US2553500A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of photographs in blue-black tones and compositions thereof
Assignee: GAF Chemicals Corp
•
Filing: 1946-08-01
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Granted: 1951-05-15
•
Expires: 1966-08-01
Abstract
No abstract record available.
Inventors
- 👤 Harold C Harsh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:29
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/305; Y; Y10; Y10S; Y10S430/00; Y10S430/166
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
66 words
THE PROCESS FOR PRODUCING DEVELOPED SILVER PICTURES IN BLUE-BLACK TONES WHICH COMPRISES DEVELOPING AN EXPOSED LIGHT-SENSITIVE SILVER-HALIDE EMULSION LAYER, WITH AN AQUEOUS SOLUTION OF AN ALKALINE PHOTOGRAPHIC DEVELOPER FOR SILVER HALIDE AMULSIONS COMPRISING AN AROMATIC SILVER HALIDE DEVELOPING AGENT, SAID SOLUTION CONTAINING FROM 20 TO 100 MGS. PER LITER OF SAID DEVELOPER A 1,34-TRIAZAINDOLIZINE SELECTED FROM THE CLASS CONSISTING OF THOSE CORRESPONDING TO THE GENERAL FORMULAE:
Claim 2
Dependent Claim
66 words
THE PROCESS FOR PRODUCING DEVELOPED SILVER PICTURES IN BLUE-BLACK TONES WHICH COMPRISES DEVELOPING AN EXPOSED LIGHT-SENSITIVE SILVER-HALIDE EMULSION LAYER, WITH AN AQUEOUS SOLUTION OF AN ALKALINE PHOTOGRAPHIC DEVELOPER FOR SILVER HALIDE AMULSIONS COMPRISING AN AROMATIC SILVER HALIDE DEVELOPING AGENT, SAID SOLUTION CONTAINING FROM 20 TO 100 MGS. PER LITER OF SAID DEVELOPER A 1,34-TRIAZAINDOLIZINE SELECTED FROM THE CLASS CONSISTING OF THOSE CORRESPONDING TO THE GENERAL FORMULAE:
References Cited (Backward Citations)
US1693500A
Cited
US2158184A
Cited
US2390707A
Cited
US2432419A
Cited
US2444607A
Cited
US2444606A
Cited
US2444605A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-05-14 | 1954-11-13 | 1955-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-05-14 | 1958-11-13 | 1959-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-05-14 | 1962-11-13 | 1963-05-15 | $7700.00 | Window Closed / Lapsed |