EP0953164A1

EP0953164A1 - Silver-halide recording material to produce negatives with reduced fog and ultrahard-gradation

Info

Publication number: EP0953164A1
Application number: EP97923000A
Authority: EP
Inventors: Reinhold RÜGER; François VARESCON
Original assignee: Agfa Gevaert AG
Current assignee: Agfa Gevaert NV
Priority date: 1996-05-07
Filing date: 1997-05-07
Publication date: 1999-11-03
Anticipated expiration: 2017-05-07
Also published as: WO1997042545A1; DE59704335D1; DE19618194A1; EP0953164B1; US6033825A; JP2001505317A

Abstract

Photographic silver-halide materials for producing negative images with ultrahard-gradation contrast, which contain a hydrazine compound and a contrast-boosting amino compound and/or phosphonium compound, demonstrate a marked tendency to form 'black fog' which results in inadequate acutance. By adding 200 to 2500 mg per mol of silver of a polyvinyl lactam to the emulsion, the fog is inhibited and acutance is improved without reducing sensitivity. The invention can be used to produce images during reproduction in the pre-printing stage.

Description

Silver halide recording material for producing negative images of ultra-low contrast with reduced

veil

The invention relates to a silver halide photographic material for producing black and white

Negative images with ultra-partial contrast, one

Contains hydrazine compound and a contrast-enhancing amino compound. In photomechanical reproduction, often

Halftone images can be converted into halftone dot images. For this one uses silver halide materials which one in

special methods for ultra-partial contrast, d. H. developed to a maximum slope of the density curve of more than 10. For example, the lith process with low-sulfite, formaldehyde-containing hydroquinone developers is known.

Development in the presence of hydrazine compounds has recently become of particular practical importance.

This method often uses certain amino compounds to further increase the contrast. For example, EP-00 32 456-B1 claims a process in which a recording material is processed in the presence of a hydrazine compound with a hydroquinone-3-pyrazolidinone developer which contains a contrast-increasing amount of an .amino compound. However, such developers have a number of

Disadvantages on. Therefore, for some years now too

contrast-enhancing amino compounds together with

Hydrazine compounds in the photographic

Recording material incorporated. German patent application DE-A-43 10 327 describes a method for producing negative images with ultra-partial contrast, in which the development of the

Silver halide recording material in the presence of Connections are made whose molecules have at least one quaternary nitrogen atom and at least one tertiary

Have amine function.

In EP-04 73 342-A1 there is a photographic

Silver halide material described that can be developed in a developer with a pH <11 to ultra-partial contrast. The light-sensitive coating of this material contains a hydrazine compound of a certain formula and an amino or a quaternary onium compound and is adjusted to a pH of at least 5.9.

No. 4,975,354 proposes that the silver halide materials, in addition to hydrazine compounds, also have certain secondary or tertiary amino compounds, which also have at least three

Oxyethylenenneiten contained in their molecule, as

Incorporating contrast enhancers ("boosters").

EP 04 22 677 describes the use of tertiary

Amino compounds with at least three oxyethylene units in the molecule as development accelerators in developer solutions, which also act in the presence of hydrazine compounds. EP 05 39 998 claims silver halide materials which, in addition to hydrazine compounds, also contain thioether compounds with a tertiary amino group.

Other amino compounds that are incorporated with

Hydrazine compounds have a contrast-increasing effect are described in EP-A-06 63 611.

Finally, it is also known from US 4,929,535 that certain phosphonium compounds can have a contrast-increasing effect in silver halide materials which contain a hydrazine compound. A frequently observed shortcoming of the known high-contrast recording materials is a strong change in the photographic properties with prolonged storage. In particular, the veil rises. The usual measures against fog, namely the addition of antifoggants for

Emulsion and less intensive chemical ripening result in insufficient sensitivity. Moreover

the common antifoggants such as benzotriazoles, nitroindazoles and mercaptotetrazoles hinder the infectious

Development so that the contrast, especially in today's fast processing, is unsatisfactory.

Above all, high-contrast materials for high-speed processing, whose layers contain little gelatin, have a special type of veil, which is called soot or

Coal dust curtain is called. It differs from the appearance known as peppercorn veil in that the blackened areas are smaller and more numerous.

On the other hand, these areas are significantly larger than those that only consist of one developed silver halide grain

exist and the well-known emulsion veil

characterize.

Another shortcoming of such materials is the minor

Sharp contours of the stroke and

Halftone dot images, which can be partly attributed to the blurring at the edges and in the spaces between the lines and dots.

Polyvinyl lactams, especially polyvinyl pyrrolidinones, have long been used as binders for photosensitive products

Silver halide layers are known and as such are listed, for example, in Research Disclosure 365044, September 1994, Chapter II C, and 308119, December 1989, Chapter IX B. For example, DE-B-11 20 272 specifies 8 to 50 percent by weight of the dry emulsion, which may contain 30 to 70 percent by weight of silver halide, as typical amounts for use as binders. This corresponds to 21.5 to 313 g per mol

Silver bromide. Through the use of polyvinyl lactams as binders in high contrast materials, the hydrazine compounds and

contrast enhancing amino or phosphonium compounds

contain, their sensitivity is reduced to below the limit of practical usability.

The object of the invention is to propose a silver halide recording material which can be used to produce negative images with ultra-partial contrast at short intervals

Processing time is suitable, which has a high sensitivity and a low fog and the production of images with high contrast and high definition

enables, and its photographic properties do not deteriorate during storage.

These objects are achieved by a silver halide recording material according to the main claim.

Surprisingly, it was found that a

photographic silver halide material comprising at least one light-sensitive silver halide emulsion layer on a layer support, in which in the silver halide emulsion layer or in a reactive with this

Related layer both a hydrazine compound and a contrast-enhancing amino and / or

Phosphonium compound are present, excellent fog and sensitivity values with excellent sharpness and good shelf life, if the

Silver halide emulsion layer or a layer which is reactive with this, a polyvinyl lactam in an amount of 250 to 2500 mg per mol of silver halide

contains. Polyvinyl lactam is understood here to mean a vinyl polymer which consists of at least 80 percent by weight

N-vinyl lactam groups exist.

This effect was not to be expected for the person skilled in the art. The above-mentioned DE-B-11 20 272 describes namely that in the

Use of polyvinyl lactams as binders in Negative emulsions, in order to increase the opacity, an increased haze occurs, which should be reduced again by further additives.

The polyvinyl lactam to be used according to the invention is preferably a poly-N-vinyl pyrrolidinone.

The average molecular weight of the polyvinyl lactam is preferably between 6000 and 100000; the range between 15,000 and 50,000 is particularly preferred.

In a further preferred embodiment, the amount of polyvinyl lactam used is between 250 and 1000 mg per mol of silver halide; the range from 400 to 1000 mg is particularly preferred.

The hydrazine compound contained in the recording material according to the invention can be incorporated either in one or more layers of the recording material in a manner known per se. These can be layers containing the photosensitive silver halide as well as layers that are reactive with the former, i. H. which are arranged in such a way that substances can diffuse from one layer to the other if a concentration gradient is maintained by reactions. to

Incorporation can include both solutions and dispersions of the hydrazine compound in the coating solutions. Suitable hydrazine compounds are described, for example, in Research Disclosure 235 010 (November 1983),

DE-27 25 743-A1, EP-00 32 456-B1, EP-01 26 000-A2,

EP-01 38 200-A2, EP-02 03 521-A2, EP-02 17 310-A2,

EP-02 53 665-A2, EP-03 24 391-A2, EP-03 24 426-A2,

EP-03 26 443-A2, EP-03 56 898-A2, EP-04 73 342-A1,

EP-05 01 546-A1, EP-04 81 565-A, EP-05 98 315-A1,

EP-04 44 506-A. Preferred hydrazine compounds are described by the general formula (H):

B - phenyl - NHNH - L - G (H)

Here B is a ballast group, G is an activating group and L is one of the groups -CO- and -CO-CO-. "Phenyl" means a phenylene ring to which B and the hydrazine group are attached, preferably in the para position, and which may be further substituted.

Preferred ballast groups are those that are not

are electron-attracting, for example straight or

branched alkyl groups (e.g. methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-hexyl, n-octyl, t-octyl, n-decyl, n-dodecyl and similar groups), also alkoxy groups , which contain one of the abovementioned alkyl groups as alkyl, and acylamino groups, such as acetylamino, propanoylamino, butanoylamino, octanoylamino, benzoylammo, alkyl and

Arylsulfonamido and similar groups.

The groups mentioned can in turn be substituted with conventional photographic ballast groups, such as those of incorporated diffusion-resistant couplers and others

immobilized photographic additives are known. Such ballast groups typically contain at least 8

Carbon atoms and can be selected from relatively inert aliphatic or aromatic groups, for example alkyl, alkoxy, phenyl, alkylphenyl, phenoxy, alkylphenoxy, arylacyl, arylamido, alkylpyridinium-1-ylamido and similar groups.

The alkyl and alkoxy groups, including any ballast groups, preferably contain 1 to 20, the acylammo groups preferably 2 to 21 carbon atoms. However, up to 30 or more carbon atoms can be contained in these groups. Methoxyphenyl, tolyl,

ballasted butyramidophenyl, butylsulfonamido and

Toluylsulfonamido. The preferred hydrazine compounds include those whose ballast group still contains an adsorption-promoting group. Such groups promote the adsorption of the molecule on the surface of the silver halide crystals and are known per se. They typically contain at least one sulfur or nitrogen atom that can form a silver complex or otherwise have an affinity for the silver halide surface.

Preferred examples are thiourea, thiuronium,

heterocyclic thioamide and triazole groups. G is preferably hydrogen, optionally substituted alkyl

(e.g. methyl, hydroxymethyl, monofluoromethyl, pyridinomethyl, phenoxymethyl, alkoxymethyl such as methoxymethyl), if necessary

substituted aralkyl (e.g. benzyl, o-hydroxycenzyl) and optionally substituted aryl (e.g. phenyl, 3,5-dichloropnenyl,

o-methanesulfonamidophenyl, 4-methanesulfonylmethyl,

2-hydroxymethylphenyl), alkyl groups with

electron-withdrawing substituents, for example

cationic groups with quaternary nitrogen atom, such as

Pyridinium and Imidazolium, are particularly preferred. G can also be further substituted, e.g. B. with alkyl,

Aralkyl, alkenyl, alkynyl, alkoxy, aryl, substituted amino, ureido, urethane, aryloxy, sulfamoyl, carbamoyl, alkyl- or arylthio, alkyl- or arylsulfonyl, alkyl- or arylsulfinyl, hydroxy, halogen, cyan, sulfo, aryloxycarbonyl, acyl,

Alkoxycarbonyl, acyloxy, carbamide, sulfonamide, carboxyl,

Phosphamide, diacylamino, imide.

G can also be chosen so that the L-G part of the molecule is separated off with ring formation, as is the case e.g. in

EP-B-02 53 665 is described. Examples of suitable hydrazine compounds are:

The amount of the hydrazine compound is preferably between 10 ^-6 and 10 ^-2 mol per mol of silver halide.

Suitable contrast-enhancing amino compounds are

known for example from US-A-4, 914, 003, EP-A-06 18 491 and EP-A-06 63 611 and from the German patent application

19515619.6.

Amino compounds of the general formula (A) are particularly suitable wherein each of the substituents R ₁ , R ₂ and R ₃

Hydrogen atom, an alkyl group, a substituted one

Alkyl group, an alkenyl group, a substituted one

Alkenyl group, an alkynyl group, an aryl group or a substituted aryl group, but not all three are hydrogen at the same time. The substituents can also be linked together to form one or two rings and in turn can be substituted with diffusion-inhibiting (ballast) groups and / or groups which require adsorption with respect to silver halide surfaces.

Amino compounds are preferred which have at least one secondary or tertiary amino group in their molecule and moreover a group with a quaternary one

Contain nitrogen atom, a polyoxyalkylene chain, a thioether or thioketone group, a nitrile group, a sulfonylurea or urethane group or a guanidine group.

In a particularly preferred embodiment of the invention, the contrast-increasing amino compound falls under one of the general formulas (B), (C) or (D):

RR ¹ N - X - (CN) _n (B)

NC - X - NR ² - B - NR ² - X - CN (C)

RR ¹ N - X - N (CH ₂ CN) ₂ (D)

The radicals R and R ¹ can be the same or different and each can be a straight-chain or branched alkyl group having 1 to 6 carbon atoms, for example methyl, ethyl,

n-propyl, isopropyl, n-butyl, isobutyl, n-hexyl. You can also include a heterocyclic ring with 5 to 12, including the nitrogen atom and possibly another nitrogen atom, an oxygen atom or a carbonyl group

Form links, for example a piperidine, pyrrolidine, pyrroline, oxazolidine, imidazoline, morpholine, pyrazane, azepine, oxazepine or azacyclodecane ring. Each of the groups R and R ¹ can also be a benzyl group. The groups R and R ¹ and the heterocyclic rings corresponding to these groups can also be further substituted, preferably with

Hydroxyl, alkoxy, alkylthio or alkylamino groups, where the alkyl can have 1 to 6 carbon atoms. Examples of such substituents are methoxy, ethoxy, propoxy, butoxy, ethylamino, dimethylamino, butylthio.

R or R ¹ can also connect to the connecting group X with their free end to form a ring which includes the nitrogen atom of the tertiary ammo group. Such a ring can be, for example, a piperidine ring or a morpholine ring.

The divalent connecting groups X and B are preferably straight-chain, branched or cyclic alkylene groups with 1 to 20 carbon atoms, phenylene or aralkylene groups with 7 to 20 carbon atoms, or divalent chains from 1 to 20 methylene groups, in which, in addition to these, oxygen, sulfur, and amino groups , Alkene or alkyne groups or also polyoxyalkylene groups, in particular polyoxyethylene or

Polyoxypropylene groups with 1 to 50 oxyalkyl units

can be installed. An ethylene or propylene group is particularly preferred. The groups mentioned can also be further substituted, for example with alkyl, hydroxyl and further tertiary amino groups.

The connecting group X can also be trivalent and thus connect the tertiary amino group with two nitrile groups.

The groups mentioned in the previous paragraph are suitable if they contain another free valence instead of one

Hydrogen atom is present. Examples include:

The radical R ² in the general formula (B) denotes a saturated or unsaturated alkyl group, preferably having 1 to 12 carbon atoms, an aryl group, preferably having 6 to 14 carbon atoms or an aralkyl group, preferably having 7 to 15 carbon atoms. These groups can in turn

be substituted, for example with hydroxyl, amino, alkylamino and alkoxy groups, the alkyl being herein

preferably has 1 to 6 carbon atoms. If it is an alkyl group, it can also be attached to a carbon atom of group B with its end facing away from the nitrogen, forming a ring. Such a ring can be, for example, a piperidine, pyrrolidine or hexahydroazepine ring. The two radicals R ² can also together with B or with parts of B and with the two

Nitrogen atoms one or two saturated rings,

preferably with 5 or 6 links, for example

Pyrrolidine or piperidine rings.

Examples of suitable amino compounds are:

(C ₂ H ₅ ) ₂ NC ₃ H ₆ -CN HCl A-1 R ₁ , R ₂ and R ₃ each represent an alkyl, cycloalkyl, aryl,

Alkenyl or cycloalkenyl group or a heterocyclic group, where these groups can also each have substituents,

L one to the phosphorus atom via a

M-valued organic carbon bound

Group, n 1, 2 or 3, X is an n-valent anion which is also present on L

can be bound.

Examples of suitable phosphonium compounds are

O

4

The light-sensitive silver halides of the recording materials used according to the invention consist of

Silver chloride, silver bromide, silver chlorobromide,

Silver bromoiodide or silver chlorobromoiodide, where

Silver bromide and silver bromoiodide are preferred. They can be monodisperse or polydisperse, a uniform one

Have composition, but also have grains with a core-shell structure, and also be mixtures of grains of different composition and grain size distribution. They are made using a hydrophilic colloidal binder, preferably gelatin. The silver halide grains can be spherical, polyhedral or tabular. Methods for producing suitable light-sensitive silver halide emulsions are known to the person skilled in the art and are summarized, for example, in Research Disclosure 365 044, chapters I to IV (September 1994).

Preferred for those used according to the invention

Recording materials become silver halide emulsions, which are produced by controlled double jet entry and have a cubic grain shape. Emulsions in which at least 80 percent by weight of the silver halide are in cubic form are advantageous. Are particularly preferred

monodisperse emulsions, i.e. H. those where the

Coefficient of variation (quotient of standard deviation and mean) of the grain size is less than 0.30. Under

Grain size is understood to mean the edge length of a cube with the same volume as the real grain.

The grain volume of the silver halide grains in the emulsions depends on the required sensitivity and can be, for example, the cubic grains from 0.1 to 0.7 μm

Edge length. A preferred range is

between 0.15 and 0.30 μm. Precious metal salts, especially salts of rhodium or iridium, can be present in the usual amounts for controlling the photographic properties in the emulsion preparation. The emulsions are preferably chemically sensitized.

Suitable methods are sulfur, reduction and noble metal sensitization, which can also be used in combination. For the latter, for example, gold or iridium compounds can be used. The

Sensitization is preferably carried out in the presence of salts of organic thiosulfonic acids, such as p-toluene thiosulfonic acid.

The emulsions can be spectrally sensitized with conventional sensitizing dyes, for example in Research Disclosure 365 044, Chapter V (September 1994). There are sensitizers for red

(Wavelength 600 ... 690 nm) and infrared (> 690 nm) light preferred. The emulsions can also be conventional antifoggants

contain. Substituted benzotriazole, 5-nitroindazole and 1-phenyl-5-mercaptotetrazole are preferred. These agents can be used at any point in the preparation of the emulsion

be added or in an auxiliary layer of the

photographic material may be included. To improve the photographic properties, the emulsion can be an iodide, preferably a, before or after chemical ripening

Alkali iodide, in an amount of about 0.5 to 5 millimoles per mole of silver are added. The emulsions can also contain known polymer dispersions which, for example, improve the dimensional stability of the photographic material. These are generally latices of hydrophobic polymers in an aqueous matrix. Examples of suitable polymer dispersions are in Research Disclosure 176 043, Chapter IX B

(December 1978). Polymers of esters of acrylic and methacrylic acid are preferred, particularly preferably of C ₁ to C ₆ esters. The particle size of these polymer latices is preferably between 20 and 100 nm. The layers of the photographic materials can be hardened by adding a hardening agent. Hardening agents are described, for example, in Research Disclosure 365 044,

Chapter II B (September 1994). This hardener can be added to the emulsion or via an auxiliary layer

for example, an outer protective layer. Suitable hardeners are, for example, aldehydes, such as

Formaldehyde or glutaraldehyde, vinyl sulfones, s-triazines, aziridines, carbodiimides, carbamoylpyridinium compounds, mono- and bifunctional carbamoylimidazolium compounds. A preferred curing agent is hydroxydichlorotriazine. The photographic material can contain other additives which are known and customary for the production of certain properties. Such means are, for example, in Research Disclosure 365 044 (September 1994) in Chapter VI

(Brightener), IX A (coating aid), IX B

(Plasticizers and lubricants) and IX D (matting agents).

The gelatin content of the emulsions is in general

between 30 and 150 g per mole of silver; the is preferred

Range between 40 and 100 g per mol of silver.

The silver halide materials according to the invention can be used to produce black-white negative images with ultra-partial contrast. You can do this with a

suitable light source are exposed imagewise. This can be done both over the entire surface by means of a copy template, for example with an incandescent lamp or a discharge lamp, if appropriate by means of a color filter, or also by scanning with a

intensity-modulated light beam, for example from a gas, solid or semiconductor laser. On

preferred method uses a HeNe laser or a

Semiconductor laser with emission in the red spectral range.

Processing of the exposed material to form the image preferably comprises treatment with an aqueous developing bath, with an aqueous fixing bath, washing and drying.

