JPS60107727A - Magnetic recording medium - Google Patents

Abstract

PURPOSE:To provide a decrease in noise, increase in signal output and consequently remarkable improvement in S/N by providing the 1st magnetic layer which has the axis of easy magnetization in the in-plane direction of a base and of which the axis of easy magnetization is isotropic and the 2nd magnetic layer consisting of a thin ferromagnetic metallic film which has the axis of easy magnetization in the direction perpendicular to the base surface. CONSTITUTION:The 1st magnetic layer 2 which has the axis of easy magnetization in the in-plane direction of a base 1 and of which the axis of easy magnetization is isotropic is disposed on the main plane under a base. The 2nd magnetic layer 3 consisting of a thin ferromagnetic metallic film having the axis of easy magnetization in the direction perpendicular to the plane of the base 1 is disposed on the layer 2. The 1st magnetic layer is preferably isotropic and either of the resin layer dispersed and fixed with ferromagnetic fine particles or the thin magnetic iron oxide film is suitable. Co alloys such as Co-Cr, Co-V, Co-Mo, Co-W, Co-Ru, Co-Ni-Cr are suitable for the 2nd magnetic layer and the coercive force thereof is preferably the same as or higher than the coercive force of the 1st magnetic layer.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は広帯域の信号記録再生に適した磁気記録媒体に
関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording medium suitable for recording and reproducing broadband signals.

従来例の構成とその問題点 回転磁気ヘッドによるヘリカル走査方式による音声１画
像の記録再生を行う技術は磁気記録の中でも最も高密度
記録化が進んでいる。Conventional Structure and Problems The technology for recording and reproducing one image of audio using a helical scanning method using a rotating magnetic head is one of the most advanced types of magnetic recording in terms of high-density recording.

更に記録密度を高めていくＫは、新しい磁気記録媒体と
磁気ヘッドの組み合せが必要であるが、本質的に信号処
理の面から、最短記録波長は短かくなるが、信号の周波
数帯域としてはおよそ最短記録波長の約１０倍の記録波
長まで望まれるので、磁気記録媒体の設計もこの点に配
慮が必要不可欠となる。K, which further increases the recording density, requires a new combination of magnetic recording medium and magnetic head, but essentially from the standpoint of signal processing, the shortest recording wavelength becomes shorter, but the signal frequency band is approximately Since a recording wavelength of about 10 times the shortest recording wavelength is desired, it is essential to take this point into consideration when designing a magnetic recording medium.

従来の磁気記録媒体が本質的に短波長域の特性限界を有
していることは良く知られている事実である。これは従
来の磁気記録媒体は媒体長手方向の残留磁化を利用する
ものであり、記録が短波長になるｔなど媒体内部の自己
減磁界が増大し、更に媒体内部エネルギーが最小になる
よう磁化ベクトルの回転が生じ、それらが急激な再生出
力低下として現れるためである。It is a well-known fact that conventional magnetic recording media inherently have characteristic limits in the short wavelength region. This is because conventional magnetic recording media utilize residual magnetization in the longitudinal direction of the medium, and the self-demagnetizing field inside the medium increases when the recording wavelength becomes short, and the magnetization vector is adjusted so that the internal energy of the medium is minimized. This is because rotations occur, which appear as a sudden drop in reproduction output.

自己減磁界の影響をできる限り小さくするだめの最も一
般的な方法は、自己減磁界に打ち勝つように媒体の保磁
力を大きくすることである。しかしこの方法は媒体厚さ
方向への磁化浸透を減するように働くため長波長出力の
低下を招くか、或いは磁束密度の非常に大きい消去、記
録ヘッドが要求されることになり、消費電力の増大につ
ながり媒体コストの上昇と共に、ヘッドの高価格化をき
だす。The most common way to minimize the effects of the self-demagnetizing field is to increase the coercive force of the medium to overcome the self-demagnetizing field. However, this method works to reduce magnetization penetration in the media thickness direction, resulting in a decrease in long wavelength output, or requires erasing and recording heads with extremely high magnetic flux density, which reduces power consumption. This leads to an increase in the cost of the medium and the price of the head.

そこで支持体」二に比較的低保磁力の第１磁性層。Therefore, a first magnetic layer having a relatively low coercive force is used as a support.

