JPH0412008A - Production of magnetic powder - Google Patents
Production of magnetic powderInfo
- Publication number
- JPH0412008A JPH0412008A JP2112703A JP11270390A JPH0412008A JP H0412008 A JPH0412008 A JP H0412008A JP 2112703 A JP2112703 A JP 2112703A JP 11270390 A JP11270390 A JP 11270390A JP H0412008 A JPH0412008 A JP H0412008A
- Authority
- JP
- Japan
- Prior art keywords
- transition metal
- compound
- reaction
- mixed gas
- magnetic field
- 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
- 239000006247 magnetic powder Substances 0.000 title claims description 17
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 229910052723 transition metal Inorganic materials 0.000 claims abstract description 26
- -1 transition metal carbonyl compound Chemical class 0.000 claims abstract description 22
- 150000003623 transition metal compounds Chemical class 0.000 claims abstract description 13
- 150000001875 compounds Chemical class 0.000 claims abstract description 11
- 150000003624 transition metals Chemical class 0.000 claims abstract description 8
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 28
- 229910021529 ammonia Inorganic materials 0.000 claims description 14
- 238000010574 gas phase reaction Methods 0.000 claims description 5
- 238000006243 chemical reaction Methods 0.000 abstract description 22
- 239000000843 powder Substances 0.000 abstract description 13
- 230000005415 magnetization Effects 0.000 abstract description 9
- 239000012808 vapor phase Substances 0.000 abstract 2
- 229910017147 Fe(CO)5 Inorganic materials 0.000 abstract 1
- 229920006395 saturated elastomer Polymers 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 19
- 229910052751 metal Inorganic materials 0.000 description 16
- 239000002184 metal Substances 0.000 description 16
- 150000004767 nitrides Chemical class 0.000 description 11
- 239000007789 gas Substances 0.000 description 8
- 238000000034 method Methods 0.000 description 7
- 239000000203 mixture Substances 0.000 description 7
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 6
- 229910052742 iron Inorganic materials 0.000 description 6
- 238000005755 formation reaction Methods 0.000 description 5
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 229910001337 iron nitride Inorganic materials 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 238000002083 X-ray spectrum Methods 0.000 description 2
- 238000007259 addition reaction Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000000197 pyrolysis Methods 0.000 description 2
- 239000012495 reaction gas Substances 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000011203 carbon fibre reinforced carbon Substances 0.000 description 1
- 150000001728 carbonyl compounds Chemical class 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 229910006297 γ-Fe2O3 Inorganic materials 0.000 description 1
Abstract
Description
【発明の詳細な説明】
〔発明の背景〕
（産業上の利用分野）
本発明は磁気記録用途に好適な磁性粉末の製造法に関す
る。更に詳しくは、高密度磁気記録媒体等に適する優れ
た磁気特性と耐久性を有する窒化遷移金属磁性粉末の製
造法に関する。DETAILED DESCRIPTION OF THE INVENTION [Background of the Invention] (Field of Industrial Application) The present invention relates to a method for producing magnetic powder suitable for magnetic recording applications. More specifically, the present invention relates to a method for producing transition metal nitride magnetic powder having excellent magnetic properties and durability suitable for high-density magnetic recording media and the like.
（従来の技術）
近年、磁気記録の高密度化の要求に伴い、記録媒体用途
に従来用いられていたγ−Ｆｅ２Ｏ３、Ｃｏ被被着−Ｆ
ｅ２０３などの酸化鉄に代わり、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粉が実用化
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 for recording media,
In place of iron oxide such as e203, magnetic powders of iron or iron-based alloys having high coercive force and high residual magnetization have been put into practical use.
しかし、これら鉄系磁性粉は、空気中の酸化を受は易い
不安定な性質を有し、これを安定化させる為に表面に酸
化被膜を形成させることから、残留磁化が金属本来のそ
の値に比較するとそれほど大きくないという欠点がある
。However, these iron-based magnetic powders have unstable properties that are easily susceptible to oxidation in the air, and in order to stabilize this, an oxide film is formed on the surface, so the residual magnetization is lower than the original value of the metal. The disadvantage is that it is not very large compared to .
