DE4344164A1 - Photographic silver halide emulsion - Google Patents

Abstract

A photographic silver-halide emulsion which contains from 10<-7> to 10<-3> mol/mol of silver of a compound of the formula (I) <IMAGE> in which R1 is H or alkyl, R2 is alkyl, benzyl, phenyl or substituted phenyl, R3 and R4 are H, alkyl, alkoxy, halogen or nitro, and which has been matured by means of a combination of (a) at least one gold compound and (b) at least one compound which liberates Se<2-> or Se2<2-> ions, is distinguished by high sensitivity and steep gradation.

Description

The invention relates to a photographic silver halide emulsion, which is characterized by high maximum density, steep gradation, high sensitivity and fast ent distinguishes windability.

It is known that a high maximum density and rapid developability of a photographic material by using a fine grain Silver halide emulsion can be achieved.

By doping with Rh³⊕ and / or Ir⁴⊕ ions one obtains a material with steeper Gradation (DE-OS 22 26 877).

To silver halide emulsions of the type mentioned above with great sensitivity production, it is necessary to use chemical ripening Combination of gold and sulfur compounds (Ullmanns Ency encyclopedia of technical chemistry; 4th ed., Vol. 18, p. 424).

With these emulsions, flat swelling can be an undesirable side effect gradation occur, which leads to a flattening of the gradation and a rise in veil can lead. Furthermore, due to the necessary strong maturation, another Rise in veil, especially after storage at normal or elevated temperature, observed.  

These disadvantages are partially avoided if the silver halide emul sion before the start of ripening diindolyl disulfide (US 5 229 264).

The object of the invention was to better ver the disadvantages described avoid, so a fast developing and highly sensitive silver halide to produce emulsion, which is characterized by a steep gradation with simultaneous low rise in fog of the material during storage. A another goal was to improve threshold gradation and er low sensitivity to subliminal pre-exposure, e.g. B. Darkroom light.

This object was achieved in that the silver halide emulsion Diindolyl disulfide and chemical ripening with a combination of (a) at least one gold compound and (b) at least one compound that Se²- or releases Se₂² ions.

The invention thus ^relates to a photographic silver halide emulsion which contains 10 ^-7 to 10 ^-3 mol / mol of silver of a compound of the formula (I)

wherein
R₁ H or alkyl,
R₂ alkyl, benzyl, phenyl or substituted phenyl,
R₃, R₄ denote H, alkyl, alkoxy, halogen or nitro,
contains, and which is matured with a combination of (a) at least one gold compound and (b) at least one compound which releases Se² or Se₂² ions.

The silver halide emulsion according to the invention is preferably doped with 10 to 10 ^-4 mol / mol Ag Rh ³⁺ and / or Ir ⁴⁺ ions.

The emulsion is preferably ripened at a concentration of 2 x 10 ^-6 to 2 x 10 ^-4 mol gold compound / mol Ag and 10 ^-7 to 10 ^-5 mol selenium compound / mol Ag.

AgCl, AgBr, AgBrCl, AgBrI and AgBrClI come in as silver halides Consideration.

The silver halide _{emulsion according} to the invention preferably has a composition of AgCl _0.15 Br _0.85 to AgCl _0.999 Br _0.001 . Particularly clear effects are achieved with so-called chloride emulsions, ie silver chloride bromide emulsions with chloride proportions above 80, preferably above 95 mol%.

The silver halide emulsion according to the invention can be used for photographic Materials, especially for color negative paper and black and white negative paper be used.

Another object of the invention is therefore a photographic material with a support and at least one light-sensitive silver halide emulsion layer, characterized in that the at least one silver halide emulsion layer is a silver halide emulsion according to the invention
Suitable compounds for doping the silver halide emulsion according to the invention are e.g. B. Na₃RhCl₆ and Na₂IrCl₆. Other suitable compounds are described in European Patents 336 425, 336 426 and 336 427.

