JPH0551967B2 - - Google Patents
Info
- Publication number
- JPH0551967B2 JPH0551967B2 JP62324603A JP32460387A JPH0551967B2 JP H0551967 B2 JPH0551967 B2 JP H0551967B2 JP 62324603 A JP62324603 A JP 62324603A JP 32460387 A JP32460387 A JP 32460387A JP H0551967 B2 JPH0551967 B2 JP H0551967B2
- Authority
- JP
- Japan
- Prior art keywords
- current
- roller
- recording medium
- magnetic recording
- magnetic 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.)
- Expired - Lifetime
Links
- 230000005291 magnetic effect Effects 0.000 claims description 42
- 238000004519 manufacturing process Methods 0.000 claims description 10
- 238000000034 method Methods 0.000 claims description 9
- 239000004065 semiconductor Substances 0.000 claims description 9
- 230000001681 protective effect Effects 0.000 claims description 7
- 239000010408 film Substances 0.000 description 23
- 239000002184 metal Substances 0.000 description 15
- 230000007547 defect Effects 0.000 description 11
- 239000010409 thin film Substances 0.000 description 9
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 8
- 229910052799 carbon Inorganic materials 0.000 description 8
- 238000005268 plasma chemical vapour deposition Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 5
- 230000007797 corrosion Effects 0.000 description 4
- 238000005260 corrosion Methods 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 229920000139 polyethylene terephthalate Polymers 0.000 description 4
- 239000005020 polyethylene terephthalate Substances 0.000 description 4
- 230000002159 abnormal effect Effects 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- -1 polyethylene terephthalate Polymers 0.000 description 2
- 230000003746 surface roughness Effects 0.000 description 2
- 238000007740 vapor deposition Methods 0.000 description 2
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 235000014113 dietary fatty acids Nutrition 0.000 description 1
- 230000005611 electricity Effects 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
- 230000005294 ferromagnetic effect Effects 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- BCCOBQSFUDVTJQ-UHFFFAOYSA-N octafluorocyclobutane Chemical compound FC1(F)C(F)(F)C(F)(F)C1(F)F BCCOBQSFUDVTJQ-UHFFFAOYSA-N 0.000 description 1
- 235000019407 octafluorocyclobutane Nutrition 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052573 porcelain Inorganic materials 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N titanium dioxide Inorganic materials O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 1
- 238000007738 vacuum evaporation Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Chemical Vapour Deposition (AREA)
- Manufacturing Of Magnetic Record Carriers (AREA)
Description
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
気記録媒体の製造方法に関するものであり、特に
高周波側での出力が高く、耐久性、耐蝕性に優れ
た磁気記録媒体の製造法を提供するものである。
従来の技術
金属薄膜型磁気記録媒体の耐久性、耐蝕性の向
上に対する保護膜形成法としては1塗布法、2ス
パツタ法、3有機蒸着法、4プラズマCVD法な
どが知られている。
この中で、プラズマCVD法は各種ガスをプラ
ズマ中で活性な状態に励起させて保護膜をつくる
方法である。。特に金属薄膜型の磁気記録媒体に
おいては、この金属面に通電する方法によるDC
プラズマCVD法が可能となり、より強固な保護
膜をつくることができる。
発明が解決しようとする問題点
しかしながら、磁気記録媒体に通電するローラ
ーがメタルローラーの場合、微弱な電流では欠陥
の発生はないが、流す電流が大きくなると電流の
集中により発熱し、この熱により非磁性基板であ
るポリエチレンテレフタレート(PET)が熱負
けして磁気記録媒体として使えなくなる。一方こ
れを防ぐため通電ローラーを絶縁性のもの又はア
ースにおとさないものにすると、ローラーと媒体
との間で電流が流れないため欠陥は発生しないが
媒体が帯電し、異常放電が発生するという問題が
あつた。すなわちDCプラズマCVD法によりたと
えばダイヤモンド状炭素膜を金属薄膜型磁気記録
媒体の保護膜として形成すると、この媒体のスチ
ル耐久性、走行耐久性を著しく向上できる。しか
し、流れる電流が大きくなるとメタルローラーに
おいては磁気テープ表面への電流の局部集中がお
こり、その発熱のためPETが局部的にダメージ
を受けて磁気テープには致命的欠陥となる。つま
り、ドロツプアウトの増加やヘツド目づまりの原
因となる。
この問題点を解決するため本発明は磁気記録媒
体上にDCプラズマCVD法により保護膜をつくる
際、この磁性層に相当量の電流を流しても媒体に
いかなる欠陥も発生しない製造方法を提供するも
のである。
問題点を解決するための手段
