DE2229454A1 - PROCESS FOR PRODUCING POSITIVE IMAGES AND RECORDING MATERIAL FOR PERFORMING THE PROCESS - Google Patents

Description

PATENT LAWYERS DR.-ING. WOLFF, H. BARTELS, DR. BRANDES, DR.-ING. HERO Dipl.-Phys. Where"?

B / dö

THIERSCHSTRASSE 8 TELEPHONE: (08Π) 293297

Heg. No. I25 57?

Eastman Kodak Company, 343 State Street, Rochester, New York State, United States of America

Method of making positive images and Recording material for carrying out the method

209881/0658

The invention relates to a method for producing positive images by exposure and development of a Aufaeicimungsmaterials from a support and at least a silver halide emulsion layer applied thereon and optionally intermediate and / or top layers, and it also relates to a photographic recording material to carry out the procedure.

Process for producing positive images using photographic Recording materials with non-fogged silver halide emulsion sciiichtarx exposed imagewise and then with the help of veiling developers are already known, e.g. B. from the USA patents 2,497,875, 2,588,982 and 2,456,953, from British Patent 1 15I 3 & 3 and the Japanese Patent 29 405/68.

To carry out these known ^ / experienced recording materials with silver halide emulsion layers of the inner grain image type are used, for. B. those which contain layers of emulsions which have been produced according to the conversion technology described in US Pat. No. 2,592,250 or the technique described in British Pat. No. 1,011,062. However, it is disadvantageous that the positive images produced by the known method with respect to photographic characteristics, e.g. B. photographic sensitivity, low minimum density and high maximum density, leave so much to be desired that they are unsatisfactory in numerous photographic applications. In addition, it proves to be desirable in other cases to use developers to produce positive images , which are ahlreichen.-known method is to halogenidlöcungsmitteln liinerürornbildentwickler or those containing ßilbei '.- * In you for producing images direittposibiven ir · uaverschivierten Emulsionsschichfcen proves JE

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but disadvantageously the use of developers which are practically free of silver halide solvents, as required.

The object of the invention is to provide means and ways with the help of which positive images with respect to sensitometric Properties improved o characteristics can be produced.

The invention is based on the knowledge that the specified object can thereby be achieved in a particularly advantageous manner is that photographic recording materials are accurate defined type with unveiled silver halide emulsion layers, the silver halide grains of which are chemically sensitized on the surface in a precisely defined manner, first exposed and then developed in a precisely defined manner.

The invention relates to a method for producing positive images by exposing and developing a Recording material comprising a layer support and at least one silver halide emulsion layer applied thereon and optionally intermediate and / or top layers, which is characterized in that one

(1) First a recording material exposed imagewise, which in one of the layers contains an electron acceptor Ϊ & Ο && - a spectral sensitizing dye present in concentrations with a desensitizing effect and which has silver grains in the silver halide emulsion layer which are chemically sensitized on their surface in such a way that still

essential

none / density is generated when exposed to exposure containing them Emulsion in the form of a layer on a support

ρ layer applied in such a way that per m tra-

209881/0658

about 1.1 to 4.3 g (100 to 400 mg / squ.ft.) Silver is dropped for 6 minutes at 27 ° C in a developer of the following composition

N-methyl-p-aminophenol sulfate 2.5 g

Sodium sulfate, anhydrous 30.0 g, hydroquinone 2.5 g

Sodium metaborate (Na ₂ BpO ^ .8H ₂ O) 10.0 g potassium bromide 0.5 6

made up to 1 liter with water

is developed, and
(2) thereafter either

a) the exposed recording material in a silver halide developer developed in the presence of a fogging agent or

b) the exposed silver halide emulsion layer during development in a silver halide developer Subjects to flash treatment.

The invention also relates to a photographic recording material for carrying out the process with at least one silver halide emulsion layer applied to a layer support and optionally intermediate and / or top layers, which is characterized in that it is in at least a layer an electron acceptor with a ca-

and / methodical half-wave potential of more positive than -1.0 / or present in concentrations with a de-sensitizing effect contains spectral sensitizing dye with a cathodic half-wave potential of more negative than -1.0 and in the silver halide emulsion layer has grain surface image type silver halide grains attached to ihi-oi 'Ol) c, fL'l--.

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are chemically sensitized in such a way as to produce a density below 0.25 when exposed to light containing them Emulsion in the form of a on a support in such

ο manner coated layer that per m support surface about 1.1 to 4.3 g (100 to 400 mg / squ.ft.) accounts for silver, for 6 minutes at 27 ⁰ C in a developer of the following reduction cooperation ·

N-methyl-p-aminophenol sulfate 2.5 g

Sodium sulfite, anhydrous 30.0 g, hydroquinone 2.5 g

Sodium metaborate (Na ₂ B ₅ O ₄ .8H ₂ O) 10.0 g potassium bromide 0.5 S

made up to 1 liter with water

is being developed.

The invention achieves that positive images with improved properties. With the help of photοgraphischeη Recording materials and processes of a new type, namely using surface sensitized silver halides, can be produced, which is surprising in that all processes are known in Hegel to carry out known processes Process conditions and process steps were avoided in which the surface of the emulsion layer present Silver halides are chemically sensitized prior to imagewise exposure, if using such methods a positive reversal image should be produced, which is why recording materials with emulsion layers of the inner corribed image type are often used were used"

According to an advantageous embodiment, according to the invention, photographic before recording materials are used with an unveiled Silver halide emulsion layer used, their Over halide grains chemically sensitized in the manner cind that in imagewise exposure and development in

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a developer of the specified composition a density of 0.25, preferably 0.1, is not yet generated, and a density of at least 0.3 is obtained when the silicon superhalide grains in the form of a silver halide emulsion layer applied to a support in such a manner is that per m. support area about 3.2 to 4.3 g (300

silver
up to 400 mg / squ.ft.) / and which have the same grain size and halide composition as that of the drawing material which can be used according to the invention, but no organic electron acceptor and / or a spectral sensitizing dye present in a concentration with a desensitizing effect, exposed and in a developer of the specified Composition is developed.

According to a particularly advantageous embodiment, photographic recording materials are used according to the invention are used, the silver halide emulsion layers of which can be characterized as follows: (1) the halide component consists predominantly from bromide, (2) the unexposed emulsion layer, if they are on a layer substrate in such a quantity

ge is applied that per m of support area about 1 _r ^ * l to 4.3 g (100 to 400 mg / squ.ft.) of silver are omitted, in a surface developer, e.g. B. developed one of the specified composition, a density of less than 0.2 is formed, and (3) the emulsion layer, when applied in the specified manner to a support, exposed and then in a masking developer of the in the U.S. Patent No. 2,563,785, a Δ D value or a Dmax-Dmin difference greater than 1.0 is obtained.

According to an advantageous embodiment, these are in particular advantageously usable silver halide emulsion layers after imagewise exposure in a SiI superhalide developer developed in the presence of a hydrazine fogging agent;

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According to a further particularly advantageous embodiment, these silver halide emulsion layers are made with the above given G characteristics after imagewise exposure developed in a silver halide developer in the presence of a reactive N-substituted cycloammonium quaternary salt.

