JPH06104574B2 - Coating film type magnetic powder for magnetic recording - Google Patents
Coating film type magnetic powder for magnetic recordingInfo
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- JPH06104574B2 JPH06104574B2 JP60262139A JP26213985A JPH06104574B2 JP H06104574 B2 JPH06104574 B2 JP H06104574B2 JP 60262139 A JP60262139 A JP 60262139A JP 26213985 A JP26213985 A JP 26213985A JP H06104574 B2 JPH06104574 B2 JP H06104574B2
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- magnetic powder
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- coating film
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Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は塗布膜タイプの磁気記録用磁性粉に関し、更に
詳しくは、塗布膜タイプの高密度磁気記録媒体用に適用
する微細な粒子からなる六方晶系フェライト磁性粉に関
するものである。Description: TECHNICAL FIELD The present invention relates to a coating film type magnetic powder for magnetic recording, and more specifically, it comprises fine particles applied to a coating film type high density magnetic recording medium. The present invention relates to hexagonal ferrite magnetic powder.
（従来の技術） 近年、磁気記録に対する高密度化の要求に伴い磁気記録
媒体の厚味方向に磁界を記録する垂直磁気記録方式が注
目されている。このような垂直磁気記録方式において使
用される磁性材料は記録媒体表面に垂直な方向に磁化容
易軸を有することが必要である。(Prior Art) In recent years, along with a demand for higher density in magnetic recording, a perpendicular magnetic recording method for recording a magnetic field in a thickness direction of a magnetic recording medium has been attracting attention. The magnetic material used in such a perpendicular magnetic recording system must have an easy axis of magnetization in a direction perpendicular to the surface of the recording medium.
六方晶系で一軸磁化異方性を有するフェライト、例えば
Baフェライト（BaFe12O19）は六角板状の結晶であっ
て、板面に垂直な方向に磁化容易軸を有しており、塗布
膜タイプの垂直磁気記録用磁性材料として上記の要件を
満足するものである。該磁性材料としては適度な保磁力
（Hc,通常300〜2000Oe程度）とできるだけ大きな飽和磁
化（σｓ）を有している事、及び記録波長の関係から、
磁性粉の平均粒子径は0.3μｍ以下であることが必要で
ある。Hexagonal ferrite with uniaxial magnetization anisotropy, for example
Ba ferrite (BaFe 12 O 19 ) is a hexagonal plate-shaped crystal that has an easy axis of magnetization in the direction perpendicular to the plate surface and satisfies the above requirements as a coating film type magnetic material for perpendicular magnetic recording. To do. As the magnetic material, it has an appropriate coercive force (Hc, usually about 300 to 2000 Oe) and a saturation magnetization (σs) as large as possible, and from the relationship of the recording wavelength,
The average particle diameter of the magnetic powder needs to be 0.3 μm or less.
ところで、Baフェライトは保磁力が5000Oe以上であり、
このままでは磁気記録用磁性材料としては大きすぎるの
で、Feの一部をCo及びTiで置換して、保磁力を低下させ
る方法が提案されている（例えば特開昭55−86103号公
報，特開昭59−175707号公報,IEEE Trans.on Magn.,MAG
−18,16（1982）P.1122など）。By the way, Ba ferrite has a coercive force of 5000 Oe or more,
As it is, it is too large as a magnetic material for magnetic recording. Therefore, a method of substituting a part of Fe with Co and Ti to reduce the coercive force has been proposed (for example, JP-A-55-86103, JP-A-55-86103). Sho 59-175707, IEEE Trans.on Magn., MAG
-18,16 (1982) P.1122).
