US3721823A - Color radiography - Google Patents

Color radiography Download PDF

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US3721823A
US3721823A US00852236A US3721823DA US3721823A US 3721823 A US3721823 A US 3721823A US 00852236 A US00852236 A US 00852236A US 3721823D A US3721823D A US 3721823DA US 3721823 A US3721823 A US 3721823A
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image
color
silver
silver halide
coupler
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Lishout J Van
J Jaeken
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Agfa Gevaert NV
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    • 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
    • G03C8/00—Diffusion transfer processes or agents therefor; Photosensitive materials for such processes
    • G03C8/02—Photosensitive materials characterised by the image-forming section
    • G03C8/04—Photosensitive materials characterised by the image-forming section the substances transferred by diffusion consisting of inorganic or organo-metallic compounds derived from photosensitive noble metals
    • G03C8/045—Photosensitive materials characterised by the image-forming section the substances transferred by diffusion consisting of inorganic or organo-metallic compounds derived from photosensitive noble metals with the formation of a subtractive dye image
    • 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
    • G03C1/46—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein having more than one photosensitive layer
    • 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
    • G03C1/485—Direct positive emulsions
    • G03C1/48538—Direct positive emulsions non-prefogged, i.e. fogged after imagewise 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
    • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
    • G03C5/16—X-ray, infrared, or ultraviolet ray processes
    • 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
    • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
    • G03C7/18—Processes for the correction of the colour image in subtractive colour photography
    • 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
    • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
    • G03C7/28—Silver dye bleach processes; Materials therefor; Preparing or processing such materials
    • 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
    • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
    • G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials
    • G03C7/32—Colour coupling substances
    • G03C7/333—Coloured coupling substances, e.g. for the correction of the coloured image
    • G03C7/3335—Coloured coupling substances, e.g. for the correction of the coloured image containing an azo chromophore
    • 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
    • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
    • G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials
    • G03C7/32—Colour coupling substances
    • G03C7/34—Couplers containing phenols
    • G03C7/346—Phenolic couplers
    • 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
    • G03C8/00—Diffusion transfer processes or agents therefor; Photosensitive materials for such processes
    • G03C8/02—Photosensitive materials characterised by the image-forming section
    • G03C8/08—Photosensitive materials characterised by the image-forming section the substances transferred by diffusion consisting of organic compounds
    • G03C8/10—Photosensitive materials characterised by the image-forming section the substances transferred by diffusion consisting of organic compounds of dyes or their precursors
    • G03C8/12—Photosensitive materials characterised by the image-forming section the substances transferred by diffusion consisting of organic compounds of dyes or their precursors characterised by the releasing mechanism
    • G03C8/14—Oxidation of the chromogenic substances
    • G03C8/16—Oxidation of the chromogenic substances initially diffusible in alkaline environment

Definitions

  • R is an alkyl radical or an aryl radical
  • R is a hydrogen atom, an amino radical, an alkyl radical, an alkylene radical, an aryl radical or a heterocyclic radical, I
  • X is a hydroxyl radical, an amino radical, analkyl radical, an aryl radical, and a heterocyclic radical
  • Y represents the non-metallic atoms necessary to complete a nitrogen-containing heterocyclic nucleus
  • i Z represents the non-metallic atoms necessary to complete a heterocyclic nucleus containing five to six members, at least one of which is a nitrogen atom
  • the present invention relates to a method for producing color radiographs having an improved information content in comparison with black-and-white radiographs.
  • radiographs i.e., photographic images produced directly or indirectly by means of penetrating rays, e.g., 'y-rays, X-rays'and other highly energetic radiation, by adding to differences in brightness, differences in color saturation and hue.
  • a developable latent silver image is formed by means of directly or indirectly recorded penetrating radiation and is processed in such a way that at least two images of contrasting color and of opposite gradation are obtained.
  • the recording by means of penetrating radiation includes a direct as well as an indirect exposure.
  • the indirect exposure is an exposure to visible and/or U.V. light produced by converting penetrating radiation, i.e., high energetic radiation such as X-rays,'alpha, beta or gamma rays and neutrons suited for makingradiographs, into visible and/or U.V. light and/or electrons obtained as a secondary emission" from e.g., lead screens.
  • the indirect exposure can be a screen-exposure" wherein penetrating radiation is used, which is projected and converted into visible light and/or U.V. light on a fluorescing screen.
  • the recording includes all types of exposure with radiation that produces a latent silver image, e.g., simultaneous exposure to a pattern of such radiation, and also scanning-wise exposure e.g., by means of a light spot that is modulated according to the radiographic information to be recorded.
  • contrasting colors used in the present invention points to colors that visually markedly differ from each other, e.g., blue and red, red and yellow, red and green, black and yellow, black and green, black also being considered as a color in the present invention, so that the combination of (a) silver image(s) with (a) color image(s) of opposite gradation is not excluded.
  • Good detail reproduction can be obtained by producing color images in different complementary color pairs e.g., blue and yellow, green and magenta.
  • Mixtures of colors are included, e.g., yellowish green color tones and color tones which lay between yellow and red, to which the human eye is particularly sensitive, can be used too.
  • the legibility of lettering color of lettering on colored background has been described by Boris Townsend in The British Journal of Photography, Jan. 1969 p. 106 and gives preferred combinations of contrasting colors e.g., black image parts on a yellow background.
  • the photographic image is constituted of two color images these need not necessarily be formed in the same layer of a same silver halide photographic material, but may be formed in different layers thereof.
  • positive and negative color image in the method according to the present invention may be formed at either side of the support of the radiographic film.
  • the invention also includes the production of a color radiograph wherein two color images are obtained in one or more layers at one side of a support, and one or two of the color images are also obtained at the other side of the support.
  • the color images of contrasting colors need not be formed in one emulsion layer but may be formed by the superposition of two or more color images, wherein all of them may be either positive or negative, and may be obtained in several layers.
  • a red positive image may be constituted of a yellow positive image produced in one layer and of a magenta positive image produced in an other layer either adjacent to the first layer or remote therefrom, e.g., at the other side of the support.
