JPS6334721A - Magnetic recording medium - Google Patents
Magnetic recording mediumInfo
- Publication number
- JPS6334721A JPS6334721A JP17694986A JP17694986A JPS6334721A JP S6334721 A JPS6334721 A JP S6334721A JP 17694986 A JP17694986 A JP 17694986A JP 17694986 A JP17694986 A JP 17694986A JP S6334721 A JPS6334721 A JP S6334721A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic recording
- recording medium
- film
- improved
- layer
- 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 31
- 229920006254 polymer film Polymers 0.000 claims abstract description 7
- 230000000694 effects Effects 0.000 abstract description 5
- 238000006243 chemical reaction Methods 0.000 abstract description 3
- 230000003247 decreasing effect Effects 0.000 abstract description 2
- 239000010410 layer Substances 0.000 description 27
- 239000010408 film Substances 0.000 description 14
- 238000000151 deposition Methods 0.000 description 5
- 230000001050 lubricating effect Effects 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 230000008021 deposition Effects 0.000 description 4
- 235000014113 dietary fatty acids Nutrition 0.000 description 4
- 229930195729 fatty acid Natural products 0.000 description 4
- 239000000194 fatty acid Substances 0.000 description 4
- 150000004665 fatty acids Chemical class 0.000 description 4
- -1 polyethylene terephthalate Polymers 0.000 description 4
- 239000011241 protective layer Substances 0.000 description 4
- 239000010409 thin film Substances 0.000 description 4
- 230000005294 ferromagnetic effect Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229910020630 Co Ni Inorganic materials 0.000 description 2
- 229910002440 Co–Ni Inorganic materials 0.000 description 2
- 235000021355 Stearic acid Nutrition 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 229910021385 hard carbon Inorganic materials 0.000 description 2
- 239000000314 lubricant Substances 0.000 description 2
- QIQXTHQIDYTFRH-UHFFFAOYSA-N octadecanoic acid Chemical compound CCCCCCCCCCCCCCCCCC(O)=O QIQXTHQIDYTFRH-UHFFFAOYSA-N 0.000 description 2
- OQCDKBAXFALNLD-UHFFFAOYSA-N octadecanoic acid Natural products CCCCCCCC(C)CCCCCCCCC(O)=O OQCDKBAXFALNLD-UHFFFAOYSA-N 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229920000139 polyethylene terephthalate Polymers 0.000 description 2
- 239000005020 polyethylene terephthalate Substances 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- 238000004544 sputter deposition Methods 0.000 description 2
- 239000008117 stearic acid Substances 0.000 description 2
- 238000007740 vapor deposition Methods 0.000 description 2
- 229910001020 Au alloy Inorganic materials 0.000 description 1
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910020598 Co Fe Inorganic materials 0.000 description 1
- 229910002519 Co-Fe Inorganic materials 0.000 description 1
- 229910020676 Co—N Inorganic materials 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 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
- 239000004642 Polyimide Substances 0.000 description 1
- 239000004734 Polyphenylene sulfide Substances 0.000 description 1
- 235000009470 Theobroma cacao Nutrition 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 244000240602 cacao Species 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 229910052804 chromium Inorganic materials 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
- 230000007797 corrosion Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- NBVXSUQYWXRMNV-UHFFFAOYSA-N fluoromethane Chemical compound FC NBVXSUQYWXRMNV-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000003353 gold alloy Substances 0.000 description 1
- 125000005462 imide group Chemical group 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 239000010687 lubricating oil Substances 0.000 description 1
- 230000005415 magnetization Effects 0.000 description 1
- 229920003207 poly(ethylene-2,6-naphthalate) Polymers 0.000 description 1
- 229920002312 polyamide-imide Polymers 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920006267 polyester film Polymers 0.000 description 1
- 229920001225 polyester resin Polymers 0.000 description 1
- 239000004645 polyester resin Substances 0.000 description 1
- 239000011112 polyethylene naphthalate Substances 0.000 description 1
- 229920001721 polyimide Polymers 0.000 description 1
- 229920000069 polyphenylene sulfide Polymers 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 230000003746 surface roughness Effects 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
本発明は高密度磁気記録に適する磁気記録媒体に関する
ものである。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording medium suitable for high-density magnetic recording.
従来の技術
最近の記録技術の進歩により、単位面積当りの記録密度
が著しく向上し、磁気記録媒体は、表面が極めて平滑な
強磁性金属薄膜を磁気記録層とする蒸着テープ等の実用
化が強く望まれてきている。３従って今後の高密度化は
、磁気ヘッドと磁気記録媒体の摺動下で起る摩擦、摩耗
等の理解に関するトライポロジーの課題の現実的な解決
を前提とするとの認識が深まっている〔テレビジョン学
会誌、 ＶＯＬ、４０．Ａ６ （１９８６） ４７２頁
〕。Conventional technology Recent advances in recording technology have significantly improved the recording density per unit area, and the practical use of magnetic recording media such as vapor-deposited tapes whose magnetic recording layer is a ferromagnetic metal thin film with an extremely smooth surface is rapidly increasing. It is becoming desired. 3 Therefore, there is a growing recognition that future increases in density will be premised on realistic solutions to tribology issues related to understanding the friction, wear, etc. that occur when magnetic heads and magnetic recording media slide. Academic journal, VOL, 40. A6 (1986) 472 pages].
