DE2241474A1 - PHOTOGRAPHIC PRINTING PLATE AND METHOD OF MAKING THE SAME - Google Patents

Description

Photographic printing plate and method of making the same The invention relates to metallic photographic printing plates and methods for Manufacture of the same.

Photographic printing plates with metal supports are known.

Such plates are often made of a photographic resin or Polymer image on a metallic carrier. These printing plates have the power to that the pictures wear out relatively easily due to abrasion. Hence one can Do not rely on these plates from conventional lithographic printing Printing presses receives more than about 100,000 prints; Usually the panels are Can only be used for a much smaller number of prints. Considering the enormous Costs of taking the press out of service to replace the printing plates emerged, the printers were therefore forced to use bimetallic, trimetallic or To use intaglio printing plate, the production of which is very expensive and time-consuming is. The production of bimetallic printing plates is carried out, for example, according to the following Procedure: (1) An imaging metal, such as copper, is placed on a non-imaging metal Carriers such as aluminum are electrodeposited.

(2) The plate is coated with a photopolymerizable substance and exposed through a negative, thereby exposing the exposed surface of the plate are polymerized.

(3) The unexposed parts willow are removed from the plate by "ashing, leaving a reserve image on the galvanized surface.

(4) The image metal is etched through by touching the plate with a Etchant, treated like an acid, and finally (5) the reserve of the image areas removed by treatment with a suitable solvent; see. "Offset Lithographic Platemaking" by Robert P. Reed, Graphic Arts Technical Poundation, 1967, p. 99. The manufacture of a printing plate by this method often takes up to an hour. In view of the critical nature of each of the Process stage, the worker often has to be a highly trained skilled worker are used, whereby very high for the production of each printing plate Costs arise. The invention is based on the object of long-term use To produce printing plates which, in their preferred embodiments, are capable of in a conventional lithographic printing press under normal working conditions produce more than 150,000 prints. There is also the task of to provide a printing process that is easy to automate, so that this also reduces the weight of the pressure plate.

The invention relates to improved and faster methods of assistance of photographic printing plates to which electrically conductive metal images are adhered, preferably electrically conductive, bound to a grained metallic carrier will. This plate is made by using an image recording medium which has a physically developable image, with image forming means (i.e. a developer) in the form of a solution of metal ions treated to form an adherent to produce a conductive metallic image bonded to the carrier and thus a printing plate that can be used for a large number of prints. Preferably this plate is made by making a photosensitive medium} consisting from a grained metallic door and a photosensitive layer that is able to produce a physically developed image during exposure, exposed and an electrically conductive metal image, which adheres to the metallic Carrier bound, created by treating the medium with a suitable developer treated in the form of a solution of metal ions. The grain of the metallic support is designed in such a way that it is capable of producing with what is described above metallic image to form a bond so that one obtains a plate that can be used as a Printing plate and preferably used as a long-term usable printing plate can. These printing plates result. when examining with the one described below optical scanning roughness meter (OSRM) a curve with a peak height A between about 0.25 and 0.90 with a peak position B between about 0.35 and 0.80 with a p6i value C between about 0.40 and 10. The image recording medium which can be used according to the invention consists from a photosensitive layer on a grained metallic carrier, as described herein, or from a physically developable one Image that is not adhesively bonded to the carrier. With a preferred one Process uses an imaging medium that is quick to process leave and a very thin layer of an ablative photosensitive layer has a roughened metallic carrier, and a physical developer, capable of producing an image adhered to the support. Dtis Process can be carried out due to its simplicity and quick implementation automate easily.

The term "fast processing" refers to handling of the imaging medium at room temperature with chemicals such as silver nitrate and a reducing agent for the same, for the purpose of producing an electrically conductive one Metal image, which is adhesively bonded to the carrier, for a period of time usually less than about 2 to 5 minutes. The whole process after exposure including developing, sealing and painting can be done by one machine in less than about o to 10 minutes.

To further explain the invention, reference is made to the drawings taken.

Fig. 1 to 15 show with the optical scanning Rauhigkeitsmes ser (OSRM) obtained curve diagrams for the identification of different metal plate surfaces.

16 schematically explains the OSRM device which, according to the invention used to mark the surface of various metal plates.

Once the attached metal image has formed, you can the developed medium can be further processed to produce a printing plate. As part of such treatment is it generally beneficial the difference between the oleophilic nature of the image areas and the hydrophilic To enlarge the nature of the non-image areas. This can e.g. with a silver picture can be carried out on an aluminum support by covering the plate with fabrics, like mercaptans, which adhere to the silver picture surfaces and the same more strongly oleophilic do for yourself. treated alone or in combination with phosphoric acid, which attaches to the non-image areas and makes them more hydrophilic. Besides that one can use a lithographic preparation, wel ches a polymer such as gum arabic oder'carboxymethyl cellulose, contains, apply to the hydrophilic nature to improve the non-image parts of the plate. Furthermore, the service life the plate and its oleophilic texture can be improved by removing the plate Coated with varnishes that selectively only apply to the image areas, but not to the non-image areas Surfaces, adhere. Other compounds to improve printing properties These-r Isetallplatten are described in the French additional patent specification 77 56, the xerd referred to here. A silver picture can be made stronger - oleophilic are made by strengthening it in a metal ion bath that creates a metal image, which is more oleophilic than the silver picture.

The photosensitive layer is preferably removed in one process step plate making; however, this can also occur in the course of other processing stages take place. Usually this operation is done by touching the plate with a solvent for the photosensitive layer, usually one Solvent for the binder of the photosensitive layer. Further the metal image of the printing plate can be reinforced with reinforcements, e.g. from reducible metal ions, such as silver, copper or tin ions, together with a reducing agent for the ions. This reinforcement takes place before or after removing the photosensitive layer.

As a photosensitive material de image recording medium according to of the invention one can use all those substances which are of the physical Development to a metal image are accessible, i.e. they are all physical Developable light-sensitive substances can be used. Sensitive substances of this kind are worried; they include those light-sensitive substances which develop after exposure through so-called physical development permit.

The physical development takes place with a solution of reducible Metal ions and a reducing agent for the same, which selectively pass through the exposure to activated areas deposits metal. In theory, the first is Stage of such a development the formation of a latent metal image, which then through the metal formed during the reduction of the abovementioned metal ions is reinforced. The latent image metal can be the same metal as the metal formed in this reduction, or an aiidercs; for example can the latent image is a silver image and the metal deposited by reduction is copper or be silver.

In silver halide photography, the latent silver image is formed in the silver halide grain in the emulsion, and the physical one is used Development to make the photographic image visible. They are useful Reducible metal ions for the silver halide film already in the light-sensitive Emulsion contained in Fos of silver halide. However, you can also kick it use an external source of reducible metal ions. Suitable photosensitive Substances are silver halides, such as silver chloride or bromide, azo compounds, e.g. inter alia the compounds described in British patent specification 1 064 72G, Photoconductors as described in U.S. Patent 3,380,823 and ferric compounds.

A physically developable image within the meaning of the present invention is an image which is applied in this way to a grained metallic carrier is that it is when treated with a physical developer that is a solution of metal ions, the deposition of a conductive metal image in al Bonding to the carrier is catalyzed, so that a plate is formed, which is used as a printing plate and can preferably be used as a long-term usable printing plate.

