JPS63159224A - Production of fine ba ferrite particle for magnetic recording - Google Patents
Production of fine ba ferrite particle for magnetic recordingInfo
- Publication number
- JPS63159224A JPS63159224A JP30391386A JP30391386A JPS63159224A JP S63159224 A JPS63159224 A JP S63159224A JP 30391386 A JP30391386 A JP 30391386A JP 30391386 A JP30391386 A JP 30391386A JP S63159224 A JPS63159224 A JP S63159224A
- Authority
- JP
- Japan
- Prior art keywords
- aqueous solution
- particles
- chloride
- salt
- 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.)
- Pending
Links
- 229910000859 α-Fe Inorganic materials 0.000 title claims abstract description 35
- 238000004519 manufacturing process Methods 0.000 title claims description 8
- 239000002245 particle Substances 0.000 title abstract description 44
- 239000007864 aqueous solution Substances 0.000 claims abstract description 26
- 150000002500 ions Chemical class 0.000 claims abstract description 24
- 239000002244 precipitate Substances 0.000 claims abstract description 20
- 230000004907 flux Effects 0.000 claims abstract description 18
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims abstract description 5
- 229910052700 potassium Inorganic materials 0.000 claims abstract description 3
- 229910052708 sodium Inorganic materials 0.000 claims abstract description 3
- 239000010419 fine particle Substances 0.000 claims description 15
- 239000000203 mixture Substances 0.000 claims description 11
- 238000001035 drying Methods 0.000 claims description 5
- 229910021645 metal ion Inorganic materials 0.000 claims description 4
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 abstract description 20
- WDIHJSXYQDMJHN-UHFFFAOYSA-L barium chloride Chemical compound [Cl-].[Cl-].[Ba+2] WDIHJSXYQDMJHN-UHFFFAOYSA-L 0.000 abstract description 12
- 229910001626 barium chloride Inorganic materials 0.000 abstract description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 12
- 229910021578 Iron(III) chloride Inorganic materials 0.000 abstract description 11
- XJDNKRIXUMDJCW-UHFFFAOYSA-J titanium tetrachloride Chemical compound Cl[Ti](Cl)(Cl)Cl XJDNKRIXUMDJCW-UHFFFAOYSA-J 0.000 abstract description 11
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 abstract description 10
- 238000005245 sintering Methods 0.000 abstract description 10
- 150000003839 salts Chemical class 0.000 abstract description 8
- -1 FeCl3 Chemical class 0.000 abstract description 6
- 238000010304 firing Methods 0.000 abstract description 6
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 abstract description 4
- HPGGPRDJHPYFRM-UHFFFAOYSA-J tin(iv) chloride Chemical compound Cl[Sn](Cl)(Cl)Cl HPGGPRDJHPYFRM-UHFFFAOYSA-J 0.000 abstract description 4
- 229910052719 titanium Inorganic materials 0.000 abstract description 4
- 229910021627 Tin(IV) chloride Inorganic materials 0.000 abstract description 3
- 150000002505 iron Chemical class 0.000 abstract description 2
- 229910021580 Cobalt(II) chloride Inorganic materials 0.000 abstract 1
- 229910003074 TiCl4 Inorganic materials 0.000 abstract 1
- 239000003513 alkali Substances 0.000 abstract 1
- 239000010936 titanium Substances 0.000 description 16
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 15
- 239000002994 raw material Substances 0.000 description 13
- 238000000034 method Methods 0.000 description 12
- WCUXLLCKKVVCTQ-UHFFFAOYSA-M Potassium chloride Chemical compound [Cl-].[K+] WCUXLLCKKVVCTQ-UHFFFAOYSA-M 0.000 description 9
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 8
- GVPFVAHMJGGAJG-UHFFFAOYSA-L cobalt dichloride Chemical compound [Cl-].[Cl-].[Co+2] GVPFVAHMJGGAJG-UHFFFAOYSA-L 0.000 description 8
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 6
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 6
- 229910052742 iron Inorganic materials 0.000 description 6
- 239000000843 powder Substances 0.000 description 6
- 238000001354 calcination Methods 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 5
- 238000002156 mixing Methods 0.000 description 5
- 239000003795 chemical substances by application Substances 0.000 description 4
- 230000005415 magnetization Effects 0.000 description 4
- 239000001103 potassium chloride Substances 0.000 description 4
- 235000011164 potassium chloride Nutrition 0.000 description 4
- 239000011780 sodium chloride 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
- 229910052788 barium Inorganic materials 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 238000010908 decantation Methods 0.000 description 3
- 230000004927 fusion Effects 0.000 description 3
- 239000006247 magnetic powder Substances 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 229910000029 sodium carbonate Inorganic materials 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- AYJRCSIUFZENHW-UHFFFAOYSA-L barium carbonate Chemical compound [Ba+2].[O-]C([O-])=O AYJRCSIUFZENHW-UHFFFAOYSA-L 0.000 description 2
- 229910001422 barium ion Inorganic materials 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
- 239000011230 binding agent Substances 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 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 2
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 2
- 239000011734 sodium Substances 0.000 description 2
- 229910052938 sodium sulfate Inorganic materials 0.000 description 2
- 235000011152 sodium sulphate Nutrition 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 108091006629 SLC13A2 Proteins 0.000 description 1
- 229910004356 Ti Raw Inorganic materials 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical group [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 150000001805 chlorine compounds Chemical class 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 230000015271 coagulation Effects 0.000 description 1
- 238000005345 coagulation Methods 0.000 description 1
- 229910000361 cobalt sulfate Inorganic materials 0.000 description 1
- 229940044175 cobalt sulfate Drugs 0.000 description 1
- KTVIXTQDYHMGHF-UHFFFAOYSA-L cobalt(2+) sulfate Chemical compound [Co+2].[O-]S([O-])(=O)=O KTVIXTQDYHMGHF-UHFFFAOYSA-L 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 159000000014 iron salts Chemical class 0.000 description 1
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 description 1
- 229910000360 iron(III) sulfate Inorganic materials 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 230000005381 magnetic domain Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- DCKVFVYPWDKYDN-UHFFFAOYSA-L oxygen(2-);titanium(4+);sulfate Chemical compound [O-2].[Ti+4].[O-]S([O-])(=O)=O DCKVFVYPWDKYDN-UHFFFAOYSA-L 0.000 description 1
- 229910000027 potassium carbonate Inorganic materials 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 239000007921 spray Substances 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
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 229910000348 titanium sulfate Inorganic materials 0.000 description 1
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
この発明は、Ｂａフェライト微粒子特に磁気記録媒体と
して用いられる磁性粉としての用途に供して好適なりａ
フェライトａ粒子の製造方法に関する。Detailed Description of the Invention (Field of Industrial Application) The present invention is suitable for use as Ba ferrite fine particles, particularly as magnetic powder used as a magnetic recording medium.
