JPH0729764B2 - Iron carbide fine particles, magnetic material and method for producing the fine particles - Google Patents
Iron carbide fine particles, magnetic material and method for producing the fine particlesInfo
- Publication number
- JPH0729764B2 JPH0729764B2 JP62259318A JP25931887A JPH0729764B2 JP H0729764 B2 JPH0729764 B2 JP H0729764B2 JP 62259318 A JP62259318 A JP 62259318A JP 25931887 A JP25931887 A JP 25931887A JP H0729764 B2 JPH0729764 B2 JP H0729764B2
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- fine particles
- compounds
- iron carbide
- carbon
- iron
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Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は炭化鉄微粒子、磁性材料及び該微粒子の製造法
に関する。TECHNICAL FIELD The present invention relates to iron carbide fine particles, a magnetic material and a method for producing the fine particles.
（従来の技術） 針状オキシ水酸化鉄または針状酸化鉄をCO又はこれとH2
との混合物と250〜400℃で接触させることにより炭化鉄
を含有する針状粒子を製造し、これが化学的に安定で高
保磁力を有し磁気記録媒体用の磁性材料として有用であ
ることが知られている（例えば特開昭60-71509号、同60
-108309号、同60-127212号、同60-155522号）。しかし
得られた炭化鉄微粒子は針状粒子であり、長手配向記録
には向いているが、三次元ランダム配向記録や垂直配向
記録には不向きである。(Prior Art) Needle-like iron oxyhydroxide or needle-like iron oxide is replaced with CO or H 2
It is known that the acicular particles containing iron carbide are produced by contacting the mixture with the mixture at 250 to 400 ° C., and that they are chemically stable, have a high coercive force, and are useful as a magnetic material for a magnetic recording medium. (For example, JP-A-60-71509 and 60
-108309, 60-127212, 60-155522). However, the obtained iron carbide fine particles are acicular particles and are suitable for longitudinal alignment recording, but are not suitable for three-dimensional random alignment recording or vertical alignment recording.
これに対して平均軸比の小さい針状でない炭化鉄は、例
えば塗料化に際して充填密度が高くなることが期待さ
れ、その結果磁気記録媒体に応用した場合、飽和磁束密
度の向上が期待される。On the other hand, non-acicular iron carbide having a small average axial ratio is expected to have a high packing density when it is made into a coating material. As a result, when it is applied to a magnetic recording medium, the saturation magnetic flux density is expected to be improved.
（発明が解決しようとする問題点） 本発明の目的はランダム配向及び垂直配向が容易な炭化
鉄微粒子及びその製造法を提供することにある。(Problems to be Solved by the Invention) An object of the present invention is to provide iron carbide fine particles in which random orientation and vertical orientation are easy and a method for producing the same.
また本発明の目的は磁気記録媒体に応用した場合、飽和
磁束密度の向上に貢献する炭化鉄微粒子及びその製造法
を提供することにある。Another object of the present invention is to provide iron carbide fine particles that contribute to an improvement in saturation magnetic flux density when applied to a magnetic recording medium, and a method for producing the same.
（問題点を解決するための手段） 本発明はニツケル化合物、銅化合物及びマンガン化合物
の群から選択された少なくとも１種の金属化合物の被膜
が形成されている平均軸比が１以上３未満のFe5C2を主
成分とする炭化鉄微粒子、該炭化鉄微粒子を主体とする
磁気記録用磁性材料及び該炭化鉄微粒子の製造法に係
る。(Means for Solving Problems) In the present invention, Fe having an average axial ratio of 1 or more and less than 3 in which a coating film of at least one metal compound selected from the group of nickel compounds, copper compounds and manganese compounds is formed. The present invention relates to iron carbide fine particles containing 5 C 2 as a main component, a magnetic material for magnetic recording mainly containing the iron carbide fine particles, and a method for producing the iron carbide fine particles.
本発明の炭化鉄微粒子は（ａ）ニツケル化合物、銅化合
物及びマンガン化合物の群から選択された少なくとも１
種の金属化合物の被膜が形成された平均軸比が１以上３
未満の酸化鉄微粒子に、炭素を含有しない還元剤を接触
させた後または接触させずに、（ｂ）炭素を含有する還
元炭化剤もしくはこれと炭素を含有しない還元剤との混
合物を接触させることにより製造することができる。The iron carbide fine particles of the present invention are (a) at least one selected from the group consisting of nickel compounds, copper compounds and manganese compounds.