A physically developable image, i.e. an image made up of catalytic Germinating, (1) the image that forms upon exposure, e.g.

the latent silver image in silver halide emulsions or the reversible latent image on a reversibly activatable photoconductor, such as titanium dioxide, (2) it can be the irreversible image that results from the treatment of an exposed, a medium carrying an photoconductor with rope-sensitized metal ions, e.g. a solution of silver ions that forms, which lead to the formation of an invisible irreversible Image or a visible netal image; (3) it can show the latent iron (lI) ion image be sensitized by exposure to a ferric salt Medium forms, which subsequently with a silver ion solution for the purpose of Bild1mg a silver image is sensitized; or (4) it can be an electrically conductive one To be an image or a germinal image, produced by printing, by writing, according to the French U.S. Patent 7,033,106, by physically applying a metallic image on the carrier, by diffusion transfer of metal ions according to USA patent 3 300 306, with the aid of an imagewise exposed photopolymer layer over a Seed layer, for example according to US Pat. No. 3,615,446, has been generated is; or it can be the nucleation which by exposing a. pre-exposed light-sensitive material, such as lead iodide or As2S3, according to Malinowski: "Photographic Scionce and Engineering "Vol. 15, No. 3, May-June 1971, or (5) it can be the photographic silver image which is differentiated by conventional, ie. formed primarily chemical, development of a silver halide emulsion Has.

The physically developable image can be in close contact with the surface of the support or close to it, but at a small distance from the carrier, such as when the image recording medium consists of a roughened support, a photosensitive support having a physically developable image Layer and a water-permeable layer of a thickness of up to a few microns to the support and the light-sensitive layer.

Among the light-sensitive substances are photoconductors, especially those described below are particularly preferred.

The preferred imaging medium according to the invention is from a photographic plate in the form of a metallic support with a photosensitive Material,.

which is preferably located in a binder layer.

The most preferred image recording medium for the purposes of the invention consists of a photographic plate in the form of a grained metallic support with a light sensitive layer that is less than about 2 b thick and a Photoconductor, such as silver halide, or a photoconductor that acts upon exposure with activating radiation is reversibly activated and is able to produce a chemical Trigger reaction at the exposed areas, and the -ser photoconductor is preferred deposited on a superficially roughened trarrer and from the monthly Carrier isolated from the photoconductor. The photoconductor is preferably in particle form before, is preferably embedded in a binding agent that insulates against the photoconductor and is a very thin, removable layer on the support, especially a superficial one roughened carrier, deposited in such a way that the photoconductor is at least partially located in the roughened part of the carrier. This can be done easily by, for example, inserting a photoconductor, such as silver chloride, into one Solvent and binder existing solution of relatively low viscosity brings in and coated the roughened carrier with it. The coating compound can then be left to dry. Such a carrier with a coating of photoconductor and binder preferably has a very thin, solvent-permeable Coating and can be processed quickly in the preferred developers.

The granular metallic carrier must be able to bond with a metallic image produced as described above, so that a plate is created that can be used as a printing plate and preferably as a long-term Printing plate can be used and when examining with the optical surface roughness meter (OSRM) a curve with a summit height A between about 0.25 and 0; 90 with a summit location B gives between about 0.35 and 0.80 with a psi value C between about 0.40 and 1.0. Such grains can be obtained through physical graining, e.g. through brush graining, Spherical graining, graining with the sandblasting blower, or by chemical graining, e.g. by etching with acid or Alkali. The chemical Cores catm e.g. expediently by electrochemical treatment in an acid bath, such as hydrochloric acid, nitric acid or a mixture of nitric acid and acetic acid, take place.

According to a preferred Ausfilrungsform it was surprisingly found that it is possible to use a long-term metallic printing plate of similar: Establish lifetime as the bimetallic plates described above have (lifetimes in a conventional lithographic press below ordinary Conditions of more than 150,000 prints), with the difference that the plates according to the invention can be produced by a much simpler process. To the For the production of line recordings one can use plates in which the Körnwig the metallic, preferably aluminum, support during the examination with the OSRM device a curve with a peak height A between about 0.50 and 0.85 at a G pfellage 3 between about 0.60 and 0.75 with a psi-Xert C between about 0.65 and 0.9Q results. The curve has a peak height for the production of raster images A between about 0.75 and 0.85 with a peak position B between about 0.70 and 0.75 and a psi value C between about 0.75 and 0.90.

As a long-term usable plate "is provided with an image Pressure plate referred to in a working under normal conditions conventional high-speed offset lithographic printing press such as a Harris Cottrell M-1000 press manufactured by Colonial Press Inc., Clinton, Massachusetts V.St.A., which is a 62.9 cm x 92.7 cm measuring 4 units Perfecting heat set web offset press, at an operating speed of 26,000 prints per hour on white flat printing paper (22.7 kg) untor use of black printing ink (IPI), incompressible "Dayco" -aachen and an "Imperial" fountain solution capable of at least about 100,000 prints of good quality and preferably-at least about 150,000 Delivering prints without affecting the quality of the prints due to image wear and tear or erosion of the image from the printing plate suffers significantly. The ones in the following Plates used in the examples are such long-term usable printing plates. As the examples show, there can be a certain amount of wear and tear before the Attempt is finished; with many types of printing, e.g. when printing line art, this does not affect the value of the plate.

If a plate provided with an image is used as printing plates according to of the invention works, it produces it in a conventional lithographic offset press at least about 5000 prints under normal conditions. Typical for one Press is the Narr'is Aureiia press described in Examples 1 to 7 below. Example 1 is an example of a plate that has one of these or a better one Has performance since the trials of this example in an overloaded press were carried out.

To measure the grain size of the metallic used according to the invention An optical surface roughness meter (OSRM) is used for the carrier. The OSRM device is suitable for marking the surface topography of an opaque Sample as well as for the identification of other properties of transparent sample, at In the reflection mode, a laser is suitable for illuminating the surface a rotating sample. Reflected laser light is bundled at a pinhole, where its intensity is determined. This gives you valuable diagrams of the energy spectrum of the reflected coherent light as a function of the frequency that defines the surface topography mark the sample.

To identify the surface topography of a reflective Surface makes the OSRM device from a coherent light source, such as a laser, Use whose beam through a spatial filter (spatial filter), a collimator lens and directing a beam splitter onto the surface of the sample. The sample is mounted on a rotating support. Modulate surface irregularities the reflected coherent beam that is passed back through the beam splitter and is bundled by a Transforr: ierungsobJektiv on a pinhole, behind which is a photo tube. The pinhole is in the rear focal plane of reflected light. You get valuable diagrams of the energy spectrum of the reflected coherent light that characterize the surface topography of the sample.

As the OSRM device, the coherent energy spectra of diffracted light miest, another advantage is that there are known coherent relationships between Energy spectra and statistics of rough surfaces; see e.g. "The Scsttering of Electrornagnetic Weves from Rough Surfaces "by Peter Beckmann and Andre Spizzichino, Pergamon Press, London, 1963. A very important advantage lies in the. exact Classification of the surface topography, which is relatively easy with the here beocfiricbcnen Vorrictunen is available. For example, with the new devices easily the symmetry or directionality of the statistics of the surface topography determine. This was impossible or at least impossible with the devices known up to now very difficult.

