Photographic couplers having a ballast containing a sulfone or sulfoxide group
AssigneeEastman Kodak Company
InventorsSundaram Krishnamurthy, Stanley W. Cowan
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Abstract
Novel photographic silver halide materials contain dye-forming couplers represented by formula (I): ##STR1## wherein K is a coupler moiety based on pyrazolone, phenol, naphthol, enamine, or acylacetamide to which the ballast group is attached, are useful in photographic materials and processes. The containing the couplers exhibit increased coupling activity, and provide formation of dyes having improved maximum magenta image dye density, contrast, and development speed.
Claims10
A photographic element comprising a support bearing at least one photographic silver halide emulsion layer and a dye-forming coupler, wherein the dye-forming coupler is represented by formula (I):
- ##STR20## wherein:
- n is 1 or 2;
- R.sup.2 is hydrogen or a substituent;
- R and R.sup.1, which may the same or different, are a substituent;
- L is selected from the group consisting of O, S, Se, Te, Si(R.sup.5).sub.2, NR.sup.5, PR.sup.5, P(O)(R.sup.5).sub.2 and NR.sup.5 SO.sub.2, wherein R.sup.5 represents hydrogen, alkyl or aryl;
- and
- K is a coupler moiety selected from the group consisting of pyrazolone, phenol, and naphthol.
Dependencies are inferred from the claim text.