DE19756737A1 - Increasing latent image stability of photographic silver chloride material containing pyrazolo-magenta coupler - Google Patents

Abstract

A colour photographic silver halide (AgX) material comprising a base and light-sensitive AgX emulsion layer(s), in which >= 95 mol.% of AgX is silver chloride (AgCl) and the emulsion contains a pyrazolo2,3-b-s-triazole magenta coupler of formula: (I) (where: R = hydrogen (H) or a group released under colour development conditions; R1 = optionally substituted alkyl; R2 = R1 or aryl; and the total number of carbon(C) atoms in R1 and R2 >= 12). The AgX emulsion specifically contains mercury (Hg).

Description

The invention relates to a silver halide color photographic material, its silver Halide emulsions consist of at least 95 mol% of AgCl and that through an improved latent image stability, especially an improved short term latent image stability.

Exposed color photographic silver halide material should be possible in processing Mostly deliver constant sensitometric results, regardless of whether between Exposure and processing are only a few seconds or many months. At Color paper reduces this time span to a few seconds to several days. This property is called latent image stability.

Color photographic silver halide materials, the silver halide emulsions of which consist of at least 95 mol% AgCl, often contain pyrazolotriazole purple couplers of the formula (I) as magenta couplers for reasons of color brilliance and color rendering.

wherein
RH or a group that is split off under the conditions of chromogenic development,
R ₁ optionally substituted alkyl,
R ₂ R ₁ or aryl,
where the sum of all carbon atoms of the radicals R ₁ and R ₂ in a coupler molecule is at least 12.

The latent image stability of such materials is not yet satisfactory. But since the The aforementioned purple couplers are fundamentally advantageous, was the object of the invention a silver halide material provided with these couplers on the base to develop high chloride silver halide emulsions, which through excellent latent image stability.

Surprisingly, this succeeds in that the silver halide has at least one Silver halide emulsion of the type mentioned contains mercury, esp is specially doped with mercury.

Mercury doping is understood to mean that mercury compounds are present Completion of the precipitation are added so that the mercury compound ever is substantially inside the silver halide grains after the time of addition and not - as with ripening - only on the surface.

The invention therefore relates to a color photographic silver halide material with a support and at least one light-sensitive silver halide emulsion layer, the silver halide of which consists of at least 95 mol% of AgCl and the contains a magenta coupler of the formula (I), characterized in that the Silver halide contains mercury.

Suitable water-soluble salts of mercury correspond to either formula (II) or (III):

Hg (X ₁ ) ₂ (II),

Hg (X ₂ ) (III),

wherein
X _{1 is} a monovalent and X _{2 is} a divalent anion, for example fluoride, chloride, bromide, iodide, nitrate, cyanide, acetate, oxalate or sulfate.

The mercury salts are preferably used as an aqueous solution.

The mercury compound is preferably used in an amount of 1.0 to 30 µmol / mol of the silver halide in question. Instant hardener or quick hardener in particular in an amount of 1 to 10% by weight, based on the gelatin to be hardened used.

The silver halide photographic material is contained in the silver halide emulsion layer containing the mercury compounds (II) and / or (III), preferably in all light-sensitive layers preferably a silver halide emulsion, which to we at least 95 mol% consists of AgCl and contains less than 4 mol% AgI, esp is particularly free of silver iodide.

The emulsions are ripened on the one hand with gold compounds and on the other with sulfur and / or selenium compounds.

The emulsions according to the invention can with acidic NH or SH compounds be stabilized in a known manner. The stabilizers are preferred after Post-ripening added and selected so that it contains the sensitizing dye, or the sensitizing dyes are not from the emulsion grains of silver chloride displace emulsion and also the bleaching of the image silver in the course of processing Do not hinder processing.

Maturation with sulfur is preferably carried out with sodium thiosulphate as a ripening agent, however, thioureas or isothiocyanates or thiophosphates can also be used as sulfur ripening agents can be used.

The ripening with selenium is preferably carried out with selenoureas which are at least tri are substituted with heterocyclic selenones that do not result in a selenolation ion can be deprotonated, or with phosphane selenides, preferably with triaryl phosphine selenides.

Ripening with gold is preferably done with gold (III) chloride or a tetrachloro aurate (III) salt, which is reduced to a gold (I) compound in the course of ripening. This can e.g. B. caused by the added bisthioether. Will the Thio ether is added together with the gold (III) salt, then the bisthioether is used as Ligand presumably reduced to a gold (I) thioether sulfoxide complex. The education of gold (I) thioether sulfoxide complexes from bisthioethers and gold (III) salts known from the literature. It can be assumed that none of the two sulfur atoms in the bisthioether is preferred.

Sulfur and / or selenium ripening on the one hand and gold ripening on the other hand can ge together or one after the other.

