DE2026750C - Photosensitive photographic silver halide emulsion - Google Patents

Description

35 -R ₁ -N

wherein R _{1 is} an alkylene radical which is bonded to the heterocyclic nitrogen atom of the basic ring, and R ₂ and R _{3 are} each alkyl or aryl radicals or, together with the nitrogen atom on which they are attached, the atoms required to complete a heterocyclic ring.

Particularly advantageous merocyanine dyes have proven to be those in which one of the two rings consists of a rhodanine or 2-thiobarbituric acid ring, each with the carbon atom in the 5-position via a dimethine residue a benzimidazole ring are bonded via the carbon atom in the 2-position of this Ring, where the benzimidazole ring is a tertiary aminoalkyl radical on a heterocyclic nitrogen atom having.

The object of the invention thus proceeds from a photosensitive photographic silver halide emulsion containing a merocyanine dye which spectrally sensitizes the emulsion and is characterized in that the emulsion contains a merocyanine dye of the following structural formula contains:

C = O

where means

R, an alkylene radical with 2 to 6 carbon atoms, R ₂ and R ₃ individually alkyl radicals with 2 to 12 carbon atoms or aryl radicals or together with the nitrogen atom on which they are attached, a heterocyclic radical with 4 or 5 ring atoms,

k = 1 or 2,

η = 1,2, 3 or 4,

Q the atoms required to complete a rhodanine or 2-thiobarbituric acid ring, with the proviso that the ring is bonded to the methine radical via its carbon atom in the 5-position is and

Z to complete a 5- or 6-membered basic heterocyclic ring for merocyanine dyes common type of required atoms.

The basic heterocyclic ring completed by Z can optionally contain a second heteroatom have e.g. B. an oxygen, sulfur, selenium or nitrogen atom.

Photosensitive photographic silver halide emulsions have proven to be particularly advantageous proven according to the invention, which contain a merocyanine dye of the structural formula given, in the Z the to complete a thiazole, oxazole, selenazole, thiazolir, pyridine, quinoline, 3,3-dialkylindolenine or imidazole ring required Represents atoms.

In detail, Z can thus stand for the atoms that complete

a thiazole ring, e.g. B. a thiazole, 4-methylthiazole, 4 - phenylthiazole, 4 - methylthiazole, 5-phenylthiazole, 4,5-dimethylthiazole. 4,5-diphenylthiazole, 4- (2-thienyl) thiazole, benzothiazole 4-chlorobenzothiazole, 5-chlorobenzothiazole, 6-chlorobenzothiazole, 7-chlorobenzothiazole, 4-methylbenzothiazole, 5-methylbenzothiazole, 6-methylbenzothiazole, 5-bromobenzothiazole, 6-bromobenzothiazole, 5-phenylbenzothiazole, 4-methoxybenzothiazole, 5-methoxybenzothiazole, 6-methoxybenzothiazole, 5-iodobenzothiazole, 6-iodobenzothiazole, 4-ethoxybenzothiazole, 5-ethoxybenzothiazole, tetrahydrobenzothiazole, 5,6 - dimethoxybenzothiazole, 5,6-dioxymethylene benzothiazole, 5-hydroxybenzothiazole, 6 - hydroxybenzothiazole, naphtho [2, l-d] thiazole, naphtho [l, 2-d] thiazole, 5 - methoxynaphtho [2,3 - d] thiazole, 5 - ethoxynaphtho [1,2 - d] thiazole, 8 - methoxynaphtho- [1,2 - d] thiazole, 7 - methoxynaphtho [1,2 - d] thiazole or 4'-methoxythianaphtheno-7 ', 6', 4, 5-thia / ol ring;

a cxazole ring, e.g. B. a 4-methyloxazole, 5-methyloxazole, 4-phenyloxazole, 4,5-diphenyloxazole, 4-Ethyloxazole-, 4,5-Dimethyioxazole-, 5-phenyloxazole, benzoxazole, 5-chlorobenzoxazole, 5-methylbenzoxazole, 5-phenylbenzoxazole, 6-methylbenzoxazole, 5,6-dimethylbenzoxazole, 4,6-dimethylbenzoxazole, 5-methoxybenzoxazole, 5-ethoxybenzoxazole, 5-chlorobenzoxazole, 6-methoxybenzoxazole, 5-hydroxybenzoxazole, 6-hydroxybenzoxazole, naphtho- [2, l-d] oxazole or naphtho [1,2-d] oxazole ring;

a selenazole ring, e.g. B. a 4-Methylselcnazol-, 4-phenylselenazole, benzoselenazole, 5-chlorobenzoselenazole, 5-methoxybenzoselenazole, 5-hydroxybenzoselenazole, tetrahydrobenzoselenazole, Naphtho [2, l-d] selenazole or naphtho [1,2-d] selenazole ring;

a thiazoline ring. z. B. a thiazoline or 4-methylthiazoline ring,

a pyridine ring, e.g. B. a 2-pyridine, 5-methyl

2-pyridine, 4-pyridine or 3-methyl-4-pyridine ring;

a quinoline ring, e.g. B. a 2-quinoline, 3-methyl-2-quinoline. 5-ethyl-2-quino'in-. 6-chloro-2-quinoline-, 8-chloro-2-quinoline, 6-methoxy-2-quinoline, 8-ethoxy-2-quinoline, 8-hydroxy-2-quinoline, 4-quinoline-, o-methoxy ^ -quinoline-. 7-methyl-4-quinoline, S-chloro ^ quinoline, 1-isoquinoline, 3,4-dihydro-1-isoquinoline or 3-isoquinoline ring;

a 3,3-dialkylindolenin ring, e.g. B. a 3,3-dimethylindolenine or 3,3,5-trimethylindolenine ring or

an imidazole ring, e.g. B. an imidazole, 1-alkylimidazole, 1-alkyl-4-phenylimidazole. 1-alkyl-4,5-dimethylime ^; '.Azol- ^l, benzimidazole, 1-alkylbenzimidazole, 1 -AryI-5,6-dichlorbenzimidazol-. 1-alkyl-1 H-naphtho [1,2-d] imidazole-, 1-aryl-3 H-naphtho [1,2-d] imidazole- or a 1-alkyl-5-methoxy-1 H-naphtho [ 1,2-d] imidazole ring.

In the structural formula I given, R ₁ can be, for example, ethylene, n-propylene, isopropylene. n-butylene, iso-butylene. n-pentyien-. Be 2-ethylpropylene, n-hexylene or a 2-ÄthylbutyIenrest. _{R 1} is preferably an alkylene radical having 1 to 4 carbon atoms.

