US3573920A - Fine grain silver halide emulsions containing novel dye combinations - Google Patents

Fine grain silver halide emulsions containing novel dye combinations Download PDF

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US3573920A
US3573920A US757789A US3573920DA US3573920A US 3573920 A US3573920 A US 3573920A US 757789 A US757789 A US 757789A US 3573920D A US3573920D A US 3573920DA US 3573920 A US3573920 A US 3573920A
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emulsion
dye
silver halide
fine grain
dyes
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Gary L Hiller
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Eastman Kodak Co
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Eastman Kodak Co
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    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09B—ORGANIC DYES OR CLOSELY-RELATED COMPOUNDS FOR PRODUCING DYES, e.g. PIGMENTS; MORDANTS; LAKES
    • C09B23/00—Methine or polymethine dyes, e.g. cyanine dyes
    • C09B23/02—Methine or polymethine dyes, e.g. cyanine dyes the polymethine chain containing an odd number of >CH- or >C[alkyl]- groups
    • C09B23/06—Methine or polymethine dyes, e.g. cyanine dyes the polymethine chain containing an odd number of >CH- or >C[alkyl]- groups three >CH- groups, e.g. carbocyanines
    • 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
    • G03C1/28—Sensitivity-increasing substances together with supersensitising substances
    • G03C1/29—Sensitivity-increasing substances together with supersensitising substances the supersensitising mixture being solely composed of dyes ; Combination of dyes, even if the supersensitising effect is not explicitly disclosed

Definitions

  • Fine grain photographic silver halide emulsions are spectrally sensitized with the combination of (1) a carbocyanine dye having a maximum sensitivity peak at a wavelength shorter than 6563 A., and (2) a carbocyanine dye having a maximum sensitivity peak at a wavelength longer than 6563 A.; each of the dyes comprising heterocyclic nuclei selected from a 3-sulfoalkylbenzothiazole nucleus, a 3-sulfoalkylbenzoselenazole nucleus and a 1- sulfoalkylnaphtho[1,2-d]thiazole nucleus, the two heterocyclic nuclei of each of said dyes being joined by a trimethine chain which contains an alkyl group on the meso carbon atom thereof.
  • This invention relates to novel combinations of cyanine dyes for extending the sensitivity of photographic silver halide emulsions to certain wavelength radiations in the red region of the spectrum, and more particularly to novel silver halide emulsions containing these novel dye combinations, and to photographic elements prepared therewith.
  • an object of this invention to provide novel cyanine dye combinations for extending the sensitivity of photographic silver halide emulsions to the red region of the spectrum with maximum sensitivity occurring at about 65 63 A.
  • Another object of this invention is to provide novel silver halide emulsions capable of accurate recording of fine detail at about 6563 A.
  • Another object of this invention is to provide photographic elements comprising a support material having at least one layer thereon containing a novel emulsion of the invention.
  • the increased inherent blue speed obtained with the dye combination is particularly unexpected because the dyes, When used individually or even in combinations have a substantial desensitizing effect on the inherent blue speed of conventional emulsions, i.e., emulsions having an average silver halide grain size greater than about 0.5 micron. Furthermore, the novel dye combinations of the invention give homogeneous and smooth flowing fine grain emulsions having excellent keeping stability, and cause little, if any, fogging in fresh or incubated emulsions. Accordingly, this invention provides photographic materials well suited for recording the radiations in the above specified region of 6563 A. in fine detail.
  • fine grain refers to silver halide emulsions wherein the silver halide grains have an average grain size of less than about 0.5 micron, and preferably about from 0.04 to 0.40 micron.
