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US4587150A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic recording medium

Assignee: TDK Corp
•
Filing: 1984-08-01
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Granted: 1986-05-06
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Expires: 2004-08-01
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Abstract

Abstract A magnetic recording medium comprising a plastic base film, a thin magnetic metal layer formed on one side of the base film and a backing layer formed on the other side of the base film, characterized in that the backing layer is composed essentially of a thermoset or radiation-cured resin and carbon black dispersed in the resin, and has a surface roughness of from 0.05 to 0.4 μm, said carbon black having an average particle size of from 10 to 60 mμm as measured by an electron microscope.

Inventors

  • 👤 Masaharu Nishimatsu
  • 👤 Toshiaki Ide
  • 👤 Hiroyuki Arioka
  • 👤 Yuichi Kubota

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 21:29
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/735; G11B5/7356; G11B5/7358; G11B5/739; G11B5/73923; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/24; Y10T428/24355; Y10T428/24372; Y10T428/25; Y10T428/30

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 88 words
A magnetic recording medium comprising a plastic base film, a thin magnetic metal layer formed on one side of the base film and a backing layer formed on the other side of the base film, characterized in that the backing layer is composed essentially of a thermoset or radiation-cured resin and carbon black dispersed in the resin, and has a surface roughness of from 0.05 to 0.4 μm, said carbon black having an average particle size of from 10 to 60 mμm as measured by an electron microscope.
Claim 2
Dependent Claim 88 words
A magnetic recording medium comprising a plastic base film, a thin magnetic metal layer formed on one side of the base film and a backing layer formed on the other side of the base film, characterized in that the backing layer is composed essentially of a thermoset or radiation-cured resin and carbon black dispersed in the resin, and has a surface roughness of from 0.05 to 0.4 μm, said carbon black having an average particle size of from 10 to 60 mμm as measured by an electron microscope.
Claim 3
Dependent Claim 31 words
The magnetic recording medium according to claim 1, wherein the thermoset resin is made of a thermosetting binder comprising a vinyl chloride-vinyl acetate-vinyl alcohol copolymer, a polyurethane prepolymer and a polyisocyanate.
Claim 4
Dependent Claim 15 words
The magnetic recording medium according to claim 2, wherein the thermosetting binder further contains nitrocellulose.
Claim 5
Dependent Claim 26 words
The magnetic recording medium according to claim 1, wherein the radiation-cured resin is made of a radiation curable binder composed essentially of a radiation sensitive resin.
Claim 6
Dependent Claim 22 words
The magnetic recording medium according to claim 4, wherein the radiation sensitive resin has radiation curable acrylic, maleic or allyl-type double bonds.

References Cited (Backward Citations)

US4328935A Cited
US4443514A Cited
US4419406A Cited
US4451531A Cited
US4452863A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1989-05-05 1989-11-04 1990-05-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1993-05-05 1993-11-04 1994-05-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1997-05-05 1997-11-04 1998-05-06 $7700.00 Window Closed / Lapsed

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