JPS63310730A - Hexagonal ferrite magnetic powder and its production - Google Patents
Hexagonal ferrite magnetic powder and its productionInfo
- Publication number
- JPS63310730A JPS63310730A JP14520687A JP14520687A JPS63310730A JP S63310730 A JPS63310730 A JP S63310730A JP 14520687 A JP14520687 A JP 14520687A JP 14520687 A JP14520687 A JP 14520687A JP S63310730 A JPS63310730 A JP S63310730A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic powder
- elements
- precipitate
- ferrite magnetic
- hexagonal ferrite
- 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.)
- Granted
Links
- 239000006247 magnetic powder Substances 0.000 title claims abstract description 32
- 229910000859 α-Fe Inorganic materials 0.000 title claims abstract description 19
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 24
- 239000002244 precipitate Substances 0.000 claims abstract description 24
- 229910001854 alkali hydroxide Inorganic materials 0.000 claims abstract description 18
- 150000008044 alkali metal hydroxides Chemical class 0.000 claims abstract description 18
- 239000000203 mixture Substances 0.000 claims abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 13
- 230000004907 flux Effects 0.000 claims abstract description 10
- 239000007858 starting material Substances 0.000 claims abstract description 10
- 229910052742 iron Inorganic materials 0.000 claims abstract description 9
- 239000002002 slurry Substances 0.000 claims abstract description 8
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 7
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 7
- 229910052725 zinc Inorganic materials 0.000 claims abstract description 7
- 229910052802 copper Inorganic materials 0.000 claims abstract description 6
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 6
- 229910052718 tin Inorganic materials 0.000 claims abstract description 6
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 6
- 229910052721 tungsten Inorganic materials 0.000 claims abstract description 6
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 5
- 229910052726 zirconium Inorganic materials 0.000 claims abstract description 5
- 238000000034 method Methods 0.000 claims description 15
- AJCDFVKYMIUXCR-UHFFFAOYSA-N oxobarium;oxo(oxoferriooxy)iron Chemical group [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 claims description 15
- 229910052788 barium Inorganic materials 0.000 claims description 10
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 claims description 6
- 239000000047 product Substances 0.000 claims description 6
- 229910052791 calcium Inorganic materials 0.000 claims description 4
- 150000001875 compounds Chemical class 0.000 claims description 4
- 238000010304 firing Methods 0.000 claims description 4
- 229910052712 strontium Inorganic materials 0.000 claims description 4
- 230000032683 aging Effects 0.000 claims description 3
- 229910052745 lead Inorganic materials 0.000 claims description 3
- 229910052749 magnesium Inorganic materials 0.000 claims description 3
- 238000005406 washing Methods 0.000 claims description 3
- 239000011259 mixed solution Substances 0.000 claims 1
- 239000000463 material Substances 0.000 abstract 1
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 12
- 239000007864 aqueous solution Substances 0.000 description 7
- 239000002245 particle Substances 0.000 description 7
- VCJMYUPGQJHHFU-UHFFFAOYSA-N iron(3+);trinitrate Chemical compound [Fe+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O VCJMYUPGQJHHFU-UHFFFAOYSA-N 0.000 description 6
- 238000002156 mixing Methods 0.000 description 6
- -1 Pl) Inorganic materials 0.000 description 4
- 238000000975 co-precipitation Methods 0.000 description 4
- 235000011121 sodium hydroxide Nutrition 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- 238000006467 substitution reaction Methods 0.000 description 4
- 239000010936 titanium Substances 0.000 description 4
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- RQPZNWPYLFFXCP-UHFFFAOYSA-L barium dihydroxide Chemical compound [OH-].[OH-].[Ba+2] RQPZNWPYLFFXCP-UHFFFAOYSA-L 0.000 description 3
- 229910001863 barium hydroxide Inorganic materials 0.000 description 3
- 239000011575 calcium Substances 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 238000002425 crystallisation Methods 0.000 description 3
- 238000001027 hydrothermal synthesis Methods 0.000 description 3
- 230000005415 magnetization Effects 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- WDIHJSXYQDMJHN-UHFFFAOYSA-L barium chloride Chemical compound [Cl-].[Cl-].[Ba+2] WDIHJSXYQDMJHN-UHFFFAOYSA-L 0.000 description 2
- 229910001626 barium chloride Inorganic materials 0.000 description 2
- 150000001553 barium compounds Chemical class 0.000 description 2
- IWOUKMZUPDVPGQ-UHFFFAOYSA-N barium nitrate Chemical compound [Ba+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O IWOUKMZUPDVPGQ-UHFFFAOYSA-N 0.000 description 2
- ZCCIPPOKBCJFDN-UHFFFAOYSA-N calcium nitrate Chemical compound [Ca+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ZCCIPPOKBCJFDN-UHFFFAOYSA-N 0.000 description 2
