Abstract: Tabular grain emulsions of enhanced photographic sensitivity are disclosed in which the tabular grains contain a maximum surface iodide concentration along their edges and a lower surface iodide concentration within their corners than elsewhere along their edges. The grains contain a dopant capable of providing shallow electron trapping sites.

Abstract: A photographically useful high bromide tabular grain silver halide emulsion is disclosed in which iodide is incorporated in a tabular grain central region to lower contrast and in a peripheral region zone to increase photoefficiency. A further increase in photoefficiency is provided by an annular spacer region interposed between the central region and peripheral region zone having a lower iodide content than either.

Abstract: Photographic print elements are disclosed of enhanced speed and controlled minimum densities provided by emulsion layer units that contain emulsions that are blends of (a) cubical silver iodochloride grains that contain iodide in a controlled, non-uniform distribution forming a core containing at least half of total silver, a iodide-free surface shell having a thickness of greater than 25 .ANG., and a sub-surface shell that contains a maximum iodide concentration and (b) minimum density controlling silver halide grains that are of smaller mean grain size than the silver iodochloride grains and that consist essentially of chloride and/or bromide and are present in a molar concentration at least equal to that of silver iodide in the silver iodochloride grains.

Abstract: A photosensitive emulsion is disclosed comprised of a dispersing medium and silver halide grains containing at least 80 mole percent bromide, based on silver, wherein at least 50% of the projected area of said silver halide grains is accounted for by tabular grains free of twin planes having {100} parallel major faces, said emulsion being chemically sensitized and having a reciprocity failure of less than 35 sensitivity units between exposures of respectively 10.sup.-5 seconds and 100 seconds. The emulsion can be employed as a latent image forming emulsion in a photographic element.The emulsion can be prepared by a process preparing a silver bromide photosensitive emulsion, comprising the following essential steps: (a) a nucleation step whereby a fine-grain emulsion with a pAg of between 4 and 6.

Abstract: A photographic element is disclosed comprised of a layer containing radiation-sensitive silver halide grains and a vehicle which can be chill set and is in part derived from gelatin and in part derived from water dispersible starch.

Abstract: A photographic print element is disclosed having a reflective support and at least one image recording emulsion layer unit containing cube-like silver iodochloride grains containing from 0.05 to 3 mole percent iodide, based on total silver, in a controlled, non-uniform iodide distribution forming a core, an iodide-free surface shell having a thickness of greater than 50 .ANG., and a sub-surface shell that contains a maximum iodide concentration.

Abstract: A photographic emulsion is disclosed comprised of coprecipitated radiation-sensitive silver halide grains containing greater than 70 mole percent bromide, based on silver, and exhibiting a coefficient of variation of less than 30 percent. Greater than 90 percent of total projected area of the grains is accounted for by tabular grains having {111} major faces, exhibiting a thickness of less than 0.07 .mu.m, and having latent image forming silver salt epitaxy chemical sensitization sites on their surfaces, and a dispersing medium that contains a grain dispersity reducing concentration of a polyalkylene oxide block copolymer surfactant comprised of two terminal lipophilic alkylene oxide block units linked by a hydrophilic alkylene oxide block unit accounting for from 4 to 96 percent of the molecular weight of the polymer.

Abstract: A radiation-sensitive photographic emulsion is disclosed containing a gelatino-vehicle and tabular grains accounting for at least 70 percent of total grain projected area comprised of, prior to house conversion, at least 90 mole percent bromide and, after house conversion, up to 12 mole percent iodide, based on total silver, having {111} major faces that form corners joined by linear edges, and containing halide conversion dislocations that are confined to corner regions.Superior performance and selected site halide conversion can be realized by maintaining a pBr of less than 3.5 and by employing for halide conversion an iodide ion source exhibiting a second order reaction rate constant with the gelatino-vehicle of less than 10.sup.-3 mole.sup.-1 sec.sup.-1.

Abstract: A radiographic element is disclosed in which from 10 to 60 percent of total silver forming the spectral sensitized silver halide grains is provided by one or more ultrathin tabular grain emulsions. It has been discovered that by limiting the proportions of ultrathin tabular grains desirably cold image tones can be obtained while improving other performance characteristics, including achieving significant reductions in crossover.

Abstract: A radiographic element is disclosed having a transparent film support and hydrophilic colloid layers including at least one silver halide emulsion layer coated on the support. Upon viewing following imagewise exposure and processing, the radiographic element exhibits a transparent blue appearance in areas of minimum density, at least a portion of the blue appearance being attributable to the presence in one or more of the hydrophilic colloid layers of at least one ionic linear condensation polymer containing an anthraquinone dye chromophore.

Abstract: Radiation-sensitive emulsions are disclosed comprised of high bromide tabular grains containing a peripheral band of increased iodide concentration. The tabular grains exhibit an average equivalent circular diameter of at least 2.0 .mu.m and are of a face centered cubic crystal lattice structure of the rock salt type. The tabular grains include central and peripheral regions extending between their major faces. The peripheral region is up to 0.2 .mu.m in width and contains an iodide concentration at least 2 mole percent higher than that of the central region measured at a location adjacent the peripheral region. Dislocations are present in the peripheral region to increase sensitivity and are minimized in the central region to maintain relatively constant sensitivities when pressure is applied locally.