The present invention relates to a method for producing ferrite a particles.
（従来の技術）
磁気記録媒体に用いられる磁性粉に要求される特性とし
ては、粉体特性及び磁気特性がよいことが挙げられる。(Prior Art) Characteristics required of magnetic powder used in magnetic recording media include good powder characteristics and magnetic characteristics.
すなわち粉体特性としては、粒径が０．４μｍ以下で粒
径が揃い、しがも粒子間に焼結がなく、バインダー中に
粒子が分散しゃすいこと、一方磁気特性としては、飽和
磁化が太き（、かつ保持力が５０００ｅ〜３００００ｅ
程度であることが要求される。In other words, the powder properties are that the particle size is 0.4 μm or less, the particle size is uniform, there is no sintering between particles, and the particles are easily dispersed in the binder, and the magnetic properties are that saturation magnetization is low. Thick (and holding force is 5000e~30000e)
degree is required.
ところで従来、粒子間に焼結や融着等のない粒子を得る
方法としては、原料を焼成する際に融剤を添加する方法
が知られていて、たとえば特公昭５５−４９０３０号公
報に開示の方法では、融剤成分として塩化バリウムや塩
化ストロンチウムを用いて焼成を行っている。By the way, conventionally, as a method of obtaining particles without sintering or fusion between particles, a method of adding a flux when firing raw materials has been known, for example, as disclosed in Japanese Patent Publication No. 55-49030. In this method, calcination is performed using barium chloride or strontium chloride as a flux component.
しかしながら、これらの融剤は粒子同士の接触による焼
結、融着は防止できるものの、融液相中のフェライト成
分がフェライト粒子に凝縮することに起因して粒子の結
晶成長が促進されるので粒子を小さくすることは極めて
難しかった。また特公昭５７−２１５１７号公報に開示
の方法では、Ｂａ ＋ Ｓｒ等のフェライト粒子粉末に
ＮａＣ１、ＢａＣ１ｘなどの融剤を加えて焼成を行い粒
子形状の制御を行っているが、原料として仮焼品を粉砕
した粉末を用いているため、焼成品の粒径は１μｍ程度
にもなり磁気記録用としては粒径が大きすぎる欠点があ
った。However, although these fluxes can prevent sintering and fusion due to contact between particles, they promote the crystal growth of particles due to the condensation of ferrite components in the melt phase onto ferrite particles. It was extremely difficult to make it smaller. In addition, in the method disclosed in Japanese Patent Publication No. 57-21517, the shape of the particles is controlled by adding a fluxing agent such as NaCl or BaClx to ferrite particle powder such as Ba + Sr and sintering. Since powder obtained by pulverizing the product is used, the particle size of the fired product is about 1 μm, which has the drawback of being too large for magnetic recording.
さらに特開昭５８−１６９９０２号公報に開示の方法で
は、ガラス組成物中にＢａフェライト微粒子を析出させ
ているが、ガラス組成物を除去するのに酢酸を大量に必
要とし、しかも、処理に長時間を要することから経済的
な面で難があった。Furthermore, in the method disclosed in JP-A-58-169902, Ba ferrite fine particles are precipitated in a glass composition, but a large amount of acetic acid is required to remove the glass composition, and the treatment is long. It was economically difficult because it was time consuming.
（発明が解決しようとする問題点）
この発明は、上記の問題を有利に解決するもので、磁気
記録の高密度化に適切に対応し得る、粒子が微小で、粒
子間に焼結がなく、粒径が揃っているだけでなく、優れ
た磁気特性をそなえ、しかもバインダーとの複合化の際
に優れた分散性を有するＢａフェライト微粒子を安価に
得ることができる製造方法を提案することを目的とする
。(Problems to be Solved by the Invention) The present invention advantageously solves the above-mentioned problems, and has minute particles and no sintering between particles, which can appropriately correspond to higher density magnetic recording. The purpose of the present invention is to propose a manufacturing method that can inexpensively obtain Ba ferrite fine particles that not only have uniform particle sizes but also have excellent magnetic properties and excellent dispersibility when combined with a binder. purpose.
