Very low coefficient of variation tabular grain emulsion

A photographic emulsion containing a vehicle and a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent, based on the total grains of said population, said grain population containing at least 80 mole percent bromide, based on silver, and consisting essentially of tabular grains having a mean thickness in the range of from 0.080 to 0.3 .mu.m and a mean tabularity of greater than 8, the vehicle comprising a gelatino-peptizer containing at least 30 micromoles per gram of methionine and a polyalkylene oxide block copolymer surfactant having a molecular weight in the range of from 760 to 16,000 satisfying the formula:

• LAO1--HAO1--LAO1
• where
• LAO1 in each occurrence represents a terminal lipophilic alkylene oxide block unit containing at least six --OCH(CH.sub.3)CH.sub.2 -- repeating units and
• HAOl represents a hydrophilic alkylene oxide block linking unit containing --OCH.sub.2 CH.sub.2 -- repeating units forming 5 to 85 percent of the total surfactant molecular weight.

A photographic emulsion containing a vehicle and a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent, based on the total grains of said population, said grain population containing at least 90 mole percent bromide, based on silver, and consisting essentially of tabular grains having a mean thickness in the range of from 0.080 to 0.3 .mu.m and a mean tabularity of greater than 8, the vehicle comprising a gelatino-peptizer containing at least 30 micromoles per gram of methionine and a polyalkylene oxide block copolymer surfactant having a molecular weight in the range of from 1000 to 10,000 satisfying the formula:

• LAO1--HAO1--LAO1
• where
• LAO1 in each occurrence represents a terminal lipophilic alkylene oxide block unit containing at least seven --OCH(CH.sub.3)CH.sub.2 -- repeating units and
• HAO1 represents a hydrophilic alkylene oxide block linking unit containing --OCH.sub.2 CH.sub.2 -- repeating units forming 10 to 80 percent of the total surfactant molecular weight.

A photographic emulsion containing a vehicle and a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent, based on the total grains of said population, said grain population containing at least 80 mole percent bromide, based on silver, and consisting essentially of tabular grains having a mean thickness in the range of from 0.080 to 0.3 .mu.m and a mean tabularity of greater than 8, the vehicle comprising a gelatino-peptizer containing less than 30 micromoles per gram of methionine and a polyalkylene oxide block copolymer surfactant having a molecular weight in the range of from 760 to 16,000 satisfying the formula:

• LAO1--HAO1--LAO1
• where
• LAO1 in each occurrence represents a terminal lipophilic alkylene oxide block unit containing at least six --OCH(CH.sub.3)CH.sub.2 -- repeating units and
• HAO1 represents a hydrophilic alkylene oxide block linking unit containing --OCH.sub.2 CH.sub.2 --repeating units forming 4 to 35 percent of the total surfactant molecular weight.

A photographic emulsion containing a vehicle and a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent, based on the total grains of said population, said grain population containing at least 90 mole percent bromide, based on silver, and consisting essentially of tabular grains having a mean thickness in the range of from 0.080 to 0.3 .mu.m and a mean tabularity of greater than 8, the vehicle comprising a gelatino-peptizer containing less than 30 micromoles per gram of methionine and a polyalkylene oxide block copolymer surfactant having a molecular weight in the range of from 1000 to 10,000 satisfying the formula:

• LAO1--HAO1--LAO1
• where
• LAO1 in each occurrence represents a terminal lipophilic alkylene oxide block unit containing at least seven --OCH(CH.sub.3)CH.sub.2 -- repeating units and
• HAO1 represents a hydrophilic alkylene oxide block linking unit containing --OCH.sub.2 CH.sub.2 -- repeating units forming 10 to 30 percent of the total surfactant molecular weight.

A photographic emulsion containing a vehicle and a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent, based on the total grains of said population, said grain population containing at least 80 mole percent bromide, based on silver, and consisting essentially of tabular grains having a mean thickness in the range of from 0.080 to 0.3 .mu.m and a mean tabularity of greater than 8, the vehicle comprising a gelatino-peptizer containing at least 30 micromoles per gram of methionine and a polyalkylene oxide block copolymer surfactant having a molecular weight in the range of from 800 to 30,000 satisfying the formula:

• HAO2--LAO2--HAO2
• where
• HAO2 in each occurrence represents a terminal hydrophilic alkylene oxide block unit containing --OCH.sub.2 CH.sub.2 -- repeating units and
• LAO2 represents a lipophilic alkylene oxide block linking unit containing at least thirteen --OCH(CH.sub.3)CH.sub.2 -- repeating units and accounting for from 15 to 95 percent of the total surfactant molecular weight.

