US3265499A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photographic developing compositions
Assignee: Gevaert Photo Producten NV
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Filing: 1962-07-09
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Granted: 1966-08-09
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Expires: 1982-07-09
Abstract
No abstract record available.
Inventors
- 👤 Willems Jozef Frans
- 👤 Georges Frans Van Veelen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:59
CPC Classifications
C; C07; C07D; C07D295/00; C07D295/04; C07D295/08; C07D295/096; C07D215/00; C07D215/02; C07D215/16; C07D215/20; G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/30; G03C5/3021; G03C8/00; G03C8/02; G03C8/04; G03C8/06
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
76 words
IN A PHOTOGRAPHIC COPYING METHOD OF THE DIFFUSION TRANSFER TYPE WHICH INCLUDES THE STEPS OF IMAGE-WISE EXPOSING A SUPPORTED SILVER HALIDE EMULSION LAYER, AND DEVELOPING SAID EXPOSED LAYER WHILE IN INTIMATE CONTACT WITH A SUPPORTED RECEIVING LAYER PROVIDING DEVELOPMENT NUCLEI, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT SAID DEVELOPING STEP IN THE PRESENCE OF A SUPER ADDITIVE COMBINATION OF DEVELOPING AGENTS COMPRISED ESSENTIALLY OF HYDROQUINONE AND A DERIVATIVE OF P-AMINOPHENOL HAVING ONE OF THE FOLLOWING GENERAL FORMULAE:
References Cited (Backward Citations)
US3072480A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-08-08 | 1970-02-07 | 1970-08-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-08-08 | 1974-02-07 | 1974-08-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-08-08 | 1978-02-07 | 1978-08-09 | $7700.00 | Window Closed / Lapsed |