JPS62197323A - Production of magnetic powder - Google Patents
Production of magnetic powderInfo
- Publication number
- JPS62197323A JPS62197323A JP61036888A JP3688886A JPS62197323A JP S62197323 A JPS62197323 A JP S62197323A JP 61036888 A JP61036888 A JP 61036888A JP 3688886 A JP3688886 A JP 3688886A JP S62197323 A JPS62197323 A JP S62197323A
- Authority
- JP
- Japan
- Prior art keywords
- iron oxide
- magnetic powder
- powder
- cobalt
- oxide magnetic
- 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
- 239000006247 magnetic powder Substances 0.000 title claims abstract description 46
- 238000004519 manufacturing process Methods 0.000 title claims description 3
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims abstract description 100
- 239000002245 particle Substances 0.000 claims abstract description 19
- 239000000843 powder Substances 0.000 claims abstract description 12
- 150000001868 cobalt Chemical class 0.000 claims abstract description 11
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 claims abstract description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000003513 alkali Substances 0.000 claims abstract description 7
- 238000010438 heat treatment Methods 0.000 claims abstract description 5
- 239000010941 cobalt Substances 0.000 claims description 33
- 229910017052 cobalt Inorganic materials 0.000 claims description 33
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 32
- 239000007864 aqueous solution Substances 0.000 claims description 5
- 238000001035 drying Methods 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 3
- 238000010298 pulverizing process Methods 0.000 claims description 2
- 238000005406 washing Methods 0.000 claims description 2
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 230000005415 magnetization Effects 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 4
- 239000004570 mortar (masonry) Substances 0.000 description 4
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical class [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 2
- 229940044175 cobalt sulfate Drugs 0.000 description 2
- 229910000361 cobalt sulfate Inorganic materials 0.000 description 2
- KTVIXTQDYHMGHF-UHFFFAOYSA-L cobalt(2+) sulfate Chemical compound [Co+2].[O-]S([O-])(=O)=O KTVIXTQDYHMGHF-UHFFFAOYSA-L 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- POULHZVOKOAJMA-UHFFFAOYSA-N dodecanoic acid Chemical compound CCCCCCCCCCCC(O)=O POULHZVOKOAJMA-UHFFFAOYSA-N 0.000 description 2
- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 2
- 235000003891 ferrous sulphate Nutrition 0.000 description 2
- 239000011790 ferrous sulphate Substances 0.000 description 2
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000003973 paint Substances 0.000 description 2
- 235000011121 sodium hydroxide Nutrition 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 229920002554 vinyl polymer Polymers 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 1
- 238000004438 BET method Methods 0.000 description 1
- JOYRKODLDBILNP-UHFFFAOYSA-N Ethyl urethane Chemical compound CCOC(N)=O JOYRKODLDBILNP-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 239000005639 Lauric acid Substances 0.000 description 1
- NTIZESTWPVYFNL-UHFFFAOYSA-N Methyl isobutyl ketone Chemical compound CC(C)CC(C)=O NTIZESTWPVYFNL-UHFFFAOYSA-N 0.000 description 1
- UIHCLUNTQKBZGK-UHFFFAOYSA-N Methyl isobutyl ketone Natural products CCC(C)C(C)=O UIHCLUNTQKBZGK-UHFFFAOYSA-N 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- GVPFVAHMJGGAJG-UHFFFAOYSA-L cobalt dichloride Chemical compound [Cl-].[Cl-].[Co+2] GVPFVAHMJGGAJG-UHFFFAOYSA-L 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229960002089 ferrous chloride Drugs 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- NMCUIPGRVMDVDB-UHFFFAOYSA-L iron dichloride Chemical compound Cl[Fe]Cl NMCUIPGRVMDVDB-UHFFFAOYSA-L 0.000 description 1
- 239000012948 isocyanate Substances 0.000 description 1
- -1 isocyanate compound Chemical class 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920002635 polyurethane Polymers 0.000 description 1
- 239000004814 polyurethane Substances 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- 229910006297 γ-Fe2O3 Inorganic materials 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〕
この発明は磁気記録媒体の記録素子として好適なコバル
ト含有酸化鉄磁性粉末の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing cobalt-containing iron oxide magnetic powder suitable as a recording element of a magnetic recording medium.