本発明は、成膜装置内に設置された通電ローラ
ーに、磁気記録媒体をこの媒体の磁性層が前記ロ
ーラーにふれるように巻出し、前記装置内にプラ
ズマを発生させて前記装置内を搬送されてくる前
記磁性層表面に電流を流して前記磁性層表面に保
護膜を形成するに際し、前記磁性層表面と接する
ローラーの表面を表面抵抗値が103Ω/cm2〜
106Ω/cm2の半導体としこのローラーの表面を通
して前記電流を逃がす磁気記録媒体の製造方法を
提供するものである。
作 用
この方法により特性の優れた磁気記録媒体とな
る。
実施例
以下、本発明の一実施例について図面を参照し
て説明する。
第1図はダイヤモンド状炭素膜の成膜装置の断
面略図であり、1が本発明の中心となる半導体的
表面抵抗値を持つた通電ローラーである。磁気記
録媒体の磁性層側がこの通電ローラーにふれるよ
うに巻出される。放電管5内で電圧をかけてプラ
ズマを発生させ搬送されてくる磁性層表面に電流
を流してダイヤモンド状炭素膜を形成する。その
電流の逃げ口が半導体的通電ローラーである。
まず、異常に大きい突起のない表面粗さのコン
トロールされた500mm幅のポリエチレンテレフタ
レートフイルム(たとえば表面最大粗さが300Å
〜400Å、中心線平均粗さが50Å〜150Åであり山
状突起の密度が1mm2当り104〜108個)上に真空蒸
着法により酸素を導入しながらCo80−Ni20の磁性
層を1800Å形成した後、この磁性層上へ真空度
0.1Torr、13.56MHzで高周波出力100Wの条件で
パーフルオロシクロブタンのプラズマ重合膜を厚
さ約20Å連続巻取式の装置で形成した後さらにこ
のプラズマ重合膜上へ表面抵抗値が103Ω/cm2〜
106Ω/cm2の範囲にあるもの例えばアルミナ−チ
タニア系、アモルフアスシリコン系または導電ゴ
ム等よりなる通電ローラー1により金属薄膜磁性
層2をマイナスとし、電極3をプラスとしてDC
プラズマCVD法によりダイヤモンド状炭素膜を
形成する。すなわち、電流は電極3から磁性層表
面を流れ、ローラー1の表面から逃げるように流
れ出る。この際、ガス組成はAr:CH4=1:6
として導入管4より導入し0.3Torrの真空度で約
100Åの厚みをつける。なお、通電ローラーとし
ては金属ローラーに半導体的材料をコーテイング
したものでも半導体材料だけでローラーを形成し
たものでも良い。5は放電管、6はキヤンであ
る。このようにしてできた磁気テープの単位面積
1m2当りの欠陥の数をカウントし、その差を確認
する。更に、このダイヤモンド状炭素膜上に塗布
法又は有機蒸着法により含フツ素脂肪酸を30Å付
着させた後スリツターにより8mm幅に裁断する。
このようにして作成された8mmビデオ用金属薄膜
型テープをコダツク社の8mmVTRでドロツプア
ウトの数を調べた。ドロツプアウトカウンターは
シバソク製を用い15μs、−16dB以上のものをカウ
ントした。その後23℃−10%の特殊環境におい
て、20gの加速テンシヨンでスチル耐久性を調べ
た。その結果を表−1に示す。
INDUSTRIAL APPLICATION FIELD The present invention relates to a method for manufacturing a magnetic recording medium using a ferromagnetic metal thin film as a magnetic recording layer, and particularly relates to a method for manufacturing a magnetic recording medium that has high output on the high frequency side and has excellent durability and corrosion resistance. It provides a manufacturing method. BACKGROUND ART Known methods for forming a protective film for improving the durability and corrosion resistance of metal thin film magnetic recording media include the 1-coating method, 2-sputtering method, 3-organic vapor deposition method, and 4-plasma CVD method. Among these, the plasma CVD method is a method of creating a protective film by exciting various gases to an active state in plasma. . In particular, in metal thin film type magnetic recording media, DC
Plasma CVD becomes possible, making it possible to create stronger protective films. Problems to be Solved by the Invention However, if the roller that conducts current to the magnetic recording medium is a metal roller, no defects will occur with a weak current, but if the current is large, heat will be generated due to the concentration of current, and this heat will cause non-performance. The magnetic substrate polyethylene terephthalate (PET) loses heat and can no longer be used as a magnetic recording medium. On the other hand, if the current-carrying roller is made of an insulating material or one that is not grounded to prevent this, no defects will occur because no current will flow between the roller and the medium, but the problem will be that the medium will be charged and abnormal discharge will occur. It was hot. That is, by forming, for example, a diamond-like carbon film as a protective film of a metal thin film type magnetic recording medium by the DC plasma CVD method, the still durability and running durability of this medium can be significantly improved. However, when the flowing current increases, the current locally concentrates on the surface of the magnetic tape in the metal roller, and the resulting heat causes local damage to the PET, resulting in a fatal defect in the magnetic tape. In other words, this causes an increase in dropouts and head clogging. In order to solve this problem, the