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
  • 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
  • G03C7/3003—Materials characterised by the use of combinations of photographic compounds known as such, or by a particular location in the photographic element
• • 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
  • 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
  • G03C7/3029—Materials characterised by a specific arrangement of layers, e.g. unit layers, or layers having a specific function
  • G03C2007/3034—Unit 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
  • 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
  • G03C7/305—Substances liberating photographically active agents, e.g. development-inhibiting releasing couplers
  • G03C7/30541—Substances liberating photographically active agents, e.g. development-inhibiting releasing couplers characterised by the released group

Definitions

• Photographic elements are provided which feature a support having coated thereon a first photographic silver halide emulsion layer containing image-forming coupler and development inhibitor-releasing coupler; and, a second silver halide emulsion layer containing photographic image forming coupler, the second layer having a faster effective speed sensitivity than the first layer.
• Such elements have high contrast for faint images and an extended latitude of low contrast for bright images.
• PI-IOTOGRAPI-IIC ELEMENT INCLUDING SUPERIMPOSED SILVER HALIDE LAYERS OF DIFFERENT SPEEDS
• This invention relates to photographic elements, and more particularly to the photographic elements having wide exposure latitudes.
• Photographic elements having wide exposure latitudes have previously been provided by coating fast and slow silver halide emulsion layers onto a support See, for example, Beach British Patent 774,655 (published 1957) and Millikan British Patent 1,021,564 (published 1966). While such elements are highly useful for the purposes intended, they exhibit deficiencies when utilized in certain applications. In some instances, it is desirable to provide photographic elements having a high contrast for faint images and a long latitude of low contrast for bright images. Such elements would record images of vastly different intensities without the stronger image flaring' or spreading so much that it obliterates the fainter image.
• the prior art fails to teach how to obtain a photographic element which produces high contrast and high speed for faint images and low contrast with extended latitude for bright images.
• Prior art films have utterly failed in satisfactorily recording the faint image produced upon initial entry of an orbiting satellite into the earth's atmosphere.
• the image of the faint satellite upon initial reentry could not be measured because its image was obliterated by the flare produced by the stronger image of the burning satellite in the lower atmosphere.
• the amount of flare produced by the stronger image of the burning satellite has been used to measure indirectly the path and brightness of the satellite on initial stages of reentry.
• One object of this invention is to provide novel photo graphic elements which have wide exposure latitude.
• Another object of this invention is to provide photographic elements which exhibit low image spread over the useful expo sure latitude.
• a further object of this invention is to provide photographic elements which exhibit high contrast when exposed to faint images; and, low contrast and wide latitude when exposed to bright images having a dark background.
• novel photographic elements comprising a support having coated thereon a first photographic silver halide emulsion layer containing (l) nondiffusible photographic coupler which forms image dye and (2) a development inhibitor-releasing coupler; and, a second photographic silver halide emulsion layer containing nondiffusible photographic coupler which forms image dye, said second layer having a faster effective speed sensitivity than said first layer.
• the development inhibitor-releasing coupler in the slower image-recording layer effectively extends exposure latitude and reduces contrast.
• Such photographic elements have wide exposure latitude, and are capable of recording images of vastly different intensity in close geometrical proximity with minimal image spread.
• Photographic elements in accordance with this invention exhibit excellent sharpness. They produce high-contrast records of faint images and low-contrast records of bright images.
• a photographic element is provided as described above which contains a nonimage-forming, light-diffusing silver halide emulsion layer positioned between the support and the silver halide emulsion layers. Photographic elements in accordance with this embodiment of the invention exhibit reduced image spread.
• an antihalation layer is provided between the support and the image recording layers
• the fast and slow silver halide emulsion image recording 0 layers utilized in the photographic elements of this invention can comprise any suitable silver halide, such as silver bromide, silver iodide, silver chloride, or mixed halides such as silver bromoiodide or silver chlorobromide.
• the silver halide grains in the image-recording layers can be spectrally sensitized, for example when it is desired to expose the elements to radiation longer than blue radiation.
• the silver halide grains of each image-recording layer are panchromatically sensitized. Any of the dyes suggested in the prior art for spectrally sensitizing silver halide can be used in the practice of this invention.
• the silver halide grains used in the image recording layers are advantageously negative, developing-out silver halide grains.
