JPS62159330A - Magnetic recording medium - Google Patents

Magnetic recording medium

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Publication number
JPS62159330A
JPS62159330A JP88886A JP88886A JPS62159330A JP S62159330 A JPS62159330 A JP S62159330A JP 88886 A JP88886 A JP 88886A JP 88886 A JP88886 A JP 88886A JP S62159330 A JPS62159330 A JP S62159330A
Authority
JP
Japan
Prior art keywords
silica
magnetic recording
recording medium
layer
contg
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
Application number
JP88886A
Other languages
Japanese (ja)
Other versions
JPH0731806B2 (en
Inventor
Sanemori Soga
眞守 曽我
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP61000888A priority Critical patent/JPH0731806B2/en
Publication of JPS62159330A publication Critical patent/JPS62159330A/en
Publication of JPH0731806B2 publication Critical patent/JPH0731806B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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  • Magnetic Record Carriers (AREA)

Abstract

PURPOSE:To improve slipperiness and durability and to maintain the same for a long period of time by forming a silicon compd.-contg. layer on a thin ferromagnetic film provided on a nonmagnetic substrate and forming a higher aliphat. amine-contg. layer thereon. CONSTITUTION:This recording medium is formed by forming the silicon compd.- contg. layer 3 on the thin ferromagnetic film 2 and providing the higher aliphat. amine-contg. layer 4 thereon. the silicon compd. which can be used is silica.alumina or silica.nickel oxide. The ratio of the silica in the silica, alumina or silica.nickel oxide is preferably 40-90% silica in molar ratio and the compd. having such ratio adsorbs the higher aliphat. amine strongly. The film thickness of the silicon compd.-contg. layer 3 is adequately 5-40nm. Output is decreased by a spacing loss in the stage of reproducing signals if the film thickness is larger than 50nm and there is an easy tendency to pinholing if the film thickness is smaller than 5nm.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、情報産業分野等で利用される高記録密度の磁
気記録媒体に関する。
DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a high recording density magnetic recording medium used in the information industry and the like.

従来の技術 従来の塗布型磁気記録媒体に代わって、メッキ、法、ス
パッタリング法、真空蒸着法、イオンブレーティング法
等の方法によって、強磁性金属薄膜を非磁性基板上に設
けた磁気記録媒体は、高記録密度用磁気記録媒体として
研究されている。
Conventional technology In place of conventional coating-type magnetic recording media, magnetic recording media in which a ferromagnetic metal thin film is provided on a non-magnetic substrate by methods such as plating, sputtering, vacuum evaporation, and ion blating are available. , is being researched as a magnetic recording medium for high recording density.

しかしながら、上述した方法で作られる強磁性金属薄膜
を用いた磁気記録媒体は、その耐摩耗性及び走行性に問
題がある。
However, the magnetic recording medium using the ferromagnetic metal thin film produced by the method described above has problems in its wear resistance and running properties.

磁気記録媒体は磁気信号の記録、再生の過程において、
磁気ヘッドとの高速相対運動におかれる。
In the process of recording and reproducing magnetic signals, magnetic recording media
It is placed in high-speed relative motion with the magnetic head.

この時、磁気記録媒体の走行が円滑でかつ安定で行なわ
れなければならない。また磁気ヘッドとの接触による摩
耗や破損が起きてはならない。
At this time, the magnetic recording medium must run smoothly and stably. Furthermore, wear and damage due to contact with the magnetic head must not occur.

しかしながら、上述したごとき方法で作られた強磁性金
属薄膜は磁気記録、再生の過程の苛酷な条件に耐えるこ
とができず、磁気ヘッド等の摩擦によって走行が不安定
になったり、長時間走行させた場合には摩耗したり、破
損したり、摩耗粉の発生によって著しく出力が低下する
ことがあった。
However, the ferromagnetic metal thin film made by the method described above cannot withstand the harsh conditions of the magnetic recording and reproducing process, and the running becomes unstable due to the friction of the magnetic head, etc., and the ferromagnetic metal thin film made by the method described above cannot withstand the harsh conditions of the magnetic recording and reproducing process. In such cases, the output may be significantly reduced due to wear, damage, and generation of wear debris.

