Spectrally sensitized color photographic materials suitable for high temperature rapid development

Claim 1

A method for producing an image having a reduced amount of fog which comprises a step of color developing at a temperature of at least 30°C., an exposed light-sensitive silver halide material containing at least one spectrally sensitized silver halide photographic emulsion layer on a support, said emulsion layer containing at least one sensitizing dye having the halide ion concentration increasing effect which can be determined by: a. warming mixture A to 70°C., wherein mixture A comprises: Distilled water 500 ml Ammonium Bromide 20 g Sodium chloride 10 g Citric acid 50 g Gelatin 70 g b. adding mixture B to mixture A with agitation over 50 minutes, wherein mixture B comprises: Distilled water 500 ml Silver Nitrate 50 g Citric acid 50 g c. physically aging, cooling, setting and washing with water the product from Step (b) to yield an emulsion with a pH of 6.4 and a pAg of 7.8; d. charging a first and a second emulsion vessel each with 100 g. of the product from Step (c), melting at 40°C., stirring and storing the two emulsions; e. adding a sensitizing dye to the first emulsion vessel as a methanol solution in a concentration of 1 × 10 - 3 or 5 × 10 - 4 mol, stirring and allowing said first emulsion to stand for about 10 minutes; f. adding the quantity of methanol used in Step (e) to the said second emulsion; g. measuring any potential difference (ΔEAg) between said two emulsions; h. determining the increase or decrease in the pAg of the said first emulsion from the measurement of the ΔEAg; and i. choosing those dyes which cause an increase in the pAg of the first emulsion.

Claim 2

A method for producing an image having a reduced amount of fog which comprises a step of color developing at a temperature of at least 30°C., an exposed light-sensitive silver halide material containing at least one spectrally sensitized silver halide photographic emulsion layer on a support, said emulsion layer containing at least one sensitizing dye having the halide ion concentration increasing effect which can be determined by: a. warming mixture A to 70°C., wherein mixture A comprises: Distilled water 500 ml Ammonium Bromide 20 g Sodium chloride 10 g Citric acid 50 g Gelatin 70 g b. adding mixture B to mixture A with agitation over 50 minutes, wherein mixture B comprises: Distilled water 500 ml Silver Nitrate 50 g Citric acid 50 g c. physically aging, cooling, setting and washing with water the product from Step (b) to yield an emulsion with a pH of 6.4 and a pAg of 7.8; d. charging a first and a second emulsion vessel each with 100 g. of the product from Step (c), melting at 40°C., stirring and storing the two emulsions; e. adding a sensitizing dye to the first emulsion vessel as a methanol solution in a concentration of 1 × 10 - 3 or 5 × 10 - 4 mol, stirring and allowing said first emulsion to stand for about 10 minutes; f. adding the quantity of methanol used in Step (e) to the said second emulsion; g. measuring any potential difference (ΔEAg) between said two emulsions; h. determining the increase or decrease in the pAg of the said first emulsion from the measurement of the ΔEAg; and i. choosing those dyes which cause an increase in the pAg of the first emulsion.

Claim 10

A method for suppressing fog in high temperature color development of an exposed light-sensitive silver halide material containing at least one spectrally sensitized silver halide photographic emulsion layer on a support, wherein said emulsion layer contains at least one sensitizing dye chosen by a consideration of the halide concentration increasing effect of the dye which can be determined by: a. warming mixture A to 70°C., wherein mixture A comprises: Distilled water 500 ml Ammonium bromide 20 g Sodium chloride 10 g Citric acid 50 g Gelatin 70 g b. adding mixture B to mixture A with agitation over 50 minutes, wherein mixture B comprises: Distilled water 500 ml Silver nitrate 50 g Citric acid 50 g c. physically aging, cooling, setting and washing with water the product from Step (b) to yield an emulsion with a pH of 6.4 and a pAg of 7.8; d. charging a first and a second emulsion vessel each with 100 g. of the product from Step (c), melting at 40°C., stirring and storing the two emulsions; e. adding a sensitizing dye to the first emulsion vessel as a methanol solution in a concentration of 1 × 10 - 3 or 5 × 10 - 4 mol, stirring and allowing said first emulsion to stand for about 10 minutes; f. adding the quantity of methanol used in Step (e) to the said second emulsion; g. measuring any potential difference (ΔEAg) between said two emulsions; h. determining the increase or decrease in the pAg of the said first emulsion from the measurement of the ΔEAg; and i. choosing those dyes which cause an increase in the pAg of the first emulsion.

Claim 11

A method for suppressing fog in high temperature color development of an exposed light-sensitive silver halide material containing at least one spectrally sensitized silver halide photographic emulsion layer on a support, wherein said emulsion layer contains at least one sensitizing dye chosen by a consideration of the halide concentration increasing effect of the dye which can be determined by: a. warming mixture A to 70°C., wherein mixture A comprises: Distilled water 500 ml Ammonium bromide 20 g Sodium chloride 10 g Citric acid 50 g Gelatin 70 g b. adding mixture B to mixture A with agitation over 50 minutes, wherein mixture B comprises: Distilled water 500 ml Silver nitrate 50 g Citric acid 50 g c. physically aging, cooling, setting and washing with water the product from Step (b) to yield an emulsion with a pH of 6.4 and a pAg of 7.8; d. charging a first and a second emulsion vessel each with 100 g. of the product from Step (c), melting at 40°C., stirring and storing the two emulsions; e. adding a sensitizing dye to the first emulsion vessel as a methanol solution in a concentration of 1 × 10 - 3 or 5 × 10 - 4 mol, stirring and allowing said first emulsion to stand for about 10 minutes; f. adding the quantity of methanol used in Step (e) to the said second emulsion; g. measuring any potential difference (ΔEAg) between said two emulsions; h. determining the increase or decrease in the pAg of the said first emulsion from the measurement of the ΔEAg; and i. choosing those dyes which cause an increase in the pAg of the first emulsion.