- 238000004140 cleaning Methods 0.000 description 2
- UFMZWBIQTDUYBN-UHFFFAOYSA-N cobalt dinitrate Chemical compound [Co+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O UFMZWBIQTDUYBN-UHFFFAOYSA-N 0.000 description 2
- 229910001981 cobalt nitrate Inorganic materials 0.000 description 2
- 230000008025 crystallization Effects 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000000634 powder X-ray diffraction Methods 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- PUZPDOWCWNUUKD-UHFFFAOYSA-M sodium fluoride Chemical compound [F-].[Na+] PUZPDOWCWNUUKD-UHFFFAOYSA-M 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- XJDNKRIXUMDJCW-UHFFFAOYSA-J titanium tetrachloride Chemical compound Cl[Ti](Cl)(Cl)Cl XJDNKRIXUMDJCW-UHFFFAOYSA-J 0.000 description 2
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 229910020517 Co—Ti Inorganic materials 0.000 description 1
- 229910000608 Fe(NO3)3.9H2O Inorganic materials 0.000 description 1
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 229910000805 Pig iron Inorganic materials 0.000 description 1
- 239000004115 Sodium Silicate Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000001110 calcium chloride Substances 0.000 description 1
- 229910001628 calcium chloride Inorganic materials 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- RCJVRSBWZCNNQT-UHFFFAOYSA-N dichloridooxygen Chemical compound ClOCl RCJVRSBWZCNNQT-UHFFFAOYSA-N 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 229910052595 hematite Inorganic materials 0.000 description 1
- 239000011019 hematite Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 150000002506 iron compounds Chemical class 0.000 description 1
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 1
- LIKBJVNGSGBSGK-UHFFFAOYSA-N iron(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Fe+3].[Fe+3] LIKBJVNGSGBSGK-UHFFFAOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000001103 potassium chloride Substances 0.000 description 1
- 235000011164 potassium chloride Nutrition 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 230000002250 progressing effect Effects 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- RMAQACBXLXPBSY-UHFFFAOYSA-N silicic acid Chemical compound O[Si](O)(O)O RMAQACBXLXPBSY-UHFFFAOYSA-N 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 239000011775 sodium fluoride Substances 0.000 description 1
- 235000013024 sodium fluoride Nutrition 0.000 description 1
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 1
- 229910052911 sodium silicate Inorganic materials 0.000 description 1
- 229910001631 strontium chloride Inorganic materials 0.000 description 1
- AHBGXTDRMVNFER-UHFFFAOYSA-L strontium dichloride Chemical compound [Cl-].[Cl-].[Sr+2] AHBGXTDRMVNFER-UHFFFAOYSA-L 0.000 description 1
- 239000011135 tin Substances 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Landscapes
- Compounds Of Iron (AREA)
- Hard Magnetic Materials (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、六方晶フェライト磁性粉およびその製造方法
に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to hexagonal ferrite magnetic powder and a method for producing the same.
さらに詳しくは、本発明は高密度記録用の磁気記録媒体
に用いるのに適した、比表面積が２０〜７０ｒ／／（］
、保磁力が２００〜１５０００ｅであり、保磁力の温度
変化が小さい六方晶フェライト磁性粉およびその製造方
法に関するものである。More specifically, the present invention has a specific surface area of 20 to 70 r//(] suitable for use in a magnetic recording medium for high-density recording.
, relates to a hexagonal ferrite magnetic powder having a coercive force of 200 to 15,000e and a small temperature change in coercive force, and a method for producing the same.
近年、磁気記録の高密度化の要求に伴い、六方晶フェラ
イト磁性粉を磁気記録媒体として用いる垂直磁気記録方
式の開発が進められている。In recent years, with the demand for higher density magnetic recording, development of perpendicular magnetic recording systems using hexagonal ferrite magnetic powder as a magnetic recording medium has been progressing.
垂直磁気記録方式に用いられる六方晶フェライト磁性粉
としては、保磁力が適当な値（２００〜１５０００ｅ）
で、飽和磁化ができるだけ高く、保磁力の温度変化が小
さいものが望まれている。The hexagonal ferrite magnetic powder used in the perpendicular magnetic recording system has an appropriate coercive force (200 to 15,000e).
Therefore, it is desired that the saturation magnetization is as high as possible and that the temperature change in coercive force is small.
（従来の技術およびその問題点）
従来、六方晶フェライト磁性粉の製造方法としては、例
えば共沈法、ガラス結晶化法、水熱合成法専科々の方法
が知られており、ガラス結晶化法については特公昭６０
−１５５７４号公報、水熱合成法については、例えば特
開昭５９−１７５７０７号公報、特公昭６０−１２９７
３号公報、特公昭６０−１５５７６号公報、特開昭６０
−１３７００２号公報等で提案されている。(Prior art and its problems) Conventionally, methods for producing hexagonal ferrite magnetic powder include coprecipitation, glass crystallization, and hydrothermal synthesis. About 1986 special public service
Regarding the hydrothermal synthesis method, see Japanese Patent Application Laid-open No. 59-175707, Japanese Patent Publication No. 60-1297.
Publication No. 3, Japanese Patent Publication No. 15576/1983, Japanese Patent Application Publication No. 1983
It has been proposed in Publication No.-137002 and the like.
