JPS59157838A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPS59157838A JPS59157838A JP58031939A JP3193983A JPS59157838A JP S59157838 A JPS59157838 A JP S59157838A JP 58031939 A JP58031939 A JP 58031939A JP 3193983 A JP3193983 A JP 3193983A JP S59157838 A JPS59157838 A JP S59157838A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- layer
- magnetic recording
- magnetization
- recording medium
- 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
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 171
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims abstract description 76
- 230000005415 magnetization Effects 0.000 claims abstract description 58
- 239000010409 thin film Substances 0.000 abstract description 23
- 239000000758 substrate Substances 0.000 abstract description 21
- 238000004544 sputter deposition Methods 0.000 abstract description 19
- 238000000034 method Methods 0.000 abstract description 17
- 239000011230 binding agent Substances 0.000 abstract description 16
- 230000035945 sensitivity Effects 0.000 abstract description 5
- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 abstract description 4
- 229910020630 Co Ni Inorganic materials 0.000 abstract description 3
- 229910002440 Co–Ni Inorganic materials 0.000 abstract description 3
- 230000032683 aging Effects 0.000 abstract description 3
- 230000008569 process Effects 0.000 abstract description 2
- 229910006297 γ-Fe2O3 Inorganic materials 0.000 abstract 2
- 238000005260 corrosion Methods 0.000 abstract 1
- 230000007797 corrosion Effects 0.000 abstract 1
- 239000010408 film Substances 0.000 description 37
- 235000013980 iron oxide Nutrition 0.000 description 37
- 229910000859 α-Fe Inorganic materials 0.000 description 18
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 16
- 239000007789 gas Substances 0.000 description 11
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- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 6
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- VBMVTYDPPZVILR-UHFFFAOYSA-N iron(2+);oxygen(2-) Chemical class [O-2].[Fe+2] VBMVTYDPPZVILR-UHFFFAOYSA-N 0.000 description 4
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- 229910018605 Ni—Zn Inorganic materials 0.000 description 2
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- IPCSVZSSVZVIGE-UHFFFAOYSA-N hexadecanoic acid Chemical compound CCCCCCCCCCCCCCCC(O)=O IPCSVZSSVZVIGE-UHFFFAOYSA-N 0.000 description 2
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- IIZPXYDJLKNOIY-JXPKJXOSSA-N 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine Chemical compound CCCCCCCCCCCCCCCC(=O)OC[C@H](COP([O-])(=O)OCC[N+](C)(C)C)OC(=O)CCC\C=C/C\C=C/C\C=C/C\C=C/CCCCC IIZPXYDJLKNOIY-JXPKJXOSSA-N 0.000 description 1
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- LSNNMFCWUKXFEE-UHFFFAOYSA-M Bisulfite Chemical compound OS([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-M 0.000 description 1
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- QORUGOXNWQUALA-UHFFFAOYSA-N N=C=O.N=C=O.N=C=O.C1=CC=C(C(C2=CC=CC=C2)C2=CC=CC=C2)C=C1 Chemical compound N=C=O.N=C=O.N=C=O.C1=CC=C(C(C2=CC=CC=C2)C2=CC=CC=C2)C=C1 QORUGOXNWQUALA-UHFFFAOYSA-N 0.000 description 1
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- 230000003746 surface roughness Effects 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- DVKJHBMWWAPEIU-UHFFFAOYSA-N toluene 2,4-diisocyanate Chemical compound CC1=CC=C(N=C=O)C=C1N=C=O DVKJHBMWWAPEIU-UHFFFAOYSA-N 0.000 description 1
- ITRNXVSDJBHYNJ-UHFFFAOYSA-N tungsten disulfide Chemical compound S=[W]=S ITRNXVSDJBHYNJ-UHFFFAOYSA-N 0.000 description 1
- 125000004417 unsaturated alkyl group Chemical group 0.000 description 1
- 238000007738 vacuum evaporation Methods 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- 239000008096 xylene Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/62—Record carriers characterised by the selection of the material
- G11B5/64—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent
- G11B5/65—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition
- G11B5/658—Record carriers characterised by the selection of the material comprising only the magnetic material without bonding agent characterised by its composition containing oxygen, e.g. molecular oxygen or magnetic oxide
Landscapes
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Magnetic Record Carriers (AREA)
- Paints Or Removers (AREA)
- Physical Vapour Deposition (AREA)
Abstract
Description
【発明の詳細な説明】
■、産業上の利用分野
本発明は磁気テープ、磁気ディスク等の磁気記録媒体に
関するものである。DETAILED DESCRIPTION OF THE INVENTION (1) Industrial Application Field The present invention relates to magnetic recording media such as magnetic tapes and magnetic disks.
2、 従来技術
従来、この種の磁気記録媒体は、ビデオ、オーディオ、
ディジタル等の各種電気信号の記録に幅広く利用されて
いる。 これらは、基体上に被着形成された磁性層(磁
気記録層)の面内長手方向における磁化を用いる方式と
して発達してきた。2. Prior Art Conventionally, this type of magnetic recording medium has been used for video, audio,
It is widely used for recording various electrical signals such as digital ones. These have been developed as a system that uses magnetization in the in-plane longitudinal direction of a magnetic layer (magnetic recording layer) formed on a substrate.
ところが、近年、磁気記録の高密度化に伴ない、面内長
手方向の磁化を用いる記録方式では、記録信号が短波長
になるにつれ、媒体内の反磁界が増して残留磁化の減衰
と回転が生じ、再生出力が著しく減少する。 このため
、記録波長をサブミクロン以下にすることは極めて困難
である。However, in recent years, with the increase in the density of magnetic recording, recording methods that use magnetization in the longitudinal direction in the plane have a tendency to increase the demagnetizing field within the medium as the recording signal becomes shorter in wavelength, resulting in attenuation and rotation of the residual magnetization. This causes a significant decrease in playback output. For this reason, it is extremely difficult to reduce the recording wavelength to submicron or less.
一方、磁気記録媒体の磁性層の厚さ方向の磁化(いわゆ
る垂直磁化)を用いる垂直磁化記録方式が、最近になっ
て提案されている(例えば、[日経エレクトロニクスJ
1978年8月7日号A 192 )。On the other hand, a perpendicular magnetization recording method that uses magnetization in the thickness direction of the magnetic layer of a magnetic recording medium (so-called perpendicular magnetization) has recently been proposed (for example, [Nikkei Electronics J
August 7, 1978 issue A 192).
この記録方式によれば、記録波長が短かくなるに伴なっ
て媒体内の残留磁化に作用する反磁界が減少するので、
高密度化にとって好ましい特性を有し、本質的に高密度
記録に適した方式であると考えられる。According to this recording method, as the recording wavelength becomes shorter, the demagnetizing field that acts on the residual magnetization in the medium decreases.
This method is considered to have favorable characteristics for high-density recording and is essentially suitable for high-density recording.
また、二層以上の磁性層を有する磁気記録媒体が、塗布
型の磁性層に関してはオーディオ用磁気テープとして知
られている。Further, a magnetic recording medium having two or more magnetic layers is known as an audio magnetic tape in terms of coated magnetic layers.
例えば特開昭54−125006号公報によれば、磁性
粉をバインダに分散させた塗料をまず基体上に塗布して
1層目の塗布型長手記録磁性層(面内方向に磁化容易軸
あり)を形成し、この上に1バインダを使用せずに磁性
粒子の連続薄膜からなる連続薄膜型長手記録磁性層を形
成し、ている。 しかしこの媒体では、1層目の塗布型
磁性層の熱伝導率が悪く、シかも上層の磁性層を構成す
る物質を被着せしめた場合の潜熱及び被着手段からの輻
射熱が作用して、塗布型磁性層が破壊され易い。For example, according to Japanese Patent Application Laid-Open No. 54-125006, a coating material in which magnetic powder is dispersed in a binder is first applied onto a substrate to form a coated longitudinal recording magnetic layer (with an axis of easy magnetization in the in-plane direction). A continuous thin film type longitudinal recording magnetic layer consisting of a continuous thin film of magnetic particles is formed thereon without using a binder. However, in this medium, the thermal conductivity of the first coated magnetic layer is poor, and the latent heat when the material constituting the upper magnetic layer is deposited and the radiant heat from the deposition means act. The coated magnetic layer is easily destroyed.
このだめ、得られた磁気記録媒体は表面粗さの精度が充
分でなく、かつドロラグアウトが多くてS/N比が劣化
したものにしかならない。Unfortunately, the obtained magnetic recording medium does not have sufficient precision in surface roughness, has many lag-outs, and has a degraded S/N ratio.
まだ、1層目にCo、γ−Fe2es、Fe3O4、C
o−Ni等の連続薄膜型面内磁気異方性磁性層を形成し
、2層目にCo−GrlXFe−Gd等の連続薄膜型垂
直磁気異方性磁性Nを形成した磁気記録媒体が特開昭5
4−1451.05号公報に示されている0 しかじな
がら、この媒体では、磁性層自体の耐久性、経時変化が
悪く、このために充分なS/N比で高記録密度の記録/
再生を行なうことができない。Co, γ-Fe2es, Fe3O4, C are still in the first layer.
