EP0035894A1
Expired / Lapsed
EP
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Process for producing a magnetic recording medium
Assignee: Sekisui Chemical Co Ltd
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Filing: 1981-03-06
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Granted: —
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Expires: 2001-03-06
Abstract
Abstract A process for producing a magnetic recording medium comprises heating a crucible (11) containing a ferromagnetic material (17) in a high vacuum (2) corresponding to a pressure of 8 x 10<-><4> torr or lower thereby vaporizing the ferromagnetic material (17), impinging accelerated electrons from an electron radiation source (12) against the vapor particles to ionize them, and accelerating the resulting ionized vapor particles in an electric field (14) and impinging them against a substrate (5) composed of a non-magnetic material to form a ferromagnetic thin film thereon.
Inventors
- 👤 Shinsaku Nakata
- 👤 Yoichi Mikami
- 👤 Kazuhiro Fukaya
- 👤 Masahiro Hotta
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 22:58
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/22; C23C14/24; C23C14/32; G; G11; G11B; G11B5/00; G11B5/84; G11B5/8416; H; H01; H01F; H01F41/00; H01F41/14; H01F41/20
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
98 words
A process for producing a magnetic recording medium by ion-plating a non-magnetic substrate (5) with a ferromagnetic material (17), characterised by heating a crucible (11) containing ferromagnetic material (17) in a high vacuum (2) corresponding to a pressure of 8 x 10 -4 torr or lower thereby vaporizing the ferromagnetic material (17), impinging accelerated electrons from an electron radiation source (12) against the vapor particles to ionize them, and accelerating the resulting ionized vapor particles in an electric field and impinging them against a substrate (5) composed of a non-magnetic material to form a ferromagnetic thin film thereon.
Claim 2
Dependent Claim
98 words
A process for producing a magnetic recording medium by ion-plating a non-magnetic substrate (5) with a ferromagnetic material (17), characterised by heating a crucible (11) containing ferromagnetic material (17) in a high vacuum (2) corresponding to a pressure of 8 x 10 -4 torr or lower thereby vaporizing the ferromagnetic material (17), impinging accelerated electrons from an electron radiation source (12) against the vapor particles to ionize them, and accelerating the resulting ionized vapor particles in an electric field and impinging them against a substrate (5) composed of a non-magnetic material to form a ferromagnetic thin film thereon.
Claim 3
Dependent Claim
13 words
A process according to claim 1 wherein the ferromagnetic material (17) comprises cobalt.
Claim 4
Dependent Claim
33 words
A process according to claim 1 or 2 wherein the ferromagnetic material (17) is vaporised by impinging accelerated electrons both against a crucible (11) having electric conductivity and against the ferromagnetic material (17).
Claim 5
Dependent Claim
36 words
A process according to claim 1, 2 or 3, wherein the vapor particles of the ferromagnetic material (17) are ionized by an electron current of at least 30 mA released from be electron radiation source (12).
Claim 6
Dependent Claim
13 words
A process according to claim 3 wherein the conductive crucible (11) is grounded.
Claim 7
Dependent Claim
41 words
A process according to any one of claims 1 to 5 wherein the accelerated ionized vapor particles are impinged against the substrate (5), at an angle of incidence of at least 30° with respect to the perpendicular to the substrate (5).
Claim 8
Dependent Claim
20 words
A process according to any one of claims 1 to 6 wherein the substrate (5) is a polyethylene terephthalate film.
References Cited (Backward Citations)
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