（発明が解決しようとする問題点） ところで、Feの一部をCo及びTiで置換した公知の磁性粉
は、構成元素の組成比がほぼ同一であっても、磁性粉の
製造方法や製造条件が異なると、保磁力や飽和磁化は、
表１に示すとうり、全くまちまちである。このことは、
Feの一部をCo及びTiで置換しただけでは、保磁力の制御
はまだ不充分であることを示している。(Problems to be solved by the invention) By the way, in the known magnetic powder in which a part of Fe is replaced by Co and Ti, even if the composition ratio of the constituent elements is almost the same, the manufacturing method and manufacturing conditions of the magnetic powder , The coercive force and saturation magnetization are
As shown in Table 1, it is quite different. This is
It is shown that the coercive force is still insufficiently controlled only by substituting a part of Fe with Co and Ti.
（問題点を解決するための手段） 本発明者等は、従来のこの様な欠点のない塗布膜タイプ
の垂直磁気記録用磁性粉を開発すべく鋭意検討した結
果、従来のCo及びTiの他に更に特定の金属を加える事が
効果的であることを見出し、本発明を完成するに至っ
た。 (Means for Solving Problems) The inventors of the present invention have made earnest studies to develop a coating film type magnetic powder for perpendicular magnetic recording which does not have such a conventional defect. It was found that it is effective to further add a specific metal to, and the present invention has been completed.
すなわち、本発明により一般組成式 FeaCobTicMI dMII eOf （ここでMIはBa,Sr,Ca及びPbから選択される少なくとも
一種の金属元素を表わし、MIIはCd,Ag,Te,P,As,Bi及びS
iから選択される少なくとも一種の金属元素を表わし、
a,b,c,d,e及びｆはそれぞれFe,Co,Ti,MI，MII及びＯの
原子数であり、ａは８〜11.8、ｂは0.05〜2.0,cは0.05
〜2.0,dは0.5〜3.0及びｅは0.01〜2.0の値をとり、ｆは
他の元素の原子価を満足する酸素の原子数を表わす。）
で表わされ、且つ平均粒子径0.01〜0.3μｍであること
を特徴とする塗布膜タイプの磁気記録用磁性粉が提供さ
れる。That is, according to the present invention, the general composition formula Fe a Co b Ti c M I d M II e O f (where M I represents at least one metal element selected from Ba, Sr, Ca and Pb, M II is Cd, Ag, Te, P, As, Bi and S
represents at least one metal element selected from i,
a, b, c, d, e and f are the numbers of Fe, Co, Ti, M I , M II and O atoms, respectively, a is 8 to 11.8, b is 0.05 to 2.0, and c is 0.05.
.About.2.0, d is 0.5 to 3.0 and e is 0.01 to 2.0, and f is the number of oxygen atoms satisfying the valences of other elements. )
And an average particle diameter of 0.01 to 0.3 μm, a coating film type magnetic powder for magnetic recording is provided.
本発明においては、磁性粉の各成分元素の原子数ａ〜ｅ
が上記の数値範囲内にあることが必要で、この範囲外で
は磁気記録用磁性粉に適した保磁力や飽和磁化を持った
磁性粉は得られ難い。In the present invention, the number of atoms a to e of each component element of the magnetic powder is
Must be within the above numerical range, and outside this range, it is difficult to obtain a magnetic powder having a coercive force and saturation magnetization suitable for magnetic powder for magnetic recording.
好ましい磁性粉の各成分割合は、ａは８〜11.8,bは0.1
〜1.5,cは0.1〜1.5,dは0.8〜2.0及びｅは0.02〜1.0の値
をとり、ｆは他の元素の原子価を満足する酸素の原子数
である。本発明の磁性粉は、製造方法あるいは製造条件
などによっては得られる磁性粉粒子の結晶が正常な六角
板状を呈していない粒子が混在している場合もあるが、
該原子数が本発明の範囲内であれば、本発明の目的を充
分に達成することができる。The preferable ratio of each component of the magnetic powder is 8 to 11.8 for a and 0.1 for b.
.About.1.5, c is 0.1 to 1.5, d is 0.8 to 2.0, and e is 0.02 to 1.0, and f is the number of oxygen atoms satisfying the valences of other elements. Magnetic powder of the present invention, depending on the manufacturing method or manufacturing conditions, the particles of the magnetic powder particles obtained may not be a normal hexagonal plate-shaped particles may be mixed,
When the number of atoms is within the range of the present invention, the object of the present invention can be sufficiently achieved.