一方、窒化遷移金属磁性材料、とりわけ窒化鉄磁性材料
は、金属並みの高残留磁化を有し、しかも金属の欠点で
ある酸化劣化に対しても酸化を受は難く耐久性を有する
ことから、磁気記録材料としての開発が行なわれている
（田崎明他 固体物理：１１．７２１．１９８４）。On the other hand, transition metal nitride magnetic materials, especially iron nitride magnetic materials, have high residual magnetization comparable to that of metals, and are resistant to oxidation deterioration, which is a drawback of metals, and are therefore durable. It is being developed as a recording material (Akira Tasaki et al. Solid State Physics: 11.721.1984).
この磁気記録用窒化鉄磁性粉末の製造法としては、一般
に針状の酸化鉄または鉄をアンモニアと水素の混合気体
中において３５０〜４５０℃て少なくとも３時間以上反
応させることにより形成する方法が知られている。しか
しながら、この方法で得られる窒化鉄磁性粉末は、酸化
鉄または鉄が還元過程における焼結防止のための不純物
を含んでいなければならないこと並びに該粉末か多孔性
の構造であるために結晶および組成が不均一となり優れ
た磁気特性、特に高保磁力か得られないという欠点かあ
った。A generally known method for manufacturing iron nitride magnetic powder for magnetic recording is to form it by reacting acicular iron oxide or iron in a mixed gas of ammonia and hydrogen at 350 to 450°C for at least 3 hours. ing. However, the iron nitride magnetic powder obtained by this method must contain impurities to prevent iron oxide or iron from sintering during the reduction process, and because the powder has a porous structure, crystals and The disadvantage was that the composition was non-uniform and excellent magnetic properties, especially high coercive force, could not be obtained.
本発明の目的は、従来技術の欠点を解消し、不純物の混
入がなく、高保磁力、高飽和磁化を有する、磁気記録材
料に好適な窒化遷移金属磁性粉末の製造法を提供するこ
とである。An object of the present invention is to provide a method for producing transition metal nitride magnetic powder suitable for magnetic recording materials, which eliminates the drawbacks of the prior art, is free of impurities, has high coercive force, and high saturation magnetization.
本発明者等は、上記従来技術の欠点を解消すべく鋭意検
討の結果、出発金属材料として特定の有機遷移金属化合
物を使用し、これとアンモニアとを特定の磁場を印加し
た気相反応系において反応させることにより、生成物の
組成並びに結晶構造が均一で、かつ高保磁力、高飽和磁
化を有する窒化遷移金属磁性粉末が得られることを見い
出し、本発明を完成した。As a result of intensive studies to eliminate the drawbacks of the above-mentioned prior art, the present inventors used a specific organic transition metal compound as a starting metal material, and combined this with ammonia in a gas phase reaction system by applying a specific magnetic field. The present invention was completed based on the discovery that a transition metal nitride magnetic powder having a uniform product composition and crystal structure, high coercive force, and high saturation magnetization can be obtained by the reaction.
即ち、本発明による磁性粉末の製造法は、遷移金属カル
ボニル化合物および遷移金属のπ−コンプレックス化合
物から選択される有機遷移金属化合物とアンモニアとを
１００ガウス以上の磁場を印加した気相反応系において
反応させることにより窒化遷移金属磁性粉末を生成させ
ることを特徴とするものである。That is, the method for producing magnetic powder according to the present invention involves reacting an organic transition metal compound selected from transition metal carbonyl compounds and transition metal π-complex compounds with ammonia in a gas phase reaction system in which a magnetic field of 100 Gauss or more is applied. The present invention is characterized in that transition metal nitride magnetic powder is produced by this process.
有機遷移金属化合物
本発明においては、出発金属材料として、遷移金属カル
ボニル化合物および遷移金属のπ−コンプレックス化合
物から選択される有機遷移金属化合物（以下、簡単のた
め単に「有機遷移金属化合物」と称する）が使用される
。遷移金属カルボニル化合物としては、Ｆｅ、Ｎ １Ｓ
Ｃｏ、Ｗ、Ｍ。Organic transition metal compound In the present invention, an organic transition metal compound selected from transition metal carbonyl compounds and transition metal π-complex compounds (hereinafter simply referred to as "organic transition metal compound" for simplicity) is used as a starting metal material. is used. As transition metal carbonyl compounds, Fe, N 1S
Co, W, M.