Processing is preferred as a rapid process with a development time of at most 30 s and corresponding

adapted developer temperature, for example 32 ° C and above. In order to achieve a high development speed and to keep the amount of waste solution low by means of a low regeneration rate, developer solutions with a high content of are preferably used

Developer substance, for example more than 25 g per liter. The developer solutions preferably contain one

Dihydroxybenzene developer substance, for example

Hydroquinone, pyrocatechol, methylhydroquinone or

Chlorohydrochmon, and an antioxidant, preferably an alkali sulfite in a concentration of less than 0.3 mol per liter. Solutions with pH values from 9 to at most 11, particularly preferably from 10 to 10.5, are preferably used. Such developer solutions are also very durable in use. Developer solutions with a can also be used

Ascorbic acid type developer, for example

L-ascorbic acid, D-ascorbic acid, L-erythroascorbic acid, 6-deoxy-L-ascorbic acid, imino-L-erythroascorcic acid or sugar derivatives of these acids. Are also suitable

Development solutions that both developer substances from

Dihyoroxyoenzol type as well as those of the ascorbic acid type included.

The developer solutions preferably contain known solutions

super-additive auxiliary developer substances,

for example N-methyl-p-aminophenol or

1-phenylpyrazolidinone-3 or derivatives of these compounds.

Developers containing antifoggants from the group of benzotrazoles are also preferred. Such

Antifoggants are, for example, benzotriazole,

5-chloroenztriazole, 5-bromobenzotriazole, 5-methylbenztriazole, 5-nitrobenztriazole, 5-benzoylaminobenztriazole,

1-hydroxymethylbenztriazole, 6-cyanobenztriazole.

The recording materials according to the invention are distinguished by low Schieier values and excellent

Storage stability. This applies above all to a slight soot veil. On the other hand, the inventive

Materials also have a high gradation in the foot and

Middle area. Due to the low veil and the high

The gradation of the foot can be fully exploited and the optimal grid size can be achieved because the

Sensitivity to stray light is reduced. The invention can be used to produce black and white

Negative images with ultra-partial contrast, especially when reproducing in prepress for black and white and multi-color printing, are used. In the following exemplary embodiment, the amounts of the emulsion additives, unless otherwise noted, relate to

1 mol of silver halide.

A cubic silver bromoiodide emulsion with grains with an edge length of 0.18 μm is produced by pAg-controlled double jet precipitation. The iodide content is 2 mol% based on

Silver. This emulsion is flocked, washed and washed with

10 ^-5 moles of hexachloroplatinic acid, 8 mg of potassium thiotosylate, 6 mg of benzenesulfinic acid, 0.4 millimoles of thiosulfate and 0.1 millimoles of tetrachlorocrogoldic acid chemically matured. At the end of chemical ripening, 400 mg of sodium sulfite and 5 millimoles

Potassium iodide, 300 mg 7-hydroxy-1-methyltriazaindoline, 200 mg 5-nitroindazole, 0.15 millimole 1-pyridiniumacetyl-2- (4-benzyloxyphenyl) hydrazine bromide (compound H-9) and 600 mg 4,4'-trimethylene bis-piperidinopropionitrile (Compound A-4), a red sensitizer (KF 641, manufacturer

Riedel-de Haën), sodium tetradecyl sulfonate as

Coating aids, and in each case parts of the emulsion thus obtained polyvinylpyrrolidinone MW 30,000 (PVP) in

various amounts added according to Table 1.

By applying the emulsions together with two gelatin protective layers (altogether 0.9 g gelatin per m ² ) to a polyethylene terephthalate base provided with an antistatic and anticurl layer on the back, red-sensitive ones became

Scanner films made. The silver coating was 3.5 g per m ² . The protective layers also contained hydroquinone,

Polyethylene oxide 20000, 500 mg / m ² colloidal silica and a polyolefin oxidate according to DE 43 11 888. The layers were coated with 1 millimole of hydroxydichlorotriazine, sodium salt, and

0.1 millimoles of bis-dimethylcarbamoylimidazolium chloride, each per gram of gelatin, hardened. Samples of the films were then exposed to a flash (10 ^-3 s) through a red filter and a density wedge and processed in a developer of the composition given below in an automatic processor (DuPont ECP 55) with 30 s development time at 35 ° C. A commercially available fixing bath was used. On the processed samples, foot gradations Gl between the density values 0.1 and 0.4, gradation G2 between the densities 0.4 and 3.5,

Veil Dmin, maximum density Dmax and sensitivity S determined in relative arithmetic units both 3 days and 3 months after production. The samples were stored at 22 ° C and 55% relative humidity.

