US2945763A - Green sensitization of photographic silver halide emulsions - Google Patents

Green sensitization of photographic silver halide emulsions Download PDF

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US2945763A
US2945763A US743069A US74306958A US2945763A US 2945763 A US2945763 A US 2945763A US 743069 A US743069 A US 743069A US 74306958 A US74306958 A US 74306958A US 2945763 A US2945763 A US 2945763A
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dye
dyes
formula
emulsions
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Jean E Jones
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Eastman Kodak Co
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Eastman Kodak Co
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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
    • 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
    • G03C1/10—Organic substances
    • G03C1/12—Methine and polymethine dyes
    • G03C1/14—Methine and polymethine dyes with an odd number of CH groups
    • G03C1/18—Methine and polymethine dyes with an odd number of CH groups with three CH groups
    • 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

Definitions

  • This invention relates to photography, and more particularly, to a method for altering the sensitivityV of greensensitized photographic silver halide emulsions. ⁇
  • benzimidazolocarbocyanine dyes are useful in sensitizing photographic silver halide Y emulsions to the green region of the spectrum, i.e., ⁇ that portion of the-spectrum lying between aboutV 50Oand, 60'() ma. These dyes have been of particular interestras greensensitizers, andl in particular, in the emulsions intended for use in color photography,V since they aregenera-lly characterized by very sharp absorption. Dyes of this type have been previously described inthe technical and patent literature. See, for example, Ogata Proceedings of the Imperial Academy (Tokyo), v ol. 9 (1933), page- 602,. Among the most useful of the benzimidazolocarbocyanine dyes are those containing one or more chlorine atoms substituted on the benzene ring of the benzimidazole nucleus. Y
  • an ⁇ object of my invention to. provide an improved means of sensitizing photographic silver halide emulsions to the green region of the spectrum. Another object is to produce vein silver halide', emulsions having improved green, sensitivity.k Still, an: other object is to provide photographic silver-halide emulsions which have been supersensitized bya combination of! the above-mentioned sensitizing dyes' with4 certain heterocyclic compoundsv as hereinafter defined.
  • sensitizing dyes include those representedlby the followingV general formula:
  • R andv R1k each represents and alkyl group; suchV asmethyl, ethyl, Ilit-hydroxyethyl, n-propyl', nbutyl', ,tt-r'zar box-yethyl, y-carboxypropyl, (or 4,).l-carboxylhutyl", )9s-sulfoethyl, y-sullfoinopyL ⁇ ⁇ i-sulfelmtyl.,v fsulfebutyl, etc.
  • Patent O ⁇ ice 2 Y (e, .g., an alkyl group ⁇ ycontaining from 1 to 4; carbon atoms), R2 and R3 each represents an alkyl group, such as methyl, ethyl, n-propyl, n-butyl, etcte-a, ⁇ an alkyl Kunststoff containing from 1 to 4 carbon atoms.) Aor, an aryl group, such as phenyl, o, mor p-tolyl, etc.
  • d and 1 1 each.rep-4 resents a positive integer of from l to- 3 and X, represents an acid radical, such as chloride, bromide, iodide, benzenesulfonate, p-toluenesulfonate, methylsulfate ethylsulfate,
  • R or R1 of Formula I represents acid-substituted alkyl groups, such as a sulfoalkyl group
  • the dyes are generally regarded as anhydro dyes, and, a particularly useful group of such dyes can be represented by the following general formula:
  • R has the values given above, and ⁇ D represents an alkylenel group, such as'ethyl'ene, trimethylene, tetra- Y methylene, ymethyltrimethylene, etc.
  • Another.' group of dyes embraced by Formula I which are particularly useful in my invention can be representedby the following general formula:
  • R5r represents an alkyl group, such as methyl, ethyl, etc. (e.g., an alkyl group containing from l to 2 carbon atoms), or an aryl group, such as phenyl, o, mor p-tolyl (e.gl, a' mononuclear aromatic, group, of the benzene series), Q; represents an oxygen atom or an arylimino group, such as phenylimino, tolylimino, chlorophenylimino, etc.
  • Z represents the non-metallic atoms necessary to complete a heterocyclic nucleus of the naphthothiazoline series or the naphthoselenazoline series.
  • the carbocyclicY rings ofthe nuclei defined by Z above can contain inert substituents, such as alkyl groups (e.g., methyl, ethyl, etc.), alkoXy groups (e.g., methoXyl, ethoxyl, etc.), etc.
  • the compounds of Formula II, wherein Q represents Il C-:CH-C-CHS an oxygen atom can be prepared according to the method described in Brooker et al. U.S. Patent 2,112,139, issued March 22, 1938.