前記方法により得られる六方晶フェライト磁性粉は、磁
気記録媒体として使用するために保磁力をさげる目的で
Ｃｏ、Ｎｉ、ｃｕ、Ｚｎ等の２価元素と、Ｔｉ、Ｓｎ、
Ｚｒ、等の４価元素またはＮｂ、Ｖ、Ｍｏ、Ｗ等の５価
元素との組合わせで、鉄原子を置換している。この場合
、置換される鉄原子と同数の元素で置換しており、しか
も置換元素の価数の合計が置換される鉄原子のそれと等
しくなるように置換して電荷を補償している０例えば、
鉄原子をＣ。The hexagonal ferrite magnetic powder obtained by the above method contains divalent elements such as Co, Ni, cu, and Zn, and Ti, Sn,
Iron atoms are replaced by a combination with a tetravalent element such as Zr or a pentavalent element such as Nb, V, Mo, W, etc. In this case, the substitution is made with the same number of elements as the iron atoms to be replaced, and the charges are compensated by substitution so that the total valence of the replacing elements is equal to that of the iron atoms to be replaced. For example,
C for iron atom.
−Ｔｉの２価と４価の組合わせで置換する場合、置換さ
れる鉄原子と同数の原子数でＣｏ−Ｔｉを加え、その割
合をモル比で１＝１として平均して原子価数が３となる
ように置換している。When replacing with a combination of divalent and tetravalent -Ti, add Co-Ti in the same number as the iron atoms to be replaced, set the molar ratio of 1=1, and average the valence number. It is replaced so that it becomes 3.
しかしながら、前記従来法における置換方法によれば、
保磁力の制御はできるものの、温度による保磁力の変化
が大きく、媒体化した場合に記録再生特性が使用時にお
ける周囲温度の変化に伴い大幅に変動することになり、
実用上支障を生じるという問題があった。However, according to the conventional replacement method,
Although it is possible to control the coercive force, the coercive force varies greatly with temperature, and when used as a medium, the recording and reproducing characteristics will fluctuate significantly as the ambient temperature changes during use.
There was a problem in that it caused problems in practical use.
（発明の目的）
本発明の目的は、前記問題点を解決し、微粒子で比表面
積が２０〜７０イ／ｇ、保磁力が２００〜１５０００ｃ
であり、保磁力の温度変化が小さい高密度記録用の磁気
記録媒体に用いるのに適した六方晶フェライト磁性粉お
よびその製造方法を提供することにある。(Objective of the Invention) The object of the present invention is to solve the above-mentioned problems, and to obtain fine particles with a specific surface area of 20 to 70 I/g and a coercive force of 200 to 15000 C.
The object of the present invention is to provide a hexagonal ferrite magnetic powder suitable for use in a magnetic recording medium for high-density recording in which the coercive force changes little with temperature, and a method for producing the same.
（問題点を解決するための手段）
本発明者等は、鋭意検討の結果、六方晶フェライト磁性
粉の鉄原子の一部を他の元素で置換するに当′す、置換
される鉄原子数よりも少ない原子数で置換して結晶格子
中の鉄原子の位置を一部空格子とし、しかも鉄の置換位
置の平均原子価を３未満として電荷を補償しないことに
より、保磁力の温度変化が小さくなることを見出した。(Means for Solving the Problems) As a result of intensive studies, the present inventors determined that when some of the iron atoms in hexagonal ferrite magnetic powder are replaced with other elements, the number of iron atoms to be replaced is By substituting with a smaller number of atoms to make some of the iron atom positions in the crystal lattice vacant, and by setting the average valence of the iron substitution positions to less than 3 and not compensating for charge, temperature changes in coercive force can be suppressed. I found out that it gets smaller.
すなわち、本発明は、一般式
％式％
（ただし、ＡはＢａ、Ｓｒ、Ｐｌ）、Ｃａ、Ｍｇからな
る群から選ばれる一種以上の元素を示し、ＭはＣｏ、Ｎ
ｉ。That is, the present invention represents one or more elements selected from the group consisting of the general formula % (where A is Ba, Sr, Pl), Ca, and Mg, and M is Co, N
i.
Ｃｕ、Ｚｎ等の２価元素、Ｔｉ、Ｓｎ、Ｚｒ、等の４価
元素およびＮｂ、Ｖ、Ｍｏ、Ｗ等の５価元素からなる群
から選ばれる一種以上の元素または元素の組合わせを示
し、０．１ ＜ ｘ ＜ ２５．０．１＜ｙ＜ｘ、ｚ＝
（３ｘ−ｍｙ）／２、かつＯ＜ｚであり、ｍはＭの平均
原子価を表す、）で表される六方晶フェライト磁性粉お
よびその製造方法に関する。Indicates one or more elements or a combination of elements selected from the group consisting of divalent elements such as Cu and Zn, tetravalent elements such as Ti, Sn, Zr, and pentavalent elements such as Nb, V, Mo, and W. ,0.1<x<25.0.1<y<x,z=
The present invention relates to a hexagonal ferrite magnetic powder represented by (3x-my)/2 and O<z, where m represents the average valence of M, and a method for producing the same.
本発明の一般式 ＡＯ−Ｆｅ１２−ｘＭｙＯ１８−７に
おいて、Ａとしては、Ｂａ、Ｓｒ、Ｐｂ、Ｃａ、Ｍｇか
らなる群から選ばれる一種以上の元素が用いられる９Ｍ
としては、Ｃｏ、Ｎｉ、Ｃｕ、Ｚｎ等の２価元素、Ｔｉ
、Ｓｎ、Ｚｒ、等の４価元素およびＮｌｌ、Ｖ、Ｍｏ、
Ｗ等の５価元素からなる群から選ばれる一種以上の元素
または元素の組合わせが用いられる。In the general formula AO-Fe12-xMyO18-7 of the present invention, A is 9M in which one or more elements selected from the group consisting of Ba, Sr, Pb, Ca, and Mg are used.