According to a further advantageous embodiment, the silver halide emulsion layers are those which can be used according to the invention Recording materials during development in one Subjected silver halide developers to an overall flash exposure.

According to a further advantageous embodiment, the emulsion layers which can be used according to the invention in image transfer systems are present and used to generate transmission images. So can these silver halide emulsion layers forming at least one layer in an image transfer film unit, in addition to the recording material has an image-receiving layer and a developer which is used for development with the silver halide emulsion layer the same can be brought into contact in such a way that the film unit by a pair of opposing, device parts capable of exerting a pressure are passed through. Preferably contains such Film unit a so-called. Selective fogging means, which is accommodated in such a way that it is after the supply the developer material comes into contact with the silver halide, e.g. B. in one of the layers of the recording material or in a breakable sleeve.

In the case of the grain surface image emulsions which can be used according to the invention it is usually any silver halide masses with silver halides, which are predominantly on the Surface of the grains are photosensitive, so that the latent

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V-

Image in so-called. Surface image silver halide developers, which are practically free of silver halide solvents, can be developed. Preferably the halide component of the silver halide consists predominantly of bromide and contains less than 30 mole percent iodide. J ^{: <} «

According to certain, particularly advantageous embodiments U

do the silver halide emulsions contain silver halide grains, jj

which are practically free of metallic doping substances or foreign (- ''

are metal ions. With "foreign metal ions" are metal ions j

that are not silver ions, and with "metallic (

DOping agents "are metals in their metallic state, V

Metal salts and metal complexes, which ^f j are not silver halides.

According to a particularly advantageous embodiment, when used in the invention oberflächenemp- ■-sensitive silver halide emulsions are those which photographic in. '' * Testing using normal test methods

lead to the following results v

If a sample of the emulsion to be tested is applied to a transparent substrate, then a light intensity ν scale a certain, between 1 χ 10 and 1 second,

while lying exposed and then ^ for 5 minutes at 18.3 ⁰ C in a developer having the composition shown below under i X (which is a "surface-type" - ^ developers are) obtained is developed, so a maximum density Γ , which is at least 2 χ as large as the maximum density of an identical test sample that is just as exposed. ■ ...

then for 3 minutes in an aqueous 0.3% potassium ferrous solution

Ricyaiiidlösung bleached at 18.3O and then 6 minutes

ten long at 20 ⁰ C in a developer of the below under X 'narrow' j

given composition (which is an "inner grain [^,

type "developer). Preferably j

the maximum density when using developer X /

at least 0.5 density units greater than the maximum ■

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Density under the specified conditions using developer Y, and / or the silver halide grains specified Emulsion exhibit a ratio of overall sensitivity to internal grain sensitivity that is greater than 5.

The developers used to perform the specified test have the following composition:

Developer X

N-methyl-p-aminophenol sulfate 2.5 g

Ascorbic acid 10.0 g

Potassium metaborate 35 »0 g

Potassium bromide 1.0 g

made up to 1 liter with water

Developer Y

N-methyl-'p-aminophenol sulfate 2.0 g

Sodium sulfite, anhydrous 90.0 g

Hydroquinone 8.0 g

Sodium carbonate "monohydrate 52.5 S

Potassium bromide 5 »0 g

Sodium thiosulfate 10.0 g

made up to 1 liter with water

The silver halides which can be used according to the invention are not fogged. Emulsions of the in photographic recording material of the type of the present invention contain minimal developable surface latent images and 5 minutes long development at 27 ° C in a developer of the first-mentioned composition (i.e. not in the just mentioned

W0668

named developers X or I) leads to a density of less than 0.4, preferably of less than 0.25.

The grain surface of the in the inventively usable Silver halides present in emulsions are usually chemically sensitized to a value below that

that is that which causes a substantial density (i.e. / a density of less than 0.25) when after exposure in a surface developer, e.g. B- a developer of the first mentioned composition, is developed and the concerned Emulsion together with one in one desensitizing effective concentration present sensitizing dye or an electron acceptor on a support

ρ is applied in such a way that per m of support area approximately 3 »2 to 4.3 g of silver are omitted. Preferably the emulsion is sensitized to a level which would result in a speed increase of at least 0.3 logE in the absence an electron acceptor or sensitizing dye, compared to a simple unsensitized silver halide emulsion comparable type, d. H. similar grain size distribution and composition

By "chemical sensitization" is meant a sensitization of the type described by Antoine Hautot and Henri Saubenier in "Science et Industries Photographiques", Volume XXVIII, January 1957, pages 1-23 and 57-65. With such a chemical sensitization three main classes have to be distinguished, namely gold or noble metal sensitization, sulfur iron sensitization, see Be using a labile sulfur atom? len YerbincUingi and the .Reductionsssensibilisierung, ie the treatment of the silver halide with a strong reducing . _% that the "Silberlialogaaid not noteworthy / er, but in the Silberiinlogenidicris ^ all or -korn the formation 1: 1 of a center from met aiii seem SiIt- ^ r causes.

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bilization from the developer composition and it will z. B. causes a comparatively low chemical sensitization when the emulsion in question in developers with a Content of p-phenylenediamine or z. B. in iodide-containing Developers should be developed.

The silver halide grains can be used in a conventionally known manner be chemically sensitized. Thus, the silver halide grains can e.g. B. be treated with naturally active gelatine, or sulfur compounds can be added, e.g. B. those of US Patents 1,574,944,

1 623 499 and 2 410 6§9, or it can Selenium compounds can be used, e.g. Such as those described in U.S. Patents 3,297,447 and 3,297,446 Type.

The silver halide grains can also be treated with salts of noble metals, e.g. B. with ruthenium, palladium, and platinum salts. Typical suitable compounds of this type are e.g. B. ammonium chloropalladate, potassium chloroplatinate and sodium chloropalladite, which are used for the purpose of sensitization in amounts which are less than those which cause a substantial inhibition of fog, as z. B. in US Pat. No. 2,448,060, whereas these compounds are used as antifoggants in higher amounts, e.g. B. in the United States patents

2,566,245 and 2,566,263.

The silver halide grains can also be mixed with gold salts be chemically sensitized, as z. As described in U.S. Patents 2,399,083 and 2,642,361. Typical suitable compounds of this type are e.g. B. potassium chloroaurite, potassium aurithiocyanate, potassium chloroaurate, gold trichloride and 2-aurosulfobenzothiazole methochloride.

The silver halide grains can also be used with reducing

209881/0650

AX

agents are chemically sensitized, ζ. B. with tin (II) salsen (see, for example, US Pat. No. 2,487,850), polyamines, 2. B. diethylenetriamine (see, for example, UCA Pat. No. 2,518,698), polyamines, e.g. B. spermine (see, for example, US Pat. No. 2,521,925) or bis (β-aminoethyl) sulfide and its water-soluble salts (see, for example, US Pat. No. 2,521,926).

The silver halide grains can also be spectrally sensitized are with cyanine and merocyanine dyes, e.g. B. those of the US patents 1,846,301, 1,846,302,

1 94-2 854, 2 112 140, 2 165 338, 2 493 747, 2 739 964, 1 990 507,

2 493 748, 2 503 776, 2 519 001, 2 666 761, 2 734 900 and 2,739,149 and described in British Patent Specification 450,958 Type.