  • the compounds of Formula II, wherein Q represents an arylimino group can be prepared as described in Brooker et al. U.S. Patent 2,298,732, issued October 13, 1942.
  • the degree of hypsochromic shift in the absorption ofthe benzimidazolocarbocyanine dyes can be controlled to some extent by the amount of the compound of Formula II which is added.
  • addition of increased quantities of the compoundrof Formula II will produce an increased shift in absorption up to a point which varies from dye to dye and addition vof further quantities of the compounds of Formula II beyond that point does not produce a corresponding shift in the absorption characteristics.
  • the optimum amount of the compound of Formula II employed in my invention can vary, depending upon-the effect desired.
  • the most advantageous amounts of the sensitizing dye and the compound of Formula II can be determined by running a series of test emulsions wherein various quantities of either ingredient are employed.
  • the amount of sensitizing dye used can vary rather widely and I have found that from about 5 to about 200 mg. per mole of silver halide are quite adequate.
  • the amount of compound of Formula II can likewise be varied, as described above, and I have found that from about 10V to about 200 mg. per mole of silver halide of the compounds of Formula II are quite adequate.
  • VThe ratio of the amount of sensitizing dye to the compound of Formula II can likewise be varied, and I have found that, in general, this ratio can vary from about 1:5 to about 5:1 (by. weight).
  • the emulsions can then be digested for a short period of time prior to coating on a suitable support, such asv glass, cellulose derivative iilm, metal, paper, polyvinyl .acetal film, etc. After coating to a suitable thickness, the film can then be allowed to dry.
  • a suitable support such asv glass, cellulose derivative iilm, metal, paper, polyvinyl .acetal film, etc.
  • My invention is primarily directed to the ordinarily employed gelatino-silvenhalide developing-out emulsions, e.g., gelatino-silver-chloride, -chlorobromide, -chloroiodide, -chlorobromiodide, bromide and -bromiodide developing-out emulsions. While the results inthe following table were obtained using gelatino-silver-bromiodide emulsions, 'excellent vresults have 4also been obtained using gelatino-silver-chlorobromide emulsions.
  • Emulsions which form the latentrimage mostly inside the silver halide grains such as theI emulsions set forth in E. B.- Knott et al. U.S. Patent 2,456,956, dated December 21, V194,8, lcan also be employed in practicing my 'invention.
  • Photographic silver halide emulsions such as those listed above, containing the sensitizing combinations of my invention can also contain such addenda eis-chemical sensitizers, eg., sulfur sensitizers (eg, allyl thiocarbamide, thiourea, allylisothiocyanate, cystine, -etc.), various gold compounds (e.g., potassium chloroaurate, auric trichloride, etc.) (see U.S. Patents W. D. Baldsiefen 2,540,085, granted February 6, 1951; R. E. Damschroder 2,597,856, granted May 27, 1952 and H. C. Yutzy et al.
  • addenda eis-chemical sensitizers eg., sulfur sensitizers (eg, allyl thiocarbamide, thiourea, allylisothiocyanate, cystine, -etc.), various gold compounds (e.g., potassium chloroaurate, au
  • the Dye (a) of Table A produced a 275% increase in speed
  • emulsion used was a conventional gelatino-silver-bromioalthough there was a shift in absorption of only from dide emulsion and the coatings were prepared as de- 576 to 572 mp.. i scribed for Table A.
  • Exposure and development were As indicated above, many of the benzimidazolocarboidentical to that of Table A, the time of development cyanine dyes of my invention can be prepared according being about 4 minutes for each of the exposed coatings. to methods previously described in the prior art.
  • curve A represents the reectance (percent) for a processed ordinary gelatino-silver-bromiodide emulsion containing anhydro-5,5,6,6 tetrachlorol,ldiethyl 3,3'di(3su1fobutyl)benzimidazolocarbocyanine hydroxide
  • curve B represents the reectancef (percent) of the sensitized emulsion illustrated by curve A, butA to which 3-ethyl-2-(2-phenylimino-propylidene)--naphthoi thiazoline had been added.
  • the sensitometric properties of these coatings are illustrated in Examples 6 and 7 above.
  • curve C represents the reilectance (percent) of a processed ordinary gelatino-silver-bromiodide emulsion containing 5,5',6,6tetrach1oro1,l,3,3'tetraethyl benzimidazolocarbocyanine iodide
  • curve D represents the reectance (percent) of the emulsion represented by curve C, to which 1-methyl-2benzoylmethylene l-naphthothiazoline had been added.
  • the sensitometric .properties of these coatings yare shown in Examples 4 and 5 above.
  • my invention contemplates benzimidazolocarbocyanine dyes containing two chlorine atoms on a single benzene ring of the benzimidazole nucleus, regardless of their position on the ring. It is to be understood that my invention also contemplates benzimidazolocarbocyanine dyes containing no substituents on the benzene ring of the benzimidazole nucleus.