等のカルボニル化合物、例えば、Ｆｅ （Ｃｏ） ５、
及びこれらの混合物がある。また、遷移金属のπ−コン
プレックス化合物とは、炭素間２重結合または３重結合
と金属が結合したものであり、具体的には（π−Ｃ５Ｈ
５） ２Ｆｅ。carbonyl compounds such as Fe(Co)5,
and mixtures thereof. In addition, a π-complex compound of a transition metal is a compound in which a carbon-carbon double bond or triple bond is bonded to a metal, specifically (π-C5H
5) 2Fe.
（π−ＣＨ）（π−Ｃ６Ｈ７）Ｆｅ。(π-CH)(π-C6H7)Fe.
（π−Ｃ５Ｈ５）２ＣＯ５等のメタセロン化合物を挙げ
ることができる。これらのうち、最も好ましいものはＦ
ｅ（Ｃｏ）５である。Examples include metatheron compounds such as (π-C5H5)2CO5. Among these, the most preferable one is F
e(Co)5.
窒化遷移金属粉末の製造
本発明による窒化遷移金属粉末の製造は、上記有機遷移
金属化合物とアンモニアとを１００ガウス以上の磁場を
印加した気相中で反応させることによって行うものであ
って、その具体的な製造法は、例えば下記に示す通りで
ある。Production of transition metal nitride powder Production of transition metal nitride powder according to the present invention is carried out by reacting the organic transition metal compound and ammonia in a gas phase with a magnetic field of 100 Gauss or more applied. A typical manufacturing method is as shown below, for example.
好ましい一つの方法は、窒化金属形成反応を２段階で実
施することからなるものである。この好ましい方法によ
れば、窒化金属の結晶及び組成か均一で形状か一定に調
節された粉末を得ることかできる。One preferred method consists of carrying out the metal nitride formation reaction in two stages. According to this preferred method, it is possible to obtain a metal nitride powder whose crystal and composition are uniform and whose shape is controlled to be constant.
すなわち、第一段階は、第一の気相反応ゾーンで有機遷
移金属化合物とアンモニアを反応させて有機遷移金属の
アンモニア付加化合物またはアミノ化合物を形成させる
ものであって、
例えばＦ ｅ （ＣＯ） ５を使用する場合はＦｅ（Ｃ
Ｏ）４ＮＨ３、
［Ｆ ｅ （ＣＯ） ３ Ｎ Ｈ−）っ等およびこれら
の混合物が形成される。このような化合物の形成により
、第二段階における窒化金属の形成反応において、有機
遷移金属化合物の熱分解による金属粉の形成を抑制させ
て、窒化金属の形成の選択率を向上させることができる
。That is, the first step is to react the organic transition metal compound and ammonia in the first gas phase reaction zone to form an ammonia addition compound or an amino compound of the organic transition metal, for example, F e (CO) 5 When using Fe(C
O)4NH3, [Fe(CO)3NH-), etc., and mixtures thereof are formed. By forming such a compound, the formation of metal powder due to thermal decomposition of the organic transition metal compound can be suppressed in the metal nitride formation reaction in the second step, and the selectivity for metal nitride formation can be improved.
この第一段階の反応は、例えば、有機遷移金属化合物を
、アンモニアまたはアンモニアと水素の混合気体で１〜
６０体積％（好ましくは５〜５０体積９６）の割合で希
釈した混合気体とし、反応温度１０〜２００℃、好まし
くは５０〜１８０℃、滞留時間３０秒〜１時間、好まし
くは１〜２０分の条件下にて行うことができる。この段
階の反応においては、磁場の印加は必ずしも必要ではな
い。In this first stage reaction, for example, an organic transition metal compound is mixed with ammonia or a mixed gas of ammonia and hydrogen for 1 to 30 minutes.
A mixed gas diluted at a ratio of 60% by volume (preferably 5 to 50% by volume96), a reaction temperature of 10 to 200°C, preferably 50 to 180°C, and a residence time of 30 seconds to 1 hour, preferably 1 to 20 minutes. This can be done under certain conditions. At this stage of the reaction, application of a magnetic field is not necessarily required.
