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US2678885A Expired / Lapsed US ⏱️ 0.0 years remaining

Preparation of photographic emulsions

Assignee: Eastman Kodak Co
•
Filing: 1950-04-08
•
Granted: 1954-05-18
•
Expires: 1970-04-08
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Abstract

No abstract record available.

Inventors

  • 👤 Henry D Porter

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 02:11
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/005; G03C1/015

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 96 words
THE METHOD OF MAKING A PHOTOGRAPHIC SILVER HALIDE EMULSION WHICH COMPRISES REACTING A CATION EXCHANGE MATERIAL CONTAINING SILVER IN THE CATION WITH AN AQUEOUS SOLUTION OF A WATERSOLUBLE HALIDE SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL, ALKALINE EARTH METAL AND AMMONIUM HALIDE IN THE PRESENCE OF AN ORGANIC PEPTIZING AGENT FOR SILVER HALIDE, THEREBY EXCHANGING THE CATION OF THE HALIDE FOR SILVER AND FORMING A DISPERSION OF SILVER HALIDE IN AN AQUEOUS SOLUTION OF THE PEPTIZING AGENT WHICH DISPERSION IS SEPARABLE FROM THE SO-MODIFIED EXCHANGE MATERIAL, AND SEPARATING SAID DISPERSION FROM THE SO-MODIFIED EXCHANGE MATERIAL.
Claim 2
Independent Claim 96 words
THE METHOD OF MAKING A PHOTOGRAPHIC SILVER HALIDE EMULSION WHICH COMPRISES REACTING A CATION EXCHANGE MATERIAL CONTAINING SILVER IN THE CATION WITH AN AQUEOUS SOLUTION OF A WATERSOLUBLE HALIDE SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL, ALKALINE EARTH METAL AND AMMONIUM HALIDE IN THE PRESENCE OF AN ORGANIC PEPTIZING AGENT FOR SILVER HALIDE, THEREBY EXCHANGING THE CATION OF THE HALIDE FOR SILVER AND FORMING A DISPERSION OF SILVER HALIDE IN AN AQUEOUS SOLUTION OF THE PEPTIZING AGENT WHICH DISPERSION IS SEPARABLE FROM THE SO-MODIFIED EXCHANGE MATERIAL, AND SEPARATING SAID DISPERSION FROM THE SO-MODIFIED EXCHANGE MATERIAL.

References Cited (Backward Citations)

US1844716A Cited
US2066271A Cited
US2452179A Cited
US2525247A Cited
US2497054A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1957-05-17 1957-11-16 1958-05-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1961-05-17 1961-11-16 1962-05-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1965-05-17 1965-11-16 1966-05-18 $7700.00 Window Closed / Lapsed

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