The average axial ratio at which a film of a metal compound of one kind is formed is 1 or more 3
(B) contacting a reduced carbonizing agent containing carbon or a mixture thereof with a reducing agent containing no carbon with or without contacting a reducing agent containing no carbon with the iron oxide fine particles of less than Can be manufactured by.
本発明において出発原料の酸化鉄としてはα‐Fe2O
3（ヘマタイト）、γ‐Fe2O3（マグヘマイト）又はFe3O
4（マグネタイト）が好ましいが、鉄（II）塩水溶液を
アルカリで中和しつつ空気を吹き込み合成したマグネタ
イトもしくはこれを更に加熱酸化して得た酸化鉄（II
I）微粒子が特に好ましい。In the present invention, α-Fe 2 O is used as the starting iron oxide.
3 (hematite), γ-Fe 2 O 3 (maghemite) or Fe 3 O
4 (magnetite) is preferred, but magnetite synthesized by blowing air into the iron (II) salt aqueous solution while neutralizing the iron (II) salt aqueous solution or iron oxide (II) obtained by further heating and oxidizing it (II
I) Fine particles are particularly preferred.
本発明において原料の酸化鉄は平均軸比が1.0以上3.0未
満のものであり、平均粒径（長軸）は0.05μｍを越え１
μｍ以下、特に0.1μｍを越え0.5μｍ以下が好ましい。
後にも述べるように、製造される粒子は、平均軸比及び
平均粒径が、これらの原料のそれらと比較して若干小さ
くなるが殆ど変らず、本発明の粒子一般について通常こ
のようなものが好適であるからである。In the present invention, the raw material iron oxide has an average axial ratio of 1.0 or more and less than 3.0 and an average particle size (major axis) of more than 0.05 μm.
It is preferably not more than μm, particularly more than 0.1 μm and not more than 0.5 μm.
As will be described later, the particles produced have an average axial ratio and an average particle diameter which are slightly smaller than those of these raw materials but hardly change. This is because it is suitable.
また、本発明で使用する酸化鉄は、主成分が酸化鉄であ
る限り、少量の銅、マグネシウム、マンガン、ニツケ
ル、コバルトの酸化物、炭酸塩；硅素の酸化物；カリウ
ム塩、ナトリウム塩等を添加して成るものであつてもよ
い。The iron oxide used in the present invention contains a small amount of copper, magnesium, manganese, nickel, cobalt oxides, carbonates, silicon oxides, potassium salts, sodium salts, etc. as long as the main component is iron oxide. It may be added.
上記酸化鉄は、特開昭60-108309号にあるように、その
表面のpHが５以上の場合は、より高保磁力を有する粒子
が得られ、好ましい。pHが５未満の場合は、アルカリ
（例えば水酸化ナトリウム、水酸化カリウム、水酸化ア
ンモニウム）水溶液と接触させてpHを５以上とするのが
よい。アルカリ処理は、例えば被処理物を水酸化ナトリ
ウム、水酸化カリウム、水酸化アンモニウムのようなア
ルカリの水溶液（例えば、pH8以上、好ましくは10以上
の水溶液）と接触させて、必要ならば30分〜１時間撹拌
して、別、乾燥することにより行うことができる。表
面pHは、試料5gを蒸留水100ccで１時間煮沸し、室温ま
で冷却後、１時間放置し、その上澄液のpHをpHメーター
で測定した値と定義される。As described in JP-A-60-108309, the above iron oxide is preferable when the pH of the surface is 5 or more, because particles having a higher coercive force can be obtained. When the pH is less than 5, it is preferable to bring the pH to 5 or more by contacting it with an aqueous solution of alkali (eg, sodium hydroxide, potassium hydroxide, ammonium hydroxide). The alkaline treatment is carried out, for example, by contacting the treatment object with an aqueous solution of an alkali such as sodium hydroxide, potassium hydroxide or ammonium hydroxide (for example, an aqueous solution having a pH of 8 or more, preferably 10 or more), and if necessary, for 30 minutes to It can be carried out by stirring for 1 hour, separating and drying. The surface pH is defined as a value obtained by boiling 5 g of a sample in 100 cc of distilled water for 1 hour, cooling it to room temperature and then leaving it for 1 hour, and measuring the pH of the supernatant with a pH meter.
