JPS5987612A - Vertical magnetic recording system - Google Patents
Vertical magnetic recording systemInfo
- Publication number
- JPS5987612A JPS5987612A JP19815982A JP19815982A JPS5987612A JP S5987612 A JPS5987612 A JP S5987612A JP 19815982 A JP19815982 A JP 19815982A JP 19815982 A JP19815982 A JP 19815982A JP S5987612 A JPS5987612 A JP S5987612A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic recording
- magnetic
- perpendicular magnetic
- core
- ring head
- 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
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
- G11B5/127—Structure or manufacture of heads, e.g. inductive
- G11B5/1278—Structure or manufacture of heads, e.g. inductive specially adapted for magnetisations perpendicular to the surface of the record carrier
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Magnetic Heads (AREA)
Abstract
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、磁気記録媒体の厚み方向の磁化によって記録
する垂直磁気記録方式に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a perpendicular magnetic recording system in which recording is performed by magnetization in the thickness direction of a magnetic recording medium.
背景技術とその問題点
高周波（短波長）信号の記録を行う場合、磁気記録媒体
に磁気ヘッドとの相対的移行方向に沿う方向の磁化忙よ
って記録するいわゆる長手方向磁気記録方式によるより
も、磁気記録媒体の厚さ方向の磁化、いわゆる垂直磁気
記録方式による方が有利であることが知られている。こ
れは長手方向磁気記録方式では記録信号が短波長化なる
ほど自゛己減磁界が大きくなるに比し、垂直磁気記録方
式では磁性層内の自己減磁界が小さくなる性質をもつこ
とに因る。BACKGROUND TECHNOLOGY AND PROBLEMS When recording high frequency (short wavelength) signals, magnetic It is known that magnetization in the thickness direction of the recording medium, so-called perpendicular magnetic recording, is more advantageous. This is because in the longitudinal magnetic recording method, the self-demagnetizing field becomes larger as the recording signal becomes shorter in wavelength, whereas in the perpendicular magnetic recording method, the self-demagnetizing field in the magnetic layer becomes smaller.
この垂直磁気記録方式では磁気記録媒体として、高分子
フィルムなどの非磁性基板上にコバルト・クローム（Ｃ
ｏ −Ｃｒ合金）などの垂直磁気異方性膜を例えばスパ
ッタリングなどで形成した単層膜垂直磁気記録媒体、ま
たは非磁性基板上にノく−マロイなどの高透磁率材層を
形成し、その上にコノ（ルト・クロームなどの垂直磁気
異方性膜を形成した２層膜垂直磁気記録媒体が用いられ
ている。ところで従来、このような単層膜垂直磁気記録
媒体にリングヘッド即ち所要の磁気ギャップを有し閉磁
路を構成するコアからなる磁気ヘッドによって垂直磁気
記録を行う場合、そのリングヘッドのコア材として飽和
磁束密度が４０００ガウス程度のフエライ′トを用いて
いた。このリングヘッドの場合、良好な垂直磁気記録を
行うには、文献によれば垂直磁気異方性膜の垂直異方性
磁界を５ＫＯｅ以上、ヘッドの磁気ギャップ長さ０．５
１１ｍ以下にする必要があった１、しかし、磁気ギャッ
プ長が０．５／Ｂ以下のフェライト製リングヘッドは、
ヘッドのコアの飽和が起き易く、もともとリングヘッド
の記録磁界が回転磁界である為前記の垂直磁気記録媒体
を垂直に飽和記録することが困難であった。従って波長
特性も良好でなく、再生電圧も垂直磁気記録媒体が本来
出し得る値まで取り出すことができないという欠点があ
った。特に垂直磁気記録媒体の異方性磁界が５ＫＯｅ以
下の場合には上記の欠点が顕著になる為、リングヘッド
によって良好な垂直磁気記録を行うことが困難であった
１゜発明の目的
本発明は、上述の点Ｋｇみリングヘッドを用いて良好な
垂直磁気記録が行える垂直磁気記録方式を提供するもの
ではる。In this perpendicular magnetic recording method, the magnetic recording medium is cobalt chromium (C) on a non-magnetic substrate such as a polymer film.