第２図は従来の磁気記録媒体の拡大断面図である。１は
ポリエステルフィルム、ＡＡ金合金の非磁性基板、２は
Ｃｏ−Ｎｉ−０斜め蒸着膜、Ｃｏ−Ｃｒ垂直磁化膜等の
磁気記録層、３はトップコート層、ヰは保護層、６は潤
滑層である。FIG. 2 is an enlarged sectional view of a conventional magnetic recording medium. 1 is a polyester film, a non-magnetic substrate made of AA gold alloy, 2 is a magnetic recording layer such as a Co-Ni-0 obliquely deposited film or a Co-Cr perpendicular magnetization film, 3 is a top coat layer, I is a protective layer, and 6 is a lubricant. It is a layer.
従来、トップコート層は保護層の役割に期待するものと
して特開昭５４−１１３３０３号公報に開示されている
脂肪酸金属塩の蒸着膜による耐摩耗性の改善、特開昭５
７−１１６７７１号公報に開示されているイミド基を有
する高分子のスバ、ツタ膜、特開昭５８−７７０３１号
公報に開示されている高分子化合物をターゲットとして
スパッタする例、カーボンやＢ Ｎ 、 Ｍ ｏ Ｓ
２ 、 Ｓ ｉｏ ２等をスパッタや蒸着によシ薄膜化
する例、ダイアモンド状硬質炭素膜を用いる例（日本応
用磁気学会第４６回研究会資料）等が知られている。Conventionally, the top coat layer has been expected to play a role as a protective layer, as disclosed in JP-A-54-113303, which improves abrasion resistance by depositing a fatty acid metal salt film;
Examples of sputtering using a polymer compound having an imide group as disclosed in Japanese Patent Application Laid-Open No. 7-116771 using a polymer compound as a target, carbon, BN, M o S
Examples of thinning films such as S 2 and S io 2 by sputtering or vapor deposition, and examples of using a diamond-like hard carbon film (materials from the 46th research meeting of the Japanese Society of Applied Magnetics) are known.
また、潤滑目的の層として蒸着法、湿式塗布法等で、脂
肪酸、脂肪酸アミド等を被着する（例對−１ば特公昭５
６−３０６０９号公報）ものは、数多く試みられている
。In addition, as a layer for lubricating purposes, fatty acids, fatty acid amides, etc. are deposited by vapor deposition, wet coating, etc. (Example 1)
6-30609) have been attempted.
しかしながら上記した例は、耐摩耗性、走行性。However, the above examples are based on wear resistance and running properties.
防食効果等を十分満足できないため、積層化し、夫々の
役割分担で対策する考え方が増大している。Since the anti-corrosion effect cannot be fully satisfied, the idea of laminating layers and dividing the roles of each layer is increasing.
脂肪酸金属塩の吸着層上にフルオロカーボン系の潤滑層
を設けたもの（特開昭６１−１２０３３１号公報）、硬
質カーボン層の上に含フツ素潤滑油層を配したもの（特
開昭６１−１２６６２７号公報）、５ｔ−Ｎ−○系薄膜
上に潤滑層を形成したもの（特開昭６１−１３１２３１
号公報）等があげられる。One in which a fluorocarbon-based lubricant layer is provided on an adsorption layer of fatty acid metal salt (JP-A-61-120331), and one in which a fluorine-containing lubricating oil layer is provided on a hard carbon layer (JP-A-61-126627). (Japanese Unexamined Patent Publication No. 131231/1989), a lubricating layer formed on a 5t-N-○ thin film
Publication No.) etc.
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では、磁気記録層自身の耐摩
耗性、耐食性、走行性が十分でないため、保護層、潤滑
層から成るトップコート層の厚みがスペーシングロスに
よる短波長出力を低下させることになる大きさにならざ
るを得ないため、耐久信頼性を向上させると、電磁変換
特性が劣化するといった問題があシ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、磁気記
録層自身の耐久性を改善し、且つ雑音を改良することで
優れた電磁変換特性を有す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, with the above configuration, the wear resistance, corrosion resistance, and runnability of the magnetic recording layer itself are insufficient, so the thickness of the top coat layer consisting of the protective layer and the lubricating layer is shortened due to spacing loss. Since the size has to be such that the wavelength output is reduced, improving the durability and reliability results in deterioration of the electromagnetic conversion characteristics, which has been desired to be improved. The present invention was made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a magnetic recording medium having excellent electromagnetic conversion characteristics by improving the durability of the magnetic recording layer itself and reducing noise.
