JPH0799571B2 - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPH0799571B2 JPH0799571B2 JP29107486A JP29107486A JPH0799571B2 JP H0799571 B2 JPH0799571 B2 JP H0799571B2 JP 29107486 A JP29107486 A JP 29107486A JP 29107486 A JP29107486 A JP 29107486A JP H0799571 B2 JPH0799571 B2 JP H0799571B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic recording
- recording medium
- film
- layer
- thin film
- 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.)
- Expired - Lifetime
Links
- 230000005291 magnetic effect Effects 0.000 title claims description 24
- 239000010419 fine particle Substances 0.000 claims description 7
- 239000010410 layer Substances 0.000 description 17
- 239000002184 metal Substances 0.000 description 9
- 229910052751 metal Inorganic materials 0.000 description 9
- 239000010409 thin film Substances 0.000 description 9
- 230000005294 ferromagnetic effect Effects 0.000 description 8
- -1 polyethylene terephthalate Polymers 0.000 description 8
- 239000010408 film Substances 0.000 description 7
- 238000007885 magnetic separation Methods 0.000 description 7
- 238000007740 vapor deposition Methods 0.000 description 6
- 229910052760 oxygen Inorganic materials 0.000 description 5
- 239000001301 oxygen Substances 0.000 description 5
- 229920006254 polymer film Polymers 0.000 description 5
- 238000005260 corrosion Methods 0.000 description 4
- 230000007797 corrosion Effects 0.000 description 4
- 229910020630 Co Ni Inorganic materials 0.000 description 3
- 229910002440 Co–Ni Inorganic materials 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 150000002500 ions Chemical class 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 229920000139 polyethylene terephthalate Polymers 0.000 description 3
- 239000005020 polyethylene terephthalate Substances 0.000 description 3
- 229910018553 Ni—O Inorganic materials 0.000 description 2
- 239000004642 Polyimide Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052758 niobium Inorganic materials 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229920001721 polyimide Polymers 0.000 description 2
- 239000011241 protective layer Substances 0.000 description 2
- 238000004544 sputter deposition Methods 0.000 description 2
- LRMSQVBRUNSOJL-UHFFFAOYSA-N 2,2,3,3,3-pentafluoropropanoic acid Chemical compound OC(=O)C(F)(F)C(F)(F)F LRMSQVBRUNSOJL-UHFFFAOYSA-N 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910020647 Co-O Inorganic materials 0.000 description 1
- 229910020704 Co—O Inorganic materials 0.000 description 1
- 229910020517 Co—Ti Inorganic materials 0.000 description 1
- 229910019092 Mg-O Inorganic materials 0.000 description 1
- 229910019395 Mg—O Inorganic materials 0.000 description 1
- 229910018104 Ni-P Inorganic materials 0.000 description 1
- 229910018536 Ni—P Inorganic materials 0.000 description 1
- 239000004962 Polyamide-imide Substances 0.000 description 1
- 239000004695 Polyether sulfone Substances 0.000 description 1
- 239000004734 Polyphenylene sulfide Substances 0.000 description 1
- 229910003481 amorphous carbon Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- ABDBNWQRPYOPDF-UHFFFAOYSA-N carbonofluoridic acid Chemical compound OC(F)=O ABDBNWQRPYOPDF-UHFFFAOYSA-N 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 229930195729 fatty acid Natural products 0.000 description 1
- 239000000194 fatty acid Substances 0.000 description 1
- 150000004665 fatty acids Chemical class 0.000 description 1
- 239000004811 fluoropolymer Substances 0.000 description 1
- 229920002313 fluoropolymer Polymers 0.000 description 1
- 238000010884 ion-beam technique Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 229910052762 osmium Inorganic materials 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 229920003207 poly(ethylene-2,6-naphthalate) Polymers 0.000 description 1
- 229920002312 polyamide-imide Polymers 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920006393 polyether sulfone Polymers 0.000 description 1
- 239000011112 polyethylene naphthalate Substances 0.000 description 1
- 229920000069 polyphenylene sulfide Polymers 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
Landscapes
- Magnetic Record Carriers (AREA)
Description
【発明の詳細な説明】 産業上の利用分野 本発明は、高密度磁気記録に適する強磁性金属薄膜を磁
気記録層とする磁気記録媒体に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording medium having a ferromagnetic metal thin film suitable for high density magnetic recording as a magnetic recording layer.