A particularly important feature of the OSRM device is that it provides a direct representation of useful information. It is not necessary, to transform the obtained values in order to be able to make meaningful comparisons. According to a preferred mode of operation, diagrams can be obtained directly, the enable the operator to represent the energy spectrum of the surface, and such diagrams can be used to directly compare the various patterns with one another be used. this is particularly important for quality control, where the The focus is often on the ability to quickly examine the samples.

Fig. 16 is a schematic illustration of the OSRM examiner for the measurement of the coherent energy spectra of that reflected from the surfaces of Kietallplatten Light.

In this device, the laser 1 serves as a source of coherent Light. Suitable lasers are ilium ion, argon, krypton, etc.

The laser 1 can be replaced by other light sources that are useful and deliver independent results. However, there is only a limited area of conditions within which the results obtained with different light sources can be directly compared with each other, and within that the above specified analysis is valid.

These conditions are as follows: 1. The diameter of the light source must be smaller than the width of the scanning diaphragm; the size of the aperture is given by the desired bandwidth resolution of the spatial frequency. (The size of the light source determines the spatial coherence "of the light source.) 2. The (spectral) bandwidth ## of the maximum wavelength of the light source, which determines the time coherence of the light source, is given by the relationship given, in which the mean wavelength of the light source, the angular width of the scanning diaphragm and Omax mean the maximum angle of rotation of the sample.

Because the device described here uses the coherent energy spectrum measures of diffracted light, the whistled light must be at least partially coherent be. In general, the required degree of coherence depends on the particular Intended use. It is preferable to use light sources which have a moderately coherent Emit light. Light sources, such as lasers, which emit practically coherent light, are particularly preferred.

The laser beam is spread out through the spatial filter 2 and is optical Noise removed. The beam is directed in parallel by the collimator lens 3. A beam splitter 4 divides the beam into two parts, one of which is reflected and excreted will. The other part goes through the beam splitter 4 and falls on the Surface of sample 5, an opaque sample, its surface roughness should be determined. The sample 5 rulit on a turntable 6.

The table 6 is moved by the turntable motor 7 by one through the plane The axis running along the sample surface rotates.

The Laserstr.slll is deflected from the surface of the sample 5, and Some of the coherent light diffracted is by the beam splitter 4 thrown back through it.

Again, the reflected light is reflected in a part and divided a let through part. This time. However, the part of the radiation that falls through becomes excreted while the reflected part through a transform lens 8 falls and this part of the reflected light is bundled at the perforated diaphragm 9 will. Immediately behind the aperture 9.

there is an intensity detector, such as a photometer 10.

The pinhole 9 is located at the rear focal plane of the reflected Light. The photometer 10 is only reached by that light, which from the Surface of the sample 5 is scattered back antiparallel to the direction of illumination.

Since the sample 5 rotates, the angle #I which the illuminating beam forms with the direction perpendicular to the sample can vary between 0 ° and 960. The light reaching the photometer 10 is that component which has an angle of incidence of and is scattered by the surface of the sample 5 at an angle, where # I = the spatial frequency Xf of the component diffracted by an object when the incident field is perpendicular forms a WinIel #I to the object and the component is scattered at an angle #D with the perpendicular, by the equation given. In this case, the spatial frequency of the diffracted component is given by the equation given.

With the help of the device shown you can do the most diverse Obtain data, particularly in the form of charts.

In one embodiment, one of those detected by photometer 10 can be Intensity proportional electrical voltage signal used to generate the Registration pen on the x-y recorder 11 in the y-direction; to lead by mdfl the switch 12 closes and thereby connects the photometer to the y-spring drive 13. According to another embodiment, an emitted by the photometer 10 is electrical voltage signal multiplied by sin #. This is done by (iffnen of the switch 1 iuid Sclllieciol the switch 14 and 1.5. Of the Multiplier 18 then performs the desired multiplication of the signals from the photometer 10 and the sin 0 generator 19 through. The output from the multiplier 18 is transferred to the pen drive 13.

The x-axis of the x-y scroller 11 can be representative of sin Q or O be made. In the case of the former embodiment, the switch 16 closed, so that the sin generator 19 is connected to the lower drive 21.

In the latter case, the switch 16 is opened and the switch 22 closed, so that the G-generator 23 is connected to the s-peder drive 21.

One can work so that the y-axis of the x-y recorder 11 either the light intensity (I) or the product ate of the light intensity (f) and represents sin 0. In the same way, the axis of the x-y recorder 11 can either represent o or sin 8. Therefore, the x-y recorder 11 can immediately provide diagrams, the (I) as a function of O; (I) as a function of sin Q; (I) x sin 8 as a function of 8 or (I) x an O as a function of ton represent a Q.

If the x-axis of the recorder 11 corresponds to a Q, it is hers Scale of. The size of the scattered areas on the test surface is inversely proportional. A common expression for the reciprocal size of these scattering points is the spatial frequency.

Multiplying the intensity (I) by sin 8 is on the axis equivalent to integrating the scattered intensity of all azimuth angles for a given scattering angle for an isotropic surface. This has the effect that the range of high angular spread (the range of high spatial frequency) is preferred and the area of low spatial frequency is pushed back. When the intensity (I) is represented directly on the y-axis, the low spatial frequencies highlighted.

In all measurements, the photometer 10 is set so that the measured value of the reflection at normal incidence (#I = = o) - on the recorder full scale before the sin Q weighting factor is introduced. This normalization eliminates the influence of differences in reflectivity different test surfaces eliminated, so that a direct comparison or contrast between measurements of most rough surfaces becomes possible.

Since, as described above, an x-y recorder is used, the sample rotates at a linear speed.

However, if you put the linear drive mechanism through a drive which rotate the sample at a speed proportional to the arc sin o lets, 'the x-y recorder can similarly through a recorder be replaced with a drive based on time on the x-axis. In this way the arc-sin drive mechanism causes the x-axis to be proportional to sin Q.

The coherent energy spectrum of that reflected from the sample surface Light is shown in the rear focal plane of the traiisformierungsobj-ektivs 8. Since the sample 5 rotates, its energy spectrum is transmitted through the pinhole 9 through. This device therefore effects a test of the energy spectrum, i.e. the pinhole 9 scans a line drawn through the energy spectrum. -The exact OSRM method by which the diagrams are made showing the grit Describing the metal plates according to the invention is carried out as follows: A 1 milliwatt helium neqn laser is used as the light source. The spread of the beam and removal of the optical noise is done with the help of a Raunifilter spreader according to Gaertner. Provides a lens with a focal length of 2 inches a directed beam of 1 cm in diameter. The directed light beam passes through a cube-shaped, 2.54 cm beam splitter that splits the light into two parts: part is reflected and eliminated, and the other part goes through the Beamsplitter passes through it and illuminates the samples, which are aluminum plates whose surfaces have undergone various treatments. The light is deflected from the surface, and part of it falls back through the Beam splitter. The light reflected from the sample surface is used by the.1 beam splitter divided into two parts: the continuous part is eliminated, and the reflected part Part falls through a lens with a focal length of 5.08 cm, which this beam bundles at a pinhole. Only that light reaches the phototube which is scattered back antiparallel to the direction of illumination by the test plate. the Samples are mounted on a mechanism that rotates them around a through the plane of the Let the axis of the sample surface rotate, so that the angle X that the illuminating Ray with the direction perpendicular to the plate, varies between Oo and 900.