七のため、強磁性金属薄膜上に保護膜としてモノ直鎖飽
和アルキルアミンからなる膜を形成することが提案され
ている(特開昭597119538号公報)。
Therefore, it has been proposed to form a film made of a monolinear saturated alkylamine as a protective film on a ferromagnetic metal thin film (Japanese Patent Application Laid-Open No. 597119538).

発明が解決しようとする問題点 しかしながら、この場合初期の潤滑性は若干改善が見ら
れるが、滑性耐久性がない。これは、モノ直鎖飽和アル
キルアミンと磁性膜との結合が物理吸着程度の弱いもの
であるため、走行中にしゆう動する磁気ヘッド等により
、モノ直鎖飽和アルキルアミンが削り取られるからであ
る。
Problems to be Solved by the Invention However, in this case, although the initial lubricity is slightly improved, the durability of the lubricity is lacking. This is because the bond between the monolinear saturated alkylamine and the magnetic film is weak, at the level of physical adsorption, and the monolinear saturated alkylamine is scraped off by a magnetic head or the like that moves while the vehicle is running.

本発明はかかる点に鑑みてなされたもので、滑性耐久性
のすぐれた磁気記録媒体を提供することを目的としてい
る。
The present invention has been made in view of these points, and an object of the present invention is to provide a magnetic recording medium with excellent slipperiness and durability.

問題点を解決するための手段 非磁性基板上に設けた強磁性金属薄膜上に、シリコン化
合物含有層を形成し、その上に高級脂肪族アミン含有層
を形成する。
Means for Solving the Problems A silicon compound-containing layer is formed on a ferromagnetic metal thin film provided on a non-magnetic substrate, and a higher aliphatic amine-containing layer is formed thereon.

作用 シリカ・アルミナもしくはシリカ・酸化ニッケル等のシ
リコン化合物は酸性の強い化合物である。
Function Silicon compounds such as silica/alumina or silica/nickel oxide are strongly acidic compounds.

そのため塩基性化合物である高級脂肪族アミンは前記シ
リコン化合物に強く化学吸着する。その結果、シリコン
化合物含有層を形成し、その上に高級脂肪族アミン含有
層を形成した磁気記録媒体では、磁気ヘッド等で摩擦し
ても潤滑剤である高級脂肪族アミンが磁性表面から削り
取られることがないので、滑性耐久性のすぐれた磁気記
録媒体が得られる。
Therefore, higher aliphatic amines, which are basic compounds, are strongly chemically adsorbed onto the silicon compound. As a result, in magnetic recording media in which a silicon compound-containing layer is formed and a higher aliphatic amine-containing layer is formed on top of the layer, the higher aliphatic amine, which is a lubricant, is scraped off from the magnetic surface even when rubbed by a magnetic head, etc. Therefore, a magnetic recording medium with excellent slipperiness and durability can be obtained.

実施例 図は本発明の磁気記録媒体の断面図である。図において
、1は非磁性基板、2は強磁性金属薄膜、3はシリコン
化合物含有層、4は高級脂肪族アミン含有層である。
The embodiment diagram is a cross-sectional view of the magnetic recording medium of the present invention. In the figure, 1 is a nonmagnetic substrate, 2 is a ferromagnetic metal thin film, 3 is a silicon compound-containing layer, and 4 is a higher aliphatic amine-containing layer.

本発明による磁気記録媒体に使用しうる非磁性基板1と
しては、ポリ塩化ビニル、酢酸セルロース、ポリエチレ
ンテレフタレート、ポリエチレン。
Examples of the nonmagnetic substrate 1 that can be used in the magnetic recording medium according to the present invention include polyvinyl chloride, cellulose acetate, polyethylene terephthalate, and polyethylene.

ポリプロピレン、ポリカーボネート、ポリイミド、ポリ
アミド等の高分子材料、非磁性金属材料、ガラス、磁器
等のセラミック材料等周知の材料からなるフィルム、板
等がある。
There are films, plates, etc. made of well-known materials such as polymeric materials such as polypropylene, polycarbonate, polyimide, and polyamide, nonmagnetic metal materials, and ceramic materials such as glass and porcelain.