present invention provides a manufacturing method that does not cause any defects in the medium even when a considerable amount of current is passed through the magnetic layer when a protective film is formed on the magnetic recording medium by the DC plasma CVD method. It is something. Means for Solving the Problems The present invention unwinds a magnetic recording medium onto a current-carrying roller installed in a film forming apparatus so that the magnetic layer of the medium touches the roller, and generates plasma within the apparatus. When forming a protective film on the surface of the magnetic layer by applying an electric current to the surface of the magnetic layer conveyed through the apparatus, the surface of the roller in contact with the surface of the magnetic layer is heated to a surface resistance value of 10 3 Ω/cm. 2 ~
The present invention provides a method for manufacturing a magnetic recording medium in which the current is released through the surface of a roller made of a semiconductor having a diameter of 10 6 Ω/cm 2 . Effect: This method provides a magnetic recording medium with excellent characteristics. Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view of a diamond-like carbon film forming apparatus, and numeral 1 indicates an energized roller having a semiconductor-like surface resistance value, which is the central feature of the present invention. The magnetic recording medium is unwound so that the magnetic layer side touches this current-carrying roller. A voltage is applied in the discharge tube 5 to generate plasma, and a current is applied to the surface of the magnetic layer being transported to form a diamond-like carbon film. The outlet for this current is the semiconductor energizing roller. First, a 500 mm wide polyethylene terephthalate film with a controlled surface roughness and no abnormally large protrusions (for example, a maximum surface roughness of 300 Å
~400 Å, center line average roughness of 50 Å to 150 Å, and density of mountain-like protrusions of 10 4 to 10 8 per mm 2 ), a magnetic layer of Co 80 −Ni 20 was deposited while introducing oxygen by vacuum evaporation. After forming 1800Å, apply vacuum to this magnetic layer.
After forming a plasma polymerized film of perfluorocyclobutane to a thickness of approximately 20 Å using a continuous winding device under the conditions of 0.1 Torr, 13.56 MHz, and high frequency output of 100 W, a surface resistance value of 10 3 Ω/cm was further applied onto the plasma polymerized film. 2 ~
In the range of 10 6 Ω/cm 2 For example, the metal thin film magnetic layer 2 is made negative by the current-carrying roller 1 made of alumina-titania, amorphous silicon, or conductive rubber, and the electrode 3 is made positive and DC is applied.
A diamond-like carbon film is formed by plasma CVD. That is, the current flows from the electrode 3 on the surface of the magnetic layer and flows out from the surface of the roller 1. At this time, the gas composition is Ar:CH 4 =1:6
Introduced from introduction pipe 4 as a vacuum at 0.3 Torr.
Add a thickness of 100Å. Note that the current-carrying roller may be a metal roller coated with a semiconductor material, or a roller formed only of a semiconductor material. 5 is a discharge tube, and 6 is a can. The number of defects per unit area of 1 m 2 of the magnetic tape thus produced was counted and the difference was confirmed. Furthermore, a fluorine-containing fatty acid of 30 Å is deposited on this diamond-like carbon film by a coating method or an organic vapor deposition method, and then cut into a width of 8 mm using a slitter.
