US2525753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gelatin derivatives
Assignee: Eastman Kodak Co
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Filing: 1947-08-13
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Granted: 1950-10-10
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Expires: 1967-08-13
Abstract
No abstract record available.
Inventors
- 👤 Henry C Yutzy
- 👤 Gordon F Frame
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:47
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/04; G03C1/047
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
71 words
THE METHOD OF PREPARING A GELATING DERIVATIVE WHICH COMPRISES REACTING GELATIN WITH A DICARBOXYLIC ACID ANHYDRIDE SELECTED FROM THE GROUP CONSISTING OF PHTHALIC, SUCCINIC, MALEIC AND THE CHLORO-, BROMO- AND SULFO-SUBSTITUTED ANHYDRIDES CORRESPONDING THERETO IN AN AQUEOUS SYSTEM IN WHICH THE PH IS MAINTAINED AT BETWEEN 7 AND 12 AT A TEMPERATURE OF 30-70*C. FOR A NON-DEGRADING TIME OF NOT MORE THAN FORTY MINUTES AFTER THE ANHYDRIDE HAS BEEN COMPLETELY ADDED.
Claim 2
Independent Claim
71 words
THE METHOD OF PREPARING A GELATING DERIVATIVE WHICH COMPRISES REACTING GELATIN WITH A DICARBOXYLIC ACID ANHYDRIDE SELECTED FROM THE GROUP CONSISTING OF PHTHALIC, SUCCINIC, MALEIC AND THE CHLORO-, BROMO- AND SULFO-SUBSTITUTED ANHYDRIDES CORRESPONDING THERETO IN AN AQUEOUS SYSTEM IN WHICH THE PH IS MAINTAINED AT BETWEEN 7 AND 12 AT A TEMPERATURE OF 30-70*C. FOR A NON-DEGRADING TIME OF NOT MORE THAN FORTY MINUTES AFTER THE ANHYDRIDE HAS BEEN COMPLETELY ADDED.
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) | 1953-10-09 | 1954-04-10 | 1954-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-10-09 | 1958-04-10 | 1958-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-10-09 | 1962-04-10 | 1962-10-10 | $7700.00 | Window Closed / Lapsed |