Patent US3926632A successfully refreshed from Google Patents.
US3926632A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photographic silver halide lith material
Assignee: Agfa Gevaert NV
•
Filing: 1972-08-11
•
Granted: 1975-12-16
•
Expires: 1992-08-11
Abstract
Abstract A method is provided of producing high contrast images by development at a temperature above 30*C of an exposed photographic light-sensitive lith-material comprising a support having thereon at least one light-sensitive silver halide emulsion, which comprises at least 50 mole percent of silver chloride and at least 5 mole percent of silver bromide, wherein the said material comprises a disulphide compound of the formula:
Inventors
- 👤 Emiel Alexander Hofman
- 👤 Jules Robert Berendsen
- 👤 Robert Joseph Pollet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:36
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/34; G03C1/346; Y; Y10; Y10S; Y10S430/00; Y10S430/15
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
116 words
METHOD OF PRODUCING A HIGH CONTRAST IMATE BY DEVELOPMENT IN A DEVELOPER WHICH CONTAINS HYDROQUINONE OR A HYDROQUINONE DRIVATIVE HAVING A LOW SULPHITE ION CONTENT AND AT A TEMPERATURE ABOVE 30*C. OF AN EXPOSED PHOTOGRAPHIC LIGHTSENSITIVE LITHMATERIAL WHICH WILL PROVIDE A CHARACTERISTIC CURVE WITH A SHORT TOE AND HIGH GAMMA AND WHICH WILL PRODUCE SHARPLY DEFINED IMAGES WITH HIGH DENSITY EXTENDING TO THE EDGES OF LINES AND DOTS COMPRISING A SUPPORT HAVING THEREON AT LEAST ONE LIGHT-SENSITIVE HIGH CONTRAST SILVER HALIDE EMULSION HAVING A FINE GRAIN, WHICH COMPRISES AT LEAST 50 MOLE PERCENT OF SILVER CHLORIDE AND AT LEAST 5 MOLE PERCENT OF SILVER BROMIDE, WIEREIN THE SAID MATERIAL COMPRISES A DISULPHIDE COMPOUND OF THE FORMULA:
Claim 2
Dependent Claim
116 words
METHOD OF PRODUCING A HIGH CONTRAST IMATE BY DEVELOPMENT IN A DEVELOPER WHICH CONTAINS HYDROQUINONE OR A HYDROQUINONE DRIVATIVE HAVING A LOW SULPHITE ION CONTENT AND AT A TEMPERATURE ABOVE 30*C. OF AN EXPOSED PHOTOGRAPHIC LIGHTSENSITIVE LITHMATERIAL WHICH WILL PROVIDE A CHARACTERISTIC CURVE WITH A SHORT TOE AND HIGH GAMMA AND WHICH WILL PRODUCE SHARPLY DEFINED IMAGES WITH HIGH DENSITY EXTENDING TO THE EDGES OF LINES AND DOTS COMPRISING A SUPPORT HAVING THEREON AT LEAST ONE LIGHT-SENSITIVE HIGH CONTRAST SILVER HALIDE EMULSION HAVING A FINE GRAIN, WHICH COMPRISES AT LEAST 50 MOLE PERCENT OF SILVER CHLORIDE AND AT LEAST 5 MOLE PERCENT OF SILVER BROMIDE, WIEREIN THE SAID MATERIAL COMPRISES A DISULPHIDE COMPOUND OF THE FORMULA:
Claim 3
Dependent Claim
50 words
Method according to claim 1, wherein the said disulphide compound has the formula: X - A1 - S - S - A2 - Y wherein each of A1 and A2 stands for C1-C7 alkylene and each of X and Y stands for a water-solubilizing group in acid or salt form.
Claim 4
Dependent Claim
49 words
Method according to claim 1, wherein the said disulphide compound has the formula: X - A1 - S - S - A2 - Y wherein each of A1 and A2 stands for phenylene and each of X and Y stands for a water-solubilizing group in acid or salt form.
Claim 5
Dependent Claim
89 words
Method according to claim 1, wherein the said disulphide compound has the formula: X - A1 - S - S - A2 - Y wherein each of A1 and A2 stands for C1-C7 alkylene and each of X and Y stands for a substituent carrying a water-solubilizing group in acid or salt form, the said substituent being a bridging benzimidazolylene, alkylene carbamoyl, alkylene sulphamoyl, arylene carbamoyl, arylene sulphamoyl, alkylene amino, alkylene acylamino or arylene acylamino group between the water-solubilizing group and the alkylene groups represented by A1 and A2.
Claim 6
Dependent Claim
90 words
Method according to claim 1, wherein the said disulphide compound has the formula: X - A1 - S - S - A2 - Y wherein each of A1 and A2 is a phenylene group and each of X and Y stands for a substituent carrying a water-solubilizing gRoup in acid or salt form, the said substituent being a bridging alkyleneoxy, alkyleneoxycarbonyl, vinylene, alkyleneoxycarbonylvinyl, alkylene carbamoyl, alkylene sulphamoyl, arylene carbamoyl, arylene sylphamoyl, alkylene acylamino or arylene acylamino group between the water-solubilizing group and the phenylene groups represented by A1 and A2.
Claim 7
Dependent Claim
32 words
Method according to claim 1, wherein the said disulphide compound is present in the silver halide emulsion in an amount comprised between 5 mg. and 1000 mg per mole of silver halide.
Claim 8
Dependent Claim
14 words
Method according to claim 1, wherein the said material also comprises a polyoxyethylene compound.
Claim 9
Dependent Claim
31 words
Method according to claim 1, wherein the exposed material is developed in a lith-type developer, which comprises as the only developing agent hydroquinone and which comprises a low sulphite ion content.
References Cited (Backward Citations)
US3057725A
Cited
US3062654A
Cited
US3043696A
Cited
US3226232A
Cited
US3397986A
Cited
US3447925A
Cited
US3573914A
Cited
US3615527A
Cited
US3640715A
Cited
US3647469A
Cited
US3615488A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-15 | 1979-06-16 | 1979-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-15 | 1983-06-16 | 1983-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-15 | 1987-06-16 | 1987-12-16 | $7700.00 | Window Closed / Lapsed |