Examples include divalent elements such as Co, Ni, Cu, and Zn, Ti
, Sn, Zr, etc. and Nll, V, Mo,
One or more elements or a combination of elements selected from the group consisting of pentavalent elements such as W are used.
置換される鉄原子のｍｘは、０．１＜ｘ＜１５である。mx of the iron atom to be substituted is 0.1<x<15.
Ｘがこの範囲を外れると保磁力が高すぎたり、磁化容易
軸がＣ軸からずれてくるので好ましくない、置換元素Ｍ
の量ｙは０．１ ＜ ｙ ＜ ｘであり、Ｍの平均原子
価ｍが、Ｚ＝ （３ｘ−ｍｙ）／２＞０となるように置
換元素の組合わせを選ぶ、置換元素の量および組合わせ
を前記範囲とすることで、置換される鉄原子数よりも置
換原子数が少なくなり、結晶格子中の鉄原子の位置が一
部空格子となリ、しかも鉄の置換位置の平均原子価が３
未満となり電荷が補償されないことにより、保磁力の温
度変化を小さくすることができる。If X is outside this range, the coercive force will be too high or the axis of easy magnetization will shift from the C axis, which is undesirable.
The amount y of substituting elements is 0.1 < y < x, and the combination of substituting elements is selected so that the average valence m of M is Z = (3x-my)/2>0. By setting the combination within the above range, the number of substituted atoms is smaller than the number of iron atoms to be substituted, some of the positions of iron atoms in the crystal lattice become vacant, and moreover, the average atomic number of iron substitution positions is reduced. Value is 3
Since the charge is not compensated for, the change in coercive force due to temperature can be reduced.
上記六方晶フェライト磁性粉の製造方法としては、共沈
法、ガラス結晶化法、水熱合成法等が挙げられるが、粒
子形状、コストの点から共沈法が好ましい。Methods for producing the hexagonal ferrite magnetic powder include a coprecipitation method, a glass crystallization method, a hydrothermal synthesis method, etc., but the coprecipitation method is preferable from the viewpoint of particle shape and cost.
以下、共沈法によりバリウムフェライト磁性粉を製造す
る方法を述べる。Hereinafter, a method for producing barium ferrite magnetic powder using a coprecipitation method will be described.
本発明においては、出発原料として、バリウム１グラム
原子に対して、鉄１２−ｘグラム原子、Ｍがｙグラム原
子の割合のそれぞれの元素の化合物を用い、該出発原料
を水に溶解し、これに混合後の溶液中の水酸化アルカリ
濃度が３モル／ρ以上となるように水酸化アルカリを加
えて沈澱物を生成させ、該沈澱物を含むスラリを５０〜
８０℃で熟成した後、生成した沈澱物に融剤を混合し、
混合物を７００〜９５０”Ｃで焼成し、得られた焼成物
を洗浄することにより、六方晶バリウムフェライト磁性
粉が得られる。In the present invention, a compound of each element is used as a starting material in a ratio of 12-x gram atom of iron and y gram atom of M to 1 gram atom of barium, and the starting material is dissolved in water. Add alkali hydroxide to form a precipitate so that the alkali hydroxide concentration in the solution after mixing is 3 mol/ρ or more, and add the slurry containing the precipitate to 50 to
After aging at 80°C, a fluxing agent is mixed with the resulting precipitate,
Hexagonal barium ferrite magnetic powder is obtained by firing the mixture at 700 to 950''C and washing the resulting fired product.
本発明においては、まず出発原料であるバリウム、銑お
よびＭのそれぞれの化合物分水に溶解し、これに水酸化
アルカリを加えて沈澱物を生成させる。In the present invention, the starting materials barium, pig iron, and M are first dissolved in water, and alkali hydroxide is added thereto to form a precipitate.
バリウム化合物としては、硝酸バリウム、塩化バリウム
、水酸化バリウム等が用いられる。バリウムの使用量は
、バリウム濃度が０．０３〜０．５０モル／１の範囲に
なるようにするのが六方晶の結晶性のよい粒子を得るう
えで望ましい。As the barium compound, barium nitrate, barium chloride, barium hydroxide, etc. are used. In order to obtain hexagonal particles with good crystallinity, it is desirable to use the amount of barium such that the barium concentration is in the range of 0.03 to 0.50 mol/1.
鉄化合物としては、硝酸第二鉄、塩化第二鉄等が用いら
れる。As the iron compound, ferric nitrate, ferric chloride, etc. are used.
Ｍの化合物としては、その塩化物、鎖酸塩、オキシクロ
ライド等の水に可溶性のものが用いられる。As the compound M, those soluble in water such as its chloride, chain acid salt, oxychloride, etc. are used.
