EP0313949B1 - Colour-photographic silver halide material - Google Patents

Description

The invention relates to a silver halide color photographic material which is chemically sensitized in a special way, in particular to a color negative paper which contains in at least one layer a silver halide emulsion which consists essentially of silver chloride.

It is known to subject silver halide emulsions to combined sulfur / gold ripening (for example DE-A-22 63 910), gold being used in the form of inorganic gold salts. In the case of silver halide emulsions, which consist essentially of silver chloride, this leads to emulsions which have sufficient sensitivity but only show a flat gradation. Usual ways of dividing the gradation, for example rhodium doping, lead to sensitivity losses, particularly in the case of the blue-sensitized layer of a color negative paper, the sensitivity which is usually the lowest layer compared to the green- and red-sensitized layers is disadvantaged anyway, cannot be accepted.

The object of the invention was to provide a color photographic silver halide material which has sufficient sensitivity in combination with a steep gradation in all color layers, at least one color layer containing a silver halide emulsion which consists essentially of silver chloride.

entspricht, worin
R₁, R₂ und R₃ unabhängig voneinander Wasserstoff oder Alkyl und X^⊖ ein Anion, insbesondere Halogenid, vorzugsweise Chlorid, bedeuten, eingesetzt wird.It has now been found that this object can be achieved if the silver halide emulsion consisting essentially of silver chloride is subjected to gold / sulfur ripening, in which a compound of the formula ## STR7 ## is used as the gold compound

corresponds to what
R₁, R₂ and R₃ independently of one another are hydrogen or alkyl and X ^{⊖ is} an anion, in particular halide, preferably chloride, is used.

worin R₁, R₂ und R₃ unabhängig voneinander Wasserstoff oder Alkyl und X^⊖ ein Anion bedeuten, optimal gereift ist.The invention therefore relates to a color photographic silver halide material with at least one blue-sensitive one sensitive layer, which is associated with a yellow coupler, at least one green-sensitive layer, which is associated with a purple coupler, and at least one red-sensitive layer, which is associated with a cyan coupler, at least one layer containing a silver halide emulsion with 95 to 100 mol% of chloride, which with a Combination of at least one sulfur ripening body and at least one compound of the formula

wherein R₁, R₂ and R₃ independently of one another are hydrogen or alkyl and X ^{⊖ is} an anion, has matured optimally.

The silver halide emulsion ripened according to the invention is in particular the blue-sensitized emulsion. All emulsions preferably consist of 95 to 100 mol% of chloride. The emulsions also contain 0 to 5 mol% of bromide, iodide and rhodanide, individually or in combination, these halides and pseudohalides being preferably used in particular in the following amounts: 0.01 to 0.5 mol% of iodide, 0.02 to 5 mol% bromide and 0.02 to 5 mol% rhodanide.

Compounds capable of forming silver sulfide generally come as sulfur ripening bodies, e.g. Thiosulfate, thiourea, thiosemicarbazide and thiocarbamide, in question. Preferably 0.5 to 20 µg / g Ag are used. Thiosulfate is preferred.

In the above formula, R₁ and R₂ are preferably methyl, R₃ is hydrogen. The gold compound used is in particular 0.5 to 20 μg / g Ag, particularly preferably 1 to 10 μg / g Ag.

In a further preferred embodiment, the emulsions are iridium-doped, the amount of iridium being 0.01 to 0.5 μg / g Ag.

The emulsion ripened according to the invention shows the desired steep gradation both in the threshold area and in the shoulder area without loss of sensitivity.

The silver halide can be predominantly compact crystals which are, for example, regularly cubic or octahedral or can have transitional forms. However, platelet-shaped crystals can also preferably be present, the average ratio of diameter to thickness of which is preferably less than 8: 1, the diameter of a grain being defined as the diameter of a circle with a circle content corresponding to the projected area of the grain. However, the layers can also have tabular silver halide crystals in which the ratio of diameter to thickness is greater than 8: 1.