コバルトを含有する酸化鉄磁性粉末は、従来の磁気記録
媒体の記録素子として汎用されている酸化鉄磁性粉末に
比べ高保磁力を有するため、高性能磁気記録媒体の記録
素子として有用である。Iron oxide magnetic powder containing cobalt has a higher coercive force than iron oxide magnetic powder commonly used as a recording element in conventional magnetic recording media, and is therefore useful as a recording element in high-performance magnetic recording media.
このようなコバルト含有酸化鉄磁性粉末の製造方法はこ
れまで種々提案されており、その代表的な方法の１つと
して、酸化鉄磁性粉末をコバルト塩および第一鉄塩を含
む水溶液中に分散させ、これにアルカリ水溶液を加えて
酸化鉄磁性粉末の粒子表面にコバルトを含む酸化鉄層を
形成させるものがある。（特開昭５５−５６０１９号）
〔発明が解決しようとする問題点〕
ところが、この従来の方法で得られるコバルト含有酸化
鉄磁性粉末は、転写特性に優れるものの消去特性が未だ
充分に良好でなく、特に、記録密度を向上させ、ノイズ
を低減するため、この種のコバルト含有酸化鉄磁性粉末
を微粒子化し、保磁力を向上させようとすると、消去特
性が劣化するという難点がある。Various methods for producing such cobalt-containing iron oxide magnetic powder have been proposed, and one typical method involves dispersing iron oxide magnetic powder in an aqueous solution containing a cobalt salt and a ferrous salt. There is a method in which an aqueous alkaline solution is added to this to form an iron oxide layer containing cobalt on the surface of the iron oxide magnetic powder particles. (Unexamined Japanese Patent Publication No. 55-56019)
[Problems to be Solved by the Invention] However, although the cobalt-containing iron oxide magnetic powder obtained by this conventional method has excellent transfer characteristics, its erasing characteristics are still not sufficiently good. In order to reduce noise, if this type of cobalt-containing iron oxide magnetic powder is made into fine particles and an attempt is made to improve the coercive force, there is a problem in that the erasing characteristics deteriorate.
この発明は、かかる現状に鑑み鋭意研究を重ねた結果な
されたもので、酸化鉄磁性粉末を、コバルト塩および第
一鉄塩とアルカリとを含む水溶液中で反応させて酸化鉄
磁性粉末の粒子表面にコバルトを含む酸化鉄層を形成し
、次いで、これを水洗、濾過、乾燥した後、得られた粉
末を粉砕してその粒度を均一にし、しかる後、加熱処理
することによって、コバルト含有酸化鉄磁性粉末の消去
特性を改善し、このコバルト含有酸化鉄磁性粉末を使用
して得られる磁気記録媒体の消去特性を充分に向上させ
たものである。This invention was made as a result of extensive research in view of the current situation, and was made by reacting iron oxide magnetic powder in an aqueous solution containing cobalt salts, ferrous salts, and alkali to improve the particle surface of the iron oxide magnetic powder. A cobalt-containing iron oxide layer is formed on the surface, which is then washed with water, filtered, and dried.The resulting powder is pulverized to make the particle size uniform, and then heat-treated to form a cobalt-containing iron oxide layer. The erasing properties of the magnetic powder are improved, and the erasing properties of the magnetic recording medium obtained using this cobalt-containing iron oxide magnetic powder are sufficiently improved.
この発明において、出発原料として用いる酸化鉄磁性粉
末は、たとえば、針状の７−Ｆｅ２Ｏ３粉末、Ｆｅ３Ｏ
４粉末およびｒ−Ｆｅ２０３を水素気流中で部分還元す
ることによって得られるγ−Ｆｅ２Ｏ３とＦｅ３Ｏ４と
の中間の酸化状態の酸化鉄磁性粉末などが好適なものと
して使用される。In this invention, the iron oxide magnetic powder used as a starting material is, for example, acicular 7-Fe2O3 powder, Fe3O
Iron oxide magnetic powder having an oxidation state intermediate between γ-Fe2O3 and Fe3O4, which is obtained by partially reducing r-Fe203 and r-Fe203 powder in a hydrogen stream, is preferably used.
