US3639127A

US3639127A - Silver halide emulsions containing a dye derived from 4,6-diaryl substituted picolinium salts as desensitizer

Info

Publication number: US3639127A
Application number: US57831A
Authority: US
Inventors: Leslie G S Brooker; Daniel S Daniel; Robert C Taber
Original assignee: Eastman Kodak Co
Current assignee: Eastman Kodak Co
Priority date: 1970-07-23
Filing date: 1970-07-23
Publication date: 1972-02-01
Anticipated expiration: 1989-02-01
Also published as: FR2103210A5; GB1366506A; CA981516A

Abstract

Photographic silver halide emulsions containing cyanine, styryl and merocyanine dyes derived from 4,6-diaryl substituted picolinium salts, which either sensitize or desensitize silver halide emulsions and photographic elements containing said emulsions are described. 3''-Ethyl-1,4,6-triphenyl-2pyridothiacyanine iodide, 2-(3-nitrostyryl)-1,4,6triphenylpyridinium iodide and 3-ethyl-5-((1,4,6-tri(-methoxyphenyl)-2(1H)-pyridylidene)-ethylidene) rhodanine are illustrative of the dye compounds employed.

Description

0 United States Patent [151 3,639,127 Brooker et al. 1 Feb. 11, 1972 [54] SILVER HALIDE EMULSIONS [56] References Cited g 'mgi gguigglFrgfg FROM UNITED STATES PATENTS 4, -0

1,994,170 3 1935 Dab 1 ..96 101 X PICOUMUM SALTS AS DESENSITIZER 2,984,664 slim Fry ..260 /240.5 [72] Inventors: Leslie G. S. Brooker; Daniel S. Daniel;

Robe" C. Tab", 3 of Rochester, NY Primary Examiner-Norman G. Torchln Assistant Examiner -won H. Louie, Jr. [73] Assignee: Eastman Kodak Company, Rochester, Attorney-W. H. J. Kline and William E. Neely NY. [22] Filed: July 23,1970 [57] ABSTRACT Photographic silver halide emulsions containing cyanine, [21] 57831 styryl and merocyanine dyes derived from 4,6-diaryl substituted picolinium salts, which either sensitize or desensitize 52 U.S. en ..96/l01, 96/102, 260/240, silver halide emulsions and Photographic elements containing 2 24 5 said emulsions are described. 3'-Ethyl-1,4,6-triphenyl-2- pyridothiacyanine iodide, 2-(3-nitrostyryl)-1,4,6-triphenyl- 51] lm. C1. ..G03c1/36,G03c 1/08 py i q iodide and y -HIAb-lrfl-merhoxy- 5s FieldofSearch ..96/101,102; 260/240, 240.5 y )-py y ly rhodanine are tive of the dye compounds employed.

19 Claims, No Drawings SILVER HALIDE EMULSIONS CONTAINING A DYE DERIVED FROM 4,6'DIARYL SUBSTITUTED PICOLINIUM SALTS AS DESENSITIZER This invention relates to photographic silver halide emulsions containing cyanine, styryl and merocyanine dyes derived from 4,6-diaryl substituted picolinium salts, which either sensitize or desensitize silver halide emulsions and to photo graphic elements containing said emulsions.

The dyes present in the photographic silver halide emulsions and photographic elements of our invention include those having the following general formulas:

wherein d, g and n each represents a positive integer of from one to two,m represents a positive integer of from one to four, p represents a positive integer of from one to three, R represents a phenyl nucleus (including substituted phenyl) such as phenyl, an alkylphenyl preferably containing from one to four carbon atoms in the alkyl portion such as pmethylphenyl, p-ethylphenyl, p-propylphenyl, pisopropylphenyl, p-butylphenyl, m-methylphenyl, ethylphenyl, etc., an alkoxyphenyl preferably containing from one to five carbon atoms in the alkoxy portion such as pmethoxyphenyl, p-ethoxyphenyl, p-propoxyphenyl, pisopropoxyphenyl, p-butoxyphenyl, p-pentyloxyphenyl, mmethoxyphenyl, m-ethoxyphenyl, m-propoxyphenyl, m-butoxyphenyl, m-pentyloxyphenyl, 2,5-dimethoxyphenyl, 2,5- diethoxyphenyl, 2,5-dipentyloxyphenyl, etc., a halogen substituted phenyl such as p-chlorophenyl, p-bromophenyl, pfluorophenyl, m-chlorophenyl, 3,4-dichlorophenyl, etc,, a nitrophenyl such as p-nitrophenyl, o-nitrophenyl, etc., and the like, R represents an alkyl group such as methyl, ethyl, propyl, isopropyl, butyl, see-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dododecyl, etc., especially an alkyl group having one to four carbon atoms, allyl, a sulfoalkyl group such as B-sulfoethyl, 'y-sulfopropyl, -y-sulfobutyl or wsulfobutyl, for example, a hydroxyalkyl group such as B hydroxyethyl, 'y-hydroxypropyl or w-hydroxybutyl, for example, an alkoxyalkyl group such as B-methoxyethyl, fi-ethoxyethyl, fi-propoxyethyl, y-methoxypropyl or 'y-ethoxypropyl, for example, a carboxyalkyl group such. as carboxymethyl, B- carboxyethyl, y-carboxypropyl or w-carboxybutyl, for example, an alkanoyloxyalkyl group such as B-acetoxyethyl, B- propionyloxyethyl, 'y-acetoxypropyl, w-acetoxybutyl or w-butyryloxybutyl, for example, an alkoxycarbonylalkyl group such as methoxycarbonylmethyl, B-methoxycarbonylethyl, B- ethoxycarbonylethyl, y-ethoxycarbonylpropyl or m-ethoxycarbonylbutyl, for example, an aralkyl group such as benzyl or phenethyl, for example, or an aryl group (including substituted aryl) such as phenyl, tolyl, chlorophenyl, sulfophenyl or carboxyphenyl, for example, R represents a dialkylamino group, preferably in the 4-position on the phenyl nucleus and containing from two to about 10 carbon atoms, such as dimethylamino, diethylamino, methylethylamino, dipropylamino, diisopropylamino or dibutylamino, for example, or a nitro group preferably in the 3-position on the phenyl nucleus, X represents an acid anion, e.g., chloride, bromide, iodide, thiocyanate, sulfarnate, methyl sulfate, ethyl sulfate, perchlorate, benzenesulfonate, p-toluenesulfonate, etc., A represents a monovalent group such as a hydroxyalkyl group preferably containing from two to four carbon atoms, e.g., B- hydroxyethyl, y-hydroxypropyl, w-hydroxybutyl, etc., a dialkylamino group preferably containing from two to about 10 carbon atoms, e.g., dimethylamino, diethylamino, methylethylamino, dipropylamino, diisopropylamino, dibutylamino, etc., a dialkylaminoalkyl group wherein each of said alkyl and dialkyl groups preferably contain from two to about 10 carbon atoms, e.g., dimethylaminoethyl, dimethylaminopropyl, diethylaminoethyl, diethylaminopropyl, dimethylaminodecyl, methylethylaminoethyl, etc., and the group (Boar V V wherein y represents a positive integer of from one to two and R represents a hydrogen atom or a substituent, preferably in the 4-position on the phenyl nucleus, such as an alkyl group preferably containing from one to four carbon atoms, e.g., methyl, ethyl, propyl, butyl, etc., an alkoxy group preferably containing from one to four carbon atoms, e.g., methoxy, ethoxy, propoxy, butoxy, etc., a halogen atom, e.g., chlorine, bromine, etc., a dialkylamino group preferably containing from two to about 10 carbon atoms, e.g., dimethylamino, diethylamino, methylethylamino, dipropylamino, diisopropylamino, dibutylamino, etc., a nitro group, a phenylazo group, an alkylthio group preferably containing from one to four carbon atoms, e.g., 'methylthio, ethylthio, propylthio, isopropylthio, butylthio, etc., or a heterocyclic nucleus, e.g., 2-methyl-5 (or 6) -benzothiazolyl, 2-methyl-5 (or 6)-benzoxazolyl, 2methyl-5 (or 6) -benzimidazolyl, etc., A, represents a member selected from A when n is l, and a divalent alkylene group preferably containing from two to 10 carbon atoms, e.g., ethylene, propylene, 1,3-propylene, 1,4- butylene, 1,6-hexamethylene, etc., when n is 2, 2 represents the nonmetallic atoms required to complete a 5 to 6-membered heterocyclic nucleus, such as those selected from the class consisting of a thiazole nucleus (e.g., thiazole, 4- methylthiazole, 4 phenylthiazole, S-methylthiazole, S-phenylthiazole 4,5-dimethylthiazole, 4,5-diphenylthiazole, 4-(2- thienyl)thiazole, etc., a benzothiazole nucleus, (e.g., benzothiazole, 4-chlorobenzothiazole, S-chlorobenzothiazole, -chlorobenzothiazole, 7-chlorobenzothiazole, 4-methylbenzothiazole, S-methylbenzothiazole, 6-methylbenzothiazole, S-bromobenzothiazole, 6-bromobenzothiazole, 4-phenylbenzothiazole, 5-phenylbenzothiazole, 4-methoxybenzothiazole, S-methoxybenzothiazole, o-methoxybenzothiazole, S-iodobenzothiazole, o-iodobenzothiazole, 4- ethoxybenzothiazole, S-ethoxybenzothiazole, tetrahydrobenzothiazole, 5,6-dimethoxybenzothiazole, 5,6- dioxymethylenebenzothiazole, 5-hydroxybenzothiazolc, 6- hydroxybenzothiazole, etc.), a naphthothiazole nucleus, (e.g.,