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

Two or more kinds of silver halide emulsions, which are prepared separately, can be used as a mixture.

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

The silver halide is preferably precipitated in the presence of the binder, for example the gelatin, and can be carried out in the acidic, neutral or alkaline pH range, silver halide complexing agents preferably being additionally used. The latter include, for example, ammonia, thioether, imidazole, ammonium thiocyanate or excess halide. The water-soluble silver salts and the halides are combined either in succession by the single-jet process or simultaneously by the double-jet process or by any combination of the two processes. Dosing with increasing inflow rates is preferred, the "critical" feed rate, at which no new germs are being produced, should not be exceeded. The pAg range can vary within wide limits during the precipitation, preferably the so-called pAg-controlled method is used, in which a certain pAg value is kept constant or a defined pAg profile is traversed during the precipitation. In addition to the preferred precipitation with an excess of halide, so-called inverse precipitation with an excess of silver ions is also possible. In addition to precipitation, the silver halide crystals can also grow through physical ripening (Ostwald ripening), in the presence of excess halide and / or silver halide complexing agent. The growth of the emulsion grains can even take place predominantly by Ostwald ripening, a fine-grained, so-called Lippmann emulsion preferably being mixed with a less soluble emulsion and being redissolved on the latter.

Salts or complexes of metals such as Cd, Zn, Pb, Tl, Bi, Ir, Rh, Fe can also be present during the precipitation and / or physical ripening of the silver halide grains.

The precipitation can also be carried out in the presence of sensitizing dyes. Complexing agents and / or dyes can be rendered ineffective at any time, e.g. by changing the pH or by an oxidative treatment.

Gelatin is preferably used as the binder. However, this can be replaced in whole or in part by other synthetic, semi-synthetic or naturally occurring polymers. Synthetic gelatin substitutes are, for example, polyvinyl alcohol, poly-N-vinylpyrolidone, polyacrylamides, polyacrylic acid and their derivatives, in particular their copolymers. Naturally occurring gelatin substitutes are, for example, other proteins such as albumin or casein, cellulose, sugar, starch or alginates. Semi-synthetic gelatin substitutes are usually modified natural products. Examples of these are cellulose derivatives such as hydroxyalkyl cellulose, carboxymethyl cellulose and phthalyl cellulose and gelatin derivatives which have been obtained by reaction with alkylating or acylating agents or by grafting on polymerizable monomers.

The binders should have a sufficient amount of functional groups so that enough resistant layers can be produced by reaction with suitable hardening agents. Such functional groups are in particular amino groups, but also carboxyl groups, hydroxyl groups and active methylene groups.

The gelatin which is preferably used can be obtained by acidic or alkaline digestion. The gelatin can be oxidized. The production of such gelatins is described, for example, in The Science and Technology of Gelatine, published by A.G. Ward and A. Courts, Academic Press 1977, page 295 ff. The gelatin used in each case should contain the lowest possible level of photographically active impurities (inert gelatin). High viscosity, low swelling gelatins 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. by pasta and washing, by flakes and washing, by ultrafiltration or by ion exchangers.

The photographic emulsions may contain compounds to prevent fogging or to stabilize the photographic function during production, storage or photographic processing.

Azaindenes are particularly suitable, preferably tetra- and penta-azaindenes, in particular those which are substituted by hydroxyl or amino groups. Such connections are e.g. B. von Birr, Z. Wiss. Phot. 47 (1952), pp. 2-58. Salts of metals such as mercury or cadmium, aromatic sulfonic or sulfinic acids such as benzenesulfinic acid, or nitrogen-containing heterocycles such as nitrobenzimidazole, nitroindazole, (subst.) Benzotriazoles can also be used as antifoggants or benzothiazolium salts can be used. Heterocycles containing mercapto groups, for example mercaptobenzthiazoles, mercaptobenzimidazoles, mercaptotetrazoles, mercaptothiadiazoles, mercaptopyrimidines, are particularly suitable, these mercaptoazoles also being able to contain a water-solubilizing group, for example a carboxyl group or sulfo group. Other suitable compounds are published in Research Disclosure No. 17643 (1978), Section VI.

