Patent US4547398A successfully refreshed from Google Patents.
US4547398A
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Method for manufacturing magnetic recording medium
Assignee: Panasonic Holdings Corp
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Filing: 1983-11-04
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Granted: 1985-10-15
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Expires: 2003-11-04
Abstract
Abstract A method for manufacturing a magnetic recording medium is proposed to determine an angle of incidence of vaporized atoms to be not more than 60° at an initial period of formation of a magnetic film by the vapor deposition method on a substrate which is travelling. The magnetic film contains Co and Cr as major constituents and has an axis of easy magnetization normal to the surface thereof.
Inventors
- 👤 Ryuji Sugita
- 👤 Toshiaki Kunieda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:35
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; G11B5/851; H; H01; H01F; H01F41/00; H01F41/14; H01F41/20
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
129 words
A method for forming a magnetic recording medium having a magnetic film containing Co and Cr as major constituents and having an axis of easy magnetization normal to a surface thereof, said method comprising vapor depositing vaporized atoms comprising said magnetic film on a substrate travelling through a deposition zone from an entrance to an exit thereof, the angle of incidence of vaporized atoms with respect to a line normal to the film surface at said entrance being not more than 60°, the angle of incidence of the vaporized atoms with respect to said substrate in an intermediate part of said deposition zone being substantially 0°, and the angle of incidence of the vaporized atoms at said exit being larger than the angle of incidence thereof at said entrance.
Claim 2
Independent Claim
129 words
A method for forming a magnetic recording medium having a magnetic film containing Co and Cr as major constituents and having an axis of easy magnetization normal to a surface thereof, said method comprising vapor depositing vaporized atoms comprising said magnetic film on a substrate travelling through a deposition zone from an entrance to an exit thereof, the angle of incidence of vaporized atoms with respect to a line normal to the film surface at said entrance being not more than 60°, the angle of incidence of the vaporized atoms with respect to said substrate in an intermediate part of said deposition zone being substantially 0°, and the angle of incidence of the vaporized atoms at said exit being larger than the angle of incidence thereof at said entrance.
Claim 3
Dependent Claim
20 words
A method according to claim 1, wherein said angle of incidence in said initial period is not more than 35°.
Claim 4
Dependent Claim
20 words
A method according to claim 1, wherein said angle of incidence in said initial period is not less than 35°.
Claim 5
Independent Claim
61 words
A method according to claims 1, 2 or 3, wherein a vapor deposition mask is disposed in the path of said vaporized atoms, the distance between said mask and said substrate being not more than 12 cm, said mask shielding the vaporized atoms of larger incident angles from the vapor sources at the initial period of formation of said magnetic film.
References Cited (Backward Citations)
US3342633A
Cited
US4220117A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-10-14 | 1989-04-15 | 1989-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-14 | 1993-04-15 | 1993-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-14 | 1997-04-15 | 1997-10-15 | $7700.00 | Window Closed / Lapsed |