JPS5932881B2 - Method for producing ferromagnetic metal powder - Google Patents
Method for producing ferromagnetic metal powderInfo
- Publication number
- JPS5932881B2 JPS5932881B2 JP55140620A JP14062080A JPS5932881B2 JP S5932881 B2 JPS5932881 B2 JP S5932881B2 JP 55140620 A JP55140620 A JP 55140620A JP 14062080 A JP14062080 A JP 14062080A JP S5932881 B2 JPS5932881 B2 JP S5932881B2
- Authority
- JP
- Japan
- Prior art keywords
- borate
- powder
- metal powder
- magnetic
- amount
- 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.)
- Expired
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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
- H01F1/065—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 obtained by a reduction
Description
【発明の詳細な説明】
この発明は記録用強磁性金属粉末の製造方法に関するも
のであり、詳細には高密度磁気記録体に好適な高い保磁
力と高い飽和磁気量および耐酸化性をもつ強磁性純金属
、または強磁性合金の粉末（以下まとめて単に磁性金属
粉と呼び、特段の記載がない場合、金属とは合金も含む
ものとする。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a ferromagnetic metal powder for recording, and in particular, it relates to a method for producing a ferromagnetic metal powder for recording. Powders of magnetic pure metals or ferromagnetic alloys (hereinafter collectively referred to simply as magnetic metal powders, unless otherwise specified, metals include alloys.
）を製造する方法に関するものである。近年、磁気記録
の高密度化に伴い、高保磁力および高飽和磁気量をもつ
磁性金属粉が磁気記録体の記録素子に使用されつつある
が、更にそれらの性能向上が望まれている。). In recent years, with the increase in the density of magnetic recording, magnetic metal powders having high coercive force and high saturation magnetic content are being used in recording elements of magnetic recording bodies, but it is desired to further improve their performance.
この磁性金属粉を製造する方法としては、主として次の
ような方法が検討されている。As a method for manufacturing this magnetic metal powder, the following methods are mainly being considered.
（ハ 金属塩の溶液を次亜リン酸ナトリウム、水素化ホ
ウ素ナトリウムなどで湿式還元する方法（例えば、特公
昭３８−２０５２０号、特開昭４８−７９７５４号、特
公昭５３−１４９１６１号など各公報所載）。(c) A method of wet reduction of a metal salt solution with sodium hypophosphite, sodium borohydride, etc. (for example, Japanese Patent Publication No. 38-20520, Japanese Patent Publication No. 48-79754, Japanese Patent Publication No. 53-149161, etc.) ).
（２）強磁性金属を低圧の不活性ガス中で蒸発させる方
法（例えば、特公昭４７−２７７１８号、特開昭４９−
５２１３４号各公報所載）。(2) A method of evaporating ferromagnetic metal in a low-pressure inert gas (for example, Japanese Patent Publication No. 47-27718, Japanese Patent Application Laid-open No. 49-1989)
No. 52134).
（３）酸化鉄もしくはオキシ水酸化鉄またはこれらに他
の金属（Ｃｏ、Ｎｉなど）を含有せしめたものを還元性
気体で加熱還元する方法（例えば、特公昭３５−３８６
２号、特公昭５４−２２８３８号、特開昭５４−１２２
６６３号の各公報所載）。(3) A method of heating and reducing iron oxide, iron oxyhydroxide, or other metals (Co, Ni, etc.) with a reducing gas (for example,
No. 2, JP 54-22838, JP 54-122
663).
（４）オキシ水酸化鉄または酸化鉄粉末を、シリコーン
オイルを含む液で焼結防止処理した後加熱還元する方法
（特開昭５５−８５６０５号公報所載）。(4) A method in which iron oxyhydroxide or iron oxide powder is subjected to anti-sintering treatment with a liquid containing silicone oil and then heated and reduced (as described in Japanese Patent Laid-Open No. 85605/1983).
しかしながら、上述の製法（１）の湿式法による場合は
、個々の粒子の形状は糸状をしており、結合剤との混合
分散処理の過程においてその粒子が破壊して形状が崩れ
、磁場配向性が悪くなるという欠点を有する。However, in the case of the wet method of manufacturing method (1) described above, the individual particles have a thread-like shape, and during the mixing and dispersion treatment with the binder, the particles break and lose their shape, resulting in poor orientation in the magnetic field. It has the disadvantage that it becomes worse.
