DE19603243A1 - Improving stability and reproducibility in photographic material made using immediately-acting hardeners - Google Patents

Abstract

The novel feature in production of a photographic material using an immediately-acting hardener is that a compound of one of the transition metals Cu, Fe, Co, Ni, Ru, Rh, Pd, Au, Os, Ir or Pt is added (i) to the Ag halide emulsion after the finish of chemical ripening ; or (ii) to the casting solution used to form a non-light-sensitive intermediate or protective layer.

Description

The invention relates to a method for producing a photographic Auf drawing material cured with an instant hardener and used in the United same with conventional materials has improved stability.

For the production of photographic materials is a hardening of the layers required. For curing, the following methods are known:

The conventional hardening with additives, eg. B. Triacrylformal, the Gießlö be admixed before applying for the train. The hardening of the ange wear Schichtverbandes is only after several weeks storage time of the train completed. Disadvantages are the large storage costs and the uneven Quality caused by different storage conditions caused different hardening.

The fast curing process also uses additives, e.g. As vinyl sulfones, the be added to the casting solutions. The hardening of the coating is after completed a few hours, which is basically beneficial, but it will be very high demands on the drying process and on the residual moisture of the Products, otherwise a deterioration of product quality by After hardening begins.

Compared to these methods, the instant hardening process offers a whole series of advantages. DE-A-22 25 230, DE-A-24 39 551 and EP-A-267 523 described instant hardeners have the advantage that the curing directly after the pouring is finished, so that no further by the crosslinking reaction Conditional change in sensitometry and swelling of the composite occurs. Therefore, the photographic properties of the material immediately after the Be determined at the end of production.

The application of the instant softening agents described is also with Nach shared, namely a reduced stability of the cured with them photographic materials. In particular, the storage at elevated temperature in closed can, as is usually the case in tropical regions,  causes significant changes in the sensito for immediately cured materials metric properties.

Furthermore, the stability of photographic materials is very dependent on the Production conditions, in particular of the drying conditions after the Apply the instant hardener. This leads to a bad reproduction stability level and is particularly problematic when a photo graphic material is not always produced under exactly the same conditions is, for. B. when using different casting machines.

The invention is therefore based on the object, a photographic recording provide material that can be cured with an instant hardener and not the previously associated disadvantages in terms of stability having.

It has now surprisingly been found that this object can be achieved when one in the production of a photographic material a Compound of a certain transition metal admits.

The invention therefore provides a process for the preparation of a photogra fishing recording material with a carrier on the at least one photosensitive silver halide emulsion layer and at least one light sensitive intermediate or protective layer is applied, with the steps

• a) preparation of the photographic emulsion,
• b) pouring of the carrier and
• c) drying the material,

characterized in that a compound of a transition metal from the Cu, Fe, Co, Ni, Ru, Rh, Pd, Au, Os, Ir and Pt photosensitive Silver halide emulsion after completion of chemical ripening or Casting added to a light-insensitive intermediate or protective layer and an instant hardener is used to cure the material.

The inventive method of adding the transition metal compounds is new and differs from the use of these compounds in chemi ripening during the preparation of the photographic emulsion. It was  namely found that the addition of the total amount of Übergangsmetallver Already during the chemical ripening only the photographic veil increases and the stability of the material deteriorates.

For the production of chemically and spectrally sensitized photographic silver halo genidemulsionen, the following, consisting of 4 steps, Ver enforced by driving:

