Patent US3257205A successfully refreshed from Google Patents.
US3257205A
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Method for heat development
Assignee: Gevaert Photo Producten NV
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Filing: 1961-10-10
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Granted: 1966-06-21
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Expires: 1981-10-10
Abstract
No abstract record available.
Inventors
- 👤 Cassiers Paul Maria
- 👤 Haes Louis Maria De
- 👤 Vanreusel Gerard Laurens
- 👤 Willems Josef Frans
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:26
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/42; G03C11/00; G03C11/08; G03C8/00; G03C8/40
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
50 words
A PROCESS FOR THE PRODUCTION OF PHOTOGRAPHIC COPIES BY HEAT DEVELOPMENT WHICH COMPRISES THE STEPS OF: (1) EXPOSING TO THE OBJECT TO BE COPIED A PHOTOGRAPHIC MATERIAL COMPRISING A SILVER HALIDE EMULSION LAYER AND CONTAINING A COMPOUND LIBERATING MOISTURE ON HEATING AND A 3-PYRAZOLIDONE DEVELOPING COMPOUND OF THE GENERAL FORMULA:
Claim 2
Dependent Claim
50 words
A PROCESS FOR THE PRODUCTION OF PHOTOGRAPHIC COPIES BY HEAT DEVELOPMENT WHICH COMPRISES THE STEPS OF: (1) EXPOSING TO THE OBJECT TO BE COPIED A PHOTOGRAPHIC MATERIAL COMPRISING A SILVER HALIDE EMULSION LAYER AND CONTAINING A COMPOUND LIBERATING MOISTURE ON HEATING AND A 3-PYRAZOLIDONE DEVELOPING COMPOUND OF THE GENERAL FORMULA:
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-06-20 | 1969-12-20 | 1970-06-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-06-20 | 1973-12-20 | 1974-06-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-06-20 | 1977-12-20 | 1978-06-21 | $7700.00 | Window Closed / Lapsed |