Suitable selenium compounds are:

Information on the production of the selenium ripening agents according to the invention can be found in
EP 476.345, EP 488.029, EP 506.009, EP 533.681, Journal of Chemistry 12 (3) [1972] 5. 91-100, Liebigs Am. Chem. 320 [1902] 5. 32-44, Houben-Weyl: Methods of Organic Chemistry Volume Ix, Pages 1180-1209, Volume XII / 2, Pages 95 and 835-841, Chem. Ber. 99 [1966] p. 3217, Khim. Heterotics Pay. 1990, 12, p. 1689, Coord. Chem. Rev. 100 [1990] pp. 223-265 and Synthesis [1976] 200.

Suitable gold ripening agents are e.g. B. H (AuCl₄) + KSCN, Na₃ [Au (S₂O₃) ₂] · 2H₂O and Gold rhodanine. Other gold ripening agents are from the German patent specifications 8 54 883 and 8 48 910 known.

The diindolyl disulfides according to the invention and their preparation are described in Chem. Pharm. Bull. 21 (1973), 2739. The diindolyl disulfides can during be added to the emulsion preparation. In a preferred embodiment are the compounds of the invention at any time after the end of crystal production and before the end of chemical ripening admitted. In a particularly preferred embodiment, the addition takes place just before chemical ripening begins.

The silver halide can be predominantly compact crystals, the z. B. are regular cubic or octahedral or have transitional forms can. However, platelet-shaped crystals, their average diameter to thickness ratio is greater than 3: 1, where the diameter of a grain is defined as the diameter of a circle with a circle content corresponding to the projected area of the grain.

The silver halide grains can also have a multi-layered grain structure have, in the simplest case with an inner and an outer grain area (core / shell), the halide composition and / or other modifications conditions such. B. doping of the individual grain areas are different. The average grain size of the emulsion is preferably between 0.2 μm and 2.0 μm, the grain size distribution can be both homodisperse and heterodisperse. The In addition to the silver halide, emulsions can also contain organic silver salts ten, e.g. B. silver benzotriazolate or silver behenate.

There can be two or more types of silver halide emulsions that are separated are produced, used as a mixture.  

The photographic emulsions can be prepared using various methods (e.g. P. Glalkides, Chimie et Physique Photographique, Paul Montel, Paris (1967), G.F. Duffin, Photographic Emulsion Chemistry, The Focal Press, London (1966), V.L. Zelikman et al., Making and Coating Photographic Emulsion, The Focal Press, London (1966) made from soluble silver salts and soluble halides become.

The silver halide is preferably precipitated in the presence of the binder, e.g. B. the gelatin and can in the acidic, neutral or alkaline pH range are performed, preferably silver halide complexing agents additionally ver be applied. The latter include e.g. B. ammonia, thioether, imidazole, ammo nium thiocyanate or excess halide. Merging the water Soluble silver salts and the halides are optionally carried out one after the other single-jet or at the same time according to the double-jet process or any Combination of both methods. The dosage with increasing Zu is preferred flow rates, being the "critical" feed rate at which just about none New germs arise, should not be exceeded. The pAg range can be selected vary widely within the precipitation, preferably the so-called pAg-controlled method used in which a certain pAg value is constant hold or a defined pAg profile is traversed during the precipitation. Next the preferred precipitation with excess halide is also the so-called in Verse precipitation possible with excess silver ions. Except through precipitation, the Silver halide crystals also through physical ripening (Ostwald ripening), in Presence of excess halide and / or silver halide complexes resources grow. The growth of the emulsion grains can even be predominant by Ostwald ripening, preferably a fine-grained, so-called Lippmann emulsion, mixed with a less soluble emulsion and last is redeemed.

During the precipitation and / or physical ripening of the silver halide Grains can also be salts or complexes of metals, such as Cd, Zn, Pb, Tl, Bi, Fe to be available.  

Furthermore, the precipitation can also take place in the presence of sensitizing dyes Complexing agents and / or dyes can be added to any Make the time ineffective, e.g. B. by changing the pH or by a oxidative treatment.