例えばγ−Ｆ　ｅ　２０　ｓ　剣状粒子を結合剤と共に
塗布配向乾燥した層を形成し、その上に第２磁性層。For example, a layer of γ-F e 20 s sword-shaped particles is coated with a binder, oriented and dried, and a second magnetic layer is formed thereon.

例えばγ−Ｆ　ｅ　２０３　針状粒子をＣｒ　Ｏ２に置
き換えた層を形成する二層構造の磁気記録媒体が考案さ
れ、既に実用に供されている。For example, a magnetic recording medium with a two-layer structure in which the acicular particles of γ-Fe 203 are replaced with Cr O 2 has been devised and is already in practical use.

最近では塗布型磁性層上に強磁性金属薄膜層を蒸着した
二層構造のものもオーディオ用途に実用化されている。Recently, a two-layer structure in which a ferromagnetic metal thin film layer is deposited on a coated magnetic layer has also been put into practical use for audio applications.

この構造によれば、短波長側の特性改善は若干認められ
るが、基本的に受手磁化に頼っているため依然として広
帯域媒体としてはまだまだ不十分であった。According to this structure, some improvement in characteristics on the short wavelength side was observed, but it was still insufficient as a broadband medium because it basically relied on receiver magnetization.

その他にも、実用化はされていないが、二層構造体によ
る改良提案がなされている。Other improvements have been proposed using a two-layer structure, although they have not been put into practical use.

例えば特開昭５４−１４５１０５号公報では、主たる磁
気異方性軸が支持体に平行な第１磁性体層」二に、支持
体面に垂直な方向に磁気異方性軸を有する第２磁性体を
形成し、保磁力を限定することでへ、ドの作る磁界に適
合化を図ることが提案されているが、基本的に情報の担
い手が第１磁性体層であり、自己減磁界の大きい長手磁
化であることから短波長特性はやはり十分ではない。For example, in JP-A-54-145105, a first magnetic layer whose main magnetic anisotropy axis is parallel to the support, and a second magnetic layer whose main magnetic anisotropy axis is perpendicular to the support surface. It has been proposed to adapt the magnetic field created by the magnetic field by forming a magnetic field and limiting the coercive force, but basically the information carrier is the first magnetic layer, and the self-demagnetizing field is large. Since the magnetization is longitudinal, the short wavelength characteristics are still not sufficient.

特公昭４０−５３５１号公報でも塗布磁性層で類似の組
み合わせが提案されているが、垂直配向時に夕１状粒子
を核にした突起で表面が荒れるため、これによるスペー
シングロスが生じて、結果的に短波長の改善は十分行え
得ない。A similar combination of coated magnetic layers has been proposed in Japanese Patent Publication No. 40-5351, but when vertically aligned, the surface is roughened by protrusions with 1-shaped particles as nuclei, resulting in spacing loss. Therefore, it is not possible to sufficiently improve short wavelengths.

発明の目的 本発明は上記従来の間頭点を解消するもので、広帯域で
且つリング型磁気ヘッドでの記録再生特性にすぐれた磁
気記録媒体を提供することである。OBJECTS OF THE INVENTION The present invention solves the problems of the prior art, and provides a magnetic recording medium with a wide band and excellent recording and reproducing characteristics with a ring-type magnetic head.

発明の構成 本発明は支持体上に、その支持体の面内方向に磁化容易
軸を有すると共にその磁化容易軸が等方向である第１の
磁性層と、その第１の磁性層−にに前記支持体面と垂直
な方向に磁化容易軸を有する強磁性金属薄膜から成る第
２の磁性層とを備えた磁気記録媒体であり、広帯域の信
号記録再生特性に優れたものである。Structure of the Invention The present invention comprises a first magnetic layer on a support, which has an easy axis of magnetization in the in-plane direction of the support and whose easy axis of magnetization is equidirectional; This magnetic recording medium includes a second magnetic layer made of a ferromagnetic metal thin film having an axis of easy magnetization perpendicular to the support surface, and has excellent broadband signal recording and reproducing characteristics.

実施例の説明 以丁本発明の実施例について、図面を参照しながら説明
する。DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will now be described with reference to the drawings.

