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US4709816A Expired / Lapsed US ⏱️ 0.0 years remaining

Recording disc cartridge

Assignee: Maxell Ltd
•
Filing: 1986-03-11
•
Granted: 1987-12-01
•
Expires: 2006-03-11
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Abstract

Abstract A recording disc cartridge comprising a recording disc containing, at least in its surface layer, at least one compound selected from the group consisting of an aliphatic acid and its salt and derivative, a case in which the recording disc is rotatively contained, and a liner comprising polyester fiber which is interposed between the case and the recording disc with facing the disc, which has good durability and less drop out.

Inventors

  • 👤 Fujio Matsumoto
  • 👤 Hajime Doi
  • 👤 Kunio Mizushima
  • 👤 Masaya Funahashi
  • 👤 Tomizo Taniguchi
  • 👤 Shoichi Sakamoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 02:20
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/02; G11B23/03; G11B23/033; G11B23/0332; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/1362; Y10T428/23; Y10T428/237

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 70 words
A recording disc cartridge comprising a recording disc containing, at least in its surface layer, a lubricant comprising at least one compound selected from the group consisting of an aliphatic acid, its salt, ester and amide, a case in which the recording disc is rotatively contained, and a liner comprising at least 30% by weight polyester fiber which is interposed between the case and the recording disc, facing the disc.
Claim 2
Dependent Claim 70 words
A recording disc cartridge comprising a recording disc containing, at least in its surface layer, a lubricant comprising at least one compound selected from the group consisting of an aliphatic acid, its salt, ester and amide, a case in which the recording disc is rotatively contained, and a liner comprising at least 30% by weight polyester fiber which is interposed between the case and the recording disc, facing the disc.
Claim 3
Dependent Claim 20 words
The recording disc cartridge according to claim 1, wherein said liner comprises 40 to 90% by weight of polyester fiber.
Claim 4
Dependent Claim 22 words
The recording disc cartridge according to claim 1, wherein said liner comprises a non-woven mixed fabric of polyester fiber and rayon fiber.
Claim 5
Dependent Claim 33 words
The recording disc cartridge according to claim 1, wherein said recording disc comprises a magnetic surface layer which contains a magnetic powder and an ester of an unsaturated aliphatic acid as said lubricant.
Claim 6
Dependent Claim 40 words
The recording disc cartridge according to claim 4, wherein the amount of lubricant contained in said magnetic layer is from 1.0 to 40.0 parts by weight per 100 parts by weight of said magnetic powder contained in said magnetic layer.
Claim 7
Dependent Claim 20 words
The recording disc cartridge according to claim 4, wherein a thickness of said magnetic layer is 0.5 to 2.0 μm.
Claim 8
Dependent Claim 33 words
The recording disc cartridge according to claim 3, wherein said recording disc is a magnetic disc comprising a magnetic surface layer which contains an ester of an unsaturated aliphatic acid as said lubricant.
Claim 9
Dependent Claim 45 words
The recording disc cartridge according to claim 7, wherein said ester is at least one ester of an unsaturated aliphatic acid selected from the group consisting of oleic acid, linolic acid and linoleic acid with an aliphatic alcohol having from 8 to 18 carbon atoms.

References Cited (Backward Citations)

US4135016A Cited
US4251843A Cited
US4223361A Cited
US4420532A Cited
US4414597A Cited
US4579778A Cited
US4610352A Cited
US4485421A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-11-30 1991-06-01 1991-12-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-11-30 1995-06-01 1995-12-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-11-30 1999-06-01 1999-12-01 $7700.00 Window Closed / Lapsed

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