これらの酸化鉄磁性粉末は、コバルト塩および第一鉄塩
とアルカリとを含む水溶液中で反応させて酸化鉄磁性粉
末の粒子表面にコバルトを含む酸化鉄層を形成し、次い
で、これを水洗、濾過、乾燥した後、得られた粉末を粉
砕してその粒度を均一にし、しかる後、加熱処理するの
が好ましく、このように粒度を均一にした後、加熱処理
すると熱が粉末全体に均一に伝わって、コバルトを均一
に含む酸化鉄層が良好に形成され、保磁力分布が非常に
良好で消去特性に優れたコバルト含有酸化鉄磁性粉末が
得られ、このコバルト含有酸化鉄磁性粉末を使用して得
られる磁気記録媒体の消去特性が充分に向上される。These iron oxide magnetic powders are reacted in an aqueous solution containing a cobalt salt, a ferrous salt, and an alkali to form an iron oxide layer containing cobalt on the particle surface of the iron oxide magnetic powder, which is then washed with water, After filtration and drying, it is preferable to crush the resulting powder to make the particle size uniform, and then heat treat it. As a result, a cobalt-containing iron oxide magnetic powder with an excellent formation of an iron oxide layer containing cobalt uniformly, a very good coercive force distribution, and excellent erasing properties was obtained. The erasing characteristics of the magnetic recording medium obtained by this method are sufficiently improved.
このような粒子表面にコバルトを含む酸化鉄層を形成し
た酸化鉄磁性粉末の破砕は、乳鉢等を使用して行われ、
粒度は、次の加熱処理工程での熱の伝達が可及的に均一
に行われるように、１０〜５００メツシユの篩を通過で
きる程度に微細にし、かつ均一にするのが好ましい。Such iron oxide magnetic powder, which has an iron oxide layer containing cobalt formed on the particle surface, is crushed using a mortar or the like.
The particle size is preferably fine enough to pass through a 10 to 500 mesh sieve and uniform so that heat transfer in the next heat treatment step is as uniform as possible.
また、コバルトを含む酸化鉄層を形成した酸化鉄磁性粉
末粒度を均一にした後の加熱処理は、１８０℃より高く
てはコバルトが固溶するため１８０℃以下の温度で行う
のが好ましい。なお、この加熱処理は非酸化性雰囲気中
で行うと、本発明の効果がいっそう顕著となる。Further, the heat treatment after uniformizing the grain size of the iron oxide magnetic powder forming the cobalt-containing iron oxide layer is preferably carried out at a temperature of 180° C. or lower, since cobalt dissolves in solid solution at temperatures higher than 180° C. Note that the effect of the present invention becomes even more remarkable when this heat treatment is performed in a non-oxidizing atmosphere.
コバルト塩としては塩化コバルト、硫酸コバルトなどが
好適なものとして使用され、第一鉄塩としては塩化第一
鉄、硫酸第一鉄などが好ましく使用される。Cobalt salts such as cobalt chloride and cobalt sulfate are preferably used, and ferrous salts such as ferrous chloride and ferrous sulfate are preferably used.
またアルカリとしては、通常、苛性ソーダが用いられ、
その好適な配合量は、コバルト塩と第一鉄塩との総量に
対して当量以上とするのが好ましい。Caustic soda is usually used as the alkali.
The suitable amount of the cobalt salt and the ferrous salt is preferably equal to or more than the total amount of the cobalt salt and the ferrous salt.
以上のように、酸化鉄磁性粉末を、コバルト塩および第
一鉄塩とアルカリとを含む水溶液中で反応させて酸化鉄
磁性粉末の粒子表面にコバルトを含む酸化鉄層を形成し
、次いで、これを水洗、濾過、乾燥した後、得られた粉
末を粉砕してその粒度を均一にし、しかる後、加熱処理
すると、−粒子一粒子に熱が均一に作用するため、保磁
力分布が良好で消去特性に優れたコバルト含有酸化鉄磁
性粉末が得られ、この磁性粉末を使用して得られる磁気
記録媒体の消去特性が充分に向上される。As described above, iron oxide magnetic powder is reacted in an aqueous solution containing a cobalt salt, a ferrous salt, and an alkali to form an iron oxide layer containing cobalt on the particle surface of the iron oxide magnetic powder. After washing with water, filtering, and drying, the obtained powder is crushed to make the particle size uniform, and then heat-treated.- Heat acts uniformly on each particle, so the coercive force distribution is good and erased. A cobalt-containing iron oxide magnetic powder with excellent properties is obtained, and the erasing properties of a magnetic recording medium obtained using this magnetic powder are sufficiently improved.
