DE2242761A1 - PHOTOGRAPHIC MATERIAL - Google Patents

Description

2242751

Photographic material

The invention relates to a photographic material having a photobleachable dye.

It is known that certain compounds substituted by nitro radicals are subject to photolytically induced reactions. For example, from the book "Photo Chemistry" by JG Calvert and JN Pitts Jr., Verlag J. Wiley and Sons, New York, 1966, page 477, it is known that o-nitrobenzaldehyde can be converted into o-nitrobenzoic acid by a photo-induced conversion and that further o-nitrostilbenes can form various reaction products due to photo-induced reactions. It is also known from the "Canadian Journal of Chemistry" , £ 4, page 1041 (Ί968) that nitrobenzene can be reacted with an alkene by a photo-induced reaction to form an unstable cyclic reaction product. Finally, the photolytic rearrangement of nitro-substituted biphenyls is known from the journal "Journal of American Chemical Society" _t JTJ, page 1400 (1965).

The research results available so far in this area have so far only been of theoretical interest. A practical one Application of such photolytically induced reactions of nitro-substituted compounds in the field of photographic is not yet known.

It is also known to use dyes for the production of antihalation layers of photographic materials. For example, it is known from US Pat. No. 2,527,583 to use dyes in intermediate layers and back layers of photographic recording materials to prevent the formation of halos. The use of dyes in special antihalation layers requires a special operation in the production of the photographic recording materials. When special antihalation layers are arranged, there is also the problem of removing the dye. Closing

309810/1035

borrowed, the absorption characteristics of the dye after it has performed its task to be observed.

According to a known 'method, the antihalation dye is in a layer arranged on the side of a support which is opposite the side of the support which the image-recording Has layers. The layer is then removed during the development process. This method requires a special developing device only for the removal of the antihalation layer, with the additional possibility of that the film material during the removal of the antihalation layer damaged, for example by traces of abrasion. According to another known method, weiriv.ecir.sensitive licensing protective dyes are used used by the action of heat may be destroyed or have such absorption characteristics that are easily changed by heating the photographic Let the material change to a certain temperature in such a way that it no longer interferes. The disadvantage of this method is that When the material is heated, also thermally sensitive image dyes can be changed. Also can dimensional stability the image obtained can be adversely affected by this method.

It is also known to use nitrostyryl dyes as desensitizing agents Use dyes for direct positive emulsions. These dyes contain a basic nucleus for cyanine dyes usual type in which the nitrogen atom is in quaternary Form is present, the basic core nit via a vinyl chain an even number of carbon atoms to a nitro-substituted one Aryl radical is bonded (see, for example, the US patents 2 541 472, 3 023 102 and 2 953 561). It is also known from US Pat. No. 2,541,472 that nitrobenzylidene rhodanine is known can be used for the production of direct-positive emulsions. The known nitrostyryl dyes do not iron or only very slight fading properties and that

309810 / 1035- bad original

Xitrobenzylidenrhodanin has a broad absorption band in Range of the spectrum below 400 nm.

Surprisingly, it has now been found that certain nitro-substituted Arylidene dyes, especially benzylidene dyes with a heterocyclic basic core, extremely effective photobleachable dyes and at the same time valuable Are sensitizing dyes. In these o-kitro-substituted Arylidene dyes are those in which the o-nitro-aryl radical is attached via a methine chain a basic heterocyclic radical with one as an electron donor acting atom is bound that the number of carbon

the
Substance atoms that connect / act as electron donor atoms with the aryl radical, corresponds to a straight number.

It has been found that these o-nitro-substituted arylidene dyes, in particular benzylidene dyes, can be used in many ways for the production of a wide variety of photographic materials due to their bleachable properties. So xxKhxaii leave them for the production \ ^r on imaging recording materials use, where they are the image-forming substances. Furthermore, they can advantageously be used as antihalation dyes, since they can be removed from the photographic material to be protected without rubbing off an antihalation layer or without heating the material. Finally, the o-? Jitro-substituted dyes described can also be used excellently as desensitizing dyes for photographic silver halide emulsions.

The invention thus provides a photographic material with a photobleachable dye, which is characterized is that> e: 5 is an o-nitro-substituted dye as the photobleachable dye Arylidene dye, the o-nitroaryl radical of which such via an '-ic think et te of a basic heterocyclic residue

3 0 9 8 10/1035

with an atom acting as an electron donor is bonded that the number of carbon atoms that acts as an electron donor acting atom connect with the aryl radical, corresponds to an even number, contains.

The atom acting as an electron donor preferably consists of a nitrogen, oxygen, sulfur or selenium atom.

As particularly advantageous o-nitro-substituted arylidene dyes have been found in which the o-nitro-substituted aryl radical by an acyclic methine chain with a odd number of methine groups attached to a 5- or 6-membered basic nitrogen containing heterocyclic nucleus is, it being possible for one or more further carbocyclic or heterocyclic rings to be fused onto this core.

A photographic material according to the invention with at least one of the dyes described can thus consist, for example, of a photosensitive recording material which is used for Can be used to produce photographic images by imagewise exposure to electromagnetic radiation, against which the o-nitro-substituted dyes contained in the material are sensitive.

The photographic material of the invention can also consist for example of a light-sensitive photographic recording material which one or more of the described Has dyes for the purpose of preventing the formation of antihalation layers. Here, according to the invention Arylidene dyes used, for example, be contained in the support. On this support can then one or more light-sensitive silver halide photographic emulsions be applied, 'which can be exposed and developed in a conventional manner.

309810/1035

As particularly advantageous o-nitro-substituted arylidene dyes those of the following structural formula have been found

: "" ^ζ τ "Ί

I. R ₁ -Ä-fr-L = L- ^ rC = CH - ^ - CH = CHHh: - C

I Hl K * ^^ fc.

- NO

where mean:

k = 0 or 1;

m = 0 or 1; ,

L is an optionally substituted methine radical;

R- is an optionally substituted alkyl, alkenyl or aryl radical;

Y the atoms required to complete an aryl radical and

Z «those to complete a 5 * or 6-membered heterocyclic Core required atoms.

In the structural formula I given, L can be, for example, a radical of the formulas: -CH = or -C (CH ₃ ) =.