Gelatin is preferably used as the binder. However, this can be done entirely or in part by other synthetic, semi-synthetic or natural occurring polymers are replaced. Synthetic gelatin substitutes are for example polyvinyl alcohol, poly-N-vinyl pyrrolidone, polyacrylamides, poly acrylic acid and its derivatives, especially their copolymers. Naturally Occurring gelatin substitutes are, for example, other proteins such as Albu min or casein, cellulose, sugar, starch or alginates. Semi-synthetic gel Tine substitutes are usually modified natural products. Cellulose derivatives like Hydroxyalkyl cellulose, carboxymethyl cellulose and phthalyl cellulose and Gela tin derivatives obtained by reaction with alkylating or acylating agents or have been obtained by grafting polymerizable monomers Examples of this.

The binders should have a sufficient amount of functional groups have so that by reacting with suitable hardening agents sufficiently stable layers can be generated. Such functional groups are especially amino groups, but also carboxyl groups, hydroxyl groups and ak tive methylene groups.

The gelatin which is preferably used can be acidic or alkaline finally be preserved. The gelatin can be oxidized. The production of such Gelatins is found, for example, in The Science and Technology of Gelatine given by A.G. Ward and A. Courts, Academic Press 1977, page 295 ff ben. The gelatin used in each case should have the lowest possible photo content contain graphically active impurities (inert gelatin). Gelatins with high Viscosity and low swelling are particularly advantageous.  

After crystal formation has been completed or at an earlier point in time the soluble salts are removed from the emulsion, e.g. B. by pasta and Washing, by flaking and washing, by ultrafiltration or by ionizing exchanger.

The photographic emulsions can be used to prevent the compounds Fog formation or to stabilize the photographic function during the Production, storage or photographic processing included.

Azaindenes are particularly suitable, preferably tetra- and pentaazaindenes, in particular those which are substituted with hydroxyl or amino groups. Such connections are e.g. B. von Birr, Z. Wiss. Phot 47 (1952), pp. 2-58 have been described. Furthermore, salts of metals such as Mercury or cadmium, aromatic sulfonic or sulfinic acids such as benzene sulfinic acid, or nitrogen-containing heterocycles such as nitrobenzimidazole, nitro indazole, (subst.) Benztriazole or Benzthiazoliumsalze be used. Heterocycles containing mercapto groups, e.g. B. Mer captobenzthiazole, mercaptobenzimidazole, mercaptotetrazole, mercaptothiazole, Mercaptopyrimidines, these mercaptoazoles also being water-solubilizing Group, e.g. B. may contain a carboxyl group or sulfo group. Further suitable compounds are described in Research Disclosure No. 17643 (1978), Ab section VI, published.

The stabilizers can the silver halide emulsions before, during or after their maturation are added. Of course you can do the connections also other photographic layers associated with a halogen silver layer are to clog.

Mixtures of two or more of the compounds mentioned can also be used be used.

The photographic emulsion layers or other hydrophilic colloid layers of the Photosensitive material produced according to the invention can have surfaces  contain active agents for various purposes, such as coating aids change in the electrical charge, to improve the sliding properties, to Emulsifying the dispersion, to prevent adhesion and to improve the photographic characteristics (e.g. acceleration of development, high con trast, awareness, etc.).

The photographic emulsions can be made using methine dyes or other dyes are spectrally sensitized. Particularly suitable Dyes are cyanine dyes, merocyanine dyes and complex merocyanine dyes.

Sensitizers can be omitted if for a certain spectral range range the intrinsic sensitivity of the silver halide is sufficient, for example shows the blue sensitivity of silver bromide.

Suitable supports for the production of color photographic materials are e.g. B. Movies and Films of semi-synthetic and synthetic polymers, such as cellulose nitrate, Cellulose acetate, cellulose butyrate, polystyrene, polyvinyl chloride, polyethylene terephthalate and polycarbonate and with a baryta layer or α-olefin polymer layer (e.g. polyethylene) of laminated paper. These carriers can be dyed and pigments, for example titanium dioxide. You can also go to For the purposes of shielding light, be colored black. The surface of the Trä gers is generally subjected to a treatment to improve the adhesion of the photo to improve the graphic emulsion layer, for example a corona discharge with subsequent application for a substrate layer.