  • two color images of opposite gradation are produced in the same recording material and more preferably in the same silver halide emulsion layer.
  • one color of the radiographic image obtained may mainly stress variations in the higher densities.
  • the sensitometric characteristics of the positive image may differ from those of the negative image.
  • the contrast of the positive image may be softer or harder than that of the negative image, or the sensitivity of the silver halide emulsion layer(s) wherein one image is produced may differ from that of the layer(s) wherein the other image is formed.
  • the mentioned differences in the sensitometric properties may be obtained by a particular processing of a standard type silver halide emulsion layer or layer system or by a common processing of a film with (a) particularly composed silver halide emulsion layer(s).
  • the recognition of density differences in the lower and the higher densities may be improved by viewing or projecting the radiographic image by means of colored light (e.g. using a color filter set in combination with white light) to obtain a hue, the contrast of which is low in respect of one color image and high in respect of the other.
  • colored light e.g. using a color filter set in combination with white light
  • Photographic masking may be described as a modification of the density distribution of a negative by the combination in register with a positive image having a gradation opposite to that of the negative image.
  • said integral masking process can be modified in such a way that negative and positive color images are obtained wherein the positive color image has a density substantially higher than is necessary for compensating the side absorptions of the negative color image.
  • the maximum density of the image of opposite gradation is as high as or amounts to at least 50 percent of the maximum density of the main color of the primary color image.
  • This can be realized with either of the existing integral masking systems by adapting the concentration of the proper compounds and the processing for producing the color image of opposite gradation.
  • said silver halide emulsion preferably contains the colored color couplers in such a concentration that in the areas, wherein by color development after direct or indirect" exposure to said penetrating radiation no primary image has been formed, sufficiently colored color coupler is left to obtain a secondary image the maximum density of which is higher than that normally obtained in masking procedures for compensating the influence of the densities of the side absorption(s) of the primary color image.
  • the primary image it is not necessary for the primary image to be a negative image in respect of the original since for the purpose of the present invention a silver halide emulsion of the direct-positive type can be used just as well.
  • Such silver halide emulsions can produce a direct-positive silver image e.g., according to the Herschel or solarization effect.
  • a negative image is formed by means of a color coupler suited for forming a quinonimine or azomethine dye on color development of the exposed silver halide with an aromatic primary amino developing agent and a positive image (secondary image) is obtained by oxidation of a compound or oxidative copulation of a compound with color coupler being residual after color development.
  • oxidatively coupling compounds are 4-amino-pyrazolones described in the UK. Pat. specifications Nos. 880,862 filed Dec. 31, 1956 and 975,930 filed June 27, 1961 both by Gevaert Photo- Producten N.V. and in the U.S. Pat. specs. Nos. 3,012,884 and 3,013,879 both of Maurice Antoine de Ramaix and Jan Jaeken issued Dec. 12, 1961 and issued Dec. 19,1961.
  • 4-aminopyrazolones are corresponding to the following general formula:
  • R represents an alkyl group of at most five carbon atoms
  • R represents an alkyl group of at most five carbon atoms, a phenyl group or a substituted phenyl group
  • R represents an alkyl group of more than five carbon atoms which inhibits migration in colloid layers of the compound involved.
  • Suitable oxidatively coupling compounds are p-phenylene-diamines with sterically hindered amino group as described e.g., in the published U.K. Pat. specification No. 1,153,561 filed Jan. 18, 1966 by Gevaert-Agfa N.V.
  • R represents a hydrogen atom, a monovalent organic group, or an organic bivalent group linked to an ortho-atom of the aromatic group represented by A,
  • R represents a monovalent organic group, or a bivalent organic group linked to an ortho-atom of the aromatic group represented by A, or
  • R together with R forms a nitrogen-containing nucleus including a substituted nucleus
  • A represents an aromatic group, which in the p-position to the is substituted by the -NHR group, and in the 0- positions in respect of the Nl-l-R group is substituted with a halogen atom, an alkyl group, an alkoxy group, a cyano group, an acyl group, an acyl-substituted amino group, a sulphamyl group, an alkylsulphonyl group, an arylsulphonyl group, a sulpho group or a carboxylic group in acid or salt form, A including such an aromatic group which is further substituted.
  • suitably oxidatively coupling compounds are sterically hindered phenols described in the French wherein each of R, and R represents a sterically hindering group selected from the group consisting of ten.- butyl, cyclohexyl and phenyl, and
  • R represents a member selected from the group consisting of a hydrogen atom, a halogen atom and a radical which is sufficiently unstable for being split off on treatment with an oxidizing photographic bleaching bath.
  • Particularly useful oxidatively coupling compounds are further hydrazones capable of producing azine compounds by oxidative copulation with aromatic hydroxy compounds, e.g., phenols and naphthols and 2-pyrazoline-5-one compounds.
  • aromatic hydroxy compounds e.g., phenols and naphthols and 2-pyrazoline-5-one compounds.
  • Compounds having such copulation ability contain theamidrazone system or a vinylog thereof represented by Particularly suited compounds for application in such a process are described e.g., in the UK. Pat. specification Nos. 975,932 filed Nov, I3, 1959, 993,749 filed June 30, 1962 and 995,798 filed May 4, 1962 all by Gevaert Photo-Producten N.V., in the U.S. Pat. spec. No.
  • Preferably used hydrazone compounds contain a grouping of the following structure wherein R represents a group of the formula CONl-l or SO X wherein X represents a hydroxyl, an amino or a substituted amino group, a heterocyclic group, an alkyl or a substituted alkyl group, an aryl or a substituted aryl group,
  • R represents a hydrogen atom, an alkyl group, an
  • L represents a methine group or a nitrogen atom
  • n is a positive integer from 1 to 2.
