JPH03224119A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPH03224119A JPH03224119A JP1860490A JP1860490A JPH03224119A JP H03224119 A JPH03224119 A JP H03224119A JP 1860490 A JP1860490 A JP 1860490A JP 1860490 A JP1860490 A JP 1860490A JP H03224119 A JPH03224119 A JP H03224119A
- Authority
- JP
- Japan
- Prior art keywords
- thin film
- magnetic recording
- metal thin
- recording medium
- ferromagnetic metal
- 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.)
- Pending
Links
- 230000005291 magnetic effect Effects 0.000 title claims abstract description 70
- 239000010409 thin film Substances 0.000 claims abstract description 67
- 229910052751 metal Inorganic materials 0.000 claims abstract description 44
- 239000002184 metal Substances 0.000 claims abstract description 44
- 230000005294 ferromagnetic effect Effects 0.000 claims abstract description 32
- 239000000758 substrate Substances 0.000 claims abstract description 20
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims abstract description 19
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims abstract description 19
- 239000010408 film Substances 0.000 abstract description 14
- 230000005415 magnetization Effects 0.000 abstract description 8
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 5
- 239000001301 oxygen Substances 0.000 abstract description 5
- 229910052760 oxygen Inorganic materials 0.000 abstract description 5
- 238000000034 method Methods 0.000 abstract description 4
- 238000007740 vapor deposition Methods 0.000 abstract description 4
- 229920000728 polyester Polymers 0.000 abstract description 3
- 230000000052 comparative effect Effects 0.000 description 15
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 10
- 239000010936 titanium Substances 0.000 description 10
- 229910052719 titanium Inorganic materials 0.000 description 10
- 238000005260 corrosion Methods 0.000 description 9
- 230000007797 corrosion Effects 0.000 description 9
- 229910045601 alloy Inorganic materials 0.000 description 6
- 239000000956 alloy Substances 0.000 description 6
- 230000001681 protective effect Effects 0.000 description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- VNNRSPGTAMTISX-UHFFFAOYSA-N chromium nickel Chemical compound [Cr].[Ni] VNNRSPGTAMTISX-UHFFFAOYSA-N 0.000 description 3
- 229910001120 nichrome Inorganic materials 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 238000004544 sputter deposition Methods 0.000 description 2
- 229910002441 CoNi Inorganic materials 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910000599 Cr alloy Inorganic materials 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 239000004642 Polyimide Substances 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000005764 inhibitory process Effects 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000006247 magnetic powder Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 229920000379 polypropylene carbonate Polymers 0.000 description 1
- 229910052594 sapphire Inorganic materials 0.000 description 1
- 239000010980 sapphire Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000007738 vacuum evaporation Methods 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、強磁性金属薄膜を磁気記録層とする磁気記録
媒体に関し、特にこの種の磁気記録媒体の磁気記録層で
ある強磁性金属薄膜に対する耐食性の改良技術に関する
。Detailed Description of the Invention (Industrial Application Field) The present invention relates to a magnetic recording medium having a ferromagnetic metal thin film as a magnetic recording layer, and particularly relates to a ferromagnetic metal thin film which is a magnetic recording layer of this type of magnetic recording medium. This invention relates to technology for improving corrosion resistance.
（従来の技術）
強磁性金属薄膜を磁気記録層とする磁気記録媒体は、磁
性粉をバインダと共に塗布、硬化した層を磁気記録層と
する磁気記録媒体よりも磁気記録特性を優れたものとす
ることができるが、磁気記録層である強磁性金属薄膜が
腐食し易いといった問題がある。(Prior art) A magnetic recording medium in which a ferromagnetic metal thin film is used as a magnetic recording layer has better magnetic recording characteristics than a magnetic recording medium in which magnetic powder is coated with a binder and a hardened layer is used as the magnetic recording layer. However, there is a problem that the ferromagnetic metal thin film that is the magnetic recording layer is easily corroded.
