Organic disulfides as image dye stabilizers
AssigneeEastman Kodak Company
InventorSundaram Krishnamurthy
Life of this patent
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Abstract
Photographic stabilizers comprising certain organic disulfide compounds are described for incorporation in photographic emulsions and elements. The compounds are preferably employed in the magneta layer to protect the magneta dye from fading by light.
Claims20
A photographic element comprising a support having thereon at least one silver halide emulsion layer having associated therewith a dye-forming coupler and an image dye stabilizer compound having the formula:
- ##STR15## wherein each V, W, X and Y independently represents R.sup.1, nitro, halogen, cyano, OR, SR, NR.sup.1 R, COR, COOR, SO.sub.3 R, SO.sub.2 R, NHCOR, CONR.sup.1 R, NR.sup.1 SO.sub.2 R, or SO.sub.2 NR.sup.1 R, or X or W can join together with an adjacent substituent to form a ring;
- R represents a substituted or unsubstituted alkyl group of from 1 to about 20 carbon atoms;
- a substituted or unsubstituted aryl group of from about 5 to about 20 carbon atoms;
- cycloalkyl;
- or a substituted or unsubstituted heterocyclic group having from 3 to about 10 carbon atoms;
- and
- R.sup.1 represents hydrogen or R;
- with the proviso that the total number of carbon atoms within all V, W, X and Y groups combined is at least 4, and with the further proviso that at least one Y group is not hydrogen.
In a process of stabilizing a photographic dye image against fading by light comprising exposing a photographic element comprising a support having thereon at least one silver halide emulsion layer having associated therewith a dye-forming coupler in the presence of an image dye stabilizer, and color developing said element to form a dye image, the improvement wherein said stabilizer is a compound having the formula:
- ##STR16## wherein each V, W, X and Y independently represents R.sup.1, nitro, halogen, cyano, OR, SR, NR.sup.1 R, COR, COOR, SO.sub.3 R, SO.sub.2 R, NHCOR, CONR.sup.1 R, NR.sup.1 SO.sub.2 R, or SO.sub.2 NR.sup.1 R, or X or W can join together with an adjacent substituent to form a ring;
- R represents a substituted or unsubstituted alkyl group of from 1 to about 20 carbon atoms;
- a substituted or unsubstituted aryl group of from about 5 to about 20 carbon atoms;
- cycloalkyl;
- or a substituted or unsubstituted heterocyclic group having from 3 to about 10 carbon atoms;
- and
- R.sup.1 represents hydrogen or R;
- with the proviso that the total number of carbon atoms within all V, W, X and Y groups combined is at least 4, and with the further proviso that at least one Y group is not hydrogen.
A processed photographic element comprising a support having thereon a dye image and an image dye stabilizer compound having the formula:
- ##STR17## wherein each V, W, X and Y independently represents R.sup.1, nitro, halogen, cyano, OR, SR, NR.sup.1 R, COR, COOR, SO.sub.3 R, SO.sub.2 R, NHCOR, CONR.sup.1 R, NR.sup.1 SO.sub.2 R, or SO.sub.2 NR.sup.1 R, or X or W can join together with an adjacent substituent to form a ring;
- R represents a substituted or unsubstituted alkyl group of from 1 to about 20 carbon atoms;
- a substituted or unsubstituted aryl group of from about 5 to about 20 carbon atoms;
- cycloalkyl;
- or a substituted or unsubstituted heterocyclic group having from 3 to about 10 carbon atoms;
- and
- R.sup.1 represents hydrogen or R;
- with the proviso that the total number of carbon atoms within all V, W, X and Y groups combined is at least 4, and with the further proviso that at least one Y group is not hydrogen.
Dependencies are inferred from the claim text.