• the optimum speeds of the image-recording layers will depend upon the various uses to which the elements are put. Preferably, the speed sensitivity of the two layers overlaps. Good results are obtained when the effective speed of the slower image-recording layer is about 0.6 Log E to about 1.2 Log E slower than the fast image-recording layer. It is desirable that the faster silver halide emulsion layer have a detection capability in the region of about 5 quanta per square micron.
• the elements exhibit an exposure latitude of about 10 over the reliable exposure latitude.
• the effective speeds of the emulsion layers can be regulated in any convenient manner, such as by use of silver halides of different grain size, chemical sensitizcrs, concentration of photographic coupler, etc.
• the fast and slow image-recording layers can be contiguous. Either the slow or the fast imagc-recording layers may be coated closest to the support, with the other emulsion layer coated thereover. In preferred embodiments, the slower emulsion layer is coated closest to the support, with the fast emulsion layer being coated thereover.
• photographic image-forming coupler is used herein as a word of art and includes organic compounds which react with oxidized primary aromatic amine developing agents to form dye images.
• the photographic image-forming couplers, as well as the development inhibitor-releasing couplers which are utilized in the practice of this invention can embody any photographic coupler radical.
• Typical useful photographic coupler radicals include the S-pyrazolone coupler radicals, the phenolic (including a-naphthol)coupler radicals, and the open-chain ketomethylene coupler radicals.
• 5 pyrazolone coupler radicals are customarily utilized for the formation of magenta dyes; phenolic coupler radicals are generally utilized for the formation of cyan color dyes; and, open-chain ketomethylene coupler radicals are generally utilized in the formation of yellow dyes.
• the coupling position of such coupler radicals is also well known in the art.
• the S-pyrazolone coupler radicals couple at the carbon atom in the 4-position thereof; the phenolic coupler radicals couple at the carbon atom in the 4-position (relative to the hydroxyl group); and, the open-chain ketomethylene coupler radicals couple at the carbon atom forming the methylene moiety (e.g.,
• R X and Y represent substituents of the type used in open-chain ketomethylene couplers.
• R can represent an alkyl group (which can be substituted and preferably has from about six to 22 carbon atoms); an aryl group (preferably a phenyl or naphthyl group); or, a heterocyclic group (preferably a carbon containing heterocyclic radical which contains from five to six atoms in the heterocyclic ring, which ring contains at least one hetero-oxygen sulfur or nitrogen atom);
• X can represent'a member selected from the group consisting of cyano and carbamyl (which can be substituted); and, Y can' have a meaning given below for the image forming and development inhibitor-releasing couplers utilized herein.
• the image forming and the development inhibitor-releasing couplers utilized in this invention can feature a S-pyrazolone coupler radical having the following general formula:
• R R and Y represent substituents of the type used in S-pyrazolone couplers, for example, R, can represent a value given for R,;
• R can represent a member selected from the group consisting of an alkyl group, a carbamyl group (which can be substituted), an amino group (which can be substituted with various groups such as one or two alkyl or aryl groups), an amido group, e.g., a benzamido group (which can be substituted), or an alkylamido group (which can be substituted), and, Y; can represent a value given below for the image forming and the development inhibitor-releasing couplers utilized herein.
• the photographic image forming and development inhibitor-releasing couplers employed in the practice of this invention can utilize any suitable phenolic (including alphanaphtholic) coupler radicals, including those described in the structural formula below:
• R R R R and Y can represent a substituent of the type used in phenolic couplers, for example, R and R each can represent a value given for R,, and in addition can represent a member selected from the group consisting of hydrogen, amino, carbonamido, sulfonamido, sulfamyl, carbamyl, halogen and alkoxy; R and R,,, when taken together, can represent the carbon atoms necessary to complete a benzo group, which benzo group can be substituted with any of the groups given for R and R and, when taken separately, R and R can each independently represent a value given for R and R and, Y represents a value given below for the image forming and development inhibitor-releasing couplers utilized herein.
• the useful image-forming couplers include both the fourequivalent and two-equivalent nondiffusing couplers.
• Typical useful four-equivalent yellow dye-forming couplers which can be utilized in this invention include the following:
• N-amyl-p-benzoylacetaminobenzenesulfonate 2.
• Typical useful two-equivalent yellow-forming opcnchain ketomethylene couplers include the following:
• lncluded among the coupling off groups are the acyloxy group illustrated by the 4-acyloxyphenols and 4-acyloxynaphthols of Loria U.S. Pat. No. 3,31 1,476, issued Mar. 28, 1967, the cyclooxy group illustrated by the 4-cyclooxy naphthols of Loria U.S. Pat. application 483,807, filed Aug. 30, 1965, the thiocyano group illustrated by the 4-thiophenols and 4-thionaphthols of Loria U.S. Pat. No. 3,253,294, the cyclic imido groups as illustrated by the 4-cyclie imido derivatives of I-hydrogen-Z-naphthamides of Loria U.S. Pat.