従来、この種の磁気記録媒体の磁気記録層である強磁性
金属薄膜に対する耐食性の改良のため、この強磁性金属
薄膜の表面に保護膜を形成することが検討されたが、表
面に保護膜を設けると、スペーシングロスにより出力の
低下が発生する。そこで耐食性の良好なＮｉＣｒ合金膜
を保護膜とする磁気記録媒体（特開昭５３−７３１０８
号）等が提案されている。Conventionally, in order to improve the corrosion resistance of the ferromagnetic metal thin film that is the magnetic recording layer of this type of magnetic recording medium, it has been considered to form a protective film on the surface of the ferromagnetic metal thin film. If provided, a decrease in output will occur due to spacing loss. Therefore, a magnetic recording medium using a NiCr alloy film with good corrosion resistance as a protective film (Japanese Unexamined Patent Publication No. 53-73108)
No.) etc. have been proposed.
他方、このような強磁性金属薄膜を磁気記録層とする磁
気記録媒体については、この強磁性金属薄膜と非磁性基
板との間に、耐食性の改良を目的とするものではないが
、チタン金属薄膜等の下地層を形成した磁気記録媒体（
特開昭５８−７７０２４号）が提案されている。On the other hand, in a magnetic recording medium having such a ferromagnetic metal thin film as a magnetic recording layer, a titanium metal thin film is placed between the ferromagnetic metal thin film and the nonmagnetic substrate, although this is not intended to improve corrosion resistance. Magnetic recording media with underlayers such as (
JP-A No. 58-77024) has been proposed.
（発明が解決しようとする課題）
磁気記録層である強磁性金属薄膜が腐食すると、飽和磁
化や再生出力等が低下するなどの問題がある。(Problems to be Solved by the Invention) When the ferromagnetic metal thin film that is the magnetic recording layer corrodes, there are problems such as a decrease in saturation magnetization, reproduction output, etc.
また、上述したように磁気記録層である強磁性金属薄膜
の上に保護膜を形成すると、ＮｉＣｒ合金膜を保護膜と
した場合にもこの層の磁化が小さいため磁気記録媒体の
磁気記録特性、特に再生出力の低下が生じ、磁気記録層
を金属薄膜としたことのメリットが大幅に削減されるこ
ととなる。In addition, as mentioned above, when a protective film is formed on the ferromagnetic metal thin film that is the magnetic recording layer, the magnetic recording properties of the magnetic recording medium are In particular, the reproduction output decreases, and the advantages of using a metal thin film as the magnetic recording layer are significantly reduced.
従って、強磁性金属薄膜を磁気記録層とする磁気記録媒
体においては、経時において飽和磁化や再生出力等が安
定して高い水準に維持される磁気記録媒体が望まれてい
る。Therefore, in a magnetic recording medium having a magnetic recording layer made of a ferromagnetic metal thin film, a magnetic recording medium is desired in which saturation magnetization, reproduction output, etc. are stably maintained at a high level over time.
（課題を解決するための手段）
本発明は上記課題を解決するため、非磁性基板と磁気記
録層である強磁性金属薄膜との間に膜厚が略０．０１μ
ｍ乃至１μｍのチタン酸化物薄膜を形成して磁気記録媒
体を構成したものである。(Means for Solving the Problems) In order to solve the above problems, the present invention provides a film thickness of approximately 0.01 μm between a nonmagnetic substrate and a ferromagnetic metal thin film serving as a magnetic recording layer.
A magnetic recording medium is constructed by forming a titanium oxide thin film with a thickness of 1 to 1 μm.
ここで、本発明の磁気記録媒体に使用される非磁性基板
としては、ポリエステル、ポリイミド、ポリアミド、ポ
リプロピレン、ポリカーボネイト等のプラスチック、あ
るいはアルミニウム、銅等の非磁性金属などからなるも
のが挙げられる。Here, examples of the nonmagnetic substrate used in the magnetic recording medium of the present invention include those made of plastics such as polyester, polyimide, polyamide, polypropylene, and polycarbonate, or nonmagnetic metals such as aluminum and copper.
また、磁気記録層を構成する強磁性金属としては、例え
ばＦｅ、Ｃｏ、Ｎｉ及びこれ等の少なくとも一種を含む
Ｃｏ−Ｃｒ合金等の合金、並びにこれ等の酸化物が挙げ
られる。Examples of the ferromagnetic metal constituting the magnetic recording layer include Fe, Co, Ni, alloys such as Co-Cr alloy containing at least one of these, and oxides of these.
