JPH1064709A - Method of manufacturing manganese-bismuth magnetic powder and magnetic sheet using the powder - Google Patents
Method of manufacturing manganese-bismuth magnetic powder and magnetic sheet using the powderInfo
- Publication number
- JPH1064709A JPH1064709A JP8231419A JP23141996A JPH1064709A JP H1064709 A JPH1064709 A JP H1064709A JP 8231419 A JP8231419 A JP 8231419A JP 23141996 A JP23141996 A JP 23141996A JP H1064709 A JPH1064709 A JP H1064709A
- Authority
- JP
- Japan
- Prior art keywords
- mnbi
- precursor
- magnetic
- magnetic powder
- powder
- 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.)
- Withdrawn
Links
- 239000006247 magnetic powder Substances 0.000 title claims abstract description 47
- 238000004519 manufacturing process Methods 0.000 title claims description 18
- KYAZRUPZRJALEP-UHFFFAOYSA-N bismuth manganese Chemical compound [Mn].[Bi] KYAZRUPZRJALEP-UHFFFAOYSA-N 0.000 title 1
- 239000000843 powder Substances 0.000 title 1
- 229910016629 MnBi Inorganic materials 0.000 claims abstract description 78
- 239000002243 precursor Substances 0.000 claims abstract description 40
- 229910052797 bismuth Inorganic materials 0.000 claims abstract description 22
- 238000005551 mechanical alloying Methods 0.000 claims abstract description 7
- 239000000203 mixture Substances 0.000 claims description 11
- 239000000956 alloy Substances 0.000 claims description 4
- 229910045601 alloy Inorganic materials 0.000 claims description 4
- 239000000758 substrate Substances 0.000 claims description 4
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 abstract description 24
- 238000010298 pulverizing process Methods 0.000 abstract description 20
- 238000010438 heat treatment Methods 0.000 abstract description 17
- 238000000034 method Methods 0.000 abstract description 12
- 238000005303 weighing Methods 0.000 abstract description 2
- 238000001816 cooling Methods 0.000 abstract 1
- 238000007872 degassing Methods 0.000 abstract 1
- 239000002245 particle Substances 0.000 description 10
- 238000006243 chemical reaction Methods 0.000 description 9
- 229920005989 resin Polymers 0.000 description 8
- 239000011347 resin Substances 0.000 description 8
- 230000001133 acceleration Effects 0.000 description 7
- 239000012298 atmosphere Substances 0.000 description 7
- 230000000052 comparative effect Effects 0.000 description 7
- 230000005415 magnetization Effects 0.000 description 6
- 239000002994 raw material Substances 0.000 description 6
- 238000007796 conventional method Methods 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 239000000126 substance Substances 0.000 description 5
- 239000011248 coating agent Substances 0.000 description 4
- 238000000576 coating method Methods 0.000 description 4
- 239000003973 paint Substances 0.000 description 4
- 238000004663 powder metallurgy Methods 0.000 description 4
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 3
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- 239000011230 binding agent Substances 0.000 description 3
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 239000004570 mortar (masonry) Substances 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- 238000003746 solid phase reaction Methods 0.000 description 3
- RZVAJINKPMORJF-UHFFFAOYSA-N Acetaminophen Chemical compound CC(=O)NC1=CC=C(O)C=C1 RZVAJINKPMORJF-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 239000003960 organic solvent Substances 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 229920005749 polyurethane resin Polymers 0.000 description 2
- 239000005297 pyrex Substances 0.000 description 2
- 238000007873 sieving Methods 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 238000001238 wet grinding Methods 0.000 description 2
- RYHBNJHYFVUHQT-UHFFFAOYSA-N 1,4-Dioxane Chemical compound C1COCCO1 RYHBNJHYFVUHQT-UHFFFAOYSA-N 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- NTIZESTWPVYFNL-UHFFFAOYSA-N Methyl isobutyl ketone Chemical compound CC(C)CC(C)=O NTIZESTWPVYFNL-UHFFFAOYSA-N 0.000 description 1
- UIHCLUNTQKBZGK-UHFFFAOYSA-N Methyl isobutyl ketone Natural products CCC(C)C(C)=O UIHCLUNTQKBZGK-UHFFFAOYSA-N 0.000 description 1
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 1
- 229920002433 Vinyl chloride-vinyl acetate copolymer Polymers 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000002216 antistatic agent Substances 0.000 description 1
- 239000012461 cellulose resin Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 125000002243 cyclohexanonyl group Chemical group *C1(*)C(=O)C(*)(*)C(*)(*)C(*)(*)C1(*)* 0.000 description 1
- 238000009837 dry grinding Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000012948 isocyanate Substances 0.000 description 1
- -1 isocyanate compounds Chemical class 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 231100000989 no adverse effect Toxicity 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229920002037 poly(vinyl butyral) polymer Polymers 0.000 description 1
- 229920006267 polyester film Polymers 0.000 description 1
- 229920001228 polyisocyanate Polymers 0.000 description 1
- 239000005056 polyisocyanate Substances 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000008096 xylene Substances 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
【０００１】[0001]
【発明の属する技術分野】この発明は、室温で容易に消
去されることのない情報記録用携帯カ−ドに用いるＭｎ
Ｂｉ磁性粉末の製造方法およびこのＭｎＢｉ磁性粉末を
用いた磁気シ−トに関し、さらに詳しくは、磁気特性に
優れた前記のＭｎＢｉ磁性粉末を短時間で生産性よく製
造する方法と、このＭｎＢｉ磁性粉末を使用したＳ＊が
0.６以上の記録特性に優れた磁気シ−トに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an Mn used for an information recording portable card which is not easily erased at room temperature.