従来の技術 近年、磁気記録の高密度化への要求は、より記録波長を
短縮化する方向にあり、塗布型の磁気記録層に代って真
空蒸着，スパッタリング等の薄膜化技術により、Co−N
i,Co−Cr,Co−Ni−Ｏ等の強磁性金属薄膜を高分子フィ
ルム上に直接又は下地層を介して形成してなるいわゆる
金属薄膜型の磁気記録媒体の実用化が強く望まれてきて
いる〔例えば外国論文誌アイイーイーイー トランザク
ション オン マグネティクス（IEEE TRANSACTIONS
ON MAGNETICS）vol.MAG−21,NO−3,P.P.1217〜1220（1
985）参照〕。2. Description of the Related Art In recent years, there has been a demand for higher recording density in magnetic recording in order to further shorten the recording wavelength. In place of the coating type magnetic recording layer, thin film forming techniques such as vacuum deposition and sputtering are used to reduce the Co-content. N
Practical application of a so-called metal thin film type magnetic recording medium in which a ferromagnetic metal thin film of i, Co-Cr, Co-Ni-O or the like is formed on a polymer film directly or via an underlayer is strongly desired. [For example, foreign journals IEEE Transactions on Magnetics (IEEE TRANSACTIONS
ON MAGNETICS) vol.MAG-21, NO-3, PP1217-1220 (1
985)]].
強磁性金属薄膜を実用化する上で重要な物性は、磁気特
性，機械強度，耐食性等で、これまで数多くの，磁気記
録層自身，磁気記録層の製造方法等についての提案がな
されてきている。第２図はこれまで提案された磁気記録
媒体の代表例の拡大断面図で、第２図で１は、ポリエチ
レンテレフタレート，ポリイミド等の高分子フィルム
で、必要に応じて、表面に各種の凹凸形状を形成するた
め下塗り層を配したものもある。２は、米国特許第3342
632号及び第3342633号明細書等に述べられている斜め蒸
着法により形成されたCo,Fe,Co−Ni等をはじめとして、
スパッタリング法で形成されたCo−Cr等の強磁性金属薄
膜からなる磁気記録層で３は保護層で、脂肪酸，パーフ
ロロカルボン酸や、フロラズマ重合膜，非晶質炭素膜,M
oS2膜等から構成されている。Physical properties that are important for putting a ferromagnetic metal thin film into practical use are magnetic properties, mechanical strength, corrosion resistance, etc., and many proposals have been made so far regarding the magnetic recording layer itself, a method for manufacturing the magnetic recording layer, and the like. . FIG. 2 is an enlarged cross-sectional view of a typical example of a magnetic recording medium proposed so far. In FIG. 2, 1 is a polymer film such as polyethylene terephthalate or polyimide, and if necessary, various irregular shapes on the surface. In some cases, an undercoat layer is provided to form the. 2 is US Pat. No. 3342
Co, Fe, Co-Ni and the like formed by the oblique deposition method described in No. 632 and No. 3342633, etc.,
A magnetic recording layer 3 made of a ferromagnetic metal thin film such as Co-Cr formed by a sputtering method, 3 is a protective layer, which is a fatty acid, perfluorocarboxylic acid, a fluoropolymer film, an amorphous carbon film, M
It is composed of oS 2 film and so on.
〔特開昭61−77128号，同61−142523号、同61−139919
号等の公報、ジャーナル オブ アプライド フィジッ
クス（Journal of Applied Physics）vol.50,4285（197
9）、特開昭61−142525号、61−151835号等の公報等参
照〕 磁気記録層の改良は、磁気記録層自身の耐久性を向上す
るため、酸化層を利用することや（特公昭56−23208号
公報参照）窒化物を利用する〔ジャーナル オブ アプ
ライド フィジックス（Journal of Applied Physics）
vol53,6941（1982）参照〕か，磁気記録層は金属で構成
し〔特開昭61−77128号，同61−224127号，特公昭58−9
1号等の公報参照〕保護層で、金属薄膜に傷が入らない
ようにする方法が中心に検討さ８￥められている。[JP-A-61-77128, 61-142523, 61-139919
No., etc., Journal of Applied Physics vol.50,4285 (197
9), JP-A Nos. 61-142525 and 61-151835, etc.] In order to improve the durability of the magnetic recording layer, it is necessary to use an oxide layer in order to improve the durability of the magnetic recording layer. 56-23208) Utilizing nitride [Journal of Applied Physics]
vol53,6941 (1982)] or the magnetic recording layer is made of metal [JP-A-61-77128, JP-A-61-224127, JP-B-58-9].