According to certain embodiments in which the surface the silver halide grains are chemically sensitized to a value at the lower end of the stated range is, it proves to be expedient to use iodide-releasing compounds that contain silver halide recording material incorporate or use developers containing iodide ions, to achieve certain desirable image characteristics. However, chemical sensitization is up to one If carried out at a higher grade, the use of Iodide-releasing compounds or iodide-containing developers or emulsion layers as less advantageous.

To carry out the method of the invention, simple exposure and development processes can be used to produce a positive Generate image. According to an advantageous embodiment, a photographic recording material with at least a layer of a silver halide emulsion of the specified type first exposed imagewise and then in The presence of a fogging agent in a silver halide developer. According to a further advantageous embodiment is, as already mentioned, the exposed recording material during the development of a total flash

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subjected to exposure to create a positive image- * ·

In those which can be used to carry out the method of the invention Developers can either be full-image developers containing silver halide solvents, or surface image developers. According to certain, particularly advantageous embodiments, however, are those used Developer Surface developer.

The term "surface developer ¹¹ " refers to developers which visualize the surface latent image on a silver halide grain, but not to any substantial degree the internal latent image in the silver halides of an internal grain image-forming emulsion, using the conditions commonly used to develop a surface-sensitive silver halide emulsion The surface developer usually contains one of the usual known silver halide developer compounds - ^ θϊ or reducing agents, but the developer bath or the developer composition is usually practically free of silver halide solvents (e.g. water-soluble thiocyanates, water-soluble thioethers, thiosulphates or ammonia), which crack or loosen the grain in order to produce a pronounced Irmenkornbild.Sometimes it proves to be expedient to use a small excess of halide in the developer or the emulsion layer in the form of HaLo ^ young-f travel. Send compounds to incorporate, α'jcii warn larger Kengen of them usually avoided in order to avoid a considerable cracking of the grain, which is especially in view of iodide-releasing compounds

Typical, zur Ilirchführuiij ;; the. Method of the invention in iif.ii r. ^r it; owandten EntwicKLorn usable ijilborhalogenidentv / iciL I (ji-compounduii ^ on 3XiKi ■ / ,. B. Ily.jrochiuor.e, Catechixic, Ami.nof; iici »o Lo, ^ -Pyx'azoi Ldone, ascorbic acid and their Deri-

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AH

vate, reductones, phenylenediamines, or combinations thereof. The developer compounds can see the photograph Recording materials are incorporated in which, after imagewise exposure to the silver halides in Are brought into contact, but according to certain embodiments they are particularly advantageously in the developer bath usable.

The developers used in practicing the method of the invention may also include antifoggants and development restrainers of certain types, but these compounds may also contain those in the photographic material present layers are incorporated.

Typical suitable antifoggants are e.g. B. nitrobenzimidazoles, benzothiazoles, e.g. B. 5-nitrobenzothiazole and 5-methylbenzothiazole, heterocyclic thiones, e.g. B. 1-methyl-2-tetrazoline-5-thione, and aromatic and aliphatic mercapto compounds.

The emulsions which can be used in the present invention can be those used Electron acceptors, sometimes also referred to as desensitizers, or those in desensitizing active concentrations have spectral sensitizing dyes present. The concentrations at Electron acceptors or sensitizing dyes can be different, depending on the silver halide composition, average grain size, grain size distribution and other conditions. According to certain, particularly advantageous Embodiments can produce good results when the electron acceptors or sensitizing dyes monodisperse silver halide emulsions can be added. According to a further particularly advantageous embodiment are at least 3 ^ 0 mg, preferably at least 400 mg Sensitizing dye per mole of silver in a monodisperse Silver halide emulsion with silver halide grains of

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γ- -

about 0.2 microns in diameter used. It is a combination of an electron acceptor and a spectral sensitizing dye used, the spectral sensitizing dye is usually in a concentration of less than 200 mg per mole of silver.

In emulsions

In an advantageous manner, electron acceptors can be used, which are compounds with a reduction potential or cathodic see Half-step potential (E ^) more positive than -1.0, i.e. H. z. B-from -0.40 or -0.2. In some literature references, compounds of this type are also referred to as desensitizers . Typical suitable electron acceptors also have an oxidation potential or anodic half-wave potential more positive than +0.4, preferably more positive than +1.0.

The measurement of the half-wave potential can e.g. B. after the in in U.S. Patent 3,501,307. So z. B. the cathodic half-wave potential with

—4

Using a 1 χ 10 molar solution of the electron acceptor in a solvent, e.g. B. Methanol, which is 0.05 molar in with respect to lithium chloride, are made using a Mercury drop electrode, the ρölarοgraphische

Level half-wave potential for the most positive cathodic with E "is designated. To carry out this measurement, as Reference electrode an aqueous silver-silver chloride (saturated potassium chloride) electrode at 20 ° C can be used. Electrochemical Measurements of this type are known and are described in numerous publications, e.g. B, in Delahay "New Instrumental Methods in Electrochemistry", Interscience Publishers, New York, N.Y., 1954; Kolthoff and Lingane "Polarography", 2nd edition, Interscience Publishers, New York,

N. Y., 1952i / Elving in "Analytical Chemistry", Volume 36, (1964)

voiL
Page 2426; and / Adams in "Analytical Chemistry", Volume 30, (1958),

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λ <*

The plus and minus signs are used in accordance with IUPAG (International Union of Pure and Applied Chemistry), Stockholm Convention, 1953 ».

According to a particularly advantageous embodiment according to the invention methine dyes used as desensitizers, which are usually referred to as monomethine and / or polymethine dyes. Usually it is these methine dyes are those which can be used as electron acceptors in direct-positive silver halide emulsions are.

According to certain, particularly advantageous embodiments, polymethine dyes are used according to the invention which can be characterized in that they contain at least one core with a desensitizing action. The term "desensitizing core" denotes cores which, when they are in the form of a symmetx'i, are carbocyanine dye, a gelatin-silver chlorobromide emulsion with 40 mol% chloride and 60 mol% bromide in a concentration of 0.01 to 1.0 g of dye per mole of silver are added, causing a loss of blue sensitivity of the emulsion of at least about 80 % by trapping electrons when exposed sensitometrically and developed for 3 minutes at room temperature in a developer of the following composition:

N-methyl-p-aminophenol sulfate 2.0 g

Sodium sulfate, anhydrous 90.0 g, hydroquinone 8.0 g

Sodium carbonate, monohydrate 52.5 S potassium bromide 5 »0 g

made up to 1 liter with water

The desensitizing nuclei are preferably those which, when they are in the form of a symmetrical Carbocyanine dye in the specified V / a go-

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be tested, practically completely desensitize the test emulsion to blue radiation, ie cause a sensitivity loss of more than about 90 to 95 % to blue radiation.