Color photographic materials usually contain at least one red each sensitive, green-sensitive and blue-sensitive emulsion layer. This one Emulsion layers become non-diffusing monomeric or polymeric paints assigned couplers that are in the same layer or in a neighboring layer Layer. Usually the red sensitive layers Teal couplers, the green-sensitive layers of purple couplers and the blue assigned to sensitive layers of yellow couplers.  

Color couplers for generating the blue-green partial color image are usually couplers phenol or α-naphthol type; suitable examples of this are in the Lite maturity known.

Color couplers for generating the yellow partial color image are usually couplers with an open chain catomethylene grouping, in particular type couplers α-acylacetamide; suitable examples are α-benzoylacetanilide couplers and α-pivaloylacetanilide couplers, which are also known from the literature.

Color couplers for generating the purple partial color image are usually Kupp 5-pyrazolone, indazolone or pyrazoloazole type; suitable Examples of this are described in large numbers in the literature.

The color couplers can be 4-equivalent couplers, but also 2-equi act valent coupler. The latter are derived from the 4 equivalent couplers from the fact that they contain a substituent in the coupling site, which in the coupling is split off. The 2-equivalent couplers include those that are colorless, as well as those that have an intense inherent color, which in the Color coupling disappears or he by the color of the image dye generated is set (mask coupler), and the white couplers, which react with color ent winder oxidation products result in essentially colorless products. To the 2-equivalent couplers are also to be expected such couplers in the coupling place a cleavable residue that, when reacted with color developer oxides tion products is released, either directly or afterwards split off the primary split off one or more other groups (e.g. DE-A-27 03 145, DE-A-28 55 697, DE-A-31 05 026, DE-A-33 19 428), exhibits a certain desired photographic effectiveness, e.g. B. as a development inhibitor or accelerator. Examples of such 2-equi valent couplers are the well-known DIR couplers as well as DAR and FAR couplers.

Since with the DIR, DAR and FAR couplers mainly the effectiveness of the the clutch released rest is desired and it less on the color  forming properties of these couplers, such DIR, DAR or FAR couplers, which are essentially colorless Pro products result (DE-A-15 47 640).

The cleavable residue can also be a ballast residue, so that in the reaction with Color developer oxidation products coupling products are obtained which are diffuse are capable of sion or at least weak or limited mobility (US-A-4 420556).

High molecular weight color couplers are described, for example, in DE-C-12 97 417, DE-A- 24 07 569, DE-A-31 48 125, DE-A-32 17 200, DE-A-33 20 079, DE-A-33 24 932, DE-A-33 31 743, DE-A-33 40 376, EP-A-27 284, US-AA 080211. The high molecular weight color couplers are usually obtained by polymerization of You can produce ethylenically unsaturated monomeric color couplers can also be obtained by polyaddition or polycondensation.

Incorporation of the couplers or other compounds into silver halide emulsions Sionsschichten can be done in such a way that first of the relevant Compound and then a solution, dispersion or emulsion the casting solution for the layer in question is added. The selection of the ge suitable solvent or dispersant depends on the respective solubility of the Connection off.

Methods for introducing a compound which is essentially insoluble in water solutions by grinding processes are for example in DE-A-26 09 741 and DE-A- 26 09 742.

Hydrophobic compounds can also be made using high-boiling solvents solvents, so-called oil formers, are introduced into the casting solution.

Appropriate methods are described, for example, in US-A-2 322 027, US-A-2 801170, US-A-2 801171 and EP-A-0 043037.  

Instead of the high-boiling solvents, oligomers or polymers, so mentioned polymeric oil formers are used.

The compounds can also be introduced into the casting solution in the form of loaded latices to be brought. Reference is made, for example, to DE-A-25 41 230, DE-A- 25 41 274, DE-A-28 35 856, EP-A-00 14 921, EP-A-00 69 671, EP-A-01 30 115, US-A-4291 113.

The diffusion-resistant storage of anionic water-soluble compounds (e.g. from Dyes) can also be used with the help of cationic polymers, so-called pickling polymeric.