The stabilizers can be added to the silver halide emulsions before, during or after their ripening. Of course, the compounds can also be added to other photographic layers which are assigned to a halogen silver layer.

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

The photographic emulsion layers or other hydrophilic colloid layers of the light-sensitive material produced according to the invention can contain surface-active agents for various purposes, such as coating aids, to prevent electrical charging, to improve the sliding properties, to emulsify the dispersion, to prevent adhesion and to improve the photographic characteristics ( eg acceleration of development, high contrast, sensitization etc.).

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

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

Color photographic materials usually contain at least one red-sensitive, green-sensitive and blue-sensitive emulsion layer. These emulsion layers are assigned non-diffusing monomeric or polymeric color couplers, which can be located in the same layer or in a layer adjacent to it. Usually cyan couplers are assigned to the red-sensitive layers, purple couplers to the green-sensitive layers and yellow couplers to the blue-sensitive layers.

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

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

Color couplers for producing the purple partial color image are generally couplers of the 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-equivalent couplers. The latter are derived from the 4-equivalent couplers in that they contain a substituent in the coupling site which is split off during the coupling. The 2-equivalent couplers include those that are colorless, as well as those that have an intense intrinsic color that disappears when the color is coupled or is replaced by the color of the image dye produced (mask coupler), the white couplers that react with Color developer oxidation products result in essentially colorless products. The 2-equivalent couplers also include those couplers that contain a cleavable residue in the coupling point, which is released upon reaction with color developer oxidation products and thereby either directly or after one or more further groups have been cleaved from the primarily cleaved residue ( eg DE-A-27 03-145, DE-A-28 55 697, DE-A-31 05 026, DE-A-33 19 428), a certain desired photographic activity unfolds, for example as a development inhibitor or accelerator. Examples of such 2-equivalent couplers are the known DIR couplers as well as DAR or. FAR coupler.

Since with DIR, DAR or FAR couplers the effectiveness of the residue released during coupling is mainly desired and the color-forming properties of these couplers are less important, such DIR, DAR or FAR couplers are also suitable, which give essentially colorless products on coupling (DE-A-1 547 640).

The cleavable residue can also be a ballast residue, so that upon reaction with color developer oxidation products coupling products are obtained which are diffusible or at least have a weak or restricted mobility (US Pat. No. 4,420,556).

High molecular weight color couplers are described, for example, in DE-C-1 297 417, 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-A-4 080 211. The high molecular weight color couplers are usually produced by polymerizing ethylenically unsaturated monomeric color couplers. However, they can also be obtained by polyaddition or polycondensation.

The couplers or other compounds can be incorporated into silver halide emulsion layers by first preparing a solution, a dispersion or an emulsion of the compound in question and then adding it to the casting solution for the layer in question. Choosing the right one Solvents or dispersants depend on the solubility of the compound.

Methods for introducing compounds which are essentially insoluble in water by grinding processes are described, for example, in DE-A-2 609 741 and DE-A-2 609 742.

Hydrophobic compounds can also be introduced into the casting solution using high-boiling solvents, so-called oil formers. Corresponding methods are described for example in US-A-2 322 027, US-A-2 801 170, US-A-2 801 171 and EP-A-0 043 037.

Instead of the high-boiling solvents, oligomers or polymers, so-called polymeric oil formers, can be used.

The compounds can also be introduced into the casting solution in the form of loaded latices. Reference is made, for example, to DE-A-2 541 230, DE-A-2 541 274, DE-A-2 835 856, EP-A-0 014 921, EP-A-0 069 671, EP-A-0 130 115, U.S.-A-4,291,113.

The diffusion-resistant incorporation of anionic water-soluble compounds (eg dyes) can also be carried out with the aid of cationic polymers, so-called pickling polymers.

Suitable oil formers are e.g. Alkyl phthalates, phosphoric acid esters, citric acid esters, benzoic acid esters, alkylamides, fatty acid esters and trimesic acid esters.

Color photographic material typically comprises at least one red-sensitive emulsion layer, at least one green-sensitive emulsion layer and at least one blue-sensitive emulsion layer on a support. The order of these layers can be varied as desired. Couplers which form blue-green, purple and yellow dyes are usually incorporated into the red, green or blue-sensitive emulsion layers. However, different combinations can also 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-1 121 470). Red-sensitive silver halide emulsion layers are often arranged closer to the layer support than green-sensitive silver halide emulsion layers and these are in turn closer than blue-sensitive layers, a non-light-sensitive yellow filter layer generally being located between green-sensitive layers and blue-sensitive layers.

With a suitably low intrinsic sensitivity of the green or red-sensitive layers, other layer arrangements can be chosen without the yellow filter layer, in which, for example, the blue-sensitive, then the red-sensitive and finally the green-sensitive layers follow on the support.

The non-light-sensitive intermediate layers, which are generally arranged between layers of different spectral sensitivity, can contain agents which prevent undesired diffusion of developer oxidation products from one light-sensitive layer into another light-sensitive layer with different spectral sensitization.

If there are several sub-layers of the same spectral sensitization, these can differ with regard to their composition, in particular with regard to the type and amount of the silver halide grains. In general, the sublayer with higher sensitivity will be located further from the support than the sublayer with lower sensitivity. Partial layers of the same spectral sensitization can be adjacent to one another or through other layers, e.g. separated by layers of other spectral sensitization. For example, all highly sensitive and all low-sensitive layers can be combined to form a layer package (DE-A 1 958 709, DE-A 2 530 645, DE-A 2 622 922).

The photographic material may further contain compounds absorbing UV light, whiteners, spacers, filter dyes, formalin scavengers and others.

Compounds that absorb UV light are intended on the one hand to protect the image dyes from fading by UV-rich daylight and, on the other hand, as filter dyes to absorb the UV light in daylight upon exposure and thus improve the color rendering of a film. Connections of different structures are usually used for the two tasks. Examples are aryl substituted benzotriazole compounds (US-A 3 533 794), 4-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 4 045 229) or benzoxazole compounds (US-A 3 700 455).

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

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

Suitable whiteners are described, for example, in Research Disclosure December 1978, page 22 ff, Unit 17 643, Chapter V.

Certain binder layers, in particular the most distant layer from the support, but also occasionally intermediate layers, especially if they are the most distant layer from the support during manufacture, may contain photographically inert particles of inorganic or organic nature, e.g. as a matting agent or as a spacer (DE-A 3 331 542, DE-A 3 424 893, Research Disclosure December 1978, page 22 ff, Unit 17 643, Chapter XVI).

The average particle diameter of the spacers is in particular in the range from 0.2 to 10 μm. The spacers are water-insoluble and can be alkali-insoluble or alkali-soluble, the alkali-soluble ones generally being removed from the photographic material in the alkaline development bath. Examples of 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, in particular if gelatin is used as the binder, are hardened with suitable hardeners, for example with hardeners of the epoxy type, the ethyleneium type, the acryloyl type or the vinylsulfone type. Diazine, triazine or 1,2-dihydroquinoline series hardeners are also suitable.

The binders of the material according to the invention are preferably hardened with instant hardeners.

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

These hardening agents that react very quickly with gelatin are e.g. to carbamoylpyridinium salts, which are able to react with free carboxyl groups of the gelatin, so that the latter react with free amino groups of the gelatin to form peptide bonds and crosslink the gelatin.

worin
Suitable examples of instant hardeners are, for example, compounds of the general formulas

wherein

R₁ denotes alkyl, aryl or aralkyl,

verknüpft ist, oderR₂ has the same meaning as R₁ or means alkylene, arylene, aralkylene or alkaralkylene, the second bond having a group of the formula

is linked, or

R₁ and R₂ together represent the atoms necessary to complete an optionally substituted heterocyclic ring, e.g. a piperidine, piperazine or morpholine ring, the ring e.g. can be substituted by C₁-C₃-alkyl or halogen,

oder ein Brückenglied oder eine direkte Bindung an eine Polymerkette steht, wobeiR₃ for hydrogen, alkyl, aryl, alkoxy, -NR₄-COR₅, - (CH₂) _m -NR₈R₉, - (CH₂) _n -CONR₁₃R₁₄ or

or a bridge link or a direct bond to a polymer chain, wherein

R₄, R₆, R₇, R₉, R₁₄, R₁₅, R₁₇, R₁₈, and R₁₉
Hydrogen or C₁-C₄-alkyl,

R₅ is hydrogen, C₁-C₄-alkyl or NR₆R₇,

R₈ -COR₁₀

R₁₀ NR₁₁R₁₂

R₁₁ C₁-C₄ alkyl or aryl, especially phenyl,

R₁₂ is hydrogen, C₁-C₄ alkyl or aryl, especially phenyl,

R₁₃ is hydrogen, C₁-C₄ alkyl or aryl, especially phenyl,

m

eine Zahl 1 bis 3

n

eine Zahl 0 bis 3

p

eine Zahl 2 bis 3 und

Y

0 oder NR₁₇ bedeuten oder

R₁₆ is hydrogen, C₁-C₄-alkyl, COR₁₈ or CONHR₁₉,

m

a number 1 to 3

n

a number 0 to 3

p

a number 2 to 3 and

Y

0 or NR₁₇ mean or

R₁₃ and R₁₄ together represent the atoms necessary to complete an optionally substituted heterocyclic ring, for example a piperidine, piperazine or morpholine ring, which ring can be substituted by C₁-C₃-alkyl or halogen, for example,

Z the C atoms and required to complete a 5- or 6-membered aromatic heterocyclic ring, optionally with a fused benzene ring

worin
X ^{⊖ is} an anion which is omitted if an anionic group is already linked to the rest of the molecule;

wherein

R₁, R₂, R₃ and X ^{⊖ have} the meaning given for formula (a).

The materials according to the invention, be it color negative or color reversal films, color negative or color reversal paper or direct positive materials, are processed in the usual manner according to the processes recommended for this.

Manufacture of gold rhodanine

werden in 400 ml Methanol gelöst. Die Lösung wird mit Wasser auf 800 ml verdünnt und auf 15°C abgekühlt. Zu dieser Lösung gibt man 2 ml einer 40 gew.-%igen wäßrigen Lösung von AuCl₃·HCl unter Rühren, filtriert den Niederschlag ab, wäscht ihn einmal mit Methanol und zweimal mit 15°C-kaltem Wasser und trocknet ihn bei Raumtemperatur im Exsiccator über Silicagel.1.28 g of dimethylrhodanine of the formula

are dissolved in 400 ml of methanol. The solution is diluted to 800 ml with water and cooled to 15 ° C. 2 ml of a 40% by weight aqueous solution of AuCl₃ · HCl are added to this solution with stirring, the precipitate is filtered off, washed once with methanol and twice with 15 ° C. cold water and dried at room temperature in a desiccator Silica gel.

Emulsion production

In a double inlet at a constant pAG of 7.7 AgNO₃ as a 3-molar aqueous solution on the one hand and an aqueous solution of the desired halide or halides on the other hand are added to a reaction vessel at 50 ° C. with stirring. The halide solution is added Na₂IrCl₆. The halide compositions used in each case can be found in the tables below, bromide as KBr, iodide as KI, chloride as KCl and rhodanide as KSCN.

example 1

• 1. Eine Substratschicht aus 200 mg Gelatine mit KNO₃- und Chromalaunzusatz.
• 2. Eine Haftschicht aus 320 mg Gelatine.
• 3. Eine blauempfindliche Silberbromidchloridemulsionsschicht (99 mol-% Chlorid) aus 450 mg AgNO₃ mit 1600 mg Gelatine, 1,0 mmol Gelbkuppler, 27,7 mg 2,5-Dioctylhydrochinon und 650 mg Trikresylphosphat.
  
  Die Emulsion wurde durch Doppeleinlauf mit einer mittleren Korngröße von 0,8 µm hergestellt, in der üblichen Weise geflockt, gewaschen und mit Gelatine redispergiert. Das Gewichtsverhältnis Gelatine-Silber (als AgNO₃) betrug 0,5. Die Emulsion wurde anschließend mit 15 µmol Thiosulfat und 1 µmol Goldthiosulfat pro mol Ag zur optimalen Empfindlichkeit gereift, für den blauen Spektralbereich sensibilisiert und stabilisiert.
• 4. Eine Zwischenschicht aus 1200 mg Gelatine, 80 mg 2,5-Dioctylhydrochinon und 100 mg Trikresylphosphat.
• 5. Eine grünempfindliche Silberbromidchloridemulsionsschicht (99 mol-% Chlorid) aus 530 mg AgNO₃ mit 750 mg Gelatine, 0,625 mmol Purpurkuppler, 118 mg α-(3-t-Butyl-4-hydroxyphenoxy)-myristinsäureethylester, 43 mg 2,5-Dioctylhydrochinon, 343 mg Dibutylphthalat und 43 mg Trikresylphosphat (mittlere Korngröße 0,4 µm, Reifung: 20 µmol Thiosulfat + 5 µmol Goldthiosulfat pro mol Ag).
• 6. Eine Zwischenschicht aus 1550 mg Gelatine, 285 mg eines UV-Absorbers der Formel
  
  80 mg Dioctylhydrochinon und 650 mg Trikresylphosphat.
• 7. Eine rotempfindliche Silberbromidchloridemulsionsschicht (99 mol-% Chlorid) aus 400 mg AgNO₃ mit 1470 mg Gelatine, 0,780 mmol Blaugrünkuppler, 285 mg Dibutylphthalat und 122 mg Trikresylphosphat (mittlere Korngröße 0,3 µm, Reifung: 20 µmol Thiosulfat + 8 µmol Goldthiosulfat pro mol Ag).
• 8. Eine Schutzschicht aus 1200 mg Gelatine, 134 mg eines UV-Absorbers gemäß 6. Schicht und 240 mg Trikresylphosphat.
• 9. Eine Härtungsschicht aus 400 mg Gelatine und 400 mg Härtungsmittel der Formel

A layer support made of paper coated on both sides with polyethylene was provided with the following layers. The quantities refer to 1 m².

• 1. A substrate layer of 200 mg of gelatin with KNO₃- and Chromalaunzusatz.
• 2. An adhesive layer made of 320 mg of gelatin.
• 3. A blue-sensitive silver bromide chloride emulsion layer (99 mol% chloride) from 450 mg AgNO₃ with 1600 mg gelatin, 1.0 mmol yellow coupler, 27.7 mg 2,5-dioctylhydroquinone and 650 mg tricresyl phosphate.
  
  The emulsion was prepared by double inlet with an average grain size of 0.8 μm, flocculated in the usual way, washed and redispersed with gelatin. The weight ratio gelatin-silver (as AgNO₃) was 0.5. The emulsion was then ripened with 15 μmol thiosulfate and 1 μmol gold thiosulfate per mol Ag for optimal sensitivity, sensitized for the blue spectral range and stabilized.
• 4. An intermediate layer of 1200 mg gelatin, 80 mg 2,5-dioctylhydroquinone and 100 mg tricresyl phosphate.
• 5. A green-sensitive silver bromide chloride emulsion layer (99 mol% chloride) from 530 mg AgNO₃ with 750 mg gelatin, 0.625 mmol purple coupler, 118 mg α- (3-t-butyl-4-hydroxyphenoxy) -myristinic acid ester, 43 mg 2,5-dioctylhydroquinone , 343 mg dibutyl phthalate and 43 mg tricresyl phosphate (average grain size 0.4 µm, ripening: 20 µmol thiosulfate + 5 µmol gold thiosulfate per mol Ag).
• 6. An intermediate layer of 1550 mg gelatin, 285 mg of a UV absorber of the formula
  
