PHOTOGRAPHIC EMULSIONS

1328289 Spectrally sensitized photographic silver halide emulsions EASTMAN KODAK CO 11 Dec 1970 [12 Dec 1969] 58874/70 Heading G2C A photographic light-sensitive silver halide emulsion is spectrally sensitized with (1) a benzimidazolooxacarbocyanine dye and (2) a benzimidazoloselenacarbocyanine dye. Dye (1) preferably has the Formula:- and dye (2) preferably has the Formula:- wherein R1, R2, R3 and R4 are each alkyl, substituted alkyl (e.g. aralkyl) or cycloalkyl; R5 and R6 are each alkyl having 1-4 carbons; R7, R8, R9, R10, R11, R12, R13 and R14 are each H or halogen; R16 and R18 are each H, halogen, alkyl, cycloalkyl, alkoxy or aryl; R15 and R17 are each H, halogen, cyano, alkyl, cycloalkyl, alkoxy, alkylaminocarbonyl, trifluoroalkyl, trifluoroalkylsulphonyl or an acyl radical of a monobasic fatty acid; L1, L2, L3 and L4 are each a methine group which may be substituted; X1 and X2 are each an anion; and n, m, p and k are each 1 or 2; or, when R1, R2, R3 or R4 is sulphqalkyl or carboxyalkyl and X1 or X2 is a hydroxyl ion, the internal anhydride of such dye or dyes.