Patent US4913933A successfully refreshed from Google Patents.
US4913933A
Expired / Lapsed
US
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Method for preparing magnetic recording medium
Assignee: Canon Inc
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Filing: 1988-12-13
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Granted: 1990-04-03
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Expires: 2008-12-13
Abstract
Abstract A method for preparing a magnetic recording medium comprises delivering a substrate from a delivery roller, passing the substrate through one or a plurality of conveying rollers and forming a magnetic recording layer on said substrate by the physical vapor deposition method in the course of running along the circumferential surface of a rotatory drum, characterized in that said substrate is heated between the delivery roller and the conveying roller or between a conveying roller and another conveying roller, and the conveying roller through which said substrate passes after heating is made an expander roller.
Inventors
- 👤 Yuji Kasanuki
- 👤 Takayuki Yagi
- 👤 Kenji Suzuki
- 👤 Hiroshi Takagi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 13:39
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; G11B5/85
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
95 words
A method for preparing a magnetic recording medium comprising delivering a substrate from a delivery roller, passing the substrate through one or a plurality of conveying rollers and forming a magnetic recording layer on said substrate by the physical vapor deposition method in the course of running along the circumferential surface of a rotatory drum, characterized in that said substrate is heated between the delivery roller and the conveying roller or between a conveying roller and another conveying roller, and the conveying roller through which said substrate passes after heating is made an expander roller.
Claim 2
Independent Claim
95 words
A method for preparing a magnetic recording medium comprising delivering a substrate from a delivery roller, passing the substrate through one or a plurality of conveying rollers and forming a magnetic recording layer on said substrate by the physical vapor deposition method in the course of running along the circumferential surface of a rotatory drum, characterized in that said substrate is heated between the delivery roller and the conveying roller or between a conveying roller and another conveying roller, and the conveying roller through which said substrate passes after heating is made an expander roller.
Claim 3
Dependent Claim
15 words
A method according to claim 1, wherein said substrate is either polyethyleneterephthalate, polyimide or aramide.
Claim 4
Dependent Claim
15 words
A method according to claim 1, wherein said expander roller is formed of a rubber.
Claim 5
Dependent Claim
19 words
A method according to claim 1, wherein said magnetic recording layer is formed by the vacuum vapor deposition method.
Claim 6
Dependent Claim
17 words
A method according to claim 1, wherein said magnetic recording layer is formed by the sputtering method.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-04-02 | 1993-10-02 | 1994-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-02 | 1997-10-02 | 1998-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-02 | 2001-10-02 | 2002-04-03 | $7700.00 | Window Closed / Lapsed |