In the silver halide emulsions of the photographic recording materials according to the invention, cyanine dyes can be used as a particularly advantageous class of electron acceptoron, in particular imidazoquinoxaline dyes such as are used, for example, in US Pat. B, in U.S. Patent 3,431,111. Very good results are achieved with cyanine dyes which contain an indole nucleus which is substituted in the aromatic ring in the 2-position, that is to say which is a cyanine dye with an indole nucleus, as it is, for example, in US Pat. As described in U.S. Patent 3,314-796. A useful class of spectral sensitizing electron acceptors are e.g. B. the bis (1-alkyl-2-phenylindol-3) trimethine cyanines, as they are, for. As described in U.S. Patent 2,930,694-. Another useful class of dimethine cyanine dyes of this type is e.g. B. in British Patent 970 601 described ben.

Another class of usable spectral sensitizing electron acceptors are the cyanine and merocyanine dyes in which at least one nucleus and preferably two nuclei have desensitizing substituents, e.g. B. NOo> contain, e.g. B. 3 »3 ^l -diethyl-6,6'-dinitrothiacarbocyaninchlorid, as z. B. is described in British patent specification 723 019 =

The electron acceptors or desensitizers can be in the photographic silver halide emulsions which can be used according to the invention are present in a wide variety of concentrations. However, it has proven to be particularly advantageous never to be used in concentrations of about 10 mg to about 2 g per mole of superhalide.

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-jr-

At

Typical suitable polymethine electron acceptors are ζ. Β. the following:

(1) 1.1 ^l -Dimethyl-2,2'-diphenyl-3.3 ^l - "ind.olocarbocyanine bromide of the formula

GH = GH-CH

(2) 2.2 ^l -di-p-methoxyphenyl-> 1 _S 1 ^l -diniethyl-3 »3 ^l -indolocarbocyanine bromide of the formula

CH = CH-CH

CH-

OCH,

Br ¹

(3) IjI'-dimethyl-2,2 ^1, 8-triphenyl-3,3 ^l -indolocarbocyaninperchlorat of formula

CH = CH-C

ClO,

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-yf-

(4) 1,1 *, yyy'-

chloride of the formula

C = CH-GH = GH-C

Cl '

Furthermore, z. B. the following compounds are suitable:

Phenosafranine, pinacryptol yellow, 5 ^ m-nitrobenzylidene rhodanine, 3-ethyl-5-m-nitrobenzylidene rhodanine, 3-ethyl-5- (2,4-dinitrobenzylidene) rhodanine, 5-o-liitrobenzylidene-3-plienylnodanine, 1 ', 3- Diethyl-6-nitrothia-2'-cyanine iodide, M- ltitro-6-chlorobenzotriazole, 3 _? 5 '-Dietnyl-6,6' -dinitro-9-plienylthiacarbocyanine iodide, 2- (£ -dimethylaminoplienyliminomethyl) benzothiazole ethoethyl sulfate, crystal violet, 3 »3 '" * Diethyl-6.6 ^l dinitrothiacarbocyanine ethyl sulfate, 1', 3-diethyl-6-nitrothia-2'-cyanine iodide, 1,3-diamino-5-methylpllenazini1lIIl chloride, ^ -nitro-ö-chlorobenzotriazole, 3>3'-di-p-nitrobenzylthiacarbocyanine bromide, 3 _? 3'-di-p-nitrophenylthiacarbocyanine-oodide, 3,3'-di-o-nitrophenylthiacarbocyanine-perchlorate, 3 * 3 * -pearthyl-9-trifluoromethylthiacarbocyanine-iodide, 9- (2,4 ~ dinitrophenylmercapto) -3 , 3'-diethylthiacarbocyanine iodide, bis (4,6-diphenylpyryl-2) trimethine cyanine perchlorate, anhydrο-2-ρ_-dimethylaminophenyliminoniet] iyl-6-nitro-3- (4-sulfobutyl) benzothiazoliijm-hydroxyd, 1- (2-Benzothiazolyl) -2- (p_-dimethylaminostyryl) -4-, 6-diphenylpyridinium iodide, 2,3 »5-triphenyl-2H-tetrazolium chloride, 2- (4-iodophenyl) -3 - (^ -nitrophenyl) -5-phenylt etrazolium chloride, 1-ethyl-S-nitroquinolinium methyl sulfate and 3,6-bis ^ ~ 4- (3-ethyl-2-benzothiazole iyliden) -2-butenyliden_7- "1,2,4,5-cyclohexantetron.

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The organic compounds that can be used can also be used as spectral sensitizers in the visible range of the electromagnetic Serve the spectrum .. A particularly advantageous class of spectrally sensitizing electron acceptors are trimethine cyanine dyes that have an indole nucleus which is substituted in the aromatic ring in the 2-position and through its 3-carbon atom to the methine chain is bound. Dyes of this type are used e.g. In U.S. Patent 2,930,694 and British Patent 970 601 (as well as the Belgian patent 630 911 corresponding to this). A particularly advantageous one Class of spectral sensitizing electron acceptors are dyes that have an imidazo ^ "~ 4-, 5-b_7-quinoxalinium salt component contain, as z. B. in the Belgian patent 660,253 are described. In of these dyes is the imidazo ^ "~ 4-, 5-b_7-quinoxaline nucleus bound to the methine chain by its 2-carbon atom.

Another class of particularly useful polymethine dyes are those of the following formula 1.

formula 1

C-CH-CH-CH = Q

where mean:

R ₁ , R ₂ and R, alkyl radicals, e.g. B. methyl, ethyl, propyl or butyl radicals, or aryl radicals, - z. B. phenyl residues,

X is an anion, ζ. B. a chloride, iodide, bromide, p-toluene

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sulfonatef methyl sulfate, perchlorate, thiocyanate,
Sulfonate or bromide anion and

Q the atoms necessary to complete such a nucleus that a trimethine cyanine dye is formed, e.g. B. the atoms required to form a 6-nitrobenzothiazole nucleus, an imidazo _/ / ~ "4-, 5-b__7-quinoxaline nucleus or a pyrrolo ^ ~ 2,3-b_7pyridine nucleus, e.g. of the formula

wherein R ^, R ₁ - and R ^ represent radicals of the meaning given for R ^, R ~ and R ^. A typical, particularly useful dye of this type is e.g. B. 1,1 ', 3,3,3', 3 ¹ -Hexamethylpyrrolo _(/ "" 2,3-b__7py icLocarbocyaninsalz ^r, z. B. perchlorate.

A useful class of trimethine cyanine dyes with
Indole nuclei substituted in the aromatic ring are compounds of the following formula 2.

Formula 2

H-GH = CH-CY

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where mean:

an anion of the meaning given in formula 1,

an aryl radical, e.g. B. phenyl radical,

R _-1 ^ and

^, ο

substituted alkyl radicals preferably having 1 to 8 carbon atoms, e.g. B. methyl, ethyl, propyl, Butyl or octyl radicals, or sulfoalkyl radicals, e.g. B, sulfopropyl or sulfobutyl radicals, sulfatoalkyl radicals, z. B. sulfatopropyl or sulfatobutyl radicals, or carboxyalkyl radicals, z. B = carboxyethyl or carboxybutyl radicals and

Ϊ a hydrogen atom or an aryl radical, e.g. B. phenyl radical, or one by alkyl radicals, e.g. B. methyl, ethyl, propyl or butyl radicals, or by alkoxy radicals, e.g. B. Methoxy, ethoxy or propoxy radicals, substituted phenyl radical, or a heterocyclic aromatic radical, e.g. B. a thyrophene residue.

