Patent US4548873A successfully refreshed from Google Patents.
US4548873A
Expired / Lapsed
US
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Magnetic recording media with oxyfatty acid lubricant
Assignee: Fujifilm Holdings Corp
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Filing: 1983-10-03
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Granted: 1985-10-22
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Expires: 2003-10-03
Abstract
Abstract A magnetic recording medium is disclosed. The medium is comprised of a support and a magnetic layer provided thereon wherein an oxyfatty acid is incorporated in the magnetic layer or in the surface of a support or layer coming into contact with the magnetic layer. The coefficients of friction of the magnetic layer with parts of a magnetic recording/reproducing deck are low and thus the magnetic recording medium has superior lubricity.
Inventors
- 👤 Nobuyuki Yamamoto
- 👤 Yoshito Mukaida
- 👤 Nobuo Tsuji
- 👤 Yuzo Higaki
- 👤 Toshihisa Okamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:29
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/71; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
31 words
A magnetic recording medium, comprising: a support base having provided thereon a magnetic layer having a low coefficient of friction and improved lubricity; and 12-oxystearic acid contained within the magnetic layer.
Claim 2
Dependent Claim
31 words
A magnetic recording medium, comprising: a support base having provided thereon a magnetic layer having a low coefficient of friction and improved lubricity; and 12-oxystearic acid contained within the magnetic layer.
Claim 3
Dependent Claim
48 words
A magnetic recording medium as claimed in claim 1, wherein the magnetic layer is comprised of a ferromagnetic powder dispersed in a binder wherein the ferromagnetic powder is present in an amount of from 50 to 2,000 parts by weight per 100 parts by weight of the binder.
Claim 4
Dependent Claim
37 words
A magnetic recording medium as claimed in claim 2, wherein the 12-oxystearic acid is present in an amount in the range of 0.01 to 20 parts by weight per 100 parts by weight of the ferromagnetic powder.
Claim 5
Dependent Claim
38 words
A magnetic recording medium as claimed in claim 3, wherein the 12-oxystearic acid is present in an amount in the range of from 0.1 to 10 parts by weight per 100 parts by weight of the ferromagnetic powder.
Claim 6
Dependent Claim
38 words
A magnetic recording medium as claimed in claim 4, wherein the 12-oxystearic acid is present in an amount in the range of from 0.5 to 5 parts by weight per 100 parts by weight of the ferromagnetic powder.
Claim 7
Dependent Claim
39 words
A magnetic recording medium as claimed in claim 1, wherein the magnetic layer comprises a binder containing a dispersion of the ferromagnetic powder, and before the dispersion of the ferromagnetic powder in the binder, the 12-oxystearic acid is added.
Claim 8
Dependent Claim
32 words
A magnetic recording medium as claimed in claim 1, wherein the magnetic layer comprises a binder and after the dispersion of the ferromagnetic powder in the binder, the 12-oxystearic acid is added.
Claim 9
Dependent Claim
48 words
A magnetic recording medium as claimed in claim 1, wherein the magnetic layer is formed by forming a dispersion of the ferromagnetic powder, a binder and the 12-oxystearic acid in a solvent, whereafter the same is coated on the support base and dried to yield the magnetic layer.
Claim 10
Dependent Claim
31 words
A magnetic recording medium, comprising: a support base having provided thereon a magnetic layer having a low coefficient of friction and improved lubricity; and dioxypalmitic acid contained within the magnetic layer.
Claim 11
Dependent Claim
31 words
A magnetic recording medium, comprising: a support base having provided thereon a magnetic layer having a low coefficient of friction and improved lubricity; and dioxypalmitic acid contained within the magnetic layer.
Claim 12
Dependent Claim
48 words
A magnetic recording medium as claimed in claim 9, wherein the magnetic layer is comprised of a ferromagnetic powder dispersed in a binder wherein the ferromagnetic powder is present in an amount of from 50 to 2,000 parts by weight per 100 parts by weight of the binder.
Claim 13
Dependent Claim
37 words
A magnetic recording medium as claimed in claim 10, wherein the dioxypalmitic acid is present in an amount in the range of 0.01 to 20 parts by weight per 100 parts by weight of the ferromagnetic powder.
Claim 14
Dependent Claim
38 words
A magnetic recording medium as claimed in claim 11, wherein the dioxypalmitic acid is present in an amount in the range of form 0.1 to 10 parts by weight per 100 parts by weight of the ferromagnetic powder.
Claim 15
Dependent Claim
38 words
A magnetic recording medium as claimed in claim 12, wherein the dioxypalmitic acid is present in an amount in the range of from 0.5 to 5 parts by weight per 100 parts by weight of the ferromagnetic powder.
Claim 16
Dependent Claim
39 words
A magnetic recording medium as claimed in claim 9, wherein the magnetic layer comprises a binder containing a dispersion of the ferromagnetic powder, and before the dispersion of the ferromagnetic powder in the binder, the dioxypalmitic acid is added.
Claim 17
Dependent Claim
32 words
A magnetic recording medium as claimed in claim 9, wherein the magnetic layer comprises a binder and after the dispersion of the ferromagnetic powder in the binder, the dioxypalmitic acid is added.
Claim 18
Dependent Claim
48 words
A magnetic recording medium as claimed in claim 9, wherein the magnetic layer is formed by forming a dispersion of the ferromagnetic powder, a binder and the dioxypalmitic acid in a solvent, whereafter the same is coated on the support base and dried to yield the magnetic layer.
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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) | 1988-10-21 | 1989-04-22 | 1989-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-21 | 1993-04-22 | 1993-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-21 | 1997-04-22 | 1997-10-22 | $7700.00 | Window Closed / Lapsed |