a-naphthothiazole, ,B-naphthothiazole, S-methoxy, B- naphthothiazole, S-ethoxy-B-naphthothiazole, S-methoxy-anaphthothiazole, 7-methoxy-a-naphthothiazole, etc.), a thionaphtheno-7', 6', 4,5-thiazole nucleus (e.g., 4'-methoxythianaphtheno-7', 6', 4,5-thiazole, etc.), an oxazole nucleus (e.g., 4-methyloxazole, S-methyloxazole, 4-phenyloxazole, 4,5-diphenyloxazole, 4-ethyloxazole, 4,5-dimethyloxazole, 5 phenyloxazole, etc.), a benzoxazole nucleus (e.g., benzoxazole, S-chlorobenzoxazole, S-methylbenzoxazole, S-phenylbenzoxazole, 6-methylbenzoxazole, 5,6-dimethylbenzoxazole, 4,6-dimethylbenzoxazole, S-methoxybenzoxazole, S-ethoxybenzoxazole, S-chlorobenzoxazole, 6-methoxybenzoxazole, S-hydroxybenzoxazole, 6-hydroxybenzoxazole, etc.) a naphthoxazole nucleus (e.g., a-naphthoxazole, B-naphthoxazole, etc.), a selenazole nucleus (e.g., 4-methylselenazole, 4- phenylselenazole, etc.), a benzoselenazole nucleus (e.g., benzoselenazole, S-chlorobenzoselenazole, S-methoxybenzoselenazole, S-hydroxybenzoselenazole, tetrahydrobenzoselenazole, etc), a naphthoselenazole nucleus (e.g., a-naphthoselenazole, B-naphthoselenazole, etc.), a thiazoline nucleus (e.g., thiazoline, 4-methylthiazoline, etc.), a Z-pyridine nucleus (e.g., Z-pyridine, S-methyI-Z-pyridine, etc.), a 4-pyridine nucleus (e.g., 4-pyridine, 3-methyl-4- pyridine, etc.), a 2-quinoline nucleus 2-quinoline, 3-methyl-2- quinoline, 5-ethyl-2-quinoline, 6-chloro-2-quinoline, 8- chloro-2-quinoline, 6-methoxy-2-quinoline, 8-ethoxy-2-quinoline, 8-hydroxy-2-quinoline, etc.), a 4-quinoline nucleus (e.g., 4-quinoline, 6-methoxy-4-quinoline, 7-methyl-4-quinoline, 8-chloro-4-quinoline, etc.), a l-isoquinoline nucleus (e.g., l-isoquiniline, 3,4-dihydro-l-isoquinoline, etc.), a 3-- isoquinoline nucleus (e.g., 3-isoquinoline, etc.), a 3,3-dialkylindolenine nucleus (e.g., 3,3-dimethylindolenine, 5- or 6- nitro-3,3-dimethyl-, or 5- or 6-cyano-3,S-dimethylindolenines, 3,3,S-trimethylindolenine, 3,3,7-trimethylindolenine, etc.), an imidazole nucleus (e.g., imidazole, l-alkylimidazole, l-alkyl- 4-phenylimidazole, l-alkyl-4,5-dimethylimidazole, etc.), a benzimidazole nucleus (e.g., benzimidazole, l-alkylbenzimidazole, l-aryl-5,-dichlorobenzimidazole, etc.), a napthimidazole nucleus (e.g., l-alkyl-a-naphthimidazole, laryl-B-naphthimidazole, l-alkyl-S-methoxy-anaphthimidazole, etc.), etc., and Q represents the nonmetallic' atoms required to complete a 5 to 6-membered heterocyclic nucleus selected from those including a 2-pyrazolin-5-one nucleus (e.g., 3-methyl-1-pheny1-2-pyrazolin-5-one, l-phenyl- 2-pyrazoline-5-one, l-(2-benzothiazolyl)-3-methyl-2- pyrazolin-S-one, etc.), an isoxazolone nucleus (e.g., 3-phenyl- 5(4l-l)-isoxazolone, 3-methyl-5-(4H)-isoxazolone, etc.), an oxindole nucleus (e.g., 1-a1kyl-2,3-dihydro-2-oxindoles, etc.), a 2,4,6-triketohexahydropyrirnidine nucleus (e.g., barbituric acid or 2-thiobarbituric acid as well as their l-alkyl (e.g., 1- methyl, l-ethyl, l-propyl, l-heptyl, etc.), or 1,34lialkyl (e.g., 1,3-dimethyl, 1,3-diethyl, 1,3-dipropyl, 1,3-diisopropyl, 1,3- dicyclohexyl, l,3-di(l3-methoxyethyl), etc.), or l,3-diaryl (e.g., l,3-diphenyl, 1,3-di(p-chlorophenyl), l,3-di(p-ethoxycarbonylphenyl), etc.), or l-aryl (e.g., l-phenyl, 1-pchlorophenyl, l-p-ethoxycarbonylphenyl), etc.) or 1-alkyl-3- aryl (e.g., l-ethyl-S-phenyl, l-n-heptyl-S-phenyl, etc.) derivatives), a rhodanine nucleus (i.e., a 2-thio-2,4-thiazolindinedione nucleus), such as rhodanine, S-aIkyl-rhodanines (e.g., 3-ethylrhodanine, 3-allylrhodanine, etc.), 3-carboxyalkylrhodanines (e.g., 3-(2-carboxyethyl)rhodanine, 3-(4-carboxybutyl)rhodanine, etc.), 3-sulfoalky1rhodanines (e.g., 3- (2-sulfoethyl)rhodanine, 3-(3-sulfopropyl)rhodanine, 3-(4- sulfobutyl)rhodanine, etc.), or 3-arylrhodanines (e.g., 3-phenyl-rhodanine, etc.), etc., a 2(3H)-imidazo-[1,2-a1pyridone nucleus, a 5,7-dioxo-6,7-dihydro-5-thiazolo-[3,2-a ]pyrimidine nucleus (e.g., 5,7-dioxo-3-phenyl-6,7-dihydro-5- thiazolo[3,2-a1pyrimidine, etc. a 2-thio-2,4-oxazolidinedione nucleus (i.e., a 2-thio-2,4( 3H,5H )oxazoledione nucleus) (e.g., 3-ethyl-2-thio-2, 4-oxazolidinedione, 3-(2-sulfoethyl)-2-thio-2,4-oxazolidinedione, 3-(4-sulfobutyl)-2-thio-2,4-oxazolidinedione, 3-(3-carboxypropyl)-2-thio-2,4 -oxazolidinedione, etc.), a thianaphthenone nucleus (e.g., 3-(2H)-thianaphthenone, etc. a 2-thio-2,5-thiazolidinedione nucleus (i.e., a 2-thio-2,S(3 H,4H)-thiazoledione nucleus) (e.g., 3-ethyl-2-thio-2,5- thiazolidinedione, etc.), a 2,4-thiazolidinedione nucleus (e.g., 2,4-thiazolidinedione, 3-ethyl-2,4-thiazolidinedione, S-phenyl-2,4,-thiazolidinedione, 3-oz-naphthyl-2,4-thiazolidinedione, etc.), a thiazolidinone nucleus (e.g., 4-thiazolidinone, 3-ethyl- 4-thiazolidinone, 3-phenyl-4-thiazolidinone, 3-a-naphthyl-4- thiazolidinone, etc.), a 2-thiazolin-4-one nucleus (e.g., 2- ethylmercapto-2-thiazolin-4-one, 2-alkylphenylamino-2- thiazolin-4-one, 2-diphenylamino-2-thiazolin-4-one, etc.), a 2- imino-4-oxazolidinone (i.e., pseudohydantoin) nucleus, a 2,4- imidazolidinedione (hydantoin) nucleus (e.g., 2,4- imidazolidinedione, 3-ethyl-2,4-imidazolidinedione, 3-phenyl- 2,4-imidazolidinedione, 3-a-naphthyl-2,4-imidazolidinedione, 1,3-diethyl-2,4-imidazolidinedione, l-ethyl-3-phenyl-2, 4- imidazolidinedione, I-ethyl-3-a-naphthyl-2,4- imidazolidinedione, 1,3-diphenyl-2,4-imidazolidinedione, etc.), a 2-thio-2, 4-imidazolidinedione (i.e., 2-thiohydantoin) nucleus (e.g., 2-thio-2,4-imidazolidinedione, 3-ethyl-2-thio- 2,4,-imidazolidinedione, 3-(4-sulfobutyl)-2-thio-2,4- imidazolidinedione, 3-(2-carboxyethyl)-2-thio-2,4- imidazolidinedione, 3-phenyl-2-thio-2,4-imidazolidinedione, 3-a-naphthyl-2- thio-2,4-imidazolidinedione, 1 ,3-diethyl-2- thio-2,4-imidazolidinedione, l-ethyl-3-phenyl-2-thio-2,4- imidazolidinedione, l-ethyl-3-a-naphthyl-2-thio-2,4- imidazolidinedione, l ,3-diphenyl-2-thio-2,4- imidazolidinedione, etc.), a 2-imidazolin-5-one nucleus (e.g.,

' 2-propylmercapto-2-imidazolin-5-one, etc.), etc. (especially a heterocyclic nucleus containing five atoms in the heterocyclic ring, three of said atoms being carbon atoms, one of said atoms being a nitrogen atom, and one of said atoms being selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom).

