JPS634007A - Production of fine hexagonal cobalt particles - Google Patents
Production of fine hexagonal cobalt particlesInfo
- Publication number
- JPS634007A JPS634007A JP14604986A JP14604986A JPS634007A JP S634007 A JPS634007 A JP S634007A JP 14604986 A JP14604986 A JP 14604986A JP 14604986 A JP14604986 A JP 14604986A JP S634007 A JPS634007 A JP S634007A
- Authority
- JP
- Japan
- Prior art keywords
- cobalt
- fine particles
- reaction
- hexagonal
- solvent
- 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
- 229910017052 cobalt Inorganic materials 0.000 title claims abstract description 61
- 239000010941 cobalt Substances 0.000 title claims abstract description 61
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 title claims abstract description 45
- 239000002245 particle Substances 0.000 title claims abstract description 20
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 230000005291 magnetic effect Effects 0.000 claims abstract description 16
- 239000002904 solvent Substances 0.000 claims abstract description 13
- 239000002736 nonionic surfactant Substances 0.000 claims abstract description 8
- 125000005907 alkyl ester group Chemical group 0.000 claims abstract description 6
- 150000001732 carboxylic acid derivatives Chemical class 0.000 claims abstract description 6
- 239000000696 magnetic material Substances 0.000 claims abstract description 5
- 239000010419 fine particle Substances 0.000 claims description 32
- 238000000034 method Methods 0.000 claims description 16
- 125000004432 carbon atom Chemical group C* 0.000 claims description 3
- 238000006243 chemical reaction Methods 0.000 description 31
- -1 Co)+h can be used Chemical group 0.000 description 13
- 239000006247 magnetic powder Substances 0.000 description 11
- 239000013078 crystal Substances 0.000 description 10
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 9
- 239000002202 Polyethylene glycol Substances 0.000 description 9
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 9
- 229910002091 carbon monoxide Inorganic materials 0.000 description 9
- 229920001223 polyethylene glycol Polymers 0.000 description 9
- 230000005415 magnetization Effects 0.000 description 5
- 239000000843 powder Substances 0.000 description 5
- 239000002994 raw material Substances 0.000 description 5
- 239000004094 surface-active agent Substances 0.000 description 5
- RFVNOJDQRGSOEL-UHFFFAOYSA-N 2-hydroxyethyl octadecanoate Chemical compound CCCCCCCCCCCCCCCCCC(=O)OCCO RFVNOJDQRGSOEL-UHFFFAOYSA-N 0.000 description 4
- DKPFZGUDAPQIHT-UHFFFAOYSA-N Butyl acetate Natural products CCCCOC(C)=O DKPFZGUDAPQIHT-UHFFFAOYSA-N 0.000 description 4
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- MQIKJSYMMJWAMP-UHFFFAOYSA-N dicobalt octacarbonyl Chemical group [Co+2].[Co+2].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-] MQIKJSYMMJWAMP-UHFFFAOYSA-N 0.000 description 4
- FUZZWVXGSFPDMH-UHFFFAOYSA-N hexanoic acid Chemical compound CCCCCC(O)=O FUZZWVXGSFPDMH-UHFFFAOYSA-N 0.000 description 4
- 239000012442 inert solvent Substances 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
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- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 3
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 229910002090 carbon oxide Inorganic materials 0.000 description 3
- 150000001733 carboxylic acid esters Chemical class 0.000 description 3
- 238000000354 decomposition reaction Methods 0.000 description 3
- 239000011553 magnetic fluid Substances 0.000 description 3
- CXWXQJXEFPUFDZ-UHFFFAOYSA-N tetralin Chemical compound C1=CC=C2CCCCC2=C1 CXWXQJXEFPUFDZ-UHFFFAOYSA-N 0.000 description 3
- 238000005979 thermal decomposition reaction Methods 0.000 description 3
- CMCBDXRRFKYBDG-UHFFFAOYSA-N 1-dodecoxydodecane Chemical compound CCCCCCCCCCCCOCCCCCCCCCCCC CMCBDXRRFKYBDG-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- FERIUCNNQQJTOY-UHFFFAOYSA-N Butyric acid Chemical compound CCCC(O)=O FERIUCNNQQJTOY-UHFFFAOYSA-N 0.000 description 2
- VZCYOOQTPOCHFL-OWOJBTEDSA-N Fumaric acid Chemical compound OC(=O)\C=C\C(O)=O VZCYOOQTPOCHFL-OWOJBTEDSA-N 0.000 description 2
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerol Natural products OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 2
- IMNFDUFMRHMDMM-UHFFFAOYSA-N N-Heptane Chemical compound CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 description 2
- RDOXTESZEPMUJZ-UHFFFAOYSA-N anisole Chemical compound COC1=CC=CC=C1 RDOXTESZEPMUJZ-UHFFFAOYSA-N 0.000 description 2
- NMJJFJNHVMGPGM-UHFFFAOYSA-N butyl formate Chemical compound CCCCOC=O NMJJFJNHVMGPGM-UHFFFAOYSA-N 0.000 description 2