R ₂ and R _{3 have} the meaning of alkylresienes. for example, these can consist of ethyl, n-propyl, isopropyl, η-butyl, iso-butyl, n-pentyl, n-hexyl, 3-ethylbutyl, n-octyl, n-dodecylbenzyl - or phenylethyl radicals. Preferably, R ₂ and R ₃ are alkyl radicals having 1 to 4 carbon atoms. If R ₂ and R ₃ are aryl radicals, these are preferably radicals of the phenyl or naphthyl series, ie, R ₂ and R ₃ can be, for example, phenyl, tolyl, naphthyl, methoxyphenyl or chlorophenyl radicals. If R ₂ and R ₃ together with the nitrogen atom on which they are located form a heterocyclic radical, this preferably consists of a morpholine, thiomorpholine, piperidine, pyrrolidine, 4-alkylpiperazine, e.g. B. 4-methylpiperazine, decahydroquinoline or tetrahydroquinoline ring.

The ring represented by Q consists preferably of a 3-alkylrhodanine or a 1,3-dialkylthiobarbituric acid ring, the alkyl radicals of these rings preferably having 1 to 4 carbon atoms and for example consist of methyl, ethyl, propyl or butyl radicals.

Such light-sensitive photographic silver halide emulsions have proven to be particularly advantageous proved to be a merocyanine dye de. given structural formula, in which Q has the meaning given and otherwise means

η = 2,

k = 1,

Z which is used to complete a benzimidazole

ringes required atoms,
R _{1 is} an alkylene radical having 2 to 3 carbon atoms and

R ₂ and R ₃ each represent an alkyl radical having 1 to 4 carbon atoms.

Emulsions with such microcyanine dyes have proven to be particularly advantageous whose benzimidazole ring from a 5-chloro or consists of a 5,6-dichlorobenzimidazole ring.

The invention provides light-sensitive photographic silver halide emulsions which which not only have favorable solubility properties, excellent incubation stability at high temperatures and high humidity as well also have excellent spectral sensitivity, but rather also excellent Show sensitivity to the blue portion of the spectrum.

Typical of these cyanine dyes which can be used in the preparation of useful photographic silver halide emulsions according to the invention are:

3-ethyl-5 -! [! - ethyl-3- (2-morpholinoethyl) -

2-benzimidazolinylidene] ethylidene] rhodanine; 3-ethyl-5-! Tl-ethyl-5-methyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene-

rhodanine;
5 -! [5-Chloro-1-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene | -3-ethyl-

rhodanine:
5-! T5.6-dichloro-1-ethyl-3- (2-pipcridinoiithyl) -2-benzimidazolinylidene] ethylidene) -3-ethyl-

rhodanine;
5 - ([5.6-DiChIOrO-I -ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene} -3-ethyl-

niiiüaiiiii,
5-! 4- [5.6-dichloro-1-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] -2-butenylidene} -

3-ethylrhodanine;
5-f [5.6-dichloro-1-αΐ1ψΙ-3- (2-πιοφηο1ΐηο3ΐΙψΙ) -2-benzimidazolinylidene] ethylidene} -l.3-diethyl-

2-thiobarbituric acid;
5 - [{5.6-dichloro-l-ethyl-3- [2- (l-pyrrolidinyl) ethyl] -2-benzimidazolinylidene} ethylidene] -

3-ethylrhodanine;
5- [! 5.6-dichloro-1-ethy 1-3-f 2- (3-pyrrolin-1 -yl) -ethyl] -2-benzimidazoiinyliden} ethylidene] -

3-ethylrhodanine;
5-! [5.6-dichloro l- (2-dimethylaminoethyl) -3-ethyl-2-benzimidazolinylidene] ethylidene} -

3-ethylrhodanine;
5-i [5,6-dichloro-l- (2-diethylaminoethyl) -3-ethyl-2-benzimidazolinylidene] ethylidene} -

3-ethylrhodanine;
5-i [5.6-dichloro- 1 - (2-diethylaminoethy I) -3-ethyl-2-benzimidazolinylidene] ethylidene h

1,3-diethyl-2-thiobarbituric acid; 5 - {[5.f "dichloro-1- (3-dimethylaininopropyl) - 3-ethyl-2-benzimidazolinylidene] ethyIids! -

3-ethy! Rhodanine; 5- {[5.6-dichloro-1 - [(2-dimethylamino-1-methyl> äÜiyl] -3-ethy1-2-benzimidazolinyiiden] ethy1-

iden l-3-ethylrhodanine; 5- {6- [5,6-DichloTO-1-ethyl-3- (2-raofpholino ethyD-2-benziinida2olinyIiden] -2,4-hexatriene} - 3-äthylrhodanm;

5Οί1! 1

5.) 4- [3- [2- (| -Pyrrolinyl) butyl] -2-benzothiazole-

ynylidcn! -2-butenylideni-3-propylrhodanine;
5-! | 3- [2- (4-methyl-l-pyrazinyl) ethyl] -2-bcnzo-

sclnazolinylidcn] iilhylidcnj-1,3-diethyl-2-thiobarbituric acid;

5- | 6-! 3- [2- [2- (l-dccahydroquinolyl) ethyl] -

2-benzoxazolinylidene} -2,4-hexadicnylidene! -

1,3-diethyl-2-thiobarbituric acid;
3-ethyl-5 - !! l-ethyl-3- [4- (l-tetrahydroquinolyl) butyl] -2-benzimidazolinylidene} ethylidene} -

rhodanine.

The dyes used according to the invention can be prepared by converting a heterocyclic one quaternary ammonium salt whose heterocyclic nitrogen atom with a tertiary Aminoalkylsalzrest is substituted with an acidic intermediate compound of the type as it is usually is used for the production of Mcrocyaninfarerstoffcn. The implementation is in the presence of a basic Kondcnsationsmittcls carried out, z. B. in the presence of a trialkylamine, e.g. B. in the presence of triethylamine or tributylamine or one Dialkyl aniline, e.g. B. N.N-dimethylaniline or one heterocyclic tertiary amine, ζ. B. pyridine or N-Ätä /! Piperidine. The condensation can take place in advantageously carried out in a suitable diluent, e.g. B. methanol, dimethylformamide or 5,4-dioxane. The reaction is preferably carried out under reflux conditions, in which Trap takes about 5 to 20 minutes to expire.

Dyestuffs of the formula I given, in which η = I. can be easily prepared by condensing a compound of the following formula:

Il

wherein R ₁ . R ₂ . R ₁ . Ic and Z have the meanings already given, with a compound of the following structural formula:

III.

H ₂ -C-

'Q,

-C = O

where Q has the meaning already given, in the presence of a basic condensing agent. Dyes of the formula I in which π = 2, 3 or 4, can be easily prepared by condensing a compound of the following formula:

Z--

2-benzimidazolinylidene] -3-ethylrhodanine; 5- {4- [5,6-DichloiO-1 -3 & 7ΐ-3- (2-ΰίϊοπιοφΙιθΗ "ηο- ethyl> -2 benzimidazolinylidene] -2-butenylidene} -

3- ethylrhodanine; 5 - {[5.6-dichloro-1-ethyl-3- (2-piperidinoethyl} - 2-benzimidazolinylidene] ethylidene} -13-diethyl.2 -thiobarbituric acid;

IV. NR ₁ -N = (CH-CH) = T = C-CH ₃

wherein R ₁ . R ₂ , R ₃ . k and Z have the meaning already given, with a combination of the following

Structural formula:

Marg

V. R ₁₂ -N- (CII = Cl Ι) -, - (] I- C

C = O

where means

R _{n is} a hydrogen atom or an acetyl radical, R _{12 is} a phenyl radical and
ρ - 2, 3 or 4.