図は本発明の実施例における磁気記録媒体の基本構成を
示す図である。図において、１は支持体で、支持体１の
主面上には支持体１の面内方向に磁化容易軸を有すると
共に、その磁化容易軸が等方向である第１の磁性層２が
配されている。第１の磁性層２上には支持体１０面と垂
直な方向に磁化容易軸を有する強磁性金属薄膜からなる
第２の磁性層３が配されている。The figure is a diagram showing the basic configuration of a magnetic recording medium in an embodiment of the present invention. In the figure, 1 is a support, and on the main surface of the support 1 is disposed a first magnetic layer 2 which has an axis of easy magnetization in the in-plane direction of the support 1 and whose easy axes of magnetization are in the same direction. has been done. A second magnetic layer 3 made of a ferromagnetic metal thin film having an axis of easy magnetization in a direction perpendicular to the surface of the support 10 is disposed on the first magnetic layer 2 .

本発明は前記した従来の媒体の欠点に鑑みなされたもの
で、特に高密度記録時に、トラック幅を狭くすると増え
るノイズが、媒体構成要因の異方性に原因があり、特に
第１の磁性層が支配的であることを尽きとめ本発明を完
成させたものである。The present invention was developed in view of the above-mentioned drawbacks of conventional media, and the noise that increases when the track width is narrowed, especially during high-density recording, is caused by the anisotropy of the media's constituent factors, especially in the first magnetic layer. The present invention has been completed by eliminating the predominance of

本発明に用いることの出来る支持体としては、ポリエチ
レンテレフタレート等のポリエステル類。Supports that can be used in the present invention include polyesters such as polyethylene terephthalate.

ポリプロピレン等のポリオレフィン類、セルロースジア
セテート、ニトロセルロース等のセルロース”ｓＡ４体
、ポリカーボネート、ポリ塩化ビニル。Polyolefins such as polypropylene, cellulose "sA4" such as cellulose diacetate, nitrocellulose, polycarbonate, polyvinyl chloride.

芳香族ポリアミド、ポリイミド等が挙げられる。Examples include aromatic polyamide and polyimide.

本発明に用いることの第１の磁性層は等方向であれば良
く、強磁性微粒子を分散固定した樹脂層か酸化鉄磁性薄
膜のいずれかが適している。The first magnetic layer used in the present invention only needs to be equidirectional, and is suitably either a resin layer in which fine ferromagnetic particles are dispersed and fixed, or an iron oxide magnetic thin film.

前者の樹脂層は、磁気塗料を公知の塗布材により塗布乾
燥したものであって厚みは２８面程度あれば充分である
。飽和磁束密度Ｂｓば１２ｏｏ〔Ｇ〕から４ｏｏｏ［Ｇ
］、保磁力は６００〔○ｅ〕から１５ｏＯ〔Ｏｅ〕の範
囲にあれば良い。第１の磁性層の１１４成はＣＯをドー
プしたγ−Ｆｅ　○　微粒子やＣｒ　Ｏ２３ 微粒子２合金微粒子等の磁性粉末の中から選んだ磁性粉
末を、塩化ビニル系共重合体、繊維素糸（Ｉｔ１脂、ブ
チラール系樹脂、ポリウレタン系樹脂舌から選ばれた１
種又は２種以上の結合剤、溶剤、希釈剤９分散剤、と必
要に応じて潤滑剤、研暦剤を加えて得られた磁気塗料は
極力分散度をあげて支持体」二に例えばグラビアコータ
、リバースロースコータ等に塗布固定し、充分乾燥させ
て得られる。The former resin layer is made by applying and drying a magnetic coating material using a known coating material, and a thickness of about 28 layers is sufficient. Saturation magnetic flux density Bs from 12oo[G] to 4ooo[G
], the coercive force may be in the range of 600 [○e] to 15oO [Oe]. The 114 composition of the first magnetic layer is a magnetic powder selected from magnetic powders such as CO-doped γ-Fe○ fine particles and CrO23 fine particles 2 alloy fine particles, and a vinyl chloride copolymer, fiber yarn (It1 1 selected from fat, butyral resin, and polyurethane resin tongue
The magnetic paint obtained by adding a seed or two or more binders, a solvent, a diluent, a dispersant, and, if necessary, a lubricant and an abrasive agent, is used to increase the degree of dispersion as much as possible and use it as a support, for example, for gravure. It is obtained by coating and fixing on a coater, reverse-roll coater, etc., and thoroughly drying it.

