JPS62174904A - Anticorrosive treatment of magnetic metal powder for magnetic recording - Google Patents
Anticorrosive treatment of magnetic metal powder for magnetic recordingInfo
- Publication number
- JPS62174904A JPS62174904A JP61016567A JP1656786A JPS62174904A JP S62174904 A JPS62174904 A JP S62174904A JP 61016567 A JP61016567 A JP 61016567A JP 1656786 A JP1656786 A JP 1656786A JP S62174904 A JPS62174904 A JP S62174904A
- Authority
- JP
- Japan
- Prior art keywords
- metal powder
- magnetic metal
- magnetic
- acid ester
- gallic acid
- 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
- 239000000843 powder Substances 0.000 title claims abstract description 55
- 239000002184 metal Substances 0.000 title claims abstract description 50
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 50
- LNTHITQWFMADLM-UHFFFAOYSA-N anhydrous gallic acid Natural products OC(=O)C1=CC(O)=C(O)C(O)=C1 LNTHITQWFMADLM-UHFFFAOYSA-N 0.000 claims abstract description 19
- 229940074391 gallic acid Drugs 0.000 claims abstract description 19
- 235000004515 gallic acid Nutrition 0.000 claims abstract description 19
- -1 gallic acid ester Chemical class 0.000 claims abstract description 19
- 239000003960 organic solvent Substances 0.000 claims abstract description 12
- 238000000034 method Methods 0.000 claims description 11
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 claims description 5
- 230000002265 prevention Effects 0.000 claims description 4
- 230000005415 magnetization Effects 0.000 abstract description 11
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 8
- 239000001301 oxygen Substances 0.000 abstract description 8
- 229910052760 oxygen Inorganic materials 0.000 abstract description 8
- 230000003647 oxidation Effects 0.000 abstract description 6
- 238000007254 oxidation reaction Methods 0.000 abstract description 6
- 239000002904 solvent Substances 0.000 abstract description 3
- 238000006243 chemical reaction Methods 0.000 abstract 2
- 238000007598 dipping method Methods 0.000 abstract 1
- 229920006395 saturated elastomer Polymers 0.000 abstract 1
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 6
- 230000007423 decrease Effects 0.000 description 5
- 239000003973 paint Substances 0.000 description 4
- RPWFJAMTCNSJKK-UHFFFAOYSA-N Dodecyl gallate Chemical compound CCCCCCCCCCCCOC(=O)C1=CC(O)=C(O)C(O)=C1 RPWFJAMTCNSJKK-UHFFFAOYSA-N 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 3
- 235000010386 dodecyl gallate Nutrition 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- ZTHYODDOHIVTJV-UHFFFAOYSA-N Propyl gallate Chemical compound CCCOC(=O)C1=CC(O)=C(O)C(O)=C1 ZTHYODDOHIVTJV-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- VFPFQHQNJCMNBZ-UHFFFAOYSA-N ethyl gallate Chemical compound CCOC(=O)C1=CC(O)=C(O)C(O)=C1 VFPFQHQNJCMNBZ-UHFFFAOYSA-N 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 239000006247 magnetic powder Substances 0.000 description 2