次に、この発明の実施例について説明する。 Next, embodiments of the invention will be described.
実施例１
長軸径０，３μｍ、軸比８、ＢＥＴ法による比表面積３
２．Ｏｒｄ／ｇ 、保磁力３５０エルステツド、飽和磁
化量７５．１ ｅｍｕ ７ｇの針状ｒ−Ｆｅ２０３粉末
１００ｆｆｉ量部を、水５００重量部に分散させ、これ
に硫酸コバルト（Ｃｏ ＳＯ４・７ Ｈ２０） １４
重量部と硫酸第１鉄（Ｆ ｅ ＳＯ４・７ Ｈ２０）４
２重量部とを水２００重量部に溶解した溶液を添加した
。次いで、水酸化ナトリウム１００重量部を水３００重
量部に溶解させた溶液を添加し、６０℃の温度で３時間
攪拌して反応させた。次いで、これを水洗、濾過し、空
気中にて８０℃の温度で１０時間乾燥した。このように
して得られた磁性粉末の保磁力は６７０エルステツドで
飽和磁化量は？？、８ ｅｍｕ ７ｇであった。次ぎに
、このようにして得られた磁性粉末を乳鉢で粉砕し、１
０００μｍ目の篩（Ｊ Ｉ Ｓ １６メツシユ）にかけ
て、この篩を通過した試料を分級し、これを窒素ガス中
１２０℃の温度で２時間加熱処理し、室温まで徐冷して
コバルトを含む酸化鉄層を粒子表面に形成させた磁性粉
末を得た。このようにして得られたコバルト含有酸化鉄
磁性粉末は、保磁力が６９０エルステツドで飽和磁化量
は？７．８ｅｍｕ ／ ｇであった。またコバルト含有
量は２．６Ｎ量％であった。Example 1 Major axis diameter 0.3 μm, axial ratio 8, specific surface area 3 by BET method
2. Ord/g, coercive force 350 oersted, saturation magnetization amount 75.1 emu 100 parts of acicular r-Fe203 powder of 7 g was dispersed in 500 parts by weight of water, and cobalt sulfate (Co SO4.7 H20) 14
Parts by weight and ferrous sulfate (F e SO4.7 H20) 4
A solution prepared by dissolving 2 parts by weight of 2 parts by weight in 200 parts by weight of water was added. Next, a solution prepared by dissolving 100 parts by weight of sodium hydroxide in 300 parts by weight of water was added, and the mixture was stirred at a temperature of 60° C. for 3 hours to react. Next, this was washed with water, filtered, and dried in air at a temperature of 80° C. for 10 hours. The magnetic powder thus obtained has a coercive force of 670 oersted and what is its saturation magnetization? ? , 8 emu 7g. Next, the magnetic powder obtained in this way was ground in a mortar, and 1
The sample that passed through this sieve was classified by passing it through a 000 μm sieve (JIS 16 mesh), heat treated in nitrogen gas at a temperature of 120°C for 2 hours, and slowly cooled to room temperature to extract iron oxide containing cobalt. Magnetic powder with a layer formed on the particle surface was obtained. The cobalt-containing iron oxide magnetic powder thus obtained has a coercive force of 690 Oersteds and a saturation magnetization amount? It was 7.8 emu/g. Further, the cobalt content was 2.6N%.
実施例２
実施例１において、乳鉢で粉砕後、１０５μｍ目（ＪＩ
Ｓ１４５メソシュ）の篩を通過し、４４μｍ目（ＪＩＳ
３５０メツシュ）を通過しないものに分級し、この試料
を使用した以外は実施例１と同様にしてコバルトを含む
酸化鉄層を粒子表面に形成させた磁性粉末を得た。この
ようにして得られたコバルト含有酸化鉄磁性粉末は、保
磁力が６８５エルステツドで飽和磁化量は７Ｂ、１ｅｍ
ｕ ／ ｇであった。またコバルト含有量は２．６重量
％であった。Example 2 In Example 1, after grinding in a mortar, the 105 μm
S145 mesh) passed through a sieve of 44 μm (JIS
A magnetic powder having an iron oxide layer containing cobalt formed on the particle surface was obtained in the same manner as in Example 1 except that this sample was used. The cobalt-containing iron oxide magnetic powder thus obtained has a coercive force of 685 oersteds, a saturation magnetization of 7 B, and 1 em.
