DE2430600A1 - METHOD FOR PRODUCING A PHOTOGRAPHIC POSITIVE IMAGE - Google Patents

Description

pn

CIBA-GEIGY AG, CH-40Ö2 Basel """ ■ -'- '" - ""'

Case 8-8857 / TEL 139 +

GERMANY

Lawyer file 15 * 109 . June 26, 1974

Method of making a photograph

positive image. '

The invention relates to a photographic silver complex diffusion transfer process, in which the development of an exposed silver salt containing, light-sensitive layer of a photographic recording material undeveloped silver salt aufweine, an image-receiving layer containing a silver precipitating agent is transmitted.

The production of photographic images by means of a silver complex diffusion transfer process is known for example from the German patent specification 887 733. The usual silver complex diffusion transmission

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process is based on the fact that undeveloped silver salt, in particular silver halide, an exposed photographic layer, in particular silver halide emulsion layer, in the form of a silver complex is transferred imagewise to an image-receiving layer, which contains a silver precipitating agent or silver precipitation nuclei. According to the known silver complex diffusion transfer process In particular, positive images can be generated in the image receiving layer. The image receiving layer consists usually from a binding agent in which the silver precipitating agent, e.g. germs from metal sulfides, such as nickel sulfide or silver sulfide, or a metal present in colloidal form, such as silver, gold or palladium, is dispersed.

The production of images that meet all requirements by means of the silver complex diffusion transfer method difficult for several reasons. For example, the Implementation of the silver complex diffusion transfer process mostly yellow-brown or brown-tinged in the receiving layer Received pictures. In particular, it is difficult to obtain images with neutral black tone when the image receiving layer consists of certain binders, in which

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where the silver precipitation nuclei are dispersed.

Protein colloids, e.g. gelatin, have proven to be special proven suitable binders for dispersing silver precipitation nuclei. It has been shown, however, that when used of proteinaceous colloids as binders for the silver precipitation nuclei images are obtained through are yellow-brown to light brown in color.

There has therefore been no lack of attempts to improve the known silver complex diffusion transfer process, with the aim of producing images with a neutral to blue-black color tone to obtain.

Thus, it is known to add the image receiving layer so-called toner or toning agent, which cause at der.Durch- ₌ the Silberkomplexdiffusionslibertragungsverfahrens guide neutral black tone images can be obtained even when used for preparing the image receiving layer proteinaceous binders such as gelatin. Organic thiol compounds (mercaptans) are particularly important as toning agents.

However, it has been shown that organic mercapto compounds as a toner in image-receiving layers when the material is stored, especially under tropical conditions,

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become effective when the image-receiving layer organic crosslinking agents to crosslink or harden the proteinaceous Contains colloids. The addition of organic crosslinking agents to the binder has the known advantage that the receiving layer when performing the silver complex diffusion transfer process swells less than a layer produced in the same way that does not contain a crosslinking agent contains.

There is only a slight swelling of the ... reception layer Desired for reasons: image receiving layers with little swelling take in performing the silver complex diffusion transfer process little processing liquid and therefore dry quickly, furthermore the diffusion paths are at low swelling for a short time, whereby a good resolution, high image sharpness and short diffusion times are achieved. Further, a hardened colloid layer, i.e., a colloid layer containing an organic crosslinking agent, is less easily damaged by mechanical effects as an uncured layer.

Image receiving layers for the silver complex diffusion transfer process, which consist of a swellable, hydrophilic

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Colloid, a silver precipitating agent, one useful as a toner organic thiol compound and an organic crosslinking agent exist, result in neutral black or blue-black In the course of the storage of such layers, however, the toner becomes ineffective, so that only yellow-brown or brown-black images are obtained.

The aim of the invention is to provide a method for the production of Reception layers to be realized through high storage stability distinguish.

The invention is based on the surprising finding that image-receiving layers, consisting of a silver _{precipitating agent y} a swellable, hydrophilic colloid, a toning agent and an organic crosslinking agent, are obtained with high storage stability if the toning agent is one or more heavy metal compounds of a mercaptan (an organic thiol compound ) preferably a mercapto compound of a metal of groups VIII, Ib or lib or IVb of the periodic table of the elements is used. The invention therefore relates to a process for the production of a photographic positive image by imagewise exposure of a light-sensitive silver halide emulsion layer, development of the exposed emulsion by means of an alkaline solution in the presence of a developer to give a negative silver image

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and simultaneous or subsequent transfer of a soluble reaction product of the not converted to silver wrapped silver halides in a non-photosensitive image-receiving layer that was encased in a hydrophilic colloid contains organic crosslinking agent for the colloid and developing skeitne and is in contact with the the Silver compound donating layer is located.