Suitable oil formers are e.g. B. alkyl phthalates, phosphoric esters, lemons acid esters, benzoic acid esters, alkyl amides, fatty acid esters and trimesic acid esters.

Color photographic material typically includes at least one red sensitive Emulsion layer, at least one green-sensitive emulsion layer and min least a blue-sensitive emulsion layer on the carrier. The chronological order these layers can be varied as desired. Usually turn blue couplers forming green, purple and yellow dyes into the red, green and blue-sensitive emulsion layers incorporated. However, it can also be under different combinations can be used.

Each of the photosensitive layers can consist of a single layer or also comprise two or more silver halide emulsion partial layers (DE-C- 11 21 470). Red-sensitive silver halide emulsion layers are Layer supports are often arranged closer than green-sensitive silver halide emulsions sion layers and these, in turn, are closer than blue-sensitive layers generally between green sensitive layers and blue sensitive layers there is a non-light-sensitive yellow filter layer.

With suitably low intrinsic sensitivity of the green or red sensitive Layers can be arranged without the yellow filter layer  choose solutions where z. B. the blue-sensitive, then the red sensitive and finally the green sensitive layers follow.

The usually between layers of different spectral sensitivity arranged non-light-sensitive intermediate layers can contain agents which an undesirable diffusion of developer oxidation products from a light sensitive to another photosensitive layer with different prevent spectral sensitization.

If there are several sub-layers of the same spectral sensitization, then these with regard to their composition, especially what type and quantity regarding silver halide grains. In general, the Partial layer with higher sensitivity from the carrier be arranged as the sublayer with less sensitivity. Sub-layers of the same spectral Sensitization can be adjacent to each other or through other layers, e.g. B. be separated by layers of other spectral sensitization. So z. B. all highly sensitive and all low sensitive layers in one Layer package can be summarized (DE-A-19 58 709, DE-A-25 30 645, DE-A- 26 22 922).

The photographic material can also contain compounds that absorb UV light, Contains whites, spacers, filter dyes, formalin scavengers and others.

Compounds that absorb UV light are intended on the one hand to protect the image dyes from the Protect fading with UV-rich daylight and on the other hand as a filter color substances absorb the UV light in daylight during exposure and thus the color Improve movie playback. Usually for the two tasks Connections of different structures are used. Examples are aryl-substituted Benzotriazole compounds (US-A-3 533 794), thiazolidone compounds (US-A- 3 314 794 and 3 352 681), benzophenone compounds (JP-A-2784/71), cinnamic acid ester compounds (US-A-3,705,805 and 3,707,375), butadiene compounds (US-A-4 015 229) or benzoxazole compounds (US-A-3 700 455).  

Ultraviolet absorbing couplers (such as cyan couplers desα- Naphthol type) and ultraviolet absorbing polymers can be used. These Ultraviolet absorbents can be fixed in a special layer by pickling his.

Filter dyes suitable for visible light include oxonol dyes, hemi oxonol dyes, styrene dyes, merocyanine dyes, cyanine dyes and Azo dyes. Of these dyes are oxonol dyes, hemioxonol substances and merocyanine dyes used particularly advantageously.

Suitable whiteners are e.g. B. in Research Disclosure December 1978, page 22 ff. Unit 17 643, Chapter V.

Certain layers of binder, especially those furthest from the carrier distant layer, but also occasionally intermediate layers, especially if they represent the most distant layer from the support during manufacture, can contain photographically inert particles of inorganic or organic nature, e.g. B. as a matting agent or as a spacer (DE-A-33 31 542, DE-A- 34 24 893, Research Disclosure December 1978, page 22 ff, Unit 17643, Chapter XVI).

The average particle diameter of the spacers is in particular in the range from 0.2 to 10 µm. The spacers are insoluble in water and can be alkaline be soluble or alkali-soluble, the alkali-soluble in general in alk development bath can be removed from the photographic material. Example Suitable polymers are polymethyl methacrylate, copolymers of acrylic acid and methyl methacrylate and hydroxypropyl methyl cellulose hexahydrophthalate.