なお、原料は特開昭60-141611号に記載されるように、
珪素化合物、ホウ素化合物、アルミニウム化合物、脂肪
族カルボン酸もしくはその塩、リン化合物又はチタン化
合物などの焼結防止剤で被覆して用いることもできる。Incidentally, the raw material, as described in JP-A-60-141611,
It can also be used by coating with a sintering inhibitor such as a silicon compound, a boron compound, an aluminum compound, an aliphatic carboxylic acid or its salt, a phosphorus compound or a titanium compound.
本発明では上記酸化鉄の表面にニツケル化合物、銅化合
物及びマンガン化合物の群から選択された少なくとも１
種からなる被膜を形成せしめて使用する。ニツケル化合
物としては例えば酢酸ニツケル、シユウ化ニツケル、塩
化ニツケル、硝酸ニツケル、硫酸ニツケル等、銅化合物
としては例えば酢酸銅、シユウ化銅（II）、塩化銅（I
I）、硝酸銅、硝酸銅（II）等、マンガン化合物として
は例えば硫酸マンガン、硝酸マンガン、塩化マンガン、
シュウ化マンガン等を挙げることができる。これら金属
化合物の酸化鉄表面への被着は、例えば酸化鉄懸濁液に
上記金属化合物の水溶液（例えば濃度、約５〜20wt％）
の添加後、中和反応を行い、過、乾燥することにより
行われる。これら金属化合物の添加量は酸化鉄に対して
約0.01〜5wt％とするのが好ましい。次に上記で得られ
た酸化鉄微粒子を接触反応に供する。In the present invention, at least 1 selected from the group of nickel compounds, copper compounds and manganese compounds on the surface of the iron oxide.
It is used by forming a coating consisting of seeds. Examples of the nickel compound are nickel acetate, nickel nitrate, nickel chloride, nickel nitrate, nickel sulfate, and the like, and the copper compound is, for example, copper acetate, copper (II) chloride, copper chloride (I
I), copper nitrate, copper (II) nitrate and the like, examples of manganese compounds include manganese sulfate, manganese nitrate, manganese chloride,
Examples include manganese oxalate and the like. The deposition of these metal compounds on the surface of iron oxide is carried out, for example, by adding an aqueous solution of the above metal compound to an iron oxide suspension (for example, concentration, about 5 to 20 wt%).
Is added, a neutralization reaction is performed, and excess and drying are performed. The addition amount of these metal compounds is preferably about 0.01 to 5 wt% with respect to iron oxide. Next, the iron oxide fine particles obtained above are subjected to a catalytic reaction.
本発明において炭素を含有しない還元剤の代表例として
はH2、NH2NH2等を挙げることができる。In the present invention, typical examples of the reducing agent containing no carbon include H 2 and NH 2 NH 2 .
また炭素を含有する還元炭化剤としては下記化合物の少
なくとも１種以上を使用できる。As the carbonizing agent containing carbon, at least one of the following compounds can be used.
CO 脂肪族、鎖状もしくは環状の、飽和もしくは不飽和
炭化水素、例えばメタン、プロパン、ブタン、シクロヘ
キサン、メチルシクロヘキサン、アセチレン、エチレ
ン、プロピレン、ブタジエン、イソプレン、タウンガス
など。CO 2 aliphatic, linear or cyclic, saturated or unsaturated hydrocarbons such as methane, propane, butane, cyclohexane, methylcyclohexane, acetylene, ethylene, propylene, butadiene, isoprene, town gas and the like.
芳香族炭化水素、例えばベンゼン、トルエン、キシ
レン、沸点150℃以下のこれらのアルキル、アルケニル
誘導体。Aromatic hydrocarbons such as benzene, toluene, xylene, and their alkyl and alkenyl derivatives having a boiling point of 150 ° C or lower.
脂肪族アルコール、例えばメタノール、エタノー
ル、プロパノール、シクロヘキサノール。Aliphatic alcohols such as methanol, ethanol, propanol, cyclohexanol.
エステル、例えばギ酸メチル、酢酸エチル等の沸点
150℃以下のエステル。Boiling point of esters such as methyl formate and ethyl acetate
Ester below 150 ℃.
