Abstract: A process is disclosed of accelerating the preparation of a photographic emulsion containing tabular silver halide grains exhibiting a reduced degree of total grain dispersity. A dispersing medium is provided containing bromide ions, and a population of silver halide grain nuclei containing parallel twin planes is formed in the dispersing medium. A portion of the grain nuclei are ripened out, and then the silver halide grain nuclei containing parallel twin planes remaining are grown to form tabular silver halide grains. A polyalkylene oxide containing both hydrophilic and lipophilic block units is selected from among those known to be capable of reducing total grain dispersity when present during nucleation. However, in this process precipitation is accelerated while maintaining low dispersity of the total grain population by forming twin planes in the grain nuclei within the pAg and temperature boundaries of Curve A in FIG.

Abstract: A radiographic element is disclosed comprised of a film support capable of transmitting radiation to which the radiographic element is responsive having opposed major surfaces, and, coated on the opposed major surfaces, spectrally sensitized high tabularity tabular grain emulsion layer units, and, interposed between each of the emulsion layer units and the support, means for absorbing radiation to which said emulsion layer units are responsive. The emulsion layer units exhibit a coefficient of variation of less than 15 percent, based on the total grain population having an equivalent circular diameter of greater than 0.1 .mu.m, and greater than 97 percent of the projected area of grains having an equivalent circular diameter of greater than 0.1 .mu.m is accounted for by tabular grains having a mean thickness of less than 0.3 .mu.m and a halide content of from 0 to 5 mole percent chloride, from 0 to 5 mole percent iodide, and from 90 to 100 mole percent bromide, based on total silver.

Abstract: An asymmetrical radiographic element is disclosed comprised of a transparent film support, green sensitized silver halide emulsion layer units of differing sensitometric characteristics coated on opposite sides of the film support, and a processing solution decolorizable means for reducing crossover to less than 10 percent. The element is positioned between intensifying screens and mounted in a cassette for exposure to X-radiation. A processing solution decolorizable pentamethineoxonol dye with insignificant absorption at 550 nm is incorporated into an overcoat layer to distinguish which of the emulsion layer units is positioned nearest a source of X-radiation during exposure.

Abstract: A process of preparing a radiation sensitive high chloride high aspect ratio tabular grain emulsion is disclosed wherein silver ion is introduced into a high methionine gelatino-peptizer dispersing medium having a methionine content of greater than 30 .mu.moles/gram gelatin, containing a stoichiometric excess of chloride ions of greater than 0.5 molar, a pH of at least 4.5, and a 4,6-di(hydroamino)-5-aminopyrimidine grain growth modifier, such as adenine or 4,5,6 triaminopyrimidine.

Abstract: The present invention is directed to a process of precipitating, for use in photography, a high aspect ratio silver halide tabular grain emulsion employing a dispersing medium and silver chlorobromide or silver chlorobromoiodide grains, wherein at least 50 percent of the tabular silver halide grains have a centrally located hole.

Abstract: Novel tabular grain emulsions and a process for their preparation are disclosed in which silver bromoiodide tabular grains account for greater than 97 percent of total grain projected area and the coefficient of variation of the total grain population is less than 25 percent. This is achieved by forming in a first reaction vessel and transporting to a second reaction vessel a population of silver bromide grain nuclei in the form of regular octahedra having an equivalent circular diameter of less than 40 nanometers and a coefficient of variation of less than 50 percent and in the second reaction vessel converting the grain nuclei into a grain population containing parallel twin planes in more than 90 percent of the grains, so that upon further growth silver bromoiodide tabular grains of desired properties can be realized.

Abstract: The present invention is directed to hollow rod-shaped silver halide grains for use in photography and a process for preparation of hollow, rod-shaped grains. The rods have a hexagonal outer periphery, and a hexagonal hollow portion extending longitudinally within the grains.

Abstract: The present invention relates to a process of preparing radiation sensitive silver halide grains containing at least 90 mole % silver iodide and having a morphological configuration of four hexagonal bipyramids each with bases joined to form a common tetrahedron. With this process, the hexagonal bipyramid portion of the grains can be elongated and/or truncated. In addition, the fraction of silver halide grains which have a configuration of four hexagonal bipyramids is increased.

Abstract: A multicolor photographic element capable of forming a viewable reversal dye image is disclosed comprising a support and, coated on the support, a blue recording yellow dye image forming layer unit, a green recording magenta dye image forming layer unit, and a red recording cyan dye image forming layer unit, each of the dye image forming layer units containing at least one silver halide emulsion layer comprised of a vehicle and silver halide grains having (1) a halide content of from 0 to 5 mole percent chloride, from 0.1 to 20 mole percent iodide, and from 80 to 99.9 mole percent bromide, based on total silver. At least one of the silver halide emulsion layers in one of the layer units positioned to receive exposing radiation prior to at least one of the green or red recording layer units is a tabular grain emulsion layer in which a polyalkylene oxide block copolymer is present selected to allow the preparation of tabular grains having a mean thickness of less than 0.3 .mu.

Abstract: A process is disclosed of preparing an emulsion for photographic use comprised of silver halide grains and a gelatino-peptizer dispersing medium in which morphologically unstable tabular grains having {111} major faces account for greater than 50 percent of total grain projected area and contain at least 50 mole percent chloride, based on silver. The emulsion additionally contains at least one 2-hydroaminoazine absorbed to and morphologically stabilizing the tabular grains. Protonation releases 2-hydroaminoazine from the tabular grain surfaces into the dispersing medium. Released 2-hydroaminoazine is replaced on the tabular grain surfaces by adsorption of a photographically useful compound selected from among those that contain at least one divalent sulfur atom, thereby concurrently morphologically stabilizing the tabular grains and enhancing their photographic utility, and the released 2-hydroaminoazine is removed from the dispersing medium.