The method is characterized in that the image receiving layer contains at least one heavy metal compound of a mercaptan, preferably a mercapto compound of a metal, the one · - of groups VIII, Ib, Hb or IVb of the periodic

System of the elements. Silver compounds are primarily used into consideration.

Examples of organic mercaptans (thiol compounds): die: .fUr the present process give suitable heavy metal compounds are in the book by A. Rott and E. Weyde "Photographic Silver Halide Diffusion Processes ", The Focal Press [1972], pages 58 to 64. Have proven to be well suited the heavy metal compounds, especially the silver compounds of the following mercaptans, which are also found in the tautomeric thione form can be formulated:

1. 2-mercaptobenzoxazole (2-benzoxazolthiol)

2. 1-methyl-1,3,6-tetrahydro-4-mercapto-1,3,5-triazine

3. l-phenyl-5-mercaptotetrazole

4. l-methyl-2-mercaptoimidazole

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5th S.

6 * 2-thiobarbituric acid (4,6-dihydroxy-2-mercaptopyrimidine)

7. 2-mercaptobenzimidazole

8. 2-mercaptonaphthalene (thio-2-naphthol)

9. .2-mercaptopyridine '

10. 2-Thiourazil (4-Hydroxy-2-Tnercapto-pyrimidine)

11. Cysteine (^ -amino-S-raercapto-propionic acid)

12. 2-Mercapto-5-amino-1,3,4-thiadiazole

13. 2-mercaptothiazoline

14. TMοsalicylsMure (2-mercaptobenzoic acid)

15. l-mercapto-2-diethylaminoethane

16. Compound of Formula

SH ^H 3 ^C

17. Compound of formula

HH C = C

N = C SH

18. 2,5-dimercapto-1,3,4-thiadiazole

19. 1-Octadecanethiol

20. Thiooxine (8-mercaptoquinoline)

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21. 1,6-dimercaptohexane

22. Bis (2-mercaptoethyl) ether

23. 2-Amino-1-mercaptobenzene

24. Thioglycolic acid ethyl ester

25. l-mercaptotetradecane

26. Thiocarbohydrazide NH ₂ -NH-CS-NH-M ₂

27. 6-Hydroxy-2-mercapto-pyrimidine-4-carboxylic acid

28. 5-Amino-2,6-dihydroxy-4-mercaptopyrimidine

29. 2-mercaptobenzothiazole

30. 1-methyl-2-thiopyridone

31. Mercaptopropyl sulfonate

32. Mercaptoethyl sulfonate

33. 3-Hydroxy-2-mercaptopyridine

34. 3-Pheny.l-thiadiazole-2,5-dithione

35. 2-Mercapto-5-methylmercapto-1,3,4-thiadiazole

36. 3-Mercapto-6-raethylpyridazine

37. N-ethylrhodanine

38. Rhodanine-N-acetic acid

39. N-phenylrhodanine

40. S-ethyl-S-phenylaminomethylene rhodanine

41. N-ethylthionoxazolidone

42. 3-Ethyl-5-anilinomethylene thionoxazolidone

43. 3-Ethyl-5-ethoxymethylene thionoxazolidoa

44. N-ethylthiazolone-5

45. 2-oxy-3-ethyl-5-anilinomethylene-thiazolidine-4-thione

46. 1-ethyl-3-phenylthiohydantione

47. l-Acetyloxyethyl-2-mercapto-5,6-dichlorobenzimidazole

48. 2-thio-tetrahydro-1,3-thiazine

49. 6-methyl-2-thio-tetrahydro-1,3-thiazine

50. 4,4,6-trimethyl-2-thio-tetrahydro-1,3-thiazine

51. 3-mercapto-4,4,5-trimethyl-4H-pyrazole

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52.SMercapto ^^ diethylSmethyl ^ Hpyrazole

53. 4,5-dimethyl-4-ethyl-3-inercapto-4H-pyrazole

54. 5-Benzyl-4j4-dimethyl-3-mercapto-4H-pyrazole

55. 3-Mercapto-5-methyl-4,4-cyclopentemethylene ^ H -pyrazole

56. 5-Mereapto-4,4,5-trimethyl-4H-pyrazole

CH-CH = CC ₀ H ₁ .

