DE2038291A1 - Process for making lithographic images - Google Patents

Description

- 'DRwI NG. BY KREISLER DR.-l NG. SCHÖNWALD DR-ING. TH. MEYER DR. FUES DIPL-CHEM. ALEK VON KREISLER DIPL-CHEM. CAROLA KELLER DR.-ING. KLCTPSCH

COLOGNE 1, DEICHMANNHAUS

Cologne, July 30, 1970 Mr / Breu

EGG. du Pönt de Nemours & Company, Wilmington 19 898 Delaware, United States of America

"Process for making lithographic

Pictures "

The invention relates to a method for making lithographic Images and lithographic printing plates and activator solutions.

It is known to make lithographic images from gelatin silver images. According to an associated procedure a.exposed layer of a gelatin-silver halide emulsion treated with a tanning developer that hardens the gelatin in the exposed areas and for printing inks makes receptive. In the bromine oil process, oleophilic, Hardened gelatin images are produced by making a gelatin silver image using conventional photographic methods made, treated with a tanning bleach, the gelatin in the silver image areas of the layer hardens, while the non-silver parts of the gelatin layer are not affected. That in a gelatin silver picture Silver present can therefore be used to catalyze the oxidative degradation of the gelatin in the imaged areas, so that they leave behind a oleophilic sub-layer can be washed out.

In US Pat. No. 5,083,097 there is a method for Making a lithographic image from a gelatin silver image described, in which the silver image is converted into an image of heavy metal and / or silver compounds and those with slightly soluble organic compounds,

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contain the -SH, -SeH, -OH or -NH groups, to form organic, salt-like or complex compounds that are less soluble than the original Oxidation products. The presence of the organic, salt-like or complex-like compounds makes the illustrated Image areas are oleophilic and accordingly receptive to printing inks. In this process, that becomes The entire superficial silver image is converted into a silver salt in the first process stage, while in a second Process stage of this silver salt further with a slightly soluble) organic compound is reacted to form the oleophilic image.

The disadvantage of the known methods is that they require a lot of time and are difficult to perform, they produce disks that are only proportionate print a few copies before they wear out.

The object was therefore to provide a method for producing lithographic images which can be carried out easily and results in very durable images that can be used to print thousands of copies.

The improved lithographic images of the invention include a hydrophilic colloidal binder which is able to form a complex with copper (l) ion and an insoluble complex compound or a salt of copper (I) ion with an oleophilizing compound form.

The invention is based on a method for producing lithographic images, in which a photographic Material composed of a layer support with an overlying layer composed of a dispersion of a photosensitive , Silver halide exposed imagewise in a macromolecular, organic protein colloid binder,

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the exposed layer was developed with a developer for silver halide to form a silver image, and the developed Silver image treated with an aqueous solution containing

a) a water-soluble, inorganic copper (II) ion forming copper salt in an at least 0.01, preferably about 0.01 to 2.0 molar concentration,

b) a water-soluble, inorganic halide in a molar concentration of 0.01 to 5> preferably 0.01 to 0.5 »which provides a halogen ion to form a silver salt which is not more soluble in water is as silver chloride,

to reduce copper (II) ions, the reduction being completed before the entire superficial silver image is oxidized. It is characteristic that an oleophilic compound is present at least when the Material is treated with the aqueous solution or after the formation of the cup. - (I) ions.

The lithographic images are described in simple terms and how Usually formed by treating a colloidal silver image with a solution, the copper (II) ions and the sulfur or nitrogen-containing, oleophilizing organic Contains compound and this treatment continues until the metallic silver enough copper from the divalent Has converted the state into the monovalent state, i.e. has reduced enough copper (II) ions to copper (I) ions, which form an insoluble complex compound with the oleophilizing organic compound to form printing inks to generate a receiving image. This treatment should be stopped before the entire superficial silver image has reacted with copper (II), so that the remaining silver is the metallic silver component of the lithographic

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Image can deliver. The oleophilic compound can, as indicated, also according to fig be added.

In order to obtain the lithographic images, the manufacturing process Activator solutions used. The activator solutions represent according to one embodiment of the invention an aqueous solution with a pH of 0.5 to 6.0, preferably between 1 and 3, represent and contain

a) copper (II) ions in a concentration of at least 0.01 molar, preferably up to about 2.0 molar,

b) a water-soluble, inorganic halide in a molar concentration of 0.01 to 5 »in particular 0.01 to 0.5, which provides a halogen ion to form a silver salt which is not more soluble in water is as silver chloride,

it is important that the activator solution at least contains any of the following:

1.) an oleophilic compound in a concentration of 0.1 to 10 g or more per liter of solution,

2.) a mild oxidizing agent in such a concentration that the ratio of copper (II) to oxidizing agent is between 1: 5 "and 100: 1.