According to the invention, symmetrical imidazo- ^^^ - b ^^^ oxalin- ^ riniethin-cyanine dyes, in which each Core is bound to the methine chain through its 2-carbon atom. Typical suitable such dyes are e.g. B. those of the following formula 3

Formula 3

G = CH-GH = CH-C

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where mean:

X is an anion as defined in formula 1 and

Rr ₇ , R ₈ , R ^ and R ^ ₀ alkyl radicals, e.g. B. methyl, ethyl, pro

_8th
pyl or butyl radicals.

For further classes and examples of dyes with an imidazo ^ f "4,5-bJ7quinoxalinkern see the Belgian patent 660 253 is referenced.

The sensitizing dyes which can be used according to the invention are generally all known dyes, which are commonly used for the spectral sensitization of silver halide emulsions, preferably um Methine or polymethine dyes of this type. According to the invention, these dyes have a desensitizing effect Concentrations applied, d. H. in a larger amount than needed to achieve an optimal sensitizing effect in an emulsion that is only surface sensitized. According to a particularly advantageous embodiment the sensitizing dyes are in concentrations used, which usually lead to a desensitization of a surface-sensitized emulsion. According to this embodiment, the sensitizing dyes e applied at a concentration that is above that which the blue sensitivity of a using sirber bromoiodide emulsion (with an iodide content of 6 mol%) reduced by at least 0.3 logE if in one Surface developer is developed, e.g. B. in one of the following composition:

209881/0658

N-methyl-p-aminophenol sulfate 2.0 g

Sodium sulfite, anhydrous 90.0 g, hydroquinone 8.0 g

Sodium carbonate, monohydrate 52.5 S potassium bromide 5 »0 g

made up to 1 liter with water

The emulsions which can be used according to the invention are desensitizing Dyes that can be used at the effective concentrations can be characterized as spectrally sensitizing Dyes for silver halide emulsions including the ultraviolet, visible and infrared regions of the spectrum. These dyes are further characterized in that they have a reducing potential or cathodic Have half-wave potential less than -1.0 positive, i.e. H. z. B. a cathodic half-wave potential of -1.5 or -2.0. Typical suitable such sensitizing dyes have furthermore an oxidation potential or anodic half-wave potential of more positive than +0.4, preferably of more positive than +0.55.

Typical dyes of this type which can be used according to the invention are, for. B. methine dyes, e.g. B. the cyanines, isocyanines, pseudocyanines, Hemicyanines, Merocyanines, Oxanols, and Azacyanines. Usually any dye is used for spectral sensitization a silver halide emulsion can be used in low concentrations, according to the invention in high concentrations usable in the reversing systems according to the invention.

The photographic recording materials according to the invention can generally be developed in any conventionally known silver halide developer in the presence of a fogging agent in order to obtain good positive images. The fogging agents can be incorporated into at least one layer of the recording material, this layer being in w ir.ne; ^> -

209881 / 06S8

permeable bond with the silver halide emulsion layer or they can with the silver halide emulsion layer be brought into contact with the help of a separate bath, or at the same time with the developer solution, in the latter case the fogging agent is incorporated into the developer.

According to Hegel, the fogging agents which can be used according to the invention are those which are germinating or fogging Cause centers which trigger the development of the silver halide present in the unexposed areas, before they cause considerable development in the exposed areas. Connections of this type are in the Hegel itself practically no developer compounds for silver halides and are used as selective fogging agents designated. In some references they will too generally as silver halide fogging agents or nucleating agents designated. Typical suitable such selective fogging agents are e.g. B. hydrazine compounds and reactive N-substituted cycloammonium salts.

According to a particularly advantageous embodiment, hydrazines are used as fogging agents, e.g. B. Connections that described in U.S. Patents 2,588,982 and 3,227,552 Type.

According to a further particularly advantageous embodiment, these fogging agents are reactive N-substituted quaternary cycloammonium salts, such as are found e.g. B.

in the German patents. ... ... and _o

(Patent applications P 21 54 076.1-51 and P 21 54 075.0-51) as well as in U.S. Patent 3 615 615 In Hegel these are compounds of the following formula:

BAD ORIGINAL 9B81 / 06SÖ

Ν®C = CH-CH)

where mean:

Z the atoms necessary to complete a heterocyclic nucleus, this nucleus being a heterocyclic ring with 5 or 6 atoms including the
contains quaternary nitrogen atom and wherein the remaining atoms of the heterocyclic ring carbon,
Are nitrogen, oxygen, sulfur or selenium atoms,

j = 1 or 2,

a = 2, 3 »4, 5 or 6,

Χ ^θ an acid anion,

R is a formula radical, a radical of the formula

-CH

where T 1 and T p are alone alkoxy radicals or alkylthio radicals, or together those to complete a cyclic oxyacetal or cyclic
Thioacetals with 5 or 6 atoms in the heterocyclic Ace tairing mean atoms required, or a 1-hydrazonoalkyl radical, and

2Ü988 \ / 0658

222P454

R ^ is a hydrogen atom or an alkyl radical, aralkyl radical, Alkylthio radical or optionally substituted aryl radical of the phenyl or naphthyl series.

According to "certain, particularly advantageous embodiments it is the quaternary salts of the N-substituted Cycloammonium compounds to those which contain N-substituted alkyl radicals, the terminal carbon atom with a hydrazone group, an acyl group, e.g. B. a Pormylrest, is substituted by an acetyl radical or a benzoyl radical, as well as to those that have a dihydroaromatic ring core, z. B. a dihydropyridinium nucleus.

Typically, the fogging agents are in at least one layer of the photographic material in such a manner incorporated that they are with the silver halide emulsion layer in water-permeable connection, or they can with the emulsion layer before or during development, e.g. B .. with the help of a pre-bath or by incorporating the fogging agent into the developer. Preferably, however, the fogging agents are used in at least one Layer of the photographic material accommodated and in a particularly advantageous manner they are the Silver halide emulsion layer incorporated. In the silver halide emulsion layer the fogging agents are in concentrations of about 75 to 1500 mg, preferably about 90 to 1200 mg per mole of silver. These concentrations correspond It is common known practice, but in special cases there are also very different fogging agent concentrations advantageously applicable, e.g. B. when using reverse emulsions of a very specific type, of fogging agents different chemical activity or different development conditions.

Typical suitable selective fogging agents are e.g. B. 2-methyl-3- ₎ / ~ 3- (p-sulfophenylhydrazone) propyl_7benzothiazolium-

BAD ORtGJNAL 2Ü9B81 / 0658

bromide, hydrazine dihydrochloride, phenylhydrazine hydrochloride, p-methylsulfonamide-ethylphenylhydrazine, iOrmyl-4-methylphenylhydrazide, 3- (2-formylethyl) -2-methylbenzothiazolyl bromide, 3- (2-acetyl'ithyI) -2-bcnzylben ;! iJ. ^. ' j I.! υ π-1>. '..>;.!' _ ■ '. , 3- (2-Acetyläthyl) -2-benzylbenzoselenazolium bromide, 1,2-dihydro-3-methyl-4-phenyl-pyrido ^ ~ 2,1-b_7benzothiazolium ^br-i omid, 4,4'-ethylene ~ to (1,2-dihydro-3-methylpyrido / ~ 2,1-b_7benzothia- and 2-methyl-3- ^ r3-p- ¹ iitrophenylhydrazono) propyl 7 "-d_7th.iazolium- _c iodide.

