US2850411A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for removing coatings from film base
Assignee: PAUL O TOBELER
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Filing: 1956-01-23
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Granted: 1958-09-02
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Expires: 1976-01-23
Abstract
No abstract record available.
Inventors
- 👤 Bratring Kurt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:12
CPC Classifications
C; C08; C08J; C08J11/00; C08J11/04; C08J11/06; C08J2301/00; C08J2301/08; C08J2301/16; C08J2301/18; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/62
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
102 words
THE METHOD OF TREATING PHOTOGRAPHIC FILM TO FREE ITS CELLULOID BASE OF SUPERPOSED ADHERENT COATINGS OF THE CLASS CONSISTING OF AT LEAST ONE PROTEIN CARRIER MATERIAL FOR A LIGHT SENSITIVE EMULSION AND A LACQUER COVER MATERIAL FOR SAID EMULSION, THAT INCLUDES CONTACTING THE FILM WITH A CONCENTRATED AQUEOUS SOLUTION OF ALKALINE MATERIAL SELECTED FROM THE GROUP CONSISTING OF CAUSTIC SODA AND CAUSTIC POTASH FOR A TIME INTERVAL SUFFICIENT TO DISSOLVE SAID COATINGS, SAID SOLUTION HAVING A CONCENTRATION OF BETWEEN 16 AND 50 PERCENT AND THEREAFTER WASHING THE FILM WITH A CELLULOID INACTIVE LIQUID TO REMOVE REMANENT CAUSTIC SOLUTION FROM THE FILM BASE.
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) | 1961-09-01 | 1962-03-03 | 1962-09-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-01 | 1966-03-03 | 1966-09-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-01 | 1970-03-03 | 1970-09-02 | $7700.00 | Window Closed / Lapsed |