  • the novel dye combinations of the invention comprise (1) a carbocyanine dye having maximum sensitivity peak at a wavelength shorter than 6563 A., and preferably from about 635 to 655 nm., and (2) a carbocyanine dye having maximum sensitivity peak at a wavelength longer than 6563 A., and preferably from about 660 to 685 nm., said dyes 1) and (2) in each instance comprising first and second heterocyclic nuclei selected from the group consisting of a 3-sulfoalkylbenzothiazole nucleus, a 3- sulfoalkylbenzoselenazole nucleus, and a l-sulfoalkylnaphtho[1,2-d]thiazole nucleus, the two heterocyclic nuclei of each dye being joined together by a trimethine linkage having an alkyl group substituted at the mesocarbon atom thereof.
  • the proportions of the dyes employed in the dye combinations of the invention can vary over practically any limits and still give good results; however, the most efiicacious combinations are those containing the respective dyes in the proportions of about from 10 to 90% by weight of dye (1) and conversely about from 90 to 10% by weight of dye (2).
  • the total amount of these dyes is advantageously about from 0.10 to 1.0 gram per mole of silver.
  • the preferred carbocyanine dye compounds (1) of the invention have maximum sensitivity at a wavelength of about 635 to 655 nm., and include those dyes represented by the following formula:
  • R represents an alkyl group (preferably a lower alkyl containing from 1 to 4 carbon atoms), e.g., methyl, ethyl, propyl, isopropyl, butyl, etc.;
  • R and R each represents a sulfoalkyl group, e.g., B-sulfoethyl, 'y-sulfopropyl, 'y-sulfobutyl, w-sulfobutyl, etc.; and Z each represents the non-metallic atoms necessary to complete a benzothiazole nucleus, e.g., benzothiazole, 5-chlorobenzothiazole, S-bromobenzothiazole, S-methoxyhenzothiazole, 5 butoxybenzothiazole, 5 methylbenzothiazole, 5butylbenzothiazole, and the like nuclei.
  • the preferred carbocyanine dye compounds (2) of the invention have maximum sensitivity at a wavelength of from about 660 to 685 nm., and include those dyes represented by the following formula:
  • R R and R each represents a value given for R, R and R respectively; and, Z and Z each represents the non-metallic atoms necessary to complete a heterocyclic nucleus selected from (a) wherein each of Z and Z is a benzoselenazole nucleus, e.g., benzoselenazole, S-methoxybenzoselenazole, S-methylbenzoselenazole, etc., (b) wherein each of Z and Z is a naphtho- [1,2-d] thiazole nucleus, and (c) wherein Z is a naphtho- [1,2-d] thiazole nucleus and Z is a benzothiazole nucleus.
  • mono salts of the dyes defined by Formulas I and II above are included in these definitions, since such salts improve the solubility of the dyes without materially altering the sensitivity maximum peaks thereof.
  • useful mono salts of the dyes are alkali metals such as the monosodium, the monopotassium etc. salts, the mono salts of the dyes with trialkylamines such as the monotriethylamine, etc. salts, and the like.
  • Dye 0-1 and Dye C-II are representative of the prior art (outside this invention) and are included herein only for comparison purposes.
  • carbocyanine dyes defined by Formula II above are the following typical dye compounds.
  • Dye No. Compound VI Anhydro-Q-ethyl-fi-methoxy-3,3-di(3-sulfopropyl) selenacarbocyanine hydroxide, sodium salt VIII Anhydro-9-ethyl-3,3-di(3-su1fopropyl)-4,5-benzothiacarbocyanine hydroxide, sodium salt
  • the above Dyes III to VII and related dyes have, in general, been previously described in the prior art and are prepared, for example, by the general methods set forth in R. H. Sprague US. Pat. No. 2,503,776, issued Apr. 11, 1950; and A. E. Rosenoff U.S. Pat. No. 3,177,- 210, issued Apr. 6, 1965.