エーテル、例えば低級アルキルエーテル、ビニルエ
ーテル等の沸点150℃以下のエーテル。Ethers such as lower alkyl ethers and vinyl ethers having a boiling point of 150 ° C or lower.
アルデヒド、例えばホルムアルデヒド、アセトアル
デヒド等の沸点150℃以下のアルデヒド。Aldehydes such as formaldehyde and acetaldehyde having a boiling point of 150 ° C or lower.
ケトン、例えばアセトン、メチルエチルケトン、メ
チルイソブチルケトン等の沸点150℃以下のケトン。Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, etc., having a boiling point of 150 ° C. or less.
特に好ましい炭素を含有する還元炭化剤はCO、CH3OH、H
COOCH3、炭素数１〜５の飽和または不飽和の脂肪族炭化
水素である。Particularly preferred carbon-containing reducing carbonizing agents are CO, CH 3 OH, H
COOCH 3 is a saturated or unsaturated aliphatic hydrocarbon having 1 to 5 carbon atoms.
本発明の（ａ）工程において炭素を含有しない還元剤は
希釈してあるいは希釈せずに使用することができ、希釈
剤としては、例えばN2、CO2、アルゴン、ヘリウム等を
挙げることができる。また希釈率は任意に選択でき、例
えば約1.1〜10倍（容量比）に希釈するのが好ましい。
接触温度、接触時間、流速等の接触条件は、例えば酸化
鉄の製造履歴、平均軸比、平均粒径、比表面積等に応じ
変動するため、適宜選択するのがよい。好ましい接触温
度は、約200〜700℃、より好ましくは約300〜400℃、好
ましい接触時間は約0.5〜６時間である。好ましい流速
は、原料の鉄化合物1g当り約１〜1000ml S.T.P/分であ
る。なお、接触圧力は、希釈剤をも含めて、１〜２気圧
が常用されるが、特に制限はない。In the step (a) of the present invention, the carbon-free reducing agent can be used with or without dilution, and examples of the diluent include N 2 , CO 2 , argon, helium and the like. . The dilution ratio can be arbitrarily selected, and for example, it is preferable to dilute about 1.1 to 10 times (volume ratio).
The contact conditions such as contact temperature, contact time, and flow rate vary depending on, for example, the production history of iron oxide, the average axial ratio, the average particle size, the specific surface area, and the like, and thus may be appropriately selected. The preferred contact temperature is about 200-700 ° C, more preferably about 300-400 ° C, and the preferred contact time is about 0.5-6 hours. A preferred flow rate is about 1-1000 ml STP / min / g of raw iron compound. The contact pressure is usually 1 to 2 atm including the diluent, but is not particularly limited.
本発明の（ｂ）工程においても炭素を含有する還元炭化
剤もしくはこれと炭素を含有しない還元剤との混合物を
希釈してあるいは希釈せずに使用できる。混合物を用い
る場合、その混合比は適宜に選択することができるが、
通常は炭素を含有する還元炭化剤と炭素を含有しない還
元剤の容量比が1/0.05〜1/5とするのが好ましい。接触
条件も同様に適宜選択することができるが、好ましい接
触温度は約250〜400℃、より好ましくは約300〜400℃、
好ましい接触時間は、（ａ）工程を行つた場合は約0.5
〜６時間、（ａ）工程のない場合は約１〜12時間であ
る。好ましい流速は、原料の鉄化合物1g当り約１〜1000
ml S.T.P/分である。なお、接触圧力は、希釈剤をも含
めて、１〜２気圧が常用されるが、特に制限はない。Also in the step (b) of the present invention, the reducing carbonizing agent containing carbon or a mixture of the reducing carbonizing agent and the reducing agent not containing carbon can be used with or without dilution. When using a mixture, the mixing ratio can be appropriately selected,
Usually, the volume ratio of the reducing carbonizing agent containing carbon and the reducing agent containing no carbon is preferably 1 / 0.05 to 1/5. The contact conditions can be appropriately selected as well, but the preferred contact temperature is about 250 to 400 ° C, more preferably about 300 to 400 ° C.
The preferred contact time is about 0.5 when step (a) is performed.