If Rh represents an optionally substituted alkyl radical, then it can preferably have 1 to 18 carbon atoms, in particular Have 1 to 4 carbon atoms. Ry can for example be a methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, Isobutyl, tert-butyl, pentyl, hexyl, octyl, decyl, dodecyl, or octadecyl radical. R ^ can further, for example, a Being an aralkyl radical, preferably with a short-chain alkyl radical with 1 to 4 carbon atoms, for example a benzyl, ß-phen

3098 107 103B

ethyl or ω-phenbutyl radical. R ^ can also be, for example, a sulfoalkyl radical, preferably a sulfoalkyl radical with a short-chain alkyl radical with 1 to 4 carbon atoms, for example a β-sulfoethyl, γ-sulfopropyl, γ-sulfobutyl or Δ-sulfobutyl radical. R. can also be, for example, a carboxyalkyl radical, preferably with a short-chain alkyl radical with 1 to 4 carbon atoms, for example a β-carboxyethyl, γ-carboxypropyl or Δ-carboxybutyl radical. R * can also be, for example, a sulfatoalkyl radical, preferably with a short-chain alkyl radical with 1 to 4 carbon atoms, for example a β-sulfatoethyl, γ-sulfatopropyl or Δ-sulfatobutyl radical. Further R ^ can be, for example, an alkoxyalkyl group, preferably with short chain alkoxy, and short chain alkyl group having 1 to 4 carbon atoms, for example, a ß-methoxyethyl, γ-methoxypropyl or Δ-Propoxybutylrest _t or acyloxyalkyl group, preferably a lower alkyl with 1 to 4 carbon atoms, for example an acetyloxyethyl, propanoyloxyethyl, butanoyloxybutyl, benzoyloxyethyl or toloyloxypropyl radical, also an alkoxycarbonylalkyl radical with preferably short-chain alkoxy and alkyl radicals with 1 to 4 carbon atoms each, e.g. or ß-butoxycarbonylethyl radical, also a dialkylaminoalkyl radical, preferably with 2 short-chain alkyl radicals with 1 to 4 carbon atoms, for example a dimethylaminoäthy1-, diethy1amiηopropy1- or diethylaminobutyl radical, also a cycloaminoalkyl radical, preferably with 4 to 6 carbon atoms in the cycloamino radical and 1 to 4 carbon atoms n in the alkyl radical, for example a 1-pyrrolidinylethyl, 4-morpholinopropyl, 1-piperidinobutyl or a 2-pyrrolin-i-ylmethyl radical.

If R _{1 is} an alkenyl radical, this is preferably short-chain and has 2 to 4 carbon atoms. Typical alkenyl radicals are allyl, 1-propenyl, 1-butenyl and 2-butenyl radicals.

309810/1035

■ - 7 - ■

If R- has the meaning of an aryl radical, this exists preferably from an aryl radical of the phenyl or naphthyl series. This means that Pv- can for example be a phenyl-, Naphthyl, ToIy1-, XyIyI- or halophenyl radical, for example a p-chlorophenyl, p-bromophenyl radical or an alkoxyphenyl radical, for example a methoxyphenyl radical or a 2,4-dichlorophenyl radical. ,

The aryl group completed by Y is substituted by a nitro group in the ortho position. Preferably also in para-position a nitro radical or another electron withdrawing residue Remainder, with the proviso that this aryl group can furthermore be substituted by other groups and atoms and condensed on may have carbocyclic rings. This means that the aryl group completed by Y can be, for example, a 2-nitrophenyl, 2,4-dinitrophenyl-, 2,6-dinitrophenyl-, 2,4,6-trinitrophenyl-, 2-nitronaphthyl-, 2,4-dinitronaphthyl-, 2-nitro-4-cyanophenyl-, 2-nitro-4-ethoxycarbonylphenyl or a 2-nitro-4-trifluoromethylphenyl radical.

Zh-stands for the non-metallic atoms that make up a heterocyclic nucleus with preferably 5 to 6 atoms are required, as is customary for cyanine dyes are. The kernels completed by Z * can also necessarily present nitrogen atom have a second hetero atom, for example an oxygen, nitrogen, selenium or Sulfur atom. In particular, Z * can be used for the Atoms that are required to complete one of the following nuclei:

an optionally substituted thiazole nucleus, including an optionally substituted benzothiazole or naphthothiazole nucleus, e.g. a thiazole, 4-methylthiazole, 4-phenylthiazole, 4,5-diphenylthiazole, 4- (2-thienyl) thiazole, benzothiazole, 4-chlorobenzothiazole, 4-methylbenzothiazole, 4-methoxybenzo

309810/1035

thiazole, 4-ethoxybenzothiazole, 4-phenylbenzothiazole, 5-chlorobenzothiazole, 5-bromobenzothiazole, 5-methylbenzothiazole, 5-methoxybenzothiazole, 5-ethoxybenzothiazole, 5-phenylbenzothiazole, 6-chlorobenzothiazole, 6-bromobenzothiazole, 6-methylbenzothiazole, 6-methoxybenzothiazole-> 6-ethoxybenzothiazole-, 5-methoxynaphtha / "2,3-d_7thiazole-, ß-naphtothiazole, α-naphthothiazole, 5-nitrobenzothiazole, 6-nitrobenzothiazole or a 5-chloro-6-nitrobenzothiazole nucleus;

an oxazole nucleus, including an optionally substituted one Benzoxazole and naphthoxazole nucleus, e.g. an oxazole, 4-phenyloxazole, benzoxazole, 5-chlorobenzoxazole, 5-methylbenzoxazole, 5-bromobenzoxazole, 5-methoxybenzoxazole, 5-ethoxybenzoxazole, 5-phenylbenzoxazole, 5-methoxynaphthoxazole, 5-nitrobenzoxazole, 6-nitrobenzoxazole or an S-chloro-6-nitrobenzoxazole nucleus;

a selenazole nucleus, including an optionally substituted one Benzoselenazole and naphthoselenazole nucleus, e.g. of a selenazole, 4-methylselenazole, 4-nitroselenazole, 4-phenylselenazole, Benzoselenazole, 5-chlorobenzoselenazole, 6-chlorobenzoselenazole, Naphtho / "2,1-d_7selenazole-, 5-nitrobenzoselenazole-, 6-nitrobenzoselenazole-, S-chloro-ö-nitrobenzoselenazole- or one naphthoselenazole nucleus substituted by a nitro radical;

a thiazoline nucleus, e.g. a thiazoline, 4-methylthiazoline or 4-nitrothiazoline nucleus;

a 2-pyridine nucleus, e.g., a 2-pyridine or 5-methyl-2-pyridine nucleus;

a 4-pyridine nucleus, e.g., a 4-pyridine, 3-methyl-4-pyridine nucleus or a pyridine nucleus substituted by a nitro radical;