Useful oleophilizing compounds are below described. Suitable mild oxidizing agents that may be present in the activator solution, either in combination with the oleophilic compound or not are, for example: iron (III) ions, benzoquinone, mercury (II) chloride in a concentration ratio to copper (II) ions from about 5/1 to 1/100, preferably from 3/1 to 1/30. It has been found that such oxidizing agents

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Reduce the formation of substrate foam on the panels or switch off.

Citric acid and other complexing substances can be used to achieve the accessible concentration of copper (II) ions to regulate. Other auxiliaries, such as 1,2,3-triphenylguanidine and cyanoguanidine, the Aktiv.atorlaaing can can be added to make the plate stable more quickly.

The invention makes lithographic plates available which can be used very quickly on the press for printing and show a long life in the press, so that you can make up to 30,000 copies or more with a single Plate can produce.

The hydrophilic binder for the lithographic images is a layer of a film-forming colloid, which has chemical groups capable of forming complex compounds or salts with copper (I) ions and in this way binds them to the layer. A preferred binder is gelatin, albeit any hydrophilic Binder is applicable, which is capable of a strong complex compound or a salt with the copper (I) ions for example other macromolecular proteins including casein and zein.

The binder should preferably form stronger complexes with copper (I) ions than with copper (II) ions. That In addition, the binder should be sufficiently hardened so that no colloid overflows onto the printed surface will.

The copper (I) ions imagewise distributed in the ink receptive areas of the lithographic image can pass through each to form a copper (I) ion image suitable funds are generated. One

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Copper (I) solution can be applied mechanically, e.g. with a pen or an engraving printing press.

A particularly preferred method of production. of a copper (I) ion image consists of copper (I) ions by imagewise reduction of copper (II) ions using a metallic silver image as a reducing agent to create. For this purpose, the colloidal silver image is treated with an aqueous solution of Copper (H) ions in a concentration of at least 0.01 mol to about 2.0 mol per liter and a suitable one Anion, for example a halide, which forms a silver salt that is not more soluble in water than silver chloride, and in a concentration of about 0.01 to about 0.5 molar, preferably between 0.01 and 0.1 molar, is present.

The metallic silver component of the picture is for one long life of the lithographic image is required. In the absence of metallic silver, the lithographic image deteriorates fairly quickly.

A preferred procedure for producing the metallic silver in intimate association with the copper (I) ion image consists in creating this image by using a metallic silver image for the reduction of copper (II) ions is used and interrupts the process before the entire superficial silver image is oxidized. This leaves reach each other by stopping the reduction wäfepeüd, while at least some of the silver image is still visible.

The one either present in the activation solution or oleophilizing compound added following the reduction of copper (II) ions constitutes a compound which forms an insoluble salt or a complex compound with copper (I) ions while it forms with copper (II) ions a considerably more soluble complex compound or

■ I

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Forms salts and at the same time the hydrophilic, colloidal Binding agent gives an oleophilic character. In general, the molecules of such compounds have one oleophilic part and a copper complex or salt-forming part. The copper complex compounds or salt-forming part often contains one or more nitrogen, sulfur or oxygen atoms. On the other hand, the oleophilic part often exhibits a hydrocarbon residue. Generally speaking, Je The more soluble the compound is in water, the more effective it will be, since larger concentrations of the molecules are used to react become accessible with the copper (I) ions.

According to one embodiment of the invention, the organic compounds contain at least two heteroatoms in order to achieve the To be effective in producing an oleophilic, ink-receptive image. Compounds containing nitrogen are usually most effective, but sulfur and oxygen containing compounds can also be used. Compounds to be used with preference are: Substituted organic Indoles, diazoles, triazoles and tetrazoles. According to one embodiment of the invention, potassium thiocyanide is used here, Benzotriazole, 2-mercapto-thiazoline, 6-nitrobenzimidazole, 3-amino-l, 2,4-triazole, tannic acid, potassium hexacyanoferrate- (II) and potassium hexacyanoferrate Clll).

In practicing another preferred embodiment of the invention, a conventional gelatin-silver halide photographic emulsion is used exposed to actinic rays by a process transparent and then exposed in a usual Latent silver halide image developer designed to produce a metallic silver image. That developed image is then treated in a bath for 5 to 90 seconds, the copper (II) chloride or bromide in one concentration between 0.05 and 0.5 mol / liter and citric acid in a concentration of 0.01 to 0.25 mol Oe liter

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and an oleophilic compound, for example Benzotriazole, in a concentration of 0.1 to 10 g or more per liter. Treatment should be stopped before the entire superficial silver image is oxidized. Mach this treatment is then the lithographic Plate placed on a press, colored with lithographic ink and used for offset or printing directly related to negative lithographic copies of the original.

