Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
  • G03C1/00—Photosensitive materials
  • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
  • G03C1/04—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with macromolecular additives; with layer-forming substances
  • G03C1/043—Polyalkylene oxides; Polyalkylene sulfides; Polyalkylene selenides; Polyalkylene tellurides
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C323/00—Thiols, sulfides, hydropolysulfides or polysulfides substituted by halogen, oxygen or nitrogen atoms, or by sulfur atoms not being part of thio groups

Definitions

• This invention relates to photographic silver halide emulsions, and more particularly, to an improved means for sensitizing such photographic silver halide emulsions.
• the compounds used in our invention do not appear to be chemical sensitizers in the usual sense, since they increase speed by their presence during exposure and processing and require no digestion with the photographic emulsion to produce an increase in speed, nor does their chemistry indicate that they are likely to react with silver halide under normal emulsion conditions.
• novel sensitizers of our invention are quite unique in that the effects produced are additive in photographic emulsions which have already been sensitized to their optimum, or near-optimum, with conventional chemical sensitizers, such as labile sulfur compounds.
• the novel sensitizers of our invention can be used to sensitize photographic silver halide emulsions containing no other sensitizers, if desired.
• the novel sensitizers of our invention are not strictly chemical sensitizers, since chemical sensitizers do not generally provide the additive effects of the type mentioned.
• an object of our invention to provide photographic silver halide emulsions which have been sensitized with various non-polymeric compounds com ice taining a plurality of sulfur atoms.
• Another object of our invention is to increase the sensitivity of ordinary photographic silver halide emulsions which have been sensitized with chemical sensitizers, such as compounds containing labile sulfur atoms, or gold-containing compounds.
• chemical sensitizers such as compounds containing labile sulfur atoms, or gold-containing compounds.
• non-polymeric open-chain compounds which can be characterized as polyoxathio others.
• These non-polymeric compounds contain their sulfur atoms in the form of thioether linkages.
• thioether linkages we mean a linkage wherein the sulfur atom is divalent and is joined to two non-oxocarbonylic carbon atoms.
• Compounds useful in sensitizing photographic silver halide emulsions according to the present invention are to be distinguished from the polymeric thioether compounds described in US. patent application Serial No. 779,874, filed December 12, 1958, by J. R. Dann and I. J. Chechak.
• the polymeric compounds described in this latter application are generally characterized as having high molecular weights and as containing characteristic repeating units or groups.
• sensitizing compounds useful in practicing our invention are non-polymeric and can be represented by the following general formula:
• X represents a divalent linkage selected from oxygen, sulfur, and the group:
• X and X each represents an oxygen atom or a sulfur atom, provided at least one of the groups se lected from X, X and X is an oxygen atom and at least one of the groups selected from X, X and X is a sulfur atom, X represents a methylene carboxy radical, i.e.,
• It CH2CO R represents a hydroxyl group, an alkoxyl group (e.g., methoxyl, et-hoxyl, propoxyl, butoxyl, etc.), a car-bamyl group, i.e.,
• R represents an ethylene radical, such as ethylene or ethylene substituted by an alkyl group, such as methyl
• d represents a positive integer of from 1 to 2
• n represents a positive integer of from 1 to 3.
• the compounds of Formula I above can be prepared according to methods which have been previously described in the technical literature. For example, these compounds can be prepared by condensing together a monothiol with a dihalogenated ether compound in the presence of sufficient alkali to form the alkali metal salt of the monothiol. Alternatively, these compounds can be prepared by condensing together an organic halide with sodium sulfide. These two alternative methods of .syntheses can be outlined as follows:
• the reaction mixture was heated under a reflux condenser on the steam bath for 20 hours, the solvent removed under vacuum, and the product separated from the sodium chloride formed, by extraction with hot absolute ethanol 3 and ethyl acetate. The solvents were removed from the combined extracts and the product was distilled. B.P. 220230 C./3 mm.
• NHzGOCHCHQSCHQCHZOCHzCHzOCHeCHzSGHzCIICONHs The sensitize of our invention can be added to the Seventeen grams of methacrylamide (0.2 mole), 1 emulsion before the final digestion or after-ripening, or g. of bis(2-mercaptoetl1oxy)ethane (0.1 mole), and they can be added immediately prior to the coating.