The intermediate compounds of formulas II and IV can be prepared from heterocyclic ammonium bases of the type commonly used for preparation by McrocyaninfarbslolTcn is used by reaction with an alkylating agent of the following structural formula:

NR ₁ -Cl • HCl

in which R ₁ , R 2 and R _{3 have} the meanings already given.

In the preparation of negative silver halide emulsions Preferably, the dyes are added to the washed, finished silver halide emulsion incorporated, in which they are uniformly distributed in the usual manner. Procedure for Incorporation of sensitizing dyes in silver halide photographic emulsions are well known. It has proven expedient to use the dyes in the form of solutions in suitable solvents incorporated into the emulsions, for example using methanol, isopropanol, pyridine or water or mixtures thereof as a solvent.

The new merocyanine dyes are eminently suitable for sensitizing the customary known silver halide emulsions which are prepared in a known manner using hydrophilic colloids, for example using naturally occurring hydrophilic colloids, e.g. B. gelatin, albumin, agar-agar, gum arabic, alginic acid and the like and / or hydrophilic synthetic polymers such as polyvinyl alcohol, polyvinylpyrrolidone, cellulose ether, partially hydrolyzed cellulose acetate and the like.

If necessary, polymerized vinyl compounds, such as those from U.S. Patents 3,142,568, 3,193,386, 3,062,674 and 3,220,844, can also be used to prepare the emulsions in the customary manner are known, are used, i.e. for example in water-insoluble polymers of alkyl acrylates and Alkyl methacrylates, acrylic acid, sulfoalkyl acrylates or sulfo-alkyl methacrylates and the like.

The silver halide of the silver halide emulsions. can be made from one of the usual photosensitive Silver salts exist, e.g. B. silver chloride, silver bromide, Silver iodide, silver chlorobromide, silver bromoiodide, Silver Morobromoiodide and the like

The concentration of merocyanine dyes in the emulsions can vary widely . Expediently, concentrations of about 1/2 to about 100 mg per liter of flowable emulsion are used. The most favorable concentration in each individual case depends on the type of light-sensitive emulsion and the specifically desired effects. The most favorable concentration in the individual case can easily be determined by a series of tests.

A light-sensitive gelatin-silver halide photographic emulsion according to the invention can be prepared, for example, as follows:
First, a certain amount of the merocyanine dye is dissolved in a suitable solvent, after which a certain amount of the resulting solution containing 5 to 100 mg of dye is slowly added to about 1 liter of the gelatin-silver halide emulsion.

With most of the dyes which can be used according to the invention, maximum sensitization effects can be achieved common gelatin-silver bromide emulsions including gelatin-silver bromoiodide emulsions and gelatin silver chlorobromide emulsions at concentrations of from about 5 to about 20 mg of dye per Liters of emulsion.

In the case of fine-grain emulsions, to which most of the usual Gclatine silver chloride emulsions belong, slightly higher concentrations of the dye may be necessary to achieve optimal sensitization effects. The same applies to those emulsions which contain another binder instead of gelatin or whose gelatin is partially replaced by another binder .

Finally, it is also possible to use the merocyanine dyes by bathing a photographic plate or film in a solution one or more of the dyes in a suitable solvent into the emulsion layer or layers to incorporate the plates or films

I. Preparation of merocyanine dyes

1. 3-Ethyl "5 - {[1-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene} rhodamine

C ₂ H ₅

N CO NC ₂ H ₅

\ Il

C = CH-CH = C CS

N S

I CH ₂ CHj

CH ₁ CHjN O

CH ₂ CHj

A mixture of 1.7 g of 1-ethyl-2-methyl-3- (2-mor pholinoäthyObenamida / oliumchloridhydrochlorid 1.6 g S-Acetatiflidomethylen ^ -äthylrhodanin, 10 m Pyridine and 1.2 g of tetramethylgnanidine were heated to the recycle temperature for 20 Mt.

the reaction mixture was allowed to cool extracted with 200 ml portions of ether, whereupon the extracts were combined and evaporated to dryness the. The solid skirts were then with what " added, which was filtered. The backwater

In 6s, two-wheelers were recrystallized by ethanol. It was a total of 0.3 g ('.3%) of pure dye in the form of reddish crystals with a dot of 16 to 169 ° C (dec.).

2. 3-Ethyl-5-i [l-ethyl-5-methyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene} rhodanine

CO NC ₂ H ₅

= CH-CH = C

CS

CH ₂ CH ₂

CH, CH, N

I.
\

CH ₂ CH ₂

A mixture of 1.8 g of l-ethyl ^ .S-dimethyl-S - ^ - morpholinoäthynbenzimidazoliumchloridhydrochlorid, 1.6 g of S-acctanilidomethylene-B-ethylrhodanine. 10 ml of pyridine and 1.2 g of tetramethylguanidine were added Heated to reflux temperature for 20 minutes. After cooling, the reaction mixture became extracted with four 250 ml portions of ether, whereupon the ether extracts combined and the ether evaporated became. The residue was taken up with a small amount of ethanol and kept in the cold. The firm ones Portions were filtered off, washed with ethanol and recrystallized twice from ethanol. There were 0.25 g of pure dye, corresponding to 11% of theory, in the form of red crystals with a melting point obtained from 190 to 191 ° C (dec.).

3. 5- | [5-chloro-1-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene} -3-ethylrhodanine

A mixture of 1.9 g of 5-chloro-1-ethyl-2-methyl-3- (2-morpholinoethyl) benzimidazolium chloride hydrochloride, 1.6 g of S-acetanilidomethylene-ethylrhodanine, 10 ml of pyridine and 1.2 g of tetramethylene guanidine was 20 minutes heated to reflux temperature for a long time. After cooling, water was added to the reaction mixture. The mixture was then placed in the cold, whereupon the deposited precipitate was filtered off, washed with water and recrystallized twice from methanol. The crude dye thus obtained was then extracted six times with 100 ml portions of ether. A total of 0.25 g of pure dye, corresponding to 10% of theory, was obtained in the form of shiny purple-colored crystals with a melting point of 202 to 204 ^° C. (dec.).

4. 5- {[5,6-Dichloro-1-ethyl-3- (2-piperidinoethyl) -2-ben? 'Midazoinylidene] ethylidene-3-ethylrhodanine

C ₂ H ₅

Cl

N S

CH ₂ CH ₂

CH ₂ CH ₂ N CH ₂

CH ₂ CH ₂

A mixture of 2 g of 5,6-dichloro-1-ethyl-2-methyl-3 - (2-piperidinoethyl) benzimidazolium chloride hydrochloride, 1.6 g of 5-acetanilidomethylene-3-ethylrhodanine, 15 ml of dimethylacetamide and Ig triethylamine was taken for 2 minutes heated to a temperature of 120 to 130 ⁰ C. After cooling, water was added to the reaction mixture, whereupon the water was decanted off from the oily layer formed. The oily layer was then stirred with a small amount of ethanol. After cooling, the deposited precipitate was filtered off, dissolved in pyridine and precipitated from ethanol. 0.6 g of pure dye corresponding to 23% of theory was obtained in the form of red crystals with a golden sheen and a melting point of 278 to 280 ^° C. (dec.).

