US4212936A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Color contrast radiographic film
Assignee: 3M Co
•
Filing: 1977-11-25
•
Granted: 1980-07-15
•
Expires: 1997-11-25
Abstract
Abstract A photographic element having at least two silver halide emulsion layers, one layer containing a colorless cyan-forming coupler which produces a negative image and the other layer containing a colored coupler which upon color development with a p-phenylene diamine developer produces a positive dye image of contrasting color to cyan, will produce a color contrast radiographic picture after exposure and development.
Inventors
- 👤 Claudio Giampieri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:48
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/16; Y; Y10; Y10S; Y10S430/00; Y10S430/167; Y10S430/168
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
122 words
A photographic element for use in radiography which includes a base and, on one side of said base, only two silver halide emulsion layers, said element characterized by the fact that (1) said two silver halide emulsion layers in the element may contain as couplers only colorless cyan forming couplers and yellow colored couplers; (2) at least one of said emulsion layers is reactively associated with said colorless cyan forming coupler so as to give a negative colored cyan image upon color development with p-phenylene diamine, (3) the other of said emulsion layers is reactively associated with said yellow colored coupler so as to leave a yellow colored positive image and a magenta colored negative image upon color development with p-phenylene diamine.
Claim 2
Dependent Claim
122 words
A photographic element for use in radiography which includes a base and, on one side of said base, only two silver halide emulsion layers, said element characterized by the fact that (1) said two silver halide emulsion layers in the element may contain as couplers only colorless cyan forming couplers and yellow colored couplers; (2) at least one of said emulsion layers is reactively associated with said colorless cyan forming coupler so as to give a negative colored cyan image upon color development with p-phenylene diamine, (3) the other of said emulsion layers is reactively associated with said yellow colored coupler so as to leave a yellow colored positive image and a magenta colored negative image upon color development with p-phenylene diamine.
Claim 3
Dependent Claim
18 words
The element of claim 1 wherein said two emulsion layers are sensitized with blue or green sensitizing dyes.
Claim 4
Dependent Claim
31 words
Photographic element of claim 1 characterized by having the emulsion layer associated with the colored coupler directly coated on the base and the emulsion associated with the colorless coupler coated thereon.
Claim 5
Dependent Claim
26 words
Photographic element of claim 1 characterized by having coated on the other side of the base an emulsion layer associated with a cyan forming colorless coupler.
Claim 6
Dependent Claim
25 words
Photographic element of claim 4 characterized by having coated between the base and the cyan-colorless-coupler-containing emulsion an emulsion layer associated with said yellow colored coupler.
Claim 7
Dependent Claim
37 words
Photographic element of claim 1 characterized by the fact that the sensitivity of the emulsion associated with the colored coupler is higher than the sensitivity of the emulsion associated with the colorless coupler by at least 3DIN.
Claim 8
Dependent Claim
20 words
Photographic element of claim 1 characterized by the fact that the cyan forming coupler is a phenolic or naphtholic coupler.
Claim 9
Dependent Claim
20 words
Photographic element of claim 1 characterized by the fact that the yellow colored magenta forming coupler is a pyrazolone coupler.
Claim 10
Dependent Claim
26 words
Photographic element of claim 1 characterized by having said colorless and colored couplers dispersed in their respective layers, said couplers being dissolved in water-immiscible organic solvents.
Claim 11
Dependent Claim
20 words
Photographic element of claim 1 characterized by the fact that both silver halide emulsion layers include a green sensitizing dye.
References Cited (Backward Citations)
US2509766A
Cited
US2688539A
Cited
US2994610A
Cited
US3671257A
Cited
US3637388A
Cited
GB1286831A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-07-15 | 1984-01-14 | 1984-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-15 | 1988-01-14 | 1988-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-15 | 1992-01-14 | 1992-07-15 | $7700.00 | Window Closed / Lapsed |