The number of dropouts of the 8 mm video metal thin film tape thus prepared was examined using a Kodak 8 mm VTR. A dropout counter manufactured by Shibasoku was used to count the dropout counter for 15 μs and −16 dB or more. Thereafter, the still durability was examined under a special environment of 23°C - 10% under an accelerated tension of 20g. The results are shown in Table-1.
【表】【table】
【表】
第1表より明らかなようにサンプルNo.1〜2の
メタルローラーは通電量が多くなると欠陥が増え
てドロツプアウトの原因となつているがサンプル
No.3〜12の各種半導体的ローラーは通電量が1A
近くになつても欠陥は発生せず、ドロツプアウト
も安定している。なお、成膜速度は通電量にほぼ
比例し、通電量が多いほど生産性は向上する。
300mA以上の通電量では、使用するガスにより
ダイヤモンド状炭素膜の成膜スピードは異なる
が、おおよそ20m/min〜60m/minが可能であ
る。 また、欠陥が発生すれば上記の様にスチル
耐久性が極端に劣化するが、欠陥が発生しない限
りにおいては、通電量が多いほどスチル耐久性が
高くなる傾向も認められた。
このようにメタルローラーの表面を半導体材料
で50μm〜5000μmの厚みコーテイングするが半
導体材料でローラーをつくり、表面電気抵抗を
103Ω/cm2〜106Ω/cm2にすると、磁気テープとし
ての不都合がなく量産的スピードで金属薄膜型磁
気記録媒体の磁性面上にダイヤモンド状炭素膜を
形成することができる。
その結果、金属薄膜型磁器記録媒体のスチル耐
久性、耐蝕性を著しく向上させることが可能とな
る。なお、抵抗を介して金属ローラーからアース
におとす例(公開公報63−279426)もあり、これ
は大電流の全体的異常放電のエネルギーを低減さ
せる効果はあるが、電流の極所集中によるフイル
ムの熱負けに関しては全く効果がなく、本願のよ
うにローラーと磁性膜間での電流集中をさけるた
めにローラーの抵抗値を最適化しないかぎりフイ
ルム欠陥はなくならない。本発明のように、表面
抵抗値が103Ω/cm2〜106Ω/cm2の半導体ローラー
を介して電流を流すことにより、電流が分散され
て多数の接触点から流れるため、接触点1個あた
りの電流密度は低く発熱も少量のためフイルムの
熱負けは発生しない。
また、第1表はDCのみを印加した結果を示し
たが、本発明は電流集中による欠陥の発生を通電
ローラーの表面抵抗を最適化して解決するもので
あり、DCに限らず商用周波、高周波およびこれ
らを重畳した電流波形にも同様の効果が認められ
る。
発明の効果
以上のように本発明の製造方法によればスチル
耐久性、耐蝕性の著しく向上された金属薄膜型磁
気記録媒体を量産的スピードで製造することがで
きる。[Table] As is clear from Table 1, the metal rollers of samples No. 1 and 2 have more defects as the amount of current increases, causing dropouts.
The amount of current for various semiconductor rollers No. 3 to 12 is 1A.
No defects occur even at close range, and dropout is stable. Note that the film formation rate is approximately proportional to the amount of current applied, and the greater the amount of current applied, the higher the productivity.
When the current flow is 300 mA or more, the speed of forming the diamond-like carbon film varies depending on the gas used, but it is possible to form the diamond-like carbon film at approximately 20 m/min to 60 m/min. Furthermore, if a defect occurs, the still durability is extremely degraded as described above, but as long as no defect occurs, it was also observed that the still durability tends to increase as the amount of electricity is increased. In this way, the surface of the metal roller is coated with a semiconductor material to a thickness of 50 μm to 5000 μm, but the roller is made of semiconductor material to increase the surface electrical resistance.