また1本発明の磁気記録媒体に使用しうる強磁性金属薄
膜2を形成しうる強磁性材料としては、周知の任意の材
料を使用でき、例えば鉄、コバルト、ニッケルの1種以
上の合金またはこれらと、他の金属例えばマンガン、ク
ロム、チタン、リンイツトリウム、サマリウム、ビスマ
ス等とを組合わせた合金があり、また上記金属の酸化物
等がある。
Further, as the ferromagnetic material that can form the ferromagnetic metal thin film 2 that can be used in the magnetic recording medium of the present invention, any known material can be used, such as an alloy of one or more of iron, cobalt, and nickel, or an alloy of these. There are alloys made by combining metals with other metals such as manganese, chromium, titanium, phosphorous, samarium, bismuth, etc., and oxides of the above metals.

非磁性基板1上に強磁性金属薄膜2を形成させるに当た
っては真空蒸着法、スパッタリング法、イオンブレーテ
ィング法、メッキ法等任意の周知の方法で形成させるこ
とができる。
The ferromagnetic metal thin film 2 can be formed on the nonmagnetic substrate 1 by any known method such as vacuum evaporation, sputtering, ion blasting, or plating.

本発明においては、上述したごとき強磁性金属薄膜2の
上にシリコン化合物含有層3を形成し、その上に高級脂
肪族アミン含有層4を≠#≠*#設けることが要点であ
る。
In the present invention, the key point is to form the silicon compound-containing layer 3 on the ferromagnetic metal thin film 2 as described above, and to provide the higher aliphatic amine-containing layer 4 thereon.

本発明で使用しつるシリコン化合物はノリ力・アルミナ
もしくはシリカ・酸化ニッケルである。
The vine silicon compound used in the present invention is Noriyoku/alumina or silica/nickel oxide.

シリカ・アルミナ及びシリカ・酸化ニッケルにおけるシ
リカの割合は、モル比でシリカが40%〜90%のもの
がよく、この割合のものが高級脂肪族アミンを強く吸着
させた。
The proportion of silica in silica/alumina and silica/nickel oxide is preferably 40% to 90% by molar ratio, and higher aliphatic amines are strongly adsorbed at this proportion.

シリカ・アルミナはシリカゲルとアルミナゲルとを湿っ
た状態で練り合わせる方法、シリカゲルにアルミニウム
塩を浸漬法で付ける方法、シリカとアルミナとを水溶液
から同時にゲル化させる方法、シリカゲル上にアルミナ
ゲルを沈着させる方法、シリカ粉末とアルミナ粉末と混
ぜ合わせて圧縮し、固める方法のいずれかによってつく
られる。
Silica and alumina can be produced by mixing silica gel and alumina gel in a wet state, applying aluminum salt to silica gel by dipping, gelling silica and alumina simultaneously from an aqueous solution, and depositing alumina gel on silica gel. It is made by mixing silica powder and alumina powder, compressing it, and solidifying it.

シリカ・酸化ニッケルもシリカ・アルミナと同じような
方法でつくられる。
Silica and nickel oxide are also produced in the same way as silica and alumina.

本発明により強磁性金属薄膜2上に、シリコン化合物含
有層3を形成するに当たっては、スパッタリング法で形
成させることができる。
According to the present invention, the silicon compound-containing layer 3 can be formed on the ferromagnetic metal thin film 2 by a sputtering method.

本発明により強磁性金属薄膜2上に、シリコン化合物含
有層3を形成する場合、その膜厚は5〜40 n mが
好適である。
When forming the silicon compound-containing layer 3 on the ferromagnetic metal thin film 2 according to the present invention, the film thickness is preferably 5 to 40 nm.

上記膜厚が5onmより犬となると、信号の再生時にス
ペーシングロスにより出力が低下した。
When the film thickness was greater than 5 onm, the output decreased due to spacing loss during signal reproduction.