A photographic emulsion containing a vehicle and a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent, based on the total grains of said population, said grain population containing at least 90 mole percent bromide, based on silver, and consisting essentially of tabular grains having a mean thickness in the range of from 0.080 to 0.3 .mu.m and a mean tabularity of greater than 8, the vehicle comprising a gelatino-peptizer containing at least 30 micromoles per gram of methionine and a polyalkylene oxide block copolymer surfactant having a molecular weight in the range of from 1000 to 20,000 satisfying the formula:

• HAO2--LAO2--HAO2
• where
• HAO2 in each occurrence represents a terminal hydrophilic alkylene oxide block unit containing --OCH.sub.2 CH.sub.2 -- repeating units and
• LAO2 represents a lipophilic alkylene oxide block linking unit containing at least thirteen --OCH(CH.sub.3)CH.sub.2 -- repeating units and accounting for from 20 to 90 percent of the total surfactant molecular weight.

A photographic emulsion containing a vehicle and a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent, based on the total grains of said population, said grain population containing at least 80 mole percent bromide, based on silver, and consisting essentially of tabular grains having a mean thickness in the range of from 0.080 to 0.3 .mu.m and a mean tabularity of greater than 8, the vehicle comprising a gelatino-peptizer containing less than 30 micromoles per gram of methionine and a polyalkylene oxide block copolymer surfactant having a molecular weight in the range of from 800 to 30,000 satisfying the formula:

• HAO2--LAO2--HAO2
• where
• HAO2 in each occurrence represents a terminal hydrophilic alkylene oxide block unit containing --OCH.sub.2 CH.sub.2 -- repeating units and
• LAO2 represents a lipophilic alkylene oxide block linking unit containing at least thirteen --OCH(CH.sub.3)CH.sub.2 -- repeating units and accounting for from 40 to 96 percent of the total surfactant molecular weight.

A photographic emulsion containing a vehicle and a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent, based on the total grains of said population, said grain population containing at least 90 mole percent bromide, based on silver, and consisting essentially of tabular grains having a mean thickness in the range of from 0.080 to 0.3 .mu.m and a mean tabularity of greater than 8, the vehicle comprising a gelatino-peptizer containing less than 30 micromoles per gram of methionine and a polyalkylene oxide block copolymer surfactant having a molecular weight in the range of from 1000 to 20,000 satisfying the formula:

• HAO2--LAO2--HAO2
• where
• HAO2 in each occurrence represents a terminal hydrophilic alkylene oxide block unit containing --OCH.sub.2 CH.sub.2 -- repeating units and
• LAO2 represents a lipophilic alkylene oxide block linking unit containing at least thirteen --OCH(CH.sub.3)CH.sub.2 -- repeating units and accounting for from 60 to 90 percent of the total surfactant molecular weight.

A photographic emulsion containing a vehicle and a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent, based on the total grains of said population, said grain population containing at least 80 mole percent bromide, based on silver, and consisting essentially of tabular grains having a mean thickness in the range of from 0.080 to 0.3 .mu.m and a mean tabularity of greater than 8, the vehicle comprising a gelatino-peptizer containing at least 30 micromoles per gram of methionine and a polyalkylene oxide block copolymer surfactant having a molecular weight in the range of from 1,100 to 60,000 satisfying the formula:

• (H--HAO3--LAO3).sub.2 --L--(LAO3--HAO3--H).sub.2
• where
• L represents an ethylene diamine linking unit,
• LAO3 in each occurrence represents a lipophilic alkylene oxide block unit containing at least three --OCH(CH.sub.3)CH.sub.2 -- repeating units,
• HAO3 in each occurrence represents a hydrophilic alkylene oxide block unit containing --OCH.sub.2 CH.sub.2 -- repeating units, and
• L and LAO3 in all occurrences together account for 15 to 95 percent of the total surfactant molecular weight.

A photographic emulsion containing a vehicle and a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent, based on the total grains of said population, said grain population containing at least 80 mole percent bromide, based on silver, and consisting essentially of tabular grains having a mean thickness in the range of from 0.080 to 0.3 .mu.m and a mean tabularity of greater than 8, the vehicle comprising a gelatino-peptizer containing at least 30 micromoles per gram of methionine and a polyalkylene oxide block copolymer surfactant having a molecular weight in the range of from 1,100 to 50,000 satisfying the formula:

• (H--LAO4--HAO4).sub.2 --L'--(HAO4--LAO4--H).sub.2
• where
• L' represents an ethylene diamine linking unit,
• LAO4 in each occurrence represents a lipophilic alkylene oxide block unit containing at least three --OCH(CH.sub.3)CH.sub.2 -- repeating units,
• HAO4 in each occurrence represents a hydrophilic alkylene oxide block unit containing --OCH.sub.2 CH.sub.2 -- repeating units, and
• L' and LAO4 in all occurrences together account for 5 to 85 percent of the total surfactant molecular weight.