第二段階は、第二の気相反応ゾーンで上記第一反応ゾー
ンを経た反応気体を気相熱分解反応に付すことによって
窒化遷移金属粉末を形成させるためのものである。具体
的には、例えば、上記の反応気体を更にアンモニアまた
はアンモニアと水素の混合気体で希釈して３体積％以下
、好ましくは１．５体積％以下（投入有機遷移金属化合
物を基準として換算）とし、この混合気体を１００ガウ
ス以上、好ましくは３００ガウス以上、特に好ましくは
５００〜１５００ガウスの磁場を印加した反応系内に２
５０〜７００℃、５分以下（好ましくは３００〜５００
℃、２分以下）滞留させて気相熱分解反応を行なうこと
により窒化金属粉末を形成させる。The second stage is for forming transition metal nitride powder by subjecting the reaction gas that has passed through the first reaction zone to a gas phase pyrolysis reaction in a second gas phase reaction zone. Specifically, for example, the above reaction gas is further diluted with ammonia or a mixed gas of ammonia and hydrogen to make it 3% by volume or less, preferably 1.5% by volume or less (calculated based on the input organic transition metal compound). , this gas mixture is placed in a reaction system to which a magnetic field of 100 Gauss or more, preferably 300 Gauss or more, particularly preferably 500 to 1500 Gauss is applied.
50-700℃, 5 minutes or less (preferably 300-500℃
℃ for 2 minutes or less) to perform a gas phase pyrolysis reaction to form a metal nitride powder.
本発明の方法によれば、磁場の印加により形状異方性を
有する針状の粒子が得られるか、好ましい形状は、短軸
径が５０〜２５０への範囲、長軸径が短軸に対して通常
５倍以上、好ましくは１０〜２５倍である。なお、ここ
で短軸径および長軸径とは所与の粉末について観察され
るそれぞれの平均径を意味する。According to the method of the present invention, acicular particles having shape anisotropy can be obtained by applying a magnetic field.The preferred shape is that the short axis diameter is in the range of 50 to 250 mm, and the long axis diameter is in the range of 50 to 250 mm. It is usually 5 times or more, preferably 10 to 25 times. Note that the minor axis diameter and major axis diameter herein mean respective average diameters observed for a given powder.
磁気特性は飽和磁化が１００〜２００ｅｍｕ／ ｇ。As for magnetic properties, saturation magnetization is 100 to 200 emu/g.
保磁力が８００〜２５００エルステツドの範囲である。The coercive force is in the range of 800 to 2500 oersteds.
上記の窒化遷移金属粉末の形成は、Ｘ線回折あるいは電
子線回折により、その存在を確認することができる。The formation of the transition metal nitride powder described above can be confirmed by X-ray diffraction or electron beam diffraction.
本発明の方法により得られる窒化遷移金属磁性粉は高密
度記録媒体として好ましいものであるが、窒化金属磁性
粉末を要する分野はこれに限られるものではなく、本発
明で得られる窒化金属粉の用途もそれに限られるもので
ない。The transition metal nitride magnetic powder obtained by the method of the present invention is preferable as a high-density recording medium, but the fields requiring the metal nitride magnetic powder are not limited to this, and the applications of the metal nitride powder obtained by the present invention are It is not limited to this.
実施例１
２本の円筒反応管を直列に連結してなる反応装置におい
て、アンモニアで希釈したＦ ｅ （ＣＯ） ５混合気
体を下記の２条件で順次反応に付して、窒化金属磁性粉
を得た。Example 1 In a reaction apparatus consisting of two cylindrical reaction tubes connected in series, a mixture of Fe (CO) 5 diluted with ammonia was subjected to a reaction under the following two conditions in order to form metal nitride magnetic powder. Obtained.
反応条件
第一反応ゾーン
Ｆｅ （Ｃｏ） ・１８体積％
５゛
反応温度＝１３０℃
滞留時間：１５分
第二反応ゾーン
アンモニア二投入Ｆｅ （Ｃｏ）５換算で３体積％とな
るように添加
反応温度、４００℃
滞留時間、２．８秒
直流磁場：６００ガウス
第一反応ゾーンにおける生成物は、元素分析より〔Ｆｅ
（ＣＯ）３ＮＨ〕２の化合物であった。Reaction conditions First reaction zone Fe (Co) ・18 volume % 5゛ Reaction temperature = 130 ° C Residence time: 15 minutes Second reaction zone Ammonia 2 input Fe (Co) Addition reaction temperature so that it becomes 3 volume % in terms of 5 , 400°C residence time, 2.8 seconds DC magnetic field: 600 Gauss The product in the first reaction zone was found to be [Fe
It was a compound of (CO)3NH]2.