- YMFAWOSEDSLYSZ-UHFFFAOYSA-N carbon monoxide;cobalt Chemical group [Co].[Co].[Co].[Co].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-].[O+]#[C-] YMFAWOSEDSLYSZ-UHFFFAOYSA-N 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 2
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 description 2
- XBDQKXXYIPTUBI-UHFFFAOYSA-N dimethylselenoniopropionate Natural products CCC(O)=O XBDQKXXYIPTUBI-UHFFFAOYSA-N 0.000 description 2
- SNRUBQQJIBEYMU-UHFFFAOYSA-N dodecane Chemical compound CCCCCCCCCCCC SNRUBQQJIBEYMU-UHFFFAOYSA-N 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 235000011187 glycerol Nutrition 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- BDAGIHXWWSANSR-UHFFFAOYSA-N methanoic acid Natural products OC=O BDAGIHXWWSANSR-UHFFFAOYSA-N 0.000 description 2
- DNIAPMSPPWPWGF-UHFFFAOYSA-N monopropylene glycol Natural products CC(O)CO DNIAPMSPPWPWGF-UHFFFAOYSA-N 0.000 description 2
- YLYBTZIQSIBWLI-UHFFFAOYSA-N octyl acetate Chemical compound CCCCCCCCOC(C)=O YLYBTZIQSIBWLI-UHFFFAOYSA-N 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- AJCDFVKYMIUXCR-UHFFFAOYSA-N oxobarium;oxo(oxoferriooxy)iron Chemical compound [Ba]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O.O=[Fe]O[Fe]=O AJCDFVKYMIUXCR-UHFFFAOYSA-N 0.000 description 2
- 239000012071 phase Substances 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 238000010992 reflux Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- VZCYOOQTPOCHFL-UHFFFAOYSA-N trans-butenedioic acid Natural products OC(=O)C=CC(O)=O VZCYOOQTPOCHFL-UHFFFAOYSA-N 0.000 description 2
- RYHBNJHYFVUHQT-UHFFFAOYSA-N 1,4-Dioxane Chemical compound C1COCCO1 RYHBNJHYFVUHQT-UHFFFAOYSA-N 0.000 description 1
- HFZLSTDPRQSZCQ-UHFFFAOYSA-N 1-pyrrolidin-3-ylpyrrolidine Chemical compound C1CCCN1C1CNCC1 HFZLSTDPRQSZCQ-UHFFFAOYSA-N 0.000 description 1
- OSWFIVFLDKOXQC-UHFFFAOYSA-N 4-(3-methoxyphenyl)aniline Chemical compound COC1=CC=CC(C=2C=CC(N)=CC=2)=C1 OSWFIVFLDKOXQC-UHFFFAOYSA-N 0.000 description 1
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 description 1
- ZAFNJMIOTHYJRJ-UHFFFAOYSA-N Diisopropyl ether Chemical compound CC(C)OC(C)C ZAFNJMIOTHYJRJ-UHFFFAOYSA-N 0.000 description 1
- 125000000174 L-prolyl group Chemical group [H]N1C([H])([H])C([H])([H])C([H])([H])[C@@]1([H])C(*)=O 0.000 description 1
- OTGQIQQTPXJQRG-UHFFFAOYSA-N N-(octadecanoyl)ethanolamine Chemical compound CCCCCCCCCCCCCCCCCC(=O)NCCO OTGQIQQTPXJQRG-UHFFFAOYSA-N 0.000 description 1
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 1
- OFOBLEOULBTSOW-UHFFFAOYSA-N Propanedioic acid Natural products OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 description 1
- XBDQKXXYIPTUBI-UHFFFAOYSA-M Propionate Chemical compound CCC([O-])=O XBDQKXXYIPTUBI-UHFFFAOYSA-M 0.000 description 1
- HVUMOYIDDBPOLL-XWVZOOPGSA-N Sorbitan monostearate Chemical compound CCCCCCCCCCCCCCCCCC(=O)OC[C@@H](O)[C@H]1OC[C@H](O)[C@H]1O HVUMOYIDDBPOLL-XWVZOOPGSA-N 0.000 description 1
- KDYFGRWQOYBRFD-UHFFFAOYSA-N Succinic acid Natural products OC(=O)CCC(O)=O KDYFGRWQOYBRFD-UHFFFAOYSA-N 0.000 description 1
- 229930006000 Sucrose Natural products 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 235000011054 acetic acid Nutrition 0.000 description 1
- KXKVLQRXCPHEJC-UHFFFAOYSA-N acetic acid trimethyl ester Natural products COC(C)=O KXKVLQRXCPHEJC-UHFFFAOYSA-N 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 229940072049 amyl acetate Drugs 0.000 description 1
- PGMYKACGEOXYJE-UHFFFAOYSA-N anhydrous amyl acetate Natural products CCCCCOC(C)=O PGMYKACGEOXYJE-UHFFFAOYSA-N 0.000 description 1
- 239000003945 anionic surfactant Substances 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- KCXMKQUNVWSEMD-UHFFFAOYSA-N benzyl chloride Chemical compound ClCC1=CC=CC=C1 KCXMKQUNVWSEMD-UHFFFAOYSA-N 0.000 description 1
- 229920001400 block copolymer Polymers 0.000 description 1
- KDYFGRWQOYBRFD-NUQCWPJISA-N butanedioic acid Chemical compound O[14C](=O)CC[14C](O)=O KDYFGRWQOYBRFD-NUQCWPJISA-N 0.000 description 1
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000002915 carbonyl group Chemical group [*:2]C([*:1])=O 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 239000007806 chemical reaction intermediate Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- QYWXVBFLPIGNNL-UHFFFAOYSA-L disodium butanedioate 1-octylsulfonyloctane Chemical compound [Na+].[Na+].[O-]C(=O)CCC([O-])=O.CCCCCCCCS(=O)(=O)CCCCCCCC QYWXVBFLPIGNNL-UHFFFAOYSA-L 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 150000002170 ethers Chemical class 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 230000005294 ferromagnetic effect Effects 0.000 description 1