そして本発明の磁気記録媒体は、例えば非磁性基板上に
真空蒸着法、スパッタリング法、イオンブレーティング
法、メツキ法等によりチタン金属薄膜を形成した後にこ
のチタン金属薄膜を酸化させるか、あるいは酸素雰囲気
中でチタン金属を真空蒸着したりスパッタリングしたり
することによりチタン酸化物薄膜を形成し、しかる後、
チタン金属薄膜を形成するのと同様の薄膜形成方法によ
って磁気記録層である強磁性金属薄膜を形成することに
よりて製造することができる。The magnetic recording medium of the present invention can be produced by forming a titanium metal thin film on a non-magnetic substrate by vacuum evaporation, sputtering, ion blating, plating, etc., and then oxidizing the titanium metal thin film, or by oxidizing the titanium metal thin film, or in an oxygen atmosphere. A titanium oxide thin film is formed by vacuum evaporating or sputtering titanium metal in the chamber, and then
It can be manufactured by forming a ferromagnetic metal thin film as a magnetic recording layer using a thin film forming method similar to that used for forming a titanium metal thin film.
（作用）
上記本発明の構成によれば、チタン酸化物薄膜の膜厚が
略０．０１μｍ以上の場合には磁気記録層である強磁性
金属薄膜の腐食の進行が抑制される。(Function) According to the configuration of the present invention described above, when the thickness of the titanium oxide thin film is approximately 0.01 μm or more, the progress of corrosion of the ferromagnetic metal thin film that is the magnetic recording layer is suppressed.
この腐食抑制のメカニズムは明らかでないが、強磁性金
属薄膜の腐食の進行にその下地の物理的、化学的状態が
大きく影響していることが示唆される。これに対し、チ
タン酸化物薄膜の膜厚が０．０１μｍ未満の場合には上
記腐食抑制の効果がなく、１μｍを越える場合には磁気
記録媒体の表面にある強磁性金属薄膜が傷付き易いもの
となる。Although the mechanism of this corrosion inhibition is not clear, it is suggested that the underlying physical and chemical conditions greatly influence the progress of corrosion of ferromagnetic metal thin films. On the other hand, if the thickness of the titanium oxide thin film is less than 0.01 μm, it will not have the above corrosion inhibiting effect, and if it exceeds 1 μm, the ferromagnetic metal thin film on the surface of the magnetic recording medium will be easily damaged. becomes.
他方、非磁性基板と磁気記録層である強磁性金属薄膜と
の間に例えばチタン金属薄膜やアルミニウム金属薄膜を
形成した場合にはチタン酸化物薄膜を形成した場合に比
較して強磁性金属薄膜の腐食の進行を抑制する効果が数
段落ちる。On the other hand, when a titanium metal thin film or an aluminum metal thin film is formed between the nonmagnetic substrate and the ferromagnetic metal thin film that is the magnetic recording layer, the ferromagnetic metal thin film becomes smaller than when a titanium oxide thin film is formed. The effect of suppressing the progress of corrosion is lowered by several levels.
（実施例） 以下に実施例を示し、本発明を更に詳しく説明する。(Example) EXAMPLES The present invention will be explained in more detail with reference to Examples below.
〈実施例〉
図面は本発明に係る磁気記録媒体を示すもので、この磁
気記録媒体は非磁性基板１とこの上の磁気記録層である
強磁性金属薄膜２との間に膜厚が略０．Ｏ１μｍ〜１μ
ｍのチタン酸化物薄膜３が形成され、非磁性基板ｉ上に
チタン酸化物薄膜３と強磁性金属薄膜２とを順次積層し
た構成となっている。<Example> The drawing shows a magnetic recording medium according to the present invention, and this magnetic recording medium has a film thickness of approximately 0 between a nonmagnetic substrate 1 and a ferromagnetic metal thin film 2 which is a magnetic recording layer thereon. ．． O1μm～1μ
A titanium oxide thin film 3 of m is formed, and the titanium oxide thin film 3 and a ferromagnetic metal thin film 2 are sequentially laminated on a nonmagnetic substrate i.
この種の磁気記録媒体は以下のようにして製造すること
ができる。This type of magnetic recording medium can be manufactured as follows.
