US4124397A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for hardening photographic silver halide emulsions
Assignee: Sterling Diagnostic Imaging Inc
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Filing: 1977-09-26
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Granted: 1978-11-07
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Expires: 1997-09-26
Abstract
Abstract A process for hardening photographic gelatino-silver halide emulsions with glutaraldehyde or substituted glutaraldehydes.
Inventors
- 👤 Werner Abele
- 👤 Wolfgang Pistor
- 👤 Manfred Schmidt
- 👤 Harry O. Smith
- 👤 Nils Spannhake
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:31
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/06; G03C1/30; Y; Y10; Y10S; Y10S430/00; Y10S430/136
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
84 words
A process for the hardening of a photographic gelatino-silver halide emulsion using glutaraldehyde or a substituted glutaraldehyde as the hardener, characterized in that (1) the hardener is continuously added to, and mixed with, a stream of the emulsion at a point between the supply vessel in which the emulsion stream originates, and a coater, and immediately before coating, and (2) the hardener is added in a concentration of less than 0.5% by weight, based on the weight of total gelatin in the emulsion stream.
Claim 2
Dependent Claim
84 words
A process for the hardening of a photographic gelatino-silver halide emulsion using glutaraldehyde or a substituted glutaraldehyde as the hardener, characterized in that (1) the hardener is continuously added to, and mixed with, a stream of the emulsion at a point between the supply vessel in which the emulsion stream originates, and a coater, and immediately before coating, and (2) the hardener is added in a concentration of less than 0.5% by weight, based on the weight of total gelatin in the emulsion stream.
Claim 3
Dependent Claim
29 words
The process of claim 1 wherein the concentration of the hardener is between 0.05 and 0.30% by weight, based on the weight of total gelatin in the emulsion stream.
Claim 4
Dependent Claim
39 words
The process of claim 1 wherein an aliphatic or aromatic sulfinic acid, or a water-soluble salt of said acid, is added to the photographic gelatino-silver halide emulsion prior to hardening, and in an amount sufficient to prevent fog formation.
Claim 5
Dependent Claim
31 words
The process of claim 1 wherein benzene sulfinic acid, or a water-soluble salt thereof, is added to the emulsion prior to hardening, and in an amount sufficient to prevent fog formation.
Claim 6
Dependent Claim
28 words
The process of claim 6 wherein said sulfinic acid, or water-soluble salt thereof, is added in a concentration of 0.5 to 15 g per mole of silver halide.
Claim 7
Dependent Claim
26 words
The process of claim 4 wherein said sulfinic acid, or water-soluble salt thereof, is added in concentration of 0.5 to 15g per mole of silver halide.
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) | 1981-11-06 | 1982-05-08 | 1982-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-06 | 1986-05-08 | 1986-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-06 | 1990-05-08 | 1990-11-07 | $7700.00 | Window Closed / Lapsed |