal powder, and brings hydrocarbon or water gas into contact with the surface of the raw metal powder to decompose it and form a dense layer on the surface of the metal powder. Forms a graphite film. This graphite coating suppresses a significant decrease in saturation magnetization σS, which is a drawback of the slow oxidation method, and provides a modified magnetic metal powder that has anti-oxidation properties.
原磁性金属粉末
本発明で使用される磁性金属粉末としては、金属酸化物
粉末を還元して得られる金属粉末、不活性ガス中で金属
を蒸発させて得られる金属粉末、金属カルボニルを熱分
解して得られる金属粉末、その他がある。これら磁性金
属粉末は、Ｆｅ。Original magnetic metal powder The magnetic metal powder used in the present invention includes metal powder obtained by reducing metal oxide powder, metal powder obtained by evaporating metal in an inert gas, and metal powder obtained by thermally decomposing metal carbonyl. There are metal powders obtained by These magnetic metal powders are Fe.
Ｃｏ、Ｎｉ等の遷移金属またはこれらの合金であり、粒
子径としては１ミクロン以下、好ましくは０、 ５ミク
ロン以下、のちのが適当である。It is a transition metal such as Co, Ni, or an alloy thereof, and the particle size is preferably 1 micron or less, preferably 0.5 micron or less, or later.
黒鉛被覆
本発明の金属粉末への黒鉛被膜形成の反応条件は、水性
ガス（すなわち−酸化炭素と水素の混合ガス）使用の場
合には、これを反応温度１００〜６００℃、好ましくは
１．５０〜４００℃、の範囲で金属粉末に接触させ、金
属粉末の触媒作用によってＣＯ十Ｈ２→Ｃ（黒鉛）＋Ｈ
２０の反応で表面に酸化防止に有効な黒鉛被膜を形成さ
せる。また、炭化水素ガスを使用する場合には、メタン
、エタン、ベンゼン、トルエン等の処理温度で気体とな
りつる炭化水素をガスとして、例えば、水素気流中で、
反応温度３００〜６００℃、好ましくは３００〜５００
℃、の範囲で原磁性金属粉末と接触させる。Graphite Coating The reaction conditions for forming a graphite coating on the metal powder of the present invention are as follows: When using a water gas (i.e., a mixed gas of carbon oxide and hydrogen), the reaction temperature is 100 to 600°C, preferably 1.50°C. Contact with metal powder in the range of ~400℃, CO + H2 → C (graphite) + H due to the catalytic action of the metal powder.
The reaction in step 20 forms a graphite film on the surface that is effective in preventing oxidation. In addition, when using a hydrocarbon gas, a hydrocarbon that becomes a gas at the processing temperature of methane, ethane, benzene, toluene, etc. is used as a gas, for example, in a hydrogen stream.
Reaction temperature 300-600°C, preferably 300-500°C
℃, in contact with the original magnetic metal powder.
」４記いずれの反応においても反応温度が６００℃超過
では黒鉛の形成反応の他に金属粉間の焼結が起こって磁
気特性が低下する傾向があるので好ましくない。In any of the reactions described in Section 4, if the reaction temperature exceeds 600° C., sintering between metal powders occurs in addition to the graphite formation reaction, which tends to deteriorate the magnetic properties, which is not preferable.
金属粉末に対して酸化防止に有効な黒鉛被覆量は、金属
粉末に対して０．２〜２０重量％の範囲、好ましくは０
． ５〜１５重量％の範囲、が適当である。The amount of graphite coating that is effective for preventing oxidation on metal powder is in the range of 0.2 to 20% by weight, preferably 0.
．． A range of 5 to 15% by weight is suitable.
改質磁性金属粉末
上記方法で得られる改質磁性金属粉末は、金属粉末表面
の触媒作用により形成されて緻密な黒鉛被膜により、飽
和磁化σＳの低下が微少であって、実用的に充分な酸化
防止の耐久性を有する。また、この改質金属粉末は、改
質していない金属粉末に比較して、磁気テープ等に使用
された場合に要求される実用特性である耐摩耗性、導電
性、分散性も向上する。Modified Magnetic Metal Powder The modified magnetic metal powder obtained by the above method has a dense graphite coating formed by the catalytic action on the surface of the metal powder, so the decrease in saturation magnetization σS is minimal, and oxidation is sufficient for practical use. It has the durability of prevention. In addition, this modified metal powder also has improved wear resistance, conductivity, and dispersibility, which are practical properties required when used in magnetic tapes, etc., as compared to unmodified metal powder.