309810/1035

a 3,3-dialkylindolenine nucleus, e.g. a 3,3-dimethylindolenine, 3,3-diethyl-5- or 6-cyanoindolenine- or a 3,3-diethyl-5- or 6-nitroindolenine nucleus or a 3,3-dimethy1-5- or 6-nitroindolenine nucleus;

an imidazole nucleus, e.g. an imidazole, 1-alkylimidazole, benz imidazole, 1,3-dialkyl or 1,3-diaryl or a 1-alkyl-3-arylimidazole nucleus or a benzimidazole nucleus, for example a 5-chloro-i, 3-dialkylbenzimidazole nucleus or a 5-chloro-1,3-diarylbenzimidazole nucleus or a 5,6-dichloro-1,3-diarylbenzimidazole nucleus or a 5-methoxy-1,3-dialkylbenzimidazole nucleus or a 5-methoxy-1,3-diarylbenziniidazole or a 5-cyano-1,3-dialkylbenzimidazöl- or a 5-cyano-1,3-diarylbenziinidazole or a 1,3-dialkyliaphth / "i, 2-d_7imidazole or a 1,3-diarylnaphth /" 2,1-d_ / imidazole nucleus;

a quinoline nucleus, e.g. a quinoline-TJö-methylchiftolin-, 6-methoxyquinoline, 6-thoxyquinoline, 6-chloroquinoline, 4-methoxyquinoline, 4-methylquinoline, 8-methoxyquinoline, ß-methylquinoline, 4-chloroquinoline or a 6-nitroquinoline nucleus;

imidazo a / _{"4> 5-r} b_7chinöxalinkernes example of the in. US Patent No. 3,431,111 known type, for example an imidazo l ~ 4, 5-b_7chinoxalin-, 1,3-Dialkylimidäzo / 4,5-b_7chinoxalinkernes, for example a 1,3-diethylijnidazo ^ "4,5-b_7chlno3calinkern or a 6-chloro-1 _> 3-diethylimidazo /" 4, S-b_7Ghinoxalinkern or a 1,3-dialkenylimidazo / "4 _> 5-b_7chinoxalinkern _i for example a 1,3 .-I) iallylimidazo / ~ 4, Sb ^ / quinoxaline or a 6-chloro-1,3-diallylimidazo / ~ 4,5-b_7chlnoxalinkern or a 1,3-diarylimidazo - / "4,5-b_ _- 7chliioxalinkern _> for example a 1,3-diphenylimidazo _/ / ~ 4 _)! 5-b_7-quinoxaline or a 6-chloro-1,3-diphenylimidazo / ~ 4,5-b_ _> 7-quinoxaline nucleus;

3 ö 9 S 1 0/1 Ö 3 p

a 3H-pyrrolo / 2,3-b_7pyridine nucleus, e.g. a 3,3-dialkyl-3H-pyrrolo / ~ 2,3-b_ / pyridine nucleus, e.g. a 3,3-dimethyl-3fI-pyrrolo / "2,3-b7pyridin-, 3,3-diethyl-3II-pyrrolo / ~ 2, 3-b_ / pyridine- or a 1,3,3-trialkyl-3H-pyrrolo / ~ 2,3-b-7-pyridine nucleus, e.g. a 1,3,3-triethyl-3H-pyrrolo / ~ 2,3-b_7pyridinkernes or one

Thiazolo / ~ 4,5-b-7-quinoline nucleus.

The nitro-substituted dyes used according to the invention not only have excellent photobleaching properties, but are also thermally stable through their melting points addition, and make excellent desensitizers for photographic silver halide emulsions.

Dyes of the formula I given, in which k = 0, can be advantageously by reacting a heterocyclic ammonium salt of the formula:

χ ^θ

with a nitro-substituted compound of the following formula:

, C
III. G— <v Y

produce. In the formulas II and III, ni, R *, Z .., L and Y have the meanings already given. G represents an ilalogenide radical, for example a fluoride, chloride or bromide radical, and X is an acid anion, for example a halide anion _r e.g. a chloride, bromide or iodide anion or for example a p-

309810/1035

Tbluenesulfonate, thiocyanate, sulfamate, perchlorate, fluoroborate, Methyl sulfonate, ethyl sulfonate, fluorosulfonate or 2,4-dinitrobenzenesulfonate anion.

The production of the dyes used according to the invention is based thus on a nucleophilic substitution of the substituent G the nitro-substituted aryl compound of the formula III by a compound of the formula II. The reaction is preferably carried out in a suitable solvent. Suitable solvents include common non-nucleophilic solvents, such as acetonitrile, benzene, dimethylformamide, tetrahydrofuran, Acetone, ether and the like. The amount of solvent used is not critical, although it is preferred to use sufficient solvent to produce a liquid reaction mixture. It has proven to be useful, for example proved to use 2 to 10 weight units of solvent per unit weight of reaction components.

The reaction is expediently carried out at elevated temperatures to accelerate the reaction. The process can advantageously be carried out at temperatures of about 40 to about 150 ° C., in particular at temperatures of 60 to about TOO ⁰ C.

A solvent is used that has a boiling point at atmospheric / fem pressure which is in the range specified as preferred, so that the reaction takes place at the reflux temperature of the reaction mixture can be carried out.

The reaction is usually complete within 1 to 3 hours. The reaction product can then according to customary known Methods "." Can be isolated from the reaction mixture. If acetonitrile Used as the reaction solvent, the dyes are generally obtained in crystalline form when the reaction mixture is cooled to room temperature and for several hours is left standing.

309810/1035

Dyes of the given general formula, in which k = 0, or 2, etc., and is usually greater than 0, can be obtained by reacting a heterocyclic ammonium salt of Form1:

with a nitro compound of the following formula:

, C 1

NO ₂

produce, where in the formulas IV and Vm, R-, Zj, L, Y and X have the meanings already given and where it also applies that R _? is a displaceable electrophilic radical, for example an anilino, acetanilino, alkoxy or mercapto radical or an Ilalogenatom and η = 0, 1 or 2 represents.

The reaction is expediently carried out in the presence of a base-solvent combination. For this purpose, preference is given to using non-nucleophilic bases, such as, for example, diisopropylethylamine, sodium hydride and ßutyllithium are used. Typical, suitable solvents are, for example, tetrahydrofuran, dioxane, dimethyl sulfoxide and acetonitrile.

The reaction temperatures and reaction times correspond to aforementioned method.

As already stated, the dyes used according to the invention have excellent photobleaching properties, i.e. the Dyes represent colored compounds until they are exposed to electromagnetic radiation to which they are sensitive.

309810/1035

are borrowed. The exposure thus removes the dyes or "faded" in such a way that their absorption is reduced considerably. Many of the dyes which can be used according to the invention bleach both in solution and as in the solid state, although the rate of fading is generally greater when the dyes are in dissolved form.

The relative rate of fading of various compounds depends on various factors, for example the heterocyclic radical with the atom functioning as an electron donor, for example in formula I the part of the formula which contains the ring with Z * . The rate of fading also depends on the number of nitro residues on the aryl ring and their position in relation to the methine chain. o-Nitro-substituted / fade very quickly. The presence of a second o-nitro substituent generally reduces the rate of photobleaching in the case of the dyes in which Y represents the atoms necessary to complete a phenyl radical. , Bleach the other hand, i ^ iron '2,4-dinitro-substituted phenyls a relatively high fading rate to, t) m is generally greater than the speed with which correspondingly simple o-nitro-substituted dyes.

