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US2852371A Expired / Lapsed US ⏱️ 0.0 years remaining

Photographic duplicating process

Assignee: Eastman Kodak Co
•
Filing: 1956-11-20
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Granted: 1958-09-16
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Expires: 1976-11-20
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Abstract

No abstract record available.

Inventors

  • 👤 William B Kendall

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 07:51
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/06

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 151 words
A PHOTOGRAPHIC PROCESS FOR PREPARING A SPIRIT DUPLICATING MASTER WHICH COMPRISES EXPOSING TO A SUBJECT A SUBSTANTIALLY UNHARDENED GELATINO-SILVER HALIDE EMULSION LAYER CONTAINING A GELATIN TANNING SILVER HALIDE DEVELOPING AGENT TEMPORARILY ADHERED TO A PAPER SUPPORT, TREATING THE EXPOSED EMULSION LAYER WITH AN ALKALINE SOLUTION TO DEVELOP A TANNED GELATIN AND SILVER IMAGE IN THE EXPOSED REGION OF THE EMULSION LAYER AND TO LEAVE UNHARDENED GELATIN AND SILVER HALIDE IN THE LESS-EXPOSED AREAS OF THE EMULSION LAYER, PRESSING THE EMULSION LAYER WHILE MOIST INTO CONTACT WITH A SECOND SUPPORT, STRIPPING THE SUPPORTS APART, LEAVING THE EMULSION LAYER ADHERED TO THE SECOND SUPPORT, PRESSING THE ADHERED EMULSION LAYER WHILE STILL MOIST AGAINST AN ABSORBENT SURFACE TO TRANSFER A STRATUM OF THE UNHARDENED EMULSION AREAS TO THE ABSORBENT SURFACE, AND THEN PRESSING SAID STRATUM AGAINST THE SURFACE OF A SPIRIT DUPLICATING MASTER SHEET TO TRANSFER PORTIONS OF SAID LAST-MENTIONED SURFACE TO SAID STRATUM.
Claim 2
Dependent Claim 151 words
A PHOTOGRAPHIC PROCESS FOR PREPARING A SPIRIT DUPLICATING MASTER WHICH COMPRISES EXPOSING TO A SUBJECT A SUBSTANTIALLY UNHARDENED GELATINO-SILVER HALIDE EMULSION LAYER CONTAINING A GELATIN TANNING SILVER HALIDE DEVELOPING AGENT TEMPORARILY ADHERED TO A PAPER SUPPORT, TREATING THE EXPOSED EMULSION LAYER WITH AN ALKALINE SOLUTION TO DEVELOP A TANNED GELATIN AND SILVER IMAGE IN THE EXPOSED REGION OF THE EMULSION LAYER AND TO LEAVE UNHARDENED GELATIN AND SILVER HALIDE IN THE LESS-EXPOSED AREAS OF THE EMULSION LAYER, PRESSING THE EMULSION LAYER WHILE MOIST INTO CONTACT WITH A SECOND SUPPORT, STRIPPING THE SUPPORTS APART, LEAVING THE EMULSION LAYER ADHERED TO THE SECOND SUPPORT, PRESSING THE ADHERED EMULSION LAYER WHILE STILL MOIST AGAINST AN ABSORBENT SURFACE TO TRANSFER A STRATUM OF THE UNHARDENED EMULSION AREAS TO THE ABSORBENT SURFACE, AND THEN PRESSING SAID STRATUM AGAINST THE SURFACE OF A SPIRIT DUPLICATING MASTER SHEET TO TRANSFER PORTIONS OF SAID LAST-MENTIONED SURFACE TO SAID STRATUM.

References Cited (Backward Citations)

US2073033A Cited
US2140648A Cited
US2363764A Cited
US2738727A Cited
US2716059A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1961-09-15 1962-03-17 1962-09-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1965-09-15 1966-03-17 1966-09-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1969-09-15 1970-03-17 1970-09-16 $7700.00 Window Closed / Lapsed

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