Patent US320972A successfully refreshed from Google Patents.
US2883301A
Expired / Lapsed
US
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Magnetic recording tape
Assignee: Celanese Corp
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Filing: 1955-08-17
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Granted: 1959-04-21
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Expires: 1975-08-17
Abstract
No abstract record available.
Inventors
- 👤 John H Prichard
- 👤 Francis J Rielly
- 👤 Brown Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:00
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/739; G11B5/73923; G11B5/73937; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31971
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
67 words
PROCESS WHICH COMPRISES STRETCHING AT A TEMPERATURE OF 60 TO 100*C. FOR AN INCREASE IN DIMENSION ABOUT 15 TO 25% A FILM OF CELLULOSE ACETATE CONTAINING MINOR AMOUNT OF A PLASTICIZER THEREFOR, SAID CELLULOSE ACETATE HAVING A COMBINED ACETIC ACID CONTENT OF AT LEAST 60%, COOLING THE FILM IN STRETCHED CONDITION, AND THEN COATING THE FILM WITH A COMPOSITION COMPRISING A FERROMAGNETIC MATERIAL IN A BINDER THEREFOR.
Claim 2
Dependent Claim
67 words
PROCESS WHICH COMPRISES STRETCHING AT A TEMPERATURE OF 60 TO 100*C. FOR AN INCREASE IN DIMENSION ABOUT 15 TO 25% A FILM OF CELLULOSE ACETATE CONTAINING MINOR AMOUNT OF A PLASTICIZER THEREFOR, SAID CELLULOSE ACETATE HAVING A COMBINED ACETIC ACID CONTENT OF AT LEAST 60%, COOLING THE FILM IN STRETCHED CONDITION, AND THEN COATING THE FILM WITH A COMPOSITION COMPRISING A FERROMAGNETIC MATERIAL IN A BINDER THEREFOR.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-04-20 | 1962-10-20 | 1963-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-04-20 | 1966-10-20 | 1967-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-04-20 | 1970-10-20 | 1971-04-21 | $7700.00 | Window Closed / Lapsed |