By exposing halftone dots with a commercially available scanning exposure device (Linotronic 300 from Hell) and developing as above, halftone elements were produced to assess the sharpness of the contours of the pixels. These were assessed visually using an 80x magnifying glass. The

Results are summarized in Table 1. The measurement results after 3 months of storage of the material are in brackets.

Adjust water to 1 liter, pH to 10.5 at 22 ° C. l

Claims

claims

1. Including silver halogenic photographic material

at least one light-sensitive silver halide emulsion layer on a layer support, both in the silver halide emulsion layer or in a layer which is reactive with it

Hydrazine compound and a contrast-increasing amino and / or phosphonium compound are present,

characterized in that

there is also a vinyl polymer in the silver halide emulsion layer or in a layer which is in a reactive relationship therewith which comprises at least 80

Weight percent consists of N-vinyl lactam groups, in an amount of 250 to 2500 mg per mol of silver halide.

2. Material according to claim 1,

characterized in that

the polyvinyl lactam in an amount of 250 to 1000, preferably 400 to 1000 mg per mol of silver halide in

Silver halide material is present.

3. Material according to claim 1 or 2,

characterized in that

the polyvinyl lactam is a polyvinyl pyrrolidinone, preferably with a molecular weight of 6000 to 100000

4. Material according to one of claims 1 to 3,

characterized in that

the hydrazine compound has the general formula

B - phenyl - NHNH - L - G, where B is a ballast group, G is an activating group

Group, -phenyl- is an optionally substituted phenylene radical and L is CO or CO-CO.

5. Material according to one of claims 1 to 4,

characterized in that

the contrast-enhancing amino compound under the

general formula (A) falls

wherein each of the substituents R ₁ , R ₂ and R ₃

Hydrogen atom, an alkyl group, a substituted alkyl group, an alkenyl group, a substituted one

Alkenyl group, an alkynyl group, an aryl group or a substituted aryl group, the substituents can be linked to one or two rings, but not all three are simultaneously hydrogen.

6. Material according to one of claims 1 to 5,

characterized in that

the contrast-increasing amino compound under one of the general formulas

falls, in which R, R ^{1 are} identical or different, each one optionally

substituted alkyl group with 1 to 6

Carbon atoms or an optionally substituted Benzyl group, or R and R ¹ together with the nitrogen atom and possibly another

Oxygen or nitrogen atom is a five- to eight-membered ring, R ^{2 is} a saturated or unsaturated alkyl group or an aryl group, these groups can be further substituted, or an alkyl group can be substituted with nitrogen

end facing away from a group B carbon atom to form a ring,

X a divalent or trivalent connecting

Group,

B is a divalent connecting group, n 1 or 2.

7. Material according to one of claims 1 to 6,

characterized in that

the phosphonium compound has the general formula (P)

in what mean

R ₁ , R ₂ and R _{3 are} each an alkyl. Cycloalkyl. Aryl,

Alkenyl or cycloalkenyl group or a heterocyclic group, these

Groups can also each have a substituent. L one to the phosphorus atom via a

Carbon-bound m-valent organic group, n 1, 2 or 3, X is an n-valent anion, which can also be bonded to L.

8. Material according to one of claims 1 to 7,

characterized in that

the silver halide emulsion is a silver bromide or

Silver iodobromide emulsion is.

9. Material according to one of claims 1 to 8,

characterized in that

the silver halide emulsion is sensitized to red and / or infrared light.

10. Use of a material according to one of the claims

1 to 9 for the generation of black and white negative images with ultra-partial contrast.