US3637387A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct positive emulsion containing a halide releasing compound developed in the presence of an unsubstituted hydrazine
Assignee: Agfa Gevaert NV
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Filing: 1967-10-24
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Granted: 1972-01-25
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Expires: 1987-10-24
Abstract
Abstract Direct positive copies obtained by imagewise exposing a lightsensitive material having a layer of a silver halide emulsion of the type that forms a latent image predominantly within the silver halide grains in which emulsion is incorporated at least one compound setting free iodide ions or at least one compound setting free bromide ions in an aqueous medium together with a fog inhibiting compound and developing thus exposed material with an energetic surface developer in the presence of an unsubstituted hydrazine or a water soluble salt thereof provided by way of the developer solution or by way of a processing liquid applied to the exposed material prior to development. Colored images can be formed as well as black and white images provided color coupling agents and color developing agents are utilized.
Inventors
- 👤 Gerard L Vanreusel
- 👤 Camille A Vandeputte
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 19:14
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/485; G03C1/48538; G03C1/48546; G03C1/48561; G03C1/48553
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
21 words
The method of claim 1 wherein said unsubstituted hydrazine or water soluble salt thereof is present in said aqueous developer solution.
Claim 2
Dependent Claim
31 words
The method of claim 1 wherein said unsubstituted hydrazine or water-soluble salt thereof is present in an aqueous processing liquid with which said light-sensitive material is wetted prior to said development.
Claim 3
Dependent Claim
41 words
The method of claim 14 wherein said unsubstituted hydrazine or water-soluble salt thereof is present in an aqueous processing liquid with which said light-sensitive material is wetted prior to said development, said liquid having a pH of at least about 10.
Claim 4
Dependent Claim
53 words
A method according to claim 1, wherein the fog-inhibiting compound is a fog-inhibiting compound of the class of the heterocyclic thione compounds, of the class of the aromatic or aliphatic mercapto compounds, of the class of the benzotriazoles, or of the class of the fused oxo compounds containing at least two nitrogen atoms.
Claim 5
Dependent Claim
12 words
A method according to claim 1, wherein the fog-inhibiting compound is 1(o-methoxy-phenyl)-2-tetrazoline-5-thione.
Claim 6
Dependent Claim
17 words
A method according to claim 1 wherein the silver halide emulsion is at most slightly chemically ripened.
Claim 7
Dependent Claim
50 words
A method according to claim 1, wherein the silver halide emulsion is a silver chlorobromide emulsion comprising at least 20 mole percent of silver bromide or a silver bromide emulsion, which emulsions may contain at most 5 mole percent of silver iodide relative to the total amount of silver halide.
Claim 8
Dependent Claim
18 words
A method according to claim 8, wherein the silver halide emulsion is prepared by the so-called conversion method.
Claim 9
Dependent Claim
25 words
A method according to claim 1, wherein a polyalkylene glycol is present in the light-sensitive material in effective contact with the silver halide emulsion layer.
Claim 10
Dependent Claim
14 words
A method according to claim 1, wherein the silver halide emulsion comprises polyvinyl pyrrolidone.
Claim 11
Dependent Claim
14 words
A method according to claim 1, wherein the silver halide emulsion comprises a latex.
Claim 12
Dependent Claim
28 words
A method according to claim 1, wherein the pH of the processing liquid, whereto said hydrazine or water-soluble salt, thereof has been added, is at least about 10.
Claim 13
Dependent Claim
32 words
A method according to claim 1, wherein the light sensitive material is developed with an energetic color developer in the presence of a color coupler and the silver developed is bleAched away.
Claim 14
Dependent Claim
40 words
A method according to claim 14, wherein several silver halide emulsion layers constitute a multilayer color material each layer of which absorbs a particular part of the spectrum and for each of which layers an appropriate color coupler is provided.
Claim 15
Dependent Claim
53 words
A method according to claim 14, wherein the fog-inhibiting compound is a fog-inhibiting compound of the class of the heterocyclic thione compounds, of the class of the aromatic or aliphatic mercapto compounds, of the class of the benzotriazoles, or of the class of the fused oxo compounds containing at least two nitrogen atoms.
Claim 16
Dependent Claim
12 words
A method according to claim 14, wherein the fog-inhibiting compound is 1(o-methoxy-phenyl)-2-tetrazoline-5-thione.
Claim 17
Dependent Claim
17 words
A method according to claim 14, wherein the silver halide emulsion is at most slightly chemically ripened.
Claim 18
Dependent Claim
50 words
A method according to claim 14, wherein the silver halide emulsion is a silver chlorobromide emulsion comprising at least 20 mole percent of silver bromide or a silver bromide emulsion, which emulsions may contain at most 5 mole percent of silver iodide relative to the total amount of silver halide.
Claim 19
Dependent Claim
18 words
A method according to claim 19, wherein the silver halide emulsion is prepared by the so-called conversion method.
Claim 20
Dependent Claim
22 words
A method according to claim 14, wherein the light-sensitive material is overall exposed during the development to actinic light of low intensity.
Claim 21
Dependent Claim
29 words
A method according to claim 14, wherein at least part of the developing substance is present in the light-sensitive material in effective contact with the silver halide emulsion layer.
Claim 22
Dependent Claim
29 words
A method according to claim 1, wherein at least part of the developing substance is present in the light-sensitive material in effective contact with the silver halide emulsion layer.
Claim 23
Dependent Claim
20 words
The method of claim 14 wherein said unsubstituted hydrazine or water-soluble salt thereof is present in said aqueous developer solution.
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) | 1975-01-24 | 1975-07-26 | 1976-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-24 | 1979-07-26 | 1980-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-24 | 1983-07-26 | 1984-01-25 | $7700.00 | Window Closed / Lapsed |