• sensitizers of our invention can be added to photo- 19.7 g.
• a prodgraphic emulsions using any of the well known techniques uct was obtained which boiled over the range of 166-188 in emulsion making.
• the sensitizers can be C. at 2 mm.
• Decomposition began when further distildissolved in a suitable solvent and added to the silver lation was attempted.
• the product somewhat dark in halide emulsion, or they can be added to the emulsion in the formof a dispersion similar to the technique used to incorporate certain types of color-forming compounds (couplers) in a photographic emulsion. Techniques of this type are described in Jelley et al. U.S.
• the solvent should be selected so that it has no harmful efiect upon the emulsion, and generally solvents or diluents which are miscible with water are to be preferred.
• Water or dilute alkali is a dispersing medium for some of the sensitizers of the invention.
• the sensitizers can be dissolved in a solvent, such as etha nol, acetone, pyridine, N,N-dimethylformamide, etc., and added to the emulsion in this form.
• certain of the sensitizers can be prepared in finely-divided form and dispersed in water alone, or in the presence of a suitable dispersing agent (such as alkali metal salts of aromatic or aliphatic sulfonic acids) and added to the emulsion in this form.
• a suitable dispersing agent such as alkali metal salts of aromatic or aliphatic sulfonic acids
• the sensitizers of our invention should have suificient water-dispersibility so that they can be adsorbed to or associated with the grains of the silver halide present in the emulsion in sufiicient amount to sensitize the emulsion. It is apparent that the optimum amount for each of the sensitizers will vary somewhat from emulsion to emulsion and from compound to compound.
• the optimum amount of any given sensitizer can be determined for any particular emulsion by running a series of tests in which the quantity of sensitizer is varied over a given range. Exposure of the treated emulsion in conventional photographic testing apparatus, such as an intensity scale sensitometer, will reveal the most advantageous concentrations for that sensitizer in that particular emulsion. Such matters are well understood by those skilled in the art.
• photographic emulsions used in practicing our invention are of the developing-out type.
• the emulsions can be chemically sensitized by any of the accepted procedures.
• the emulsions can be digested with naturally active gelatin, or sulfur compounds can be added such as those described in Sheppard US. Patent 1,574,944, issued March 2, 1926, Sheppard et a1.
• the emulsions can also be treated with salts of the noble metals such as ruthenium, rhodium, palladium, iridium, and platinum.
• the noble metals such as ruthenium, rhodium, palladium, iridium, and platinum.
• Representative compounds are ammonium chloropalladate, potassium ohloroplatinate,
• the emulsions can also be chemically sensitized with gold salts as described in Waller et al. U.S. Patent 2,399,- 083, issued April 23, 1946, or stabilized with gold salts as described in Damschroder U.S. Patent 2,597,856, issued May 27, 1952, and Yutzy and Leermakers U.S. Patent 2,597,915, issued May 27, 1952.
• Suitable compounds are potassium ohloroaurite, potassium 'aurithiocyanate, potassium chloroaurate, auric trichloride and Z-aurosulfobenzothiazole methochloride.
• the emulsions can also be chemically sensitized with reducing agents such as stannous salts (Carroll U.S. Patent 2,487,850, issued November 15, 1949), polyamines, such as diethyl triamine (Lowe and Jones U.S. Patent 2,518,698, issued August 15, 1950), polyamines, such as spermine (Lowe and Allen U.S. Patent 2,521,925, issued September 12, 1950), or bis(fl-aminoethyl) sulfide and its water-soluble salts (Lowe and Jones U.S. Patent 2,521,926, issued September 12, 1950).
