Minnesota Mining and Manufacturing Company

Walter Beltramini

Ivano Delprato

Francesco Squarcia

A multilayer silver halide color photographic element comprising at least one blue-sensitive silver halide emulsion layer comprising a blue spectral sensitizing dye and a supersensitizing amount of a disulfide compound of formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, equal or different, each represents a hydrogen atom or a lower alkyl group, R.sub.5 represents a hydrogen atom, a formyl group or an acetyl group, R.sub.6 and R.sub.7, equal or different, each represents a hydrogen atom or a lower alkyl group, or R.sub.6 and R.sub.7 represent the elements needed to complete an unsaturated cyclic nucleus. The combination provides a blue-sensitive silver halide emulsion layer having high sensitivity, low fog and good resistance against fading of the latent image.

Silver halide multilayer color photographic element comprising a

Silver halide light-sensitive emulsions are protected against latent image fading by an effective amount of a 2-unsubstituted N-alkenyl-thiazolium salt compound.

Silver halide emulsion containing a 2-unsubstituted N-alkenyl-thiazolium

A high sensitivity multilayer color photographic material is disclosed. The material is comprised of a support base having coated thereon red-sensitive, green-sensitive and blue-sensitive silver halide emulsion layers associated with non-diffusing image-forming couplers. The red-sensitive silver halide emulsion layer comprises an upper, an intermediate and a lower silver halide emulsion layer, sensitive to visible light in the same or substantially the same spectral wavelength range, with the sensitivity of the layers decreasing in order from the upper layer to the lower layer. The green-sensitive silver halide emulsion layer comprises an upper and a lower silver halide emulsion layer, sensitive to visible light in about the same spectral wavelength range, with the sensitivity of the layers decreasing in order from the upper layer to the lower layer. The most sensitive red-sensitive silver halide emulsion layer is arranged between the less senitive and the more sensitive green-sensitive silver halide emulsion layers. The most sensitive red-sensitive silver halide emulsion layer comprises at least one non-diffusing cyan coupler and the more sensitive green-sensitive silver halide emulsion layer comprises at least one non-diffusing magenta coupler, relative coupling rates of said cyan and magenta couplers being higher than couplers forming the same color in the respective layers of lower same-wave-length sensitivity.

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Albissola Superiore, Italy

Walter Beltramini