水酸化アルカリとしては、水酸化ナトリウム、水酸化カ
リウム等が用いられる。水酸化アルカリの使用量は水酸
化アルカリを混合した後の溶液中の水酸化アルカリ濃度
が３モル／！Ｊ以上となる量が必要であり、４〜８モル
／ｌの範囲が好ましい。As the alkali hydroxide, sodium hydroxide, potassium hydroxide, etc. are used. The amount of alkali hydroxide used is that the alkali hydroxide concentration in the solution after mixing the alkali hydroxide is 3 mol/! The amount is required to be J or more, and is preferably in the range of 4 to 8 mol/l.
水酸化アルカリの量が少なすぎると粒子が大きくなった
り、粒度分布が広くなったり、またへマタイトが生成す
る。また水酸化アルカリを過度に多くするのは経済的で
ない。If the amount of alkali hydroxide is too small, the particles become large, the particle size distribution becomes wide, and hematite is generated. Further, it is not economical to increase the amount of alkali hydroxide excessively.
前記出発原料の水溶液に水酸化アルカリを混合する方法
については、特に制限はないが、例えば出発原料の水溶
液に、直接水酸化アルカリを添加するか、あるいは水酸
化アルカリの水溶液を添加する方法がある。あるいはバ
リウム化合物を水酸化アルカリの水溶液側に加えて、こ
れと鉄を含む水溶液を混合する方法がある。There is no particular restriction on the method of mixing the alkali hydroxide into the aqueous solution of the starting material, but for example, there are methods of directly adding the alkali hydroxide or adding an aqueous solution of the alkali hydroxide to the aqueous solution of the starting material. . Alternatively, there is a method of adding a barium compound to the aqueous solution of alkali hydroxide and mixing this with an aqueous solution containing iron.
さらに、予め出発原料の水溶液あるいは水酸化アルカリ
の水溶液にＳｉ 、Ｃａなどの水に可溶性の化合物、例
えばケイ酸、ケイ酸ナトリウム、硝酸カルシウム、塩化
カルシウム等を若干添加することができる。これらの添
加物は粒子形状を制御するうえで好ましい。Furthermore, a small amount of water-soluble compounds such as Si and Ca, such as silicic acid, sodium silicate, calcium nitrate, and calcium chloride, can be added in advance to the aqueous solution of the starting material or the aqueous solution of alkali hydroxide. These additives are preferred for controlling particle shape.
次に、沈澱物を含むスラリを５０〜８０℃で十分に熟成
し、前駆体を形成させる。Next, the slurry containing the precipitate is sufficiently aged at 50 to 80°C to form a precursor.
次いで、熟成により生成したＩＲ細な結晶の沈澱物を水
洗して、遊離のアルカリ分を除去した後、得られた沈澱
物に融剤を混合する。融剤としては、塩化ナトリウム、
塩化カリウム、塩化バリウム、塩化ストロンチウムおよ
びフッ化ナトリウムのうち少なくとも一種が用いられる
。融剤の使用量は沈澱物（乾燥物基準）に対して、１０
〜１８０重量％、好ましくは３０〜１２０重量％が適当
である。融剤の量が少なすぎると粒子の焼結が起り、ま
た多すぎても多くしたことによる利点はなく、経済的で
ない、沈澱物と融剤の混合方法は特に制限はなく、例え
ば沈澱物のスラリに融剤を加えて湿式混合した後、スラ
リを乾燥してもよく、あるいは沈澱物を乾燥した後、融
剤を加えて乾式混合してもよい。Next, the precipitate of fine IR crystals produced by aging is washed with water to remove free alkali, and then a flux is mixed with the precipitate obtained. As a fluxing agent, sodium chloride,
At least one of potassium chloride, barium chloride, strontium chloride, and sodium fluoride is used. The amount of flux used is 10% for the precipitate (dry basis).
~180% by weight, preferably 30-120% by weight is suitable. If the amount of flux is too small, sintering of the particles will occur, and if it is too large, there is no advantage of increasing it and it is not economical. There is no particular restriction on the method of mixing the precipitate and the flux. After adding a flux to the slurry and wet-mixing, the slurry may be dried, or alternatively, after drying the precipitate, a flux may be added and dry-mixed.
次いで、得られた混合物を焼成することにより、バリウ
ムフェライトの結晶化が完全に行われる、焼成温度は７
００〜９５０℃、好ましくは８００〜９３０℃である。Next, the resulting mixture is fired to completely crystallize the barium ferrite, and the firing temperature is 7.
00-950°C, preferably 800-930°C.
温度が低ずぎると結晶化が進まず、飽和磁化が低くなる
。また温度が高ずざると粒子が大きくなったり、焼結が
起こるので好ましくない、ツエ成時間は１０分〜３０時
間程度が適当である。焼成雰囲気は特に制限されないが
、一般に空気雰囲気が便利である。If the temperature is too low, crystallization will not proceed and the saturation magnetization will become low. In addition, if the temperature is not high, the particles will become large and sintering will occur, which is undesirable, and the suitable time for the formation is about 10 minutes to 30 hours. The firing atmosphere is not particularly limited, but an air atmosphere is generally convenient.
得られた焼成物を洗浄後、濾過、乾燥することにより、
バリウムフェライト磁性粉が得られる。By washing, filtering and drying the obtained baked product,
Barium ferrite magnetic powder is obtained.