See the gazette of No. 1 etc.] A protective layer has been mainly studied for preventing the metal thin film from being scratched.
発明が解決しようとする問題点 しかしながら上記した構成の範囲では、記録波長が0.8
μｍを下まわるようになると、保護膜に頼ると、スペー
シング損失で信号対雑音比（S/N）が低下する問題があ
った。又雑音や耐食性を改良するため、同種又は異種の
材料の積層構成〔特開昭57−133519,59−119534,59−11
9531,59−116933号公報等参照〕による改良も上記した
波長域では改善効果が不十分で、一層の改善が望まれて
いた。本発明は上記した事情に鑑みなされたもので、耐
久性とS/Nの両者を共に満足できる磁気記録媒体を提供
するものである。Problems to be Solved by the Invention However, in the range of the above configuration, the recording wavelength is 0.8
When the thickness falls below μm, there is a problem that the signal-to-noise ratio (S / N) decreases due to spacing loss when relying on the protective film. Further, in order to improve noise and corrosion resistance, a laminated structure of the same or different materials [JP-A-57-133519, 59-119534, 59-11
The improvement effect by the above-mentioned wavelength region is insufficient, and further improvement has been desired. The present invention has been made in view of the above circumstances, and provides a magnetic recording medium capable of satisfying both durability and S / N.
問題点を解決するための手段 本発明の磁気記録媒体は上記した問題点を解決するた
め、回転支持体に沿って形成された斜め蒸着膜が柱状微
粒子群から成り、該柱状微粒子群が厚み方向に磁気的に
分割されるようにしたものである。Means for Solving the Problems In order to solve the above-mentioned problems, the magnetic recording medium of the present invention comprises an obliquely deposited film formed along a rotary support, which is composed of a group of columnar particles, and the group of columnar particles is in the thickness direction. It is designed to be magnetically divided into.
作用 本発明の磁気記録媒体は上記した構成により、柱状微粒
子が従来の積層構成のように厚み方向に分割されないた
め、機械強度が低下しないため耐久性の低下を防ぐこと
ができる、一方では厚み方向に磁気的に分割されるた
め、雑音低下と感度向上がはかれるためS/Nとして改善
されるのである。The magnetic recording medium of the present invention has the above-mentioned constitution, and since the columnar fine particles are not divided in the thickness direction unlike the conventional laminated constitution, the mechanical strength is not lowered and the durability can be prevented from being lowered. Since it is magnetically divided into two, noise is reduced and sensitivity is improved, so the S / N is improved.
実 施 例 以下、図面に沿って本発明の実施例について詳しく説明
する。第１図は本発明の磁気記録媒体の要部拡大断面図
である。第１図で４は、ポリエチレンテレフタレート，
ポリエチレンナフタレート，ポリフェニレンサルファイ
ド，ポリイミド，ポリアミドイミド，ポリエーテルサル
フオン，ポリカーボネート等の高分子フィルムか形状付
与のための水溶性高分子，微粒子を含む樹脂等の下塗り
層を配した高分子フィルムで、５は強磁性金属薄膜構成
柱状微粒子で６は非磁性分離層で５を強磁性部I,7と強
磁性部II,8とに磁気的に分離するための層である。Example Hereinafter, an example of the present invention will be described in detail with reference to the drawings. FIG. 1 is an enlarged sectional view of a main part of a magnetic recording medium of the present invention. In FIG. 1, 4 is polyethylene terephthalate,
Polymer film such as polyethylene naphthalate, polyphenylene sulfide, polyimide, polyamide imide, polyether sulfone, polycarbonate, etc. Reference numeral 5 is a columnar fine particle composed of a ferromagnetic metal thin film, and 6 is a nonmagnetic separation layer for magnetically separating 5 into a ferromagnetic portion I, 7 and a ferromagnetic portion II, 8.
