EP0794456B1 - Procédé de reproduction d'une image médicale mémorisée électroniquement sur matériau photographique sensible à la lumière - Google Patents

Procédé de reproduction d'une image médicale mémorisée électroniquement sur matériau photographique sensible à la lumière Download PDF

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Publication number
EP0794456B1
EP0794456B1 EP97200589A EP97200589A EP0794456B1 EP 0794456 B1 EP0794456 B1 EP 0794456B1 EP 97200589 A EP97200589 A EP 97200589A EP 97200589 A EP97200589 A EP 97200589A EP 0794456 B1 EP0794456 B1 EP 0794456B1
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Prior art keywords
emulsion
silver
crystals
hardcopy
substituted
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German (de)
English (en)
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EP0794456A1 (fr
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Hieronymus c/o Agfa-Gevaert N.V. Andriessen
Freddy c/o Agfa-Gevaert N.V. Henderickx
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Agfa Gevaert NV
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Agfa Gevaert NV
Agfa Gevaert AG
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Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/035—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein characterised by the crystal form or composition, e.g. mixed grain
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
    • G03C5/26—Processes using silver-salt-containing photosensitive materials or agents therefor
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/08—Sensitivity-increasing substances
    • G03C1/09—Noble metals or mercury; Salts or compounds thereof; Sulfur, selenium or tellurium, or compounds thereof, e.g. for chemical sensitising
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/035—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein characterised by the crystal form or composition, e.g. mixed grain
    • G03C2001/03541—Cubic grains
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/035—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein characterised by the crystal form or composition, e.g. mixed grain
    • G03C2001/03594—Size of the grains
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/08—Sensitivity-increasing substances
    • G03C1/09—Noble metals or mercury; Salts or compounds thereof; Sulfur, selenium or tellurium, or compounds thereof, e.g. for chemical sensitising
    • G03C2001/093—Iridium
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C1/00—Photosensitive materials
    • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
    • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
    • G03C1/08—Sensitivity-increasing substances
    • G03C1/09—Noble metals or mercury; Salts or compounds thereof; Sulfur, selenium or tellurium, or compounds thereof, e.g. for chemical sensitising
    • G03C2001/097—Selenium
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C2200/00—Details
    • G03C2200/39—Laser exposure
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C2200/00—Details
    • G03C2200/52—Rapid processing
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
    • G03C5/16—X-ray, infrared, or ultraviolet ray processes
    • G03C5/164—Infra-red processes

Definitions

  • This invention relates to a method of reproducing an electronically stored medical image on a hardcopy material.
  • a laser imager is a digital system containing a high performance digital computer offering more advantages. Instead of just printing the images, the incoming images can be stored temporarily in an electronic memory and the data as well as the lay-out of the images can be manipulated before actually being printed on a film.
  • This electronic memory offers the possibility to buffer the incoming data from several diagnostic modalities by means of an image network, which is a real advantage in comparison with e.g. CRT imaging wherein the hard copy is exposed image by image. In that case, while one examination is taking place, the imager is unavailable for others and as a result, each diagnostic unit requires a separate CRT imager.
  • the photographic hardcopy material used in the laser imagers, combines an excellent image quality with the appropriate physical properties, necessary for an error free filmhandling by the imager.
  • image quality the photographic material preferably has high sharpness, a good image tone (color hue) of the developed silver, preferably a purely black image, a preferred gloss level, and appropriate contrast values to allow a high maximum density and crisp alfanumerics.
  • the access time of the laser hardcopy material should be as short as possible.
  • Factors responsible for delayed rates at which the process proceeds may be the exposure time of the film by the laser, the transport time before exposure to the system and after exposure to an automatic processor, and the processing time, dry-to-dry, of the hardcopy material.
  • the exposure time and transport time are dependent on specific features of the laser source, the mechanical construction of the system and the dimensions of the hardcopy material
  • the processing time is especially determined by the film characteristics (sensitivity, also called "speed") and the chemicals used in the processing cycle.
  • Typical modern processors have dry-to-dry cycles of less than 60 seconds, more preferable less than or equal to 50 seconds.
  • Hardener free chemistry offers higher convenience with respect to ecology, manipulation and regeneration of chemicals in the automatic processor provided that the hardcopy material has the expected sensitometric results as e.g. sensitivity, gradation and maximum density within restricted processing time limits.
  • the hardening agent reduces the drying time in the automatic processor by crosslinking the gelatin chains of the photographic material, thereby reducing the water adsorption of said material. Therefore, a photographic material suited for hardener free processing should be forehardened during emulsion coating in order to allow a short dry-to-dry processing cycle.
  • flat tabular grains are preferred for a photographic material intended for hardener free processing of direct exposure X-ray images and for hardcopy images, generated by means of CRT printers. Indeed, it is well known that flat tabular grains combine a high speed with a large covering power (density vs. developed silver), even at high hardening degrees. This is in favour of coating amounts of silver halide crystals which can be reduced to a remarkable extent, further providing an ecological advantage in that lower amounts of chemicals are required and less regeneration amounts.
  • a method of reproducing an electronically stored medical image on a hardcopy material comprising a support and on only one side thereof a silver halide emulsion layer and a hydrophilic colloid layer, wherein said emulsion layer comprises red sensitised homogeneous cubic silver chloride, silver chloroiodide, silver chlorobromide or silver chlorobromoiodide crystals having not less than 70 mole % of chloride ions and preferably not less than 90 mole %; not more than 1 mole % of iodide ions and an average crystal size of from 0.12 to 0.30 ⁇ m and more preferred from 0.15 to 0.25 ⁇ m; wherein said crystals are coated in an amount, expressed as an equivalent amount of silver nitrate of from 2 to 6 g per sq.m., and wherein said material has a hardening degree corresponding with a water absorption of up to 3 g per gram of gelatin at an emulsion side, the
  • a method showing high convenience for the reproduction of a medical, electronically stored image on the silver halide light-sensitive hardcopy material disclosed hereinbefore comprising the steps of exposing said hardcopy material with a red or infrared laser source within a time of less than or equal to 10 s for a size format of 35.56 cm x 43.18 cm (14"x17"); transporting said hardcopy material to an automatic processor within a time of less than or equal to 5 s; processing dry-to-dry said hardcopy material in said automatic processor proceeding within a time of from 30 to less than 50 s making use of developer and fixer solutions without hardening agent.
  • this method it is capable to provide in a time interval of one minute at least 4 consecutive sheets with a size format of 35.56 cm x 43.18 cm (17"x14") of the said silver halide light-sensitive hardcopy material of medical, electronically stored images.
  • the hardcopy material used in the image formation method according to the present invention is particularly useful for the reproduction of electronically stored medical images by means of a laser recorder.
  • Said hardcopy material essentially is a photographic material comprising silver chloride, silver chloroiodide, silver chlorobromide and/or silver chlorobromoiodide emulsions coated on a support in at least one emulsion layer on one side of said support.