（問題点を解決するための手段） まずこの発明の解明経緯について説明する。(Means for solving problems) First, the background to the elucidation of this invention will be explained.
Ｂａフェライトを製造する場合、一般的には炭酸バリウ
ムおよび酸化鉄の粉末を原料とし、これらを混合した後
反応させる方法がとられている。しかしながらこの反応
は酸化鉄粉末粒子の表面から内部にバリウムイオンが拡
散することによって起こるものであるため、生成したＢ
ａフェライト粒子は原理的に酸化鉄粒子より小さくする
ことはできない。When producing Ba ferrite, a method is generally used in which powders of barium carbonate and iron oxide are used as raw materials, mixed together, and then reacted. However, this reaction occurs due to the diffusion of barium ions from the surface of the iron oxide powder particles into the interior, so the generated B
In principle, a-ferrite particles cannot be made smaller than iron oxide particles.
ところで水？容液中でＦｅイオンとＢａイオンを同時に
沈澱させた場合、沈澱物は非晶質状もしくは非常に微小
な粒子になっていて、ＦｅとＢａがイオン単位で隣接し
ているので、反応のための拡散はわずかでよく、従って
粒成長が進まないうちに反応を完了できる。By the way, water? When Fe ions and Ba ions are precipitated simultaneously in a solution, the precipitate is amorphous or very small particles, and Fe and Ba are adjacent in ion units, so it is difficult for the reaction to occur. Only a small amount of diffusion is required, so the reaction can be completed before grain growth progresses.
そこで発明者らは、かかる水溶液中での沈澱物を原料と
してＢａフェライトを製造すべ（、鋭意研究を重ねた結
果、以下に述べる知見を得た。Therefore, the inventors have conducted extensive research to produce Ba ferrite using the precipitate in such an aqueous solution as a raw material, and have obtained the knowledge described below.
さて実際にこの沈澱物を用いて粒子を製造しようとする
場合に、まず問題となったのは、粒子間の凝結が極めて
強いために粒子は非常に焼結し易く、その結果融着や結
着を起こすので粒子をバラバラにすることができないこ
とであった。Now, when actually trying to manufacture particles using this precipitate, the first problem was that the coagulation between the particles was extremely strong, making the particles very easy to sinter, resulting in fusion and sintering. The problem was that it was impossible to break up the particles because this would cause deposition.
そこでこの粒子間の焼結を防ぐべく共沈物に融剤を添加
することとした。Therefore, we decided to add a flux to the coprecipitate in order to prevent this sintering between particles.
なおその際用いる融剤としては、粒成長を抑え、しかも
反応を促進させるような特性を持つものが望ましい。The flux used in this case is preferably one that suppresses grain growth and promotes the reaction.
しかしながらＢａフェライト粒子がその単磁区径を下回
るような粒径になった場合には、保磁力が大きくなりす
ぎて、磁気記録用として用いるには適当でなかった。そ
こでこの点については、保磁力を小さくすぺ（Ｆｅイオ
ンを他の金属イオンで置換することにした。なおその際
置換する金属イオンとしては、保磁力は小さくするが飽
和磁化は小さくしないような作用をもつものが望ましい
。However, when the Ba ferrite particles have a particle size smaller than the single magnetic domain diameter, the coercive force becomes too large, making it unsuitable for use in magnetic recording. Therefore, regarding this point, we decided to reduce the coercive force (replace the Fe ions with other metal ions).In addition, as for the metal ions to be replaced, we decided to reduce the coercive force but not reduce the saturation magnetization. It is desirable to have something that works.
以上のことを考慮して、融剤の選択、置換イオンの選択
および種々の条件下での製造を数多く試みた末に、この
発明を完成させるに至ったのである。In consideration of the above, the present invention was completed after many attempts to select a flux, select a substituent ion, and manufacture under various conditions.
すなわちこの発明は、Ｆｅ”イオン、 Ｂａ”イオンお
よびＣｏ”イオンを、Ｔｉ４°イオンおよびＳｎ”イオ
ンの少なくとも一種と共に含有し、かつこれらの金属イ
オンの原子比をそれぞれ
（Ｆｅ ＋ Ｃｏ ＋ Ｔｉ ＋ Ｓｎ）／Ｂａ ：
１０〜１３Ｃｏ／（Ｔｉ ＋ Ｓｎ） ： ０．８〜１
．２Ｆｅ／（Ｃｏ ＋ Ｔｉ ＋ Ｓｎ） ： ５．８
〜１５の範囲に調整した水溶液と、アルカリ水溶液とを
混合し、ｐＨ ： １０以上において沈澱物を得たのち
、該沈澱物をそのｐ）ｌが６〜９となるまで中和してか
ら、融剤としてＮａまたはＫの塩化物あるいは硫酸塩の
うちから選んだ少なくとも一種を、乾燥後の重量が全重
量の５ｗｔ％以上となる範囲において配合し、しかるの
ち６００〜１２００℃の温度範囲で焼成することから成
る磁気記録用Ｂａフェライト微粒子の製造方法である。That is, this invention contains Fe" ions, Ba" ions, and Co" ions together with at least one of Ti4° ions and Sn" ions, and the atomic ratio of these metal ions is (Fe + Co + Ti + Sn). )/Ba:
10~13Co/(Ti+Sn): 0.8~1
．． 2Fe/(Co + Ti + Sn): 5.8
An aqueous solution adjusted to a pH of ~15 and an alkaline aqueous solution are mixed to obtain a precipitate at a pH of 10 or more, and the precipitate is neutralized until its p)l becomes 6 to 9. At least one selected from Na or K chloride or sulfate is blended as a flux in a range such that the weight after drying is 5 wt% or more of the total weight, and then calcined at a temperature range of 600 to 1200 ° C. This is a method for producing Ba ferrite particles for magnetic recording.
