US2159565A - Photographic emulsion - Google Patents

Photographic emulsion Download PDF

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Publication number
US2159565A
US2159565A US120967A US12096737A US2159565A US 2159565 A US2159565 A US 2159565A US 120967 A US120967 A US 120967A US 12096737 A US12096737 A US 12096737A US 2159565 A US2159565 A US 2159565A
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United States
Prior art keywords
dyes
cyanine
dye
iodide
diethyl
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US120967A
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English (en)
Inventor
Charles E K Mees
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Eastman Kodak Co
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Eastman Kodak Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to BE431847D priority Critical patent/BE431847A/xx
Priority to BE343344D priority patent/BE343344A/xx
Application filed by Eastman Kodak Co filed Critical Eastman Kodak Co
Priority to US120967A priority patent/US2159565A/en
Priority to FR840957D priority patent/FR840957A/fr
Priority to BE420798D priority patent/BE420798A/xx
Priority to DEK146045D priority patent/DE737686C/de
Priority to US169187A priority patent/US2159038A/en
Priority to US169186A priority patent/US2159037A/en
Priority to GB14173/38A priority patent/GB515789A/en
Priority to DEK154399D priority patent/DE720343C/de
Priority to FR51209D priority patent/FR51209E/fr
Application granted granted Critical
Publication of US2159565A publication Critical patent/US2159565A/en
Priority to GB15972/39A priority patent/GB530690A/en
Priority to FR51482D priority patent/FR51482E/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D3/00—Electroplating: Baths therefor
    • C25D3/02—Electroplating: Baths therefor from solutions
    • C25D3/04—Electroplating: Baths therefor from solutions of chromium
    • 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