A magnetic recording medium in which a continuous thin film type in-plane magnetic anisotropic magnetic layer such as o-Ni is formed and a continuous thin film type perpendicular magnetic anisotropic magnetic layer N such as Co-GrlXFe-Gd is formed in the second layer is disclosed Showa 5
However, in this medium, the durability and aging of the magnetic layer itself are poor, and for this reason, it is difficult to record at a high recording density with a sufficient S/N ratio.
Unable to perform playback.
3、発明の目的
本発明の目的は、上記の如き複数の磁性層を有する磁気
記録媒体が例えば周波数特性が良好であることに着目し
、その周波数特性及び再生出力を更に向上させると共に
、高記録密度の記録/再生が可能であって経時変化の少
ない低コストな磁気記録媒体を提供することにある。3. Purpose of the Invention The purpose of the present invention is to focus on the fact that a magnetic recording medium having a plurality of magnetic layers as described above has, for example, good frequency characteristics, and to further improve its frequency characteristics and reproduction output, as well as to achieve high recording speed. It is an object of the present invention to provide a low-cost magnetic recording medium that is capable of high-density recording/reproduction and has little change over time.
4、発明の構成及びその作用効果
即ち、本発明は、複数の磁気記録層を有し、かつ少なく
とも1つの磁気記録層が、。4. Structure of the invention and its effects, that is, the present invention has a plurality of magnetic recording layers, and at least one magnetic recording layer.
(a)、酸化鉄を主成分゛とする連続磁性層からなって
いること。(a) Consisting of a continuous magnetic layer whose main component is iron oxide.
(b)、磁性層の面内方向での残留磁化(MH)と、磁
性層の面に対し垂直方向での残留磁化(MY)との比(
Mv / Mu )が0.5以上であること〇を夫々構
成として具備することを特徴とする磁気記録媒体に係る
ものである。(b), the ratio of the residual magnetization (MH) in the in-plane direction of the magnetic layer to the residual magnetization (MY) in the perpendicular direction to the plane of the magnetic layer (
The present invention relates to a magnetic recording medium characterized in that it has the following configuration: Mv/Mu) is 0.5 or more.
本発明によれば、磁気記録層が2以上からなシ、少なく
とも1つの磁性層が酸化鉄を主成分としているから、酸
化物に由来する特有の優れた特性(即ち機械的強既及び
化学的女定性、低コスト等)が得られ、表面保護膜は不
要となる。 この結果、磁気ヘッドと媒体との開削を小
さくシ得て高密度記録が可能になると共に、材料面から
みても低コスト化が可能となる。According to the present invention, since the magnetic recording layer is composed of two or more, and at least one magnetic layer has iron oxide as a main component, it has excellent characteristics unique to oxides (i.e., mechanical strength and chemical resistance). (female quality, low cost, etc.), and a surface protective film is not required. As a result, the cutting distance between the magnetic head and the medium can be reduced to allow high-density recording, and costs can also be reduced from a material standpoint.
しかも、酸化鉄を主成分とする磁気記録層の面内方向と
垂直方向とでの残留磁化比(Mv/ MW )を0.5
以上としているので、酸化鉄磁性体の磁気モーメントは
面内方向に対し30度以上垂直方向側へ立ち上ってお)
、垂直磁化を充分にかつ高密度で実現でき、再生出力を
大きくできる構造となっている。 上記磁化量MvXM
Hは、しUえは試料振動型磁力計(東英工業社製)で測
定可能である。Moreover, the residual magnetization ratio (Mv/MW) in the in-plane direction and the perpendicular direction of the magnetic recording layer containing iron oxide as the main component is 0.5.
Because of the above, the magnetic moment of the iron oxide magnetic material rises more than 30 degrees perpendicular to the in-plane direction.)
, it has a structure that can realize sufficient perpendicular magnetization at high density and can increase the reproduction output. The above magnetization amount MvXM
H can be measured using a sample vibrating magnetometer (manufactured by Toei Kogyo Co., Ltd.).
即ち、Mv/MHが05未満であれば垂直磁化に適した
磁気モーメントが得られ難い。That is, if Mv/MH is less than 05, it is difficult to obtain a magnetic moment suitable for perpendicular magnetization.
また、本発明の磁気記録媒体は、上記の・酸化鉄系磁気
記録層に加えて、その他に1以上の磁気記録層を設けて
いるから、これらの各磁気記録層の組合せによって、低
域及び高域の双方での記録/再生特性を良好として周波
数特性を向−ヒさせたシ、或いは磁気還流効果による残
留磁化の保持性、垂直配向性等を向上させ、ることかで
きる。Furthermore, since the magnetic recording medium of the present invention is provided with one or more other magnetic recording layers in addition to the iron oxide-based magnetic recording layer described above, the combination of these magnetic recording layers enables low frequency and It is possible to improve the frequency characteristics by improving the recording/reproducing characteristics in both high frequencies, or to improve the retention of residual magnetization by the magnetic reflux effect, the perpendicular orientation, etc.
本発明の磁気記録媒体に使用する上記酸化銑系の磁気記
録層は、従来の塗布型磁性層とは根本的に異なジ、バイ
ンダーを使用せずに酸化鉄(I!AJえばFes 04
、γ−Fe20a 、又はこれらの中間組成の非化学
量論的組成からなるベルトライド化合物)自体が連続的
に連なった薄膜(飽和磁化量が大きく、保S力(aC)
が100〜50000e)からなっている。The iron oxide-based magnetic recording layer used in the magnetic recording medium of the present invention is fundamentally different from conventional coated magnetic layers.
, γ-Fe20a, or a beltlide compound consisting of a non-stoichiometric composition intermediate between these) itself is a continuous thin film (with a large saturation magnetization and a low coercive force (aC)).
100 to 50,000e).
この磁性層においては、鉄と酸素の両元素の総和は磁性
層の、50重量%以上であるのがよく、70重量係以上
であるのが更に望ましい。 また、鉄と酸素との比は、
酸素の原子数/鉄の原子数=1〜3であるのがよく、y
3〜2であるのが更によく、上記に例示した酸化鉄が適
当である。 上記酸化鉄がスピネル型の結晶構造を有し
ていると、飽和磁化量が大きく、記録信号の再生時に残
留磁束i度が大きくて再生感度が極めて良好となる。
一般に、磁性を示す酸化鉄には°、菱面体晶形の寄生強
磁性を有するα−Feze3;スピネル構造でフェリ磁
性を示すFe a Oa 、γ−FezOa又はこれら
のベルトジイド化合物;六方晶型の酸化物であるBa系
フェライト又はSrフェライト、Pbフェライト又はそ
の誘導体ニガーネット構造の希土類ガーネット型フェラ
イトがある。 これらの酸化鉄のうち、その磁気特性の
重要な1つである飽和磁化量は、α−F e 20sで
は2.OGauss、Baフェライト、Sr 7 エラ
イトらフェライトでは最大でも380 Gauss程度
、更にガーネット型フェライトでは最大でも140Ga
ussである。これに対し、本発明で好ましく使用する
スピネル型フェライトの飽和磁化量は480Gauss
を示し、酸化鉄の中で最も大きい。 このような大きな
飽和磁化量は、記録した信号を再生する場合、残留磁束
密度の大きさを充分にし、再生感度が良好となるために
、極めて有効なものである。 一方、スピネル型フェラ
イトに類似した飽和磁束密度を示すものとしてBaフェ
ライ1.、Srフェライトがあるが、これらの連続薄膜
屋の磁性層を形成するには、例えばスパッタ装置におい
て基体の温度を500°Cと高温に保持しなければなら
ず、このために基体の種類等が制約される(例えば耐熱
性の乏しいプラスチックス基体は使用不可能)等、作成
条件に問題があシ、不適当である。In this magnetic layer, the sum of both elements iron and oxygen is preferably 50% by weight or more, more preferably 70% by weight or more of the magnetic layer. Also, the ratio of iron to oxygen is
It is preferable that the number of oxygen atoms/the number of iron atoms = 1 to 3, and y
It is even better that the number is 3 to 2, and the iron oxides exemplified above are suitable. When the iron oxide has a spinel-type crystal structure, the amount of saturation magnetization is large, and the residual magnetic flux i degree is large during reproduction of a recorded signal, resulting in extremely good reproduction sensitivity.
In general, iron oxides that exhibit magnetism include α-Feze3, which has rhombohedral parasitic ferromagnetism; Fe a Oa, γ-FezOa, or their belt diode compounds, which exhibit ferrimagnetism in a spinel structure; hexagonal oxides. There are rare earth garnet type ferrites having a Ba-based ferrite, Sr ferrite, Pb ferrite, or its derivative nigernet structure. Among these iron oxides, the saturation magnetization, which is one of the important magnetic properties, is 2. Ferrites such as OGauss, Ba ferrite, and Sr 7 erite have a maximum of about 380 Gauss, and garnet type ferrites have a maximum of 140 Ga.
