摘要:
An element is disclosed containing a photothermographic layer capable of providing a retained viewable image when imagewise exposed and heated. The Layer contains a high chloride {100} tabular grains.
摘要:
A dual-coated radiographic element capable of producing a viewable image when heated following imagewise exposure is disclosed comprised of, on opposite sides of a transparent film, layer units containing radiation-sensitive radiation-sensitive silver halide grains, a light-insensitive source of silver, and a reducing agent for said light-insensitive reducible source of silver. Greater than 50 percent of total projected area of said silver halide grains being provided by tabular grains (a) having {100} major faces, (b) containing greater than 70 mole percent chloride, based on silver, (c) exhibiting an average thickness of less than 0.3 .mu.m, and (d) exhibiting an average equivalent circular diameter of greater than 0.6 .mu.m.
摘要:
A process of preparing a photothermographic composition of enhanced photosensitivity is disclosed comprised of (a) precipitating light-sensitive silver halide grains in the presence of a non-aqueous polymeric peptizer and (b) then combining the silver halide grains with an oxidation-reduction image-forming combination comprised of an organic silver compound and a reducing agent for the silver organic compound. Light-sensitivity of the silver halide grains is enhanced by, prior to step (b), sensitizing the silver halide grains with a gold sensitizer dissolved in an aqueous medium.
摘要:
A photothermographic composition of enhanced photosensitivity is disclosed prepared by a process of (a) precipitating light-sensitive silver halide grains in the presence of a non-aqueous polymeric peptizer and (b) then combining the silver halide grains with a non-aqueous polymeric vehicle containing an oxidation-reduction image-forming combination comprised of an organic silver compound and a reducing agent for the organic silver compound. Light-sensitivity of the silver halide grains is enhanced by, prior to step (b), sensitizing the silver halide grains with a 1,1,3,3-tetra-substituted thiourea or selenourea having an acid dissociation constant of less than 7.0, the thiourea or selenourea being dissolved in an aqueous medium.
摘要:
Spectrally sensitized tabular grain emulsions are disclosed exhibiting increased speeds and speed-granularity relationships superior to those of conventional emulsions of the same average grain sizes. The tabular grains have {111} major faces, contain greater than 70 mole percent bromide and from 0.25 to 10 mole percent iodide, based on silver, exhibit an average aspect ratio of greater than 50 and an average equivalent circular diameter of >10 micrometers, account for greater than 90 percent of total grain projected area, and have latent image forming chemical sensitization sites on their surfaces including epitaxially deposited silver halide protrusions of a face centered cubic rock salt crystal lattice structure forming epitaxial junctions with the tabular grains. The protrusions are restricted to those portions of the tabular grains (a) located nearest peripheral edges of and (b) accounting for less than 50 percent of the {111} major faces of the tabular grains, contain a silver chloride concentration at least 10 mole percent higher than that of the tabular grains, and include a higher iodide concentration than those portions of the tabular grains extending between the {111} major faces and forming epitaxial junctions with the protrusions.
摘要:
Spectrally sensitized tabular grain emulsions are disclosed exhibiting (1) increased speeds and (2) contrasts and speed-granularity relationships superior to those of conventional emulsions of the same average grain sizes. The tabular grains have {111} major faces, contain greater than 80 mole percent bromide, based on silver, and are substantially free of iodide, exhibit an average aspect ratio of greater than 50 and an average equivalent circular diameter of >10 micrometers, account for greater than 90 percent of total grain projected area, and have latent image forming chemical sensitization sites on their surfaces including epitaxially deposited silver halide protrusions of a face centered cubic rock salt crystal lattice structure forming epitaxial junctions with the tabular grains. The protrusions are restricted to those portions of the tabular grains (a) located nearest peripheral edges of and (b) accounting for less than 50 percent of the {111} major faces of the tabular grains. The protrusions contain silver iodide and a silver chloride concentration at least 10 mole percent higher than that of the tabular grains.
摘要:
A radiation-sensitive high bromide {111} tabular grain emulsion is disclosed in which at least 90 percent of silver halide epitaxy of an isomorphic face centered cubic crystal lattice structure containing at least 1 mole percent iodide is deposited on the {111} major faces in the form of monocrystalline terraces. Each epitaxial terrace is grown from a nucleation site along an edge of a {111} major face inwardly, with terraces overlying less than 25 percent of the {111} major faces. Surprisingly, these emulsions exhibit higher photographic speeds than those produced by growing silver halide epitaxy outwardly as protrusions from the corners or edges of the tabular grains.
摘要:
A radiation-sensitive spectrally sensitized tabular grain emulsion is disclosed which exhibits improved speed and contrast. The tabular grains have {111} major faces, contain greater than 70 mole percent bromide and up to 10 mole percent iodide, based on silver, account for greater than 90 percent of total grain projected area, and have an average equivalent circular diameter of at least 3.5 .mu.m. The tabular grains have latent image forming chemical sensitization sites on their surfaces including epitaxially deposited silver halide protrusions of a face centered cubic rock salt crystal lattice structure forming epitaxial junctions with the tabular grains. The protrusions are restricted to those portions of the tabular grains located nearest peripheral edges of and accounting for less than 10 percent of the {111} major faces of the tabular grains, accounting for less than 5 percent of total silver forming the tabular grains and protrusions, containing a silver chloride concentration at least 10 mole percent higher than that of the tabular grains, and contain at least 1 mole percent iodide, based on silver in the protrusions.
摘要:
A camera-speed color photothermographic imaging method is disclosed. A photothermographic film is employed that contains a photographically responsive, thermally developable panchromatically sensitized emulsion layer unit capable of concurrently forming silver and dye image densities. The emulsion layer unit is exposed in three separate image capture areas to blue, green or red light received from the photographic subject to create latent images of blue, green and red light exposure. The photothermographic element is thermally processed to produce images of the same hue in each of the three separate image capture areas. The images of blue, green and red light exposures are then converted into a corresponding additive or subtractive primary hue, and integrated to provide a positive or negative color image of the photographic subject.
摘要:
A camera-speed color photothermographic imaging method is disclosed. A photothermographic film is employed that contains a photographically responsive, thermally developable panchromatically sensitized emulsion layer unit capable of concurrently forming silver and dye image densities. The emulsion layer unit is exposed in three separate image capture areas to blue, green or red light received from the photographic subject to create latent images of blue, green and red light exposure. The photothermographic element is thermally processed to produce images of the same hue in each of the three separate image capture areas. The images of blue, green and red light exposures are then converted into a corresponding additive or subtractive primary hue, and integrated to provide a positive or negative color image of the photographic subject.