More specifically, the present invention relates to a method for producing a Bi magnetic powder and a magnetic sheet using the MnBi magnetic powder, and more particularly to a method for producing the MnBi magnetic powder having excellent magnetic properties in a short time with high productivity. S * using
The present invention relates to a magnetic sheet having excellent recording characteristics of 0.6 or more.
【０００２】[0002]
【従来の技術】磁気記録媒体は、記録再生が容易である
ためにビデオテ−プ、フロッピ−ディスク、クレジット
カ−ド、プリペイドカ−ド等として広く普及している。
ところが、記録再生が容易であるため、クレジットカ−
ド等では、誤って消去されたり、故意に書き換えられる
等の事故や犯罪が多発している。2. Description of the Related Art Magnetic recording media are widely used as video tapes, floppy disks, credit cards, prepaid cards, and the like because of their easy recording and reproduction.
However, since recording and reproduction are easy, the credit card
Accidents and crimes such as accidental erasure or intentional rewriting have occurred frequently in Japan.
【０００３】そこで、これを防止するため、一旦記録す
ると室温では容易に消去されることがないという特徴を
有するＭｎＢｉ磁性粉末を用いた磁気記録媒体が提案さ
れている。（特公昭５７−３８９６２号、特公昭５４−
３３７２５号、特公昭５２−４６８０１号、特公昭５９
−３１７６４号、特公昭５４−１９２４４号、特公昭５
７−３８９６３号）In order to prevent this, a magnetic recording medium using MnBi magnetic powder has been proposed which has the characteristic that once recorded, it is not easily erased at room temperature. (JP-B-57-38962, JP-B-54-
No. 33725, JP-B-52-46801, JP-B-59
No. 31764, Japanese Patent Publication No. 54-19244, Japanese Patent Publication No. 5
7-38963)
【０００４】[0004]
【発明が解決しようとする課題】ところが、この種のＭ
ｎＢｉ磁性粉末は、従来、原料となるＭｎとＢｉをそれ
ぞれ非酸化性雰囲気の中で１００μｍ程度以下に予め粉
砕し、これを所定量秤量して混合成型をし、さらにこの
成型体を非酸化性雰囲気の中で１０日ないし２０日間加
熱するという粉末冶金的方法によりＭｎＢｉインゴット
を作製した後、湿式粉砕を行って製造されているため、
製造に長時間を要し生産性に劣る。また、成型のときの
形態や圧力分布によってＭｎとＢｉの組成ずれを発生
し、磁気特性の低下を引き起こす可能性がある上、粉砕
前の粒子サイズが大きいこともあって、粒度分布が悪
く、磁気シ−トにした際のＳ＊が悪くて記録特性に劣
る。However, this kind of M
Conventionally, nBi magnetic powder is prepared by previously pulverizing Mn and Bi as raw materials to about 100 μm or less in a non-oxidizing atmosphere, weighing a predetermined amount thereof, mixing and molding, and further molding the molded body with a non-oxidizing material. Since the MnBi ingot is manufactured by a powder metallurgy method of heating for 10 to 20 days in an atmosphere, and then manufactured by wet pulverization,
It takes a long time to manufacture and is inferior in productivity. Further, due to the form and pressure distribution during molding, a composition deviation between Mn and Bi may occur, which may cause a decrease in magnetic properties.In addition, since the particle size before pulverization is large, the particle size distribution is poor, When a magnetic sheet is used, S * is poor and recording characteristics are inferior.
【０００５】この発明は、かかる現状に鑑み、将来的に
ＭｎＢｉ磁性粉末を用いた磁気記録媒体を普及させるた
めには、プロセスの抜本的改良による生産性向上ととも
にＭｎＢｉ磁性粉末の品質のさらなる向上が不可欠と考
えてなされたもので、磁気特性に優れたＭｎＢｉ磁性粉
末を短時間で生産性よく製造する方法を提供し、このＭ
ｎＢｉ磁性粉末を使用して、Ｓ＊が0.６以上の記録特性
に優れた磁気シ−トを得ようとするものである。[0005] In view of the present situation, the present invention requires that the quality of MnBi magnetic powder be further improved in addition to the improvement of productivity by drastic improvement of the process, in order to spread magnetic recording media using MnBi magnetic powder in the future. A method for producing MnBi magnetic powder having excellent magnetic properties in a short period of time and with high productivity was provided.
An object of the present invention is to obtain a magnetic sheet having an S * of 0.6 or more and excellent in recording characteristics using nBi magnetic powder.
【０００６】[0006]
【課題を解決するための手段】この発明のＭｎＢｉ磁性
粉末は、ＭｎとＢｉをメカニカルアロイング法により反
応させてＭｎとＢｉが均一組成のＭｎＢｉ前駆体を得、
このＭｎＢｉ前駆体を加熱して結晶化させた後、微粉砕
して製造される。The MnBi magnetic powder of the present invention is obtained by reacting Mn and Bi by a mechanical alloying method to obtain a MnBi precursor having a uniform composition of Mn and Bi.
