Low silver radiographic film with improved visual appearance
AssigneeEastman Kodak Company
InventorRobert E. Dickerson
Life of this patent
Estimating the term…
Abstract
Radiographic films exhibit improved visual performance because of the presence of certain colorants that provide more positive a* values without diminishing image tone (b*). Thus, the greenish tint the films may exhibit is reduced. These films provide desired sensitometric properties while they have reduced silver, hydrophilic polymer binder, and hardener coverage on both sides of a transparent support.
Claims20
A radiographic silver halide film comprising a transparent support, said film having disposed on each side of said support, one or more hydrophilic colloid layers including at least one silver halide emulsion layer,
- each of said silver halide emulsion layers comprising silver halide tabular grains that (a) have the same or different composition in each silver halide emulsion layer, (b) account for at least 50% of the total grain projected area within each silver halide emulsion layer, and (c) have an average aspect ratio of greater than 5,
- the silver coverage on each side of said support being from about 10 to about 14 mg/dm2,
- each silver halide emulsion layer comprising one or more hydrophilic polymer vehicles at a total coverage of from about 7 to about 20 mg/dm2,
- the level of hardener on each side of said support being from about 0.3 to about 1 weight % based on total polymer vehicles on that side,
- said radiographic silver halide film further comprising in one or more of said silver halide emulsion layers, a colorant that is present in an amount sufficient to provide a film a* value of from about −3.2 to about −2.0 at a film b* value of −7.
The film of claim r that exhibits a film a* value greater than or equal to −5.5 at Dmin.
A radiographic silver halide film comprising a transparent polymeric support, said film having disposed on each side of said support, two or three hydrophilic colloid layers including a single silver halide emulsion layer on each side of said support,
- each of said silver halide emulsion layers comprising silver halide tabular grains that (a) have the same or different composition in each silver halide emulsion layer, (b) account for at least 80% of the total grain projected area within each silver halide emulsion layer, and (c) have an average aspect ratio of greater than 8, each silver halide emulsion layer being composed of silver halide grains comprising at least 98 mol % bromide and up to 1.5 mol % iodide, both based on total silver,
- the silver coverage on each side of said support being from about 11 to about 13 mg/dm2,
- each silver halide emulsion layer comprising one or more hydrophilic polymer vehicles at a total coverage of from about 7 to about 15 mg/dm2,
- the level of hardener on each side of said support being from about 0.3 to about 0.8 weight % based on total polymer vehicles on that side,
- said radiographic silver halide film further comprising in one or more of said silver halide emulsion layers, a colorant that is present in an amount sufficient to provide a film a* value of from about −3.0 to about −2.4 at a film b* value of −7, and a film a* value greater than or equal to −5.5 at Dmin.
Dependencies are inferred from the claim text.