Analysis door C ₂₃ H ₂₈ Ci ₂ N ₄ OS ₂ :

Calculated ... C 54.0, H 5.5, N 11.0;
found .... C 53.7, H 5.3, N 10.7.

5. 5 - {[5,6-dichloro-1-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene} -3-ethylrhodanine

A mixture of 2.1 g of 5,6-dichloro-1-ethyl-2 - methyl - 3 - (2 - morpholinoäthy]) benzimidazolium chloride hydrochloride, 1.6 g of 5-acetanilidomethyl-3-ethylrhodanine, 10 ml of pyridine and 1.2 g of tetramethylguanidine was refluxed for 10 minutes. After cooling, the reaction mixture became diluted with 20 ml of water and the mixture was chilled. The unusual one Precipitate was filtered off, washed with water and dissolved in pyridine. From the pyridine solution the dye was then precipitated by adding ethanol. There was a total of 0.8 g of dye, accordingly 31% of theory, in the form of red crystals with a melting point of 195 to 197 "C (dec) obtained.

6. 5- {4- [5,6-Dichloro-1-ethyl-3- (2-moφholinrathyl) -2-benzimidazoIinylidene] -2-butenylidene} -3-ethylrhodanine

C ₂ H ₅
Ο N CO NC ₂ H ₅

W \ I I

T | T C = CH-CH = CH-CH = C CS

Ο Ν CH ₂ CH ₂ S

CH ₂ CH ₂ NO

CH ₂ CH ₂

A mixture of 2.1 g of 5,6-dichloro-1-ethyl

2 - methyl - 3 - (2 - morpholinoäthy!) Benzimidazolium chloride hydrochloride, 1.7 g of 5-acetnilidoallylidene-3-ethylrhodanine, 10 ml of pyridine and 1.2 g of tetramethyl-5-guanidine was heated to reflux temperature for 15 minutes. After cooling, the reaction mixture became mixed with ether, whereupon the ethereal layer is decanted from the oily layer would. The oily layer was washed first with ether and then with water and then in Dissolved ethanol. After cooling, the deposited precipitate was filtered off with ethanol washed and dissolved in pyridine. The resulting dye was precipitated by adding ether. There was a total of 1.1 g of pure dye corresponding to 40% of theory in the form of dark blue Crystals with a melting point of 251 to 252 ° C (dec.) Are obtained.

In a corresponding manner, by replacing the 5-acetanilidoallylidene-3-äthylrhodanins by a corresponding amount of S-acetanilido ^^ - pentadienylidene the dye 5 - {6 - [5,6 - dichloro - 1 - ethyl-

3 - (2 - morpholinoäthyi) - 2 - benzimidazolinylidene] -2,4-hexadienylidene} -3-ethylrhodanine manufactured.

Similarly, by replacing the benzimidazolium salt used in this example by 5,6 - dichloro - 1 - ethyl - 2 - methylthio-3- (2-morpholinoethyl) benzimidazolium chloride hydro- chloride of the dye 5 - [5,6 - dichloro - 1 - ethyl-3 - (2 - morpholinoäthyi) - 2 - benzimidazolinylidene] -3-ethylrhodanine manufactured.

8. S-CiS.ö-Dichloro-l-üthyl-S-Cl-il-pyrrolidiny ^1. ) - ethyl] -2-benzimidazolinylidene} ethylidene] -

3-ethylrhodanine

A mixture of 2 ^ 5,6-dichloro-1-ethyl-2 - methyl - 3 - [2 - (I - pyrrolidinyl) ethy!] benzimidazo · - lium chloride hydrochloride, igS-Acclanilidomethylcn-3-äthylrhodanin, 10 ml pyridine and 1.2 g tetramethylguanidine was refluxed for 15 minutes. After cooling, the reaction mixture became mixed with water, stirred and refrigerated. The deposited solid precipitate was filtered off, washed with water and dissolved in pyridine. The dye was made from the pyridine solution with ethanol failed. There were a total of 1.2 g of pure dye corresponding to 48% of theory in the form of red needles with a greenish tinge and a melting point of 151 to 152 "C (dec.).

9. 5- [15,6-dichloro-1-ethyl-3- [2- (3-pyrrolin-1-yl) -alhy!] -2-benzimidazolinylidene} ethyiides] -3-ethylrhodanine

7. 5-i [5,6-dichloro-1-ethyl-3- (2-morpholinoethyl) -

2-benzimidazolinylidene] ethylidene} -1,3-diethyl-

2-thiobarbituric acid

CO-N

C = CH-CH = C

CS

CO-N

CH ₂ CH,

CH ₂ CH ₂

Ct 1
2 5

CH ₂ CH ₂

A mixture of 2.1 g of 5,6-dichloro-1-ethyl-2 - methyl - 3 - (2 - moTpholmoäthyObenamidazoriurnchloridhydrochlorid, 1.6 g 5 - Acetanilidomethylenl _v 3-diethyl-2-tMob £ rWtursäure, 10 ml pyridine, 0.5 g of acetic anhydride and 1.8 g of tetraethylguanidine were heated to reflux temperature for 10 minutes. After cooling, the reaction mixture was diluted with 30 ml of water, whereupon the mixture was cooled. The precipitate which had separated out was filtered off, washed with water and recrystallized from ethanol The recrystallized dye was then redissolved in ethanol, whereupon reddish crystals separated out on cooling to room temperature, which were filtered off and recrystallized again from ethanol yellow crystals with a melting point v-: 47 to 248 ° C (dec.).

2.6 g of 5,6-dichloro-1-ethyl-2-methyl-3- [2- (3-pyrrolin-1 -yO-ethyrbenzimidazolium perchlorate hydro-

perchlorate, 1.5 g of 5 - acetanilidomethylene - 3 - ethylrhodanine and 1.2 g of 1,1,3,3-te'ramethylguanidine dissolved in 15 ml of Ν, Ν-dimethylacetamide, whereupon the solution was heated to gentle reflux under reflux for 5 minutes. After cooling down the reaction mixture was diluted with 300 ml of water, whereupon the walls of the vessel were used Formation of crystals scratched. The deposited precipitate was filtered off and dissolved in 50 ml Methanol boiled. After cooling, the precipitated crude dye was filtered off and taken out of one Recrystallized pyridine-methanol mixture. A total of 0.6 g of pure dye, corresponding to 24 ° / of theory with a melting point of 187 to 188 C (dec.).