  • an emulsion layer of said material comprises relatively small cubic silver chloride, silver chloroiodide, silver chlorobromide and/or silver chlorobromoiodide crystals, further referred to as "cubic crystals rich in chloride", having a crystal size from 0.12 to 0.30 ⁇ m, and more preferably from 0.15 to 0.25 ⁇ m sufficient speed was attained without deterioration of image tone, in that a shift to brown coloured silver after development was observed.
  • the said emulsions rich in silver chloride have crystals or grains having a monodisperse grain size distribution.
  • Said size distribution is called "monodisperse" when 95% of the grains have a size that does not deviate more than 30 % from the average grain size, and more preferably not more than 20 %.
  • Cubic crystals are especially preferred as they allow rapid processing. In principle the same should be possible with flat tabular crystals but, even if methods are applied that reveal a more homogeneous silver halide distribution, it is difficult to get small tabular crystals offering a suitable sensitivity. Moreover due to the light-reflection of the developed silver from said tabular grains which is situated at longer wavelengths the image tone is not neutral but shifted to a unacceptable reddish brown colour.
  • the emulsions containing cubic crystals rich in chloride coated in the emulsion layer(s) of the hardcopy material used in the image-forming method according to this invention may be prepared by mixing the halide (chloride being in excess versus bromide and/or iodide, if present) and silver salt solutions in partially or fully controlled conditions of temperature, concentrations, sequence of addition, and rates of addition.
  • the silver halide is preferably precipitated according to the double-jet method, in the presence of a colloid binder in a temperature controlled vessel provided with a solution inlet and stirring unit.
  • a preferred precipitation technique is the double-jet method, wherein the silver ion concentration is controlled during the precipitation and wherein the flow rate of the reacting solutions is enhanced as the precipitation proceeds, at such a rate that no renucleation appears.
  • This method offers the possiblity to get well-defined crystals having a regular cubic habit within a short precipitation time.
  • Preferred cubic crystals rich in chloride have a crystal size between 0.12 and 0.30 ⁇ m, more preferably between 0.15 and 0.25 ⁇ m and even more preferably between 0.20 and 0.25 ⁇ m.
  • a suitable black image tone of the silver generated after developing cubic crystals having up to at most 30 mole % and more preferred up to at most 10 mole % of silver bromide and/or up to at most 1 mole % of iodide is obtained as well as a high covering power of the developed grains.
  • Colloidal binders used during precipitation of the cubic crystals rich in silver chloride are hydrophilic binders such as the frequently used gelatin.
  • Gelatin may, however, be replaced in part by synthetic, semi-synthetic, or natural polymers.
  • Synthetic substitutes for gelatin are e.g. polyvinyl alcohol, poly-N-vinyl pyrrolidone, polyvinyl imidazole, polyvinyl pyrazole, polyacrylamide, polyacrylic acid, and derivatives thereof, in particular copolymers thereof.
  • Natural substitutes for gelatin are e.g. other proteins such as zein, albumin and casein, cellulose, saccharides, starch, and alginates.
  • the semi-synthetic substitutes for gelatin are modified natural products e.g. gelatin derivatives obtained by conversion of gelatin with alkylating or acylating agents, by grafting of polymerisable monomers on gelatin or prehardened gelatins with blocked functional groups as a consequence of this prehardening treatment, and cellulose derivatives such as hydroxyalkyl cellulose, carboxymethyl cellulose, phthaloyl cellulose, and cellulose sulphates.
  • modified natural products e.g. gelatin derivatives obtained by conversion of gelatin with alkylating or acylating agents, by grafting of polymerisable monomers on gelatin or prehardened gelatins with blocked functional groups as a consequence of this prehardening treatment
  • cellulose derivatives such as hydroxyalkyl cellulose, carboxymethyl cellulose, phthaloyl cellulose, and cellulose sulphates.
  • the binder should of course dispose of an acceptably high number of functional groups, which by reaction with an appropriate hardening agent can provide a sufficiently resistant layer.
  • functional groups are especially the amino groups, but also carboxylic groups, hydroxy groups, and active methylene groups.
  • Another substitute for gelatin may be silica as has been described in the published EP-A's 0 392 092, 0 517 961, 0 528 476, 0 649 051 and 0 704 749.
  • gelatin may be lime-treated or acid-treated.
  • the preparation of such gelatin types has been described in e.g. "The Science and Technology of Gelatin", edited by A.G. Ward and A. Courts, Academic Press 1977, page 295 and next pages.
  • the gelatin may also be an enzyme-treated gelatin as described in Bull. Soc. Sci. Phot. Japan, N° 16, page 30 (1966).
  • Preferably use is made of photographically inert gelatin in order to add a reproducible amount of chemical sensitisers at the end of the precipitation or after flocculation or washing or redispersing the emulsion rich in silver chloride. To get a qualitatively good flocculate flocculating agents as e.g.
  • polystyrene sulphonic acid, etc. may be added before or after acidifying the emulsion.
  • Other possibilities are offered by filtration techniques e.g. by dialysis, ultrafiltration etc. so that the emulsion may be washed to a desired pAg value without the requirement to be redispersed afterwards.
  • Emulsion flocculates need to be washed out by the addition of well-determined amounts of demineralised water, whether or not doped with small amounts of water-soluble salts like e.g. sodium or potassium chloride.
  • the light-sensitive emulsion rich in silver chloride coated in light-sensitive hydrophilic layers of the hardcopy material used in the image-forming method according to the present invention is preferably chemically sensitised in order to reach its required sensitivity as described e.g. in "Chimie et Physique Photographique” by P. Glafkides, in “Photographic Emulsion Chemistry” by G.F. Duffin, in “Making and Coating Photographic Emulsion” by V.L. Zelikman et al, and in "Die Grundlagen der Photographischen mit Silberhalogeniden” edited by H. Frieser and published by Akademische Verlagsgesellschaft (1968).
  • chemical sensitisation may be carried out by effecting the ripening in the presence of small amounts of compounds containing sulphur e.g. thiosulphate, thiocyanate, thioureas, sulphites, mercapto compounds, and rhodamines.
  • sulphur e.g. thiosulphate, thiocyanate, thioureas, sulphites, mercapto compounds, and rhodamines.
  • the emulsions may be sensitised also by means of gold-sulphur ripeners or by means of reductors e.g. tin compounds as described in GB-A 789,823, amines, hydrazine derivatives, formamidine-sulphinic acids, and silane compounds.
  • Preferred amounts of a preferred compound as e.g. potassium hexachloroiridate(III), added during chemical ripening are from 0.5 to 20 ⁇ mole per mole of silver and more preferred from 1 to 5 ⁇ mole per mole.
  • Suitable dopants used during precipitation or chemical ripening of the silver chloride or silver chlorobromide emulsion crystals may be Fe, Co, Ni, Ru, Rh, Pd, Os, Pt, Pb, Cd, Hg, Tl and Au.
  • One of these chemical sensitisation methods or a combination thereof may be used.
  • the silver halide crystals are predigested with weakly oxidising compounds as e.g. thiosulphonic acids before being chemically ripened.
  • weakly oxidising compounds as e.g. thiosulphonic acids
  • Chemical sensitisation may occur in the presence of spectral sensitisers.
  • the said spectral sensitisers have been chosen as a function of the gas or semiconductor laser source used, showing a high light absorption at the exposure wavelength of the said laser source.
  • Spectral sensitisers may be added partially before, partially after or integrally after chemical sensitisation with a total amount needed to reach the optimal coverage degree.
  • the light-sensitive cubic silver halide emulsions rich in chloride used in the image-forming method according to the present invention may be spectrally sensitised with methine dyes such as those described by F.M. Hamer in "The Cyanine Dyes and Related Compounds", 1964, John Wiley & Sons.
  • Dyes that may be used for the purpose of spectral sensitisation include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, homopolar cyanine dyes, hemicyanine dyes, styryl dyes and hemioxonol dyes.
  • Particularly preferred dyes are those absorbing in the red or infrared wavelength region of the wavelength spectrum, said dyes being selected from the group consisting of di-, tri-, tetra-, penta- and heptamethine cyanines and merocyanines, rhodacyanines and polynuclear merocyanines.
  • Especially suitable sensitising dyes in the red part of the visible spectrum are trimethinecyanines as described e.g. in US-A 3,282,933; in EP-A 0 467 370; in JP-A 05 040 324; in SU 01 645 270; in DE 01 028 718 and in GB 2,267,287.
  • Structures having a meso -S-CH 3 substitution therein have been described in US-A's 2,557,806 and 3,460,947 and in GB's 1,207,006 and 2,048,888.
  • Pentamethines absorbing more bathochromically are also very suitable and have been described in US-A's 3,615,632 and 3,669,672; in DE 03 216 568; in JP-A's 50 000 503; 53 142 223; 62 191 846; 62 194 252; 62 254 139; 62 262 853; 63 100 448 and 63 264 743 and in JP-B's 85 057 583; 92 064 060; 93 058 176; 93 060 093; 93 220 339 and 94 058 536. Dyes absorbing in the infrared region, are described e.g. in JP-A 02 071 257 and in Research Disclosure 00 289 052, May 1988, p. 301-303.
  • rhodacyanine dyes with chemical structures as described e.g. in EP-A 0 473 209 are the most preferred (see sensitising dye (1) in the Examples hereinafter) as well as heptamethine sensitising dye (2), also described in the Examples hereinafter.
  • Dimethine merocyanines useful as red light absorbing spectral sensitisers have been described in US-A's 3,625,698 and 4,461,828; in EP-Specification 0 127 455; in JP-A 61 281 235; in JP-B 76 041 055 and in DE's 01 028 718 and 02 330 602.
  • Tetramethine merocyanines also absorbing red light, have been described in US-A's 2,493,747; 2,497,876; 2,719,152; 2,947,631; 3,288,610; 3,385,707; 3,439,774; 3,519,430; 3,537,858; 3,567,458; 3,576,641; 3,579,348; 3,615,640; 3,642, 786; 3,660,102; 3,854,956; 2,719,152; 2,742,833; 3,519,430; 3,642,787; 3,658,522 and 4,113,496; in GB's 846,298; 1,078,227; 1,144,548 and 1,192,267; SU 01 126 572; 1,192,267; 1,582,132; 2,065,314 and 2,162,855; in DE's 02 207 352 and 02 451 158; in JP-A's 51 059 881; 51 123 223; 62 073
  • Suitable supersensitisers are e.g. heterocyclic mercapto compounds containing at least one electronegative substituent as described e.g. in US-A 3,457,078, nitrogen-containing heterocyclic ring-substituted aminostilbene compounds as described e.g. in US-A's 2,933,390 and 3,635,721; aromatic organic acid/formaldehyde condensation products as described e.g. in US-A 3,743,510, cadmium salts, and azaindene compounds.
  • the silver halide emulsion(s) coated in hardcopy materials used in the image-forming method according to the present invention may comprise compounds preventing the formation of fog or stabilising the photographic characteristics during the production or storage of photographic elements or during the photographic treatment thereof.
  • Many known compounds may be added as fog-inhibiting agent or stabiliser to the silver halide emulsion. Suitable examples are i.a.
  • heterocyclic nitrogen-containing compounds such as benzothiazolium salts, nitroimidazoles, nitrobenzimidazoles, chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, aminotriazoles, benzotriazoles (preferably 5-methyl-benzo-triazole), nitrobenzotriazoles, mercaptotetrazoles, in particular 1-phenyl-5-mercapto-tetrazole, mercaptopyrimidines, mercaptotriazines, benzothiazoline-2-thione, oxazoline-thione, triazaindenes, tetrazaindenes and pentazaindenes, especially those described by Birr in Z.
  • benzothiazolium salts such as benzothiazolium salts, nitroimidazoles, nitrobenzimidazoles,
  • triazolopyrimidines such as those described in GB-A 1,203,757, GB-A 1,209,146, JP-A 75-39537 and GB-A 1,500,278, and 7-hydroxy-s-tria-zolo-[1,5-a]-pyrimidines as described in US-Patent 4,727,017, and other compounds such as benzenethiosulphonic acid, benzenethiosulphinic acid, benzenethiosulphonic acid amide.
  • Other compounds that may be used as fog-inhibiting compounds are metal salts such as e.g. the compounds described in Research Disclosure N° 17643 (1978), Chaptre VI.
  • Preferred stabilisers added to the silver chloride, silver chloroiodide, silver chlorobromide or silver chlorobromoiodide emulsion coated in the emulsion layer(s) of the hardcopy material used in the method according to the present invention are e.g. 4-hydroxy-6-methyl-1,3,3a,7-tetraazaindene, 1-phenyl-5-mercaptotetrazole etc., thioether substituted 1-phenyl-5-mercaptotetrazoles as described in EP-A 0 053 851 being more preferable, especially if they have a solubilisable group as those described e.g. in Research Disclosure No. 24236 (1984).
  • Fog-inhibiting agents or stabilisers can be added to the silver halide emulsion prior to, during, or after the ripening thereof and mixtures of two or more of these compounds may be used.
  • a mixture of two or more emulsions from cubic crystals rich in chloride having the same or different crystal sizes, a different or the same chemical ripening treatment and/or a different or the same coverage degree with one or more spectral sensitisers being different from each other or the same, as those described hereinbefore may be added to at least one light-sensitive emulsion layer.
  • emulsion layer If more than one emulsion layer is coated onto one side of the support the same or different emulsions or emulsion mixtures may be present in the different layers. If the same emulsion or emulsion mixture is present in different emulsion layers it is a preferred embodiment to add distinct amounts of spectral sensitiser during chemical ripening and/or preparation for coating in order to get a broader exposure latitude for the material according to the image-forming method of the present invention and less sensitometric fluctuations in the processing of the hardcopy material.
  • a total amount of coated silver halide crystals rich in chloride, expressed as an equivalent amount of silver nitrate, is from 2 to 6 g/m 2 , and more preferably from 3 to 5 g/m 2 .
  • the total gelatin content at the emulsion side of from 1 to 3 g/m 2 .
  • antihalation dyes useful ingredients added to the emulsion layer(s), to an antihalation undercoat layer and/or to an antistress layer and/or to one or more backing layers are antihalation dyes, developing accelerators, plasticizers, hardeners, matting agents, thickening agents, surface active agents, polymers, antistatic agents, lubricants etc..
  • Antihalation dyes are chosen as a function of the applied red or infrared gas or semi-conductor laser source.
  • Preferred antihalation dyes applied in the hardcopy material used in the image-forming method according to the present invention are red light or infrared absorbing dyes.
  • At least one antihalation dye is preferably added to at least one emulsion layer in amounts necessary to reduce light scattering phenomena leading to a better sharpness.
  • Preferably antihalation dyes are added in variable amounts during coating in order to adjust the sensitivity of the hardcopy material. So it may be advantageous to introduce at least one antihalation dye by means of a dosing feeder just before coating to adjust the sensitivity of the photographic material as required by the product specifications.
  • the said antihalation dye or dyes may be present in the form of solutions thereof, in the form of a gelatinous dispersion or in a solid particle state.
  • the same or different or a mixture of different developing accelerators may be added to at least one of the hydrophilic layers at the emulsion side. More preferably at least one development accelerator is added to at least one of the protective layers, preferably to the topcoat layer.
  • Development acceleration may be accomplished with the aid of various compounds, preferably polyoxyalkylene derivatives having a molecular weight of at least 400 such as those described in e.g. US-A's 3,038,805; 4,038,075 and 4,292,400 and in EP-A 0 634 688.
  • Especially preferred developing accelerators are polyoxyethylenes containing (recurrent) thioether groups as disclosed e.g. in DE 1 522 396, in DE 2 360 878 and in EP-A 0 674 215, wherein the said applications were related with development acceleration of materials comprising AgBr and/or AgBr(I) emulsions.
  • the photographic hardcopy material used in the image-forming method according to the present invention may further comprise various other additives such as e.g. compounds improving the dimensional stability of the photographic element, UV-absorbers, spacing agents, hardeners, and plasticizers.
  • additives such as e.g. compounds improving the dimensional stability of the photographic element, UV-absorbers, spacing agents, hardeners, and plasticizers.
  • Plasticizers suitable for incorporation in the emulsions according to the present invention are e.g. glycol, glycerine, or the latexes of neutral film forming polymers including polyvinyl-acetate, acrylates and methacrylates of lower alkanols e.g. polyethylacrylate and polybutylmethacrylate.
  • Suitable additives for improving the dimensional stability of the photographic hardcopy film may be i.a. dispersions of a water-soluble or hardly soluble synthetic polymer e.g. polymers of alkyl(meth)acrylates, alkoxy(meth)acrylates, glycidyl (meth)acryla-tes, (meth)acrylamides, vinyl esters, acrylonitriles, olefins, and styrenes, or copolymers of the above with acrylic acids, methacrylic acids, ⁇ - ⁇ -unsaturated dicarboxylic acids, hydroxyalkyl (meth)acry-lates, sulphoalkyl (meth)acrylates and styrene sulphonic acids.
  • a water-soluble or soluble synthetic polymer e.g. polymers of alkyl(meth)acrylates, alkoxy(meth)acrylates, glycidyl (meth)acryla-tes, (meth)acryl
  • Suitable UV-absorbers may be i.a. aryl-substituted benzotriazole compounds as described in US-A 3,533,794, 4-thiazolidone compounds as described in US-A's 3,314,794 and 3,352,681, benzophenone compounds as described in JP-A 2784/71, cinnamic ester compounds as described in US-A's 3,705,805 and 3,707,375, butadiene compounds as described in US-A 4,045,229, and benzoxazole compounds as described in US-A 3,700,455.
  • the average particle size of spacing agents is comprised between 0.2 and 10 ⁇ m.
  • Spacing agents may be soluble or insoluble in alkali. Alkali-insoluble spacing agents usually remain permanently in the photographic element, whereas alkali-soluble spacing agents usually are removed therefrom in an alkaline processing bath.
  • Suitable spacing agents may be made i.a. of polymethyl methacrylate, of copolymers of acrylic acid and methyl methacrylate, and of hydroxypropylmethyl cellulose hexahydrophthalate. Other suitable spacing agents have been described in US-A 4,614,708.
  • Matting agents present in the material for use in the image-forming method according to the present invention are polymethylmethacrylate and/or silicium dioxide particles with a particle size diameter from 0.01 to 5 ⁇ m and more preferably from 0.025 to 2 ⁇ m that are added to protective topcoat layer.
  • any thickening agent Prior to coating any thickening agent may be used in order to regulate the viscosity of the coating solution, provided that they do not particularly affect the photographic characteristics of the silver halide light-sensitive photographic material.
  • Preferred thickening agents include aqueous polymers such as polystyrene sulphonic acid, dextran, sulphuric acid esters, polysaccharides, polymers having a sulphonic acid group, a carboxylic acid group or a phosphoric acid group as well as colloidal silica.
  • Polymeric thickeners well-known from the literature resulting in thickening of the coating solution may be used independently or in combination, even with colloidal silica.
  • Amounts may be suitably selected according to the kinds of silver halide (silver chloride, silver chloroiodide, silver chlorobromide or silver chlorobromoiodide in this case) and the kinds of layers or compounds to which these thickening agents are to be added.
  • Patents concerning thickening agents are US-A 3,167,410; Belgian Patent No. 558.143 and JP OPI Nos. 53-18687 and 58-36768. Negative effects on physical stability possibly resulting from the addition of polymeric compounds can be avoided by exclusion of those compounds and by restricting extra additions of colloidal silica.
  • the emulsions prepared and coated in the photographic hardcopy material used in the image-forming method according to the present invention are particularly advantageous for the formation of very thin emulsion layers e.g. layers with a layer thickness of less than 5 ⁇ m, containing less than 5 g of gelatin, preferably about 3 and more preferably about 2 g/m 2 .
  • Such thin coated layers offer the advantage that besides the rapid processing applicability and the rapid drying of the wet processed material an improvement in sharpness is observed.
  • the photographic elements used in the image-forming method of the present invention may further comprise various kinds of surface-active agents in the photographic emulsion layer or in at least one other hydrophilic colloid layer.
  • Suitable surface-active agents include non-ionic agents such as saponins, alkylene oxides as e.g.
  • polyethylene glycol polyethylene glycol/polypropylene glycol condensation products, polyethylene glycol alkyl ethers or polyethylene glycol alkylaryl ethers, polyethylene glycol esters, polyethylene glycol sorbitan esters, polyalkylene glycol alkylamines or alkylamides, silicone-polyethylene oxide adducts, glycidol derivatives, fatty acid esters of polyhydric alcohols and alkyl esters of saccharides; anionic agents comprising an acid group such as a carboxy, sulpho, phospho, sulphuric or phosphoric ester group; ampholytic agents such as aminoacids, aminoalkyl sulphonic acids, aminoalkyl sulphates or phosphates, alkyl betaines, and amine-N-oxides; and cationic agents such as alkylamine salts, aliphatic, aromatic or heterocyclic quaternary ammonium salts, aliphatic or heterocyclic ring-
  • drying characteristics in the processor are mainly determined by the water absorption of the hydrophilic layers of the photographic material, and since the water absorption is directly proportional to the gelatin content of the layers and inversely proportional to the amount of hardener, added to the layer, its composition is optimised with a low gelatin content and a high hardening degree in order to attain the object of this invention to allow hardener free processing within a from 30 to at most 50 seconds dry-to-dry cycle time.
  • a total amount of gelatin of less than 3 g/m 2 per side is present.
  • Hardeners may be added to the antistress layer before or during the coating procedure.
  • the binders of the photographic element especially when the binder used is gelatin, can be hardened with appropriate hardening agents such as those of the epoxide type, those of the ethylenimine type, those of the vinylsulfone type e.g. 1,3-vinylsulphonyl-2-propanol, chromium salts e.g. chromium acetate and chromium alum, aldehydes e.g. formaldehyde, glyoxal, and glutaraldehyde, N-methylol compounds e.g.
  • dimethylolurea and methyloldimethylhydantoin dioxan derivatives e.g. 2,3-dihydro-xy-dioxan, active vinyl compounds e.g. 1,3,5-triacryloyl-hexa-hydro-s-triazine, active halogen compounds e.g. 2,4-dichloro-6-hydroxy-s-triazine, and mucohalogenic acids e.g. mucochloric acid and mucophenoxychloric acid.
  • These hardeners can be used alone or in combination.
  • the binders can also be hardened with fast-reacting hardeners such as carbamoylpyridinium salts.
  • Preferred hardening agents used in the hardcopy material suitable for use in the image-forming method according to the present invention are formaldehyd and phloroglucinol, added respectively to the protective layer(s) and to the emulsion layer(s).
  • other preferred hardening agents are bis-vinyl-sulphonyl-methyl-ether (BVSME) or ethylene-bis-vinyl-sulphone.
  • the hardcopy material used in the image-forming method according to the present invention has a hardening degree corresponding with a water absorption of the unexposed material of less than 10 g/m 2 , and more preferably from 4 to 7 g/m 2 after immersion in demineralised water at 24°C during 10 minutes following the method described hereinbefore.
  • Backing layers applied to the material having at least one emulsion layer at one side of the hardcopy material used in the image-forming method according to the present invention essentially contain hydrophilic colloids, one or more antihalation dye(s), matting agent(s), surfactant(s), antistatic agent(s), lubricant(s) and hardening agent(s).
  • Amounts of hydrophilic colloids are chosen in order to prevent curl of the single side emulsion coated material, such as in US-A 5,155,013. Also non-swelling hydrophobic polymers can be used in the backing layer as has e.g. been described in US-A 5,326,686. Further measures to prevent curling have been disclosed e.g. in JP-A's 02024645; 02085847 and 02087138.
  • a common support of the photographic silver halide emulsion hardcopy material used in the image-forming method according to the present invention is a hydrophobic resin support.
  • Hydrophobic resin supports are well known to those skilled in the art and are made e.g. of polyester, polystyrene, polyvinyl chloride, polycarbonate, preference being given to polyethylene terephthalate and polyethylene naphthalate.
  • the hydrophobic resin support may be provided with one or more subbing layers known to those skilled in the art for adhering thereto a hydrophilic colloid layer.
  • subbing layers for polyethylene terephthalate supports are described e.g. in US-A's 3,397,988, 3,649,336, 4,123,278 and 4,478,907.
  • Coating of the different layers of the photographic hardcopy element used in the image forming method of the present invention may occur according to any of the known techniques for applying photographic coatings.
  • modern slide hopper and especially curtain coating techniques are applied.
  • polyacrylamides which are known to increase the shear viscosity can be added to the coating composition of the emulsion layer and/or protective antistress layer.
  • Suitable polyacrylamides are copoly(acrylamide-(meth)acrylic acid), e.g., COPOLY(acrylamide-acrylic acid-sodium acrylate) (87.5:4.1:8.4) in particular the commercial products ROHAFLOC SF710 and ROHAFLOC SF 580 from ROHM.
  • polyacrylamides are preferably used in amounts of 10 to 500 ppm in the coating composition of the antistress layer and coating occurs simultaneously with the emulsion layer by curtain coating. In this way the emulsion layer thickness can be reduced and coating can proceed at increased speed.
  • the said convenient imaging system in accordance with this invention is characterised by the following consecutive handling steps of the hardcopy material described hereinbefore:
  • the imaging system provides at least 4 consecutive sheets having a size format of 35.56 cm x 43.18 cm (17"x14") per minute of a light-sensitive hardcopy material of medical, electronically stored images.
  • Suitable lasers may be gas lasers or solid state lasers.
  • a suitable gas laser a helium/neon gas laser is preferred (absorption maximum 633 nm).
  • a preferred solid state laser an infrared laser diode having a more bathochrome absorption maximum at 820 nm is used.
  • a preferred laser imager fulfilling the mentioned advantages we refer to the laser imager MATRIX LR 3300, trade name product marketed by Agfa-Gevaert.
  • the compound according to formula (I) mentioned hereinbefore corresponds to (iso)ascorbic acid, l-ascorbic acid and tetramethyl reductic acid.
  • developing proceeds with a solution comprising a hydroquinone and a compound corresponding to formula (I) in a ratio by weight of up to 9:1 and more preferably of up to 1:1.
  • said development processing proceeds with a solution comprising thiocyanate ions in amounts between 10 -3 and 10 -1 molar and/or in amounts of from 0.1 to 5 g per litre a compound corresponding to the formula (II), accompanied by charge compensating anions, wherein at least divalent group R contains at least one oxyethylene group and wherein Z' and Z", being the same or different, are composed of enough atoms to form a heterocyclic aromatic 5- or 6-ring.
  • the said heterocyclic aromatic rings are the same or different and represent a pyridine, a pyrimidine, an imidazol, a benzimidazol, a thiazol, a benzothiazol or a derivative thereof. Especially use of pyridinium salts is preferred. In a further embodiment at least one divalent group R represents at least 3 oxyethylene-units.
  • a particularly suitable developer solution for use in developing the hardcopy material within the scope of this invention is a so-called one-part "low-sludge" developer which comprises a reduced amount of sulphite and ascorbic acid, acting as a main developer and anti-oxidant (see Examples).
  • a suitable fixer solution for use in fixing the hardcopy material within the scope of the image-forming method according to the present invention is a fixer which comprises an amount of less than 25 g of potassium sulphite per liter without the presence of acetic acid and wherein said fixer has a pH value of at least 4.5, in order to make the fixer solution quasi odourless.
  • the fixation time is reduced to about 2 to 10 seconds.
  • regenerate the developer solution and the fixer solution for use in the processing of the hardcopy material in the method according to the present invention should be recommended to regenerate the developer solution and the fixer solution for use in the processing of the hardcopy material in the method according to the present invention with concentrates of developer solutions and fixer solutions. In these circumstances, no dilution and mixing procedures are required before the regeneration bottles are adjusted to the processing unit. Moreover regeneration is kept to a minimum as the processing of materials according to the present invention are coated from very low amounts of emulsion crystals rich in silver chloride. Preferred minimum regeneration or replenishment amounts are from 20 to 100 ml/m 2 , more preferred from 25 to 75 ml/m 2 and still more preferred from 25 to 50 ml/m 2 of developed material.
  • silver halide materials comprising such fine cubic crystals rich in silver chloride are much more sensitive to the formation of sludge in a developer and/or fixer, it has been established that in the preferred developer used in the method of image-forming according to the present invention having a composition as described hereinbefore, a very low sludge level is attained.
  • the said laser imager MATRIX LR 3300 is linked with the CURIX HT 330 processing unit on top of it, as has e.g. been realised in the laser imager processor MATRIX LR 3300P Laser Imager Processor, trade name product marketed by Agfa-Gevaert, the objectives of this invention can be fully realized.
  • CURIX 330 again is a trade name product marketed by Agfa-Gevaert.
  • any combination of a laser imager and a processing unit may be used and is not limited to the laser imagers and processors described hereinbefore, the proviso that the respective requirements for both of them are fulfilled, in accordance with the objects of the present invention.
  • This example demonstrates the advantages of emulsions comprising AgCl(Br) crystals over emulsions comprising AgBr(I) crystals, both having a small average grain size between 0.2 and 0.3 ⁇ m.
  • the emulsion was washed with a solution of demineralised water containing 0.46 g of sodium chloride per litre after flocculation by addition of polystyrene sulphonic acid to the acidified emulsion.
  • a solution of demineralised water containing 0.46 g of sodium chloride per litre after flocculation by addition of polystyrene sulphonic acid to the acidified emulsion.
  • the pH of the said emulsion was adjusted at 5.15; the pAg at 7.00.
  • a cubic silver chlorobromide emulsion having a mean grain size of 0.26 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as described hereinbefore for the preparation of the Emulsion A except for:
  • a cubic silver chlorobromide emulsion having a mean grain size of 0.28 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as described hereinbefore for the preparation of the Emulsion A except for:
  • a cubic silver chlorobromide emulsion having a mean grain size of 0.32 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as described hereinbefore for the preparation of the Emulsion A except for:
  • a cubic silver chlorobromide emulsion having a mean grain size of 0.39 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as in the preparation of the Emulsion A except for:
  • the emulsion was washed with a solution of demineralised water containing 0.46 g of sodium chloride per liter after flocculation by addition of polystyrene sulphonic acid to the acidified emulsion.
  • a solution of demineralised water containing 0.46 g of sodium chloride per liter After flocculation by addition of polystyrene sulphonic acid to the acidified emulsion.
  • the emulsion was washed with water after application of a conventional flocculation method as described for emulsion A. An amount of 126 g of gelatin was added thereto.
  • a cubic silver bromoiodide emulsion having a mean grain size of 0.23 ⁇ m was obtained having a bromide content of 98 mole %.
  • the pH of the emulsion was adjusted to 6.5, the pAg thereof was adjusted to 7.00 and the temperature was raised to 50°C.
  • Added amounts of ripening agents were: 8 mg of sodium thiosulphate, 21 mg of chloro auric acid, 42 mg of ammonium thiocyanate and 8 mg of para-toluene thiosulphonate. Chemical sensitisation was carried out at 50°C to give an optimum fog-sensitivity relationship.
  • a cubic silver bromoiodide emulsion having a mean grain size of 0.25 ⁇ m and a silver bromide content of 98 mole % was prepared in the same way as described hereinbefore for the preparation of the Emulsion F except for:
  • a cubic silver bromoiodide emulsion having a mean grain size of 0.27 ⁇ m and a silver bromide content of 98 mole % was prepared in the same way as described hereinbefore for the preparation of the Emulsion F except for:
  • a cubic silver bromoiodide emulsion having a mean grain size of 0.33 ⁇ m and a silver bromide content of 98 mole % was prepared in the same way as described in the preparation method of Emulsion F except for:
  • a sensitising dye (Sensitizing Dye (1)) was added in a amount of 0.16 mmole per mole of silver to each of the Emulsions A to E. In this way the emulsions were sensitised in order to become sensitive to red light.
  • an antifading agent (Compound (1)) was added, 65 mg (per mole of Ag) of 1-phenyl-5-mercaptotetrazole and 260 mg (per mole of Ag) of 1-p-carboxy-phenyl-5-mercaptotetrazole were added as stabilisers and 106 mg (per mole of Ag) fluoroglucinol as a surfactant were added together with polymethyl acrylate latex (in an amount of 140 % based on the weight amount of gelatin binder) used as a plasticizer.
  • the developed samples were fixed in G334, tradename of the corresponding fixer, marketed by Agfa-Gevaert N.V., followed by rinsing with water.
  • the colour “hue” of the developed silver was evaluated qualitatively and quantitatively: the ratio was calculated from the densities obtained by measurement of the said densities at total density of 2.5 through a filter transparent for blue and red light respectively.
  • Application of this method evaluates the transmission characteristics of the hue of the developed material in a quantitative manner.
  • the “covering power” is the ratio of the maximum density and the amount of developed silver measured in the same density region. The higher the covering power, the less silver is required in order to provide a good maximum density. As a consequence thereof the developability will be better and regeneration amounts of the developer and fixer per square meter will be smaller.
  • Emulsion A in combination of DEV1 may further cause a decrease in the amount of coated silver of 35% if compared with the reference Emulsion I, developed in the reference developer G138.
  • This example demonstrates the positive influence of an iridium dopant incorporated into the crystal lattice of silver chloride or chlorobromide emulsions on the development latitude.