問題点を解決するための手段
上記問題点を解決するために本発明の磁気記録媒体は、
粒状突起を配した高分子フィルム上に最大入射角が７０
度以下の斜め蒸着膜を配したものである。Means for Solving the Problems In order to solve the above problems, the magnetic recording medium of the present invention comprises:
The maximum incident angle is 70° on a polymer film with granular protrusions.
A diagonally evaporated film with a thickness of less than
作 用
本発明の磁気記録媒体は上記した構成により、実効的な
接触面積が減少するので、磁気記録層自身の耐久性が改
良される。更に、突起部には大きな応力がかかるが、入
射角を７０度以下とすることで、突起部によるシャドウ
ィング作用が弱まり、付着強度が増大するのと、磁気的
な均一性が改善されるので変調ノイズが改良されること
になるのである。Function: Due to the above-described structure of the magnetic recording medium of the present invention, the effective contact area is reduced, so that the durability of the magnetic recording layer itself is improved. Furthermore, although large stress is applied to the protrusions, by setting the angle of incidence to 70 degrees or less, the shadowing effect of the protrusions is weakened, the adhesion strength is increased, and magnetic uniformity is improved. Modulation noise will be improved.
実施例
以下、図面を参照しながら、本発明の実施例について詳
説する。第１図は、本発明の実施例に係る磁気記録媒体
の拡大断面図である。同図において、６は厚みが１０μ
ｍのポリエチレンテレフタレートフィルムのごとき高分
子フィルムで触針式粗さ計で測定した表面粗さはＲａで
０．００３μｍである。７は微粒子として、Ｓ ｉ Ｏ
２（平均粒子径２００人）を平均密度５×１０９〔個／
ｃｒｔｉ ）含むポリエステル樹脂下塗り層で、８は
Ｃｏ −Ｎ ｉ （Ｃｏｃｏａを酸素雰囲気〔酸素分圧
２ ｘ １０−４（Ｔｏｒｒ） ］中で０．９〜１．２
５（μ／５８ｃ）の蒸着速度で斜め蒸着した。蒸着条件
として、蒸着速度と、入射角範囲をパラメータとして選
定した。EXAMPLES Hereinafter, examples of the present invention will be explained in detail with reference to the drawings. FIG. 1 is an enlarged sectional view of a magnetic recording medium according to an embodiment of the present invention. In the same figure, 6 has a thickness of 10μ
The surface roughness of a polymer film such as a polyethylene terephthalate film (Ra) measured using a stylus roughness meter is 0.003 μm. 7 as fine particles, S i O
2 (average particle size: 200 particles) with an average density of 5 x 109 [pieces/
crti), 8 is a polyester resin undercoat layer containing Co-Ni (Cocoa) in an oxygen atmosphere [oxygen partial pressure 2 x 10-4 (Torr)] of 0.9 to 1.2
Diagonal deposition was performed at a deposition rate of 5 (μ/58c). As the deposition conditions, the deposition rate and the incident angle range were selected as parameters.
膜厚はｏ、１５μｍ一定とした。強磁性金属薄膜８の上
に、厚み６０へのバー７０ロシクロブタンのプラズマ重
合膜９を配し、その上にステアリン酸の真空蒸着膜１ｏ
を４０人配して磁気テープとし、耐久性と雑音を比較し
た。耐久性は、スチル特性が短時間に磁気記録層の摩耗
特性、摩擦抵抗等を評価できるので、スチル特性に代表
させ、２０°Ｃ２ｏ％ＲＨで雑音が発生するまでのスチ
ル時間で比較した。雑音は８ミリビデオの標準仕様で、
２（止）の変調雑音を相対比較した。スチル時のテンシ
ョンは１６ノ一定とした。表に条件と評価結果をまとめ
た。The film thickness was kept constant at 15 μm. On the ferromagnetic metal thin film 8, a plasma-polymerized film 9 of rocyclobutane with a thickness of 60 mm is placed, and on top of that is a vacuum-deposited film 1 of stearic acid.
40 people were placed on the magnetic tape, and its durability and noise were compared. Durability was compared based on the still time until noise was generated at 20°C2o%RH, representing the still property since the wear property and frictional resistance of the magnetic recording layer can be evaluated in a short period of time. The noise is standard for 8mm video.
2 (stop) modulation noise was compared relative to each other. The tension during stilling was kept constant at 16 knots. The conditions and evaluation results are summarized in the table.
すｔ５
上記した媒体を用いて、８龍型ビデオを改造し、中心周
波数を０．６（μｍ）とした時は、更に雑音の改良が差
として大きく認識された。St5 When the 8-Ryu type video was modified using the above-mentioned medium and the center frequency was set to 0.6 (μm), the improvement in noise was even more noticeable as a difference.
