US4660119A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flexible magnetic disk sheet
Assignee: Fujifilm Holdings Corp
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Filing: 1984-12-18
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Granted: 1987-04-21
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Expires: 2004-12-18
Abstract
Abstract A flexible magnetic disk sheet having a central circular hole is described, through which an apparatus for reading and writing is engaged, and enclosed in an jacket having a larger central circular hole exposing the hole of the disk sheet within the hole of the jacket, wherein a reinforcing plastic ring containing a solid lubricating agent is provided on the region of the flexible magnetic disk sheet immediately surrounding the central circular hole thereof.
Inventors
- 👤 Mikihiko Kato
- 👤 Shigeo Komine
- 👤 Kazuhiko Morita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:26
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/02; G11B23/03; G11B23/033; G11B23/0332; G11B23/0014; G11B23/0021; G11B23/0028; G11B23/0035
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
72 words
A flexible magnetic disk sheet having a central circular hole, (through which an apparatus for reading and writing is engaged,) and enclosed in a jacket having a larger central circular hole exposing the hole of the disk sheet within the hole of the jacket, wherein a reinforcing plastic ring containing a solid lubricating agent is provided on the region of the flexible magnetic disk sheet immediately surrounding the central circular hole thereof.
Claim 2
Dependent Claim
72 words
A flexible magnetic disk sheet having a central circular hole, (through which an apparatus for reading and writing is engaged,) and enclosed in a jacket having a larger central circular hole exposing the hole of the disk sheet within the hole of the jacket, wherein a reinforcing plastic ring containing a solid lubricating agent is provided on the region of the flexible magnetic disk sheet immediately surrounding the central circular hole thereof.
Claim 3
Dependent Claim
50 words
A flexible magnetic disk sheet as in claim 1, wherein the plastic forming the reinforcing plastic ring is selected from the group consisting of nylon 6, nylon 66, nylon 12, polyethylene terephthalate, a phenol resin, an epoxy resin, a poyacetal resin, a polyphenylene sulfide resin, a polycarbonate, and a polytetrafluoroethylene.
Claim 4
Dependent Claim
38 words
A flexible magnetic disk sheet as in claim 2, wherein the solid lubricating agent is selected from the group consisting of graphite, molybdenum disulfide, tungsten disulfide, boron nitride, graphite fluoride, a metal oxide, silicon nitride, and a metal.
Claim 5
Dependent Claim
40 words
A flexible magnetic disk sheet as in claim 3, wherein the solid lubricating agent is mixed in an amount of from 1 to 50 parts by weight per 100 parts by weight of the plastic forming the reinforcing plastic ring.
Claim 6
Dependent Claim
40 words
A flexible magnetic disk sheet as in claim 3, wherein the solid lubricating agent is mixed in an amount of from 5 to 10 parts by weight per 100 parts by weight of the plastic forming the reinforcing plastic ring.
Claim 7
Dependent Claim
22 words
A flexible magnetic disk sheet as in claim 3, wherein the thickness of the reinforcing ring is from 1 to 100 μm.
Claim 8
Dependent Claim
22 words
A flexible magnetic disk sheet as in claim 3, wherein the thickness of the reinforcing ring is from 2 to 50 μm.
Claim 9
Dependent Claim
38 words
A flexible magnetic disk sheet as in claim 1, wherein the solid lubricating agent is selected from the group consisting of graphite, molybdenum disulfide, tungsten disulfide, boron nitride, graphite fluoride, a metal oxide, silicon nitride, and a metal.
Claim 10
Dependent Claim
40 words
A flexible magnetic disk sheet as in claim 1, wherein the solid lubricating agent is mixed in an amount of from 1 to 50 parts by weight per 100 parts by weight of the platic forming the reinforcing plastic ring.
Claim 11
Dependent Claim
40 words
A flexible magnetic disk sheet as in claim 1, wherein the solid lubricating agent is mixed in an amount of from 5 to 10 parts by weight per 100 parts by weight of the plastic forming the reinforcing plastic ring.
Claim 12
Dependent Claim
22 words
A flexible magnetic disk sheet as in claim 1, wherein the thickness of the reinforcing ring is from 1 to 100 μm.
Claim 13
Dependent Claim
22 words
A flexible magnetic disk sheet as in claim 1, wherein the thickness of the reinforcing ring is from 2 to 50 μm.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-20 | 1990-10-20 | 1991-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-20 | 1994-10-20 | 1995-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-20 | 1998-10-20 | 1999-04-21 | $7700.00 | Window Closed / Lapsed |