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US2865745A Expired / Lapsed US ⏱️ 0.0 years remaining

Photographic reproduction process

Assignee: Eastman Kodak Co
•
Filing: 1955-08-25
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Granted: 1958-12-23
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Expires: 1975-08-25
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Abstract

No abstract record available.

Inventors

  • 👤 Robert E Chan
  • 👤 Herbert B Cowden
  • 👤 William B Kendall

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 15:56
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/315

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 147 words
A METHOD OF PHOTOGRAPHIC REPRODUCTION WHICH COMPRISES EXPOSING TO A SUBJECT A SUBSTANTIALLY UNHARDENED GELATINO-SILVER HALIDE EMULSION LAYER CONTAINING A GELATIN TANNING SILVER HALIDE DEVELOPING AGENT, DEVELOPING THE EXPOSED EMULSION LAYER WITH AN ALKALINE SOLUTION TO OBTAIN A HARDENED GELATIN AND SILVER IMAGE IN THE REGION OF MOST EXPOSURE AND SUBSTANTIALLY UNHARDENED GELATIN AND SILVER HALIDE IN THE LESS EXPOSED REGIONS OF THE EMULSION LAYER, PRESSING THE DEVELOPED EMULSION LAYER WHILE MOIST WITH THE ALKALINE SOLUTION, AGAINST AN ABSORBENT SURFACE HAVING THEREON A MIXTURE OF THIOUREA AND SODIUM FORMALDEHYDE BISULFITE, THEREBY CAUSING ONLY THE UNEXPOSED REGIONS OF THE EMULSION LAYER TO ADHERE TO THE ABSORBENT SURFACE AND THE SILVER HALIDE THEREON TO BE CONVERTED TO A BLACK IMAGE, AND SEPARATING SAID RECEIVING SHEET AND EMULSION LAYER TO TRANSFER ONLY A STRATUM OF THE UNEXPOSED REGION OF THE EMULSION LAYER CONTAINING THE BLACK IMAGE TO THE RECEIVING SHEET.

References Cited (Backward Citations)

US2596756A Cited
US2675313A Cited
US2765240A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1961-12-22 1962-06-23 1962-12-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1965-12-22 1966-06-23 1966-12-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1969-12-22 1970-06-23 1970-12-23 $7700.00 Window Closed / Lapsed

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