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US4124397A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for hardening photographic silver halide emulsions

Assignee: Sterling Diagnostic Imaging Inc
•
Filing: 1977-09-26
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Granted: 1978-11-07
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Expires: 1997-09-26
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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 2026-11-03 01:36
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)

DE606528C Cited
US3342605A Cited
US3232764A Cited

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

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