The MnBi precursor is heated and crystallized, and then finely pulverized to be manufactured.
【０００７】また、この発明の磁気シ−トは、六方晶Ｍ
ｎＢｉ磁性粉末を、磁気的に配列させて含有させたＳ＊
が0.６以上の磁性層を基体上に設けて構成されている。Further, the magnetic sheet of the present invention has a hexagonal M
S * containing nBi magnetic powder magnetically arranged
Is provided on a substrate with a magnetic layer of 0.6 or more.
【０００８】[0008]
【発明の実施の形態】この発明のＭｎＢｉ磁性粉末は、
原料となるＭｎとＢｉをメカニカルアロイング法（固相
反応）により反応させてＭｎとＢｉが均一組成のＭｎＢ
ｉ前駆体を得、このＭｎＢｉ前駆体を加熱により結晶化
させた後、これを微粉砕して製造される。BEST MODE FOR CARRYING OUT THE INVENTION The MnBi magnetic powder of the present invention comprises:
Mn and Bi as raw materials are reacted by a mechanical alloying method (solid-phase reaction) to obtain MnB having a uniform composition of Mn and Bi.
An i-precursor is obtained, and the MnBi precursor is crystallized by heating and then pulverized.
【０００９】しかして、従来のように、ＭｎとＢｉを予
め粉砕し、次いでプレス機により成型した後、これを加
熱してＭｎＢｉインゴットを作製し、これを粉砕して製
造されるＭｎＢｉ磁性粉末とは異なり、出発原料がＭｎ
とＢｉをメカニカルアロイング法（固相反応）により反
応させて得られたＭｎとＢｉが均一組成のＭｎＢｉ前駆
体であるため、磁気特性に優れたＭｎＢｉ磁性粉末が短
時間で生産性よく製造され、このＭｎＢｉ磁性粉末を使
用すると、Ｓ＊が0.６以上の記録特性に優れた磁気シ−
トが得られる。However, as in the prior art, Mn and Bi are preliminarily pulverized, then molded by a press machine, and then heated to produce an MnBi ingot. Is different and the starting material is Mn
Mn and Bi obtained by reacting Ni and Bi by a mechanical alloying method (solid phase reaction) are MnBi precursors having a uniform composition, so that MnBi magnetic powder having excellent magnetic properties can be produced in a short time with high productivity. When this MnBi magnetic powder is used, a magnetic screen having an excellent recording characteristic of S * of 0.6 or more is obtained.
Is obtained.
【００１０】以下、この発明のＭｎＢｉ磁性粉末の製造
方法を、ＭｎとＢｉをメカニカルアロイング法（固相反
応）により反応させてＭｎとＢｉが均一組成のＭｎＢｉ
前駆体を得る工程と、このＭｎＢｉ前駆体を加熱により
結晶化させる工程と、この結晶化させたＭｎＢｉ前駆体
を微粉砕する工程に分け、工程順に従って説明する。In the following, the method for producing MnBi magnetic powder of the present invention comprises reacting Mn and Bi by a mechanical alloying method (solid phase reaction) to obtain MnBi having a uniform composition.
The steps of obtaining the precursor, the step of crystallizing the MnBi precursor by heating, and the step of pulverizing the crystallized MnBi precursor will be described in the order of the steps.
【００１１】＜ＭｎとＢｉが均一組成のＭｎＢｉ前駆体
を得る工程＞原料として用意したＭｎとＢｉとを秤量
し、ボ−ルミル等の乾式の粉砕機に入れ、非酸化性雰囲
気中で機械的に反応させて行われ、反応時間は装置の種
類、付加エネルギ−により異なるが、最大遠心力加速度
１５０Ｇを発生することができる遊星ボ−ルミルでは、
遠心力加速度１５０Ｇで１時間でよく、このメカニカル
アロイング反応によりＭｎとＢｉが均一組成のＭｎＢｉ
前駆体が得られる。<Step of Obtaining MnBi Precursor Having Uniform Composition of Mn and Bi> Mn and Bi prepared as raw materials are weighed, placed in a dry pulverizer such as a ball mill, and subjected to mechanical treatment in a non-oxidizing atmosphere. Although the reaction time varies depending on the type of the apparatus and the added energy, in a planetary ball mill capable of generating a maximum centrifugal acceleration of 150 G,
A centrifugal acceleration of 150 G is sufficient for 1 hour, and MnBi having a uniform composition of Mn and Bi by this mechanical alloying reaction.
A precursor is obtained.
【００１２】＜ＭｎＢｉ前駆体を加熱により結晶化させ
る工程＞前記のＭｎＢｉ前駆体を得た段階で、すでにあ
る程度の反応が起こっているため、２６０℃ないし３４
０℃で５分間ないし１０分間加熱して行われる。この加
熱で結晶化されたＭｎＢｉ前駆体の結晶子サイズは７０
０Å〜２０００Åの範囲内であることが好ましい。<Step of Crystallizing MnBi Precursor by Heating> At the stage when the above-mentioned MnBi precursor is obtained, a certain degree of reaction has already taken place.
