US5000983A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of magnetic recording medium
Assignee: Fujifilm Corp
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Filing: 1988-12-16
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Granted: 1991-03-19
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Expires: 2008-12-16
Abstract
Abstract A process for the preparation of a magnetic recording medium which comprises the steps of subjecting a magnetic recording layer coated on a nonmagnetic support to surface smoothening treatment, said magnetic recording layer comprising a ferromagnetic powder dispersed in a binder which is composed of a resin component and a curing agent, and then shaving a surface of said magnetic recording layer by means of a shaving device having high hardness.
Inventors
- 👤 Shinobu Iida
- 👤 Masaaki Fujiyama
- 👤 Keisuke Yamada
- 👤 Hiroshi Kato
- 👤 Naoki Sakai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:54
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; Y; Y10; Y10S; Y10S428/00; Y10S428/90
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
153 words
A process for the preparation of a magnetic recording tape which comprises the steps of subjecting a magnetic recording layer coated on a non-magnetic support to surface smoothening treatment, said magnetic recording layer comprising a ferromagnetic powder dispersed in a binder which is composed of a resin component and a curing agent, and then shaving the surface of said magnetic recording layer by means of running the tape at a speed of 60-1,200 m/min., while contacting the surface with a sapphire blade at an angle between the rake face of the sapphire blade and the magnetic layer surface of 80°-120°, or while contacting with a diamond wheel having sintered diamond on its outer surface, and having thereon surface grits in the range of #1,200 to #5,000, wherein said diamond wheel rotates in the opposite direction against the running direction of the magnetic recording layer at a rotation speed of 300 to 6,000 rpm.
Claim 2
Dependent Claim
153 words
A process for the preparation of a magnetic recording tape which comprises the steps of subjecting a magnetic recording layer coated on a non-magnetic support to surface smoothening treatment, said magnetic recording layer comprising a ferromagnetic powder dispersed in a binder which is composed of a resin component and a curing agent, and then shaving the surface of said magnetic recording layer by means of running the tape at a speed of 60-1,200 m/min., while contacting the surface with a sapphire blade at an angle between the rake face of the sapphire blade and the magnetic layer surface of 80°-120°, or while contacting with a diamond wheel having sintered diamond on its outer surface, and having thereon surface grits in the range of #1,200 to #5,000, wherein said diamond wheel rotates in the opposite direction against the running direction of the magnetic recording layer at a rotation speed of 300 to 6,000 rpm.
Claim 3
Dependent Claim
33 words
The process as claimed in claim 1, wherein said binder is composed of a resin component containing a vinyl chloride copolymer and a polyurethane resin and a curing agent containing a polyisocyanate compound.
Claim 4
Dependent Claim
59 words
The process as claimed in claim 1, wherein said binder is composed of a resin component containing a vinyl chloride copolymer and a polyurethane resin and a curing agent containing a polyisocyanate compound and the ratio between the polyurethane resin and the polyisocyanate compound is in the range of from 1 : 0.8 to 1 : 2, by weight.
Claim 5
Dependent Claim
27 words
The process as claimed in claim 1, wherein the step of shaving is performed on a running magnetic recording layer under a tension of 30-100 g/8 mm.
References Cited (Backward Citations)
GB1397817A
Cited
US4557947A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-03-18 | 1994-09-17 | 1995-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-03-18 | 1998-09-17 | 1999-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-03-18 | 2002-09-17 | 2003-03-19 | $7700.00 | Window Closed / Lapsed |