It is USS. On the other hand, the saturation magnetization of the spinel ferrite preferably used in the present invention is 480 Gauss.
It is the largest of all iron oxides. Such a large amount of saturation magnetization is extremely effective when reproducing a recorded signal because it ensures a sufficient residual magnetic flux density and improves reproduction sensitivity. On the other hand, Ba ferrite 1. exhibits a saturation magnetic flux density similar to that of spinel type ferrite. , Sr ferrite, but in order to form these continuous thin film magnetic layers, the temperature of the substrate must be maintained at a high temperature of 500°C in a sputtering device, for example, and for this reason, the type of substrate, etc. There are problems with the production conditions, such as restrictions (for example, the use of plastic substrates with poor heat resistance cannot be used), and the production conditions are inappropriate.
本発明の好ましく使用されるスピネル型酸化鉄では室温
〜300°Cと低温で製膜が可能であり、基体材料の制
約を受けることがない。 但、磁性層には、鉄及び酸素
以外の金属又はその酸化物、或いは非金属、半金属又は
その化合物等を添加し、これによって磁性層の磁気特性
(例えば保磁力、飽和磁化量、残留磁化量)及びその結
晶性、結晶の特定軸方向への配向性の向上環を図ること
ができる。 こうした添加元素又は化合物としてはA1
゜Co、 Co −Mn、 ZnXCo −Zn、 L
i、 CrXTi、Lt−Cr、 MgN Mg−Ni
、 Mn−Zn、 Ni 、 Ni −At。The spinel-type iron oxide preferably used in the present invention can be formed into a film at a low temperature of room temperature to 300°C, and is not subject to restrictions on the substrate material. However, metals other than iron and oxygen or their oxides, nonmetals, semimetals, or compounds thereof are added to the magnetic layer, thereby improving the magnetic properties of the magnetic layer (e.g. coercive force, saturation magnetization, residual magnetization). amount), its crystallinity, and the orientation of the crystal in a specific axial direction. These additive elements or compounds include A1
゜Co, Co-Mn, ZnXCo-Zn, L
i, CrXTi, Lt-Cr, MgN Mg-Ni
, Mn-Zn, Ni, Ni-At.
Ni −Zn、 CulCu−Mn、Cu −ZnXV
等が挙げられるが、この他の元素及び化合物でもよい。Ni-Zn, CulCu-Mn, Cu-ZnXV
etc., but other elements and compounds may also be used.
上記酸化鉄系垂直磁化用の磁気記録層に加えて設ける他
の磁気記録層としては、−以下に示す如き面内方向に磁
化容易軸をもつものと、面内方向と垂直方向に磁化容易
軸をもつものとがある。Other magnetic recording layers to be provided in addition to the above-mentioned iron oxide-based magnetic recording layer for perpendicular magnetization include those with an easy axis of magnetization in the in-plane direction as shown below, and those with an easy axis of magnetization in a direction perpendicular to the in-plane direction. There are things that have .
(■)、面内方向に磁化容易軸をもつ磁気記録層(a)
、塗布型磁性層
これにはまず、Co XFe$ 04、r Feze
s、C。(■), magnetic recording layer with easy axis of magnetization in the in-plane direction (a)
, coated magnetic layer. First, Co XFe$ 04, r Feze
s,C.
被着γ−FIB2011 % Crow等を磁性粉とし
て用い、保磁力(H(りが2oo〜3ooooe〕磁気
特性ヲ付与せしめたものがある0 そして、低周波から
高周波までの周波数特性に優れた電磁変換特性を実現で
きる。 Hoが2000e未満だと記録信号の保存性が
悪り、3ooooeを越えると電気−磁気の相互作用を
用いて信号を記録することが困難となる。There are some that use adhering γ-FIB2011% Crow etc. as magnetic powder to give magnetic properties of coercive force (H (Riga 2oo~3ooooe)). If Ho is less than 2000e, the storage stability of recorded signals will be poor, and if it exceeds 3ooooe, it will be difficult to record signals using electric-magnetic interaction.
また別の塗布型磁気記録層の磁性粉として、Co−Fe
、 Fe、 Fe−8i、パーマロイ、センダスト、ミ
ーメタル、Mn −Znフェライト、Ni−Znフェラ
イト、Cu−Zn7エライト等がある。 この場合、
Hoが低((2000e以下、望ましくは1゜Oe以下
)、透磁率の高い軟磁性磁性粉が適用可能であるが、軟
磁性を付与することにより記録時に磁束を集中させ、か
つ記録後の減磁作用を少なくして記録保持性を向上させ
ることができる。 つまシ、高透磁率磁気記録層が磁束
(フラックス)を通し易い性質があるために、磁極から
の磁束を磁性層に集中させると共に、磁気還流効果によ
って残留磁化を充分に保持させる効果があり、記録密度
を損なうことなく記録/再生の感度及び再生出力を向上
させることができる。Co-Fe is also used as magnetic powder for another coated magnetic recording layer.
, Fe, Fe-8i, permalloy, sendust, mimetal, Mn-Zn ferrite, Ni-Zn ferrite, Cu-Zn7 elite, etc. in this case,
Soft magnetic powder with low Ho (2000e or less, preferably 1°Oe or less) and high magnetic permeability can be applied, but by imparting soft magnetism, it is possible to concentrate the magnetic flux during recording and reduce the decrease after recording. It is possible to improve recording retention by reducing the magnetic effect. Since the high magnetic permeability magnetic recording layer has the property of allowing magnetic flux to pass through easily, it concentrates the magnetic flux from the magnetic poles on the magnetic layer and The magnetic reflux effect has the effect of sufficiently retaining residual magnetization, and it is possible to improve recording/reproducing sensitivity and reproduction output without impairing recording density.
この塗布型磁気記録層を形成するのに用いる磁性塗料に
は、必要に応じて分散剤、潤滑剤、研磨剤、帯電防止剤
等の添加剤を含有させてもよい。 また、使用可能なバ
インダとしては、従来公知の熱可塑性樹脂、熱硬化性樹
脂、反応型樹脂または電子線照射硬化型樹脂や、これら
の混合物が使用される。 熱可塑性樹脂としては、軟化
温朋が150°C以下、平均分子量が10,000〜2
0Q、000重合度が約200〜2,000程度のもの
′で、例えば塩化ビニル−酢酸ビニル共重合体、塩化ビ
ニル−塩化ビニリデン共重合体、塩化とニル−アクリロ
ニトリル共重合体、アクリル酸エステル−アクリロニト
リル共重合体、ウレタンニジストマー、塩化ビニリデン
−アクリロニトリル共重合体、セルロース誘導体(セル
ロースアセテートブチレート、セルロースダイアセテー
ト、セルローストリアセテート、セルロースグロピオネ
ート、ニトロセルロース等)、ポリエステル樹脂、およ
びこれらの混合物等が使用される。The magnetic paint used to form this coated magnetic recording layer may contain additives such as a dispersant, a lubricant, an abrasive, an antistatic agent, and the like, if necessary. Furthermore, usable binders include conventionally known thermoplastic resins, thermosetting resins, reactive resins, electron beam curable resins, and mixtures thereof. The thermoplastic resin has a softening temperature of 150°C or less and an average molecular weight of 10,000 to 2.
0Q, 000 polymerization degree of about 200 to 2,000, such as vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer, acrylic ester- Acrylonitrile copolymers, urethane distomers, vinylidene chloride-acrylonitrile copolymers, cellulose derivatives (cellulose acetate butyrate, cellulose diacetate, cellulose triacetate, cellulose glopionate, nitrocellulose, etc.), polyester resins, and mixtures thereof, etc. is used.