~ 6 hours, about 1-12 hours without step (a). A preferable flow rate is about 1 to 1000 per 1 g of the raw iron compound.
ml STP / min. The contact pressure is usually 1 to 2 atm including the diluent, but is not particularly limited.
本発明において得られる粒子は、電子顕微鏡で観察する
と、平均的に一様な粒子であり、原料の酸化鉄の粒子と
同形状で、これらの形骸粒子であり、これが一次粒子と
なつて存在している。また、得られる粒子は、元素分析
により炭素を含有し、更にＸ線回折パターンにより、炭
化鉄を含有することが明らかである。Ｘ線回折パターン
は、面間隔が2.28、2.20、2.08、2.05及び1.92Åを示
す。かかるパターンは、Fe5C2に相当し、本発明の炭化
鉄は通常は主としてFe5C2からなるが、Fe2C、Fe20C9(Fe
2.2C)、Fe3C等が共存することがある。従つて本発明の
粒子に含有される炭化鉄は、FexC（２≦ｘ＜３）と表示
するのが適切である。The particles obtained in the present invention, when observed by an electron microscope, are uniformly particles having the same shape as the particles of the raw material iron oxide, and these skeleton particles are present as primary particles. ing. Further, it is clear that the obtained particles contain carbon by elemental analysis and further contain iron carbide by X-ray diffraction pattern. The X-ray diffraction pattern shows interplanar spacings of 2.28, 2.20, 2.08, 2.05 and 1.92Å. Such a pattern corresponds to Fe 5 C 2 , and the iron carbide of the present invention usually consists mainly of Fe 5 C 2 , but Fe 2 C, Fe 20 C 9 (Fe
2.2 C), Fe 3 C, etc. may coexist. Therefore, the iron carbide contained in the particles of the present invention is appropriately represented by FexC (2 ≦ x <3).
本発明の炭化鉄微粒子は、前述の特徴等から明らかなと
おり、磁気記録用磁性材料として用いることができる
が、これに限られるものではなく、低級脂肪族炭化水素
のCOとH2とからの合成のための触媒等として用いること
もできる。The iron carbide fine particles of the present invention can be used as a magnetic material for magnetic recording, as is apparent from the above-mentioned characteristics, but the present invention is not limited to this, and the lower aliphatic hydrocarbons CO and H 2 can be used. It can also be used as a catalyst or the like for synthesis.
（発明の効果） 本発明の方法によれば球状もしくは球状に近い炭化鉄微
粒子が得られ、これは形状で異方性がないため、等方
（三次元ランダム）、垂直配向が可能となり、より高密
度記録媒体を作ることができる。又導電率が大きいこ
と、磁化量が大きいことから、バリウムフエライト等の
磁化量の小さい磁性粉の添加剤としても有効である。(Effect of the Invention) According to the method of the present invention, spherical or nearly spherical iron carbide fine particles are obtained, and since this has no anisotropy in shape, isotropic (three-dimensional random) and vertical orientation are possible, and more A high-density recording medium can be made. Further, since it has a large conductivity and a large amount of magnetization, it is also effective as an additive for magnetic powder having a small amount of magnetization such as barium ferrite.
（実施例） 以下に実施例を挙げて詳しく説明する。(Examples) Hereinafter, examples will be described in detail.
実施例において、各特性はそれぞれ次の方法によつて求
めた。In the examples, each characteristic was obtained by the following method.
（１）磁気特性 磁気特性即ち保磁力Hc（Oe）、飽和磁化量σｓ（e.m.
u.）及び角型比Sqはホール素子を用いたガウスメーター
により、試料充填率0.2、測定磁場10kOeで測定して求め
た。(1) Magnetic characteristics Magnetic characteristics, that is, coercive force Hc (Oe), saturation magnetization σs (em
u.) and the squareness ratio Sq were obtained by measuring with a Gauss meter using a Hall element at a sample filling rate of 0.2 and a measuring magnetic field of 10 kOe.