かかる本発明磁性粉によれば、製造方法や製造条件が異
なる場合であっても、磁気記録用磁性粉として具備され
ていなければならない保磁力及び飽和磁化を有してい
る。このことは、本発明に係る磁性粉が従来のCo及びTi
を含む磁性粉とは全く異なる機能を具備していることに
よるものと考えられる。According to the magnetic powder of the present invention, the coercive force and the saturation magnetization that must be provided as the magnetic powder for magnetic recording are provided even when the manufacturing method and the manufacturing conditions are different. This means that the magnetic powder according to the present invention has a conventional Co and Ti content.
It is considered that this is because it has a completely different function from the magnetic powder containing.
本発明による磁性粉は、この分野で公知のいろいろの方
法、例えば、ガラス結晶化法、共沈法、フラックス法、
水熱合成法等によって製造することができる。用いられ
る各元素の原料物質としては、酸化物、アンモニウム
塩、硝酸塩、炭酸塩、有機酸塩、ハロゲン化物等の塩
類、遊離酸、酸無水物、縮合酸等を挙げることができ
る。The magnetic powder according to the present invention may be obtained by various methods known in the art, for example, a glass crystallization method, a coprecipitation method, a flux method,
It can be produced by a hydrothermal synthesis method or the like. Examples of the raw material for each element used include oxides, ammonium salts, nitrates, carbonates, organic acid salts, salts such as halides, free acids, acid anhydrides, condensed acids and the like.
本発明に係る磁性粉は、六方晶Ｃ面に磁化容易軸を有す
る板状粒子であり、垂直磁気記録用磁性材料として好適
である。The magnetic powder according to the present invention is a plate-like particle having an easy axis of magnetization in the hexagonal C plane, and is suitable as a magnetic material for perpendicular magnetic recording.
本発明に係る磁性粉のうち、特に保磁力300〜2000Oe
で、且つ飽和磁化が40emu/g以上のものが賞用される。Among the magnetic powders according to the present invention, especially coercive force 300 to 2000 Oe
And the saturation magnetization of 40emu / g or more is recommended.
以下の実施例を挙げて、本発明をさらに具体的に説明す
る。なお実施例中の保磁力及び飽和磁化は、得られた磁
性粉を内径5mm、長さ5cmのガラス製試験管に充てんし、
直流磁化特性測定機を用い、最大印加磁場3500Oeで行っ
た。平均粒子径は、透過型電子顕微鏡で得られた写真か
ら400個の粒子の最大直径を測定し算術平均により算出
した。ここに掲げた実施例について、Ｘ線回折を行った
が、いずれも、磁性粉の結晶相はマグネトプランバイト
構造をもつ六方晶系フェライトであった。The present invention will be described more specifically with reference to the following examples. The coercive force and saturation magnetization in the examples were obtained by filling the obtained magnetic powder into a glass test tube having an inner diameter of 5 mm and a length of 5 cm,
The measurement was performed with a maximum applied magnetic field of 3500 Oe using a DC magnetization characteristic measuring instrument. The average particle diameter was calculated by calculating the maximum diameter of 400 particles from a photograph obtained with a transmission electron microscope and calculating the arithmetic mean. X-ray diffraction was carried out on the examples given here, and in each case, the crystal phase of the magnetic powder was a hexagonal ferrite having a magnetoplumbite structure.
また、実施例中に示す磁性粉の実験式は、原料調製時の
各金属の原子比を用いている。磁性粉成分中の酸素の表
示については、簡略化のため省略した。Further, the empirical formula of the magnetic powder shown in the examples uses the atomic ratio of each metal at the time of preparing the raw materials. The display of oxygen in the magnetic powder component is omitted for simplification.