10. 5 - {[5,6-dichloro-1- {2-dimethylaminoethyl) -3-ethyl-2-benzimidazounylidene] ethylidene} -3-ethylrliot'anine

A mixture of 1.9 g of 5,6-dichloro-1- (2-di methylaminoethyl) - 1 - ethyl - 2 - methylbenzimidazG lium hydrochloride, 1.6 g of 5 - acetanilidomethylene

3-äthylrhodanin, 10 ml of pyridine and 1 g of triethylami were heated to reflux temperature for 30 minutes. The reaction mixture was then poured into 150N water, whereupon the X.

separated, washed with water and with ethane has been recorded. After cooling, the precipitate which had separated out was filtered off with ethane

washed and dissolved in pyridine. The dye was precipitated from the solution with methanol. It a total of 0.2 g of dye corresponding to 8 "v> of theory in the form of red crystals with a melting point .on 291 to 293 C (dec.).

11. 5 -; [5.6-dichloro-1- (2-diethylaminoutyl) -

3-ethyl-2-benzimidazolinylidene] iithylidene; -

3-ethylrhodanine

CH,

co

'= CH - CH - = C

■ NC ₂ H, - CS

CH ₂ CH ₂ N-ICH,), rhodanine. 10 ml of dimethyl acetamide and 1 g of triethylamine were heated for 10 minutes to a temperature of 160 to 180 ° C. with stirring. The reaction mixture was then diluted by adding 100 ml of water. The precipitate which had separated out was filtered off, washed with water and taken up with ethanol After cooling, the precipitated solid dye was filtered off, dissolved in pyridine and precipitated from the pyridine solution by adding ethanol. 0.1 g of pure dye corresponding to 9% of theory was obtained in the form of red crystals with a melting point of 2R ^ to 289-C (dec .) receive.

14. 5-; L5,6-dichloro-l - [(2-dimchylamino-

l-mcthyi) ethyl] -3-ethyl-2-be.izimidazolinyliden] -

äthviidenl-3-äthvlrhodanin

A mixture of 4 g of So-dichloro-lQ-diethylaminoethyl) -3-ethyl-2-methylbenzimidazolium chloride hydrochloride, 3.2 g of 5-acetanilidomethylene-3-iithylrhodanine, 20 ml of pyridine and 2 g of triethylamine was refluxed for 15 minutes . After cooling, the precipitated crude dye was filtered off, washed first with ethanol and then with water and then dissolved in pyridine. The dye was precipitated from the solution by adding methanol. There were a total of 2.9 g pure _J0 dye obtained according to 58% of theory in the form of red crystals having a melting point 184-185 C (dec.).

Analysis for C ₂₁ H ₂₈ Cl ₂ N ₄ OS ₂ :

Calculated ... C 52.9, H 5.7:

found .... C, 53.1. H 5.9.

12. 5-l [5.6-dichloro-1- (2-diethylaminoethyl) -3-ä'.hyl-2-benzimidazolinylidene] ethylidene} -1,3-diethyl

2-thiobarbituric acid

A mixture of 2 g of 5,6-dichloro-l- (2-diethylaminoethyl) - 3 - ethyl - 2 - methylbenzimidazclium chloride hydrochloride, 1.5 g of 5-anilinomethylene-l, 3-diethyl-2-thiobarbituric acid, 10 ml of pyridine, 2 g of triethylamine and 0.5 g of acetic anhydride was 30 minutes long heated to reflux temperature. The reaction mixture was then chilled and filtered would. The filtrate was then treated with water, whereupon the aqueous layer of the oily layer formed Layer was decanted. The oily layer was washed with water and then in Benzo! solved. The benzene solution was then separated from a small amount of water and made up to 10 ml constricted. 10 ml of ligroin were added to the concentrate obtained. After cooling, the precipitated dye is filtered off, washed with ligroin and recrystallized from benzene and ligroin. There was a total of 0.1 g of dye corresponding to 3% of theory in the form of brown crystals with a Melting point of 183 to 185 "C obtained.

13. 5 - {[5,6-dichloro-1- (3-dimethylaminopropyl) -

3-ethyl-2-benzimidazolinylidene] ethylidene | -

3-ethylrhodanine

A mixture of 1.9 g of 5,6-dichloro-1- (3-dimethylaminopropyl) -1-ethyl-2-methylbenzimidazolium chloride hydrochloride, 1.6 g acetanilidomethyl-3-ethyl-C ₂ H ₅

ι
N

CO N-CH,

= CH-CH = C

CS

N S

CH ₃ -C-CH ₂ -N (CHj) ₂

A mixture of 1.9 g of 6-dichloro-1 - [(2-dimethylamino -1-methyljäthyl] -3-ethyl-2-methylbenzimidazolium chloride hydrochloride. 1.6 g of 5-acetanilidomethylene-3-ethylrhodanine, 10 ml of pyridine and Ig triethylamine was 2 ' / heated for ₂ hours at reflux temperature. After cooling, the reaction mixture this was mixed with ether, whereupon the ether layer was decanted from the resulting oily layer. the oily layer was washed with ether and stirred with a small amount of ethanol. the mixture was then Quenched, whereupon the precipitated crude dye was filtered off, washed with ethanol and dissolved in pyridine. The dye was then precipitated from the pyridine solution by adding methanol. 0.1 g of dye corresponding to 4% of theory was in the form of red crystals with a Melting point of 298 to 299 ° C (dec.).

The procedures described in Examples I to 14 were repeated, but this time on Instead of the benzimidazolium salts used in Examples 1 to 14 were used:

! - / i-Diethylaminouthyllepidiniurnjodidhydro-

iodide;
3- / f-diethylaminoethyl-2-methylbenzo-

thiazolium iodide hydroiodide; 3-diethylaminoethyl-2-methylbenzoxazolium-

iodide hydroiodide;
3 -, -; - Diethylaminoethyl-2-methylbenzosclcn-

azolium iodide hydroiodide and l- / i'-diethylaminoethyl-2,3,3-trimethylindolium iodide hydroiodide.

II. Making the connections

A.! - / i-Diethylaminoethyllepidinium iodide hydroiodide

CH ₃

CH ₂ CH ₂ N- (C ₂ H ₅ J ₂ ■ HJ

C-CH,

CH ₂ CH ₂ N- (C ₂ H ₅ J ₂ • HJ

A mixture of 44.7 g of 2-methylbenzothiazole, 34.4 g / J-Diäthylaminoäthylchloridhydrochlorid and 33.2 g of powdered potassium iodide was heated for 24 hours to a temperature of 135-140 ⁰ C. The cooled reaction mixture was then extracted with ethanol and the extract was filtered. Ether was added to the filtrate, whereupon the separated oil was washed several times with ether. The compound obtained was not obtained in crystalline form, but was further processed in the manner incurred.