第１の磁性層の第２の構成例としてはγ−Ｆｅ２Ｏ３か
Ｆｅ３Ｏ４のいずれかの強磁性薄膜が挙げられる。A second example of the structure of the first magnetic layer is a ferromagnetic thin film of either γ-Fe2O3 or Fe3O4.

これらの薄膜の形成法は、酸素を含む真空中での反応性
蒸着１反応性イオンブレーティング、反応性スパッタリ
ング法のうちのいずれかの方法単独或いは、熱処理との
組み合わせによる。The method for forming these thin films is one of reactive vapor deposition, reactive ion blating, and reactive sputtering in a vacuum containing oxygen, either alone or in combination with heat treatment.

第１の磁性層上に配される支持体面と垂直な方向に磁化
容易軸を有する強磁性金属薄膜からなる第２の磁性層は
、Ｃｏ−Ｃｘ　、Ｃｏ−Ｖ、Ｃｏ　−Ｍｏ　。The second magnetic layer made of a ferromagnetic metal thin film having an axis of easy magnetization in a direction perpendicular to the surface of the support disposed on the first magnetic layer is Co-Cx, Co-V, Co-Mo.

Ｃｏ−Ｗ、Ｃｏ−Ｒｕ、Ｃｏ−Ｎｉ−Ｃｒ等のＣＯ系合
金が適しており、保磁力は、第１の磁性層と同一かそれ
以上であることが好ましい。飽和磁束密度Ｂｓは２５ｏ
Ｏ〔Ｇ〕から４５００（Ｇ）、厚みは０．０５μｍから
０．２μｍ好ましくは０．０５μｍから０．１μｍの範
囲に設定される。かかるＣＯ系合金の薄膜の形成法は電
子ビーム蒸着法、イオンブレーティング法、スパッタリ
ング法、無電解メ１．キ法等が挙げられる。A CO-based alloy such as Co-W, Co-Ru, Co-Ni-Cr is suitable, and the coercive force is preferably the same as or greater than that of the first magnetic layer. Saturation magnetic flux density Bs is 25o
O [G] to 4500 (G), and the thickness is set in the range of 0.05 μm to 0.2 μm, preferably 0.05 μm to 0.1 μm. Methods for forming such thin films of CO-based alloys include electron beam evaporation, ion blating, sputtering, and electroless methods. Examples include the Ki method.

尚本発明の磁気記録媒体は磁気テープを中心に詳説する
ものの、他の形態２例えばディスク、シート状での実施
を拒むものではない。Although the magnetic recording medium of the present invention will be described in detail with a focus on a magnetic tape, implementation in other forms such as disks and sheets is not prohibited.

本発明の磁気記録媒体は磁気ヘッドの発生する磁界から
みて、磁気ヘッドに近い側に短波長での自己減磁損失の
殆んどない垂直方向に磁化される第２の磁性層があり、
遠い位置には中波長からし波長に適した等方向な第１の
磁性層があるため記録効率が良い。ここで波長域区分は
便宜的なもので、短波長域を１μｍ以下、中波長域を１
〜３μｍ。The magnetic recording medium of the present invention has a second magnetic layer magnetized in the perpendicular direction with almost no self-demagnetization loss at short wavelengths on the side closer to the magnetic head when viewed from the magnetic field generated by the magnetic head,
Since there is a first magnetic layer at a far position that is isotropic and suitable for medium to medium wavelengths, the recording efficiency is good. The wavelength range classification here is for convenience; the short wavelength range is 1 μm or less, and the medium wavelength range is 1 μm or less.
~3 μm.

長波長域を３μｍ以上の記録波長でわけているが、あく
まで目安である。Although the long wavelength region is divided into recording wavelengths of 3 μm or more, this is only a guideline.

第１の磁性層は等方向であるからヘッド磁界の水平成分
、垂直成分によく順応するので記録効率は従来知られて
いる２層構成の第１磁性層のいず・れよりも良好である
。Since the first magnetic layer is equidirectional, it adapts well to the horizontal and vertical components of the head magnetic field, so the recording efficiency is better than any of the conventional two-layer first magnetic layers. .