Abstract: A radiation sensitive emulsion is disclosed containing a silver halide grain population comprised of at least 50 mole percent chloride, based on silver, in which greater than 50 percent of the total grain projected area is accounted for by ultrathin tabular grains having a {111} crystal face stabilizer adsorbed to the major faces of the ultrathin tabular grains.

Abstract: A photographic emulsion is disclosed containing a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent. The coprecipitated grain population consists essentially of tabular grains which are at least 50 mole percent bromide, based on silver, and which have a mean thickness in the range of from 0.080 to 0.3 .mu.m, and a mean tabularity of greater than 8.

Abstract: A radiographic element is disclosed comprised of a transparent film support and spectrally sensitized tabular grain silver halide emulsion layer units coated on opposite sides of the film support. At least one of the emulsion layer units is comprised of tabular grains having a thickness of less than 0.2 micrometer accounting for greater than 50 percent of total grain projected area and exhibiting an average tabularity of greater than 25. Adsorbed to the surface of the tabular grains is at least one benzimidazolocarbocyanine dye chosen for its high level of absorption in the mid-green spectral region at the emission line of gadolinium oxysulfide, terbium activated intensifying screens and its low residual stain in the fully processed film.

Abstract: A process of forming on a substrate a coating of a precursor of a crystalline rear earth alkaline earth copper oxide or heavy pnictide mixed alkaline earth copper oxide electrical conductor and converting the precursor to the crystalline electrical conductor.

Abstract: A process of preparing a radiation sensitive high chloride high aspect ratio tabular grain emulsion is disclosed wherein silver ion is introduced into a gelatino-peptizer dispersing medium containing a stoichiometric excess of chloride ions with respect to the silver ions further characterized by a chloride ion concentration of less than 0.5 molar, a pH of at least 4.6, and a triaminopyrimidine grain growth modifier containing mutually independent 4, 5 and 6 ring position amino substituents, the 4 and 6 ring position substituents being hydroamino substituents.

Abstract: A process of preparing a radiation sensitive high chloride high aspect ratio tabular grain emulsion is disclosed wherein silver ion is introduced into a gelatino-peptizer dispersing medium containing a stoichiometric excess of chloride ions with respect to the silver ions further characterized by a chloride ion concentration of less than 0.5 molar, a pH of at least 4.6, and a grain growth modifier of the formula: ##STR1## where N.sup.4 is an amino moiety andZ represents the atoms completing a 5 or 6 member ring.

Abstract: A process of preparing a radiation sensitive high chloride high aspect ratio tabular grain emulsion is disclosed wherein silver ion is introduced into a gelatino-peptizer dispersing medium containing a stoichiometric excess of chloride ions a chloride ion concentration of less than 0.5 molar and a grain growth modifier of the formula: ##STR1## where Z.sup.2 is --C(R.sup.2).dbd. or --N.dbd.;Z.sup.3 is --C(R.sup.3).dbd. or --N.dbd.;Z.sup.4 is --C(R.sup.4).dbd. or --N.dbd.;Z.sup.5 is --C(R.sup.5).dbd. or --N.dbd.;Z.sup.6 is --C(R.sup.6).dbd. or --N.dbd.;with the proviso that no more than one of Z.sup.4, Z.sup.5 and Z.sup.6 is --N.dbd.;R.sup.2 is H, NH.sub.2 or CH.sub.3 ;R.sup.3, and R.sup.4 and R.sup.5 are independently selected, R.sup.3 and R.sup.5 being hydrogen, hydroxy, halogen, amino or hydrocarbon and R.sup.4 being hydrogen, halogen or hydrocarbon, each hydrocarbon moiety containing from 1 to 7 carbon atoms; andR.sup.6 is H or NH.sub.2.

Abstract: A process of preparing a radiation sensitive high chloride high aspect ratio tabular grain emulsion is disclosed wherein silver ion is introduced into a gelatino-peptizer dispersing medium containing a stoichiometric excess of chloride ions with respect to the silver ions further characterized by a chloride ion concentration of less than 0.5 molar and a grain growth modifier of the formula: ##STR1## where Z.sup.8 is --C(R.sup.8).dbd. or --N.dbd.;R.sup.8 is H, NH.sub.2 or CH.sub.3 ; andR.sup.1 is hydrogen or a hydrocarbon of from 1 to 7 carbon atoms.

Abstract: A process is disclosed of preparing a high chloride tabular grain emulsion for photographic use. An emulsion comprised of silver halide grains and a gelatino-peptizer dispersing medium in which morphologically unstable tabular grains having {111} major faces account for greater than 50 percent of total grain projected area and contain at least 50 mole percent chloride, based on silver, is formed in the presence of at least one 2-hydroaminoazine or xanthinoid morphological stabilizer adsorbed to surfaces of the tabular grains. Chemical sensitization of the emulsion and protonation of the morphological stabilizer are performed at least in part concurrently. Termination of protonation of the morphological stabilizer retains a portion of the morphological stabilizer on the surfaces of the chemically sensitized tabular grains.

Abstract: A process is disclosed of preparing an emulsion for photographic use comprising forming in the presence of an xanthinoid grain growth modifier an emulsion comprised of silver halide grains and a gelatino-peptizer dispersing medium in which morphologically unstable tabular grains having {111} major faces account for greater than 50 percent of total grain projected area and contain at least 50 mole percent chloride, based on silver. After the emulsion is formed, the pH of the emulsion is lowered to inactivate xanthinoid grain growth modifier, and the inactivated xanthinoid is replaced on the tabular grain surfaces by adsorption of a photographically useful compound chosen to contain at least one divalent sulfur atom, thereby concurrently morphologically stabilizing the tabular grains and enhancing their photographic utility.