  • anhydro-2-(2-ethoXy-l-butenyl) 1 (3 sulfopropyl)naphtho[1,2-d]thiazolium hydroxide is prepared by refluxing for a period of 5 minutes a mixture of 64.2 g. (1 mol.) of anhydro-2- methyl-1(3-sulfopropyl)naphthol[1,2 d]thiazolium hydroxide and 70.4 g. (1 mol. +100% excess) of triethyl orthopropionate in 70 ml. of distilled cresol. On cooling the mixture the product crystallizes from solution. The light green solid is then collected, washed with acetone and dried. The crude yield of this compound 2o 23 4 2) is 64 g. (79%).
  • one or more of the carbocyanine dyes represented by Formula I above are incorporated with one or more of the carbocyanine dyes rep resented by Formula II above.
  • the invention is particularly directed to fine grain gelatino-silver-halide developing-out emulsions, including fine cubic grain silver halide emulsions.
  • the dye combinations can also be employed in silver halide emulsions in which the carrier or vehicle is a hydrophilic colloid other than gelatin, such as for example, albumin, agar-agar, gum arabic, alginic acid, etc., or a hydrophilic resin such as polyvinyl alcohol, polyvinyl pyrrolidone, a cellulose ether, a partially hydrolyzed cellulose acetate, acrylamide polymers, etc., which has no deleterious effect upon the light-sensitive silver halide.
  • the dyes of Formula I and Formula II can be employed in the combinations of the invention in various concentrations depending upon the particular emulsion, concentration of the silver halide, particular results desired, etc.
  • the optimum concentration of an individual sensitizing dye can be determined in a manner Well known to those skilled in the art by measuring the sensitivity of a series of test portions of the same emulsion, each portion containing a different concentration of the sensitizing dye.
  • the preferred combinations range about from to 90% to the carbocyanine dye of Formula I and conversely about from 90 to 10% of the carbocyanine dye of Formula II.
  • the optimum concentration of the dye combinations can, of course, be readily determined in the same manner, by measuring the sensitivity of a series of test portions of the same emulsion, each portion containing different concentrations of the individual dyes in the combination.
  • sensitizing dyes in silver halide emulsions are well known to those skilled in the art and these known techniques are employed in dispersing the dyes of the invention in the emulsions.
  • These dyes can be directly dispersed in the emulsions, or they can first be dissolved in some convenient solvent, such as pyridine, methyl alcohol, acetone, etc. (or mixtures of such solvents), or diluted with water in some instances, and added to the emulsions in the form of these solutions. If desired, the dyes can be separately dissolved in a given solvent and added separately to the emulsion, or they can be dissolved in the same or different solvent and these solutions mixed together before addition is made to the silver halide emulsions.
  • the dyes of the invention can be dispersed in the finished emulsions and should be uniformly distributed throughout the emulsions before the emulsions are coated on a suitable support, such as paper, glass, cellulose ester film, polyvinyl resin film (e.g., polystyrene film, polyvinyl chloride film, etc.), polyester film, etc.
  • a suitable support such as paper, glass, cellulose ester film, polyvinyl resin film (e.g., polystyrene film, polyvinyl chloride film, etc.), polyester film, etc.
  • Stock solutions of the dyes of Formulas I and II above are prepared by separately dissolving these dyes in appropriate solvents as described above. Then, to the flowable silver halide emulsion, the desired amount of stock solution of one of the dyes is slowly added while stirring the emulsion. Stirring is continued until the dye is thoroughly incorporated in the emulsion.
  • the desired amount of stock solution of the other dye is slowly added to the emulsion while stirring. Stirring is continued until the second dye is thoroughly incorporated in the emulsion.
  • the emulsions can then be coated on a suitable support and the coating allowed to dry. In some instances, it may be desirable to heat the sensitized emulsion for a few minutes before coating onto the suitable support.
  • the details of such coating techniques are well known to those skilled in the art. The foregoing procedure and proportions are to be regarded only as illustrative.
  • the invention is directed to any fine grain silver halide emulsion containing a combination of the aforesaid dyes whereby a supersensitizing effect is obtained, e.g., gelatino silver chloride, -chlorobromide, -chloroiodide, chlorobromoiodide, bromoiodide, etc., emulsions.