実施例１ BaCl2・2H2O 0.55モル、TiCl4 0.375モル、CoCl2・6H2O
0.375モル、Cd(NO3)20.075モル及びFeCl3・6H2O 5.25
モルを10lの蒸留水にこの順に溶解し、これをＡ液とし
た。NaOH17.5モル及びNa2CO34.72モルを15lの室温の蒸
留水に溶解し、これをＢ液とした。50℃に熱したＡ液に
Ｂ液を徐々に加えた後、50℃で16時間攪拌した。攪拌後
のpHは10.8であった。こうして得られた共沈物を別し
充分水洗した後150℃で乾燥し、900℃で２時間電気炉で
焼成した。こうして得られたBa−フェライトはBa1.1Fe
10.5Co0.75Ti0.75Cd0.15で示される。Example 1 BaCl 2 .2H 2 O 0.55 mol, TiCl 4 0.375 mol, CoCl 2 .6H 2 O
0.375 mol, Cd (NO 3 ) 2 0.075 mol and FeCl 3・ 6H 2 O 5.25
Mol was dissolved in 10 liters of distilled water in this order, and this was designated as solution A. 17.5 mol of NaOH and 4.72 mol of Na 2 CO 3 were dissolved in 15 l of distilled water at room temperature, and this was designated as solution B. Solution B was gradually added to solution A heated to 50 ° C., and then stirred at 50 ° C. for 16 hours. The pH after stirring was 10.8. The coprecipitate thus obtained was separated, washed thoroughly with water, dried at 150 ° C., and fired at 900 ° C. for 2 hours in an electric furnace. The Ba-ferrite thus obtained is Ba 1.1 Fe.
10.5 Co 0.75 Ti 0.75 Cd 0.15
この微粒子粉末は平均粒径0.08μｍの板状であり、保磁
力は765Oe、飽和磁化は56emu/gであった。This fine particle powder had a plate shape with an average particle size of 0.08 μm, a coercive force of 765 Oe, and a saturation magnetization of 56 emu / g.
比較例１ 硝酸カドミウムを除いた他は実施例１と全く同様の方法
でBa−フェライトを製造した。得られたBa−フェライト
はBa1.1Fe10.5Co0.75Ti0.75で示される。この微粒子粉
末は平均粒径0.25μｍの板状であり、Hcは444Oe,σｓは
35emu/gであった。Comparative Example 1 Ba-ferrite was manufactured by the same method as in Example 1 except that cadmium nitrate was removed. The obtained Ba-ferrite is represented by Ba 1.1 Fe 10.5 Co 0.75 Ti 0.75 . This fine particle powder has a plate shape with an average particle size of 0.25 μm, Hc is 444 Oe, and σs is
It was 35 emu / g.
実施例２ BaCl2・2H2O0.55モル、TiCl40.375モル、CoCl2・6H2O0.
375モル、CdCl20.075モル及びFeCl3・6H2O5.25モルを、
10lの蒸留水にこの順に溶解し、これをＡ液とした。NaO
H17.5モル及びNa2CO34.72モルを15lの蒸留水に溶解し、
これをＢ液とした。50℃に熱したＡ液及びＢ液をオート
クレーブに加え300℃で４時間攪拌した後、これを室温
まで冷却した。この時のpHは10.9であった。こうして得
られた沈殿物を充分水洗後150℃で乾燥し、750℃で８時
間電気炉で熱処理した。Example 2 0.55 mol of BaCl 2 .2H 2 O, 0.375 mol of TiCl 4 and CoCl 2 .6H 2 O 0.
375 moles, CdCl 2 0.075 moles and FeCl 3 .6H 2 O 5.25 moles,
This was dissolved in 10 l of distilled water in this order, and this was designated as solution A. NaO
Dissolve 17.5 mol of H and 4.72 mol of Na 2 CO 3 in 15 l of distilled water,
This was designated as solution B. The solutions A and B heated to 50 ° C. were added to an autoclave, stirred at 300 ° C. for 4 hours, and then cooled to room temperature. The pH at this time was 10.9. The precipitate thus obtained was thoroughly washed with water, dried at 150 ° C., and heat-treated at 750 ° C. for 8 hours in an electric furnace.