また、この改質磁性金属粉末は、高密度磁気記録、電子
写真用トナー、磁性流体等に好適に使用される。Further, this modified magnetic metal powder is suitably used for high-density magnetic recording, electrophotographic toner, magnetic fluid, and the like.
実施例１
鉄を主成分とする酸化物を水素還元して得られる磁性金
属粉末（長軸の平均長さ０．２μｍ、軸比８／］、比表
面積４０ｒｒｆ／ｇ）１００ｇに、Ｃｏ／Ｉ（２＝１．
（モル比）の水性ガスを２００°Ｃ１０、１ｒｄ／ｌｌ
ｒ、 ４０秒間の条件で接触させて反応させた。Example 1 Co/I was added to 100 g of magnetic metal powder (average length of long axis 0.2 μm, axial ratio 8/], specific surface area 40 rrf/g) obtained by hydrogen reduction of an oxide containing iron as the main component. (2=1.
(molar ratio) of water gas at 200°C10, 1rd/ll
r, the reaction was carried out by contacting for 40 seconds.
得られた改質磁性金属粉末を空気中に取り出し、振動試
料型磁化測定器を用い、この粉末の飽和磁化σＳ （初
期値）を測定した。その後、この改質磁性金属粉末を６
０℃、湿度９０％ＲＨの雰囲気中に放置し、３日後、１
週間後、２週間後の飽和磁化σＳをそれぞれ測定し、そ
の値を表１に示した。また、得られた改質粉末は、８．
１重量％の炭素を含有し、この炭素はＸ線回折図よりｄ
ｏｏ２＝３．４への黒鉛構造であった。The obtained modified magnetic metal powder was taken out into the air, and the saturation magnetization σS (initial value) of this powder was measured using a vibrating sample type magnetization measuring device. After that, this modified magnetic metal powder was
Leave it in an atmosphere of 0°C and 90%RH, and after 3 days, 1
The saturation magnetization σS was measured after one week and after two weeks, and the values are shown in Table 1. In addition, the obtained modified powder is 8.
Contains 1% by weight of carbon, and this carbon is d from the X-ray diffraction diagram.
The graphite structure was oo2=3.4.
実施例２
Ｆ ｅ （ＣＯ） ５を気相熱分解して得られる磁性金
属粉末（平均粒子径０． １μｍ、比表面積２１イ／ｇ
）５０ｇにＣＯ／Ｈ２＝Ｉ Ｃモル比）の水性ガスを１
８０℃、０．１Ｔｄ／Ｉ（ｒｓ ２０秒間の条件で接触
させて反応させた。Example 2 Magnetic metal powder obtained by vapor phase pyrolysis of F e (CO) 5 (average particle size 0.1 μm, specific surface area 21 I/g)
) to 50 g of water gas of CO/H2=IC molar ratio)
The reaction was carried out by contacting at 80° C. and 0.1 Td/I (rs) for 20 seconds.
この改質粉末の炭素含有量は６．３重量％であり、この
炭素はＸ線回折図よりｄｏｏ２＝３．４人の黒鉛構造で
あった。The carbon content of this modified powder was 6.3% by weight, and the carbon had a graphite structure of doo2=3.4 according to an X-ray diffraction diagram.
得られた改質磁性金属粉末について、実施例１と同様の
試験を行ない、その結果を第１表に示した。The obtained modified magnetic metal powder was subjected to the same tests as in Example 1, and the results are shown in Table 1.
比較例］
実施例１で使用の水素還元して得られる磁性金属粉末１
００ｇをトルエン中に懸濁させ、８０℃に加温した後、
３００ ｐｌ）ｍの酸素を含む窒素ガスを０． ５ＴＩ
１．／Ｈｒ、 ５時間の条件で吹き込んで、徐酸化処理
を行なった。Comparative Example] Magnetic metal powder 1 obtained by hydrogen reduction used in Example 1
After suspending 00g in toluene and heating to 80°C,
300 pl)m of nitrogen gas containing oxygen was added to the 5TI
1. /Hr for 5 hours to carry out gradual oxidation treatment.