• 1. the precipitation of highly dispersed, colloid-protected, in water almost un soluble silver halides by double reaction between aqueous Alkali or ammonium halide solutions and aqueous silver or sil Berdiamminnitratlösungen in the presence of gelatin as a protective colloid, wherein the precipitate is to produce desired dispersities can join a so-called physical maturation,
• 2. the removal of the precipitate and physical ripening in solution remaining agents, such as nitrate ions, alkali ions, ammonium ions after the so-called flock washing process, after the noodle Waschver drive or by ultrafiltration,
• 3. Ripening, also called chemical ripening, in the course of which the chemical sensitization of the emulsions is effected by trace amounts of sulfur or selenium compounds, rhodanoaurates (I), Rhodano palladate (II). For this, the emulsion is 30 to 360 min. long at 36 ° C to 60 ° C digested. In the course of this digestion, the light sensitivity of the emulsions increases greatly. The fog remains almost constantly low until it reaches the maximum sensitivity, but then increases more or less strongly. The chemical ripening must, therefore, immediately after reaching the point in time t _opt, which is the one who time at which the optimal sensitometric characteristics of the emulsions are achieved, be canceled. The termination of the chemical ripening is brought about by cooling the emulsion and, if appropriate, by adding stabilizers. Stabilized emulsions are stored for a few days to weeks in refrigerated rooms for further processing to the photosensitive layers of the photographic imaging materials. In the course of this operation, ripening centers have formed on the silver halide microcrystals which, in particular depending on their dispersity, may preferably serve as electron donors or electron acceptors in the processes occurring between light absorption and formation of latent image nuclei,
• 4. Addition of sensitizer dyes to the previously remelted and for the addition of photosensitive imaging materials conditioned chemically matured emulsions. This will be the chemically ripened emulsions also for light of those wavelengths sensitized, those of the introduced sensitizer dyes be absorbed. The efficiency of this spectral sensitization depends now, to a decisive extent, that as many excited as possible light Dye molecules can be reduced and the resulting Dye radicals their surplus electrons as lossless as possible developable latent image germs.

When added to a photosensitive silver halide emulsion layer the transition metal compounds of the photographic emulsion after completion added to the chemical ripening. Preferably, the transition metals Compounds after the spectral sensitization in the production of the casting finished emulsion added.

The transition metal compounds of the invention are lichtempfindli emulsion after completion of the chemical ripening or the casting solution light-insensitive intermediate or protective layer in an amount of 0.01 to 100 μmol / m² added. Preferably, 0.1 to 10 μmol / m² are added.

Particularly effective compounds of the transition metals Pd and Au proved. Of these, K₂PdCl₄ and HAuCl₄ can be particularly good for the use purpose of the invention.

As an instant hardening agent in the process according to the invention, the in DE-A- 22 25 230, DE-A-24 39 551 and EP-A-267 523 be set.

Preferred instant hardeners are the carbamoylpyridinium compounds of Formula I

wherein
R¹ and R² are the same or different, each being an alkyl group having 1 to 3 carbon atoms or an aryl or aralkyl group optionally substituted with an alkyl group having 1 or 2 carbon atoms or a halogen atom, or together to complete any one having an alkyl group with 1 or 2 atoms or atoms required with a halogen atom substituted piperidine or morpholine ring,
R³ is a hydrogen atom or an alkyl group having 1 or 2 carbon atoms and
n 0 or 2
mean.

Examples of instant hardeners of the formula I are:

The compounds of formula I become the photographic layers to be cured expediently immediately before casting, preferably in the form of aq ger or alcoholic solutions added. The addition is just before the casting therefore necessary because the compounds with gelatin or the other in the Photography commonly used proteins react very quickly. After this one has added the compounds, the casting solutions within less Minutes to be shed. The speed with which the curing reaction depends primarily on the concentration of proteins in the casting solution from.  

The preparation of the instant hardeners of the formula I is known from DE-A-24 39 551 known.

The inventive method allows the production of a photographic Recording material that can be processed immediately after the pouring and nevertheless a high level of stability, especially when stored at elevated temperatures Temperature in closed wall box, owns.

Another part of the invention therefore relates to the method according to Claim 1 available photographic recording material.

Examples of producible by the process according to the invention farbfotogra Fish materials are color negative films, color reversal films, color positive films, color photographic paper, color reversal photographic paper, color sensitive mate materials for the dye diffusion transfer process or the silver dye bleaching process Preferably, by the process according to the invention Farbnegativfil Made me.

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

Cellulosetriacetate (CTA) and polyethylene glycol are preferably suitable as carriers col-2,6-naphthalate (PEN).

The color photographic materials usually contain at least one red each 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 may be different be arranged. This is illustrated for the main products:

Photographic films such as color negative films and color reversal films exhibit the sequence indicated below on the carrier 2 or 3 rotempfind pale cyan silver halide emulsion layers, 2 or 3 greenemp  sensitive, purple-coupling silver halide emulsion layers and 2 or 3 blue sensitive, yellow coupling silver halide emulsion layers. The layers same spectral sensitivity differ in their photographic Emp sensitivity, with the less sensitive sublayers usually closer are arranged to the carrier than the higher sensitive sub-layers.