  • Preferred hydrazone compounds correspond to the following general formulas wherein R, is a member of the group consisting of a hydrogen atom and an acetyl group,
  • R is a member of the group consisting of an alkyl radical and an aryl radical
  • Z represents the non-metallic atoms necessary to complete a heterocyclic nucleus containing 5-6 members, at least one of which is a nitrogen atom,
  • X is a member of the group consisting of an hydroxyl radical, an amino radical, an alkyl radical, an aryl radical, and a heterocyclic radical;
  • R is a member of the group consisting of a hydrogen atom and an acyl radical
  • Y represents the non-metallic atoms necessary to complete a nitrogen-containing heterocyclic nucleus
  • R is a member of the group consisting of a hydrogen atom, an amino radical, an alkyl radical, an alkylene radical, an aryl radical, and a heterocyclic radical, and
  • X is a member of the group consisting of an hydroxyl radical, an amino radical, an aliphatic hydrocarbon radical, an aryl radical, and a heterocyclic radical.
  • the masking compounds are preferably used in an amount substantially higher than is necessary'for producing a masking group wherein R represents a sulphonic acid group, an acyl group or an amide group, e.g., a sulphonylalkyl group, a sulphonylaryl group, a CON1-l group or a SO NH group including these groups in substituted form.
  • R represents a sulphonic acid group, an acyl group or an amide group, e.g., a sulphonylalkyl group, a sulphonylaryl group, a CON1-l group or a SO NH group including these groups in substituted form.
  • the masking compound and color coupler need not to be incorporated in diffusionresistant form into the silver halide emulsion but may be introduced therein during the processing from a developing bath.
  • the oxidative copulation of the masking compound with the color coupler proceeds very well in a conventional alkaline photographic bleaching bath.
  • the secondary image is produced independently from the color couplers used for the formation of the primary color image.
  • Said masking technique and suitable compounds therefor are described in the German Pat. specification No. 1,083,125 filed Dec. 11, 1958 by Agfa A.G., the U.K. Pat. specification No. 916,657 filed Dec. 11, 1959 by Agfa A.G. and the U.S. Pat. spec. No. 3,186,840 of Walter Puschel, Ottmar Wahl, Willibald Pelz, Hans Schellenberger and Karl Loffler issued June 1, 1965 and U.S. Pat. No. 3,378,554 of Walter Puschel, Hans Schellenberger, Karl Loffler, Ottmar Wahl and Willibald Pelz issued Apr. 16, 1968.
  • the said colorless dihydrazone coupler stands in competition with the color coupler in the reaction with the oxidized developing agent.
  • the non-reacted dihydrazone is oxidized in the photographic bleaching bath and forms a product having the required color for compensating the side absorption(s) of the primary color image.
  • the system as described e.g., in the said U.K.
  • Pat. specification No. 916,657 and U.S. Pat. spec. Nos. 3,186,840 and 3,378,554 is particularly useful for producing a yellow secondary image.
  • the system may be modified for the purpose of the present invention, e.g., by producing as primary image a blue image and as secondary image a yellow image.
  • the color coupler and the colorless dihydrazone are incorporated into separate silver halide emulsion layers so that difficulties arising from differences in velocity of copulation of the oxidized developing agent with said dihydrazone and said color coupler respectively can be kept under control more easily.
  • a preferred photographic material suited for use according to the present invention contains a color coupler or mixture of color couplers by means of which on color development with an aromatic primary amino developing agent a primary dye image is formed, which absorbs in the red region (700-600 nm) of the visible spectrum and also in the green region (600-500 nm) for at least 30 percent in respect of the red region.
  • a material also contains another compound e.g., a said hydrazone compound by means of which in the photographic bleaching bath a secondary dye image contrasting in color to the primary dye image and having a gradation opposite to that of the primary dye image is formed.
  • the absorption in the blue region (400-500 nm) of the primary dye image at 450 nm is not higher than the maximum absorption in the green region of the spectrum.
  • the primary dye image having the above described absorption characteristics can be formed by means of a mixture of cyanand magenta-forming couplers or a single coupler producing on copulation with the oxidation product of an aromatic primary amino developing agent e.g., a p-phenylenediamine derivative a dye absorbing in the red and green regions as indicated.
  • an aromatic primary amino developing agent e.g., a p-phenylenediamine derivative
  • Phenol couplers that are suited for producing a blue dye image or dye images having a main absorption in the red region of the visible spectrum and considerable (more than 30 percent side-absorption absorption in the green correspond to the following general formula 1 NHR RHN-
  • R represents a carboxylic acid acyl or sulphonic acid acyl group including said groups in substituted state, e.g., an aliphatic carboxylic acid acyl group, an aromatic carboxylic acid acyl group, an heterocyclic carboxylic acid acyl group, e.g., a 2-furoy1 group or a 2-thienoyl group, an aliphatic sulphonic acid acyl group, an aromatic sulphonic acid acyl group, a sulphonylthienyl group, an aryloxy-substituted aliphatic carboxylic acid acyl group, a phenylcarbamyl aliphatic carboxylic acid acyl group, or a tolyl carboxylic acid acyl group.
  • a carboxylic acid acyl or sulphonic acid acyl group including said groups in substituted state e.g., an aliphatic carboxylic acid acyl group, an aromatic carboxylic
  • silver h'alide recording materials can be used that contain two silver halide emulsions wherein a negative and a positive image are produced respectively.
  • the production of negative color images proceeds preferably according to the generally known technique of a color forming development reaction by mean of color couplers as described e.g., by W.A. Schmidt Vsevolod Tulagin, J.S.Sprung, R.C. Gunther, R.F.Coles, and D.E.Sargent in lnd.Eng.Chem. (Aug. 1953), p. 1726-1729.
  • a first technique is based on the local destruction of dyes in contact with a silver image.
  • the principles of such method and practically useful embodiments are described by P.Glafkides in Photographic Chemistry, Vol. II (1960) p. 643-646 and in the published Dutch Patent application No. 6610353 filed July 22, 1966 by Gevaert-Agfa N.V.
  • azodyes are used as bleachable compounds, e.g., the dyes Diamine Pure Blue FF, Mordant Yellow 66, Diamine Fast Pink BBF, Chrysophenine G, and Superanol Brilliant Red 3B in a concentration of 0.6 to
  • the azodyes are much more stable to light and heat than the azomethine, and quinoneimine dyes of the negative color process.
  • the destruction may be activated by bromide ions or thiourea, and is considerably accelerated .by the combined use of thiourea and catalysts known as azines.
  • the following compounds are useful representatives of the latter class 1. /N ⁇ CH3 3.