• Typical two-equivalent cyan-forming couplers which can be used in this invention include the following:
• the photographic image-forming coupler is used at a sufficient concentration to give a dye image of suitable density. The concentration employed will depend on the characteristics of the dye formed by the coupler, and on the nature of the photographic emulsion in which it is incorporated.
• the photographic image-forming coupler preferably is nondiffusible, and colorless.
• It can be a coupler of the type which forms a diffusible dye image (which can be transferred to a suitable receiving sheet) or a type which forms nondiffusible dye images.
• the invention is useful with all photographic incorporated image forming couplers which form dye images by imagewise reaction with oxidizing primary aromatic amine color-developing agent.
• Incorporated refers to silver halide emulsion layers containing photographic image-forming couplers at the time of exposure.
• Photographic couplers which form cyan dye images are especially useful in the practice of this invention. However, couplers which form other colored images, such as magenta or yellow dye images, can also be utilized with good results.
• the couplers utilized in the image-recording layers can produce dyes of essentially the same color or they can have incorporated therein photographic couplers which produce different dye images.
• development inhibitor-releasing coupler is used herein as a word of art to refer to those photographic couplers which, upon reaction with oxidized primary aromatic amine color-developing agent, form dye and release a compound which inhibits development.
• Development inhibitor-releasing (DIR) couplers which can be utilized herein can be represented by the general formula:
• C represents a photographic coupler radical, preferably an open-chain ketomethylene, S-pyrazolone or phenolic (including alpha-naphtholic) coupler radicals, having said Z substituted in the coupling position of the coupler radical, Z representing an organic group which does not contain a chromophore, does not couple with oxidized primary aromatic amine color developer to form dye, does not inhibit development while attached to Cp, but is released from Cp, on reaction with oxidized primary aromatic amine color-developing agent, and either is or forms a compound which inhibits development.
• Especially useful DlR couplers have Formula I, II or lll above, wherein Y,, Y and Y: each are selected from:
• a 2-aminoarylazoxy group e.g., 2-amino-4-methyl-phenylazoxy, 2-aminophenylazoxy, 2-amino-4-chlorphenylazoxy, etc.
• a Z-amidoarylazoxy group e.g., 2-acetamidophenylazoxy, 2-acetamido-4-methylphenylazoxy, 2-acetamido- 4-chlorophenylazoxy, 2-palmitamidophenylazoxy, 4- methoxy-2-palmitamidophenylazoxy,4-chloro-2-palmitamidophenyl-azoxy, etc.
• the Z group (or Y,, Y and Y in the above formulas) (1) forms a diffusible mercaptan and (2), (3) and (4) form a diffusible aryltriazole upon reaction with oxidized color developing agent.
• DlR couplers include the following: 1 a-BenZoyl-a-( 2nitrophenylthio)-4-[ Nw -phenyll0. u-(6-Chloro-5-methoity-2-benzotriazolyl )-a-pivalyl- 2-chloro-5-[ a-( 3-pentadecyl-4-sulfophenoxy )-butyramido1acetanilide, sodium salt 1 l. l-Phenyl-3-octadecylamino-4-[ 2-phenyl-5-( 1,3 ,4)-
• Couplers 6, 7, 28 and 41 are prepared by methods similar to those disclosed in "U.S. Pat. No. 3,148,062. Couplers 8 through 10, 29 through 32 and 42 through 45 are described by Sawdey U.S. Pat. application Ser. No. 674,090, filed Oct. [0, i967. The couplers referred to in the immediate paragraph are the DIR couplers listed above.
• the most useful DIR couplers are those which have a monothio group in the coupling position (e.g., Formula I, ll and ill above in which Y Y and Y represent a monothio group).
• Preferred DIR couplers have Formula I, ll or ill above wherein Y,, Y and Y each represents a heterocyclic monothio radical in which the heterocyclic ring has from five to six atoms and at least one hetero atom selected from oxygen, sulfur and nitrogen, such as a hetero ring, containing from one to four heteronitrogen atoms, e.g., a S-tetrazolylthio group.
• a DlR coupler is selected which forms a dye of substantially the same color as the dye formed by the image forming coupler.