- FBSFWRHWHYMIOG-UHFFFAOYSA-N methyl 3,4,5-trihydroxybenzoate Chemical compound COC(=O)C1=CC(O)=C(O)C(O)=C1 FBSFWRHWHYMIOG-UHFFFAOYSA-N 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 239000004262 Ethyl gallate Substances 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 235000019277 ethyl gallate Nutrition 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- UCNNJGDEJXIUCC-UHFFFAOYSA-L hydroxy(oxo)iron;iron Chemical compound [Fe].O[Fe]=O.O[Fe]=O UCNNJGDEJXIUCC-UHFFFAOYSA-L 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 239000006249 magnetic particle Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- IBKQQKPQRYUGBJ-UHFFFAOYSA-N methyl gallate Natural products CC(=O)C1=CC(O)=C(O)C(O)=C1 IBKQQKPQRYUGBJ-UHFFFAOYSA-N 0.000 description 1
- BRNPAEUKZMBRLQ-UHFFFAOYSA-N octadecyl 3,4,5-trihydroxybenzoate Chemical compound CCCCCCCCCCCCCCCCCCOC(=O)C1=CC(O)=C(O)C(O)=C1 BRNPAEUKZMBRLQ-UHFFFAOYSA-N 0.000 description 1
- 235000010387 octyl gallate Nutrition 0.000 description 1
- 239000000574 octyl gallate Substances 0.000 description 1
- NRPKURNSADTHLJ-UHFFFAOYSA-N octyl gallate Chemical compound CCCCCCCCOC(=O)C1=CC(O)=C(O)C(O)=C1 NRPKURNSADTHLJ-UHFFFAOYSA-N 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- TXGSOSAONMOPDL-UHFFFAOYSA-N propan-2-yl 3,4,5-trihydroxybenzoate Chemical compound CC(C)OC(=O)C1=CC(O)=C(O)C(O)=C1 TXGSOSAONMOPDL-UHFFFAOYSA-N 0.000 description 1
- 235000010388 propyl gallate Nutrition 0.000 description 1
- 239000000473 propyl gallate Substances 0.000 description 1
- 229940075579 propyl gallate Drugs 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
- Hard Magnetic Materials (AREA)
- Paints Or Removers (AREA)
- Powder Metallurgy (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は耐蝕性のある磁気記録用磁性金属粉末を製造す
るため、同金泥粉末を防錆処理する方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for anticorrosion treatment of gold mud powder in order to produce a corrosion-resistant magnetic metal powder for magnetic recording.
磁気記録用の磁性粒子として使用される磁性金属粉末は
、金属酸化物粉末を還元して製造されている。還元して
得られたま＼の磁性金属粉末は２表面の活性が高く、空
気中で激しく酸化し、磁気特性が急激に劣化する性質を
有するため、そのま＼磁性塗料の原料として使用するこ
とはできない。そこで、磁性金属粉末の急激な酸化を防
止することを目的とした防錆処理手段が従来からいくつ
か提案されている。Magnetic metal powder used as magnetic particles for magnetic recording is produced by reducing metal oxide powder. The magnetic metal powder obtained by reduction has a high activity on the 2nd surface, and it oxidizes violently in the air, causing rapid deterioration of its magnetic properties. Therefore, it cannot be used directly as a raw material for magnetic paint. Can not. Therefore, several anti-rust treatment methods have been proposed for the purpose of preventing rapid oxidation of magnetic metal powder.
その一つは、還元して得られた直後の磁性金属粉末を、
トルエン等の有機溶剤中に浸漬した後、取り出し、有機
溶剤を徐々に蒸発させるごとによって、磁性金属粉末を
空気中の酸素と徐々に接触させる方法である。One of them is to reduce the magnetic metal powder immediately after reduction.
This is a method in which magnetic metal powder is gradually brought into contact with oxygen in the air by immersing it in an organic solvent such as toluene, taking it out, and gradually evaporating the organic solvent.
また、 Ｖｔ’ｚ性金属粉末を有限溶剤中に懸濁し。In addition, Vt'z metal powder is suspended in a finite solvent.
５０〜９０℃に加温した状態で、溶液中に酸素を含むガ
スを吹き込み、これを磁性金属粉末の表面に溶液中で接
触させる方法（日本化学会誌１９８４年魚９）等も知ら
れている。A method is also known, such as blowing oxygen-containing gas into a solution heated to 50 to 90°C and bringing it into contact with the surface of magnetic metal powder in the solution (Journal of the Chemical Society of Japan, 1984, Uo 9). .