Heating is performed at 0 ° C. for 5 to 10 minutes. The crystallite size of the MnBi precursor crystallized by this heating is 70
It is preferable that the angle be in the range of 0 ° to 2000 °.
【００１３】このような加熱を行う場合、従来の粉末冶
金法による場合は、加熱温度を高くしすぎてＢｉが溶融
するとそれ以上反応が進行しにくくなるため、加熱温度
としてはＢｉの融点直下の温度である２６５℃から２７
０℃が好ましく、Ｂｉの融点以上に加熱しないように厳
密にコントロ−ルする必要があるが、前記のＭｎＢｉ前
駆体は、すでにＭｎとＢｉが均一に混じっているため反
応が即座に終了する。従って、この場合、Ｂｉの融点以
上に加熱されても悪影響を及ぼさないという利点を有す
る。In the case of performing such heating, in the case of the conventional powder metallurgy method, if the heating temperature is too high and Bi is melted, the reaction hardly proceeds further, so that the heating temperature is just below the melting point of Bi. Temperature from 265 ° C to 27
The temperature is preferably 0 ° C., and it is necessary to strictly control the temperature so as not to exceed the melting point of Bi. However, in the above-mentioned MnBi precursor, the reaction is immediately terminated because Mn and Bi are already uniformly mixed. Therefore, in this case, there is an advantage that even if heated to a temperature higher than the melting point of Bi, there is no adverse effect.
【００１４】＜結晶化させたＭｎＢｉ前駆体を微粉砕す
る工程＞結晶化の終わったＭｎＢｉ前駆体は、次いで、
ボ−ルミル、遊星ボ−ルミル等を用いた湿式粉砕法、あ
るいはジェットミル等を用いた乾式粉砕法によりμｍオ
−ダ−の微粒子に微粉砕される。<Step of Finely Pulverizing the Crystallized MnBi Precursor> The crystallized MnBi precursor is then
The particles are finely pulverized into fine particles of the order of μm by a wet pulverization method using a ball mill, a planetary ball mill or the like, or a dry pulverization method using a jet mill or the like.
【００１５】ここで、粉末冶金法によって得たＭｎＢｉ
インゴットを粉砕する従来の方法では、インゴットのサ
イズが大きく、また結晶性が高くないため、極めて高い
エネルギ−を加えて粉砕する必要があるが、このＭｎＢ
ｉ前駆体を微粉砕する方法では、すでに粒子サイズが数
μｍから１００μｍ程度と小さいため、粉砕の程度は粉
末冶金法による場合に比べて弱くても充分であり、その
結果、欠陥が少なく、均一なＭｎＢｉ磁性粉末が得られ
る。Here, MnBi obtained by powder metallurgy is used.
In the conventional method of pulverizing an ingot, since the size of the ingot is large and the crystallinity is not high, it is necessary to pulverize the ingot by applying extremely high energy.
In the method of pulverizing the i-precursor, since the particle size is already as small as about several μm to about 100 μm, the degree of pulverization is sufficient even if weaker than in the case of the powder metallurgy method. MnBi magnetic powder is obtained.
【００１６】粉砕手段としては、ボ−ルミル、遊星ボ−
ルミル等を用いた湿式粉砕法、あるいはジェットミル等
を用いた乾式粉砕法など従来より汎用されている手段を
使用することができ、湿式粉砕法による場合の液体とし
てはトルエン等の水を含まない溶剤が用いられる。ま
た、乾式粉砕法による場合は、不活性ガス雰囲気にして
行われる。Ball mills, planetary balls, etc.
A conventional method such as a wet milling method using a dry mill or a dry milling method using a jet mill or the like can be used, and the liquid in the case of the wet milling method does not include water such as toluene. A solvent is used. In the case of the dry pulverization method, the drying is performed in an inert gas atmosphere.
【００１７】粉砕後の平均粒子サイズは0.０５〜３μｍ
になるように粉砕条件によりコントロ−ルするのが好ま
しく、粒子サイズが0.０５μｍより小さいと最終的に得
られるＭｎＢｉ磁性粉末が充分な磁気特性を示さなくな
り、３μｍを超えると最終的に得られるＭｎＢｉ磁性粉
末を用いた磁気シ−トの磁性層の表面平滑性が低下し、
充分な記録が行えない。The average particle size after pulverization is 0.05 to 3 μm.
It is preferable to control the milling conditions so that the particle size is smaller than 0.05 μm, the finally obtained MnBi magnetic powder does not show sufficient magnetic properties, and the particle size is more than 3 μm. The surface smoothness of the magnetic layer of the magnetic sheet using the MnBi magnetic powder is reduced,
Not enough recording.
【００１８】以上の工程により、１５０時間以内で、飽
和磁化が２０ｅｍｕ／ｇ以上あり、保磁力が３０００〜
１５０００エルステッドのＭｎＢｉ磁性粉末が得られ
る。According to the above steps, the saturation magnetization is 20 emu / g or more and the coercive force is 3000 to
15,000 Oersted of MnBi magnetic powder is obtained.