- 235000019253 formic acid Nutrition 0.000 description 1
- 239000001530 fumaric acid Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 150000008282 halocarbons Chemical class 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- MNWFXJYAOYHMED-UHFFFAOYSA-M heptanoate Chemical compound CCCCCCC([O-])=O MNWFXJYAOYHMED-UHFFFAOYSA-M 0.000 description 1
- 229920006158 high molecular weight polymer Polymers 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 239000002563 ionic surfactant Substances 0.000 description 1
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- VZCYOOQTPOCHFL-UPHRSURJSA-N maleic acid Chemical compound OC(=O)\C=C/C(O)=O VZCYOOQTPOCHFL-UPHRSURJSA-N 0.000 description 1
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- 229910052757 nitrogen Inorganic materials 0.000 description 1
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- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
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- TVMXDCGIABBOFY-UHFFFAOYSA-N octane Chemical compound CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 description 1
- 125000002347 octyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
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- 235000010989 polyoxyethylene sorbitan monostearate Nutrition 0.000 description 1
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Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は磁性材料として、特に高密度な磁気記録が可能
となる垂直磁気記録方式のための記録媒体（テープ、デ
ィスク、ドラム等）用の磁性粉として、有用な六方晶系
コバルト微粒子の新規な製造法に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention is a magnetic material, particularly for use in recording media (tapes, disks, drums, etc.) for perpendicular magnetic recording systems that enable high-density magnetic recording. This invention relates to a new method for producing hexagonal cobalt fine particles useful as magnetic powder.
（従来の技術〕
現行の長手方式と異なった究極的に高密度な磁気記録方
式として垂直方式が提唱され、その高い性能が試験的に
実証されている。この新方式を実用化するために新たな
特性をもつ塗付型の磁性粉、例えばバリウムフェライト
微粒子粉末が現在開発されつつある。(Prior technology) A perpendicular method has been proposed as the ultimate high-density magnetic recording method different from the current longitudinal method, and its high performance has been experimentally demonstrated.In order to put this new method into practical use, new Coating-type magnetic powders, such as barium ferrite fine particle powders, with such characteristics are currently being developed.
しかして、もし、該バリウムフェライト微粒子よりも高
い飽和磁化を有するコバルト微粒子を六方晶系の結晶格
子で且適当な粒径・分散と保磁力を示す磁性粉末として
製造できれば、これよりもずっと優れた垂直記録用素材
となることが予想される。However, if cobalt fine particles with higher saturation magnetization than the barium ferrite fine particles could be produced as magnetic powder with a hexagonal crystal lattice and appropriate particle size, dispersion, and coercive force, it would be possible to produce a much superior product. It is expected that it will be used as a material for perpendicular recording.
従来、高純度の金属状コバルトがコバルトカルボニルの
分解によって生成することは公知であり、またこの反応
を用いてコバルト磁性粉を製造する若干の方法も知られ
ている１例えば特公昭４〇−３４１５号は不活性溶媒中
で高分子重合体等の存在下にコバルトカルボニルを熱分
解する線状配列のコバルト微粒子の製法を、米国特許３
，２２８．８８１号はこれと類似の方法で分散状微粒子
の製法を、米国特許４，２５２，６７３号、米国特許４
，２５２．６７４はコロイド状コバルトの製法を、更に
特開昭５８−１３７２０２号は磁場を印加して熱分解す
る針状配列の微粒子粉末の製法を開示している。It has been known that high-purity metallic cobalt is produced by the decomposition of cobalt carbonyl, and some methods for producing cobalt magnetic powder using this reaction are also known. No. 3 describes a method for producing linearly arranged cobalt fine particles by thermally decomposing cobalt carbonyl in the presence of a high molecular weight polymer in an inert solvent.
, 228.881 discloses a method for producing dispersed fine particles using a method similar to this, and US Pat. No. 4,252,673 and US Pat.
, 252.674 discloses a method for producing colloidal cobalt, and JP-A-58-137202 discloses a method for producing fine particle powder having an acicular arrangement, which is thermally decomposed by applying a magnetic field.
しかしながら、これらの方法で得られるコバルト微粒子
は、結晶格子が六方晶系ではないという大きな問題があ
る。従って、そもそも、コバルト微粒子を垂直磁気記録
方式の磁性粉として用いようとする試みは従来全くなさ
れていないし、また垂直磁気記録方式の磁性粉として用
いられた該記録方式に好適な形状を有するコバルト微粒
子の例も全く見当らない。However, the cobalt fine particles obtained by these methods have a major problem in that the crystal lattice is not hexagonal. Therefore, in the first place, no attempt has been made to use cobalt fine particles as magnetic powder for perpendicular magnetic recording systems, and cobalt fine particles having a shape suitable for the recording system used as magnetic powder for perpendicular magnetic recording systems. I can't find any examples of this.