A single-layer perpendicular magnetic recording medium in which a perpendicular magnetic anisotropic film such as O-Cr alloy is formed by sputtering, or a high magnetic permeability material layer such as Noku-Malloy is formed on a non-magnetic substrate. A two-layer perpendicular magnetic recording medium is used, in which a perpendicular magnetic anisotropic film such as chromium chloride is formed on top of the perpendicular magnetic anisotropic film. Conventionally, such a single-layer perpendicular magnetic recording medium has a ring head, that is, a When perpendicular magnetic recording is performed using a magnetic head consisting of a core that has a magnetic gap and forms a closed magnetic path, ferrite with a saturation magnetic flux density of about 4000 Gauss is used as the core material of the ring head. According to the literature, in order to perform good perpendicular magnetic recording, the perpendicular anisotropy field of the perpendicular magnetic anisotropic film should be 5 KOe or more, and the magnetic gap length of the head should be 0.5.
However, a ferrite ring head with a magnetic gap length of 0.5/B or less,
The core of the head is easily saturated, and since the recording magnetic field of the ring head is originally a rotating magnetic field, it has been difficult to perform perpendicular saturation recording on the perpendicular magnetic recording medium. Therefore, the wavelength characteristics are not good, and the reproduction voltage cannot reach the value that the perpendicular magnetic recording medium can originally produce. In particular, when the anisotropic magnetic field of the perpendicular magnetic recording medium is 5 KOe or less, the above-mentioned drawbacks become noticeable, making it difficult to perform good perpendicular magnetic recording with a ring head. The present invention provides a perpendicular magnetic recording system that can perform good perpendicular magnetic recording using the above-mentioned point Kg ring head.
発明の概要
本発明は、垂直磁気異方性膜な有する垂直磁気記録媒体
にリングヘッドで記録する垂直磁気記録方式に於て、コ
アの飽和磁束密度が７０００ガウス以上のリングヘッド
によって垂直磁気記録することを特徴とするものである
。この垂直磁気記録方式によれば、再生電圧、波長特性
ともに大幅に改善され、リングヘッドによる良好な垂直
磁気記録が可能となる。Summary of the Invention The present invention relates to a perpendicular magnetic recording method in which a ring head performs recording on a perpendicular magnetic recording medium having a perpendicular magnetic anisotropic film. It is characterized by this. According to this perpendicular magnetic recording method, both the reproduction voltage and wavelength characteristics are significantly improved, and good perpendicular magnetic recording using a ring head becomes possible.
実施例 以下、本発明の実施例について述べる。Example Examples of the present invention will be described below.
第１図は、高分子フィルムなどの非磁性基板（１）上に
コバルト・クロームなどの垂直磁気異方性膜（２）をス
パッタリングなどで被着形成してなる単層膜垂直磁気記
録媒体＋３１ Ｋ、磁気ギャップｇを有し閉磁路を構成
するコア（４）からなるリングヘッド（５）によって垂
直磁気記録する例である。ｇｇ２図は、高分子フィルム
などの非磁性基板（Ｉ゛）上にパーマロイなどの茜透磁
率材層（６）を形成し、その上にコバルト・クロームな
どの垂直磁気異方性膜（２）を被着形成した２層膜垂直
磁気記録媒体°（７）に、リングヘッドｆ５１ Ｋよっ
て垂直磁気記録する例である。本発明においては、単層
膜垂直磁気記録媒体（３）または２層膜垂直磁気記録媒
体（７）のいずれの場合忙もコア（４）の飽和磁束密度
か７０００ガウス以上のリングヘッド（５）を用いて垂
直磁気記録するものである。Figure 1 shows a single-layer perpendicular magnetic recording medium +31 in which a perpendicular magnetic anisotropic film (2) such as cobalt chromium is deposited on a non-magnetic substrate (1) such as a polymer film by sputtering or the like. This is an example of perpendicular magnetic recording using a ring head (5) consisting of a core (4) having a magnetic gap g and a magnetic gap g. Figure gg2 shows a layer of permalloy or other permeable permeable material (6) formed on a non-magnetic substrate (I) such as a polymer film, and a perpendicular magnetic anisotropic film (2) of cobalt chrome or the like on top of it. This is an example in which perpendicular magnetic recording is performed using a ring head f51K on a two-layer perpendicular magnetic recording medium (7) on which a perpendicular magnetic recording medium is deposited. In the present invention, in either a single-layer perpendicular magnetic recording medium (3) or a double-layer perpendicular magnetic recording medium (7), the ring head (5) has a saturation magnetic flux density of the core (4) of 7000 Gauss or more. It uses perpendicular magnetic recording.