  • S OaI'I MIN-[j The third compound is preferably added to the black-and-white developing composition so that it is already present in the emulsion layer at the moment of bleaching.
  • the silver dye bleach process is mainly intended for producing a positive color image starting from a negative silver image, it can be applied equally well in a method wherein in respect of the original a positive silver image is produced, e.g., according to a process known as a black-and-white reversal processing, e.g., as described in the U.S. Pat. specification No. 2,759,824 of Ralph B.Atkinson issued Aug. 21, 1956, or by application of the bromide ion diffusion process described, e.g., in the U.K. Pat. specifications No. 690,997 filed Oct. 21, 1949 by Wegriken Bayer and 753,189 filed Sept. 14, 1954 by Agfa A.G.
  • a positive black-and-white silver image may also be produced by the photographic process known as photosolubilization process" described, e.g., in the U.S. Patent specifications Nos. 3,155,506 3,155,507 3,155,514 3,155,516 3,155,517 3,155,518 and 3,155,519 all of Ralph Kingsley Blake, issued Nov. 3, 1964.
  • a direct-positive silver image which is applicable e.g., to silver dye bleaching can be produced by means of special silver halide emulsions that are described e.g., in the published U.l(. Pat. specifications No. 1,151,363 filed Apr. 30, 1965 and 1,150,553 filed Apr. 30, 1965 both by Gevaert-Agfa N.V., and the French Pat. specifications 1,541,559 and 1,541,561 both filed Oct. 23, 1967 by Gevaert-Agfa N.V.
  • the silver halide emulsions used in that direct-positive process are of the type wherein mainly an internal latent image and to a minor extent external latent image is formed.
  • Such special silver halide emulsions are generally not or only slightly chemically ripened silver halide emulsions, since the ability of forming surface latent image increases with the degree of chemical ripening.
  • Silver chlorobromide emulsions comprising at least 20 mol. percent of silver bromide and pure silver bromide emulsions have proved to be very suitable. When these emulsions comprise a certain amount of silver iodide, often not more than 5 mole percent relative to the total amount of silver halide, they are just as well suitable. Washed as well as unwashed silver halide emulsions may be used.
  • the information-wise exposure may be either a direct or indirect exposure.
  • the exposed recording material is developed with an energetic surface developer, e.g., by conducting the material through a tray containing such developer, by means of a lick-roller, by spraying or by rubbing.
  • the developer may be more or less viscous. It must be a surface developer, i.e., a developer that contains no or at least no effective amount of solvents for silver halide.
  • solvents for silver halide particularly strong solvents for silver halide such as water-soluble thiocyanates, thiosulphates, ammonia, etc. are meant. Indeed, compounds, that may be considered as but very weak solvents for silver halide, such as sodium sulphite for the case the silver halide is silver bromide, silver chlorobromide or silver bromoiodide, may be present in the developer.
  • the light-sensitive material is exposed uniformly to actinic light of low intensity while the image-wise exposed light-sensitive layer is present in the developer or is moistened therewith in some other way.
  • This overall exposure may begin simultaneously with the treatment of the light-sensitive material with developer but preferably occurs somewhat later, e.g., from 5 to 30 seconds later.
  • the duration of the said secondary or overall exposure is not very critical and may vary between 10 seconds and several minutes according to the nature of the light-sensitive material, the composition and the temperature of the developer, the intensity of the lightsource employed, etc. In many cases the said overall exposure lasts as long as the development. Thisoffers the additional advantage that one can follow the development and stop it when the direct positive image is thought to have reached a sufficient density.
  • the density of the direct positive image can be made more intense or be reduced locally during the said second or overall exposure by the well known technique of burning in and dodging.
  • the uniformity of said overall exposure to actinic light of low intensity is mostly achieved by interposing between the lightsource and the light-sensitive material to be exposed a light-diffusing member that transmits at least part of the light rays of the spectral region to which the lightsensitive material is sensitive.
  • the required low intensity of the light rays, which reach the light-sensitive material can be obtained by adapting the light-source and/or the light-diffusing member.
  • At least one fogging agent selected from hydrazine, carbazic acid, bicarbamic ac id and/or at least one water-soluble salt thereof may be added to the energetic surface developer and/or to a preceding processing liquid for the light-sensitive recording material.
  • These fogging agents cause the formation of a latent direct-positive image that will be developable by the energetic surface developer.
  • the fogging agent(s) added to the developer itself.
  • another processing liquid incorporating the fogging agent(s) this liquid is preferably employed just before the development step.
  • the pH of the liquid to which the fogging agent has been added is preferably fairly high and in most cases amounts to at least about 10.
  • a preceding separate processing liquid containing the fogging agent(s) may comprise other ingredients such as one or more of the ingredients that otherwise are incorporated into the developer.
  • the fogging agent is added to the processing I liquid in an amount varying between about 1 g and about 50 g, preferably between 5 g and 20 g per liter.
  • the maximum density of the direct positive image may be increased by carrying out the development in the presence of a compound setting free iodide ions in an aqueous medium and/or a compound setting free bromide ions in an aqueous medium.
  • a compound setting free iodide ions in an aqueous medium and/or a compound setting free bromide ions in an aqueous medium.
  • watersoluble iodides such as potassium iodide, are very suited for this purpose.
  • the minimum density of the direct positive image can be lowered by incorporating a fog-inhibiting compound into the light-sensitive recording material.
  • This fog-inhibiting compound must be present in effective contact with the silver halide emulsion layer.
  • effective contact is meant that the fog-inhibiting compound is provided in the light-sensitive recording material on a place from which it can act upon the silver halide emulsion layer at the appropriate moment, in this case during the soaking of the light-sensitive material with the developer.
  • the fog-inhibiting compound is preferably incorporated into the silver halide emulsion layer itself, but may also be present in an other water-permeable non-light-sensitive layer of the light-sensitive material such as a covering layer or an intermediate layer, from which it is dissolved by the developer liquid and diffuses to the light-sensitive layer. It is even possible to incorporate considerable amounts of the fog-inhibiting compound into the developer liquid.