The above-defined dye compounds include both sensitizers and desensitizers for light-sensitive photographic silver-halide emulsions. Those that are sensitizers contain no desensitizing groups and are the preferred species, whereas those that are desensitizers always contain at least one strongly negative group such as a nitro or phenylazo substituent on a phenyl nucleus. All of the above compounds are crystalline and soluble in water and alcohol.

It is an object of the invention to provide photographic silver halide emulsions containing one or more of the dye compounds, described hereinbefore, and more especially containing those species of dyes which function as sensitizers. Another object is to provide photographic elements contain ing the new photographic emulsions of the invention. Other objects will become apparent hereinafter from a consideration of the description and appended claims.

We prepare the dye compounds defined by formulas I, ll, Ill and IV from the picolinium salt intermediates represented by the formulas:

- and wherein n, R, X, A and A are as previously defined. In general, the dyes are produced by heating a mixture of a quaternary salt of above formulas V or V1 with the appropriate intermediate. The reaction mixtures are heated to advantage in any suitable solvents used in dye synthesis including solvents such as ethanol, propanol, dioxane, pyridine, quinoline, and the like, at temperatures up to the reflux temperature of the mixture. Advantageously, the reaction is carried out in the presence of a basic condensing agent such as a tertiary amine, e.g., trimethylamine, triethylamine, tri-npropylamine, tri-n-butylamine, N-methylpiperidine, N-ethylpiperidine, N,N-dimethylaniline, N,N-diethylaniline, etc.

The symmetrical cyanine dyes of formula I are prepared to advantage by heating a mixture of a compound of formula V with diethoxymethyl acetate (forms carbocyanine), trimethoxypropene (forms dicarbocyanine), l-anilino-S- phenylimino-l,3-pentadiene hydrochloride (forms tricarbocyanine), etc., preferably in a solvent and in the presence of a tertiary amine such as mentioned above.

The unsymmetrical cyanine dyes of formula ll when n is are prepared advantageously by heating a mixture of a compound of formula V with a compound of the formula:

wherein G, 1R,,X and Z are as previously defined, g represents a positive integer of from one to two R represents an aryl group of from 67 carbon atoms, c.g., phenyl, p-tolyl, etc., and R represents an alkyl group of from 1-12 carbon atoms. This is preferably carried out in a suitable solvent and in the presence of a basic condensing agent. The unsymmetrical cyanine dyes of formula ll wherein n is 2 are prepared in generally similar manner from a mixture of a compound of formula Vl with formula VII.

The styryl dyes of formula [II are prepared to advantage by heating a mixture of a compound of formula V or formula V] with the appropriate N,N-disubstituted p-aminobenzaldehyde, N,N-disubstituted p-aminocinnamaldehyde, m-nitrobenzaldehyde, etc., preferably in a suitable solvent and in the presence of a basic condensing agent.

The merocyanine dyes of formula W are made to advantage by heating a mixture of a compound of formula V or formula VI with a compound of the formula:

VIII. Qx

wherein Q is as defined previously and W represents the group wherein p, R and R are as previously defined.

The preparation of the new photographic silver halide emulsions of our invention and the dyes incorporated in said emulsions is described hereinafter.

EXAMPLE l-2METHYL4,6-DIPHENYLPYRYLIUM IODIDE CH (B C1121 Sulfuric acid (30 ml.) was slowly added to acetic anhydride (100 ml.) and the mixture was heated at 70 C. for 2 hours. Acetophenone (30 ml.) and an additional portion of acetic anhydride (15 ml.) were then added and the mixture heated at 50 C. for 24 hours. To the cooled mixture ethanol (200 ml.) was added and the mixture was chilled for 3 hours. The product was collected on the filter and washed with ether.

The sulfoacetate was suspended in water (1,000 ml.) and converted to the iodide by stirring with sodium iodide (20 g.) at 60 C. for 1 hour. The product was collected on the filter and washed with water and then ethanol. The crude yield was 22 g. (53 percent). After one recrystallization from ethanol it melted at 220222 C. with decomposition.

The following pyrylium salts were also prepared by the method of above example 1 (characteristics in table 1 A 4,6-Di-(4-chlorophenyl)-2-methylpyrylium iodide B 4,6-Di-(3,4-dichlorophenyl)-2-methylpyrylium iodide EXAMPLE 2--4,6-Dl(4-METHOXYPHENYL)-2- METHYLPYRYLIUM lODlDE (I) Ulla CHaO-Q To a mixture of acetic anhydride (50 ml.) and borontrifluoride ethyl ether (50 ml.), 4-methoxyacetophenone (27 ml.) was added and the mixture heated at 50 C. for 16 hours. The cooled mixture was diluted with ether (200 ml.) and chilled for 2 hours. The product was collected on the filter and washed with ether. The crude yield was 35.6 g. (72 percent).

The fluoborate was suspended in water (1,000 ml.) and converted to the iodide by stirring with sodium iodide (20 g.) at 60 for 1 hour. The product was collected on a filter and washed with water and then alcohol. The crude yield was 33.2 g. Recrystallized from ethanol it melted at 244246 C. with decomposition.

The following pyrylium salts were also prepared by the method of above example 2 (characteristics in table 2).

A 4,6-Di-(2,5-dimethoxyphenyl)-2-methylpyrylium fluoborate B 2-Methyl-4,6-di-2-thienylpyrylium fluoborate TABLE 2 Yield Melting Point C.

EXAMPLE 3-1,4,6-TRl(4-METHOXYPHENYL)2- PlCOLlNlUM IODIDE To a stirred suspension of 4,6-di(4-methoxyphenyl)-2- methylpyrylium iodide (10 g.) in benzene (200 ml.) 4- anisidine g.) was added. The mixture was heated under reflux with a water takeoff for 3 hours. To the cooled mixture ether (400 ml.) was added and the product was collected on the filter and washed with ether. The crude yield was 11.4 g.