The rotation speed of the sample is adjusted so that the Making a curve (O to 850) takes 15 seconds. That coming back to the phototube Light is the component that comes from the surface at an angle Q to the vertical has been scattered, so considering the actual scattered component the combination of the angularly offset illumination beam and the scanning angle forms an angle of 2 Ω with the perpendicular direction. The output voltage of the Phototube goes through an amplifier and becomes one with the output voltage sine potentiometer connected to the plate rotator. The result is recorded on an x-y chart recorder in which the y-axis corresponds to the product from the light intensity (I) and sin (@), and the x-axis recorder is taken directly from the sinuo potentiometer tension driven. Therefore, the registration device bears the product (I) x sin (#) in .. dependency from sin (o) to.

As a result, the scale of the x-axis is inversely proportional to the Size of the scattering points on the sample surfaces.

The conventional expression for the reciprocal quantity is the spatial frequency. The multiplication of the y-axis by sin (0) is equivalent to the integration of the scattered Intensity of all azimuths for a given scattering angle. This has the Effect that the range of high angular dispersion (high spatial frequencies) is preferred while the low frequency range is pushed back. At all Measurements, the photometer is set so that the measured value of the reflection at normal incidence C8 = 0) a full scale deflection (10 units) on the registration sheet (before the sin (#) y-axis weighting factor was introduced will).

The scale of the x-axis is also set so that a deflection of 10 units of the optical cutoff frequency. (for ç = 900). this will called normalization and eliminates the influence of differences in reflectivity different samples so that a direct comparison between measurements this is made possible.

The OSRM device generates four curves to identify the grain size of the metallic carrier. The curves become easier with the help of the following four parameters marked: (a) the peak height A (vertical axis on a scale from zero to 1.0) the highest of the four directional curves generated on each surface, (b) the summit position B (horizontal axis on a scale from zero to 1.0) the highest of the four on each upper.

surface generated direction curves.

(c) the psi value C, which is a measure of the extent of fine structure is used in the user interface and is defined as follows: (1) the summit height A and the summit position B are determined, (2) the height of the OSRbI track for the highest of the four curves is at the 0.90 location on the horizontal axis and (3) the psi value C is the ratio of the value obtained in (2) to the summit height A; and (d) asymmetry; the asymmetrical nature is acceptable as the value of the difference between the height of the summit A and the height of the lowest Curve given at position B on the horizontal axis.

The thickness of the photosensitive layer or the image-forming layer Layer and the insulating or adhesive layer if one is present) on the type of photosensitive material, the type of binder, if any is present, the amount of activating radiation applied, and other similar Factors. But in order to obtain an image recording medium that can be processed quickly leaves, these layers should preferably be relatively thin and in particular have a thickness of less than about 2, preferably less than about 1. Furthermore, the thicknesses of the photosensitive layer and the iso-11 or adhesive layer vary. In the case of a metallic carrier, for example, the coating can with exception those parts that penetrate the roughened surface are scraped off. The thickness of the coating can vary depending on the desired effect. Particularly preferred However, a carrier with a coating of less than 1 µ thickness is used to at faster Processing to obtain coherent metal images that adhere to the carrier are bound.

The ratio of the amount of binder to the amount of photoconductor or the other light-sensitive material can vary within wide limits; preferably amount to Weight ratios of light sensitive Material to binder 1: 6 to 6: 1 and especially 1: 1 to 1: 3 ..

In the embodiment in which a photoconductor is in the roughened If the surface of a metallic support penetrates, the photoconductor is said to be from the metal insulated from the wearer. This isolation can be done by the binding agent, by distributing the photoconductor, but it can also be covered by a separate insulating layer, like a silicate layer, or by one on the metallic support Metal oxide layer, or the photoconductor itself can be used as an insulating layer work when this layer is thick enough.

The insulating layer serves to protect the photoconductor or the other light-sensitive Material against the photoconductor to: isolate. A photoconductive isolator is a that which is the transition of the generated by exposure to activating radiation Electrons from the activated light-sensitive material, e.g. a photoconductor, to the electrically conductive metallic carrier prevented. This insulating layer is preferably a solvent permeable layer of at least 14 i Thickness. A preferred printing surface of good wear resistance is a Aluminum carrier with an oxide barrier layer from 100 to 200 i thick.

This layer is used for printing plates that can be used for a long time in animals preferably produced by anodic oxidation.

According to the invention, silver halides are used as the Itoto conductor or photocatalyst and reversibly activatable photoconductors before given to the activating upon exposure Radiation remain essentially chemically unchanged. A preferred group of such Photosensitive substances are the inorganic substances, such as compounds of a Metal with a.

Nonmetal from Group VIA of the Periodic Table, such as Oxides, e.g. zinc oxide, TiO2, zirconium dioxide, germanium dioxide, indium trioxide, metal sulfides, such as cadmium sulfide (CdS), zinc sulfide (ZnS) and tin disulfide (SnS2), metal selenides, such as cadmium selenide CCdSe). Metal oxides are particularly popular as photoconductors in this group preferred. A particularly preferred metal oxide is TiO2 because it is a surprising one has good photosensitivity. TiO2 with an average particle size of less than about 250 my, that in an oxidizing atmosphere at temperatures above about 2000 C has been treated is particularly preferred, and especially is a TiO2 is preferred, which is produced by high-temperature pyrolysis of titanium halide has been.

The silver halide preferably used in the context of the invention is dispersed in a binder and contains an excess of halogen ions over the silver ions. The silver halide can be silver chloride, silver bromide, silver iodide or a mixture of these halides. The grain size of the silver halide becomes regulated so as to obtain the desired photographic sensitivity. It can be advantageous, sensitizing dyes, Gainma regulators, such as phenyl mercuryl acetate, and physical developer sensitizers such as sulfur compounds e.g. tetramethylthiuraindisulfide, to add. The developer sensitizer improves the nature of the metal deposit, which occurs during the physical development of the exposed silver halide plate forms.

A physically developable image can also be created by applying Germs are generated on the metallic carrier.

This can be done by placing the metallic support, e.g.

with a graphite pencil, labeled, or you can use a keisuschic} ft preferably apply in a binder on the carrier and with a photoconductive cover the feasible layer and then expose the layer to the exposed Position to make impermeable. Germs can consist of any substance that can cause the Deposition of metal from the physical developer is catalyzed. There are many such substances are known as metal sulfides, fine metal particles, graphite and like that.

According to the invention, certain fluorescent photoconductors can be used as photoconductors Substances are used. Such substances include, for example, bonds, such as those with silver activated zinc sulfide and zinc oxide activated with zinc.

To shorten the description, reference is made to the Belgian patent specification 736 126 reference, in which the methods are described in detail, .the according to the invention can be used to produce photosensitive plates, to expose, to physically develop and further process into printing plates; further is in the cited patent also the use of the printing plates in printing processes described.