• reducing agents such as stannous salts (Carroll U.S. Patent 2,487,850, issued November 15, 1949), polyamines, such as diethyl triamine (Lowe and Jones U.S. Patent 2,518,698, issued August 15, 1950), polyamines, such as spermine (Lowe and Allen U.S. Patent 2,521,925, issued September 12, 1950), or bis(fl-
• the emulsions can also be optically sensitized with cyanine and merocyanine dyes, such as those described in Brooker U.S. Patents 1,846,301, issued February 23,
• the emulsions can also be stabilized with the mercury compounds of Allen, Byers and Murray U.S. Patent 2,728,663, issued December 27, 1955 Carroll and Murray U.S. Patent 2,728,664, issued December 27, 1955; and Leubner and Murray U.S. Patent 2,728,665, issued December 27, 1955; the triazoles of Heimbach and Kelly U.S. Patent 2,444,608, issued July 6, 1948; the azaindenes of Heimbach and Kelly U.S. Patents 2,444,605 and 2,444,606, issued July 6, 1948; Heimbach U.S. Patents 2,444,607, issued July 6, 1948, and 2,450,397, issued September 28, 1948; Heimbach and Clark U.S. Patent 2,444,609, issued July 6, 1948; Allen and Reynolds U.S.
• the emulsions may also contain speed increasing compounds of the quaternary ammonium type of Carroll U.S. Patent 2,271,623, issued February 3, 1942; Carroll and Allen U.S. Patent 2,288,226, issued June 30, 1942; and Carroll and Spence U.S. Patent 2,334,864, issued November 23, 1943; and the polyethylene glycol type of Carroll and Beach U.S. Patent 2,708,162, issued May 10, 1955 or the thiopolymers of Graham and Sagal U.S. application Serial No. 779,839, filed December 12, 1958, or Dann and Chechak U.S. application Serial No. 779,874, filed December 12, 1958, or the quaternary ammonium salts and polyethylene glycols of Piper U.S. Patent 2,886,437, issued May 12, 1957.
• the emulsions may contain a suitable gelatin plasticizer such as glycerine; a dihydroxy alkane such as 1,5-pentane diol as described in Milton and Murray U.S. application Serial No. 588,951, filed June 4, 1956; an ester of an ethylene bis-glycoiic acid such as ethylene bis(methyl glycolate) as described in Milton U.S. application Serial No. 662,564, filed May 31, 1957; bis-(ethoxy diethylene glycol) succinate as described in Gray U.S. application Serial No.
• the emulsions may be hardened with any suitable hardener for gelatin such as formaldehyde; a halogensubstituted aliphatic acid such as mucobromic acid as described in White U.S. Patent 2,080,019, issued May 11, 1937; a compound having a plurality of acid anhydride groups such as 7,8-diphenylbicyclo (2,2,2)-7-octene-2,3, 5,6-tetra-carboxylic dianhydride, or a dicarboxylic or a disulfonic acid chloride such as terephthaloyl chloride or naphthalene-1,S-disulfonyl ChlOl'ide as described in Allen and Carroll U.S.
• any suitable hardener for gelatin such as formaldehyde
• a halogensubstituted aliphatic acid such as mucobromic acid as described in White U.S. Patent 2,080,019, issued May 11, 1937
• Patent 2,732,316 issued January 24, 1956; a dialdehyde or a sodium bisulfite derivative thereof, the aldehyde groups of which are separated by 2-3 carbon atoms, such as B-methyl glutaraldehyde bissodium bisulfite as described in Allen and Burness U.S. patent application Serial No. 556,031, filed December 29, 1955; a bis-aziridine carboxamide such as trimethylene bis(1-aziridine carboxamide) as described in Allen and Webster U.S. patent application Serial No. 599,891, filed July 25, 1956; or 2,3-dihydroxy dioxane as described in Jefifreys U.S. Patent 2,870,013, issued January 20, 1957.
• the emulsions may contain a coating aid such as saponin; a lauryl or oleyl monoether of polyethylene glycol as described in Knox and Davis U.S. Patent 2,831,- 766, issued April 22, 1958; a salt of a sulfated and alkylated polyethylene glycol ether as described in Knox and Davis US. Patent 2,719,087, issued September 27, 1955 an acylated alkyl taurine such as the sodium salt of N- oleoyl-N-rnethyl taurine as described in Knox, Twardokus and Davis U.S.
• a coating aid such as saponin
• a lauryl or oleyl monoether of polyethylene glycol as described in Knox and Davis U.S. Patent 2,831,- 766, issued April 22, 1958
• a salt of a sulfated and alkylated polyethylene glycol ether as described in Knox and Davis US. Patent 2,719,087, issued September 27, 1955
• Patent 2,739,891 issued March 27, 1956; the reaction product of a dianhydride of tetracarboxybutane with an alcohol or an aliphatic amine containing from 8 to 18 carbon atoms which is treated with a base, for example, the sodium salt of the monoester of tetracarboxybutane as described in Knox, Stenberg and Wilson U.S. Patent 2,843,487, issued July 15, 1958; a watersoluble maleopimarate or a mixture of a water-soluble maleopimarate and a substituted glutamate salt as described in Knox and Fowler U.S.
• Patent 2,823,123 issued February 11, 1958; an alkali metal salt of a substituted amino acid such as disodium N-(carbo-p-tert. octylphenoxypentaethoxy)-glutamate as described in Knox and Wilson U.S. patent application Serial No. 600,679, filed July 30, 1956; or a sulfosuccinamate such as tetrasodium N-(1,2-dicarboxyethyl)-N-octadecyl sulfosuccmamate or N-lauryl disodium sulfosuccinamate as described in Knox and Stenberg U.S. patent application Serial No. 691,125, filed October 21, 1957.
• the addenda which we have described may be used in various kinds of photographic emulsions. In addition to being useful in X-ray and other nonoptically sensitized emulsions they may also be used in orthochromatic, panchromatic, and infrared sensitive emulsions. They may be added to the emulsion before or after any sensitizing dyes which are used.
• Various silver salts may be used as the sensitive salt such as silver bromide, silver iodide, silver chloride, or mixed silver halides such as silver chlorobromide or silver bromoiodide.
• the agents may be used in emulsions intended for color photography, for example, emulsions containing color-forming couplers or emulsions to be developed by solutions containing couplers or other color-generating materials, emulsions of the mixed-packet type, such as described in Godowsky U.S. Patent 2,698,794, issued January 4, 1955; or emulsions of the mixed-grain type, such as described in Carroll and Hanson U.S. Patent 2,592,243, issued April 8, 1952.
• These agents can also be used in emulsions which form latent images predominantly on the surface of the silver halide crystal or in emulsions which form latent images predominantly inside the silver halide crystal, such as 10 those described in Davey and Knott U.S. Patent 2,592,- 250, issued April 8, 1952.
• the dispersing agent for the silver halide in its preparation gelatin or some other colloidal material such as colloidal albumin, a cellulose derivative, or a synthetic resin, for instance, a polyvinyl compound.
• colloidal albumin colloidal albumin
• a cellulose derivative a cellulose derivative
• synthetic resin for instance, a polyvinyl compound.
• colloids which may be used are polyvinyl alcohol or a hydrolyzed polyvinyl acetate as described in Lowe U.S. Patent 2,286,215, issued June 16, 1942; a far hydrolyzed cellulose ester such as cellulose acetate hydrolyzed to an acetyl content of 1926% as described in U.S.
• Patent 2,768,154 issued October 23, 1956; or containing cyano-acetyl groups such as the vinyl alcohol-vinyl cyanoacetate copolyrner as described in Unruh, Smith and Priest U.S. Patent 2,808,331, issued October 1, 1957; or a polymeric material which Y results from polymerizing a protein or a saturated acylated protein with a monomer having a vinyl group as described in U.S. Patent 2,852,382, of Illingsworth, Dann and Gates, issued September 16, 1958.
• cyano-acetyl groups such as the vinyl alcohol-vinyl cyanoacetate copolyrner as described in Unruh, Smith and Priest U.S. Patent 2,808,331, issued October 1, 1957; or a polymeric material which Y results from polymerizing a protein or a saturated acylated protein with a monomer having a vinyl group as described in U.S. Patent 2,852,382, of Illingsworth, Dann and Gates, issued September 16, 1958.
• compatible mixtures of two or more of these colloids may be employed for dispersing the silver halide in its preparation.
• Combinations of these antifoggants, sensit-izers, hardeners, etc, v may be used.
• the sensitizing compounds of our invention can be used both in emulsions intended for black-and-white photogr raphy, or emulsions intended for color photography.
• the color-forming compounds can be of the customary types employed in 1 3 l-p-laurylphenyl-3-methyl-5-pyrazolone 1-fi-naphthyl-3amyl-5-pyrazolone l-p-nitrophenyl-3-n-amyl-5-pyrazolone l-p-pl1enoxyphenyl-3-n-amyl-5-pyrazolone 1-pheny-l-3-n-amyl-5-pyrazolone 1,4-phenylene bis-3-( l-phenyl-S-pyrazolone) l-phenyl-3-acetylamino-5-pyrazolone l-phenyl-3-propionylamino-S-pyrazolone 1phenyl-3-n-valerylamino-5-pyrazolone l-phenyl-3-chloroacetylamino-5-pyrazolone 1-phenyl-B-dichloroacetylamino-S-pyrazolone
• sensi-tizers included within our invention as Well as the large number of color-forming compounds which can be employed in combination therewith, a number of combinations of sensitizing compounds and color-forming compounds is possible.
• screening technique described by Pontius and Thompson in Photo. Sci. Eng, vol. 1, pages 4-51, can be used to get an idea of the potential effectiveness of a given combination for use in a photographic color element containing a coupler.
• sensitizers can be added to ordinary photographic silver halide emulsions of the type used in black-andwhite photography, such as gelatino-silver-bromiodide emulsions, and the emulsions exposed in an intensity scale sensitometer to daylight quality radiation for a fraction of a second (usually & and processed for about 15 minutes in a phenylenediamine color developer, to which has been added 10 g. per liter of H-acid.
• the pH of this developer is usually adjusted to 10.8 by adding sodium hydroxide.
• a suitable developer composition for this screening technique is as follows:
• Benzyl alcohol cc 10 Sodium hexamethaphosphate g 2.0 Sodium sulfite g 2.0 Sodium hydroxide g 3.4 H-acid (lamino-8-naphthol-3,6 disulfonic acid) 4-amino-3-rnethyl-N-ethyl-N-(,B methyl sulfonamidoethyl)aniline sulfate g 8.0 Sodium carbonate monohydrate g 40.0 Sodium bromide g 1.5 Sodium thiocyanate g 0.2 Benzotriazole g .03
• the following data show the effect produced by adding a sensitizing compound of our invention to an ordinary negative speed silver bromiodide emulsion which has been digested to optimum sensitivity with a mixture of a labile sulfur compound of the type shown in US. Patent 1,623,499 and a gold compound of the type shown in US. Patent 2,448,060.
• the emulsion had been red-sensitized to that region of the spectrum lying between about 600 and 700 mg and it contained a coupler dispersion of one of the color-forming compounds for producing the cyan image upon color development, such as a dispersion of a phenol coupler, e.g., any one of couplers Nos. 1 to 6 of Fierke U.S.
• Patent 2,801,171 (column 2) in a suitable solvent, such as tri-o-cresylphosphate or dibutylphthalate.
• a suitable solvent such as tri-o-cresylphosphate or dibutylphthalate.
• polythiallkylenediol sensitizers as identified in the table.
• the emulsions were then coated on conventional film support and dried.
• the coatings were exposed in an Eastman type lb sensitometer for X Sec. to the light emitted by a 500-watt tungsten lamp adjusted to 6l00 K. and further modulated by a Wratten No. 15 filter.
• the exposed coatings were then processed through a reversal process, such as the following:
• the exposed film was developed in a developer having the following compositions:
• the element was again washed and treated once again with the clearing and fixing bath identified above.
• the element was again washed and treated in a stabilizing bath havingthe following composition:
• Formaldehyde (37% by weight) cc 7.0 Dispersing agent 1 g 0.5 Water to make 1 liter.
• Triton X i.e., an alkylaryl polyether alcohol (oetylphenoxypolyethoxy ethanol).
• sensitizers do 9 06 126 While the effect of our sensitizers has been illustrated in Table 11 above with respect to a photographic element having only one color-sensitized layer, it is to be understood that the advantages are also obtained in multilayer tfilms containing a plurality of photographic emulsion layers which have their sensitivity in different regions of the spectrum.