（発明が解決しようとする問題点〕
本発明が解決せんとする第１の主たる問題点は、コバル
トカルボニルから六方晶コバルト微粒子を如何にしてつ
くるかということである。(Problems to be Solved by the Invention) The first main problem to be solved by the present invention is how to produce hexagonal cobalt fine particles from cobalt carbonyl.
蓋し、コバルトの結晶格子には六方晶系と面心立方晶系
があるところ、本発明の用途とする垂直磁気記録方式用
の磁性粉としては、−軸結高磁気異方性を発現させるた
めに、前者の結晶系でなければならず、後者では役立た
ないからである。従来公知の前記製法により得られる六
方晶コバルト微粒子はすべて面心立方晶またはこれを主
とするものであり、本発明が意図する垂直磁気記録方式
の磁性粉としての用途には基本的に全く沿わないのであ
る。However, the crystal lattice of cobalt has a hexagonal system and a face-centered cubic system, and the magnetic powder for the perpendicular magnetic recording system used in the present invention is a cobalt crystal that exhibits -axial high magnetic anisotropy. Therefore, it must be the former crystal system, and the latter is useless. The hexagonal cobalt fine particles obtained by the conventionally known production method described above are all face-centered cubic or mainly face-centered cubic, and are basically completely unsuitable for use as magnetic powder in the perpendicular magnetic recording system intended by the present invention. There isn't.
本発明の企図する第２の問題点は、凝集し易い粒径サブ
ミクロン以下の粒子を如何にしてよい分散状態で得るか
という点にある。The second problem contemplated by the present invention is how to obtain particles with a particle diameter of submicron or less, which tend to aggregate, in a good dispersed state.
従来、公知の方法によるコバ用１粒子は、コロイド状に
高分散した磁性流体の微粒子以外では、針状、線状、環
状に配列したり、不規則に凝集または凝結しており、本
発明の用途には全く不適当だからである。Conventionally, particles for edges produced by a known method have been arranged in needles, lines, rings, or irregularly aggregated or coagulated, except for fine particles of magnetic fluid that are highly dispersed in a colloidal manner. This is because it is completely unsuitable for this purpose.
本発明の意図する第３の問題点は、如何にして高い飽和
磁化と適当な保磁力を微粒子粉末に保たせるかにある。The third problem addressed by the present invention is how to maintain high saturation magnetization and appropriate coercive force in the fine particles.
本発明者らは上記問題点を解決するため、榎々の溶剤や
界面活性剤存在下のコバルトカルボニルの分解反応を鋭
意研究した結果、低級カルボン酸エステルを溶剤として
特定の界面活性剤の存在下に反応させると六方晶コバル
トが生成すること、また意外なことに、この際溶媒が反
応に不活性ではな（コバルト微粒子の生成反応にある面
で関与しているらしいことを見出し、更に製造条件を検
討して本発明を完成するに到った。In order to solve the above problems, the present inventors conducted extensive research on the decomposition reaction of cobalt carbonyl in the presence of solvents and surfactants. It was discovered that hexagonal cobalt is produced when the reaction is carried out with After studying the following, we have completed the present invention.
以下、本発明の詳細な説明する。The present invention will be explained in detail below.
本発明は、コバルトカルボニルを炭素数４以下の低級カ
ルボン酸のアルキルエステルを溶剤として用いて非イオ
ン系界面活性剤の存在下に熱分解して六方晶コバルトｉ
粒子を分散状態で製造する方法である。The present invention produces hexagonal cobalt i by thermally decomposing cobalt carbonyl using an alkyl ester of a lower carboxylic acid having 4 or less carbon atoms as a solvent in the presence of a nonionic surfactant.
This is a method of producing particles in a dispersed state.
本発明においては、コバルトカルボニルの熱分解を低級
カルボン酸のアルキルエステル溶剤中で行うことが基本
的に重要である。In the present invention, it is fundamentally important that the thermal decomposition of cobalt carbonyl is carried out in an alkyl ester solvent of a lower carboxylic acid.
コバルトカルボニルの熱分解反応は、−酸化炭素を脱離
してコバルトを生成する一見単純な反応と見なされ易い
が、本発明者らが詳細に検討したところによると、実際
には一酸化炭素の脱離が進むにつれて種々のコバルトカ
ルボニル錯体またはクラスターを経由して、原子状コバ
ルトを生成するという工程を基本とするかなり複雑な反
応なのである。ジコバルトオクタカルボニルからは最初
に比較的低温側でテトラコバルトドデカカルボニルを生
成するが、これが引き続き不安定なりラスターを経て熱
分解する。The thermal decomposition reaction of cobalt carbonyl is likely to be considered at first glance to be a simple reaction in which carbon oxide is eliminated to produce cobalt, but according to a detailed study by the present inventors, it actually decomposes carbon monoxide. This is a fairly complex reaction based on the process of producing atomic cobalt through various cobalt carbonyl complexes or clusters as the separation progresses. Initially, tetracobalt dodecacarbonyl is produced from dicobalt octacarbonyl at a relatively low temperature, but this subsequently becomes unstable and undergoes thermal decomposition through rastering.