また、生成反応は磁界中で行うため、装置を大型化して
大規模に行うことが困難である。また、（２）の蒸発法
による場合も、磁界中で蒸発させることを必要とし、装
置も複雑化するため量産化に向かず、更に価格的に高い
ために工業的に不向きである。Furthermore, since the production reaction is carried out in a magnetic field, it is difficult to increase the size of the apparatus and carry out the production on a large scale. In addition, the evaporation method (2) requires evaporation in a magnetic field and requires complicated equipment, making it unsuitable for mass production, and is also unsuitable for industrial use due to its high price.
一方、（３）の方法は、価格的に安価で量産化に向いて
いるが、還元時に粉末粒子間で焼結して形状変化が生じ
、保磁力が低下するという欠点がある。On the other hand, method (3) is inexpensive and suitable for mass production, but has the drawback that during reduction, powder particles are sintered, resulting in shape changes and a decrease in coercive force.
また、（４）の方法は、多量のシリコーンオイルを用い
ると還元作用が阻害され、少量のシリコーンオイルでは
満足すべき焼結防止効果を表さない。しかもこれらの従
来方法は、いずれも得られた金属粉末を空気中に取出す
に当つては、別途酸化防止処理を要する。そこで本発明
者らは、かかる観点から種々の検討を行なつた結果、オ
キシ水酸化鉄または酸化鉄あるいはこれらに他の金属（
ＣＯ，Ｎｉなど）を含有せしめた粉末をホウ酸エステル
（ホウ酸トリメチル、ホウ酸トリエチル、ホウ酸トリブ
チル、ホウ酸トリフエニルなど）を溶解した溶液中に浸
漬し、ホウ酸エステルを付着処理した後、還元性ガス雰
囲気中で加熱還元すると還元時における粉末粒子間の焼
結を抑制して、これら金属鉄または合金粉末の飽和磁気
モーメントおよび保磁力を著しく向上でき、しかもこれ
ら金属粉末に耐酸化性を付与できるという知見を得て本
発明をなしたものである。Furthermore, in method (4), if a large amount of silicone oil is used, the reducing action is inhibited, and if a small amount of silicone oil is used, a satisfactory sintering prevention effect is not exhibited. Furthermore, all of these conventional methods require a separate oxidation prevention treatment when the obtained metal powder is taken out into the air. Therefore, the present inventors conducted various studies from this point of view and found that iron oxyhydroxide, iron oxide, or other metals (
After immersing powder containing boric acid ester (CO, Ni, etc.) in a solution containing boric acid ester (trimethyl borate, triethyl borate, tributyl borate, triphenyl borate, etc.) and applying the boric acid ester, Heat reduction in a reducing gas atmosphere suppresses sintering between powder particles during reduction, significantly improving the saturation magnetic moment and coercive force of these metal iron or alloy powders, and also imparts oxidation resistance to these metal powders. The present invention was made based on the knowledge that it can be applied.
尚、金属粉末の表面にホウ酸エステルに由来するホウ素
の被膜を形成し、これによつて金属粉末に耐酸化性を付
与する技術については、特願昭５５−８２９６１号（特
開昭５７−９８０２号）として本出願人によつて特許出
願されている通りである。A technique for forming a boron film derived from boric acid ester on the surface of metal powder, thereby imparting oxidation resistance to the metal powder, is disclosed in Japanese Patent Application No. 55-82961 (Japanese Unexamined Patent Publication No. 57-829). No. 9802) by the present applicant.
以下に更に詳細に本発明を説明する。The invention will be explained in more detail below.
本発明で使用される原料粉末としてはα−ＦｅＯＯＨな
どのオキシ水酸化鉄、α−Ｆｅ２Ｏ３などの酸化鉄ある
いはこれらにＣＯ，Ｎｉなどの他の金属を含有せしめた
ものが挙げられるが、これらの粉末は、高保磁力を得る
ために針状のものが適当である。The raw material powders used in the present invention include iron oxyhydroxides such as α-FeOOH, iron oxides such as α-Fe2O3, and those containing other metals such as CO and Ni. The powder is suitably acicular in order to obtain a high coercive force.