以下この発明を具体的に説明する。This invention will be specifically explained below.
この発明では微小なりａフェライト粒子を得るため、原
料としてＦｅ！＋ 、 Ｂａ！＋ 、 Ｃｏｔ＊ 、
７１４ｅ 、 Ｓｎ４＋を含む水溶液からの共沈物を用
いる。 Ｆｅ原料は水可溶性の鉄塩であればいかなるも
のでもよいが、塩化第２鉄、硝酸第２鉄および硫酸第２
鉄等がとりわけ有利に適合する。なおかかる鉄塩は単独
使用してもまた併用してもいずれでもよいのはいうまで
もない。またＢａ原料も水可溶性のＢａ塩であればいか
なるものでもよいが塩化バリウム、硝酸バリウム等が有
利に適合する。In this invention, in order to obtain minute ferrite particles, Fe! +, Ba! +, Cot*,
714e, using a coprecipitate from an aqueous solution containing Sn4+. The Fe raw material may be any water-soluble iron salt, including ferric chloride, ferric nitrate, and ferric sulfate.
Iron and the like are particularly advantageously suited. It goes without saying that these iron salts may be used alone or in combination. Further, the Ba raw material may be any water-soluble Ba salt, but barium chloride, barium nitrate, etc. are advantageously suitable.
その他ｃｏ原料としては、水可溶性のＣｏ塩である塩化
コバルトや硫酸コバルト等が、またＴｉ原料としては、
水可溶性のＴｉ塩である塩化チタンや硫酸チタン等が、
さらにＳｎ原料としては、水可溶性のＳｎ塩である塩化
スズ等が好適であり、これらのＢａ原料やＣｏ原料、Ｔ
ｉ原料およびＳｎ原料はいずれも、Ｆｅ原料同様、各基
を単独で使用してもまた併用してもかまわない。Other Co raw materials include water-soluble Co salts such as cobalt chloride and cobalt sulfate, and Ti raw materials include:
Water-soluble Ti salts such as titanium chloride and titanium sulfate are
Further, as the Sn raw material, water-soluble Sn salt such as tin chloride is suitable, and these Ba raw materials, Co raw materials, T
As with the Fe raw material, each of the i raw material and the Sn raw material may be used alone or in combination.
次に水溶液中のＦｅ”イオン、 Ｂａ”イオン。Next, Fe'' ions and Ba'' ions in the aqueous solution.
Ｃｏ”イオン Ｔ １４ ＋イオンおよび５ｎ４＊イオ
ンの原子比を上記の範囲に限定した理由について説明す
る。The reason why the atomic ratio of Co'' ion T 14 + ion and 5n4* ion is limited to the above range will be explained.
まずＢａに対する（Ｆｅ ＋ Ｃｏ ＋ Ｔｉ ＋ Ｓ
ｎ）の比（Ｆｅ ＋Ｃｏ ＋ Ｔｉ ＋ Ｓｎ）／Ｂａ
を１０〜１３としたのは（Ｐｅ ＋ Ｃｏ ＋Ｔｉ ＋
Ｓｎ）／Ｂａが１０未満の場合には主としてＢａＯ・
２ＦｅｚＯｓ （ＢａＦｅ＊（１＋）のような結晶構造
を持つ非磁性組成物が生成し、一方１３を超えた場合に
は主としてＦｅ２Ｏ２などの非磁性組成物が生成し、い
ずれにしても良好な磁気特性が得られないからである。First, for Ba (Fe + Co + Ti + S
n) ratio (Fe + Co + Ti + Sn)/Ba
The reason for setting 10 to 13 is (Pe + Co + Ti +
When Sn)/Ba is less than 10, it is mainly BaO.
A non-magnetic composition with a crystal structure such as 2FezOs (BaFe*(1+)) is produced, while if it exceeds 13, a non-magnetic composition such as Fe2O2 is produced, and in any case, it has good magnetic properties. This is because it cannot be obtained.
またＣｏ／（Ｔｉ ＋ Ｓｎ）を０．８〜１．２とした
のは、Ｃｏ／（Ｔｉ ＋ Ｓｎ）が０．８未満及び１．
２を越える場合には結晶内の電気的中性を保つために、
Ｂａフェライトの化学量論的組成からのずれが生じ磁気
特性が悪化するからである。Moreover, the reason why Co/(Ti + Sn) is set to 0.8 to 1.2 is that Co/(Ti + Sn) is less than 0.8 and 1.