前記した公知の方法に於いては、いずれも最終的に面心
立方晶系のコバルトのみが生成するが、本発明のごとく
、低級カルボン酸エステル溶剤と非イオン系界面活性剤
が共存する特定の分解反応条件においては、当業者にと
って驚くべきことに、かつ全く予想外なことに、六方晶
系のコバルトのみが生成するのである。この理由ないし
詳細な反応機構は勿論現在のところ完全には明確ではな
いが、上記低級カルボン酸エステル溶剤と非イオン系界
面活性剤という二つの特定の構成要件の組み合わせか、
コバルト原子の配列が六方晶系の結晶格子を形成するよ
うに、本発明の目的にとってまことに都合良く、作用し
ているのであろうと推察される。In all of the above-mentioned known methods, only face-centered cubic cobalt is finally produced, but as in the present invention, a specific method in which a lower carboxylic acid ester solvent and a nonionic surfactant coexist is used. Under the decomposition reaction conditions, surprisingly and quite unexpectedly for those skilled in the art, only hexagonal cobalt is produced. The reason for this and the detailed reaction mechanism are of course not completely clear at present, but it may be a combination of two specific components, the lower carboxylic acid ester solvent and the nonionic surfactant.
It is inferred that the arrangement of cobalt atoms forms a hexagonal crystal lattice, which is very advantageous for the purpose of the present invention.
本発明において用いられる原料のコバルトカルボニルに
はＣｏｇ（Ｃｏ）ｓ、Ｇｏｏ（ＣＯ）＋ｉ 、ｃｏｈ＜
Ｃｏ）＋ｈ等の様な公知のカルボニル類の何れも使用可
能であり、特に、ジコバルトオクタカルボニルが最適で
ある。The cobalt carbonyl raw materials used in the present invention include Cog(Co)s, Goo(CO)+i, coh<
Any of the known carbonyls such as Co)+h can be used, and dicobalt octacarbonyl is particularly suitable.
本発明において溶剤として用いられる低級カルボン酸の
アルキルエステルは、炭素数４以下の有機カルボン酸、
例えば蟻酸、酢酸、プロピオン酸、酪酸、修酸、こはく
酸、マレイン酸やフマル酸のアルキルエステルであり、
メチル−、エチル−、プロとルー、ブチル−もしくはオ
クチル−エステル等が用いられる。なかでも、蟻酸ブチ
ル、酢酸メチル、酢酸エチル、酢酸ブチル、酢酸アミル
、酢酸オクチル、プロピオン酸ブチル等が望ましい、な
お、上記の外に他の不活性な溶剤を混合して使用するこ
ともできる。かかる不活性溶剤としてはヘプタン、オク
タン、ドデカン、シクロヘキサン、ベンゼン、トルエン
、キシレン、テトラリン等の様な炭化水素類；クロルベ
ンゼン、クロルトルエンの様なハロゲン化炭化水素類；
ジイソプロピルエーテル、ジオキサン、アニソールの様
なエーテル類が通常用いられる。かかる不活性溶剤を混
合する場合は、上記した低級カルボン酸エステルが少な
（とも１０％以上の組成となる様にすることが好ましい
。The alkyl ester of lower carboxylic acid used as a solvent in the present invention is an organic carboxylic acid having 4 or less carbon atoms,
For example, alkyl esters of formic acid, acetic acid, propionic acid, butyric acid, oxalic acid, succinic acid, maleic acid and fumaric acid,
Methyl, ethyl, pro-, butyl or octyl esters are used. Among them, butyl formate, methyl acetate, ethyl acetate, butyl acetate, amyl acetate, octyl acetate, butyl propionate and the like are preferred; however, other inert solvents may be mixed and used in addition to the above. Such inert solvents include hydrocarbons such as heptane, octane, dodecane, cyclohexane, benzene, toluene, xylene, tetralin, etc.; halogenated hydrocarbons such as chlorobenzene, chlorotoluene;
Ethers such as diisopropyl ether, dioxane, anisole are commonly used. When such an inert solvent is mixed, it is preferable that the above-mentioned lower carboxylic acid ester is contained in a small amount (at least 10%).
反応系にに仕込まれる原料のコバルトカルボニルの濃度
は通常溶剤量に対して１〜２０重量％の範囲であり、特
に２〜１０重量％が望ましい。The concentration of cobalt carbonyl as a raw material charged into the reaction system is usually in the range of 1 to 20% by weight, preferably 2 to 10% by weight, based on the amount of solvent.
本発明においては、反応は非イオン系界面活性剤の存在
下に行われる。In the present invention, the reaction is carried out in the presence of a nonionic surfactant.