Abstract: A photographic emulsion is disclosed comprised of a dispersing medium and radiation-sensitive grains with greater than 50 percent of total grain projected area being accounted for by tabular grains comprised of (1) a tabular host portion containing greater than 50 mole percent bromide, based on silver, and having spaced parallel {111} major faces, (2) a first epitaxial phase containing greater than 90 mole percent iodide, based on silver, accounting for less than 60 percent of total silver and overlying from 15 to 90 percent of the major faces, and (3) surface silver halide of a face centered cubic crystal lattice structure overlying at least a portion of the first epitaxial phase.

Abstract: (Barium halfnate:Cu) phosphors and phosphor screens. The phosphor screens include a support and a luminescent portion. The phosphor includes oxygen and a combination of species characterized by the relationship: (Ba.sub.1-q M.sub.q)(Hf.sub.1-z-e Zr.sub.z Mg.sub.e):yT where M is selected from the group consisting of Ca and Sr and combinations thereof; T is Cu; q is from 0 to 0.15; z is from 0 to 1; e is from 0 to 0.10; z+e is from 0 to 1; and y is from 1.times.10.sup.-6 to 0.02.

Abstract: A photographic emulsion comprised of high chloride radiation-sensitive tabular grains comprised of a tabular host portion containing greater than 50 mole percent chloride, based on silver, and having spaced parallel {100} major faces, a high chloride shell accounting for at least 4 percent of total silver surrounding the host portion and, interposed between the shell and the host portion an internal epitaxial phase containing greater than 90 mole percent iodide, based on silver, overlying from 15 to 90 percent of the major faces of the host portion.

Abstract: A photographic emulsion is disclosed in which radiation-sensitive silver halide grains are present containing (a) a continuous silver halide phase of a face centered cubic rock salt crystal lattice structure and (b) a discontinuous phase in the form of discrete islands separated by and surrounded by the continuous phase, each of the islands exhibiting a silver iodide crystal lattice structure.

Abstract: Phosphor screens, cesium-zinc halide phosphors, and preparation methods. The phosphor screens comprising a support and a luminescent portion including phosphor comprising oxygen and a combination of species characterized by the relationship:(Cs.sub.1-r Rb.sub.r).sub.3+v-n (Zn.sub.1-m Mg.sub.m).sub.1-o (Li.sub.a Na.sub.b K.sub.c)(Ca.sub.f Sr.sub.g Ba.sub.h)Br.sub.5+v-z-i Cl.sub.z I.sub.i :jAwherein A is selected from the group consisting of Eu, Tb, Ce, Tm, Dy, Pr, Ho, Nd, Yb, Er, Gd, Lu, Sm, Y, Tl, Na, Ag, Cu, Mg, Pb, Bi, Mn, and In, and combinations thereof; r is from 0 to 1; v is from about -0.01 to about +1; n is from 0 to about 1.5; n=a+b+c; m is from 0 to 0.5; o=f+g+h; a is from 0 to 0.3; b is from 0 to 0.75; c is from 0 to 0.75; f is from 0 to 0.25; g is from 0 to 0.5; h is from 0 to 0.5; z+i is from 0 to 5; z is from 0 to 5; i is from 0 to 0.5; and j is from 0 to 0.15.

Abstract: A radiation-sensitive emulsion is disclosed comprised of a dispersing medium and a coprecipitated grain population having a coefficient of variation of less than 30 percent. The coprecipitated grain population consists essentially of tabular grains containing greater than 50 mole percent bromide, based on silver, and having {111} major faces. The dispersing medium is comprised of (a) a cationic starch peptizer and (b) a polyalkylene oxide block copolymer surfactant.

Abstract: A photographic emulsion is disclosed comprised of a radiation-sensitive high bromide tabular grain emulsion. At least 50 percent of total grain projected area is accounted for by tabular grains each comprised of (a) less than 12 mole percent iodide and greater than 50 mole percent bromide, based on silver, (b) a central region accounting for at least 50 percent of grain projected area, and (c) a peripheral region containing crystal lattice dislocations and a higher iodide concentration than the overall average iodide concentration of the tabular grains. The emulsion contains a hydrophilic colloid peptizer derived from a water dispersible cationic starch.The iodide and dislocations in the peripheral regions contribute to increased photographic speeds. The water dispersing cationic starch facilitates emulsion precipitation and chemical sensitization.

Abstract: A color recording photographic element is disclosed containing a support and, superimposed on the support, blue, green and red recording layer units. The layer unit nearest the support contains a high chloride tabular grain emulsion and an optionally esterified glycolic ether having a molecular weight of at least 300 and containing at least one thioether moiety. The layer unit farthest from the support is free of the optionally esterified glycol compound. The advantages realized are an increased imaging density range, increased sensitivity, and increased contrast.

Abstract: A dye image forming photographic element is disclosed containing at least one green or red sensitized silver halide emulsion layer containing a dye-forming coupler and silver halide grains. At least 50 percent of the projected area of the silver halide grains is accounted for by grains (a) containing greater than 50 mole percent chloride, based on silver, (b) having {100} major faces, (c) exhibiting a thickness of 0.2 .mu.m or less, (d) exhibiting a mean equivalent lent circular diameter in the range of from 3 to 6 .mu.m, and (e) including a core and a surrounding band containing a higher level of iodide ions than the core and up to 30 percent of the silver forming the grains. The photographic element exhibits a sensitivity of greater than 750, where sensitivity is measured as the reciprocal of the exposure in lux-seconds required to produce a density of 0.15 above fog when the photographic element is exposed to a 3000.degree. K.