The following examples illustrate the invention.

example 1

An ortho-sensitized gelatin-silver chlorobromide emulsion with 70 mole percent bromide and 30 mole percent chloride, which is 111 g Gelatin / mole of silver halide, was adjusted to a layer weight of 88 mg / dm silver halide applied to a carrier film made of polyethylene terephthalate, prepared according to Example 4 of TJSA Patent 2,779,684. The dried emulsion was then coated with an abrasion protection layer made of gelatin, setting a layer weight of 2.5 mg / dm gelatin layered. A sample of this material was then made Exposed for 10 seconds through a negative halftone and line original with a No. 2 EFL photo floodlight lamp, which in was kept at a distance of 0.61 m and operated at 22 volts. The exposed sample was 30 seconds at 27 ° 0 with a common p-methylaminophenol / hydroquinone developer of high pH developed in a bath of 15 sec 2% acetic acid and then 30 seconds in an activator solution from pH 2 to 6, which was prepared as follows.

First, solutions A and B were prepared.

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Solution a

3 molar aqueous potassium bromide solution 100 ml

3 molar aqueous copper (II) nitrate solution 100 ml

1 molar aqueous potassium citrate solution 50 ml

What s he ι. Remainder to 1000 ml

Solution b

Benzotriazole solution (1 g / 20 ml ethanol). 10 ml Water . 990 ml

Solution B was added to solution A. The plate was then rubbed off with a standard rubber-asphalt emulsion, such as those commercially available and for lithographic treatment Plates is known. Then black offset lithographic ink was used using a moistened with 2% acetic acid Schwabbers colored. The plate was then placed in an office machine for offset copies for printing several hundred offset copies on hard paper used, with 2 - $ ~ Acetic acid was used as the wetting solution.

Example 2

The samples of the material of Example 1 were 15 sec. At 24 ° C in a standard l-phenyl-3-pyrazolidone / hydroquinone ^ High pH developer developed in white light, bathed in 2% acetic acid for 15 seconds and with treated with an activator solution of the following composition:

. 3 molar aqueous potassium bromide solution 100 ml 3 molar aqueous copper (II) nitrate solution 50 ml Water 850 ml

The treated test strips were in baths of Test solutions for the various compounds listed in Table I. treated, with black lithographic printing ink and rubbed with the help of a buff that is moistened with

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It

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solution of the following manufacturing method was soaked through.

Initial humidification solution:

3 molar orthophosphoric acid solution IO ml

0.5 iaolar trisodium phosphate solution 25 ml Water: remainder to 1000 ml

Usage humidification solution:

Initial humidification solution:. 20 ml

Gum arabic (1 g / 100 ml ethanol) 10 ml

Diethylene glycol monobutyl ether 50 ml

Remainder: water to 1000 ral

Other conquest strips were made using a buff checked, which had been moistened with 2% acetic acid. The test solutions were prepared by dilution of 5 ml of a concentrated solution of the selected Connection with 95 nil water. The results of the Ink pickups are listed in Table I.

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Panel I.

link

Concentrated solution

Solution Henge middle

Print color pick-up

2 % vinegar
acid Humidification
tion
solution
of
Example 2 there there there no there no there no there there there no there no there there there no there no there there there no there no there there there no there no there no there there there no there no there no there no there there there there there there there there there no there no there there

Benzotriazole 3,5-dimethyl-1,2,4-triazole 6-IIitrocb.inolin 2-mercaptobenzinidazole 5-Nitrobenzotriazole 2-Hercapt topzoxazole Thioglycolic acid, thiobarbituric acid, 1,2-haphthotriazole 2-mercaptobenzothiazole 6-nitrobenzimidazole nitrate Phenolphthalein 2-mercaptoethanol 2-mercaptothiazoline 2-mercapto-4-phenylthiazole l-phenyl-5-mercaptotetrazole 3-ethylrhodanine tolutriazole 4-phenylc at echol 2-chlorobenzothiazole Thi ο ε alicylic acid Tetrachlorohydroquinone-2-ethanol 1 g / 100 ml

Il M

amino-6-methylbenzothiazole Il Il 3-amino oil-1,2,4-triaalol Il Il Potassium Hexacyanoferrate- (11) water 11 Kaiiumh exacyanoferrate- (III) Il η Guanidine thiocyanate Il ti Congo red ti Il Sodium thiosulfate Il H Kaiiurathiocyanate Il It

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- 12 Continuation of panel I

link

Concentrated solution;

Solution amount
middle

Printing ink on the outside of the tube 2 % vinegar, odor acid solution
Example 2