• the development inhibitor-releasing coupler is used at a concentration sufficient to effectively provide the desired extended latitude low-contrast shoulder.
• concentration of the development inhibitor-releasing coupler will depend on whether a nonimage-forming silver halide layer is utilized contiguous to the slow silver halide emulsion layer, as well as upon the characteristics of the silver halide emulsion layer, the development inhibitor-releasing coupler itself and other variables. As a general guideline, good results can be obtained when about i to 50 mg. per square foot of development inhibitor-releasing coupler are utilized.
• the fast emulsion layer is free from DIR coupler.
• a nonimage-forming hydrophilic colloid silver halide layer can be utilized in the elements of this invention intermediate the support and the image-recording silver halide emulsion layers.
• the nonimage-recording silver halide emulsion layer comprises silver halide grains which have an average diameter of about 0.1 to about 1 micron.
• This relatively fine grained emulsion can be coated at various thicknesses, as from about 10 to 40 microns, to reduce image spread. Utilization of such layers to reduce image spread is described and claimed in Millikan U.S. Pat. application Ser. No. 648,237 filed June 23, 1967, and entitled Photographic Elements and Methods.” Such layers appear to function as a light-diffusing layer.
• the silver halide in those layers can be removed in any suitable manner, such as with a silver halide solvent, e.g., sodium thiosulfate.
• a silver halide solvent e.g., sodium thiosulfate.
• nonimage-forming silver halide emulsion layers are free from any light'diffusing material, such as starch, which cannot be readily removed.
• These layers can in addition contain filter material, such as suitable dyes which absorb green and red radiation. This further reduces image spread when the elements are spectrally sensitized and are exposed to radiation longer than blue wavelength radiation.
• filter material such as suitable dyes which absorb green and red radiation. This further reduces image spread when the elements are spectrally sensitized and are exposed to radiation longer than blue wavelength radiation.
• an antihalation layer preferably on the same side of the support as the imagerecording emulsion layers. It is desirable to coat the antihalation layer on the same side of the support as the emulsion layers to obtain the desired reduction in image spread.
• suitable antihalation material can be employed.
• dyes can be used, preferably those which absorb the longest wavelengths of radiation to which the emulsion is sensitive.
• the dyes should be decolorizable during processing, e.g., in sulfite solution.
• a large number of dyes which can be used in antihalation layers are described in Jones et al. U.S. Pat. No. 3,282,699, issued Nov. 1, 1966.
• Also useful as antihalation layers are colloidal silver layers such as neutral (gray) colloidal silver dispersed in a suitable colloid such as gelatin. Bleachable dyes are especially useful.
• the emulsion can contain azaindenes as described in Knott U.S. Pat. No. 2,933,388, benzothiazolium compounds as described in Allen and Wilson U.S. Pat. No. 2,694,716 or a thioether as described In U.S. Pat. No. 3,046,132.
• the binder for the silver halide in the layers utilized herein can be any of the usual photographic binders. Gelatin is a highly useful and preferred binder. Other binders which can be employed herein with good results are described and referred to in Column 13 of Beavers U.S. Pat. No. 3,039,873 issued June 19, 1962. In addition to such binders, also useful are binders of the type disclosed in U.S. Pat. Nos. 3,142,568; 3,193,386; 3,062,674 and 3,220,844, including the water-insoluble polymers of alkyl acrylates and methacrylates, acrylic acid, sulfoalkyl acrylates or methacrylates and the like.
• a photographic element in accordance with this invention is prepared having the composition given below, concentration being in mg. per square foot:
• Layer 4 contains a fast silver bromoiodide (94:6) negative emulsion that is panchromatically sensitized and contains a cyan-dye-forming coupler of the type described in U.S. Pat. No. 2,474,293 as Compound No. 1.
• Layer 3 comprises a gelatin interlayer to prevent interlayer dye contamination resulting from oxidized developer wandering.
• Layer 2 contains a panchromatically sensitized silver bromoiodide (97:3) negative emulsion which is about 0.6 Log E slower in speed than the silver halide emulsion used in Layer 4 and also containing a cyan-dye-forming coupler as in Layer 4 plus a mercaptan releasing compound as described in U.S. Pat. No.
• Layer 1 comprises an unsensitized nonimage-forming silver bromoiodide (94:6) emulsion having grains less than about 1 micron in diameter, such as an emulsion of the type described in Millikan U.S. application Ser. No. 648,237, filed June 23, 1967.