C. 1-Ethyl-2-methyl-3- (2-morpholinoethyl) -benzimidazolium chloride hydrochloride

35

40

45

55

CH ₃

CH ₂ CH ₂ N

CH ₂ CH ₂

O · HCl

/
CH ₂ CH ₂

A mixture of 16 g of 1-ethyl-2-methylbenzene-iidazole and lS.ogN - ^ - Chloroäthylmorpholinhydrochlo-

A mixture of 42.3 ^ lepidine. 34.4 g / i-diethylaminoethyl chloride hydrochloride and 33.2 g of powdered potassium iodide was heated at a temperature of 135 to 140 ° C for 2 hours. The frightened one Melt was washed di-iin with ether and then extracted with 300 ml of ethanol. The extract obtained was filtered, followed by the filtrate ether was added. The ether-alcohol mixture then became semi-solid from the formed The residue is decanted off, whereupon this residue is washed several times with ether and then filtered would. A total of 48 g of a solid hygroscopic mass were obtained after drying for 2 weeks obtained in a vacuum desiccator over calcium chloride.

B. S-zf-diethylaminoethyl ^ -methylbenzothiazolium iodide hydroiodide

rid was heated to 180 to 19 <VC for 1 hour. The mixture was then melted together. A cake was formed as it cooled off, which in one Mortar was pounded. The crushed solid mass was then suspended in acetone. After 2 hours The mass was filtered off, washed with acetone and dried in a vacuum desiccator. The yield of reaction product was 2.7.3 g, corresponding to 78% of theory. The connection was obtained in the form of a colorless, solid hygroscopic mass.

D. 1-Ethyl-2,5-dimethyl-3- (2-morpholinoethyl) -benzimidazolium chloride hydrochloride

C-CH ₃

CH, N

Cl "

CH ₂ CH ₂

CH ₂ CH ₂ N

O ■ HCl

CH ₂ CH ₂

A mixture of 17.4 g of 1-ethyl-2,5-dimethylbenzimidazole and 18.6 g of N-2-chloroethylmorpholine hydrochloride was heated to a temperature of 180 ° C for 1 hour. The mixture was melted together and let cool into a cake. The cooled cake was then washed with 300 ml of acetone Heated to the boil for 7 hours. In this way a crystalline mass was obtained which was filtered off and washed with acetone. The precipitate was then dried in a vacuum desiccator. The yield of the reaction product obtained in the form of a colorless hygroscopic crystalline mass was 21: g, corresponding to 58% of theory.

E. 5-Chloro-1-ethyl-2-methyl-3- (2-morpholinoethyl) benzimidazolium chloride hydrochloride

C ₂ H,

C-CH ₃

CH ₂ CH ₂

CH ₂ CH ₂ N

O · HCl

CH ₂ CH ₂

A mixture of 19.5 g of 5-chloro-1-ethyl-2-methyl-benzine) idazole and 18.6 g of N-chloroethylmorpholine hydrochloride was heated to 180 ° C. for 1 hour. The mixture melted together and formed a glass-like mass on cooling. It was pounded in a mortar and suspended in acetone. The sticky suspension was then left to stand for 2 days, after which the deposited precipitate was filtered off and washed with acetone. The very hygroscopic mass was then placed in a vacuum

desiccator dried. The yield of reaction product was 29.3 g, corresponding to 77% of theory The compound formed a colorless, solid, hygroscopic mass.

F. 5.6-Dichloro-1-ethyl-2-methyl-3- (2-piperidinoathyDbenzimidazolium chloride hydrochloride

H. 5,6-dichloro-1-ethyl-2-methyl-

3- [2- (1 -pyrrolidinyljethyl] benzimidazolium-

chloride hydrochloride

CH,

cr

CH
ι " N
j CH
/ , CH, CH, • HCl ι
N
\ CH ₂ / \ \ 5 C-Cl CH ₇ N

CH ₂ CH ₂

CH ₂ CH ₂

HCl

CH ₂ CH,

A: mixture of 23 g of 5,6-dichloro-1-ethyl-2-rnethylbenzimidazol and 19 g l - ^ - Chldroäthylpiperidi: hydrochloride was heated for 1 hour on a Temperuur of 180 to 19O ⁰ C. The mixture became mushy and then solid. The cooled solid melt was crushed in a mortar. The hygroscopic solid mass obtained was quickly closed in a bottle and used without further purification. The yield of reaction product was 39 g, corresponding to 90% of theory. The reaction product formed a colorless solid, hygroscopic mass.

G. 5,6-Dichloro-1-ethyl-2-methyl-3- (2-morpholinoethyl) benzimidazolium chloride hydrochloride

A mixture of 23 g of 5,6-dichloro-1-ethyl-2-methylbenzimidazole and 17 g! - / i-chloroethylpyrrolidine hydrochloride was heated to a temperature of 190-195 ° C for 30 minutes. The mixture turned dark brown after melting together. The cooled down *. Mixture was then with acetone, namely three times with 150 ml each time, heated to the re-nut temperature. The acetone solutions were quenched whereupon the reaction product was filtered off. The hygroscopic solid mass obtained was dried in a vacuum desiccator. The yield of solid colorless reaction product was 15.3 g, corresponding to 36% of theory.

I. 5,6-dichloro-1-ethyl-2-methyl-

3- [2- (3-pyrrolin-1 -yl) ethyl] benzimidazolium

perchlorathyd roperchlorate

C-CH ₁

CH ₂ CH,

CH ₇ CH ₇ N

O · HCl

> -CH ₃ · HClO ₄

(CH ₂ ) ₂ ClO ₄ '

CH ₂ CH ₂

A mixture of 23 g of 5,6-dichloro-1-ethyl-2-methylbenzimidazole and 18.6 g of N-chloroethylmorpholine hydrochloride was added for 30 minutes heated to a temperature of 175 to 185 ° C. The melted mixture turned dark brown. The cooled melt was crushed in a mortar and suspended in acetone. The fixed one The mass was filtered off, washed with acetone and dried in a vacuum desiccator. There were a total of 38 g of reaction product corresponding to 91% of theory in the form of a colorless hygroscopic Mass received.

14.5 g of l- (2-chloroethyl) -3-pyrroline hydrochloride and 19.8 g of 5.6-dichloro-1-ethyl-2-methylbenzimidazole were heated together on an oil bath at a temperature of 185-190 ° C for minutes.

After cooling, the cake obtained was dissolved in boiling ethanol, and an aqueous solution of 25.0 g of sodium perchlorate was added to the hot solution. After cooling, the solid precipitate which had separated out was filtered off and dried. A total of 17.0 g of reaction product corresponding to 38% of theory with a melting point above 300 ° C. was obtained. On heating above 24O ⁰ C the reaction product was dark after.

The 1- (2-chloroethyl) -3-pyrroline hydrochloride used to prepare the intermediate formula

N-CH ₂ -CH ₂ -Cl ■ HCl

was prepared as follows: While stirring, 14.3 ml were added to a cold solution of 17.9 g of 1- (2-hydroxyethyl) -3-pyrroline, prepared as described in US Pat. No. 2,593,853, in 100 ml of chloroform Thionyl chloride was added dropwise, keeping the temperature at 15-20 ° C during the addition. After the addition had ended, the mixture was ^{stirred for a further 3 1} ₂ hours at room temperature. The mixture was then evaporated to dryness under reduced pressure and the residue was dissolved in boiling ethanol. The hot solution obtained was then filtered, whereupon the cooled filtrate was diluted by adding ethyl acetate. The reaction product precipitated on cooling. The precipitated solid reaction product was filtered off and dried in a vacuum oven at 65 ° C. The yield of reaction product was 14.5 g, corresponding to 54% of theory. The melting point of the reaction product was 154 to 155 ° C.