しかし、上記の処理方法は、何れも金庫粉末の表面を徐
々に酸化させて、酸化膜で覆うことにより、磁性金属粉
末内部の急激な酸化を防止することを目的としたもので
ある。従って、処理によって磁性金属粉末の一部が非磁
性の酸化物に変わるため３個々の磁性金属粉末の磁気特
性が、酸化処理前に比べて劣化するという欠点があった
。However, the above-mentioned treatment methods all aim to prevent rapid oxidation inside the magnetic metal powder by gradually oxidizing the surface of the safe powder and covering it with an oxide film. Therefore, a part of the magnetic metal powder is converted into a non-magnetic oxide by the treatment, so that the magnetic properties of the three individual magnetic metal powders are deteriorated compared to before the oxidation treatment.
例えば、磁性金属粉末が還元して得られたま＼の鉄粉を
、上記従来の方法によって防錆処理すると、飽和磁化σ
Ｓは、１０〜４０％低下してしまう。For example, when iron powder obtained by reduction of magnetic metal powder is subjected to anti-corrosion treatment using the conventional method described above, the saturation magnetization σ
S decreases by 10 to 40%.
本発明は、上記従来の問題を解決するためになされたも
ので、その目的は、磁性金属粉末の表面に酸化膜を形成
せずに防錆処理することにより、飽和磁化σＳの低下を
防ぐことができる防錆処理方法を提供することにある。The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to prevent a decrease in saturation magnetization σS by performing rust prevention treatment on the surface of magnetic metal powder without forming an oxide film. The purpose of the present invention is to provide a rust-preventing treatment method that can prevent rust.
即ち１本発明は、没食子酸エステルを含有する有機溶剤
中に磁性金属粉末を浸漬することを特徴とする磁気記録
用磁性粉末の製造方法である。That is, one aspect of the present invention is a method for producing magnetic powder for magnetic recording, which comprises immersing magnetic metal powder in an organic solvent containing gallic acid ester.
〔作 用〕
没食子酸エステルを含有する有機溶剤中に磁性金属粉末
を浸漬すると、磁性金属粉末の表面に没食子酸エステル
が付着し１熔剤が蒸発した後もこれがそのま＼残り、上
記金属粉末の表面を覆う。この状態では、後述するよう
に、磁性金属粉末が急激に酸化さない。[Function] When magnetic metal powder is immersed in an organic solvent containing gallic acid ester, the gallic acid ester adheres to the surface of the magnetic metal powder and remains as it is even after the melt evaporates, and the above metal powder cover the surface. In this state, the magnetic metal powder is not rapidly oxidized, as will be described later.
これは、没食子酸エステルによって、磁性金属粉末の表
面が酸素と接触するのが阻止されると共に、酸素に対し
て活性の高い没食子酸エステルが、磁性金属粉末より早
く酸素と反応し。This is because the gallic acid ester prevents the surface of the magnetic metal powder from coming into contact with oxygen, and the gallic acid ester, which is highly active against oxygen, reacts with oxygen faster than the magnetic metal powder.
磁性金属粉末の酸化を防止することによるものと考えら
れる。This is thought to be due to the prevention of oxidation of the magnetic metal powder.
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）
鉄を主成分とする磁性金属粉末（長軸の平均長さ０．２
μｍ、軸比８／１．比表面積が４０ｒｒｌ／ｇ）５０ｇ
と、没食子酸エステルとして没食子酸ラウリル４ｇとを
メチルエチルケトン４００ｇの中に入れ、攪拌して懸濁
させた。この懸濁液をロータリーエバポレータに入れ、
温度を４０℃に保ったま＼、アスピレータによって減圧
し、メチルエチルケトンを蒸発させた。そのま−常温ま
で冷却した後、磁性金属粉末を空気中に取り出した。続
いて、振動試料型磁化測定器を用い。(Example 1) Magnetic metal powder mainly composed of iron (average length of long axis 0.2
μm, axial ratio 8/1. Specific surface area is 40rrl/g) 50g
and 4 g of lauryl gallate as a gallic acid ester were placed in 400 g of methyl ethyl ketone and stirred to suspend them. Put this suspension into a rotary evaporator,
While maintaining the temperature at 40°C, the pressure was reduced using an aspirator to evaporate methyl ethyl ketone. After cooling to room temperature, the magnetic metal powder was taken out into the air. Next, a vibrating sample type magnetization measuring device was used.