こうして得られるBa−フェライトは Ba1.1Fe10.5Co0.75Ti0.75Cd0.15で示される。The Ba-ferrite thus obtained is represented by Ba 1.1 Fe 10.5 Co 0.75 Ti 0.75 Cd 0.15 .
この微粒子粉末は、平均粒径0.11μｍの板状であり、Hc
は、779Oe、σｓは50emu/gであった。この結果から、本
実施例の水熱合成法を用いても、実施例１の共沈法を用
いても、ほぼ同じ磁気特性を有する磁性粉が得られるこ
とが分る。This fine particle powder has a plate shape with an average particle size of 0.11 μm,
Was 779 Oe, and σs was 50 emu / g. From this result, it can be seen that magnetic powder having almost the same magnetic characteristics can be obtained by using the hydrothermal synthesis method of the present embodiment or the coprecipitation method of the first embodiment.
比較例２ 塩化カドミウムを除いた他は、実施例２と全く同様の方
法でBa−フェライトを製造した。得られたBa−フェライ
トはBa1.1Fe10.5Co0.75Ti0.75で示される。この微粒子
粉末の平均粒径は、0.33μｍの板状であり、Hcは2250e,
σｓは21emu/gであった。Comparative Example 2 Ba-ferrite was produced in the same manner as in Example 2 except that cadmium chloride was removed. The obtained Ba-ferrite is represented by Ba 1.1 Fe 10.5 Co 0.75 Ti 0.75 . The average particle size of this fine particle powder is 0.33 μm, and the Hc is 2250e,
σs was 21 emu / g.
実施例３ Ｂ液中のNaOHを25.0モルとした他は、実施例１と全く同
様の方法でBa−フェライトを製造した。Example 3 Ba-ferrite was produced in the same manner as in Example 1 except that NaOH in the solution B was changed to 25.0 mol.
この微粒子粉末は、平均粒径0.11μｍの板状であり、Hc
は、770Oe,σｓは52emu/gであった。This fine particle powder has a plate shape with an average particle size of 0.11 μm,
Was 770 Oe and σs was 52 emu / g.
比較例３ Ｂ液中のNaOHを25.0モルとした他は、比較例１と全く同
様の方法でBa−フェライトを製造した。Comparative Example 3 Ba-ferrite was produced in the same manner as in Comparative Example 1 except that NaOH in the solution B was changed to 25.0 mol.
この微粒子粉末は、平均粒径0.13μｍの板状であり、Hc
は920Oe、σｓは23emu/gであった。This fine particle powder has a plate shape with an average particle size of 0.13 μm,
Was 920 Oe and σs was 23 emu / g.
実施例１〜３の結果から、本発明に係る磁性粉は製造条
件が異ってもほぼ同一性能を有する磁性粉が得られるこ
とがわかる。From the results of Examples 1 to 3, it can be seen that the magnetic powder according to the present invention can be obtained with almost the same performance even under different manufacturing conditions.
実施例４〜23 MI成分MII成分及び組成比を変えた他は、実施例１と同
様の方法によって表２に示す磁性粉を調製した。なお、
MI成分の原料は塩化物を使用し、MII成分の原料はAgは
硝酸銀、Teはオルトテルル酸、ｐはオルトリン酸、Asは
ヒ酸、Biは硝酸ビスマス、及びSiはケイ酸ナトリウムを
使用した。Examples 4 to 23 M I component A magnetic powder shown in Table 2 was prepared in the same manner as in Example 1 except that the M II component and the composition ratio were changed. In addition,
Raw material for the M I component using the chloride, the raw material is Ag is silver nitrate M II components, Te is Orutoteruru acid, p is orthophosphoric acid, As Wahisan, Bi is bismuth nitrate, and Si using sodium silicate did.
なお、ケイ酸ナトリウムはＢ液中に溶解した。The sodium silicate was dissolved in the liquid B.