柱状微粒子は、円筒キャン，エンドレスベルト等の回転
支持体に沿って高分子フィルムを移動しながら斜め蒸着
することにより得られるもので、磁気分離のための非磁
性分離層形成は、斜め蒸着の開始から終了までの間に、
１回又は必要回数、集束したイオンビームを照射するの
が適当である。装置としては、従来の蒸着装置にイオン
照射機構を設ける必要があるが、２層以上の構成にする
従来法の多層化による磁気分離手法に比して、生産性に
も優れるものといえる。The columnar fine particles are obtained by oblique vapor deposition while moving a polymer film along a rotary support such as a cylindrical can or an endless belt. When forming a non-magnetic separation layer for magnetic separation, the oblique vapor deposition is started. From the end to
It is suitable to irradiate the focused ion beam once or a necessary number of times. As for the apparatus, it is necessary to provide an ion irradiation mechanism in the conventional vapor deposition apparatus, but it can be said that it is superior in productivity as compared with the conventional magnetic separation method by multi-layering having two or more layers.
本発明に用いることのできる材料は、Co,Co−Ni,Co−O,
Co−Os,Co−Ti,Co−Cr,Co−Mo,Co−Nb,Co−Ni−O,Co−
Ｂ−O,Co−Mg−O,Co−Cr−Nb,Co−Ni−Ｐ等で、非磁性
分離層形成は、酸素イオンが優れているが他に、耐食性
面，イオンの形成が効率よく出来る元素を選んでもよい
のは勿論である。Materials that can be used in the present invention, Co, Co-Ni, Co-O,
Co-Os, Co-Ti, Co-Cr, Co-Mo, Co-Nb, Co-Ni-O, Co-
With B-O, Co-Mg-O, Co-Cr-Nb, Co-Ni-P, etc., the non-magnetic separation layer formation is excellent in oxygen ions, but in addition, corrosion resistance and efficient formation of ions Of course, you may choose the element that can be done.
更に具体的な比較例と実施例での測定データから本発明
の意義についてみてみることにする。Further, the significance of the present invention will be examined based on the measured data in more specific comparative examples and examples.
厚み10μｍのポリエチレンテレフタレートフィルム上に
平均100Åのカーボン微粒子を30ケ／（μｍ）２配した
ものを直径1mの円筒キャン（キャン温度30℃）に沿わせ
て、75m/minで巻取りながら、入射角90度から30度まで
の斜め入射で蒸着を行った。蒸着時に酸素を６×10
-5（Torr）になるよう導入し、膜厚は0.15μｍ一定とし
た。蒸着はCo−Ni（Ni,20wt％）の電子ビーム蒸着で、
テープＡは、酸素イオンを入射角が49度の位置に120μA
/cm2,1.2KeVで照射したもので、非磁性分離層は約40Å
である。テープＢは、入射角60度と、44度の位置に夫々
1.2KeVで60μA/cm2,130μA/cm2の酸素イオンを照射した
もので、非磁性分離層は夫々60Å,35Åである。テープ
C,Dは酸素イオンをCrイオンに変えて、電流密度を0.6倍
にして実施したもので、テープＥは照射を全く行わなか
ったもので、テープＡ〜Ｅは８ミリ幅で表面にはいずれ
も約60Åのパーフロロプロピオン酸を真空蒸着した。テ
ープＡ〜Ｅを８ミリ仕様での輝度S/Nで相対比較した。
耐食性にからむ耐久性の評価は、60℃90％RHに22日間放
置後８ミリ仕様のPCMエラー率の変化で比較した。So along those arranged carbon fine particles having an average 100 Å 30 Quai / ([mu] m) 2 on a polyethylene terephthalate film having a thickness of 10μm to cylindrical can with a diameter of 1 m (the can temperature 30 ° C.), while taking up at 75 m / min, the incident Deposition was carried out with oblique incidence from an angle of 90 degrees to 30 degrees. 6 × 10 oxygen during vapor deposition
-5 (Torr) was introduced and the film thickness was kept constant at 0.15 μm. Vapor deposition is Co-Ni (Ni, 20 wt%) electron beam vapor deposition.
Tape A has 120 μA of oxygen ions at the incident angle of 49 degrees.
/ cm 2 , 1.2 KeV, non-magnetic separation layer is about 40 Å
Is. Tape B is at the incident angle of 60 degrees and 44 degrees, respectively.