J. 5,6-Dichloro-! - / i-dimethylaminoethyl-S-ethyl-2-methylbenzimidazolium chloride hydrochloride A mixture of 22.9 g of 5,6-dichloro-1-ethyl-2-methylbenzimidazole and 17.2 g / i-diethylaminoethyl chloride hydrochloride was heated to a temperature of 165 to 170 ° C for 30 minutes. the

The mixture was melted in the process. After cooling and solidifying, it became the implementation The flask used in the reaction was smashed and the cake obtained was pounded in a mortar The obtained solid powdered mass became

ίο then heated to reflux temperature in acetone, whereupon the acetone was removed by filtration after cooling. The reaction mass then became boiled twice more in acetone. The reaction product was in the form of a colorless mass in

a yield of 31.7 g corresponding to 79% of theory with a melting point of 224 to 226 ° C (dec.) received.

L. 5,6-Dichloro-1- (3-dimethylaminopropy1 / -3-ethyl-2-methylbenzimidar , Uumchloridhydrochiorid

■ 5

C-CH ₃

CH ₂ CH ₂ CH ₂ N- (CH ₃ I ₂ • HCl

C-CH ₃

CH ₂ CH ₂ N- (CHj) ₂ ■ HCl

A mixture of 22.9 g of 5,6-dichloro-1-ethyl-2-methylbenzimidazole and 14.4 g of 0-dimethylaminoethyl chloride hydrochloride was added for 40 minutes heated to a temperature of 170 to 190 ° C. The mixture slowly melted together and formed a glass-like mass on cooling. The melt was then boiled several times with acetone, with it eventually became completely crystalline. This crystalline mass was filtered off and in one Vacuum desiccator dried. The yield of reaction product, which was obtained in the form of a colorless solid was 13.5 g, corresponding to 36% of the Theory.

K. 5,6-Dichloro-1 - / i-diethylaminoethyl-3-ethyl-2-methylbenzimidazolium chloride hydrochloride A mixture of 22.9 g of 5,6-dichloro-1-ethyl-2-methylbenzimidazole and 15.8 g of 3-chloro-N, N-dimethylpropylamine hydrochloride became 30 minutes

heated to a temperature of 170 to 180 ^{° C. for a long time.} The melted mixture changed to a glassy state on cooling. It was pounded in a mortar and then stirred with 500 ml of acetone for 1 hour. The solid mass was then filtered off and dried over potassium hydroxide in a vacuum desiccator. The reaction product was obtained in the form of a colorless, hygroscopic solid in a yield of 37 g, corresponding to 95% of theory.

M. 5,6-Dichloro-1 - [(2-dimethylamino-1-methyl) ethyl] -3-ethyl-2-methylbenzimidazolium chloride

hydrochloride

C ₂ H ₅

C-CH ₃ Cl '

CH ₃ -CHCH ₂ N- (CHj) ₂ • HCl

C-CH ₃

CH ₂ CH ₂ N- (C ₂ Hs) ₂ • HCl A mixture of 22.9 g 5,6-dichloro-1-ethy I-2-methylbenzimidazole and 15.8 g 2-chloro-N, N-dimethylpiopylamine hydrochloride was heated to a temperature of 170 to 180 ⁰ C for 35 minutes. The melted mixture changed to a glassy state on cooling. It was pounded in a mortar and dried in a vacuum desiccator. The reaction product

24

was in the form of a very hygroscopic mass in a yield of 31 g, corresponding to 80% of theory.

The following example is intended to illustrate the invention in more detail.

The dyes listed in the table below were each dissolved in a solvent, whereupon the solutions obtained have different proportions of the same light-sensitive photographic Silver halide emulsion was added.

In detail, the dyes were tested according to test methods A, B. C and / or D.

Test method A

The dyes were added to a gelatin silver bromoiodide emulsion, the silver halide of which consisted of 0.77 mol% of iodide and the preparation of which is described in more detail by T ri ν c 11 i and Smith in Phot. Journal. 79, 330 (1939). is described. After a digestion period of 10 minutes at 52 ° C., the emulsion samples were applied to conventional cellulose acetate film carriers in such a way that 432 mg of silver were ^{applied to a carrier surface of 0.09 m 2.} Samples of the test specimens obtained were then exposed to a step-wedge-shaped spectrograph in a scanner. Developed for 3 minutes at 20 ^° C. in a developer of the composition given below, fixed, washed and dried.

Developer composition

Water, about 50 "C: 500rn!

p-methylaminophenol sulfate 2.0 g

Sodium sulfite, dehydrated 90.0 g

Hydroquinone 8.0 g

Sodium carbonate, monohydrate 52.5 g

Potassium bromide 5.0 g

Filled up with cold water to ... 1.01

Test method B

It was described as in the case of test method A-K-n proceed, with the exception, however, that this time. a Gclatine silver chlorobromide emulsion. their silver halide 40 mol percent consisted of bromide, ■ · - was used.

Test method C

The dyes were dissolved in solvents and various proportions of the same fine-grain gelatin-überbroinoiodide emulsion. the silver halide of which contained 23 mole percent iodide was added. After digestion for 10 minutes at 40.degree. C., the emulsion samples were applied to cellulose acetate layer support in such a way that 100 mg of silver accounted for an area of 0.09 m ^2.

The samples were then exposed in a Semitometer by a Stufcnkeilspcklrographen developed for 6 minutes at 20 C ^r in a p-methylaminophenol sulfate-hydroquinone developer, fixed, washed and dried.

Test method D

The procedure was as in the case of test method C, with the exception that this time a gelatin-silver chlorobromide emulsion containing 90 mole percent chloride, 9 mole percent bromide and 1 mole percent iodide was used. The emulsions were applied to the support in such a way that a support area of 0.09 m ² accounted for 450 mg of silver. The specimens were then developed for 4 minutes at 20 ° C. in a developer of the specified composition, fixed, washed and dried.