熱硬化性樹脂または反応型樹脂としては、塗布液の状態
では200.000以下の分子量であり、塗布乾燥後に
は縮合、付加等の反応により分子量は無限大のものとな
る。 また、とれらの樹脂のなかで樹脂が熱分解するま
での間に軟化または溶融しないものが好ましい。 具体
的には、例えばエポキシ樹脂、ポリウレタン硬化型樹脂
、シリコン樹脂、アクリル系反応樹脂、高分子量ポリエ
ステル樹脂とインシアネートプレポリマーの混合物、メ
タクリル酸塩共重合体とジインシアネートプレポリマー
の混合物、ポリエステルポリオールとポリイソシアネー
トの混合物、低分子量グリコール/高分子量ジオール/
トリフェニルメタントリイソシアネートの混合物、およ
びこれらの混合物等である。 電子線照射硬化型樹脂と
しては、不飽和プレポリマー、例えば無水マレイン酸タ
イプ、ウレタンアクリルタイプ、エポキシアクリルタイ
プ、ポリエステルアクリルタイプ、ポリエーテルアクリ
ルタイプ、ポリウレタンアクリルタイプ、ポリアミドア
クリルタイプ等、または多官北上ツマ−として、エーテ
ルアクリルタイプ、つVタンアクリルタイプ、エポキシ
アクリルタイプ、リン酸エステルアクリルタイプ等が挙
げられる。The thermosetting resin or reactive resin has a molecular weight of 200,000 or less in the state of a coating liquid, and after coating and drying, the molecular weight becomes infinite due to reactions such as condensation and addition. Moreover, among these resins, those that do not soften or melt before the resin is thermally decomposed are preferable. Specifically, examples include epoxy resins, polyurethane curable resins, silicone resins, acrylic reaction resins, mixtures of high molecular weight polyester resins and incyanate prepolymers, mixtures of methacrylate copolymers and diincyanate prepolymers, and polyester polyols. and polyisocyanate, low molecular weight glycol/high molecular weight diol/
These include mixtures of triphenylmethane triisocyanate and mixtures thereof. Examples of electron beam irradiation-curable resins include unsaturated prepolymers such as maleic anhydride type, urethane acrylic type, epoxy acrylic type, polyester acrylic type, polyether acrylic type, polyurethane acrylic type, polyamide acrylic type, etc., or polyfunctional Kitakami. Examples of the materials include ether acrylic type, V-tan acrylic type, epoxy acrylic type, and phosphate ester acrylic type.
これらのバインダの単独または紹合わされたものが使わ
れ、必要に応じて他に添加剤が加えられる。 強磁性粉
末とバインダとの混合割合は、該強磁性粉末100重量
部に対してバインダ10〜400重量部、好ましくは3
0〜200重量部の範囲で使用される。 バインダが多
すぎると磁気記録媒体としたときの記録密度が低下し、
少なすぎると磁性層の強度が劣シ、耐久性の減少等の好
ましくない事態が生じる。These binders may be used alone or in combination, and other additives may be added as necessary. The mixing ratio of the ferromagnetic powder and the binder is 10 to 400 parts by weight, preferably 3 parts by weight, of the binder to 100 parts by weight of the ferromagnetic powder.
It is used in a range of 0 to 200 parts by weight. If there is too much binder, the recording density will decrease when used as a magnetic recording medium.
If the amount is too small, undesirable situations such as poor strength and durability of the magnetic layer will occur.
式うに本発明にかかる磁気記録媒体の耐久性を向上させ
るために磁性層に各種硬化剤を含有させることができ、
レリえはポリイソシアネート?含有させることができる
。 列としては、トリレンジイソシアネート3モルとト
リメチロールプロパン1モルの付加体、メタキシリレン
ジインシアネート3モルとトリメチロールプロパン1モ
ルの付加体があげられる。In order to improve the durability of the magnetic recording medium according to the present invention, the magnetic layer can contain various curing agents,
Is the relay made of polyisocyanate? It can be included. Examples of the series include an adduct of 3 moles of tolylene diisocyanate and 1 mole of trimethylolpropane, and an adduct of 3 moles of metaxylylene diisocyanate and 1 mole of trimethylolpropane.
磁性層には、さらに前記強磁性粉末、前記のバインダ、
硬化剤の他に添加剤として分散剤、潤滑剤、°研磨剤、
帯電防止剤等が加えられてもよい。 使用されてもよい
分散剤としては、カプリル酸、パルミチン酸、ステアリ
ン酸、オレイン酸等の炭素原子数8〜18個の脂肪酸(
R−COOHで表わされRは炭素原子数7〜17個の飽
和または不飽和のアルキル基):前記の脂肪酸のアルカ
リ金属(Li、 Na、 K等)またはプルカリ土類金
属(Mg、 Ca、 Ba、等)の塩二ビシチン等があ
げられる。 この他に炭素原子数12以上の高級アルコ
ールおよびこれらの他に硫酸エステル等も使用可能であ
る。 また市販の一般の界面活性剤を使用することもで
きる。 これらの分散剤は1種類のみで用いても、ある
いは2種類以上を併用してもよい。 これらの分散剤は
バインダ100重量部に対して1〜20重量部の範囲で
添加される。 潤滑剤としては、シリコンオイル、カー
ボンブラック、グラファイト、カーボンブラックグラフ
トポリマー、二硫化モリフ2デン、二硫化タングステン
等も使用できる。The magnetic layer further includes the ferromagnetic powder, the binder,
In addition to hardeners, additives include dispersants, lubricants, polishing agents,
Antistatic agents and the like may also be added. Dispersants that may be used include fatty acids having 8 to 18 carbon atoms, such as caprylic acid, palmitic acid, stearic acid, and oleic acid.
(represented by R-COOH, where R is a saturated or unsaturated alkyl group having 7 to 17 carbon atoms): an alkali metal (Li, Na, K, etc.) or prucarious earth metal (Mg, Ca, etc.) of the above-mentioned fatty acid; Examples include dibicytin, a salt of Ba, etc.). In addition to these, higher alcohols having 12 or more carbon atoms and sulfuric esters may also be used. Moreover, commercially available general surfactants can also be used. These dispersants may be used alone or in combination of two or more. These dispersants are added in an amount of 1 to 20 parts by weight based on 100 parts by weight of the binder. As the lubricant, silicone oil, carbon black, graphite, carbon black graft polymer, molyph didene disulfide, tungsten disulfide, etc. can also be used.
これらの潤滑剤はバインダioo重量部に対して0.2
〜20重量部の範囲で添加される。 使用してもよい研
磨材としては、アルミナ、炭化ケイ素酸化クロム、コラ
ンダム等が使用される。These lubricants are 0.2 parts by weight of binder.
It is added in a range of 20 parts by weight. As the abrasive material that may be used, alumina, silicon carbide chromium oxide, corundum, etc. are used.
これらの研磨材は平均粒子径0.05〜5μの大きさの
ものが使用され、特に好ましくは、0.1〜2μである
。 これらの研磨材は結合剤100重量部に対して2〜
20重量部の範囲で添加される。 使用してもよい帯電
防止剤としては、グラファイト、カーボンブラック、酸
化スズ−酸化アンチモン系化合物、酸化スズ−酸化チタ
ン−酸化アンチモン系化合物、カーボンブラックグラフ
トポリマーなどの導電性粉末ニサボニンなどの天然界面
活性剤:アルキレンオキサイド系等のノニオン界面活性
剤:高級アルキルアミンL第4級アンモニウム塩類、ホ
スホニウムまたはスルホニウム類などのカチオン界面活
性剤:カルボン酸、スルホン酸、燐酸、硫酸エステル基
、燐酸エステル基等の酸性基を含むアニオン界面活性剤
ニアミノスルホン酸類、アミノアルコールの硫酸または
燐酸エステル類等の両性活性剤などがあげられる。These abrasives have an average particle size of 0.05 to 5 .mu.m, particularly preferably 0.1 to 2 .mu.m. These abrasives are used in an amount of 2 to 100 parts by weight of the binder.
It is added in an amount of 20 parts by weight. Antistatic agents that may be used include graphite, carbon black, tin oxide-antimony oxide compounds, tin oxide-titanium oxide-antimony oxide compounds, and natural surfactants such as Nisabonin, a conductive powder such as carbon black graft polymers. Agent: Nonionic surfactant such as alkylene oxide type: Higher alkyl amine L Cationic surfactant such as quaternary ammonium salts, phosphonium or sulfonium: Carboxylic acid, sulfonic acid, phosphoric acid, sulfuric acid ester group, phosphoric ester group, etc. Examples include anionic surfactants containing acidic groups, niaminosulfonic acids, amphoteric surfactants such as sulfuric acid or phosphoric acid esters of amino alcohols, and the like.
磁性塗料の溶媒まだは磁性塗料塗布の際に使用する溶媒
としては、一般の有機溶媒、例えば、アセトン、メチル
エチルケトン、メチルイソブチルケトン、シクロヘキサ
ノン等のケトン類:メタノール、ブタノール等のアルコ
ール類:酢酸エチル、乳酸エチル等のエステル類ニジエ
チレングリコールジメチルエーテル、テトロヒドロフラ
ン、ジオキサン等のエーテル類:トルエン、キシレン等
の芳香族炭化水素:メチレンクロライド、エチレンクロ
ライド、クロロホルム、ジクロルベンゼン等のハロゲン
化炭化水素等が使用できる。Solvents for magnetic paints Solvents used when applying magnetic paints include general organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, ketones such as cyclohexanone, alcohols such as methanol and butanol, ethyl acetate, Esters such as ethyl lactate Ethers such as diethylene glycol dimethyl ether, tetrahydrofuran, and dioxane: Aromatic hydrocarbons such as toluene and xylene: Halogenated hydrocarbons such as methylene chloride, ethylene chloride, chloroform, and dichlorobenzene are used. can.