Between the green-sensitive and blue-sensitive layers is more common a yellow filter layer attached, the blue light prevents it, in the to reach underlying layers.

The possibilities of different layer arrangements and their off effects on the photographic properties are described in J. Inf. Rec. Mats., 1994, Vol. 22, pages 183-193.

Color photographic paper, which is generally much less sensitive to light as a color photographic film, has the order given below usually a blue-sensitive, yellow-coupling silver halo on the support genisemulsion layer, a green sensitive, purplish coupling silver halide emulsion layer and a red-sensitive, cyan silver halide emulsion layer on; the yellow filter layer can be omitted.

Deviations from the number and arrangement of the photosensitive layers can to achieve certain results. For example, you can all highly sensitive layers to a layer package and all low-sensitivity layers to another layer package in a photographic film summarized to increase the sensitivity (DE 25 30 645).

Essential constituents 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 preparation, ripening, Stabilization and spectral sensitization including appropriate spectral sensitizers can be found in Research Disclosure 37254, Part 3 (1995), p. 286 and in Research Disclosure 37038, Part XV (1995), p. 89.  

Photographic materials with camera sensitivity usually include Sil Berbromidiodidemulsionen, which may also contain small amounts of silver chloride can contain. Photographic copying materials contain either silver chloride bromide emulsions containing up to 80 mol% AgBr or silver chloride bromide emulsions with over 95 mol% AgCl.

For color couplers see Research Disclosure 37254, part 4 (1995), p. 288 and Research Disclosure 37038, Part II (1995), p. 80. The maximum absorption from the couplers and the color developer oxidation product formed dyes is preferably in the following areas: Yellow coupler 430 to 460 nm, magenta coupler 540 to 560 nm, cyan coupler 630 up to 700 nm.

In color photographic films, to improve sensitivity, Graininess, sharpness and color separation are often used in the compounds Reaction with the developer oxidation product release compounds, the foto are graphically effective, z. B. DIR couplers which are a development inhibitor columns.

Information on such compounds, in particular couplers, can be found in Research Disclosure 37254, Part 5 (1995), p. 290 and in Research Disclosure 37038, Part XIV (1995), p. 86.

Most hydrophobic color couplers, but also other hydrophobic components the layers are usually in high boiling organic solvents dissolved or dispersed. These solutions or dispersions are then in a aqueous binder solution (usually gelatin solution) emulsified and are after drying the layers as fine droplets (0.05 to 0.8 microns through knife) in the layers.

Suitable high-boiling organic solvents, methods for incorporation into the layers of a photographic material and other methods, chemical To introduce compounds into photographic layers can be found in Research Disclosure 37254, Part 6 (1995), p. 292.

The usually between layers of different spectral sensitivity ordered non-photosensitive intermediate layers may contain agents  the unwanted diffusion of developer oxidation products from a light sensitive in another photosensitive layer with different spek prevent trol sensitization.

Suitable compounds (white couplers, scavengers or EOP scavengers) 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 may also contain UV light absorbing compounds, white toners, spacers, filter dyes, formalin scavengers, light stabilizers, antioxidants, D _min dyes, additives for improving the dye, coupler and white stability and for reducing the color fog, plasticizers (lattices), Biocide and other included.

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

After imagewise exposure, color photographic materials become their character ter accordingly processed according to different methods. Details of the Procedures and required chemicals are in Research Disclosure 37254, Part 10 (1995), p. 294 and Research Disclosure 37038, parts XVI to XXIII (1995), p. 95 et seq., Together with exemplary materials.

example

A color photographic recording material for color negative color development was prepared (layer structure no. 1) by placing on a transparent layer Cellulose triacetate the following layers in the specified rows sequence were applied.

Quantities are given in g / m², in the case of silver halide emulsions the silver nitrate used is used as a basis. The emulsions continue to be due to the halide content as well as the volume center of gravity (VSP - Volume center: 50% value of the cumulative frequency of the volume distribution the silver halide particle). All photosensitive emulsions used are with Thiosulfate / Gold Rhodane matured to optimum sensitivity. The assignment of a Substance to a function serves only the coarse characterization, it can also cause other effects.

