US4251843A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Disc jacket for retaining magnetic recording disc
Assignee: Fujifilm Holdings Corp
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Filing: 1979-09-14
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Granted: 1981-02-17
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Expires: 1999-09-14
Abstract
Abstract The inner surface of a disc jacket for retaining a magnetic recording disc is provided with a fibrous layer containing an antistatic agent. The fibrous layer is composed of a nonwoven cloth impregnated with the antistatic agent. The antistatic agent may be applied to the nonwoven cloth by spraying instead of impregnation.
Inventors
- 👤 Kenichi Masuyama
- 👤 Tatsuji Kitamoto
- 👤 Yasuyuki Yamada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:03
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/02; G11B23/03; G11B23/033; G11B23/0332; G11B23/50; G11B23/505
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
102 words
A disc jacket for a magnetic disc comprising a disc jacket and a flexible magnetic disc retained in the disc jacket, said disc jacket having openings for operating the magnetic disc from outside, wherein the improvement comprises a fibrous layer containing antistatic agents attached to the inner surface of the jacket, said antistatic agent being selected from the group consisting of anionic type antistatic agents having a composition formula of (C 18 H 35 OCO.COOH.H 2 NC 18 H 35 ), cationic type antistatic agents having a composition formula of ##STR11## and amphoteric type antistatic agents having a composition formula of ##STR12##
Claim 2
Dependent Claim
102 words
A disc jacket for a magnetic disc comprising a disc jacket and a flexible magnetic disc retained in the disc jacket, said disc jacket having openings for operating the magnetic disc from outside, wherein the improvement comprises a fibrous layer containing antistatic agents attached to the inner surface of the jacket, said antistatic agent being selected from the group consisting of anionic type antistatic agents having a composition formula of (C 18 H 35 OCO.COOH.H 2 NC 18 H 35 ), cationic type antistatic agents having a composition formula of ##STR11## and amphoteric type antistatic agents having a composition formula of ##STR12##
Claim 3
Dependent Claim
23 words
A disc jacket as claimed in claim 1 wherein said fibrous layer has a thickness of from about 20 to about 2,000 μm.
Claim 4
Dependent Claim
32 words
A disc jacket as claimed in claim 1 wherein about 1 to about 30 parts by weight of said antistatic agents are contained per 100 parts by weight of said fibrous layer.
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) | 1984-02-17 | 1984-08-18 | 1985-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-17 | 1988-08-18 | 1989-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-17 | 1992-08-18 | 1993-02-17 | $7700.00 | Window Closed / Lapsed |