  • the fine grain emulsions employed in accordance with this invention can be prepared in any suitable manner, such as by the process described in the article entitled Properties of Photographic Emulsion Grains by Klein and Moisar, The Journal of Photographic Science, vol. 12, 1964, pages 242-245; or, by the method described by Illingsworth in French Patent 1,497,202 and corresponding U.S. patent application Ser. No. 500,366, filed Oct. 21, 1965, and now abandoned by maintaining, during emulsion precipitation, a pH of no more than 4.0 and the pAg within the range of 8.6 to 9.2.
  • Comparison Example 1 employs prior art coarse grain silver halide.
  • Example 1 This example illustrates the desensitizing effect of the individual dyes defined by Formulas I and II and certain combinations thereof on conventional type emulsions when incorporated therein.
  • the dyes are added to a silver bromoiodide emulsion containing 0.77 mole percent iodide of the type described by Trivelli and Smith, Phot. Journal, 79, 330 (1939), and having an aver-age grain size of 0.75 micron.
  • the individual dyes and dye combinations, dissolved in suitable solvents are added to separate portions of the emulsion at the concentrations indicated in Table 1 hereinafter. In each case, after being digested at about 50 C. for 10 minutes, the emulsion is coated at a coverage of 432 mg.
  • Example 2 This example illustrates that the combination of dyes of the invention defined by Formulas I and II above greatly increase the relative speed of fine grain emulsions, in the desired maximum sensitivity region of 6563 A., as compared with (a) the speed of the individual dyes in the same fine grain emulsion, and (b) as compared with the speed of the prior art combination of Dye C-I and Dye C-II in both the fine grain and in the large coarse grain emulsion, which latter is arbitrarily set at 100 for comparison purposes.
  • the procedure for the above testing is as follows.
  • a fine grain silver bromoiodide gelatin emulsion is prepared in essentially the same manner as described in Example 1 of Illingsworth US. patent application Ser. No. 500,366 filed Oct. 21, 1965, and is sulfur and gold sensitized.
  • the average grain size of the silver halide crystals in this fine grain emulsion is of the order of about 0.35 micron.
  • Also prepared is a coarse grain 0.75 micron emulsion duplicating that of above Example 1.
  • the dyes comprising comparison Dyes C-I and 0-H and Dyes III to VIII of the invention are incorporated individually, and in certain combinations thereof in separate portions of the above emulsions, specific concentrations, as indicated in Table 2 hereinafter.
  • a control of the fine grain emulsion containing no dye is also included in this table.
  • each of the samples is then coated at a coverage of 450 mg. silver per square foot on a cellulose acetate film support.
  • the cured coatings are then exposed and processed by the procedure described in above Example 1.
  • the sensitization ranges and the relative blue speed and the relative speed at 6563 A. are measured. The results are recorded in the following Table 2.
  • Fine grain photographic silver halide emulsions such as those listed above, containing the dye combinations of the invention can also contain such addenda as chemical sensitizers, e.g., sulfur sensitizers (e.g., allyl thiocarbamate, thiourea, allylisothiocyanate, cystine, etc.), various gold compounds (e.g., potassium chloroaurate, auric tri chloride, etc. (see Baldsiefen, U.S. Pat. No. 2,540,085, issued Feb. 6, 1951; Damschroder, U.S. Pat. No. 2,597,- 856, issued May 27, 1952 and Yutzy et a1.
  • additiveenda e.g., sulfur sensitizers (e.g., allyl thiocarbamate, thiourea, allylisothiocyanate, cystine, etc.), various gold compounds (e.g., potassium chloroaurate, auric tri chloride, etc. (see Bal
  • the color forming couplers can be incorporated into the photographic silver halide emulsions using any suitable technique, e.g., techniques of the type shown in Jelley et al. U.S. Pat. 2,322,027, issued June 15, 1943, Fierke et al. U.S. Pat. 2,801,171, issued July 30, 1957, Fisher U.S. Pats. 1,055,155 and 1,102,028, issued March 4, 1913 and June 30, 1914, respectively, and Wilmanns U.S. Pat. 2,186,849 issued Jan. 9, 1940. They can also be developed using incorporated developers such as polyhydroxybenzenes, aminophenols, 3-pyrazolidones, and the like.