(b)、連続薄膜型磁性層
磁性粒子がバインダなしに連続して付着し合った構造か
らなる。 使用可能な磁性粒子は、Fe、04、γ−F
ezOs、これらの中間組成のベルトライド化合物、C
o−Ni系合金、或いはこれらに各種金属を添加したも
のがある。 Hoの範囲及びその効果は上記の塗布型の
ものについて述べたと同様でちる。 形成方法として、
真空蒸着法、イオンブレーティング法、スパッタ法、メ
ッキ法等がある。 また、上記に例示した軟磁性を示す
磁性粒子も使用できる。(b) Continuous thin film magnetic layer has a structure in which magnetic particles are continuously attached to each other without a binder. Magnetic particles that can be used include Fe, 04, γ-F
ezOs, bertolide compounds of intermediate composition between these, C
There are o-Ni alloys and alloys with various metals added thereto. The range of Ho and its effects are the same as those described for the coating type. As a forming method,
There are vacuum evaporation methods, ion blating methods, sputtering methods, plating methods, etc. Furthermore, magnetic particles exhibiting soft magnetism as exemplified above can also be used.
(2)、面に垂直方向に磁化容易軸をもつ磁気記録層(
a)、塗布型磁性層
Baフェライト等のマグネトブランバイト型、Fe5O
t、γ−Fezes、Co被着γFezes、MnB1
゜Co等の磁性粒子を垂直方向に配向させる。(2), a magnetic recording layer with an axis of easy magnetization perpendicular to the plane (
a) Coated magnetic layer: magnetoblanbite type such as Ba ferrite, Fe5O
t, γ-Fezes, Co-coated γFezes, MnB1
゜Magnetic particles such as Co are oriented in the vertical direction.
(b)、連続薄膜型磁性層 これには、酸化鉄系磁性粒子をはじめ、c。(b), continuous thin film magnetic layer This includes iron oxide magnetic particles, c.
−〇r、 Co CrにRh又はMoを添加したもの
、Co −V、 Co −Ru等をスパッタ法、真空蒸
着法で被着せしめた薄膜、Co −Ni −Mn−P、
Coのメッキ膜であってもよい。-〇r, Co Cr with Rh or Mo added, Co -V, Co -Ru, etc. thin film deposited by sputtering or vacuum evaporation, Co -Ni -Mn-P,
It may also be a Co plating film.
!
また、本発明の磁気記録媒体に使用可能な基体材料は、
種々のものが採用可能である。 例えは、望ましい表面
平滑性を示す基体として、ポリエチレンテレフタレート
、ポリ塩化ビニル、三酢酸セルロース、ポリカーボネー
ト、ポリイミド、ポリアミド、ポリメチルメタクリレー
トの如きプラスチックス、ガラス等のセラミックス等か
らなる基体が使用可能である。 或いは金属基体も使用
してもよい。 基体の形状はシート、カード、ディスク
、ドラムの他、長尺テープ状でもよい。! Further, base materials that can be used in the magnetic recording medium of the present invention include:
Various types can be adopted. For example, as substrates exhibiting desirable surface smoothness, substrates made of plastics such as polyethylene terephthalate, polyvinyl chloride, cellulose triacetate, polycarbonate, polyimide, polyamide, polymethyl methacrylate, ceramics such as glass, etc. can be used. . Alternatively, metal substrates may also be used. The shape of the substrate may be a sheet, a card, a disk, a drum, or a long tape.
5、実施例
以下、本発明の磁気記録媒体を図面参照下に更に詳細に
説明する。5. Examples The magnetic recording medium of the present invention will be explained in more detail below with reference to the drawings.
第1図は、本発明による各種の磁気記録媒体を示し、図
中の矢印の向きは、磁化容易軸の向きを示す。 また、
基体6としては、ポリエチレンテレフタレート等を使用
している。FIG. 1 shows various magnetic recording media according to the present invention, and the direction of the arrow in the figure indicates the direction of the axis of easy magnetization. Also,
As the base body 6, polyethylene terephthalate or the like is used.
第1図(A)の例では、基体6上に、まず強磁性粉末(
γ−FezQa :針状比6〜8、Hc= 3500e
)をバインダ中に含有する塗布型面内磁気異方性磁気
記録層10を形成し、これを充分にカレンダー処理した
後、後述の対向ターゲットスパッタ法によってB8工(
面内方向に対し垂直方向における保磁カニ以下同じ)
=4000 e % My / MH=” 5の酸化鉄
系連続薄膜壓垂直磁気異方性磁気記録層11を形成して
いる。In the example of FIG. 1(A), ferromagnetic powder (
γ-FezQa: Acicular ratio 6-8, Hc = 3500e
) is formed in the binder, and after sufficiently calendering, B8 process (
The same applies below the coercive crab in the direction perpendicular to the in-plane direction)
A perpendicular magnetic anisotropic magnetic recording layer 11 is formed of an iron oxide-based continuous thin film having a perpendicular magnetic anisotropy of 4000 e % My / MH = 5.
第1図(B)では、1層目として、Co −Ni (C
。In FIG. 1(B), the first layer is Co-Ni (C
.
80 %、Ni 20%)を斜方蒸着法によって析出速
度800 A / seeゼaooo Xの連続薄膜型
面内磁気異方性磁気記録層12 (Ho= 3500e
)を形成し、更に2層目として、上記と同様の酸化鉄
系連続薄膜型垂直磁化膜11を形成している。A continuous thin film type in-plane magnetic anisotropic magnetic recording layer 12 (Ho = 3500e) was deposited by oblique evaporation at a deposition rate of 800
), and as a second layer, an iron oxide-based continuous thin film type perpendicularly magnetized film 11 similar to that described above is formed.
第1図(C)では、1層目を上記と同様の酸化鉄系垂直
磁化膜11で形成し、上層には上記と同様のγ−Fe
z Oa系塗布型磁気記録層10(但、Hc=4000
e)を設けている。In FIG. 1(C), the first layer is formed of the iron oxide-based perpendicular magnetization film 11 similar to that described above, and the upper layer is formed of γ-Fe similar to that described above.
z Oa-based coated magnetic recording layer 10 (Hc=4000
e).
第1図(D)においては、上記と同様の酸化鉄系垂直磁
化膜11上に、上記と同様の長手記録方式のCo−Ni
系連続薄膜12を形成している。In FIG. 1(D), a Co-Ni film of the same longitudinal recording method as above is deposited on the same iron oxide-based perpendicular magnetization film 11 as above.
A continuous thin film 12 is formed.
第1図(E)の例では、上記と同様の酸化鉄系垂直磁化
膜11上に、六方晶フェライト又はBaフェライト(平
均粒径0.1〜0.27zm)を強磁性粉末として含む
塗布型垂直磁化膜13を有している。 この塗布型垂直
磁化膜13は、上記の塗布型長手記録層10で用いたと
同じバインダに強磁性粉末を分散させ、塗布したもので
あるが、塗布後には垂直に磁場配向さぜ、乾燥処理する
。In the example of FIG. 1(E), a coated type containing hexagonal ferrite or Ba ferrite (average particle size 0.1 to 0.27 zm) as ferromagnetic powder is applied on the same iron oxide-based perpendicularly magnetized film 11 as above. It has a perpendicular magnetization film 13. This coated perpendicular magnetization film 13 is made by dispersing ferromagnetic powder in the same binder as used in the above-mentioned coated longitudinal recording layer 10 and coating it, but after coating, it is vertically aligned in a magnetic field and dried. .
第1図(F )の列では、下層11及び上層11′共に
、上記の酸化鉄系垂直磁化膜からなっている。 但、下
層11 i’l: He上= 4000e、 fviy
/MI(=’L5であるが、上層11′はI((、L=
4200s 、 My/M、n = 1−8としてい
以上の構成の磁気記録媒体を例えば磁気テープ状とし、
このうち第1図(A)〜(D)のテープについて、リン
グ型ヘッド(ギャップ0.5μm、)ラック幅100μ
m)を用いて記録/再生を行なった。In the row of FIG. 1(F), both the lower layer 11 and the upper layer 11' are made of the above-mentioned iron oxide-based perpendicular magnetization film. However, lower layer 11 i'l: He upper = 4000e, fviy
/MI(='L5, but the upper layer 11' is I((,L=
4200s, My/M, n = 1-8, and the magnetic recording medium having the above configuration is, for example, in the form of a magnetic tape,
For the tapes shown in Figures 1 (A) to (D), ring-shaped heads (gap 0.5 μm), rack width 100 μm were used.
Recording/reproduction was performed using m).
この結果を第2図及び第3図に示した。 図中の■、■
、■、■、は夫々第1図(A)、(B)、(C)、 (
D)の各テープに対応している。The results are shown in FIGS. 2 and 3. ■,■ in the diagram
, ■, ■ are shown in Figure 1 (A), (B), (C), (
It corresponds to each tape in D).
