US4828924A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording medium
Assignee: Maxell Ltd
•
Filing: 1987-10-30
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Granted: 1989-05-09
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Expires: 2007-10-30
Abstract
Abstract A magnetic recording medium of high durability comprising a substrate material and a magnetic layer provided on at least one surface of the substrate material, the magnetic layer comprising magnetic powder and a resinous binder, characterized in that the magnetic layer comprises further at least one compound of the formula: Rf--CH.sub.2 --R).sub.m X (I) wherein Rf is a fluorinated polyoxyalkyl group having 8 to 152 carbon atoms, R is an oxyalkylene group having 2 or 3 carbon atoms, X is a polar group such as --OH, --OCH 3 , -O-lower alkylene-COOH or -O-CO-lower alkylene-OH and m is an integer of not less than 1 uniformly and entirely dispersed in the magnetic layer.
Inventors
- 👤 Mitsutoshi Shoji
- 👤 Koo Honjoo
- 👤 Yoshiharu Honma
- 👤 Fumio Nakano
- 👤 Toshikazu Narahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:09
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; Y10T428/31504; Y10T428/3154; Y10T428/31544
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
143 words
A magnetic recording medium of high durability comprising a substrate material and a magnetic layer provided on at least one surface of said substrate material, said magnetic layer comprising magnetic powder and a resinous binder, characterized in that said magnetic layer comprises further at least one compound of the formula: Rf--CH.sub.2 --R).sub.m X (I) wherein Rf is a fluorinated polyoxyalkyl group having 8 to 152 carbon atoms, R is an oxyalkylene group having 2 or 3 carbon atoms, X is a polar group selected from the group consisting of --OH, --OCH 3 , --O-lower alkylene-COOH and --O-CO-lower alkylene-OH and m is an integer of not less than 1, uniformly and entirely dispersed in the magnetic layer, the amount of compound (I) in the magnetic layer ranging from about 0.1 to 20 parts by weight to 100 parts by weight of said magnetic powder.
Claim 2
Dependent Claim
143 words
A magnetic recording medium of high durability comprising a substrate material and a magnetic layer provided on at least one surface of said substrate material, said magnetic layer comprising magnetic powder and a resinous binder, characterized in that said magnetic layer comprises further at least one compound of the formula: Rf--CH.sub.2 --R).sub.m X (I) wherein Rf is a fluorinated polyoxyalkyl group having 8 to 152 carbon atoms, R is an oxyalkylene group having 2 or 3 carbon atoms, X is a polar group selected from the group consisting of --OH, --OCH 3 , --O-lower alkylene-COOH and --O-CO-lower alkylene-OH and m is an integer of not less than 1, uniformly and entirely dispersed in the magnetic layer, the amount of compound (I) in the magnetic layer ranging from about 0.1 to 20 parts by weight to 100 parts by weight of said magnetic powder.
Claim 3
Dependent Claim
36 words
The magnetic recording medium according to claim 1, wherein compound (I) is of the formula: ##STR30## wherein n is an integer of not less than 1, and m is an integer of not less than 1.
Claim 4
Dependent Claim
36 words
The magnetic recording medium according to claim 1, wherein compound (I) is of the formula: ##STR31## wherein n is an integer of not less than 1, and m is an integer of not less than 1.
Claim 5
Dependent Claim
35 words
The magnetic recording medium according to claim 1, wherein the amount compound (I) in the magnetic layer is from about 0.5 to 5 parts by weight to 100 parts by weight of the magnetic powder.
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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) | 1992-05-08 | 1992-11-07 | 1993-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-08 | 1996-11-07 | 1997-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-08 | 2000-11-07 | 2001-05-09 | $7700.00 | Window Closed / Lapsed |