またsnmよシ小さくなると、ピンホールが生じやすく
なって、高級脂肪族アミンとの複合効果が期待できなか
った。
Furthermore, as the SNM becomes smaller, pinholes tend to occur, and a combined effect with higher aliphatic amines cannot be expected.

本発明によれば、上述したシリコン化合物含有層3の上
に、高級脂肪族アミン含有層4を設ける。
According to the present invention, the higher aliphatic amine-containing layer 4 is provided on the silicon compound-containing layer 3 described above.

本発明で使用しうる高級脂肪族アミンは炭素数12〜2
6の炭化水素鎖を含有する化合物である。
The higher aliphatic amine that can be used in the present invention has 12 to 2 carbon atoms.
It is a compound containing 6 hydrocarbon chains.

炭素数が11以下の場合、十分な潤滑性が得られない。When the number of carbon atoms is 11 or less, sufficient lubricity cannot be obtained.

1だ、炭素数27以上の炭化水素鎖を持つ脂肪族アミン
では、それ以上の潤滑性の向上は見られず耐久性が低下
してしまう。
1. Aliphatic amines with a hydrocarbon chain of 27 or more carbon atoms do not improve lubricity any further and their durability deteriorates.

本発明で使用しうる高級脂肪族アミンとして、ラウリル
アミン、テトラデシルアミン、ヘキサデシルアミン、ス
テアリルアミン、イコシルアミン、トコジルアミン、テ
トラデシルアミン、ヘキサコ/ルアミン等がある。
Higher aliphatic amines that can be used in the present invention include laurylamine, tetradecylamine, hexadecylamine, stearylamine, icosylamine, tocodylamine, tetradecylamine, hexaco/luamine, and the like.

/リコン化合物含有層3の上に高級脂肪族アミン含有層
4を形成するに当たっては、真空蒸着法、コーティング
法、ラングミュア・プロジェット法等の方法で形成させ
ることができる。
The higher aliphatic amine-containing layer 4 can be formed on the silicon compound-containing layer 3 by a vacuum deposition method, a coating method, a Langmuir-Prodgett method, or the like.

本発明によシリコン化合物含有層3の上に高級脂肪族ア
ミン含有層4を形成する場合、その膜厚は5〜45 n
 mが好適であり、10〜3onmが好ましい。ただし
、シリコン化合物含有層3と合わせた厚さを50nm以
下にする必要がある。
When the higher aliphatic amine-containing layer 4 is formed on the silicon compound-containing layer 3 according to the present invention, the film thickness is 5 to 45 nm.
m is suitable, and 10 to 3 onm is preferable. However, the combined thickness of the silicon compound-containing layer 3 needs to be 50 nm or less.

5Gnmより犬になると、信号の再生時にスペーシング
ロスにより出力が低下するので好ましくない。また、高
級脂肪族アミン含有層4の膜厚が5nmより小さくなる
と潤滑性が著しく低下するので好ましくない。
If the wavelength is smaller than 5 Gnm, the output will decrease due to spacing loss during signal reproduction, which is not preferable. Furthermore, if the thickness of the higher aliphatic amine-containing layer 4 is less than 5 nm, the lubricity will be significantly reduced, which is not preferable.

以下に具体的な例を挙げて本発明を説明する。The present invention will be explained below by giving specific examples.

〔実施例〕〔Example〕

厚さ20μmのポリイミドフィルム基板上に、真空蒸着
法によりコバル)(90%)−クロム(10%)からな
る膜厚150nmの強磁性金属薄膜を作った。この強磁
性金属薄膜を形成した基板から直径76rIrmの大き
さの片を切りとり、上記強磁性金属薄膜の上に、アルゴ
ンガスを導入して高周波スパッタ法により膜厚10nm
のシリコン化合物含有層を形成した。アルゴンガス圧は
2×1o  Torr  とし、ターゲットには下記の
組成を持つ各7リコン化合物を用いた。
A 150 nm thick ferromagnetic metal thin film made of cobal (90%)-chromium (10%) was formed on a 20 μm thick polyimide film substrate by vacuum evaporation. A piece with a diameter of 76 rIrm was cut from the substrate on which this ferromagnetic metal thin film was formed, and argon gas was introduced onto the ferromagnetic metal thin film to form a film with a thickness of 10 nm by high-frequency sputtering.
A silicon compound-containing layer was formed. The argon gas pressure was 2×10 Torr, and seven recon compounds having the following compositions were used as targets.