When it is 10 3 Ω/cm 2 to 10 6 Ω/cm 2 , a diamond-like carbon film can be formed on the magnetic surface of a metal thin film magnetic recording medium at mass production speed without any inconvenience as a magnetic tape. As a result, it becomes possible to significantly improve the still durability and corrosion resistance of the metal thin film type porcelain recording medium. There is also an example of connecting a metal roller to ground via a resistor (Publication Publication No. 63-279426), which has the effect of reducing the overall energy of abnormal discharge of large currents, but it also causes damage to the film due to local concentration of current. There is no effect on heat loss, and film defects will not be eliminated unless the resistance value of the roller is optimized to avoid current concentration between the roller and the magnetic film as in the present application. As in the present invention, by passing current through a semiconductor roller with a surface resistance value of 10 3 Ω/cm 2 to 10 6 Ω/cm 2 , the current is distributed and flows from a large number of contact points. The current density per piece is low and the amount of heat generated is small, so the film does not suffer from heat loss. In addition, although Table 1 shows the results when only DC was applied, the present invention solves defects caused by current concentration by optimizing the surface resistance of the current-carrying roller. A similar effect is also observed in the current waveform obtained by superimposing these. Effects of the Invention As described above, according to the manufacturing method of the present invention, a metal thin film type magnetic recording medium with significantly improved still durability and corrosion resistance can be manufactured at mass production speed.
第1図は本発明の一実施例における磁気記録媒
体の製造方法を示すための構成図である。
1……通電ローラー、2……磁気記録媒体、3
……電極、4……ガス導入管、5……放電管、6
……キヤン。
FIG. 1 is a block diagram showing a method of manufacturing a magnetic recording medium in an embodiment of the present invention. 1... Current roller, 2... Magnetic recording medium, 3
... Electrode, 4 ... Gas introduction tube, 5 ... Discharge tube, 6
...Kyan.
Claims (1)
気記録媒体をこの媒体の磁性層が前記ローラーに
ふれるように巻出し、前記装置内にプラズマを発
生させて前記装置内を搬送されれくる前記磁性層
表面に電流を流して前記磁性層表面に保護膜を形
成するに際し、前記磁性層表面と接するローラー
の表面を表面抵抗値が103Ω/cm2〜106Ω/cm2の半
導体としこのローラーの表面を通して前記電流を
逃がすことを特徴とする磁気記録媒体の製造方
法。1. A magnetic recording medium is unwound onto a current-carrying roller installed in a film forming apparatus so that the magnetic layer of the medium touches the roller, plasma is generated in the apparatus, and the magnetic recording medium is transported through the apparatus. When forming a protective film on the surface of the magnetic layer by passing a current through the surface of the magnetic layer, the surface of the roller in contact with the surface of the magnetic layer is made of a semiconductor having a surface resistance value of 10 3 Ω/cm 2 to 10 6 Ω/cm 2 . A method for manufacturing a magnetic recording medium, characterized in that the current is released through the surface of the roller.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP32460387A JPH01166329A (en) | 1987-12-22 | 1987-12-22 | Production of magnetic recording medium |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP32460387A JPH01166329A (en) | 1987-12-22 | 1987-12-22 | Production of magnetic recording medium |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH01166329A JPH01166329A (en) | 1989-06-30 |
JPH0551967B2 true JPH0551967B2 (en) | 1993-08-04 |
Family
ID=18167665
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP32460387A Granted JPH01166329A (en) | 1987-12-22 | 1987-12-22 | Production of magnetic recording medium |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH01166329A (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6835523B1 (en) | 1993-05-09 | 2004-12-28 | Semiconductor Energy Laboratory Co., Ltd. | Apparatus for fabricating coating and method of fabricating the coating |
US5932302A (en) | 1993-07-20 | 1999-08-03 | Semiconductor Energy Laboratory Co., Ltd. | Method for fabricating with ultrasonic vibration a carbon coating |
JP3733878B2 (en) * | 2001-06-29 | 2006-01-11 | ソニー株式会社 | Metal thin film type magnetic recording medium and manufacturing method thereof |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62241137A (en) * | 1986-04-11 | 1987-10-21 | Matsushita Electric Ind Co Ltd | Method and apparatus for producing magnetic recording medium |
-
1987
- 1987-12-22 JP JP32460387A patent/JPH01166329A/en active Granted
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62241137A (en) * | 1986-04-11 | 1987-10-21 | Matsushita Electric Ind Co Ltd | Method and apparatus for producing magnetic recording medium |
Also Published As
Publication number | Publication date |
---|---|
JPH01166329A (en) | 1989-06-30 |
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