EP0432536A2
Expired / Lapsed
EP
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Magnetic recording medium and method for making it
Assignee: Panasonic Holdings Corp
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Filing: 1990-11-22
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Granted: —
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Expires: 2010-11-22
Abstract
Abstract In making a magnetic recording medium (5-11), a diamond-like carbon film (6) is formed stably with high product efficiency such as 200 ANGSTROM /sec, without occurrence of irregular discharge, and still improved durability and reduced head contamination are achieved by utilizing a.c. plasma discharge or a.c. plasma discharge superimposed by d.c. power and an lubricant film (5). <IMAGE>
Inventors
- 👤 Mikio Murai
- 👤 Kiyoshi Takahashi
- 👤 Masaru Odagiri
- 👤 Yoshiaki Kai
- 👤 Takashi Suzuki
- 👤 Toshiaki Kunieda
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 09:57
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/44; C23C16/50; C23C16/517; C23C16/22; C23C16/26; C23C16/505; C23C16/509; G; G11; G11B; G11B5/00; G11B5/62; G11B5/72; G11B5/725; G11B5/7253; G11B5/726; G11B5/7262; G11B5/7264; G11B5/7266; Y; Y10; Y10S; Y10S427/00; Y10S427/103; Y10S427/106; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/24; Y10T428/24355; Y10T428/24372; Y10T428/30; Y10T428/31504; Y10T428/31678
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
102 words
A method for making a magnetic recording medium comprising the steps of: forming a ferromagnetic metal thin film (8) on a substrate (10), forming a plasma polymer film (7) on said ferromagnetic metal thin film (8), forming a diamond-like carbon film (6) on said plasma polymer film (7) by plasma CVD method utilizing a.c. power (voltage Vac) in the frequency range of 80Hz to 200kHz which has peak voltage more than +500V and hydrocarbon having at least 3 carbon atoms as material, and forming a lubricant film (5) on said diamond-like carbon film (6) by a coater or an organic deposition method.
Claim 2
Dependent Claim
35 words
A method for making a magnetic recording medium in accordance with claim 1, wherein said plasma CVD method further utilizies one inert gas selected from the group consisting of helium, neon, argon, Kr, xenon, radon.
Claim 3
Dependent Claim
35 words
A method for making a magnetic recording medium in accordance with claim 1, wherein said a.c. power is further superimposed by d.c. power at a superimposing ratio R(%) of and 20% ≦ R ≦ 70%.
Claim 4
Dependent Claim
60 words
A method for making a magnetic recording medium in accordance with claim 1, wherein said lubricant film (5) is formed by using one organic composition selected from the group consisting of: (a) partially fluorinated ester of alkyl carboxylic acid having a melting point below 5°C, and (b) partially fluorinated alkyl carboxylic acid having a melting point from 50°C to 90°C.
Claim 5
Dependent Claim
90 words
A magnetic recording medium comprising: a ferromagnetic metal thin film (8) formed on a substrate (10), a plasma polymer film (7) formed on said ferromagnetic metal thin film (8), a diamond-like carbon film (6) formed on said plasma polymer film, and a lubricant film (5) of one organic composition selected from the group consisting of: (a) partially fluorinated ester of alkyl carboxylic acid having a melting point below 5°C, and (b) partially fluorinated alkyl carboxylic acid having a melting point from 50°C to 90°C, on said diamond-like carbon film (6).
References Cited (Backward Citations)
No citation records indexed.
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