第３図は本発明による垂直磁気記録と従来のリングヘッ
ドを用いた場合の垂直磁気記録とを比較した波長特性図
である。ここでは、垂直異方性磁界ＨＫを異にした２種
の垂直磁気記録媒体Ａ及びＢを使用した。媒体Ａはポリ
イミドの非磁性基板上に、Ｃｏ −Ｃｒ合金（、Ｃｒが
２０原子％含有）による厚さ０．５μｍの垂直磁気異方
性膜をスパッタリングによって被層して得た磁気テープ
で、その磁気特性は飽和磁束密度Ｂｓが５０００ガウス
、抗磁力Ｈｃが１３０００ｅ、垂直異方性磁界ＨＫが４
．２ ＫＯｅである。FIG. 3 is a wavelength characteristic diagram comparing perpendicular magnetic recording according to the present invention with perpendicular magnetic recording using a conventional ring head. Here, two types of perpendicular magnetic recording media A and B with different perpendicular anisotropy magnetic fields HK were used. Medium A is a magnetic tape obtained by sputtering a 0.5 μm thick perpendicular magnetic anisotropic film made of a Co-Cr alloy (containing 20 at% Cr) on a polyimide nonmagnetic substrate. Its magnetic properties include a saturation magnetic flux density Bs of 5000 Gauss, a coercive force Hc of 13000e, and a perpendicular anisotropy magnetic field HK of 4.
．． 2 KOe.
媒体Ｂは上記媒体Ａと同様の構成であって、スパッタリ
ングのＡｒ圧の条件を変えて垂直異方性磁界１−ＩＫを
５．５ＫＯｅとした磁気テープである。Medium B is a magnetic tape having the same structure as medium A, but with different Ar pressure conditions for sputtering and a perpendicular anisotropy magnetic field 1-IK of 5.5 KOe.
第３図中、曲線（ｉ）はコアの飽和磁束密度Ｂｓが１０
０００ガウス、磁気ギャップ長がＱ、３ ｐｍのＦｅ
−ＡＭ−８ｉ系合金（センダスト）からなるリングヘッ
ドで垂直異方性磁界５．５ＫＯｅの垂直磁気記録媒体Ｂ
に記録した場合（本発明）の波長特性である。曲線（…
）は、コアの飽和磁束密度Ｂｓが４０００ガウス゛。In Figure 3, curve (i) indicates that the core saturation magnetic flux density Bs is 10
000 Gauss, magnetic gap length Q, 3 pm Fe
- Perpendicular magnetic recording medium B with a ring head made of AM-8i alloy (Sendust) and a perpendicular anisotropic magnetic field of 5.5 KOe
This is the wavelength characteristic when recorded on (the present invention). curve(…
) has a core saturation magnetic flux density Bs of 4000 Gauss.
磁気ギャップ長が０．３縄のフェライト製リングヘッド
で、垂直異方性磁界５．５ＫＯｅの垂直磁気記録媒体Ｂ
に記録した場合（従来）の波長特性である。Perpendicular magnetic recording medium B with a ferrite ring head with a magnetic gap length of 0.3 rope and a perpendicular anisotropic magnetic field of 5.5 KOe.
