Claims
- 1. A direct X-ray system comprised of(1) a black-and-white negative-working radiographic film material, comprised of a transparent support coated on at least one side thereof with a tabular grain emulsion layer, substantially free from spectrally sensitizing dyes, in which at least 50 percent of total grain projected area of all grains is accounted for by silver bromoiodide tabular grains having an iodide content of less than 5 mole %, based on silver, having an average aspect ratio of at least 2, and having a volume greater than 0.03 μm3, further characterized in that said tabular grain emulsion layer(s) comprise(s), in an amount of from 5 mg up to 100 mg per mole of coated silver bromoiodide at least one desensitizing agent having a hetero-aromatic part and an electron-withdrawing group; and (2) disposed on opposite sides of the radiographic element, two intensifying screen sheets selected from the group consisting of lead, lead oxide, copper and steel, said screen sheets designed to emit electrons when exposed to X- or γ-rays with an energy greater than or equal to 10 kVp.
- 2. System according to claim 1, wherein in the film material said hetero-aromatic part in said desensitizing agent is selected from the group consisting of benzo-selenazole; benzo-thiazole; 1-cyclo-hexylpyrrole; 1,2-diaryl-indole; pyrrolo-[2,3-b]pyrazine; pyrrolo[2,3-b]pyridine; pyrrolo[2,3-b]quinoxaline; imidazo[4,5-b]quinoxaline; imidazo[1,2-b]pyridazine; quinolinium; imidazo[2,1-b]-1,3,4-thiadiazole; imidazo[2,1-b]-thiazole; imidazo[1,2-a]pyridine; arylindole; azacyanines, 2-amino-4-aryl-5-thiazole; thiapyrylium; benzopyrylium; pyrylium; 2-heterocyclylindole; 2-aryl-1,8-trimethyleneindole; carbazole; 2-aryl-1-alkylindole; 5-mercapto-tetrazole, indazole, piazine, thiuram disulfide, nitron, phenozine-N-oxides and N,N′-dialkyl-4,4′-bispyridinium.
- 3. System according to claim 1, wherein said electron withdrawing group or substituent is selected from the type consisting of acetyl-, benzosulfonyl-, benzoyl-, carbonyl-, acetoxy-, cyano-, nitro-, hydroxy-, chloro- and sulfonyl-.
- 4. System according to claim 1, wherein said silver bromoiodide tabular grains have silver iodide in an amount of at most 1 mole %, based on silver.
- 5. System according to claim 1, wherein said tabular grains have an average volume between 0.05 and 2 μm3 and the aspect ratio is between 5 and 25.
- 6. System according to claim 1, wherein a silver content per coated side, expressed as an equivalent amount of silver nitrate, is from 5 up to 25 g/m2.
- 7. Method for forming a radiographic image, comprising the steps of(1) exposing a system according to claim 1 to x- or γ-rays with an energy greater than or equal to 10 kVp in order to form a latent image in radiation-sensitive layers of the film material, and (2) developing the said latent image.
- 8. Method according to claim 7, wherein the step of developing the said latent image is performed in a developing bath containing ascorbic acid as a developing agent.
- 9. Method according to claim 7, said method comprising the steps of(1) exposing a system according to claim 1, wherein said radiographic material is fully forehardened, and (2) developing the latent image obtained by exposure in a developing bath without further hardening.
- 10. Method according to claim 8, said method comprising the steps of(1) exposing a system according to claim 1, wherein said radiographic material is fully forehardened, and (2) developing the latent image obtained by exposure in a developing bath without further hardening.
- 11. A personal electromagnetic radiation monitor wearable by a person in order to warn the person of a radiation hazard condition caused by electromagnetic radiation emanating from a source of electromagnetic radiation, said monitor essentially comprising a material used in the system of claim 1.
Priority Claims (1)
Number |
Date |
Country |
Kind |
00203440 |
Oct 2000 |
EP |
|
Parent Case Info
This application claims the benefit of Provisional Application No. 60/245,289, filed Nov. 2, 2000.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
5900357 |
Feumi-Jantou |
May 1999 |
A |
5952163 |
Baugher et al. |
Sep 1999 |
A |
5965337 |
Drain et al. |
Oct 1999 |
A |
Provisional Applications (1)
|
Number |
Date |
Country |
|
60/245289 |
Nov 2000 |
US |