The results obtained are summarized in the table below.

dye No

10

11th

12 13

14th

Kotv in
mg MnIAg F. emulsion type test Sens.
Max (nm) 300.0 BrI C. 550 100.0 ClBrI D. 565 300.0 BrI C. 550 100.0 ClBrI D. 550 300.0 BrI C. 570 50.0 ClBr! D. 550 300.0 BrI C. 575 300.0 BrI C. 570 100.0 BrI C. 640 300.0 BrI C. 595 150.0 D. 485 300.0 BrI C. 575 100.0 BrI C. 570 3.84 ClBr B. 565 2.56 BrI A. 575 2,> 6 BrI A. 575 4.16 ClBr B. 575 5.12 CIBr B. 50U 2.88 BrI A. 575 4.80 ClBr 6th 57S 2.88 BrI A. 575 4.80 ClBr B. 575

Sens Area

(nmi

to 620 to 635

to 620 to 635

to 620 to 620

up to 615 up to 620 up to 690

to 630 to 54C

up to 6IC

600

645
630

645
645

600

645 650

650 650

Claims (5)

2 2 Patent claims: ί. A photosensitive photographic silver halide emulsion containing one the emulsion Spectral sensitizing merocyanine dye, characterized in that it is a merocyanine dye contains the following structural formula: Ν— (CH = CH) _r —C = (CH- -C = O where means: R _{1 is} an alkylene radical with 2 to 6 carbon atoms, R ₂ and R ₃ individually alkyl radicals with 2 to 12 carbon atoms or aryl radicals or, together with the nitrogen atom on which they are attached, a heterocyclic radical with 4 or 5 ring atoms, k = 1 or 2,
π = 1, 2, 3 or 4, Q those required to complete a rhodanine or 2-thiobarbituric acid ring Atoms, with the proviso that the ring is connected to the methine radical via its carbon atom in the 5-position is bound, and Z to complete a ";> - or 6-membered basic heterocyclic ring of the type customary for merocyanine dyes required atoms. 2. Photosensitive photographic silver halide emulsion according to claim 1, characterized in that that it contains a merocyanine dye of the structural formula given, in which Z to complete one: Thiazole, oxazole, Selenazole, Thiazoline, Pyridine, Quinoline, 3,3-dialkylindolenine or Imidazole ring represents required atoms. 3. Photosensitive photographic silver halide emulsion according to claim 1, characterized in that that it contains a merocyanine dye of the structural formula given, in which Q has the meaning given and otherwise means η = 2,
/ c = l,
Z the atoms required to complete a benzimidazole ring, R _{1 is} an alkylene radical having 2 to 3 carbon atoms and R ₂ and R _{3 are} each an alkyl radical having 1 to 4 carbon atoms. 4. Photosensitive silver halide photographic emulsion according to claim 1, characterized in that it contains one of the following merocyanine dyes contains: 3-Ethyl-5- {[1 -ethyl-3- (2-morpholinoethyl) - 2-benzimidazolinylidene] ethylidene} rhod- anin;
3-ethyl-5-i [1-ethyl-5-methyl-3- (2-morpholinoethyl) ~ 2-benzimidazolinylidene] ethylidene} - rhodanine;
5- {[5-chloro-1-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene} - 3-ethylrhodanine;
5- {[5,6-dichloro-1-ethyl-3- {2-piperidinoethyl) -2-benzimidazolinylidene] ethylidene} - 3-ethylrhodanine;
5- {[5,6-dichloro-1-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene} - 3-ethylrhodanine;
5- {4- [5,6-dichloro-1-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] - 2-butenylidene} -3-ethylrhodanine; 5 - {[5,6-dichloro-l-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene} - 1,3-diethyl-2-thiobarbituric acid; 5 - [{5,6-Diciiloro-1-ethyl-3- [2- {1 -pyrrolidinyi) ethfayl] -2-benzimidazolinylidene} - ethylidene] -3-ethy! rhodanine; 5 - [{5,6-dichloro-1-ethyl-3- [2- (3-pyrrolinl-yl) ethyl] -2-benzimidazolinylidene} ethyl iden] -3-ethylrhodanine;
> {[5,6-dichloro-1- (2-dimethylaminoethyl) -3-ethyl-2-benzimidazolinylidene] ethylidene} - 3-ethylrhodanine;
5- {[5,6-dichloro-1 - (2-diethylaminoethyl) -3-ethyl-2-benzimidazolinylidene] ethylidene} - 3-ethylrhodanine;
5- {[5,6-dichloro-1 - (2-diethylaminoethyl) -3-ethyl-2-benzimidazolinylidene] ethylidene} - 1, S-diethyl-l-thiobarbituric acid; 5 - {[5,6-dichloro-1- (3-dimethylaminopropyl) -3-ethyl-2-benzimidazolinylidene] ethylidene} - 3-ethylrhodanine and
5 - {[5,6-dichloro-l - [(2-dimethylaminol-methyl) ethyl] -3-ethyl-2-benzimidazolynylidene] ethylidene} -3-ethylrhodanine. 5. Light-sensitive silver halide photographic emulsion according to claim 1, characterized indicates that it contains as merocyanine dye: 5-1 [5,6-dichloro-1 - (2-diethylaminoethyl) -3-ethyl-2-benzimidazolinylidene] ethylidene-3-ethylrhodanine. The invention relates to a photosensitive silver halide photographic emulsion containing a content on a merocyanine dye which spectrally sensitizes the emulsion. Ice is known to use merocyanine dyes for the spectral sensitization of photographic silver halide emulsions to use. Ice cream are still available (see example 9 of the French Patent 1460 985) merocyanine dyes with an oxazolidone nucleus. d. H. an acidic nucleus which is substituted by a tertiary aminoalkyl radical, known. The dye known from French patent specification 1,460,985 and also this one Dye structurally very similar dyes, viz 4 - {[5,6-dichloro-l-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene \ - 1,2-di- phenyl-3,5-pyrazolidinedione; 5- {[5,6-dichloro-1-ethyl-3- (2-morpholinoethyl) -2-benL; midazolinylidene] ethylidene} -3-ethyl- 2-thio-2,4-oxa7olidine ^); on; <M [5,6-dichloro-1-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene "'ethylidene} -3-phenyl- 2-isoxazolin-5-one and
4 - {[5,6-dichloro-1-ethyl-3- (2-morpholinoethyl) -2-benzimidazolinylidene] ethylidene} -3-methyl-1-phenyl-2-pyrazolin-5-one however, have the property that they do not affect the emulsions into which they are incorporated give the desired high blue sensitivity It has also been shown that merocyanine dyes, in which the nitrogen atom of the basic ring through a tertiary Amir.oalkylrest is substituted, have excellent solubility properties, excellent are spectral sensitizing dyes and that also emulsions to which such dyes have been incorporated, have a better incubation stability than those emulsions which Have merocyanine dyes with a tertiary aminoalkyl radical on the ketomethylene ring, as they are for example from U.S. Patent 3,384,486 are known. The object of the invention was therefore to find merocyanine dyes whose heterocyclic nitrogen atom of the basic ring is substituted by a tertiary aminoalkyl radical and which are distinguished due to particularly good incubation stability, excellent spectral sensitizing properties, favorable solubility in aqueous solvents and the excellent "chemical" Are sensitizers, i. H. Dyes which are added to the photographic emulsions to which they are incorporated impart high sensitivity to blue light. It has been found that merocyanine dyes are present with the desired properties when one of its rings consists of a rhodanine or 2-thiobarbituric acid ring, this rhodanine ring or thiobarbituric acid ring each with its carbon atom in 5-position via a double bond, a dimethine, tetramethine or hexamethine radical bonded to a basic heterocyclic ring of the type containing at least one nitrogen atom is, as it is usual for merocyanine dyes, and if also the nitrogen atom of this second ring through is substituted by a tertiary aminoalkyl radical. A tertiary aminoalkyl radical is to be understood as meaning radicals of the following structural formula: