US4348475A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of photographic images
Assignee: Agfa Gevaert AG
•
Filing: 1980-04-23
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Granted: 1982-09-07
•
Expires: 2000-04-23
Abstract
Abstract In a process for the production of photographic images exposed photographic materials are treated with a developer having an enhanced bromide ion concentration which is kept constant for the duration of the use of the developer. The advantage of the process is based on the technically uncomplicated regenerability of the developer.
Inventors
- 👤 Ubbo Wernicke
- 👤 Heinz Meckl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 04:22
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/44
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
93 words
A photographic development process which comprises processing exposed multi-layer color photographic material under development conditions to produce images of maximum density with a color developer composition having an effective bromide ion concentration equivalent to at least in excess of ten grams of potassium bromide per liter of color developer including the step of maintaining the said bromide ion concentration in said developer at a substantial constant by removing bromide ion from the developer by contacting the developer with a strongly basic ion exchange resin based on styrene-divinyl benzene and thereby removing bromide ions.
Claim 2
Dependent Claim
93 words
A photographic development process which comprises processing exposed multi-layer color photographic material under development conditions to produce images of maximum density with a color developer composition having an effective bromide ion concentration equivalent to at least in excess of ten grams of potassium bromide per liter of color developer including the step of maintaining the said bromide ion concentration in said developer at a substantial constant by removing bromide ion from the developer by contacting the developer with a strongly basic ion exchange resin based on styrene-divinyl benzene and thereby removing bromide ions.
References Cited (Backward Citations)
US2073621A
Cited
GB709179A
Cited
US3253920A
Cited
US3627530A
Cited
US4163023A
Cited
US4159245A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-09-06 | 1986-03-08 | 1986-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-06 | 1990-03-08 | 1990-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-06 | 1994-03-08 | 1994-09-07 | $7700.00 | Window Closed / Lapsed |