The silver halide emulsions which can be used according to the invention are according to any known failure and maturation process, as are commonly used for the production of silver halide grains. Typical suitable such procedures are e.g. Bo single jet method, double jet method, using automatic proportional control means to maintain certain pAg and pH values procedures to be carried out using ripening agents, z. B. thiocyanates, thioethers and / or ammonia to be carried out using increasing flow rates The method to be carried out is described in the German patent (patent application P 21 O? 118.1-4-3) Type and nucleation process of that in the German patent. ., (Patent application P 21 12 765-1-4-3) Type.

The silver halide emulsions which can be used according to the invention. are preferably monodisperse and according to certain execution form it is in a particularly advantageous manner to coarse-grained emulsions, which after the specified in the German Patent specification. (Patent application P21 07 118.1-43)

described method can be produced. The monodisperse emulsions are the silver halide grains have practically the same diameter. In such emulsions, as a rule, they do not soften more than about

BAD ORJGiNAL

2ü9881 / 06b8

5% by weight of the silver halide grains having a particle size smaller than the mean grain size and / or not more than about 5% by number of the silver halide grains having a particle size larger than the mean grain size in diameter by more than about 40 % from the mean grain diameter. It has proven particularly advantageous to use photographic emulsions in which at least 95% by weight of the silver halide grains present have a diameter which is within 40%, preferably within about 30 % of the mean grain diameter. The mean grain diameter, i.e. the mean grain size can be determined according to conventional methods, e.g. B. after the projection method as z. B. by Trivelli and Smith under the title "Empirical Relations between Sensitometric and Size-Frequency Characteristics in Photographic Emulsion Series" in "The Photographic Journal" Volume LXXIX (1939), pages 330 to 338.

The specified uniform grain size distribution of silver halide grains is a characteristic of those present in monodisperse photographic silver halide emulsions Grains. Silver halide grains with a narrow grain size distribution are by controlling the conditions under which the silver halide grains are placed using a double jet method ens are produced, achievable. Such a method is used to produce the silver halide grains by simultaneously flowing in an aqueous solution of a water-soluble silver salt, e.g. B. of silver nitrate, as well as a water soluble halide, e.g. B. of alkali metal halide, for example potassium bromide, in a vigorously stirred aqueous solution of a silver halide peptizer, preferably of gelatin, a gelatin derivative or another protein-based peptizer. In proceedings of this type, the pH and the pAg are interrelated. Is z. B. one of these values changed while the other at a certain temperature

2Ü9881 / 0658

is kept constant, this can lead to a change in the frequency distribution of the grain size of the silver halide grains formed to lead. As a rule, however, the temperature used is around 30 to 90 ° C, the pH value up to around 9, preferably 4 or less, and the pAg up to about 9.8.

Suitable methods for preparing photographic silver halide emulsions having the required uniform particle size are described in numerous references, e.g. B. von Klein and Moisar under the title "Ia: Properties of Photographic Emulsion Grains" in "The Journal of Photographic Science", Volume 12, 1964-, pages 242-251; von Markocki under the title "The Spectral Sensitization of Silver Bromide Emulsions on Different Crystallographic Paces", in "The Journal of Photographic Science", Volume 13 »1965» Pages 85 to 89; von Ottewill and Woodbridge under the title "Studies on Silver Bromide Sols, Part I. The Formation and Aging of Monodispersed Silver Bromide Sols" in "The Journal of Photographic Science", Volume 13, 1965, pages 98-103 and by Ottewill and Woodbridge under the title "Studies on Silver Bromide Sols, Part II. The Effect of Additives on the Sol Particles" in "The Journal of Photographic Science", Volume 13, 1965, pages 104 to 107.

The recording materials according to the invention and the photographic emulsions which can be used according to the invention can contain the most varied of colloids present alone or in combination with one another as carriers or binders, and these colloids can also be present in the form of different layers. Typical suitable such colloids are hydrophilic substances, which can be both naturally occurring substances, e.g. B, to proteins, for example to gelatin, gelatin derivatives, cellulose derivatives, or polysaccharides, e.g. B. dextran or gum arabic,

2Ü9881 / O6b8

as well as synthetic polymeric substances, "for example water soluble polyvinyl compounds, e.g. B. polyvinylpyrrolidone, or acrylamide polymers "

Those in the photographic material of the invention present photographic emulsion layers and In addition to hydrophilic, water-permeable colloids, other layers can be used alone or in combination with one another also contain other synthetic polymeric substances, e.g. B. dispersed vinyl compounds, e.g. B. those in latex form, especially those which increase the dimensional stability of the photographic recording material. Typical suitable Synthetic polymers are, for example, those described in U.S. Patents 3,142,568, 3,193,386, 3,062,674, 3,220,844, 3,287,289 and 3,4-11,911. As particularly effective have water-insoluble polymers or latex copolymers made from alkyl acrylates and methacrylates, acrylic acid, Sulfoacrylic acrylates or methacrylates, and also those with crosslinking points that facilitate hardening, as well as those with recurring sulfobetaines in the Canadian U.S. Patent No. 774,054 and those of the type described in U.S. Patent No. 3,488,708 proven.

The photographic layers and other layers of the photographic Recording material according to the invention can be deposited on the most varied of conventionally known film supports be upset. Typical suitable supports are e.g. B. those made of gelulose nitrate films, cellulose ester films, polyvinyl acetal films, Polystyrene foils, polyethylene terephthalate foils, Polycarbonate sheets and sheets of the like or different resinous materials, as well as those made of glass, paper or metal. The use of a flexible one has proven to be useful Proven carrier, in particular a paper carrier, which can be partially acetylated or coated with barite and / or an oG-olefin polymer, in particular one

209881/0688

Polymer made from an oL-olefin with 2 to 10 carbon atoms, for example - © we polyethylene, polypropylene or ethylene butene copolymers.

Recording materials are used to carry out the method of the invention suitable for colloid transfer processes, how they z. As described in U.S. Patent 2,716,059; for silver salt diffusion transfer process, such as, for example, in the United States patents

2,352,014, 2,543,181, 3,020,155 and 2,861,885 will; for color image transfer methods as described in 2. B. in U.S. Patents 3,087,817, 3,185,567, 2,983,606,

3 253 915, 3 227 550, 3 227 551, 3 227 552, 3 415 644,

3,415,645 and 3,4-15,646 as well as in the German patents and . ... ... (patent applications P 20 52 I45.3-51

and P 20 52 130.6-51), and for impregnation transfer processes, how they z. B. in the United States patent

2,882,156.