  • the fog-inhibiting compounds give rise to a lowering of the minimum density of the direct-positive image even when present only in small amounts. They are sufficiently efficient when applied in the common fog-inhibiting amounts. The best results i.e., the most clear minimum densities are attained, however, when using the fog-inhibiting compounds in amounts larger than the common fog-inhibiting amounts i.e., in amounts that normally are not applied to light-sensitive materials since they would desensitize the light-sensitive material too much. Suprisingly, these large amounts of fog-inhibiting compound do not lower the direct-positive image sensitivity of the light-sensitive recording material but in most cases even enhance it and also do not prevent the formation of a direct-positive image with good maximum density. Specific data about the concentrations in which the fog-inhibiting compounds are generally employed and yield optimal results can hardly be given since according to the nature of the fog-inhibiting compound and the kind of silver halide emulsion layer used they are widely divergent.
  • a photographic direct positive color image may be produced by a process including the following steps imagewise exposing a recording material containing a light-sensitive silver halide wherein mainly internal latent image and little external latent image is formed, developing the light-sensitive material thus exposed with an energetic surface developer in the presence of a color coupler forming a dye with the oxidized developing agent, and overall-exposing the lightsensitive material during the developing stage to actinic light of low intensity, and/or carrying out the said development in the presence of a suitable fogging agent.
  • a photographic element comprising at least one water-permeable layer which contains radiation sensitive silver halide grains, in effective contact with these grains a color coupler capable of forming on development an azomethine or quinoneimine dye which by treatment with an acidic solution, the hydrogen ion concentration of which is at least 10' gram-equivalent per liter, can be transformed in colorless products, and in effective contact with said color coupler a compound capable of forming an acid-resistant dye by oxidative coupling with said color coupler,
  • a colored direct positive image can also be produced by means of a process using compounds that react with the oxidation product of a developing agent to form therewith colorless products in the exposed parts of a silver halide emulsion layer. These compounds possess preferably themselves no developing activity and do not react with the oxidation products of the developing agent(s) or only react therewith to form colorless substances. 7
  • the amidrazones are compounds containing the structural group Vinylene homologues, phenylene homologues and azavinylene homologues are those which contain a vinylene group, a phenylene group or an azomethine group in the above structural group between the carbon atom and thereto singly bonded nitrogen atom.
  • Said process for the production of direct-positive dye images more particularly includes the steps of a. image-wise exposing a photographic material, which contains at least one silver halide emulsion layer containing an effective amount of a compound capable of reacting with the oxidation products of photographic color developers to form colorless products,
  • the oxidizing bleaching being performed in effective contact with such compounds that are capable of reacting with developer oxidation products to form substances which are colorless at the end of the photographic processing and being performed in effective contact with amidrazones, vinylene homologues of the amidrazones and azavinylene homologues of the amidrazones allowing said compounds to react with the oxidation products of the amidrazones to form colored products.
  • the compounds that are used to react with the oxidation products of the amidrazones to form colored products are preferably selected from the group consisting of arylamines, compounds of the 5-amino-A-2- pyrazoline series and compounds of'the l-phenyl-A-Z- pyrazolone series.
  • amidrazones mentioned therein are also suited for the formation of a positive dye image by, oxidative copulation with color couplers of the phenol, anaphthol and pyrazolone type that remained after color development in the non-exposed silver halide emulsion portions (see therefor e.g., the U.S. Pat. spec. No. 3,245,788 and 3,245,787).
  • the conventional method can be applied, which comprises the consecutive steps of image-wise exposing a lightsensitive silver halide reversal material, developing the exposed silver halide in a black-and-white developing composition, rinsing, re-exposing the material uniformly to actinic light so as to form a latent image in the residual silver halide, developing said latent image in a color developing composition, and bleaching, rinsing and drying the material.
  • the second exposure can be omitted if the material is treated in a solution of a fogging agent such as hydrazine or a semi-carbazide, e.g., 10 g of semicarbazide hydrochloride per liter.
  • the fogging agent may be added directly to the second developer.
  • Negative and positive color images can also be produced in the same recording material by means of a process based on the image-wise diffusion of compounds such as complexed silver salts.
  • the silver halide complex diffusion transfer is applied in order to obtain a negative and positive silver image in different layers of a same recording material. Therefore, a-
  • recording material contains a layer which comprises development nuclei appliedin a layer onto or under the silver halide emulsion layer e.g., onto the support of a silver halide emulsion layer.
  • the silver halide emulsion layer contains a bleachable dye, e.g., a blue azo dye, and in or onto the development nuclei-containing layer or sheet a bleachable yellow dye.
  • a bleachable dye e.g., a blue azo dye
  • the silver halide emulsion layer contains a bleachable dye, e.g., a blue azo dye, and in or onto the development nuclei-containing layer or sheet a bleachable yellow dye.
  • Positive and negative color images of contrasting colors can also be obtained according to an embodiment based on the diffusion transfer of colored developing agents, in the same recording material.
  • a colored developing agent can be applied in a colloid layer beneath a silver halide emulsion or in the emulsion layer itself, which layer contains a dye e.g., a blue azo dye that can be bleached with the aid of silver.
  • the colored developing agent e.g., yellow developing agent, is of the hydroquinone type being alkali-soluble in non-oxidized state and may contain a chromophoric group that is less sensitive for bleaching in the presence of silver than the azo dye present in the emulsion layer.
  • Suitable colored developing agents for that purpose are described in the Canadian Pat. specification No. 598,786 filed Apr. 1, 1959 by Polaroid and the U.S. Pat. No.
  • a colored negative and positive image of opposite gradation can be produced in a receiving material by means of a recording material, which is built up, e.g., in the following way:
  • the latter which are not fixed (i.e. which have not been made resistant to diffusion in the quinone form) are transferred by means of the alkaline processing solution from the non-silver image areas to a receptor layer or sheet, e.g. paper or film, coated with, a colloid layer and optionally absorbed thereon with the aid of mordanting agent.
  • a receptor layer or sheet e.g. paper or film, coated with, a colloid layer and optionally absorbed thereon with the aid of mordanting agent.
  • Self-explanatory after bleaching the silver images in the recording material a bi-color image of opposite gradation will be left therein.