The dyes used according to the invention can not be used ionic solvents, e.g. toluene, acetone, dichloromethane, Dissolve dioxane, dimethylformamide and the like. Furthermore, they can also be dissolved in polymeric solutions, for example in Solutions of polyvinylpyridine in acetone and methanol or in solutions of copolymers of butyl acrylate and styrene in ethyl acetate. Due to the favorable thermal stability of this Dyes can also be dissolved or homogeneously dispersed in a wide variety of polymers, for example in poly-a-olefins, e.g. polyethylene, by mixing the dye with granulated

/ "Dyes · '

3098 10/1035

and
Polymer, Melters Blending / Blending Until Achieved

a homogeneous state.

In a particularly advantageous manner, the property of the dyes to be photobleachable can be used for antihalation protection use photographic recording materials, in particular photographic silver halide recording materials. After exposure and development of such recording materials the color caused by the antihalation layer can easily be destroyed, for example by simple Exposure to light, rather than chemical or physical removal, or fading from heat.

Due to their properties, the dyes described can be thus excellent for the production of photographic support, i.e. work into photographic support.

The photographic materials according to the invention can thus order among other things from photographic supports which contain one or more of the arylidene dyes incorporated.

A wide variety of customary substrate materials can be used to produce the substrate, either Have a melting point which is below the decomposition temperature of the dye (s) or which is in a solvent are solvable, in which the one or those used according to the invention Dyes are soluble, so that a polymer dye solution can be produced, which is then processed into a film carrier can be. Typical polymers that can be used in the manufacture of photographic supports with incorporated arylidene dyes suitable according to the invention are, for example, cellulose nitrate, cellulose acetate, polyvinyl acetal, polystyrene, polyethylene terephthalate, Polycarbonate and other corresponding resinous polymers.

8AD ORIQfNAL 309810/1035

The production of a photographic layer support according to Invention with incorporated photobleachable arylidene dye can thus take place, for example, by the fact that the photo-recoverable Dye is mixed with the polymer, preferably in the form of granules or a powder, whereupon the Mixture is melted with further mixing. The one with it resulting homogeneous solution of the dye in the polymer can then can be processed into a photographic film layer carrier in a conventional manner, for example by extrusion.

The photographic supports thus obtained make excellent substrates for photosensitive Silver halide coating compositions that provide antihalation protection require, represent.

However, the dyes used in the present invention can optionally can also be applied to a layer support, in particular together with a suitable binder, in which they are distributed, for example a binder made of a polymer, as specified for the production of the support VUrden.

Photograph! See substrate with a layer of an in photobleachable dye distributed with a suitable binder provide advantageous support with drawn, tem Li chthofsc'iutz, which can be used for the production of a wide variety of recording materials, the example trip for dry development, through the action of Heat are intended.

Examples of photographic recording materials, to their Production of the layer support according to the invention with antihalation protection The light-sensitive and thermo-sensitive can be used iclien on signs such as those for example

309810/1035

in Belgian patents 766 589 and 772 371 and the

U.S. Patents 3,457,075, 3,409,438, 3,152,904, 3,392,020 ί

and British patents 1,163,187 and 1,161,777

be written. . \

The layer supports provided with antihalation protection according to the The invention can also be used, for example, for the production of photothermographic recording materials which!

an image-forming layer having a combination ion of an oxidizing agent and have reducing agents, for example with a combination of a heavy metal salt!

the oxidizing agent and a reducing agent and photosensitive agent Silver halide in a polymeric binder.

The photobleachable properties of those used according to the invention As already explained, nitro-substituted dyes can also be used advantageously for the production of photographic materials Exploit images. The dyes used in the present invention can be used for the production of light-sensitive photographic materials Recording materials containing one or more of the photobleachable dyes can be used. Such recording materials can then be exposed to the image to be recorded using electromagnetic radiation opposite to it The dyes used are sensitive, the exposure time depending on the desired degree of fading. The on Images obtained in this way can then be viewed in low-intensity light or in non-lighting conditions contains electromagnetic radiation, the-opposite of the or "the Dyes are sensitive.

Such photosensitive recording materials according to the invention are outstandingly suitable for the production of Test images (proof images), which, if desired, by means of

309810/1035

conventional photographic recording materials can be copied and thus recorded permanently. In the event of , of photoresist materials, for example, it is often desirable to pre-determine the exposure level and get an impression of the image to be produced before the etching process is carried out. The invention thus creates a simple one Process that the image obtained by the fading can later be completely destroyed by a full exposure the image areas with light to which the dye or dyes are sensitive.

According to a further embodiment of the invention, there is photographic recording material made from a photosensitive Photographic material comprising a support and a binder coated thereon may include one or more herein distributed dyes. Such photographic recording materials according to the invention can be produced in that a dispersion of one or more of those used according to the invention bleachable dyes in a binder is applied to a support. The dispersions for production the recording materials can be produced in various ways. One method is to start with a 5 to KHige solution of the binding agent in a suitable solvent and then saturate the solution with the dye.

A wide variety of customary known binders can be used to produce the recording materials naturally occurring substances, e.g. B. proteins, e.g. gelatin, Gelatin derivatives, cellulose derivatives, polysaccharides such as dextran and gum arabic and the like as well synthetic polymers, e.g. polymers and copolymers of polyvinylpyridine and of butyl acrylate and of styrene, for example copolymers of butyl acrylate and styrene.

309810/103 5

The customary known solvents can be used to produce the photosensitive layers, in particular those in which the binders are readily soluble. Solvents of low molecular weight have proven to be particularly suitable and relatively high volatility, such as acetone, methyl ethyl ketone, methanol, ethyl acetate and butyl acetate. If binders, such as gelatine, are used that can be dissolved in water, it may be necessary to use the or to dissolve the dyes in another solvent and to form the resulting dye solution in the binder solution to disperse an emulsion.

For the production of the recording materials, the usual known supports are used, such as those used for the production of photographic recording materials, for example, substrates made of glass, paper, metal and the like as well as synthetic polymers.

The application of the coating compounds, i.e. the dispersion of the or the dyes in the binder solution can be carried out in the customary known manner, for example by dip coating, Coating by means of an air knife, by curtain coating, by coating by means of an extruder or a coating funnel, for example of the type known from U.S. Patent 2,681,294. Optionally, two or more Layers simultaneously applied to the layer carrier, for example, according to the method as described in US Pat. No. Lt 2,761,791 and British Patent 837 095 are known. The thickness of the coating in which the dispersion is applied to the substrate is applied, can be very different, depending on the properties of the dispersions to be applied as well as on the desired results. As a rule, it has proven to be useful proven 5 to KU solutions of the Cindy remedy with the or the dyes are silttii'.t, in a Schichisturkc of wet

3 0 9 B 1 0 /] 0 3 5

measured 0.127 to 0.51 mm. Before using the recording material, the applied layer can be applied in the usual way Way to be dried up.

The recording material produced in this way can then are exposed, with electromagnetic radiation, the opposite the dye or dyes of the recording material are sensitive.

Since the dyes fade on exposure, the use of such a recording material does not require any further Process steps after exposure of the material.

The electromagnetic radiation to which the dyes used according to the invention are sensitive can differ somewhat from dye to dye. The electromagnetic radiation range extends from the range of longer-wave ultraviolet light to the infrared range, but is generally in the visible range. As a result, the exposure can be carried out, for example, with a conventional tungsten lamp, the exposure time depending on the intensity of the light source. For example, dyes according to the invention on Keniger can be bleached out to more than 10% of their original density when exposed for 15 seconds to a 500 watt tungsten lamp such as a lamp found in commercial projectors ^{such as a Kodak Carousel u projector} , although longer exposures can of course also take place for fading, for example with light sources of lower intensity and / or light sources which are set up at a greater distance from the photosensitive recording material.

810/1035

The photographic images obtained in this way are not stabilized, i.e. the recording material retains its Sensitivity to electromagnetic radiation. As a result, the fading process will continue when the produced image is viewed under normal lighting conditions. As the intensity of a normal room exposure in general is less than the intensity of the light source used to expose the recording material, the produced pictures usually several minutes or longer consider without significant degradation. If the picture is then to be deleted later, this can be done easily be done in such a way that the image is fully exposed for a certain time.

Due to the instability of the photographic images that can be produced the photographic recording materials according to the invention are outstandingly suitable for the production of test images (proof images). If a permanent or durable copy of the test image is to be made, this can easily be done by that the test image is photocopied using conventionally known photographic recording materials. In many cases, as mentioned earlier, using photoresist materials for making printing plates by etching and printed circuit boards, all that is required is the formation of a non-permanent image or desirable.

The dyes used according to the invention are suitable also excellent as desensitizers for photographic silver halide emulsions. Under a desensitizer for photographic silver halide emulsions, dyes are to be understood which, after addition to a gelatin silver bromide iodide emulsion with 2.5 MoI-I silver iodide in a concentration of 0.01 to 0.4 g of dye per mole of silver to one Loss of the emulsion's sensitivity to blue if this

3Ö9I1Ö / 1035

■ --21-. ■. ■ /

exposed sensitometrically and developed for 6 minutes in a p-methylaminophenol sulfate hydroquinone developer at room temperature. Desensitizers which, when tested in the manner described, lead to a loss of at least 50 % and preferably at least 90% or more of the sensitivity to blue radiation are particularly advantageous. . *

In the case of their use as a desensitizer can the dyes used according to the invention are more commonly known Manner in silver halide emulsions, for example gelatin-silver halide emulsions be dispersed, for example by dissolving in a suitable solvent such as ethyl acetate and Mix the solution with the silver halide emulsion until a homogeneous mixture is obtained. Can advantageously the mixing takes place in a colloid mill or in a corresponding device. The obtained in this way Silver halide emulsions can then be coated on substrates in a conventional manner. The usual known substrate and coating methods are used. The recording materials thus obtained can be developed in by customary known methods, for example using p-methylaminophenol sulfate hydroquinone developers, fix, wash and dry.

The photobleachable dyes used according to the invention are also valuable sensitizers for organic photoconductors in electrophotographic recording materials. Because of their bleachable properties, the dyes can be used particularly advantageously in this field of application. After the photographic copy has been made, it can be exposed to electromagnetic radiation, normally Room light or daylight, to which the dyes are sensitive. In this way the dyes can be colorless or

3 Q 9 8 1 ü / 1 U 3 5

practically colorless compounds will fade, resulting in an increase in the contrast between the toner and the background the copy leads.

The following examples are intended to illustrate the invention in more detail.

example 1

^a ) Production of the dyes

The 2,4-dinitrobenzylidenes listed in Table 1 below were used manufactured.

5 g of a quaternized salt of the formula R CHjX, in which R has the meaning given in Table 1 below and X is an acid anion, is expedient a p-toluenesulfonate anion, to a solution of 50 ml Acetonitrile and 3 1/2 ml of the non-nucleophilic tertiary Amine di-isopropylethylamine was added. To the reaction mixture 3 ml of i-fluoro-2,4-dinitrobenzene were then added, whereupon the resulting mixture was refluxed for 1 to 3 hours. The resulting solution was then cooled and left to stand overnight, whereupon the crystalline reaction product separated out. It was filtered off and off Benzene recrystallized.

b) Use of the dyes

The dyes listed in Table 1 below were each dissolved in toluene or benzene, whereupon the obtained Solutions of exposure to yellow fluorescent / have been exposed to the visible light of for the most part with Emitted wavelengths greater than 49 nm.

/ "Light

30931G / 1U35

2242781

In Table 1, the photobleachability 1 corresponds to one Phot oausb Ie ich-IIalwertzeit from 20 to 25 minutes, whereas the photobleachability 2 indicates a photobleaching half-life of one hour or more.

All of the dyes tested were 2,4- * dinitrobenzylidenes of the following structural formula:

-fX-;

R = CH

NO ₂

where R has the meaning shown in Table 1 below.

- 24 -

309§1Ö / 1Ö3 £

Tabel

dye

^C 2 ^H 5

Solution Amax (nm)

Mp ⁰ C

Photo fade ability

520 265-266 1

^C 2 ^Ü 5

491 278-281 1

CH ₃ CH ₃

CU

Cl

Allyl

497 272-274

490 145-147

505 166-168 1

309810/1035

OFWGlNAL INSPECTED

- 25 Table 1 (continued)

VI

CH, CH

VII

461

514

123-126 2

515 299-3OO ^a) 1

246-247

a) Recrystallized from dimethyl sulfoxide.

Example 2

In various proportions of a gelatin silver bromide iodide emulsion with 2 »5 mol-I iodide were those in the following table listed dyes in a concentration of 200 mg dye added per mole of silver bromide jadide.

The emulsions thus obtained were then carried on cellulose acetate film supports applied in a layer thickness of 100 mg silver per 0.0929 m. Test objects of the Ktr

3 0 9 8 1 NC / 1 0 3

drawing materials were then used with a mercury vapor lamp, which emitted radiation with a wavelength of predominantly 365 nm, exposed for 6 minutes in a p-methylaminophenol sulfate hydroquinone developer developed, fixed »washed and dried. The results obtained are in the Table 2 below. From the result obtained sen it is found that the dye used according to the invention lead to a desensitization of the emulsion used.

Table 2

Dye a) Relative Photographic Speed

without 100

I 4.6

II, 3.6

III 4.5

a) see table 1
Example 3

There have been several other photosensitive recording materials produced by applying dispersions of dyes in gelatin to the support.

A dispersion 1 was prepared by dissolving the dye used in tricresyl phosphate and dispersing the obtained Solution in gelatin. The dispersion took place by passing the solution-gelatin mixture several times through a colloid mill as is known from US Pat. No. 2,322,207.

309810/1035

A dispersion 2 was made without using a high boiling point Solvent according to the US Pat. No. 2,801,171 • known methods produced.