  • a cubic silver chlorobromide emulsion having an average grain size of 0.23 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as described for the preparation of the Emulsion A except for the addition of 4.7 x 10 -6 mole of potassium hexachloroiridate(III) to solution 3.
  • a cubic silver chlorobromide emulsion having an average grain size of 0.23 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as described for the preparation of the Emulsion A except for the addition of 9.4 x 10 -6 mole of potassium hexachloroiridate(III) to solution 3.
  • a cubic silver chlorobromide emulsion having an average grain size of 0.23 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as described for the preparation of the Emulsion A except for the addition of 1.6 x 10 -5 mole potassium hexachloroiridate(III) to solution 3.
  • S1 and S3 are the sensitivities measured at density 1.00, respectively 3.00, above fog level.
  • G1 and G2 are the average gradients between densities of 0.40 and 1.00 above fog, and between densities 1.80 and 2.40 above fog, respectively.
  • Table II Em. Ir-comp. ( ⁇ mole/mole of Ag) Devel. time Devel. temp.
  • a cubic silver bromoiodide emulsion having an average grain size of 0.23 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as described in the preparation method of the Emulsion F except for the addition of 7.8 x 10 -6 mole of potassium hexachloroiridate(III) to solution 6 and 8.2 x 10 -6 mole of potassium hexachloroiridate(III) to solution 8.
  • the emulsion M was coated and exposed as has been described for the AgBr(I) emulsions in Example 1.
  • Table III lists the sensitometric differences obtained after development at a temperature of 30°C and 36°C respectively during 11 seconds in DEV1.
  • Table III Emulsion Composition Ir-compound ( ⁇ mole per mole of Ag) ⁇ Fog x 1000 ⁇ S1 ⁇ S3 ⁇ %G1 ⁇ %G2 A AgCl (Br) 0 23 24 33 112 123 L AgCl (Br) 5.3 5 9 7 93 103 F AgBr (I) 0 6 14 20 108 125 M AgBr (I) 5.3 7 11 13 99 96
  • Emulsion A was chemically sensitised with Se as follows:
  • a cubic silver chlorobromide emulsion having an average grain size of 0.23 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as in the preparation of Emulsion A except for the addition of 1 mg of compound (6) and the performance of the chemical sensitisation at 50°C.
  • a cubic silver chlorobromide emulsion having an average grain size of 0.23 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as in the preparation of the Emulsion A except for the addition of 2.5 mg of compound (7) and the temperature of the chemical sensitisation being 50°C.
  • a cubic silver chlorobromide emulsion having an average grain size of 0.23 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as in the preparation of the Emulsion A except for the absence of ammonium thiocyanate in this preparation method. 1 mg of compound (6) was further added and the chemical sensitisation was carried out at 50°C.
  • a cubic silver chlorobromide emulsion having an average grain size of 0.23 ⁇ m and a silver chloride content of 98 mole % was prepared in the same way as in the preparation of the Emulsion A except for the absence of ammonium thiocyanate. 2.5 mg of compound (7) was added and the chemical sensitisation was carried out at 50°C.
  • Table IV shows the results obtained after development for 11 seconds in DEV1 at 35°C for the coatings of the emulsions A and A2-A5 differing in chemical sensitisation: Table IV Emulsion Fog x 1000 S1 S3 G1 G2 A 0 135 168 355 585 A2 18 109 146 294 584 A3 19 110 147 294 589 A4 6 120 156 314 597 A5 0 123 159 327 602
  • An infrared sensitising dye (Sensitising Dye (2)) was added in a amount of 0.08 mmole/mole of Ag to the Emulsion A after addition of compound (8), which was added in a amount of 2.2 mmole/mole of Ag.
  • Example V shows the sensitometric data of the red sensitised (HeNe) and infrared sensitised Emulsion A.
  • Table V Spectral sensitisation and exposure source Fog x 1000 S1 S3 G1 G2 HeNe (633 nm) 0 135 168 355 585 IR (820 nm) 0 160 209 334 437
  • Table V demonstrates that the AgCl(Br) emulsions are also suitable for infrared applications.
  • This example makes a comparison between development in a developer comprising hydroquinone and a developer comprising ascorbic acid as main developing agents.
  • This example demonstrates that superior sensitometric results can be obtained for silver halide photographic materials coated from a AgCl(Br) emulsion and developed in a suitable developer designed therefor in comparison with a silver halide photographic material coated from a AgBr(I) emulsion, developed in the standard developer G138.
  • Table VII shows the results after development for 11 seconds at 36°C for materials coated from Emulsions A, F, J and M.
  • This Example demonstrates that the regeneration of the developer for a material comprising silver chlorobromide emulsions can be decreased in comparison with a material comprising silver bromoiodide emulsions.
  • the sensitivity S1 remained constant with an accuracy of ca. 2 sensitivity points during exhaustion of 500 m 2 of a material containing Emulsion A.

Claims (14)

  1. Procédé de reproduction pour une image médicale mémorisée par voie électronique sur un matériau de tirage, comprenant un support et sur une seule face de celui-ci une couche d'émulsion aux halogénures d'argent et une couche colloïdale hydrophile, ladite couche d'émulsion comprenant des cristaux cubiques homogènes de chlorure d'argent, de chloro-iodure d'argent, de chlorobromure d'argent et/ou de chlorobromo-iodure d'argent sensibilisés au rouge ou à l'infrarouge avec une quantité d'ions de chlorure d'au moins 70% de moles et avec une quantité d'iodure ne dépassant pas 1% de mole et dont la taille moyenne des cristaux est comprise entre 0,12 et 0,30 µm; lesdits cristaux étant couchées à raison d'une quantité, exprimée comme la quantité équivalente de nitrate d'argent, comprise entre 2 et 6 g par mètre carré, et ledit matériau présentant un degré de durcissement correspondant à une absorption d'eau d'au plus 3 g par gramme de gélatine sur la face émulsionnée, ladite absorption d'eau étant mesurée comme suit:
    - le film sec est maintenu pendant 15 minutes dans une chambre de conditionnement à 20°C et à 30% d'humidité relative,
    - la couche dorsale de finition du film sec est recouverte d'un ruban imperméable à l'eau,
    - pesée du film sec,
    - le matériau non exposé est immergé dans de l'eau déminéralisée à 24°C, pendant 10 minutes,
    - l'excédent d'eau présent sur les couches les plus externes est éliminé par aspiration et
    - le poids du film mouillé est immédiatement déterminé et
    - les différences entre les poids mesurés du film mouillé et du film sec sont calculées et puis calculées par mètre carré de film et le résultat est divisé par le grammage de l'enduit de gélatine par mètre carré;
    ledit procédé étant caractérisé par les étapes consistant à
    - exposer ledit matériau suivant une image au laser rouge ou infrarouge adressé par voie électronique et consécutivement
    - traiter pour développer dans un révélateur exempt de durcisseurs dans un laps de temps inférieur à 20 s pendant une durée de traitement total sec à sec entre 30 et 50 s, ledit révélateur renfermant un composé correspondant à la formule (I), un précurseur de celui-ci, un dérivé de celui-ci et/ou un sel métallique de celui-ci dans laquelle
    A, B et D, indépendamment l'un de l'autre, représentent chacun un atome d'oxygène ou NR1;
    X représente un atome d'oxygène, un atome de soufre, NR2, CR3R4, C=O, C=NR5 ou C=S;
    Y représente un atome d'oxygène, un atome de soufre, NR'2, CR'3R'4, C=O, C=NR'5 or C=S;
    Z représente un atome d'oxygène, un atome de soufre, NR"2, CR"3R"4, C=O, C=NR"5 ou C=S;
    n est égal à 0, 1 ou 2;
    R1 à R5, R'2 à R'5, R"2 à R"5, indépendamment l'un de l'autre, représentent chacun un atome d'hydrogène, un groupe alkyle, un groupe aralkyle, un groupe hydroxyalkyle, un groupe carboxyalkyle, un groupe alcényle, un groupe alkynyle, un groupe cycloalkyle, un groupe cycloalcényle, un groupe aryle ou un groupe hérérocyclyle, substitués ou non substitués;
    et dans laquelle
    R3 et R4, R'3 et R'4, et R"3 et R"4 peuvent en plus se combiner pour former un noyau; et dans laquelle
    au cas où X=CR3R4 et Y=CR'3R'4, R3 et R'3 et/ou R4 et R'4 peuvent former un noyau et dans laquelle au cas où Y=CR'3R'4 et Z=CR"3R"4
    avec n = 1 ou 2, R'3 et R"3 et/ou R'4 et R"4 peuvent former un noyau;
    - régénérer ledit révélateur avec un taux ne dépassant pas 100 ml par mètre carré de matériau développé;
    - fixer ledit matériau de tirage dans un laps de temps entre 2 et 10 s;
    - rincer et sécher.