試料1〜37リカ・アルミナ (5i02 : k1203:1 : 1モル比) 試料4〜6 シリカ・酸化ニッケル (5in2: Ni0= 2 : 1モル比)次にスピ
ナーを用いて、下記の1100pp高級脂肪族アミンの
イングロパノール溶液を前記シリコン化合物層の上にコ
ーティングした。
Samples 1 to 37 silica/alumina (5i02:k1203:1:1 molar ratio) Samples 4 to 6 silica/nickel oxide (5in2:Ni0=2:1 molar ratio) Next, using a spinner, the following 1100pp higher aliphatic A solution of amine in ingropanol was coated onto the silicon compound layer.

試料1と4ニラウリルアミン 試料2と5:ステアリルアミン 試料3と6:へキサコンルアミン 2cc の前記アミン溶液を50Orpmの回転で塗工
し、引き続いて、回転数を11000rl)に上げて、
溶媒を乾燥させた。試料を真空乾燥後、シリコン化合物
層上に形成された高級脂肪族アミン層をエリプソメータ
で測定したところ膜厚は15nmであった。
Samples 1 and 4 Nilaurylamine Samples 2 and 5: Stearylamine Samples 3 and 6: Hexaconylamine 2 cc of the amine solution was applied at a rotation speed of 50 Orpm, and subsequently the rotation speed was increased to 11000 rl).
The solvent was dried. After vacuum drying the sample, the higher aliphatic amine layer formed on the silicon compound layer was measured with an ellipsometer and found to have a film thickness of 15 nm.

〔比較例〕[Comparative example]

前記実施例において、強磁性金属薄膜の上尾シリコン化
合物層を形成せずに、直接高級脂肪族アミンを同じ条件
でスピンコードシタ。
In the above embodiments, higher aliphatic amines were directly spin-coded under the same conditions without forming a silicon compound layer on top of the ferromagnetic metal thin film.

試料7:ラウリルアミン 試料8:ステアリルアミン 試料s:ヘキサコシルアミン 実施例の試料1〜6、および比較例の試料7〜9の動摩
擦係数を動摩擦係数針(DFPM型、協和科学層)で測
定した。ヘッドは直径12咽のSUJ鋼球で、ヘッド荷
重1ooy、ヘッドの走行速度1 、Orran / 
sで測定した。その結果を下記に示す。
Sample 7: Laurylamine Sample 8: Stearylamine Sample s: Hexacosylamine The dynamic friction coefficients of Examples 1 to 6 and Comparative Examples 7 to 9 were measured with a dynamic friction coefficient needle (DFPM type, Kyowa Kagaku Seiya). . The head is a SUJ steel ball with a diameter of 12 mm, head load 1ooy, head running speed 1, Orran /
Measured at s. The results are shown below.

(以下余白) 表のデータから本発明による実施例(試料1〜6)の磁
気記録媒体は初期動摩擦係数は勿論、200回往復後に
おいても動摩擦係数が低く、滑性耐久性において、比較
例(試料7〜9)より優れていることがわかる。
(Margins below) From the data in the table, it is clear that the magnetic recording media of Examples (Samples 1 to 6) according to the present invention have a low coefficient of dynamic friction not only at the initial stage but also after 200 reciprocations, and in terms of lubricity durability, compared to the comparative example (Samples 1 to 6). It can be seen that this sample is superior to samples 7 to 9).

またこれらの磁気記録媒体を市販のフロッピーディスク
と同等の機能を有する試験機で走行させたところ、実施
例の磁気記録媒体はいずれも、100時間後も走行が安
定し、摩耗傷は見られなかった。それに対し比較例の磁
気記録媒体は走行が不安定になり、磁性面に摩耗傷が見
られた。
Furthermore, when these magnetic recording media were run on a test machine with the same functionality as a commercially available floppy disk, all of the magnetic recording media of the examples ran stably even after 100 hours, and no wear scratches were observed. Ta. On the other hand, the magnetic recording medium of the comparative example ran unstable, and wear scratches were observed on the magnetic surface.