この結果によれば、特に第1図(A)、(B)のテープ
は高周波域の特性に優れており、低記録密度から高記録
密度までの広帯域で周波数特性が良好であることが分る
。 また、第1図(B)のテープは第1図(A)のテー
プよりも、第1図(D)のテープは第1図(C)のテー
プよシも夫々再生出力が大きいが、これは酸化鉄系垂直
磁化膜とは別に設ける他の磁化膜が塗布型よりも連続薄
膜型からなっている方が高出力を示すものと考えられる
。According to these results, it can be seen that the tapes shown in Figures 1 (A) and (B) in particular have excellent characteristics in the high frequency range, and have good frequency characteristics over a wide range from low recording density to high recording density. . Also, the tape in Figure 1 (B) has a larger playback output than the tape in Figure 1 (A), and the tape in Figure 1 (D) and the tape in Figure 1 (C) also have a larger playback output. It is considered that higher output is obtained when the other magnetization film provided separately from the iron oxide-based perpendicular magnetization film is a continuous thin film type than a coating type.
また、第1図(A)〜(D)のテープは面内方向及び垂
直方向に夫々磁化容易軸をもつ磁化膜の組合せからガる
ので、周波数特性が向上するが、第1図(A)、(B)
”の場合には下層に面内方向磁化膜を有していることか
ら磁気還流効果が期待でき、高記録密度、高感度、高出
力を得ることができる。 また、第1図CE)、(F)
の例では下層が垂直方向に配向性を有しているから、と
の配向方向に追随して、その上に堆積させる磁性粒子の
磁化容易軸が垂直方向に揃えられる確率が増し、このだ
めに上層の垂直配向度が向上する。Furthermore, since the tapes shown in FIGS. 1(A) to 1(D) are formed from a combination of magnetized films having easy magnetization axes in the in-plane direction and the perpendicular direction, the frequency characteristics are improved. ,(B)
In the case of ``, since the lower layer has an in-plane magnetized film, a magnetic reflux effect can be expected, and high recording density, high sensitivity, and high output can be obtained. F)
In the example, since the lower layer is oriented in the vertical direction, the probability that the axis of easy magnetization of the magnetic particles deposited on it will be aligned in the perpendicular direction increases, following the orientation direction of . The degree of vertical orientation of the upper layer is improved.
次に、下層として面内(水平)方向に磁化容易軸をもつ
磁化膜を、上層として垂直方向に磁化容易軸をもつ磁化
膜を夫々形成した磁気記録媒体を作成した。 この場合
、下層を塗布型としたものをサンプル1、連続薄膜型と
したものをサンプル2とした(但、上層はH9= fo
o Oeとなるように形成した)。 そして上層として
、Co−Cr系、アモルファスTb −Fe系、本発明
の酸化鉄系の磁化膜を設けた場合の各サンプルの垂直磁
化配向度(My/Mu)を測定したところ、第4図の如
き結果が得られた。 とれによれば、本発明に従って上
層に酸化鉄系垂直磁化膜を設けた場合、その垂直配向性
が他の材質のものよシも大幅に向上していることが分る
。 また、下層に連続薄膜型磁化膜を設けると塗布型の
ものに比べて、垂直配向度75(良くなっている。Next, a magnetic recording medium was prepared in which a magnetic film with an easy axis of magnetization in the in-plane (horizontal) direction was formed as a lower layer, and a magnetic film with an easy axis of magnetization in the vertical direction was formed as an upper layer. In this case, sample 1 was a coating type lower layer, and sample 2 was a continuous thin film type (however, the upper layer was H9 = fo
o Oe). The perpendicular magnetization orientation degree (My/Mu) of each sample was measured when a Co-Cr-based, amorphous Tb-Fe-based, or iron oxide-based magnetized film of the present invention was provided as an upper layer. The following results were obtained. According to Tore, it can be seen that when an iron oxide-based perpendicular magnetization film is provided as an upper layer according to the present invention, its perpendicular orientation is significantly improved compared to that of other materials. Further, when a continuous thin film type magnetized film is provided as the lower layer, the degree of vertical orientation is 75 (better) than that of the coated type.
なお、本発明において、上記の連続薄膜型垂直磁化膜は
、後述の対向ターゲットスパッタ法(特に酸化鉄系、B
aフェライト、基板温度300°C)をはじめ、RFス
パッタ法(列えばCo−Cr合金、Co−Cr−Rh合
金、Co−Ru合金ターゲット使用、真空度10 ’T
orr、 Arガス圧10 ’ 〜10 ’ Torr
。In the present invention, the above-mentioned continuous thin film type perpendicularly magnetized film is produced by the facing target sputtering method (especially iron oxide based, B
a-ferrite, substrate temperature 300°C), RF sputtering method (e.g. using Co-Cr alloy, Co-Cr-Rh alloy, Co-Ru alloy target, vacuum level 10'T)
orr, Ar gas pressure 10' to 10' Torr
.
堆積膜厚0.5μm)、真空蒸着法(例えばCo −C
r合金、C6−Ni−P合金の蒸発源便用、真空度1O
−1lTorr1析出速度4000 A / 5ee)
、無電解メッキ法で形成可能である。Deposited film thickness 0.5 μm), vacuum evaporation method (e.g. Co-C
For use as an evaporation source for r alloy, C6-Ni-P alloy, vacuum degree 1O
-1lTorr1 precipitation rate 4000 A/5ee)
, can be formed by electroless plating.
また、上記の塗布型水平磁化膜は、列えば次の組成の磁
性塗料を用いて6μmの塗布厚で形成してよい。Further, the above-mentioned coated horizontal magnetization film may be formed with a coating thickness of 6 μm using a magnetic paint having the following composition.
強磁性粉末(γ−’I”exOs、針状比6〜8)10
0重量部
塩化ビニル−酢酸ビニル共重合体
20重量部
ポリウレタン樹脂 8重量部レシチン
2重量部メチルエチルケトン
100重量部シクロヘキサン 100重
量部また、上記の塗布型垂直磁化膜は、強磁性粉末とし
て例えば六方晶系フェライト(平均粒径(11〜0.2
μm)を上記と同様のバインダ中に含有せしめた塗料を
塗布後、磁場配向させ、乾燥させることによって形成可
能である。Ferromagnetic powder (γ-'I''exOs, acicular ratio 6-8) 10
0 parts by weight Vinyl chloride-vinyl acetate copolymer 20 parts by weight Polyurethane resin 8 parts by weight Lecithin
2 parts by weight methyl ethyl ketone
100 parts by weight cyclohexane 100 parts by weight The coating-type perpendicularly magnetized film may be prepared using, for example, hexagonal ferrite (average particle size: 11 to 0.2) as ferromagnetic powder.
It can be formed by applying a paint containing .mu.m) in the same binder as above, aligning it in a magnetic field, and drying it.
上記の水平磁化用の連続薄膜は、斜方向蒸着等の真空蒸
着法によシ、例えば蒸発源Co −NiX 真空度1
0 ’Torr、入射角60°、析出速度800X/s
ecで形成してよい。 或いは、スパッタ法(例えばF
eタクーッ)、Ar−02雰囲気使用)で形成すること
もできる。The continuous thin film for horizontal magnetization described above is produced by a vacuum evaporation method such as oblique evaporation.
0'Torr, incidence angle 60°, deposition rate 800X/s
It may be formed using ec. Alternatively, sputtering method (for example, F
It can also be formed using an Ar-02 atmosphere.
上記の酸化鉄系垂直磁化膜を形成するために、磁性材枦
1を基体上に被着させる手段としては、磁性層構成原子
を飛翔させる真空蒸着法(電界蒸着、イオンブレーティ
ング法を含む。)、スパッタリング法等があるが、この
うち対向ターゲットスパッタ装置を用いる方法が望まし
い。In order to form the above-mentioned iron oxide-based perpendicularly magnetized film, the method for depositing the magnetic material 1 on the substrate includes a vacuum evaporation method (including electric field evaporation and ion blating method) in which atoms constituting the magnetic layer are caused to fly. ), sputtering methods, etc. Among these methods, a method using a facing target sputtering device is preferable.
第5図は、対向ターゲットスパッタ装置を示すものであ
る。FIG. 5 shows a facing target sputtering apparatus.
図面において、1は真空槽、2は真空槽1を排気する真
空ポンプ等からなる排気系、3は真空槽1内に所定のガ
スを導入してガス圧力を10−1〜10’Torr程度
に設定するガス導入系である0ターゲツト電極は、ター
ゲットホルダー4によシ一対のターゲットT□、T2を
互いに隔てて平行に対向配置した対向ターゲット電極と
して構成されている。 これらのターゲット間には、磁
界発生手段(図示せず)による磁界が形成される。 一
方、磁性薄膜を形成すべき基体6は、基体ホルダー5に
よって、上記対向ターゲット間の側方に垂直に配置され
る。In the drawing, 1 is a vacuum chamber, 2 is an exhaust system consisting of a vacuum pump etc. for evacuating the vacuum chamber 1, and 3 is an exhaust system that introduces a predetermined gas into the vacuum chamber 1 to maintain a gas pressure of about 10-1 to 10'Torr. The zero target electrode, which is the gas introduction system to be set up, is configured as a facing target electrode in which a pair of targets T□, T2 are arranged facing each other in parallel with each other, separated from each other by the target holder 4. A magnetic field is generated between these targets by magnetic field generating means (not shown). On the other hand, the substrate 6 on which the magnetic thin film is to be formed is placed perpendicularly to the side between the opposing targets by the substrate holder 5.