この粉末の飽和磁化σＳ （初期値）を測定した。The saturation magnetization σS (initial value) of this powder was measured.
その後、磁性粉末を５０℃、９０％Ｒ）Ｉの雰囲気中に
放置し、２５時間後、５０時間後、７５時間後の飽和磁
化σＳをそれぞれ測定し、その値を下表に示した。Thereafter, the magnetic powder was left in an atmosphere of 90% R)I at 50° C., and the saturation magnetization σS was measured after 25 hours, 50 hours, and 75 hours, and the values are shown in the table below.
（実施例２）
上記実施例１において、没食子酸ラウリルを４ｇから０
．５ｇに変えた以外は、実施例１と同じ方法と条件で磁
性金属粉末を処理し、これについて同様の試験行い、そ
の結果を下表に示した。(Example 2) In Example 1 above, lauryl gallate was added from 4g to 0.
．． The magnetic metal powder was treated in the same manner and under the same conditions as in Example 1, except that the amount was changed to 5 g, and the same tests were conducted on it, and the results are shown in the table below.
（実施例３） 上記実施例１において、没食子酸エステルを。(Example 3) In the above Example 1, gallic acid ester.
没食子酸ラウリル４ｇから没食子酸ステアリル２．５ｇ
に変えた以外は、実施例１と同じ方法と条件で磁性金属
粉末を処理し、これについて同様の試験行い２その結果
を下表に示した。4g of lauryl gallate to 2.5g of stearyl gallate
The magnetic metal powder was treated in the same manner and under the same conditions as in Example 1, except that the results were changed to 2 and the results are shown in the table below.
（比較例）
上記実施例１において、有機溶剤に没食子酸エステルを
加えず、これ以外は、実施例１と同じ方法と条件で磁性
金属粉末を処理し、これについて同様の試験行い、その
結果を下表に示した。(Comparative Example) In Example 1 above, magnetic metal powder was treated in the same manner and under the same conditions as in Example 1, except that no gallic acid ester was added to the organic solvent, and the same tests were conducted on the powder. Shown in the table below.
上表から明らかなように１本発明の防錆処理方法を施し
た各実施例の磁性金属粉末の飽和磁化σＳは、従来の処
理方法を施して得られた比較例の磁性金属粉末に比べて
、飽和磁化σＳの初期値が１４〜１９％程高い。さらに
、温度５０℃。As is clear from the above table, the saturation magnetization σS of the magnetic metal powder of each example treated with the rust prevention treatment method of the present invention is higher than that of the magnetic metal powder of the comparative example obtained by the conventional treatment method. , the initial value of saturation magnetization σS is about 14 to 19% higher. Furthermore, the temperature was 50°C.
湿度９０％ｌ？Ｈの雰囲気の中に放置したときの酸化の
進行が緩やかで、飽和磁化σＳの低下も微少である。Humidity 90%l? When left in an H atmosphere, oxidation progresses slowly and the saturation magnetization σS decreases only slightly.
没食子酸エステルとしては、上記実施例において使用し
たちの＼他、没食子酸メチル、没食子酸エチル、没食子
酸プロピル、没食子酸イソプロピル、没食子酸オクチル
等を使用することができる。As the gallic acid ester, in addition to those used in the above examples, methyl gallate, ethyl gallate, propyl gallate, isopropyl gallate, octyl gallate, etc. can be used.
有機溶剤中に含ませる没食子酸エステルの量は、磁性金
属粉末に対して、０．５〜８重量％の割合が好ましい。The amount of gallic acid ester contained in the organic solvent is preferably 0.5 to 8% by weight based on the magnetic metal powder.
これは、没食子酸エステルが磁性金属粉末に対して、０
．５ｆｆｉ量％より少ないと。This means that gallic acid ester has a zero resistance to magnetic metal powder.
．． If it is less than 5ffi amount%.