Layer 1 (Antihalo Layer) black colloidal silver 0.28 gelatin 1.30

Layer 2 (low-sensitivity, red-sensitized layer) Silver bromide iodide emulsion with 9 mol% iodide (VSP = 0.42) 0.85 Maturation with Na₂S₂O₃ (25 .mu.mol / mol AgNO₃), HAuCl₄ (6.0 .mu.mol / mol AgNO₃), KSCN (800 .mu.mol / mol AgNO₃) @ Teal coupler C-1 0.33 DIR coupler D-1 0.01 Mask coupler MS-1 0.03 Mask coupler MS-2 0.01 Tricresyl phosphate (TKP) 0.34 gelatin 0.68

Layer 3 (medium-sensitive, red-sensitized layer) Silver bromide iodide emulsion with 6 mol% iodide (VSP = 0.70) 1.10 Maturation with Na₂S₂O₃ (16 .mu.mol / mol AgNO₃), HAuCl₄ (3.2 .mu.mol / mol AgNO₃), KSCN (500 .mu.mol / mol AgNO₃) @ Teal coupler C-1 0.12 DIR coupler D-1 4 × 10 ^-3 Mask coupler MS-1 0.06 Mask coupler MS-2 2 × 10 ^-2 CPM 0.17 gelatin 0.62

Layer 4 (highly sensitive, red-sensitized layer) 7 mol% iodide silver bromide iodide emulsion (VSP = 1.25) 1.65 Maturation with Na₂S₂O₃ (8 mol / mol AgNO₃), HAuCl₄ (1.4 mol / mol AgNO₃), KSCN (200 mol / mol AgNO₃) @ Teal coupler C-2 0.10 DIR coupler D-2 0.04 CPM 0.07 gelatin 0.75

Layer 5 (intermediate layer) Scavenger S-1 0.06 CPM 0.03 gelatin 0.75

Layer 6 (low-sensitivity, green-sensitized layer) Silver bromide iodide emulsion with 9 mol% iodide (VSP = 0.42) 0.72 Maturation with Na₂S₂O₃ (25 .mu.mol / mol AgNO₃), HAuCl₄ (6.0 .mu.mol / mol AgNO₃), KSCN (800 .mu.mol / mol AgNO₃) @ Purple coupler M-1 0.28 DIR coupler D-1 4 × 10 ^-3 DIR coupler D-2 1 × 10 ^-3 Mask coupler MS-3 0.03 CPM 0.20 gelatin 0.61

Layer 7 (medium-sensitive, green-sensitized layer) Silver bromide iodide emulsion with 5 mol% iodide (VSP = 0.60) 1.51 Maturation with Na₂S₂O₃ (16 .mu.mol / mol AgNO₃), HAuCl₄ (3.2 .mu.mol / mol AgNO₃), KSCN (500 .mu.mol / mol AgNO₃) @ Purple coupler M-1 0.26 DIR coupler D-1 6 × 10 ^-3 DIR coupler D-2 3 × 10 ^-3 Mask coupler MS-3 0.06 CPM 0.22 gelatin 0.91

Layer 8 (highly sensitive, green sensitized layer) Silver Bromide Diiodide Emulsion with 6 mol% iodide (VSP = 1.10) 1.74 Maturation with Na₂S₂O₃ (8 mol / mol AgNO₃), HAuCl₄ (1.4 mol / mol AgNO₃), KSCN (200 mol / mol AgNO₃) @ Purple coupler M-1 0.08 Mask coupler MS-4 0.04 Scavenger S-1 0.01 CPM 0.08 gelatin 0.81

Layer 9 (yellow filter layer) Dye F-1 0.07 gelatin 1.33

Layer 10 (low-sensitivity, blue-sensitized layer) Silver bromide iodide emulsion with 6 mol% iodide (VSP = 0.70) 0.30 Maturation with Na₂S₂O₃ (25 .mu.mol / mol AgNO₃), HAuCl₄ (6.0 .mu.mol / mol AgNO₃), KSCN (800 .mu.mol / mol AgNO₃) @ Yellow coupler Y-1 0.30 DIR coupler D-1 0.02 CPM 0.17 gelatin 0.51