The binders of the material according to the invention, especially when used as a binding medium gelatin is used, are hardened with suitable hardeners, for example as with hardeners of the epoxy type, the ethyleneium type, the acryloyl type or the Vinyl sulfone types. Hardeners of diazine, triazine or 1,2-dihydro are also suitable quinoline series.  

The binders of the material according to the invention are preferably immediately hardened hardened.

Immediate hardeners are understood to mean compounds which are suitable binders network, preferably immediately after watering, at the latest after 24 hours after 8 hours at the latest the hardening is complete to the extent that no further change in the sensitometry and the source caused by the crosslinking reaction layer structure occurs. The difference between wet and swelling layer thickness and dry layer thickness in the aqueous processing of the film understood (Photogr. Sci. Eng. 8 (1964), 275; Photogr. Sci. Eng. (1972), 449).

These hardeners react very quickly with gelatin e.g. B. carbamoylpyridinium salts with free carboxyl groups of gelatin able to react, so that the latter with free amino groups of the gelatin Formation of peptide bonds and crosslinking of the gelatin react.

Suitable examples of instant hardeners are e.g. B. in the European patent specification 313,949.

The materials according to the invention are produced according to the processes recommended for this processed in the usual way.

example 1

The following solutions are made up with demineralized water:

Solution 1:

7000 ml of water
540 g gelatin

Solution 2:

7000 ml of water
1300 g NaCl
21.5 g KBr
5 · 10 ^-5 g K₂IrCl₆
3 · 10 ^-5 g Na₃RhCl₆
2 · 10 ^-6 g HAuCl₄
1.5 · 10 ^-4 g PtCl₄

Solution 3:

7000 ml of water
3000 g AgNO₃

Solutions 2 and 3 are simultaneously added to solution 1 at 50 ° C. in the course of 120 minutes at a pAg of 7.7 with vigorous stirring. A silver chloride emulsion with an average particle diameter of 0.8 μm is obtained. The gelatin / AgNO₃ weight ratio is 0.18. The emulsion is flocked in a known manner, washed and redispersed with so much gelatin that the gelatin / AgNO₃ weight ratio is 1.0. The emulsion contains 1 mol of silver halide per kg. It is then optimally ripened at a pH of 4.5 with 3.5 mol of gold chloride / mol of Ag and 1.5 μmol of Na₂S₂O molAg. After chemical ripening, the emulsion (silver halide composition: AgCl _0.99 Br _0.01 ) is stabilized and sensitized to the blue spectral range.

Then the emulsion with a solution of the yellow coupler of the formula

and the white coupler of the formula

in tricresyl phosphate and on a support from both sides with Polyethylene coated paper applied.

The layer contains per m²
0.63 g AgNO₃,
1.38 g gelatin 1,
0.95 g yellow coupler,
0.2 g white coupler,
0.29 g tricresyl phosphate.

A protective layer of 0.2 g gelatin and 0.3 g hardness is applied over this layer means of the formula

cast per m². The material is exposed imagewise and after the Ektacolor RA 4 process processed

Example 2

The emulsion is prepared and processed as described in Example 1, however with the difference that the chemical ripening before the addition of thiosulfate 4.5 mg of diphenylindolyl disulfide were added as a 0.1% by weight acetone solution become.

Example 3

The emulsion is prepared and processed as described in Example 1, however with the difference that chemical ripening instead of 1.5 µmol Sodium thiosulfate 1.5 μmol of the selenium compound 6 are added.

Example 4

An emulsion is prepared according to Example 3, with the difference that the Emulsion before adding the gold and selenium compound 4.5 mg diphenyl indolyl disulfide can be added as a 0.1% by weight acetone solution.  

Example 5

An emulsion is prepared according to Example 4, but the addition is Diphenylindolyl disulfide 225 mg.

Example 6

An emulsion is prepared according to Example 4, but instead of Selenium compound 61.5 µmol / mol Ag of selenium compound 1 added.

The sensitometric results are shown in Table 1.

Table 1

Example 7

The following solutions are made up with demineralized water:

Solution 1:

8000 ml of water
360 g gelatin
10 g NaCl

Solution 2:

6000 ml of water
390 g NaCl
700 g KBr
4 · 10 ^-4 g Na₃RhCl₆

Solution 3:

6000 ml of water
2000 g AgNO₃.