洗浄は焼成物中の融剤、過剰のバリウムなどの不純物を
十分に除去できればよどのような方法で行ってもよい、
洗浄液としては水や硝酸、塩酸などの無ｉ酸、酢酸、１
０ピオン酸などの有機酸などを用いることができる。Cleaning may be carried out by any method as long as impurities such as flux and excess barium in the fired product can be sufficiently removed.
Cleaning liquids include water, non-oxidizing acids such as nitric acid and hydrochloric acid, acetic acid,
Organic acids such as 0 pionic acid can be used.
（実施例）
実施例１
脱イオン水１３００ｍＮに、硝酸第二鉄［Ｆｅ（ＮＯ３
）３・９Ｈ２０」３．１２モル、硝酸コバルト［Ｃ０（
Ｎｏ３）２・６Ｈ２０］０．１２モル、および四塩化チ
タン（”Ｆｉ Ｃ１ａ ） ０．２４モルを溶解し、別
に脱イオン水１３００ｒｎＪｌに、水酸化バリウム［Ｂ
ａ（ＯＨ）２・８Ｈ２ｏコ０，３０モル、カセイソーダ
（ＮａＯＨ＞３７モルを溶解し、両溶液を混合して沈澱
物を生成させた。(Example) Example 1 Ferric nitrate [Fe(NO3
)3.9H20” 3.12 mol, cobalt nitrate [C0(
No.3)2.6H20] and 0.24 mole of titanium tetrachloride (Fi C1a) were dissolved, and separately, barium hydroxide [B
0.30 mole of a(OH)2.8H2o and caustic soda (>37 mole of NaOH) were dissolved, and both solutions were mixed to form a precipitate.
得られた沈澱物を含むスラリを８０℃で２０時間熟成を
行った０次いでｔｌ）られな沈澱物を十分に水洗した後
、濾過、乾燥し、これに融剤として、Ｎａ Ｃ，ＱとＢ
ａ ＣＯ２・２Ｈ２０の重量比が１：１の混合物を沈澱
物に対して１００重量？≦加えて混合した。この混合物
を空気雰囲気下で８６０”Ｃで２時間焼成した。得られ
た焼成物を水で十分水洗した後、濾過、乾燥してバリウ
ムフェライト磁性粉を得た。The resulting slurry containing the precipitate was aged at 80°C for 20 hours.Then, the unremoved precipitate was thoroughly washed with water, filtered and dried, and Na C, Q and B were added as fluxes.
a 100% by weight of a mixture of CO2/2H20 in a weight ratio of 1:1 to the precipitate? ≦Add and mix. This mixture was fired at 860''C in an air atmosphere for 2 hours.The resulting fired product was thoroughly washed with water, filtered and dried to obtain barium ferrite magnetic powder.
得られたバリウムフェライト磁性粉は、Ｘ線粉末回折ス
ペクトルおよび組成分析の結果、ＢａＯｏＦｅｌｏ、４
Ｃ００，４”０．８０１７．６であり、六方晶マグネ
トブランバイト型であった。As a result of X-ray powder diffraction spectrum and composition analysis, the obtained barium ferrite magnetic powder was found to be BaOoFelo, 4
C00.4"0.8017.6, and was of hexagonal magnetobrambite type.
またこのバリウムフェライト磁性粉について振動試料式
磁力計で磁気特性を測定した結果を第１表に示す、なお
、保磁力の温度変化は２０℃・〜１５０℃で測定した。The magnetic properties of this barium ferrite magnetic powder were measured using a vibrating sample magnetometer, and the results are shown in Table 1. Temperature changes in coercive force were measured at 20°C to 150°C.
実施例２〜１６
実施ＰＡｌに準じて第１表および第２表に示す組成のバ
リウムフェライト磁性粉を調製した。Examples 2 to 16 Barium ferrite magnetic powders having the compositions shown in Tables 1 and 2 were prepared according to PAl.
得られたバリウムフェライト磁性粉について振動試料式
磁力計で磁気特性を測定した結果を第１表および第２表
に示す、なお、保磁力の温度変化は２０℃〜１５０℃で
測定した。The magnetic properties of the obtained barium ferrite magnetic powder were measured using a vibrating sample magnetometer, and the results are shown in Tables 1 and 2. Temperature changes in coercive force were measured at 20°C to 150°C.
比較例１
脱イオン水１３００ｍＪｌに、硝酸第二鉄３．１２モル
、硝酸コバルト０．２４モルおよび四塩化チタン０．２
４モルを溶解し、別に脱イオン水１３００ｍ、Ｑに、水
酸化バリウム０．３０モルおよびカセイソーダ３７モル
を溶解し、両溶液を混合して沈澱物を生成させた。Comparative Example 1 3.12 mol of ferric nitrate, 0.24 mol of cobalt nitrate and 0.2 titanium tetrachloride in 1300 mJl of deionized water
Separately, in 1300 m of deionized water, 0.30 mole of barium hydroxide and 37 mole of caustic soda were dissolved, and both solutions were mixed to form a precipitate.
得られた沈澱物を含むスラリを８０℃で２０時間熟成を
行った。The slurry containing the obtained precipitate was aged at 80° C. for 20 hours.
