Patent US4395466A successfully refreshed from Google Patents.
US4395466A
Expired / Lapsed
US
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Magnetic recording medium
Assignee: Fujifilm Holdings Corp
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Filing: 1981-05-20
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Granted: 1983-07-26
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Expires: 2001-05-20
Abstract
Abstract A magnetic recording medium comprising a non-magnetic base which has formed thereon a magnetic layer made of a binder and fine ferromagnetic particles dispersed therein is disclosed. The magnetic layer is characterized by containing a mineral oil having a viscosity of 300 cs or less at 37.8° C. and an aliphatic acid having 12 to 22 carbon atoms.
Inventors
- 👤 Hiroshi Ogawa
- 👤 Yasuo Tamai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:02
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/71; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/25
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
97 words
A magnetic recording medium, comprising: a non-magnetic base; a magnetic layer formed on said base; said magnetic layer consisting essentially of a binder and fine ferromagnetic particles dispersed within said binder, a mineral oil having a viscosity of 300 cs or less at 37.8° C. contained in said magnetic layer an an amount of 0.05 weight percent to 1 weight percent, and an aliphatic acid having 12 to 22 carbon atoms contained in said magnetic layer in an amount of about 0.2 weight percent to 5.0 weight percent, based on the weight of the fine ferromagnetic powder.
Claim 2
Dependent Claim
97 words
A magnetic recording medium, comprising: a non-magnetic base; a magnetic layer formed on said base; said magnetic layer consisting essentially of a binder and fine ferromagnetic particles dispersed within said binder, a mineral oil having a viscosity of 300 cs or less at 37.8° C. contained in said magnetic layer an an amount of 0.05 weight percent to 1 weight percent, and an aliphatic acid having 12 to 22 carbon atoms contained in said magnetic layer in an amount of about 0.2 weight percent to 5.0 weight percent, based on the weight of the fine ferromagnetic powder.
Claim 3
Dependent Claim
62 words
A magnetic recording medium as claimed in claim 1 wherein said mineral oil is contained in said magnetic layer in an amount of between 0.1 weight percent to 1.0 weight percent based on the weight of the fine ferromagnetic powder, and said aliphatic acid is contained within said magnetic layer in an amount of between 0.5 weight percent to 3.0 weight percent.
Claim 4
Dependent Claim
17 words
A magnetic recording medium as claimed in claim 1, further comprising a dispersant, an abrasive, and carbon.
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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) | 1986-07-25 | 1987-01-24 | 1987-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-25 | 1991-01-24 | 1991-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-25 | 1995-01-24 | 1995-07-26 | $7700.00 | Window Closed / Lapsed |