上記原料粉末に付着処理するホウ酸エステルとしてはホ
ウ酸トリメチル、ホウ酸トリエチル、ホウ酸トリブチル
、ホウ酸トリフエニル、ホウ酸トリ一ｎ−オクタデシル
、ホウ酸トリ−０−トリル等が好適なものとして挙げら
れ、その他にも適宜選択可能である。Suitable boric acid esters to be attached to the raw material powder include trimethyl borate, triethyl borate, tributyl borate, triphenyl borate, tri-n-octadecyl borate, and tri-0-tolyl borate. Other options can be selected as appropriate.
本発明の粉末を製造するには、ホウ酸エステルを適当な
溶媒に溶解し、その溶液を用いて原料粉末を湿潤または
浸漬し、次いで溶媒を蒸散させた後、還元性ガス中で加
熱還元すればよい。To produce the powder of the present invention, the boric acid ester is dissolved in a suitable solvent, the raw material powder is wetted or immersed in the solution, the solvent is evaporated, and then the powder is heated and reduced in a reducing gas. Bye.
ホウ酸エステルを溶解する適当な溶媒としてはベンゼン
、トルエン、キシレン、ピリジン等の溶ノ媒が挙げられ
るが、取扱い上トルエンを用いたものが好ましい。Suitable solvents for dissolving the boric acid ester include benzene, toluene, xylene, pyridine and the like, but toluene is preferably used for handling reasons.
ホウ酸エステルを使用する量は原料オキシ水酸化物また
は酸化物中の金属原子に対してホウ素原子０．２〜３ａ
ｔ％となる範囲が好適である。The amount of boric acid ester used is 0.2 to 3 boron atoms per metal atom in the raw material oxyhydroxide or oxide.
A range of t% is preferable.
付着量が少いと粉末粒子間で焼結して保磁力が低下する
。付着量が多すぎると還元時の加熱温度を高温にするか
または加熱時間を長時間必要とするだけでなく、原料粉
末の還元が不十分となり飽和磁気量または保磁力が低下
することになる。このようにして、ホウ酸エステルを付
着処理した被還元物を加熱還元する温度範囲は３００〜
５００℃が好適であり、還元温度が低すぎると還元時間
を長時間必要とするだけでなく、還元が不十分となり、
飽和磁気量または保磁力が低下する。If the amount of adhesion is small, sintering occurs between powder particles and the coercive force decreases. If the amount of adhesion is too large, not only will the heating temperature during reduction be high or require a long heating time, but also the reduction of the raw material powder will be insufficient and the saturation magnetic amount or coercive force will decrease. In this way, the temperature range for heating and reducing the material to be reduced to which boric acid ester has been attached is 300~
500°C is suitable; if the reduction temperature is too low, not only will the reduction time be long, but the reduction will be insufficient.
Saturation magnetic amount or coercive force decreases.
還元温度が高すぎると粒子間で焼結して保磁力が低下す
る。以下に実悔例をもつて本発明を具体的に説明する。If the reduction temperature is too high, particles will sinter and the coercive force will decrease. The present invention will be specifically explained below with reference to actual examples.
実晦例 １
長軸約０．６μｍ、軸比：長軸／短軸−１０／１の針状
オキシ水酸化鉄α−ＦｅＯＯＨｌＯ９をホウ酸トリメチ
ルのトルエン溶液にけんだくし、攪拌機でよく分散した
後、約８０℃の温度で溶媒を蒸散し、ホウ酸トリメチル
が付着した粉末を得た。Example 1 Acicular iron oxyhydroxide α-FeOOHlO9 with a long axis of approximately 0.6 μm and an axial ratio of long axis/short axis of -10/1 was suspended in a toluene solution of trimethyl borate and well dispersed with a stirrer. Thereafter, the solvent was evaporated at a temperature of about 80° C. to obtain a powder to which trimethyl borate was attached.