The printing plates preferred according to the invention generally require a minimum amount of metal in the image areas in order to obtain acceptable printed images. In general, at least about 1.0 g of metal per m is required in the image areas, around Irucklebenslebenzi; of at least 5000 prints in a standard lithographic To achieve press. To produce a long-sided usable printing plate according to According to the above definition, the image areas should preferably be at least 3.0 and in particular Contains 8.0 to 12.0 g of metal per mg.

However, the amount of metal in the picture areas depends on the one a certain period of use is required, depending on the type of material produced in the image areas Metal. Furthermore, the above figures are based on the assumption that one can find a suitable Grit used to have the necessary adhesiveness between the metal of the picture and the Achieve carrier. It is also believed that various catalysts, such as Sulfur compounds, the activity of the developer and other changes in the Reaction conditions the type and amount of the developer, e.g. a physical one Developer, in the form of a solution of metal ions and a reduction agent for affect the metal ions, deposited metal. The amount of metal per unit area For acceptable images is based on the assumption that the image itself is predominant Part, d, hi to more than 50 °, consists of metal. The> metal content is preferably in the image areas 90 to 100, in particular 95 to 100 percent by weight of the amount of the image material in the image areas. The rest of the material in the picture areas generally consists of an organic binder and various reaction products of the photographic development process. In these proportions, however, the after-treatments that are carried out after the creation of the metallic image Preparing the plate for printing is not considered.

A preferred physical developer in the present invention is a it stabilizes physical developer, consisting of a solution of metal ions, a reducing agent and an ionic surfactant as developer stabilizer; a A particularly preferred stabilized developer contains a soluble silver compound, an iron (III) compound, an iron (II) compound and an ionic surfactant, as described in British Patent 1,063,694, incorporated herein by reference is taken. This patent describes the use of an acid reactive physical developer, which has a soluble silver compound and consists of, In addition, an iron (II) compound, an iron (III) compound and an ionic surfactant contains as a developer stabilizer, the concentration of the silver compound more than 0.006 Mol / l, that of the ferrous compound more than 0.05 mol / l and the ferric compound in such a concentration it is the development speed and / or the life of the developer are greater than the development speed and / or lifespan of a reference developer of the following composition: iron (II) sulfate 0.050 mol / l iron (III) nitrate 0.005 Mol / l citric acid 0.14 mol / l silver nitrate 0.006 mol / l, which is the same stabilizer in the same amount, the development speed and the life In each case at least correspond to those of the reference developer.

The present description explains a negative in general (i.e. from negative to positive or vice versa) working process; the procedure However, it is equally applicable to positive working processes such as those in US patent applications Serial Nos. 38 029 and 38 221 of May 18, 1970 and U.S. Patent 3,414 410 are described.

The metal image according to the invention is in contrast to the particulate one black or dark metal of most photographic images from a shiny, contiguous metal covering. Furthermore, these images are firmly adhered to the support. The nature of the image metal and the bond to the support give the panel the ability to as a printing plate and especially as a long-term usable printing plate to be used. It has been shown that silver images in view of their oleophilic nature and their long shelf life for the production of long-term Usable printing plates are preferable.

The use of metal plates of the specified grain allows the easy production of long-term usable printing plates with easy reproducibility of metal images of remarkable durability. The ones with the ones known so far The results obtained on plates, even if they are grained, show that the image fastness and / or the number of prints available can vary considerably, and these Difficulties are overcome by the new printing plates according to the invention. The reliability of the new panels according to the invention, which is primarily based on which is due to the remarkable image stability, and which is proportionate simple method of making and using these plates for long term printing represent a significant technical advance of the invention in printing plate technology represent by making the arduous methods of making printing plates nacji etching process obsolete and the unreliability of similarly manufactured panels of the stand of technology.

For similar carriers of a known type, the results can be seen do not always predict, and many plates fail on long-term printing. The metal carrier had to be grained (e.g. grained with the brush), provided with a picture, to be developed into the printing plate and then examined to ensure that the image remains stable while it is now possible to determine only those lletallplattei> to be selected with the same grain size that has been used for a long time Provide required image stability for printing operations.

According to a further feature of the invention, such printing plates preferred in which the metal image has a minimum weight per surface area. So it is not just the image stability by choosing plates with certain Grain guaranteed, but it will also ensure the long-term usability of the Plates ensured by the amount of metal in the picture areas, is controlled as described here.

As a result, the invention eliminates the uncertainty inherent in the previously known printing plates was characteristic, kept to a minimum, if not completely eliminated.

EXAMPLE 1 e 1 to 7 This group of examples shows that the imaging and printing properties of the plate made in accordance with the invention largely depend on the nature of the granular metallic support.

A series of grained aluminum supports of varying degrees of roughness is manufactured as follows: aluminum (type 110Q) with a thickness of 0.305 mm is granulated with a brush using a standardized puller granulation system. The Fuller system consists of two cores, each 30.5 cm in diameter, on which Polyamide brushes are arranged in a spiral. These brushes are made with a frequency about one oscillation every 3 seconds.

The aluminum foil comes from a roll at one speed deducted from 2.13 m / min. The pumice stone consists of silicon dioxide (grain size 350 Meshes). Under these conditions one obtains a grain that is identical to the investigation supplies the Kvrven shown in Fig. 1 with the OSRM device. Granulated this way Aluminum undergoes a series of etching treatments of progressively increasing length of time subjected to constant temperature and concentration of the etchant and then cleaned and anodized. The etchant contains 100 g NaOH and 5 ml "Pennsalt AX-11" (a complexing agent) per liter of solution and is kept at 500 ° C. rehearse of the aluminum grained with the brush become 10, 20, 40 ,. 50 or GO seconds immersed in the etching solution. The etched OFS-9292 samples will be Rinsed for 15 to 20 seconds in tap water at 35 ° C, 30 seconds in 5Q volume percent Purified nitric acid at 220 C, then 1 minute in tap water of 350 a and finally rinsed in distilled water for 15 seconds. All samples are 5 minutes in 10 volume percent sulfuric acid at 23 to 260 C and a current density of 2.69 Ä / dm2 anodized, then 1 minute in tap water at 350 c and finally Rinsed in distilled water for 15 seconds and air-dried. rehearse These differently etched plates are made with the OSRM device described above examined. After 2 days, the plates with the roller application machine with a Emulsion of silver chloride, which has an excess of chlorine ions, in Polyvinyl alcohol, phenyl mercuric acetate as a yarn improver and tetramethylthiuranide disulfide contains as a developer sensitizer, in a basis weight of 3 y Ag / cm2 plate surface coated. The weight ratio of silver chloride to binder is 1: 3. The emulsion solution has a total solids content of 4.5 percent by weight. the coated panels are air-dried, then through a standardized test negative and a 1.0 neutral density filter exposed to a carbon arc for 90 to 110 seconds, to get a continuous 4- to 5-step exposure.