【００１９】なお、ＭｎＢｉ前駆体を加熱により結晶化
させる工程と、結晶化させたＭｎＢｉ前駆体を微粉砕す
る工程の順序は逆であってもよく、ＭｎとＢｉがほぼ均
一に混ざり合ったＭｎＢｉ前駆体をまず微粉砕し、次に
これを加熱させることにより結晶化させてもよい。The order of the step of crystallizing the MnBi precursor by heating and the step of finely pulverizing the crystallized MnBi precursor may be reversed, and MnBi in which Mn and Bi are almost uniformly mixed. The precursor may be first pulverized and then crystallized by heating.
【００２０】このような順序でＭｎＢｉ前駆体をまず微
粉砕し、次にこれを加熱させて結晶化させると、粉砕に
より生じたいびつな形状や結晶中の歪みが加熱によりあ
る程度除去されるため、粒子の機械的性質、塗料特性、
磁気的性質がより好ましく改善される場合があり、この
ような効果を発現させるためには、ＭｎとＢｉとがより
均一に混合した組成のＭｎＢｉ前駆体としておく必要が
ある。When the MnBi precursor is first pulverized in this order, and then heated to crystallize, the irregular shape caused by the pulverization and the distortion in the crystal are removed to some extent by heating. Mechanical properties of the particles, paint properties,
In some cases, the magnetic properties are more preferably improved, and in order to exert such an effect, it is necessary to prepare a MnBi precursor having a composition in which Mn and Bi are more uniformly mixed.
【００２１】また、粉砕後は、酸素を微量含む不活性ガ
ス雰囲気中で、加熱する等により、表面に安定な酸化被
膜を形成することが好ましい。After the pulverization, it is preferable to form a stable oxide film on the surface by heating or the like in an inert gas atmosphere containing a small amount of oxygen.
【００２２】このようなＭｎＢｉ合金磁性粉末を用いた
磁気シ−トは、常法に準じて作製され、たとえば、Ｍｎ
Ｂｉ磁性粉末を、結合剤樹脂、有機溶剤などとともに混
合分散して磁性塗料を調製し、これを基体上に塗布、乾
燥して作製される。なお、磁性塗料を基体上に塗布した
後、磁性層面に対して平行に磁場を印加して磁場配向を
行うのが好ましい。A magnetic sheet using such MnBi alloy magnetic powder is produced according to a conventional method.
A magnetic coating material is prepared by mixing and dispersing Bi magnetic powder with a binder resin, an organic solvent, and the like, and the magnetic coating material is applied to a substrate and dried to prepare a magnetic coating material. It is preferable that after applying the magnetic paint on the substrate, a magnetic field is applied in parallel to the surface of the magnetic layer to perform magnetic field orientation.
【００２３】ここで、結合剤樹脂としては、一般に磁気
記録媒体に用いられているものがいずれも使用され、た
とえば、塩化ビニル−酢酸ビニル系共重合体、ポリビニ
ルブチラ−ル樹脂、繊維素系樹脂、フッ素系樹脂、ポリ
ウレタン系樹脂、イソシアネ−ト化合物、放射線硬化型
樹脂などが用いられる。Here, as the binder resin, any resin generally used for magnetic recording media is used, for example, a vinyl chloride-vinyl acetate copolymer, a polyvinyl butyral resin, a cellulose resin Resins, fluorine resins, polyurethane resins, isocyanate compounds, radiation-curable resins and the like are used.
【００２４】また、有機溶剤としては、シクロヘキサノ
ン、メチルエチルケトン、メチルイソブチルケトン、酢
酸エチル、ベンゼン、トルエン、キシレン、テトラヒド
ロフラン、ジオキサンなど、使用する結合剤樹脂を溶解
するのに適した溶剤が、特に制限されることなく単独ま
たは二種以上混合して使用される。As the organic solvent, solvents suitable for dissolving the binder resin to be used, such as cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, benzene, toluene, xylene, tetrahydrofuran and dioxane, are particularly limited. Used alone or in combination of two or more.
【００２５】なお、磁性塗料中には、通常使用されてい
る各種添加剤、たとえば、潤滑剤、研磨剤、帯電防止剤
などを任意に添加使用してもよい。The magnetic coating material may optionally contain various commonly used additives such as a lubricant, an abrasive, an antistatic agent and the like.
【００２６】[0026]
【実施例】次に、この発明の実施例について説明する。 実施例１ Ｍｎ（フルウチ化学社製；純度９9.９％）、Ｂｉ（フル
ウチ化学社製；純度９9.９％）を用いて、Ｍｎを１００
ｇ、Ｂｉを３８０ｇ秤量し、これを遊星ボ−ルミル（栗
本鉄工所社製）に入れ真空脱気後Ａｒガスにて置換し、
遠心加速度１５０Ｇにて１時間機械的に反応させた。そ
の後、不活性タンク中に取り出し、分級することにより
サイズが１００μｍ以下のＭｎＢｉ前駆体を得た。Next, an embodiment of the present invention will be described. Example 1 Using Mn (manufactured by Furuuchi Chemical Co .; purity: 99.9%) and Bi (manufactured by Furuuchi Chemical Co .; purity: 99.9%), Mn was reduced to 100.
g and Bi were weighed in an amount of 380 g, placed in a planetary ball mill (manufactured by Kurimoto Iron Works), vacuum-degassed, and replaced with Ar gas.
A mechanical reaction was performed at a centrifugal acceleration of 150 G for 1 hour. Then, it was taken out into an inert tank and classified to obtain a MnBi precursor having a size of 100 μm or less.