The dispersions x \ mrden each applied to conventional polyester layer support in a layer thickness corresponding to 10 mg of dye per 0.0929 m ^{2 of support} surface.

The thermal stability of the recording materials produced was determined by ^{heating the test specimens on a metal block at 200 °} C. for 10 seconds.

The photobleachability of the recording materials was thereby increased determined that the test specimens were exposed to a 500 watt tungsten lamp was exposed.

The storage stability of the test specimens was determined by exposing them to a temperature of 49 ^° C. for 1 week at a relative humidity of 50%.

The optical density values listed in Table 3a below were determined in a densitometer at the wavelength of maximum absorption.

- 28 -

309810/1035

Table 3a

Dye- Disper- max. Fabric sion nm. A)

V.

540 610 510 525 510 520 480 530 530 565 615 575

Fresh material

Heat test

Light exposition

Heat test + light exposure

Incubated material

0.300 0.145 0.305 0.280 0.750 0.780 0.580 0.550 0.500 0.410 0.595 0.610

0.410 0.160 0.560 0.515 0.790 0.885 1.000 0.920 0.640 0.285 0.660 0.940

0.100 0.100 0.110 0.105 0.120 0.110 0.150 0.120 0.105 0.150 0.100 0.400 0.160 0.115 0.200 0.220 0.200 0.180 0.240 0.190 0.170 0.240 0.160 0.210

0.272

0.365 0.280 0.767 0.730 0.617 0.483 0.520 0.282 0.595 0.600

a) The composition of dyes I to YIII results from Table 1. The composition of the dyes IX to XII gives from the following table 3b.

Table 3b

CH-CH

309810/1035 ORIGINAL INSPECTED

Dye An X

IX S. O 2,4-di-NO ₂ X S. O 2,4,6-tri-NO ₂ XI S. 1 2,4-di-NO ₂ XII Se O 2,4,6-tri-NO ₂ Example 4

There were other photosensitive recording materials prepared by saturating polymer solutions with one of the dyes listed in Table 4.

The solutions obtained were then applied to polyester film supports plotted that layers of, measured wet, 0.203 mm thick were obtained. The layers were then allowed to dry up calmly. The dried layers were then exposed through a test image using a 150 watt tungsten lamp. After Exposure revealed that the layers were bleached imagewise in relation to the irradiated radiation.

The recording materials with the dyes VI, IX and XII were exposed to the corresponding color search positives. To the exposure was determined by superimposing the three exposed Recording materials receive a positive color image.

A permanent copy of this color image can be obtained by that the color image is copied onto a conventional color photographic recording material.

The structure of the ^{dyes listed in Table 4 T} below is obtained by inserting the groups given for E into the ¥ ®t®elm «listed in Example ΐ

30fl81Q / t03B

Table 4

dye

XIII

C ₂ H ₅ -

IX see table 3b

VI see table 1 I see table 1

XIV

Solvent + polymer

hue

10% polyvinylpyridine in 1: 1 acetone: methanol

5% polymer made from butyl acrylate and styrene in ethyl acetate

SI polymer from butyl acrylate and styrene in ethyl acetate

blue green

purple

yellow

purple

purple

IV see table 1

orange

Example 5

Two photographic film supports were included in them distributed thermally stable, light-bleachable dyes produced by thoroughly adding 0.16 g of dye in each case 60 g of polyethylene were mixed and melted. The melts then became polyethylene films of various kinds at 177 ° C Processed starch. One support contained dye VIII from Example 1 as the dye and the other support contained the dye XVIII, i.e. 2- (2,4-dinitro-1-naphthylmethylene) -1,3-diethyl-2,3-dihydro-1H-imidazo / "4,5-b-7quinoxaline. ;

309310/1035

A visual examination of the support obtained showed that the substrate had areas with dissolved dye and dye crystals in polyethylene. Both the districts with the dye crystals as well as the districts with the uniform distributed dye could be bleached.

Example 6

Several film supports were made by 0.16 g of the dye VIII of Example 1 and 60 g of polyethylene mixed for 15 minutes at a temperature of 170 C, the The resulting melts are allowed to solidify and the solidified melts are comminuted, again to 170 ° C with the formation of more homogeneous Solutions of the dye in polyethylene melted and formed into foils with a layer thickness of 0.009144 cm at one of the in Table 5 temperature indicated were extruded.

All of the samples were uniform in appearance, that is, no dye crystals were observed. The examinees were then washed with acetone to remove dye on the surface of the specimens. It was then determined the absorption of each test piece at 565 nm.

Table S.

Test item Extrusion temperature Absorption a) A. 2O4 ° C 0.15 B. 218 ⁰ C 0.19 C. 232 ° C 0.15 D. 26O ⁰ C. 0.21 E. 274 ⁰ C 0.26 F. 288 ⁰ C 0.21 G 316 ^D C 0.12

a) corrected taking into account the absorption of the pure Backing material with 0.06 absorption units.

3098 10/103 S.

ι The test items E to G showed some streaks of dye. Velvet j

Lent test specimens could be exposed to a remaining one

optical density of 0.06 at 565 nm. ;

Example 7 j

Other photographic film supports were made. j

For this, 2.0 g of a thermally stable photobleachable '

Dye (see the following table 6) with 2270 g of polyethylene '

mixed terephthalate. The mixture was then in one up.}

melting vessel melted and extruded into film carriers using an extruder at a temperature of 26O ⁰ C. The supports thus obtained showed a uniform appearance with no dye crystals. The supports were then bleached by exposure to the light of a tungsten lamp.

The optical density of the non-bleached support at Xmax of the dyes used and the density were determined the bleached substrate at 400 nm.

Table 6

Color
material Xmax I. 540 II 505 Example 1 8

Density of not booked density of booked »

bleached substrate

carrier

0.54 0.06

0.90 0.04

Another photographic film base was prepared. For the preparation of the support of the dye was used VIII of Example. 1 The dye was mixed with polyethylene terephthalate, whereupon the melt was extruded to form a substrate with a layer thickness of 0.10. So much of the dye was used that the optical density

309810/1035 original inspected

- 33 of the support was 0.60.

A second support with an optical density of 0.10 was produced in a similar manner. Finally it was a third layer support for comparison purposes with a layer thickness of 0.10 mm without dye.

At the same time, a light-sensitive silver halide photographic emulsion became prepared from the following components:

1 »silver bromide iodide

2. Gelatin ¹⁵ (10% in water)

3. Saponin (152.3 mg / ml water)

4. 3,3 * -Diethyloxacarbocyanininjödid (0.20 mg / ml methanol)

5. water

^a The silver bromide iodide had an average grain size of 0.2 microns. The silver bromide iodide grains were dispersed in gelatin.

The total amount of gelatine, i.e. the gelatine of the 1QtIgen Water solution and the gelatin that contains the silver bromide iodide was added, corresponded to a dry weight of 51 gelatine * based on the total weight of the sealing compound.