If it exceeds 2, to maintain electrical neutrality within the crystal,
This is because a deviation from the stoichiometric composition of Ba ferrite occurs and the magnetic properties deteriorate.
さらにＰｅ／（Ｃｏ ＋ Ｔｉ ＋ Ｓｎ）を５．８〜
１５としたのは、Ｆｅ／（Ｃｏ ＋ Ｔｉ ＋ Ｓｎ）
が５．８未満の場合には保磁力が５０００ｅ未満となり
、一方１５を超えた場合には保磁力が３００００ｅを超
え、やはり磁気記録媒体として適さなくなるからである
。Furthermore, Pe/(Co + Ti + Sn) is 5.8~
15 is Fe/(Co + Ti + Sn)
If it is less than 5.8, the coercive force will be less than 5,000e, while if it exceeds 15, the coercive force will be more than 30,000e, making it unsuitable as a magnetic recording medium.
次に上記したようなＦｅ”イオン、 Ｂａ”イオン。Next, Fe" ions and Ba" ions as described above.
Ｃｏ”“イオン、 Ｔｉ”イオンおよびＳｎ’“イオン
を所定量含む水溶液とアルカリ水溶液とを混合し、ｐＨ
を１０以上としてＲｅ 、 Ｂａ 、 Ｃｏ 、 Ｔｉ
およびＳｎの共沈物を得る。アルカリ水溶液としては、
いかなるものでもよいが、中でも水酸化ナトリウム、水
酸化カリウム、炭酸ナトリウムおよび炭酸カリウム水溶
液等が好適である。An aqueous solution containing a predetermined amount of Co"" ions, Ti" ions, and Sn'" ions is mixed with an alkaline aqueous solution, and the pH is adjusted.
Re, Ba, Co, Ti with 10 or more
and Sn coprecipitate. As an alkaline aqueous solution,
Any solution may be used, but aqueous solutions of sodium hydroxide, potassium hydroxide, sodium carbonate, and potassium carbonate are particularly suitable.
ここで沈澱物を生成させる際、溶液のｐＨを１０以上に
限定したのは、ｐｉが１０未満の状態であると金属陽イ
オンが十分沈澱せず、この場合には組成ずれを起こして
好ましい磁気特性が得られなくなるからである。The reason why the pH of the solution was limited to 10 or more when generating the precipitate is that if pi is less than 10, the metal cations will not precipitate sufficiently, and in this case, a composition deviation will occur, resulting in a preferable magnetic field. This is because the characteristics cannot be obtained.
ついで上記の共沈物は、デカンテーシヨンにより水洗を
行うか、あるいは塩酸、硫酸等の酸を加えてｐｎを６〜
９に調整する。Next, the above coprecipitate is washed with water by decantation, or an acid such as hydrochloric acid or sulfuric acid is added to reduce the pn to 6 to 6.
Adjust to 9.
というのはｐ）１９を超えて共沈物中にアルカリ成分が
残っているとＢａフェライトよりも非磁性の組成物のほ
うが優先的に生成することがあり、一方ｐｕが６未満の
水溶液中では共沈物は溶解して組成ずれを起こすことが
あり、いずれにしてもＢａフェライト製造上好ましくな
いからである。This is because if p) exceeds 19 and alkaline components remain in the coprecipitate, a non-magnetic composition may be preferentially formed than Ba ferrite, whereas in an aqueous solution with p<6, coprecipitation will occur. This is because the materials may melt and cause a composition shift, which is undesirable in any case for the production of Ba ferrite.
その後かかる共沈物に融剤を混合する。この際共沈物を
乾燥した後、融剤を添加してもよいが、より細かい微粒
子を得るには共沈物を含む融剤の溶解した水溶液をスプ
レードライ、コールドドライ等の手法を用いて急速乾燥
させることが好ましい。A fluxing agent is then mixed into the coprecipitate. At this time, a flux may be added after drying the coprecipitate, but to obtain finer particles, an aqueous solution containing the coprecipitate and a flux dissolved therein may be spray-dried, cold-dried, etc. Rapid drying is preferred.
ここに融剤としては、Ｎａ’ＰＫの塩化物または硫酸塩
のうちから選んだ少なくとも一種を用いる。As the fluxing agent, at least one selected from chlorides and sulfates of Na'PK is used.
というのはこれらの融剤は水溶性であるため水洗により
容易に除去できるだけでなく、コストの点でも有利だか
らである。This is because these fluxes are water-soluble and can be easily removed by washing with water, and are also advantageous in terms of cost.
また融剤の配合割合は、少なくとも乾燥後の全重量の５
ｗｔχ（以下単に％で示す）以上好ましくは５〜７０％
とする必要がある。というのは配合割合が５％を下回る
と融剤の添加効果が十分には発揮されないからである。The mixing ratio of the fluxing agent should be at least 5% of the total weight after drying.
wtχ (hereinafter simply expressed as %) or more preferably 5 to 70%
It is necessary to do so. This is because, if the blending ratio is less than 5%, the effect of adding the flux will not be sufficiently exhibited.
しかるのち、６００〜１２００℃の温度範囲で焼成する
ことによって製品とする。Thereafter, the product is baked at a temperature range of 600 to 1200°C.