ここで使用しうる非イオン系界面活性剤としてはとくに
制限はないが、例えばポリエチレングリコールラウリル
エーテル、ポリエチレングリコールパーフルオロアルキ
ルエーテル、ポリエチレングリコールノニルフェニルエ
ーテル、オキシエチレンオキシプロピレンブロックコポ
リマー等の様なエーテル型のもの；例えばグリセリンエ
ステルのポリオキシエチレンエーテル、ポリオキシエチ
レンソルビタンモノステアレート等の様なエーテルエス
テル型のもの；例えばポリエチレングリコールモノステ
アレート、フルオロアルキルエステル、ポリエチレング
リコールのグリセリンエステル、ソルビタンモノステア
レート、プロピレングリコールエステル、蔗糖エステル
等の様なエステル型のものと、例えばポリオキシエチレ
ンエチルアミン、ステアリン酸エタノールアミド、ポリ
オキシエチレンステアリン酸アミド、パーフルオロアル
キルアミンオキシド等の様な窒素含有型のもの等がある
。これらは、それぞれ単独でまたは混合した状態で使用
することが出来る。There are no particular restrictions on the nonionic surfactant that can be used here, but ether type surfactants such as polyethylene glycol lauryl ether, polyethylene glycol perfluoroalkyl ether, polyethylene glycol nonylphenyl ether, oxyethylene oxypropylene block copolymer, etc. Ether ester types such as polyoxyethylene ether of glycerin ester, polyoxyethylene sorbitan monostearate, etc.; such as polyethylene glycol monostearate, fluoroalkyl ester, glycerin ester of polyethylene glycol, sorbitan monostearate , ester type such as propylene glycol ester, sucrose ester, etc., and nitrogen-containing type such as polyoxyethylene ethylamine, stearic acid ethanolamide, polyoxyethylene stearic acid amide, perfluoroalkyl amine oxide, etc. There is. These can be used alone or in a mixed state.
なお、イオン系の界面活性剤は面心立方晶系のコバルト
が生成するため、本発明において用いることは出来ない
。Note that ionic surfactants cannot be used in the present invention because they produce face-centered cubic cobalt.
本発明において界面活性剤の使用量は特別の制限ハない
が、通常コバルトカルボニルに対しテ０゜０１〜５０重
量％であり、特に０．１〜２０重量％が望ましい。In the present invention, there is no particular restriction on the amount of surfactant used, but it is usually 0.01 to 50% by weight, preferably 0.1 to 20% by weight, based on cobalt carbonyl.
反応はジコバルトオクタカルボニルの場合加温程度で開
始して一酸化炭素を一節放出し、１００℃以下でまずテ
トラコバルトドデカカルボニルを生成する。しかしなが
ら、−酸化炭素を完全に脱離して六方晶コバルトを生成
するには１００℃を越える高い温度が望ましい、−船釣
には実質的に５０℃〜２００℃の温度範囲が選択される
が、特に反応の最終段階では、１００℃〜２００℃の範
囲の温度が使用される。勿論２００℃を越える高温も使
用出来るが通常このような高温で反応させることは必要
ない、なお、反応を低温便と高温側にわけて一酸化炭素
の発生量を適当な範囲に制御しながら反応を進行させる
ことも好ましい態様である。In the case of dicobalt octacarbonyl, the reaction is started by heating, carbon monoxide is released once, and tetracobalt dodecacarbonyl is first produced at 100° C. or lower. However, - a high temperature of over 100°C is desirable to completely eliminate carbon oxide and produce hexagonal cobalt; - a temperature range of 50°C to 200°C is practically selected for boat fishing; Temperatures in the range 100°C to 200°C are used, especially in the final stages of the reaction. Of course, high temperatures exceeding 200°C can be used, but normally it is not necessary to carry out the reaction at such high temperatures.The reaction can be divided into low-temperature and high-temperature stages, and the reaction can be carried out while controlling the amount of carbon monoxide generated within an appropriate range. It is also a preferred embodiment to allow the process to proceed.
反応圧力は通常大気圧程度が好ましい、しかして、コバ
ルトカルボニルの空気による酸化を避けるために反応の
開始までは反応系内を一酸化炭素、窒素等の非酸化性気
体の雰囲気に保つとともに、反応が開始した以後は、反
応によって発生する一酸化炭素をできるだけ速やかに反
応系外に排出することが望ましい。The reaction pressure is usually about atmospheric pressure.However, in order to avoid oxidation of cobalt carbonyl by air, the reaction system is kept in an atmosphere of non-oxidizing gases such as carbon monoxide and nitrogen until the start of the reaction. After the reaction has started, it is desirable to discharge the carbon monoxide generated by the reaction out of the reaction system as quickly as possible.
本発明における反応は、原料コバルトカルボニル、反応
中間体および最終反応生成物たるコバルト微粒子が固体
が液相中に懸濁した状態で反応が進行する固−液不均−
相の反応であり、従って反応をスムースに進行せしめる
為には、通常の固−液不均−相反応に対する化学工学的
配慮を払い特に反応系内を充分効果的に攪拌または流動
させせ固体粒子を充分浮遊させるとともに固−液間の相
対速度を充分太き（することが好ましい。The reaction in the present invention is a solid-liquid heterogeneous reaction in which the raw material cobalt carbonyl, the reaction intermediate, and the cobalt fine particles as the final reaction product proceed in a state where the solid is suspended in a liquid phase.
This is a phase reaction, and therefore, in order for the reaction to proceed smoothly, consideration must be given to chemical engineering compared to ordinary solid-liquid heterogeneous phase reactions, and in particular, the reaction system must be sufficiently effectively stirred or fluidized, and the solid particles must be sufficiently stirred or fluidized. It is preferable to sufficiently suspend the solid-liquid relative velocity.