  • This invention relates to sensitized photographic emulsions and more particularly to photographic emulsions, such as those of the gelatino-silver-halidetype, containing a mixture or combination of two or more .sensitizing materials, at. least one of which cooperates with at least one other to alter the sensitivity of the emulsion to a greater degree than is possible with any one of the sensitizing materials alone.
  • the sensitization produced by my combination is always greater, in some spectral region, than the sum total of the sensitizations produced by the separate sensitizing materials.
  • the sensitizing'materials of my combinations are substances generally referred to as dyes and more particularly as dyes of the cyanine class.
  • the combined effect is no greater than the effect of a single one of the dyes emplayed in a concentration equal to the sum of the concentrations of all the dyes in the combination. Very frequently, the combined effect of two dyes is less than that of one of them alone.
  • the magnitude of the supersensitization depends 15 upon the relative and absolute concentrations of the dyes in the emulsion and on the type of emulsion. By suitable choice of conditions supersensitizationcan always be made to assume values which are readily observable. 20
  • An object of my invention is to provide photographic emulsions containing a su- 5 I shall 50 persensitizing combination of eyanine dyes.
  • a further object is to provide a process for sensitizing photographic emulsions with supersensitizing combinations of cyanine dyes and to provide a method of increasing the sensitivity of photographic emulsions sensitized with cyanine dyes.
  • a still further object is to provide a photographic element comprising a support coated with such supersensitized emulsions.
  • the dyes which I employ in my supersensitizing mixtures are sensitizers of photographic emulsions when used alone. While there is more than one manner of formulating and naming the dyes which I employ in practicing my invention, it is believed that the'formulas,
  • oxathiazoloand oxaselenazolocarbocyanine dyes useful in practicing my -in vention are the following:
  • oxathiazolocarbocyanines which can be represented by the following general formula:
  • R and R represent alkyl groups and X represents an acid radical.
  • the benzoxazole nucleus can be substituted with simple substituents which do not interfere with sensitizing properties, such for example as chloro, alkyl or alkoxy.
  • dye-iodides where X represents iodine.
  • other dye-salts can be employed, such for example as the chlorides; bromides, perchlorates, alkylsulfates or alkyl-p-toluenesulfonates.
  • R and R represent alkyl groups of at least two carbon atoms.
  • the dyes wherein R and R represent ethyl are especially useful.
  • Oxathiazolocarbocyanine and oxaselenazolocarbocyanine dyes can be prepared by reacting a Z-methylthiazole or a 2-methylse1enazole base with an equimolecular proportion of an alkylp-toluenesulfonate, e. g., ethyl-p-toluenesulfonate, by heating for several hours (advantageously 4 or 5 days) at about to C.
  • the crude so-prepared quaternary salt is then reacted with a l-(B-acetanilidovinyl)-benzoxaz0le alkyl quaternary salt, e.
  • the crude quaternary salt is advantageously employed in an excess of about 20%.
  • the quantity of pyridine is conveniently about 10 cc. for each gram of Z-methylthiazole or Z-methylselenazole base used.
  • the pyridine reaction mixture is concentrated by removing a portion of the pyridine under vacuum.
  • About two-liters of diethyl ether is then added to the residuum to form a solution from which the dye separates upon chilling after standing.
  • the dye can be recrystallized from methyl alcohol after washing with a little water and acetone.
  • the 2 methylselenazole bases are described in U. S. Patent No. 2,005,411, dated June 18, 1935.
  • the 2,2'-cyanine dyes which can be represented by the following general formula:
  • thia-2'-cyanine dyes which can be represented by the following general formula:
  • the selena-2'-cyanine dyes which can be represented by the following general formula:
  • the benzothia-2'-cyanine dyes which can be represented by the following general formula:
  • oxazo1o-2-cyanine dyes which can be represented by the following general formula:
  • thiazolo-2-cyanine dyes which can be represented by the following general formula:
  • R and R represent alkyl groups and X represents an acid radical.
  • X represents iodine
  • other pseudocyanine salts can be employed, such for example as the chlorides, bromides, perchlorates, alkylsulfates or alkyl-ptoluene-sulfonates.
  • R and R represent an alkyl group of from one to four carbon atoms.
