Claims
- 1. A photographic element comprising at least one silver halide emulsion layer in which the silver halide is sensitized with a fragmentable electron donor compound of the formula: wherein A is a silver halide adsorptive group that contains at least one atom of N, S, P, Se, or Te that promotes adsorption to silver halide; Z is a light absorbing group; k is 1 or 2; and XY is a fragmentable electron donor moiety wherein X is an electron donor group and Y is a leaving group other than hydrogen, and wherein:1) XY has an oxidation potential between 0 and about 1.4 V; and 2) the oxidized form of XY undergoes a bond cleavage reaction to give the radical X• and the leaving fragment Y; and wherein the fragmentable electron donor compound is added to the emulsion layer after imagewise exposure of the photographic element by way of a pre-developer bath or a developer bath.
- 2. A photographic element comprising at least one silver halide emulsion layer in which the silver halide is sensitized with a fragmentable electron donor compound of the formula: wherein A is a silver halide adsorptive group that contains at least one atom of N, S, P, Se, or Te that promotes adsorption to silver halide, and Z is a light absorbing group, k is 1 or 2, and XY is a fragmentable electron donor moiety in which X is an electron donor group and Y is a leaving group other than hydrogen, and wherein:1) XY has an oxidation potential between 0 and about 1.4 V, 2) the oxidized form of XY undergoes a bond cleavage reaction to give the radical X• and the leaving fragment Y; and 3) the radical X• has an oxidation potential ≦−0.7V (that is, equal to or more negative than about −0.7V); and and wherein the fragmentable electron donor compound is added to the emulsion layer after imagewise exposure of the photographic element by way of a pre-developer bath or a developer bath.
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a divisional of application Ser. No. 09/118,714, filed Jul. 17, 1998 now U.S. Pat. No. 6,054,260, which is a C.I.P of Ser. No. 08/900,957 filed Jul. 25, 1997, abandoned entitled SILVER HALIDE LIGHT SENSITIVE EMULSION LAYER HAVING ENHANCED PHOTOGRAPHIC SENSITIVITY, by Anthony Adin, Jerome Looker, Samir Farid, Ian Gould, Stephen Godleski, Jerome Lenhard, Annabel Muenter, Lal Vishwakarma and Paul Zielinski, the entire disclosures of which are incorporated herein by reference.
US Referenced Citations (22)
Non-Patent Literature Citations (2)
Entry |
The Theory of the Photographic Process, Fourth Edition, T.H. James, Ed., pp. 265-266, (MacMillan, 1977). |
Co-pending application Ser. No. 08/900,694 (our docket No. 76145 filed Jul. 25, 1997, entitled Silver Halide Light Sensitive Emulsion Layer Having Enhanced Photographic Sensitivity, Inventor(s) Farid et al. |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
08/900957 |
Jul 1997 |
US |
Child |
09/118714 |
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US |