  • the reaction mixture was chilled and the solid filtered ol and then it was suspended in 60 ml. of water containing 2 g. of sodium iodide. After chilling for two hours, the crude dye was iiltered olf. The dye was suspended in 60% methyl alcohol and the suspension was heated to boiling and then cooled. After ltering, the dye was suspended in 60 ml. of methylV alcohol, cooled and tiltered. The dye was obtained as brownish crystals in a A6% yield, M.P. 205-206 C. with decomposition.
  • the reaction mixture was chilled and the solid filtered off and then it was suspended in 60 ml. of water containing 2 g. of sodium iodide. After standing for two hours, the crude dye was tiltered off. The' dye was dissolved in 400 ml. of 70% -methyl alcohol and one ml. of triethylamine, the solution was filtered and the filtrate made acid with glacial acetic acid. The pure dye was obtained as brownish-orange crystals in a 5% yield, M.P. 256 257 C. with decomposition.
  • the dye was suspended in 100ml, of ⁇ hot methyl alcohol, the suspension was ⁇ cooled and iiItered.
  • the dye was obtained as reddish crystals VAin a 25% yield, M.P. 294-295 C. with dei composition. f
  • Unsymmetrical benzimidazolocarbocyanine dyes useful'in my invention can be prepared as described in Gevaert Belgian Patent 532,735, vgranted November 13, 1954.
  • R3 each represents a member selected from the group consisting of an'alkyl group and an aryl group, d'and n each represents a positive integer of from 1 to 3, and.
  • X represents an acid radical, and (2) afcompound selected from those represented by the .following general formula.: l
  • R4 represents an alkyl group
  • R5 represents a member selected from the group consisting of an alkyl Vgroup and an aryl group
  • Q represents a member vselected sions.V sIonre wherein Di represents an alkylene group
  • R4 represents an alkyl group
  • R5 represents a member selected from the group consisting of an alkyl group and anlaryl group
  • Q represents a member selected from the group consisting of an oxygen atom and an arylimino group
  • Z represents the non-metallic ato-ms climas 11 e necessary to complete a heterocyclic nucleus selected from the group consisting of those of the naphthothiazoline series and those of the naphthoselenazoline series.
  • R and R1 each represents an alkyl group and X represents an acid radical, and (2) a compound selected from those represented by the following general formula: Y
  • R4 represents an alkyl group
  • R5 represents a member selected from the group consisting of an alkyl group and an aryl group
  • Q represents a member selected from the group consisting of an oxygen atom and an arylimino group
  • Z represents the nonmetallic atom's necessary to complete a heterocyclic nucleus selected from the group consisting of those of the naphthothiazoline series and those of the naphthoselenazoline series.
  • R4' represents an alkyl group
  • R5 represents a member selected from the group consisting of an alkyl group and an aryl group
  • Q represents a member selected from the group consisting of an oxygen' atom and an arylimino group
  • Z represents the nonmetallic atoms necessary to complete a heterocyclic nucleus selected from the group consisting of those ofthe naphthothiazoline series and those of the naphthoselenazoline series.
  • D represents an alkylene group
  • D represents an alkylene group
  • R4 represents an alkyl group
  • R5 represents a member selected from the group consisting of an alkyl group and an aryl group
  • Q represents a member selected from the ⁇ group consisting of an oxygen atom and an arylimino group
  • Z represents the non-metallic atoms necessary to complete a' heterocyclic nucleus selected vfrom the group consisting of those of the naphthothiazoline series and those of the naphthoselenazoline series.
  • R and R1 each represents an alkyl group and X represents an acid radical
  • R and R1 each represents an alkyl group and X represents an acid radical
  • R and R1 each represents an alkyl group and X represents an acid radical
  • R and R1 each represents an alkyl group and X represents an acid radical
  • R and R1 each represents an alkyl group and X represents an acid radical
  • R and R1 each represents an alkyl group and X represents an acid radical
  • R and R1 each represents an alkyl group and X represents an acid radical
  • R5 represents a member selected from the group consisting of an alkyl groupand an aryl group
  • Q represents a member selected 'from thegroup consisting of an oxygen atom and an arylimino group
  • Z represents the non-metallic atoms ,necessary/to Vcompletev a heterocyclic nucleus selected References Cited in the le of this patent UNITED STATES PATENTS f 2,1 12,139