  • the silver dye bleach process it is possible to use a combination of separate silver halide emulsions which yield a negative and a positive image respectively by a proper exposure and development.
  • the said emulsions are applied to opposite sides of a light-transmitting film support, which during a direct exposure with penetrating rays may be opaque or coated with an opaque interlayer, which can be bleached or decolorized in one of the processing liquids.
  • a light-transmitting film support which during a direct exposure with penetrating rays may be opaque or coated with an opaque interlayer, which can be bleached or decolorized in one of the processing liquids.
  • An interlayer between the emulsion layers may also act as filter layer whereby one of the emulsion layers during an indirect exposure (e.g. from a fluorescing screen with phosphors emitting in the visible and/or U.V.spectrum) is exposed to light of a wavelength range, which differs from the light to which the other silver halide emulsion is exposed.
  • an indirect exposure e.g. from a fluorescing screen with phosphors emitting in the visible and/or U.V.spectrum
  • silver halide emulsions applied according to the present invention different types of silver halide can be used e.g., silver chloride, silver bromide, silver chlorobromide, silver chlorobromideiodide, silver chloroiodide or silver bromide iodide or mixtures thereof.
  • Iodide-containing bromide emulsions, preferably containing up to 10 mole percent of iodide are especially useful for directly or indirectly recording penetrating radiation.
  • silver bromide-iodide emulsions containing from 10 to 2 mole percent of iodide and corresponding with 5 to 16 g of silver nitrate per sq.m.
  • a more preferred silver halide content corresponds with 6 to 12 g of silver nitrate per sq.m.
  • the colloid binder of the silver halide preferably essentially consists of gelatin, and preferably is present in an amount of 3 to 7 g per sq.m in a single silver halide emulsion layer.
  • an amount of silver halide is used preferably in excess of 50 to percent in respect of the equivalent amount necessary in the dye forming reaction using exposed silver halide and a color developing agent of the P-phenylene diamine type.
  • color couplers are preferably incorporated in the silver halide emulsion colloid in diffusion resistant state they may be applied also in dissolved state from the developing bath.
  • the color couplers are made resistant to diffusion in hydrophilic colloid layers by techniques known in the art e.g., by the use of color coupler molecules with fairly long aliphatic carbon chains (e.g. C C or incorporation of the color couplers in droplets of high boiling organic water-immiscible liquids so-called oil-formers.
  • the support of the silver halide emulsion layers suited for use according to the present invention is preferably a transparent resin support.
  • Transparent resin supports for use in photographic silver halide materials are generally known. In common materials cellulose triacetate supports are used and where a high dimensional stability is required preferably a polyester resin support e.g., of polyethylene terephthalate is used.
  • radiographic recording materials e.g., suited for use in an exposure with fluorescing screens contain at both sides of the support a silver halide emulsion layer incorporating the necessary substances for forming the desired images contrasting in color tone (hue) and being of opposite gradation.
  • aromatic primary amino developing agents of the p-phenylene diamine type e.g., p-phenylene-diamine, N,N-diethyl-p-phenylenediamine, N-butyl-N-sulphobutyl-p-phenylenediamine, 2-amino-5-diethylaminotoluene hydrochloride and 4-amino-N-ethyl-N(B-methanesulphonamido-ethyl)-m-toluidine sesquisulphate monohydrate or N-B-hydroxyethyl-N-ethyl-p-phenylene-diamine.
  • N-butyl-N-sulphobutyl-p-phenylenediamine and/or N-B-hydroxyethyl-N-ethyl-pphenyleneadiamine are used.
  • the radiation-sensitive materials for use according to the present invention in addition to the desired color coupler may contain all kinds of ingredients characteristic for silver halide materials used for direct or indirect recording of penetrating radiation.
  • the radiation-sensitive silver halide emulsions may contain sensitizing and/or screening dyes.
  • selectively working desensitizing dyes are used which lower the sensitivity to visible light without substantially affecting the X-ray sensitivity.
  • reference is made nand Schulze, issued July 8, 1947, U.S. Pat. No.
  • organic onium compounds and polyonium compounds preferably of the ammonium or sulphonium type, e.g., quaternary tetraalkylammonium salts, alkyl-pyridinium salts, bisalkylene-pyridinium salts, alkyl-quinolinium salts, and trialkyl-sulphonium salts.
  • the silver halide can further be combined'with chemical sensitizers known in the art such as sulphurcontaining sensitizing compounds e.g., allyl isothiocyanate, allylthiourea, reducing compounds such as the tin compounds described in the Belgian Patent specifications Nos. 493,464 filed Jan. 24, 1950 and 568,687 filed June 18, 1958 both by Gevaert Photo-Producten N.V., or noble metal compounds such as gold, platinum, palladium, iridium, ruthenium and rhodium compounds.
  • chemical sensitizers known in the art such as sulphurcontaining sensitizing compounds e.g., allyl isothiocyanate, allylthiourea, reducing compounds such as the tin compounds described in the Belgian Patent specifications Nos. 493,464 filed Jan. 24, 1950 and 568,687 filed June 18, 1958 both by Gevaert Photo-Producten N.V.
  • noble metal compounds such as gold, platinum,
  • the silver halide emulsions used according to the present invention can also contain knownstabilizing agents for silver halide emulsions, e.g., mercury compounds, sulphur. compounds such as 1-phenyl-2- tetrazoline-S-thione, the compounds described in the N R3C N c-R,
  • each of R and R represents a hydrogen atom, an alkyl, an aralkyl, or an aryl group
  • R represents a hydrogen atom, an alkyl, a carboxy
  • the processing of the radiation-sensitive film used for producing color radiographs according to the present invention may occur in conventional deep-tank processors including a drier, e.g., the Gevamatic S (trade name) automatic processor for industrial X-ray films, the wet-treatment stations being provided with the appropriate liquid compositions, or in apparatus wherein the application of one or several processing liquids to the film occurs by a lick-roller, a kiss-roller, or any other system capable of applying to one side of the film only a limited and premetered quantum ,of processing composition.
  • the processing may also be carried out manually by the operator, who attaches the film to the clips of a frame which is successively dipped into the different processing'tanks.