It was u/g. Further, the cobalt content was 2.6% by weight.
比較例１
実施例１において、乳鉢で粉砕後、分級操作を省いた以
外は実施例１と同様にしてコバルトを含む酸化鉄層を粒
子表面に形成させた磁性粉末を得た。このようにして得
られたコバルト含有酸化鉄磁性粉末には、５０００μｍ
程度の粗粒が多く含まれていた。またこのようにして得
られたコバルト含有酸化鉄磁性粉末は、保磁力が６９２
エルステツドで飽和磁化量は７８．２ｅｍｕ ／ ｇで
あった。またコバルト含有量は２．６重量％であった。Comparative Example 1 Magnetic powder in which an iron oxide layer containing cobalt was formed on the particle surface was obtained in the same manner as in Example 1, except that the classification operation after pulverization in a mortar was omitted. The cobalt-containing iron oxide magnetic powder thus obtained has a diameter of 5000 μm.
It contained many coarse grains. The cobalt-containing iron oxide magnetic powder thus obtained has a coercive force of 692.
The saturation magnetization amount in Oersted was 78.2 emu/g. Further, the cobalt content was 2.6% by weight.
次に、上記実施例１．２および比較例１で得られたコバ
ルト含有酸化鉄磁性粉末を用いて、下記の配合組成によ
り磁性塗料を調製し、この塗料を１２μｍ厚のポリエス
テルベースフィルム上に乾燥厚が５μｍとなるように塗
布、乾燥して磁気テープをつくった。Next, using the cobalt-containing iron oxide magnetic powder obtained in Example 1.2 and Comparative Example 1 above, a magnetic paint was prepared according to the formulation shown below, and this paint was dried on a 12 μm thick polyester base film. A magnetic tape was prepared by coating and drying to a thickness of 5 μm.
コバルト含有酸化鉄磁性粉末 １００重量部ＶＡＧＨ
（ｔｌ、ｃ、ｃ社製、塩化ビ １３〃ニル−酢酸ビニ
ル−ビニルア
ルコール共重合体）
Ｔ５２０１（大日本インキ化学 １０〃工業社製、ウ
レタンプレポリ
マー）
コロネートしく日本ポリウレ ２ 〃タン工業社
製、三官能性細分
重量イソシアネート化合物）
ラウリン酸 ２ 〃メチルイソ
ブチルケトン ７５〃トルエン
７５〃このようにして得られた各磁気テープ
について、保磁力および消去特性を調べた。消去特性は
、ＩＫＨｚでの元信号レベルと、消去後信号レベルとの
差を測定して示した。なお、消去電流はハイポジション
カセットチーブの規定消去電流値を用いた。Cobalt-containing iron oxide magnetic powder 100 parts by weight VAGH
(manufactured by TL, C, C, vinyl chloride-vinyl acetate-vinyl alcohol copolymer) T5201 (manufactured by Dainippon Ink Chemical Co., Ltd. 10, urethane prepolymer) Coronate Nippon Polyurethane 2, manufactured by Tan Kogyo Co., Ltd. , trifunctional subdivided weight isocyanate compound) Lauric acid 2 Methyl isobutyl ketone 75 Toluene
75. The coercive force and erasing characteristics of each of the magnetic tapes thus obtained were examined. The erasing characteristics were shown by measuring the difference between the original signal level at IKHz and the signal level after erasing. Note that the specified erase current value of the high position cassette chip was used as the erase current.
下表はその結果である。The table below shows the results.