Claims (1)
子径0.01〜0.3μｍであることを特徴とする塗布膜タイ
プの磁気記録用磁性粉 FeaCobTicMI dMII eOf （ここでMIはBa、Sr、Ca及びPbから選択される少なくと
も一種の金属元素を表わし、MIIはCd、Ag、Te、Ｐ、A
s、Bi及びSiから選択される少なくとも一種の金属元素
を表わし、ａ、ｂ、ｃ、ｄ、ｅ及びｆはそれぞれFe、C
o、Ti、MI、MII及びＯの原子数であり、ａは８〜11.8、
ｂは0.05〜2.0、ｃは0.05〜2.0、ｄは0.5〜3.0及びｅは
0.01〜2.0の値をとり、ｆは他の元素の原子価を満足す
る酸素の原子数である。）1. A coating film type magnetic powder Fe a Co b Ti c M I d M II represented by the following general composition formula and having an average particle diameter of 0.01 to 0.3 μm. e O f (wherein M I represents Ba, Sr, at least one metallic element selected from Ca and Pb, M II is Cd, Ag, Te, P, a
Represents at least one metal element selected from s, Bi and Si, where a, b, c, d, e and f are Fe and C, respectively.
o is the number of atoms of Ti, M I , M II and O, and a is 8 to 11.8,
b is 0.05 to 2.0, c is 0.05 to 2.0, d is 0.5 to 3.0, and e is
The value is 0.01 to 2.0, and f is the number of oxygen atoms satisfying the valences of other elements. )
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60262139A JPH06104574B2 (en) | 1985-11-21 | 1985-11-21 | Coating film type magnetic powder for magnetic recording |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60262139A JPH06104574B2 (en) | 1985-11-21 | 1985-11-21 | Coating film type magnetic powder for magnetic recording |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62123023A JPS62123023A (en) | 1987-06-04 |
| JPH06104574B2 true JPH06104574B2 (en) | 1994-12-21 |
Family
ID=17371594
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60262139A Expired - Lifetime JPH06104574B2 (en) | 1985-11-21 | 1985-11-21 | Coating film type magnetic powder for magnetic recording |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06104574B2 (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63195125A (en) * | 1987-02-06 | 1988-08-12 | Ube Ind Ltd | Barium ferrite magnetic powder and production thereof |
| JPS6435901A (en) * | 1987-07-30 | 1989-02-07 | Toshiba Glass Kk | Magnetic powder and manufacture thereof |
| JPH01164008A (en) * | 1987-09-30 | 1989-06-28 | Toshiba Corp | Magnetic powder for high density magnetic recording and magnetic recording medium employing same |
| JPH01282129A (en) * | 1988-05-10 | 1989-11-14 | Ube Ind Ltd | Barium ferrite magnetic powder and its production |
| JPH02289431A (en) * | 1989-04-28 | 1990-11-29 | Ube Ind Ltd | Barium ferrite magnetic powder and its production |
| JP3095047B2 (en) * | 1993-01-28 | 2000-10-03 | 戸田工業株式会社 | Magnetoplumbite-type ferrite particle powder for magnetic card and method for producing the same |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6189607A (en) * | 1984-10-09 | 1986-05-07 | Ricoh Co Ltd | Metal oxide magnetic substance and magnetic film |
| JPS6189606A (en) * | 1984-10-09 | 1986-05-07 | Ricoh Co Ltd | Metal oxide magnetic substance and magnetic film |
| JPS60211904A (en) * | 1984-04-06 | 1985-10-24 | Ricoh Co Ltd | Magnetic substance and magnetic film of metal oxide |
| JPS61136923A (en) * | 1984-12-07 | 1986-06-24 | Fuji Photo Film Co Ltd | Hexagonal ferrite magnetic body for magnetic recording and its manufacture |
| JP2509558B2 (en) * | 1985-08-29 | 1996-06-19 | 株式会社東芝 | Magnetic powder for high density magnetic recording and magnetic recording medium using the same |
-
1985
- 1985-11-21 JP JP60262139A patent/JPH06104574B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62123023A (en) | 1987-06-04 |
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