High-speed high quality direct radiographic film
AssigneeEastman Kodak Company
InventorsAnthony Adin, Richard E. Beal, Franklin C. Brayer, Catherine C. Wideman
Life of this patent
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Abstract
A high quality direct radiographic film is useful for dental care. The film contains relatively high silver coverage preferably coated on both sides of the support. It also contains sufficient silver halide desensitizer to reduce silver halide sensitivity to X-radiation by at least 0.02 log E. The combination of silver and desensitizer coverages provides sufficiently high photographic speed, excellent image quality and increased stability to background radiation sources.
Claims22
A direct radiographic film comprising a support and having disposed on at least one side thereof, a silver halide emulsion unit,
- the silver coverage in said silver halide emulsion unit being at least 7 g/m2 and said silver halide emulsion unit comprises silver halide grains that are sensitive to X-radiation and have at least 80 mol % bromide (based on total silver), no more than 3 mol % iodide (based on total silver), and a mean equivalent circular diameter of at least 0.8 μm, said silver halide emulsion unit further comprising a silver halide desensitizer in an amount sufficient to reduce sensitivity of said silver halide grains to X-radiation by from about 0.02 log E to about 0.05 log E.
A direct radiographic film comprising a light transmissive support and having disposed on each side thereof, a silver halide emulsion unit,
- the silver coverage in each silver halide emulsion unit being from about 8 to about 11 g/m2 and each silver halide emulsion unit comprises tabular silver halide grains having at least 98 mol % bromide (based on total silver), no more than 2 mol % iodide (based on total silver), and a mean equivalent circular diameter of from about 1 to about 3 μm,
- each silver halide emulsion unit further comprising one or more silver halide emulsion layers, at least one of said silver halide emulsion layers comprising as a silver halide desensitizer, 6-ethoxy-1-methyl-2-[2-(3-nitrophenyl)ethenyl]-quinolinium methyl sulfate, that is present in an amount sufficient to reduce sensitivity of said silver halide grains to X-radiation by from about 0.02 log E to about 0.05 log E,
- said film further comprising an overcoat disposed on each silver halide emulsion unit,
- said film also comprising in either or both said overcoats or a silver halide emulsion layer in each silver halide emulsion unit, a non-bleachable tinting dye,
- said film exhibiting fog growth of less than 0.18 (±0.04) upon exposure to 200 mR of either Co60 or Ir192 radiation.
Dependencies are inferred from the claim text.