The trial negative contains a standardized 21-step exposure wedge, two halftone screen test arrangements, a large solid block, a 50% screen, Slur targets and dot gain scales. Each of 12.7 cm x 57 cm measuring plates is then 2 1/2 minutes at 230 ° C in 620 ml of a stabilized treated physical developer solution containing 0.157 molar of ferroammonium sulfate hexahydrate, 0.063 molar in ferric nitrate nonahydrate, 0.299 molar in citric acid monchydrate and 0.115 molar of silver nitrate and 12.6 g of triethanolamine as a complexing agent Per liter, 0.094 g of "SC-134" per liter and 0.128 g of "Alamine-4", an ionogenic one Surfactant, as a development stabilizer, acetic acid and "Synthrapol-N", a non-ionic surfactant, per liter contains. The plates with pictures are then rubbed with a varnish made from a solution of 5 g of mercaptobenzothiazole in 20 m dimethylformamide with an addition of 50 g of 85 percent phosphoric acid to 1 1 from J. Stark'schem rub-in developer, a plate varnish made from gum arabic and phosphoric acid and an oleophilic resin. The six different Etched plates are then placed side by side on the plate cylinder of a lithographic 66 cm Harris Aurelia 126 offset sheet-fed press with conventional dampening system upset. The non-compressible rubber blanket (Dayco) is then given a 0.13 mm thick polyester film backed to the condition of an overload of 0.13 mm thickness between the plate and the rubber blanket and thus the wear to accelerate the plate. A conventional lithographic ink is used ("GPI Black Offset 60-N-165"). The wet solution contains 7.5 g of gum arabic from 14O trees and 1.5 g "Imperial concentrate" per liter of water. Used as paper conventional wood pulp paper for plaque printing with a smooth surface (22.7 kg), and the press is running at a speed of 8000 prints per hour operated.

The wear of the plates during operation of the press is monitored, by viewing the prints made. One tries to do both evaluate the local wear as well as the total wear by the line and halftone image scaling examined. The following failure points are recorded for each of the test panels: 1. If on the lower shade test card in the 3% -150 line grid (marked with "1 / 2A" on the trial card) at least 50 fo the point fe} ilen; 2. if on the upper test map in the 5% -150 line grid (5) at least 25 t% of the points fc {iln; 3. if in the big, 50% halftone screens the first visible signs of wear and tear appear; 4. if any visible wear, such as sand holes, in various contiguous Surfaces occurs; 5. if the overall wear and tear is judged to be excessively high, i.e. if there are obvious macroscopic signs of wear and tear without enlargement are visible.

In Table I are the wear failure points as a function of the Etching conditions indicated; The table also lists the service life values, at which these points are achieved in each case. It should be noted that this Plates were examined in an overloaded press, causing wear of the plates is accelerated by a factor of at least 2. Furthermore, these are Numbers by a factor of at least 5 greater than the results you get with obtained under the same conditions examined polymer plates.

The roughness distribution on the grained plates is generally viewed as the sum of several types of roughness, namely as a coarse grain, on which a finer structure is superimposed. P. Beckinann ("Scattering by Composite Rough Surfaces, Proc. IEEE, Volume 53, Pages 1012-1015) has shown that of radii Surface-scattered light at least as much from the fine structure as from the The coarse structure depends, since the finer structure has a larger mean slope (Ratio of the mean depth to the mean width of the grain) is listed as that Coarse structure, even if the depth of the coarse structure is greater.

Therefore, when analyzing the results of these examples, one must use the Take into account the type of changes the surfaces will undergo. The etch should the fine structure much tighter reduce or even eliminate, but only gradually change the coarse structure. This is due to the rehearsals OSRM curves obtained, which are shown in FIGS. 1 to 7, can be observed. the Curves have been described above.

The strength and abrasion resistance of the on different surfaces developed images are confirmed by relatively simple tests, such as the adhesive tape adhesion test, the dry eraser test and the wet eraser test, as well as through direct experiments in the printing press.

Images that fail the tape and erase tests behave in the printing press is unsatisfactory, although not always the opposite the case is. The tape test uses a strip of tape with firm finger pressure pressed against part of the connected picture on a plate so that the End of the adhesive strip is facing up. Then the strip is quickly peeled off. Poorly adhering images stick to the tape, while images that adhere well Images have very little or no silver transferred to the tape. The dry erase test consists of drawing the picture (about twenty times) with an ink-eraser gun rubs using the pressure required of a pencil eraser. Images of poor abrasion resistance are abraded in this way.

A stricter test is that you can do the same test with with a moistened eraser. An adherent image resists that Eraser tests, and the etching merely buffes the silver to a shine. However, the most objective test of the durability of the image is to try in the printing press.

In all of the above examples is the image obtained on development a coherent, electrically conductive metal image.

in contrast to the normally electrically non-conductive, particulate Metal image that is used during photographic development obtain will. The cohesive metal picture consists of large, adjoining one another Particle of metal and has the appearance of a continuous layer.

The picture is characteristically glossy; for example they are Silver pictures shiny, and this is the preferred form of metal for the intended Uses, i.e. for printing plates and electrical circuits, in contrast to the fine, particulate, black, non-conductive metal deposits, which are characteristic of most metal photographic images, e.g. black metal ash silver deposits in silver halide photography, which are generally electrically non-conductive.

When used to manufacture printed electrical circuits can the image recording media according to the invention after development and preferably after removing the photosensitive layer as such or after such a treatment of the metallic carrier that one can use the electrical circuit by removing the metallic circuit from the metallic carrier receives. any reagent that attacks the carrier, the metal image is indifferent to it, however, can be used to separate the metallic circuit be used. For silver or copper pictures on an aluminum carrier you can e.g. alkali, such as dilute caustic soda, or acids, such as dilute sulfuric acid, use. Further reagents for this purpose are known to the person skilled in the art. Possibly you can first embed the metallic circuit in a suitable carrier, before removing it from the aluminum carrier, and the circuit is then in the carrier in which it is embedded, as described above, from the aluminum carrier removed. t T a b e l l e I Plate failure points (as the number of Prints) Example 1 2 3 4 5 6 Etching time, sec 10 20 30 40 50 60 3% -150 raster (25% of points are missing) 220,000 16,000 8,000 5,000 3,500 <300 5% -150 grid (25% the points are missing)> 275 000> 275 000> 155 000> 68 000 5 000 <300 Lower 50% of the grid (microscopic defects) 207 000 120 000 47 000 8 000 10 000 2 000 Upper 50% of the grid (microscopic defects)> 275 000> 275 000 67 000 19 500 10 000 3 500 Lower contiguous area (visible wear) > 275 000 95 000 51 000 1 000 3 500 3 500 Cere contiguous area (more visible Wear)> 275 000 85 000 47 000 1 000 5 000 5 000 General wear (macroscopic Total error)> 275 000 110 000 60 000 14 000 10 000 5 000 T a b e l l e II OSRM sampling values psi value C at-peak-peak (see Asym evaluation game Fig. Type of plate height A position B text) metry results 1 2 10 sec alkaline 0.74 0.71 0.77 0.12 Very good pressure etching results (see table I) 2 3 20 sec alkali 0.56 0.61 0.68 0.06 Good (see table etching le I) 3 4 30 sec alkali 0.52 0.60 0.64 0.04 Sufficient pressure etching results (see Table I) 4 5 40 sec alkali 0.45 0.52 0.51 0.09 Poor pressure etching results (see Table I) 5 6 50 sec alkali 0.45 0.52 0.47 0.06 Poor pressure etching results (see Table I) 6 7 60 sec Alkali 0.37 0.44 0.43 0.10 Very poor etching printing results (see table I) 7 1 No etching 0.77 0.76 0.88 0.08 Due to the deeper Grain size better than with 10 sec etching; sometimes limited by purity (the Etching cleans the carrier).

i e i s p i e 1 e 8 to 15 Tests are carried out with aluminum supports undertaken various types of grain; around the corresponding to the different grain sizes Determine print quality and useful life. The aluminum support comes with coated with a photographic emulsion containing a 2 percent excess of chlorine ions, based on the total weight of the silver chloride contained in the emulsion. The emulsion also contains phenyl mercuric acetate as a gamma regulator and tetramethylthiuram disulfide as a developer sensitizer. The dried emulsion has a thickness of 0.3μ on the aluminum support. The plate is then covered by a negative for 30 seconds exposed to ultraviolet rays. The exposed plate is 2 to 3 minutes or until a shiny, coherent silver image has formed with treated with a stabilized, physical silver developer.