即ち、真空槽を１ ｘ １０−５Ｔｏｒｒに排気した後
、真空槽中に酸素を真空槽の内部が一定の真空度５ Ｘ
１０−’Ｔｏｒｒになるように入れ、反応蒸着法によ
り膜厚０，１μｍの酸化チタン薄膜３を非磁性基板１で
あるポリエステルベースフィルム上に形成する。次ぎに
真空槽中の酸素を不活性ガスの例えばＡｒで置換して再
び真空槽の内部の真空度をＩ Ｘ １０−’Ｔｏｒｒと
した後、得られた酸化チタン薄膜３上にＮｉを２０ａｔ
％含むＣｏＮｉ合金薄膜を斜方蒸着法により形成し、長
尺フィルム状の実施例の磁気記録媒体を形成する。That is, after the vacuum chamber is evacuated to 1 x 10-5 Torr, oxygen is introduced into the vacuum chamber to maintain a constant vacuum level of 5 x
A thin titanium oxide film 3 having a thickness of 0.1 μm is formed on a polyester base film, which is a nonmagnetic substrate 1, by a reactive vapor deposition method. Next, the oxygen in the vacuum chamber is replaced with an inert gas such as Ar, and the degree of vacuum inside the vacuum chamber is set to I x 10-' Torr again.
% CoNi alloy thin film is formed by an oblique evaporation method to form a long film-shaped magnetic recording medium of the example.
〈比較例１〉
酸素を入れずに（反応蒸着を行なわずに）蒸着を行ない
同様の膜厚のチタン金属薄膜を非磁性基板１上に形成し
た他は上記実施例と同様にして比較例１の磁気記録媒体
を得た。<Comparative Example 1> Comparative Example 1 was carried out in the same manner as in the above example except that a titanium metal thin film of the same thickness was formed on the non-magnetic substrate 1 by performing vapor deposition without adding oxygen (without performing reactive vapor deposition). A magnetic recording medium was obtained.
〈比較例２〉
上記実施例と同様にして酸化チタン薄膜３の膜厚が０．
００５μｍである比較例２の磁気記録媒体を得た。<Comparative Example 2> The thickness of the titanium oxide thin film 3 was set to 0.
A magnetic recording medium of Comparative Example 2 having a diameter of 0.005 μm was obtained.
〈比較例３〉
上記実施例と同様にして酸化チタン薄膜３の膜厚が１．
５μｍである比較例３の磁気記録媒体を得た。<Comparative Example 3> The thickness of the titanium oxide thin film 3 was set to 1.5 mm in the same manner as in the above embodiment.
A magnetic recording medium of Comparative Example 3 having a thickness of 5 μm was obtained.
〈比較例４〉
上記実施例における酸化チタン薄膜３の形成工程を省略
して非磁性基板１上に直接強磁性金属薄膜２を形成した
比較例４の磁気記録媒体を得た。<Comparative Example 4> A magnetic recording medium of Comparative Example 4 was obtained in which the ferromagnetic metal thin film 2 was directly formed on the nonmagnetic substrate 1 by omitting the step of forming the titanium oxide thin film 3 in the above example.
く比較例５〉
チタン金属薄膜の代りにアルミニウム金属薄膜を形成し
た他は比較例１と同様にして比較例５の磁気記録媒体を
得た。Comparative Example 5 A magnetic recording medium of Comparative Example 5 was obtained in the same manner as Comparative Example 1 except that an aluminum metal thin film was formed instead of the titanium metal thin film.
〈比較例６〉
比較例４の磁気記録媒体の強磁性金属薄膜２上にＣｒを
１５ａｔ％含むＮｉＣｒ合金薄膜を形成してこのＮｉＣ
ｒ合金薄膜を保護膜とする比較例６の磁気記録媒体を得
た。<Comparative Example 6> A NiCr alloy thin film containing 15 at% Cr was formed on the ferromagnetic metal thin film 2 of the magnetic recording medium of Comparative Example 4.
A magnetic recording medium of Comparative Example 6 was obtained using an r alloy thin film as a protective film.