  • the dyes wherein R and R represent ethyl are particularly useful in practicing my invention.
  • the pseudocyanine dyes are particularly useful in practicing my invention.
  • the oxazolo-2Ecyanines and thiazolo-2'-cyanines can be substituted in the five position with substituents such as alkyl groups or aryl groups of the benzene series, for example phenyl.
  • the selenazolo-2'-cyanine dye can also be employed in my supersensitizing combination, though less advantageously.
  • the dye-iodide exemplified by the dye-iodide, with one or more of the following:
  • 2,1-diethylthia-2-cyanine iodide 2,1-diethyl-3,4-benzothia-2'-cyanine bromide.
  • 2,1-diethyl-4-chlorothia-2-cyanine iodide 1,1-diethyl-2,2'-cyanine iodide.
  • 1,l-diethyl-2,2-cyanine iodide 2,1-diethylthia-2'-cyanine iodide. 2,1'-diethyl-3,4-benzothia-2'-cyanine bromide. 2,1-diethyl-6-methyl-3,4-benzothia-2 cyanine iodide. 2,1-diethyl-4-chlorothia-2'-cyanine iodide. 3,1'-diethyl-4-phenylthiazolo-2-cyanine iodide. 3,1-diethyl-4-phenyloxazolo-2-cyanine iodide.
  • oxathiazoloand oxaselenazolocarbocyanines can be substituted in the trimethenyl chain with alkyl groups, such as in the case of 2,3'-diethyl 4,9-dimethyloxathiazolocarbocyanine salts, without departing from the scope of my invention.
  • Those oxathiazoloand oxaselenazolocarbocyanines containing methyl groups on the nitrogen atoms, such as in the case of 2ethyl-3,4-dimeth yloxathiazoloor selenazolocarbocyanine salts are generally less satisfactory in practicing my invention.
  • the oxathiazolocarbocyanine and oxaselenazolocarbocyanine dyes containing methyl groups on the nitrogen atoms can be combined with 2,2'-cya nine dyes and sulfur-containing pseudocyanine dyes to successfully practice my invention.
  • Thoseoxathiazolo-and oxaselenazolocarbocyanine dyes containing an aryl group of the benzene series, such as phenyl, in the thiazole or selenazole nucleus are, likewise, less satisobjectives of my invention can be attained as illustrated under II above by combining 4-phenyl dyes with '2,'2-cyanine dyes, or sulfur-containing pseudocyanine dyes.
  • Pseudocyanine dyes containing the 5,6-ben zothia nucleus are usually of lesser utility in practicing my invention.
  • oxazolo-, thiazoloand selenazolo-2-cyanines those substituted in the four position of the oxazole, thilenazolocarbocyanine is the supersensitizer.
  • my combinations can as well contain one oxathiazoloor oxaselenazolocarbocyanine cooperating with two or more pseudo cyanine dyes. contain one pseudocyanine dye cooperating with two or more oxathiazoloor oxaselenazolocarbocyanine dyes.
  • the objects of my invention can be accom plished by merely incorporating the appropriate dyes in an ordinary photographic emulsion of; My invention is par-" ordinary concentration. ticularly directed to the ordinarily employed gelatino-silver-halide emulsions. "However, my supersensitizing combinations can be employed in emulsions in which the carrier is other than gelatin, for example, a resinous substance or cellulosic derivative which has substantially no deleterious'effect on the light sensitive materials.
  • the carrier is other than gelatin, for example, a resinous substance or cellulosic derivative which has substantially no deleterious'effect on the light sensitive materials.
  • 'dyes were generally employed in concentrations of the order of 10 mgs. each per liter of ordinary emulsion, but can be employed in concentrations several times greater or less than that.
  • the ratio of concentration of the carbocyanine dye to the concentration of pseudocyanine dye may be varied widely from 10:1 to 1:10, for example. The most favorable conditions for supersensitization of the desired magnitude must be determined by experiment, the manner of which will be'apparent to those skilled in the art, upon a complete perusal of these specifications.
  • the method of incorporating dyes in emulsions are simple and well known to those skilled in the art.
  • the solvent must, of course, be compatible with the emulsion, substantially free from any deleterious effect onthe light sensitive materials and capable of dissolving the dyes.
  • my comb'nations can Methanol has proven satisfactory as a solvent for the dyes in practicing my invention.
  • the dyes are advantageously incorporated in the finished, washed emulsion and should be uniformly distributed throughout the emulsion.
  • the emulsion can then be converted into a photographic element by coating upon a support, such as glass, cellulose acetate, cellulose nitrate, other cellulose derivative or resin, in a manner well known in the art.'
  • curve A represents the sensitivity of an ordinary gelatino-silverbromide emulsion containing 2,3-diethyloxathiazolocarbocyanine iodide in a concentration of about 10 mg. per liter of emulsion