この粉末をニツケル製ボートに入れ、管状電気炉に装填
した。次いで、窒素ガスで空気を置換後、流量４１／Ｍ
ｚｎの水素ガス中で温度を上昇し、４００℃で２時間の
還元を行なつて金属鉄とした。これを室温に下げ再び窒
素ガス雰囲気下でトルエン中に浸漬した。次いで、ろ過
法で空気中に取出し、風乾して磁性粉末を得た。このよ
うな方法で得た試料を、原料に対するホウ酸トリメチル
の使用割合即ち、α−ＦｅＯＯＨｌＯ９中のＦｅ原子数
に対するホウ酸トリメチル中にホウ素原子数の割合によ
つて、下表のように分類する。実帷例 ２
実晦例１においてホウ酸トリメチルの代りにホウ酸トリ
エチルを用いた以外は実晦例１と同様な方法で作製した
試料を、ホウ酸トリエチルの使用実帷例 ３実帷例１に
おいてホウ酸トリメチルの代りにホウ酸トリブチルを用
いた以外は実施例１と同様な方法で作製した試料を、ホ
ウ酸トリブチルの使用量によつて下表のように分類する
。This powder was placed in a nickel boat and loaded into a tubular electric furnace. Then, after replacing the air with nitrogen gas, the flow rate was 41/M.
The temperature was raised in Zn hydrogen gas, and reduction was performed at 400° C. for 2 hours to obtain metallic iron. This was cooled to room temperature and immersed again in toluene under a nitrogen gas atmosphere. Next, it was taken out into the air by a filtration method and air-dried to obtain a magnetic powder. The samples obtained by this method are classified as shown in the table below according to the ratio of trimethyl borate used to the raw material, that is, the ratio of the number of boron atoms in trimethyl borate to the number of Fe atoms in α-FeOOHlO9. . Practical Example 2 A sample prepared in the same manner as in Practical Example 1 except that triethyl borate was used instead of trimethyl borate in Practical Example 1. Practical Example 3 Practical Example 1 Using Triethyl Borate Samples prepared in the same manner as in Example 1 except that tributyl borate was used instead of trimethyl borate were classified according to the amount of tributyl borate used as shown in the table below.
実細例 ４
実帷例１においてホウ酸トリメチルの代りにホウ酸トリ
−ｎ−オクタデシルＢ（ＣＨ３（ＣＨ２）１７０）３を
用いた以外は実圃例１と同様な方法で作製した試料を、
ホウ酸トリ−ｎ−オクタデシルの使用量によつて下表の
ように分類する。Practical Example 4 A sample prepared in the same manner as Practical Example 1 except that tri-n-octadecyl borate B(CH3(CH2)170)3 was used instead of trimethyl borate in Practical Example 1.
Classification is performed according to the amount of tri-n-octadecyl borate used as shown in the table below.
実帷例 ５
実施例１においてホウ酸トリメチルの代りにホウ酸トリ
フエニルＢ（Ｃ６Ｈ５Ｏ）３を用いた以外は実強例１と
同様な方法で作製した試料を、ホウ酸トリフエニルの使
用量によつて下表のように分類する。Practical Example 5 Samples prepared in the same manner as in Practical Example 1 except that triphenyl borate B(C6H5O)3 was used instead of trimethyl borate in Example 1 were treated by varying the amount of triphenyl borate used. Classify as shown in the table below.
実癩例 ６
実帷例１においてホウ酸トリメチルの代りにホウ酸トリ
−０−トリルＢ（ＣＨ３Ｃ６Ｈ４Ｏ）３を用いた以外は
実施例１と同様な方法で作製した試料を、ホウ酸トリ−
０−トリルの使用量によつて下表のように分類する。Leprosy Example 6 A sample prepared in the same manner as in Example 1 except that tri-0-tolyl borate B (CH3C6H4O)3 was used instead of trimethyl borate in Practical Example 1 was treated with tri-borate.
Classified according to the amount of 0-tolyl used as shown in the table below.
実υＤｊ千冫り ７
実帷例２においてα−ＦｅＯＯＨの代りに長軸約０．６
μｍ、軸比：長軸／短軸＝１０／１の酸化鉄α−Ｆｅ２
Ｏ３を用いた以外は実強例２と同様な方法で作製した試
料を、ホウ酸トリエチルの使用量によつて下表のように
分類する。Actual υDj thousand tears 7 In Actual Example 2, the major axis is approximately 0.6 instead of α-FeOOH.
μm, axial ratio: major axis/minor axis = 10/1 iron oxide α-Fe2
Samples prepared in the same manner as in Example 2 except that O3 was used were classified according to the amount of triethyl borate used as shown in the table below.