Solutions 2 and 3 are simultaneously added to solution 1 at 55 ° C. in the course of 60 minutes at a pAg of 7.8 with vigorous stirring. The emulsion is flocculated in a known manner, washed and redispersed with the addition of gelatin, phenol (as a preservative) and water. The emulsion contains 0.9 mol of silver halide per kg. Subsequently, with the addition of 10 µmol HAuCl₄ / mol Ag and 20 µmol Na₂S₂O₃ / mol Ag 120 minutes at 52 ° C. Then the emulsion (silver halide composition: AgCl _0.5 Br _0.5 ) is poured onto a paper support coated on both sides with polyethylene with the addition of sensitizers, stabilizers, plasticizer latex, optical brighteners, developer substances and hardening agents. The material is exposed imagewise and processed according to the AGFA 100 recipe.

Example 8

The emulsion is prepared and processed as described in Example 7, however with the difference that in chemical ripening before the addition of the ripening punch 160 mg of diphenylindolyl disulfide can be added.  

Example 9

The emulsion is prepared and processed as described in Example 7. The However, the sensitometric data are only measured after a two-day period Storage at 60 ° C.

Example 10

The emulsion is prepared and processed as described in Example 8. The However, the sensitometric data are only measured after a two-day period Storage at 60 ° C.

Example 11

The emulsion is prepared and processed as described in Example 7. The However, the sensitometric data are measured after diffuse exposure Amber filter (corresponds to the draft standard ISO / DIS 8374).

Example 12

The emulsion is prepared and processed as described in Example 8. The However, the sensitometric data are measured after diffuse exposure Amber filter (corresponds to the draft standard ISO / DIS 8374).

Example 13

The emulsion is prepared and processed as in Example 7, but in the Maturation of sodium thiosulfate replaced by 20 µmol selenium compound 6 / mol Ag.  

Example 14

The emulsion is prepared and processed as in Example 13, but before the addition of the gold and selenium compounds to 160 mg diphenylindolyl disulfide set.

Example 15

The emulsion is prepared and processed according to Example 13. The measurement of However, sensitometric data is only provided after a two-day storage 60 ° C.

Example 16

The emulsion is prepared and processed according to Example 14. The measurement of However, sensitometric data is only provided after a two-day storage 60 ° C.

Example 17

The emulsion is prepared and processed according to Example 13. The measurement of However, sensitometric data is only carried out after diffuse exposure Amber filter according to example 11.

Example 18

The emulsion is prepared and processed according to Example 14. The measurement of However, sensitometric data is only carried out after diffuse exposure Amber filter according to example 11.

The sensitometric results are shown in Table 2.  

Table 2

Claims (5)

1. Photographic silver halide emulsion containing 10 ^-7 to 10 ^-3 mol / mol silver of a compound of formula (I) wherein
R₁ H or alkyl,
R₂ alkyl, benzyl, phenyl or substituted phenyl,
R₃, R₄ H, alkyl, alkoxy, halogen or nitro
mean, and which is ripened with a combination of (a) at least one gold compound and (b) at least one compound which releases Se ^2- or Se₂ ^2- ions. 2. Photographic silver halide emulsion according to claim 1, characterized in that the emulsion is doped with 10 ^-9 to 10 ^-4 mol / mol of Ag Rh ³⁺ - and / or Ir ⁴⁺ ions. 3. Photographic silver halide emulsion according to claim 1, characterized in that 2 · 10 ^-6 to 2 · 10 ^-4 mol of gold compound and 10 ^-7 to 10 ^-5 mol of selenium compound per mol of silver are used to ripen the emulsion. 4. Photographic silver halide emulsion according to claim 1, characterized in that the emulsion has a composition of AgCl _0.15 Br _0.85 to AgCl _0.999 Br _0.001 . 5. Photographic material with a support and at least one light sensitive silver halide emulsion layer, characterized in that that the silver halide emulsion layer after a silver halide emulsion Claim 1 contains.