US3632373A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for preparing silver halide layers having substantially uniform image contrast
Assignee: Eastman Kodak Co
•
Filing: 1968-04-01
•
Granted: 1972-01-04
•
Expires: 1988-04-01
Abstract
Abstract Photographic elements are provided which comprise a support having thereon a layer containing silver halide and a photographic image forming coupler, the ratio of coupler to the silver halide varying from area-to-area in the layer, the layer also including a development inhibitor-releasing coupler which is maintained at a constant ratio to the image-forming coupler in all areas of the layer. The development inhibitor-releasing coupler functions to reduce variations in dye image contrast caused by the varying ratio of photographic image-forming coupler to silver halide in the layer. Methods for preparing photographic elements are also provided.
Inventors
- 👤 Reid J O'connell
- 👤 John H Van Campen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:08
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/32; G03C7/3225
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
54 words
The method of claim 1 wherein said photographic image-forming coupler, upon reaction with oxidized primary aromatic amine color developing agent, forms nondiffusible image dye; and, said development inhibitor-releasing coupler has a monothio group in its coupling position which, upon reaction with oxidized primary aromatic amine color-developing agent, forms a diffusible mercaptan which inhibits development.
Claim 2
Dependent Claim
31 words
The method of claim 1 wherein each of said couplers are selected from the group consisting of an open-chain ketomethylene coupler radical; a 5-pyrazolone coupler radical; and, a phenolic coupler radical.
Claim 3
Dependent Claim
18 words
The method of in claim 3 wherein each of said couplers has one of the following structural formulas:
Claim 4
Dependent Claim
17 words
The method of claim 3 wherein each of said couplers has one of the following structural formulas:
Claim 5
Dependent Claim
31 words
The method of claim 5 wherein said Y1, Y2 and Y3 each represents a heterocyclic monothio radical containing from one to four hetero nitrogen atoms, to complete said development inhibitor-releasing coupler.
Claim 6
Dependent Claim
43 words
The method of claim 6 wherein said Y1, Y2 and Y3 each represents a member selected from the group consisting of: a 2-nitrophenylthio group; a 2-aminophenylthio group; a 5-tetrazolylthio group; a 2-benzothiazolylthio group; and a 5-phenyl-1,3,4-oxadiazolylthio group, to complete said development inhibitor-releasing coupler.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-03 | 1975-07-05 | 1976-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-03 | 1979-07-05 | 1980-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-03 | 1983-07-05 | 1984-01-04 | $7700.00 | Window Closed / Lapsed |