反応時間は原料のコバルトカルボニル、溶剤、および界
面活性剤の種類と使用量や反応温度等の反応条件によっ
て異なりうるが、通常１時間〜１０時間程度の範囲が選
択される。なお、反応はこの範囲で適当な時間を選択さ
せることにより実賞的に１００％の収率で六方晶コバル
ト微粒子を得ることが出来る。もちろん、本発明は回分
式または連続式のいずれの方式によっても実施すること
が出来る０反応により副生じた一酸化炭素と反応に用い
た溶剤と界面活性剤は回収して再使用することが出来る
。The reaction time may vary depending on the types and amounts of the cobalt carbonyl raw materials, the solvent, and the surfactant, and the reaction conditions such as the reaction temperature, but is usually selected within the range of about 1 hour to 10 hours. By selecting an appropriate reaction time within this range, it is possible to obtain hexagonal cobalt fine particles with a practically 100% yield. Of course, the present invention can be carried out either batchwise or continuously. The carbon monoxide produced by the reaction and the solvent and surfactant used in the reaction can be recovered and reused. .
本発明において、反応生成物として得られたコバルト微
粒子は溶剤から分離され、そのままでまたは慣用の方法
で洗浄、徐酸化乾燥等の必要な工程を経て高純度のコバ
ルト微粒子となる。この粉末は高純度のコバルト微粒子
から成り、結晶性のよい六方晶型格子を示すため、垂直
磁気記録材料用の磁性微粒子粉末として好適に使用可能
なものである。なお、反応条件によって多少の差は生じ
うるが、本発明により得られるコバルト微粒子は粒径ｏ
、ｏｏｓ〜０．２μｍ１特に０．０１〜０．０５μ−の
範囲で比較的球状のものであり、しかも、従来技術によ
るような針状、線状、環状に配列したり、不規則に凝結
または凝集することは実賞的に見られず、よ（均一に分
散しているものである。In the present invention, the cobalt fine particles obtained as a reaction product are separated from the solvent and become highly pure cobalt fine particles as they are or through necessary steps such as washing and slow oxidation drying in a conventional manner. This powder is composed of high-purity cobalt fine particles and exhibits a hexagonal lattice with good crystallinity, so it can be suitably used as a magnetic fine particle powder for perpendicular magnetic recording materials. Although some differences may occur depending on the reaction conditions, the cobalt fine particles obtained by the present invention have a particle size o
, oos ~ 0.2 μm1, especially in the range of 0.01 ~ 0.05 μm, and is relatively spherical, and is not arranged in an acicular, linear, or ring shape as in the prior art, or irregularly condensed or There is no visible agglomeration; it is uniformly dispersed.
本発明により得られるコバルト微粒子は、強磁性体であ
り、通常飽和磁化１０１００ｅ／ｇ以上で保磁力１００
０ ＠以上の有用な磁性微粒子粉末となる。The cobalt fine particles obtained by the present invention are ferromagnetic, and usually have a saturation magnetization of 10,100 e/g or more and a coercive force of 100.
It becomes a useful magnetic fine particle powder of 0 @ or more.
（実施例〕
以下、実施例と比較例によって本発明を具体的に説明す
る。(Examples) Hereinafter, the present invention will be specifically explained using Examples and Comparative Examples.
実施例１
ジコバルトオクタカルボニル２ｇ１ポリエチレングリコ
ールモノステアレー）０．２ｇと酢酸ブチル５０＋ｓｌ
を２００ｍ１円筒型フラスコに窒素雲囲気下に仕込んだ
、攪拌しながら、５０℃で０．５時間次いで１２５℃で
還流させながら１時間加熱した。この関に発生した一酸
化炭素を還流冷却器を経て排出し計量したところ、仕込
み原料に含有されていた一酸化炭素に相当する量であっ
た。冷却後に内容物を取り出し、上澄液を傾斜分離した
。残渣をメタノールで洗浄・傾斜分離してから乾燥する
と黒色コバルト微粒子０．７６ｇが得られた。Example 1 2g dicobalt octacarbonyl 0.2g polyethylene glycol monostearate) and 50+sl butyl acetate
The mixture was placed in a 200 ml cylindrical flask under a nitrogen atmosphere and heated at 50° C. for 0.5 hour with stirring and then at 125° C. for 1 hour under reflux. When the carbon monoxide generated at this point was discharged through a reflux condenser and weighed, the amount was equivalent to the carbon monoxide contained in the raw materials. After cooling, the contents were taken out and the supernatant liquid was decanted. The residue was washed with methanol, decanted and then dried to obtain 0.76 g of black cobalt fine particles.
このコバルト微粒子はＸ線回折分析によると結晶性のよ
い六方晶系であり、面心立方系は含まれていないことが
分かうた。を子顕微鏡によると粒径０．０１〜０．０３
μ−の球形に近い粒子が、比較的よく分散していた。ま
た振動試料型磁力計により５０、まで磁化した飽和磁化
は１２６ｅｍｎ／ｇ、保磁力は２４８０ｅの磁性粉であ
った。According to X-ray diffraction analysis, the cobalt fine particles were found to have a hexagonal system with good crystallinity, and did not contain face-centered cubic systems. According to the child microscope, the particle size is 0.01~0.03
Particles close to spherical shape of μ− were relatively well dispersed. Further, the magnetic powder was magnetized to 50 by a vibrating sample magnetometer, had a saturation magnetization of 126 emn/g, and a coercive force of 2480 e.