  2. Procédé selon la revendication 1, caractérisé en ce que lesdits cristaux dans ledit matériau de tirage possèdent au moins 90% de moles d'ions de chlorure.
  3. Procédé selon la revendication 1 ou 2, caractérisé en ce que lesdits cristaux dans ledit matériau de tirage possèdent une taille moyenne des cristaux entre 0,15 et 0,25 µm.
  4. Procédé selon l'une quelconque des revendications 1 à 3, caractérisé en ce que lesdits cristaux dans ledit matériau de tirage contiennent de l'iridium(III) en tant que dopant dans une quantité comprise entre 0,5 et 20 µmole par mole d'argent.
  5. Procédé selon l'une quelconque des revendications 1 à 4, caractérisé en ce que lesdits cristaux sont sensibilisés chimiquement en présence d'au moins un composé au sélénium.
  6. Procédé selon l'une quelconque des revendications 1 à 5, caractérisé en ce que lesdits cristaux sont sensibilisés spectralement à la région rouge ou infrarouge des longueurs d'ondes du spectre à l'aide d'un sensibilisateur spectral choisi parmi les cyanines et mérocyanines di-, tri-, tétra-, penta- et heptaméthiniques, les rhodacyanines, et les mérocyanines polynucléaires.
  7. Procédé selon l'une quelconque des revendications 1 à 6, caractérisé en ce que la teneur totale en gélatine sur la face émulsionnée est comprise entre 1 et 3 g/m2.
  8. Procédé selon l'une quelconque des revendications 1 à 7, caractérisé en ce que a la teneur en argent sur la face émulsionnée, exprimée comme la quantité équivalente de nitrate d'argent, est comprise entre 3 et 5 g/m2.
  9. Procédé selon l'une quelconque des revendications 1 à 8, caractérisé en ce que ledit matériau de tirage est durci à l'aide de di(vinylsulfonyl)méthane ou d'éthylène de di(vinylsulfone).
  10. Procédé selon l'une quelconque des revendications 1 à 9, caractérisé en ce que le développement lors dudit traitement de développement est effectué à l'aide d'une solution comprenant des ions de thiocyanate dans une quantité molaire allant de 10-3 à 10-1 et/ou dans une quantité de 0,1 à 5 g par litre ainsi qu'un composé répondant à la formule (II) ci-après, accompagnée d'anions compensateurs de charge, dans laquelle au moins le groupe divalent R contient au moins un groupe d'oxyéthylène et dans laquelle Z' et Z", identiques ou différents, sont constitués d'une quantité suffisante d'atomes pour former un noyau aromatique hétérocyclique penta- ou hexagonal.
  11. Procédé selon l'une quelconque des revendications 1 à 10, caractérisé en ce le développement pendant ledit traitement de développement est effectué à l'aide d'une solution comprenant de l'hydroquinone et un composé répondant à la formule (I) dans un rapport pondéral maximal de 9:1.
  12. Procédé selon l'une quelconque des revendications 1 à 10, caractérisé en ce que le développement pendant ledit traitement de développement est effectué à l'aide d'une solution comprenant de l'hydroquinone et un composé répondant à la formule (I) dans un rapport pondéral maximal de 1:1.
  13. Procédé selon l'une quelconque des revendications 1 à 12, caractérisé en ce que les taux de régénération pendant ledit traitement de développement varient entre 25 et 75 ml/m2 de matériau développé.
  14. Procédé selon l'une quelconque des revendications 1 à 13, comprenant les étapes consistant à
    - exposer ledit matériau de tirage à l'aide d'une source laser rouge ou infrarouge dans un laps de temps inférieur ou égal à 10 s pour des formats de découpage de 35,56 cm x 43,18 cm (14"x17");
    - transporter ledit matériau de tirage vers une développeuse automatique dans un temps maximal de 5 s;
    - traiter ledit matériau de tirage sec à sec dans ladite développeuse automatique dans un laps de temps allant de 30 à 50 s à l'aide de bains révélateur et fixateur exempts de durcisseurs;
    - procurer au moins 4 feuilles consécutives par minute dans un format de découpage de 35,56 cm x 43,18 cm (17"x14").
EP97200589A 1996-03-07 1997-03-01 Procédé de reproduction d'une image médicale mémorisée électroniquement sur matériau photographique sensible à la lumière Expired - Lifetime EP0794456B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP97200589A EP0794456B1 (fr) 1996-03-07 1997-03-01 Procédé de reproduction d'une image médicale mémorisée électroniquement sur matériau photographique sensible à la lumière

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP96200622 1996-03-07
EP96200622 1996-03-07
EP97200589A EP0794456B1 (fr) 1996-03-07 1997-03-01 Procédé de reproduction d'une image médicale mémorisée électroniquement sur matériau photographique sensible à la lumière

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EP0794456B1 true EP0794456B1 (fr) 2003-01-29

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