このように構成されたスパッタ装置(において、平行に
対向し合った両ターゲットT□、T2ρ各表面と垂直方
向に磁界を形成し、この磁界によシ陰極降下部(即ち、
ターゲットT□−T2間に発生したプラズマ雰囲気と各
ターゲラ)T□及びT2との間の領域)での電界で加速
されたスパッタガスイオンのターゲット表面に対する衝
撃で放出されたγ電子をターゲット間の空間にとじ込め
、対向した他方のターゲット方向へ移動させる。 他方
のターゲット表面へ移動したγ電子は、その近傍の陰極
降下部で反射される。 こうして、γ電子はターゲット
TI TZ間において磁界に束縛されながら往復運動
を繰返すことになる。 この往復運動の間に、γ電子は
中性の雰囲気ガスと衝突して雰囲気ガスのイオンと電子
とを生成させ、これらの生成物がターゲットからのγ電
子の放出と雰囲気ガスのイオン化を促進させる。 従っ
て、ターゲラ)T□−12間の空間には高密度のプラズ
マが形成され、これに伴なってターゲット物質が充分に
スパッタされ、側方の基体6上に磁性材料として堆積し
てゆくことになる。In the sputtering apparatus configured in this way, a magnetic field is formed in the direction perpendicular to the surfaces of both targets T□ and T2ρ facing each other in parallel, and this magnetic field creates a cathode fall section (i.e.
The γ electrons emitted by the impact of the sputtering gas ions on the target surface, which are accelerated by the plasma atmosphere generated between targets T□ and T2 and the electric field in each target layer (area between T□ and T2), are transferred between the targets. Lock it in space and move it towards the other target. The γ electrons that have moved to the other target surface are reflected at the cathode fall section nearby. In this way, the γ electrons repeatedly move back and forth between the targets TI and TZ while being bound by the magnetic field. During this reciprocating motion, the γ electrons collide with the neutral atmospheric gas to generate ions and electrons of the atmospheric gas, and these products promote the release of γ electrons from the target and the ionization of the atmospheric gas. . Therefore, a high-density plasma is formed in the space between the target layer T□-12, and the target material is sufficiently sputtered and deposited as a magnetic material on the side substrate 6. Become.
この対向ターゲットスパッタ装置は、他の飛翔手段に比
べて、高速スパッタによる高堆積速度の製膜が可能であ
シ、また基体がプラズマに直接曝されることがなく、低
い基体温度での製膜が可能である等のことから、垂直磁
化膜を形成するのに有利である。 しかも、対向ターゲ
ット間ノ(ツタ装置によって飛翔した磁性膜材料の基板
への入射エネルギーは、通常のスパッタ装置のものより
も小さいので、材料が所望の方向へ方向性を以って堆積
し易く、垂直磁化記録に適した構造の膜を得易くなる。Compared to other flying methods, this facing target sputtering device is capable of forming films at high deposition rates through high-speed sputtering, and the substrate is not directly exposed to plasma, allowing film formation at low substrate temperatures. This method is advantageous for forming a perpendicularly magnetized film. Moreover, since the energy incident on the substrate of the magnetic film material that is ejected by the ivy device between the opposing targets is smaller than that of a normal sputter device, the material is easily deposited directionally in the desired direction. It becomes easier to obtain a film with a structure suitable for perpendicular magnetization recording.
次に、上記のスパッタ装置を用いて磁気記録媒体を作成
する具体例を説明する。Next, a specific example of producing a magnetic recording medium using the above sputtering apparatus will be described.
この作成条件は以下の通りで6つだ。There are six conditions for this creation as follows.
ターゲツト材 鉄(Coを1原子チ含有)基体
ガラス
対向ターゲット間隔 10011=
スパツタ空間の磁界 1000e
ターゲツト形状 100郡直径の円盤(5目厚)基
体とターゲット端との間隔 30簡
真空槽内の背圧 10 ’ Torr導入ガス
Ar 十Ox
導入ガス圧 4 X 10 ” Torrスパッタ
投入電力 420W
このようにしてベース6上に酸化鉄系の磁気記録層を有
する+m磁気記録媒体得られた。 この磁気記録層の特
性評価は、X線マイクロアナライザによって行なった。Target material Iron (contains 1 atom of Co) base
Distance between glass facing targets 10011 = Magnetic field in sputtering space 1000e Target shape Disc with diameter of 100 (5 mesh thickness) Distance between substrate and target end Back pressure in 30mm vacuum chamber 10' Torr Introduced gas
Ar 10Ox Introduced gas pressure 4 X 10'' Torr Sputter input power 420 W In this way, a +m magnetic recording medium having an iron oxide magnetic recording layer on the base 6 was obtained.The characteristics of this magnetic recording layer were evaluated by It was performed using a line microanalyzer.
得られた上記磁気記録層の特性は次の如くであった。The properties of the obtained magnetic recording layer were as follows.
まず、面内方向での残留磁化量(Mrr )と面に垂直
方向での残留磁化量(MV )との比はMv/MII≧
0.5であった。即ち、第6図に例示するように、破線
で示す面内方向での磁化時のヒステリシス曲線と、実線
で示す垂直方向での磁化時のヒステリシス曲線とが夫々
得られたが、印加磁界がゼロのときの各磁化量をMH,
Mvとした。 これによれば、前者のヒステリシス曲線
は後者のヒステリシス曲線よシも小さく、Mv≧0.5
MHとなっていることが明らかであシ、垂直磁化にとっ
て好適な磁気記録層が形成されていることが分る。 こ
れは、酸化鉄系の磁性層においては驚ぐべき事実である
。First, the ratio of the residual magnetization in the in-plane direction (Mrr) to the residual magnetization in the perpendicular direction (MV) is Mv/MII≧
It was 0.5. That is, as illustrated in FIG. 6, a hysteresis curve during magnetization in the in-plane direction shown by the broken line and a hysteresis curve during magnetization in the perpendicular direction shown by the solid line were obtained, but when the applied magnetic field is zero The amount of magnetization when MH,
Mv. According to this, the former hysteresis curve is smaller than the latter hysteresis curve, and Mv≧0.5
It is clear that the magnetic field is MH, and a magnetic recording layer suitable for perpendicular magnetization is formed. This is a surprising fact for iron oxide-based magnetic layers.
また、この磁気記録層の組成をXMA (X線マイクロ
アナライザ:日立製作所rX−556JKEVEX−7
000型)で測定したところ、Feが主ピークであl)
、Coが少量含まれていることが分った。In addition, the composition of this magnetic recording layer was measured using XMA (X-ray microanalyzer: Hitachi rX-556JKEVEX-7
When measured with 000 type), Fe was the main peak.
, Co was found to be contained in small amounts.
更に、酸化鉄の状態を調べるために、X線回折装置(日
本電子社製r JDX −10RA J :CuKα管
球使用)を用いて測定したところ、下記表に示すように
、磁性層が酸化鉄を主成分とするものであることが分っ
た。 しかも、この磁気記録層は、面内方向に対して垂
直方向に秩序圧しい構造を有していることが電子顕微鏡
で観察された。Furthermore, in order to investigate the state of iron oxide, measurements were performed using an X-ray diffraction device (JEOL r JDX-10RA J: using a CuKα tube), and as shown in the table below, it was found that the magnetic layer was iron oxide. It was found that the main component is Furthermore, it was observed using an electron microscope that this magnetic recording layer had an ordered structure in the direction perpendicular to the in-plane direction.
なお、上記のスパッタ法にょる製膜前に、基体上の表面
を同一スパッタ装置内でAr+にょシボンバードして表
面清浄化処理したシ、或いはベーキングを施すか、高周
波をかけて表面処理しておくのが望ましい。In addition, before forming the film by the above sputtering method, the surface of the substrate is cleaned by bombarding with Ar+ in the same sputtering device, or by baking, or by applying high frequency to the surface. is desirable.
次に、本発明による磁気記録媒体は、磁性層として酸化
鉄を主成分とするものを用いているので、従来のCo
−Cr系磁性層に比べて化学的、機械的安定性等に著し
く!れている。 第7図は、8o0c185%RHで強
制劣化試験を行なった場合に得られた、酸化鉄系磁性層
を用いた本発明による媒体の、試料振動型磁力計(東英
工業社製)で測定した残留磁束密度(Br)の経時変化
(a)と、Co −Cr系磁性層を用いた媒体の残留磁
束密度(Br)の経時変化(b)とを示すものである(
△Brは残留磁束密度の変化量)。 とれによれば、酸
化鉄系磁性層では、Co −Cr系磁性層よl) Br
の劣化が大幅に小さくなることが分る。 なお、酸化鉄
系磁性層で△Br/Brが幾分低下しているのは、膜の
組成であるFea04の一部がγ−Fe2esに移行し
たからであると考えられる。 また、1力月(30日)
後の観察結果において、Co−0r系磁性層の表面に斑
点、くもシ、サビ等が生じていたが、酸化鉄系磁性層で
は表面状態に変化はみられなかった。Next, since the magnetic recording medium according to the present invention uses a magnetic layer containing iron oxide as a main component, it is different from the conventional Co
- Significant chemical and mechanical stability compared to Cr-based magnetic layers! It is. Figure 7 shows the sample measured with a vibrating magnetometer (manufactured by Toei Kogyo Co., Ltd.) of the medium according to the present invention using an iron oxide magnetic layer obtained when a forced deterioration test was conducted at 8 o 0 c 185% RH. It shows the change over time in the residual magnetic flux density (Br) (a) and the change over time in the residual magnetic flux density (Br) of a medium using a Co-Cr magnetic layer (b).