得られた窒化金属粉の構造は、Ｘ線スペクトルよりＦ
ｅ ３Ｎであると認められた。磁気特性は、理研電子製
振動型磁力計により測定し、保磁力１．３８００ｅ、飽
和磁化１７５ｅｍｕ／ｇであった。The structure of the obtained metal nitride powder was determined from the X-ray spectrum by F
e It was recognized that it was 3N. The magnetic properties were measured using a vibrating magnetometer manufactured by Riken Denshi, and the coercive force was 1.3800e, and the saturation magnetization was 175 emu/g.
また、この粒子は、軸比は１２で短軸径は１６０人であ
った。Further, this particle had an axial ratio of 12 and a minor axis diameter of 160.
実施例２
実施例１において、Ｆｅ （ＣＯ）５に替えて（Ｃ５Ｈ
５）２Ｆｅを用い下記の２条件で順次反応に付して、窒
化金属磁性粉を得た。Example 2 In Example 1, (C5H
5) Metal nitride magnetic powder was obtained by sequentially reacting with 2Fe under the following two conditions.
反応条件
第一反応ゾーン
（Ｃ２Ｈ５） ２Ｆｅ ： ２０体積％反 応 温
度＝ １７０℃
滞 留 時 間： １５分
第二反応ゾーン
アンモニア：投入（Ｃ２Ｈ５）２Ｆｅ換算で３体積％と
なるように添加
反応温度：４５０℃
滞留時間、２．０秒
直流磁場、６００ガウス
得られた窒化金属粉の構造は、Ｘ線スペクトルよりＦ
ｅ 、Ｎであると認められた。磁気特性は、保磁力１１
５００ｅ、飽和磁化１５４ｅｍｕ／ｇてあった。また、
この粒子は、軸比は１］、平均短軸径は１８０Ａであっ
た。Reaction conditions First reaction zone (C2H5) 2Fe: 20% by volume Reaction Temperature = 170°C Residence time: 15 minutes Second reaction zone Ammonia: Input (C2H5) Addition reaction to give 3% by volume in terms of 2Fe Temperature: 450°C Residence time: 2.0 seconds DC magnetic field: 600 Gauss The structure of the obtained metal nitride powder was determined from the X-ray spectrum by F
e, was recognized as N. The magnetic properties are coercive force 11
500e, and the saturation magnetization was 154 emu/g. Also,
The particles had an axial ratio of 1] and an average minor axis diameter of 180A.
Claims (1)
レックス化合物から選択される有機遷移金属化合物とア
ンモニアとを１００ガウス以上の磁場を印加した気相反
応系において反応させることにより窒化遷移金属磁性粉
末を生成させることを特徴とする磁性粉末の製造法。A transition metal nitride magnetic powder is produced by reacting an organic transition metal compound selected from transition metal carbonyl compounds and transition metal π complex compounds with ammonia in a gas phase reaction system to which a magnetic field of 100 Gauss or more is applied. Characteristic manufacturing method of magnetic powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2112703A JPH0412008A (en) | 1990-04-27 | 1990-04-27 | Production of magnetic powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2112703A JPH0412008A (en) | 1990-04-27 | 1990-04-27 | Production of magnetic powder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0412008A true JPH0412008A (en) | 1992-01-16 |
Family
ID=14593387
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2112703A Pending JPH0412008A (en) | 1990-04-27 | 1990-04-27 | Production of magnetic powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0412008A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100808027B1 (en) * | 2006-08-18 | 2008-02-28 | 한국과학기술연구원 | Fabrication method of nickel nano-powder by gas phase reaction |
| CN105081352A (en) * | 2014-05-07 | 2015-11-25 | 中国科学院宁波材料技术与工程研究所 | Method for growing nanometer particles on substrate |
-
1990
- 1990-04-27 JP JP2112703A patent/JPH0412008A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100808027B1 (en) * | 2006-08-18 | 2008-02-28 | 한국과학기술연구원 | Fabrication method of nickel nano-powder by gas phase reaction |
| CN105081352A (en) * | 2014-05-07 | 2015-11-25 | 中国科学院宁波材料技术与工程研究所 | Method for growing nanometer particles on substrate |
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