【００２７】次に、得られたＭｎＢｉ前駆体を、雰囲気
電気炉を用いて窒素ガス気流中３００℃で２時間加熱
後、室温にまで冷却して取り出した。Next, the obtained MnBi precursor was heated in a nitrogen gas stream at 300 ° C. for 2 hours using an atmosphere electric furnace, and then cooled to room temperature and taken out.
【００２８】次いで、加熱の終わったＭｎＢｉ前駆体を
遊星ボ−ルミルを用いてトルエン中で、３０Ｇで２時間
湿式粉砕した。Then, the heated MnBi precursor was wet-milled at 30 G for 2 hours in toluene using a planetary ball mill.
【００２９】粉砕後、トルエンを除去し１０００ｐｐｍ
の酸素を含む窒素気流中で、８０℃で２時間加熱し、さ
らに室温に１２時間保持し、表面に酸化被膜を形成して
安定化した。このようにして得られたＭｎＢｉ磁性粉末
の平均粒径は約２μｍであり、ＶＳＭを用いて測定した
磁気特性は、保磁力が９４００エルステッド、飽和磁化
が４４ｅｍｕ／ｇ、最大印加磁界は１６Ｋエルステッド
であった。After pulverization, toluene was removed and 1000 ppm
Was heated at 80 ° C. for 2 hours in a nitrogen gas stream containing oxygen and kept at room temperature for 12 hours to form an oxide film on the surface and stabilized. The MnBi magnetic powder thus obtained has an average particle size of about 2 μm. The magnetic properties measured using a VSM are as follows: a coercive force of 9400 Oersted, a saturation magnetization of 44 emu / g, and a maximum applied magnetic field of 16 K Oersted. there were.
【００３０】以上のようにして得られたＭｎＢｉ磁性粉
末を使用し、 ＭｎＢｉ合金磁性粉末 １００重量部 ポリウレタン樹脂 ２０ 〃 （大日本インキ化学工業社製；Ｔ−５２５０） シクロヘキサノン １１５ 〃 トルエン １１５ 〃 の組成物をサンドグラインダ−ミルで充分に混練分散さ
せた後、多官能性ポリイソシアネ−ト化合物（日本ポリ
ウレタン工業社製；コロネ−トＬ）を５重量部加えて磁
性塗料を調製した。この磁性塗料を厚さ７５μｍのポリ
エステルフィルム上に、乾燥後の厚さが２０μｍとなる
ように塗布し、１０ｋエルステッドの長手方向の配向磁
場を印加しながら乾燥させて磁性層を形成し、磁気シ−
トを作製した。Using the MnBi magnetic powder obtained as described above, MnBi alloy magnetic powder 100 parts by weight Polyurethane resin 20〃 (manufactured by Dainippon Ink and Chemicals, Inc .; T-5250) Composition of cyclohexanone 115〃toluene 115〃 After sufficiently kneading and dispersing the product with a sand grinder mill, 5 parts by weight of a polyfunctional polyisocyanate compound (manufactured by Nippon Polyurethane Industry Co., Ltd .; Colonate L) was added to prepare a magnetic paint. This magnetic paint is applied on a 75 μm-thick polyester film so that the thickness after drying becomes 20 μm, and dried while applying a longitudinal orientation magnetic field of 10 kOersted to form a magnetic layer. −
Was made.
【００３１】実施例２ 実施例１におけるＭｎＢｉ前駆体の調製において、分級
することにより３００μｍサイズのＭｎＢｉ前駆体を得
た以外は、実施例１と同様にしてＭｎＢｉ前駆体を得、
これを原料として使用し、実施例１と同様にしてＭｎＢ
ｉ磁性粉末を製造し、磁気シ−トを作製した。Example 2 In the preparation of the MnBi precursor in Example 1, an MnBi precursor was obtained in the same manner as in Example 1, except that a MnBi precursor having a size of 300 μm was obtained by classification.
Using this as a raw material, MnB was used in the same manner as in Example 1.
An i-magnetic powder was produced to produce a magnetic sheet.
【００３２】実施例３ 実施例１におけるＭｎＢｉ前駆体の調製において、遠心
加速度１５０Ｇにて１時間機械的に反応させる代わり
に、遠心加速度１５０Ｇにて２時間機械的に反応させた
以外は、実施例１と同様にしてＭｎＢｉ前駆体を得、こ
れを原料として使用し、実施例１と同様にして、ＭｎＢ
ｉ磁性粉末を製造し、磁気シ−トを作製した。Example 3 In the preparation of the MnBi precursor in Example 1, the mechanical reaction was performed at a centrifugal acceleration of 150 G for 2 hours instead of the mechanical reaction at a centrifugal acceleration of 150 G for 1 hour. MnBi precursor was obtained in the same manner as in Example 1, and this was used as a raw material.
An i-magnetic powder was produced to produce a magnetic sheet.
【００３３】実施例４ 実施例１におけるＭｎＢｉ前駆体の調製において、遠心
加速度１５０Ｇにて１時間機械的に反応させる代わり
に、遠心加速度１００Ｇにて２時間機械的に反応させた
以外は、実施例１と同様にしてＭｎＢｉ前駆体を得、こ
れを原料として使用し、実施例１と同様にして、ＭｎＢ
ｉ磁性粉末を製造し、磁気シ−トを作製した。Example 4 In the preparation of the MnBi precursor in Example 1, the mechanical reaction was performed at a centrifugal acceleration of 100 G for 2 hours instead of the mechanical reaction at a centrifugal acceleration of 150 G for 1 hour. MnBi precursor was obtained in the same manner as in Example 1, and this was used as a raw material.