The emulsions can also contain other transition substances in the form of doping contain metal compounds of Group VIII of the Periodic Table, which are necessary for adjustment the desired gradation or a desired latent image behavior, or one desired development behavior largely free of reciprocity errors be added during or after the precipitation of the silver chloride. this concerns z. B. salts of rhodium (III) or of iridium (III). The emulsions can be used as Doping also contain hexacyanoferrate (II).

In addition, the emulsions can also contain palladium (II) compounds, in particular Tetrachloropalladate (II), which are said to improve long-term stability.

The emulsions can also be used to reduce haze Isothiazolone or isoselenazolone compounds, or disulfides or diselenides ent hold.

The chemical ripening by sulfur or selenium compounds and gold and the Spectral sensitization can be done separately or in one step become.

The silver halide color photographic material is preferably a copier material.

The photographic copy materials consist of a support on which at least a photosensitive silver halide emulsion layer is applied. As a carrier thin films and foils are particularly suitable. An overview of carrier materials lien and auxiliary layers applied to their front and back is in Research Disclosure 37254, Part 1 (1995), p. 285.

The color photographic copy materials usually contain at least one each red-sensitive, green-sensitive and blue-sensitive silver halide emulsions layer and optionally intermediate layers and protective layers.

Depending on the type of photographic material, these layers can be arranged differently. This is shown using the example of color negative paper:
Color photographic paper, which is generally much less light-sensitive than a color photographic film, usually has a blue-sensitive, yellow-coupling silver halide emulsion layer, a green-sensitive, purple-coupling silver halide emulsion layer and a red-sensitive, blue-green coupling silver halide emulsion layer on the support in the order given below; the yellow filter layer can be omitted.

The essential components of the photographic emulsion layers are binders, Silver halide grains and color couplers.

Information on suitable binders can be found in Research Disclosure 37254, Part 2 (1995), p. 286.

Information on suitable silver halide emulsions, their production, ripening, stabilization lization and spectral sensitization including appropriate spectral sensitization Sators can be found in Research Disclosure 37254, Part 3 (1995), p. 286 and in Research Disclosure 37038, Part XV (1995), p. 89.

Information on the color couplers can be found in Research Disclosure 37254, Part 4 (1995), p. 288 and in Research Disclosure 37038, Part 11 (1995), p. 80. Die maximum absorption of those from the couplers and the color developer oxidation pro dyestuffs formed by the product are preferably in the following ranges: ler 430 to 460 nm, magenta coupler 540 to 560 nm, cyan coupler 630 to 700 nm.

The mostly hydrophobic color couplers, but also other hydrophobic components of the Layers are usually dissolved in high-boiling organic solvents or dispersed. These solutions or dispersions are then in an aqueous Binder solution (usually gelatin solution) emulsifies and lie after the Dry the layers as fine droplets (0.05 to 0.8 µm in diameter) in the Layers ahead.

Suitable high-boiling organic solvents, methods of incorporation into the Layers of a photographic material and other methods, chemical connection Applications to introduce into photographic layers can be found in Research Disclosure 37254, part 6 (1995), p. 292.

The usually applied between layers of different spectral sensitivity ordered, non-photosensitive interlayers may contain agents which have a unwanted diffusion of developer oxidation products from a photosensitive lichen in another light-sensitive layer with different spectral sensitivity prevent bilization.

Suitable compounds (white couplers, scavengers or EOP catchers) can be found in Research Disclosure 37254, Part 7 (1995), p. 292 and in Research Disclosure 37038, Part III (1995), p. 84.

The photographic material can also contain compounds that absorb UV light, whiteners, spacers, filter _{dyes, formalin scavengers, light stabilizers, anti-oxidants, D Min} dyes, additives to improve dye, coupler and whiteness stability and to reduce color haze, plasticizers (latices) , Biocide and others.

Suitable compounds can be found in Research Disclosure 37254, Part 8 (1995), p. 292 and in Research Disclosure 37038, Parts IV, V, VI, VII, X, XI and XIII (1995), P. 84ff.

The layers of color photographic materials are usually hardened; h., that binder used, preferably gelatin, is made by suitable chemical Process networked.

Immediate or rapid hardeners are preferred, with immediate or Rapid hardeners are understood to be compounds that crosslink gelatine in such a way that that immediately after casting, at the latest a few days after casting, the hardening goes so far it is concluded that no further ones caused by the crosslinking reaction Change in the sensitometry and the swelling of the layer structure occurs. Under Swelling is the difference between the wet layer thickness and the dry layer thickness in the understood aqueous processing of the material.

Suitable instant and rapid hardener substances can be found in Research Disclosure 37254, Part 9 (1995), p. 294 and in Research Disclosure 37038, Part XII (1995), Page 86.

