US4820622A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heat development image forming method
Assignee: Fujifilm Holdings Corp
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Filing: 1988-04-08
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Granted: 1989-04-11
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Expires: 2008-04-08
Abstract
Abstract An image is formed by imagewise exposing a heat-developable photosensitive material comprising (a) a photosensitive silver halide, (b) a reducing agent or a precursor thereof, (c) a dye-providing substance which forms or releases a diffusible dye in proportion or counter-proportion to the reduction of the silver halide into silver, and (d) a binder on a support, during or after the imagewise exposure of the photosensitive material, maintaining the photosensitive material in such a pH and a temperature lower than the heat-developing temperature for a predetermined time that the reaction between the silver halide and the reducing agent preferentially takes place rather than the reaction of forming or releasing a diffusible dye, and thereafter heat developing the exposed material in the presence of a base and/or a base precursor to imagewise produce a diffusible dye.
Inventors
- 👤 Hiroyuki Hirai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:32
CPC Classifications
G; G03; G03C; G03C8/00; G03C8/40; G03C8/4013
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
132 words
A method for forming an image, comprising the steps of imagewise exposing a heat-developable photosensitive material comprising at least (a) a photosensitive silver halide, (b) a reducing agent or a precursor thereof, (c) a dye-providing substance which forms or releases a diffusible dye in proportion or counter-proportion to the reduction of the silver halide into silver, and (d) a binder on a support, during or after the imagewise exposure of the photosensitive material, maintaining the photosensitive material in such conditions for a predetermined time that the reaction between the silver halide and the reducing agent preferentially takes place rather than the reaction of forming or releasing a diffusible dye, and thereafter heat developing the exposed material in the presence of a base and/or a base precursor to imagewise produce a diffusible dye.
Claim 2
Independent Claim
132 words
A method for forming an image, comprising the steps of imagewise exposing a heat-developable photosensitive material comprising at least (a) a photosensitive silver halide, (b) a reducing agent or a precursor thereof, (c) a dye-providing substance which forms or releases a diffusible dye in proportion or counter-proportion to the reduction of the silver halide into silver, and (d) a binder on a support, during or after the imagewise exposure of the photosensitive material, maintaining the photosensitive material in such conditions for a predetermined time that the reaction between the silver halide and the reducing agent preferentially takes place rather than the reaction of forming or releasing a diffusible dye, and thereafter heat developing the exposed material in the presence of a base and/or a base precursor to imagewise produce a diffusible dye.
Claim 3
Dependent Claim
50 words
The image forming method of claim 1 wherein the photosensitive material is maintained at a temperature lower than the heat-developing temperature above which the reaction of forming or releasing a diffusible dye occurs and under conditions which allow reaction to take place between the silver halide and the reducing agent.
Claim 4
Dependent Claim
31 words
The image forming method of claim 2 wherein the photosensitive material is maintained at a temperature sufficient to allow reaction to take place between the silver halide and the reducing agent.
Claim 5
Dependent Claim
26 words
The image forming method of claim 2 wherein the photosensitive material is maintained at a temperature lower than the heat-developing temperature by at least 10° C.
Claim 6
Dependent Claim
21 words
The image forming method of claim 1 wherein imageforming reaction is carried out in the presence of an auxiliary developing agent.
Claim 7
Dependent Claim
32 words
The image forming method of claim 1 wherein an internal latent image type emulsion of the silver halide is combined with a nucleating agent or secondary exposure to carry out image-forming reaction.
Claim 8
Dependent Claim
26 words
The image forming method of claim 1 wherein the exposed material is heat developed at a temperature of from about 50° C. to about 250° C.
References Cited (Backward Citations)
US4500626A
Cited
US4740446A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-10 | 1992-10-10 | 1993-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-10 | 1996-10-10 | 1997-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-10 | 2000-10-10 | 2001-04-11 | $7700.00 | Window Closed / Lapsed |