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Patent US2704710A successfully refreshed from Google Patents.
US2704710A
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Precipitation of azo dyes in silver halide emulsions by means of guanidine and biguanide compounds containing long alkyl chains
Assignee: GAF Chemicals Corp
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Filing: 1950-04-18
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Granted: 1955-03-22
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Expires: 1970-04-18
Abstract
No abstract record available.
Inventors
- 👤 Joseph A Sprung
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:15
CPC Classifications
C; C09; C09B; C09B69/00; C09B69/02; C09B69/04; C09B69/045; C07; C07C; C07C279/00; C07C279/20; C07C279/24; C07C279/26; G; G03; G03C; G03C7/00; G03C7/28
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
30 words
A PHOTOGRAPHIC SILVER HALIDE EMULSION CONTAINING AN AZO DYESTUFF RENDERED FAST TO DIFFUSION IN THE EMULSION BY THE ADDITION OF A SMALL QUANTITY OF A COMPOUND OF THE FOLLOWING FORMULA:
Claim 2
Dependent Claim
30 words
A PHOTOGRAPHIC SILVER HALIDE EMULSION CONTAINING AN AZO DYESTUFF RENDERED FAST TO DIFFUSION IN THE EMULSION BY THE ADDITION OF A SMALL QUANTITY OF A COMPOUND OF THE FOLLOWING FORMULA:
References Cited (Backward Citations)
US1954294A
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US2186849A
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US2268630A
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US2172308A
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US2368647A
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US2317184A
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US2294892A
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US2364374A
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US2545423A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-03-21 | 1958-09-20 | 1959-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-03-21 | 1962-09-20 | 1963-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-03-21 | 1966-09-20 | 1967-03-22 | $7700.00 | Window Closed / Lapsed |