なお以上の実施例では磁気ディスクについて示したが、
本発明の磁気記録媒体は、磁気テープ、磁気カード等に
も適用できることは明らかである。
Note that although the above embodiments have been described with respect to magnetic disks,
It is clear that the magnetic recording medium of the present invention can also be applied to magnetic tapes, magnetic cards, etc.

発明の効果 本発明の磁気記録媒体は滑性耐久性にすぐれ、それを長
期間維持することができる。
Effects of the Invention The magnetic recording medium of the present invention has excellent slipperiness and durability and can maintain it for a long period of time.

【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の断面図であ
る。 1・・・・・・非磁性基板、2・・・・・・強磁性金属
薄膜、3・・・・・・シリコン化合物含有層、4・・・
・・・高級脂肪族アミン含有層。 代理人の氏名 弁理士 中 尾 敏 男 ほか1名高8
(脂月方オ矢アミン合有屡
The figure is a sectional view of a magnetic recording medium in an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Nonmagnetic substrate, 2...Ferromagnetic metal thin film, 3...Silicon compound containing layer, 4...
...Higher aliphatic amine-containing layer. Name of agent: Patent attorney Toshio Nakao and 1 other high school student
(Katsuzuki Kata Oya Amin Goyuta

Claims (4)

【特許請求の範囲】[Claims] (1)非磁性基板上に設けた強磁性金属薄膜上に、シリ
コン化合物含有層を形成し、その上に高級脂肪族アミン
含有層を設けた磁気記録媒体。
(1) A magnetic recording medium in which a silicon compound-containing layer is formed on a ferromagnetic metal thin film provided on a non-magnetic substrate, and a higher aliphatic amine-containing layer is provided thereon.
(2)シリコン化合物がシリカ・アルミナもしくはシリ
カ・酸化ニッケルである特許請求の範囲第1項記載の磁
気記録媒体。
(2) The magnetic recording medium according to claim 1, wherein the silicon compound is silica/alumina or silica/nickel oxide.
(3)シリコン化合物含有層の厚さが5〜40nmであ
る特許請求の範囲第1項記載の磁気記録媒体。
(3) The magnetic recording medium according to claim 1, wherein the silicon compound-containing layer has a thickness of 5 to 40 nm.
(4)高級脂肪族アミンが炭素数12〜26の炭化水素
鎖を含有する特許請求の範囲第1項記載の磁気記録媒体
(4) The magnetic recording medium according to claim 1, wherein the higher aliphatic amine contains a hydrocarbon chain having 12 to 26 carbon atoms.
JP61000888A 1986-01-07 1986-01-07 Magnetic recording medium Expired - Fee Related JPH0731806B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP61000888A JPH0731806B2 (en) 1986-01-07 1986-01-07 Magnetic recording medium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP61000888A JPH0731806B2 (en) 1986-01-07 1986-01-07 Magnetic recording medium

Publications (2)

Publication Number Publication Date
JPS62159330A true JPS62159330A (en) 1987-07-15
JPH0731806B2 JPH0731806B2 (en) 1995-04-10

Family

ID=11486214

Family Applications (1)

Application Number Title Priority Date Filing Date
JP61000888A Expired - Fee Related JPH0731806B2 (en) 1986-01-07 1986-01-07 Magnetic recording medium

Country Status (1)

Country Link
JP (1) JPH0731806B2 (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6038729A (en) * 1983-08-09 1985-02-28 Nec Corp Magnetic storage body
JPS60211613A (en) * 1984-04-04 1985-10-24 Hitachi Maxell Ltd Magnetic recording medium

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6038729A (en) * 1983-08-09 1985-02-28 Nec Corp Magnetic storage body
JPS60211613A (en) * 1984-04-04 1985-10-24 Hitachi Maxell Ltd Magnetic recording medium

Also Published As

Publication number Publication date
JPH0731806B2 (en) 1995-04-10

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