Layer 11 (medium-sensitive, blue-sensitized layer) Silver bromide iodide emulsion with 9 mol% iodide (VSP = 0.90) 0.34 Maturation with Na₂S₂O₃ (16 .mu.mol / mol AgNO₃), HAuCl₄ (3.2 .mu.mol / mol AgNO₃), KSCN (500 .mu.mol / mol AgNO₃) @ Yellow coupler Y-1 0.49 DIR coupler D-1 6 × 10 ^-3 CPM 0.25 gelatin 0.66

Layer 12 (highly sensitive, blue-sensitized layer) Silver bromide iodide emulsion with 7 mol% iodide (VSP = 1.20) 1.50 Maturation with Na₂S₂O₃ (8 mol / mol AgNO₃), HAuCl₄ (1.4 mol / mol AgNO₃), KSCN (200 mol / mol AgNO₃) @ Yellow coupler Y-1 0.24 DIR coupler D-2 0.04 CPM 0.26 gelatin 0.92

Layer 13 (protective layer) Silver bromide iodide emulsion with 4 mol% iodide (VSP = 0.05) 0.25 UV absorber UV-1 0.30 UV absorber UV-2 0.11 gelatin 1.40

Layer 14 (protective layer) Hardener H-15 0.80 gelatin 0.24

The total order of silver (AgNO₃) of the photographic material is 10.24 g / m², the total gelatin 12.05 g / m². The thickness of the layer carrier is 120 microns.

Variants of the described material (layer structures Nos. 2 to 26) were like produced in the following table. The specified in the table Amounts of transition metal compounds were added to the casting solutions of Schich after the spectral sensitization of the emulsions.

The different materials were either immediately after the pouring (in the case the immediately cured materials, hardeners H-9 and H-15) or 4 days after the pouring (in the case of the fast-hardened materials, hardeners H-V) processed. They were there

• a) Illuminated behind a graduated gray wedge with daylight and afterwards the process described in "The British J. of Photography" 1974, p. 597 processed and the sensitivity after densitometric measurement behind blue filter (gb), green filter (pp) and red filter (bg) each at density 0.2 determined over fog in relative DIN units  
• b) cut into strips 135 cm long and 3.6 cm wide and in film Assembled cartridges. After matching these patronized film materials in a climate of 60% R.F. at 23 ° C (2 days) was after Insert in a standard polyethylene liner for 3 days Heated to 60 ° C. Thereafter was treated as under a) and the difference of Sensitivity to a) determined.

The results obtained are shown in the following table.

As is clear from the examples listed, the invention improves proper addition of transition metal compounds the stability of the photographic Material. At the same time one of the casting machine and the film underlay un reached a dependent level. All materials according to the invention correspond to the Curing kinetics A (see figure).

Illustration

Substances used in the example:

Claims (8)

A process for the preparation of a photographic material comprising a support having thereon at least one light-sensitive silver halide emulsion layer and at least one light-insensitive intermediate or protective layer, comprising the steps

• a) preparation of the photographic emulsion,
• b) pouring of the carrier and
• c) drying the material,

characterized in that a compound of a Cu, Fe, Co, Ni, Ru, Rh, Pd, Au, Os, Ir and Pt transition metal is added to a light-sensitive silver halide emulsion after completion of the chemical ripening or the casting solution of a light insensitive intermediate or protective layer and an instant hardener is used to cure the material. 2. The method according to claim 1, characterized in that the transition metal compound is added in an amount of 0.01 to 100 .mu.mol / m² becomes. 3. The method according to claim 1, characterized in that it is in the Transition metal compound is a compound of Pd or Au. 4. The method according to claim 3, characterized in that it is in the Transition metal compound to K₂PdCl₄ or HAuCl₄ is. 5. The method according to claim 1, characterized in that it is in the instant hardening agent to a carbamoylpyridinium compound of the formula I. wherein
R¹ and R² are the same or different, each being an alkyl group having 1 to 3 carbon atoms or an aryl or aralkyl group optionally substituted with an alkyl group having 1 or 2 carbon atoms or a halogen atom, or together to complete an optionally with an alkyl group 1 or 2 carbon atoms or atoms required with a halogen atom substituted piperidine or morpholine ring,
R³ is a hydrogen atom or an alkyl group having 1 or 2 carbon atoms and
n 0 or 2
mean, act. 6. The method according to claim 1, characterized in that the transition metal compound of a photosensitive silver halide emulsion according to the spectral sensitization in the production of pourable Emul added. 7. Photographic recording material obtainable by the method according to Claim 1.