US4643965A
Expired / Lapsed
US
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Direct positive photographic light-sensitive materials
Assignee: Fujifilm Holdings Corp
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Filing: 1984-05-24
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Granted: 1987-02-17
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Expires: 2004-05-24
Abstract
Abstract A direct positive photographic light-sensitive material is described, comprising a support and at least one internal latent image type silver halide emulsion layer containing core/shell type silver halide grains which are composed of a silver halide core subjected to at least one of doping with metal ions and chemical sensitization, and a silver halide shell covering at least sensitivity sites of said core, and a binder, wherein said core/shell type silver halide grains consist of two or more kinds of grains each having a different average grain size, and the core of the core/shell type silver halide grains having a larger average grain size is doped with a larger amount of lead ions, cadmium ions, or Group VIII metal ions.
Inventors
- 👤 Satosi Kubota
- 👤 Tetsuo Yoshida
- 👤 Hideki Ohmatsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:20
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/485; G03C1/48538; G03C1/48569; G03C1/48576; Y; Y10; Y10S; Y10S430/00; Y10S430/141
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
192 words
A direct positive photographic light-sensitive material comprising a support and at least one internal latent image silver halide emulsion layer containing core/shell silver halide grains which are composed of a silver halide core containing lead ions, cadmium ions or Group VIII metal ions, and a silver halide shell covering at least sensitivity sites of said core, and a binder, wherein said core/shell silver halide grains consist of two or more kinds of grains in a same or in different emulsion layers, each said kind of grain having a different average grain size, and the core of each said kind of core/shell silver halide grains having larger average grain size is doped with lead ions, cadmium ions, or Group VIII metal ions in an amount of more than 10% higher than the amount of the smaller of said kind of grains is doped, the amount of metal ions doped is in a range of from 10 -8 to 10 -4 mols per mol of silver halide, and the difference in the average grain size between the larger grains and the smaller grains is at least 0.1μ, or 20% or more of said difference.
Claim 2
Dependent Claim
192 words
A direct positive photographic light-sensitive material comprising a support and at least one internal latent image silver halide emulsion layer containing core/shell silver halide grains which are composed of a silver halide core containing lead ions, cadmium ions or Group VIII metal ions, and a silver halide shell covering at least sensitivity sites of said core, and a binder, wherein said core/shell silver halide grains consist of two or more kinds of grains in a same or in different emulsion layers, each said kind of grain having a different average grain size, and the core of each said kind of core/shell silver halide grains having larger average grain size is doped with lead ions, cadmium ions, or Group VIII metal ions in an amount of more than 10% higher than the amount of the smaller of said kind of grains is doped, the amount of metal ions doped is in a range of from 10 -8 to 10 -4 mols per mol of silver halide, and the difference in the average grain size between the larger grains and the smaller grains is at least 0.1μ, or 20% or more of said difference.
Claim 3
Dependent Claim
18 words
A direct positive photographic light-sensitive material as in claim 1, wherein one or more monodispersed emulsions are used.
Claim 4
Dependent Claim
28 words
A direct positive photographic light-sensitive material as in claim 1, wherein the average grain size of the core/shell silver halide grains is from about 0.1 to 4 microns.
Claim 5
Dependent Claim
35 words
A direct positive photographic light-sensitive material as in claim 1, wherein the difference in the average grain size between the larger grains and the smaller grains is 20% or more in terms of the difference.
Claim 6
Dependent Claim
41 words
A direct positive photographic light-sensitive material as in claim 1, wherein the core/shell silver halide grains are doped with lead ions or cadmium ions in an amount range of from 10 -8 to 10 -4 mols per mol of silver halide.
Claim 7
Dependent Claim
40 words
A direct positive photographic light-sensitive material as in claim 1, wherein the core/shell silver halide grains are doped with Group VIII metal ions in an amount range of from 10 -8 to 10 -5 mols per mol of silver halide.
Claim 8
Dependent Claim
52 words
A direct positive photographic light-sensitive material as in claim 1, wherein the grains having a larger average grain size are doped with lead ions, cadmium ions, or Group VIII metal ions in an excess amount of more than 50% higher than the amount in the grains having a smaller average grain size.
Claim 9
Dependent Claim
52 words
A direct positive photographic light-sensitive material as in claim 1, wherein the grains having a larger average grain size are doped with lead ions, cadmium ions, or Group VIII metal ions in an excess amount of more than 100% higher than the amount in the grains having a smaller average grain size.
Claim 10
Dependent Claim
46 words
A direct positive photographic light-sensitive material as in claim 1, wherein the core/shell silver halide grains having a larger average grain size are used in an amount of from 0.1 to 10 times by weight, the weight of the grains having a smaller average grain size.
Claim 11
Dependent Claim
46 words
A direct positive photographic light-sensitive material as in claim 1, wherein the core/shell silver halide grains having a larger average grain size are used in an amount of from 1/3 to 3 times by weight, the weight of the grains having a smaller average grain size.
Claim 12
Dependent Claim
30 words
A direct positive photographic light-sensitive material as in claim 1, wherein the difference in the average grain size between the larger grains and the smaller grains is at least 0.1μ.
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) | 1990-02-16 | 1990-08-18 | 1991-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-16 | 1994-08-18 | 1995-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-16 | 1998-08-18 | 1999-02-17 | $7700.00 | Window Closed / Lapsed |