After imagewise exposure, color photographic materials develop their character processed according to different procedures. Details on the Ver Driving practices and the chemicals required for them are in Research Disclosure 37254, Part 10 (1995), p. 294 and in Research Disclosure 37038, Parts XVI to XXIII (1995), pp. 95 ff. Published together with exemplary materials.

Examples of couplers of the formula (I) are:

Preparation of the silver halide emulsion A: Blue sensitive emulsions Emulsion A-1

The following solutions are each made up with demineralized water:

Solution 11

1100 g water
140 g gelatin

Solution 12

1,860 g of water
360 g NaCl

Solution 13

1800 g of water
1000 g AgNO ₃

.

Solutions 12 and 13 are added simultaneously to solution 11 at 50 ° C. in the course of 300 minutes at a pAg of 7.7 while stirring vigorously. A silver chloride emulsion with an average particle diameter of 0.85 μm is obtained. The gelatin / AgNO ₃ weight ratio is 0.14. The emulsion is ultrafiltered, washed and redispersed with enough gelatin that the gelatin / AgNO ₃ weight ratio is 0.56. The emulsion is ripened at a pH of 5.3 with an optimal amount of gold (III) chloride and Na ₂ S ₂ O ₃ at a temperature of 50 ° C. After chemical ripening, the emulsion is spectrally sensitized at 50 ° C. with 1.4 g of the compound (AI) / kg Ag, stabilized with 0.5 g of the compound (AII) / kg Ag and then with 0.6 mol% KBr offset (based on silver nitrate).

Emulsion A-2: like emulsion A-1, but adding 10.5 mg HgSO ₄ to solution 11. The emulsion contains 6 μmol Hg ² / mol AgNO ₃ .

B: Green sensitive emulsions Emulsion B-1

The following solutions are each made up with demineralized water:

Solution 21

1000 g of water
140 g gelatin

Solution 22

1650 g of water
360 g NaCl
0.11 mg Na ₃

RhCl ₆

Solution 23

1600 g of water
1000 g AgNO ₃

.

Solution 22 and 23 are added simultaneously to solution 21 at 60 ° C. in the course of 105 minutes at a pAg of 7.7 while stirring vigorously. A silver chloride emulsion with an average particle diameter of 0.40 μm is obtained. The gelatin / AgNO ₃ weight ratio is 0.14. The emulsion is ultrafiltered, washed and redispersed with enough gelatin that the gelatin / AgNO ₃ weight ratio is 0.56.

The emulsion is ripened at a pH of 5.3 with an optimal amount of gold (III) chloride and Na ₂ S ₂ O ₃ at a temperature of 60 ° C. in 3 hours. After chemical ripening, the emulsion is spectrally sensitized at 50 ° C. with 2 g of the compound (BI) / kg Ag and stabilized with 1.0 g of the compound (BII) / kg Ag. Then 0.3 mol KBr / mol AgNO _{3 are} added.

Emulsion B-2: like emulsion B-1, but with the addition of 100 ml of aqueous solution containing 19.1 mg of Hg (NO ₃ ) ₂ , after a precipitation time of 50 minutes within 5 minutes. The emulsion contains an ^{intermediate zone containing Hg 2} ⁺ and a total amount of 10 µmol Hg ² ⁺ / mole AgNO ₃ .

Emulsion B-3: like emulsion B-2, but with 57.3 mg Hg (NO ₃ ) ₂ in the aqueous solution. The emulsion contains a total of 30 µmol Hg ² ⁺ / mol AgNO ₃ .

C: red sensitive emulsions Emulsion C-1 Production takes place in the same way as B-1

After chemical ripening, the emulsion is spectrally sensitized at 40 ° C. with 150 mg of the compound (CI) / kg Ag and stabilized with 2 g of the compound (CII) / kg Ag. Then 0.3 KBr / mol AgNO _{3 is} added.

Emulsion C-2: As with emulsion C-1, but with the addition of 1.5 mg Hg (CN) ₂ to solution 23. The emulsion contains a total amount of 1 μmol Hg ² / mol AgNO ₃ .

Layer structure 1

A color photographic recording material suitable for rapid processing was produced by applying the following layers in the order given to a support made of paper coated on both sides with polyethylene. The quantities given relate to 1 m ² in each case. The corresponding amounts of AgNO ₃ are given for the silver halide application.