以上の実施例及び比較例１〜６の磁気記録媒体の１週間
６０℃９０％環境下に放置した後の飽和磁化Ｍｓ及びの
製造直後の４ＭＨ，の正弦波を記録した時の再生出力、
並びに堅牢性（磁気記録媒体の表面に０．０５ｍ ｍ
Ｒのサファイヤ針を１００ｇ荷重をかけて接触させ、２
００ ｍｍ／ｍ ｉ ｎ（７）速度テ引っ張った時の顕
微鏡で観察した傷付き具合）を測定し、飽和磁化の減少
率ΔＭ５と実施例を基準とした再生出力の低下（ｄＢ）
、及び傷の有無で堅牢性を評価した。The reproduction output when the saturation magnetization Ms of the magnetic recording media of the above Examples and Comparative Examples 1 to 6 was left in a 60°C 90% environment for one week and a 4MH sine wave immediately after manufacture was recorded.
and robustness (0.05 mm on the surface of the magnetic recording medium)
Contact the R sapphire needle with a load of 100g,
00 mm/min (7) The extent of scratches observed under a microscope when pulled at a speed of 0.00 mm/min (7) was measured, and the saturation magnetization reduction rate ΔM5 and the reduction in reproduction output (dB) based on the example were measured.
The robustness was evaluated based on the presence or absence of scratches.
以上の結果を表に示す。The above results are shown in the table.
（発明の効果）
上記表から明らかなように、本発明の磁気記録媒体は、
非磁性基板上に強磁性金属薄膜を形成した磁気記録媒体
、非磁性基板と磁気記録層である強磁性金属薄膜との間
にチタン酸化物薄膜以外の例えばチタン金属薄膜やアル
ミニウム金属薄膜を形成した磁気記録媒体、従来の保護
膜、例えばＮｉＣｒ合金膜を磁気記録層である強磁性金
属薄膜上に形成した磁気記録媒体、及びチタン酸化物薄
膜の膜厚が本発明範囲から外れた磁気記録媒体に比較し
て経時における飽和磁化の減少及び再生出力が小さく、
またチタン酸化物薄膜の膜厚が本発明範囲を越える磁気
記録媒体のように堅牢性が低下することもない。(Effects of the Invention) As is clear from the above table, the magnetic recording medium of the present invention has:
A magnetic recording medium in which a ferromagnetic metal thin film is formed on a non-magnetic substrate, in which a titanium metal thin film or an aluminum metal thin film other than a titanium oxide thin film is formed between the non-magnetic substrate and the ferromagnetic metal thin film that is the magnetic recording layer. Magnetic recording media, magnetic recording media in which a conventional protective film, such as a NiCr alloy film, is formed on a ferromagnetic metal thin film as a magnetic recording layer, and magnetic recording media in which the thickness of the titanium oxide thin film is outside the range of the present invention. In comparison, the decrease in saturation magnetization over time and the reproduction output are small,
Further, the robustness does not deteriorate as in magnetic recording media in which the thickness of the titanium oxide thin film exceeds the range of the present invention.
このように、本発明によれば、経時における飽和磁化特
性、再生出力及び堅牢性がともに安定して高い水準に維
持される磁気記録媒体が提供される。As described above, the present invention provides a magnetic recording medium in which saturation magnetization characteristics, reproduction output, and robustness are all stably maintained at high levels over time.
図面は本発明に係る磁気記録媒体を示す断面図である。 １・・・非磁性基板、 ２・・・強磁性金属薄膜、 ３・・・チ タン酸化物薄膜。 特 許 出 願 人 日本ビクター株式会社 The drawing is a sectional view showing a magnetic recording medium according to the present invention. 1...Nonmagnetic substrate, 2...Ferromagnetic metal thin film, 3...chi Tan oxide thin film. Special permission Out wish Man Japan Victor Co., Ltd.
Claims (1)
媒体において、前記非磁性基板と強磁性金属薄膜との間
に膜厚が略０．０１μｍ乃至１μｍのチタン酸化物薄膜
を形成したことを特徴とする磁気記録媒体。In a magnetic recording medium formed by forming a ferromagnetic metal thin film on a non-magnetic substrate, a titanium oxide thin film having a thickness of about 0.01 μm to 1 μm is formed between the non-magnetic substrate and the ferromagnetic metal thin film. A magnetic recording medium characterized by:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1860490A JPH03224119A (en) | 1990-01-29 | 1990-01-29 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1860490A JPH03224119A (en) | 1990-01-29 | 1990-01-29 | Magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03224119A true JPH03224119A (en) | 1991-10-03 |
Family
ID=11976248
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1860490A Pending JPH03224119A (en) | 1990-01-29 | 1990-01-29 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03224119A (en) |
-
1990
- 1990-01-29 JP JP1860490A patent/JPH03224119A/en active Pending
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