  • curve B represents the sensitivity of the same emulsion containing 1,1"-diethyl-2,2'-cyanine iodide in a concentration of about 20 mg. per liter of emulsion
  • curve C represents the sensitivity of the same emulsion containing 2,3'-diethyloxathiazolocarbocyanine iodide and 1,1-diethyl-2,2'-cyanine iodide in concentrations of 10 mg. and 20 mg. per liter emulsion, respectively.
  • the sensitivity of the emulsion represented by curve C is about six times that of the emulsion represented by curve A.
  • curve D represents the sensitivity of a silver bromide emulsion containing 2,3 dii ethyloxathiazolocarbocyanine iodide in a concentration of about 10 mg. per liter
  • curve E represents the same emulsion containing 3,1'-diethyll-phenyloxazolo-Zcyanine iodide in a concen tration of about 20 mg. per liter of emulsion
  • curve F represents the sensitivity of the same emulsion containing 2,3'-diethyloxathiazolocarbocyanine iodide and 3,l'-diethyl-4-phenylox- -azolo-2-cyanine iodide in concentrations of 16 mg. and 20 mg. per liter of emulsion, respectively.
  • the sensitivity of the emulsion represented by curve F is about five times that of the emulsion represented by curve D.
  • curve G represents the sensitivity of a silver bromide emulsion containing 2,3-diethyloxathiazolocarbocyanine iodide in a concentration of about 3 mg. per liter of emulsion
  • curve H represents the same emulsion containing 2,1'-diethyl-thia-2'-cyanine iodide in a concentration of about 10 mg. per liter of emulsion
  • curve I represents the sensitivity of the same emulsion containing 2,3 diethyloxathiazolocarbocyanine iodide and 2,1-diethyl-thia-2'-cyanine iodide in concentration of about 3 mg. and 10 mg. per liter of emulsion, respectively.
  • the sensitivity of the emulsion represented by curve I is over three times that of the emulsion represented by curve G.
  • curve J represents the sensitivity of a bromide emulsion containing 2,3'-di ethyl-4-. methyloxathiazolocarbocyanine iodide in a concentration of about 10 mg. per liter
  • curveK represents the sensitivity of the same emulsion containing 1,1'-diethyl-2,2-cyanine iodide in a concentration of about 20 mg. per liter
  • curve L represents the sensitivity of the same emulsion containing 2,3 -diethyl-4 -methyloxathiazolocarbocyanine iodide and 1,1'-diethyl-2,2-cyanine iodide in concentrations of about 10 mg. and 20 mg. per liter, respectively.
  • the sensitivity of the emulsion represented by curve L is about six times that of the emulsion represented by curve J.
  • curve M represents the sensitivity of a bromide emulsion containing 2,3-diethyl-4'- methyloxathiazolocarbocyanine iodide in a concentration of about 10 mg. per liter of emulsion
  • curve N represents the sensitivity of the same emulsion containing 3,1-diethyl 4 phenyloxa bromide emulsion containing 2,3-diethyl-4'-* methyloxaselenazolo-carbocyanine iodide in a concentration of about 10 mg, per liter
  • curveQ represents the sensitivity of the same emulsion containing 1,1'-diethyl-2,2'-cyanine iodide in a concentration of about 20 mg.
  • curve R represents the sensitivity of the same emulsion. containing 2,3-diethyl -4' methyloxaselenazolm carbocyanine iodide and 1,1'-diethyl-2,2'-cyanine iodide in concentrations of 10 mg. and 20 mg.
  • curve S represents the sensitivity of a bromide emulsion containing 2,3-diethyl-4- methyloxaselenazolocarbocyanine iodide in a concentration of about 10 mg. per liter
  • curve T represents the same emulsion containing 3.1'-diethyl-4-phenyloxazolo-2'-cyanine iodide in a concentration of about 20 mg. per liter
  • curve U represents the same emulsion containing 2,3'-diethyl-4'-methyloxaselenazolocarbocyanine iodide and 3,1 diethyl 4 phenyloxazolo-2 cyanlne iodide in concentrations of 10 mg. and 20 mg. per liter, respectively.
  • the sensitivity of the emulsion represented by curve U is about 35% greater than that of the emulsion represented by curve S.
  • curve V represents a bromide emulsion containing 2.3-diethyl-4-methyloxaselenazolocarbocyanine iodide in a concentration of about 3 mg. per liter
  • curve W represents the same emulsion containing 2,1'-diethyl-thia-2'- cyanine iodide in a concentration of about 10 mg. per liter
  • curve X represents the same emulsion containing 2.3'-diethyl-4-methyloxaselenazolocarbocyanine iodide and 2,1-diethy1-2-cyanine iodide in concentrations of 3 mg. and 10 mg. per liter. respectively.
  • a photographic gelatino-silver-halide emuldialkyl-4-phenyloxazolo-2-cyanine dye in which sion containing a supersensitizing combination of at least one sensitizing 2,3'-diethyl-4-methyloxaselenazolocarbocyanine halide with at least one sensitizing 1,1-diethyl-2,2'-cyanine halide.
  • the 3 and 1'-alkyl groups each contain from one to four carbon atoms.

