Patent US743373A successfully refreshed from Google Patents.
Patent US2989415A successfully refreshed from Google Patents.
US2989415A
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Magnetic recording medium and method of making the same
Assignee: International Business Machines Corp
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Filing: 1957-12-19
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Granted: 1961-06-20
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Expires: 1977-12-19
Abstract
No abstract record available.
Inventors
- 👤 Paul V Horton
- 👤 Robert S Haines
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:12
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/702; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31678; Y10T428/31681; Y10T428/31786; Y10T428/31797
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
123 words
THE METHOD OF PREPARING A MAGNETIC RECORDING MEDIUM COMPRISING THE STEPS OF PREPARING A BLEND OF ABOUT 90-30 PARTS BY WEIGHT OF AN UNCURED ELASTOMERIC COPOLYMER AND ABOUT 10-70 PARTS BY WEIGHT OF AN UNCURED THERMOSETTING RESINOUS CONDENSATE OF AN ALDEHYDE AND A PHENOL SAID ELASTOMERIC COPOLYMER HAVING BEEN FORMED FROM ABOUT 55-85 PARTS BY WEIGHT OF BUTADIENE AND ABOUT 45-15 PARTS OF ACRYLONITRILE, PREPARING A SOLUTION OF SAID BINDER IN AN ORGANIC SOLVENT, INCORPORATING IN SAID SOLUTION FINELY DIVIDED MAGNETIC PARTICLES TO FORM A DISPERSION, APPLYING A LAYER OF SAID DISPERSION TO A THIN FLEXIBLE NONMAGNETIC BACKING, REMOVING SAID SOLVENT FROM SAID DISPERSION, AND CURING SAID BINDER TO PRODUCE A FIRMLY ADHERING ABRASION RESISTANT LAYER OF BONDED MAGNETIC PARTICLES ON SAID BACKING.
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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) | 1964-06-19 | 1964-12-19 | 1965-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-19 | 1968-12-19 | 1969-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-19 | 1972-12-19 | 1973-06-20 | $7700.00 | Window Closed / Lapsed |