ここに焼成温度を６００〜１２００℃の範囲に限定した
のは、焼成温度が６００℃に満たない場合にはフェライ
ト化反応が不十分であり、一方１２００℃を超えた場合
には粒成長が進み過ぎて粒径が大きくなり、十分満足の
いく磁気特性が得られないからである。なお焼成時間は
、０．５時間以上程度、好ましくは１〜３時間である。The reason why the firing temperature is limited to the range of 600 to 1200°C is that if the firing temperature is less than 600°C, the ferrite reaction will be insufficient, whereas if it exceeds 1200°C, grain growth will proceed. This is because if it is too large, the particle size will become large, making it impossible to obtain sufficiently satisfactory magnetic properties. The firing time is about 0.5 hours or more, preferably 1 to 3 hours.
（実施例）
実施例１
塩化バリウム（ＢａＣ１ｇ ・２ＨｚＯ） ： １５．
２５ｇ−塩化第２鉄（ＦｅＣ１ｓ ・６ＨｇＯ） ：
１Ｂ９．１５８１塩化コバルト：（ＣｏＣ１ｇ ・６Ｈ
！Ｏ） ： ５．９５ｇ及び四塩化チタン（ＴｉＣ１＃
）Ｃ４，７４ｇを水ＩＩｔに溶解した水溶液を準備し、
水酸化ナトリウム（ＮａＯＨ）： ２５０．０ｇ及び炭
酸ナトリウム（ＮａｚＣＯｓ） ： ６２−５ｇを水２
１に溶解した水溶液中に、前記Ｂａ 、 Ｆｅ 、 Ｃ
ｏ 、 Ｔｉを含む水溶液を攪拌しながら混合すること
により沈澱物を得た。このときのｐＨは１１であった。(Example) Example 1 Barium chloride (BaC1g 2HzO): 15.
25g-ferric chloride (FeCls 6HgO):
1B9.1581 Cobalt chloride: (CoC1g ・6H
! O): 5.95g and titanium tetrachloride (TiC1#
) Prepare an aqueous solution in which 74 g of C4 is dissolved in water IIt,
Sodium hydroxide (NaOH): 250.0g and sodium carbonate (NazCOs): 62-5g in 2 parts water
In the aqueous solution dissolved in 1, the Ba, Fe, C
A precipitate was obtained by mixing an aqueous solution containing o and Ti with stirring. The pH at this time was 11.
かくして得られた沈澱物をデカンテーションによりｐＨ
が８になるまで水洗し、ろ過後、乾燥した。The pH of the thus obtained precipitate was adjusted by decantation.
It was washed with water until the pH value reached 8, filtered, and dried.
その後得られた沈澱物に塩化カリウム（ＭＣＩ）を７０
ｇ添加、混合したのち、電気炉中で８００℃、２時間の
焼成を施し、しかるのち温水で水洗してがら乾燥させた
。Thereafter, 70% potassium chloride (MCI) was added to the resulting precipitate.
After adding g and mixing, the mixture was fired at 800° C. for 2 hours in an electric furnace, and then dried while washing with warm water.
かくして得られたＢａフェライト微粒子の平均粒径、保
磁力および飽和磁化について調べた結果を後掲の表１に
示す。The average particle diameter, coercive force, and saturation magnetization of the Ba ferrite fine particles thus obtained are shown in Table 1 below.
なおかかるＢａフェライト微粒子は、粒子間に焼結もな
く、また粒径のそろった微粒子であった。The Ba ferrite fine particles had no sintering between the particles and had uniform particle sizes.
実施例２
水溶液として塩化バリウム： １５．２５ｇ、塩化第２
鉄： １８２．３９ｇ 、塩化コバルト： ８．９２ｇ
及び四塩化チタン： ７．１１ｇを用いた他は実施例１
と同様に処理した。Example 2 Barium chloride as an aqueous solution: 15.25 g, ferric chloride
Iron: 182.39g, Cobalt chloride: 8.92g
and titanium tetrachloride: Example 1 except that 7.11 g was used.
processed in the same way.
かくして得られたＢａフェライト微粒子の緒特性につい
て調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite fine particles thus obtained.
実施例３
焼成を１２００℃で行ったことの他は実施例２と同様に
処理した。Example 3 The same process as in Example 2 was carried out except that the firing was performed at 1200°C.
かくして得られたＢａフェライト微粒子の緒特性につい
て調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite fine particles thus obtained.
実施例４
塩化バリウム： １５．２５ｇ、塩化第２鉄： １７９
．８６ｇ 。Example 4 Barium chloride: 15.25g, ferric chloride: 179
．． 86g.
塩化コバルト： ８．９２ｇ 、四塩化チタン： ８．
８９ｇを用いた他は実施例１と同様に処理した。Cobalt chloride: 8.92g, titanium tetrachloride: 8.
The process was carried out in the same manner as in Example 1 except that 89 g was used.
かくして得られたＢａフェライト微粒子の緒特性につい
て調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite fine particles thus obtained.
実施例５
水溶液として塩化バリウム： １５．２５ｇ、塩化第２
鉄： １７５．６４ｇ 、塩化コバルト： １１．８９
ｇ及び四塩化チタン： ９．４９ｇを用いた他は実施例
１と同様に処理した。Example 5 Barium chloride as an aqueous solution: 15.25 g, ferric chloride
Iron: 175.64g, Cobalt chloride: 11.89
g and titanium tetrachloride: Processed in the same manner as in Example 1 except that 9.49 g was used.