The emulsion ingredients 1 to jS were thoroughly mixed with each other mixed, whereupon the emulsion obtained on the three photographic Film support measured in a layer thickness of wet 0.203 mm were applied and dried :. ν

Samples of the obtained photographic recording materials were then exposed to a test object for 3 minutes in one p-Methy1aminophenoIsulphate ~ Hydraquinone ~ iatwiekler DEVELOPED »

66 ,8th G 2t6 , 0 G 4th "O ml 80 ml 193 .0. ml

fixed, washed and dried. The image qualities achieved are shown in Tables 7a and 7b below.

In the case of Table 7a, contact copying was carried out by the Test object (an image quality test card was used) and a 3.0 neutral density filter using a 500 watt nitrophot lamp, which had been set up at a distance of 50.8 cm.

Table 7a

Film layer
carrier density Exposure time Bi ideality comparison
0.10
0.60 10 sec.
It
ft 1
2
2 comparison
0.10
0.60 20 sec.
ti
tf 1
2
2

In the case of Table 7b, exposure was carried out in a conventional one Copier (Kodak Verifax Copier) through a 2.0 neutral density filter.

Table 7b

Film layer
wear you te Eligibility period Opportunity comparison
0.10
0.60 8 sec.
ti
dd 0
2
3 comparison
0.10
0.60 15 sec.
Il
ti 0
2
3

309810/1036

In Tables 7a and 7b, the number "O" shows under 'the "heading "Image quality" indicates a poor resolution of small and medium-sized letters and line art. The higher the specified resolution, the better the resolution Numerical value is. ·

Corresponding results were obtained when others " Nitroaryl dyes, for example the dyes I to VII of Example 1, were used.

In the following the production of a few more according to the invention usable dyes are described in more detail;

Dye XV

2- (2,4-Dinitrocinnamylidene) -1-ethy1-1,3-dihydroquinoline

CH-CH = CH

10.9 g of 2,4-dinitrotoluene, 8.0 g of 2- (2-anilinovinyl> 1-ethylquinoliniuin iodide and 4.1 ml of acetic anhydride were dissolved in 30 ml of dimethylformamide, whereupon the solution was brought to a temperature was heated near reflux temperature. Then 8.4 ml of triethylamine were added added, after which the mixture was heated to reflux temperature for a further 1 minute. The solution then became rapid cooled and filtered. The filtered precipitate of the dye was washed with dimethylformamide and methanol and dried. 6.55 g of high dye, corresponding to 901 of theory, were obtained. The high dye was then purified,

309810/1035

inde »he dissolved in dimethylformamide» the solution with methanol '

diluted and the dye allowed to crystallize. i

The crystalline dye was obtained in a yield of 32 l

keep. The melting point was 230 to 231 ⁰ C {dec.} DerAmax- i

The value in acetone was 623 na.>

The dye 4- (2,4-DinitrocinnaRiy-)

liden) -1 ~ ethyl-1,4-dihydroquinoline can be produced. The dyes \ material had a Schaelzpunkt of 229 to 23O ⁰ C (dec.). Of the

Xmax in acetone was 660 nm. J

Dye XVI

4- (2,6-Dinitrobenzylidene) -1-ethyl-1,4-dihydroquinoline

NO,

3.0 g of 1-ethyllepidinium iodide and 2.5 g of 1-chloro-2,6-dinitrobenzene
were warmed up in 50 ml of acetonitrile, whereupon 2.6 g of diisopropylethylamine were added. The resulting dark mixture was
then cool and let stand overnight. The resulting precipitate of the dye was filtered off and washed with
Acetonitrile and ether washed. After recrystallization from acetonitrile, 0.85 g of dye, corresponding to 251 of theory,
obtain. The dye had a melting point of 15 ° to 155 ° C
(dec.) on.

OftenJÖlNAL INSPECTED

3 0 9 8 10/1035

Dye XVII

4- (4-Ethoxycarbonyl-2-nitrobenzylidene) -1-ethyl-1,4-dihydroquinoline

C ₂ H ₅ -N Jc = CH - < y - COOC ₂ H ₅

5.8 g of 1-ethyllepidiniuinjodid and 4.6 g of ethyl 4-chloro-3-nitrobenzoate were stirred with 50 ml of acetonitrile. 5.2 g of diisopropylethylamine were then added, whereupon the mixture obtained was heated to reflux temperature for 6 hours by means of a steam bath. The mixture was then dissolved in 500 ml of ether and extracted 5 with 200 ml portions of water. The ether extract was then dried over anhydrous magnesium sulfate. The dried ethereal solution was then evaporated to dryness, whereupon the residue was taken up in 25 ml of ether. The ethereal solution obtained was placed in the cold overnight. The dye precipitated out. It "was filtered off, washed with ether and petroleum ether" and dried. The yield of dye was 2.8 g, corresponding to 40% of theory. The melting point of the dye was about 1QO ⁰ C.

at The dyes XVI and XVII could be found in ethyl acetate solutions fade as fast as the dyes listed in Table I,

Dye XVIII

4- (2,4-Dinitrobenzylidine) -2,6-diphenyl ~ 4H-pyran

309810 / 103S

^C 6 ^H 5

1.0 g of 2,6-diphenyl-4-methylpyryliurafluoborate and 0.56 g of 1-fluoro-2,4-dinitrobenzene were warmed up in 15 ml of acetonitrile. After adding 0.775 g of diisopropylethylamine, the reaction mixture turned dark and the reaction components dissolved. After standing overnight, a dark precipitate had formed, which was filtered off, washed with methanol and recrystallized from 100 ml of acetonitrile. There were 0.32 g of dye, corresponding to a 26 ^? .igen yield obtained. The melting point of the dye was 235 to 237 ^° C. (dec). The dye had an absorption maximum in acetonitrile at 480 nm.

The fading power of the dye corresponded to the fading power of the dyes listed in Table I.

The further dyes XIX and XX were produced according to the production process described. These dyes had corresponding ones Properties like the dyes listed in Examples I to VIII.

Dye no constitution

XIX 2r (2,4-dinitrobenzylidene) -4,6-diphenyl-2H-

pyran

309810/1036

^C 6 ^H 5

- 39 -

2- (2,4-Dinit tobeniylidene) -1,3-dithiolane

Example 9

Antihalation layers were applied to five film supports of polyethylene terephthalate. For this purpose, a coating composition of 0.5 g of the dye ΧΙΪΙ from Example 4 in 100 ml of a 6% solution of a thermoplastic polycarbonate condensation product of bisphenol A and phosgene (Lexan) in dichloroethane was applied to the support. In all cases a brilliant blue layer with an optical density of 2 ^ 0 at 640 nm was obtained.

One of the elements produced in this way was then exposed to room light for 40 minutes the element assumed a pale orange color. The density was 0.06 at 640 nm. For the entire region of the visible spectrum resulted in a density of less than 0.2.

