US4363869A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photographic developing process
Assignee: Individual
•
Filing: 1981-10-19
•
Granted: 1982-12-14
•
Expires: 2001-10-19
Abstract
Abstract A two-component system for developing photosensitive materials provides a developing process which is not highly dependent upon critical values of time and temperature. The resultant developed materials possess less graininess than might be expected with conventional developer systems. The two-composition system is comprised of a first and a second composition employed as aqueous solutions, each containing an alkali sulfite. The first compositon comprises a phenylamine developer compound and hydroquinone.
Inventors
- 👤 Robert E. Hutchinson, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 09:54
CPC Classifications
G; G06; G06T; G06T3/00; G06T3/40; G03; G03C; G03C5/00; G03C5/26
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
152 words
A process for the development of photographic material initially containing silver halide to produce a silver image, said photographic material having been imagewise exposed to radiation, said process comprising: (a) uniformly treating said photographic material with a first aqueous solution having a pH between 7.5 and 12 and comprising ______________________________________
Component Weight Ratio
______________________________________
N--methyl-p-aminophenol sulfate
1.9-2.1
sodium sulfite 46-54
hydroquinone 4-8
______________________________________ said first solution containing between about 56 and 60 grams of said components per quart, (b) separating said photographic material from said first solution, (c) treating said photographic material uniformly with a second aqueous solution having a pH between 7.5 and 12 and comprising ______________________________________
Component Weight Ratio
______________________________________
borax 40-60
sodium sulfite 90-110
______________________________________ said second solution containing between about 130 and 170 grams of said components per quart, (d) separating said photographic material from said second solution, (e) fixing, (f) washing, and (g) drying said photographic material.
Claim 2
Dependent Claim
152 words
A process for the development of photographic material initially containing silver halide to produce a silver image, said photographic material having been imagewise exposed to radiation, said process comprising: (a) uniformly treating said photographic material with a first aqueous solution having a pH between 7.5 and 12 and comprising ______________________________________
Component Weight Ratio
______________________________________
N--methyl-p-aminophenol sulfate
1.9-2.1
sodium sulfite 46-54
hydroquinone 4-8
______________________________________ said first solution containing between about 56 and 60 grams of said components per quart, (b) separating said photographic material from said first solution, (c) treating said photographic material uniformly with a second aqueous solution having a pH between 7.5 and 12 and comprising ______________________________________
Component Weight Ratio
______________________________________
borax 40-60
sodium sulfite 90-110
______________________________________ said second solution containing between about 130 and 170 grams of said components per quart, (d) separating said photographic material from said second solution, (e) fixing, (f) washing, and (g) drying said photographic material.
References Cited (Backward Citations)
US1984086A
Cited
US2178896A
Cited
US2662014A
Cited
US2819165A
Cited
US2885288A
Cited
US3265501A
Cited
US3161513A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-12-13 | 1986-06-14 | 1986-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-12-13 | 1990-06-14 | 1990-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-12-13 | 1994-06-14 | 1994-12-14 | $7700.00 | Window Closed / Lapsed |