60 .mu.A / cm 2 at 1.2KeV, which was irradiated with oxygen ions 130μA / cm 2, the non-magnetic separation layer respectively 60 Å, a 35 Å. tape
C and D were carried out by changing oxygen ions to Cr ions and increasing the current density by 0.6 times. Tape E was not irradiated at all, and tapes A to E were 8 mm wide and eventually on the surface. About 60Å perfluoropropionic acid was vacuum deposited. Tapes A to E were compared relative to each other with a luminance S / N in the 8 mm specification.
The evaluation of durability including corrosion resistance was made by comparing the change in PCM error rate of 8 mm specification after standing at 60 ° C. and 90% RH for 22 days.
輝度S/NはテープＥをＯ（dB）とすると初期値は、テー
プA,B,C,Dは夫々，＋2.9（dB），＋3.4（dB），＋3.1
（dB），＋4.0（dB）で、40℃85％RHで夫々165回くり返
し記録したテープを再生した時の165回目の再生S/Nはテ
ープA,B,C,D,Eは夫々＋2.7（dB），＋3.3（dB），＋3.0
（dB），＋4.1（dB），−2.4（dB）であった。Assuming that the tape S is O (dB), the brightness S / N is +2.9 (dB), +3.4 (dB), and +3.1 for tapes A, B, C, and D, respectively.
(DB) and +4.0 (dB), the 165th playback S / N when the tape recorded repeatedly at 165 times at 40 ° C and 85% RH was tape A, B, C, D, E respectively. +2.7 (dB), +3.3 (dB), +3.0
(DB), +4.1 (dB) and -2.4 (dB).
PCMエラー率は、初期値はテープA,B,C,D,Eが夫々２×10
-5,1×10-5,3×10-5,1.1×10-5,5×10-5で、60℃90％放
置後は、夫々,3×10-5,2×10-5,3.5×10-5,1.4×10-5,3
×10-4でいずれも実施例の優れた特性が確かめられる。Initial value of PCM error rate is 2 x 10 for tapes A, B, C, D and E respectively.
-5 , 1 × 10 -5 , 3 × 10 -5 , 1.1 × 10 -5 , 5 × 10 -5 at 60 ℃ 90%, 3 × 10 -5 , 2 × 10 -5 , 3.5 × 10 -5 , 1.4 × 10 -5 , 3
The excellent characteristics of the examples can be confirmed at × 10 -4 .
発明の効果 以上のように本発明によれば、耐久性とS/Nの両者共満
足せしめた磁気記録媒体が得られるといったすぐれた効
果がある。EFFECTS OF THE INVENTION As described above, according to the present invention, there is an excellent effect that a magnetic recording medium satisfying both durability and S / N is obtained.
第１図は本発明の実施例に係る磁気記録媒体の要部拡大
断面図、第２図は従来の磁気記録媒体の拡大断面図であ
る。 ４……高分子フィルム、５……強磁性金属薄膜構成柱状
微粒子、６……非磁性分離層。FIG. 1 is an enlarged sectional view of a main part of a magnetic recording medium according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of a conventional magnetic recording medium. 4 ... Polymer film, 5 ... Columnar fine particles composed of ferromagnetic metal thin film, 6 ... Non-magnetic separation layer.
Claims (1)
が柱状微粒子群から成り、該柱状微粒子が、厚み方向に
磁気的に分割されていることを特徴とする磁気記録媒
体。1. A magnetic recording medium characterized in that an obliquely vapor-deposited film formed along a rotary support comprises a group of columnar fine particles, and the columnar fine particles are magnetically divided in the thickness direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29107486A JPH0799571B2 (en) | 1986-12-05 | 1986-12-05 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29107486A JPH0799571B2 (en) | 1986-12-05 | 1986-12-05 | Magnetic recording medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63144412A JPS63144412A (en) | 1988-06-16 |
| JPH0799571B2 true JPH0799571B2 (en) | 1995-10-25 |
Family
ID=17764092
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29107486A Expired - Lifetime JPH0799571B2 (en) | 1986-12-05 | 1986-12-05 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0799571B2 (en) |
-
1986
- 1986-12-05 JP JP29107486A patent/JPH0799571B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63144412A (en) | 1988-06-16 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |