Patent US4693934A successfully refreshed from Google Patents.
US4693934A
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Magnetic recording medium for image recording
Assignee: TDK Corp
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Filing: 1985-05-29
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Granted: 1987-09-15
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Expires: 2005-05-29
Abstract
Abstract Magnetic recording tape comprising a ferromagnetic thin film on a non-magnetic base and having good running stability and low output fluctuation, clogging, and dropout can be obtained by making the stiffness of the overall tape 0.149×wa.sup.3 /dxb=0.02 to 0.12 g mm wherein w: load (g) a: radius of tape ring (mm) b: tape width (mm) d: deformation of tape ring (mm) The stiffness in the above formula can be determined by the method described in the specification.
Inventors
- 👤 Masaharu Nishimatsu
- 👤 Hiroyuki Arioka
- 👤 Hideki Ishizaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:28
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/72; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
92 words
A ferromagnetic thin-film for image recording having a magnetic layer consisting of a ferromagnetic thin film formed on a base film and a backcoat layer formed on an opposite side thereof, said base film having a Young's modulus in the range of from about 280 to 800 kg/cm 2 and a thickness in the range of from 5 to 12 μm, said tape having a stiffness of 0.149×wa.sup.3 /d×b=0.02 to 0.12 g·mm wherein w: load (g) a: radius of tape ring (mm) b: tape width (mm) d: deformation of tape ring (mm).
Claim 2
Dependent Claim
92 words
A ferromagnetic thin-film for image recording having a magnetic layer consisting of a ferromagnetic thin film formed on a base film and a backcoat layer formed on an opposite side thereof, said base film having a Young's modulus in the range of from about 280 to 800 kg/cm 2 and a thickness in the range of from 5 to 12 μm, said tape having a stiffness of 0.149×wa.sup.3 /d×b=0.02 to 0.12 g·mm wherein w: load (g) a: radius of tape ring (mm) b: tape width (mm) d: deformation of tape ring (mm).
Claim 3
Dependent Claim
20 words
A ferromagnetic thin-film tape for image recording according to claim 1 wherein the stiffness is from 0.03 to 0.09 g·mm.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-09-14 | 1991-03-16 | 1991-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-09-14 | 1995-03-16 | 1995-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-09-14 | 1999-03-16 | 1999-09-15 | $7700.00 | Window Closed / Lapsed |