Claims
- 1. A photographic element comprising a support bearing at least one silver halide emulsion layer, the element containing:
- a) a release compound that provides, as a function of development, an imagewise distribution of a compound A that is photographically inert in the form in which it is released, compound A being a mobile nucleophile that is released from a carrier group as a function of silver halide development; and
- b) a uniform distribution in at least one of the layers of the element of a compound B, or a precursor of compound B that under photographic processing conditions provides a uniform distribution of compound B, both compound B and its precursor being photographically inert in the form in which it is contained in the layer, both compound B and its precursor further being a photographically active group that has its active site blocked by a group which is displaceable by compound A;
- compounds A and B being such that, under photographic processing conditions, they interact to provide a photographically active group.
- 2. A photographic element of claim 1, wherein the compounds which provide compound A and compound B are in the same layer.
- 3. A photographic element of claim 1, wherein the compounds which provide compound A and compound B are in different layers.
- 4. A photographic element of claim 3, wherein one of compound A and compound B are in a layer free of silver halide emulsion.
- 5. A photographic element of claim 1 wherein compound B has the structural formula: ##STR25## wherein: BALL is a ballast group which renders the compound immobile in the layer in which it is coated;
- TIME is a timing group;
- n is 0 or 1; and
- PAG is a development inhibitor.
- 6. A photographic element of claim 1, wherein the compound which provides compound A is selected from: ##STR26## and the compound B is selected from ##STR27##
- 7. A photographic element of claim 1, wherein the photographically active group is selected from development inhibitors, development accelerators and bleach accelerators.
- 8. A photographic element of claim 1, wherein the nucleophile is an aryl, alkyl or heterocyclic thiol.
- 9. A photographic element of claim 1, wherein compound B has the structural formula: ##STR28## wherein: X is N or C--R;
- R is H or a monovalent substituent;
- BALL is a ballast group which renders the compound immobile in the layer in which it is coated;
- TIME is a timing group;
- n is 0, 1 or 2; and
- PAG is a photographically active group.
- 10. A photographic element of claim 1, wherein compound B has the structural formula: ##STR29## wherein: Y is O, S, or N--R;
- Z is N or C--R;
- R is H or a monovalent substituent;
- BALL is a ballast group which renders the compound immobile in the layer in which it is coated;
- TIME is a timing group;
- n is 0, 1, or 2; and
- PAG is a photographically useful group.
- 11. A photographic element of claim 1, wherein the compound which provides compound A is a pyrazolone coupler that has a thiol nucleophile in its coupling position.
- 12. A photographic element of claim 1, wherein compound B has the structural formula: ##STR30## wherein: BALL is a ballast group which renders the compound immobile in the layer in which it is coated;
- TIME is a timing group;
- n is 0 or 1;
- PAG is a development inhibitor.
- 13. A photographic element comprising a support bearing at least one silver halide emulsion layer, the element containing:
- a) a release compound that provides, as a function of development, an imagewise distribution of a compound A that is photographically inert in the form in which it is released; and
- b) a uniform distribution in at least one of the layers of the element of a compound B, or a precursor of compound B that under photographic processing conditions provides a uniform distribution of compound B, each of compound B and its precursor being photographically inert in the form in which it is contained in the layer;
- compounds A and B being such that, under photographic processing conditions, they interact to provide a photographically active group;
- at least one of compounds A and B providing a nucleophile, other than an amine or oxygen nucleophile, which interacts with the other of the compounds to provide the photographically active compound.
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of Ser. No. 07/890,905 filed May 29, 1992 which is incorporated herein by reference.
US Referenced Citations (18)
Foreign Referenced Citations (4)
Number |
Date |
Country |
0335319 |
Oct 1989 |
EPX |
0167168 |
Nov 1989 |
EPX |
3506805 |
Sep 1985 |
DEX |
3153236A |
Jul 1991 |
JPX |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
890905 |
May 1992 |
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