次いで得られた沈澱物を十分に水洗した後、濾過、乾燥
し、これに融剤としてＮａ ＣＪとＢａｃＪ２・２Ｈ２
０との重量比で１：１の混合物を沈澱物に対して１００
重至％加えて混合した。この混合を空気雰囲気下で８６
０℃で２時間焼成した。得られた焼成物を水で十分水洗
した後、濾過、乾燥してバリウムフェライト磁性粉を得
た。Next, the obtained precipitate was thoroughly washed with water, filtered and dried, and Na CJ and BacJ2.2H2 were added as a fluxing agent.
1:1 mixture with 0 and 100% by weight to the precipitate.
% and mixed. This mixture was heated to 86°C under an air atmosphere.
It was baked at 0°C for 2 hours. The obtained fired product was thoroughly washed with water, filtered and dried to obtain barium ferrite magnetic powder.
得られたバリウムフェライト磁性粉は、Ｘ線粉末回折ス
ペクトルおよび組成分析の結果、Ｂ ａ Ｏ−Ｆ ｅｌ
ｏ、 ４ＣＯｏ、 ａＴ ｊ ｏ、 ａｏ １ａであり
、六方晶マグネトブランバイト型であった。As a result of X-ray powder diffraction spectrum and composition analysis, the obtained barium ferrite magnetic powder was found to be B a O-F el
o, 4COo, aT j o, ao 1a, and was of hexagonal magnetobrambite type.
またこのバリウムフェライト磁性粉について振動試料式
磁力計で磁気特性を測定した結果を第２表に示す、なお
、保磁力の温度変化は２０”Ｃ〜１５０℃で測定した。The magnetic properties of this barium ferrite magnetic powder were measured using a vibrating sample magnetometer, and the results are shown in Table 2. Temperature changes in coercive force were measured at 20"C to 150C.
比較例２〜４
比較例１に準じて第２表に示す組成のバリウムフェライ
ト磁性粉を調製した。Comparative Examples 2 to 4 According to Comparative Example 1, barium ferrite magnetic powder having the composition shown in Table 2 was prepared.
得られたバリウムフェライト磁性粉について振動試料式
磁力計で磁気特性を測定した結果を第１表に示す、なお
、保磁力の温度変化は２０”Ｃ〜１５０℃で測定した。The magnetic properties of the obtained barium ferrite magnetic powder were measured using a vibrating sample magnetometer, and the results are shown in Table 1. Temperature changes in coercive force were measured at 20"C to 150C.
（発明の効果）
本発明によれば、一般式
％式％
（ただし、ＡはＢａ、Ｓｒ、Ｐｂ、Ｃａ、Ｍ（ｌからな
る群から選ばれる一種以上の元素を示し、ＭはＣｏ、Ｎ
ｉ。(Effect of the invention) According to the present invention, the general formula % formula % (where A represents one or more elements selected from the group consisting of Ba, Sr, Pb, Ca, M(l), and M represents Co, N
i.
Ｃｕ、Ｚｎ等の２価元累、Ｔｉ、Ｓｎ、Ｚｒ、等の−１
価元素およびＮｂ、Ｖ、Ｍｏ、Ｗ等の５価元素からなる
群から選ばれる一種以上の元素または元素の組合わせを
示し、０．１＜ｘ＜２５．０．１＜ｙ＜ｘ、ｚ＝（３ｘ
−ｍｙ＞／２、かつＯくＺであり、ｍはＭの平均原子価
を表す、）で表される六方晶フェライト磁性粉が得られ
る。この六方晶フェライト磁性粉は従来のものと比較し
て、保磁力の温度変化が非常に小さく、磁気記録媒体に
用いるのに適している。-1 of divalent elements such as Cu, Zn, Ti, Sn, Zr, etc.
Indicates one or more elements or combinations of elements selected from the group consisting of valent elements and pentavalent elements such as Nb, V, Mo, W, etc., and 0.1<x<25.0.1<y<x, z =(3x
A hexagonal ferrite magnetic powder is obtained, where -my>/2 and O x Z, where m represents the average valence of M. This hexagonal ferrite magnetic powder has a very small temperature change in coercive force compared to conventional powders, and is suitable for use in magnetic recording media.
Claims (3)
＿８＿−＿ｚ（ただし、ＡはＢａ、Ｓｒ、Ｐｂ、Ｃａ、
Ｍｇからなる群から選ばれる一種以上の元素を示し、Ｍ
はＣｏ、Ｎｉ、Ｃｕ、Ｚｎ等の２価元素、Ｔｉ、Ｓｎ、
Ｚｒ、等の４価元素およびＮｂ、Ｖ、Ｍｏ、Ｗ等の５価
元素からなる群から選ばれる一種以上の元素または元素
の組合わせを示し、０．１＜ｘ＜２．５、０．１＜ｙ＜
ｘ、ｚ＝（３ｘ−ｍｙ）／２、かつ０＜ｚであり、ｍは
Ｍの平均原子価を表す。）で表される六方晶フェライト
磁性粉。(1) General formula AO・Fe_1_2_-_xM_yO_1
_8_-_z (However, A is Ba, Sr, Pb, Ca,
Indicates one or more elements selected from the group consisting of Mg,
is a divalent element such as Co, Ni, Cu, Zn, Ti, Sn,
Indicates one or more elements or a combination of elements selected from the group consisting of tetravalent elements such as Zr and pentavalent elements such as Nb, V, Mo, and W, and 0.1<x<2.5, 0. 1<y<
x, z=(3x-my)/2, and 0<z, and m represents the average valence of M. ) Hexagonal ferrite magnetic powder.
