US4587170A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording medium
Assignee: Fujifilm Holdings Corp
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Filing: 1984-06-28
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Granted: 1986-05-06
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Expires: 2004-06-28
Abstract
Abstract A magnetic recording medium comprising a nonmagnetic support having coated thereon a magnetic recording layer comprising a ferromagnetic particles dispersed in a binder, the binder containing polyisocyanate and the molar ratio of (urethane bond+allophanate bond):(urea bond+biuret bond) being 85:15 to 60:40.
Inventors
- 👤 Kazuko Hanai
- 👤 Takashi Yoneyama
- 👤 Toshihisa Ito
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:53
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; G11B5/7021; C; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/77; C08G18/78; C08G18/7806; C08G18/7818; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/25; Y10T428/256; Y10T428/257; Y10T428/31504; Y10T428/31551; Y10T428/31609; Y10T428/31855; Y10T428/31935; Y10T428/31971
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
61 words
A wear resistant magnetic recording medium comprising a non-magnetic support having coated thereon a magnetic recording layer comprising ferromagnetic particles dispersed in a binder, the binder containing polyisocyanate and polyurethane and the molar ratio of (urethane bond+allophanate bond):(urea bond+biuret bond) being 85:15 to 60:40, wherein the main component of the binder is a vinyl chloride copolymer, nitrocellulose or a mixture thereof.
Claim 2
Dependent Claim
61 words
A wear resistant magnetic recording medium comprising a non-magnetic support having coated thereon a magnetic recording layer comprising ferromagnetic particles dispersed in a binder, the binder containing polyisocyanate and polyurethane and the molar ratio of (urethane bond+allophanate bond):(urea bond+biuret bond) being 85:15 to 60:40, wherein the main component of the binder is a vinyl chloride copolymer, nitrocellulose or a mixture thereof.
Claim 3
Dependent Claim
21 words
The magnetic recording medium of claim 1, wherein said molar ratio of (urethane bond+allophane bond):(urea bond+biuret bond) is 80:20 to 70:30.
Claim 4
Dependent Claim
18 words
The magnetic recording medium of claim 1, wherein the residual isocyanate content is not more than about 10%.
Claim 5
Dependent Claim
51 words
The magnetic recording medium of claim 1, wherein said binder comprises 15 to 60% by weight of said vinyl chloride copolymer, nitrocelluose or a mixture thereof, 20 to 60% by weight of a polyurethane and 5 to 90% by weight of a polyisocyante based on the total weight of the binder.
Claim 6
Dependent Claim
51 words
The magnetic recording medium of claim 1, wherein said binder comprises 20 to 60% by weight of said vinyl chloride copolymer, nitrocelluose or a mixture thereof, 20 to 60% by weight of a polyurethane and 10 to 60% by weight of a polyisocyanate based on the total weight of the binder.
Claim 7
Dependent Claim
17 words
The magnetic recording medium of claim 1, wherein the main binder component is a vinyl chloride copolymer.
Claim 8
Dependent Claim
14 words
The magnetic recording medium of claim 1, wherein the main binder component is nitrocellulose.
Claim 9
Dependent Claim
22 words
The magnetic recording medium of claim 1, wherein the main binder component is a mixture of a vinyl chloride copolymer and nitrocellulose.
References Cited (Backward Citations)
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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) | 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 |