比較例 １
実晦例１において原料のα−ＦｅＯＯＨに表面処理を行
なわない他は、実帷例１と同様な方法で得た試料をｈと
する。Comparative Example 1 A sample h was obtained in the same manner as in Practical Example 1 except that the raw material α-FeOOH was not subjected to surface treatment.
また、実絶例７において原料のα−Ｆｅ２Ｏ３に表面処
理を行なわない他は実施例７と同様な方法で得た試料を
ｌとする。上記実帷例１〜７および比較例１で得られた
金属鉄粉末の磁気特性を実施例１〜４について表１に、
実帷例５および６について表２に、実帷例７について表
３に、および比較例について表４に夫夫示す。Further, in Example 7, a sample obtained in the same manner as in Example 7 except that the raw material α-Fe2O3 was not subjected to surface treatment is designated as 1. The magnetic properties of the metallic iron powder obtained in Practical Examples 1 to 7 and Comparative Example 1 are shown in Table 1 for Examples 1 to 4.
Examples 5 and 6 are shown in Table 2, Example 7 is shown in Table 3, and Comparative Example is shown in Table 4.
測定は振動試料型磁力計を用い、最高磁界１０，０００
０ｅで行なつた。磁性粉の充填率は約０．６９／ｄであ
る。これらの結果から明らかなように、本発明による金
属磁性粉は比較例１のものに較べ、保磁力および角型比
が大きく、高密度磁気記録媒体の記録素子として良好な
特性を有する。Measurements were made using a vibrating sample magnetometer, with a maximum magnetic field of 10,000
I did it with 0e. The filling rate of the magnetic powder is approximately 0.69/d. As is clear from these results, the metal magnetic powder according to the present invention has a larger coercive force and squareness ratio than that of Comparative Example 1, and has good characteristics as a recording element of a high-density magnetic recording medium.
比較例２および参考例１
実帷例１においてホウ酸トリメチルのトルエン浴液の代
りにシリコーンオイルのエタノール溶液を用いた以外は
実施例１と同様な方法で作製した試料を、ケイ素の量に
よつて下表のように分類する。Comparative Example 2 and Reference Example 1 Samples prepared in the same manner as in Example 1, except that an ethanol solution of silicone oil was used instead of the toluene bath solution of trimethyl borate in Practical Example 1, were prepared according to the amount of silicon. They are classified as shown in the table below.
元処理が困難となる。Original processing becomes difficult.
次に、シリコーンオイルの一定量とホウ素トリメチルの
混合エタノール溶液を用いて更に同様にして試料を作製
した。Next, another sample was prepared in the same manner using a mixed ethanol solution of a certain amount of silicone oil and trimethyl boron.
Claims (1)
ルト、ニッケルその他の金属を含有せしめた粉末の表面
にホウ酸エステルを付着処理した後、還元性ガス雰囲気
中で加熱還元することを特徴とする強磁性金属粉末の製
造方法。1. Ferromagnetism characterized by applying borate ester to the surface of iron oxyhydroxide, iron oxide, or powder containing cobalt, nickel, or other metals, and then reducing the mixture by heating in a reducing gas atmosphere. Method for producing metal powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55140620A JPS5932881B2 (en) | 1980-10-09 | 1980-10-09 | Method for producing ferromagnetic metal powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55140620A JPS5932881B2 (en) | 1980-10-09 | 1980-10-09 | Method for producing ferromagnetic metal powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5764904A JPS5764904A (en) | 1982-04-20 |
| JPS5932881B2 true JPS5932881B2 (en) | 1984-08-11 |
Family
ID=15272937
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP55140620A Expired JPS5932881B2 (en) | 1980-10-09 | 1980-10-09 | Method for producing ferromagnetic metal powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5932881B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100187611B1 (en) * | 1993-12-28 | 1999-06-01 | 오카모토 유지 | Powder mixture for use in pressing to prepare rare earth/iron-based sintered permanent magnet |
| US8911663B2 (en) | 2009-03-05 | 2014-12-16 | Quebec Metal Powders, Ltd. | Insulated iron-base powder for soft magnetic applications |
-
1980
- 1980-10-09 JP JP55140620A patent/JPS5932881B2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5764904A (en) | 1982-04-20 |
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