N SH C ₂ H ₅

Preferably the silver compounds are as follows

Mercaptans:

2-mercaptobenzoxazole,

2-mercapto-1-methylenimidazole, 2-mercaptopyridine,

2-mercapto-5-amino-1,3 _s 4-thiadazole, 2-mercaptothiazoline,

2-mercapto-l-tolyl-4-dimethyl-6-methylpyrimidine, 2-mercaptobenzothiazole,

2,5-dimercapto-1,3,4-thiadiazole, 2-mercapto-5-methylmercapto-1,3,4-thiadiazole, 6-methyl-2-thio-tetrahydro-1,3-thiazine

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4,4,6-trimethyl-2-thio-tetrahydro-1,3-thiazii?, ^ 30600

S-Marcapto-ö-methylpyridazine,

3-mercapto-4,4,5-trimethyl-4H-pyrazole,

5-mercapto-4,4,5-trimethyl-4H-pyrazole.

Above all, however, the silver compounds of the following mercaptans come into consideration;

3 -Mercaptο-6-methylpyridazine,
5-mercapto-4,4,5-trimethyl-4H-pyrazole, 2-mercapto-5-amino-1,3,4-thiadiazole, 2-mercapto-5-methylmercapto-1,3,4-thiadiazole.

The organic sulfur compounds described in German patents 1,111 and 1,153,991 are also used suitable.

The mercaptan compounds used according to the invention leave produced by a preferably aqueous solution of a heavy metal salt, in particular a salt of a metal of groups VIII, Ib, Hb or IVb of the periodic table with a preferably aqueous solution or suspension of the HS connection is mixed. The MetalIsal solution and / or the A solution or suspension of the mercaptan can also contain a water-soluble colloid, e.g., gelatin.

In general, water-soluble metal salts are preferred. Examples of suitable metal salts are the nitrates, sulfates, Acetates and chlorides of iron, cobalt, nickel, copper, zinc and cadmium, the acetates and nitrates of silver and of lead. The use of SiI-

Over-salting cd, e.g. silver nitrate.

oo -

co The compounds to be used according to the invention are formed

immediately upon mixing the metal salt solution with the solution or suspension of the HS compound. These conversion products are usually not isolated, but the solution or

Suspension of the formed metal-thiol compound is with advantage directly into the production of the receiving layer Coating compound used incorporated or generated directly in the coating compound.

The coating compound also contains a water-soluble, hydrophilic colloid, e.g. gelatin. However, other proteins can also be used to produce the image receiving layer, e.g., casein, zein, albumin and the like can be used. The image-receiving layer can furthermore contain gelatin and / or proteins in a mixture with other polymers compatible with these proteins.

The coating compound also contains at least one organic crosslinking agent. Organic compounds that are used for crosslinking or hardening of colloid layers are in the book by C, E. K. Mees and TH James "The Theory of the Photographic Process" 3rd edition on pages 55 to 60. Suitable hardener compounds s5.nd aldehydes, N-methylol compounds, ketones, derivatives of carboxylic acids, also carbonic acid ed er iy ate, such as pyrocarbonates, sulfuric acid esters and sulfonyl halides, compounds that contain so-called "active halogen", such as α-chlorine - and α-. Bromine ketones, epoxides, aziridines, active olefins such as divinyl sulfones, isocyanates, carbodiimides, and also acrylic acid compounds and triazine derivatives. Particularly suitable are crosslinking agents,

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DT-PS 1 234 521 DT-PS 1 547 656 DT-PS 1 720 078 DT-OS 2 133 402 DT-OS 2 309 098 DT-OS 2 309 525

described in the following publications:

(Case 4805 / E) (Case TEL 25 / E) (Case TEL 32 / E) (Case TEL 85 / E) (Case TEL 116 / E) (Case TEL 118 / E)

Furthermore, the coating composition contains for production of the receiving layers according to the invention, development nuclei or silver precipitation nuclei. Precious metal nuclei are suitable, E.g. seeds from silver, gold, palladium or platinum. Also are sulfidic germs, e.g. germs from nickel, zinc or Copper sulfide suitable. Germs made from silver sulfide have proven particularly useful.