かくして得られたＢａフェライト微粒子の緒特性につい
て調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite fine particles thus obtained.
実施例６
塩化バリウム： １５．２５ｇ、塩化第２鉄： １８２
．３９ｇ 。Example 6 Barium chloride: 15.25g, ferric chloride: 182
．． 39g.
塩化コバル） ： ８．９２ｇ及び四塩化チタン： ７
．１１ｇを水１１に溶解した水溶液を準備し、水酸化ナ
トリウム： ２５０．Ｏｇ及び炭酸ナトリウム： ６２
．５ｇを水２１に溶解した水溶液中に、前記Ｂａ 、
Ｆｅ 、 Ｃｏ 。Cobal chloride): 8.92g and titanium tetrachloride: 7
．． Prepare an aqueous solution in which 11 g of sodium hydroxide is dissolved in 11 of water, and sodium hydroxide: 250. Og and sodium carbonate: 62
．． In an aqueous solution in which 5 g of Ba is dissolved in water 21,
Fe, Co.
Ｔｉを含む水溶液を攪拌しながら混合することにより沈
澱物を得た（混合液のｐＨ： １１）。A precipitate was obtained by mixing the aqueous solution containing Ti with stirring (pH of the mixed solution: 11).
かくして得られた沈澱物をデカンテーションによりｐＨ
が８になるまで水洗した。その後この沈澱物を含有する
水溶液に、塩化ナトリウム（ＮａＣ１）と塩化カリウム
（ＫＣＩ）と硫酸ナトリウム（ＮａｚＳＯｔ）とが等モ
ル比である混合物を７０ｇ添加・溶解させたのち、スプ
レードライヤーにて乾燥させた。しかるのち、電気炉中
で６００℃、２時間の焼成を施した後、温水で洗浄して
から乾燥させた。The pH of the thus obtained precipitate was adjusted by decantation.
It was washed with water until it reached a value of 8. Thereafter, 70 g of a mixture of sodium chloride (NaC1), potassium chloride (KCI), and sodium sulfate (NazSOt) in an equimolar ratio was added and dissolved in the aqueous solution containing this precipitate, and then dried with a spray dryer. Ta. Thereafter, it was fired at 600° C. for 2 hours in an electric furnace, washed with warm water, and then dried.
かくして得られたＢａフェライ＋−ａ粒子の緒特性につ
いて調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite+-a particles thus obtained.
実施例７
塩化バリウム： １６．６５ｇ、塩化第２鉄： １８２
．３９ｇ 。Example 7 Barium chloride: 16.65g, ferric chloride: 182
．． 39g.
塩化コバルト： ８．９２ｇ及び四塩化チタン： ７．
１１ｇを用いて沈澱物を得、融剤として塩化ナトリウム
（ＮａＣ１） ７０ｇを用い、焼成を９００℃で行った
ことの他は実施例６と同様に処理した。Cobalt chloride: 8.92g and titanium tetrachloride: 7.
The same procedure as in Example 6 was carried out except that 11 g of the precipitate was used to obtain a precipitate, 70 g of sodium chloride (NaCl) was used as a flux, and the calcination was performed at 900°C.
かくして得られたＢａフェライト微粒子の緒特性につい
て調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite fine particles thus obtained.
実施例８
四基チタンニア、１１ｇのかわりに、塩化第２すず（Ｓ
ｎＣ１ｔ） ： ９．７７ｇを用いて沈澱物を得、融剤
として塩化カリウム： ７０ｇを用い、焼成を８００℃
で行ったことの他は実施例６と同様に処理した。Example 8 Instead of 11 g of quaternary titanium nia, stannic chloride (S
nC1t): 9.77 g was used to obtain a precipitate, potassium chloride: 70 g was used as a flux, and calcination was carried out at 800°C.
The process was carried out in the same manner as in Example 6 except for the steps described in .
かくして得られたＢａフェライト微粒子の緒特性につい
て調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite fine particles thus obtained.
実施例９
塩化バリウム： １５．２５ｇ、塩化第２鉄： １Ｂ２
．３９ｇ 。Example 9 Barium chloride: 15.25g, ferric chloride: 1B2
．． 39g.
塩化コバルト？ ８．９２ｇ 、四塩化チタン？ ３．
５６．及び塩化第２すず： ４．８９ｇを用いて沈澱物
を得、融剤として塩化カリウムニア０ｇを用い、焼成を
８００℃で行ったことの他は実施例６と同様に処理した
。Cobalt chloride? 8.92g, titanium tetrachloride? 3.
56. and stannic chloride: A precipitate was obtained using 4.89 g, and the same treatment as in Example 6 was performed except that 0 g of potassium chloride nia was used as a flux and the calcination was performed at 800°C.
かくして得られたＢａフェライト微粒子の緒特性につい
て調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite fine particles thus obtained.
比較例１
塩化バリウム： １５．２５ｇ、塩化第２鉄： １７２
．２６ｇ 。Comparative Example 1 Barium chloride: 15.25g, ferric chloride: 172
．． 26g.
塩化コバル） ： １３．３８ｇ及び四塩化チタン：
１０．６７ｇを用いた他は実施例１と同様に処理した。Cobal chloride): 13.38g and titanium tetrachloride:
The process was carried out in the same manner as in Example 1 except that 10.67 g was used.