A photosensitive was then applied to the remaining four elements heat developable layer composed of a coating composition as follows Composition applied:

30 9 810/1035

IAD

Silver behenate (of a purity
from about 60 to 701, with the impurities being low molecular weight fatty acids) 42.0 g

Behenic acid 32.0 g

Polyvinyl butyral 15.0 g

Acetone 250.0 ml

Toluene 250.0 ml

Phthalimide 8.5 g

NaBr (reacted with the silver behenate under

Formation of silver bromide "in situ") 2.4 g

After grinding the mixture in a ball mill for 18 hours 141 ml of the obtained dispersion was mixed with the following solutions;

4.4 ml of acetone, with 0.08% by weight of 3-ethyl-5- / ~ (3-ethyl-2- (3H) -benzothiazolylidene) isopropylidene_7-2-thio- 2,4-oxazolidinedione and

52.5 ml of acetone, with 6.25% by weight! 2.2 ^f -dihydroxy-1,1'-bi-

naphthyl

The mixture obtained by thorough mixing was then applied to the antihalation layer of the individual support elements and dried up. In this way, photosensitive and thermosensitive recording materials of 60 mg Silver obtained per 0.0929 m of support area. The recording materials were then exposed sensitometrically to the light of a tungsten lamp for 0.5 seconds. The obtained latent Images were then developed by bringing the recording materials into contact with a heated metal block. The temperatures of the metal block used and the contact times are listed in the following table:

309810/1035

material Time
(Sec.) temperature
( ⁰ G) min Max 2 15th 125 0.00 1, 54 3 10 130 0.00 1.46 4th 9 135 0.02 1.35 5 6th 140 0.04 1.30

The developed images were then exposed for 40 minutes of room fluorescent light exposed to the in the Fade dye contained in antihalation layers. In all cases, sharp images were obtained on a brownish background.

Example 10

The dye XV and the dye 4- (2,4-dinitrocinnamylidene) -1-ethyl-1,4-dihydroquinoline, prepared in a corresponding manner, were each dissolved in a solution of poly (dimethylacrylamide) in diisopropylethylamine and acetone. The solutions obtained were then applied to transparent film supports in the manner described in Example 4. The dyes were bleached out by exposing the layers to light. Products were obtained which had about 1/10 of the absorbance of the original dyes at 550 nm.

Claims (12)

PATENTAMSPRO C II E / \.) Photographic material with a photobleachable dye, characterized in that the photobleachable dye is an o-nitro-substituted arylidene dye, the o-nitroaryl radical of which is bonded via a methine chain to a basic heterocyclic radical with an atom acting as an electron donor the number of carbon atoms which connect the atom acting as electron donor to the aryl radical, corresponds to an even number, contains. 2. Photographic material according to claim 1, characterized in that that it is an o-nitro-substituted arylidene dye contains, whose atom acting as an electron donor consists of a nitrogen, oxygen, sulfur or selenium atom. 3. Photographic material according to Claims 1 and 2, characterized in that it is an o-nitro-substituted arylidene dye contains whose o-nitro-substituted aryl radical via an acyclic methine chain with an odd number of Methine groups on a basic, N-containing 5- or 6-membered heterocyclic ring. 4. Photographic material according to Claims 1 to 3, characterized in that that it contains an o-nitro-substituted arylidene dye of the following formula: • Z ₁ 1 _r ι 1 j / C ι ι ^sCH * k — vy NO ₂ 309810/1035 - 43 where mean: lc = 0 or 1; mn = 0 or 1; ■ L is an optionally substituted methine radical; R. an optionally substituted alkyl, alkenyl or Aryl radical; Z ₁ the atoms required to complete a 5- or 6-membered basic heterocyclic nucleus and Y those required to complete an aryl radical Atoms. 5. Photographic material according to claim 4, characterized in that it contains an o-nitro-substituted arylidene dye of the formula given, in which Z stands for the atoms which make up an oxazole, selenazole, thiazbline, pyridine, imidazole , Ciiinoline-, indolenine-, imidazo / 4 _> 5-b_ / quinoxaline, 3H-pyrrolo / ~ 2,3-b-7-pyridine or a thiazolo / 4,5-b-7-quinoline nucleus. 6. Photographic material according to claim S, characterized in that that it contains one of the following dyes as an o-nitro-substituted arylidene dye: (a) 2- C2,4-dinitrobenzylidene) -1,3-diethyl-2,3-dihydro-1H-imidazo / ~ 4,5-b-7quinoxaline; (b) 2- (2,4-Dinitrobenzylidene) -3-ethyl-2,3-dihydrothiazolo- / 4,5-b_ / quinoline; (c) 2- (2,4-dinitrobenzylidene) -3-ethyl-6-nitrobenzothiazoline; (d) 2- (2,4-Dinitrobenzylidene) -1,3,3-trimethylindolenine or (e) 4- (2,4-Dinitrobenzylidene) -1-ethylquinoline. 3098 10/1035 7. Photographic material according to claim 5, characterized in that that it is an o-nitro-substituted arylidene dye 6-chloro-2- (2,4-dinitrobenzylidene) -1,3-diethyl-2,3-dihydro-1H-imidazo / ~ 4,5-b-7quinoxaline contains. 8. Photographic material according to Claims 1 to 7, characterized in that it consists of a photographic layer support consists in which the dye is distributed. 9. Photographic material according to claims 1 to 7, characterized in that it consists of a layer support and at least a binder-containing layer arranged thereon in which the dye is distributed. 10. Photographic material according to Claims 1 to 7, characterized in that it consists of a layer support and at least one silver halide emulsion layer applied thereon and containing one of the specified o-nitro-substituted dyes. 11. Photographic material according to claim 10, characterized in that that it contains a fiber of the following formula in the silver halide emulsion layer: R ₁ - Nf L = = CH-eCH = where mean: k = 0 or 1;
m = 0 or 1; 3 09810/1035 ORfQINAL INSPECTED L is an optionally substituted methine radical; R- is an optionally substituted alkyl, alkenyl or Aryl radical; Z. to complete an oxazole, thiazole, selenazole, 3, 3-I) ialkylindolenin-, imidazo / 4,5-b_7quinoxalin-, thiazoline-, pyridine-, imidazole-, quinoline-, 3H-pyrrolo- I 2,3-b_ / pyridine or thiazolo / "4,5-b ^ 7chino - linkernes required atoms, and Y to complete an optionally substituted Aryl radicals required atoms, 12. Photographic material according to claims 1 to 7, characterized characterized in that it is made from a thermal photographic recording material with (a) an image-forming layer of a heavy metal salt which acts as an oxidizing agent, a ^ Reducing agents and photosensitive silver halide and a binder composed of a polymer, and (b) an antihalation layer comprising a bleachable o-nitro-substituted arylidene dye dispersed in a binder consists. 309810/10 35 ° * «* ΝΑί. inspected