The receiving layers produced according to the invention contain

per m layer area advantageously 0.1 to 10 g colloidal Binder. The silver precipitation nuclei are advantageously in

an amount of 0.1 to 50 mg per m layer area, which according to the invention to be added mercaptan compounds in an amount of

0.1 to 50 mg per m layer area.

In addition, the image receiving layer can contain further additives " contain, such as surface-active substances, optical brighteners, also sodium or ammonium thiosulphate, developer compounds, such as hydroquinone or l-phenyl-3-pyrazolidon .. Furthermore, the Image receiving layer also ^ gs ± £ particles, for example from

Silicic acid, bentonite, kieselguhr, glass in powder form as well Contains aluminum and silicon oxide. Finally, the layers can also contain colloidal particles of metal oxides, e.g., titanium dioxide, aluminum oxide, and the like.

In addition, to produce the inventive Image-receiving layers used coating compositions all the additives are incorporated in a conventional, known manner corresponding coating compositions for the production of image receiving layers are added and with which the image quality in the image receiving layer can be improved, for example dithiabisquaternary ammonium salts, as mentioned in the German Auslegeschrift 1 144 593. '

The image receiving layers can be used in the usual way known support can be applied, e.g. made of paper, glass, plastic, wood and the like. As particularly advantageous Layer supports have been found to be those made of paper, in particular made of baryta-coated paper. Have to be particularly beneficial In addition, paper supports that are coated with a polymeric material, e.g. polyethylene, have been found, which serves as a moisture separation layer. The polymeric material, e.g. polyethylene or another polyolefin, can be used for Be pigmented to create a white surface.

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When carrying out the process of the invention, a silver halide emulsion layer is first image-wise in the usual way exposed, whereupon the silver halide emulsion layer with a silver halide developing agent, e.g. a silver halide developing solution, is brought into contact, which contains a compound binding the silver halide complex. The emulsion layer is developed in the exposed areas, while the silver halide complexes in the unexposed areas is bound. When the silver halide emulsion layer is brought into contact with the image-receiving layer, the complex-bound silver halide diffuses image-wise into the image-receiving layer and produced here with the aid of the silver precipitating agent contained in the image-receiving layer immediately a positive image.

For developing the exposed silver salt layers of the material used in carrying out the method of the invention can use the customary known silver halide developer compounds be used. The conventionally known silver halide solvents can be used as complexing agents for the silver salt or silver salt complexing agents, e.g. sodium thiosulphate, Sodium rhodanide, ammonia and the like are used these agents are used in such a concentration that a soluble silver complex is produced, which is able to diffuse imagewise into the image receiving layer. .

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example 1

An image receiving material for the silver complex diffusion transfer process is made as follows:

7.5 g of polyethyleneimine with a molecular weight of 30,000 - 40,000 are dissolved in 600 ml of water. For this one gives a solution of 3 g of gold hydrofluoric acid, crystall. in 150 ml of water and heat the mixture to 90 ° C for 30 minutes. A deep red sol of colloidal gold forms. It is cooled to 40 ° C. and a solution of 150 g of gelatin is added in 2250 ml of water.

10 g of the gold sol are with a 40 ° C warm solution of. 6 g gelatin diluted in 175 ml water. A solution of 0.00015 mol of 2-mercapto-1-methylimidazoline, 25 ml of methanol and 15 ml of n / 100 AgNO ₃ solution is added one after the other. 10 ml of a 2% solution of the crosslinking agent are added to this mixture the formula

C ₂ H, C ₂ H ₅ - N - CH = CH - CHO C ₂ H ₅

PF

in acetone and 10 ml of a wetting agent solution.

2 With an application quantity of 60 g per m, this pouring table is made applied to a cellulose triacetate base, and after drying one obtains a. Image receiving layer for that Silver complex diffusion transfer process.

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A photosensitive silver halide emulsion is made onto a polyethylene-coated one with the addition of hydroquinone Paper base applied, - that the poured layer

2 1.5 g silver, 2 g gelatine and 0.9 g hydroquinone per m contains. A protective gelatin layer is applied over this.

gen, which contains 0.5 g gelatin per m. The light sensitive Material is exposed in contact with a step wedge and then together with the described image-receiving layer passed through an activator bath of the following composition:

Water 1000 ml

Na ^ SO- anhydrous 70 g

₂ S ₃ O ₃ anhydrous 30 g NaOH. 30 g

KBr 2 g

Sodium carboxymethylcellu-

loose 4 g

Immediately after leaving the activator bath, the two Layers brought into contact with one another and separated from one another after 30 seconds of contact time. The image-receiving layer shows a copy of the gray wedge, the low density steps also having a neutral gray image tone.