5-aminotetrazole monohydrate water 1 g / 100 ml yes

Methyl-7-hydroxyl-1,2,3-triazol-indolizine

6-nitroindazole

0.26n ~ NaOH 5.2 g / 100 ml

20% ethanol / 0.2 n-

1 -Ph eny 1 -J -ät hyl -2 [ß-ethylbenzothiazolpropylidine] -benzimidazoliumdodid

no

β atm χ g / j-uu m ± oa no 5-ltitroindazole It ti there no Guanidine O, 2n-FaOH 1 g / 200 ml there there Ethylene thiourea 50% etha
nol / water 1 g / 100 ml there there Hypoxanthine .0.007n-: Wa0H It there no 3-chloro-6-nitroindazole Ethanol Il there no Hexamethylenetetramine water ti there no Phenyl isotmocyanate ithanol ti there no 2,4,5-triphenylimidazole It dd there no 2-guanidine benzimidazole Il It there no 2-aminobenziraidazole It It there no ω, ω ¹ -bis-piperidinemethyl-
urea Water ti there no Pentamethylene tetrazole Ethanol dd there no DL-ß-ph enylalanine 1% vinegar ~
acid ti there no Histamine dihydrochloride water ti there no L-histidine ti It there no 1,10-phenanthroline Ethanol It there . no Dihy dr o ^ nonänph enon It ti there no 1,2,3-triphenylguanidine Il Il there no l-phenyl-2-methyl-
benzimidazole ¹¹ 1 g / 1000 ml there no 2-methyl-1,3-diethyl
benzimidazole iodide 11 dd there no

no

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Continuation of panel I

Compound Concentrated ink absorption

2 % vinegar

Solution amount acid solution solution. medium . of the example p.2

3,1'-disulfopropyl

5-methyl-2-baEothia-

zol-2-quinoline cyanine ethanol lg / 500 ml d ^a no Remazol Brilliant

Blue (OI Reactive
blue 19) water lg / 100 ml yes no Stilbene Yellow

(G.I. Direct Yellow 11) "" yes no

Concentration product
ν. Sodium bisulfite and the like
a polyacrolein resin
from the molecular weight
400,000 (atomic ratio of carbon:
Sulfur = 6) water "yes no

Tannic acid "" yes

Example 3

A sample of the material of Example 1 was taken from the support side in contact with a halftone negative transparency 10 sec. with a No. 2 RFL photo floodlight lamp exposed, which worked at 20 volts and was kept at a distance of 0.61 m. The exposed sample was 1 min. In a usual High pH p-methylaminophenol / hydrochinoii decelerator developed, washed for 5 min. with water and then for 2 min. in a bath made from a solution of the following composition treated to make a lithographic printing plate:

3 molar aqueous copper (II) nitrate solution 5 ml

Glacial acetic acid 1 ml

3 molar aqueous sodium chloride solution 5 ml

1 molar aqueous potassium acetate solution 10 ml

Kaliurathioacetat "(0.1 g / ml aqueous solution) 4 ml

Wasoer 109810/1498 65 ml

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0.3% aqueous colloidal SiO ₀ -SoI with a

Content of 30% by weight SiO ₂ 10 ml

Water 100 ml

Using 1% acetic acid as a dampening solution, hard paper was printed on with the aid of an office copier printed lithographic offset copies.

Example 4

A sample of the material from Example 1 was imagewise exposed for 1 minute in a conventional 1-phenyl-3-pyrazolidinone / hydroquinone developer Developed from high pH, 15 sec. in a bath of 2% acetic acid solution and then Treated for 30 seconds in an activator solution with the following composition:

3 molar aqueous solution of copper (II) nitrate 10 ml

3 molar aqueous potassium bromide solution 10 ml

1 molar orthophosphoric acid solution 5 ml

Potassium thiocyanate (0.1 g / ml aqueous solution) 4 ml

Sodium nitrite (50 g / l aqueous solution) 5 ml

Water 71 ml

Using a dampened buff, the sample was then rubbed with lithographic printing ink. Of the the imaged part of the sample accepted printing ink.

Example 5

A test piece of the material of Example 1 was 30 seconds in part. At 20 ⁰ C when the white Eaumlicht in a conventional p-riethylaminophenol / hydroquinone Entxvickler of pH high submerged. Excess developer was removed by squeezing off and the sample was treated for 15 seconds in a bath of an activator solution which had been prepared as follows:

First, solutions A and B were made:

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Solution A

3 molar aqueous citric acid solution 20 ml

3 molar aqueous tartaric acid solution 20 ml

Benzotriazole solution (lg / 100 ml ethanol) 20 ml

Water, 40 ml

Solution b

3 molar aqueous potassium bromide solution 10 ml 3-polar aqueous copper (II) nitrate solution 5 nl Water - 85 ml

Solution B was added to solution A.

The treated coupon was then lightly squeezed against the emulsion side of another coupon of the material of Example 1 and held in contact for 4-5 seconds. The sample strips were then separated from one another and the undeveloped strip was rubbed with a lithographic printing ink using a cotton swab moistened with 2% acetic acid. That part _: the receiving layer, which had been in contact with the developed area of the first sample strip, received ink.

Example 6

A gelatin-silver image was produced on a polyethylene terephthalate support film using the material of Example 1 by conventional photographic means. The gelatin silver image was treated in an aqueous copper (II) bromide solution for 10 seconds and then brought into contact with a sample of the material from Example 1, which had also been moistened with activator solution, for 10 seconds, followed by separation. The receiving layer was soaked in an aqueous benzotriazole solution for 10 seconds and lithographic printing ink was rubbed in using a cotton swab moistened with 2% acetic acid. The receiving layer had an ink-receptive image.