(92 percent). Recrystallized from ethanol it melted at 223-4 M 4,6-Di-( 3,4-dichloropheny] l-( 3- dimethylaminopropyl)-2-picolinium iodide Table 3 Crude Melting Point Recrystallization Yield c. Solvent A 96% i46-l47 l86 B 63% 186-489 Ethanol C 76% [84-186 Ethanol D 45% E 98% 243-245 Ethanol F 99% 270-272 Ethanol G 89% l69- l 72 Ethanol H lk 95% 21 1-212 Ethanol J 99% l6l-l63 Ethanol K 89% 233-234 Ethanol L 56% 238-239 Ethanol M 30% l87 l 88 Ethanol EXAMPLE 4-3 '-ETHYL- l ,4,6-TRIPHENYL-2- PYRIDOTHIACYANINE lODIDE CgHs elme CH=C To a solution of l,4,6-triphenyl-2-picolinium iodide (1.12 g.) in pyridine 10 ml.) and acetic anhydride (2 ml.) 3-ethyl-2- ethylthiobenzothiazole ethylsulfate (0.92 g.) was added followed by triethylamine (3 ml.). The mixture was heated under reflux for 5 minutes and the dye thrown out with water (300 ml.), collected on the filter and washed with water. After two recrystallizations from ethanol, the yield of dye was 0.85 g. (51 percent). The orange crystals melted at 28l-283 C.

The following cyanines were also prepared by the method of above example 4 (characteristics in table 4).

A l-(4-Chlorophenyl)-3 -ethyl-4,6-diphenyl-2-pyridothiacyanine iodide 3-Ethyl-l-(2-hydroxyethyl)-4,6-diphenyI-Z-pyridothiacyanine iodide l-( 4-Diethylaminophenyl )-3 -ethyl-4,6-diphenyl-2- pyridothiacyanine iodide l-( 3-Diethylaminopropyl )-3 '-ethyl-4,6-diphenyl-2- pyridothiacyanine iodide 4,6-Di-( 3,4-dichlorophenyl)-3 -ethyll -(4-phenylazophenyl)-2-pyridothiacyanine iodide 1,1-Ethylenebis-(3 -ethyl-4,6-diphenyl-2-pyridothiacyanine iodide) EXAMPLE 52-(4-DIMETHYLAM[NOSTYRYL)- l ,4,6- TRT-(4-METHOXYPHENYL)-PYRlDlNlUM lODlDE To a mixture of l,4,6-tri-(4-methoxyphenyl)-2-picolinium iodide (1.35 g.) and 4-dimethylaminobenzaldehyde (0.41 g.) in ethanol (10 ml.) piperidine (3 ml.) was added and the mixture heated under reflux for 1 hour. The dye was thrown out with water (300 ml.), collected on the filter and washed. After two recrystallizations from ethanol the yield of dye was 0.80 g. (48 percent). The red crystals melted at 2092l 1 C.

The following 4-dimethylaminostyrylpyridinium salts were prepared by the method of example 5 (characteristics in table 5 A 2-(4-Dimethylaminostyryl l -(2-hydroxyethyl )-4,6-

diphenyl-pyridinium iodide 9 B 4,6-Di-(4-chlorophenyl)- l 3-dimethylaminopropyl )-2- (4-dirnethylaminostyryl)pyridinium iodide 1-(4-Chlorophenyl)-2-(4-dimethylaminostyryl)-4,6- diphenyl-pyridinium iodide D 4,6-Di-(3,4-dichlorophenyl)-l-(4-diethylaminophenyl)- 5 2-(4-dimethylaminostyryl)pyridinium iodide E 4,6-Di-(4-chlorophenyl)-2-(4-dimethylaminostyryl)-1-(2 --HYDROXYETl-lYL)pyridinium iodide F 1 ,1 -l-lexamethylene-bis-[2-(4-dimethylaminostyryl)-4,6-

diphenyl pyridinium iodide] G 2-(4-Dimethylaminostyryl l( 2-methyl-6- benzothiazolyl)-4,6-diphenylpyridinium iodide EXAMPLE 6-2-( 3-NlTROSTYRYL)-l ,4,6- TRIPHENYLPYRIDINIUM IODIDE Table 6 Yield Melting Point Recrystallization C. Solvent A 26% 140-141 Ethanol B 16% 298-299 Ethanol C 26% 261-262 Ethanol EXAMPLE 7--1,l,4,4,6,6'-HEXAPHENYL-2,2- PYRlDOCARBOCYANlNE lODlDE Calls (I Julh l u s (Hilly;

To a mixture of 1,4,6-triphenyl-2-picolinium iodide (2.24 g.) and diethoxymethylacetate (3ml.) in dimethylacetamide (10 mls.) diazbieyclooctane (3 g.) was added and the mixture was heated at -l30 for one-half hour. The dye was thrown out with water, collected on the filter and washed. After two recrystallizations from ethanol, the yield of the dye was 0.58 g. (30 percent). The dark brown crystals melted at 283-284 C.

The following symmetrical carbocyanines were prepared by the method of example 7 (characteristics in table 7).

A 1,1 -Di-(4-chlorophenyl)-4,4 '.6,6-tetraphenyl-2.2

pyridocarbocyanine iodide 1,1'Di(4-diethylaminopheny1)-4,4.6.6'-tetruphenyl- 2,2'-pyridocarbocyanine iodide 4,4,6,6'3,4-dichlorophenyl- 1 ,l -di-(4-phcnylazophenyl)-2,2'-pyridocarbocyanine iodide Table 7 Yield Melting Point Recrystallization C. Solvent A 11% 273-275 Ethanol B 13% 300 Ethanol C 7% 22-223 Ethanol EXAMPLE 8--3'-ETHYL-1,4,6-TRI(4- METHOXYPHENYL)-2-PYRlDO-THIACARBOCYANINE IODlDE OOH;

OCH;

To a mixture of 1,4,6-tri-(4-methoxypl1enyl)-2-picolinium iodide, and acetic anhydride (2 ml.) in pyridine (10 ml.) 2-3- acetanilidovinyl-3-ethylbenzothiazolium iodide (1.13 g.) was added followed by triethylamine (3 ml.). The mixture was heated under reflux for 5 minutes. The dye was thrown out with water, collected on the filter and washed. After two recrystallizations the yield of the dye was 0.86 g. (45 percent). The crystals melted at 259260 C.

The following thiacarbocyanines were also prepared by the method of above example 8 (characteristics in table 8).

