Cyanoethyl-containing blocked development restrainers
AssigneeEastman Kodak Company
InventorsHowell Allen Hammond, Wilbert Jeptha Humphlett, Ilmari Fritiof Salminen
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Abstract
Photographic elements are disclosed which contain a blocked development restrainer which is designed to provide timely release of a development restrainer when the photographic element is processed with an alkaline processing composition. The photographic elements are especially useful in image-transfer film units where the blocked development restrainers will permit initial development to occur and, upon cleavage, will substantially restrain further development.
Claims33
A photographic element comprising a support and at least one layer thereon containing a silver halide emulsion having associated therewith a blocked development restrainer of the formula:
- ##STR11## wherein Z represents the nonmetallic atoms necessary to form a nucleus which completes a 5- or 6-membered heterocyclic ring on said structure;
- R is a cyano grup;
- and R.sup.1 and R.sup.2 can each be hydrogen atoms, alkyl groups or aryl groups, provided that at least one of R.sup.1 and R.sup.2 is a hydrogen atom.
A photographic element comprising a support and at least one layer thereon containing a silver halide emulsion having associated therewith a blocked development restrainer of the formula:
- ##STR14##
In an image-transfer film unit comprising:
- a. a photosensitive element comprising a support having thereon at least one layer containing a silver halide emulsion having associated therewtih an image dye-providing material,
- b. an image-receiving layer and
- c. means containing an alkaline processing composition adapted to discharge its contents within said film unit,
- the improvement wherein said silver halide emulsion has associated therewith a blocked development restrainer of the formula:
- ##STR15## wherein Z represents the nonmetallic atoms necessary to form an uncharged nucleus which completes a 5- or 6-membered heterocyclic ring on said structure;
- R is a cyano group;
- and R.sup.1 and R.sup.2 can each be hydrogen atoms, alkyl groups or aryl groups, provided at least one of R.sup.1 and R.sup.2 is a hydrogen atom.
An image-transfer film unit adapted to be processed by passing said unit between a pair of juxtaposed pressure-applying members comprising:
- a. a photosensitive element comprising a support having thereon a layer containing a silver halide emulsion having associated therewith an image dye-providing material,
- b. an image-receiving layer,
- c. a cover sheet superposed or adapted to be superposed on said photosensitive element and
- d. a means for discharging an alkaline processing composition within said film unit,
- wherein at least one layer between said support and said cover sheet of said film unit contains a blocked development restrainer having the formula:
- ##STR16## wherein Z represents the nonmetallic atoms necessary to form a nucleus which completes a 5- or 6-membered heterocyclic ring on said structure;
- R is a cyano group;
- and R.sup.1 and R.sup.2 can each be hydrogen atoms, alkyl groups or aryl groups, provided at least one of R.sup.1 and R.sup.2 is a hydrogen atom.
A film unit according to clam 20 wherein each of said layers containing silver halide emulsions has associated therewith an image dye-providing material.
In a process for producing a photographic transfer image comprising:
- a. imagewise-exposing a photosensitive element comprising a support having thereon a layer containing a silver halide composition having associated therewith an image dye-providing material,
- b. treating said photosensitive element with an alkaline processing composition to effect development of said exposed silver halide emulsion layer,
- c. forming an imagewise distribution of diffusible image dye-providing material as a function of development of said silver halide emulsion layer, and
- d. at least a portion of said imagewise distribution of diffusible image dye-providing material diffusing to an image-receiving layer,
- the improvement wherein said silver halide emulsion has associated therewith a blocked development restrainer of the formula:
- ##STR18## wherein Z represents the nonmetallic atoms necessary to form an uncharged nucleus which completes a 5- or 6-membered heterocyclic ring on said structure;
- R is a cyano group;
- and R.sup.1 and R.sup.2 can each be hydrogen atoms, alkyl groups or aryl groups.
Dependencies are inferred from the claim text.