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Example 2

An image-receiving layer is produced as described in Example 1, but without the addition of silver nitrate solution (Comparative experiment).

Receiving layers produced according to Examples 1 and 2 are stored for 24 hours at 43 ° C. and 69 % rel. Air humidity conditioned and then as described in Example 1, processed together with a light-sensitive negative layer.

The image receiving layer produced according to Example 1 gives the same neutral gray image tone before and after air conditioning. The image-receiving layer produced according to Example 2, when fresh, gives neutral gray * after air-conditioning on the other hand brown picture tones. Table 1 shows the transmission spectra of the two receiving layers before and after Air conditioning were processed.

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TABLE 1

wavelength
nm Optical density D. Example 2,
air-conditioned A. Example 1, not air-conditioned
B. Example I ₅ air-conditioned
C. Example 2, not air-conditioned *) 1.88 400 2.63 2.02 420 2.70 2.10 440 2.78 2.12 460 2.83 2.12 • 480 2.86 2.10 500 2.88 2.02 520 2.91 1.96 540 2.91 1.83 560 -2.91 1.70 580 2.91 1.60 600 2.90 1.50 620 2.88 ; 1.43 640 2.86 1.33 660 2.81 1.28 680 2.77 1 * 20 700 2.73

*) A, B and C show practically no differences

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Example 3

On a polyethylene-coated paper carrier a pouring solution of the following composition applied:

60 g of gelatin are dissolved in 1750 ml of water. 0.0017 mol of colloidal silver sulfide and a solution of 0.001 mol of 2-mercaptothiazoline in 250 ml of methanol are added. Then 150 ml of y ~ ₀ AgNO2 solution, 200 ml of a 1% solution of the crosslinking agent of the formula are added with thorough stirring

H ₀ C = CH-GO-NH-CO-0-CH ₀ -CH CH ₀

2 2. _χ / 2

and 30 ml of a 3% solution of a wetting agent are added.

60 ml of this casting mixture are coated on 1 cm of the polyethylene Paper applied and dried.

A light-sensitive silver chloride emulsion is exposed

layer containing 1.5 g of silver and 2 g of gelatin per m, behind a gray wedge and leads them together with the image receiving layer through a developer bath of the. following composition:

Water 1000 ml

Sodium sulfite anhydrous 100 g

Sodium hydroxide. 14 g

Sodium thiosulphate anhydrous 30 g

Potassium bromide 2g

Hydroquinone 16 g

. l-phenyl-3-pyrazolidone Ig

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Immediately after leaving the developer bath, the both layers brought into contact with one another and separated from one another after 30 seconds of contact time. The image receiving layer shows a copy of the gray wedge with a neutral image tone. The same image tone is obtained when the image receiving layer before processing 43 ° C and 69% rel. Air humidity is conditioned for 6 days.

The same results are obtained if instead of the specified crosslinking agent

10 ml of a 10% aqueous glyoxal solution,

40 ml of a 5% aqueous solution of the compound Cl

\ μπ - / '\\ er, _A

200 ml of a 1% aqueous solution of the compound of the formula

H ₂ C = CH-CO-IqH-CO- (O-CH ₂ -CH ₂ ) _3-0 -CO-NH-CO- € H = CH

100 ml of a 2% solution (in acetone) of the compound of the formula

(CH ₃ -CH ₂ -) ₃ N-CH = CH-CHO

PF

100 ml of a 2% solution of the compound of the formula

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Ch ₂ = CH-CON-SO ₂ -NH-CO-CH = CH ₂

HN (CH ₂ CH ₃ )

50 ml of a 2% solution of the compound of the formula '

N-CH = CH-C!

.H

or

^H 3 ^C

200 ml of a 1% solution of the compound of the formula

■ Ρ HO c ® ^ CH ₂ - <H _2x 4th N N H, s \ ^ -
jC CH ₀ - _{^1, 0} CH

admits.