To carry out the process of the invention it is possible to use recording materials which are intended for color photography, for example recording materials with a content of color-forming couplers, e.g. B. those as described in U.S. Patents 2,376,679, 2,322,027, 2,801,171, 2,698,794,

3,227,554 and 3,046,129; or recording materials, to be developed in solutions containing color-forming couplers, e.g. B. such as her in U.S. Patents 2,252,718, 2,592,243, and 2,950 are described, and so-called false-sensitized color materials such as those described in e.g. B. in the United States patent 2,763,549.

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

209881 / 06b8

example 1

A monodisperse silver iodobromide emulsion with cubic 0.2 / U silver halide grains were sulfur-plus-gold sensitized with the help of 33 mg of sodium thiosulfate per mole Silver and 6.6 mg potassium chloroaurate per mole of silver, 60 minutes heated for a long time at 18.3 ° C in order to achieve a speed increase of 1.0 logE over the starting emulsion, and then diluted and spectrally sensitized in the following way:

(1) 23.5 g (0.14 mol) of the emulsion were added with 34.8 g of a 10% gelatin solution, 64.7 g of distilled water, 1.0 g of a 12% saponin solution and 16.0 g of solvent plus dye, and then kept at 40 ^° C. for 15 minutes.

(2) A series of film samples were prepared containing 100, 200, 400 and 800 mg, respectively, of 1,3-diethyl-1'-methyl-2'-phenylimidazo _< / "" 4, hereinafter referred to as dye A , 5-b-7-quinoxolino-3 '-indolocarbocyanin iodide

(E _n »0.64: E« = greater than +1.0) per mole of silver, ο a

(3) The obtained film samples were measured for 1/25 second at 0.5 mm in a modified Bausch and Lomb spectrograph exposed and then for 6 minutes at 15 ° 0 in a developer designated below as developer A of the composition given below (which was an overall developer).

The film sample with a content of 800 mg of dye A per mole Silver showed a highly sensitive reversal image both in the blue and in the spectrally sensitized area (520 to GOO rim).

The film samples with a lower dye content showed a weak xioi '; at; i.vea picture and no veil in the unexposed

2U9B81 / 06b8 BAD ORIGINAL

teton districts.

The presence of Dye A thus caused loss of negative latent image formation as well of fogging in the unexposed areas. Increasing the development time in developer A led to higher maximum densities greater than 1.5 »with a loss of reversal sensitivity compared to the 6 minute long Development was noticeable.

The developer A used had the following composition on:

1-phenyl-3-pyrazolidone 10.0 g

Sodium isoascorbate 40.0 g

Sodium hydroxide 30.0 g

Sodium sulfite 20.0 g

1-phenyl-4-mercaptotetrazole 0.25 g

Potassium bromide 5.0 g

Potassium iodide 0.5 g

made up to 1 liter with distilled water

Example 2

A series of dye-containing film samples were prepared according to the procedure described in Example 1, with the exception that phenosafranine (E _n = -0.54; E = +1.00) was used instead of dye A. When using

C el

400 mg of phenosafranine per mole of silver in the silver halide emulsion a highly sensitive image reversal was observed (500 to 540 µm).

Example 5.

The FilapiMbc nit; <Lne; ".; Π ^ ΐιηΐί, an 400 mg of dye A per mole of silver was exposed and in one

BATH ORIGINAL

2Ü9881 / 06S8

10.0 ε 5.0 S. 75.0 S. 10.5 S. 0.02 S. 2.0 ε 15.4- ε 75.0 ε 1 Lit ei

a disguising developer of the following composition:

Hydroquinone U-methyl-p-aminophenol sulfate Na ₂ SO ₅

NaOH

5-methylbenzotriazole

p - / "" ß- (methylsulfonamido) ethyl_7phenylhydrazine hydrofluoride

Diglyc oleic acid Na ₃ PO ₄

made up to pH 11.2 with water

After 3 minutes of development at 21 ⁰ C, a highly sensitive direct positive image was obtained.

Example 4

A 0.2 / U silver bromogodide emulsion (containing 6 mol% iodide), which had been reduction-sensitized with the aid of 2 mg tin (II) chloride per mol of silver, was 1 minute long in a solution of dye A containing 0.5 mg of dye per ml of a 50: 50 mixture of methanol and water / water contained, immersed. After drying, the resulting film sample was displayed on a Bausch and Lomb step-wedge spectrograph Exposed for 1/2 second at 0.5 mm, followed by 5 minutes at 27 ° C in an obscuring developer of the in Example 3 given composition was developed. It a very high quality reversal image was obtained, the honesty of which extended from 400 to 620 nm.

Example 5

A coarse-grained one produced with the help of the double-jet process X-ray type silver iodobromide emulsion became such as

2Ü9881 / 0658

described in Example 4, reduction-sensitized and then with a desensitizing Henge (800 mg / mol Silver) to anhyclro-3-ethyl-9-methyl-3 ', hereinafter referred to as dye B - (3-sulfobutyl) thiacarbocyanine hydroxide

(E _n = -1.29; E ₀ ■ +0.73) provided.
approx

The resulting film sample was viewed on a Bausch and Lomb step wedge spectrograph Now exposed for 1/200 seconds with a slit width of 0.5 and then in a veiling Developer of the composition given in Example 3 Developed for 1 minute at 27 ° C. It became a highly sensitive, very dense, direct-positive image, the spectral sensitivity of which ranged from 360 to 640 nm,

Example 6

A coarse grain size silver bromoiodide emulsion was prepared by the single-jet method and sulfur-plus-gold sensitized by adding 2.2 mg of sodium thio sulfate per mole of silver and 0.84 mg of potassium chloroaurate per mole of silver, followed by heating at 65 ° C. for 10 minutes and then per mole of silver with 100 mg 1,1'-diethyl-2,2'-cyanine chloride (Ε _β = -1.03; E = +0.99) and 20 mg 1,1'-Mn-butyl-4,4'-bipyridinium dibromide (E "= -0.45; E => +1.0).

The obtained film sample was 1/200 seconds at 0.5 now Gap width exposed in the specified manner and then for 1 minute at 27 ° C in the concealing developer of the in Example 3 given composition developed. A highly sensitive direct positive image was obtained.

Example 7

A silver iodobromide emulsion which, according to de ^. described in Example 1 Process sulfur and gold were sensitized was 800 mg of that given in Example 1 per hol of silver ρit Dye A as well as with the lubricant 2-methyl - / "" 3-

2Q9881 / 06S8

(pj-sulfophenylhydrazono) propylJ7benzothiazolium bromide added. The resulting emulsion was then coated on a support applied, then exposed in a Bausch and LOmb-Spectrograph and then in a surface developer the following composition developed;

N-methyl-p-aminophenol sulfate 2.0 g

Sodium sulfate, anhydrous 90.0 g

Hydroquinone 8.0 g

Sodium carbonate, monohydrate 52.5 g

Potassium bromide 5 »0 g

made up to 1 liter with water

The result was a highly sensitive reversal image in the 520 to 600 nm range obtain.

Example 8

A silver halide emulsion de3 in BeLsJj LoI Λ be, -very level T ^ iR, ti -: ft per mole of silver, containing 800 mg of dye A, but no fogging agent, was applied to a layer support. The film sample obtained was exposed in a Bausch and Lomb Spectrograph and introduced into a developer of the composition given in Example 7. While the film sample was immersed in the specified surface developer, it was subjected to a total flash exposure of 10 seconds using a photolamp. The flash exposure completely obscured the unexposed areas, but not the image areas, so that a direct positive image was obtained.