A 3 -Ethyl-1-(2-hydroxyethyl)-4,6-diphenyl-2- pyridothiacarbocyanine iodide 1-(4-Diethylaminophenyl)-3-ethy1-4,6-diphenyl-2- pyridothiacarbocyanine iodide 1-(2-Diethylaminoethyl)-3'-ethyl-4,6-diphenyl-2- pyridothiacarbocyanine iodide D l-Dimethylamino-3 '-ethyl-4,6-diphenyI-Z-pyridothiacarbocyanine iodide E 1.1 -Ethylenc-bis-( 3 '-ethyl-4,6-diphenyl-2-pyridothiacarbocyanine iodide) F 4,6-Di(3,4-diehlorophenyl)-3-etl1yl-l-(4phcnylazophenyl)-2-pyridothiacarbocyaninc iodide Table 8 Yield Melting Point Recrystallization C. Solvent A 30% 225-226 Ethanol B 50% 265-266 Ethanol C 51% l87-l 88 Ethanol D 8% l74-l75 Ethanol D 25% 252-254 Ethanol F l% 274-275 Ethanol The following oxacarbocyanines were also prepared following the method above of example 8 from the corresponding picolinium salts and Z-B-acetanilidovinyl-3-ethylbenzoxazole iodide (1.09 g.) (characteristics in table 9).

A-l 3-Ethyl-l ',4' ,6'-tri-(4-methoxyphenyl)-oxa-2 pyridocarbocyanine iodide B-l l '-Dimethylamino-3-ethyl-4,6-diphenyl-oxa-2- pyridocarbocyanine iodide C-l l-(4-Diethylaminophenyl)-3-ethyl-4',6'-diphenyl-oxa- 2'-pyridocarboeyanine iodide D-l l S-Dimethylarninopropyl )-3-ethyl-4,6'-diphenyloxa-2-pyridocarbocyanine iodide Table 9 Yield Melting Point Recrystallization C. Solvent A-l 21% 269-270 Ethanol 8-] 3% 188- l 89. Methanol/ethyl acetate C-l 35% 249-250 Ethanol D-l 34% l68-l70 Ethanol The following benzothiacarbocyanines were also prepared following the method of above example 8 from the corresponding picolinium salts and Z-B-anilinovinyl-l-ethyl-B- naphthothiazolium-p-toluenesulfonate (characteristics in table 10).

A-2 l-( Z-Diethylaminoethyl )-3 '-ethyl-4,6-diphenyl-4 ,5

benzo-2-pyridothiacarbocyanine iodide B-2 l-( 4-Diethylaminophenyl )-3 -ethyl-4,6-diphenyl-4,5

benzo-2-pyridocarbocyarline iodide C2 3 '-Ethyll ,4,6-tri-( 4-methoxyphenyl )-4',5 benzo-Z- pyridothiacarbocyanine iodide Table 10 Yield Melting Point Recrystallization C. Solvent A-2 63% l72-l74 Methanol n-z 32% 220-222 Methanol c-z was 245-246 Ethanol EXAMPLE 9--3-ETl-lYL-5- 1 ,4,6-TRl(4- METHOXYPHENOL)-2( 1H )-PYRIDYLIDENE]- ETHYLIDENE}RHODANINE OCH;

l ()Clla To a mixture of 1,4,6-tr;(4-methoxyphenyl)-2-picolinium iodide (1.35 g.) 5-acetanilidomethylene-3-ethylrhodanine D N,N-Ethylene-bis-( 3-ethyl-5-[ (4,6-diphenyl-2( l H pyridyl-idene)ethylidene1rhodanine Table l l Yield Melting Polnt Reerynlullizulion C Solvent A 24% 24% 133-134 Methanol B 22% 277-278 Dimethylucctamide C 15% 208-2) Methanol D 24% l59-l 60 Dimethylacctaminl:

In place of the 5-acetanilidomethylene-3-ethylrhodanine in the above example there may be substituted any other corresponding quaternary salts defined herein by symbol Q to give the corresponding merocyanirle dye compounds having similar photographic utility.

EXAMPLE l0 Anhydro-1,4,6-tris-(4-methoxyphenyl)-3 3-sulfopropyl 2-pyridoselenacarb0cyanine hydroxide.

A mixture of 1,4,6-tris(4-methoxyphenyl)-2-picolinium iodide (1.8 g.), anhydro-Z-B-aeetanilidovinyl-3-(3'-sulfopropyl) benzoselenazolium hydroxide (1.4 g.), acetic anhydride (5 ml.) and triethylamine (8 ml.) in pyridine (10 ml.) was heated under reflux for 5 minutes, allowed to cool and poured over ether (400 ml.) The dye was collected on the filter, washed and recrystallized twice from ethanol. Yield, 36 percent; m.p., 237.9 C.

EXAMPLE 1 l Anhydrol S-diethylaminopropyl)-4,6-bis(4-methoxyphenyl )-3 3-sulfopropyl )-2-pyridothiacarbocyanine hydroxide i s omo g oH=oH-oH=o l a z); N

wzHalz L11 A mixture of l-(3-diethylaminopropyl)-4,6-bis(4-rnethoxyphenyl)-2picolinium iodide (2.7 g.), anhydro-2-B- 'acetanilidovinyl-3( 3sulfopropyl)-benzothiazolium hydroxide (2.1 g.), acetic anhydride (3 ml.) and triethylamine (5 ml.) in pyridine ml.) was heated under reflux for 10 minutes, allowed to cool and poured over ether (400 ml.). The dye was collected by filtration, washed and recrystallized twice from ethanol. Yield, 6 percent; m.p. 220-230 C.

EXAMPLE 12 This example illustrates the increase in sensitivity produced in photographic silver halide emulsions by a number of the preferred dyes used in preparing the emulsions of the invention.

The dyes were tested in a silver bromoiodide emulsion containing 0.77 mole percent iodide of the type described by Trivelli and Smith, Phat. Journal, 79, 330 (1939). The dyes, dissolved in suitable solvents, were added to separate portions of the emulsions at the concentrations indicated. The emulsions were then coated at a coverage of 432 mg. silver/ft. on a cellulose acetate film support. A sample of each coating was exposed on an Eastman IB Sensitometer and to a wedge spectrograph, processed for 3 minutes in a developer of the following composition:

and then fixed, washed and dried. The sensitizing values ob tained are shown in the following table 12.

TABLE 12.--PHOTOGRAPHIO SENSITIZING DATA Dye eon- Sensl- Sensicentratlon tlzing tlzlng (g.) mol. range max. Dye of Ex. N0. silver Emulsion type (mu) (mu) 0. 04 Bromoiodide.... to 570 530 0. 08 d 530 0.07 ......do.. 525 0.08 do- 530 0.08 525 0.08 525 0. 10 575 0.07 575 0.09 580 0. 08 580 0. 10 580 0.07 575 0. 04 580 0. 08 675 0.17 670 0.18 (575 0. 075 0.00 020 0.07 020 0, 05 020 0.07 000 0. 04 625 0.10 630 0. 0s 585 For certain applications in modern color photography, sensitizing maxima in the 595 my. to 615 my. range are required. The dyes of examples 8C, 10 and l l have a sensitizing maxima within the range just mentioned.