許請求の範囲第１項記載の六方晶フェライト磁性粉。(2) The hexagonal ferrite magnetic powder according to claim 1, wherein the hexagonal ferrite is barium ferrite.
、鉄が１２−ｘグラム原子、Ｍがｙグラム原子の割合の
それぞれの元素の化合物を用い、該出発原料を水に溶解
し、これに混合後の溶液中の水酸化アルカリ濃度が３モ
ル／ｌ以上となるように水酸化アルカリを加えて沈澱物
を生成させ、該沈澱物を含むスラリを５０〜８０℃で熟
成した後、生成した沈澱物に融剤を混合し、混合物を７
００〜９５０℃で焼成し、得られた焼成物を洗浄するこ
とを特徴とする 一般式ＢａＯ・Ｆｅ＿１＿２＿−＿ｘＭ＿ｙＯ＿１＿８
＿−＿ｚ（ただし、ＭはＣｏ、Ｎｉ、Ｃｕ、Ｚｎ等の２
価元素、Ｔｉ、Ｓｎ、Ｚｒ、等の４価元素およびＮｂ、
Ｖ、Ｍｏ、Ｗ等の５価元素からなる群から選ばれる一種
以上の元素または元素の組合わせを示し、０．１＜ｘ＜
２．５、０．１＜ｙ＜ｘ、ｚ＝（３ｘ−ｍｙ）／２、か
つ０＜ｚであり、ｍはＭの平均原子価を表す。）で表さ
れる六方晶フェライト磁性粉の製造方法。(3) As a starting material, a compound of each element is used in a ratio of 12-x gram atom of iron and y gram atom of M to 1 gram atom of barium, and the starting material is dissolved in water. Add alkali hydroxide to form a precipitate so that the alkali hydroxide concentration in the mixed solution is 3 mol/l or more, and after aging the slurry containing the precipitate at 50 to 80 ° C. Mix the flux with the precipitate and mix the mixture with
General formula BaO Fe_1_2_-_xM_yO_1_8 characterized by firing at 00 to 950°C and washing the obtained fired product
____z (However, M is 2 such as Co, Ni, Cu, Zn, etc.
valent elements, tetravalent elements such as Ti, Sn, Zr, and Nb,
Indicates one or more elements or combinations of elements selected from the group consisting of pentavalent elements such as V, Mo, and W, and 0.1<x<
2.5, 0.1<y<x, z=(3x-my)/2, and 0<z, where m represents the average valence of M. ) A method for manufacturing hexagonal ferrite magnetic powder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14520687A JPS63310730A (en) | 1987-06-12 | 1987-06-12 | Hexagonal ferrite magnetic powder and its production |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14520687A JPS63310730A (en) | 1987-06-12 | 1987-06-12 | Hexagonal ferrite magnetic powder and its production |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63310730A true JPS63310730A (en) | 1988-12-19 |
| JPH0432005B2 JPH0432005B2 (en) | 1992-05-28 |
Family
ID=15379850
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14520687A Granted JPS63310730A (en) | 1987-06-12 | 1987-06-12 | Hexagonal ferrite magnetic powder and its production |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63310730A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63185829A (en) * | 1986-09-19 | 1988-08-01 | Nippon Zeon Co Ltd | Magnetic powder for magnetic recording |
| US5062982A (en) * | 1989-04-07 | 1991-11-05 | Nippon Zeon Co., Ltd. | Magnetic powder for magnetic recording media |
| KR101989385B1 (en) * | 2017-12-22 | 2019-06-14 | 한국세라믹기술원 | Method For Manufacturing Rod Shaped Ferrite Particles |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5127874A (en) * | 1974-08-31 | 1976-03-09 | Matsushita Electric Ind Co Ltd | FUNSHASUINETSUHANNOHOHO OYOBI SOCHI |
| JPS62100419A (en) * | 1985-10-24 | 1987-05-09 | Nippon Zeon Co Ltd | Production of magnetic powder for magnetic recording |
-
1987
- 1987-06-12 JP JP14520687A patent/JPS63310730A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5127874A (en) * | 1974-08-31 | 1976-03-09 | Matsushita Electric Ind Co Ltd | FUNSHASUINETSUHANNOHOHO OYOBI SOCHI |
| JPS62100419A (en) * | 1985-10-24 | 1987-05-09 | Nippon Zeon Co Ltd | Production of magnetic powder for magnetic recording |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63185829A (en) * | 1986-09-19 | 1988-08-01 | Nippon Zeon Co Ltd | Magnetic powder for magnetic recording |
| US5062982A (en) * | 1989-04-07 | 1991-11-05 | Nippon Zeon Co., Ltd. | Magnetic powder for magnetic recording media |
| KR101989385B1 (en) * | 2017-12-22 | 2019-06-14 | 한국세라믹기술원 | Method For Manufacturing Rod Shaped Ferrite Particles |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0432005B2 (en) | 1992-05-28 |
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