磁気記録媒体上の残留磁化により、再生磁気ヘッドを励
磁すｂ場合を考察すると、第１の磁性層の発生する磁束
は第２の磁性層が垂直方向に磁化容易軸のある磁石の集
団であるため、磁気ヘッドに向う磁界を相互作用により
強め合うので、再生効率も良好となる。Considering the case where the reproducing magnetic head is excited by the residual magnetization on the magnetic recording medium, the magnetic flux generated by the first magnetic layer is a group of magnets whose easy axis of magnetization is perpendicular to the second magnetic layer. Therefore, the magnetic fields directed toward the magnetic head are strengthened by interaction, and the reproduction efficiency is also improved.

これまでは記録、再生の信号出力面について述べたが、
磁気記録媒体としては、ノイズの低いことも極めて重要
である。So far, we have talked about the signal output side for recording and playback, but
Low noise is also extremely important for magnetic recording media.

特にトラック幅が狭くなると、ノイズが低くないと、シ
ステムとして確保すべき信号対雑音比（以後Ｓ／Ｎで示
す）を得ることができなくなるが、従来の媒体の第１の
磁性層の異方性が磁気的な不均一性を生むために、記録
波長が短かいところで、ノ、イズが急激に大きくなるこ
とが本発明では全くみられないの、で、良好なＳ／Ｎが
得られるのである。In particular, as the track width becomes narrower, it becomes impossible to obtain the signal-to-noise ratio (hereinafter referred to as S/N) required for the system unless the noise is low. In the present invention, there is no sudden increase in noise at short recording wavelengths due to magnetic non-uniformity, and a good S/N ratio can be obtained. .

又、第２の磁性層の変調ノイズも磁性層厚みが薄いので
実用上問題にならないので、全体としても狭トラツク化
にも適した媒体といえる。Moreover, the modulation noise of the second magnetic layer does not pose a practical problem because the thickness of the magnetic layer is thin, so that the medium as a whole is suitable for narrowing the track.

以下に本発明のさらに具体的な実砲例を説明する。More specific examples of actual guns of the present invention will be described below.

本発明に基ずく構造の磁気記録媒体の試作例と特性を表
に示した。Examples of prototypes and characteristics of magnetic recording media having a structure based on the present invention are shown in the table.

製法については後述した方法によった。The manufacturing method was as described below.

Ｓ／Ｎは夫々の媒体を８ＷＩＩＩ１幅の磁気テープとし
て試作したビデオテープレコーダで実測し、色信号と輝
１を信号の両者で比較した。トラ・ツク１隔は１０μｍ
とし、磁気へ、フドはギヤ、ノブ長０．２６μｍのアモ
ルファス合金へ・フドを用い、磁気テープとの相対速度
は３．８ＴｒＬ／ｓｅＣで色信号周波数は０．８Ｍ１ｂ
。The S/N was measured using a prototype video tape recorder using an 8WIII1 width magnetic tape for each medium, and the color signal and brightness 1 were compared for both signals. The distance between each tiger and Tsuk is 10μm
The magnetic head is a gear, the lid is an amorphous alloy with a knob length of 0.26 μm, the relative speed with the magnetic tape is 3.8 TrL/sec, and the color signal frequency is 0.8 M1b.
.

輝度信は周波数は５　Ｍ＋−１ｚとした場合である。The brightness signal is obtained when the frequency is 5M+-1z.

支持体は厚み８μｍ表面粗さ１００人の芳香族ポリアミ
ドを用いた。The support was made of aromatic polyamide with a thickness of 8 μm and a surface roughness of 100 μm.

以　下　余　白 ；）口述の表に示した磁気テープの製法について簡単に
説明する。Margin below;) I will briefly explain the manufacturing method of the magnetic tape shown in the table of the oral presentation.