An i-magnetic powder was produced to produce a magnetic sheet.
【００３４】比較例１ Ｂｉ（フルウチ化学社製；純度９9.９％）、Ｍｎ（フル
ウチ化学社製；純度９9.９％）を乳鉢を用いて粉砕し、
１００メッシュのふるい掛けをした後、Ｍｎを１００
ｇ、Ｂｉを３８０ｇ秤量し、乳鉢を用いて充分に混合し
た。Comparative Example 1 Bi (manufactured by Furuuchi Chemical Co .; purity: 99.9%) and Mn (manufactured by Furuuchi Chemical Co .; purity: 99.9%) were ground using a mortar.
After sieving 100 mesh, Mn was 100
g and Bi were weighed in an amount of 380 g and sufficiently mixed using a mortar.
【００３５】次に、これを加圧プレス機を用いて３ｔ／
ｃｍ2 の圧力で直径×長さが６ｍｍ×６ｍｍの円柱状に
成型し、この成型体をパイレックスガラス管に真空封入
し、電気炉中にて２６５℃で１０日間熱処理して、Ｍｎ
Ｂｉインゴットを作製した。Next, this was subjected to 3 t /
It was molded into a cylinder having a diameter of 6 mm x 6 mm in diameter at a pressure of 2 cm2, and the molded body was vacuum-sealed in a Pyrex glass tube and heat-treated at 265 ° C for 10 days in an electric furnace to obtain Mn.
A Bi ingot was produced.
【００３６】次いで、得られたＭｎＢｉインゴットをグ
ロ−ボックスを使用し、不活性雰囲気中で乳鉢を用いて
粗粉砕し、さらに、遊星ボ−ルミルを用いてトルエン中
にて、２００ｒｐｍで２時間粉砕した後、実施例１と同
様に気相酸化による安定化処理を施した。このようにし
て得られたＭｎＢｉ磁性粉末の平均粒径は約２μｍであ
り、ＶＳＭを用いて測定した磁気特性は、保磁力が８５
００エルステッド、飽和磁化が３４ｅｍｕ／ｇ、最大印
加磁界は１６Ｋエルステッドであった。Next, the obtained MnBi ingot was coarsely pulverized using a mortar in an inert atmosphere using a glove box, and further pulverized in toluene using a planetary ball mill at 200 rpm for 2 hours. After that, a stabilization treatment by vapor phase oxidation was performed in the same manner as in Example 1. The average particle size of the MnBi magnetic powder thus obtained is about 2 μm, and the magnetic characteristics measured using a VSM indicate that the coercive force is 85 μm.
00 Oersted, the saturation magnetization was 34 emu / g, and the maximum applied magnetic field was 16 K Oersted.
【００３７】このようにして得られたＭｎＢｉ磁性粉末
を使用し、実施例１と同様にして磁気シ−トを作製し
た。Using the MnBi magnetic powder thus obtained, a magnetic sheet was produced in the same manner as in Example 1.
【００３８】比較例２ 比較例１において、１００メッシュのふるい掛けをした
後のＭｎとＢｉを混合し、これをそのままパイレックス
ガラス管に真空封入した以外は、比較例１と同様にして
ＭｎＢｉインゴットを作製し、ＭｎＢｉ磁性粉末を得
た。また、このようにして得られたＭｎＢｉ磁性粉末を
使用し、実施例１と同様にして磁気シ−トを作製した。Comparative Example 2 A MnBi ingot was prepared in the same manner as in Comparative Example 1 except that Mn and Bi after sieving with 100 mesh were mixed and the mixture was directly vacuum-sealed in a Pyrex glass tube. It produced and obtained MnBi magnetic powder. Using the MnBi magnetic powder thus obtained, a magnetic sheet was produced in the same manner as in Example 1.
【００３９】各実施例で得られたＭｎＢｉ前駆体の結晶
子サイズを、Ｘ線回析を行ってシェラ−の式から求め
た。また、各実施例および比較例で得られたＭｎＢｉの
加熱後の飽和磁化、微粉砕後の飽和磁化、微粉砕後の保
磁力および製造時間を測定した。さらに、各実施例およ
び比較例で得られた磁気シ−トについて、Ｓ＊を従来の
方法にて測定した。下記表１はその結果である。The crystallite size of the MnBi precursor obtained in each of the examples was determined by X-ray diffraction using the Scherrer equation. Further, the saturation magnetization after heating, the saturation magnetization after fine pulverization, the coercive force after fine pulverization, and the production time of the MnBi obtained in each of the examples and comparative examples were measured. Further, S * was measured by a conventional method for the magnetic sheets obtained in each of Examples and Comparative Examples. Table 1 below shows the results.