• the sensitizers are effective not only in redsensitized emulsions but in emulsions which have their maximum sensitivity in the blue region of the spectrum, or in emulsions which have their maximum sensitivity in the green region of the spectrum.
• photographic silver halide emulsions can be sensitized by compounds similar to those of Formula 1 above, except that one or more of the ethylene groups is replaced by methylene, propylene, etc.
• R represents a member selected from the class consisting of a hydroxyl group, an alkoxyl group, and a carbamyl group
• R represents an ethylene radical
• X represents a divalent radical selected from the class consisting of an oxygen atom, a sulfur atom
• the group X CH CH X X and X each represents a divalent radical selected from the class consisting of an oxygen atom and a sulfur atom, provided one of the radicals selected from the class consisting of X, X and X is an oxygen atom and provided one of the radicals selected 18 from the class consisting of X, X and X is a sulfur atom
• X represents the divalent radical -CH2(]% O d represents a positive whole number of from 1 to 2 and n represents a positive whole number of from 1 to 3.
• R represents a member selected from the class consisting of a hydroxyl group, an alkoxyl group and a carbamyl group
• X represents a divalent radical selected from the class consisting of an oxygen atom, a sulfur atom
• the radical -X CH CH X X and X each represents a divalent radical selected from the class consisting of an oxygen atom and a sulfur atom, provided one of the radicals selected from the class consisting of X, X and X represents an oxygen atom and provided one of the radicals selected from the class consisting of X, X and X represents a sulfur atom
• n represents a positive whole number of from 1 to 3.
• R represents a member selected from the class consisting of a hydroxyl group, an alkoxyl group, and a carbamyl group
• R represents an ethylene radical
• X represents a divalent radical selected from the class consisting of an oxygen atom, a sulfur atom and the radical X CH CH X X and X each represents a divalent radical selected fiom the class consisting of an oxygen atom and a sulfur atom, provided one of the radicals selected from the class consisting of X, X and X represents an oxygen atom and one of the radicals selected from the class consisting of X, X, and X represents a sulfur atom, and n represents a positive whole number of from 1 to 3.
• a photographic silver halide emulsion containing V 19 a sensitizing amount of the compound represented by the following formula:
• R represents a member selected from the class consisting of a hydroxyl group, an alkoxyl group, and a carbamyl group
• R represents an ethylene radical
• X represents a divalent radical selected from the class consisting of an oxygen atom, a sulfur atom
• the group --X CH CH X X and X each represents a divalent radical selected from the class consisting of an oxygen atom and a sulfur atom, provided one of the radicals selected from the class consisting of X, X and X is an oxygen atom and provided one of the radicals selected from the class consisting of X, X and X is a sulfur atom
• X represents the divalent radical d represents a positive Whole number of from 1 to 2 and n represents a positive whole number of from 1 to 3.
• R represents a member selected from the class consisting of a hydroxyl group, an alkoxyl group, and a carbamyl group
• R represents an ethylene radical
• X represents a divalent radical selected from the class consisting of an oxygen atom, a sulfur atom and the radical --X CH CH X X and X each represents a divalent radical selected from the class consisting of an oxygen atom and a sulfur atom, provided one of the radicals selected from the class consisting of X, X and X represents an oxygen atom and one of the radicals selected from the class consisting of X, X and X represents a sulfur atom, and n represents a positive whole number of from 1 to 3.
• a photographic silver halide emulsion containing a color-forming compound capable of coupling with the oxidation products of a color developer containing at least one primary aminoaryl group to produce a colored compound said emulsion containing a sensitizing amount of a compound selected from those represented by the following general formula:
• R represents a member selected from the class consisting of a hydroxyl group, an alkoxyl group and a carbamyl group
• X represents a divalent radical selected from the class consisting of an oxygen atom, a sulfur atom
• the radical -X CH CH X X and X each represents a divalent radical selected from the class consisting of an oxygen atom and a sulfur atom, provided one of the radicals selected from the class consisting of X, X and X represents an oxygen atom and provided one of the radicals selected from the class consisting of X, X and X represents a sulfur atom
• n represents a positive whole number of from 1 to 3.

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  • BE BE595891D patent/BE595891A/xx unknown
• 1959
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