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US4812390A Expired / Lapsed US ⏱️ 0.0 years remaining

Process and element for obtaining a photographic image

Assignee: 3M Co
•
Filing: 1987-10-30
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Granted: 1989-03-14
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Expires: 2007-10-30
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Abstract

Abstract A photographic image is formed with silver halide emulsions by using optically unsensitized light sensitive (coarse) silver halide grains. Optically (or spectrally) sensitized fine grains (or crystals or particles),--especially light insensitive or Lippmann silver halide grains--, can be reactively associated with optically (or spectrally) unsensitized light sensitive (coarse) silver halide grains to get a combination of Spectrally Sensitized Fine Grains with Spectrally Unsensitized Light Sensitive or Coarse Grains, --especially Tabular Grains--, which can be imagewise exposed (to the light absorbed by the dye sensitizer adsorbed on the surface of such fine grains) and developed with substantially the same sensitivity of the light sensitive optically sensitized (coarse) silver halide grains.

Inventors

  • 👤 Pier G. Giannesi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 21:40
CPC Classifications
G; G03; G03C; G03C5/00; G03C1/00; G03C1/005; G03C1/0051; G03C5/58; G03C1/06; G03C1/08; G03C1/10; G03C1/12; G03C1/14; G03C1/18; G03C2001/0055; G03C1/035; G03C2001/03564; G03C2001/03594; G03C1/34; G03C2001/348; G03C2200/00; G03C2200/38; Y; Y10; Y10S; Y10S430/00; Y10S430/1053; Y10S430/1055; Y10S430/106

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 45 words
A process for obtaining a photographic image upon exposure and development of a silver halide emulsion characterized by exposing light insensitive optically sensitized grains and then developing light sensitive optically unsensitized silver halide grains reactively associated with such light insensitive grains during exposure and development.
Claim 2
Dependent Claim 45 words
A process for obtaining a photographic image upon exposure and development of a silver halide emulsion characterized by exposing light insensitive optically sensitized grains and then developing light sensitive optically unsensitized silver halide grains reactively associated with such light insensitive grains during exposure and development.
Claim 3
Dependent Claim 21 words
The process of claim 1 wherein said light sensitive silver halide grains have an average grain size larger than 0.2 micron.
Claim 4
Dependent Claim 19 words
The process of claim 1 wherein said light insensitive grains have an average grain size less than 0.2 micron.
Claim 5
Dependent Claim 42 words
A photographic element comprising a support base and a silver halide emulsion layer on a surface of said support base, said base including light sensitive optically unsensitized silver halide grains and light insensitive optically sensitized grains in reactive association with each other.
Claim 6
Dependent Claim 42 words
A photographic element comprising a support base and a silver halide emulsion layer on a surface of said support base, said base including light sensitive optically unsensitized silver halide grains and light insensitive optically sensitized grains in reactive association with each other.
Claim 7
Dependent Claim 17 words
The photographic element of claim 4 characterized by said light sensitive silver halide grains being tabular grains.
Claim 8
Dependent Claim 20 words
The photographic element of claim 5 wherein said silver halide tabular grains are silver bromide grains or silver bromoiodide grains.
Claim 9
Dependent Claim 48 words
The photographic element of claim 5 wherein said tabular grains have an aspect ratio of at least 8:1 and a net projected area value of at least 50 percent and said optically sensitized light insensitive grains are present in an amount of at least 5 percent by weight.
Claim 10
Dependent Claim 22 words
The photographic element of claim 4 wherein said light insensitive optically sensitized grains are silver bromide, silver bromoiodide or silver iodide grains.
Claim 11
Dependent Claim 48 words
The photographic element of claim 4 characterized by having two opposite light sensitive emulsion layers each coated on one side of said support base at least one of said emulsion layers including said light sensitive optically unsensitized silver halide grains reactively associated with light insensitive optically sensitized grains.
Claim 12
Dependent Claim 37 words
A light insensitive silver halide emulsion including silver halide grains dispersed in a hydrophilic colloid binder having adsorbed on their surface a sensitizer dye in reactive association with a optically unsensitized light sensitive silver halide grain emulsion.
Claim 13
Dependent Claim 37 words
A light insensitive silver halide emulsion including silver halide grains dispersed in a hydrophilic colloid binder having adsorbed on their surface a sensitizer dye in reactive association with a optically unsensitized light sensitive silver halide grain emulsion.
Claim 14
Dependent Claim 19 words
The process of claim 2 wherein said light insensitive grains have an average grain size less than 0.2 micron.
Claim 15
Dependent Claim 21 words
The element of claim 4 wherein said light sensitive optically unsensitized grains have an average diameter of greater than 0.2 microns.
Claim 16
Dependent Claim 22 words
The element of claim 4 wherein said light insensitive optically sensitized grains have an average grain size of less than 0.2 microns.
Claim 17
Dependent Claim 22 words
The element of claim 2 wherein said light insensitive optically sensitized grains have an average grain size of less than 0.2 microns.
Claim 18
Dependent Claim 12 words
The element of claim 12 wherein said unsensitized grains are tabular grains.
Claim 19
Dependent Claim 12 words
The element of claim 14 wherein said unsensitized grains are tabular grains.

References Cited (Backward Citations)

GB1139062A Cited
US3573057A Cited
US4229525A Cited
US4434226A Cited
US4659646A Cited
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US4727016A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-03-13 1992-09-12 1993-03-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-03-13 1996-09-12 1997-03-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-03-13 2000-09-12 2001-03-14 $7700.00 Window Closed / Lapsed

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