【００４０】 [0040]
【００４１】[0041]
【発明の効果】上記表１から明らかなように、この発明
のＭｎＢｉ磁性粉末の製造方法（実施例１〜４）では、
従来のＭｎＢｉ磁性粉末の製造方法（比較例１〜２）に
比べて、製造時間がはるかに短く、また得られたＭｎＢ
ｉ磁性粉末の飽和磁化および保磁力が高く、このことか
らこの発明の製造方法によれば、短時間で生産性よく磁
気特性に優れたＭｎＢｉ磁性粉末が得られることがわか
る。As is clear from the above Table 1, in the method for producing MnBi magnetic powder of the present invention (Examples 1 to 4),
The production time is much shorter than the conventional method for producing MnBi magnetic powder (Comparative Examples 1 and 2), and the obtained MnBi
The saturation magnetization and the coercive force of the i-magnetic powder are high, which indicates that the production method of the present invention can provide a MnBi magnetic powder excellent in magnetic properties with good productivity in a short time.
【００４２】また、この発明の製造方法で得られたＭｎ
Ｂｉ磁性粉末を用いた磁気シ−ト（実施例１〜４）は、
従来の製造方法で得られたＭｎＢｉ磁性粉末を用いた磁
気シ−ト（比較例１〜２）に比べてＳ＊が0.６以上で高
く、このことからこの発明の製造方法で得られたＭｎＢ
ｉ磁性粉末を用いた磁気シ−トは、Ｓ＊が0.６以上で記
録特性に優れていることがわかる。The Mn obtained by the production method of the present invention
The magnetic sheets using Bi magnetic powder (Examples 1 to 4)
Compared with the magnetic sheet using the MnBi magnetic powder obtained by the conventional manufacturing method (Comparative Examples 1 and 2), S * was 0.6 or higher, which was high by the manufacturing method of the present invention. MnB
It can be seen that the magnetic sheet using the i-magnetic powder has excellent recording characteristics when S * is 0.6 or more.
Claims (5)
より反応させてＭｎとＢｉが均一組成のＭｎＢｉ前駆体
を得、このＭｎＢｉ前駆体を加熱して結晶化させた後、
微粉砕して六方晶ＭｎＢｉ磁性粉末とすることを特徴と
するＭｎＢｉ磁性粉末の製造方法。1. Mn and Bi are reacted by a mechanical alloying method to obtain a MnBi precursor having a uniform composition of Mn and Bi, and the MnBi precursor is heated and crystallized.
A method for producing MnBi magnetic powder, which is pulverized to obtain hexagonal MnBi magnetic powder.
する粉末状の合金である請求項１記載のＭｎＢｉ磁性粉
末の製造方法。2. The method for producing MnBi magnetic powder according to claim 1, wherein the MnBi precursor is a powdery alloy containing Mn and Bi as main components.
の結晶子サイズが７００Å以上２０００Å以下である請
求項２記載のＭｎＢｉ磁性粉末の製造方法。3. The method for producing MnBi magnetic powder according to claim 2, wherein the crystallite size of the powdery alloy containing Mn and Bi as main components is 700 ° or more and 2000 ° or less.
間以内である請求項１記載のＭｎＢｉ磁性粉末の製造方
法。4. The method for producing a MnBi magnetic powder according to claim 1, wherein the production time of the MnBi magnetic powder is 150 hours or less.
ＭｎＢｉ磁性粉末を磁気的に配列させて含有させたＳ＊
が0.６以上の磁気シ−ト。5. An S * in which hexagonal MnBi magnetic powder is magnetically arranged and contained in a magnetic layer provided on a substrate.
Is a magnetic sheet of 0.6 or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8231419A JPH1064709A (en) | 1996-08-12 | 1996-08-12 | Method of manufacturing manganese-bismuth magnetic powder and magnetic sheet using the powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8231419A JPH1064709A (en) | 1996-08-12 | 1996-08-12 | Method of manufacturing manganese-bismuth magnetic powder and magnetic sheet using the powder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH1064709A true JPH1064709A (en) | 1998-03-06 |
Family
ID=16923298
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8231419A Withdrawn JPH1064709A (en) | 1996-08-12 | 1996-08-12 | Method of manufacturing manganese-bismuth magnetic powder and magnetic sheet using the powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH1064709A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102615318A (en) * | 2012-04-11 | 2012-08-01 | 景旺电子（深圳）有限公司 | Routing method for PCB (printed circuit board) |
| JP2015055010A (en) * | 2013-09-12 | 2015-03-23 | トヨタ モーター エンジニアリング アンド マニュファクチャリング ノース アメリカ，インコーポレイティド | METHOD OF PREPARING MANGANESE-BISMUTH ALLOY NANOPARTICLE, MnBi NANOPARTICLE AND HARD MAGNET CONTAINING THE SAME |
-
1996
- 1996-08-12 JP JP8231419A patent/JPH1064709A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102615318A (en) * | 2012-04-11 | 2012-08-01 | 景旺电子（深圳）有限公司 | Routing method for PCB (printed circuit board) |
| JP2015055010A (en) * | 2013-09-12 | 2015-03-23 | トヨタ モーター エンジニアリング アンド マニュファクチャリング ノース アメリカ，インコーポレイティド | METHOD OF PREPARING MANGANESE-BISMUTH ALLOY NANOPARTICLE, MnBi NANOPARTICLE AND HARD MAGNET CONTAINING THE SAME |
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| A300 | Application deemed to be withdrawn because no request for examination was validly filed |
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