This is the wavelength characteristic when recording on (conventional).
曲線（Ｉ）は、同様にコアの飽和磁束密度Ｂｓが４００
０ガウス、磁気ギャップ長か０．３１１ｍの７エライト
製リングヘツドで、垂直異方性磁界４．２ＫＯｅの垂直
磁気記録媒体ＡＫ記録した場合（従来）の波長ｉｔ！ｒ
性である。但し、再生ヘッドは共通であり、コアの飽和
磁束密度Ｂｓが４０００ガウス、磁気ギャップ長が０．
２５１ｆｎのフェライト製リングヘッドである。Similarly, curve (I) shows that the saturation magnetic flux density Bs of the core is 400
When recording on a perpendicular magnetic recording medium AK with a perpendicular anisotropic magnetic field of 4.2 KOe using a 7-elite ring head with a magnetic gap length of 0 Gauss and a magnetic gap length of 0.311 m (conventional), the wavelength it! r
It is gender. However, the read head is the same, with a core saturation magnetic flux density Bs of 4000 Gauss and a magnetic gap length of 0.
251fn ferrite ring head.
曲線（Ｉ）と曲線（川）（１１）とを比較すると、曲線
（１）は曲線（Ｉｔ）（１）よりも再生電圧が４ｄＢ以
上大きく、波長３０ｊＩｍの再生電圧値から６ｄＢ下が
った再生電圧値を示す波長λ５ｏは曲線（Ｉ）の場合、
曲線（ｎ）のλ５ｏの０．８６倍１曲線（１）のλ５ｏ
の０．７３倍である。したがってコアの飽和磁束密度が
１ｏｏｏｏガウスのリングヘッドで記録すれば、コアの
飽和磁束密度が４０００ガウスのリングヘッドで記録す
るよりも、再生電圧、波長特性とも大幅忙改善できる。Comparing curve (I) and curve (river) (11), curve (1) has a reproduction voltage that is 4 dB or more higher than curve (It) (1), and has a reproduction voltage that is 6 dB lower than the reproduction voltage value at wavelength 30jIm. In the case of curve (I), the wavelength λ5o indicating the value is
0.86 times λ5o of curve (n) 1 λ5o of curve (1)
0.73 times. Therefore, by recording with a ring head whose core has a saturation magnetic flux density of 1000 Gauss, both the reproduction voltage and wavelength characteristics can be significantly improved compared to recording with a ring head whose core has a saturation magnetic flux density of 4000 Gauss.
しかも、曲線（１）と（１）の比較で解かる様に、垂直
磁気記録媒体の垂直異方性磁界が５ＫＯｅ以下になると
、コアの飽和磁束密度が４０００ガウスのリングヘッド
で記録した場合には波長特性が短波長側で劣下する忙も
かかわらず、コアの飽和磁束密度が１００００ガウスの
リングヘッドで記録した本発明の場合には垂直磁気記録
媒体の垂直異方性磁界が５ ＫＯｅ以下でも極めて良好
な垂直磁気記録を実現することができる。Furthermore, as can be seen from the comparison of curves (1) and (1), when the perpendicular anisotropy field of the perpendicular magnetic recording medium becomes 5 KOe or less, recording is performed using a ring head with a core saturation magnetic flux density of 4000 Gauss. Although the wavelength characteristics deteriorate on the short wavelength side, in the case of the present invention in which recording is performed using a ring head with a core saturation magnetic flux density of 10,000 Gauss, the perpendicular anisotropy magnetic field of the perpendicular magnetic recording medium is 5 KOe or less. However, extremely good perpendicular magnetic recording can be achieved.