  • the re-exposure device may be arranged to illuminate the film at one side.
  • the penetration of light into emulsion layers at the other side of the film may be prevented by dyed intermediate layers absorbing said radiation. During or after the completion of the processing the dye of said layers may be bleached or otherwise eliminated.
  • the emulsion was coated onto a cellulose triacetate support 13 in such a way that it formed onto a subbing layer 14 a yellow colored emulsion layer-117 containing per sq.m 0.6 to 9.0 g of silver in the form of silver bromide.
  • a silver bromideiodide (2 mole percent of iodide) emulsion was coated onto a subbing layer in such a way that an emulsion layer 17 was formed containing per sq.m an amount of silver halide corresponding with 9 g of silver nitrate and an amount of 1.5 g of a colorless cyan-forming coupler according to the following formula OH C1 melting point 1 108C.
  • the emulsion layers were covered with antistress layers 18.
  • the recording material 12 was image-wise exposed as illustrated in FIG. 3 by means of an X-ray radiation source 10, the radiation source 10, the radiation of which was image-wise transmitted through the original 11 representing a cast metal part of a machine.
  • the film was developed with a p-phenylenediamine type developing agent. On both sides of the support a silver image was formed. A cyan image was only formed in the emulsion layer 15 containing the cyan-forming color coupler. Thereupon both emulsion layers were fixed and rinsed.
  • the azo-dye was image-wise destroyed and the silver was bleached in the emulsion layer 17 by means of a liquid having the following composition potassium iodide g sodium hypophosphite 10 g sulphuric acid 66 Be 50 ml quinoline 50 ml 2,3-dimethylquinoxaline 20 mg water 1,000 ccs
  • the bleaching liquid was applied by means of a spraying device only moistening the film side carrying the azo-dye. After a working contact of 25 min. the film was rinsed and the residual silver was completely bleached by means of a solution consisting of:
  • composition of the radiographic color image obtained is shown in Fig. 4.
  • the layer contained a negative cyan image of the original which image is indicated in the layer 15 by the shaded portion.
  • the layer 17 contained a positive yellow image of the original 11.
  • the shaded portions of said layer are yellow because in these areas the yellow azo-dye remained unaffected.
  • the light box on which the radiograph was examined was provided with a light yellow filter in the form of a cellulose triacetate support provided with a yellow gelatin layer.
  • a light yellow filter in the form of a cellulose triacetate support provided with a yellow gelatin layer.
  • the contrast of the cyan parts of the image and particularly those of low densities, say from 0.05 to 0.03, corresponding e.g., with fissures and other defects in the radiographed metal part, was increased whereas that of the yellow parts of the image was reduced.
  • the emulsion was coated as illustrated in FIG. 5 in such a way onto a polyethylene terephthalate support 20 carrying subbing layers 21 and 22 that it contained in the dried layer 25 an amount of silver halide corresponding with 0.8 g of silver per sq.m.
  • emulsion layers 23 and 24 were coated. Both emulsion layers were of the negative type.
  • the emulsion layers 23 and 24 contained an amount of silver halide corresponding with 8 g of silver nitrate per sq.m.
  • Emulsion layer 23 contained in addition per sq.m.
  • the emulsion layer 24 contained a yellow-forming color coupler having the following formula SOaH Melting point 250C, prepared as described in Belgian Pat. specification No. 725,904 filed Dec. 23, 1968 by Gevaert-Agfa N.V. (preparation 3).
  • the described radiographic film was image-wise exposed to the object 11 of FIG. 3 and thereupon processed as described in Example 1.
  • the radiographic image obtained was composed as illustrated in FIG. 6.
  • the layer 23 contained a negative magenta image of the object 11 of FIG. 3, as indicated by the shaded portion.
  • the layer 24 contained a negative yellow image of the object 11, indicated by the shaded portion.
  • the layer 25 contained a positive cyan image of the original. At the non-shaded portion the cyan dye has been destroyed in proportion to the amount of silver present.
  • composition of the film material described may be changed without changing the color rendering of the image.
  • the layers 23 and 24- may be replaced by one layer containing yellow forming as well as magenta-forming color couplers.
  • EXAMPLE 3 In FIG. 7 a cellulose triacetate support 30 having subbing layers 31 and 32, was coated at one side of the support with a silver bromide emulsion layer 33 of the negative type containing a bleachable cyan azo-dye, as described in Example 2 and at the other side of the support with a silver halide emulsion layer 34 of the direct positive type as described in the published U.K. Pat.
  • the radiographic film was image-wise exposed to the original 11 as illustrated in FIG. 3 and black-and-white developed in order to obtain a negative and positive silver image in the yellow and cyan emulsion layers respectively.
  • the bleaching of the azo-dyes was carried out as described in Example 1 and a positive cyan and negative yellow image of opposite gradation were obtained in the same recording material as represented by the shaded areas in the layers 33 and 34 of FIG. 8.
  • EXAMPLE 4 One-hundred g of a. silver bromide-iodide (9 mole percent of iodide) emulsion were diluted with 100 cos of water, 13 ccs of 0.5 N aqueous succinic acid and ccs of 1 percent aqueous saponine solution.
  • The, light-sensitive material was developed in a developing liquid having the following composition 2 CONH N,N-diethyl-p-phenylenediamine 3 g sulphate sodium sulphite 4 g sodium carbonate 50 g potassium bromide l g hydroxylamine-hydrochloride 1.5 g water 1000 ccs A blue negative wedge print was obtained. The absorption maximum of the dye was at 625 mu.
  • the developed silver image was bleached for 3 min. in an alkaline bleaching bath having the following composition sodium hydrogen sulphate 4 g borax 20 g potassium bromide 15 g potassium hexacyanoferrate (III) 100 g water 1000 ccs.
  • the purified precipitate was dried in a cold ventilated drying oven. Yield 220 g (89 percent). Melting point: beyond 260C.
  • the concentrated reaction mixture was then poured on about 6 kg of ice mixed with 750 ml of concentrated hydrochloric acid. As soon as the precipitate was solid, it was filtered with suction, washed with water and dried. First it was recrystallized from about 4.5 liter of ethanol and then from about 1.7 liter of dichloroethane.
  • EXAMPLE A polyester resin support provided at both sides with 5 subbing layers for gelatin coatings was coated on both sides with a silver bromide-iodide emulsion (3mole percent of iodide). Eachdried emulsion layer contained per sq.m an amount of silver halide corresponding with 9 g of silver nitrate, 4.5 g of a red colored color coupler having the following structural formula (HI s 0 H N-CH; lisHav N l H3CC O-NH and forming a cyan dye on copulation with an oxidized p-phenylenediamine type developing agent, and 4 g of a colorless cyan-forming color coupler having the following structural formula @ficmmcm QsH 7 (prepared according to Fiat Final Report 943 p. 68).
  • This diazonium salt solution was dropwise added to a solution of 18.5 g of l-hydroxy-2'(N-methyl-N-n-octadecylamino)-5'-sulpho-2-naphthanilide in 300 ml of methanol, while an amount of sodium hydroxide solution was added necessary to keep the pH at 8-9. Thereupon the mixture was stirred for another 2 hours, whereafter the dye precipitated was filtered with suction, washed with methanol and dried under reduced pressure. The red dye obtained possessed an absorption maximum at 462 nm in gelatin.
  • Example 4 was repeated but instead of the therein described blue-forming color coupler the recording material contained the blue-forming color coupler having the following structure COOH Melting point 174C.
  • a blue negative image having an absorption maximum at 615 nm and a yellow positive image (absorption maximum at 436 nm) were obtained.
  • Example 4 was repeated but the cited blue-forming color coupler in the recording material was replaced by the blue-forming color coupler P having the formula CONH melting point 156C. (Prepared analogously to the color coupler of Example 4).
  • a blue negative image (absorption maximum 610 nm) and a red positive image (absorption maximum 523 nm) were obtained in the emulsion layer.
  • EXAMPLE 8 A first silver halide emulsion layer was coated onto one side of a cellulose triacetate base.
  • the said emulsion layer contained per sq.m 0.01 mole of silver halide consisting of 0.5 mole percent of iodide, 72.5 mole percent of bromide and 27 mole percent of chloride as well as 1.35 g of magenta-forming color coupler A having the formula:
  • a second silver halide emulsion layer was applied to the other side of the cellulose triacetate base. It contained per sq.m 0.09 mole of silver halide consisting of 2 mole percent of iodide and 98 mole percent of bromide as well as 0.8 g of cyan-forming color coupler B having the formula OaNB

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4131464A (en) * 1976-07-08 1978-12-26 Avrum Silverman False color photographic element and process
US6124242A (en) * 1998-06-26 2000-09-26 Basf Aktiengesellschaft Herbicidal compositions and processes based on ferrodoxin:NADP reductase inhibitors
WO2006032173A1 (fr) * 2004-09-20 2006-03-30 Institute Of Pharmacology And Toxicology Academy Of Military Medical Sciences P.L.A. China Composés hydrazides aryliques et utilisation de ceux-ci dans la préparation d'un agent immunodépresseur
US20240093082A1 (en) * 2022-09-09 2024-03-21 Saudi Arabian Oil Company Aqueous fluid compositions and barite scale removal therewith

Families Citing this family (3)

* Cited by examiner, † Cited by third party
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GB1378171A (en) * 1971-01-05 1974-12-27 Agfa Gevaert Process for producing photogrpahic silver images
JPH0727184B2 (ja) * 1986-10-27 1995-03-29 富士写真フイルム株式会社 直接ポジカラー画像形成方法
PT4426434T (pt) 2021-11-02 2025-11-24 Flare Therapeutics Inc Agonistas inversos de pparg e suas utilizações

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2644096A (en) * 1948-02-25 1953-06-30 Radiograph Dev Corp Color radiography
US2772162A (en) * 1954-11-03 1956-11-27 Eastman Kodak Co Diacylaminophenol couplers
US2931904A (en) * 1953-12-28 1960-04-05 Bernard M Fine Color radiographs, methods and articles
US3114833A (en) * 1948-02-25 1963-12-17 Bernard M Fine Multicolor radiography
US3121232A (en) * 1954-12-15 1964-02-11 United States Radium Corp Color radiographic film
US3222176A (en) * 1960-10-04 1965-12-07 Gevaert Photo Prod Nv Photographic colour images from amino substituted phenols
US3351466A (en) * 1961-05-29 1967-11-07 Polaroid Corp Radiographs viewable by reflected or transmitted light

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2644096A (en) * 1948-02-25 1953-06-30 Radiograph Dev Corp Color radiography
US3114833A (en) * 1948-02-25 1963-12-17 Bernard M Fine Multicolor radiography
US2931904A (en) * 1953-12-28 1960-04-05 Bernard M Fine Color radiographs, methods and articles
US2772162A (en) * 1954-11-03 1956-11-27 Eastman Kodak Co Diacylaminophenol couplers
US3121232A (en) * 1954-12-15 1964-02-11 United States Radium Corp Color radiographic film
US3222176A (en) * 1960-10-04 1965-12-07 Gevaert Photo Prod Nv Photographic colour images from amino substituted phenols
US3351466A (en) * 1961-05-29 1967-11-07 Polaroid Corp Radiographs viewable by reflected or transmitted light

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4131464A (en) * 1976-07-08 1978-12-26 Avrum Silverman False color photographic element and process
US6124242A (en) * 1998-06-26 2000-09-26 Basf Aktiengesellschaft Herbicidal compositions and processes based on ferrodoxin:NADP reductase inhibitors
WO2006032173A1 (fr) * 2004-09-20 2006-03-30 Institute Of Pharmacology And Toxicology Academy Of Military Medical Sciences P.L.A. China Composés hydrazides aryliques et utilisation de ceux-ci dans la préparation d'un agent immunodépresseur
US20240093082A1 (en) * 2022-09-09 2024-03-21 Saudi Arabian Oil Company Aqueous fluid compositions and barite scale removal therewith
US12227693B2 (en) * 2022-09-09 2025-02-18 Saudi Arabian Oil Company Aqueous fluid compositions and barite scale removal therewith

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