実施例１ 平均粒径0.3μｍ、平均軸比１の球状マグネタイト粒子
の懸濁液に塩化ニツケルの水溶液を添加し、水酸化ナト
リウムで中和反応を行い、過後、80℃で乾燥して表面
に水酸化ニツケルの被着したマグネタイト粒子を得た。
この粒子2gを磁性ボートに入れて管状炉に挿入し、窒素
を流して置換した後に400℃に昇温し、その温度でCOを
毎分1000mlの流速で５時間接触させ、その後室温まで放
冷して黒色の粉末を得た。生成物のＸ線回析パターンは
ASTMのX-Ray Powder Data File 20-509 Fe5C2 Iron Car
bideと一致した。磁気特性は第１表に示す。Example 1 An aqueous solution of nickel chloride was added to a suspension of spherical magnetite particles having an average particle size of 0.3 μm and an average axial ratio of 1, and a neutralization reaction was carried out with sodium hydroxide. After passing, the surface was dried at 80 ° C. Magnetite particles coated with nickel hydroxide were obtained.
2 g of these particles are put in a magnetic boat, inserted into a tubular furnace, replaced by flowing nitrogen, heated to 400 ° C., CO is contacted at that temperature at a flow rate of 1000 ml / min for 5 hours, and then allowed to cool to room temperature. A black powder was obtained. The X-ray diffraction pattern of the product is
ASTM X-Ray Powder Data File 20-509 Fe 5 C 2 Iron Car
Matched with bide. The magnetic properties are shown in Table 1.
実施例２〜３ 塩化ニツケル水溶液の代りに、硫酸銅水溶液又は硫酸マ
ンガン水溶液を用いた以外は実施例１と同様にして黒色
の粉末を得た。結果を第１表に示す。Examples 2 to 3 Black powders were obtained in the same manner as in Example 1 except that a copper sulfate aqueous solution or a manganese sulfate aqueous solution was used instead of the nickel chloride aqueous solution. The results are shown in Table 1.
実施例４ 塩化アルミニウム水溶液及び塩化ニツケル水溶液の混合
液（Al/Ni＝0.3/1.0重量比）を用いた以外は実施例１と
同様にして黒色の粉末を得た。結果を第１表に示す。Example 4 A black powder was obtained in the same manner as in Example 1 except that a mixed solution (Al / Ni = 0.3 / 1.0 weight ratio) of an aluminum chloride aqueous solution and a nickel chloride aqueous solution was used. The results are shown in Table 1.
参考例１ 塩化ニツケル水溶液の代りに、塩化アルミニウム水溶液
を用いた以外は実施例１と同様にして黒色の粉末を得
た。結果を第１表に示す。Reference Example 1 A black powder was obtained in the same manner as in Example 1 except that an aqueous solution of aluminum chloride was used instead of the aqueous solution of nickel chloride. The results are shown in Table 1.
比較例１ 金属を被着しない以外は実施例１と同様にして黒色の粉
末を得た。結果を第１表に示す。Comparative Example 1 A black powder was obtained in the same manner as in Example 1 except that no metal was adhered. The results are shown in Table 1.
比較例２ 平均粒径0.3μｍ、平均軸比１の球状マグネタイト粒子2
gを磁性ボートに入れて管状炉に挿入し、窒素を流して
置換した後に400℃に昇温し、その温度でH2を毎分1000m
lの流速で１時間接触させた。引き続き、その温度でCO
を毎分1000mlの流速で５時間接触させ、その後室温まで
放冷して黒色の粉末を得た。結果を第１表に示す。Comparative Example 2 Spherical magnetite particles 2 having an average particle size of 0.3 μm and an average axial ratio of 1
Put g in a magnetic boat, insert into a tubular furnace, replace with nitrogen by flowing it, and then raise the temperature to 400 ° C., and at that temperature H 2 1000 m / min
Contact was performed for 1 hour at a flow rate of l. Then, at that temperature, CO
Were contacted at a flow rate of 1000 ml / min for 5 hours, and then allowed to cool to room temperature to obtain a black powder. The results are shown in Table 1.
実施例１で得られた粒子は第１図にみられる様に球状粒
子であり、第１表にみられる様に球状でありながら角型
比も大きく、かつ等方、垂直記録用磁性粉末としては磁
化量が大きい。 The particles obtained in Example 1 are spherical particles as shown in FIG. 1, and are spherical as shown in Table 1 and have a large squareness ratio, and are magnetic powders for isotropic and perpendicular recording. Has a large amount of magnetization.
第１図は実施例１で得られた粒子の粒子構造を示す電子
顕微鏡写真（倍率20,000倍）である。FIG. 1 is an electron micrograph (magnification: 20,000 times) showing the particle structure of the particles obtained in Example 1.