■　平均２５０人の球状微粒子からなる磁性粉末を８０
重量部（以下単に「部」　と記す）塩化ビニル舎酢酸ビ
ニルービニルアルコール共重合体１２部、アクリロニト
リル・ブタジェン共重合体８部、ンクロヘキサノン・メ
チルイソブチルケトン混合溶剤（混合比１：１）１００
部から成る塗料成分をボールミル中で７２時間混合分散
させて磁気塗料を調製し、グラビアコータで夫々乾燥時
の厚みが所定の厚みになるよう塗布、乾燥し、８０℃の
ロールによるロール圧着法でカレンダ処理しくロール圧
力ば８８　Ｋｙ　／　ｃａｒ　）平均表面粗さ８ｏ八、
最大粗さ５００人に制御した。■ 80 pieces of magnetic powder consisting of an average of 250 spherical particles
Parts by weight (hereinafter simply referred to as "parts"): Vinyl chloride, vinyl acetate/vinyl alcohol copolymer 12 parts, acrylonitrile/butadiene copolymer 8 parts, cyclohexanone/methyl isobutyl ketone mixed solvent (mixing ratio 1:1) 100 parts
A magnetic paint was prepared by mixing and dispersing the paint components consisting of 100% and 100% in a ball mill for 72 hours, and applied with a gravure coater so that the dry thickness became the specified thickness. Roll pressure during calendering (88 Ky/car) average surface roughness 8o8,
The maximum roughness was controlled to 500.

■　支持体であるフィルム表面ヲＡｒ　Ｏ，Ｉ　Ｔｏｒ
ｒ。■ The surface of the film that is the support is Ar O, I Tor.
r.

５００Ｖ　、Ｉ　Ａ（７）交流グロー放電（周波数６０
１＋／）で２秒間処理し、直径３０Ｃｒｎの２３０℃に
表面温度に保持した誘導加熱式の熱ローラに沿わせて移
動させなからＦｅをターゲットとじて２極スパツタ法に
よりγ−りｅ２０３薄膜を形成した。熱ローラとターゲ
ットの至近距離は６・６ｃｍで放電ガスは、Ａｒか”ｓ
　ｘ　１ｏ　Ｔｏｒ　ｒ　、　Ｈ２ｙ３・”５Ｘ１０　
Ｔｏｒｒ　の混合気体で、放電のタイプは１３・５６Ｍ
Ｈｚの高周波放電で、投入電力は１、ｅＫＷ、反射電力
は０．０３ＫＷ　であった。500V, IA (7) AC glow discharge (frequency 60
1+/) for 2 seconds, and then moved it along an induction-heated heated roller with a diameter of 30 Crn and kept at a surface temperature of 230 °C. Then, a γ-reduced E203 thin film was formed by the bipolar sputtering method using Fe as a target. Formed. The close distance between the heat roller and the target is 6.6 cm, and the discharge gas is Ar or "s".
x 1o Tor r, H2y3・”5X10
Torr gas mixture, discharge type is 13.56M
The input power was 1, eKW, and the reflected power was 0.03KW with a high frequency discharge of Hz.

■　支持体を表面温度５０℃に保持した直径５ｏＣＩｒ
Ｌのローラに沿って移動させて、ローラの真下３０．に
置いた電子ビーム蒸発源よりＦｅを６２０人／ＳｅＣテ
蒸発させ、酸素分圧１．３Ｘ１０’Ｔｏｒｒで反応蒸着
した。■ Diameter 5oCIr with support maintained at a surface temperature of 50℃
Move it along the L roller and place it directly under the roller 30. Fe was evaporated at a rate of 620 people/SeC using an electron beam evaporation source placed in the wafer, and reactive evaporation was performed at an oxygen partial pressure of 1.3×10'Torr.

■　支持体を■と同一の表面処理し、■で用いた装置を
改造してＣｏ−０ｒを電子ビーム蒸着した。即ち、直径
３ｏαの２５０℃に表面温度に保持した誘導加熱式の熱
ローラに沿わせて支持体を移動させ、前記熱ローラの真
下２９ＣＩｒＬに１ｄいた電子ビーム蒸発源よりＣｏ−
Ｃｒを１０６０人／渡で蒸発させ、熱ローラ表面から２
ｃｒｒＬ離れた位置に配置した、２部幅のスリットを通
過する蒸気流で垂直蒸着を行った。(2) The support was subjected to the same surface treatment as (2), and Co-0r was deposited by electron beam by modifying the apparatus used in (2). That is, the support was moved along an induction heating type heat roller having a diameter of 3oα and whose surface temperature was maintained at 250°C, and Co-
Cr is evaporated at 1060 people/wad, and 2
Vertical deposition was performed with vapor flow passing through a double width slit placed crrL apart.

