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US4315052A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic recording medium

Assignee: Victor Company of Japan Ltd
•
Filing: 1980-06-23
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Granted: 1982-02-09
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Expires: 2000-06-23
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Abstract

Abstract A magnetic recording medium which comprises a support, and a magnetic recording layer formed on the support, the magnetic recording layer being comprised of a major proportion of a magnetic metal powder and minor proportions of a metal oxide powder, the metal oxide powder serving as a wear-resistant agent, an organic binder and ethylene stearyl bisamide serving as a lubricant.

Inventors

  • 👤 Noboru Takahashi
  • 👤 Sadao Ozaki
  • 👤 Hiromasa Isono
  • 👤 Toshikazu Nishihara
  • 👤 Takeshi Ikushima
  • 👤 Tunehide Naruse

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 07:33
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/706; G11B5/70605; G11B5/70615; G11B5/702; G11B5/7028; G11B5/70621; G11B5/708; G11B5/7085; G11B5/71; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/25; Y10T428/256

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 67 words
A magnetic recording medium comprising a suport and a magnetic recording layer formed on said support and comprised of a magnetic powder of a metal or alloy, about 2.0 to 20 wt % of an abrasion-resistant metal oxide, about 1.0 to 10 wt % of ethylene stearyl bisamide and about 10 to 25 wt % of an organic resin binder, all based on said magnetic metal powder.
Claim 2
Dependent Claim 67 words
A magnetic recording medium comprising a suport and a magnetic recording layer formed on said support and comprised of a magnetic powder of a metal or alloy, about 2.0 to 20 wt % of an abrasion-resistant metal oxide, about 1.0 to 10 wt % of ethylene stearyl bisamide and about 10 to 25 wt % of an organic resin binder, all based on said magnetic metal powder.
Claim 3
Dependent Claim 29 words
A magnetic recording medium according to claim 1, wherein said ethylene stearyl bisamide is contained in an amount of about 1 to 5 wt % of said metal powder.
Claim 4
Dependent Claim 27 words
A magnetic recording medium according to claim 2, wherein said wear-resistant metal oxide is Al 2 O 3 , Cr 2 O 3 or a mixture thereof.
Claim 5
Dependent Claim 31 words
A magnetic recording medium according to claim 1, wherein said magnetic metal powder is an acicular magnetic powder of iron or iron-cobalt alloys having a mean length of 0.3 to 0.6μ.

References Cited (Backward Citations)

GB820931A Cited
GB1049628A Cited
US3387993A Cited
US3843404A Cited
US4074012A Cited
US4074002A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-02-08 1985-08-10 1986-02-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-02-08 1989-08-10 1990-02-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-02-08 1993-08-10 1994-02-09 $7700.00 Window Closed / Lapsed

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