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  • Chemical Kinetics & Catalysis (AREA)
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US743069A 1958-06-19 1958-06-19 Green sensitization of photographic silver halide emulsions Expired - Lifetime US2945763A (en)

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US743069A US2945763A (en) 1958-06-19 1958-06-19 Green sensitization of photographic silver halide emulsions
GB20535/59A GB914256A (en) 1958-06-19 1959-06-16 Sensitized photographic silver halide emulsions
FR797986A FR1228644A (fr) 1958-06-19 1959-06-19 Nouvelle émulsion photographique chromatisée

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3443955A (en) * 1965-05-21 1969-05-13 Ferrania Spa Sensitized silver halide emulsions
US3506443A (en) * 1965-11-18 1970-04-14 Eastman Kodak Co Color photographic elements and process
US3663211A (en) * 1969-07-02 1972-05-16 Gaf Corp Silver halide emulsions containing unsymmetrical trimethine sensitizing dyes
US3793020A (en) * 1966-08-30 1974-02-19 Fuji Photo Film Co Ltd Photographic silver halide emulsions sensitized with benzimidazole cyanine dyes
US3994733A (en) * 1973-12-10 1976-11-30 Fuji Photo Film Co., Ltd. Silver halide photographic emulsion
US4147553A (en) * 1977-02-10 1979-04-03 Fuji Photo Film Co., Ltd. Supersensitized photographic emulsion
US4581329A (en) * 1983-03-11 1986-04-08 Fuji Photo Film Co., Ltd. Silver halide photographic light-sensitive material
EP0200502A2 (de) 1985-04-30 1986-11-05 Konica Corporation Lichtempfindliches farbphotographisches Silberhalogenidmaterial
EP0202616A2 (de) 1985-05-16 1986-11-26 Konica Corporation Verfahren zur Farbentwicklung eines photographischen lichtempfindlichen Silberhalogenidmaterials
US5354646A (en) * 1986-03-26 1994-10-11 Konishiroku Photo Industry Co., Ltd. Method capable of rapidly processing a silver halide color photographic light-sensitive material

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2112139A (en) * 1935-07-05 1938-03-22 Eastman Kodak Co Acylmethylene derivatives of arylothiazolines and aryloselenazolines
US2298732A (en) * 1940-12-16 1942-10-13 Eastman Kodak Co Polymethine base
US2694638A (en) * 1953-08-13 1954-11-16 Eastman Kodak Co Supersensitization of carbocyanine dyes with hemicyanine bases
US2739149A (en) * 1953-02-27 1956-03-20 Eastman Kodak Co Symmetrical carbocyanine dyes
US2778823A (en) * 1954-08-23 1957-01-22 Eastman Kodak Co Benzimidazolocarbocyanine dyes

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2112139A (en) * 1935-07-05 1938-03-22 Eastman Kodak Co Acylmethylene derivatives of arylothiazolines and aryloselenazolines
US2298732A (en) * 1940-12-16 1942-10-13 Eastman Kodak Co Polymethine base
US2739149A (en) * 1953-02-27 1956-03-20 Eastman Kodak Co Symmetrical carbocyanine dyes
US2694638A (en) * 1953-08-13 1954-11-16 Eastman Kodak Co Supersensitization of carbocyanine dyes with hemicyanine bases
US2778823A (en) * 1954-08-23 1957-01-22 Eastman Kodak Co Benzimidazolocarbocyanine dyes

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3443955A (en) * 1965-05-21 1969-05-13 Ferrania Spa Sensitized silver halide emulsions
US3506443A (en) * 1965-11-18 1970-04-14 Eastman Kodak Co Color photographic elements and process
US3793020A (en) * 1966-08-30 1974-02-19 Fuji Photo Film Co Ltd Photographic silver halide emulsions sensitized with benzimidazole cyanine dyes
US3663211A (en) * 1969-07-02 1972-05-16 Gaf Corp Silver halide emulsions containing unsymmetrical trimethine sensitizing dyes
US3994733A (en) * 1973-12-10 1976-11-30 Fuji Photo Film Co., Ltd. Silver halide photographic emulsion
US4147553A (en) * 1977-02-10 1979-04-03 Fuji Photo Film Co., Ltd. Supersensitized photographic emulsion
US4581329A (en) * 1983-03-11 1986-04-08 Fuji Photo Film Co., Ltd. Silver halide photographic light-sensitive material
EP0200502A2 (de) 1985-04-30 1986-11-05 Konica Corporation Lichtempfindliches farbphotographisches Silberhalogenidmaterial
EP0202616A2 (de) 1985-05-16 1986-11-26 Konica Corporation Verfahren zur Farbentwicklung eines photographischen lichtempfindlichen Silberhalogenidmaterials
US5354646A (en) * 1986-03-26 1994-10-11 Konishiroku Photo Industry Co., Ltd. Method capable of rapidly processing a silver halide color photographic light-sensitive material

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GB914256A (en) 1963-01-02
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