The developer solution is made by mixing 125 g of solution I, 25 g of solution II and, 6 g of 3 molar silver nitrate solution and diluting with distilled water manufactured on 1 1. The solutions I and II have the following compositions: Solution I Ferroammkoniumsulfat 78.4 g Solution I is distilled with 72.3 g ferric nitrate Ferrbiitrate 72.3 g water made up to 1 l citric acid 80.0 g.

Solution II Distilled water 100.0 g "Synthrapol N" 1.0 g "Armac 1 2D "1.0 g.

The plate is washed and coated with a printing plate varnish, the one made from gum arabic, phosphoric acid, mercaptobenz-othiazole, - dimethylformamide and an oleophilic resin, which - selectively only on the shiny silver image, but does not adhere to the plate background. The plate is connected in'die introduced with the printing press described in Example 1 to 7 and in a similar manner, as in example 1 to 7, using the OSRM device examined.

Example 8 uses aluminum foil (type 1100) with a thickness of 0.305 mm cleaned and without any roughening treatment according to the method of Examples 1 to 7 anodized in a sulfuric acid bath. Example 9 becomes the same Type of aluminum foil made by an electrochemical method in a nitric acid bath treated, which etches and anodizes the aluminum foil at the same time. .In example 10, an aluminum plate 0.305 mm thick is electrochemically grained in hydrochloric acid and then anodized in sulfuric acid according to Examples 1 to 7. In example 11, grained the aluminum plate in the same manner as in Example 10, but below Formation of a thick oxide layer anodized. Example 12 uses an aluminum support of the kind used in Examples 1 to 7 to produce a grain which gives the OSRM curves shown in Fig. 1, purified with phosphoric acid. This treatment increases the grain depth (probably as a result of the removal from dirt and grease) In example 13, an aluminum plate of the type 1100 is used with 0.305 mm thick electrochemically in a nitric acid solution. In Example 14 is an aluminum plate of the same type, by attaching it to a mechanically shaken flat bed table is pressed. The actual grain occurs through the interaction of Stalilkugeln and pumice stone. The process takes time about 20 to 30 minutes. In Example 15, an aluminum plate (type 1100) is electrochemical granulated in a nitric acid-acetic acid bath and anodized according to example 1 to 7.

The results of Examples 8 to 15 are summarized in lamelle III: T a b e l l e III OSRM samples summit-summit example Fig. Type of plate height A position B psi value C asymmetry 8 8 anodized, ungrained plate 0.07 0.10 0.14 0.06 9 9 Electrochemically grained and anodized 0.26 0.36 0.39 0.26 10 10 Electrochemical grained and anodized 0.52 0.60 0.69 0.02 11 11 Electrochemically grained and anodized 0.59 0.63 0.73 0.03 12 12 Cleaned with acid and grained with a brush 0.83 0.73 0.83 0.11 13 13 Electrochemically grained 0.81 0.66 0.77 0.02 14 14 spherical grain Plate 0.88 0.80 0.97 0.02 15 15 Electrochemically grained and anodized 0.93 0.73 0.88 0.03 - Table III continued on page 38 - Tabel III (continued) OSMR samples Example Evaluation results 8 Does not print; Image falls off when moistened.

9 Very poor print results; only a few hundreds of prints; worse than the plate of example 6 etched for 60 sec.

10 poor to mediocre print results; according to the between 40 and 50 sec etched plates of Examples 4 and 5.

11 Massive to good print results; according to the between 20 and plates of Examples 2 and 3 etched for 30 sec.

12 Acid cleaning has improved the grain; the printing results are excellent, even better than that of the plate of the example etched for 10 seconds 1.

13 Very deep grain gives excellent printing results similar to that Example 1 with regard to service life and quality.

14 This grain provides excellent image adhesion; However, it is unsuitable because the points of the grain penetrate through the image, thereby affecting the printing results and sand holes or other defects in the produce finished print.

15 Very deep grain, the excellent printing results X L L '<jI fitrt those of example 1, in terms of service life and quality ranett.

B e i s q i e 1 16 For a silver chloride emulsion ready for coating Cd, C12 # 2H2O is added in such a manner and amount that the emulsion layer contains 1.43 g silver and 0.51 g cadmium per m2 after application. The emulsion is applied to a paper carrier coated with baryta. The one made in this way Recording medium is then exposed imagewise.

The exposed recording medium and an aluminum foil of the in Example 15 specified composition and surface properties, their granular Surface yields the OSRf-1 curves shown in FIG. 15 are given by a conventional apparatus for performing the diffusion transfer process passed therethrough. This device contains an aqueous developer solution of the following composition: Sodium hydroxide 11 g sodium sulphite 100 g sodium thiosulphate 6 g potassium bromide 1.5 g hydroquinone 9 g 1-phenyl-3-pyrazolidone 1.5 g trinate: lithium salt of ethylenediaminetetraacetic acid 4 g of 3 illit of water made up to 1000 cm after passing through this solution the negative and the aluminum plate are pressed together between rubber rollers.

The sheet of paper supporting the emulsion layer is made up of the aluminum foil separated, with the silver image remaining on the aluminum foil and firmly attached to the surface Adhesive to the film, the plate thus provided with an image is now 2 to 3 minutes or so long 'until a shiny, coherent silver image has formed, which contains 8.0 to 12.0 g of silver per m2, with a stabilized physical Treated silver developer of the composition given in Examples 8 to 15, being a long-term usable Printing plate is created. This printing plate is then coated with a printing plate varnish of the composition given in Examples 8 to 15 coated and used in a high speed lithographic sheetfed offset press, to make more than 150,000 prints.

13 e i s p i e 1 e 17 to 27 The following examples show one possibility the change in the amount of metal in the finished picture areas.

A silver halide emulsion as used in Examples t to 7 serves as a control and is placed on a grained, anodized aluminum support applied with a thickness of 0.305 mm, the grain size of which has the following OSRM values corresponds to: summit height A 0.93 summit position B 0.73 psi value C 0.88 asymmetry 0.03.

Different sulfur compounds form the same emulsion added. The initial coating weights are in between in all cases D and 4.5 X 10-2 2 g AgAn2. The light-sensitive plates produced in this way are Exposed for 30 seconds with a "NuArc" charcoal arc and then for 3 minutes with a physical developer treated. The physical developer has the following Composition: Solution 1 Fe (NH4) 2 (SO4) 2 # 6H2O 78.4 g # Fe (NO3) 3 # 9H2O 32.3 g # made up Citric acid # H2O 80.0 g # on 1 # 1 solution 2 Ionic surfactant 0.8 g ("Alamine 4") Acetic acid 0.8 g non-ionic surfactant ("Synthrapol N") 0.8 g Mixed Developer: 125 ml solution 1, 25 ml solution 2, 6 ml 3 normal silver nitrate solution.

The amount of silver in the contiguous image area is determined by atomic absorption certainly. The results presented in Table IV clearly show that the additive of the sulfur compounds, the amount of deposited in the fully developed images Silver significantly increased. When the plates are rubbed with a lithographic varnish and are used in a lithographic offset press, provide those plates where the picture contains more than 3.0 g of silver per m2, thousands of excellent Print good image density and a clear background while the control sample, which only contains 0.14 g silver per m2 in the images, no prints of high quality grad supplies, has a significantly shorter lifespan and poor, unacceptable Copies results.

T a b e l l e IV Example Added sulfur compound Developed, Ag (g / m2) 17 No sulfur compound added 0.14 18 Thiuram 5.1 19 + 0.05 g Cysteine. HCl per 1 emulsion 4.7 20 + 0.10 g cysteine.IICl per liter 6.8 21 0.1 g 2-mercaptomethylimidazole per liter 7.3 22 + 0.1 g 4-thiazolidine carboxylic acid per liter 6.0 23 +1 ml mercaptoacetic acid (Thioglycolic acid) per liter 5.2 24 + 0.003 'g sodium thiosulphate per liter 6.2 25 + 0.1 g 6-amino-2-mercaptobenzothiazole per liter 5.1 26 + 0.05 g 6-amino-2-mercaptobenzothiazole per liter 6.5 27 + 0.1 g 2-mercaptobenzothiazole per liter 5.9.

Claims (29)

Claims )) Process for the production of a metallic one having an image Plate, in particular for use as a printing plate, characterized in that an image recording medium which has a physically developable image on it having a grained metallic carrier, with a solution of metal ions containing developer treated until an electrically conductive metallic Has formed an image adhesively bonded to the image recording medium, wherein the grain size of the metallic substrate is such that it is capable of to form a bond with the metallic image created as described above, so that a plate that can be used as a printing plate is created during the investigation With the OSRi device, a curve with a peak height A between about 0.25 and 0.90 with a peak position P between about OJ35 and Q.80 and with a psi value C between gives about 0.40 and 1.0. 2. The method according to claim 1, characterized in that the grain of the metallic carrier in the examination with the OSRM device with a curve a summit height A between about 0.50 and 0.85 with a summit position B between about 0.60 and 0.75 and with a psi value C between ebva 0.65 and 0.90. 3. The method according to claim 1, characterized in that the grain of the metallic carrier during the examination mlt the OSRM device a curve with a peak height A between about 0.75 and 0.85 at a peak B between about 0.70 and 0.75 and with a psi value C between about 0.75 and 0.90 results. 4. The method according to claim 1 to 3, characterized in that the image recording medium has a photosensitive layer which, in the Exposure creates a physically developable image. 5. The method according to claim 1 to 4, - characterized in that. the photosensitive layer has a thickness of less than about 2μ and also contains a solvent permeable binder. 6. The method according to claim 7 to 5, characterized in that one an aluminum beam is used as the carrier. 7. The method according to claim 6, characterized in that as Carrier uses an anodized aluminum carrier. 8. The method according to claim 1 to 5> characterized in that An aluminum carrier is used as the carrier, which is essentially non-porous Alumina layer at least about 14 Å thick on its surface having. 9. The method according to claim 1 to 8, characterized in that a solution is used as the metal ion solution that contains silver, copper, nickel and / or contains tin ions. 10. The method according to claim 9, characterized in that one Metal ion solution used, which is also a. Reducing agent to selectively reduce the metal ions in the Contains image areas of the medium. 11. The method according to claim 1 to 10, characterized in that the photosensitive material is removable from the support, and that after the formation of the metal image, the photosensitive layer of the image recording medium removed. 12. The method according to claim 11, characterized in that one uses photosensitive layer which is removable by solvent, and this photosensitive layer is removed with the aid of a solvent. 13. The method according to claim 1 to 12, characterized in that titanium dioxide or silver halide is used as the photosensitive material. 14. The method according to claim 1 to 12, characterized in that one uses a photosensitive material which is a photosensitive material Contains metal oxide or silver halide in a binder. 15. The method according to claim 13 or 14, characterized in that the silver halide used is silver chloride, preferably with an excess of chlorine ions, used. 16. The method according to claim 1 to 15, characterized in that the grained carrier by brush graining, ball graining, processing with the Sandblasting blower of chemical grain and subsequent anodic oxidation manufactures. 17. The method according to claim 1 to 16, characterized in that one carries out the development by treatment with a developing solution which Silver ions and a photographic reducing agent for reducing silver ions to a silver picture contains. 18. The method according to claim 1 to 16, characterized in that. that development is carried out by treating with a solution, which uses an ionic surfactant as a developer stabilizer, a soluble silver compound, contains an iron (III) compound and an iron (II) compound. 19. The method according to claim 1 to 18, characterized in that the image metal in the image areas at a density of at least about 1 g / m2 separates. 20. The method according to claim 1 to 18, characterized in that the image metal in the image areas at a density of at least about 3 g / m2 separates. 21. The method according to claim 1 to 20, characterized in that the medium is colored with a printing ink that selectively applies to the image areas or adheres to the image-free areas, and the colored medium for the production of Imprint of the image used 22. Photographic printing plate consisting of a photosensitive layer of less than about 2µ thick of a photosensitive Material that, when exposed, produces a physically developable image on a grained metallic carrier, characterized in that the grain size of the metallic Wearer, determined with the OSRM device, a curve from a summit height A between about 0.25 and 0.90, a peak position 3 between about 0.35 and 0.80 iuid with a psi value C gives between about 0.1 and 1.0. 23. Printing plate according to claim 22, characterized in that the Grain size of the carrier when examined with the OSRM device a curve with a peak height A between about 0.50 and 0.85 with a peak position B between about 0.60 and 0.75 and with a psi "C between about 0.65 and 0.90. 24. Printing plate according to claim 22 or 23, characterized in that that the metallic carrier is an aluminum carrier with a practically non-porous Aluminum oxide layer with a thickness of at least ta 14 Å on its surface is coated. 25. Printing plate according to hnpruc 22 to 24, characterized in that the light-sensitive layer additionally contains a water-permeable binder. 26. Printing plate according to claim 22 to 25, characterized in that the light-sensitive material is a silver halide. 27. Printing plate according to claim 26, characterized in that the Silver halide is silver chloride with an excess of chlorine ions. 28. Printing plate according to claim 22 to 25, characterized in that the photosensitive material is a reversibly activatable photoconductor. 29. Printing plate according to claim 28, characterized in that the Photoconductor contains titanium dioxide or zinc oxide. L e r s e i t e