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Example 7

By fixing, washing and drying an undeveloped !! Sample of the material of Example 1 became a cured one Receiving layer made of gelatin on a polyethylene terephthalate support manufactured. Example. 6 was then using this receiving layer instead of the one from Gelatin-silver chlorobromide existing receiving material same example repeated. An image that accepts printing inks was obtained on the receiving layer ».. ■■■

Example 8 '...

A photographic, highly sensitive gelatine silver product - bromide emulsion of the X-ray type with a "veraaltaiis of- ' 3 mol .-% iodide to 97 mol .- # bromide, the 120 g gelatin each Mole of silver halide, was, with adjustment, a A layer weight of 110 mg / dm silver halide was added Polyethylene terephthalate support provided with an underlayer of Example 1 applied. The dried emulsion was rubbed off with a gelatin abrasive compound

layered, which had 10 mg / dm gelatin -! dead ver, Using this material as a photosensitive layer, Example 5 was repeated. On the receiving rail "was obtain an image that accepts printing inks.

Example 9

A sample of the material of Example 1 became imagewise; exposed, developed and as in photographic practice usual fixed. The gelatin silver image obtained and one A sample of the material from Example 1 was treated for 10 seconds in a bath from a solution of the following composition:

3 molar aqueous copper (II) nitrate solution 5 ml

3 molar aqueous potassium bromide solution IO ml

3 molar aqueous citric acid solution 10 ml

Water ■ · "■ '75 ml

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The treated test strips were mutually for 20 seconds Baeached in Söntalct and then separated from each other. That Receiving material was made from solution in a bath for 15 seconds the following composition:

(Ig / 100 ml alcohol) 10 ml

aqueous citric acid solution 10 ml Vasser 80 ml

The Saapfaaagsfolie was then using one with 2 3r-igei ?, containing a small amount of gum arabic Acetic acid moistened cotton swab with lithographic Ink rubbed in. It was created on the

a black ink image.

Example 1Ό

A hardened gelatin receiving layer on a polyethylene terephthalate support was produced according to Example 7. Example 9 was repeated using this receiving layer instead of the gelatin-silver chlorobroaid receiving material of this example. A black ink image was obtained on the receiving material.

Example 11

A sample of hardened gelatin on a polyethylene terephthalate & aXat support, which had been prepared according to Example 7 was 30 seconds in a solution Copper- (XI) -brtsniid soaked and then 30 seconds in one Benzotriazole solution soaked in a small amount Natriuraiitrite had been added. The treated sample was then rubbed with lithographic ink using one moistened with 2% acetic acid Scbwabbers. The gelatin proved to be absorbent for printing ink.

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Example 12

100 ml 100 ml 100 ml 50 ml 25th ml 25th ml

A sample of the material from Example 1 was exposed and further treated as indicated in Example 1, however instead of the activator solution of Example 1 one Activator solution with the following composition was applied:

Glacial acetic acid

Benzotriazole (1 g / 100 ml alcohol) 1 molar aqueous potassium citrate solution 3 molar aqueous potassium bromide solution

3 molar aqueous copper (II) nitrate trihydrate solution

1 molar aqueous iron (III) nitrate nonahydrate solution

1,2,3-triphenylguanidine (1 g / 100 ml alcohol) 50 ml Water: remainder to 1000 ml

When used in accordance with Example 1, the plate produced good offset copies which showed no background foam.

Example 13

A highly sensitive, ortho-sensitized gelatin silver iodobromide emulsion with about 1.2% silver iodide, the had about 120 g gelatin per mole of silver halide on a 0.20 mm water-tight, polyethylene-coated photographic support with adjustment of a layer weight of 27 mg / dm silver bromide applied and coated with 10 mg / dm hardened gelatin, which with 4 g formaldehyde 100 g of gelatin each had been hardened.

A sample of this material was printed on a collotype jig exposed, in which each letter works separately using a xenon flash tube Light source that was exposed to a flash

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ICX) ml 100 ml 100 ml 250 ml 250 ml 1000 ml

duration of 2 to 3 microseconds and an energy output of 100 millijoules worked. The developed sample was 30 seconds in a standard l-phenyl-3-pyrazolidone / hydroquinone developer, which contained 0.25 g benzotriazole per liter, shell-developed, washed with water for 30 seconds and in an activator solution of the following composition for 30 seconds treated:

Glacial acetic acid

Benzotriazole solution (1 g / 100 ml ethanol) 1 molar aqueous potassium citrate solution 0.6 molar aqueous potassium bromide solution

0.3 molar aqueous copper (II) nitrate solution

Water: rest too

The sample was then washed with water for 30 seconds and rubbed with a commercially available asphalt-rubber emulsion for panel treatment. D _a nn the plate was placed in an office copying machine and offset t.iigewandt as dampening solution manufactured follows to the pressure of 30, 000 copies using a.

