Radiographic elements exhibiting reduced crossover

Claim 2

In a radiographic element comprised of first and second imaging means, at least said first imaging means including a silver halide emulsion comprised of a dispersing medium and radiation-sensitive silver halide grains, and a support interposed between said imaging means capable of transmitting radiation to which said second imaging means is responsive the improvement comprising said first imaging means containing tabular silver halide grains having a thickness of less than 0.3 micron, a diameter of at least 0.6 micron, and an average aspect ratio of greater than 8:1 accounting for at least 50 percent of the total projected area of said silver halide grains present in said silver halide emulsion and spectral sensitizing dye adsorbed to the surface of said tabular silver halide grains in an amount sufficient to substantially optimally sensitize said tabular grains.

Claim 3

An improved radiographic element according to claim 1 wherein said support is a film support.

Claim 4

An improved radiographic element according to claim 1 wherein said support is a blue tinted transparent film support.

Claim 5

An improved radiographic element according to claim 1 wherein said tabular silver halide grains have an average aspect ratio of at least 12:1.

Claim 6

An improved radiographic element according to claim 1 wherein said tabular silver halide grains account for at least 70 percent of the total projected area of said silver halide grains.

Claim 7

An improved radiographic element according to claim 1 wherein said dispersing medium is comprised of a hardenable hydrophilic colloid.

Claim 8

An improved radiographic element according to claim 1 wherein said silver halide is silver bromide or silver bromoiodide.

Claim 9

An improved radiographic element according to claim 1 wherein said spectral sensitizing dye exhibits a shift in hue as a function of adsorption.

Claim 10

An improved radiographic element according to claim 8 wherein said spectral sensitizing dye is a cyanine dye.

Claim 11

In a radiographic element comprised of first and second silver halide emulsion layers each comprised of a dispersing medium and radiation-sensitive silver bromide or silver bromoiodide grains and a film support interposed between said emulsion layers capable of transmitting radiation to which said emulsion layers are responsive, the improvement comprising said emulsion layer containing substantially optimally chemically sensitized tabular silver bromide or silver bromoiodide grains having a thickness of less than 0.3 micron, a diameter of at least 0.6 micron, and an average aspect ratio of at least 12:1 accounting for at least 70 percent of the total projected area of said silver bromide or silver bromoiodide grains present in said silver halide emulsion layer and spectral sensitizing dye which exhibits a shift in hue as a function of adsorption being adsorbed to the surface of said tabular silver bromide or silver bromoiodide grains in an amount sufficient to substantially optimally sensitize said tabular grains.

Claim 12

In a radiographic element comprised of first and second silver halide emulsion layers each comprised of a dispersing medium and radiation-sensitive silver bromide or silver bromoiodide grains and a film support interposed between said emulsion layers capable of transmitting radiation to which said emulsion layers are responsive, the improvement comprising said emulsion layer containing substantially optimally chemically sensitized tabular silver bromide or silver bromoiodide grains having a thickness of less than 0.3 micron, a diameter of at least 0.6 micron, and an average aspect ratio of at least 12:1 accounting for at least 70 percent of the total projected area of said silver bromide or silver bromoiodide grains present in said silver halide emulsion layer and spectral sensitizing dye which exhibits a shift in hue as a function of adsorption being adsorbed to the surface of said tabular silver bromide or silver bromoiodide grains in an amount sufficient to substantially optimally sensitize said tabular grains.

Claim 13

An improved radiographic element according to claim 10 wherein said dispersing medium is gelatin or a gelatin derivative.

Claim 14

An improved radiographic element according to claim 10 wherein said tabular grains have an average aspect ratio of at least 12:1.

Claim 15

An improved radiographic element according to claim 10 wherein said tabular grains have an average aspect ratio of from 20:1 to 100:1.

Claim 16

An improved radiographic element according to claim 10 wherein said sensitizing dye is a cyanine dye exhibiting a bathochromic shift in hue as a function of adsorption.

Claim 17

An improved radiographic element according to claim 14 wherein said cyanine dye contains at least one nucleus chosen from the group consisting of quinolinium, benzoxazolium, benzothiazolium, benzoselenazolium, benzimidazolium, naphthooxazolium, naphthothiazolium, and naphthoselenazolium nuclei.

Claim 18

An improved radiographic element according to claim 15 wherein said cyanine dye is a carbocyanine dye.

Claim 19

An improved radiographic element according to claim 10 wherein said sensitizing dye is present in a concentration of from about 25 to 100 mole percent of monolayer coverage of the surface of said silver bromide or bromoiodide grains.

Claim 20

An improved radiographic element according to claim 10 wherein said spectral sensitizing dye is a green spectral sensitizing dye.

Claim 21

In a radiographic element comprised of first and second silver halide emulsion layers each comprised of a dispersing medium and radiation-sensitive silver bromide or silver bromoiodide grains and a film support interposed between said emulsion layers capable of transmitting radiation to which said emulsion layers are responsive, the improvement comprising said emulsion layers containing substantially optimally chemically sensitized tabular silver bromide or silver bromoiodide grains having a thickness of less than 0.5 micron, a diameter of at least 0.6 micron, and an average aspect ratio of greater than 8:1 accounting for at least 50 percent of the total projected area of said silver bromide or silver bromoiodide grains present in said silver halide emulsion layers and blue spectral sensitizing dye which exhibits a shift in hue as a function of adsorption being adsorbed to the surface of said tabular silver bromide or silver bromoiodide grains in an amount sufficient to substantially optimally sensitize said tabular grains.

Claim 22

In a radiographic element comprised of first and second silver halide emulsion layers each comprised of a dispersing medium and radiation-sensitive silver bromide or silver bromoiodide grains and a film support interposed between said emulsion layers capable of transmitting radiation to which said emulsion layers are responsive, the improvement comprising said emulsion layers containing substantially optimally chemically sensitized tabular silver bromide or silver bromoiodide grains having a thickness of less than 0.5 micron, a diameter of at least 0.6 micron, and an average aspect ratio of greater than 8:1 accounting for at least 50 percent of the total projected area of said silver bromide or silver bromoiodide grains present in said silver halide emulsion layers and blue spectral sensitizing dye which exhibits a shift in hue as a function of adsorption being adsorbed to the surface of said tabular silver bromide or silver bromoiodide grains in an amount sufficient to substantially optimally sensitize said tabular grains.

Claim 23

An improved radiographic element according to claim 19 wherein said tabular grains have an average aspect ratio of at least 12:1 and account for at least 70 percent of the total projected area of said silver bromide or silver bromoiodide grains.