Photographic silver halide material which contains color couplers
AssigneeAgfa-Gevaert
InventorsWillibald Pelz, Hans-Heinrich Credner, Walter Schulte, Alfons Klein, Karlfried Wedemeyer, Fritz Nittel
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Abstract
This invention relates to a color photographic material with at least one silver halide emulsion layer having improved stability against crystallization and which contains in dispersed form a open chain keto methylene coupler a naphtholic or pyrazolone color coupler substituted with a 2-cyclo-pentyl-4-t-butyl-phenoxy group in a non-coupling position.
Claims2
A color photographic gelatin silver halide emulsion having improved stability against crystallization characterized in that it contains in an organic solvent an effective amount of a color coupler of the following formula:
- ##SPC9##
- in which
- K represents a radical with color coupling properties selected from the group consisting of .alpha.-naphthol, pyrazolene-5 or open-chain ketomethylene groups;
- V represents a connecting link which links the 2-cyclopentyl-4-t.-butyl-phenoxy group with the coupler radical, selected from the group consisting of a --NH--(CH.sub.2).sub.n and a ##EQU2## and a --CO--O--(CH.sub.2).sub.2 group;
- R.sub.1 represents hydrogen or an alkyl radical preferably with up to 12 carbon atoms;
- and
- n equals an integer, preferably 2, 3 or 4.
The method of producing a color photographic gelatin silver halide emulsion layer in a photographic material on a support to improve the mixing of a color coupler in the silver halide emulsion which comprises the step of emulsifying with a gelatin solution, a solution of an organic solvent and a color coupler of the following formula:
- ##SPC10##
- in which
- K represents a radical with color coupling properties selected from the group consisting of .alpha.-naphthol, pyrazolone-5 or open-chain ketomethylene groups;
- V represents a connecting link which links the 2-cyclopentyl-4-t.-butyl-phenoxy group with the coupler radical, selected from the group consisting of a --NH--(CH.sub.2).sub.n and a ##EQU3## and a CO--O--(CH.sub.2).sub.2 group;
- R.sub.1 represents hydrogen or an alkyl radical preferably with up to 12 carbon atoms;
- and
- n equals an integer, preferably 2, 3 or 4 and subsequently applying the resultant emulsion on a support.
Dependencies are inferred from the claim text.