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- ²² - 2430B00

Example 4

The procedure described in Example 1 is followed and similar results are obtained if instead of 2-mercapto-l-methylimidazoline the same amount of another one of compounds Nos. 1 to 58 is added. Compounds No. 12, 35, and 56.

Example 5

10 ml of 0.4 molar are added to a solution of 1 g of polyethyleneimine with a molecular weight of 30,000 - 40,000 in 100 ml of water Silver nitrate solution and heated to boiling for 15 minutes, producing silver in colloidal form.

10 g of this silver sol are at 40 ° C with a solution of 6 g of gelatin mixed in 175 ml of water. Then successively a solution of 0.0001 mol of 3-mercapto-6-methylpyridazine and 10 ml n / 100 silver nitrate solution were added. 10 ml of a 2% solution of the are added to this mixture Hardening agent of the formula

CH ₂ = CH-CON-SO ₂ -NHt-CO-CH

HN (-CH ₂ CH ₃ )

and 3 ml of a 3% solution of a wetting agent and potted

this solution with an application rate of 60 g per m - on one

Polyester pad. 409883/1283

The image-receiving layer thus obtained is processed as in Example 2, and a present-day gray image is obtained. Images of the same image tone are obtained if the image receiving layer is kept at 43 ° C. and 69 % rel. For 1 week. Air humidity air-conditioned. "" ■. ·

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Claims (9)

Claims 1. Method of making a photographic
Positive image imagewise exposure of a photosensitive silver halide emulsion layer, Development of the exposed emulsion by means of an alkaline solution in the presence a developer substance to a negative silver image - "and simultaneous or subsequent transmission of a soluble reaction product of the silver halide not developed into silver into a non-light-sensitive one An image receiving layer which is an organic crosslinking agent for the colloid and in a hydrophilic colloid Contains development nuclei and is in contact with the layer donating the silver compound, characterized in that the image receiving layer contains at least one heavy metal compound of a mercaptan. 2. The method according to claim I _1, characterized in that the image-receiving layer contains a silver compound of a mercaptan. 409883/12 8 3 3. The method according to any one of claims 1 and 2, characterized characterized in that the image-receiving layer is a heavy metal compound of a mercaptan with 1 to 2 rings, including at least one five- to six-membered heterocyclic Ring with at least one ring nitrogen atom and a mercapto group bonded to this ring. 4. The method according to claim 3, characterized in that that the image receiving layer is a silver compound contains the following mercaptans: 2-mercaptobenzoxazole, 2-mercapto-1-methylimidazole, ■ ' 2-mercaptopyridine, ^ -Mereapto-S-amino-l, 3,4-thiadazole, 2-mercaptothiazoline, 2-mercapto-l-tolyl -4-dirnethyl-6-methylpyrimidine, 2-mercaptobenzothiazole, " • 2 _s 5-Dimercapto-1,3,4-thiadiazole, ^ -Mercapto-S-methylmercapto-l ^^ - thiadiazole, 6-methyl-2-thio-tetrahydro-1,3-thiazine, 4,4,6 -Trimethyl-2-thio-tetrahydro-1,3-thiazine, J-mercapto-ö-methylpyridazine, 3-mercapto-4,4,5-trimethyl-4H-pyrazole, 5-mercapto-4,4,5-trimethyl-4H-pyrazole. 409 8 83/128 3 5. The method according to claim 4, characterized in that the image-receiving layer is a silver compound contains the following mercaptans: 3-mercapto-6-methylpyridazine, 5-mercapto-4,4,5-trimethyl-4H-pyrazole, 2-mercapto-5-amino-1, 3rd, 4-thiadiazole, · 2-mercapto-5-methylmercapto-1,3,4-thiadiazole. 6. The method according to any one of claims 1 to 5, characterized in that the image receiving layer contains 0.1 to 50 mg heavy metal mercapto compound per square meter of layer surface. 7. For the production of positive photographic images by the silver complex diffusion transfer process suitable, non-photosensitive, organic crosslinking agent for the colloid in a hydrophilic colloid and image-receiving layer containing development nuclei, characterized in that it contains at least one heavy metal compound of a mercaptan. 8. Image receiving layer according to claim 7, characterized in that it contains at least one heavy metal mercapto compound the composition specified in any one of claims 2 to 5. A 09 883/1283 -.27 - - ■ 9. image receiving layer according to one of claims 7 and 8, characterized in that it is the heavy metal compound in the amount specified in claim 6 contains. 409883/1283