Layer 1

(Substrate layer)
0.2 g gelatin

Layer 2

(blue sensitive layer)
blue-sensitive silver halide emulsion A-1 made from 0.40 g of AgNO ₃

With
0.96 g gelatin
0.55 g yellow coupler Y-1
0.21 g tricresyl phosphate (TKP)
0.11 g of dye stabilizer ST-1

Layer 3

(Protective layer)
1.02 g gelatin
0.05 g of 2,5-di-tert-octyl hydroquinone
0.10 g CPM
0.05 g of compound SC-1

Layer 4

(green sensitive layer)
green-sensitized silver halide emulsion B-1 made from 0.20 g of AgNO ₃

With
0.66 g gelatin
0.20 g of purple coupler M-1
0.10 g of compound SC-1
0.25 grams of Coupler Solvent K-1
0.05 g dye stabilizer ST-2

Layer 5

(Protective layer)
1.02 g gelatin
0.48 g UV absorber UV-1
0.08 g UV absorber UV-2
0.28 grams of Coupler Solvent K-2
0.025 g of 2.5 di-tert-octyl hydroquinone
0.025 g of compound SC-1
0.05 g CPM

Layer 6

(red sensitive layer)
red sensitized silver halide emulsion C-1 made from 0.29 g of AgNO ₃

With
0.85 g gelatin
0.41 g of cyan coupler C-1
0.41 g CPM

Layer 7

(Protective layer)
0.33 g gelatin
0.15 g UV absorber UV-1
0.03 g UV absorber UV-2
0.09 g Coupler Solvent K-2

Layer 8

(Protective layer)
0.92 g gelatin
0.34 g hardener H-1
The following compounds were used in sample 1:

processing

The samples were then exposed for 40 ms behind a step wedge and im Process AP 94 processed as follows:

a) Color developer - 45 s - 35 ° C

Triethanolamine 9.0 g N, N-diethylhydroxylamine 4.0 g Diethylene glycol 0.05 g 3-methyl-4-amino-N-ethyl-N-methanesulfonamidoethyl aniline sulfate 5.0 g Potassium sulfite 0.2 g Triethylene glycol 0.05 g Potassium carbonate 22 g Potassium hydroxide 0.4 g Ethylenediaminetetraacetic acid di-Na salt 2.2 g Potassium chloride 2.5 g 1,2-Dihydroxybenzene-3,4,6-trisulfonic acid trisodium salt 0.3 g fill up with water to 1000 ml; pH 10.0

b) Bleach-fix bath - 45 sec - 35 ° C

AL = L <ammonium thiosulfate 75 g Sodium hydrogen sulfite 13.5 g Ammonium acetate 2.0 g Ethylenediaminetetraacetic acid (iron ammonium salt) 57 g Ammonia 25% 9.5 g fill up with vinegar to 1000 ml; pH 5.5

c) Soaking - 2 min - 33 ° C d) drying Layer structure 2

Emulsion A1 is replaced by emulsion A2, emulsion B1 by emulsion B2 and emulsion C1 by emulsion C2, each in the same amount of AgNO ₃ .

Layer structure 3

Like layer structure 2, but with emulsion B3 instead of emulsion B2 in the same amount of AgNO ₃ .

The sensitivity difference Δlog It × 1000 for blue (ΔE _b ), green (ΔE _b ) and red light (ΔE _r ) is calculated from the sensitivity when processing 24 h after exposure minus the sensitivity when processing 60 seconds after exposure, each at a density of 0, 6 determined. The smaller the value, the better the latent image stability.

The mercury-doped silver halide emulsions of layer structures 2 and 3 show a significantly better latent image stability.

Claims (7)

1. Color photographic silver halide material having a support and at least one light-sensitive silver halide emulsion layer, the silver halide of which consists of at least 95 mol% of AgCl and which contains a magenta coupler of the formula (I)
wherein
RH or a group that is split off under the conditions of chromogenic development,
R ₁ optionally substituted alkyl,
R ₂ R ₁ or aryl,
the sum of all carbon atoms of the radicals R ₁ and R ₂ in a coupler molecule being at least 12, characterized in that the silver halide contains mercury. 2. Color photographic silver halide material according to claim 1, characterized characterized in that the silver halide is mercury-doped. 3. Color photographic silver halide material according to claim 1, characterized in that the mercury compound corresponds to one of the formulas (II) or (III)
Hg (X ₁ ) ₂ (II),
Hg (X ₂ ) (III),
wherein
X _{1 is} a monovalent and X _{2 is} a divalent anion. 4. Color photographic silver halide material according to claim 1, characterized indicates that it has been hardened with an instant hardener or a rapid hardener. 5. Color photographic silver halide material according to claim 1, characterized draws that the mercury compound in an amount of 1.0 to 30 µmol / mol of the silver halide in question is used. 6. Color photographic silver halide material according to claim 4, characterized draws that the instant hardener or quick hardener in an amount from 1 to 10% by weight, based on gelatin to be hardened, is used. 7. Color photographic silver halide material according to claim 1, characterized records that the silver halide emulsions of all silver halide emulsions at least 95 mol% of AgCl and a maximum of 4 mol% AgI exist.