酸化防止効果が薄れ、８重量％を超えて含ませると、磁
性金属粉末から作られた磁性塗料の分散性が悪くなり、
磁気記録媒体の角形比が低下する。The antioxidant effect will be weakened, and if it is included in an amount exceeding 8% by weight, the dispersibility of magnetic paint made from magnetic metal powder will deteriorate.
The squareness ratio of the magnetic recording medium decreases.
なお、磁性金属粉末から磁性塗料を作るときは、上記各
実施例のように、有機溶剤を蒸発させずに、これをバイ
ンダの溶剤としてそのま＼使用することもできる。即ち
、没食子酸エステルを含む有機溶剤の中に磁性金属粉末
を１懸濁させたま＼、この中にバインダの樹脂成分等を
直接加えて混練することにより、磁性塗料を作ることが
できる。When making a magnetic paint from magnetic metal powder, it is also possible to use the organic solvent as it is as a binder solvent without evaporating the organic solvent, as in each of the above embodiments. That is, a magnetic paint can be made by suspending magnetic metal powder in an organic solvent containing gallic acid ester, and directly adding a binder resin component and kneading the suspension.
以上説明した通り１本発明によれば、磁性金属粉末の飽
和磁化σＳを、従来方法で防錆処理したものより高くす
ることができる。さらに。As explained above, according to the present invention, the saturation magnetization σS of the magnetic metal powder can be made higher than that of the magnetic metal powder subjected to antirust treatment using the conventional method. moreover.
耐蝕性も優れ、飽和磁化σＳが低下しにくい磁気記録用
磁性金属粉末を提供することができる効果がある。This has the effect of providing a magnetic metal powder for magnetic recording which has excellent corrosion resistance and whose saturation magnetization σS does not easily decrease.
発明者北折 典之 同 上後藤 晃Inventor Noriyuki Kitaori Same as Akira Kamigoto
Claims (1)
いて、没食子酸エステルを含有する有機溶剤中に磁性金
属粉末を浸漬することを特徴とする磁気記録用磁性金属
粉末の防錆処理方法。 ２、没食子酸エステルが、磁性金属粉に対して０．５〜
８重量％の割合である特許請求の範囲第１項記載の磁気
記録用磁性金属粉末の防錆処理方法。[Scope of Claims] 1. A method for anticorrosion treatment of magnetic metal powder for magnetic recording, which comprises immersing the magnetic metal powder in an organic solvent containing gallic acid ester. Rust prevention treatment method. 2. Gallic acid ester is 0.5 to magnetic metal powder
A method for rust-proofing magnetic metal powder for magnetic recording according to claim 1, wherein the proportion is 8% by weight.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61016567A JPS62174904A (en) | 1986-01-28 | 1986-01-28 | Anticorrosive treatment of magnetic metal powder for magnetic recording |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61016567A JPS62174904A (en) | 1986-01-28 | 1986-01-28 | Anticorrosive treatment of magnetic metal powder for magnetic recording |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62174904A true JPS62174904A (en) | 1987-07-31 |
| JPH0523483B2 JPH0523483B2 (en) | 1993-04-02 |
Family
ID=11919864
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61016567A Granted JPS62174904A (en) | 1986-01-28 | 1986-01-28 | Anticorrosive treatment of magnetic metal powder for magnetic recording |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62174904A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009221505A (en) * | 2008-03-14 | 2009-10-01 | Dowa Electronics Materials Co Ltd | Silver nanoparticle coated with gallic acid or its derivative |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6150213A (en) * | 1984-08-16 | 1986-03-12 | Matsushita Electric Ind Co Ltd | Magnetic recording medium |
-
1986
- 1986-01-28 JP JP61016567A patent/JPS62174904A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6150213A (en) * | 1984-08-16 | 1986-03-12 | Matsushita Electric Ind Co Ltd | Magnetic recording medium |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009221505A (en) * | 2008-03-14 | 2009-10-01 | Dowa Electronics Materials Co Ltd | Silver nanoparticle coated with gallic acid or its derivative |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0523483B2 (en) | 1993-04-02 |
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