Auspangs-Humidification solution;

3 molar phosphoric acid 10 ml

0.5 molar aqueous trinatriuric phosphate

solution 25 ml

Remainder: water to 1000 ml

Usage humidification solution

Initial moistening solution 20 ml

Benzotriazole solution (1 g / 100 ml ethanol) 10 ml

Gum arabic (lg / 100 ml water) 20 ml

Diethylene glycol monobutyl ether 50 ml

Remainder: water to 1000 ml

All copies showed good quality offset images.

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Example 14

A highly sensitive, ortho-sensitized aqueous gelatin silver Iodobromide emulsion was coated with polyethylene with a layer thickness of 25 mg / equivalent AgBr / dm coated, equipped with a gelatin adhesive layer, Waterproof backing paper applied with low intensity red safety light. About the damp Emulsion layer was an abrasion protection layer made of gelatin, which contained formaldehyde as a hardening agent, at 15 mg /

dm applied and the two layers dried. A χ 25.4 38? 1 cm sample piece of the paper coating was soaked 1 min. At 22 ⁰ C with 1000 ml water containing 10 g of benzotriazole and 1.5 g of the sodium salt of p-tert-Octylphenoxydiäthylenglykolsulfonsäure contained. After air drying, the test piece was passed through a test template in a vacuum frame with a KScM-100-watt, 20-volt, WoIframfaden-Punktlicht-GHühlampe at 114.3 cm for 9 seconds at setting 2 (16 volts) and through a glass Wratten 18 A UV filter plus a 0.6 neutral density filter exposed. The exposed sample was ^{further treated at 22 °} C. for 40 seconds in a paper stabilizer device having four troughs. (Agfa-Gevaert-Fotorite, model DD 1437) · A standard 1-phenyl-3-pyrazolidone-hydroquinone developer of high pH was used in the first three troughs and solution A, which is composed as follows, in trough 4 :

Solution a

3 molar KBr solution 50 ml

3 molar aqueous Cu (NOOp ^ HpO solution 25 ml

3 molar aqueous citric acid solution 50 ml

1 molar aqueous Fe (NO,), 9 HpO solution 50 ml

1-cyanoguanidine (1 g / 100 ml H ₃ O) 50 ml

Triphenylguanidine (1g / 100 ml ethanol) 50 ml

Water: remainder to 1000 ml

pH value: 1.10.

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The treated sample was then placed on a copier machine such as an "A.B. Dick 320 Office Duplicator ", and using the dampening solution B were 25 good offset copies with black lithographic Printing ink produced.

Composition of the humidifying solution B:

Starting moistening solution as described in Example 2, pH: 3 »9 2ο ml

Gum arabic lg / 100 ml H ₂ O) 20 ml

Diet ethylene glycol mono-n-butyl ether 50 ml

Remainder: water to 1000 ml pH value: 3.90.

A sample of the same emulsion coating on the same backing paper, exposed and further treated in the same way, however, which had not been treated with benzotriazole solution, would not accept printing ink and also do not provide printed offset copies.

Example 15

An ortho-sensitized Gel.atine-Silberb.lorbromid emulsion with 70 mol .- ^ bromide and 30 mol .-% chloride, which contained 111 g of gelatin per mole of silver halide, with a layer weight of 88 mg / dm silver halide a layer support made of polyethylene terephthalate according to Example 1 is applied. The dried emulsion was covered with an abrasion protection layer made of gelatin, with a layer weight of 2.5 mg / dm gelatin hardened with 4.25 g dimethylolurea per 100 g gelatin. The photographic PiIm produced was exposed through a halftone and line test negative for 6 seconds with a 500 watt RSP-2 reflector point light lamp which had tungsten filaments and at 15 volts at a distance of

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127 om worked. The exposed photographic film vmrde Developed in the developer solution ^^ of Example 14 for 30 seconds with the exception that the developer contained 2 g / l benzotriazole; then 30 sec. at 20 ° in treated with an aqueous solution of the following composition:

3 molar aqueous copper (II) nitrate solution 5 ml

3 molar aqueous citric acid solution 10 ml

3 molar aqueous potassium bromide solution IO ml

Water - 75 ml

The activated film was rinsed with water for 5 seconds and placed in an offset office copier, with 2 wt .-; a Acetic acid as a dampening solution! © uses and with a lithographic printing ink good negative oleophilic lithographic Good quality images were obtained. But became a developer completely free of benzotriazole applied, no oleophilic lithographic image was obtained stop.

Example 16

A highly sensitive, ortho-sensitized gelatin silver oodbromide emulsion with a content of 1.2 mol% silver iodide and a gelatin: silver halide ratio of 0.36 μm with a layer weight of 7 »2 mg silver bromide per dm on a photographic Carrier film made of polyethylene terephthalate applied. The emulsion was covered with an abrasion protection layer which contained 10 mg / dm gelatin hardened with 2.96 g formaldehyde and 11.25 g dimethylolurea per 100 g gelatin. The material was overlaid by smear coating at 38 ⁰ C and 2.74 m / min, with a nickel (II) -hexacyanoferrat- (Il) sol by scraping, which was composed as follows:

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Lö surr; A.