In the preparation of the photographic emulsions of the invention, the dyes are advantageously incorporated in the washed, finished silver halide emulsion and should, of course, be uniformly distributed throughout the emulsion. The methods of incorporating dyes in emulsions are relatively simple and well known to those skilled in the art of emulsion making. For example, it is convenient to add the dyes from solutions in appropriate solvents, in which case the solvent selected should be completely free from any deleterious effect on the ultimate light-sensitive materials. Methanol, isopropanol, pyridine, etc., alone or in admixtures, have proven satisfactory as solvents for the majority of the dyes. The type of silver halide emulsions that can be sensitized with the dyes include any of those prepared with hydrophilic colloids that are known to be satisfactory for dispersing silver halides, for example, emulsions comprising natural materials such as gelatin, albumin, agar-agar, gum arabic, alginic acid, etc., and hydrophilic synthetic resins such as polyvinyl alcohol, polyvinyl pyrrolidone, cellulose ethers, partially hydrolyzed cellulose acetate, and the like.

The concentration of the dyes in the emulsion can vary widely, i.e., from about 5 to mg. per liter of flowable emulsion. The specific concentration will vary according to the type of light-sensitive material in the emulsion and according to the effects desired. The suitable and most economical concentration for any given emulsion will be apparent to those skilled in the art upon making the tests and observations customarily used in the art of emulsion making.

To prepare a gelatino-silver halide emulsion with one of my new dyes, the following procedure is satisfactory: A quantity of the dye is dissolved in a suitable solvent and a volume of this solution containing from 5 to 100 mg. of dye is slowly added to about 1,000 cc. of a gelatino-silver halide emulsion. With most of the dyes, 10 to 20 mg. of dye per liter of emulsion sufiice to produce the maximum sensitizing or desensitizing effect with the ordinary gelatino-silver halides including silver chloride, bromide, bromoiodide, chlorobromide, chlorobromoiodide, etc., emulsions. With fine-grain emulsions, which include most of the ordinary employed gelatino-silver chloride emulsions and the like, somewhat larger concentrations of dye may be necessary to secure optimum sensitizing or desensitizing effect. While the preceding has dealt with emulsions comprising gelatin, it will be understood that. these remarks apply generally to any emulsions wherein part or all of the gelatin is substituted by another suitable hydrophilic colloid such as mentioned aboye. One or more dyes can be in the emulsion.

The above statements are only illustrative and are not to be understood as limiting our invention in any sense, as it will be apparent that the dyes can be incorporated by other methods in many of the photographic silver halide emulsions customarily employed in the art. For instance, the dyes can be incorporated by bathing a plate or film upon which an emulsion has been coated, in the solution of the dye in an appropriate solvent. Bathing methods, however, are not to be preferred ordinarily.

Photographic silver halide emulsions such as those listed above, containing the dyes described Hereiricarialso contain such addenda as chemical sensitizers, e.g., sulfur sensitizers, (e.g., allyl thiocarbamide, thiourea, allylisothiocyanate, cystine, etc.), various gold compounds (e.g., potassium chloroaurate, auric trichloride, etc.) (see U.S. Pat. to W. D.

Baldsiefen No. 2,540,085, granted Feb. 6, 1951; R. E. Damschroder No. 2,597,856, granted May 27, 1952, and H.

C. Yutzy et al. No. 2,597,915, granted May 27, 1952), various palladium compounds, such as palladium chloride (W. D. Baldsiefen U.S. Pat. No. 2,540,086, granted Feb. 6, 1951), potassium ehloropalladate (R. E. Stauifer et al. U.S. Pat. No. 2,598,079, granted May 27, 1952), etc., or mixture of such sensitizers; antifoggants, such as ammonium chloroplatinate (A. P. H. Trivelli et a1. U.S. Pat. No. 2,566,245, granted Aug. 28, 1951), ammonium chloroplatinite (A. P. H. Trivelli et al. U.S. Pat No. 2,566,263, granted Aug. 28, 1951), benzotriazole, nitrobenzimidazole, S-nitroindazole, benzidine, mercaptans, etc., (see Mees, "The Theory of the Photographic Process, MacMillan Pub., 1942, page 460), or mixtures thereof; hardeners, such as formaldehyde (A. Miller U.S. Pat. No. 1,763,533, granted June 10, 1930), chrome alum (U.S. Pat. No. 1,763,533), glyoxal (J. Brunken U.S. Pat No. 1,870,354, granted Aug. 9, 1932), dibromacrolein (0. Block et al. British Pat. No. 406,750, accepted Mar. 8, 1934), etc.; color couplers, such as those described in I. F. Salminen et al., U.S. Pat. No. 2,423,730 granted July 7, 1947, Spence and Carroll U.S. Pat. No. 2,640,776, issued June 2, 1953, etc.; or mixtures of such addenda. Dispersing agents for color couplers, such as those set forth in U.S. Patents to E. E. Jelley et al. No. 2,322,027, granted June 15, 1943, and L. D. Mannes et al. No. 2,304,940, granted Dec. 15, 1942, can also be employed in the photographic emulsions of our invention.

We claim:

1. A photographic silver halide emulsion containing 7 a methine dye selected from those represented by the following o m as;

and

wherein R represents a member selected from the group consisting of phenyl, alkylphenyl, alkoxyphenyl, halogen substituted phenyl and nitrophenyl, R, represents a member selected from the group consisting of an alkyl group, allyl, a sulfoalkyl group, a hydroxyalkyl group, an alkoxyalkyl group, a carboxyalkyl group, an alkanoyloxyalkyl group, an alkoxycarbonylalkyl group, an aralkyl group or an aryl group, R represents a member selected from the group consisting of a dialkylamino group and a nitro group, X represents an acid anion, A represents a member selected from the group consisting of a hydroxyalkyl group, a dialkylamino group, a dialsylesi noa kyl group fih group a (B b.

