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US3220837A Expired / Lapsed US ⏱️ 0.0 years remaining

Diffusion transfer to stratum of a silver image inked and used in printing

Assignee: Polaroid Corp
•
Filing: 1955-07-22
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Granted: 1965-11-30
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Expires: 1975-07-22
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Abstract

No abstract record available.

Inventors

  • 👤 Edwin H Land
  • 👤 Meroe M Morse

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 18:32
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/06; G03F7/07

Claims Analysis

Total Claims: 1
Claim 1
Independent Claim 166 words
A PROCESS COMPRISING THE STEPS OF APPLYING TO A PHOTOEXPOSED SILVER HALIDE STRATUM AND A SUPERPOSED HYDROPHILIC, WATER-RECEPTIVE, SILVER-RECEPTIVE STRATUM WHICH CONTAINS NUCLEI FOR PRECIPITATION OF SILVER FROM A WATERSOLUBLE SILVER COMPLEX, AND AQUEOUS ALKALINE SOLUTION OF A SILVER HALIDE DEVELOPER AND A SILVER HALIDE SOLVENT, REDUCING THE EXPOSED SILVER HALIDE IN THE SILVER HALIDE STRATUM TO SILVER, FORMING FROM UNREDUCED SILVER HALIDE IN THE SILVER HALIDE STRATUM A WATER-SOLUBLE SILVER COMPLEX, DIFFUSING THE COMPLEX TO THE SILVER-RECEPTIVE STRATUM, PRODUCING FROM THE COMPLEX IN CONJUNCTION WITH SAID NUCLEI A VISIBLE IMAGE OF THE SILVER-RECEPTIVE STRATUM, SAID IMAGE HAVING FIRST AREAS THAT CONTAIN SILVER CONCENTRATED PRIMARILY AT THE SURFACE OF SAID SILVER-RECEPTIVE STRATUM IN THIN BUT SUBSTANTIALLY CONTINUOUS, OLEOPHILIC DENSE MASSES AND SECOND AREAS THAT ARE SUBSTANTIALLY SILVER-FREE, THEREAFTER STRIPPING THE SILVER HALIDE STRATUM FROM THE SILVER-RECEPTIVE STRATUM, COATING SAID SILVER-RECEPTIVE STRATUM WITH AN INK WHICH WILL PREFERENTIALLY WET SAID FIRST AREAS, AND PRESSING THE IMAGE ONTO A COPY SHEET IN ORDER TO TRANSFER SAID INK THERETO.

References Cited (Backward Citations)

US1811734A Cited
US2384857A Cited
US2763553A Cited
US2725298A Cited
US2702244A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1968-11-29 1969-05-31 1969-11-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1972-11-29 1973-05-31 1973-11-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1976-11-29 1977-05-31 1977-11-30 $7700.00 Window Closed / Lapsed

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