曲線（ＩＶ）はコアの飽和磁束密度が８０００ガウス、
磁気ギャップ長が０．２１ＩｍのＣｏ−Ｆｅ系のアルモ
ファス合金製のリングヘッドで、垂直異方性磁界４．２
ＫＯｅの垂直磁気記録媒体Ａ忙記録した場合（本発明）
の波長特性である。この場合も、曲線（１）とほぼ同等
の効果が得られる。Curve (IV) indicates that the saturation magnetic flux density of the core is 8000 Gauss,
A ring head made of Co-Fe-based amorphous alloy with a magnetic gap length of 0.21 Im and a perpendicular anisotropic magnetic field of 4.2 Im.
KOe perpendicular magnetic recording medium A busy recording case (present invention)
This is the wavelength characteristic of In this case as well, substantially the same effect as curve (1) can be obtained.
尚、垂直磁気記録媒体において、２層膜構造にする場合
はそのコバルト・クロームの垂直磁気異方性膜として異
方性磁界ＨＫの大きいものを作りＫ（いが５本発明の場
合忙はこのような異方性磁界ＨＫの小さい２層膜垂直磁
気記録媒体でも充分に垂直磁気記録ができる。In addition, in the case of a two-layer film structure in a perpendicular magnetic recording medium, a perpendicular magnetic anisotropic film of cobalt chromium with a large anisotropic magnetic field HK is used. Perpendicular magnetic recording can be performed satisfactorily even with such a two-layer perpendicular magnetic recording medium with a small anisotropic magnetic field HK.
発明の効果
上述の本発明によれば、コアの飽和磁束密度Ｂｓが７０
００ガウス以上のリングヘッドト°を用いることＫより
、再生電圧、波長特性ともに大幅に改善され、リングヘ
ッドによる良好な垂直磁気記録が可能となる。また本発
明は従来不可能であった垂直異方性磁界ＨＫが５ ＫＯ
ｅ以下の垂直磁気記録媒体に対してもリングヘッドによ
って良好に垂直磁気記録することを可能にするものであ
る。この為に記録、再生感度の良いリングヘッドを用い
た垂直磁気記録が可能になり、さらに垂直磁気記録媒体
の作製条件が緩和され垂直磁気記録媒体の生産性が大幅
に向上する。Effects of the Invention According to the present invention described above, the saturation magnetic flux density Bs of the core is 70
By using a ring head temperature of 0.00 Gauss or more, both the reproducing voltage and wavelength characteristics are significantly improved, and good perpendicular magnetic recording using the ring head becomes possible. In addition, the present invention has a vertical anisotropy magnetic field HK of 5 KO, which was previously impossible.
This makes it possible to perform perpendicular magnetic recording favorably with a ring head even on perpendicular magnetic recording media of e or less. For this reason, perpendicular magnetic recording using a ring head with good recording and reproducing sensitivity becomes possible, and the manufacturing conditions for perpendicular magnetic recording media are relaxed, which greatly improves the productivity of perpendicular magnetic recording media.
第１図及び第２図は夫々本発明の垂直磁気記録方式の例
を示す断面図、第３図は本発明の垂直磁気記録と従来の
リングヘッドを用いた場合の垂直磁気記録を比較して示
した波長特性図である。
（１１は非磁性基板、ｔ２）は垂直磁気異方性膜、（５
）はリングヘッド、（６）は高透磁率材層である。
波長ｔμ筬フ
手続補正書
（特許庁審判長 殿）１、事件の
表示
昭和５７年特許願第 １９８１５９号
２、 発明（７） 名称 垂直磁気記録方式３、補
正をする者
事件との関係 特許出願人
住所 東京部品用区北品用６ｊ゛目７番３５号名称（２
１８） ソニー株式会社
代表取締役 大 賀 典雄
１゜
１
６、補正により増加する発明の数
７、補正の対 象 明細書の発明の詳細な説明の楠８
、補正の内容
（１）明細書中、第３頁１５行「はる。」を「ある。」
と訂正する。
（２）同、第５頁１８行「５．５ ＫＯｅ （１） 垂
直磁気記録媒体Ｂ」を１４．２ＫＯｅの垂直磁気記録媒
体Ａ」と訂正する。
（３１同、第７頁１１行「アルモフ」を「アモル７」と
訂正する。
以上FIGS. 1 and 2 are cross-sectional views showing examples of the perpendicular magnetic recording method of the present invention, and FIG. 3 is a comparison of perpendicular magnetic recording of the present invention and perpendicular magnetic recording using a conventional ring head. It is a wavelength characteristic diagram shown. (11 is a non-magnetic substrate, t2) is a perpendicular magnetic anisotropic film, (5