かくして得られたＢａフェライト微粒子の緒特性につい
て調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite fine particles thus obtained.
比較例２
塩化バリウム： １５．２５ｇ、塩化第２鉄： １９２
．５２ｇ 。Comparative Example 2 Barium chloride: 15.25g, ferric chloride: 192
．． 52g.
塩化コバルト： ４．４６ｇ 、四塩化チタン： ３．
５６ｇを用いた他は実施例１と同様に処理した。Cobalt chloride: 4.46g, titanium tetrachloride: 3.
The treatment was carried out in the same manner as in Example 1 except that 56 g was used.
かくして得られたＢａフェライ１粒子の緒特性について
調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite 1 particles thus obtained.
比較例３
融剤として硫酸ナトリウム（ＮａｚＳＯ＊） ： ７０
ｇを用い、焼成を１３００℃で行ったことの他は実施例
２と同様に処理した。Comparative Example 3 Sodium sulfate (NazSO*) as flux: 70
The process was carried out in the same manner as in Example 2, except that calcination was performed at 1300°C.
かくして得られたＢａフエライ１粒子の緒特性について
調べた結果を表１に示す。Table 1 shows the results of investigating the properties of the Ba ferrite 1 particles thus obtained.
（発明の効果）
かくしてこの発明によれば、粒径が０．４μｍ以下でよ
く揃い、また粒子間に焼結がな（、しかも飽和磁化が５
６ｇｍｕ／ｇ以上で保磁力が５０００ｅ〜３００００ｅ
の範囲にある磁気記録用磁性粉としてずくれた特性を持
つＢａフェライト微粒子を得ることができる。(Effects of the Invention) Thus, according to the present invention, the particle diameters are well aligned at 0.4 μm or less, and there is no sintering between the particles (and the saturation magnetization is 5 μm or less).
Coercive force is 5000e to 30000e at 6gmu/g or more
It is possible to obtain Ba ferrite fine particles having irregular characteristics as a magnetic powder for magnetic recording in the range of .
Claims (1)
ｏ＾２＾＋イオンを、Ｔｉ＾４＾＋イオンおよびＳｎ＾
４＾＋イオンの少なくとも一種と共に含有し、かつこれ
らの金属イオンの原子比をそれぞれ （Ｆｅ＋Ｃｏ＋Ｔｉ＋Ｓｎ）／Ｂａ：１０〜１３Ｃｏ／
（Ｔｉ＋Ｓｎ）：０．８〜１．２ Ｆｅ／（Ｃｏ＋Ｔｉ＋Ｓｎ）：５．８〜１５の範囲に調
整した水溶液と、アルカリ水溶液とを混合し、ｐＨ：１
０以上において沈澱物を得たのち、該沈澱物をそのｐＨ
が６〜９となるまで中和してから、融剤としてＮａまた
はＫの塩化物あるいは硫酸塩のうちから選んだ少なくと
も一種を、乾燥後の重量が全重量の５ｗｔ％以上となる
範囲において配合し、しかるのち６００〜１２００℃の
温度範囲で焼成することを特徴とする、磁気記録用Ｂａ
フェライト微粒子の製造方法。[Claims] 1. Fe^3^+ ion, Ba^2^+ ion and C
o^2^+ ions, Ti^4^+ ions and Sn^
4^+ ion, and the atomic ratio of these metal ions is (Fe+Co+Ti+Sn)/Ba:10~13Co/
(Ti+Sn): 0.8 to 1.2 Fe/(Co+Ti+Sn): An aqueous solution adjusted to a range of 5.8 to 15 and an alkaline aqueous solution were mixed, and the pH was adjusted to 1.
After obtaining a precipitate at a pH of 0 or higher, the precipitate is
Neutralize the mixture to 6 to 9, and then add at least one selected from chloride or sulfate of Na or K as a flux in a range where the weight after drying is 5 wt% or more of the total weight. and then fired at a temperature range of 600 to 1200°C.
Method for producing ferrite fine particles.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30391386A JPS63159224A (en) | 1986-12-22 | 1986-12-22 | Production of fine ba ferrite particle for magnetic recording |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP30391386A JPS63159224A (en) | 1986-12-22 | 1986-12-22 | Production of fine ba ferrite particle for magnetic recording |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63159224A true JPS63159224A (en) | 1988-07-02 |
Family
ID=17926775
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP30391386A Pending JPS63159224A (en) | 1986-12-22 | 1986-12-22 | Production of fine ba ferrite particle for magnetic recording |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63159224A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5230818A (en) * | 1991-12-20 | 1993-07-27 | Eastman Kodak Company | Coating compositions for master media for anhysteretic recording |
| JP2011093762A (en) * | 2009-10-30 | 2011-05-12 | Toda Kogyo Corp | Method for producing hexagonal ferrite particulate powder and hexagonal ferrite particulate powder, and magnetic recording medium |
-
1986
- 1986-12-22 JP JP30391386A patent/JPS63159224A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5230818A (en) * | 1991-12-20 | 1993-07-27 | Eastman Kodak Company | Coating compositions for master media for anhysteretic recording |
| JP2011093762A (en) * | 2009-10-30 | 2011-05-12 | Toda Kogyo Corp | Method for producing hexagonal ferrite particulate powder and hexagonal ferrite particulate powder, and magnetic recording medium |
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