フロントページの続き (56)参考文献 特開 昭61−19502（ＪＰ，Ａ) 特開 昭61−234506（ＪＰ，Ａ) 特開 昭61−111921（ＪＰ，Ａ) 特開 昭61−141611（ＪＰ，Ａ) 特開 昭63−17212（ＪＰ，Ａ)Continuation of front page (56) Reference JP 61-19502 (JP, A) JP 61-234506 (JP, A) JP 61-111921 (JP, A) JP 61-141611 (JP , A) Japanese Patent Laid-Open No. 63-17212 (JP, A)
Claims (3)
合物の群から選択された少なくとも１種の金属化合物の
被膜が形成されている平均軸比が１以上３未満のFe5C2
を主成分とする炭化鉄微粒子。1. A Fe 5 C 2 having an average axial ratio of 1 or more and less than 3 on which a film of at least one metal compound selected from the group of nickel compounds, copper compounds and manganese compounds is formed.
Iron carbide fine particles containing as a main component.
合物の群から選択された少なくとも１種の金属化合物の
被膜が形成されている平均軸比が１以上３未満のFe5C2
を主成分とする炭化鉄微粒子を主体とする磁気記録用磁
性材料。 2. Fe 5 C 2 having an average axial ratio of 1 or more and less than 3 in which a film of at least one metal compound selected from the group of nickel compounds, copper compounds and manganese compounds is formed.
A magnetic material for magnetic recording mainly containing iron carbide fine particles.
ら選択された少なくとも１種の金属化合物の被膜が形成
された平均軸比が１以上３未満の酸化鉄微粒子に、炭素
を含有しない還元剤を接触させた後または接触させず
に、 （ｂ）炭素を含有する還元炭化剤もしくはこれと炭素を
含有しない還元剤との混合物を接触させることを特徴と
する銅化合物及びマンガン化合物の群から選択された少
なくとも１種の金属化合物の被膜が形成されている平均
軸比が１以上３未満のFe5C2を主成分とする炭化鉄微粒
子の製造法。3. (a) Carbon-free reduction of iron oxide fine particles having an average axial ratio of 1 or more and less than 3 on which a film of at least one metal compound selected from the group of copper compounds and manganese compounds is formed. From the group of copper compounds and manganese compounds, characterized in that (b) a reducing carbonizing agent containing carbon or a mixture of this and a reducing agent containing no carbon is contacted after or without contacting the agent. A method for producing iron carbide fine particles containing Fe 5 C 2 as a main component, having an average axial ratio of 1 or more and less than 3 on which a coating film of at least one selected metal compound is formed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62259318A JPH0729764B2 (en) | 1987-10-14 | 1987-10-14 | Iron carbide fine particles, magnetic material and method for producing the fine particles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62259318A JPH0729764B2 (en) | 1987-10-14 | 1987-10-14 | Iron carbide fine particles, magnetic material and method for producing the fine particles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01103911A JPH01103911A (en) | 1989-04-21 |
| JPH0729764B2 true JPH0729764B2 (en) | 1995-04-05 |
Family
ID=17332414
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62259318A Expired - Lifetime JPH0729764B2 (en) | 1987-10-14 | 1987-10-14 | Iron carbide fine particles, magnetic material and method for producing the fine particles |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0729764B2 (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60141611A (en) * | 1983-12-28 | 1985-07-26 | Daikin Ind Ltd | Acicular particle of iron carbide and its preparation |
| JPS61111921A (en) * | 1984-11-01 | 1986-05-30 | Daikin Ind Ltd | Production of acicular particle containing iron carbide |
| JPS61196502A (en) * | 1985-02-27 | 1986-08-30 | Mitsui Toatsu Chem Inc | Magnetic material and manufacture thereof |
| JPS61234506A (en) * | 1985-04-11 | 1986-10-18 | Mitsui Toatsu Chem Inc | Magnetic material and manufacture thereof |
| JPH0635326B2 (en) * | 1986-07-04 | 1994-05-11 | ダイキン工業株式会社 | Method for producing particles containing iron carbide |
-
1987
- 1987-10-14 JP JP62259318A patent/JPH0729764B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01103911A (en) | 1989-04-21 |
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