摘要:
The present invention is directed to a process of precipitating for use in photography a silver halide emulsion employing a gelatino-peptizer containing alkylated methionine and to an emulsion produced by this process. A variety of advantages can be realized, including an increase in the population of twinned grains and a higher yield of thin tabular grains.
摘要:
Aqueous-based thermally developable emulsions and photothermographic imaging materials include photosensitive silver halide core-shell grains that comprise at least 20 mol % iodide based on total silver, an amount of iodide in the core of the grains that can be up to the iodide saturation limit in silver iodobromide, and an amount of iodide in the shell of the grains that is at least 2 mol % less than the amount of iodide present in the core, and further provided that the total amount of silver in the shell is from about 10 to about 80 mol % of total silver in the grains. These materials provide desired Dmax and reduced image “print out”.
摘要:
A process for precipitating a high bromide silver halide emulsion in an aqueous medium is disclosed comprising growing nucleated silver halide grains in a reaction vessel in the presence of a peptizer comprising a water dispersable starch to form high bromide radiation-sensitive silver halide grains, wherein the majority of grain growth in the reaction vessel is performed at a pH of less than 3.5. Growth of high bromide silver halide emulsion grains in the presence of a starch peptizer at low pH in accordance with the invention results in emulsion grains with lower fog, even in the absence of the use of strong oxidizing agents during grain precipitation.
摘要:
A process for precipitating a high bromide silver halide emulsion in an aqueous medium is described comprising precipitating high bromide radiation-sensitive silver halide grains in a reaction vessel in the presence of a peptizer comprising a water dispersable starch, wherein a strong oxidizing agent is added to the reaction vessel during or after the precipitation at a pH of less than 4.0 such that an oxidation potential of at least 650 mV (Ag/AgCl ref.) is achieved. A reduction in the rate of reaction between strong oxidants such as bromine and starch at such low pH has been found to enable an advantageous decrease in the amount of oxidant required to achieve and maintain a high oxidation potential during emulsion grain precipitation. Starch, unlike gelatin, also advantageously has adequate stability at the combination of high acidity and high emulsion precipitation temperatures.
摘要:
A process for precipitating a high chloride silver halide emulsion in an aqueous medium is disclosed comprising growing nucleated silver halide grains in a reaction vessel in the presence of a peptizer comprising a water dispersable starch to form high chloride radiation-sensitive silver halide grains, wherein the majority of grain growth in the reaction vessel is performed at a pH of less than 3.5. Growth of high chloride silver halide emulsion grains in the presence of a starch peptizer at low pH in accordance with the invention results in emulsion grains with lower fog, even in the absence of the use of strong oxidizing agents and antifoggants during grain precipitation.
摘要:
A multicolor photographic element comprising a support bearing a cyan dye image-forming unit comprising at least one red-sensitive silver halide emulsion layer having associated therewith at least one cyan dye-forming coupler, a magenta dye image-forming unit comprising at least one green-sensitive silver halide emulsion layer having associated therewith at least one magenta dye-forming coupler, a yellow dye image-forming unit comprising at least one blue-sensitive silver halide emulsion layer having associated therewith at least one yellow dye-forming coupler, wherein at least one of said emulsion layers comprises tabular grains having {111} major faces containing greater than 50 mole percent bromide, and accounting for greater than 50 percent total grain projected area precipitated in a peptizer that is a water dispersible cationic starch, and contains a fragmentable electron donating sensitizer.
摘要:
A photographic recording element is disclosed containing in at least one dye image forming layer unit (a) a radiation-sensitive silver halide grains include tabular grains (1) having {111} major faces, (2) containing greater than 50 mole percent bromide, based on silver, and (3) accounting for greater than 50 percent total grain projected area, (b) a fragmentable electron donating sensitizer, (c) a water dispersible cationic starch peptizer, and (d) a one equivalent dye image providing coupler. Increased photographic speed is realized.
摘要:
Herein is disclosed a liquid ink jet ink for acetoacetylated poly(vinylalcohol) receivers comprising a carrier, a pigment and a hardener. A method of using the ink is also disclosed.
摘要:
A process is disclosed for preparing high chloride {100} tabular grain emulsions containing crystal lattice dislocations in peripheral regions of the tabular grains. In the initial step of the process a radiation-sensitive high chloride {100} tabular grain emulsion is produced to provide host grains. Lateral growth lateral growth of the {100} major surfaces of the tabular grains is extended by precipitating a high chloride peripheral region onto the host tabular grains. After the host grains have been provided an iodide ion source compound with a maximum second order reaction rate constant within the dispersing medium of less than 1.times.10.sup.3 mole.sup.-1 sec.sup.-1 is introduced into the host emulsion to release iodide ions for incorporation into the tabular grains at their peripheral edges by chloride ion displacement. In the resulting emulsion 10 or more crystal lattice dislocations extending inwardly from the peripheral edges of the {100} tabular grains are observed. The dislocations in the peripheral and, particularly, corner regions of the tabular grains increase their sensitivity.