得られた処理磁性金属粉を濾過および乾燥した後、実施
例］と同様の試験を行ない、その結果を第１表に示した
。After filtering and drying the obtained treated magnetic metal powder, tests similar to those in Example] were conducted, and the results are shown in Table 1.
上表から明らかなように、本発明の黒鉛被覆処理方法を
施した各実施例の改質磁性金属粉末の飽和磁化σＳは、
従来の防錆処理方法である徐酸化法で得られた比較例の
処理磁性金属粉末に比べて、飽和磁化σＳの低下が抑制
され、かつ実用的な酸化防止性能が付与されている。As is clear from the above table, the saturation magnetization σS of the modified magnetic metal powder of each example subjected to the graphite coating treatment method of the present invention is:
Compared to the treated magnetic metal powder of the comparative example obtained by the slow oxidation method, which is a conventional rust prevention treatment method, the decrease in saturation magnetization σS is suppressed, and practical oxidation prevention performance is imparted.
Claims (1)
て反応させて、該磁性金属粉末の表面に黒鉛被膜を形成
させることを特徴とする、改質磁性金属粉末の製造法。A method for producing a modified magnetic metal powder, which comprises bringing a hydrocarbon gas or a water gas into contact with a magnetic metal powder to cause a reaction, thereby forming a graphite coating on the surface of the magnetic metal powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63221953A JPH0269904A (en) | 1988-09-05 | 1988-09-05 | Manufacture of modified magnetic metal powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63221953A JPH0269904A (en) | 1988-09-05 | 1988-09-05 | Manufacture of modified magnetic metal powder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0269904A true JPH0269904A (en) | 1990-03-08 |
Family
ID=16774747
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63221953A Pending JPH0269904A (en) | 1988-09-05 | 1988-09-05 | Manufacture of modified magnetic metal powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0269904A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL1008528C2 (en) * | 1998-03-09 | 1999-09-10 | Univ Utrecht | Ferromagnetic particles. |
| JP2007126755A (en) * | 2006-12-28 | 2007-05-24 | Toyo Tanso Kk | Carbon-coated metal particle and method for manufacturing the same |
| JP2010062485A (en) * | 2008-09-08 | 2010-03-18 | Toshiba Corp | Core shell type magnetic material, method of manufacturing core shell type magnetic material, device apparatus, and antenna assembly |
| JP2010062484A (en) * | 2008-09-08 | 2010-03-18 | Toshiba Corp | Core shell type magnetic material, device apparatus, and antenna assembly |
| JP2010087462A (en) * | 2008-09-08 | 2010-04-15 | Toshiba Corp | Core shell-type magnetic material, method of manufacturing the same, device apparatus, and antenna device |
| JP2010212580A (en) * | 2009-03-12 | 2010-09-24 | Kurimoto Ltd | Magnetic viscous fluid |
-
1988
- 1988-09-05 JP JP63221953A patent/JPH0269904A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL1008528C2 (en) * | 1998-03-09 | 1999-09-10 | Univ Utrecht | Ferromagnetic particles. |
| WO1999046782A2 (en) * | 1998-03-09 | 1999-09-16 | Universiteit Utrecht | Ferromagnetic particles |
| WO1999046782A3 (en) * | 1998-03-09 | 1999-10-21 | Univ Utrecht | Ferromagnetic particles |
| JP2007126755A (en) * | 2006-12-28 | 2007-05-24 | Toyo Tanso Kk | Carbon-coated metal particle and method for manufacturing the same |
| JP2010062485A (en) * | 2008-09-08 | 2010-03-18 | Toshiba Corp | Core shell type magnetic material, method of manufacturing core shell type magnetic material, device apparatus, and antenna assembly |
| JP2010062484A (en) * | 2008-09-08 | 2010-03-18 | Toshiba Corp | Core shell type magnetic material, device apparatus, and antenna assembly |
| JP2010087462A (en) * | 2008-09-08 | 2010-04-15 | Toshiba Corp | Core shell-type magnetic material, method of manufacturing the same, device apparatus, and antenna device |
| JP2010212580A (en) * | 2009-03-12 | 2010-09-24 | Kurimoto Ltd | Magnetic viscous fluid |
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