  • a fine grain emulsion in accordance with claim 1 containing a color former 3.
  • R and R each represents an alkyl group containing from 1 to 4 carbon atoms; R R R and R each represents a sulfoalkyl group containing 1 to 4 carbon atoms; Z and Z each represents the non-metallic atoms necessary to complete a benzothiazole nucleus; and Z and Z each represents the non-metallic atoms necessary to complete a heterocyclic nucleus selected from the group consisting of: (a) wherein each of Z and Z is a benzoselenazole nucleus; (b) wherein Z and Z each represents a naphtho[l,2-d]thiazole nucleus; and, (c) wherein Z is a naphtho[1,2-d]thiazole nucleus and Z is a benzothiazole nucleus, the total weight of dye combination present in the emulsion being an amount effective to spectrally sensitize said emulsion.
  • a fine grain emulsion in accordance with claim 7 containing a color former 9.
  • a fine grain photographic silver halide emulsion wherein said silver halide grains have an average grain size within the range of 0.04 to less than 0.5 micron, containing a dye combination comprising (1) 10 to 90% by weight of the dye anhydro-S,5-dichloro-9-ethyl-3,3- di(4-sulfobutyl)-thiacarbocyanine hydroxide and (2) 90 to 10% by weight of the dye anhydro-9-ethyl-5-methoxy- 3,3 di(3 sulfopropyl) selenacarbocyanine hydroxide, sodium salt, the total weight of dye combination present in the emulsion being an amount effective to spectrally sensitize said emulsion.
  • a dye combination comprising (1) 10 to 90% by weight of the dye anhydro-S,5-dichloro-9-ethyl-3,3- di(4-sulfobutyl)-thiacarbocyanine hydroxide and (2) 90 to 10%
  • a fine grain emulsion in accordance with claim 12 wherein said silver halide has an average grain size of about from .04 to 0.4 micron.
  • a fine grain photographic silver halide emulsion wherein said silver halide grains have an average grain size within the range of 0.04 to less than 0.5 micron, containing a dye combination comprising (1) 10 to 90% by weight of the dye anhydro-5,5'-dichloro-9-ethyl-3,3'- di(4-sulfobutyl)-thiacarbocyanine hydroxide and (2) 90 to 10% by weight of the dye anhydro-9-ethyl-3,3'-di(3- sulfopropyl -4,5 ;4',5 '-dibenzothiacarbocyanine hydroxide salt, the total weight of dye combination present in the emulsion being an amount effective to spectrally sensitize said emulsion.
  • a fine grain photographic silver halide emulsion wherein said silver halide grains have an average grain size within the range of 0.04 to less than 0.5 micron, containing a dye combination comprising (1) 10 to 90% by weight of the dye anhydro-S,5-dichloro-9-ethyl-3,3- di(3-sulfobutyl)-thiacarbocyanine hydroxide and (2) 90 to 10% by weight of the dye anhydro-9-ethyl-5-metlioxy- 3,3-di(3-sulfopropyl)-selenacarbocyanine hydroxide salt, the total Weight of dye combination present in the emul- 12 sion being an amount effective to spectrally sensitize said emulsion.
  • a dye combination comprising (1) 10 to 90% by Weight of the dye anhydro-S,5-dichloro-9-ethyl-3,3'-di(3- sulfobutyl)thiacarbocyanine hydro
  • a photographic element comprising a support coated with at least one layer of a fine grain photographic silver halide emulsion of claim 1.
  • a photographic element comprising a support coated with at least one layer of a fine grain photographic silver halide emulsion of claim 7.