比較例１
酢酸ブチルの代わりにトルエンを用いた以外は実施例１
と同様にして２時間反応を行った。器壁に鏡面を形成し
ながら分解して一酸化炭素が定量的に発生し沈澱物と共
に磁性流体が得られた。該沈澱物および該磁性流体をド
ラ゛イアツブして得たコバルト粒子はいずれも面心立方
晶であった。Comparative Example 1 Example 1 except that toluene was used instead of butyl acetate
The reaction was carried out in the same manner as above for 2 hours. It decomposed while forming a mirror surface on the vessel wall, and carbon monoxide was quantitatively generated, and magnetic fluid was obtained along with the precipitate. The cobalt particles obtained by drying the precipitate and the magnetic fluid both had face-centered cubic crystals.
比較例２
ポリエチレングリコールモノステアレートの代わりに陰
イオン界面活性剤のジオクチルスルホンこはく酸ナトリ
ウムを用いた以外は実施例１と同様に反応を行った。得
られたコバルト粒子は面心立方晶であった。Comparative Example 2 A reaction was carried out in the same manner as in Example 1, except that an anionic surfactant, sodium dioctyl sulfone succinate, was used instead of polyethylene glycol monostearate. The obtained cobalt particles were face-centered cubic crystals.
実施例２
ポリエチレングリコールモノステアレートの代わりにポ
リエチレングリコールモノラウリルエーテルを用いて実
施例１と同様の実験を実施した。Example 2 An experiment similar to Example 1 was conducted using polyethylene glycol monolauryl ether instead of polyethylene glycol monostearate.
−酸化炭素が定量的に回収され、黒色コバルト微粉末０
．６５ｇが得られた。この微粒子は六方晶系であり、粒
径は主として０．０２〜０．０３μ薄であり、飽和磁化
は１０１０２ｅ／ｇ、保磁力は１８８０ｅの磁性粉であ
った。- Quantitative recovery of carbon oxide and zero fine black cobalt powder
．． 65g was obtained. This fine particle was a magnetic powder having a hexagonal crystal system, a particle size mainly 0.02 to 0.03 μm thin, a saturation magnetization of 10102 e/g, and a coercive force of 1880 e.
比較例３
酢酸ブチルの代わりにトルエンを用いて実施例２と同様
の実験を行ったが得られたコバルト粒子は面心立方晶で
あった。Comparative Example 3 An experiment similar to Example 2 was conducted using toluene instead of butyl acetate, but the cobalt particles obtained were face-centered cubic crystals.
（発明の効果）
本発明の方法によれば、コバルトカルボニルから粒径ｏ
、ｏｏｓ〜０．２μ鴎の六方晶コバルト微粒子を好収率
で製造することが初めて可能となる。これは磁性材料と
して、特に垂直磁気記録用社性粉として必要な基本的性
賀を具備するので、これに対し有益な用途を開くもので
ある。(Effect of the invention) According to the method of the invention, cobalt carbonyl can be
, it becomes possible for the first time to produce hexagonal cobalt fine particles of 0.000 to 0.2 μg in a good yield. This opens up useful applications for it as a magnetic material, in particular as a magnetic powder for perpendicular magnetic recording, since it possesses the necessary basic properties.
Claims (3)
ルトカルボニルを炭素数４以下の低級カルボン酸のアル
キルエステルを溶剤として用いて非イオン系界面活性剤
の存在下に熱分解することを特徴とする六方晶コバルト
微粒子の製造法。(1) A method for producing cobalt fine particles, characterized by thermally decomposing cobalt carbonyl in the presence of a nonionic surfactant using an alkyl ester of a lower carboxylic acid having 4 or less carbon atoms as a solvent. A method for producing hexagonal cobalt fine particles.
〜０．２μｍの六方晶コバルト微粒子である特許請求の
範囲第１項記載の方法。(2) The obtained hexagonal cobalt fine particles have a particle size of 0.005
The method according to claim 1, wherein the hexagonal cobalt fine particles have a diameter of 0.2 μm.
体用磁性材料として好適に使用しうる特許請求の範囲第
１項もしくは第２項に記載の方法。(3) The method according to claim 1 or 2, in which the obtained hexagonal cobalt fine particles can be suitably used as a magnetic material for perpendicular magnetic recording media.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14604986A JPS634007A (en) | 1986-06-24 | 1986-06-24 | Production of fine hexagonal cobalt particles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14604986A JPS634007A (en) | 1986-06-24 | 1986-06-24 | Production of fine hexagonal cobalt particles |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS634007A true JPS634007A (en) | 1988-01-09 |
Family
ID=15398940
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14604986A Pending JPS634007A (en) | 1986-06-24 | 1986-06-24 | Production of fine hexagonal cobalt particles |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS634007A (en) |
-
1986
- 1986-06-24 JP JP14604986A patent/JPS634007A/en active Pending
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