) is a ring head, and (6) is a high magnetic permeability material layer. Wavelength tμ Reed Procedural Amendment (Mr. Chief Adjudicator of the Japan Patent Office) 1, Indication of the Case Patent Application No. 198159 of 1981 2, Invention (7) Name Perpendicular Magnetic Recording System 3, Relationship with the Amendment Person Case Patent Application Address Tokyo Parts Ward Kitashina 6j゛ 7-35 Name (2
18) Sony Corporation Representative Director Norio Ohga 1゜1 6. Number of inventions increased by amendment 7. Subject of amendment Kusunoki 8. Detailed explanation of the invention in the specification
, Contents of amendment (1) In the specification, on page 3, line 15, "haru." is replaced with "aru."
I am corrected. (2) Same, page 5, line 18, ``5.5 KOe (1) Perpendicular magnetic recording medium B'' is corrected to ``14.2 KOe perpendicular magnetic recording medium A''. (31, page 7, line 11, “Arumov” is corrected to “Amol 7”.)
Claims (1)
路を構成するコアよりなるリングヘッドで記録する記録
方式忙おいて、上記コアは飽和磁束密度が７０００ガウ
ス以上の材料より成ることを特徴とする垂直磁気記録方
式。In a recording method that records on a perpendicular magnetic anisotropic film with a ring head consisting of a core having a required magnetic gap and forming a closed magnetic path, the core must be made of a material with a saturation magnetic flux density of 7000 Gauss or more. A perpendicular magnetic recording system characterized by
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57198159A JPH0619809B2 (en) | 1982-11-11 | 1982-11-11 | Perpendicular magnetic recording method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57198159A JPH0619809B2 (en) | 1982-11-11 | 1982-11-11 | Perpendicular magnetic recording method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5987612A true JPS5987612A (en) | 1984-05-21 |
| JPH0619809B2 JPH0619809B2 (en) | 1994-03-16 |
Family
ID=16386441
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57198159A Expired - Lifetime JPH0619809B2 (en) | 1982-11-11 | 1982-11-11 | Perpendicular magnetic recording method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0619809B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62126174U (en) * | 1986-01-31 | 1987-08-11 | ||
| US4745510A (en) * | 1985-03-07 | 1988-05-17 | Victor Company Of Japan, Ltd. | Perpendicular magnetic recording and reproducing system |
| EP0490669A2 (en) * | 1990-12-12 | 1992-06-17 | Kabushiki Kaisha Toshiba | A magnetic recording system |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57127908A (en) * | 1981-01-29 | 1982-08-09 | Fuji Photo Film Co Ltd | Magnetic head |
-
1982
- 1982-11-11 JP JP57198159A patent/JPH0619809B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57127908A (en) * | 1981-01-29 | 1982-08-09 | Fuji Photo Film Co Ltd | Magnetic head |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4745510A (en) * | 1985-03-07 | 1988-05-17 | Victor Company Of Japan, Ltd. | Perpendicular magnetic recording and reproducing system |
| JPS62126174U (en) * | 1986-01-31 | 1987-08-11 | ||
| EP0490669A2 (en) * | 1990-12-12 | 1992-06-17 | Kabushiki Kaisha Toshiba | A magnetic recording system |
| US5396391A (en) * | 1990-12-12 | 1995-03-07 | Kabushiki Kaisha Toshiba | Magnetic recording system providing a magnetic head having opposite sides for applying different magnetic field strengths to a magnetic recording medium |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0619809B2 (en) | 1994-03-16 |
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