真空度は８Ｘ１０　Ｔｏｒｒ　であった。The degree of vacuum was 8×10 Torr.

■　■で用いた装置で、ターゲ、ントの材料を変えて２
極スパツタによりそれぞれ所定の薄膜を形成した。但し
熱ローラの表面温度は１５０’Ｃで、放電ガスはＡｒ　
ｅ　Ｘ　１０　’Ｔｏｒｒ、　Ｈ２１ｘ１０　Ｔｏｒｒ
　で、１３　、５６　Ｍｌ−１ｚの高周波で投入電力は
１．４ＫＷ、反射電力は０．０２ＫＷであった。■ Using the device used in ■, we changed the target and target materials and
A predetermined thin film was formed using polar sputtering. However, the surface temperature of the heat roller is 150'C, and the discharge gas is Ar.
e X 10' Torr, H21x10 Torr
The input power was 1.4 KW and the reflected power was 0.02 KW at a high frequency of 13,56 Ml-1z.

■　■で用いた装置で酸素分圧５Ｘ１０　Ｔｏｒｒで最
小入射角が４１°になるマスクを用いてＣｏ　−Ｎ　ｉ
を電子ビームで加熱気化させ斜め蒸着した。■ With the equipment used in ■, Co - Ni
was vaporized by heating with an electron beam and deposited obliquely.

上記より明らかなように本発明の磁気記録媒体は、輝度
信号９色信号共に優れたｆ３／Ｎを示し、特に短波長で
ある輝度信号では実用の目安がおよそ４５〜ａ　ｅ　ｄ
Ｂ　といわれていることとあわせ考えても、ずば抜けて
おり、複製する余裕すらあり、録画、録音での高密度記
録に格好の媒体といえる。As is clear from the above, the magnetic recording medium of the present invention exhibits excellent f3/N for both the luminance signal and the nine color signals, and the practical guideline for the luminance signal, which is particularly short wavelength, is approximately 45~a e d
Considering the fact that it is said to be B, it is outstanding, and there is even room for duplication, making it an ideal medium for high-density recording and recording.

発明の効果 本発明の磁気記録媒体は、第１の磁性層を等方向な性質
にして、第２の磁性層を支持体面と垂直な方向に磁化容
易軸を有する強磁性金属薄膜で形成することで、雑音を
下げ、信号出力をあげ、結果的にＳ／Ｎを飛躍的に向上
させたもので、広帯域の信号記録再生に適し、信号の種
類を問わず、高密度記録を可能にする。Effects of the Invention In the magnetic recording medium of the present invention, the first magnetic layer is made isotropic, and the second magnetic layer is formed of a ferromagnetic metal thin film having an axis of easy magnetization in a direction perpendicular to the support surface. This technology reduces noise, increases signal output, and dramatically improves the S/N ratio.It is suitable for wideband signal recording and reproduction, and enables high-density recording regardless of the type of signal.

【図面の簡単な説明】[Brief explanation of drawings]

図は本発明の実施例における磁気記録媒体を示す断面図
である。 １・・・・・・支持体、２・・・・・第１の磁性層、３
・・・・・第２の磁性層。The figure is a sectional view showing a magnetic recording medium in an example of the present invention. 1...Support, 2...First magnetic layer, 3
...Second magnetic layer.

Claims (1)

【特許請求の範囲】[Claims] 支持体上に、その支持体の面内方向に磁化容易軸を有す
ると共にその磁化容易軸が等方向である第１の磁性層と
、その第１の磁性層上に前記支持体面と垂直な方向に磁
化容易軸を有する強磁性金属薄膜から成る第２の磁性層
とを備えたことを特徴とする磁気記録媒体。a first magnetic layer on a support having an easy axis of magnetization in the in-plane direction of the support and whose easy axis of magnetization is equidirectional; and a first magnetic layer on the first magnetic layer in a direction perpendicular to the plane of the support. and a second magnetic layer made of a ferromagnetic metal thin film having an easy axis of magnetization.