△Br is the amount of change in residual magnetic flux density). According to Tore, in the iron oxide magnetic layer, the Co-Cr magnetic layer is better than the Co-Cr magnetic layer.
It can be seen that the deterioration is significantly reduced. Note that the reason why ΔBr/Br decreases somewhat in the iron oxide magnetic layer is considered to be because a part of Fea04, which is the composition of the film, has shifted to γ-Fe2es. Also, 1 month (30 days)
In the subsequent observation results, spots, spiders, rust, etc. were observed on the surface of the Co-0r based magnetic layer, but no change was observed in the surface condition of the iron oxide based magnetic layer.
また、公知のTh −Fe系磁気記録層について、上記
と同様の劣化試験を行なったところ、第7図に破線Cで
示す結果が得られた。 Th −Fe系では、経時変化
が激しく、5日程度で磁性が殆んど消失してしまい、特
性不良となることが分る。Further, when a deterioration test similar to the above was conducted on a known Th--Fe magnetic recording layer, the results shown by the broken line C in FIG. 7 were obtained. It can be seen that in the Th-Fe system, the change over time is severe, and most of the magnetism disappears in about 5 days, resulting in poor characteristics.
次に、本発明による磁気記録媒体において、磁気記録層
(上下2層)の各種組合せをまとめて下記表に示す。Next, in the magnetic recording medium according to the present invention, various combinations of the magnetic recording layers (upper and lower layers) are summarized in the table below.
上記表中、
↑:磁化容易軸が垂直方向
→:磁化容易軸が面内(水平)方向
◎二酸化鉄系垂直磁化膜
○:従来の連続薄膜型磁化膜
ロ:従来の塗布型磁化膜
を表わす。 本発明では、上下2層の組合せによりて、
上記表に示した9種類の構造を形成可能であるが、その
うち、酸化鉄系垂直磁化膜が上層(表面側)に存在して
いる煮1、A2、IG、 5、煮7、A9の媒体が、経
時変化、耐摩耗性、磁気ヘッドとの接触性等の面で望ま
しい。In the above table, ↑: The axis of easy magnetization is vertical →: The axis of easy magnetization is in the in-plane (horizontal) direction ◎ Iron dioxide-based perpendicularly magnetized film ○: Conventional continuous thin-film magnetized film B: Conventional coated magnetized film . In the present invention, by combining the upper and lower layers,
It is possible to form the nine types of structures shown in the table above, but among these, medium 1, A2, IG, 5, 7, and A9 have an iron oxide-based perpendicular magnetization film on the upper layer (surface side). However, it is desirable in terms of aging, wear resistance, contactability with the magnetic head, etc.
なお、本発明は、磁気記録層が3層以上あり、その少な
くとも1層が酸化鉄系垂直磁化膜カニらなる媒体にも適
用可能である。Note that the present invention is also applicable to a medium having three or more magnetic recording layers, at least one of which is an iron oxide-based perpendicularly magnetized film.
図面は本発明を例示するものであって、第1図(A)、
(B)、(C)、(D)、(E)、(F) は各種磁
気記録媒体の各断面図、第2図及び第3図は各種磁気記
録媒体の再生特性を示す各グラフ、
第4図は各種磁気記録層によるその垂直配向度を示すグ
ラフ、
第5図は対向ターゲットスパッタ装置の概略断面図、
第6図は磁気記録媒体のヒステリシス曲線図、第7図は
磁気記録媒体の残留磁束密度の経時変化を比較して示す
グラフ
である。
なお、図面に示された符号において、
1・・・・・・・・・・・・・・・・・・真空槽2・・
・・・・・−・・・・・・・・・・排気系3・・・・・
・・・・・・−・・・・・ガス導入系4.5・・・・・
・・・・ホルダー
6・・・・・・−・・・・・・・・・・・基体10、1
3・・・・・・塗布型磁気記録層11.11’・・−・
・・酸化鉄系連続薄膜型磁気記録層12・・・・・・・
・・・−・・・・・・・連続薄膜型磁気記録層T1、T
2−・・・・・・・シーゲットである。
代理人 弁理士 逢 坂 宏(他1名)第1図
第2図
第3図The drawings illustrate the present invention, and include FIG. 1(A),
(B), (C), (D), (E), and (F) are cross-sectional views of various magnetic recording media, and Figures 2 and 3 are graphs showing the reproduction characteristics of various magnetic recording media. Figure 4 is a graph showing the degree of perpendicular orientation of various magnetic recording layers, Figure 5 is a schematic cross-sectional view of a facing target sputtering device, Figure 6 is a hysteresis curve diagram of a magnetic recording medium, and Figure 7 is a graph showing the residual degree of magnetic recording medium. It is a graph showing a comparison of changes in magnetic flux density over time. In addition, in the symbols shown in the drawings, 1......Vacuum chamber 2...
・・・・・・-・・・・・・・・・Exhaust system 3・・・・・・
・・・・・・-・・・・・・Gas introduction system 4.5・・・・・・
・・・・Holder 6・・・・・・−・・・・・・・・・・Base 10, 1
3... Coated magnetic recording layer 11.11'...
...Iron oxide-based continuous thin film magnetic recording layer 12...
・・・-・・・・・・Continuous thin film magnetic recording layer T1, T
2- It is Seaget. Agent: Patent attorney Hiroshi Aisaka (and 1 other person) Figure 1 Figure 2 Figure 3
Claims (1)
気記録層が、 (a)、酸化鉄を主成分とする連続磁性層からなってい
ること。 (b)、磁性層の面内方向での残留磁化(MW)と、磁
性層の面に対し垂直方向での残留磁化(MV)との比(
Mv / MW )が0.5以上であること。 を夫々構成として具備することを特徴とする磁気記録媒
体。[Scope of Claims] 1. It has a plurality of magnetic recording layers, and at least one magnetic recording layer is (a) composed of a continuous magnetic layer containing iron oxide as a main component. (b), the ratio of the residual magnetization (MW) in the in-plane direction of the magnetic layer to the residual magnetization (MV) in the direction perpendicular to the plane of the magnetic layer (
Mv/MW) is 0.5 or more. What is claimed is: 1. A magnetic recording medium comprising:
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP58031939A JPS59157838A (en) | 1983-02-28 | 1983-02-28 | Magnetic recording medium |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP58031939A JPS59157838A (en) | 1983-02-28 | 1983-02-28 | Magnetic recording medium |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS59157838A true JPS59157838A (en) | 1984-09-07 |
JPH0315247B2 JPH0315247B2 (en) | 1991-02-28 |
Family
ID=12344935
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP58031939A Granted JPS59157838A (en) | 1983-02-28 | 1983-02-28 | Magnetic recording medium |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS59157838A (en) |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5026506A (en) * | 1973-07-07 | 1975-03-19 | ||
JPS52134706A (en) * | 1976-05-06 | 1977-11-11 | Univ Tohoku | Vertical magnetic recorder reproducer and system therefor |
JPS5434205A (en) * | 1977-08-22 | 1979-03-13 | Canon Inc | Magnetic recording medium |
JPS5451810A (en) * | 1977-09-30 | 1979-04-24 | Shiyunichi Iwasaki | Magnetic recording regenerative apparatus |
JPS57158380A (en) * | 1981-03-26 | 1982-09-30 | Teijin Ltd | Counter target type sputtering device |
-
1983
- 1983-02-28 JP JP58031939A patent/JPS59157838A/en active Granted
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5026506A (en) * | 1973-07-07 | 1975-03-19 | ||
JPS52134706A (en) * | 1976-05-06 | 1977-11-11 | Univ Tohoku | Vertical magnetic recorder reproducer and system therefor |
JPS5434205A (en) * | 1977-08-22 | 1979-03-13 | Canon Inc | Magnetic recording medium |
JPS5451810A (en) * | 1977-09-30 | 1979-04-24 | Shiyunichi Iwasaki | Magnetic recording regenerative apparatus |
JPS57158380A (en) * | 1981-03-26 | 1982-09-30 | Teijin Ltd | Counter target type sputtering device |
Also Published As
Publication number | Publication date |
---|---|
JPH0315247B2 (en) | 1991-02-28 |
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