  • a photographic element comprising a support coated with at least one layer of a fine grain silver halide emulsion of claim 12.
  • a photographic element comprising a support coated with at least one layer of a fine grain photographic silver halide emulsion of claim 15.
  • a photographic element comprising a support coated with at least one layer of a fine grain photographic silver halide emulsion of claim 18.
  • a photographic element comprising a support coatedwith at least one layer of a fine grain photographic silver halide emulsion of claim 21.
  • a photographic element comprising a support coated with at least one layer of a fine grain silver halide emulsion of claim 27.
  • R and R each represents an alkyl group; R R R and R each represents a sulfoalkyl group; Z and Z each represents the non-metallic atoms necessary to complete a benzothiazole nucleus; and, Z and Z each represents the non-metallic atoms necessary to complete a heterocyclic nucleus selected from the group consisting of: (a) wherein each of Z and Z is a benzoselenazole nucleus; (b) wherein Z and Z each represents a naphtho [l,2-d]thiazole nucleus; and, (c) wherein Z is a naphtho[1,2-d]thiazo1e nucleus and Z is a benzothiazole nucleus, the total weight of dye combination present in the emulsion being an amount effective to spectrally sensitize said emulsion.
  • a fine grain emulsion in accordance with claim 38 containing a color former is a fine grain emulsion in accordance with claim 38 containing a color former.

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BE (1) BE724740A (enrdf_load_stackoverflow)
CA (1) CA917985A (enrdf_load_stackoverflow)
DE (1) DE1811542A1 (enrdf_load_stackoverflow)
FR (1) FR1593828A (enrdf_load_stackoverflow)
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2224367A1 (de) * 1971-05-18 1972-11-23 Fuji Photo Film Co. Ltd., Ashigara-Kamigun, Kanagawa (Japan) Lichtempfindliches Material mit nur geringer Änderung des darin gebildeten latenten Bildes
US3753721A (en) * 1970-08-13 1973-08-21 Eastman Kodak Co Photographic materials
JPS4911121A (enrdf_load_stackoverflow) * 1972-05-29 1974-01-31
US3808008A (en) * 1970-09-10 1974-04-30 Fuji Photo Film Co Ltd Spectrally sensitized silver halide photographic emulsion
US3819383A (en) * 1971-07-12 1974-06-25 Ilford Ltd Super-sensitising combination in photographic silver halide emulsion

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS515781B1 (enrdf_load_stackoverflow) * 1971-03-12 1976-02-23
JPS5225333B1 (enrdf_load_stackoverflow) * 1974-04-19 1977-07-07
JPS5225331B1 (enrdf_load_stackoverflow) * 1974-04-19 1977-07-07
JPS5225334B1 (enrdf_load_stackoverflow) * 1974-04-19 1977-07-07

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3753721A (en) * 1970-08-13 1973-08-21 Eastman Kodak Co Photographic materials
US3808008A (en) * 1970-09-10 1974-04-30 Fuji Photo Film Co Ltd Spectrally sensitized silver halide photographic emulsion
DE2224367A1 (de) * 1971-05-18 1972-11-23 Fuji Photo Film Co. Ltd., Ashigara-Kamigun, Kanagawa (Japan) Lichtempfindliches Material mit nur geringer Änderung des darin gebildeten latenten Bildes
JPS519609B1 (enrdf_load_stackoverflow) * 1971-05-18 1976-03-29
US3819383A (en) * 1971-07-12 1974-06-25 Ilford Ltd Super-sensitising combination in photographic silver halide emulsion
JPS4911121A (enrdf_load_stackoverflow) * 1972-05-29 1974-01-31

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GB1250658A (enrdf_load_stackoverflow) 1971-10-20
DE1811542A1 (de) 1969-07-24
CA917985A (en) 1973-01-02
FR1593828A (enrdf_load_stackoverflow) 1970-06-01

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