Water 800 ml

Mckel (II) nitrate hexahydrate 0.75 S

Potassium citrate monohydrate 0.61 g

Solution b

Water 190 ml

Potassium hexacyanoferrate (II) trihydrate 1.06 g Sodium octylphenoxyethoxysulfonate 10 ml (4.2% aqueous solution)

Solution A was added to solution B with vigorous stirring. The sol coating was then dried with hot air.

The material was exposed through a step wedge and line image transparency for 10 seconds with the K&M light source according to Example 14 at a distance of 127 cm using an ultraviolet filter and a neutral density filter of 0.6 optical density. The exposed material was developed .: 20 sec. At 22 ⁰ C in a conventional hydroquinone / l-phenyl-3-pyrazolidone-Entwiekler, 0.25 g benzotriazole contained per liter, then 5 sec. Washed with water and then 30 sec . Treated at 22 ⁰ C in an aqueous bath with the following composition:

3 molar aqueous copper (II) nitrate solution 25 ml 3 molar aqueous potassium bromide solution 25 ml 3 molar citric acid solution 100 ml

Benzotriazole 0.25 g

Remainder: water to 1000 ml

pH value: 2.0

The plate was then rubbed with a 1% aqueous dispersion of colloidal SiO ₂ and used on an office copier for printing offset copies

1098T0 / U96

lithographic ink and a dampening solution below Composition was applied:

A concentrate of the moistening solution was prepared as follows:

3 molar aqueous orthophosphoric acid solution IO ml

0.5 molar aqueous solution of trisodium phosphate 25 ml

Remainder: water to 1000 ml

The moistening solution itself was then prepared from the above concentrate as follows:

Moisturizing solution concentrate 20 ml

Gum arabic solution (lg / 100 ml V / water) 20 ml

Diethylene glycol monobutyl ether 50 ml

Remainder: water to 1000 ml

Perfect lithographic images were obtained.

Example 17

A nickel (II) hexacyanoferrate (II) sol was made as follows
manufactured:

Solution a

0.1 molar aqueous potassium citrate solution 20 ml 0.1 molar aqueous nickel (II) nitrate solution 10 ml water I70 ml

Solution b

0.1 molar aqueous potassium hexacyanoferrate

(II) solution "30 ml

Partial sodium salt of N-lauryl-beta-iminodipropionate (lg / 100 ml alcohol) 4- ml

Water 166 ml

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Solution A became solution B within 15 seconds under strong Stir added.

A highly sensitive, ortho-sensitized gelatin-silver iodobromide emulsion with a content of 1.2 % silver iodide and containing 120 g of gelatin per mole of silver halide, with a layer weight of about 25 mg / dm on a smooth, polyethylene-coated, applied photographic carrier paper, which was coated with the sol by smear coating at a speed of 2.44 m / min, and dried with hot air.

Two samples were exposed through a step wedge and line image transparency for 10 seconds with a K&M 100 watt, 20 volt, incandescent lamp equipped with tungsten filament and operating as a point light source at setpoint 2 (16 volts) at a distance of 127 cm, with an ultraviolet -Filter and neutral density filter of 0.6 optical density was used. The exposed specimens were developed for 30 seconds at 22 ^° C. in a customary hydroquinone / 1-phenyl-3-pyrazolidone developer which contained 0.25 S benzotriazole per liter. A sample was activated for 8 seconds in the following activator solution:

16, 3 ml ml 15, 5 ml 100, 0 ml 0.79 S. 1000

aqueous copper (II) nitrate solution 3 molar aqueous potassium bromide solution 3 molar aqueous citric acid solution benzocbinone
Rest: water too

The second sample was activated for 8 seconds in the following activator solution:

3 molar copper (II) nitrate solution 25 ml

3 molar potassium bromide solution 2-5 ml

- 26 -

Il

1098 10 / U96

3 molar citric acid solution 100 ml

0.2 molar i-> mercury (II) chloride

solution 50 ml

Remainder: water to 1000 ml

Each activated sample was hot air dried and used on an office copier to make good offset prints using a lithographic printing ink and the dampening solution according to Example 16.

Example 18

Material A is a highly sensitive, ortho-sensitized gelatin-silver iodobromide emulsion, which was applied with a layer weight of 25 mg equivalent AgBr / dm to a polyethylene-coated, waterproof paper support equipped with a gelatin intermediate layer in a red safety light of low intensity . A gelatin abrasion protection layer which contained an iormaldehyde hardening agent was applied over the moist emulsion layer, setting a layer weight of 15 mg / dm, and both layers were dried. Material B consisted of material A which had been coated with a nickel (II) hexacyanoferrate (II) sol ^{by smear coating at 38 0 G and 2.74 m / min.} This sol was made as follows:

Solution a

Water 800 ml

Nickel (II) nitrate hexahydrate 0.75 g

Potassium citrate monohydrate 0.61 g

Solution b

Water 190 ml

Potassium hexacyanoferrate (II) trihydrate 1.06 g Sodium octylphenoxyethoxysulfonate 10 ml (4.2% aqueous solution)

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Solution A was added to solution B with vigorous stirring. The sol coating was then dried in hot air.

