US2656271A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of developing aged photosensitive material containing silver halide and a chromate
Assignee: Keuffel and Esser Co
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Filing: 1950-10-13
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Granted: 1953-10-20
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Expires: 1970-10-13
Abstract
No abstract record available.
Inventors
- 👤 Neugebauer Wilhelm
- 👤 Reichel Maximilian Karl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:47
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/76; G03C1/77; G03C5/00; G03C5/26; G03C5/29; G03C5/305; G03C5/40
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
81 words
THE METHOD OF PRODUCING IMAGES RICH IN CONTRAST FROM AGED PHOTOSENSITIVE MATERIAL COMPRISING A COLLOID LAYER CONTAINING SILVER HALIDE AND A CHROMATE ON A BASE, WHICH COMPRISES TREATING SAID MATERIAL AFTER ITS EXPOSURE TO LIGHT UNDER A MASTER WITH A DEVELOPING SOLUTION CONTAINING A REDUCING AGENT FOR THE EXPOSED SILVER HALIDE AND A MONO-NITRO-SUBSTITUTED HETEROCYCLIC COMPOUND SELECTED FROM THE GROUP OF NITRO SUBSTITUTED BENZENE AND NITRO SUBSTITUTED NAPHTHALENE CONDENSED WITH A FIVE-MEMBERED CLOSED HETEROCYCLIC CHAIN SELECTED FROM THE GROUP CONSISTING OF
Claim 2
Independent Claim
81 words
THE METHOD OF PRODUCING IMAGES RICH IN CONTRAST FROM AGED PHOTOSENSITIVE MATERIAL COMPRISING A COLLOID LAYER CONTAINING SILVER HALIDE AND A CHROMATE ON A BASE, WHICH COMPRISES TREATING SAID MATERIAL AFTER ITS EXPOSURE TO LIGHT UNDER A MASTER WITH A DEVELOPING SOLUTION CONTAINING A REDUCING AGENT FOR THE EXPOSED SILVER HALIDE AND A MONO-NITRO-SUBSTITUTED HETEROCYCLIC COMPOUND SELECTED FROM THE GROUP OF NITRO SUBSTITUTED BENZENE AND NITRO SUBSTITUTED NAPHTHALENE CONDENSED WITH A FIVE-MEMBERED CLOSED HETEROCYCLIC CHAIN SELECTED FROM THE GROUP CONSISTING OF
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) | 1956-10-19 | 1957-04-20 | 1957-10-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-10-19 | 1961-04-20 | 1961-10-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-10-19 | 1965-04-20 | 1965-10-20 | $7700.00 | Window Closed / Lapsed |