Ｃ発明の効果〕
上表から明らかなように、この発明で得られたコバルト
含有酸化鉄磁性粉末を使用して得られた磁気テープ（実
施例１および２）は、従来の方法で得られたコバルト含
有酸化鉄磁性粉末を使用して得られた磁気テープ（比較
例１）に比し、消去特性がよく、このことから、この発
明の方法で得られるコバルト含有酸化鉄磁性粉末を使用
して得られる磁気記録媒体は消去特性に優れていること
がわかる。C Effects of the Invention] As is clear from the above table, the magnetic tapes obtained using the cobalt-containing iron oxide magnetic powder obtained by the present invention (Examples 1 and 2) were as good as those obtained by the conventional method. Compared to the magnetic tape obtained using the cobalt-containing iron oxide magnetic powder (Comparative Example 1), the erasing properties are better, and from this, the cobalt-containing iron oxide magnetic powder obtained by the method of the present invention is used. It can be seen that the obtained magnetic recording medium has excellent erasing characteristics.
Claims (1)
ルカリとを含む水溶液中で反応させて酸化鉄磁性粉末の
粒子表面にコバルトを含む酸化鉄層を形成し、次いで、
これを水洗、濾過、乾燥した後、得られた粉末を粉砕し
てその粒度を均一にし、しかる後、加熱処理することを
特徴とする磁性粉末の製造方法1. The iron oxide magnetic powder is reacted in an aqueous solution containing a cobalt salt, a ferrous salt, and an alkali to form an iron oxide layer containing cobalt on the particle surface of the iron oxide magnetic powder, and then,
A method for producing magnetic powder, which comprises washing the powder with water, filtering it, drying it, pulverizing the obtained powder to make the particle size uniform, and then subjecting it to heat treatment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61036888A JPS62197323A (en) | 1986-02-20 | 1986-02-20 | Production of magnetic powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61036888A JPS62197323A (en) | 1986-02-20 | 1986-02-20 | Production of magnetic powder |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS62197323A true JPS62197323A (en) | 1987-09-01 |
Family
ID=12482315
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61036888A Pending JPS62197323A (en) | 1986-02-20 | 1986-02-20 | Production of magnetic powder |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62197323A (en) |
-
1986
- 1986-02-20 JP JP61036888A patent/JPS62197323A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH0212004B2 (en) | ||
| US4296149A (en) | Manufacture of acicular cobalt-containing magnetic iron oxide | |
| JP5711086B2 (en) | Magnetic powder for magnetic recording, method for producing the same, and magnetic recording medium | |
| JPS62287604A (en) | Magnetic material and manufacture of the same and magnetic recording medium | |
| JPS60255628A (en) | Fine powder of ba ferrite plate particle for magnetic recording use and its preparation | |
| JPS62197323A (en) | Production of magnetic powder | |
| EP0857693B1 (en) | Processes for producing hydrated iron oxide and ferromagnetic iron oxide | |
| JP5293946B2 (en) | Method for producing nonmagnetic particle powder for nonmagnetic underlayer of magnetic recording medium, and magnetic recording medium | |
| KR0169491B1 (en) | Acicular ferromagnetic iron oxide particles and process for producing the same | |
| JPS6242858B2 (en) | ||
| KR0125939B1 (en) | Process for producing magnetic iron oxide particles for magnetic recording | |
| JPH07192248A (en) | Undercoat layer for magnetic recording medium | |
| JP2843124B2 (en) | Method for producing metal magnetic powder | |
| JP2945458B2 (en) | Acicular ferromagnetic iron oxide powder and method for producing the same | |
| JPS58161706A (en) | Production of ferromagnetic powder | |
| JPS58161710A (en) | Production of ferromagnetic powder | |
| JPH06263449A (en) | Non-magnetic blackish brown hydrated iron oxide particle powder, production thereof and substrate for magnetic recording medium using the powder | |
| JPH0766020A (en) | Non-magnetic blackish-brown hydrate iron-oxide particle powder and manufacture of powder and foundation layer for magnetic recording medium using powder | |
| JPS58161703A (en) | Production of ferromagnetic powder | |
| JP2945457B2 (en) | Acicular magnetic iron oxide powder and method for producing the same | |
| JPS5946281B2 (en) | Method for producing acicular Fe-Co alloy magnetic particle powder | |
| JPS6140007A (en) | Manufacture of plate shaped ba ferrite fine particle powder for magnetic recording | |
| JPS6364920A (en) | Production of magnetic powder for magnetic recording | |
| JPH0568008B2 (en) | ||
| JPH0545529B2 (en) |