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  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Electrochemistry (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Silver Salt Photography Or Processing Solution Therefor (AREA)
  • Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
  • Plural Heterocyclic Compounds (AREA)
  • Heterocyclic Carbon Compounds Containing A Hetero Ring Having Nitrogen And Oxygen As The Only Ring Hetero Atoms (AREA)
US120967A 1937-01-16 1937-01-16 Photographic emulsion Expired - Lifetime US2159565A (en)

Priority Applications (13)

Application Number Priority Date Filing Date Title
BE431847D BE431847A (de) 1937-01-16
BE343344D BE343344A (de) 1937-01-16 1927-07-20
US120967A US2159565A (en) 1937-01-16 1937-01-16 Photographic emulsion
FR840957D FR840957A (fr) 1937-01-16 1937-03-27 Procédé pour sensibiliser les émulsions photographiques en résultant
BE420798D BE420798A (de) 1937-01-16 1937-03-28
DEK146045D DE737686C (de) 1937-01-16 1937-03-31 Verfahren zum UEbersensibilisieren von Halogensilberemulsionen mit Mischungen von sensibilisierenden Cyaninfarbstoffen
US169187A US2159038A (en) 1937-01-16 1937-10-15 Photographic emulsion
US169186A US2159037A (en) 1937-01-16 1937-10-15 Photographic emulsion
GB14173/38A GB515789A (en) 1937-01-16 1938-05-12 Improvements in sensitized photographic emulsions
DEK154399D DE720343C (de) 1937-01-16 1939-05-09 Verfahren zur Steigerung der Empfindlichkeit von photographischen Halogensilberemulsionen
FR51209D FR51209E (fr) 1937-01-16 1939-05-12 Procédé pour sensibiliser les émulsions photographiques et émulsions photographiques en résultant
GB15972/39A GB530690A (en) 1937-01-16 1939-05-30 Improvements in sensitized photographic emulsions
FR51482D FR51482E (fr) 1937-01-16 1940-05-30 Procédé pour sensibiliser les émulsions photographiques et émulsions photographiques en résultant

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US120967A US2159565A (en) 1937-01-16 1937-01-16 Photographic emulsion
US169187A US2159038A (en) 1937-01-16 1937-10-15 Photographic emulsion
US169186A US2159037A (en) 1937-01-16 1937-10-15 Photographic emulsion
GB15972/39A GB530690A (en) 1937-01-16 1939-05-30 Improvements in sensitized photographic emulsions

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US169187A Expired - Lifetime US2159038A (en) 1937-01-16 1937-10-15 Photographic emulsion
US169186A Expired - Lifetime US2159037A (en) 1937-01-16 1937-10-15 Photographic emulsion

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US169186A Expired - Lifetime US2159037A (en) 1937-01-16 1937-10-15 Photographic emulsion

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BE (3) BE343344A (de)
DE (2) DE737686C (de)
FR (3) FR840957A (de)
GB (2) GB515789A (de)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE742343C (de) * 1940-10-25 1943-12-07 Ig Farbenindustrie Ag Verfahren zum optischen UEbersensibilisieren photographischer Emulsionen
US2432468A (en) * 1945-12-29 1947-12-09 Eastman Kodak Co Supersensitized silver halide emulsion
US2892837A (en) * 1955-08-22 1959-06-30 Sperry Rand Corp Preparation of 2-methyl-4, 5, 6, 7-tetrahydrobenzoxazole and cyanine dyes therefrom
US5389505A (en) * 1992-09-18 1995-02-14 Fuji Photo Film Co., Ltd. Silver halide photographic material

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE968111C (de) * 1943-05-28 1958-01-16 Agfa Ag Fuer Photofabrikation Verfahren zur Sensibilisierung von Halogensilberemulsionen
US3364031A (en) * 1963-06-24 1968-01-16 Eastman Kodak Co Supersensitized photographic silver halide emulsions

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE742343C (de) * 1940-10-25 1943-12-07 Ig Farbenindustrie Ag Verfahren zum optischen UEbersensibilisieren photographischer Emulsionen
US2432468A (en) * 1945-12-29 1947-12-09 Eastman Kodak Co Supersensitized silver halide emulsion
US2892837A (en) * 1955-08-22 1959-06-30 Sperry Rand Corp Preparation of 2-methyl-4, 5, 6, 7-tetrahydrobenzoxazole and cyanine dyes therefrom
US5389505A (en) * 1992-09-18 1995-02-14 Fuji Photo Film Co., Ltd. Silver halide photographic material

Also Published As

Publication number Publication date
BE343344A (de) 1927-08-31
GB515789A (en) 1939-12-14
DE737686C (de) 1943-07-21
FR840957A (fr) 1939-05-08
US2159038A (en) 1939-05-23
BE431847A (de)
GB530690A (en) 1940-12-18
BE420798A (de) 1937-04-30
DE720343C (de) 1942-05-06
FR51482E (fr) 1942-08-12
US2159037A (en) 1939-05-23
FR51209E (fr) 1941-12-20

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