Example 9

A chemically sensitized silver iodobromide emulsion des The type described in Example 1 was applied to a layer support in such a way that 4.3 g

BATH ORIGINAL

209881/0668

Silver (400 mg / sq.ft ·) was accounted for. To individual emulsion samples were the following spectral sensitizers Dyes at a concentration of 800 mg per dye Mol of silver added:

Dye name

G Anhydro-3 »9-diethyl-5,5'-dimethoxy-3 '- (3-sulfopro-

pyl) -tniacarbocyanin-hydroxyd (E _Q = -1.19; E _a = +0.62)

I) 5 ϊ 5 * -Dichlor0-3, 3 ^! »9-trietiiylthiacarbocyanine bromide (E _c = -1.06; E _a = +0.8?)

E 9-ethyl-3 s 3 '-dimethyl-if-j> \ 4 ^! »5'-dibenzothiacarbocyanine chloride (E _r , - -1.09? E _Q = +0.58)

F iualiydro-5.5 * -dicliloro-3 % 9-diethyl-3 '- (3-sulfobutyl) thiacarbocyanine hydroxide (E = -1.09; E = +0.86;

G 2,2 ', 8-triethylthiacarbocyanine iodide

H 3,3 ', 9-triethyl-5 _t 5' -dimethoxythiacarbocyanine-j 'odide

The emulsions obtained were applied to substrates, whereupon the film samples obtained were shown on a so-called Eastman 1B sensitometer exposed and then in a masking developer of the composition given in Example 3 «All 6 film samples gave highly sensitive direct positive images.

2Ü9Ö81 / 06S8

Claims (1)

222945A Claims Process for producing positive images by exposure and developing a photographic material of a support and at least one silver halide emulsion layer applied thereon and optionally intermediate and / or top layers, characterized in that (1) first exposes a recording material imagewise, that in one of the layers has an electron acceptor and / or a concentration that has a desensitizing effect contains present spectral sensitizing dye and that in the silver halide emulsion layer Has silver grains that are chemically sensitized on their surface in such a way, essential that ek- no / density is generated when the exposed emulsion containing them in the form of a layer applied in such a manner to a layer support Layer that per m of support area about 1.1 to 4.3 g (100 to 400 mg / squ.ft.) Silver accounted for, 6 minutes long at 27 ° C composition long at 27 ° C in a developer with the following ingredients N-methyl-p-aminophenol sulfate 2.5 g Sodium sulfite, anhydrous 30.0 g Hydroquinone 2.5 g Sodium etaborate (Na ₂ B ₂ O ^ -SH ₂ O) 10.0 g Potassium bromide ■ 0.5 g made up to 1 liter with water is developed, and
(2) thereafter either 2Ü9881 / 06S8 222945A a) the exposed recording material in a silicon halide developer developed in the presence of a fogging agent or b) the exposed silver halide emulsion layer during development in a silver halide developer subjected to a flash treatment. 2. The method according to claim 1, characterized in that in a silver halide developer in the presence of one Hydrazine fogging agent or a reactive N-substituted en quaternary cycloammonium salt developed. 3. Process according to Claims 1 and 2, characterized in that so-called surface image developers are used as the silver halide developer or Whole Image Developer used. 4. Process according to Claims 1 to 3, characterized in that that a recording material is used which has an electron acceptor in the silver halide emulsion layer or contains a spectral sensitizing dye. 5. Process according to claims 1 to 4-, characterized in that that a recording material is used whose silver halide emulsion layer produced a density of less than 0.25 in the specified exposure and development test. 6. The method according to spoke 1 to 5, characterized in that a recording material is used whose silver halide grains sensitized on their surface in such a way with the help of sulfur and gold sensitizers are that the emulsion containing them has a sensitivity at least 0.3 logE higher than the same emulsion in the absence of the electron acceptor or spectral sensitizing dye. 2U388 1 / 06b8 7. Photographic recording material for implementation The decay according to Claims 1 to 6, having at least one silver halide emulsion layer applied to a layer support and optionally intermediate and / or cover layers, characterized in that it is in at least one Layer an electron acceptor with a cathodic half-wave potential of more positive than -1.0 and / or a spectral sensitizing dye with a cathodic dye present in desensitizing concentrations Contains half-wave potential of more negative than -1.0 and in the silver halide emulsion layer, silver shark has οgenide grains of the grain surface image type which are chemically sensitized on their surface in such a way that a density of less than 0.25 is generated, when the exposed emulsion containing them is in the form of a layer applied in such a manner to a support 2 '/ Layer that per m of support area about 1, / to 4.3 g (100 up to 400 mg / squ.ft.) Silver is omitted, for 6 minutes at 27 ° G in a developer of the following composition N-methyl-p-aminophenol sulfate 2.5 g ITodium sulfite, anhydrous 30.0 g, hydroquinone 2.5 g Sodium metaborate (Na ₀ BpO ^ .8HpO) 10.0 g Potassium bromide 0.5 g made up to 1 liter with water is being developed. ü. Photographic recording material according to claim 7 » characterized in that the silver halide grains are chemically sensitized in such a way that a density of at least 0.3 is generated if the specified reporting3- and development test in a silver halide emulsion of the same halide composition with silver halides dernelbon grain size, which is practically free of elec- 209881 / 06B8 BAD OR.Q.NAL tron acceptors or in desensitizing effects Concentrations of any spectral sensitizing dyes present is carried out and the emulsion is in the form one applied to a substrate in such a way The same layer is tested that per m of support surface is about 3.2 to 4.3 g of silver (300 to 400 mg / squ.ft.) Are omitted. Photographic recording material according to claims 7 and 8, characterized in that the silver halide grains with the aid of sulfur and gold sensitizers are sensitized. 10. Photographic recording material according to claims 7 to 9ι characterized in that it contains a silver halide fogging agent in at least one of the layers, which is in water-permeable connection with the silver halide present in the emulsion layer _a 11. Photographic recording material according to claims 7 to 10, characterized in that the fogging agent consists of a hydrazine compound or a reactive N-substituted Gycloammoniumalz consists. 12. Photographic recording material according to claims 7 to 11, characterized in that the silver halide grains are practically free of so-called metal doping agents or foreign metal ions trapped therein. 13. Photographic recording material according to claims 7 to 12, characterized in that the halide component the silver halide grains consist primarily of bromide. 14 ", Photographic recording material according to claims 7 to 13s characterized in that the electron ac- 2U988 1 / 06b8 receptor has a catliodic half-wave potential of positive than -1.0 and an anodic half-wave potential of more positive than + 0.4-. 15 · Photographic recording material according to claims 7 "to 14-, characterized in that the spectrally sensitive Dye has a cathodic half-wave potential more negative than -1.0 and an anodic half-wave has a potential of more than + 0.4-. 16. Photographic recording material according to claims 7 to 15, characterized in that the electron acceptor consists of an organic compound with a desensitizing core. 2U9881 / 06b8