wherein y represents a positive integer of from 1 to 2 and R represents a member selected from the group consisting of a hydrogen atom, an alkyl group, an alkoxy group, a halogen atom, a dialkylamino group, a nitro group, a phenylazo group, an alkylthio group, a 2-methyl-5(or 6)-benzothiazolyl group, a 2-methyl-5(or 6)-benzoxazolyl group and a 2-methyl-5(or 6)- benzimidazolyl group, A represents a member selected from A when n is 1, and a divalent alkylene group when n is 2, Z represents the nonmetallic atoms required to complete a heterocyclic nucleus selected from the group consisting of a thiazole nucleus, a benzothiazole nucleus, a naphthothiazole nucleus, a thionaphtheno-7', 6, 4, S-thiazole nucleus, an exazole nucleus, a benzoxazole nucleus, 3 naphthoxazole slsustasq e e nqls ens e a nt se nucleus a naphthoselenazole nucleus, a thiazoline nucleus, a Z-pyridine nucleus, a 4-pyridine nucleus, a 2-quin0line nucleus, a 4-quinoline nucleus, a 1 -is uinoline nucleus, a 3-iso qu inoline nucleus, a 3,3 -d1alky1ndolenme nucleus, an imidazole nucleus, a benzimidazole nucleus, and a naphthimidazole nucleus, and Q represents the nonmetallic atoms required to complete a heterocyclic nucleus selected from the group consisting of a 2-pyrazolin-5-one nucleus, an isoxazolone nucleus, an oxindole nucleus, a 2,4,6-triketohexahydropyrimidine nucleus, a rhodanine nucleus, a 2(3H)-imidazo[ 1,2- a]pyridone nucleus, a 5,7-dioxo-6,7-dihydro5-thiazolo[3,2-a] pyrimidine nucleus, a 2-thio-2,4-oxazolidinedione nucleus, a thianaphthenone nucleus, a 2-thio-2,5-thiazolidinedione nucleus, a 2,4-thiazolidinedione nucleus, a thiazolidinone nucleus, a 2-thiazolin-4-one nucleus, a 2-imino-4-oxazolidinone nucleus, a 2,4-imidazolidinedione nucleus, a 2- thio-2,4-imidazolidinedione nucleus and a 2-imidazolin-5-one nucleus.

2. A photographic silver halide emulsion in accordance with claim 1 wherein the methine dye has the formula numbered 1.

3. A photographic silver halide emulsion in accordance with claim 1 wherein the methine dye has the formula numbered ll.

4. A photographic silver halide emulsion in accordance with claim 1 wherein the methine dye has the formula numbered 111.

5. A photographic silver halide emulsion in accordance with claim 1 wherein the methine dye has the formula numbered IV.

6. A photographic silver halide emulsion in accordance with claim 1 containing the dye 3-ethyl-1,4,6-triphenyl-2- pyridothiacarbocyanine iodide.

7. A photographic silver halide emulsion in accordance with claim 1 containing the dye 2-(4-dimethylaminostyryl)-l,4,6- tri-(4-methoxyphenyl)pyridinium iodide.

8. A photographic silver halide emulsion in accordance with claim 1 containing the dye 2-(3-nitrostyryl)-l,4,6-triphenylpyridinium iodide.

9. A photographic silver halide emulsion in accordance with claim 1 containing the dye 1,1,4,46,6'-hexaphenyl-2,2'- pyridocarhocyaninc iodide.

10. A photographic silver halide emulsion in accordance with claim 1 containing the dye 3'-ethyl-l,4,6-tri(4-methoxyphenyl)-2-pyridothiacarhocyanine iodide.

11. A photographic silver halide emulsion in accordance 16. A photographic element comprising a support having coated thereon at least one layer containing a photographic silver halide emulsion of claim 2.

17. A photographic element comprising a support having coated thereon at least one layer containing a photographic silver halide emulsion of claim 3.

18. A photographic element comprising a support having coated thereon at least one layer containing a photographic silver halide emulsion of claim 4.

19. A photographic element comprising a support having coated thereon at least one layer containing a photographic silver halide emulsion of claim 5.

Claims

2. A photographic silver halide emulsion in accordance with claim 1 wherein the methine dye has the formula numbered I.
3. A photographic silver halide emulsion in accordance with claim 1 wherein the methine dye has the formula numbered II.
4. A photographic silver halide emulsion in accordance with claim 1 wherein the methine dye has the formula numbered III.
5. A photographic silver halide emulsion in accordance with claim 1 wherein the methine dye has the formula numbered IV.
6. A photographic silver halide emulsion in accordance with claim 1 containing the dye 3''-ethyl-1,4,6-triphenyl-2-pyridothiacarbocyanine iodide.
7. A photographic silver halide emulsion in accordance with claim 1 containing the dye 2-(4-dimethylaminostyryl)-1,4,6-tri-(4-methoxyphenyl)pyridinium iodide.
8. A photographic silver halide emulsion in accordance with claim 1 containing the dye 2-(3-nitrostyryl)-1,4,6-triphenylpyridinium iodide.
9. A photographic silver halide emulsion in accordance with claim 1 containing the dye 1,1'',4,4''6,6''-hexaphenyl-2,2''-pyridocarbocyanine iodide.
10. A photographic silver halide emulsion in accordance with claim 1 containing the dye 3''-ethyl-1,4,6-tri(4-methoxyphenyl)-2-pyridothiacarbocyanine iodide.
11. A photographic silver halide emulsion in accordance with claim 1 containing the dye 1,1-ethylene-bis-(3''-ethyl-4,6-diphenyl-2-pyridothiacarbocyanine iodide).
12. A photographic silver halide emulsion in accordance with claim 1 containing the dye 1-(4-diethylaminophenyl)-3''-ethyl-4,6-diphenyl-4'',5''-benzo-2 -pyridocarbocyanine iodide.
13. A photographic silver halide emulsion in accordance with claim 1 containing the dye 3-ethyl-5- (1,4,6-tri-(4-methoxyphenyl)-2(1H)-pyridylidene)-ethylidine rhodanine.
14. A photographic silver halide emulsion in accordance with claim 1 containing the dye 1,1-hexamethylene-bis-(2-(4-dimethylaminostyryl)-4,6-diphenylpyridinium iodide).
15. A photographic element comprising a support having coated thereon at least one layer containing a photographic silver halide emulsion of claim 1.
16. A photographic element comprising a support having coated thereon at least one layer containing a photographic silver halide emulsion of claim 2.
17. A photographic element comprising a support having coated thereon at least one layer containing a photographic silver halide emulsion of claim 3.
18. A photographic element comprising a support having coated thereon at least one layer containing a photographic silver halide emulsion of claim 4.
19. A photographic element comprising a support having coated thereon at least one layer containing a photographic silver halide emulsion of claim 5.