• the element is exposed for one-fifth second in a sensitometer and processed by development for 15 minutes with primary aromatic amino color-developing agent.
• the color development process used is described in detail by Millikan in example 1 of Canadian Pat. No. 726,137 issued Jan. 18, 1966.
• the processed film has a 5 log E exposure latitude, and exhibits low-image spread.
• the film provides a low-contrast record of bright images and a high-contrast record of faint images It is well suited for directly recording and measuring the events which occur when a satellite in orbit reenters the earth's atmosphere and burns out.
• this example is repeated, except that the DlR coupler is not used, there IS an undesirable increase in the contrast of the bright image; the latitude of the faster emulsion layer is too low. and, the record produced by a bright image obliterates the record produced by a faint image in close geometrical proximity to the bright image.
• a photographic element comprising a support having coated thereon:
• a second photographic silver halide emulsion layer containing nondiffusible photographic coupler which forms image dye said second layer having a faster effective speed sensitivity than said first layer.
• each of said couplers has one of the following structural formulas:
• N CRo Formula II Ri-N 1i C-C ll 0 Y3 Rr Rrn Formulalll u- Ru wherein R,, X,, R,,, R R,',,, R R, and R each represents a group of the type employed in, respectively, open-chain ketomethylene couplers, 5-pyrazolonc couplers, and phenolic couplers; and Y,, Y, and Y each represents:
• each of said couplers has one of the following structural formulas:
• R and R each represents a member selected from the group consisting of alkyl, aryl, and a heterocyclic group containing at least one hetero atom selected from oxygen, sulfur and nitrogen;
• X represents a member selected from the group consisting of cyano and carbamyl;
• R represents a member selected from the group consisting of alkyl, carbamyl, amino, amido, benzamido, and alkamido;
• R, and R each represents a member selected from the group consisting of hydrogen, alkyl, aryl, a heterocyclic group containing at least one hetero atom selected from oxygen, sulfur and nitrogen, amino, carbonamido sulfonamido, sulfamyl.
• R, and R when taken together, represents the atoms required to complete a benzo group, and when taken separately, each represents a value selected from those given for R and R and, said Y and Y each represents:
• a a member selected from the group consisting of hydrogen, halogen, a thiocyano group, an acyloxy group, an aryloxy group, a cyclooxy group, and. when said R and R represent the atoms to tomplete a benzo group, Y represents any of the foregoing groups given for Y, and Y except aryloxy, and can in addition represent a cycloimido group, to complete said photographic image forming coupler", and,
• a photographic element as defined in claim 4 wherein said Y Y and Y; each represents a member selected from the group consisting of: a 2-nitrophenylthio group; a 2- aminophenylthio group; a S-tetrazolylthm group; a 2- benzothiazolylthio group; and, a S-phenyl l,3,4-ox adiazolylthio group, to complete said development inhibitor. releasing coupler.
• a photographic element comprising a support having coated thereon, in the order given:
• an unsensitized, nonimagerecording layer comprising gelatin having dispersed therein silver bromoiodide grains having an average diameter of about 0.l to 1 micron;
• a first panchromatically sensitized photographic gelatin silver bromoiodide emulsion layer containing the cyan image-forming coupler l-hydroxy-2-[8(2,4'-di-tcrtamylphenoxy)-N-butyl]-naphthamide and the development inhibitor-releasing coupler l-hydroxy-4-( I-phenyl- 5-tetrazolylthio)-2-[A-( ,4-dr-tert-amyl-phenoxy)-N-butyl]naphthamide; and,
• a second panehromatically sensitized photographic gelatin silver bromoiodide emulsion layer containing the cyan image forming coupler l-hydroxy-Z-l 8(2,4'-di-tertamylphenoxy)-N-butyl]-naphthamide, which layer produces an effective speed of about 0.6 Log E faster than said first silver halide emulsion layer.

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• 1968
  • 1968-05-20 US US730593A patent/US3620747A/en not_active Expired - Lifetime
• 1969
  • 1969-05-16 JP JP44037470A patent/JPS493843B1/ja active Pending
  • 1969-05-16 GB GB25122/69A patent/GB1275069A/en not_active Expired
  • 1969-05-19 DE DE19691925359 patent/DE1925359A1/de active Pending
  • 1969-05-20 FR FR6916208A patent/FR2008905A1/fr not_active Withdrawn
  • 1969-05-20 BE BE733342D patent/BE733342A/xx not_active IP Right Cessation

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