なお、スチル時間を６０分程度に比較例を改善するには
プラズマ重合膜を１５０人、ステアリン酸膜を１２０八
にする必要があるが、このようにすると高周波出力が２
．５（ｄＢ）低下したことからも本発明品の有価値性は
明白である。In addition, in order to improve the comparative example to a still time of about 60 minutes, it is necessary to increase the plasma polymerized film to 150 and the stearic acid film to 120, but in this way the high frequency output will be 2
．． The value of the product of the present invention is clear from the fact that it decreased by 5 (dB).
上記実施例では、高分子フィルムとしてポリエチレンテ
レフタレートフィルムを用いたが他にポリエチレンナフ
タレート、ポリフェニレンサルファイド、ポリイミド、
ポリアミドイミド等でもよい。In the above examples, polyethylene terephthalate film was used as the polymer film, but other materials such as polyethylene naphthalate, polyphenylene sulfide, polyimide,
Polyamideimide or the like may also be used.
微粒子はＳｉＣ２の池にＣａ Ｃｏ３． Ｔ ｔ Ｏ２
，Ｆｅ３Ｏ４゜ポリエステル球等でもよく、ミミズ状隆
起と組み合わせたものでもよい。The fine particles are placed in a SiC2 pond with CaCo3. T t O2
, Fe3O4° polyester spheres, etc., or combinations with earthworm-like protuberances.
磁気記録層の材料としてはＣｏ−Ｎｉの他にＣｏ。The material for the magnetic recording layer is Co in addition to Co-Ni.
Ｃｏ−Ｆｅ 、Ｆｅ −Ａｇ 、Ｃｏ−Ｃｒ 、Ｃｏ
−Ｍｇ 、Ｃｏ −Ｍｏ 。Co-Fe, Fe-Ag, Co-Cr, Co
-Mg, Co-Mo.
Ｃｏ−Ｎｉ −Ｐ 、Ｃｏ−Ｎｉ −Ｒｕ 、Ｃｏ−Ｎ
ｆ−Ｐｒ 。Co-Ni-P, Co-Ni-Ru, Co-N
f-Pr.
Ｃｏ−Ｎｔ −Ａｕ 、Ｃｏ−Ｎｉ−Ｐｔ 等いずれ
でもよい。Any of Co-Nt-Au, Co-Ni-Pt, etc. may be used.
保護層、潤滑層については適宜最適化すればよい。なお
、磁気記録層を多層構成とする場合についてもそれぞれ
の層が本発明の要件を満たせば同一の作用効果を得るこ
とができる。The protective layer and lubricating layer may be optimized as appropriate. Note that even when the magnetic recording layer has a multilayer structure, the same effects can be obtained as long as each layer satisfies the requirements of the present invention.
発明の効果
以上のように本発明によれば、磁気記録層自身の耐久性
が向上し、かつ雑音も改良され、高密度磁気記録用とし
て浸れた磁気記録媒体を与えることができるといったす
ぐれた効果を得ることができるものである。Effects of the Invention As described above, according to the present invention, the durability of the magnetic recording layer itself is improved, the noise is also improved, and a magnetic recording medium capable of being used for high-density magnetic recording can be provided. This is something that can be obtained.
第１図は本発明の実施例に係る磁気記録媒体の拡大断面
図、第２図は従来の磁気記録媒体の拡大断面図である。
６・・・・高分子フィルム、７・・・・・下塗９層、８
・・・強磁性金属薄膜、９・・−保護膜、１０・・・潤
滑層。FIG. 1 is an enlarged sectional view 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. 6...Polymer film, 7...9 layers of undercoat, 8
... Ferromagnetic metal thin film, 9...-protective film, 10... lubricating layer.
Claims (1)
度以下の斜め蒸着膜を配して成ることを特徴とする磁気
記録媒体。The maximum incident angle is 70° on a polymer film with granular protrusions.
1. A magnetic recording medium comprising a diagonally deposited film having a thickness of less than 100 degrees.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17694986A JPS6334721A (en) | 1986-07-28 | 1986-07-28 | Magnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17694986A JPS6334721A (en) | 1986-07-28 | 1986-07-28 | Magnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6334721A true JPS6334721A (en) | 1988-02-15 |
Family
ID=16022544
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17694986A Pending JPS6334721A (en) | 1986-07-28 | 1986-07-28 | Magnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6334721A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57167122A (en) * | 1981-04-03 | 1982-10-14 | Hitachi Maxell Ltd | Magnetic recording medium |
-
1986
- 1986-07-28 JP JP17694986A patent/JPS6334721A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57167122A (en) * | 1981-04-03 | 1982-10-14 | Hitachi Maxell Ltd | Magnetic recording medium |
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