  80 mg dioctyl hydroquinone and 650 mg tricresyl phosphate.
• 7. A red-sensitive silver bromide chloride emulsion layer (99 mol% chloride) from 400 mg AgNO₃ with 1470 mg gelatin, 0.780 mmol blue-green coupler, 285 mg dibutyl phthalate and 122 mg tricresyl phosphate (average grain size 0.3 µm, ripening: 20 µmol thiosulfate + 8 µmol gold thiosulfate per mol Ag).
• 8. A protective layer of 1200 mg of gelatin, 134 mg of a UV absorber according to the 6th layer and 240 mg of tricresyl phosphate.
• 9. A hardening layer of 400 mg gelatin and 400 mg hardening agent of the formula

Purpurkuppler:

Blaugrünkuppler:

The following connections were used as color couplers:
Yellow coupler:

Purple coupler:

Teal Coupler:

The material obtained in this way was designated Sample 1.

die Reifung der grünempfindlichen Emulsion mit 20 µmol Thiosulfat und 15 µmol Goldrhodanin und die Reifung der rotempfindlichen Emulsion mit 20 µmol Thiosulfat und 18 µmol Goldrhodanin erfolgte (Probe 2).Another material was prepared in an analogous manner, with the difference that the blue-sensitive emulsion was ripened with 15 μmol thiosulfate and 7 μmol gold compound of the formula

the green-sensitive emulsion was ripened with 20 μmol thiosulfate and 15 μmol gold rhodanine and the red-sensitive emulsion was ripened with 20 μmol thiosulfate and 18 μmol gold rhodanine (sample 2).

The processing was carried out according to the Ektacolor RA-4 process with the chemicals recommended for it (manufacturer Kodak).

The following table shows the sensitometric data from which, with somewhat improved sensitivity, almost unchanged veil, the steeper gradation in the threshold and shoulder area (G₁, G₂) emerges.

Claims (7)

1. A colour photographic silver halide material comprising at least one blue-sensitive layer with which a yellow coupler is associated, at least one green-sensitive layer with which a magenta coupler is associated and at least one red-sensitive layer with which a cyan coupler is associated, at least one layer containing a silver halide emulsion with 95 to 100 mol-% chloride which is optimally ripened with a combination of at least one sulfur ripening compound and at least one compound corresponding to the formula

in which R₁, R₂ and R₃ independently of one another represent hydrogen or alkyl and X^⊖ is an anion.

2. A colour photographic material as claimed in claim 1, in which the blue-sensitive layer or blue-sensitive layers is/are optimally ripened with a sulfur ripening compound and a gold compound according to claim 1.

3. A colour photographic material as claimed in claim 1, in which the silver halide emulsion containing 95 to 100 mol-% chloride is doped with iridium.

4. A colour photographic material as claimed in claim 1, in which all the emulsions consist of 95 to 100 mol-% chloride.

5. A colour photographic material as claimed in claim 1, in which the silver halide emulsion consisting essentially of chloride contains 0.01 to 0.5 mol-% iodide or 0.02 to 5 mol-% bromide or 0.02 to 5 mol-% thiocyanate.

6. A colour photographic material as claimed in claim 1, in which the sulfur ripening compound is used in a quantity of 0.5 to 20 µg/g Ag and the gold compound is used in a quantity of 0.5 to 20 µg/g Ag.

7. A colour photographic material as claimed in claim 1, in which thiosulfate is used as the sulfur ripening compound while a compound in which R₁, R₂ = methyl, R₃ = hydrogen and X⊖ = chloride is used as the gold compound.