Material A was exposed as described in Example 14 and further treated again as described in Example 14 humidifies the thus treated material with the solution A * and in contact with material B then 30 sec. At 22 ⁰ C crimped. The materials were separated from one another and then Material B was placed on an office offset copier and 10 copies were made using the dampening solution B of Example 14 and a lithographic printing ink.

The procedure of this example was repeated with the exception that before exposure and further processing of material A in the above process, the two materials A and B with a 0.01 molar solution of potassium ferrocyanide 2 min. Have been moistened. The excess solution was drained off the materials and these on the Air dried. Up to 500 offset images were obtained during printing.

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Claims (16)

DR.-ING.VON KREISLER DR.-I NG. SCHÖNWALD DR.-ING. TH. MEYER DR. FUES DIPL-CHEM. ALEK VON KREISLER DIPL.-CHEM. CAROLA KELLER DR.-ING. KLÖPSCH KÖLN 1, DEICHMANNHAUS Z8 patent claims 1. /} Process for the production of lithographic images, in which a photographic material consisting of a support with an overlying layer of a dispersion of a light-sensitive silver halide in a macromolecular, organic protein colloid binder is exposed imagewise, the exposed layer to form a silver image with a developer developed for silver halide, the developed silver image treated with an aqueous solution containing a) a water-soluble, inorganic copper (II) ion in a at least 0.01, preferably 0.01 to 2.0 molar concentration supplying copper salt, b) a water-soluble, inorganic halide in a molar concentration of 0.01 to 5 »in particular 0.01 to 0.5, which provides a halogen ion to form a silver salt which does not in water is more soluble than silver chloride, to reduce copper (II) ions, the reduction is ended before the entire superficial silver image is oxidized, characterized in that an oleophilic Compound is present at least when the material is treated with the aqueous solution or after Formation of the copper (I) ions. 2.) Process according to claim 1, characterized in that the oleophilic-making compound is at least one heterocyclic Contains nitrogen atom. 3.) Method according to claim 1 and 2, characterized in that the copper salt is copper chloride. Il 109810 / U96 - s- 4.) Method according to claim 1 and 2, characterized in that the Kupfersalζ is copper bromide. · 5.) The method according to claim 1 to 4, characterized in that the aqueous solution as a further component c) citric acid at a concentration of 0.01 to 0.25 mol / liter. 6.) Method according to claim 1 to 5 »characterized in that that the oleophilizing compound is benzotriazole or potassium thiocyanate is. 7.) A method for producing images with the formation of a colloid copper (I) ion image, characterized in that that the picture with an oleophilic compound in Brings contact, which is capable of forming an insoluble salt or complex with copper (I) ions. 8.) Lithographic printing plate made of a layer support and a layer of a macromolecular protein colloid lying in the same plane, characterized in that the Colloid is able to form a complex with copper (I) ions or to form a salt and with an oleophilic compound to form an insoluble complex or an insoluble salt of copper (I) ions. 9.) Printing plate according to claim 8, characterized in that that it contains reduced silver. 10.) Printing plate according to claim 8 and 9 »characterized in that that the oleophilizing compound is benzotriazole. 11.) The method of claim 1 to 7 »using such aqueous solution as activator solution has a pH of 0.5 to 6.0, in particular from 1.0 to 109810 / U98 has and a) a water-soluble, inorganic copper (II) ion in an at least 0.01, preferably up to about 2.0 molar concentration yielding copper salt b) a water-soluble, inorganic halide in a molar concentration of 0.01 to 5 * preferably 0.01 to 0.5, which provides a halogen ion to form a silver salt, which in water is not more soluble than silver chloride, contains, characterized in that the activator solution contains at least one of the following substances: 1) An oleophilic compound in a concentration of 0.1 to 10 g or more per liter, 2) a mild oxidizing agent in such a concentration that the weight ratio of Copper (II) to the oxidizing agent between 1: 5 and 100: 1. 12.) Process according to Claims 1 to 7 and 11, characterized in that the oleophilic compound is used Benzotriazole used. 13.) Process according to claims 1 to ¹ J, 11 and 12, characterized in that an Fe (III) compound is used as a mild oxidizing agent. 14.) Process according to claims 1 to 7 > H to 1J>, characterized in that benzoquinone is used as a mild oxidizing agent. 15.) Process according to claims 1 to J, 11 to 15, 109810/1498 - 4 - characterized in that one uses mercury (Ix) chloride used as a mild oxidant. 16.) Process according to claims 1 to 7> 11 to 15, characterized _{ da. "; Potassium bromide is used as the inorganic halide. IT ·) Process according to claims 1 to 7 , 11 to 15, characterized in that one works in the presence of citric acid, which is present in a concentration of 0.01 to 0.25 mol / l of solution. 109810/1496